(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Knowledge. v. 1-40; Nov. 1881-Dec. 1917"

;7|^f^ft^i^^S^ 



^iM, 













I gARSWELL Co, Limited S 
Bookbiud4>r». c 



TORONTO 



I PRINTKKS, I ■ 

I Law Hooks, A 



OF CAN/:: 

TORG NTO, 



Plainly Worded — Exactly Described, 




CONDUCTED BY MAJOR B. BADEN-POWELL AND E S. GREW MA 



'Let Knowledge grow from more to more " 

— Tenw.son'. 



Volume I. 

JANUARY TO DECEMBER, 1904. 



NEW SERIES 

Volume 1. 



a 

london: 

KNOWLEDGE OFFICE, 27, CHANCERY LANE, W.C. 

{All Rights Reserved.] 



SEP 27 1968 y 




London ; 
King, Sell & Olding, Ltd., 27, Chancery Lane, W.C. 



r, 



k 



K' 



\y 



/ 



KNOWLEDGE & SCIENTIFIC NEWS. 



111. 



INDEX. 



The letter K before a number rejers to tlujtinuaiij itumber oj " KNowmDGE." 

A. 



PAGE 



Achromatic Condenser ... 

.Aeroplane, A Motor ... ... ... ... 3 

,, Experinientti at the Crystal Palace iii, 154 

Agriculture, Recent Research in ... ... 43 

,, at the British Association ... 205 

.■\ir, Electric Discharges in ... ... ... 17 

" Airships, My," Book by Santos Uumont ... 133 

.■\itchison Field Glass ... ... ... 101 

Alligators ... ... ... ... ... ... 161 

.Altimctre, The ... ... ... ... ... 17 

Aluminium, Plating ... ... ... ... 176 

.Ambergris, A Precious Product ... ... 71 

Ancestry of the Elephant ... ... ... 11, 74 

„ ,, Camel 25 

,, ,, Carnivora ... ... ... 61 

.\ncient Calendars ... ... ... ... 1 

.Animals, Rare, Living in London ... 59, 170, 258 

„ Fasting 144 

,, Gluttonous ... ... ... ... 269 

\nimated Photographs of Plants ... ... 83 

.\ntelope, A Deer-like ... ... ... ... 124 

Anthropology at the British Association ... 204 

.Apes, Brain of Man and ... ... ... 97 

.Arctic Exploration ... ... ... ... 191 

" Argus," Attachable Mechanical Stage ... 47 

.Armadillos ... ... ... ... ... 188 

,, Arnold, R. B., Book by ... ... 275 

Asia, Central ... ... ... ... ... K.I. 

Asphalt -Mending ... ... ... ... 156 

Asses, Wild ... ... ... ... ...222, 293 

Association of Academies, The International... 132 

.Astrographic Catalogue ... ... ... 123 

.Astronomical Notes 

8, 41, 70, 95, 123, 158, 186, 220, 241 

,, Society, R., of Canada ... ... 242 

Astronomy in the Old Testament ... ... 234 

.Ataxia, Hereditary ... ... ... ... 103 

.Atlas, Photographic, of the Moon ... ... 40 

Axis of the Earth, A'ariation of ... ... 171 



Bacteria and Radio-activity 
Baden-Powell, Major, on Aeroplanes 
Badger, Duration of Pregnancy in the 

Balfour, Rt. Hon. A. J 

,, Henry ... 

Barometer 
Becqucrel Rays 
Beetles, Colour-Pattern in 
Benham, C. E. , on the Super .Solid 
Bickerton, Prof. .A. W., on Explosion 

Bird Life 

,, Migration ... 
Birds, Fossil 
Birkbeck College 

Blondlot " \ " Rays 

Blood of Men and Apes ... 



f Stars 



127 

'I. 154 

16 

197 

204 

77 
140 

4,S 
261 
244 

42 

41 

241 

18, 44 

246 



Borings on a Coral Island 
Botanical Notes 

9. 43.. 7-. 97. >-5. i^9. 221, 243, 267, 
Botany, at the British Association 
Bredechin, Prof. T., Death of ... 
British Association, The 

,, ,, Presidential Addresses 

Brook 's Comet 

Bryan, Prof. C. II., on .Stereo.scopic Pro- 
jection of the Light Cell ... 
Burnham's Measure of Double .Stars .. 
Burrowing Fishes 
Huxzard, Breeding of the 

,, Rough-legged 



c. 



Cachalot Whales 

Calcium, and Hydrogen Flocculi ... .■•41, 

,, as an Industrial Metal 

Calendars, .Ancient 
Camel, Ancestry of 
C;mals on Mars 

,, Nicaragua, an Eighteenth 

Map of 

Cancer, Latest Discoveries Concerning 

,, Problems 
Cape Jumping Hare 
Cathode Rays, Chemcal Effect of 
Ceylon Oyster Fisheries 
Chemical Conception of the Ether, Book by 
Prof. Mendeleeff 
,, effect of Cathode Rays 

Chemistry, Modern A'ievvs of ... ... 35, 

,, at the British Association 

Chess 
Chimpanzee, .An Intelligent 

,, and Gorillas 

Chlorophane 

Classification of Reptiles 
Gierke, Miss A., on Modern Cosmogonies 

K. 6, 30, 80, 178, 21 
Climates, Comparison of 
" Co;il Sack " in Cygnus 
Coccidai 

Cole, Greville .A., on the \"ital Earth 
Collier, J., on Variability in .Sociology 
Collins, !*., on Protective Resemblance of 
Insects ... ... ... ... 51, I 

Colour, Photography in .Natural 
,, of \'ariable Stars 

,, .Analvsis of. Book on ... 

,, of lobsters 

,, in birds ... 

,, of nestling birds 
,, in beetles 



I'A<iK 

292 

184 
190 

■97 
123 

92 
96 

42 

98 

126 



42 

151 

106 

I 

25 



37. 41. 67. 87, 96 
Century 

55 
14 

58 

170 

161 

6 



99 
161 



Comet, 



I i;o4 

Encke's 

1903 



S7. 79 

201 

K. 23 

294 
298 

72 
16 



256 

243 
302 
4, 250, 278 
285 
214 



208 

43 
186 

1G2 
70 
126 
271 
140 
123 
291 
220 



147. 243. 



IV. 



KNOWLEDGE & SCIENTIFIC NEWS. 



Comet's Tails, Some peculiarities of ... 

Conservation of Mars 

Constellations, and Ancient Calendars 
,, Antiquity of 

,, Snake forms in ... 

Coral Island, Borings on 

Cosmic Physics at the British Association 

Cosmogonies, Modern 30, So, 178, 211, 

Crocodiles 

Crystal, The Structure of 

The Birth of 

Cuckoo watching over its young 

Cunningham, J. T., Discoveries in Cancer 

Cygni, Nebulosities in ... 

D. 

Dalny 

Darwin, Francis ... 

Davison, C, on Recent Explosions 

Dead Sea, Saltness of ... 

Denning, VV. F., on November Leonids 

,, ,, Canals of Mars ... 

,, ,, Observations on Mars 

.. Jupiter 

Dipleidoscope, A New Form of 

" Discovery " Collections 

Dolls of the Tombs 

Double Stars, Measure of 

Dugongs, Similarity to Elephants 

Duration of Pregnancy in the Badger ... 

E. 

Earth, The Vital 

Earthquakes, Book on 
Eclipse Problems 

,, Mathematical Theory of, Book on 
Economic Science at the British Association 
Eggs, Great Auk's 

,, Decrease in Weight of ... 

,, Weight of 

Egyptian Fossils, New ... 

Eight-Cell, Stereoscopic Projection of the 

Electric Eye 

,, Discharges in Air 

,, Recording Apparatus, Patent 

,, Sparks, Photographs of 

,, Traction System 

,, Wave Measurement 

,, Ore Finding 

,, Equilibrium of the Sun 

,, Influence Experiment ... 
Electricity Works, Wind Driven 
Elephants, Ancestry of .. 

,, and Dugongs, Similarity ... 

Eliot, Sir John 

Emanation from Radium Bromide 
Encke's Comet, Return of 
Entropy, Book by Mr. J. Swinburne ., 
Equilibrium, Electric, of the Sun 
Ether, The Inevitable ... 
Evolution of Marsupials 

,, Principles of, Teaching the 

Explosions, Recent 
Explosives, Japanese 
Eye, Early Opening of the Right 



56, 



14; 



PAGE 

70 

281 

I 

118 

227 

3^ 
200 
K. 6 
161 
109 
182 
222 

14 
10 



17 
205 

94 
10 
21 
67 

41 
148 

95 

97 

185 

96 

15 
16 



285 
302 
187 
302 
202 
162 
222 
244 
124 
92 
16 
17 
24 
28 

49, 73 
131, 244 

157 
186 
269 

36 
4 

15 
200 
126 
291 



II, 



24.' 



133 
186 
178 
16 
302 

94 

158 

96 



20 


, 39 




194 




98 


35, 57 


, 79 




97 




lOI 




42 




125 




162 




125 




161 




161 


...131, 


244 




41 


••■ 3, 


III 




162 


... K 


• 13 




97 


■•■ 15, 


162 




124 




41 




246 




305 




45 


of 






175 




32 


...141, 


231 


... K. 3 




80 



F. 



Face of the Sky, Monthly 
" Facility " Object-Changer 
Falcon, Greenland, in Donegal 
Fenton, H. J. H., on Chemistry 
Fern, An Abnormal 
Field Glass, Aitchison 
Fishes, Burrowing 

,, Destruction of by Birds 

Flying 

Scales 
,, Classification of 

,, Habits of 

Fleming, Dr. J. A., Electric VVave Measui 

ment ... 
Flocculi, Calcium and Hydrogen 
Flying Machine ... 

,, Fish 
Fog Box ... 
Food, Primitive ... 
Fossil Reptiles 

,, New Egvptian ... 

Birds "' 

,, Mammals 

,, Coal, Microphotograph of 

Fourth Dimension, Conception of 
Fritschc, Dr. F. E., on Peat and its Mode 

Formation 
Funafuti, Coral Island Borings 
Fungi, Influence of 

,, as Links in the Chain of Life .. 
Fyfe, Mr. H. C, Death of 



G. 

Galactic Plane, Position of the 
Gazelle, A New ... 
Gelatine Plates as Light Filters 
Geodetical Instruments ... 
Geography, at the British Association 
Geology, Text-Book of ... 

,, at the British Association 

Geometry, Book on 
Gibbons in Sumatra 
Giraffe, A Sub-Species of 
Gore, J. E., on Giant and Miniature Suns 
Gorillas at the Zoo 

,, and Chimpanzis 
Gradenwitz, Dr. A., Continental Physical Notes 

,, ,, Telegraphically Transmitting 

Photographs 
Gramophone and Biograph 
Green, J. Reynolds, on Stimulus and Sensation 
,, on the Development of 
Parasitism 
Greenland I<"alcon in Donegal ... 
Greenwich, R. Observatory, Report on 
Guinea Fowl in Roman Dust Heap ... 
Gull, Yellow-Legged Herring ... 

,, and Fish 
Gun, a Ball-Bearing Rifled 

H. 

Hansard, Arnold G., Letter on Electric Traction 
Hare, Cape Jumping 



220 

43 
194 

49 
202 
163 
201 
163 
222 

42 

4 

246 

298 

17 

56 

196 

89 

114 
98 

1.59 
160 
187 

188 

247 



73 
170 



KNOWLEDGE & SCIENTIFIC NEWS. 



Harvard Collct^e Observatory.' ... 
Heat, Radium and 
Hedgehog, An American 
Hercules, Spiral Structure in ... 
Herdman, Prof., Report on Oyster Fisheries. 
Hereditary Ataxia 
Hereford, Bishop of 
Herschel Obelisk ... 

Hilton, Harold, on the Structure of Crystals 
Historical Charts, Blake's 
Horn Exhibition ... 
Horse, The Later History of the ... 171, 

,, The Ancestry of ... ... K 



I. 



246, 
. 16, 



241 

98 

'-5 

9 

6 

103 

206 

290 

109 

60 

162 

247 

293 



Ibis, Glossv, in the Orkneys ... 




126 


Indigo 




2, S3 


Insects, Protective Resemblance of ... 


• 51. 


n7 


,, African ... 




71 


Pest 




188 


,, Terrifying Masks 




208 


Instincts, Primeval 




42 


Instruments, Geodetical 




4P 


International Association of Academies 




•.^2 


Invar ... ... 




176 


Ivory, Supply of ... 


..1S9, 


2 -'3 



Janssen, M., Photographs of Sun ... ... 70 

Jones, Chapman, on Photography 

117, 146, 174, 219, 286 

,, ,, Book by ... ... ... 276 

Jordan, David Starr, " Animal Studies " ... 74 

Jovian Longitudes, Method of Determining ... 123 

Jupiter ... ... ... ... ... ... 148 

,, Fifth Satellite of ... ... ... 159 

,, Disturbances on ... ... ... 292 

,, and His Surface Currents ... ... K. 8 



" KaflRr, The Essential " ... ... ... 99 

Kepler and Astrology ... ... ... ... 181 



L. 



Lamb, Prof. Horace ... ... ... ... 199 

Lens, A Stereoscopic Single ... ... ... 127 

Leonids, Shower of ... ... ... ... 21 

Lobsters, Colours of ... ... ... ... 70 

Lockyer, Dr. W. J. S., on Sunspot Variation 181, 265 

Lowell, Observations on Venus ... ... 41 

,, Changes in the Martinn C.inals ... 96 

Lunar Apennines ... ... .. ... ... 64 

Lydekker, R., on Ancestry of the Horse ... K. 17 

>» ,, >, ,, Camel ... 25 

i> ,. ,, ,, Carnivora 61 

M ,, Fasting Animals ... . . 144 

>» ,, Later History of the Horse 171 

>f ,, Tibetan Animals ... ... 216 



M. 

Magnetism, Terrestrial ... 
,, Sunspots and 

Magnification in Microscopy 
Mammals, New ... 
,, Fossil 

,, of Central Asia 

Mammoth Skull in Kent 

Mantis 

Marriott, W., on Meteorology 

Mars, Canals on ... ... ... ••■37, 

,, Observations on ... 
,, New Chart of 
Marsupials, Evolution of 
Masscc, Geo., on the Influence of I'"uiigi 
Maunder, E. W., on Ancient Calendars 
,, ,, Can.-ils of M;irs 

,, ,, Is there .Snow on 

Moon ? 
,, ,, .Solar Atmosphere 

,, ,, .Snake Forms in C 

steliations 
.McClean, .\Ir. Frank, Death of 
Medusa of Lake Tanganyika ... 
.Mcndelceff, Prof., Book on Chcmic;il Cone 

tion of the Ether 
Metals, Action of Radium on ... 
Meteoric Observation 
Meteorology, Last Vear's Weather ... 

,, Practical 

Meteors, Leonids 
Microscopical .Society, Roval 

Table' ...' 

Microscopy 

K. 20, 21, 47, 75, 104, 134, 164, 2, 
Migration, Bird ... 
Milne, Prof., on tiie Displacement of tlie ]\ 

Mites 

Monkeys and Altitutle ... 
,, Brain of 

Mont Pelee, The Obelisk of 

Moon, Photographic Atlas of the 

,, Is there .Snow on 
Mosquitos in England ... 
Motor Aeroplane, A 
,, -Single-Phase 
Mouse, A New British ... 
Mummies, Natural 





9 


... 96, 


ji)i 




2 1 




42 
246 




268 




2.[f) 




13<J 


87, 96, 


26(1 




41 




242 




10 


...141, 


231 




I 




S7 


the 






64 




IS" 


on- 






227 




291 




7' 


ep- 






9) 




126 




242 


24. 50 


. 7^> 




167 


K. II 


, 21 


75. 105 


,'<>.^ 




225 


24, 250, 


306 




42 


)les 


171 


...104, 


'34 




<)6 




97 




3« 




40 




r,4 




124 




3 




93 




124 




2fK1 



N. 



N-rays, Phenomcn.-i 

National Physical Laboratory ... 

Natural History Specimens 

Nature Printing ... 

Nautilus and Flying Fish 

Nebula; 

,, Forms of 

.\nd the Milky Way 

,, In the Pleiades ... 
Nebulosities Round 7 Cygni 
New Genus, Botanical ... 
.Newton's Rings in Microscopical Objectives 
Nicaragua Canal, Old Map of ... 
Noble, Capt. William, Death of 
Nutcracker in Northamptonshire 



18, 44, 92 



102 

72 

23 
238 

l(>2 

41 
21 t 

2^16 

.•788 

10 

9 
25' 

1K4 
98 



VI. 



KNOWLEDGE & SCIENTIFIC NEWS. 



O. 



Obelisk on Mont Pelee 38 

Obser\atory, Greenwich, Report on ... ... 159 

,, Harvard College ... ... ••. 241 

,, Lowell 24' 

„ Paris ■ -;43 

• Old Riddle and the Newest Answer," bv 

John Gerard ... ... ... ... 98 

Ore Finding by Electricity ... ... .. 157 

Ormerod, Miss Eleanor, Autobiography . . 163 
Ornithological Notes 98, 126, 160, 187, 221, 267, 292 
Orthoptera, Preserving ... ... ... ... 47, 76 

Osprey Plumes, Real and Artificial ... ... 128 

,, In Surrey ... ... ... ■. 268 

Ovster, Pearl, Fisheries ... ... ... 6 



P. 



Paca-rana ... 

Palolo Worm, The 

Panorama Military Telescope .. 

Paradise, Birds of, in England 

Parasitism, The Development of 

Patents, Recent ... . . . • ■•■ 23, 

Pearl Oyster Fisheries ... 
,, Organs of Fishes ... 
Peat and its Mode of Formation 

Pelee, Mont 

Penguin, The Emperor ... .... 

Pericin, Dr. F. M., on Indigo 

Pheasants, Hybrid 

Photographic .Vtlas of the Moon 

Sun 

Photographs, Transmission by Telegraph 

,, ' Animated, of Plants 

,, Of Solar Granulations ... 

,, With the Yerkes Telescope 

Photography of Electric Sparks 

,, Registration of Star Transits by 

,, In Natural Colours 

,, Pure and .Applied 

117, 146, 174, 219, 235, 262, 
Photometry, Solar and Stellar ... 
Physical Chemistry Book 

,, Deterioration, Book on 
Physiology at the British Association 

,, Primer of ... 

Plants, Animated Photographs of 

Plover Kill Deer 

Pond Life Tanks ... 

Porter, A. W., on the Conservation of Mass... 

Preserving Specimens for Microscope ... 47 

Primeval Instincts 

Printing Telegraph 

Protective Resemblance of Insects 

Protyle : What is it ? 

Pvcraft, W. P., on Osprey Plumes 

(See Ornithological N 
Coloration of Nestlina; Birds 



Q- 

Qnaggas and Wild A.^jscs 

Quekett Microscopical Club (see under Micro- 
scopical Notes each month). 



268 
71 
177 
267 
114 

lOI 

6 
96 

175 
38 
98 

253 

160 

40 

70 

55 
83 

12 2 

124 

28 

95 

43 

286 
17 
99 

163 

204 

238 

83 
187 

7fi 
282 

■ 76 
42 
18 

51 
80 

128 

tcs.) 
271 



293 



R. 



Radiation, A Novel Phenomenon 




97 


,, In the Solar System 




266 


,, Variation in Solar ... 




186 


Radio-activity ... ... ... ... 77, 


07. 


248 


,, Bacteria and 




127 


,, Of Chemical Reactions 




282 


Radium ... ... ... ... 8, 77, 


■'J7. 


126 


,, Chlorophane and 




72 


,, .-^nd Heat 




98 


,, Emanation ... ... 




126 


,, Book on ... 




133 


,, Electroscope 




184 


Rainfall Last Year 




24 


Ramsay, Sir W., on New Gases and Radium 




8 


Ravens Nesting in Captivitv 




126 


Rays, " N," ' 




18 


,, Thought ... ... ... 




245 


Reade, T. Millard, " The Evolution of Earth 






Structure "... 




9 


Recording .Apparatus, Electric ... ... ... 




24 


Reptiles, Fossil . . . ... .:. 


15- 


162 


,, Classification of ... 




16 


Resemblance of Insects ... ... 


51. 


137 


Roberts, Dr. Isaac, Death of ... 




184 


Royal Society Medals ... 




295 


Rubber, A New Plant ;. 




9 



s. 



220, 266, 



St. Louis, Science at ... ... 

Salmon in Fresh Water ... 

Saltness of the Dead Sea 

Sampson, Prof. R. A., on the Mechanical State 
of the Sun ... 

Satellite 

,, Jupiter's Fifth 
,, Saturn's Ninth 

Saturn 

School on the Ocean 

-Scintilloscope 

Sclater, Dr. P. L., on the Thylacine ... 
,, ,, Cape Hare 

,, ,, Grevy's Zebra 

Scott, Mrs. D. H., on Photographs of Plants 

Sea, Saltness of the Dead 

Sea Sickness, Apparatus for Preventing 

.Secchi's Fourth Type of Stars . 
,, Third Type ,, 

Secondary Battery, Patent 

Sedgwick, .\dam ... 

-Selenium, Conductivity of 

Sensitive Plant, Photo of 

Shackleton, W., " The Face of the Sky " each month. 

Shark, An English 

Shenstone, W. .'\., on Radio-activity ... •■•77' 

Shimose 

Single-Phase Motor 

Smell, N-rays and 

Smithsonian Expedition to Observe the 1900 
Eclipse 

Snake Formation in Constellations •••227-, 

,, Salamander ... ... ... 

,, Stories ... ...... ... ... 72 

,, Cannibalism in 222 

.Snow on the Moon? Is there ... ...■ ... 64 



296 

223 

10 

119 

287 

159 

20, 266, 287 

91 

264 

236 

59 
170 

258 

83 

10 

160 

70 

158 
24 

55 



85 



158 

93 
92 

159 
301 

293 



KNOWLEDGE & SCIENTIFIC NEWS. 



Vll. 



Sociology, Variability in 
Solar-activity and Magnetism 

,, Atmosphere 

,, Eclipse of 1900 

,, Granulations 

,, Parallax 

,, Photometry 

,, Radiation, Variation of . 

,, Research Expedition 
Somerville, Dr. W. 
Sound of l*!xplosions 
Sparks, Electric ... 
Spectrometer Table, New 
Spectrum of Stars 
,, .Analysis 

Spencer, Herbert, 

,, Autobiography of 
Spider, Leg and Foot of 
Spinthariscope, The 
Spiral Structure in Hercules 
Star, Transits, Registration of 

,, Double, Measure of 

,, Catalogue ... 

,, Spectroscopic Binary in Pegasus 

,, an Interesting" Variable . 

,, Colour of \'ariable 

,, of Secchi's Third Type . 

,, ,, Fourth Type 

,, Binary 
Stars, Radial Velocities of 

,, Secchi's Fourth Type . 

,, I'^xplanation of 
Stellar Magnitude of the Sun . 

,, Photometry 
Stereoscopic, Projection of the Kisjht-Cell 
,, Single Lens 

,, Projection 

Stimulus and Sensation ... 
Stork Breeding at Kew 
Strahan, Aubrey ... 

-Strutt, Hon. R. J., Radium Electroscope 
Sun, Stellar Magnitude of the 

,, Mechanical State of the 

,, Photographic Atlas of 

,, Electric Equilibrium of the 
Sunspots ... 

,, and Terrestrial Magnetism .. 

,, Variation in Latitude 15c), 181, 237, 

Super-solid, The ... 
Sverdrup, Otto, Book on the Arctic ... 

T. 

Telegraph, Printing 

,, Transmitting Photographs 

,, Wireless 

Telephone, Wireless 
Telescopes, Large v. Small 

,, "Panorama" Military 



I'AGi-; 
214 
291 
150 

159 
122 

■5^ 
1" 
186 
187 
206 

94 
16 

159 

284 

■ 1.'? 

116 

148 

68 

9 

95 

96 
123 
12^ 
I.S8 
186 

158 



1 8 



70, 



12-? 

26'l 

9 
17 

q2 
127 
2g6 

89 
160 
201 
184 

9 

119 

70 

186 

I.ST 
96, III) 
265, 290 

4.=; 

iqi 



18 
56 

72 
160 

K. 12 40 



Teletyping 

Temperature, Mean 
Thylacine, The 

Tibetan Animals ... 

Touracon, A Nestling 

Traction System, Electric 

Transmission of Photographs by 'lelcgraph 

Turbines, Patent ... 

Turkeys, Brush, Breeding in Conlinenicnt 



V. 



i'.\r.K 
IS 

24 

.S9 

216 

292 

49. 73 

23 
24.3 



Variability in Sot-iology ... 


214 


W-locities, Kadi:il, of Stars 


70 


of I he Piei.ides 


TS7 


X'enus, Observ.-itions on 


41 


\"ipcrs' Poison 


1 89 


X'olcauic Obelisk ... 


38 



. iCk), 



w. 

Wave Measurement, Ivlectric ... 
Weather, Last Year's 

,, Plant, Photo 

Weeds, dried, as Drugs 
Whales, Cachalot 
,, Collisions 

,, Destruction of 

Wind-driven filectricity Works 
Wireless Telegraphy Experiments 

,, Telephony 
Wolf, Dr. Max, Xelnilosities in Cygnus 
Woodward, A. S., on the Ancestry of 

Elephants ... ... ... II 

Worm, The P;ilolo ... ... ... ... 71 

Wright's Motor .Aeroplane ... ... ... 3 



Y. 



^'cndell, Mr., Observations of the Colour of 

Stars 186 

\'erkes Observatory ... ... ... ... 124 

Voung, Prof. Svdnev ... ... ... ... 201 



131 

24, 50, 76 
84 

1 66 
42 
96 

125 
36 
72 

246 
10 



•77 



z. 



Zebra Training ... ... ... ... ... 97 

,, (irevy's ... ... ... ... ... 258 

Zittel, Karl von, Death of ... ... ... 16 

Zodiac, Change from Taurus to Aries .... 123 

Zoo, Rare Bird at the .. .. ... ... 124 

Zoological Notes 

15, 41, 70, 96, 124, 161, 189, 222, 246, 268 

Zoology at the British .As.sociation ... ... 202 



Vlll. 



KNOWLEDGE & SCIENTIFIC NEWS. 



ILLUSTRATIONS. 





PAGE 


Aeroplane.. 


III, ii3> 154-5 


Animated Photographs of Plants 


83-86 


Arctic Exploration 


192 


Rricteria and Radio-activity 


127 


Ralfour, Rt. Hon. A. J., Portrait 


197 


„ Henry, Portrait of 


204 


nirds, Nestling ... 


273 


Biitternies " 


... 52, 137, 210 


Camel, Ancestry of the ... 


26 


Cancer, Discovery 


15. .^9 


Capo Jumping Hare 


170 


Carnivora?, Ancestry of the 


61 


Chimpanzis and Gorillas 


300 


Constellations, Snake Forms in 


227-9 


Coral Island, Borings on 


33' 34 


Crystals, The Birth of 


183 


Darwin, Mr. Francis, Portrait ... 


205 


Dolls of the Tombs 


185 


Electrical Ore Finding ... 


157 


Elephants' Ancestry 


11-14 


Eliot, Sir John, Portrait 


200 


Flowers, " Physiotype " 


239 


Fossil Coal ... 


305 


Fungi 


...141, 231, K. 3 



Hi^reford, Bishop of, Portrait 
Her.schel Obelisk 
Horse, Bones of ... 

Indigo Plants 

Insects with Terrifying Masks 

Jupiter 

Kummeter 

Lamb, Prof. Horace 
Lunar Apennines 



(Titles in heavy type are those of whole page Plates.) 



Mars 

Meteorological Charts .. 

Mont Pelee, Obelisk 

Nebula; of the Pleiades 
Nebulosities in y Cygni 

Osprev Plumes 
Ovster Fisheries ... 



" Panorama " Military Telesccpe 
Parsons, Hon. Charles, Portrait of 
Peat and its Formation ... 
Photographs of Electric Sparks 
Printing Telegraph 



Radium and Radio-activity 
Resemblance of Insects 



PAGE 

... 67, 87 

168-9 

... opp. 38 

289 
opp. p. 10 



129 

7 

177-8 
203 

'75 
29 

19 

77. 107, 283 
51-55- 137-9 



206 

290 

... K. 17 

253 
208 

opp. K. 8 

245 

199 

opp. 64, 65 



Sherrington, Prof. C. S., Portrait 
Single Phase Motor 
Smart, Prof. William, Portrait 
Somerville, Dr. William, Portrait 
Spider's Leg, magnified... 
Stereoscopic, -Single Lens 

Pictures 
.Strahan, Aubrey, Portrait 
Sun Spots. 
Sunspot, Great, of 1903 

Telegraphic Transmission of Photographs 
Thylacine, The 
Tibetan Animals ... 



Wind-driven Electricity Works 
Wright Aeroplane 

Young, Prof. Sydney, Portrait .. 

Zebra, Grevy's 



205 

93 
203 
206 
opp. 148 
127 
296 
201 
121 
151-2 



56 

60 

216 



37 
4 



259 






Jaxvary. 1904.] 



KNOWLEDGE. 




Founded by RICHARD A. PROCTOR. 



Vol. XXVII.] LOXDOX: JAXUAEY, 190J.. [No. 219. 



CONTENTS. 



P*OK 
1 



Central Asia and Tibet 

Fungi as Links in the Chain of Life. — I. The Nature, 
Habitats and Distribution of Fungi. My G. M.^ssbe. 
{IllKslrated) 3 

Modern Cosmogonies. VI.— World Building out of 

Meteorites. By Agnks M. Clkrkk ... . ... 6 

Jupiter and His Surface Currents. By the Rey. T. E. R. 

Phii.i.ips, m..\., f.b.a s. (Illustrated) (Plate) ... ... 8 

The Shower of Leonid Meteors in 1903. By W. F. 

Dbvninq, r.B.A.8. ... .. ... ... . .. 11 

tetters : 

L.KBGE verfus Small Telescopes ix Planetary Work. 
By A. Stanley Williams 12 

The Obchid Cephalantheba Geandifloba. By C. E. 
Clabk. (lUmtrated) 12 

A Foo Bow. By Maey Fraseh 13 

Obituary;— Hebbebt Spencer 13 

British Ornithological Notes. Conducted by Haeet F. 

WiTHBRBY, E.Z.8., M.B.o.r. ... ... ... ... ... 13 

Notes 13, 22 

Notices of Books 14 

Books Receited ... ... ... ... ... ... 16 

The Ancestry of the Horse. By R. LYDEkKEs. (Illux- 

trated) 10 

Microscopy. Conducted by F. Shillfn-oton Scales, f.b.m s. 20 

The Face of the Sky for January. By W. Shacklbton, 

P.R.A.s. {Illustrated) ... •■ .. ... .. ... 22 

Chess Column. By C. D. Locock:, b.a 23 



CENTRAL ASIA AND TIBET.* 

Dr. Sven Hedin is without doubt the most remarkable 
explorer now living. From an early age he adopted 
exploration as a profession, and Asia as a speciality. His 
training to this end has made him able to perform single- 
handed most extensive journeys into unknown parts of 
Central Asia, which have yielded splendid scientific results. 
His organising powers are great. As a topographer lie has 
no rival, while he is also able to undertake successfully the 
work of a meteorologist, geologist, biologist, ethnologist, 
archseologist, and many other specialities, and thus is 



• " Central Asia and Tibet. Towards the Holy City of Lassa." 
By Sven Hedin. (Hurst & Blackett.) 2 toU. Illustrated. £2 2b. net. 



empowered to give an accunite picture of the cdiuitry 
through which he travels. 

The scientific results of his latest expedition hiive still 
to lx> worked out, and their ])ul>lication in detailed form 
is, we are glad to say. assiu'ed. In the present volumes 
we havt! only the narrative of his travels, with an inkling 
of what is to come in the way of valuable scientific 
results. 

It is possible in the limits of this notice to give only a 
general idea of Dr. Hedin's journeyings. From the middle 
of 18;»;' to the middle of V.Wl he was travelling almost 
incessantlv, his various routes in Asia extending to a total 
of some "(;000 miles. TIm^ narrative of these journeys, 
contained in these two fine volumes of over (JOO pages each, 
is in the form of an orderly journal, solid with fact and 
detail, b\it at the same time vividly written, so that one's 
interest in the chronicles of each day's doings is held to 
the end. The narrative, in fact, not only gives a lifelike 
picture of the country through which the explorer i)assed, 
and of how he got through it, l)ut reveals besides many a 
deep insight into Asiatic character, while of his own 
character the author unconsciously draws a most in- 
teresting picture— great determination and dogged phutk, 
with now and again a susjiicion of rashness, untiring 
energy, a keen foresight, cheerfulness under all circum- 
stances, a singular humane and sympathetic nature, are 
among the characteristics displayed. 

In August, 1899, Dr. Hedin reached Kashgar, in Turke- 
stan. Equipping there a carefully-organized caravan, he 
proceeded to the Yarkand Daria, or Tarim, the great river 
which flows through the deserts of Eastern Turkestan. 
Here at Lailik began the first and perhaps most important 
part of his journeys. Converting with immense labour 
and great ingenuity a ferry boat into a floating residence 
and observatory, he committed himself to the broad waters 
of the lonely Tarim. The greater part of the first volume 
of the narrative is occujiied by an account of this almost 
idyllic journey. But it was a journey of great geographical 
importance for the hitherto little kno-ivn and badly-mapped 
Tarim is now, by the labours of Dr. Hedin, the best- 
mapped river out of Europe. 

For months, day after day, as the boat floated down the 
great river, the author sat glued to his table, mapping on 
a large scale every twist and turn of the stream, checking 
and recheckiiig his measurements, frequently measuring 
the depth and width of the river, and the velocity and 
volume of its waters. As long as the boat was moving 
there was no time for relaxation. " I was never able to 
quit my post for an instant to stretch my legs. VVe 
hardly ever travelled more than ten minutes in a straight 

line Hence I had to keep my eyes upon the 

compass." But if the work was hard, and perhaps many 
would think monotonous, Dr. Hedin was enchanted by 
this voyage. The scenery in parts was beautiful. " The 
forest stretched right d(jwn to the very brink of the river. 
High up on the sky-line ran the green coping 
of the poplars' crowns, making a dense curtain of foliage 
which seldom allowed a glimpse of the tree-trunks to 
o-leam between-green, l)ut green shot with various shades 
Sf rich brown, so rich that they would have been harsh 
luid their effe(;t not been softened by the hazy sky behind 
them." But at other times the country through whicli 
the river ran was utterly barren, the soil being sand. 
And as the Great Takla Makaii Desert was reached " we 
were engulfed in that awful Asiatic silence — a silence as 
of the dead. No greeting came to meet us from the heart 
of the desert. The river— the river alone— sang its 

rippling song to the irrespimsive sand Very 

strange to be crossing one of the earth's greatest deserts 



KNOWLEDGE. 



[January, 1904. 



by water ! Not so very long ago I had nearly died there 
for want of it." 

And not only did the scenery change as they drifted on, 
but the fiery heats of summer were succeeded by the 
violent autumn storms, and then the winter crept steadily 
and remorselessly on. The surface of the river one morning 
was spangled with patches of ice. Then a fringe of ice 
crept out day after day further from the banks, and the 
air was full of murmurs from the grmiliug ice, but there 
was still time to go many miles before the passage was 
blocked completely by the ice. Then winter quarters were 
formed, and the caravan, which had made the long journey 
by land, was successfully joined. " Never," writes Dr. 
Hedin, "was a journey of that magnitude carried through 
so comfortably and so successfully." And we believe him, 
for with little danger and with no great difficulty for so 
resourceful and intrepid an explorer, a thousand miles of a 
practically unknown river was most minutely investigated 
in the space of some three mouths. 

Dr. Hedin is not one to rest on his oars. No sooner 
had he got his winter quarters comfortably arranged than 
he started out on a perilous journey southwards across the 
Takla Makau Desert to Cherchen, situated on the river of 
that name. This desert journey in the middle of a very 
hard winter, with temperatures of many degrees below 
zero, and frequent blinding suow-strirms, was a very trying 
piece of work, but it was accomplished with the loss of 
only one camel. 

After an excursion to the south-west from Cherchen, 
which involved a very cold ride of 20U miles. Dr. Hedui 
brought his caravan back to his winter ijuarters, travelling 
for the most part by the ancient bed of the Cherchen 
River. Meanwhile his head-quarters camp had become 
"an important market, well known throughout all the Lop 
country, and immediately outside its precincts there grew 
up a ring of small ' suburbs,' where tailors, smiths, and 
other handicraftsmen came and plied their several 
trades." And Dr. Hedin became quite a king in the 
Lo]) country, and was able to set right many injustices to 
the poor. 

In the springs of 1900 and 1901, Dr. Hedin turned his 
attention to the district of the famous Lt)p-nor and its 
sister lakes. His work here was very important and 
interesting. The Tarim empties itself into the great 
depression of the Lop Desert. It has been long suspected 
that the lake into which this great river discharges its 
waters has shifted from time to time. Dr. Hedin has 
amply proved this to be the fact, by an examination of the 
Kara-Koshun Lakes, into which the river now empties 
itself, and by a careful survey and levelling of that part 
of the desert in which the old lake was suspected to have 
existed. Moreover, he found that the present lake was 
actually travelling back to its old bed. " Nor is it sur- 
prising," he writes, " that such should be the case in this 
desert, which my survey pi-oved to be almost pert'ectly 
horizontal. While the Lake of Kara-Koshun, which had 
existed a long time in its southern half, was being filled 
up with mud, drift-sand, and decaying vegetation, the arid 
northern half was being excavated and blown away by the 
winds, and thus being hollowed out to a deeper level. 
Now these changes of niveau are determined by purely 
mechanical laws and local atmospheric conditions ; con- 
sequently the lake which serves as the terminal reservoir 
of the Tarim system, must be extremely sensitive to their 
influence. . . . Then vegetation and animal life, as 
well as the fishing population, inevitably accompany the 
water as it migrates, and the old lake-bed dries up." In 
connection with this last observation, Dr. Hedin made a 
most important historical discovery. In the spring of 
1900 one of his men found by a lucky chance, in the middle 



of the desert, some old ruins. The next spring these were 
searched for and rediscovered. The material obtauied 
from them has not yet been fully worked out, but enough 
has been done to show that this spot, on the shores of the 
ancient Lop-nor, was the site of Lou-Ian, an important 
country in olden times, since it was situated between the 
great northern highway and the great southern highway 
from China to Europe. Long known historically to the 
Chinese, its position hitherto has never been accurately 
fixed. "How difterent, how exceedingly different this 
region was now compared with wliat it must have been 
formerly! Here was now not a single fallen leaf; not a 
single desert spider. . . There was only one power 

which brought sound and movement into these dreary, 
lifeless wastes, namely, the wind. ... I can imagine how 
beautiful a spot it was — the temple .... embowerered 
amid the shady poplar groves, with an arm of the lake 
touching it. . . . Round about it were the scattered 
villages. -. . . Southwards stretched far and wide the 
bluish-green waters of Lop-nor, set about with forest 
groves. . . . Look upon that picture and then look 
upon the picture of the scene as it is now ! Au endless 
array of cenotaphs ! And why is this ? It is simjily 
because a river, the Tarim, has changed its course." For 
an account of the many difficulties, hardships, and dangers 
that the explorer and his party experienced in the explora- 
tion oE this great desert and the surrounding country, we 
must refer our readers to the traveller's own modest but 
giaphi<- account. 

Dr. Hedin's ne,Kt and last great journey was an 
exceedingly long and trying one across the northern part 
of Tibet. For this journey he organised an immense 
caravan of camels, horses, and asses, but so difficult was 
the country, and so great were the hardships, chiefly on 
account of most of the time being spent at great altitudes, 
that very few of these animals survived, while several men 
died from the same cause. Dr. Hedin is not one to make 
much of hardships and difficulties, and his statement with 
regard to this journey is therefore significant. " For my 
part," he writes, " I would rather cross the Desert of Gobi 
a dozen times than travel through Tibet once again in 
winter. It is impossible to form any conception of what 
it is like ; it is a vei'itable via dolorosa .' " And we 
might add that there would have been little ciiauce of any 
less hardy or experienced traveller getting through at all. 
During this journey Dr. Hedin made a ]ilucky dash 
towards Lassa in the disguise of a Mongol pilgrim. But 
the Dalai Lama had got wind of his big caravan 
far away in the mountains, and he was stopped veiy 
firmly, but certainly not unkindly, on the threshold 
almost of his goal, and eventually escorted back to his 
caravan. After this the Tibetans continually escorted 
the caravan, keeping a small army on its flank, and 
effectually preventmg the explorer from going to the south. 
In view of our present advance into Southern Tibet, 
it is of interest to note that Dr. Hedm considers that the 
Tibetan's " policy of isolation during the last half century 
or so has not been dictated by religious, but by political 
motives. Their tactics, peaceful, but so far successful, 
have aimed at guarding their frontiers against Europeans." 
None but Europeans are tabooed. " Still Tibet will have 
to meet her destiny," says the author, and the day now 
seems near at hand 

As to the narrative in general, we may say that it is a 
most engrossing account of a very remarkable series of 
explorations. The book is well produced in every way. 
It has most excellent maps, and the illustrations from the 
author's photographs (over which he took the greatest 
possible pains) and sketches are exceptionally good. — ■ 
H, F. W. 



1904.] 



KNOWLEDGE 



FUNGI AS LINKS IN THE CHAIN OF LIFE. 

I.— THE NATURE. HABITATS, AND DISTRIBU- 
TION OF FUNGI. 

By G. Jl.vssEE. 

Fuxr.t iiulnde the mushrooms ami to.ulstools, as well as 
moulds, mildews, trutHos, puff-balls and yeasts, and 
number altogether between fifty and sixty thousand 
different kinds. 

It is only by eomparins: thoir modi' of life with that of 
other groups of plants that tiie true nature of fungi and 
their special chanicteristios can be clearly understood. 
Flowering plants, ferns, mosses, seaweeds and lichens, in 
fact all plants with the exception of fungi, possess 
chlorv>phyll ; owing to the action of which they are enabled 
to use c-arbonic acid and other inorganic substances as 
food. Now the absence of chlorophyll must be considered 
as the most distinctive hall-mark of the fungi, and its 
absence implies their inability to utilize inorganic sub- 
stances as food. This feature places fungi on a par with 
animals, inasmuch as both agree in requiring organic food. 
This fact is obvious in the cuse of those fungi that develoji 
as parasites on living plants, as the destructive rusts and 
mildews on wheat, barley, and numerous other plants, both 
wild and cultivated. Neither would anyone doubt the 
statement in the case of fungi growing on, and consequi-ntly 
obtaining their food from rotten wood or dead leaves. 
The case is not at first sight so evident, where fungi, as 
the common mushroom, spring directly from the ground ; 
when it might be supposed that the fungus obtained 
its food from the same source as the grass growing 
around it. 

Careful examination, however, would reveal the fact that 
the spawn of the mushroom derived its food from the 
decaying portions of grass an<l humus present, and not 
from the soil. It will be remembered that when mush- 
rooms are cultivated artitieially, the spawn is placed in 
manure, which is organic matter, although dead and more 
or less decomposed, and is not to be compared to such 
inorganic substances as carbonic acid, obtained from the 
air, and certain salts derived from the soil, which furnish 
the grass with its food. 

Now this condition of things naturally prevents the 
fungi from being pioneers in the dispersal of plant-life 
over the globe. Mosses, algae, and other simple forms of 
chlorophyll-ljearing plants, requiring only moisture, air, 
and soluble rock constituents as food, can manage to grow 
in barren and hitherto lifeless regions, if their seeds happen 
to l>e carried by wind or other agents. This is not so with 
fungi, which, for the reasons already stated, require organic 
focxl. 

There are no other fast lines between fungi and other 
members of the Vegetable Kingdom, all other distinctions 
being only differences of degree. Taking structure, we 
find that the characteristic unit, a cell with a well-defined 
wall or enclosing membrane, forms the groundwork of 
fungi, exactly as m all other plants, only in fungi the com- 
ponent cells are not differentiated into what are known as 
vessels, cork-cells, bast, &c., as in the higher plants. The 
reason for this absence of specialized structure in the 
fungi is the comparative absence of division of labour in 
these plants as compared with ferns and flowering 
plants. 

To understand this point of difference it must be remem- 
bered that in all except the very simplest of plants, which 
often consist of a single microscopic cell, there is a well- 
marked division into a vegetative and a reproductive stage; 



and even in the simple one-celled plants alluded to above, 
the one cell constituting the individual spends the first 
period of its existence as a vegetative, and tin' last part as 
a reproductive body. 

By the vegetative portion is meant all structures and 
work done for the welfare of the iudividual ; whereas the 
reproductive phase is entirely for the pur|)o.S(' of pro- 
ducing other individuals of the same kind, usually from 
seeds. 

Now if we take an oak tree as an example of one of llie 
chlorophyll-bearing jilants, the root, trunk, branches aud 
leaves, in fact every part except the flowers an<l fruit, 
belong to the vegetative stage, in other words all the parts 
mentioned are necessary for the coutinuaucr of life m the 




'., * m '^ 







Fig. 1. — .A. typical Agaric or gill-bearing fungus (.■<</arici(.t//vs/ri>). 
The part above the ground-line is the reproductive portion ; tile part 
below is the vegetative portion. Natural size. The ligureon the right 
shows two basidia bearing four spores each. Magnified .500 times. 



individual tree under consideration. As the oak lives for 
many years, the division of labour, or different kimls of 
work necessary to enable it to do so, are many aud varied. 
Of primary impt)rtance is a special arrangement for 
obtaining food from the air and the soil, converting the 
same finally into parts of the tree, and enabling the food 
to spread to every growing portion of the plant. Then, 
again, certain portions of the structtu-e are told oft' for the 
purpose of giving strength to the whole fabric, so that t he 
tree can withstand the force of the elements. 

As there is a limit to the life of the oak tree, in common 
with every other living organism, some provision is 
necessary for the continuance of the same kind of tree in 
the future. This necessity is provided for by the production 
of flowers ; these in the case of the oak eventually give 
origin to acorns, or seed, which in due course develop into 
other oak trees. This represents the reproductive cycle of 
the oak tree, and it will be remarked that, so far as volume 



KNOWLEDGE. 



[January, 1904. 



is eoncerued, it is very small compared to the permanent 
vegetative jx>rtion of the tree. 

Now, as a rule, in fungi the above proportions of the 
vegetative and reproductive portions of the plant are 
reversed as compared with the oak tree ; in other words, 
the reproductive portion of a fungus is much larger, and 
also more conspicuous than the vegetative portion. 



fihlM^. 




Fia. 2. — A second type of Basidiomyeetes {Clavaria aliefina). 
The entire branched portion ia covered with basidia bearing spores. 
Common in our pine woods. Natural size. 



If we take as an illustration the common mushroom, the 
aspect of which is familiar to most people, tlieu what is 
presumably considered to represent the whole plant — 
namely, the stem, cap, and gills— only in reality represents 
the reproductive portion of the fungus, being, in fact, the 
exact equivalent in function of the flowers in the oak ; 
the equivalents of seeds, called spores in the fungi, being 
produced on the surface of the gills. On the other hand, 
the vegetative portion of the mushroom consists of the 
comparatively small portion of white thread-Uke spawn or 
mycelium ramifying in the manure or other substance on 
which the fungus is growing. 

The same arrangement of parts is practically true for 
all other fungi ; the portion visible to the naked"eye, how- 
ever varied its form or colour, represents only the repro- 
ductive portion ; whereas the vegetative part is buried in 
the substance from which the fungus obtains its food. 

The popular belief that the mushroom and other fungi 
grow in a single night is not correct; it is quite true that 
when the mushroom has reached a certain stage of develop- 
ment, one or two days suffices for it to attain its full size 
afttr it appears above ground. Before this final spurt 
is reached, however, the baby mushroom has been growing 
for some weeks, and undergone various changes of struc° 
ture and development before it emerges above-ground. A 
little thought will recall to mind the fact that mushrooms 



do not spring up \vithin two or three days after the forma- 
tion of a mushroom bed, but several weeks elapse before 
the mushrooms are ready for the table. 

As to the origin of the fungi, the opinion held at the 
present day is that they originated or evolved from the 
algae or seaweeds, or their freshwater representatives. 

The most primitive groups of fungi are aquatic in 
haltitat, and closely resemble in structure certain algse ; 
in fact, at the beginning of the fungal group a fungus was 
an alga devoid of chlorophyll, the parasitic habit adopted 
by the pioneers of the fungi enabling them to dispense 
with this green substance. The sequence of evolution 
from these primitive types of fungi to the most modern 
members of the group — the agarics or gill-bearing fungi, 
and the puffballs — is fairly complete, and in evidence at the 
present day. 




Fio. 3. — A third type of the Basidiomyeetes (Dictyophora 
phalloidea). The entire upper portion is enclosed in the hollow 
covering or volva, until the spores are mature, when the stem 
elongates and bursts through the volva, and the crinoline-like network 
expands to form a landing-stage for insects, who devour the slime 
containing the spores, which is produced on the dark upper portion 
of the stem. Natural size. Not uncommon in Brazilian and other 
tropical forests. 



On the other hand, had the agarics and puffballs only 
been met with at present, the true origin of the group 
would never have btea suspected, so completely have all 
ti-aces of primordial structure and afinuity been effaced, 



Jantary, 1904. 



KNOWLEDGE 



combined with a complete loss of all trace of sexual 
reproiliK'tion. 

The iiiiinv causes combined to effect this remarkable 
chauge cannot be discussed here ; suffice it to say that the 
transition from an aijuatic to a terrestrial habitat is a 
main factor. 

The fuuiri are primarily divided into two groups, 
dej^iending on the mode of oriirin of the spores or 
reproductive bodies. lu the first or older group, dating 
from their secession from the alg;e. the spores are produced 
Inside sjiecial cells called axci, and the s[>ores are leclinically 
described as axcosjiores. In the older representatives of 
this group, that is those nearest to the alga-, there is a 
distinct motle of sexual rej>rodiictiou, in many instances 
indistinguishable from that presented by many alga;, but 
as the members invaded dry land tlie .sexual mode of 
reproiluction gradually disap|>eared, and is now com- 
paratively rare ; nevertheless the same general form of 
spore-producing structure is maintained. 

Now as these f uugi became more ;iiid more accustomed 
to existence on dry land, a most important addition to 
their meaus of reproduction gradually evolved. This 
consisted in the development of secondary kinds of 
rejiroductive bodies, technically called conidia. Now conidia 
more or less resemble ordinary spores in structure and 
appearance, but differ in not being a sexual product. 

This group of fungi, collectively known as the Ascomy- 
cetes, inchides many thousands of different kinds, large 
muiibers of which are very minute, and known only to 
those specially interested in the study of the fungi. 

Among kinds belonging to this group, and fairly well 
known, may l>e enumerated the Morels. Truffles, Yeasts, 
and certain of the minute fonus popularly known as 
moulds and mildews. 

The second large group, called the Basidiomycetes, have 
the spores borne on the surface of special cells called 
hamdia, hence the spores are spoken of as basidiospores. 
In this group there is no vestige left of the sexual mode 
of reproduction. The representatives of this section are 
usually much larger in size than those of the Ascomycetes, 
and include such well-known forms as the common mush- 
room, toadstools, puffballs, and the woody, bracket-shaped 
or hoof-shaped fungi growing on trees. It has already 
lieen stated that secondary forms of fruit are produced by 
fungi, but it is necessary to enter more into detail 
respecting this matter, as the extremes to which this idea 
is carried out in certain groups has no parallel elsewhere 
in the vegetable kingdom. 

In some fungi the different stages which together form 
the complete cycle of development are as different iu 
general appearance and relative size as that between a 
lK>ppv and an ash tree. Not only is this the case but the 
various forms usually grow at different periods of the 
year, one may be an annual and the other a perennial 
condition ; and, finally, when parasites, the forms may 
grow on different kinds of host-plants. 

As an instance of such multiplicity of forms repre- 
senting phases in the life-cycle of an individual, may be 
mentioned the common and very destructive wheat rust. 
The spring stage of this fungus appears under the form of 
clusters of miniature cups with frmged edges, filled with 
orange spores, on living leaves of the barberrv'. The spores 
of this form are scattered by wind, and those that happen 
to alight on a blade of wheat soon germinate and enter 
the tissues, and in course of time produce minute streaks 
of a rust colour on the surface of the living leaf. The 
spores of this second condition, dispersed by wind, inocu- 
late other wheat plants, and as the spores are produced in 
rapid succession throughout the summer, it can be readily 
understood how quickly an epidemic of disease can spread 



after a parasitic fungus has once secured an entrance. 
Towards the autumn, a third form of fruit is produced on 
the fading wheat leaves, (piite dilTereut in appearance from 
either of the two stages previously tnentioned. The spores 
of this third stage are called renting apores, Ijecause they 
remain unchanged until the following spring, when they 
germinate and iuDculate young barberry leaves, which 
results iu the pro<Iucti(in of the first stage of the fvmgus 
again, and the cycle of develo[imeut proceeds as before. 

Some fungi have two distinct forms iu the life-cycle ; 
some three, as wheat rust ; some four or even more. In 
some instances, one form of the cycle can be omitted at 
times, as in the case of wheat rust, where the stage on 
barberry is dropped altogether in some countries. 

Thousands of different fungi have tlie individual made 
up as it were of a number of distinct, different looking 




Fig. 4. — An example of the Ascomjcetes fPeziza acetahulumj. 
The asei line tlie inside of the cup. Natural size. On the left is an 
ascus containing eight spores. Magnified 500 tiimes. Not uncommon 
on the ground in our woods. 

parts growing at different periods of the year under 
different conditions, and fulfilling varied functions in the 
life of the complete plant. Tlie use of the quickly-growing 
summer condition is to furnish an enormous number of 
spores, by which the fungus is enabled to extend its 
geographical distribution ; whereas the autumn form, pro- 
ducing resting spores, is for the purpose of preserving 
the species in time, by bridging over the period when the 
plant on which the fungus is parasitic is not growing. 

The various methods of spore dispersion as occurring 
in the fungi are interesting ; only a few of the most 
pronounced can be noticed here. By far the most 
imiversal agent in effecting the distribution of spores is 
wind, as may be observed when a ripe puffball is crushed 
under foot. Insects are also answerable for the extension 
of many fungus epidemics, Ijy alternately feeding on, or 
visiting diseased and healthy plants, and in so doing 
unconsciously conveying spores from one plant to another. 
Perhaps the most interesting instance occurs in a group of 
fungi to which our " stinkhom " l)elong8. Most of the 
species are tropical, in this country we have only three 
representatives. In this group the reproductive portion 



6 



KNOWLEDGE 



[Jantjaby, 1904. 



of the funtrus often assumes most fantastic forms, and is 
generally brilliantly coloirred. Over this framework is 
spread at maturity a dingy green, semi-fluid mass, intensely 
sweet to the taste, and, from the ordinary human stand- 
point, intensely fiptid ; the exceedingly minute spores are 
imbedded in this substance, which is greedily devoured by 
various kinds of insects, mostly flies, who thus uncon- 
sciously diffuse the spores, as it has been shown that these 
are not injured by passing through the alimentary tract of 
an insect. It is interesting to note that in certain of the 
fungi the same advertisements in the guise of colour, sweet 
taste and smell, are used for the purpose of unconscious 
dispersion of the spores by insects, as are used by 
many flowering plants for the purpose of securing cross- 
fertilization, also through the agency of insects. 



MODERN COSMOGONIES.* 

VI.— WOllLD-BUILDING OUT OF METEORITES. 

By Agnes M. Cleeke. 

The idea is seductive that we see in everv meteoric fire- 
streak a remnant of the process by which our world, and 
other worlds like or unlike it, were formed. It is not a 
new idea. Chladni entertained it in 1794; and it has 
since from time to time been revived and rehabilitated 
with the aid of improved theoretical knowledge and a 
larger array of facts. Survivals are tempting to thought. 
It costs less effort to realise differences in degree than 
differences of kind. The enhanced activity of familiar 
operations is readily imagined ; while perplexity is apt to 
shroud the results of modes of working strange to 
experience. Hence the presumption in favour of con- 
tinuity ; nor can it be said, even apart from our own 
mental inadequacy, that the presumption is other than 
legitimate. Nature is chary of her plans, lavish of her 
materials. Her aims are characterized by a majestic unity, 
but she takes little account (that we can see) of surplusage 
or wreckage. Now it seems likely that meteorites represent 
one or the other of these two forms of waste stuff. They 
are analogous, apparently, either to the chips from shaped 
blocks, or to the dust and rubbish of their destruction. 
Let us consider what it is that we actually know about 
them. 

It cannot be said that the sources of our information are 
scanty. Fully one hundred millions are daily appropriated 
by the earth as she peacefully pursues her way. Their 
absorption leaves her unaffected. It produces no per- 
ceptible change in her internal economy, and makes no 
sensible addition to her mass. The hundred millions of 
small bodies taken up have, nevertheless, in Professor 
Langley's opinion, an aggregate weight of more than one 
himdred tons.t And this increment is always going on. 
Yet its accumidated effect is evanescent by' comparison 
with the enormous mass of our globe. That it was more 
considerable in past ages than it is at present, might Ije 
plausibly conjectured, but cannot reasonably be maintained. 
Geological deposits contain — unless by some rare excep- 
tion — no recognizable meteoric ingredients. There is 
nothing to show that the earth was subject to a heavier 
bombardment from space during the Silurian era than in 
the twentieth century. 
. Meteorites signify their existence to us, in general, onlv 



* For former articles under this title see KyowiEDGE 1903 
pp. 57, 104, 148, 196, 251. 

■f The Sew Astronomy, p. 197. 



by the bale-fires of their ruin ; but in a few cases its 
actual relics come to hand. Those substantial enough to 
escape total disintegration through atmospheric resistance 
to their swift movements find their way to museums and 
laboratories, where they are subjected to the searching 
investigation demanded by their exotic origin. Its results 
are scarcely what might have been expected. Meteorites 
are not jjeculiar chemicallv : they consist exclusively of 
the same elementary substances composing the crust of 
the earth ; but their mineralogy is highly distinctive. 
They are extremely complex structures, formed, apparently, 
in the absence of water, and with a short supply of oxygen ; 
the further condition of powerful pressure is indicated 
with some probability, nav, with virtual certainty for those 
including small diamonds ; * while prolonged vicissitudes 
of fracture and re-agglomeration are possibly recorded by 
the brecciated texture of many of these rocky trouvailles. 
Their aspect is thus anything but primitive; each fragment 
tacitly lays claim to an eventful history ; they suggest a 
cataclysm, of which we behold in them the shattered 
outcome. The nature of such cataclysms is scarcely open 
to conjecture ; only a hint regarding it may be gathered 
from the circumstance that the most profound terrestrial 
formations are those which appn^ximate most closely to 
the mineralogical characteristics of meteorites. 

Nevertheless, their only ascertained relationships are 
with comets. In every system of shooting stars the 
primary body most probably is, or at any rate was, 
a comet. Each appears to be the offspring of a 
cometary parent, and develops in the proportion of its 
decay. The view has hence been adopted, and not without 
justification, that comets in their primitive integrity are 
simply ''meteor-swarms." Assent may be given to it with 
some qualifications which we ueed not here stop to discuss. 
What immediately concerns us is the interesting question 
as to the constitution of meteor-swarms. What is the 
real meaning of the term ? What does it convey to our 
minds : A meteor-swarm may be defined as a rudely 
globular aggregation of small cosmical masses, revolving, 
under the influence of their mutual attraction, round their 
common centre of gravity. Each must revolve on its own 
account, though all have the same period ; and their orbits 
maybe inclined at all possible angles to a given plane, and 
may be traversed indifferently in either direction. From 
this tumultuous mode of circulation collisions should 
frequently ensue ; but they would be of a mild chai'acter. 
They could not be otherwise in a system of insignificant 
mass, and correspondingly sluggish motion. We are con- 
sidering, it must lie remembered, only cometary swarms, 
as being the only collections of the sort that come, even 
remotelv, within our ken ; and comets include the minimum 
of matter. None of those hitherto observeii. at least, 
whether conspicuous or obscure, newly arrived from space, 
or obviously effete, have occasioned the slightest gravita- 
tional disturbance to any member of our system. 

Eventually, a cometary swarm, if left to itself, would 
probably take something of a Saturnian shape. Colliding 
particles would, owing to their loss of velocity, subside 
towards the centre, and accrete into a globular mass. A 
predominant current of movement would, through their 
elimination, gain more and more completely the upper 
hand ; and it would finally, with the inevitable diminution 
of energy.t be restricted almost wholly to the principal 



* Carbon does not liquefy imder ordinary conditions. In the 
production of his artificial diamonds. M. Moissan employed tremendoos 
pressure and great heat ; but the genuineness of his products has 
lately been denied. — Combes, iloniteur Scientifique, Xovember, 1903, 

t Sir K. Ball, "The Earth's Beginning," p. 243. 



Jakuaky, 1904.] 



KNOWLEDGE. 



{ilane of tlie svsttMii. whicli would thus oonsist of a rotatinrr 
inioleus eni'oinpassfd bv a wido zone of indejiondently 
ciix-uhitiusj metforitos. But tliis mode of dt>velo|iniout is 
not even ap}>roxiinately followed l>v ooinets. It would be 
pt)ssible only if they were isolated in space, and. in point 
of faet. their revolutions roiuid thosuuareof overwhelming 
importanee to their destinies. The suu"s repulsive energy 
eauses theni to waste aud diffuse with expansion of splendid 
plumage. Under the sun's unequal attraction at close 
quarters they are subject to disruption, and the upshot of 
the tidal stresses acting upon them is the dispersal of their 
constituent particles along the wide ambit of their oval 
tracks. 

We are, however, invited to look further afield. C'ometary 
meteor-swarms may be only miniature specimens of the 
contents of space. Why should not remote sidereal regions 
be thronged with similar assemblages, colossal in their 
jiroportions, countless in number? And may they not 
supply the long-sought desideratum of a suitable "world- 
stuff" for the construction of suns and planets? From some 
such initial considerations as these. Sir Norn\an Lockyer 
developed, in 1887, an universal Meteoritic Hypothesis, 
designeil on the widest possible lines, based on promising 
evidenc«, and professing to supply a key to the baifling 
enigma of cosraical growth aud diversification. The 
meteoric affinities of comets formed its starting point ; 
comets were assimilated to nebulw ; and from nebuhe were 
derived, by gradual processes of change, all the species of 
suns accessible to observation. The view was of far-reaching 
import and magnificent generality, but its value avowedly 
rested on a marshalled collection of facts of a special kind. 
In this it differed from the crowd of ambitious speculations 
regarding the origin of things by which it had been 
preceded. In this, it attained an immeasurable superiority 
over them, if only the testimony appealed to could be 
proved valid. Indeed, it is scarcely too much to say that, 
whether it were valid or not, the mere circumstance of 
having called the spectroscope as a witness in the high 
court of Cosmogony constituted an innovation both 
meritorious and significant. 

The spectrum of the nebula; was a standing puzzle. A 
theory which set out by making its meaning plain secured 
at once a privileged position. This was seemingly accom- 
plished by Sir Norman Lockyer through the means of 
some simple laboratory e.xperiments on the spectra of 
meteorites. Certain "low temperature" lines of magnetism 
given out by the vapours of ston}' aerolotic fragments 
were shown to fall suspiciously close to the chief nebular 
lines previously classed as " unknown." The coincidences, 
it is true, were determined with low dispersion, and were 
published for what they were worth ; but they looked 
hopeful. Their substantiation, had it been possible, 
would have marked the beginning of a new stadium of 
progress. Nature, however, proved recalcitrant. The 
suggested agreements avowed themselves, on closer enquirj', 
as approximate only ; magnesium-light makes no part of 
the nebular glow, and nebulium, its main source, evades 
terrestrial recognition. The light of cosmic clouds is, in 
fact, gui yeneris ; it includes no metallic emissions ; while 
the fundamental constituents of meteorites are metals 
variously assorted and combined. 

The decipherment of the nebular hieroglyphics was the 
crucial test ; its failure to meet it left the hypothesis 
seriously discredited ; for coincidences between spectral rays 
common to nearly all the heavenly bodies naturally counted 
for nothing. Yet the investigation had its uses. The energy 
with which it was prosecuted, the ingenuity and resource 
with which it was directed, told for progress. There has 
been a clash of arms and a reorganisation of forces. 
Thought was stirred, observation and experiment received 



a strong stimulus, fresh affluents to the great stream of 
science began to be navigated. Efforts to prove what had 
been asserted wert> fruitful in some directions, and the 
work of refutation had inestimabUi value in defining what 
was ailiuissible, aud establishing unmistakable landmarks 
in astrophysi('S. 

The discussion, however, threw very little light on the 
part played by m(>teorites in Cosmogony. Their world- 
building function remains largely speculative. Doubts of 
many kinds qualify its possibility, and lend it a fantastic 
air of unreality. 15ut this may in jiai't be due to a defect 
of imaginative power with which the universe is not con- 
cerned. 

Waiving, then, i>reliiuinary objections, we find ourselves 
confronted with the essential (piestion : Given a meteor- 
swarm of the requisite mass and dimensions, is there 
any chance of its coiulensiug into a planetary system ? 
Sir Norman Lockyer sot aside this branch of his suliject. 
His hypothesis was in fact " pre-iu^buhxr." He assumed 
that the small soli<l bodies with which it started would, in 
course of time, become completely volatilised by the heat 
of their mutual impacts, and that the resulting ga.seous 
mass would thenceforward comport itself after the fashion 
prescribed by Laplace. Professi>r Darwin regarded the 
matter otherwise. It seemed to him possible to combine 
the postulates of the meteoric and nebular theories in a 
system planned on an original principle. F'or this purpose 
it was necessary to excogitate a means of rendering the 
kinetic theory of gases availabh; for a meteor-swarm. 
" The very essence," he wrote,* " of the nebular hypothesis 
is the conception of fluid pressuris since without- it the 
idea of a figure of equilibrium becomes inapplicable." 
M. Faye abandoned this idea; he built up his planets out 
of incoherent materials, thereby avoiding the incongruities, 
but forfeiting the logical precision, of Laplace's stricter 
procedure. Prof. Darwin consented to forfeit nothing; he 
stood forward as a syncretist, his object being to " point out 
that by a certain interpretation of the meteoric theory wo 
may obtain a reconciliation of these two orders tif ideas, and 
may Injld that the origin of stellar and planetary systems 
is meteoric, whilst retaining the conception of fluid 
pressure." For the compassing of this end, he ado[>ted a 
bold expedient. Fluid pressure in a gas is " the average 
result of the impacts of molecules." Fluid pressure in a 
meteor- swann might, he conceived, be the net product, of 
innumerable collisions lietweeu liodies to be regarded as 
molecules on an enormously inagiwAed scale. The sup- 
])osition is, indeed, as Kepler said of the distances of the 
fixed stars, " a liig ])ill to swallow." From molecules to 
meteorites is a long leap in the dark. The machinery of 
gaseous impacts is obscure. It can be set in motion only 
by ascribing to the particles concerned properties of a 
most enigmatical character. These i>articles are, however, 
unthinkably minute ; and in sub-sensible regions of 
research, the responsibilities of reason somehow become 
relaxed. We are far more critical as to the behaviour of 
gross, palpable matter, because experience can there be 
consulted, and is not unlikely to interpose its veto. 
Meteorites are (hjubtless totally dissimilar from molecules, 
however many million-fold- enlarged ; and they would 
infallibly be shattered by collisions which only serve to 
elicit from molecules their distinctive vibrations. More- 
over, the advance of the shattering process would admit- 
tedly end the prevalence of fluid pressure. So that the 
desired condition, even if initially attained, would be 
transitory. There is, besides, a ra<lical difference between a 
group of bodies in orbital circulation and a collection of 
particles moving at hap-hazard, unconstrained by any 

* Proceedingn of the Rot/al Society, Vol. XIV., p. i. 



8 



KNOWLEDGE. 



[January, 1904. 



predominaut law of force. Professor Darwin's paper thus 
stands out as a monument of in«,'enious niathematieal 
treatinieint applied to an ideal state of things. 

An aggregation of revolving meteorites has no figure of 
eqailihrium ; and it is through the consequences neces- 
sarilv resulting from this property that mathematicians 
are enabled to trace the progressive changes of a rotating 
fluid mass. In the absence of any such direct means of 
attack, their position regarding the problem presented by 
an assemblage of flying stones is not much better than that 
occupied by Kant, face to face with an evolving universe. 
It seems, however, clear that a meteor-swarm can condense 
only through the effects of collisions among its con- 
stituents. When the irregularities of movement upon 
which their occurrence depends are got rid of, the 
system must remain in statu quo. Order makes for 
permanence ; a tumultuary condition is transient. The 
eventual state of the system can, however, be no 
more than partially foreseen. Bodies arrested in their 
flight should fall inward ; hence a central mass would 
form and grow ; but the production of planets would 
seem to be conditional upon the existence of primitive 
inequalities of density in the swarm. These might serve 
as nuclei of attraction for meteoric infalls, not yet com- 
pletely exhausted, but plying with harmless fire one at 
least of the globes they helped to shape. There could, 
indeed, on this showing, have been no such harmonious 
succession of events as constituted the predominant chanu 
of Laplace's scheme. The planets should be supposed to 
have issued pell-mell out of a chaos ; or, rather, the chaos 
should have contained frona the beginning the seeds of a 
predestined cosmos. Its evolution would have been like 
that of the oak from the acorn, an unfolding of what was 
already essentially there. And it may be that at this stage 
of penetration into the past, the unaided human intellect 
meets its ne plug ultra. There is a vital heart of things 
which we cannot hope to reach. Thought instinctively 
pauses before the vision of the symbolical brooding 
Dove. 

To resume. Meteoric cosmogony deserves serious con- 
sideration. Materials for the purpose probably exist 
abundantly ; and, in the solar system at least, they must 
have been formerly much more abundant than they now 
are. The earth has been raking up meteoric granules 
by hundreds of millions daily during untold ages, and her 
zone of space is still very far from being swept clean. The 
persistence of the supply, however, may be occasioned by 
the continual aiTival of reinforcements from interstellar 
realms. Comets appertain to, and travel with the sun's 
cortege ; and this is also inevitably true of comet-born 
meteors. But a multitude besides circulate independently 
of comets, and with much higher velocities. Their orbits 
are then hyperbolic ; they belong to the ca,tegory of 
" irrevocable travellers," and their capture provides us 
with genuine samples of sidereal matter. Universal space 
must contain them in vast numbers, yet there is nothing 
to prove their collection into swarms. The spectroscope 
supplies no assm-ance to that effect ; it has given its verdict 
against the meteoric constitution of nebulse and temporary 
stars. And if we admit, under the compulsion of minera- 
logical testimony, that the aerolites so strangely landed on 
terrestrial soil are really the drbria of ruined worlds, we 
can see for them no chance of restoration. Solitary they 
are, even if they occasionally pursue one another along an 
identical track, and solitary they must remain. Bodies do 
not of themselves initiate mutual circulation. Planetary 
or stellar outcasts cannot become re-associated into a 
gravitational system. Of a cosmic swarm, as of a poet, it 
may be said, Nascitur, non jit ; and their birth-secret is 
undivulged. 



JUPITER AND HIS SURFACE CURRENTS. 

By the Eev. T. E. E. Phillips, m.a., f.e.a.s. 

The general aspect in the telescope of the planet Jupiter 
is well known. His markedly elliptical disc, which is 
distinctly brighter in the centre and gradually fades off 
towards the limb, is traversed by a series of dusky belts 
which vary from time to time both in width and position. 
These Ijelts frequently show great irregularities at the 
edges, being broken up or indented by a number of light 
and dark spots, while dusky wisps are often to be seen 
projecting from them across the bright zones which 
separate them. The accompanying drawings will serve to 
illustrate the general arrangement of the surface features 
and also the great and rapid changes of aspect to which 
they are subject. Thus it will be seen from the illustra- 
tions that in" the years 1896 and 1898 (Figs. 1 and 3)— as 
was also the case in 1901 and 1903 — the belt lying North 
of the equator was quite narrow, b>it that at other times 
it was broad, and exhibited numerous condensations and 
white spots at its edges. It not infrequently happens that 
the general aspect of the planet undergoes a marked 
alteration even in the coiu-se of a single apparition. 
Thus Fig. (> represents a view of Jupiter in June, 1902, 
but l>y the latter part of the autumn the appearance of 
the disc had materially changed. The equatorial regions 
were intensely white — a very striking contrast to the rich 
warm coppery tone which was so marked a feature of the 
planet a few years ago — and the whole of the disc North 
of the N. temperate belt was deeply shaded with a delicate 
bluish grey. 

It is probable that some of the changes on Jupiter are 
of a cyclical or seasonal character. Mr. A. Stanley 
Williams in a valuable paper communicated to the Eoyal 
Astronomical Society in April, 1899, showed from a 
discussion of a large number of observations extending 
over many years that there is a remarkable variation in 
the colour of the two principal equatorial belts. Thus, 
when the S. equatorial belt is at a maximum of redness, 
the N. equatorial belt is at a minimum, or even bluish in 
tone, and vice versa. The mean period of these variations 
is found to be about twelve years, and as this corresponds 
\vith the length of a sidereal revolution of Jupiter round 
the sun, it is probable that the change observed is of a 
seasonal character. The maximum redness occurs soon 
after the vernal equinox of the particular hemisphere in 
which the belt exhibiting it is situated. In accordance 
with the interesting conclusion at which Mr. Williams 
has arrived, the N. equatorial belt has lately been in- 
tenselv red, and the S. equatorial belt almost colourless, 
except in the region immediately following the Eed Spot 
bay. 

JBut, perhaps, the most interesting and instructive 
feature hitherto observed in connection with Jupiter is 
the difference of speed with which his spots and other 
markings are drifting. So long ago as the latter part of 
the 17th centuri-, Cassini found that the markings in the 
neighbourhood of the equator performed a rotation in 
nearlv six minutes less time than was required by objects 
further north and south. Sir William Herschel, Schroter, 
and other observers confirmed this result, but as the 
outcome of the labours of more modem investigators, a 
considerable number of distinct currents are now known 
to control the movements of Jupiter's surface material. 
There can be no doubt that many recorded changes on 
Jupiter are in reality due to the great proper motions of 
the objects observed, which quickly cause them to become 
relatively displaced. 



r 1 ^ ' 1 


m 1 1 ■ 


1 ' 'I ' 1 


L 1 ' 


1 ^ 



..\, 



W 
H 

Oh 
O 



a 



i<3 .- 



;i 



6 








H 

5 






Janiaby, 1904.] 



KNOWLEDGE. 



With one or two exceptinns these surface cuvrciits are 
pretty constaut. Their velooily varies within eertaiu 
limits, and the hititude of their liouiichiiies is not always 
the same, but whenever detinite sj.H>ts or observable 
oondeusations appear their niovenieuts of rotation are 
nearly always found to conform more or less closely to 
the normal s]>eed of that latitude. In an article in the 
February. 1;10:5, uuuiber of PopnJar AstniiiDitiii, Prof. 
G. W. Houijh questions the existence of several of these 
surface currents. Consideriufr. however, the great mass 
of existing: evidence. I venture to thiuli that his conclusion 
is altogether unfounded, and that the reality of the 
currents is lieyond dispute. In January, 189ti, a valuable 
pajier bv Mr. A. S. WilUanis was published in the 
Monthly' Notlceg, E. A. S., "On the Drift of the Surface 
Material of Jupiter in Different Latitudes." In that 
paper Mr. Williams brought together the results of 
numerous eminent observers in various years, and gave a 
cleaj" account of nine separate and distinct ctirrents. It is 
worthy of m>te that the .arrangement of these currents, 
unlike those of the sun, is by no means symmetrical, neither 
is that of the two hemispheres the same. Moreover, the 
N. hemisphere contains in contiguity the swiftest and the 
slowest that have yet been observed. 

The following table shows the general arrangement of 
these surface currents, but it must be understood that. 
both the limiting latitudes and the rotation periods are 
subject to certain variations : — 



No. 



Latitude. 



Rotation 
Period. 



Kemarka. 



1 I +80° to +31° 

2 I +J4'' to +2*° 



b. m. s. 

9 55 37-5 

f9 ot .30 ) 

1 9 56 30 ( 



From Polar Eesious to N.N. Temp. Iielt. 
From N.N. Temi). belt toN. uoiiiponent 
of N. Temi). holt. 



3 


+21° to +20° 


[? 


48 
49 


30 J 


S. component of N. Temp. belt. 


4 


+ 20° to +10° 


9 


54 


32 


N. Trop. zone and N. side of N. Eqna- 
torial Ijelt. 


5 


+ l<i° to-12« 


9 


50 


20 


Great Equatorial Current, conjprisinc 
S. portion of N. Equatorial belt, 
Equatorial zone, and N. component 
of S. Equatorial I.elt. 


6 


-12° to -lt° 


9 


51 


SO 


Spots in briiflit rift dividing S. Equa- 
torial belt. 


7 


- 12° to -18° 


9 


55 


40 


S. component of S. Equatorial belt. 


8 


-14° to-2'?> 


9 


.=» 


37 


Great Ked Spot. 


ti 


- 18° to - 36° 


9 


.55 


18-5 


From S. Trop. zone to S. Temp. zone. 


10 


-30° to -50° 


9 


55 


6 


S.S. Temp, belt, and bright zone S. of it. 


11 


- .^iJ" ± 


1( 


4o 


23 


Ed^re of S. Polar sbadinf^. 



These cun-ents must be discussed more in detail. 

No. 1. — There appears to be some uncertainty as to how 
far north this current extends. In 1888 and again in 18!<2, 
Mr. Williams observed dark streaks which extended into 
very high N. latitudes and moved in accordance with the 
tabulated velocity. Since then Captain P. B. Mt>lesw()rtli, 
who has made quite a unique series of .Jovian observations 
under very fine seeing conditions in Ceylon, Las succeeded 
in detecting a number of light and dark spots and streaks 
in the Polar regions. Amongst these, he found in I!t(»l five 
dusky streaks in about latitude •jO"', which gave a mean 
period of 9b. .56m. 37s. It is cjuite jjrobal)Ie that tb(> 
surface drift in these regions may be variable from year to 
year. More observations are much needed to settle tiie 
question of the minor, and at present doubtful, currents on 
the surface of Jupiter. 

No. 2. — The drift in this region is not constant. At 
times when the N. hemisjjhere is in a state of disturbance 
spots are liable to appear which have a decidedly rajiid 
rate of motion. As a general rule, however, it is found 
that markings in this neighbourhood exhibit the slowest 
movement of any on the disc. 

No. 3. — This is unquestionably the most remarkable, as 



it is the swiftest, of all the .Jovian currents. Our know- 
ledge of it has been well summavized by Mr. \V. V. 
Denning in a ]>aper eutitleil " On a i'l-obabie Instance of 
Perioilically Kccuirent Disturbance on the Surface of 
Jupiter," published in huiithlij Notices, K. A. S., Dccemlior, 
1898. It ajipears that at intervals of little more than ten 
years spots hav<' fi-ecpiently ajipcared on the S. side of the N, 
temju'rate belt which have exhibited a velocity whicii is 
extraordinary. As already pointed out, this swift current 
exists si<h^ by sidt^i with the slowest of the disc (No. 2), and 
taking their extreme v.ilues the dii3'erence of velocity 
amounts to about ^t!.') miles per hour. It was thought 
that another outbreak of these rapidly-moving spots would 
occur at the end of 1900 or beginning of 1901. Unfor- 
tunately no such occurrence was observed, but it is quite 
possiljle that spots may have appeared and escaped 
tietection, as in December, 1900, the planet was in con- 
junction with the sun. 

No. 4. — This— commonly known as the N. Tropical 
Current — is another of the most important of the Jovian 
currents, and is generally in evidence. In some years 
when theN.e(|uatorial l)elt is narrow, a number of dark s])ots 
are seen quite detached from this belt (see Figs. 1 and :5), 
and in 189S and 190;! these were connected by a fine narrow 
line like beads strung on a thread. This narrow line is shown 
in Fig. 3 starting from one of these spots. On other 
occasions the N. etpiatorial belt extends so far north as to 
include this region, but it is found that the spots at its 
edge, which are often very numerous and detinite, conform 
to the normal velocity of the N. Tropical Current, even 
though the S. edge of the belt l)e drifting at the same 
rate as the equatorial zone. I have given 9h. .5.5m. :12s. 
as the rotation period of this region, but it frecjuently 
happens that spots exhibit a period very cousideralily 
longer than this, and also very considerably shorter. A 
remarkable diversity of speed was apparent in this 
current in 1899. In that year I received a large number 
of transit observations of N. tropical spots from several 
observers, so that an ample amount of material was 
available for discussion. 1 had previously found from 
observations secured comjiaratively early in the apparition 
that a dark spot — shown in Fig. 4 lyiug in a distinct bay 
on the N. sidi^ of the N. equatorial belt — was moving at an 
altogether abnormal rate, but when the whole of the 
materials to h.and were charted and examined, it was 
found that the spots between longitudes 140" and 260'^ 
had a mean rolatiou period of 18'.5 seconds less than that 
of the remainder of the current. The exact values were 
91i. .5.5ni. 1.5'3s. and 9h. 5.5m. 3;J'9s. respectively. So far 
as I am aware so rapid a drift as that indicated by the 
former value has never been observed in this latitude 
before. Further, it w'as noticed that the limits of longitude 
which ineludeil this swift rotation were constant during 
the [leriod covered by the observations. Spots starting 
from X 2<)0° quickly hurried forward, and rapidly-moving 
spots on arriving at A 140" suddenly slowed down. A full 
account of this remarkable disturbance will be found in 
inv paper on "The Extra-Equatorial Currents of Jupiter 
in 1899," jiublished in Monthli/ Notices, R. A. S., January, 
1900. 

No. .5. — We now come to the Great Equatorial Current. 
The northern boundary of this current is variable. When 
narrow the whole of the N. equatorial belt ajipears to be 
included within its limits, but at other times only the 
southern component, or possilily the whole of the belt may 
lie without it. At any rate, spots near the N. limit of 
the /.one frequently exhibit a period a few seconds longer 
than those at or near the N. edge of the S. equatorial 
belt. It is to these latter that most of the determinations 
of velocity in previous years refer. It is worth noticing 



10 



KNOWLEDGE 



[jANUARy, 1904. 



Number of Spots 
observed. 


Rotation 


Period 




h. m. 


s. 


19 


9 50 


24-2 


34 


9 50 


24-7 


26 


9 50 


237 


24 


9 50 


28-6 


24 


9 50 


27-8 



that in 1879 the period was only about Oh. 50m., but, 
subsequently, increased steadily to 9h. 50m. 3(:ls. in 1896. 
Since then "the value has again declined, a sudden drop 
liaving been followed by somewhat irregular variations. 

The following are the periods which I have found from 
a discussion of my own observations during the past few 
years : — 

ITear. 

1898 
1899 
1900 
1901 
1902 

A remarkable feature of the Great Equatorial Current is 
found in the peculiar wanderings or oscillations of the 
spots on each side of their mean or com]nited positions ; 
and it frequently happens that a whole grou]i of spots will 
share these vagaries of motion together. Despite these 
wanderings, however, there can be no doubt that many of 
the equatorial spots remain visible for long periods of 
time, but the fact that the planet is lost in the sun's rays, 
so far as satisfactorv oliservations are concerned, for at 
least three months about the time of his conjunction — to 
say nothing of the difficulties caused by irregularities of 
motion and changes of form in the spots themselves — 
mal;e their correct identification from year to year almost 
impossilile. 

No. 6. — A bright rift is usually seen to divide the 
S. equatorial belt into two separate components. During 
the last few years Captain Molesworth lias followed a large 
number of bright spots in this rift, wliich appears to form 
a kind of transition stage between tiie two well-knowu 
periods of 9h. 50m. + and 9h. 55m. +. His rates for 
1900 and 1901 are 9h. 51m. 37-3s. (from 17 spots) and 
9h. 51m. 32-2s. (from 20 spots) respectively. 

No. 7. — On the occasions when markings on the S. com- 
ponent of the S. equatorial belt have been observed and 
followed, it has been found that their period differs but 
little from the contemporary period of the Great Red Spot. 

No. 8. — This can scarcely be called a current, as the 
surface material referred to under this heading is con- 
fined within the limits of the Great Red Spot. This 
remarkable object was detected in 1878 by M. O. Lohse, 
of Potsdam (who appears to have been the first to 
draw it), and by Professor Pritchett, of Missouri, and 
Mr. Dennett, of Southampton (whose observations seem to 
have been the earliest j^ublished), and quickly attracted 
general notice. Nearly every telescope was directed to 
its observation, and its behaviour carefully watched. 
It is elliptical in shape ; its dimensions being about 
27,000 miles in length, and nearly 9000 in breadth. 
What the nature of the spot may be it is impossible at 
present to say. Certainly it cannot be regarded as a solid 
feature of the planet's globe, since it is by no means stable 
in position ; but, on the other hand, there can be no doubt 
that it is the product of forces which have considerable 
permanence, and, judging from the very definite and 
regular appearance of the well-known hollow or bay on 
the S. side of the S. equatorial belt in which the Red Spot 
lies (see Pig. 6), despite the present faintuess of the spot 
itself, as yet show no signs of declining energy. A very 
interesting account of the early history of the Red Spot 
will be found in two valuable papers by Mr. Denning in 
the supplementary numbers of Monthly Notices, R. A. S., 
1898 and 1899, and also in his article in this journal for 
August, 1902. In these papers Mr. Denning connects the 
present spot and hollow in which it lies with the ellipse 
seen by Mr. Gledhill in 18()9, and with numerous similar 
objects which have appeared iu the southern hemisphere 



at intervals since 1831. Indeed it is quite possible that 
the Red Spot of to-day may he identical with the remark- 
able object discovered by Dr. Hooke.-so long ago as 1664. 
The determinations of the rotation period have been very 
numerous. Mr Denning, from a careful examination of 
existing material, and assuming his identifications to be 
correct, finds that in 1831 the period was 9h. 55m. 33-3s., 
that it increased to 9h. 55m. 38'3s. in 1859, again declined 
to 9h. 55ni. 334s. in 1877, and once again increased to 
9h. 56m. 41-9s. in 1899. In 1900 the rotational velocity 
exhibited a slight increase; in 1901 the spot remained 
almost statiouarv in longitude (as based on the period of 
9h. 56m. 4063s., adopted by Messi's. Marth and Crommelin 
as the value of their zero meridian of System II ) ; and 
iu 1902 — from a discussion of about 100 transit observa- 
tions of the spot and hollow secured by various observers — 
I find the period of the object to have been r-edueed to 
9h. 66m. 39-3s. It should be added that the spot, in addition 
to its oscillations in longitude, like so many of the markings 
on the planet, has also a motion in latitude — the extreme 
drift being about 4000 miles. The deep red tone which 
distinguished the spot at the time of its appearance in 
1878 soon proved evanescent, and the object is now but a 
ghost of its former self. In some years it has appeared 
merely as a faint elliptical ring ; at others, the whole has 
just been visible as a feeble dusky stain on the bright zone 
in whi(_'h it lies. Possilily it may lie dimmed by the over- 
lying vapoiu's, but. as already stated, there is no reason to 
sujipose that the forces which produce it are on the wane, 
and we may yet hope that at some future time it will 
reassume its former glory. 

No. 9. — This is unquestionably the steadiest and most 
uniform of all the .Jovian currents. It was detected by 
Schriiter so long ago as 1787, since which time it has 
shown practically no variation. It extends over quite a 
broad zone, emliracing the region between the S. edge of the 
S. equatorial belt, and the N. edge of the S.S. temperate 
belt. Observers of Jupiter will remember the remarkable 
S. tropical mass of dark material — extending eventually 
over about 90° of longitude — wliich swept round the S. 
side of the Red Spot during the summer of 1902. 

No. 10. — This rapid current so far south is remarkable. 
It appears to be fairly constant and uniform, but has 
nothing in a similar latitude to correspond with it in the 
northern hemisphere. 

No. 11. — In 1901 Captain Molesworth detected a number 
of dark objects at the edge of the N. polar shading. These 
did not share in the rapid drift of the Great Southern 
Current (No. 10), but moved appi'oximately at the 
tabulated rate. More observations are needed to establish 
the constancy of this current. 

But interesting as is the investigation of these surface 
currents, the real nature of Jupiter's physical condition is 
the problem which students of the planet must endeavour 
to solve. It has generally lieen agreed that the belts and 
spots of Jupiter are of the nature of clouds and atmospheric 
vapours, that the true globe of the planet has never been 
seen ; and that its real rotation period is consecjuently 
unknown. But whatever view may be adopted as to the 
vaporous character or otherwise of the visible features of 
the disc, it is pi\>bal)le that the internal liody of the planet 
rotates iu a period somewhat longer than any markings we 
can observe — possibly in a period just a minute or so less 
than 10 hours. As regards the relative altitudes of the 
various markings, there seems good reason to suppose that 
the more swiftly moving objects are situated at a greater 
height than those which move more slowly. Of course, it 
must be remembered that the planet may have no solid or 
definite surface divided off from the vapours which form 
its belts and spots. It is highly probable^beariug iu 



January. 1904.] 



KNOWLEDGE. 



11 



uiiud the very low density of Jiipiter^tliat the whole 
globe is still in au intensely heated, semi-moUcu and 
viseous couditiou, and that what we see is but the outer- 
U'.ost shell of visible material. Professor Hough, in his 
important and valuable paper already ivferred to, suggests 
that the visible lx>uudary of Jupiter has a density of al)out 
oue-half that of water, is of the nature of a liquid, and 
that in it are immersed the Ked S]H)t and otliers wliose 
motion in longitude and latitude are slow and gradual, and 
whieh are tolerably permanent or long enduring. Ho 
considers that the equatorial and other belts-may be at the 
surface of this liquid or at a higher level than the Red 
Spot, and that the equatorial regions may Ix' concealed 
by overlying vapours at a much greater altitude, iu wliich 
openings and iiregular condensations give rise to the 
ap)>earance of white and dark spots. 

No doubt there are many interesting questions iu con- 
nection with Jupiter of whieh the solution must be left 
for future students ; but this much, at any rate, we may 
suggest with some contidenee : — We look at Mars and our 
own satelUte. iu them we see a forecast of physical con- 
ditions to which some day the eiirth must at least approxi- 
mately attain. We look at Jupiter, and, in the constant 
agitation of his heated glolje, we catch a glimpse, though 
on a giant scale, of our own world in the dim recesses of 
the j>ast. 

The accompanying diagram will enable the reader to 



5 STcmperaIn Zone 
5 TempcraJe Zone 
5 Tropical Zone 



Equatorial Zone 



N. Tropica I Zone 
U Temperate Zone v- 
N N. Temperate Zone ^ 




S Polar Shadinq 
.^ S.Temperate Belt 

^S.Tefnperate Bell 

SEquatonal Bell 

Equatorial Band 
N Equatorial Belt 

N Temperate Bel I 
N N Temperate Bell 

N Polar Shading 



identify the various features referi'ed to iu the above 
article and depicted in the illustrations. 



THE SHOWER OF LEONID METEORS IN 1903. 

By W. F. Denning, f.r.a.s. 

Tejipel's comet (1S66 I.) and the dense swanu of meteors 
in its contiguous region having passed through perihelion 
unobserved in 1899 the prospect of a fine shower of 
Leonids in 1903 appeared very doubtful. The meteors 
being, however, pretty thickly distributed along a con- 
siderable extent of the orbit, a fairly active recurrence of the 
shower was thought to be quite possible. Those oljservers 
who watched for its return on the morning of November 
Ifi realised their best expectations. The Leonids were 
aljuudantly presented, offering the test meteoric spectacle 
observed in England since 1885, and forming the prototype, 
if far from being the parallel, of the grand exhibitions of 
1799, 1833 and 1866. 

The following are brief extracts from observations on 
the night following November 15, which have either been 
published or jirivately communicated to the writer : — ■ 

Backhouse, T. W., Sunderland. — Between 17h. 44ra.and 
18h. 5m., about 83 meteors per hour. A Leonid fireball 
seen at 15h. 49m. The Leonids were bright generally. 



Of 65 recorded, 1 being = Veuus, -i = Jupiter, 15 = Sirius, 
and 26 brighter than, or equal to, 1st miguitude stirs. 

BrooJ:, C.L.,Miltliam, near Hitddcrsfiehl. —Btitwd'n \-2\\. 
and 15h. 30m., 52 Leonids were seen, after wliich clouds 
interfered. Verv brilliant Leonid at 13h. .59im., 2 x +. 
shot from 137'."" -^ 8^" to 133' ± 0'. Radiant of shower, 

Corder, 11., Bridijwaler. — Between 17h. and 18h., about 
200 meteors per hour. Estimated position of radiant, 
149= + 22". 

Cruee, W. de, E.teter. — Between 16h. 25ni. and 17li. lOiii., 
108 meteors observed. 

Dennimj, W. F., Brislol.—The disphiy watched between 
12h. and 18h. 15m. Maximum, 17h. 30m. to 17h. 45ni. 
42 meteors. Radiant, 151° -|- 22=, about 6 degrees iu 
diameter. 

Ellison, Rev. W. F. A., Enniacortlnj.—lUi. 45iii. to 
12h. 45m., 5 Leonids; 12h. 45m. to 13h. 45m., 16 Leonids; 
13h. 45m. to 14h 45m., 36 Leonids; 14h. 45m. to 151i., 
11 Leonids; loh. to 15h. 15m., Leonids! Three fireballs 
seen, 13h. 40m., 153' + 43° to 185' + 28° (Taurid) ; 
13h. 58m., 160=" + 18° to 166° + 12° (Leonid) ; and 
14h. 19m., 210' -|- 65° to 273° + 58P (Leonid). 

livyal Observatory, Greenwich. — About 150 meteors seen, 
some as bright as Venus, the most prolific time being 
about IBh., wiieu they appeared at the rate of 100 j^er 
hour. 

Ilenrij, J. B., Duhliii.—h'J Leonids seen in 15 minutes 
preceding 15h., and 20 in 15 minutes following that hour. 
Between "leh. and 17h. 30m. observer had the impression 
that meteors were appearing at the rate of from 200 to 
300 per hour. 

Herschel, Prof. A. S., Slotigh.— Not much short of 200- 
250 meteors per hour. Brilliant Venus-like meteors 
observed at 16h. 31m., 17h. 33m., and 17h. 41m. 

Horner, Maiires, Taploiv.—THmng last hour of darkness 
counted S6 meteors, nearly all of which were Leonids. 

Johnson, Kev. S. /., '7?r((//./orf.— Several hundreds of 
meteors with the usual Leouid streaks and swift moUons 
must have passed across the whole sky. 16h. 27 \m., 
Leonid equal to Venus, 192° + 13° to 195° -|- 10'. 

KniijU, G. M., Lo/«/<v«.— Novemlier 14-17, 217 Leonids 
registered at Hauipstead. Five fireballs seen with streaks, 
indicating radiant at 149V° -f 23°. Maximum 171i. 3iim., 
November 15. 

Kinij, A., ShetHeld. — 17h. 57m. to 18h. 3m., 18 Leonids. 
Hourly rate, about 200. Radiant, 148' + 22°. 

Milliyan, W. //., County !><>(';«.— Apparent maximum, 
14h to 16h., with horary rate of 80 to 100 for one observer. 
Radiant, 149° + 22°. 

MrlLini, John, Lishurn.—Vih. 20m. to 14h. 20m., 20 
Leonids, large proportion 1st magnitude; 13h. 45m., vivid 
green fireball from Taurus, 103° ± 0° to 112' - 6'. 

Moffat, A. G., Swansea.— Idh. 30m. to 18h., a brilliant 
display of large meteors ; some green-coloured, the major 
portion, however, electric blue. 

Service, R., Dumfries.— ISh.dOm. to 19h., 42 Leonids 

observed. 

Thonipson, G. C, CacfZi/f'.— Watching with a friend for 
several hours, only about 25 Leonids were seen ; a number 
of other meteors radiated from Auriga. 

Wriijht, F. H., Northamj)ton.—lbh. to 15h. 3Uui., 30 
meteors; 15h. 30ia. to 16h., 60 meteors ; afterwards counted 
about 3 or 4 per minute. Maximum at about 17h. I3m., 
near which time 8 or 10 were several times counted in one 
minute, and 5 or 6 visible in the sky at the same instant. 

The general results may be summarized as follows :^ 
Time of maximum, November 15, 17h. 40m. 
Rate of apparition, 4 per minute for one observer. 



12 



KNOWLEDGE, 



[January, 1904. 



Point of radiation. loD^ + 22^°. 

Character of meteovr--, bright generally, with streaks 
and swift motions. 
Several Leonids and meteors belonging to contemporary 
minor showers were doubly observed, and their real paths 
have been computed. Among the latter there was a 
Taurid fireball, seen on November 16, about loh. 42m.. at 
Enniscorthy and Lisburn. It passed over the S.E part of 
. Anglesea at heights from 72 to 32 miles, with a velocity oF 
23 miles per second. Radiant at 61 + 24^ A 2ud 
magnitude meteor appeared on November 15, loh. 59m.. 
directed from a radiant at 113° — 34^ and descending 
from 64 to 48 miles along an extended course of about 142 
miles from over Sussex to Lincoln. Velocity about 19 miles 
per second, but the flight of the meteor seemed much 
retarded by atmospheric resistance, and at the end of its 
visible career, as observed at Bristol, it became almost 
stationary, its material and momentum being apparently 
quite exhausted. 



Hcttrrg. 

[The Editors do not hold themselves responsible for the opinions 
or statements of correspondents] 

> 

LARGE VERSUS Sil.lLL TELESCOPES IX 
PLANETARY WORK. 

TO THE EDITORS OF KNOWLEDGE. 

Sirs, — In the course of his interesting article on Saturn 
in the current number of Knowledge, Mr. W. F. Denning 
has referred to the well-known fact of large telescopes 
sometimes failing to show faint planetary markings that 
were visible in those of much smaller aperture. The 
mirkings in question usually appear to be those having a 
considerable apparent area and a more or less diffuse and 
indefinite outline, and I do not remember to have ever 
seen anv demonstration, either theoretical or practical, why 
markings of this nature sh'juld be any jdainer or better 
seen as a whole in a large telescope than in a small one. 
As regards minute details there can, however, be no 
question as to the superiority of the large telescope. 

But my present object in writiuor is to draw attention 
to the fact that the remarkal)le and instructive experi- 
ments on artificial markings, details of which have been 
recently published, seem to have an intimate bearing also 
on this question of the failure of large telescopes to show 
planetarv- markings visible in smaller ones. Particulars 
of one of these experiments having a special bearing on 
the sul)ject, made by Mr. and Mrs. Maunder, have been 
recently published in the Journal of the British Astrono- 
mical Association, Yol. XIIL, page 349. In this experi- 
ment two waved parallel lines when viewed at a distance 
of 130 feet, gave rise to the appearaace of a faint, diffused 
t)and. On approaching nearer, the experimenters found, 
to their evident surprise, that this appearance after awhile 
began to get feeble, and finally disappeared aUoijether at a 
distance of about 100 feet. Nothing could then be seen 
at the place of the two waved hues until approach had 
been made to very nearly 60 feet, when the lines rapidly 
became distinct. 

Now the employment of a larger aperture, and probably 
higher power, woidd no doubt be analogous in its effect to 
a diminution in the distance of the object, and hence, even 
assuming all other things to be equal, it does not seem 
diflicult to conceive the existence of a jiarticular kind of 
mai-king that would give rise to a distinct irapressiim in a 
small telescope, although nothing whatever could be seen 
at the same place with a large one. For instance, a number 
of faint, irregular, naiTow streaks crossing the bright 



equatorial zone of Saturn, perhaps analogous in their 
nature to the well-known equatorial "wisps" of Jupiter, 
and corresponding to the waved lines of the experimeut, 
might give rise to an appearance of alternate faint and 
dark areas or spots in a small telescope, though a " giant" 
telescope might fail to show anything whatever of this 
ap]:iearance. Yet such apparent markings or spots, 
although not strictly objective, would clearly have an 
objective basis, and heuce they would be suitable for 
determining the rotation period. 

A. Stanley Williams. 
Hove. 10 j3, December 1. 



THE ORCHID CEPHA.LANTBERA GRANDIPLORA. 

TO TBE EDITORS OF KNOWLEDGE. 

Sirs, — I have long had a thing to say about the 
fertilization of Cephilaufhera yrandifiora. and now that 
Mr. Praeger's hiterestinij article on Orchids has appearei 
dim't think I could fit it with a better time. 

Figs. 1 and 2 represent respectively the front and side 
views of the column of this plant, and are drawn from life. 
What are the threads that cross and re-cross and attach 
themselves not ouly to the stigma but to the front of the 
column and sides of basal portion of labellum, like the 
supporting strands of a spider's web r IE they are pollen 




Fig. 1. 



Fig. 2, 



tubes, why the cui-ious reticulation ? At first I thought 
the meshes were caused by pollen grains falling upon 
different parts of the column, whence they might germinate 
in any direction, but, in spite of Darwin, who says the 
grains " readily adhere to any object," I have tried to 
remove thein at all stages of development and not one 
grain could I get away, not even with the hairy edge of a 
piece of blotting paper ; now I am thinking that the 
earliest tiilies as they elongate may drag out and carry 
down from the poUinia grains that may be later in 
germinating, and would thus add meshes to the net. How 
does my supposition stand ': I should add that pollen 
masses almost entirely disappear when the threads are 
most numerous. 

24, Iffley Road, C. E. Clark. 

Hammersmith, W., 

November 16th, 1903. 



Janvary, lOOL] 



KNOWLEDGE. 



in 



A FOG BOW. 

TO THE EDITORS OF KNOWLEDr.E. 

Sirs. — I slioiilil like to know if any of yo\ir roaders oau 
explain a strange phouonienou which I saw whilst 
travelling to Brighton from Hastings l)y train, about 
7 o'clock ou the evening of the 30th of September last. 
Tbe night was hazv. and looking through the oiieu window 
I distinctly saw outlined against the sky a circle, or rather 
sux oval-shaped bow enclosing a long cross ; tbe lower ]iart 
of the vision being veiled in mist, the tones were neutral 
and soft, though clearly defined. It disappeared from 
view suddenly, and though I watched for quite half-an- 
Lour, it did not appear again. The train at this time was 
running through the flat marshy country, known, I believe, 
as Pevensey Level, therefore skirting the sea-shore. A 
picture of a similar appearauce in Whymper's "Scrambles 
amongst the Aljjs," recalled the circumstance to me. 

Beckley. Mary Frasek. 



i3'b\t\xatv. 

HERBEKT SPENCER. 

It is with deep regret that we record the death of Mr. 
Herbert Spencer, which occurred in the early morning of 
the 8th of December, at his house in Brighton. 

The last survivor of the many eminent men of his time, 
Spencer enjoyed the unique distinction of completing the 
stupendous task he had set himself as the purpose of his 
life, a task which oceuiiied him for the kmg [)eriod of 
thirty-six years (1860-1896). It is doubtful whether the 
history of letters contains a more remarkable instance of 
the amazing results of courage and tenacity than is found 
in the production of Spencer's Synthetic Philosophy. 
•• How insane ray project must have looked to oulooker.s," 
he says, when with his small resources frittered away, and 
his health |)ermanently im[)aired by overtax of brain, he 
was obliged to desist by reason of nervous breakdown 
actually before the first chapter of the first volume was 
finished. But the philosopher afterwards pursued his 
course undeterred, and he completed it with the ex[)ression 
of the modest satisfaction that losses, discouragements, 
and shattered health had not prevented the fulfilment of 
his long task. 

Born in Derby on the "i/th Ajjiil, 1820, the son of a 
teacher of mathematics, he shared w'ith John Mill the 
distinction of having his education directed entirely at 
home, although in Spencer's case an uncle assisted the 
father. But he never had any experience of school or 
college, and he early abandoned his profession in order to 
devote himself entirely to speculative thought. Spencer's 
long career is singularly uneventful in personal history, 
and it is certainly by no desire of his that the world knew 
anything about him. But as a frequent contributor to 
the Westminster Review, in his earlier days, Spencer was 
brought into contact with many of its then brilliant 
writers, and his striking originality was displayed in 
association with Hamilton and the two Mills. From the 
year 1861), when the philosopher first resolve<l to concien- 
trate himself upon his great project, Spencer's own life is 
little more than the story of the publication of the 
successive parts of his system of Philosophy, until that 
happy day in 1896, when he reached the close of his long 
labour, and found pleasure in his emancipation. He had 
the felicity to receive a congratulatory address from his 
contemporaries eminent in science, literature, and 
philosophy, and arising out of thiit address, Mr. Hubert 
Herkomer painted the well-known portrait which is 



exhibited in the Tate Gallery, lu joining the signatories 
to this address, Mr. Gladstone most aptlv expressed the 
general feeling as to Spencer's unsellish labdurs ... "I 
beg that you will, if you think pro]ier, set me down as an 
approver of the request to Mr. Spencer, whose signal 
abilities iind, rarer still, whose manful and seU'-dciiyiug 
character are so justly objects of admiration,'' 



Bvitisl) (!5rnirt)olo{i;ical Notes. 

Conducted by Haury F. WiTiiEuiiT, f.z.s., m.h.o.u. 

Bird Migration in Solwaii, bi/ Roherl Sereice. J/.R.O.C. Cinnalx of 
Scott. Nat. Hist., 1903, pp 193-20 !■). -This is an interesting iin'il 
distinctly valuable article of actual obser\iition of birJ migration. Of 
the arrival of birds, sucli as I'^inclics and Warblers, Mr. Service 
writes: — " ... it requires the minutest attention to sec the indi- 
vidual birds arrive one by one. They seem to drop literally from t;he 
clouds Let one's attention be diverted for a moment, lu'xt time you 
look at a particular place there are oiu', or two, lU- tlireo birds that 
were not on the spot last time you i:lanced at it." Of tlie call notes 
heard during the progress of a great migratory movement at night, he 
writes: — "There is not one of us but will be confounded and 
humiliated to Ond that a very large jtroportion of the sounds cannot 
I)e assigned to any known species witli certainty. Of course, the 
e.vplanation lies in the fact that birds when on migration use notes 
tliat arc not required at other periods of their lives." Of the altitude 
at which birds migrate the writer stiit(-s : — " Skylarks and Swallows 
are about the only birds T ;im acquainted with that migrate at a com- 
paratively low level. (J\ute invarial)ly other birds that I have seen 
actually starting on tlu'ir long journey mount very quickly upwards in 
a slanting direction, till they reach a height .at which they can only be 
recognized by some peculiarity of llight. " There are many inte- 
resting observations in this paper. Mr. Service has not read, appa- 
rently, Mr. Ivigle Clarke's valuable papers on the subject, and the 
records of his own actual observations have been uninfluenced, 
seemingly, by those of others. 

Barred Warbler in Lincolnshire {Zooloffixt, 1903, p. .363). — In an 
accouut of the migration of birds in North-east Liucolushirc during 
the autumn of 190'i, Mr. (>. U. Caton Ifaigh re.;ords that he shot a 
young fem-ile of this Warbler .at Nortli Cotes on September 2uth. 
This is, I believe, the third specimen of the Barred Warbler which 
Mr. llaigh has recorded, and the eighteenth or so which has occurred 
in the British Islands. 

Sabine's Gull in Yorkshire {Zoologist, 19J3, pp. 3.")3, 301, 430). 
—The Rev. Julian G. Tuck has now recorded the occurrence of five 
(four adults) Sabine's GruUs in September and October last on the 
Yorkshire coast. This arctic species not infrequently visits our 
shores in autumn, but most of the previous records have referred to 
immature birds. 

Bare Birds in Kent and Sussex {Zoolor/ist, 1903, pp. -US- 12.5). — 
Mr. N. F. Ticehurst here tabulates the renv.irkable number of rare 
birds which it has fallen to the lot of ornitliologists in Sussex and 
Kent tj recori during the last twelve mmtlis. The most noteworthy 
of these have already been reported in these columns. 

All aintribntioas to the column, either in the v:aij of notes or 
phol(i(jraphs, should he forwarded to Harey F. Witiierhv, 
at the OJice of Knowledge, 326, High Holborn, London. 



i^otcs. 

Zoological. — According to recent information, the 
white rhinoceros (Rhinoceros simus), at one time believed 
to be all but extinct, appears to be comparatively common 
on tiie northern fmntier of the Congo Free Stale and the 
adjacent districts of the Sudan. 

The important anthropological and zoological collections 
brought home by Messrs. Robinson and Aunandalc from 
the Malay Peninsula are to be described in a new publici- 
tion, entitle 1 Fasciculi Maiayense>i. The first part, con- 
taining an account of Mammals, by Mr. J. L. Bonhote, 
has already been issued. Sixty-four is the approximate 
number of mammalian species included in the collection, 
of which eight are described as new. 



u 



KNOWLEDGE 



[Januaky, 190i. 



Great interest attaclies to the descriptiou b}- Dr. Mas 
Sclilosser, of Berlin, in the Ahliandhnigen, of the Eoyal 
Bavarian Aca<3emy, of a large collection of fossil teeth of 
mammals obtained from the druggists' stores of various 
jKirts of China, where they are sold as medicine. Many of 
these teeth— locally known as dragons' teeth— appear to 
be obtained from caverns, but others ]irobably come from 
the loess, or alluvium, while yet others are derived from 
older formations. Judging from the quantities in which 
they are sold in the bazaars, these teeth must exist in 
enornjous numbers in some parts of the Chinese Empire. 
The remains include those of deer, antelopes, three-toed 
horses {Hijjparion), rhinoceroses Chahcotherium, ances- 
tral forms of camel {PanicameJus), giraffes, okapi-like 
ruminants, pigs, hysenas, and sabre-toothed tigers One of 
the hy»nas {Hyxna gigantea) is by far the largest of its 
tribe," the upper earnassial tooth measm-ing tvro inches in 
length agamst one-and-a-half inches in the existing 
spotted species of Africa. Especial interest attaches to 
the ancestral camel, since North America is supposed to 
have been the original home of the Camelidas, and that 
continent was in close connection with north-eastern Asia 
in Tertiary times. Not less noteworthy is the occurrence 
of remains of antelopes of an African type, as well as of 
others alUed to the Indian nilgai. This seems to refute 
tlie theory that the antelopes of Africa originated in that 
continent (where the nilgai, which is a near relative of the 
kudu and bushbucks, is unknown), and to confirm Prof. 
Huxley's hypothesis that they are really immigrants from 
Asia. 

At the first meeting of the Zoological Society for the 
present session, Mr. O. Thomas described a gigantic rat 
from New Guinea, which he regarded as representing a 
new genus, and named Hyomijs meeki. 

A fortnight later, at the second meeting of the same 
liody, Mr. E, I. Pocock called attention to a remarkable 
habit of the Australian spiders of the genus Besis. These 
spiders live in the crevices of rocks between tide-marks on 
the shore, and by spinning a closely-woven sheet of silk 
over the entrance, imprison a mass of air in which they 
are able to live during flood-tide. 

Two interesting additions have been reeentlv made to 
the British vertebrate fauna. Till 1899, when it was 
detected on the coast of Brittany, the giant goby (Gohitis 
capito) was believed to be a jmrely Mediterranean fish. 
During the past summer, Mr. F. Pickard-Cambridge, by 
carefully searching the rock-pools, has discovered this fish 
on the Cornish coast. One of his specimens is figured in 
The Field. 

The second addition is an entirely new species of bank- 
vole (Evotomya skoinvreiisis), from Skomer Island, off the 
Pembrokeshire coast. According to its describor, Captain 
Barrett-Hamilton, this species differs from the common 
bank-vole (E.glareolus) not only in colour and size (being 
much larger), but also in the structure of the skull ; it 
belongs, in fact, to a distinct group of the genus. The 
description of this new species appears in the Proceedings 
of the Royal Irish Academy. 

The Americans are coutcmjilating a great undertaking ; 
nothing less than a complete biological survey of the 
Eastern Holarctic (or Palajatcticj region, that is to say, of 
the greater part of the extra-tropical area of the northern 
hemisphere. The proposed survey is to be undertaken on 
the lines of the one which is being brought to a conclusion 
in the United States, and it is calculated that it will take 
ten years to accomplish. The funds are to be supplied by 
the "Carnegie Institute. Such a survey, it is urged, would 



alone enable us to understand the true relationship of the 
fauna of Northern Asia and Europe to that of North 
America, and would likewise help to espilain the origin of 
both faunas. According to American ideas, the vast 
amount of material contained in the museums of Europe 
is of little or no use for such a purpose ; and it is in 
contemplation to collect the whole vertebrate fauna of this 
vast area section by section. If the project be carried 
tlu'ough, we may expect to be inundated with descriptions 
of so-called new species, comparable to the seventy which 
have just been named from the islands of Malaysia, by 
Mr. G. S. Miller, in a paper published in the " Mis- 
cellaneous Collections " of the Smithsonian Institution. 

Dr. W. G. Eidewood recently exhibited to the Linneau 
Society the frontal bones of a horse showing a pair of 
rudimentary horns, , very similar in position to those of 
some of the ruminants. In the opinion of the exhibitor, 
this feature can hardly be regarded as an instance of 
reversion, since none of the extinct ancestors of the horse, 
of which (as indicated in an article in our present issue) 
the .series is remarkably complete, show any traces of 
similar appendages. It is unfortunately not known 
whether the bony cores were covered in life with horn. 
This interesting specimen has been pi-esented by Mr. A. 
Broad, of Shepherd's Bush, to the British "(Natural 
History) Museum, where it is now exhibited. 



I^otfccs of Boons. 



'•British Mammals: An' Attempt to Describe and 
Illustrate the Mammalian Fauna or the British 
Islands fro.m the Comjiexcemext of the Pleistocene 
Period down to the Present Dav." By Sir Harry John- 
ston. (Hutchinson.) Illustrated. Price 12s. Od. — The author 
o£ this handsome addition to the ''Woburn Library" is 
apparently convinced that it is illogical to separate the animals 
of to-day from those of yesterday, and he accordingly includes 
in his account of the mammals of the British Islands not only 
those now to be met with there in a wild state, but likewise 
those that have been exterminated within the historic period, 
together with those extinct forerunners of the latest geological 
epoch. Whether this method is any more logical than the one 
which excludes extinct types may well be a matter of opinion, 
for if the animals of yesterday come witliin the sco])e of the 
work, there is no reason why those of the day before should be 
left out in the cold. Accepting, however, both his extension 
and his limitation of the subject, we think that Sir Harry 
Johnston has succeeded in producing a very readable and 
attractive book, and one which may, in its general scoi)e and 
style, well form a model which more scientific zoologists would 
do well to copy. An absence of details is noticeable, and the 
relations of the few surviving British mammals to their 
relatives in other lands and to their extinct predecessors are 
sketched in a manner which cannot fail to interest. Indeed, the 
work is much more than is indicated by its title, since it treats 
largely of mammals in general. 

While commending the general style of the work, we must 
at the same time warn our readers that h must by no means 
be accepted as an exhaustive account of Briti.sh mammals, or 
one that is free from errors. For instance, while in the case of 
one species of the mouse tribe the local sub-species are given, 
in some of the others they are omitted. This, of course, is 
inexcusable. It woukl'have been perfectly legitimate to ignore 
bub-species i» toto, but to notice them in one case and omit them 
in others, can only be taken to mean either that the author is 
inexcusaljly careless, or that he knows his subject imperfectly. 
We might also refer to certain inconsistencies in regard to 
nomenclature, did space permit. To justify the assertion that 
the book is by no means free from serious errors, we may cite 
the statement on p. 20'J to the effect that ancestral rhinoceroses 
had four toes on each foot, and also the one on p. o7u that 



Jasu.ujy, 1904.] 



KNOWLEDGE 



15 



^facaqiie monkevs are the only ropresentativos of their kind 
whioh in Asia inhabit districts with a climate ;is cold as that 
of England. The author's theories, too. must bo accepted with 
reserve — notably the suggestion (p. iiiil!) that American monkeys 
originated in Africa, seeing that not a vestige of the remains 
of one of these creatures has hitherto been discovered in that 
continent. 

A striking feature of the volume is formed bj' the coloured 
plates 'reproduced from the author's own sketches), which 
differ markedly in style from the illustrations commordy seen 
in zoological works. As to the merits of these sketches, we 
must, however, leave our artist friends to decide. 

'The Moon: CoNsmEUEn as a Planet, a World, and a 
Satellite." By James Nasniyth, c.e., and James Carpenter, 
F.R.A.s. J[urray.) — The moon is a dead and unch.-inging world. 
As it was when tialileo looked upon it through tlie first telescope, 
so it was when Nasmyth and Carjienter brought out the 
third edition of the " Moon " in 187.'), and so it is to-day, 
when the publishers have issued a verbatim reprint of the same 
book. Perhaps it is because of its unchangeableness that so 
little progress in our knowledge of the moon seems to have been 
attained in the last quarter of a century or more, for the joint 
authors raise the same problems, and give the .same doubtful 
answers to the same questions that we do to-day. The book is 
in fact up-to-date for all intents and purposes. In illustration 
alone do we seem to have made a notable selinograpliical 
.advance. When Xasmyth and Carpenter wrote, photograplij' 
was a very unskilful assistant to the study of the moon, and 
their lunar drawings were (as they still are to-day) incomparably 
the finest representations made by hand of the moon's surface. 
The re-publication of the book in a more convenient size, and at 
tlie greatly reduced price of 5s., will meet with wide acceptance. 
The paper and print are both pleasing. We notice one mis- 
print on p. 79, where ^^r, is written for juW- 

'•MiNTTE Marvels of Nattri:." By John .J. Ward. 
(London: Isbister & Co.) — The aim of the author of this book 
is to exhibit in a popular manner some of the striking and 
interesting subjects which are revealed by the microscope, and 
to describe them in such a way as will attract the unscientific 
reader. To this end the book is freely and admirably illustrated 
by 184 reproductions, principally photo-micrographs, and they 
cover a very large range of subjects. Bearing in mind the 
jmrpose of the book, the critical judgment is largely suspended. 
Errors there are, but not such as substantially weaken its 
object. A microscopist is apt to become a little impatient when 
he sees a group of specimens which includes Anchors and plates 
from the skin of the Synapta included in the title of '" Diatoms.'' 
.Several other little blemishes occur, and the description of the 
manner of the use of the pulvUli of the fly's foot — for so long a 
subject of controversy — might with advantage be revised. .Still 
the book, placed in the hands of one who is unacquainted with 
microscopical subjects, is likely to create interest and lead to a 
desire for further information and investigation ; if it succeed 
in this, its purpose will be achieved. 

" BciiDisT India." By Prof. T. W. Rhys Davids. Pp. xv. 
+ 'i?>2. (Fisher Un win.) Illustrated. l>s. — The rise of Buddism 
in India has provided Prof. Rhys Davids with a theme for a 
scholarly work. If India were subject to a nation like Germany, 
exploration of the rich field of historical research, of which this 
book gives us an inspiring sketch, would be made a subject of 
national concern ; but here it is not considered necessary to 
make inquiries into the ethnology or archajology of the races 
which constitute our Empire, and it is left to scholars like Prof. 
Davids to rescue such knowledge from oblivion. It is usual to 
adopt the Brahmin idea of ancient India, with its doubtful 
theories of castes and history, but inscriptions and other records 
have provided material for the conatiuction of a connected 
account of India without accepting the Brahmin point of view 
as the final one, and equally true five centuries before Christ 
and five centuries after. Prof. Davids describes from the avail- 
able evidence the kings, clans and nations, social and economic 
conditions in India in the sixth and seventh centuries i;.('. 'I'ht^ 
Buddist influence was most early felt in tlie north of Indi;i, 
and the picture of village life at that time shows that the 
" ma.ss of the people, the villagers, occupied a social grade 
quite different from, and far above, our village folk." The 



claim of the priests to social superiority was not recognized 
and the caste system as it is now understood was unknown. 
There were different families or clans, but the caste system, in 
the exact use of the torni, did not come into existence until 
long afterward. As to literat\n'o, the oldest reforei\c'c to writing 
is in a tract dating approximately to 4.')0 li.c. The priests 
appear to have been indill'erent and even opposed to the use of 
writing. " All the present available evidence," remarks Prof. 
Davids, "tends to show that tlie Indian alphabet is not Aryan 
at all ; that it was introduceil into India by Dravidian merchants ; 
and that it was not, in spite of their invaluable services in other 
respects to Indian literature, to the priests, whose self-interests 
were opjioscd to such ili.scoveiics, but to trader.s, and to loss 
prejudiced literary circles, that India owes the invention of those 
imjirovements in the mechanical aids to writing that enabled tlie 
long previously existent knowledge of letters to bo applied at 
last to the production and preservation of books." 
liimitations of space prevent us from mentioning more 
of the interesting points with which this volume is 
filled. I'luddism slowly but continually lost its place 
as a national faith and now there is .scarcely a Buddist 
left in the land where Buddism arose, (j'hanges in the faith 
itself, changes in the intellectual standard of the people, and 
the influence of foreign tribes which invaded India from 
the north-west, are suggested as causes for the decline and fall 
of Buddism in India. Prof. David's story of the rise of the faith, 
and the conditions of the people who professed it in India, is a 
contribution worthy of his great learning, and of great interest 
to every student of history. 

" OnSEKVATioNS OF A Natura[.isi' r^^ tiik Pacikio hktwhkm 
18'Ji; AND i.H'J[)." By H. B. Gnppy, M.r.., f.r.s.e. Volume I. 
" VanuaLevu, Fiji." 'Pp. xx., .".'.Vi. (Macmillan.) l.5s.— This book 
is the work of one who does not shriidc from detail; and it has 
more in common with the elaborate memoir of a State survey than 
with the ordinary record of a traveller. In a country where the 
annual rainfall varies from. 1(K) to 2.'i0 inches, whore the interior 
tends to become wilder and less populous, and where dense 
forest prevents the mapping of geological boundaries, Mr. 
Ouppy has made elaborate notes of every rock-exposure that ho 
could visit. He includes the tine volcanic necks that rise sheer 
above the agglomerate layers and the marine sediments of the 
plateaux ; and he shows how the general volcanic action took 
jjlace in Cainozoic times beneath the sea. Inclining, evidently, 
to a theory of U[ihcaval, rather than to the difficult hypothe'sis 
of a recession of the level of the sea, he yet does not absolutely 
commit himself on this important subject. His unwillingness 
to generalise makes the book rather serious for the reader. 
The types of lava met with are classified with what seems an 
excess of detail, .secdng that nothing new is revealed concerning 
their behaviour or occurrence as rock-masses. The felspar 
crystals are carefully measured under the microscope, and the 
presence or absence of fluidal structure in the ground-mass is 
noted in each case. In dealing with the felspars which are 
commonly called " laths " by workers with the microscope, Mr. 
Ouppy prefers the fourteenth century term " lathes." His 
phrase " lamellar extinction," moreover, does not strike us .as a 
very happy one. Still less do we like the '' formulio " devised 
for the comparison of one rock with another. This is all very 
well for the note-book of one who is correlating a large series, 
but such a system seems hardly necessary in the published work 
This cumulative evidence as to the interstratification of marine 
sediments and volcanic ilfbr/s throughout Vanua Levu is of 
wide interest and imiiortance; tho minimum emergence (p. 31.5) 
that has made the present island is valued at 2500 feet. The 
history is one of a struggle between the forces of elevation and 
the constant planing action of the sea. A rise of another tJDO 
feet would connect 'V'anua Levu with its sister island, Viti Levu, 
on the south-west. The plateau that forms a floor for the later 
accumulations is regarded as due to spreading lava flows (p. 371-5). 
Similar plateaux, cora|)leted in Oligocene tunes, and now buried 
in marine sediments, would doubtless be revealed by local 
elevation in the region between Ireland and the FariJo Isles. 
The whole book is admirably produced, but wo cannot help 
thinking that it would have gained by considerable excisions, 
and by the substitution of a classified list of the localities from 
which specimens hail been collected, in place of the detailed 
descriptions of so many individual instances. 



16 



KNOWLEDGE. 



[January, 1904. 



"Among the Night People." By Clara D. Pierson. 
Pp. xii. + 221. (John Murray.) .5s. — Tt may be doubted 
whether any useful scientific purjiose is served by regarding the 
lower animals as reasoning creatures possessed of sentiments 
like those of human beings and a vocabulary superior to that of 
many people. In the dainty book before us not only do 
raccoons, rats, foxes, weasels and other " varmin " carry on 
animated conversations, but also mosquitoes, caterpillars, fire- 
flies and molhs. Children have no difficulty in imagining a doll 
or rocking horse to be endowed with life, so that the stories in 
this book will appeal to them vividly. Regarded as food for 
imagination, comparable with fairy tales and classical legends, 
the stories are very good and will please many young people. 
As for natural history, well, there is a vein of it among the 
whimsicalities described and the fine feelings pourtrayed, but 
the pity of it is that children will be unable to discriminate 
between what is real and what imaginary. 

"Mathematical CEYSTALLOGRAPiiy and the Theory of 
Grouts of Movements." By Harold Hilton, m.a. Pp. xii. 
-f- 'I6'2. (Clarendon Press.) 14s. net. — Earnest students of 
crystallography will be grateful to Mr. Hilton for his treatment 
of a branch of the subject usually neglected in English text- 
books. The geometrical theory of crystal structure is a 
fascinaling field of study which the mathematician and the 
crystallographer can explore to the mutual advantage of both. 
From considerations of symmetry and finite groups it is shown 
that there are onl}- thirt}'-two groups of movements consistent 
with the law of rational indices, and therefore applicable to 
crystallograph}'. The argument thus develops the thirty-two 
crystal classes given in text-books on the subject. Three 
chapters are devoted to the description of the more important 
properties observed in crystals, and with chapters, among others, 
on the points already mentioned, form the first part of the book. 
The second part is devoted to theories suggested to account for 
these properties, the methods and notation used by Schcinflies 
in his "Krystallsysteme und Krystallstructur'' being closely 
followed. The work of other investigators of the geometrical 
theory of crystal structure, which may now be regarded as 
fairly complete, is included, so that the volume is of importance 
both for reference and as a supplement to modern text-books. 



BOOKS RECEIVED 

Direction of Bair in Animals and Men. By Walter Kidd, M D., 
r.z.s. (A. & C. Black.) lUustratoa. 5s.net." 

The Cosmos and the Creeds. By Capt. AT. U=borne Moore. 
(Watts) 4s.net. 

The Sir/ns of Life. By Augustus D. Waller, M.D , F.R s. (Murrav.) 
Illustrated. 7s. Bd. net. 

Essai/s and Addns.^es, 1900—li)0:i. By the Et. Hon. Loid 
Avcbury, P.c. (Macmillan.) Ts. €d. net. 

JEton Nature Sliid;/ and Observational Lessons. By Mattliew 
Davenport Hill, M.A., r.z.s, and Wilfred Mark Webb, P L.s. 
(Duckworth & Co.) Illustrated, .'is. Gd. net. 

/School Oeometri/. Part V. By H. S. Hall, Ji.A., and F. H 
Stevens, m.a. (Macmillan.) Is. fd. 

Infection and Immnniti/. By Geo. M. Sternberg, m.d, il.ii. 
(Murray.) 6s. net. 

St Anselm. Froslogivm ; Monologium ; An Ajpendix in lehalf 
of the Fool hy Gaunilon ; and Cur Leiis Homo. Translated by 
Sidney Norton Deane, e.a. (Kegan Paul.) os. cloth. 

Evolution and Adaptation. By Thom.as Hunt Morgan, TH. u. 
(Macmillan.) 12s. 6d. net. 

Nem Theory of Oryanu- Umlution. By James AV. Barclay. 
(Blackwood.) 39. Gd. net. 

Some Indian Friends and Aquaintances. By Lt.-Col. D. D. 
Cunningliam, CLE , F.R S. (Murriiy ) 129.net. 

The Canon of Reason and Virtue. Ti'anslated by Dr. Paul Carns. 
(Kegan Paid.) ]s. 6d. 

Guide to the Civil Service. By John Gibson, 5la. (Hodder & 
Stoughton.) 3s. Gd. 

Fducaiion .- Intellectual, Moral, and Physical. By Herbert 
Spencer. (Kationalist Pftss Association ) 6d'. 

Journalism as a Profession. Bv Arthur I.awroiice. (Hodder & 
Stoughton.) 38. Gd. 

Publications of the Lid- Olserratory. Vol. A'l. 1G03. Meridian 
Circle ObseiTations. 

Annual llej^ort of the Smithsonian Institution, 1902. 



On the Absorption and Emission of Air and its Ingredients for 
Light of Wave-Lengths. By A'ietor Schumann. (Smithsonian 
Institution.) 

Annals of the Astronomical Observatory of Harvard College. 
Vols. XLVI., Part I., ami XLVIII., Parts V . VI., VII., VIII. 

Photov/raphy. Cbristmis Niiiuber. (Iliffe & Sons.) Is net. 

Who''s Who, 1904. 7s. Gd. net. 

Who's Who Tear Soik, 1901. Is. net. 

Whitaker's Alminacle, 1904. 2s. 6d net. 

Whitalcer's Peerage, 1904. 3s. 6d. net. 

Annual Report of the Smithsonian Institution, 1901 (U.?. Xational 
Museum.) 

Transactions of the Hull Scientifie and Field Naturalists' Club, 
1903. (Hull : Brown & Sons.) 3s. 6d. net. 

Bulletin du Jardin Botanique de L'lltat a Bruxelles. September, 
1903. 

Aijriculture, Live Stock, and Dairying in Argentina. By Robert 
Wallace. (Edinburgh ; Oliver & Boyd.) 9d. 

Williams and Norgate's International Book Circular 137. 6d. 

The Burlington Magazine. December. 2s. 6d. net. 

Eoss Limited Abridge Catalogue, 1903. 

Newton cf' Co. Supplementary List of Lantern Slides, 1903-4. 



THE ANCESTRY OF THE HORSE. 

By E. Ly'dekkee. 

If an e.xpert mechanical engineer, totally unacquainted 
with zoolo!:>-y and comparative anatomy, were shown for 
the first time the skeleton of a tapir, and told that it 
bekmged to an animal adapted to life in swamps, and were 
then asked if he could suggest improvements in the struc- 
ture of the bony framework in order that the animal might 
be suited for a life on the open plains, and possess a high 
turn of speed, there wouH be little doubt as to the nature 
of his answer. After examining the short limbs, with two 
]3arallel bones in the second segment, and their three or 
four tees each, he would at once say that it is essential to 
lengthen all the bones of these j)ortions of the skeleton, 
and to reduce the width of the foot either l)y diminishing 
the size of all the toes except the large middle one (which 
would have to be proportionately increased), or by doing 
away with them altogether. He might fiu-ther suggest 
that it would be imjjortaut to lengthen the bones of the 
lower segments of the limbs (except, of course, the three 
terminal ones) to a much greater extent than tlie upper 
one. And if he were specially inventive he might also point 
out that a much greater stride and far more mechanical 
power would be gained, if the animal could be made to 
stand only on the extreme tips of its toes, so that the 
whole of the hinder portion of the foot would be raised 
above the ground. Puitlier. he might also advise that it 
would confer strength and solidarity on the limbs if the 
two bones in the second segment of each were welded 
together, so as to form but one. 

If. moreover, he were told tliat the tapir is probably a 
short-lived animal, which feeds on soft marsh vegetation, 
and tliat it was essential to olitain an animal whose span 
of life should be from fifteen to twenty years, and whose 
food should consist of dry grasses and grain, he would 
naturally look at the molar teeth of the tapir. Tliese he 
Would find to have low crowns surmounted merely by a 
few simple ridges ; and if the skeleton belonged to an old 
individual, he would not be long in discovering that some 
or all of them were worn nearly or quite down to the roots. 
Obviously his answer would be that the crowns of the 
teeth must be very considerably lengthened ; and, more- 
over, so constructed as to be more capable of resisting wear, 
and better adapted for grinding hard substances than are 
those of the tapir. 

After this inspection of the skeleton of the tapir, we 



Januarv, 1904.] 



KNOWLEDGE. 



17 



must iinajjiue our ent;ineer to be iutroduced to that of the 
horse. " Here we have," he would say, " the very 
ideal aniiuiil you want, aud I can sugjjest absolutely no 
uieehanioal improvement iu its framework, save that I 
fail to re;dise the use of the two small splints of bone 
attached to the sides of the upper part of the eanuon-bone 
in eaeh limb."' 

Here, indeed, we have in a nutshell the essential differ- 
ence between the horse (and its near relatives the zebras 
and asses) and its earlv ancestors, which. althoui;h of 




FiS. 1. — Skeleton of Hyracotherium, of the Lower Eocene Period in 
North America and Europe. (After Cope.) 

smaller size, were generalized creatures not far removed 
in their organization from the tapir. In the ancestral 
tvpe there is abundant room for modification and speciali- 
zation, whereas in the other the possibilities of improve- 
ment and advance appear to have Ijeen exhausted, aud the 
animal is (with the aforesaid exception) practically perfect 
for its own special mode of life, and is the supreme 
development of which its line is capable. The mode in 
which this perfection has been attained during the slow 
couree of evolution, it is my jiurpose, so far as sjsace 
permits, to demonstrate in the present article. 

The earliest mammal to which we can at present defi- 
nitely afiiliate the horse and its relatives is one from the 
lowest part of the lowest, or Eocene, division of the Tertiary 
period known as Phenacodus. This was a short-legged 
creature not larger than a fox, with a relatively small 
head, long tad, and five toes to each foot. On these five- 
toed feet the creature probably walked much in the same 
way as the modern tapir, that is to say that although the 
wrist and ankle joints were raised well above the ground, 
all the three bones of each toe were applied to the same, 
and the sole was provided with cushion-like pads. Very 
important is the circumstance tliat in each foot the middle 
toe was symmetrical in itself, and decidedly larger than 
those on either side. The toes — and more especially those in 
the fore-foot — were distinctly expanded at the extremity, 
and during life were encased in horny sheaths which were 
probably more like hoofs than claws. Not less important 
is it to notice that in the skull the socket of the eye was 
not closed behind by a bar of bone, and was thus con- 
tinuous with the great hollow on the sides of the temples 
for the reception of the muscles which worked the jaw. 
As regards the teeth, it must suffice to say, firstly, that 
they were forty-four in number, as iu so many c)f the early 
generalized mammals, and that although well-marked 
tusks, or canines, were present in both jaws, there was no 
distinct gap at the commencement of the grinding, or 
cheek-series. Secondly, these cheek-teeth had very short 
crowns, surmounted by four simple conical elevations, or 
cusps, between which were a couple of smaller cusps. 
Into other details of the structure of this primitive 
creature it would be out of place to enter here. As to its 



coloration in life, no one has, I believe, hitherto ventured 
to make even a suggestion. 

When, how<'ver, we advance one step further iu the 
scale, and come to the Hiirdrotlifriuiu of the Lon<lon Clay 
division of the Koceno, American paheontologists have 
been bold enough to say that the creaturi! had a. trans- 
verL^ely striped coat comparalile to that of the modern 
zebras ; the reason for this 1 icing that all members of the 
horse trilie display, especially in the case of hybrids, a 
tendency to throw back, or revert, to a strijx^d typ' of 
coloration. Whether we are justified in Mieving this 
ancestral striping to date so far back as the Hyracotherium, 
it is not for me to say. 

As regards its organization, Hi/racotheriuni differed 
markedly in many respects from the earlier Phenacodnn, 
this Ix'ing most clearly displayed in the skeleton of the feet 
(Fit;. "2). Tilt' fore-foot had, for instance, become unsyni- 
metrical, owing to the l(»ss of the first, or "great," toe; 
the outermost of the four remaining digits lieing quite 
small, and having no fellow ; the foot being thus com- 
parable to the fore-foot of a tapir. The hind-foot, on the 
contrary, although more reduced, still retained the 
symmetrical form of the ancestral type, having lost both 
the first and the third digit, aud thus being three-toed, 
like the corresjionding foot of a tapir. Hi/rai-ollieriiim, 
which was no larger than a fox, still resembled its ancestor 
in having two bones to the second segment of each limb, 
that is to say a nidlus and ulna in the fore, and a tibia and 
fibula in the hind limb. Here it should be mentioned that 
between Hijracotherhim and Phenacodnt! there may have 
existed an intermediate type with four toes to each foot. 
As regards its cheek-teeth, the creature presented a distinct 




Fig. 2 — Bones of Left Hind and Fore Feet of Syracotherium. 

advance on Phenacodue. In the latter, as already said, 
the crowns of these teeth were surmounted by simple 
tubercles. On the other hand, in the former, three of these 
cusps in the upper teeth tend to unite to form an oblique 
anterior transverse ridge, while the thi-ee hinder ones tend 
to make a second posterior ridge; at the same time the 
two outer tubercles show indications of uniting so as to 
form a continuous outer wall to this part of the crown of 



IS 



KNOWLEDGE 



[Jakcaby, 1904. 



the tooth ; this pattern being a forerunuer of that obtain- 
ing in the L-heek-t«eth of the horse. The long tail of 
Hyracotheriiim Ts-as probably whip-like. Eemains of the 
genus in question occur in the Lower Tertiary of North 
America as well as in that of Europe. In somewhat later 
deposits in both continents occur remains of more or less 
closely allied mammals known as Packynohphus, which 
mav or may not be in the direct horse ancestry. Later 
still, the weU-known Palaeotheria of the Oligocene strata 
of France and England, some of the species of which 




Fig. 3. — Crown Surfaces of a Bight Upper Cheektooth of Squiis 
and of Two Eight T. pper Cheek-teeth of Anchitherium. 

were considerably larger than a tapir, were certainly off 
the main line of descent, their structure approximating 
more to that of the tapir type. When, however, we reach 
the Miocene Tertiary of both hemispheres we come upon 
remains of mammals which, although closely resembling 
the palseotheria in dental structure, yet exhibit unmistakable 
signs of nearer affinity with the horse. In Eumpe these 
creatures are known as Anchitherium, but some of the 
American forms are separated genericaUy as Miohippus, 
one of the points of distinction being that whereas the 
front, or incisor, teeth of the latter are of a perfectlv 
simple structure, those of the former begin to exhibit a 
slight infolding of the summit of the crown, thus fore- 
shadowing the deep pit, or " mark," chai-acterisiag those of 
the horse. The cheek-teeth oi Anchitherium (¥\g.'i),th<m^\i 
still low-crowned, have acquired fully- developed transverse 
crests, and a continuous outer waU. Numerically the teeth 
agree with those of Syracotherium and Phenacodus, but a 
difference is to be found in the relatively small size of the 
first pair of cheek-t€eth iu each jaw. A marked advance 
on the former is displayed in the fore-foot, which bv the 
loss of the outer digit has once more become symmetrical, 
with only three toes. In both limbs the cannon-bone 
and toe- bones of the central digit have become greatly 
enlarged at the expense of the lateral digits, which are 
proportionately diminished, and there is a marked increase 
in the relative lengths of all the bones of the lower portion 
of the limbs. Moreover, it is noticeable that although the 
radius and ulna in the second segment of the fore-limb, 
and the tibia and fibula in that of the hind one remain 
distinct from one another, yet the ulna and fibula have 
become relatively more slender than in the earlier forms, 
and are in places more or less welded respectively to the 
radius and the tibia. In the matter of bodily size an 
important advance has also been established, one of the 
European species of Anchithe/nnm being approximately of 
the dimensions of a tapir. In one of the American species 
of the closely allied genus Mesohippug a remnant of the 
upper end of the metacarpal, or uppermost bone, of the 
outermost, or fifth, toe still persists. 

The next advance in this wonderful evolutionary chain 
is presented by the members of the genus Protohippus, of the 
Upper Miocene formation. These animals were essentiallv 



horses, although retaining the three toes of the ancestral 
Anchitherium. The skull, for instance, had become 
relatlvelv large and elongated, with the socket of the eye 
separated from the temporal pit behind by a bony bar, and 
thus enclosed by a complete ring of bone. The front, or 
incisor teeth, were separated by an interval from the tusks, 
or canines, wliich were relatively short, and divided by 
another gap from the teeth of the cheek-series. Moreover, 
the summits of the incisors were pushed in, like the ia- 
turned fingers of a glove, thus giving rise to a distinct 
"mark'' when half-worn. As regards the cheek-teeth, 
those of the first, or " nulk " series, were curiously like the 
permanent set in the Anchitherium. The second, or 
persistent series, on the other hand, had acquired tall and,, 
squared c'rowns, which only developed roots when the 
animal was fully adult. In the pattern on the crown 
these teeth closely resembled those of the modern horse, 
with the exception of certain details which need not be 
noticed here ; such pattern being the result of an excessive 
elevation of the simple crests of the Anchitherivm molar, 
coupled with the pushing-in of certain portions, and the 
fiUing-up of the resulting hollows by the substance known 
as " cement," which is altogether lacking in the former. 
Then again, the first cheek-tooth in each jaw had become 
small and rudimentary. In the feet the lateral toes, 
although complete, had become relatively small, and 
scarcely, if at all, reached the ground, being in fact 
analogous to the rudimentary lateral toes of the ruminants. 
On the other hand, the central toe in each foot, with its 
supporting cannon-bone, was proportionately enlarged, 
and had become the real support of the body ; the animal, 
like the modern horse, apparently standing solely on the 




Fig. 4. — Skeleton of Left Hind and Fore Feet of Protohippus. 

tenninal joint of its middle toes. Higher up, the ulna in 
the fore-liml), and the fibula in the hind one, had become 
imperfect. 

In the ordinary Pliocene three-toed horse, or Hipparion, 
of Europe and Asia, together with its North American 
representative, separated by some naturalists under the 
name of Neohipparion, the lateral toes were quite function- 
less, the ulna in the fore-limb had become fused with the 
radius, and the fibula in the hind-limb with the tibia, 
while the cheek-teeth had acquired somewhat taller and 



Januaby, 1904.] 



KNOWLEDGE. 



19 



more oouiplicateii crowns, aud tbe s^ps on each side of 
the oanines were larsjer. Moreover, the small first cheek- 
tooth, or premolar, es{<>oially in the lower jaw, was ijiiite 
riulimeutarv, and often shed in old a>;;e. There is, like- 
wise, another point in connection with the cheek-teeth of 
this aud the last Ljenus. lu Aiichitlifriitin imd the earlier 
forms, the <'heek-teetli. with their ridt^ed crown- surface, 
were adapted solelv for an uii-and-down champing,' move- 
ment, such as occurs in the jaws of the pifjs. On the 
other hand, the Hat millstone-like surface formed l)v the 
cheek-teeth of the hippariou and the modern horse permits 
of a horizontal grinding movement, much better adapted 
to the comminution of hard substances. These three-toed 
horses were further peculiar for the presence of a depression 
on the sides of the face for a gland comparable to the 
tear-gland of deer and many antelopes ; traces of the 
depression being visible in certain modern horse-skulls, 
aud also existing in a much more marked degree iu the 
extinct Siwalik horse (Eqiivf! sivalfusis) of India. 

The presence of these face-glands indicates that the 
hipparious prolxibly frequented country covered with tall 
grass or bush, in which the scent given out liy their 
secretion would aid the members of a troop in tracing the 
whereabouts of their fellows. On the other hand, in the 
open grassy plains (which by the way are probably a 
comparatively recent feature in the history of the earth) 
such aids are quite unnecessary, and the glands have 
accordingly been lost in the modern horse and its relatives. 
In height the hipparion stood about 4 feet 6 inches 
(13'i hands) at the shoulder. In coloration it was 
probably strij^ed after the fashion of the zebras. 

During the Pliocene period horses obtained for the first 
time an entry from the North into South America, where 
they developed into two generic types known as 
Hippidiiim and Onohlppidiiim. Having large face- 
glands, and comparatively short and simple cheek-teeth, 
these South American horses were specially distinguished 
by the great length of the slit on each side of the face 
below the nose-bones. Evidently, therefore, they were off 
the line of the modern horse, although it is believed that 
the second, at any rate, were single-toed. If, as some 
believe, indigenous horses existed iu South America at the 
time of its discovery, they must have been Onohippidiums. 
In the Lower Pliocene of India aud the Upper Pliocene 
of Europe aud Asia appear for the first time true horses 
of the genus Equus, characterized Ijy the total disappear- 
ance of external lateral digits, the sole relics of which are 
the splint-bones at the upper ends of the cannon-bones, 
alluded to above as being the only superfluous aud appa- 
rently useless structures noticeable in the skeleton of the 
horse. They seem, in fact, to be structures of which these 
animals have been unable to rid themselves ; and are 
actually injurious, being tbe cause of the disease known 
as splint. To the evolutionist they are, however, inde- 
scribably valuable, as affording incontrovertible evidence 
of the descent of the horse from the three-toed forms. In 
all the one-toed horses the pattern on the crowns of the upper 
cheek-teeth (Fig. 8) differs in a certain detail from that of 
the hipparions. The Pliocene horses approximate, however, 
in this respect more to the latter than in the case with 
their modern descendants, as they also do in the somewhat 
shorter crowns of the cheek-teeth. Moreover, the occur- 
rence of a first upper piremolar (the " wolf-tooth " of the 
vets.) was less uncommon in these Pliocene species than 
in the horses of to-day ; and they occasionally developeii 
the corresponding lower tooth, which is quite unknown in 
the latter. Whether, however, the mares of the Pliocene 
horses resembled those of the present day in the absence 
of the canines, 1 am unable to say. 

Passing on from certainty to conjecture, it is probable 



that at least some of these Pliocene horses were striped 
like the zebras. S]iecies, however, such as the immediate 
ancestors of the modern /?'/»».< rnhdllus — the domesticated 
horse of the jiresent day and its wild or semi-wild relatives 
th(( dun-coloured ])onies of Mongolia — th(> wild asses, and, 
in a less degree, the extinct South African quagga, which 
took to a life iu the open plains in countries where there 
is strong sunlight, found this type of coloration uusuited 
to their needs and accordingly assumed a more or less 
uniformly coloured coat, as being best adapted for 
protective rescmldance in such situations. The above- 
mentioned tendency to revert to stripes, es|H'cially iu tlit^ 
case of hybrids, affords, however, proof ()f their zebra-like 
ancestry. 

As early as the Prehistoric ]jeriod, as we infer from the 
rude drawings of the animal by its first masters, the 
European horse was uniformly colourcKl — probably dun 
with dark mane, tail, and legs. It was a small heavy- 
headed brute, with n)ugh scrubby mane and tail, and no 
trace in the skull of the depressiim tor the face-gland. From 
this stock are descended the cart-horses and the ordinary 
breeds of Western Europe. The blood-horse, or thorough- 
bred, on the other hand, is a later imi)i)rtation into 
Europe either from Arabia, by way of Greece and Italy, 
or, as some think, from North Africa, the homo of the 
barb. It has been supposed that these Eastern horses are 
the descendants of an earlier domestication of the same 
stock. I have, however, recently shown the existence in 
an Indian domesticate.l horse-skull, as well as iu the skull 
of the race-horse " Ben d'Or," of a distinct trace of 
the depression for a face-gland, and the suggestion 
consequently presents itself that the Eastern horses 
(inclusive of thoroughbreds) are derived fnim E<iuus 
sivalensis, in which the face-gland may still have 
been functional. The thoroughbred, as contrasted 
with the cart-horse, exhibits the extreme limit of 
specialisation of which the equine stock is capable ; 
this being displayed not only by the gracefulness and 
beauty of its bodily form and the relatively small 
size of its head and ears, but likewise by the greater 
relative length of the bones of the lower segments of the 
limbs as compared with the upper ones, namely, the 
humerus in the fore-limb, and the femur in the hind pair. 
In this respect, therefore, the blood-horse departs the 
furthest of all the tribe from its tapir-like ancestors, as 
it does in its height at the shoulder. 

But it is not only in its skeleton that the horse exhibits 
traces of its affinity with its predecessors. On the hinder 
part of the foot a little above the hoof is a structure known 
to veterinarians as the " ergot." This, which apparently 
attains its greatest development in Grcvy's zebra of 
Somaliland, corresponds with one of the foot-pads of the 
tapir, anil points to a time when the ancestral horses 
applied the under surface of the fetlock to the ground. 
More remarkable still are the callosities, "chestnuts," or 
" castxirs," found on the inner sides of Iwth limbs in the 
horse (inclusive of the Mongolian wild ponies), but only on 
the fore-legs of the other species, which are likewise rudi- 
mentary, or vestigial structures. Although it has been 
suggested that these also represent foot-pads (with which 
they by no means agree in position), it is far more 
probable that they are really remnants of glands (similar 
to those found in somewhat the same situation in the 
hind-limbs of many deer and the front ones of many 
antelopes), and that their disappearance as functional 
organs was approximately coincident with that of the loss 
of the face-glands of the hijiparions, owing to both being 
no longer required. Even now, it is said, these callosities, 
when freshly cut, exude a humoui- the smell of which will 
cause a horse to follow for almost any distance. 



20 



KNOWLEDGE. 



[January, 1901. 




Conducted by F. Shilltngton Scales, f.e.m.s. 

MICROSCOPICAL RESOLUTION. 

For the meeting of the Royal Microscopical Society on the 
19th November, a paper had been announced by Prof. Everett, 
F.R.S., dealing with " Microscopical Resolution." Those 
interested in the theory of the microscope who attended in the 
hope of increasing their knowledge of this aspect of the 
subject were doomed to be disappointed as far as this paper was 
concerned, for the learned author had evidently misapprehended 
the scope of Equation .32 of Lord Rayleigh's paper on " The 
Theory of Optical Images," recently reprinted in the R.M.S. 
Journal. The elementary formula which Prof. Everett deduced 
in the usual elementary way for the difference of phase between 
adjoining slits of a grating — and which Lord Rayleigh gives as 
No. 45 — is quite correct, and leads, when discussed in a similarly 
elementary manner, to the familiar diffraction spectra, but 
without disclosing the not entirely unimportant intermediate 
secondary maxima. But Lord Rayleigh's paper goes far beyond 
this ; it determines the distrihution of light in the final image of 
a grating, with only these two simplifying assumptions : that 
the number of lines is infinite, and that the lines are negligibly 
narrow compared to the dark intervals. 

The theorists were, however, fortunate in hearing an ex- 
position from Dr. Johnstone Stoney, F.R.s. — a rare visitor— who 
was asked to speak. 

Having pointed out that the familiar but elusive " rays " of 
light can be used only for elementary purposes, and must be 
supplanted by " waves " in all thorough investigations, and 
having alluded to his method of resolving undulations into 
plane wavelets. Dr. Stoney proceeded to communicate some 
extremely interesting results of his experiments with 
gratings. 

He first showed how tuxi lines a certain distance apart could 
be resolved by an aperture quite incapable of resolving a greater 
number of Imes at similar distances. But whilst the lines 
are properly resolved— that is, separated by a dark interval— 
their distance apart is, in these circumstances, misrepresented. 
They appear too far apart in inverse proportion to the distance 
apart of the portions of two diffused diffraction fringes utUized. 
This is an experimental proof of the correctness of the 
reasoning leading to the Abbe theory, which is as novel as it is 
important. 

His next point was equally interesting and valuable. When 
the number of lines in a grating is finite, and particularly when 
it is small, the complete diffraction spectrum produced by the 
grating is not hmited to the familiar principal maxima ; there 
are (n-2)— n being the number of lines in the grating — secondary 
maxima between every two principal ones, and those of these 
secondary maxima which are near a principal maximum are of 
appreciable brightness. Dr. Stoney has been able to demonstrate 
that these secondary maxima, when combined with the direct 
light, (Ac first difractii/n-spectrum itself being excluded hy 
reducing the aperture of the nucroscope, are capable of giving a 
feeble kind of resolution. And, as in the previous case, there 
is again complete agreement between the results of the direct 
experiment and that to be expected theoretically, for the faint 
image secured in this way shows the exact defects and 
peculiarities which theory demands. 

Dr. Stoney's third point also proved of interest. Perhaps the 
greatest defect of the published accounts of the Abbe theory 
lies in the utter want of definite information of a practical kind. 
It is stated that there can be no complete similarity between 
object and image unless every diffraction spectrum of appreciable 



intensity is utilised, and api)arently with a view to impressing 
the confiding microscopist with the importance of this doctrine, 
certain experiments with the " Diffractions-platte " are mentioned 
which yield a dissimilarity between object and image that is 
absolutely startling. Of course, this is right when complete 
similarity is taken in its strictest sense, i.e., down to the minutest 
detail, which, however, no practical man would expect to see 
under any conditions. What the latter desires to know is how 
)inirh dissimilarity he must be prepared for, and to the ])ractical 
man Dr. Stoney's testimony as to the remarkable improvement 
of microscopical images when the second spectrum is admitted 
must, therefore, be a welcome guide. 

Dr. Stoney proceeded to make some further remarks on the 
importance of Condenser-adjustment in attempting very delicate 
resolving tests, but his interesting communication had to be 
terminated with a view to securing the remaining portion of the 
evening for another paper on the agenda. 

Very few microsco])ists are really competent to appreciate the 
value of microscopical theory, and the high importance of taking 
every advantage that can be suggested for accurate manipulation. 
It is to be hoped, therefore, that Dr. Stoney's suggestions may, 
in due course, appear in print, and thus afford an opportunity 
to intelligent and thoughtful workers to assess them at their 
proper value. Dr. Stoney's remarks were not only of interest 
but to the point, for microscopical resolution was the subject 
which was opened by the somewhat disappointing paper which 
had brought our veteran physicist to this meeting. 

QuEKETT Microscopical Club. — The 408th ordinary meeting 
was held on November 20th, at 20, Hanover Square, W., the 
Vice-President, J. G. Waller, Esq., F.s.A., in the chair. There 
was as usual a large attendance of members and visitors. Mr. 
W. H. Langton exhibited a small portable microscope, which he 
had constructed without the use of a lathe. It was fitted with 
sliding coarse adjustment, two-speed fine adjustment, and 
motions to stage, substage and mirror. The various adjustable 
parts were kept in alignment with the body of the instrument 
by means of grooves in the ring fittings, the grooved rings 
travelling on a steel wire fixed in alignment with the body tube. 
Mr. Langton was complimented by many members on the 
ingenuity displayed in the construction of the instrument. 

Mr. W. Wesch^ gave a demonstration, illustrated by the 
lantern, of the homology of the mouth partsof Dipterous flies with 
the mouth of the cockroach. It was shown how the mandibles 
were fused into the upper part of the proboscis of the blow-fly, 
and the maxillae, or inner jaws, embedded in the base. Mr. 
Weschc' also exhibited a number of minute palpi discovered by 
himself in many different species of Diptera. 

Mr. L. R. Gleason gave an address on bacteriology as 
considered from the point of view of the amateur. It was 
illustrated by lantern slides of cultures and apparatus, and by 
specimens under the microscope. He wished to correct the 
popular idea that very high powers and expensive apparatus 
were a sine qua non for bacteriological work. A great deal could 
be done with a |th-inch objective and a little ingenuity in the 
preparation of apparatus. He would not, of course, recommend 
the amateur to undertake the culture of pathogenic germs, but 
the non-pathogenic germs were quite as interesting to study, 
and, moreover, were in many cases of the highest value to man. 
Linen, hemp, tobacco, opium, butter, cream, cheese, and a host 
of other domestic products were produced by the action of these 
invisible workers, and he trusted that many microscopists in 
search of a field for study would turn their efforts in this 
direction. 

"Journal op the Quekett Microscopical Club."— The 
half-yearly number of this journal has just reached me, and 
contains several interesting and useful papers, amongst which I 
may mention Messrs. Marks and Wesche's " Further Observa- 
tions on Male Rotifers," and a second part of Mr. D. J. Scour- 
field's " Synopsis of the well-known species of British Fresh- 
water Entomostraca," dealing with the Copepoda. Mr. R. T. 
Lewis contributes a note on a hitherto undescribed species of 
Chelifer, illustrated by a plate ; and Mr. D. Bryce has a note 
on two new species of Philodina. Among the more popular 
articles may be mentioned Mr. W. H. Harris' " Remarks on 
the Emission of Musical Notes, and on the Hovering Habit of 
Eristalis tenux" ; and amongst practical notes one by Mr. H. J, 



Jascasy, 1901. 



KNOWLEDGE. 



21 



Quilter on " A ilethod of taking; [uternal Casts of Foraniinifera," 
which should prove useful to students, iiud might bo capable of 
extended application. 

AVatsox's ■■ Akhcs" MicROscoi'K. — .V cheap microscoiie may 
generally be looked ujion with suspicion, but Messrs. \V. Watson 
& Sons have just brought out a new microscope, which is not 
only cheap but of excellent workmanshi]i. The de.siL;n has 
several novel fejitnres. The limb is rigidly att.achad.to the 
stage, as in all Messrs. Watson's models, but the tine adjust 
ment is of the direct-acting micrometer screw type, actuated by 
an inverted head placed beneath the limb. The coarse adjust- 
ment is by means of a diagonally cut pinion which engages 
directly in the threads of the screw of this fine adjustment, 
there being another supporting wheel on tlie other side, so that 
one slide serves Ixith for coarse and tine adjustment. The foot 
is of the tripod pattern with a spread of nearly 7 inches ; the 
body is inclinable ; the stage is ^\ inches square ; and the body 
is provided with a draw-tube giving a variable tube-length of 
from ,5A to '.1 inches. The eyei)ieces arc the R.JI.S. standard 
Continental size, i.e., itlT.S inch. There are adjustable double 
mirrors, and a ring beneath the stage of the E.M.S. sfcvndard 
gauge, for condenser, I'cc. Compensating screws are provided 
for the working parts of the microscope. For this particular 
microscope Messrs. Watson have introduced a new series of 
objectives at specially low prices ; but of these I shall have 
more to say when 1 have had an opportunity of examining them 
personallj-. 

New Methoii of Mounting; Rotifkks. — I have recently 
seen some Rotifers mounted by a method which appears to me 
to have several novel points. The Rotifers, which were of the 
genus Megalotror/ia, are now more than two years old, but are 
as bright and clear a.s when first mounted. They were jiut up 
by Mr. W. Brockett, Laboratory A.ssistant in the Zoological 
Laboratories at ('ambridge, and I am indebted to him for the 
following explanation of his method. A few living Rotifers 
are put in a large drop of water on an ordinary slide. They are 
then narcotised by the addition to the water of a very few 
granules of cocaine. When perfectly extended, after examina- 
tion under a lens or a microscope, a drop of two per cent, 
osmic acid is placed on a clean cover-glass, which is then rapidly 
inverted and as quickly lowered on to the Rotifers. Actual 
contact, and therefore compression of the animals, is prevented 
by small pieces of gum label being stuck on the slip at each 
corner of the cover-glass, so as to make four small supports. 
The osmic acid is allowed to remain from one to three minutes, 
the progress of the staining being carefully watched under the 
microscope, after which distilled water is run under the cover- 
glass by the " irrigation " method. This is merely the ]ilacing 
of a small quantity of the irrigating fluid at one side of the 
cover-glass and applying a piece of blotting paper to the 
opposite side, bj- which means a current is .set up and the fluid 
drawn under the cover-glass. By the same method of irrig.i- 
tion, picro-carmine is then also drawn under, and allowed to 
stain for ten to thirty minutes, the progress of the staining 
being carefully watched as before. Finally, by the same 
method, there must be gradual dehydration with 30 percent., 
50 per cent., 7lt per cent., and 90 per cent, alcohols in the order 
given, after which follows clearing with the usual clearing 
agents, and mounting ("still Vjy the same method of irrigation) 
with balsam dissolved in absolute alcohol. The slides will then 
appear of a milky opacity, and be apparently useless, but should 
be put aside for twenty-four hours, when they will become 
clear and limpid. This clearing-up can be hastened by the 
application of moderate heat, but the risks are manifold. It 
will Vje noticed that an essential ])art of this method is the non- 
disturbance of the Rotifers from the time they were narcotised, 
and the drawing between cover-glass and .>'lip, of all the staining 
and dehydrating re-agents, and of the mounting medium, by the 
method of irrigation. 

MlcEO.scopiCAi- M.\TF,RIAL. — By the kindness of Mr. C. S. 
Ponlter, of Wallington, I am able to ofl'er to the microscopical 
readers of KnowleiiOE some leaves of /Miit^iu snihrii, showing 
stellate hairs, and of KIa(afinu< ediilin, showing peculiar scales. 
Those who desire to avail themselves of this material, should 
send me a stamped addressed envelope, together with the coupon 
appearing in the advertisement columns of this journal. 



NOTKS AND QUERIES. 

C. Judnoii. — There is no reason why the numerical aperture of 
suhstage condensers as well as of objectives should not he 
determined by the method described in Knowliuiue of 
November last. It should be borne in min<l, however, that the 
essential value of a condenser lies loss in its total aperture than 
in the aplanatic cone which it is capable of transmitting, namely, 
in that portion of its cone of light which is properly corrected. 
Thus the Abbe form of chromatic condenser with a numerical 
aperture of 1'-' or 1'4 N.A. has an aplanatic aperture of not 
more than •.'<, whilst the recent English achromatic condensers 
of 1 N.A. have aplanatic apertures varying from 9 to -dC) N.A., 
and immersion condensers of 14 N.A. may have apl.anatic 
apertures as high as IH N.A. An objecti%'e is a comjdicated 
combination of lenses, so that the rules by which the focal 
length of a single lens may bo determined do not apply to it, 
but what you probably require is not the focal length so much 
as the approximate equivalent focus, or, more definitely, the 
initial magnification. I hope to have a note dealing with these 
matters in the next issue of this Journal. 

I'liirer of Luroiitotioii ill Lophoptis rrj/stalliiiii.-<. — Mr. Willoughby 
Dade, of 13, Northbrook Road, Dublin, writes : - " There seems 
to be a division of opinion as to whether Lnjilinpiis /■ryslalliiitiK 
has power of locomotion or not. Indeed, most authorities say 
it has not. I have been keeping some colonies in a ten-inch 
Ijell-jar for some time, and am confident that they have this 
power. A short time since a group of about twenty individuals 
divided, and three or four days later the two colonies were fully 
a third of an inch apart, and now they are on different branches 
of a piece of milfoil. I find all the fresh-water Polyzoa in the 
Royal Canal here, excepting Alci/miella, which Allman says does 
not inhabit Ireland. Liijihuinix does very well in confinement, 
Crixtatflld only fairly well, but 1 am not successful with the 
tubed genera such as Pluiiititello repi'iix, I'dliulicidld, and 
Fre<lericeUa. These do not thrive, partly, I fancy, because 
Cyclopia appears to be fond of picking the polypides out. I 
should be very glad to know with what success other pond- 
hunters keep these animals in captivity." 

Ij. B. — It is exceedingly difficult to indicate the subjects, 
which would be likely to prove most interesting to you, in 
which the microscope could be used. There is so large a range, 
and every department dealt with intelligently provides such 
varied and interesting material for study and observation, that 
a knowledge of personal tastes and inclinations would be desir- 
able before recommending. In the " Knowledge Diary " for 
19l)4, obtainable from the publishers of this Journal, is an 
article entitled " Some Uses of the Microscope," which might 
prove of interest to you. It might be that on reflection you 
would prefer some other instrument, such as a telescope, in 
which case you would find the Diary referred to exceedingly 
valuable, for it contains : " The Heavens for 11)04," " An Astro- 
nomical Summary," " Practical Work of a Small Telescope," and 
other scientific information. 

T. Webster. — The publisher of Knowledge, to whom I have 
handed your letter, will lie able to inform you of a likely place 
to obtain a talde similar to that described by Mr. Morgan. The 
de.scription and illustration were intended to aid those who 
were interested in getting such a device constructed locally, 
but so many readers have enquired for a .source of supply that 
the publisher has taken the matter in hand. 

./. ./. .Macdoiiald. — It would be impossible to give any explicit 
direction as to the sizo of stop required to produce a black 
background without knowing the condenser and objective that 
were to be employed, together with the numerical apertures of 
both. It is likely that you are attempting to obtain a black 
background with an olijective possessing t<io large an N.A. 
Except the aperture of the objective be cut down, it is not 
convenient to obtain black ground illumination with numerical 
apertures in excess of '75. 

Communications and enquiries on M^icroscopical matters are 
cordially invited, and should be addressed to F. Snii.l.INOTON 
ScAi.KS, "Jersey,^' St. Barnabas Jiaad, Caiiiliridije. 



22 



KNOWLEDGE. 



[Januaby, 1904. 



Botanical Notes. — It is probable that the legeud 
respectiug the origin of the G-lastonburv Thorn is well 
known. How Joseph of Arimathea, in visiting Britain on 
a preaching mission, anive J wearv at Glastonbury, and while 
he rested, his hawthorn walking stick was thrust into the 
ground. How it at once began to grow, and ever after, so 
the legend savs, flowered on Christmas Day. The thorn is 
simply Cratcegti.'' 0.ryaca»tha precox, an earlv flowering 
variety of our common hawthorn. That it does flower 
remarkably early is quite true, for a tree in the Royal 
Botanic Clardeus, Kew, opens its flow-ers between November 
and March. This year it is now (early in Decemljerj bearing 
advanced flower-buds, which, had not the frosts injured 
them, would have expanded at Christmas time. 

Another part of " Hooker's Icones Plantarum " has just 
been issued, and this contains descriptions and figures of 
several especially noteworthy plants. Aniha megacarpa, 
seen in the fruiting stage only, might easily be mistaken 
for an oak (Quercus), iu which is found such remarkable 
variations in the cupules and acorns. This Aniha has a 
large, much-thickened cupule. and an oblong nut about 
three inches long. The genus belongs to the Laurineae. 
Rubber plants, to which an extensive literature is uow 
devoted, are met with in this part of the " Icones " in two 
species of Latulolphia and one of Sapiiim. Landolphia 
Kirkii is a very Important plant, commercially. In an 
interesting note on the manner of collecting the rubber, we 
are informed that it '" is collected in a way that is perhaps 
unique in any rubber-yielding plant. Some of the milk 
from a wound is allowed to coagulate. The pellet so 
obtained is applied to a fresh cut, and being turned with a 
rotary motion, the exuding milk is drawn off like silk 
from a cocoon. It is said that by working hard one person 
can collect five pounds of rubber per diem." In the other 
species of Landolphia figured, the rubber has to be 
coagulated bv heat. Both are natives of Tropical Africa. 
— S. A. S. 



THE FACE OF THE SKY FOR JANUARY. 

By W. Shackleton, f.e.a.s. 

The Sun. — On the 1st the sun rises at 8.8 and sets 
at 3.59 ; on the 31st he rises at 7.44 and sets at 4.43. 

Sunspots may now frequently be observed. 

The earth is at its least distance from the sun on the 
3rd ; the sun has then its maximum apparent diameter of 
32' 35"-2. 

The Moon: — 





Phases. 


H. M. 


Jan. 3 


O Full Moon 


5 47 A.M. 


9 


(T Last Quarter 


9 10 P.M. 


., 17 


% New Moon 


3 47 P.M. 


„ 25 


]) First Quarter 


8 41 P.M. 



The moon is in perigee on the 4th, and in apogee on 
the 19th. 

OccuLTATiONS. — The particulai's of the occupations of 
the brighter stars during the month are as folio >v : — 









Disappearance. 


Beappearance. 


aj 


1 


i 


s 


c 6 


4« 


a 
Is 

< 


M 


a . 

Is 

si 

5» 


h 


•< 
m 

g 
o 

g 




h. m. 


1 ° 


o 


b. m. 


o 


o 


d. h 


Jan. I in Tanri I o-2 


6 8 P.M. 


129 


170 


6 49 P.M. 


214 


2,V! 


13 21 


„ 3 26 Gemiuorum 


.VI 


1 34 A.M. 


1 66 


40 


, 2 .32 A.M. 


«« 


274 


15 4 


., 5 


o LeoDis 


a-8 


1013 P.M. 


129 


167 


11 9 p.m. 


2.i9 


?,95 


18 1 


■ > 26 


D.M + 12°436 


,=«■!» 


7 19 P.M. 


, 2.i 


16 


8 11 P.M. 


:iO!» 


ifSl 


9 4 


>. 28 


B.A.C. 15215 


5-8 


6 16 P.M. 


'. 7U 


99 


1 7 28 P.M. 


271 


W6 


11 3 


„ 30 


A Geluinoram 


36 


3 6 A.M. 


106 

1 


66 


4 3 am. 


275 


234 


12 11 



The Planets. — Mercury is an evening star in Capri- 
cornus. He is at greatest easterly elongation on the 1st, 
being 19''30 E., and sets for a few days near this time 
about H hours after the sun. On account of his great 
southerly dechnation, however, he is not favourably 
situated for easy observation. He is again in inferior 
conjunction with the sun on the 17th. 

Venus is a morning star, and rises on the 1st at 
4.22 A.M., and on the 31st at 5.28 a.m. Her brilliance, 
is, however, diminishing on account of increasing distance 
from the earth and greater southerly declination. 

Mars is low down in the south-west at sun-set, but is 
very feeble and badly placed for observation. 

Jupiter is on the meridian about sunset near the 
beginning of the month, whilst near the end of the month 
he sets about 9 p.m. 

The diameter of the planet is diminishing on account of 
his increasing distance from the earth, the polar and 
equatorial diameters being 34"'3 and 3(5"'7. 

The configurations of the satellites, as seen in an 
inverting telescope, and observing at 7 p.m., are as 
follow : — 



Bay. 


West. 


East. 


Day. 


West. 


East. 


1 


3 2 O 1 4 


17 


3 O 1 2 4 


2 


3 1 O 2 4 


18 


2 O 3 4 • 


3 


1 O 2 4 • 


19 


2 10 3 4 


4 


2 O 1 4 3 


20 


O 1 2 3 4 


5 


J O 4 3 


21 


1 3 O 2 4 


6 


4 O = 2 


22 


3 2 O 4 1 


7 


4 3 1 O 2 


23 


3 4 1 2 O 


8 


4 3 2 O 1 


24 


4 3 O 1 2 


9 


4 3 1 O 2 


25 


4 2 1 O 3 


10 


4 ® 2 • 


26 


4 2 3 


11 


4 2 O 3 • 


27 


4 O 1 2 3 


12 


4 2 1 O 3 


28 


4 1 ® 2 


13 


4 O 1 3 2 


29 


4 3 2 O 1 


14 


I O I 


30 


3^20 


15 


3 2 O 1 4 


31 


3 O J 2 


16 


3 1 O 4 • 







Tlie circle (O) represents Jupiter ; signifies that tlie 9at«llite is 
on the disc ; • signifies that the satellite is behind the disc, or in the 
shadow. The numbers are the numbers of the satellites. 

Saturn and Uranus are lost in the sun's rays and 

cannot be observed. 

Neptune comes to the meridian about 10.30 p.m., near 

the middle of the month ; being close to ft Greminorum, 

he can readilv be found by reference to that star, their 

respective positions on the 16th being : — 

Right Ascension. N. Declination. 

Neptune ... 6b. 17m. 16s. ... 22° 18'^ 31" 

ju. Geminonim .. 6h. 17m. lis. ... 22^ 33' 37" 
The planet therefore will be 15' directly south of the 



n> 




26^ 


24" 


^ o" 


1 b" 




2 


-^-,-^ 


■ 




f 


^! 


^[ 


•• 




'. 






1 


— t. \ 


• 


■ 




.• i. 








• 










^r^ 


















k22 






















« . 


. 


• 




M 


1 




. 










■ •• 


. • 










































^^l 








• 


. 




• 








. 


.- 


-6- 


C4." 


C l"" 






-■" 


.-^^l 



Chart showing path of Xeptune in 1904. 

star, and will appear in the same field of view with a 
not too high power eyepiece. The above chart shows the 
planet's path during the year 1904. 



.1a.m-.uiv, 1901.] 



KNOWLEDGE. 



23 



Metror Showers :-^ 



Date. 


Badiout. 


Name. 


Clmraoteristiis. 


R.A. 


Deo. 


Jan. 2-3 

1" 


o 

230 
21)5 


o 

+ 53 
+ 53 


Qviadrantids 
K Cygnids 


Swift ; long patlis 
Slow ; bright 



South 

West 

East 

North 



The Stars. — The positions of the principal constellations 
near the middle of the month at 9 p.m. are ;is follow : — 

Zenith . Perseus, Auriga (CapeUa). 

Pleiades, Taurus, Orion, witli Aries an<l Oehis 
towards the S.W., and Proci/im and Siriiis 
towards the S E. 
Pegasus, Andromeda, A(juarius and Pisces ; 

Cygnus to the N.W. 
Leo (Eeyulus) low down, Cancer, Gemini 

{Castor and PuUiix) liii,di up. 
Ursa Minor and Draco below Polaris, with 
Cassiopeia to the left and Ursa Major to 
the right. 
Minima of Algol may l)e observed on the 10th at 
1.21 A.M., 12th at 1(1.9 P.M., and on the 1.5th at 6.58 p.m. 

Telescopic Objkcts. — Nebulae. — Orion Nebula, situ- 
ated in the sword of Orion, and surrounding the niulti[>le 
stiir $, is the finest of all nebulsB, and is so bright that it 
can lie discerned with the naked eye ; with a 'S or 4-iuch 
telescope, it is best observed when low powers are em- 
ployed. 

Crab Nebula (M 1), in Taurus, situated about lj° 
north-west of K Tauri in R.A. 5h. 29m., Dec. 21° 58' N. 

Clusters. — il 37, situated in Auriga, is one of the finest 
clusters, and verv compact ; its position is R.A. 5h. 46m., 
Dec. 32^ 32' N. " 

Double Stars. — j3 Orionis (Rigelj, mags. 1 and 9, 
separation 9". On account of the brightness of the prin- 
cipal star, this double is a fair test for a good object- 
glass of about 3.inch aperture. 

S Orionis, mags. 2 and 7, se]iaration 53" ; easy double. 

K Orionis, triple, mags. 3, 6, and 10, separation 2"5 and 
50" ; rather difficult in a 3-inch telescope. 

A Orionis, mags. 4 and 6, sepai-ation 4"'5 ; pretty 
double. 

o" Orionis, triple, mags. 4, 8 and 7, separation 12"'5 and 
42". There are several other small stars near, and the 




Diagram of c Orionis. 

detection of the fainter ones is looked upon as a good test 
of the light-gathering power of the telescope. With a 
3-inch, one can see up to number 7, though 4 is very 
difficult. 



dbfss (Column. 

By C. D. LococK, h.a. 



Communications for this column should be addressed 
to C. D. IjOcook, Knowi.kduk Office, 326, High Holborn, 
and be posted by the 10th of each month. 



So 


l\itions of Dec'euiber Problems. 




No. 1 (W. Geary). 




K,;y-moi!fi.—\. B to B7. 




. K to B5, 2. Q to KBs(i, ch 
. ICt ( I5s(|) moves, 2. B x Kt. 
. P to K6, 2. Q to Q3cli. 

. . ]' to Q5, 2. Q to Ksq, ch. 

. . P to Kt5, 2. Q to (j4ch. 

. . Kt (Q3) moves, 2. Q to Q3 mate. 



If 1. 
1. 



No. 2 (C. D. Locock). 

Key-move. — ]. Kt to K8. 

. K to B4, 2. Q to R7. 

. KtoK6,orKt6, 2. QxPch. 



Solutions received from "Alpha," 4, 4; W. Nash, 4, 4; 
G. A. Forde (Major), 4, 4; "Looker-on," 4,3; G. VV. 
Middleton, 4, 4; " Quidam," 4, 4; J. W. Dixon, 4, 4; 
C. Johnston, 4, 4 ; H. S. Brandreth, 4, ; H. F. 
Culmer, 4, 4 ; T. Dale, 4, 4 ; J. Jones (Salford), 4, 4. 

"Looker-on." — After 1. Kt to B8 (which you give as 
an alternative to 1. Kt to R8), the defence K to B4 
appears to be good ; for if then 2. Q to R7, K x P. 
Many condolences on the loss of a point at the last and 
critical moment. 

H. S. Brandreth.— Aiter 1. B to Q5, K to B4 ; 2. Q to 
Bsq., K to Kt3. There is no mate. 

C. Johnston. — Many congratulations. Please send your 
full address. 

Result op Solution Tourney, 1903. 

Winner of the Knowledge Challenge Trophy. — C. 
Johnston, 83. 

Winner of Second Prize (15s.). — ^" Looker-ou " (G. J. 
Slater, Bolton), 82. 

Winner of Third Prize (Knowledge for 12 months). 
—J. W. Dixon, 81. 

These are closely followed by W. Nash and " Quidam," 
80. Other scores worthy of mention being : G. W. 
Middleton, 73; "Alpha," 68; H. F. Cuhuer, 64; G. A. 
Forde (Major), 62 ; and T. Dale, 58. Mr, Dale did not 
compete iluring tlio first three months, or he would 
evidently have taken a much higher place. 

The above award will remain open for one month. 

The sct)res of the first five show the closeness of the 
competition, the ri'sult of which was in doubt till tlie last. 
Last year Mr. " W. Jay " came out with a clear lead of 
four points. In the present competition the liolder of the 
trophy retired early, and Mr. C. Johnston, who tied for 
fourth place last year — 20 points behind Mr. .lay — scores 
a well-<ieserved success and becomes the second holder of 
the Challenge Trophy, "Looker-on" (Mr. G. J. Slater, the 
well-known composerj once more taking the .second place. 
Mr. Di.xon, winner of the third prize, did not compete last 
year. The same applies to " Quidam " ; Mr. W. Nash is 
a place lower. 



24 



KNOWLEDGE. 



[January, 1904. 



While syuipathiziug with "Lookerou" on his bad luck, 
the Chess Editor, who fully realized the difficulty of 
deciding what looked like a probable tie between two 
expert solvers, may perha[js be pardoned for congratulating 
himself on having effected a separation just in time to 
prevent the tie, by means of a problem specially composed 
for the occasion. He hopes that all last year's competitors, 
and many others, will take jiart in the new Solution Tourney 
which begins with the problems in the present number. 



PROBLEMS. 

No. 1. 
By A. H. Human. 

Black (8). 









i _..m m 



M, WM ^ § i 

WM' 'M& ^-'^f'-^ W^ 






M 9 m. 



M 



WniTE (P). 

White mates in two moves. 

No. 2. 
By J. C. Candy. 

Black (3). 






■mm. mm 



m * ^. 



H H 






I ■ 



White (5) 

White mates in three moves. 



SOLUTION TOURNEY, 1904. 

This year's Solution Tourney commences in the present 
number of Knowledgk, and will continue till the end of 
the year. The winner will hold for twelve mouths the 
Knowledge Challenge Trophy. This will become the 
property of any solver who wins it three years in succession, 
or four years altogether. In the event of a tie between 
the previous holder and another, the holder will retain 
possession of the trophy ; in that case, however, neither a 
win nor a loss will be scored to the holder. Should others 



than the holder tie for first place, the tie must be decided 
as below. 

The second prize will be 15s., and the third prize 
Knowledge for twelve months. In the event of ties for 
either or both of these, the ties shall be decided by a 
further trial of skill under new conditions, or the prizes 
divided at the discretion of the Chess Editor. 

The problems published will be either three-move or 
two-move direct mates, and not more than two will 
appear in any number. In the event of any problem being 
incorrectly printed, it will be cancelled and reprinted. 
Points will be awarded as follows : — 

Two-move Prohlems. — Aay one correct key, 2 points; 
a second solution, 1 point. 

Three-move Prohlems. — Any one correct key, i points ; 
a second solution, 2 points. 

One point will be deducted for any owe incorrect claim 
for a second solution. A correct claim of " no solution " 
will count as a correct key. 

Special Note. — Duals will not score. All solutions 
must bear ])ostmark of the issuing office not later than 
the 10th of the month of publication. 



CHESS INTELLIGENCE. 



The proposed match between Messrs. Blackburne and 
Marshall has been abandoned. Mr. Marshall is an 
enterprising player who aims high ; but matches between 
leading chess-players have always been notoriously difficult 
to arrange. Mr. Marshall has lately been annotating 
many of the games in the British Cheis Magazine, m the 
place of Mr. James Mason, who has been incapacitated by 
ill-health. At the time of writing we learn with regret 
that Mr. Mason has bad a serious relapse. All chess 
players will wish him a speedy recovery. 

Surrey defeated Sussex on November 21st, after a very 
closely contested match, by 85 games to 7A. The games 
on the four top boards were all drawn. Surrey lost on the 
next three boards, but their "tail" proved strong enough 
to outweigh this, and give them the victory. 



AU manuscripts should be addressed to the Editors of Knowledge, 326, High 
Holbom, London ; they should be easily legible or typewritten. All diagrams 
or drawings intended for reproduction, should be made in a good black 
medium on white card. While happy to consider unsolicited contributions, 
which should be accompanied by a stamped and addressed envelope, the 
Editors cannot be responsible for the loss of any MS. submitted, or for delay 
in its return, although every care will be taken of those sent. 

Communications for the Editors and Books for Eeview should be addressed 
Editors, KNOWLEnaE, 326, High Holbom, Loudon. 



SUBSCRIPTION.— Annual Subscription, throughout the world, 

79. 6d., post free. 
BOUND VOLUMES.— The yearly cloth-bound Volumes, Ss. 6d. ; 

postage extra. 
BINDING. — Subscribers' Numbers bound complete, 28. 6d. each 

Volume ; po3tage extra. Cases for Binding sold 

separately, Is. 6d. each ; postage extra. 
LANTERN SLIDES of many of the Plates appearing in Knowledge 

may be obtained from Messrs. Newton & Co., 3, Fleet 

Street, London. 
REMITTANCES.— All remittances should be made payable to the 

Publisher of Knowledge. 



For Contents of the Last Two Numbers of "Knowledge," 
Advertisement pages. 



see 



UDomledge & Selentifle Neiiis 

A MOXrillA JolRNAL OV SCll'NClL 



Vol. I. No. i. 



[new SERIES.] FEBRUARY, 1904. 



r Entered at "i 
LStalioners' Hall. J 



SixPKNCE. By Post, 7id. 



Introduction. 



As the announcement in the January number of 
" Knowledge " will have led our readers to ex- 
pect, certain new features appear in this the 
first issue of the combined papers " Knowi.eugi; & 
Illustrated Scientific News." These features, which 
were characteristic of the younger of the two periodicals, 
take the form of articles on Physics and .Vpplied Science ; 
and if they prove acceptable to our readers, we propose 
to add to them as time goes on other articles and notes 
dealing with the progress of science in Chemistry and 
Electricit}'. At the same time it is proposed to dis- 
continue none of the features which have been distin';tive 
of " Knowledge," and which during many years have 
secured for it so large and influential a body of readers. 
All the contributors whQse names were mentioned in the 
forecast which was published last December of the forth- 
coming volume of "Knowledge" have been retained, 
and their articles will appear during the ensuing twelve 
months. The Astronomical columns and their editorship 
wll remain under the able direction which has controlled 
them hitherto ; and the general articles and notes on 
Botany, Zoology, and Natural History will remain un- 
changed in general form and substance. The publication 
of the columns on Chess alone, it is proposed, owing to 
unavoidable circumstances, to postpone from this month 
until next, when a new announcement will be made. In 
concluding this brief notice of our intentions, we may ex- 
press the hope that they are such as to meet with the 
approval of our readers. 

Ancient Calendars a^nd 
Constella^tions. 



By li. Walter Maunder, F.R.A.S. 



It is generally asserted that the months of the year, both 
of the Accadian and Assyrian calendars, have an intimate 
connection with the constellations of the Zodiac ; the 
great epic of Gilgamesh has been claimed as a zodiacal 
myth ; and other myths and legends are explained in the 
same manner, or contain references which are apparently 
constellational. But we are thus sometimes involved in 
grave chronological difficulties, of which Assyriologists for 
the most part have taken no notice. It is therefore a 



very real service to science which the Hon. Miss Emmeline 
M. Plunket has rendered, '^ in that she has recognised one 
of the most serious of these discrepancies, has called 
attention to it, and has striven to remove it. 

The chief astrological work of Assyria is one in 70 
tablets, drawn up for the library of King Sargon of 
Agane. The date at first assigned to this monarch was 
about 1700 B.C., for it was concluded that before this 
date the month Nisan, the first month of the Assyrian 
calendar, could not have corresponded with the position 
of the spring equinox in the first sign of the Zodiac, Aries. 
Later, however, a baked clay cylinder of Nabonidus, King 
of Babylon, who reigned from 555 — 538 B.C., was dis- 
covered, in which he described iiow he rebuilt the temple 
of the sun god at Sippar, and in the course of the work 
had found an inscription of Naram-Sin, the son of 
Sargon 1., the original founder of the temple, " which for 
3200 years had not been seen." From this tablet a little 
simple arithmetic led to the conclusion that the date of 
Sargon must ha\-e been about 3800 n.c. 

These two determinations of the date of Sargon differ, 
it will be seen, by at least two thousand years ; that is to 
say, by more than the entire length of the Christian era. 
The second determination of course follows inevitably, if 
we take the statement of Nabonidus at its face \alue. 
The first determination is equally inevitable if certain 
underlying assumptions are made. But both detentiina- 
tions cannot be right ; a period of 2000 years cannot be 
treated as a negligeable quantity. Assyriologists in 
general stand by the date for Sargon of 3800 B.C. as " the 
best determined date in ancient history." ^'et the obvious 
consequence has not been recognised, or at least not been 
practically admitted; namely, that the assumptions upon 
which the date of 1700 e.g. were based must, some or all 
of them, be incorrect. They still sometimes enter, ex- 
plicitly or implicitly, into Assyriological papers without 
the slightest hint being afforded that so grave a doubt 
has been cast on their validity. 

The assumption with which Miss Plunket deals is the 
one that the Accadian year originally began with the 
sun's entry into the zodiacal constellation Aries at the 
spring e(iuinox. For spring etjuinox she would substitute 
winter solstice, and thus throw back the origin of the 
Accadian Calendar by 6400 years, to some date prior to 
the year 6600 b.c. 

This suggestion is the text of Miss I'luiiket's book, 
which consists of eight papers communicated at different 
times to the Society of Biblical .\rcha'olcgy, followed by 
notes explaining the numerous illustrative plates. She 
applies this principle to the explanation of the astronomy 
and mythology of Assyria, Media, Egypt, India, and 
China, displaying much research and not a little ingenuity 
in some of her explanations. 



' " Ancient Calendars and Conslella lions.' 
line M. Plunlset, (John Mtjrray.) 



By the Hon. limme- 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



But it is not necessary to examine her arguments in 
detail. The objections to her fundamental principle are 
too serious. In the first place we may be very confident 
that the starting point of the original year was not fixed 
at a solstice. The difficulty to the first beginners in 
astronomical observation of determining the solstice 
must have been very great. For more than an entire 
month the sun does not alter its declination by a single 
degree ; its places of rising and setting, its height at noon, 
show scarcely any change. But when we turn to the 
equinoxes we find a very different state of things. At 
that time three days make a greater difference in the 
sun's declination than thirty at the solstice. The height 
of the sun at noon changes from one day to the next by 
three-fourths of the sun's diameter. The most careless 
observers could not fail to recognise that either equinox 
was a point of time which could be determined with very 
great ease and precision. At these times of the year, too, 
and at these alone, the place of sunrise is precisely oppo- 
site the place of sunset. By half-a-dozen methods, all of 
the greatest simplicity, the time of the equinox could be 
fixed to a day. 

Then it is not the case, as Miss Plunket avers, that 
Aries was the traditional constellation to lead the year. 
It is curious that some of the traditions which speak of a 
time when Taurus opened the year are expressly 
quoted by Miss Plunket. The familiar lines of Virgil 
in the first Georgic are an instance. Prof. Sayce, in the 
very same paper as that which Miss Plunket takes as her 
authority, quotes Ernest de Bunsen, "That Scorpio was 
taken as the starting point of the primitive Calendar," 
and Scorpio, of course, holds the same position with 
regard to the autumnal equinox that Taurus, not Aries, 
does to the vernal. 

Miss Plunket, at the beginning of her fourth chapter, 
recognises that the great importance of Tauric symbolism 
in Median art seems to point to the fact that when the 
equinoctial year was first established, the spring equinoc- 
tial point was in the constellation Taurus, and she 
quotes Cumont to show that the great festivities in 
honour of Mithra were, asa rule, celebrated at the season 
of the spring equinox. Most opportunely a translation 
by Mr. Thomas J. McCormack has just appeared of 
Cumont's " Mysteries of Mithra," in which he gives a 
clear and most interesting account of the cult of Mithraism 
and of its distribution in Europe." The illustrations of 
the book render one fact of Mithraism very conspicuous ; 
its intimate connection with the constellational figures, 
and especially with the signs of the Zodiac. In par- 
ticular, the Bull, the Scorpion, the Lion, and the Man, 
the four constellations of the colures when Taurus held 
the vernal equinox, are the great Mithraic symbols. Yet 
most of these symbols extant were actually carved in the 
second century a.d., when their appropriateness to the 
four seasons had been completely lost. 

But the vital objection to Miss Plunket's theory is that 
it assigns to the constellations an antiquity greater by 
some thousands of years than they can possibly possess. 
This is a point I have already taken up elsewhere, and I 
need only summarise the arguments here : — 

(i) The centre of the space not included in the 
ancient constellations must have been the south pole 
of the period when they were designed. This gives 
roughly the date 2H00 n.c. 

(2) This date accortls with the tradition of the 



• " The Mysteries olMithra " tSy t'ranz Cumont. Translated 
by T. J. McCormack. (Chicago : Tlie Open Court Publishing Co. 
London ; Kegan Paul.) 



four Royal stars — Aldebaran, Regulus, Antares, 
Fomalhaut — marking the original colures. 

(3) It gives the only symmetrical position for the 
actual constellations of the Zodiac. 

(4) The ascending signs at this date faced east, 
the descending west. 

(5) As shown above, there are traditions of Taurus 
leading the' Zodiac; but there are none of Gemini, 
Cancer, or of any earlier sign. 

Thus as to season and constellation and date, we must 
find Miss Plunket in error. But beside this error in prin- 
ciple there are several errors in detail, either as to astro- 
nomical fact or in computation. 

Thus, for example, we find in the preface, p. viii., the 
times when the equinox entered Aries and Taurus, quoted 
from Prof. Sayce, as 2540 and 4698 b.c. respectively, 
but on p. 66 and elsewhere these dates are given as 2000 
and 4000. These are not the only instances of a consider- 
able looseness in dealing with the subject of precession. 
Thus, on page 37, Miss Plunket speaks of the stars of 
Aries attaining the southern meridian at midnight, two 
months after the summer solstice, between the years 1 100 
and 1400 B.C. Actually the constellation Pisces held that 
position. On pp. 166 and 167 the star Spica is said to 
have been in opposition to the sun on the 14th night of 
the first month at the time of the Exodus. This fixes 
the date of the Exodus as about 1300 years after Christ, 
i.e., in the time of the Plantagenets ! 

There should be no very great difficulty in understand- 
ing the effect of precession. If we take the entire pre- 
cessional period as 25,800 years, we find that the longitude 
of any star must increase one degree in 7i§ years. It is 
then a matter of the very simplest arithmetic to find out 
what star at any time was on the equinoctial colure, that 
is to say in zero longitude, and what were the longitudes 
of other stars. 

So far from Aries having been the equinoctial sign as 
early as 2540 b.c, the first zodiacal star of the constella- 
tion about which we can be at all sure did not hold that 
position till 1650 b.c. The equinoctial point was still in 
the Pleiades — undoubtedly a portion of Taurus — as late 
as 2200 B.C., and iVldebaran, " the eye of the Bull," and 
the very central star of the constellation, was on the 
colure 3000 B.C. The earliest undoubted bright star of 
Taurus, Zeta Tauri, the tip of the southern horn, was in 
zero longitude 4080 b.c 

We can see at once why we have no tradition of the 
constellation of the Twins opening the year. The con- 
stellations were certainly mapped out much later than 
40S0 B.C. But the real difficulty, and it is a very impor- 
tant one, is to explain how it was that Aries came to be 
looked upon as the first sign at a comparatively early 
date. If we take the date 1650 b.c, for instance, the 
sun was then in conjunction with Delta Arietis (a star 
but little brighter than the 5th magnitude) at the spring 
equinox. But it was also in conjunction at the same 
date with Xi Tauri and Omicron Tauri, considerably 
brighter stars, and for practically one full month after 
the spring ecjuinox the sun would be travelling through 
Taurus. It is not possible to conceive that at this 
period, when men had always from the very first begin- 
ning of astronomy been accustomed to regard Taurus as 
the first sign, they decided to give the primacy to Aries. 
It would be so easy for them still to consider Taurus as 
reaching to this point, which indeed it overlaps, and on 
any view, even if they considered the sun as in Aries on 
the actual first day of spring, four days later it would be 
unmistakably in Taurus. Practically the sun at the 
spring equinox was still at the first point of Taurus, and 
there was no need to make any change of the first sign. 



Feb., 1904.] 



KNOWLHDCIK c^- SCII'XTIFIC NEWS. 



Vet we may be sure that it would be only uiulcr sonic- 
thing like compulsion that the change would be made, 
for we see how tenacious men are of old traditions by 
our own case, since we still speak of the hrst point ot 
Aries, although the equinox has almost traversed the 
entire length of Pisces. It is almost universally for- 
gotten that it was not until the equinox had been brought 
by the effect of precession right through a sign, to its 
very boundary, that that particular sign was in its true 
position to correspond with the iirst month of tiie year. 
The equinoctial point moves through the centuries by 
the effect of precession in the direction of diminishing 
longitudes; the sun in its annual course through the 
year moves in the direction of increasing longitudes. 

It could not have been early, therefore, in the period 
which precession would ascribe to Aries that the primacy 
was transferred to that constellation. It is scarcely con- 
ceivable that it can have been l)efore Ilamal, the huida 
of the constellation, had reached the cohire, which it did 
about 700 B.C. There are no bright stars between Delta 
Arietis and Hamal ; there is nothing whatsoever to have 
compelled an abandonment of a primeval custom. Indeed, 
it seems to me that there is only one theory by which we 
can account for the transference of the dignity of leader 
from the Bull to the Ram. If in the course of time the 
science of astronomy fell into abeyance, possibly through 
wars and revolutions and the conflicts of races, and all 
that remained was just the recognition of the old con- 
stellation forms which might well have been preserved 
by the peasantry, and then at a later date the science was 
built up anew, the position of Aries as the leader con- 
stellation would be perfectly natural. Bui if so, whilst 
we must take 2800 B.C., or perhaps, to speak in rounder 
numbers, 3000 B.C., as the time of the rise of the first 
astronomy, with Taurus as leader, the time of its 
revival with Aries as leader can hardly have antedated 
700 B.C. 

If, then, we find a poem or myth, evidently based upon 
the Ram-Zodiac, we may be fully assured that the date 
of its first origin w-as certainly not earlier than 700 B.C., 
and probably considerably later. For a myth is not likely 
to have taken thorough hold upon men's imaginations 
immediately after the acceptance of a novel scientific 
system, to explain which that myth had been imagined. 
Such a process is necessarily one of slow development. 

I will take but one illustration ; the epic of Gilgamesh 
has been sometimes claimed as a solar legend on account 
of a supposed connection between the twelve successive 
tablets which contain it, and the twelve signs of the 
Zodiac. The hero is the sun, and the epic describes his 
progress through the twelve signs in the course of a year, 
the eleventh tablet which gives the account of the Deluge 
corresponding to the constellation Aquarius, the eleventh 
sign of the Ram-Zodiac. But Assyriologists would not 
be willing to admit that the Deluge Story was no older 
than the eighth century B.C. It follows, therefore, that 
the original Deluge poem must have been written when 
Aquarius was the tenth sign of the Zodiac, so that the 
legend cannot be interpreted as a poetic expression of the 
constellation figure. What applies to one sign applies to 
the rest, and the entire correlation imagined between epic 
and Zodiac breaks down at every point. 

The question on which we have no light at present is 
as to the steps of the evolution, or the character of the 
catastrophe by which the Bull-Zodiac was superseded by 
the Ram-Zodiac. We can only be sure of one point, that, 
given the connection between the constellations and the 
months of the year which is usually assumed, then the 
Ram-Zodiac must be of comparatively modern times ; 
later, probably a good deal later, than 700 B.C. 



A Motor AeroploLFve, 

Sviccessful Trials witK a Ma>.rv- 
Ca.rrying Machine. 



Many of our readers have tloubtless been keenly inter- 
ested in some of the experiments now being conducted 
in luigland, and especially in .Vmerica, with Hying 
machines. Hitherto but little success has attendeil the 
efforts of inventors, and though on a few occasions a 
model has shown its power of progressing through the 
air, yet all attempts to raise a man from the ground have 
proved abortive. 

Various vague and sensational accounts have appeared 
in the Press durmg the last few weeks of a most impor- 
tant experiment made in .America by the brothers Wright. 
We are now able to give an authentic account, kindly 
sent by Mr. Orville Wright himself, of what actually 
occurred. He states that he had not intended at present 
making any public statement with regard to the trials, 
but that "newspaper men " gave out "a fictitious story 
incorrect in almost every detail," so that the inventors 
feel impelled to make some corrections. The real facts 
were as follows : - • 

On the morning of December 17, between the hours of 
10.30 o'clock and noon, four flights were made, two by 
Orville Wright and two by Wilbur Wright. The starts 
were all made from a point on the levels and about 
200 feet west of our camp, which is located a quarter of a 
mile north of the Kill Devil sand hill, in Dare County, 
North Carolina. The wind at the time of the flights had 
a velocity of 27 miles an hour at 10 o'clock, and 24 miles 
an hour at noon, as recorded by the anemometer at the 
Kitty Hawk weather bureau station. This anemometer 
is 30 feet from the ground. Our own measurements, 
made with a hand anemometer at a height of four feet 
from the ground, showed a velocity of about 22 miles 
w-hen the first flight was made, and 2oi miles at the time 
of the last one. The flights were directly against the 
wind. Each time the machine started from the level 
ground by its own power alone with no assistance from 
gravity, or any other sources whatever. After a rim of 
about 40 feet along a mono-rail track, which held the 
machine eight inches from the ground, it rose from the 
track and under the direction of the operator climbed 
upward on an inclined course till a height of eight or ten 
feet from the groimd was reached, after which the course 
was kept as near horizontal as the wind gusts and the 
limited skill of the operator would permit. Into the teeth 
of a December gale the " Flyer" made its way forward 
with a speed of ten miles an hour over the ground and 
30 to 35 miles an hour through the air. It had previously 
been decided that for reasons of personal safety these 
first trials should be made as close to the ground as 
possible. The height chosen was scarcely sufficient for 
mancEuvring in so gusty a wind and with no previous 
acquaintance with the conduct of the machine and its 
controlling mechanisms. Consequently the first flight 
was short. The succeeding flights rapidly increased in 
length, and at the fourth trial a flight of 59 seconds was 
made, in which time the machine flew a little more than 
a half mile through the air, and a distance of 852 feet over 
the ground. The landing was due to a slight error of 
judgment on the part of the operator. v\fter passing over 
a little hummock of sand, in attempting to bring the 
machine down to the desired height, the operator turned 
the rudder too far, and the machine turned downward 
more quickly than had been expected. The reverse 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



movement of the rudder was a fi action of a second too 
late to prevent the machine from touching the ground and 
thus ending the flight. The wiiole occurrence occupied 
httle, if any more, than one second of time. 

( )nly those who are acquainted with practical aeronau- 
tics can appreciate the difficulties of attempting the first 
trials of a flying machine in a 25-mile gale. As winter 
was already well set in, we should have postponed our 
trials to a more fa\ourable season, but for the fact that 
we were determined, before returning home, to know 
whether the machine possessed sufficient power to fly, 
sufficient strength to withstand the shock of landings, and 
sufficient capacity of control to make flij^ht safe in bois- 
terous winds, as well as in calm air. When these points 
had been definitely established, we at once packed our 



A Wright Machine— A side view. 

goods and returned home, knowing that the age of the 
flying machine had come at last. 

From the beginning we have employed entirely new 
principles of control ; and as all the e.xperiments have 
been conducted at our owm e.xpense, without assistance 
from any individual or institution, we do not feel ready 
at present to give out any pictures or detailed description 
of the machine. 

It may be mentioned that the Messrs. Wright have for 
some years been conducting a series of experiments with 
" gliding machines," that is to say aeroplanes without 
any engine or propeller. With them the operator starts 
from the top of a hill and glides down through the air to 
the bottom, thus having to balance and control the 
machine. 

We gi\ e here an illustration of one of the gliders, which 
is probably very similar to the machine recently tried, but 
the latter apparently had a motor and propeller added. 

^.^^^^^ 
Electrical Novelties- 



Giant and Miniature 
S\ins. 



By J. E. Gore, F.R.A.S. 




Messrs. F. Darton and Co.'s list of electrical novelties, just 
published, is remarkable for the cheapness of most of the 
articles which this firm supplies. The novelties include 
house telephones, hand gears and hand-geared dynamos for 
demonstration purposes, and their vvell-Unovvn small dynamos 
for working with small oilengines. This firm also has'a num- 
l)er of attractive small electric light sets and economical 
motors for fans and light electric power work. 



It was at one time thought a probable hypothesis that 
the stars were in general of approximately equal size and 
brightness, and that their difference in brilliancy de- 
pended chiefly on their relative distance from the earth. 
On this apparently plausible hypothesis, we should have 
— taking the accepted " light ratio" of 2-512 — an average 
star of the first magnitude equal in brightness to 100 
stars of tfie sixth magnitude. As light varies 
inversely as the square of the distance, this 
would imply that a star of the sixth magnitude 
— that is one just steadily visible to average 
eyesight in a clear and moonless sky — would 
be ten times farther from the earth than a 
star of the first magnitude. For the same 
reason, a star of the eleventh magnitude would 
be at ten times the distance of a star of the 
sixth magnitude, and therefore 100 times the 
distance of one of the first magnitude. .'\n 
eleventh magnitude star is about the faintest 
just steadily visible with a telescope of 3 inches 
aperture. For stars of the sixteenth magni- 
tude, or about the faintest visible in a 25-inch 
refractor, the distance would be — on the above 
hypothesis — 1000 times the distance of a first 
magnitude star. 

Although this hypothesis was plausible 
enough at first sight, there never was any 
real evidence to show that the stars are 01 
equal size and brightness, and modern re- 
searches ha\e proved that they differ greatly 
in absolute size, and also in intrinsic brilliancy 
of surface. Measures of distance have shown 
conclusively that several small stars are considerably 
nearer to us than some bright stars, such as .^returns, 
\'ega, Capella, Rigel, and Canopus. These brilliant 
orbs must therefore be vastly larger than the faint 
stars which show a larger parallax. On the other 
hand, we have reason to believe that many stars are 
much smaller than our Sun. A consideration of some 
of these giant and miniature suns, as they may be termed, 
may prove of interest to the general reader. 

We will first consider some of the "giant" suns. 
The well-known reddish star Aldebaran (a Tauri) in the 
Hyades maybe taken as a standard star of the first mag- 
nitude. A small parallax of o'loy of a second of arc was 
recently found for it at Yale College Observatory (U.S.A.). 
This makes its distance from the earth about seven times 
that of a Centauri (of which the parallax is o"-75). Now, 
as Aldebaran has the same spectrum (K 5 M, Pickering) 
as the fainter component of a Centauri (magnitude i'75i, 
the two stars may be considered as fairly comparable in 
intrinsic brightness. From the above data I find that 
Aldebaran is about 92 times brighter than the companion 
of a Centauri and its mass about S82 times greater. But 
the components of a Centauri are of equal mass, and each 
equal in mass to our Sun. Hence Aldebaran has prob- 
ably a mass 882 times greater than that of the Sun ! 

The red southern star Antares (a Scorpii) is of magnitude 
I -22, according to the most recent measures at Harvard 
Observatory, and its parallax, according to Sir David Gill, 
is about o"-o2i. Comparing with Aldebaran, we have the 
latter 1159 times brighter. But Antares is at five times 



Feb., 1904.] 



KNOWLEDGE i^- SCIENTIFIC NEWS. 



the distance of Aldebaran. Hence the real brightness of 

Antares will be -^ , or 21-5 times greater than that of 

1-159 
Aldebaran. The surface of Antares would therefore be 
21-5 multiplied by 92, or 197S times the surface of the 
companion of a Centauri, and its mass about <SS,ooo times 
the mass of the Sun — a truly giant orb ! 

Betelgeuse (a Orionis) has a similar spectrum to 
Antares, but as it is brighter and its distance greater it 
is probably larger still. 

Rigel ( Orionis). Assuming a parallax of o"-oi fovmd 
by Sir David Gill, and comparing it with the hvi<:;htey 
component of a Centauri, which is of nearly the same 
apparent (or stellar) magnitude, we have, since the 
parallax of a Centauri is o"'75, 

Light of Rigel = 75- = 5625 times light of the Sun 
(which is probably the same as that of a, Centauri). But 
the spectrum of Rigel shows that it is hotter and brighter 
than our Sun. The two bodies are therefore not exactly 
comparable, and we must make an allowance for their 
difference in intrinsic brightness. If we assume that the 
Sun's light is reduced by absorption in its gaseous sur- 
roundings to one-fourth of its real light — which is 
probably a liberal allowance — we have, 

Surface of Rigel = -' — - = 1406 times surface of Sun. 
4 
From this it would follow that the volume of Rigel is 
about 52,000 times that of the Sun. Rigel is, however, 
probably of less density than our Sun, owing to its higher 
temperature. Comparing it with Algol, which has a 
similar spectrum, and of which the density and mass are 
known, we have the surprising result that the mass of 
Rigel is about 20,000 times the mass of the Sun ! The 
parallax of Rigel is, of course, somewhat doubtful, but 
Sir David Gill is confident that it does not exceed the 
small quantity above stated. 

For ^ Centauri, Gill found a parallax of o"-046. Placed 
at the distance indicated, the Sun would shine as a star of 
about 6-75 magnitude, and as the photometric magnitude 
of the star is o-86, we have a difference of 5-89 magnitude, 
which would make jS Centauri 227 times brighter than 
the Sun. This gives a volume 3420 times the Sun's 
volume, and assuming the density at one fourth of the 
Sun's, we obtam a mass for ^ Centauri equal to 855 times 
the Sun's mass ! 

Crucis is of almost exactly the same brightness as 
Aldebaran, but it is at double the distance from us, a 
parallax of only o"-05 having been found by Gill. Its 
spectrum (of the ■' Orion type") indicates, however, that 
it is a much hotter and brighter body than Aldebaran. 
Taking its greater distance into account, we may perhaps 
conclude that it is comparable in size with Aldebaran, 
and therefore a sun of great size. The star P Crucis, 
whose stellar magnitude is i'50, but which has no measur- 
able parallax, must also be a giant sun. Its spectrum is 
the same as that of « Crucis. 

Arcturus and Pollux have similarspectra (K, Pickering). 
The photometric magnitude of Arcturus is 0-24 and that 
of Pollux I-2I. The parallax of Arcturus, as found at 
Yale Observatory, is o"-o26, and that of Pollux o"-05r). 
From these data it would follow that Arcturus is 
11^ times brighter than Pollux. The Sun placed at the 
distance of Arcturus would shine as a star of about the 
eighth magnitude, or about 7-7 magnitudes fainter than 
Arcturus appears to us. This would imply that Arcturus 
is about 1200 times brighter than the Sun. It must there- 
fore be a sun of gigantic size — probably one of the largest 
bodies in the universe. The above calculation would 
make Pollux about 100 times brighter than the Sun. 



The bright stars Canopus and Procyon have \ery 
similar spectra, but the parallax of Canopus does not 
exceed o"'Oi, while tliat of Procyon is about o"'32. Still 
Canopus is a brighter star, its photometric magnitude being 
— 0'86, while that of Procyon is + 0-48, a difiercnce of 
I '34 magnitudes in favour of Canopus. From these 
data 1 find that Canopus is 3500 times brighter than 
Procyon, and it follows tliat its volume is 207,000 times 
the volume of Procyon ! If the densities are the same, 
the masses will be in this ratio, and as the mass of 
Procyon, as computed from the orbit of its satellite, is 
about five times the mass of the Sun, we have the mass 
of Canopus more than that of a million of suns ! This 
is probably the largest sun of which we know anything. 
Sir David Gill's observations show that the parallax of 
Canopus does not exceed the hundredth of a second as 
above stated. A smaller parallax would, of course, 
further increase its size. 

The observations of "spectroscopic binary stars" en- 
able us to determine their mass although their distance 
from us may remain unknown. As their actual orbital 
velocity can be measured with the spectroscope in miles 
per second, their distance from the earth is a matter of 
no importance in the computation of their mass. One of 
the most remarkable of these interesting objects is the 
southern variable star known as V Puppis. It is a 
variable of the Algol type, and also a spectroscopic 
binary. The plane of the orbit must therefore neces- 
sarily pass through the earth, or nearly so, and the mass 
of the system can be easily computed. The spectro- 
scopic observations show the enormous relative velocity 
of 380 miles a second ! and indicate a mass equal to about 
70 times the mass of the Sun. The variation of the star's 
light shows, according to Dr. A. W. Roberts, that the 
component stars revolve round each other in actual con- 
tact, or nearly so, and that their mean density cannot 
exceed i-5oth of the Sun's density, or about 0-028 that of 
water. With such a small density and so large a mass 
the components must evidently be greatly expanded 
masses of gas, probably several millions of miles in 
diameter. The period of revolution is about 34 hours 
54 minutes, a wonderfully short period for a pair of 
suns ! 

Let us now consider some suns of probably miniature 
size. The star Lalande 21,185 (7'5 magnitude) in the 
constellation Ursa Major has a parallax of about o"-47. 
At the distance indicated by this comparatively large 
parallax, the Sun would shine as a star of about 17 mag- 
nitude, or over 200 times brighter than Lalande's star. 
iVnother small star in the same constellation, Lalande 
21,258 (8-5 magnitude), has a parallax of o"'24. This 
distance would reduce the Sun to about 3-2 magnitude, 
but it would still be 5-3 magnitudes, or over 130 times 
brighter than the star. 

The small star Argelander-Oeltzen 17,415 of the 9th 
magnitude has a parallax of o"-25. The Sun, if placed 
in the same position, would be over 200 times brighter 
than the star. 

Another small star with a comparatively large parallax 
is Lacaille 9352. Its magnitude is 7-1, and the parallax 
about o"-29. The Sun, if placed at the distance indicated 
by this parallax, would shine as a star of about 27 mag- 
nitude. This gives a difference of 4-4 magnitudes, and 
implies that the Sun is over 50 times brighter than the 
star. This star has the very large proper motion of 7" per 
annum. It is a remarkable fact that the faint stars above 
mentioned are actually nearer to the earth than Aldebaran, 
which is one of the brightest stars in the sky. 

The famous double star 61 Cygni is also probably of 
! small mass. Taking its parallax at o"-39, the Sun, if 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



placed at the same distance, would be reduced to a star 
of about 2-1 magnitudes, and as the photometric magni- 
tude of 61 Cygni is about 5-1, we have a difference of 3 
magnitudes in favour of the Sun. This makes the Sun 
nearly 16 times brighter than fii Cygni, and would indi- 
cate that it has about 60 times the mass of the star. The 
spectrum of 61 Cygni is of the second or solar type, but 
not exactly similar to that of the Sun. 

Some of the faint satellites to bright stars (mentioned 
in my paper on "Stellar Satellites") must be either bodies 
of small mass or slight luminosity. Take the case of 
Burnham's 14th magnitude satellite to Aldebaran. As- 
suming that its parallax is the same as that of Aldebaran, 
or about one-tenth of a second, we have the Sun reduced 
to a star of the 5th magnitude at the same distance. 
This would make the Sun 9 magnitudes, or about 4000 
times brighter than this faint star ! It must therefore be 
either a comparatively small body, or else it must have 
proceeded a long way on the road to the total extinction 
of its light. If we suppose the density and surface 
brilliancy to be similar, the ratio of the masses would be 
about 25,000 to I, and this small star would be less than 
14,000 miles in diameter. It seems highly improbable 
that a body so much smaller than the planet Jupiter 
should continue for long in the sun-like stage. More 
probably it is a "cooled down sun." If its mass is not 
miniature, its light is certainly small. 

The sun if placed at the distance of Regulus would 
shine with about the same brilliancy as the 8i magnitude 
satellite to that bright star. This satellite has close to it 
a faint companion satellite of the 13th magnitude. As 
both are moving through space with Regulus they are 
evidently physically connected with the bright star and 
lie at the same distance from the earth. This 13th 
magnitude star is therefore 4^ magnitudes, or over 60 
times fainter than the Sun. The accuracy of the small 
parallax found for Regulus (o"-022) may perhaps be 
doubted, but there can be no doubt, owing to the common 
proper motion of all three stars, that Regulus and the 
faint satellite are at practically the same distance from 
the earth. The great difference in their light — nearly 12 
magnitudes — indicates that Regulus is about 46,000 times 
brighter than its faint attendant. There must therefore 
be an enormous difference either in their size or the 
luminosity of their surface. 

The measures of the double star « Urscc Majoris show 
that it is a binary star. There is a difference of at least 
9 magnitudes between the components, showing that 
one is at least 4000 times brighter than the other. Con- 
siderable difference in size or great discrepancy in surface 
brightness is therefore absolutely certain. 

The bright star 7 Draconis (2^ magnitude) has a faint 
companion of the 13th magnitude which seems to be 
travelling with it through space. The difference of loi 
magnitudes between the two implies that one is at least 
10,000 times brighter than the other. Their disparity in 
mass or inecpality in surface brightness must therefore 
be enormous. 

Although calculation shows that the companions of 
Sirius and Procyon are each equal to the Sun in mass, 
still, as far as luminosity is concerned, they may be con- 
sidered as miniature, or at least minor, suns. If the Sun 
were placed at the distance of Sirius it would shine as 
bright as the Pole Star, whereas the Sirian satellite is 
only of the loth magnitude, or nearly 1300 times fainter 
than the Sun. In the case of Procyon, the Sun placed 
in the same position would l)eover 16,000 times brighter 
than the faint attendant. These small stars are probably 
"cooled down suns'' which are verging towards the total 
extinction of their light. 



Another somewhat similar case is that of the binary 
companion to the star 40 (o-) Eridani. This small binary 
star is of the 9th magnitude, while the primary star is 
about 4J. As both have a common proper motion 
through space they are evidently physically connected, 
and therefore lie at practically the same distance from 
the earth. I'rofessor Asaph Hall found a parallax of 
o"-22 for the brighter star. Assuming this parallax for 
the binary pair, I find from Burnham's orbit a combined 
mass equal to o'yi of the Sun's mass. Placed at the 
same distance the Sun would shine as a star of 3-28 mag- 
nitude, that is 572 magnitudes, or 194 times, brighter 
than the binary, which therefore seems to be another 
sun, or rather a pair of suns, on the road to extinction. 

The globular clusters, composed as they are of such 
faint stars, suggest the inevitable conclusion that either 
the components are miniature in size, or else that these 
wonderful objects lie at a vast distance from the earth. 
Even an approximate distance has not been found for 
any of them. If we assume a parallax of Jjyth to jJinth of 
a second — 163 to 326 years' journey for light — the com- 
ponent stars of most of. them would be considerably 
fainter than our Sun would be if placed at the same dis- 
tance. On this assumption they would be relatively 
small bodies. On the other hand, if we assume a parallax 
of ,A,,th to i,'„„th of a second — from 1600 to 3200 years' 
light journey — the Sun would be reduced to about the 
I ^;\ to 15th magnitude, and this would make the compo- 
nent stars equal to or brighter than the Sun. That each 
of the stars which compose these clusters is e(iual to our 
Sun in size and brightness seems improbable, and perhaps 
the most likely supposition is that they are comparatively 
small bodies, and are not so far from the earth as is 
sometimes supposed. 

Ceylon 
Pearl Oyster Fisheries. 

Professor Herdman's Report to 
the Colonial Government. 



In 1801 the Island of Ceylon became definitively a liritish 
possession, and with the removal of Dutch power there 
passed into English hands the control and the proceeds 
of the "pearl oyster" fisheries. Since the occupation 
of the Island its pearl banks have, it is computed, brought 
over one million pounds sterling into the treasury chest 
of the Government. 

Although the aggregate amount derived from the 
Ceylon fisheries is suggestive of a prosperous mainte- 
nance of the native industry, in reality the situation has 
long afforded ground for disturbing conclusions. In the 
year 1S91 there was an extraordinarily abundant oyster 
yield, the estimated revenue bemg placed at one million 
rupees, whereas ensuing periods have demonstrated hut 
a dismal tale of fishery failures. There was, however, 
a good fishery last year (1903). Theories and specula- 
tions have been put forth from time to time regarding 
the phenomena of these strange oyster disappearances, 
but comparatively little which might tend to throw real 
light upon the question has resulted from the discussions. 

In such circumstances and mindful of the probable 
recurrence of conditions likely to profoundly modify or 
even jeopardise the pearl fishery, the Colonial Government 
determined in 1900 to seek outside and expert aid with 
the view of elucidating the scientific and economic 



Feis., 1904.] 



KXcn\LEDGl-: c^ SCIl'XTll'lC xi:\\s. 



problems that were involved, and accordingly com- 
missioned Professor \\'. A. Herdman, F.R.S., of the 
Natural History Department of the rni\ersity of 
Liverpool, to proceed to Ceylon, in company with a 
qualified scientific assistant, to commence a survey and 
carry out a series of investigations and experiments. 
The steamship Liuiy Hiizvloik was placed by the Ceylon 
authorities at Professor Herdman's disposal for the work 
of examining the biological surroundings of the pearl 
oyster banks, and during two successive cruises of three 
or four weeks e.ach he inspected out at sea all the prin- 
cipal banks, established lines of dredging and trawling, 
and made observations across, around, and between the 
banks in order to ascertain the conditions that satisfy an 
oyster " paar," the term applied to the varied rocky 
strata (as opposed to shifting sandy layers) beneath the 
water which constitute the habitat of the animal. In all 




iNative Divers employed by l*rof. Herdman. 

these operations the Professor found an able coad- 
jutor in Mr, James Hornell, his assistant, who, it 
may be added, is still in Ceylon furthering the 
enquiry. Enough, however, has already been 
accomplished to permit the issueof a detailed report 
embracing a description of the banks, and a record 
of the studies that were made on the life-history 
of the pearl oyster itself. The accompanying illus- 
trations we are privileged to reproduce from this 
Report, 

Much virtue often attaches to a name, but in the 
case of the so-called pearl oyster we have to disabuse 
our mind of any lingering belief that it is a true 
oyster, since, as a matter of fact, the animal belongs 
to the family Aviculidse, and is therefore more 
nearly related to the Mussels [Mytiliis) than to the 
Oysters {Ostraa) of British seas. One character 
in particular marks it ofT from Ostraa, namely, 
the ownership of a " byssus," or bundle of tough 
threads, by means of which it can tag itself on 
to rocks or other adjacent objects, as do its con- 



geners, the Mussels, The species has favoured Ceylon 
waters, or, more strictly, tlie shores of the Culf of Manaar 
on the north-west, in countless generations from icnioti' 
antiquity, hence, long prior to ICuropean rule ; while the 
praises of the "orient" pearl ha\-e been unilnrmiy e\- 




A Bunch of Oysters from the sea hotloni. Four generations are seen. 

I he iarpest is xi years old, anJ the smallest, attached to the 

lart^e shell, is about a month old. 

tolled in many a classical allusion. .\li over the district 
the pearl oyster of the banks is the same animal, a 
decision that was quickly arrived at by Professor 
Herdni:in ; lurthermDre, the method of fishery now pur- 
sued, even to the manning of the divers' boats and the 
custom of the cessation of diving at noon, is a continua- 
tion of ancient practice. 

Of the causes which lead up to the disappearance of 
the oyster population — sometimes in hundreds of thou- 
sands — and the de\-astation of the banks, the Commis- 
sioner has much to say that is of interest. Influences 
such as oceanic currents, monsoon storms, and shifting 
sands have each their play ; added to wliich, in common 
with other classes of marine denizens, the pearl oyster 
has its enemies. Boring sponges may destroy the shell, 
and boring molluscs suck out the animal. Then there 
are the star-fishes and carnivorous fishes to reckon with. 
But, as Professor PIcrdman remarks, compensation arises 




One (tf the enemies 



Half natural si/e. 



8 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



in these matters ; for instance, one foe, a Plectognathid 
fish, which possibly devours very many oysters, at the 
same time receives and passes on the parasite whicli 
results in the production of pearls in others. 

The life-cycle of the pearl oyster is described from the 
egg onwards to the adult animal, and the story unfolded 



excrescences on the interior of the shell were detected as 
being due to the irritation caused by boring sponges and 
burrowing worms, but the minute grains of sand or other 
internal particles popularly supposed to form the nuclei 
of pearls are considered only to do so under exceptional 
circumstances. The majority of the best gems, on the 




Three transplanted Oysters showinjj rapid growth. I 

II. New'shell formed in 21 days. III. Oy 

is one of singular interest. Margaritifera vulgaris was, in 
fact, most seriously studied ; partly in miniature experi- 
mental tanks, with the first aid of the microscope ; again, 
in the hauls of the tow-net ; and by means of diving 
trials at the sea depths, where, it may be noted, the 
oyster occurs on the rocky bottom in 5 to 10 fathoms of' 




The dotted line indicates the new shell formed— 23 days, 
star showing a month's growth — Natural size. 

contrary, are caused by the stimulation of a parasitic worm 
which becomes encased and dies. And this parasite is 
the Cestode larval Tdrarhijnchits. Professor Herdman 
purposes dealing with this aspect of the question of 
pearl-formation at greater length later on. 

Finally, there is one general conclusion that is reached 
in this opportune and admirable Report, and it is all-im- 
portant. \Ve are told that there is no reason for any feeling 
of despondency in regard to the future of the pearl fisheries 
of Ceylon if they are treated scientifically. Adult oysters 
are plentiful on some of the paars and seem for the most 
part healthy and vigorous ; while young oysters in their 
first year and masses of minute spat just deposited are 
very abundant in many places. " The material exists, 
ready for man's operations." 

[.According to a Times telegram from Colombo on December 
gth, 190J, Captain Legge, Master .-Xttendant, on his return from 
inspecting the pearl banks, has decided against the proposed 
fishery this year. The next fishery will be in February, 1905.J 

Astronomical Notes* 



Valuation sample of Pearl Oysters in course of delivery from 
the inspection boats. 

water. In the vicinity of the Manaar Gulf pearl banks 
this element is so clear that under the rays of a high sun 
the depths are brilliantly illuminated. A passing shadow 
will cause the animals to immediately snap-to their 
valves. 

As regards pearl -formation, some pearls or pearly 



Sir W. Ramsay on New Gases and Radium. 

Sir William Ramsay addressed the British .Astronomical 
.Association on December 30, on the subject of " Stars and 
Atoms." In the earlier part of his lecture he recounted the 
history of the discovery of the new gases, .Argon, Helium. 
Neon. Xenon, and Krj'pton, exhibiting representations of 
their spectra, and explaining their places in the periodic 
series. He dwelt specially on the last-named gas with refe- 
rence to its connection with Aurorre, and showed that the 
principal line in the auroral spectrum was the chief line 
of Krypton. Passing then to the discovery of radium, he 
described the properties of this element, including the three 
kinds of rays that it gives off, and suggested that we might 
find an analogy to the constitution of the molecule of this, the 
densest of all known elements, if we imagined a closely aggre- 
gated solar system, or better still, a stellar cluster, in which 
the collisions were frequent, or at least the perturbations 
often excessive, leading to the continual loss by the system of 
members whose velocities thus attained a greater than the 
critical. Such instability, he suggested, would be only per- 
ceptible in the case of unusually dense elements. 



Feb., 1904.] 



KNOwLi'iHii' .V scii':x rii-ic xi:\vs. 



5olar Activity and Terrestrial Magnetism. 

The principal subject of the papers at the Ivoyal Astrono- 
mical Society, on January 8, 1904, related to the connection 
between solar activity and terrestrial nia.sjnetisni. Mr. William 
KUis pointed out an annual inequality in the frequency of 
aurora; as observed in these latitudes, correspondini; to that 
established in the frequency of magnetic disturbances. Mr. 
Maunder drew attention to the two great periods of excep- 
tional solar quiescence, and suggested a connection with the 
secular change of magnetic declination. Mr. M.iundcr 
examined the details of the nineteen greatest magnetic storms, 
since 1S75, and the nineteen greatest sun spots, and suggested 
that the action from disturbed regions on the Sun might have 
a maximum eftect in a given direction, and that this would 
explain quantitative discrepancies between certain sunspots 
and the magnetic storms which appeared to synchronise with 
them. 

Stellar Magnitude of the Sun. 

Mr. Charles Fabry, at the meeting of the Paris .'\cademic 
des Sciences on December 2S, 1903, communicated the result 
of his photometric determination of the stellar magnitude of 
the Sun. On December 7 he had reported that he found the 
Sun's light to be 100,000 times more intense than that produced 
by a decimal candle at a distance of one metre. A similar in- 
vestigation, with the star \'ega as the subject, gave the stars 
light as equal to that of a decimal candle at "So metres. The 
stellar magnitude of Vega being taken as 0-2, that of the Sun 
was inferred to be — 26'7. 

Double Spiral Structure in Hercules. 

Professor J. M. Schaeberle, in the Astruiiumical Jaiiriui!. 
No. 552, announces his discovery of a double spiral structure 
in the great cluster in Hercules, the more pronounced spiral 
being clockwise, the other being counter-clockwise ; the clock- 
wise spiral being formed by the inner streams of ouli^oiti)^ 
matter, the seeming counter-clockwise spiral by that part of 
each stream which contains retiiniiug matter. The plane of 
the spiral is not normal to the line of sight. A precisely 
similar structure on a much larger scale appears to 
exist in the stars and nebulosity surrounding Gamma 
CassiopeitE. 

Botanical Notes. 



A New Rubber Plant. 

Another plant containing rubber is now arousing con- 
siderable interest in Colorado, according to Mr. T. D. A. 
Cockerell's paper in the Bulletin of the Colorado College 
Museum, No. i, where a description of the plant is given 
under the name of Picradenia Jloribunda utilis. It is a 
native plant, belonging to a North American genus of 
Composita^ and resembles in appearance the French 
marigold genus (Tagetes), to which it is allied. Unlike 
most of the previously known rubber plants, this is a 
rather dwarf herb, and the rubber is obtained, not from 
a woody stem, but from the roots, where it is found in 
large quantities. 

A New (ienus. 

A curious new genus is described in the Japanese 
Botanical Magazine for September, 1903, to wiiich the 
name Miyoshia has been given. The only species at 
present known is a small, saprophytic, leafless plant, 
quite destitute of chlorophyll. It was found in a forest 
in the province of Mino, Japan. The author considers 
the genus to be closely related to Aletris in Liliaceae, but 
as he cannot fit it into any already established order he 
has putit into a new one, which hehas called Miyoshiacea'. 
The tubeless perianth and semi-inferior ovary suggest 
some Ha;modoracea;. 

Root Formation. 

In the Osterreichishe Botanische Zeitschrijt for December, 
1903, Leopold Ritter von Portheim records his observa- 
tions on root-formation on the cotyledons of Phaseolus 



vulgaris. Experiments with beans carried on for five 
years before 1901 were unsuccessful, but in that year the 
desired results were obtained in eleven cases. The plants 
were grown in tliedark in distilled water or in a nutritive 
solution free from lime. Roots developed, sometimes 
one, sometimes two or three, on the cotyledons near the 
attachment to the a.\is. It was also found that roots, 
and less frequently shoots, would form on cotyledons 
separated from the axis, but it was not quite clear whether 
the shoots were auxiliary or not, in spite of the careful 
separation of the cotyledons. 

British Orrvithological Notes. 



Tin: column in Knowledge hitherto devoted to British 
(Ornithological Notes, and conducted by Mr. Harry F. 
W'itherby, will, we regret to say, be now discontinued. 
Mr. Witherby wishes us to convey his sincere regrets 
to our readers that this course has been found necessary, 
and that no longer notice could be given. 

REVIEWS OF BOOKS. 



"The Evolution of Barth Structure, with a theory of geomor- 
phic changes." By T. Mellard Reade, F.G.S., F.R.I. B.A., 
A.M.I.C.F. Pp. xvi. + 3.|2. (London: Longmans, Green, 
and Co., ujoj; price 21s. net.) Mr. Mellard Keade, with his 
long experience as an architect and engineer, has never lost an 
opportunity of applying physical principles to the explanation 
of the structure of the earth. His well known thermal theory 
of the origin of mountain ranges is discussed in our geological 
text-books; and he has been a consistent believer in the ade- 
(juacy of subsidence and elevation in explaining the main 
problems of our Pleistocene deposits. In the present work, 
he has not attempted a continuous argument, but has brought 
together a number of papers and experimental observations 
which bear upon the development of the present surface of the 
earth. Mr. Reade does not shrink from controversy, but his 
methods of inquiry are always sympathetic. He relies (p. a) 
on fluctuations of temperature in the earth's crust in account- 
ing for surface-movements, diflerences of specific gravity, and 
local increases or decreases of volume, being thereby set up in 
the outer layers. A diagram (plate i) illustrates his views on 
the formation of laccolites and batholites, by the expansion 
and melting of portions of the igneous shell which underlies 
the sedimentary series. We do not understand the •' 5956 
miles" which are marked on this plate near the centre; of the 
earth, and we are tempted to suspect the whole, on account of 
its obvious simplification. The serious reader of this book 
will come to it, however, well prepared, and will probably ac- 
cept Mr. Osmond Fisher's permanently liquid layer, quite as 
readily as Mr. Reade's " semi-plastic underlying shell." 
Having shown how the vertical uplift of continental platforms, 
and the vertical falling in of oceanic basins, may be brought 
about, the author considers the local wrinklings in these areas, 
such as have produced our mountain chains. He attributes 
the tangential creep (p. 45) to the transference of material by 
denudation from one place to another, promoting subsidence, 
heating of the lower layers, and lateral expansion, with 
consequent crumpling of the strata. But Mr. Keade urges, 
and we think very wisely, that the alleged permanence of 
continents and oceans does not rest on geological evi- 
dence, when we extend our view over a sufficient lapse of 
time. ' He emphasises the occurrence of considerable and 
even mountainous irregularities in the floors of our present 
oceans, and denies that the edge of the continental plateaux 
represents any marked break between continental and oceanic 
forms (p. 103). The scarp so often noticed is aptly compared 
to the outer end of an artificial embankment formed by 
tipping, the dcbns from the land l)eing largely responsible for 
what are often styled "submerged platforms." 



10 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1 904. 



The experimental models, by which mountain-structure is 
made to arise in circular circumscribed areas, are of wide 
interest (pp. 131-215), and lead to some criticism of the views 
of Suess on the potency of differential subsidence to produce 
the oceanic depths and the high continental masses. 

Chapter XIX., on Slaty-Cleavage, descends somewhat from 
geomorphology to petrology; the interestinj; details have been 
already pul)lished by the Liverpool Geological Society. The 
volume also contains a paper on the denudation of America, in 
which the relations of continents and oceans are again dis- 
cussed; and a final and lucid statement of the case against 
those who have asserted the permanence of these larger 
features of our globe. 

The geological reader and the librarian will not consider the 
price of Mr. Keade's book high, when once they have turned 
it over, and have noted the numerous original ilhistrations. 
which in themselves give it a permanent value. 

Galileo: His Life and Worli, l\y J.J. Fahie. (London: John 
Murray, Albemarle Street, W., UJ03 ; i6s. net.) Mr. I'"ahie 
has succeeded in giving a very life-lilic and attractive 
picture of the great philosopher. His restless energy of 
investigation, his keenness of observation, his affection and 
generosity to his relatives and friends (many of whom were 
most undeserving), and the biting wit with which he attacked 
his enemies are brought vi\idly before us. The last named 
(|uality was his ruin, and, far more than any novelty or heresy 
in the doctrines be taught, brought upon him the bitter perse- 
cutions from which he suffered. His real crime was that he 
made his opponents a laughing-stock, and Pope Urban \Tn, 
believed that he too had been " made game of." He had 
given Galileo an argument against the proof which Galileo 
considered the most cogent in establishing the motion of the 
earth round the sun. Galileo placed that argument in the 
mouth of Simplicio, the representative of the Ptolemaic 
philosophy in the great " Dialogue," and the Pope regarded 
this as equivalent to saying that he was a " simpleton." 
Curiously enough this same irrefragable proof — the argument 
from the tides — is untenable, so that the Pope's objection has 
been justified by the result, though his mode of reasoning was 
unscientific. 

Galileo's attitude of mind towards science was quite different 
from that of his contemporaries. As a result of this, his life 
was one of brilliant scientific triumphs, but also of unceasing 
conflict and bitter suffering, relieved, however, until the last 
eight years of his life, by the touching and romantic devotion 
of his noble-hearted daughter, \'irginia. His is a heroic 
figure, and it as a hero that Mr. Fahie has treated him ; the 
one fault to be found with his portrayal of him l)eing that, like 
the Aristotelians of Galileo's day, he will not allow that there 
can be any spots on his sun, for he supports Galileo where 
he least deserves support, namely in his refusal to allow any 
merit to rival and independent workers in the same fields, such 
as Lippershay, Scheiner, and Marias. 

The SoLltness of the 
Deocd Sea. 



Two causes, says Mr. William Ackroyd, in the report of 
the Palestine Exploration Fund, have been assigned to 
account for the saltness of the Dead Sea. The first of 
these is the accumulation of chlorides, which soh-ent 
denudation derives from the rocks of the Holy Land. 
The second e.xplanation is that an arm of the Red Sea 
was cut off by the rising of Palestine in prehistoric a^es, 
and in either or both cases the saltness would have been 
intensified by evaporation. 'J'here remains, however, to 
be taken into consideration a third cause — the atmo- 
spheric transportation of salt from the Mediterranean. 
This may not improbably be a more potent factor than 
either of the other two causes of the Dead Sea's saltness. 
The salt which the winds carry inland from the sea falls 
in rain and is carried back again to the sea; but in the 



case of an inland lake without outlet it remains for evapo- 
ration, so much so that in the case of a Pennine reservoir 
water equally salt with that of the Dead Sea would be 
produced by this means in a fraction of the time usually 
assigned to the Pleistocene Age. Taking specimens of 
the rocks on which Jerusalem is built as samples of the 
Palestine rocks, they are found to be limestones of 
various compositions, and with the one exception of Kakule 
limestone, which contains 0-025 per cent, of chlorine, or 
o'04.i of common salt, the chlorine contained in these 
rocks approximates to the general average of that found 
in the limestones of other countries of o-oi per cent. 
This percentage would be quite inadequate to account 
for the salt in the Dead Sea, and the salt yielded to 
rivers by denudation is not a ninety-ninth part of that 
which has been supplied by rain water. Nor would the 
saltness of the Dead Sea be fully accounted for if a marine 
area had been cut off during the rising of the land, as the 
initial saltness thus acquired would only be about a 
fourth of that subsequently attained to ; and, moreover, 
in this condition of saturation it has been for an unknown 
length of time continually precipitating its excess of salt. 
The intensity of meteorological conditions in the past 
geological history of Palestine have been much more 
severe than those now obtaining, and the atmospheric 
transportation of salt would be correspondingly greater. 
Some of the salt then accumulated has been left by the 
dwindling waters of the Dead Sea in areas to the north 
and south, notably in Jebel Usdum, and the highly 
brackish rivulets which come from these neighbourhoods 
now are but contributing again what long ago came from 
more distant sources. 



The Nebulosities round 
/ Cygni. 



];y Dr. Max Wolf, F.R.A.S. 



1 DISCOVERED these large nebulous masses in iSgi.andon 
several occasions have published photographs of them. 
Some two and a half years ago I was fortunate enough 
to get a fairly good picture of them with my sixteen 
inches Brashear lens, which I hope may prove of interest 
to the readers of" Knowledge & Scientific News." The 
accompanying plate has been made from a contact print 
from the original photograph, which was exposed for 
nearly seven hours, on the nights of July 16 and 17, igoi. 

The bright star involved in nebulosity in the centre of 
the plate is y Cygni. The star, a Cygni, is not included 
in the plate, but would lie a little outside it, at the left 
upper corner. The nebulous stream running diagonally 
across the plate, in the line joining y Cygni and a Cygni 
is very distinctly shown. But the most striking feature 
of this region is furnished by the broken nebulosities 
near the centre of the plate. The contrast, too, afforded 
by the crowds of stars and the nebulous masses is very 
remarkable. In some places all are mixed together, 
bright stars, small stars, and nebulosity ; whilst in others 
the intervals between the stars are entirely free from nebu- 
losity. Very striking, too, are the irregular dark holes in 
the nebulosity to the west of 7 Cygni, and the clouds to 
the east, and north-west of that star. A curious straight 
line of stars crosses the plate north of the centre. 

The scale of the plate is 32 millimetres to one degree 
of arc. 



"Kxoin.KDQK * SoiESTlFic ^Csa'S."— February. 19(M. 



NORTH. 



0) 

< 







THE NEBULOSITIES ROUND v CYGNI. 



— 



Feb,, 1904,] 



KNOWLEDGE cS: SCIENTIFIC NEWS. 



II 



The Ancestry of the 
Elephants, 

By A. Smith W'oodwakh, LL.D., I'.K.S. 



LoxG before the ancestry of the horses and camels liad 
been discovered in North America, some of the im- 
mediate fore-runners of the elephants had been.reco^'nised 
and discussed in the Old World. The disco\eries of 
Falconer and Cautley in India, of Falconer, Gaudry, and 
others in fiurope, had made it evident that the elephant 
was derived by gradual stages from a more normal kind of 
quadruped. These gradations, however, could only be 
traced back as far as the Middle Miocene period, and no 
known animal of earlier date could be claimed as ancestral 
to the series. Lower Miocene and Eocene quadrupeds 
continued to be discovered in abundance, but never any 
trace of an elephantoid creature. The natural conclusion 
therefore was that the race of elephant-like animals only 
reached Europe and .\sia in the early part of the Miocene 
period by migration from some other region in which the 
early stages of their tribal history were passed. It e\entu- 
ally became probable that the .\frican continent would 



or trunk. It is, in short, the story of a rare wliicli once 
fed in a normal manner on succulent weeds, browsing like 
any other herbivore, but afterwards began to subsist on 
drier or harder vegetation, and at the same tiiiK- lost the 
power of reaching the ground witii its mouth, depending 
for help on a modification of the snoul which is elsewhere 
unknown. 

The oldest recognised member of this race is the small 
Moefitlicriiini (lig. i) from the Middle Ivocciie of I'-gypt. 
It comprises species not much larger than the existing 
tapirs, and they possess a neck sufficiently long and 
tlexible to have allowed theui to browse in the ordinary 
way. The skull of Moivithcriitui shows that it did not 
support more than a rudimentary proboscis, but there are 
certain features in its structure which suggest a tendency 
towards arrangements now specially characteristic of the 
elephants proper. The teeth are disposed in a long scries, 
and are nearly as numerous as in any of the early ijuadru- 
peds. In the upper jaw there are the usual three pairs 
of front cutting teetii or incisors, but the second pair is 





Fig. I. — Sloeritherium byomi , left side-view of skull, upper view of 
mandible Ia|. and diagrammatic section of last molar tooth (B). — 
Middle Eocene ; Eg\-pt. 

yield these ancestors, and students of extinct animals 
began to look with confidence to that part of the world. 
Their expectations have not been disappointed ; for the 
recently-published researches of Dr. Charles \V. Andrews 
on early Tertiary Mammalia from Egypt" have furnished 
precisely the missing links that were desired. The evolu- 
tion of the elephant-tribe is now almost as well known as 
that of the horses, camels, and their allies ; and Africa is 
proved to have been its ancestral home. 

The body of the elephant has changed very little during 
its long geological history. It has always retained the 
simple limbs with five toes and unaltered wrist and ankle. 
It has merely become a little shortened in proportion to 
its height, while the supporting limbs have grown in 
stoutness as the successive representatives of the tribe 
have increased in size and weight. In fact, it is permis- 
sible to describe the massive frame of a modern elephant 
as essentially an overgrown copy of the skeleton of a 
herbivorous quadruped of the early Eocene period. 

All the features which make elephants unique among 
Mammalia are therefore to be obser\ed in the head and 
neck. The story of their evolution is concerned mainly 
with the gradual enlargement of their tusks and com- 
plicated grinding teeth, and with the eventual grow'th of 
a peculiarly flexible, boneless, and prehensile prolongation 
of the face, which is commonly known as the proboscis 



I-"l<i. z.—Paliioviastodon headncUi : left side-view of skull, upper view of 
mandible (a), and diagrammatic section of last mohir tooth IB.) — 
Upper Eocene ; Kyypt. 

much larger than the others, and forms conspicuous 
downwardly-curved tusks. Small canines, or corner 
teeth, are also present; and there are six grinding teeth 
on either side (three pre-molars and three molars), most 
of them bearing two cross-ridges, the hindermost also 
with a third small posterior ridge (fig. ib). The lower 
jaw (fig. ia) likewise has six grinding teeth, of which the 
molars closely resemble those of the upper jaw ; but 
canine teeth are absent, and there are only two pairs of 
incisors, the outer pair being mucli the larger. The jaws 




" " On the Evolution of the I'roboscidea, 
pp. 99-1 iS. 



I'bil. Trans , 19031;, 



Section lb. 



are narrow, but there is no conspicuous prolongation of 
the chin (or mandibular symphysis). 

The next genus, from the Upper Eocene of ICgypt, is 
much more clearly elephant-like. It is named I'alao- 
maitodon (fig. 2), and comprises species somewhat more 
than twice as large as any of the earlier kinds of Moeri- 
thcriiim. A peculiar elongation of tlie skull and a long, 
spout-shaped growth of the bone of the chin (mandibular 
symphysis) are now very noticeable, and all the incisor 
teeth except one pair have disappeared above and below_ 



12 



KNOWLEDGE & SCIENTIFIC NEWS. 



Tep.., 1904. 



The surviving upper incisors are rather large tusks, and 
have lost all the enamel except a narrow band on one 
face — exactly like the front teeth of a gnawing animal 
(Rodent). The lower incisors are at the end of the chin 
far in front of the upper tusks, and they are still more 
like the incisors of a rodent (fig. 2a). They have a band 
of enamel on their lower face, and they are worn to a 
chisel-shaped edge by some opposing hard substance — 




ones take their place ; and these teeth exhibit greater 
complication than before, the posterior molar at least bear- 
ing four cross-ridges, with a rudiment of a fifth ridge 

(fig- 3^)- 

There is not much doubt that, with so remarkably 

elongated a head, Tdrahelodon would be able to browse on 
or near the ground, notwithstanding the length of its legs 
and the shortness of its neck. However, the shape of the 
skull shows that, even if the animal did not 
need a proboscis, the arrangement of the 
soft parts of its face and nose must have 
closely resembled this prehensile organ in 
a modern elephant. The outline of the head 
is, indeed, fancifully given in the accom- 
panying fig. 6 ; and from this it is evident 
that the only hindrance to the use of the 
snout as a typical proboscis is the immensely 
elongated bony chin which underlies it. 

Towards the close of the Miocene period 
many of the "mastodons," as these animals 



perhaps a pad on the palate. The grinding teetli of the 
upper jaw are as numerous as in Mocritherium, and those 
of the lower jaw are only reduced by the loss of another 
front pre-molar. The three molars, however, are rela- 
tively larger and more complicated than in the earlier 
genus, each bearing three cross-ridges, the hindermost 
also with a rudimentary fourth ridge (fig. 2b). 




Fig. 2.—Telrabelodon angustidens ; left side-view of skull, upper view of mandible (Aj and diagrammatic section of last molar 

tooth (B). — Middle Miocene; Europe. 



The elephant-like quadrupeds continued to live in 
Africa from the Eocene period to the present day, but, 
probably through some re-arrangement of land and sea, 
they also wandered into Europe in the early part of the 
Miocene period, and soon afterwards penetrated even to 
the extreme eastern limits of Asia. The European and 
Indian members of the race during these later periods are 
indeed better known than those from Africa itself, and 
they must be referred to for information concerning the 
Miocene and Pliocene developments. 

In the Middle Miocene, as shown by Tdrahdodoii 
anguslidens (fig. 3), the hinder part of the skull becomes 
short and deep, the upper tusks and their sockets are 



are generally termed, actually lost their bony chin by 
the shortening of the lower jaw. The soft snout being 
then destitute of support of any kind, must have begun 
to droop downwards ; and there is thus no difficulty in 
understanding how it eventually became the essential 
feature of the modern elephants. 

Some of the short-chinned species which form the genus 




longer than in any earlier genus, and the spout-like 
mandibular symphysis, with chisel-shaped incisors at the 
tip, is more elongated than ever (fig. 3A). The grinding 
teeth are now so large that not more than two or three on 
each side of the jaw are in use at any one time, the front 
grinders being pushed out of the mouth as the hinder 



fYW\) 



Fig. .?b. 



Feb., 1904.] 



KNOWLEDGE & SCIENTIFIC 



Mastodon of the Upper Miocene and Lower Pliocene 
periods in the Old World, of the Pliocene and Pleistocene 
periods in America, are provided with grinding teeth 
scarcely njore complicated than those of the earlier 
Tetrabdodoii. Their upper tusks also difier only from 
those of tiie latter in ha\ing lost the band of enamel 




l-"JO. .\. — Stegodon ganesa ; Icfl side-view 
of sl<ull. — Lower Pliocene; India. 



(All figures much reduced, as indicated by fractions. 



14 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



outside the ivory. Their lower tusks, however, are merely 
functionless rudiments, often lost when the animals are 
full grown. 

At the same time it is interesting to observe, that as 
soon as the shortened chin and unsupported face had 
become characteristic of the " mastodons," true elephants 
with deep and ridged grinding teeth made their appearance 
at least in the Indian region, and quickly spread over all 
the Old World. The tusks of some species (rig. 4) now 
grew to immense size. The cross-ridges of the grinding 
teeth (fig. 5b) also became more numerous, and so much 
deepened and compressed that they might rather be 
described as plates ; while the inconvenient crevices 
between them were filled for the first time with a third 
kind of tooth- substance, which is rather soft, termed 
cement. In the Lower Pliocene Stc/^odon, as the earliest 
true elephant is named, large grinding teeth, consisting 
of alternating cross-bands of hard and soft tooth-sub- 
stance, were thus fully fashioned. 

The later elephants and those of the present day only 
differ from each other in minor characters, and in the 
degree of compression or multiplication of the plates of 
their grinding teeth. The maximum complexity of tooth- 





Fig. 5a. 

structure is reached in some of the hairy elephants, or 
mammoths (fig. 5) of the Pleistocene period, which ranged 
far north, even within the Arctic Circle, and may often 
have been compelled to feed on specially hard and dry 
vegetation. Their grinders (fig. 5B) are much deepened, 
capable of withstanding many years of wear in the mouth ; 
and the numerous plates of which the posterior grinders 
are composed would hardly be recognised as simple 
tooth-ridges if all the initial stages in their evolution now 
described were not forthcoming. 

The general conclusion, therefore, is that the history of 
the elepliant is analogous to that of the other tribes of 
hoofed animals which culminated in the horses and tiie 
cattle. They ha\e grown from mere creatures of the 
marshes to roam over the plains, or through forests, and 
haveat the same time gradually acquired deeper and more 
effective grinding teeth. For some inexplicable reason, 
the lengthening of their legs with a concomitant shorten- 
ing of their neck, necessitated a unitjue elongation of their 
face and chin to reach the ground for browsing. When 
this strange makeshift had reached its maximum degree, 
the chin suddenly shrivelled, leaving the flexible, toothless 
face without any support. By stages which we cannot 
discover, because they concern only soft parts which are 
never fossilised, tliis flexible face became the wonderful 
prehensile proboscis of the elephants as we laiow them 
to-day. 



The Latest Discovery 
Concerning CoLrvcer. 

By J. T. Cunningham, M.A., F.Z.S. 



Whenever a startling discovery is made in science the 
hope immediately arises that it may be applied to the 
cure of the most dreaded of human diseases. X-rays 
have been tried, and now physicians and patients are in 
despair because radium cannot be obtained with sufficient 
facility. But even if radio-activity is found to be capable 
of checking the malignant progress of cancerous growths, 
it is not likely to be more than a refined method of 
cauterisation, a merciful substitute for the surgeon's 
knife. No radical improvement in the treatment of the 
disease is probable until we know more of its nature and 
causes ; still less is it possible without such knowledge to 
devise methods of prevention. The brilliant discoveries 
of recent years have shown that many of the most 
dangerous diseases are caused by infection, by the intro- 
duction into the human body of infinitesimal organisms 
of an animal or vegetable nature. Typhoid and tuber- 
culosis, for example, are due to vegetable germs, malaria 
to minute acti\e organisms belonging to the animal 
kingdom, and in the latter case the disease is only com- 
municated by means of inoculation carried out by mos- 
quitoes. 

Numerous attempts have been made to prove that 
cancer is also a germ disease, but the latest researches 
tend to show that this view is erroneous. There is a 
certain amount of evidence that cancer may be to a 
certain degree infectious, but nothing to prove that the 
contagion is caused by the transmission of a living germ 
as in typhoid fever or malaria. The peculiarity of cancer 
among diseases is that it consists in the rebellion and 
malignant behaviour of certain parts of the body itself, 
not in the attacks of foreign enemies. Cancer in fact is 
a state of civil war in the body, a reign of terror pro- 
duced by outbreaks of murderous fury on the part of 
licentious revolutionists at one or more localities. 

The body is a complicated organisation of which the 
ultimate units are microscopic cells, each cell being a 
speck of living substance containing a central denser 
particle called the nucleus. The cells are of different 
shapes and sizes, and are united in various layers and 
masses which constitute the tissues, such as the muscular 
tissue, the bones, the brain and nerves, &c. Growth is 
due to cell-division, one cell dividing into two, and each 
of these two growing till it is again as large as the mother- 
cell, from which it was produced. The fertilised egg from 
which the body of any animal is developed is a single 
cell, and the de\'elopment commences by the division of 
this cell into two, which divide into four and so on. 

In this process of cell-division is manifested to the 
microscopist a regular series of changes in the nucleus. 
In its resting state the nucleus is a spherical structure 
containing a network of delicate threads. In division 
the spherical outline disappears and the network acquires 
the form of a convoluted continuous thread. This thread 
divides into a number of separate V-shaped loops, which 
are arranged on the finer lines of a spindle-shaped figure. 
Each loop divides along its length into two loops, and 
one half of each loop passes to one end of the spindle, 
the other to the other. This is the central event in cell- 
division, by which one group of nuclear loops forms two 
groups, and each of the latter forms a daughter-nucleus. 

Now it is a curious fact that the number of these 
nuclear threads which appear at each cell-division is 



Feb., 1904.] 



KNOWLEDGE & vSCIENTIEIC N1«:WS. 



15 



constant in the same species of animal throuf:;hout life. 
The number may be 8, or 12, or 20, or 40, or some other 
number, but in the human body or that of any other 
animal the number is the same in each cell-di\ision. To 
this statement, however, there is an exception. In the 
divisions which lead to the formation of reproductive 
cells, eggs or sperms, only half the usual number of 
loops is formed, and the division of these cells is of a 
peculiar type. The V-shaped chromosomes are replaced 
by loops and bends and rings, and these, also, range tlicm- 
selves in a different way. This is one of the most curious 
facts in microscopical science. Fertilisation consists in the 
complete union of the nuclei of two reproductive cells, 
and if the same number of nuclear loops were always 
formed, this number would be doubled in each genera- 
tion, so that if we began with two we should go on to an 
infinite number. But as each reproducti\e cell has only 
half the proper number, the fertilised egg formed of two 
cells again has the proper number for the species. 

Professor Farmer, of the Royal College of Science, 
with his colleagues, Mr. J. E. S. Moore and Mr. C. E. 




Fig. I. — Diagram of a somatic 
division showing the split 
chromosomes, the halves of 
which form the daughter 
nuclei. The full number of 
the chromosomes is not shown. 



, 2 — Diafirain of a hctcrotypc 
divisiotl showiiif,' the character- 
istic rings and loops which split 
transversely to form the da^igli- 
ter elements. As in the pre- 
ceding figure, the full nund)erof 
chromosomes is not shown. 



fReproduced, by permis .ion, from The Hriti^h Mcdual Jou))utI\. 

Walker, has made the remarkable discovery, which has 
just been communicated to the Koyal and the Linnajan 
Societies, that these peculiarities in the division of repro- 
ductive cells occur also in cancer cells. The cancer 
is a mass of cells in a state of furious growth, and it 
invades and destroys the natural tissues all around it. 
The cells of the cancer show all stages of cell-division, 
and Professor Farmer finds in these stages the peculiari- 
ties which properly belong to reproductive cells only. 
In particular the number of nuclear loops is only half 
the number present in the cell-divisions of healthy tissue. 
Professor Farmer is a botanist, and is distinguished for 
his researches in the microscopic structure of the cells of 
plants. It is a remarkable fact that in the processes of 
cell-division, reproduction, and fertilisation, the trans- 
formations seen in plant cells are essentially the same 
as in animal cells. The formation of the pollen of a 
flower in the stamens affords an example of the reduction 
of the number of the nuclear loops above mentioned to 
half the number proper for the plant. Only after the 
pollen nucleus has united with another in fertilisation is 
the full number regained. Again, a fern produces not 
seeds but spores. The nucleus of one of these spores 



contains only half the proper number of nuclt/ar loops, 
and the divisions of the space which form the green Hat 
growth preceding the development of the fern present 
the peculiarities which have now been observed in cancer. 
The theory suggested, therefore, is that cancer is llu^ 
abnormal formation of rejiroductive tissue in parts of the 
body where no such tissue should be, or in certain cases 
the abnormal behaviour of reprtxluctive cells in their 
natural position : the peculiarities of such cells being 
associated with a tendency to rapid division. 

The theory, if true, does not completely soKe the 
problem. The (|uestion still remains, What are the 
causes of this outbreak of peculiar activity in the cells; 
how can we prevent it and guard against it ? The most 
plausible suggestion at present is that some chemical 
compounds are protluced in the body which stimulate 
and excite the cells to this insane and destructive fury, 
and we still have to discover whether this is true, and 
whether the stiniulalion can he prevented or stopped. It 
is something, however, to ha\e more light on tlie nature 
of the disease, to be investigating in the right direction. 
Something is already known of the stimulation of cells to 
division by means of reagents, and it ought to be possible 
to discover some antidote to the tendency to division. 
Surgery is our only remedy at present, and is sometimes 
very successful ; but there is always the possibility that 
the unknown causes may continue at work, and develop 
new centres of cancerous activity. 

Zoological Notes. 

liy R. LVDEKKEK. 

Similarities of Elephants and Dugongs. 

.\t the conclusion of his memoir on the evolution of 
the I'roboscidea, recently published in the I'kilusophual 
Transactions, Dr. C. W . Andrews directs attention to 
certain very remarkable resemblances existing between 
the elephants and their extinct allies (I'roboscidea) on 
the one hand, and the manati and dugong (Sirenia) on 
the other. Among the features common to the two groups 
are the non-deciduate and zonary placenta, the ab- 
dominal testes, the pectoral position of the mamma-, the 
bilid apex of the heart, the general absence of a foramen 
in the lower end of the humerus, and a remarkable 
similarity not only in the form of the molars, but likewise 
in the mode of successitjn of these teeth, which are pushed 
forward in the jaws with advancing age. Whereas, how- 
ever, in the Sirenia this pushing forward is due to the 
development of additional teeth at the back of the series, 
in the Proboscidea it is caused by a progressive increase 
in the size of the individual teeth from front to back. In 
both cases the anterior molars are shed as they become 
worn out. Other resemblances between the two groups 
exist. .'Mtliough the evidence is far from being con- 
clusive, yet it is strongly in favour of a relationship 
between sirenians and proboscideans, albeit at a very re. 
mote epoch. * :■ 

Fos.sil Reptiles. 
In a recent issue of the Pliilusuphical 'I'l-ansailiom, Mr. 
G. A. l^oulenger describes some interesting reptilian 
remains from the Triassic sandstone of Lossiemouth, 
near El^in. They include a remarkably fine skull of 
Ilypcrudapcdou, which shows the structure of the palate 
better than in any other known specimen. The main 
difference from the corresponding aspect of the skull of 
the existing tuatera {Sphcnodon) of New Zealand, apart 



i6 



KNOWLEDGE .^ SCIENTIFIC NEWS. 



[Feb., 1904. 



from the dentition, is to be found in the smaller bony 
roof of the mouth, and the narrower \omers. Another 
skull, which is made the type of a new genus and species, 
under the name of Stowmctopon iaylori, comes still nearer 
to the tuatera. Other specimens show that the reptile 
previously described as Oniithositchus is not, as originally 
supposed, a dinosaur, but is more nearly related to Phyto- 
saiinis {Belodon), which latter Mr. Boulenger, like the 
author of the under-mentioned memoir, thinks should be 
removed from the Crocodilia to an order apart. 
* * * 

Classification of Reptiles. 

An extremely important memoir on the classification 
of reptiles is published by Professor H. F. Osborn, in the 
Memoirs of the American Museum. Following the lead 
of certain other writers, the author proposes to divide 
reptiles into two main stems — Synapsida and Diapsida ; 
the former including the primitive Cotylosauria, the 
mammal-like Anomodontia (exclusive of the American 
Pelycosauria), Chelonia (tortoises and turtles), and 
Sauropterygia (plesiosaurs), and the latter all the other 
groups. The one branch, it is urged, gave rise to 
mammals, and the other to birds. The main line of 
cleavage between the two branches is the single, or 
undivided, temporal arch (and the consequent presence 
of only one temporal vacuity) in the former, and the 
duplication of the same arch in the latter. 

The divergence from the classification usually adopted 
in this country is not very great, if one factor be borne 
in mind. European writers usually classify animals 
according to their degree of evolution, while American 
naturalists prefer a phylogenetic scheme. That is to 
say, the former draw their lines of division horizontally, 
and the latter vertically. A case in point is afforded by 
the ancestry of the horse, treated in our last issue. 
American writers would include in the Eqitida all the 
members of the series down to and inclusive of Hyra- 
cothcrium, w-hereas English naturalists place in that 
family only the really horse-like latter forms, while they 
would refer the earlier types to other families, among 
which would be embraced the ancestors of the tapirs 
and certain " non-adaptive " forms. Much may be said 
in favour of both schemes ; which, instead of being op- 
posed to one another, are in reality different aspects of 
the same view. 

Duration of Pregnancy in the Badger. 

It is not a little remarkable that there should still be great 
doubt in regard to such an apparently simple matter as 
the duration of pregnancy in the badger. A. writer in 
the December number of the Zoologist considers that the 
period is about 12 months, whereas another observer had 
some time ago put it at about 4^ months. Perhaps the 
true explanation may be that suggested in Sir H. John- 
ston's " British Mammals," namely, that the normal 
period is about six months, but that, as in the roe-deer, 
under certain circumstances, development may be so 
retarded as to make the time of gestation double that 
length. , -<■ * 

Evolution of Marsupials. 

An important memoir by Dr. B. A. Bensley, on the 
evolution of Australian marsupials, has just been pub- 
lished in the Transactions of the Linnaan Society. In 
regard to the origin of marsupials generally, the author 
is of opinion that the vestigiary placenter of the 
vansicoots has been independently acquired, and is not 
therefore indicative of descent from placentals. Never- 
theless, he admits the comparatively near relationship of 
placentals and marsupials. The latter are believed to 
have been primarily differentiated by the assumption of 



arboreal habits, and the earliest forms that can be defi- 
nitely assigned to the group are the opossums, which 
thus form the stock of all the modern types, with the 
possible exception of the Tasmanian wolf, or thylacine. 
This arboreal radiation distinguishes marsupials from 
the extinct creodonts, which were terrestrial. At the 
same time, the thylacine, which it is suggested may have 
been a foreign immigrant into Australia, appears to bfe 
related to certain middle tertiary South American types 
(sparasrodonts), which may themselves be connected with 
the creodonts. How this fits in with the arboreal 
ancestry of the other marsupials is left unexplained. 

That curious creature, the gigantic extinct Thylacoles 
of Australia, originally regarded by Owen as carnivorous, 
but considered by Flower as herbivorous, is reaffirmed 
to be a flesh -eater. 

As regards the date when marsupials first reached 
Australia, there has been much difference of opinion, 
Wallace giving it as Jurassic, Spencer as Cretaceous, 
and Lydekker as Eocene ; the author considers that it 
did not take place till Miocene times. Whether the 
route traversed was via the !Malay .\rchipelago and 
Papua, or by Antartica, is left undecided. There are 
many other points of interest in the memoir, to which 
lack of space forbids allusion. 

Death of Prof. Karl von Zittel. 

Palaeontologists throughout the world will hear with 
deep regret of the death of Professor Karl von Zittel, 
which took place at ^Munich from heart-affection. Pro- 
fessor Zittel is most widely known by his splendid 
Manual of Palaontology, of which a smaller edition was 
published as a Handbook. The latter has been trans- 
lated into French, and two volumes of an English 
(somewhat modified and expanded) edition have also 
appeared. Much original palaeontological work was 
also accomplished by the late Professor. 

The Electric Eye, 

Curious Experiments with Electric Sparks. 

Mr. Walter J. Turney describes in the Scientific 
American Supplement some very interesting experiments 
showing results which he attributes to the ultra-violet 
rays of light. An ordinary half-inch Ruhmkorff coil has 
the knobs of its terminals so adjusted that sparking just 
fails to take place across the gap. On presenting a con- 
ductor to the inner side of either knob, vigorous sparking 
at once takes place and continues so long as the conductor 
remains, ceasing as soon as it is removed. If, however, a 
non-conductor be presented in the same way, a precise 
result, oddly enough, ensues. A piece of bare wire, W, 
about four inches long, was next attached to one of the 
knobs, and bent round as shown in the figure. If the 
conductor C be presented to the end, T, of the wire, con- 
tinuous sparking will occur at the gap G. On now 
placing a screen, P, of cardboard, glass, or metal, so that 
G is invisible from T, sparking will cease, but will 
recommence so soon as the screen is removed. If, how- 
ever, the screen be of rock-crystal, gypsum, rock-salt, or 
alum, the sparking will not be interrupted thereby. 
In another arrangement tried, a mirror was introduced 
to reflect the image of the junction on to the spark gap, 
with similar results, as though the spark could see what 
was going on. 

A further modification was the introduction of a square 



Feb., 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



17 



prism of rock salt, about three-quarters of an inch wide, 
as a screen. l-"irst this was turned so that one face was 
perpendicular to the line joining T to G. On placing 
the conductor near to T, vigorous sparking coniiiicnced 
at G. If the prism be then turned so as to present an 
angle, the vigour of the sparking will be diminished, even 
though the prism be moved slightly to one side so that 
the line joining the points would only traverse a small 
thickness of the rock-salt. The exact explanation of 
these phenomena is not clear. It seems evident that 




light, which can be impeded, reflected, or refracted, is the 
origin of the effects shown. That they are not caused by 
ordinary light, however, seems to be the case, since the 
plates (three-quarters of an inch thick) of rock-crystal, 
&c., interrupt the communication. The author concludes 
that rays of ultra-violet light are the cause of the 
phenomena. This seems a promising field for investiga- 
tion, as the apparatus is so very simple and easily 
applied. 

The Altimeter. 

We have received from Messrs. Newton and Co. a list of 
their optical and other scientific instruments. .Among their 
novelties is the .Altimeter, which has Ijeen made to supply a 
want that has been felt anions kite t1 vers and military balloonists. 
It is a simple form of aneroid barometer marked in figures for 
heights, and is so devised that the hand on the dial rests at the 
highest altitude obtained by the kite or other aeronautical 
machine on which it has been sent up. The scale tends to 
five thousand feet, and the full-sized instrument in an alumi- 
nium case weighs about seven ounces. .Messrs. Xewton 
mindful of the increasing price of radium, which makes even a 
few milligrammes of the metal an expensive luxury, have pro- 
duced a radium screen, which is a sheet of glass coated with 
a mixture containing radium bromide in very small quantities. 
The largest sized screens cost half a guinea, and there are 
cheaper ones which are sufficient for showing many of the 
remarkable properties of the metal. 



It is not to northern China that one would usually look for 
an example of electrical progress, but there is at least one 
place on the eastern shore of the Liaotung Peninsula which 
might well set an example to many of the western towns. We 
refer to the city of Dalny, which lies near Fort Arthur, in that 
portion of the Chinese Empire which was leased to Kussi.a in 
189S. Electrically, Dalny is up-to-date. It has both tele- 
phones and the electric light. The central station, which is 
considered the finest electric plant in Asia east of Singapore, 
was finished over a year ago. It is eijuipped with three of 
Ganz and Co.'s generators, with a total of looo-horse power, 
and has a reserve space for additional machines to double its 
present capacity when required. Dalny, besides other things, 
is an important seaport, and has a dry dock 380 feet long, 
50 feet wide, and iS feet deep, which is equipped throughout 
with electric pumps. A larger dry dock is building, at which 
electricity will also be adopted. In connection with the dry 
dock are the harbour repair shops, with foundry, smithy, 
machine and fitting shop, boiler shop, etc. All these shops 
are electrically driven and lighted throughout. Dalny also 
boasts an excellent telephone service, and altogether it may 
fairlv claim to be one of the most progressive cities in the 
East. 



Continental Physical 
Notes. 

By Dr. .\i,fkI':i) Grahenwit/. 



Resea.rches irv Sola.r and Stella^r 
Photometry. 

The accurate data we possess as to the r.itio between the 
intensity of the dilTereut stars are due to the work of several 
generations of astronomers. As regards, however, the ratio 
between the intensity of the sun and that of the stars, the 
results are far from being as satisfactory, the figures stated by 
different observers varying up to ratios as high as i and 10. 

The knowledge of these ratios, as pointed out by Ch. I'"abry 
(Eclair. Klec. No. 50), is, however, of the highest interest, 
allowing as it would of determining for stars the distance of 
which from the earth is given the ratio between their absolute 
candle power and that of the sun. and thus of classifying the 
sun, so to say, in the hierarchy of the stars. 

.As the light of the sun has a colour resembling closely that 
of most of the stars, a photometric standard of the same shade 
could be chosen, which is far from being the case in connec- 
tion with our ordinary lamps. To this effect, l<"al)ry projected 
the light of a glow lamp through a layer of an ammoniacal 
solution of copper sulphate; l)y regulating either the thick- 
ness or the concentration of the li<|uid layer, the emerging 
light could be given a tint strictly identical with that of the 
light of the sun. The photometric standard thus modified 
would be compared separately, both with the light of the sun 

and that of a star when the ratio " was found to be about 

\V ega 
6 X io"\ 

As regards the data relative to the illumination produced 
by stars in terms of our photometric standards, the results 
obtained are true only to within 10 per cent., on account of 
the difficulty inherent in the dift'erence of coloration. Accord- 
ing to Fabry, the illumination produced by the sun when in 
the zenith on the level of the sea is about lao'ooo lux, being, 
as a matter of course, variable with atmospheric conditions, 
but to a smaller extent than might be anticipated, provided 
that only days of fine weather be considered. Photometric 
measurements will allow of ascertaining whether the sun is a 
variable star. 

These researches will enable the photometric unit of astro- 
nomy to be connected to that of physicists. The intensity of 
a star should be measured by the illumination produced on a 
surface perpendicular to its rays, being expressed in lux. On 
the other hand, astronomers will define the same by its nuif^ni- 
tudc, the magnitudes of two stars differing by one unit, as the 
ratio of their intensities is 2 : 3, the most brilliant h.iving the 
smaller magnitude. The following table records some com- 
parative data of this kind : — 



St.ir. 


Maenitudr. 


Illumination in I.ux 


Sun . . 


.. - 20-6 . 


. I2O'0O0 


Moon 


.. - I3'2 . 


0'2 


Star first maKnitude 


.. + I 


I '05 X 10-" 


Star sixth maHnitudi.- 


.. + 5 


97 X 10-'' 


Star fourteenth magnitude 


.. -+- 14 


(j& X 10 -12 



As the most feeble stars visible to the naked eye are these 
of the sixth magnitude, one candle ceases to be visible to the 
naked eye at a distance of about 10 km., and a telescope 
showing stars of the fourteenth magnitude would .allow of 
seeing a candle at a distance of 400 km. (apart from atmo- 
spheric absorption). 

Electric DischaLrges in the Air. 

In a paper read before the .Angers Congress of the; I'Yench 
.Association for the .Advancement of Sciences, Proicssor de 
Kowalski describes some experiments made by him, in con- 
junction with Mr. Mosciki, on the chemical action of high 
frequency electric discharges in gaseous mixture. With a 
certain frequency, a discharge through a gaseous medium is 
found to take a special character, which, by the way, depends 
also on the amount of electric energy available. The chemical 
actions of a similar discharge are very important from the 



i8 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



point of view of practical application, as in air an abundant 
production of nitrous vapors is observed ; whereas in mixtures 
of carbonic gas and nitrogen both nitrous vapours and carbon 
monoxide are produced ; with a mixture of l)enzine and nitrogen 
vapours, cyanogen and hydrogen will be obtained. On account 
of the importance of the problem in practice. Kowalski and 
Mosciki have especially dealt with the production of nitric 
vapours and hence nitric acid. They were able to obtain up to 
44 grams of nitric acid per kw. hour, it appearing from their 
calculations that the price of one kg. of calcium nitrate would 
not be upwards of I'jd. 

De Kowalslii next describes some experiments made on 
electric discharges on the surface of insulating bodies. As one 
side of the insulating plate is covered with a conductive layer 
while discharges are being produced on the other, sparks very 
much longer than without a conductive layer are obtained. 
Photographs presented by the author show the sparks to 
follow accurately the way drawn by conductive laver on the 
side of the plate opposite to the discharge, it being thus pos- 
sible to obtain sparks of a triangular, square, zigzag, &c., 
shape. The author finally points out the analogies shown by 
the discharges with those produced in the atmosphere during 
thunderstorms. 

On some Novel Phenomena in connec- 
tion with N-Rays. 

Professor Blondlot actively continues his investigations of 
N-rays. and in a paper recently read before the French 
Academy of Sciences we note some interesting facts. The 
author has some time ago observed that sources of light would, 
under the action of N-rays, show an increase in brilliancy. 
Xow Blondlot thought it interesting to test whether the same 
phenomenon takes place in the case of a body reflecting the 
light from an external source being employed instead of an 
illuminant proper. The following experiment was accordingly 
made: A ribbon of white paper, 15 mm. in length and z miri. 
in breadth, was fixed vertically to an iron wire support ; the 
room being darkened, the paper ribbon would be feebly illumi- 
nated by projecting on the same, laterally, a beam 'of light 
given off from a small plane enclosed in a box where a vertical 
slit was provided. The X-rays from an Auer burner, traversing 
a rectangular slit in front of the above slit, would strike the 
paper ribbon. Xow, if the rays were intercepted bv inter- 
posing either the hand or a 'lead plate, the small paper 
rectangle would be darkened and its outline lose in distinct- 
ness; as soon as the screen was taken away again both the 
brilliancy and distinctness would reappear, this giving evidence 
of the light diffused by the paper ribbon being increased under 
the action of X-rays. 

Xow. the difiusion of light is a complex phenomenon, where 
regular reflection plays the part of an elementarv fact. The 
author therefore thought of investigating whether the reflection 
of light is also modified under the action of X-rays. To this 
effect, a polished knitting needle of steel was placed vertically 
in the position formerly occupied by the paper ribbon ; in a 
box completely closed but for a vertical slit at the height of an 
.Auer lamp (shut by a screen of transparent paper), a flame was 
placed so as to illuminate the slit. When adjusting conve- 
niently the eye in the slit, the image of the latter formed bv 
reflection on thi steel cylinder was distinctly seen ; while the 
reflecting surface .as struck by X-rays, when the action of 
the ray proved to strengthen the image. Similar results were 
obtained, replacing the needle either by a plain bronze mirror 
or a polished quartz surface. All these actions of X-rays 
retjuire an appreciable time both to be produced and to dis- 
appear. On the other hand, no action of X-rays on refracted 
light could be observed, though various experiments in this 
direction were undertaken under many diff'erent conditions. 

As the capacity of seizing small \ariations in candle power 
is rather different for different persons, these phenomena are 
nearly at the limit of perceptibilitv to some persons, who. only 
after a certain practice, will be able to seize them regularly 
and to observe them safely, whereas others will at once, and 
without the least difticulty, note the strengthening effect of N- 
rays on the candle power of a small illuminant. Xow, as the 
author has recently observed the same phenomena, with con- 
siderably increased intensity, when replacing the- .Auer burner 
by a Xcrnst lamp, the.se phenomena may now be produced 
with such intensity as to be visible to anybody. 



The Printing Telegraph 

The Berlin Teletyping Central Station. 



Telephones, rendering only words as they are spoken, 
are frequently insufficient for business purposes ; in ad- 
dition to a correct transmission of a communication, 
there will in many cases be necessary an acknowledgment 
in writing of this transmission. On the other hand, 
there is the liability of telephonic conversation to be 
overheard by a third person, and finally the person rung 
up on the telephone may happen to be absent, when his 
return will have to be waited for, and much time be lost. 
In order to afiord an efficient means of communication in 
all these and many other cases, a new public printing tele- 
graph service was installed in Berlin on Oct. ist, when 
the " Ferndrucker Centrale " was opened to public service. 

The telegraph, as constructed by the Siemens and 
Halske Company, is a type-printing telegraph similar to 
the well-known Hughes type printer and the Baudot 
telegraph. The main distinctive feature from former 
apparatus is, however, the fact that the latter moving 
freely, the simultaneous working of the instruments 
established on the same line had to be obtained by the 
skill of the operator, whereas the operation of the new 
apparatus is as simple as that of an ordinary typewriter. 
The apparatus, in fact, is nothing else than a teletype- 
writer, any letters, figures, or signs of punctuation being 
printed by pressing down a key corresponding with the 
signal in question. There are two circles of signs on the 
periphery of the type wheel, one comprising the letters 
and the other the figures and signs of punctuation. A 
.<^hift key serves to adjust the type-wheel either for letters 
or figures. Both sets of apparatus, connected by a line, 
may be used either as sender or as receiver, without any 
special preparation being necessary, as soon as a special 
white key is struck ; the apparatus in question is in fact 
made to serve as sender, and all will be ready for use. 
The printing takes place simultaneously in both the 
transmitting and recei\-ing apparatus, no matter whether 
there is or is not somebody operating the receiving ap- 
paratus. In the case of the owner of the apparatus 
being absent, lie will read the telegram printed on the 
paper ribbon on his return. The new telegraph, giving 
two identical records of the same telegram in the sending 
and receiving apparatus respectively, will place at the 
disposal of the transmitter an evidence of the correctness 
of his communication, so as to exclude any possibility of 
misunderstanding. 

The advantages afforded by the printing telegraph, as 
compared both with telephone and present telegraph 
system, will be self-evident. Like the telephone, the 
new telegraph may serve for a direct communication 
between any two persons o\er any distances, but for its 
being free from any possibility of hearing mistakes or 
other misunderstanding, in virtue of the double simul- 
taneous reproduction in printing of each communication. 
At the same time, there is, as above stated, no danger 
of a third person overhearing the communications. This 
is therefore the only means of communication enabling 
despatches to be kept strictly private. 

A central station with arrangements and working 
methods similar to those of central telephone stations has 
been opened in 28, Zimmerstrasse, Berlin, serving in the 
first place to secure mutual communication between all 
the subscribers connected to the Berlin printing telegraph 
net. The central station is fitted with a switchboard 
comprising indicators and cathices for one hundred sub- 



Feb., 1904.] 



KNOWLEDGE cS: SCIENTIFIC NEWS. 



19 



scribers. Sixteen connecting strings allow of 32 subscri- 
bers being simultaneously connected so as to enable a 
simultaneous communication between one third of all the 
subscribers in the case of the switchboard being complete. 
As soon as a subscriber presses down the calling key of 
his printing telegraph, the official in charge of the indi- 
cator board at the central station will be advised by the 
indicator of the subscriber in question dropping and an 
alarum being rung, when he will have to put himself in 
communication with tiie caller, to ask him for the desired 
connection through a special enquiring apparatus, and 
connect both subscribers so that their apparatus are 




ready for immediate mutual communication. There is, 
however, in addition, the possibility of connecting any 
desired number of subscribers to the same printing tele- 
graph so as to transmit the same communication simul- 
taneously to all the subscribers. This is ensured by the 
subscribers who, as a rule, are connected to the indicator 
board of the central station, being disconnected from the 
latter and connected to the transmitting apparatus in 
question by means of a group switch. 

Similar telegraphic ser\ices from one central station to 
a certain number of subscribers simultaneously, by means 
of a so-called ticker, have for some time been used in New 



York, London, and Paris. A similar service has been in 
operation also in l!renierhavcn,(iermany,for transmitting 
ship telegrams from one central station to 100 sub- 
scribers in dilTerent places. It is intended, from' the 
central station just opened in IJcrlin, to transmit simihir 
information to a certain number of subscribers, hmiting 
the service at first to Exchange telegrams, wliich arc 
transmitted at gi\en hours from the transmitting appara- 
tus in tile Berlin ICxchange. The same means of com- 
munication could he employed for transmitting telegrams 
from a central telegraph oflice, such as Renter's, to a 
certain number of newspaper offices. In addition, the 
above central station is intended to secure comnnmication 
of the subscribers with the central Slate telegraph oflice 
for transmitting or receiving telegrams through the State 
telegraph, for which subscribers are charged a rather low- 
extra fee of so much per word. 

The main feature will, liowevcr, be the diycct iiiiitmil 
coiuMitnicatiflu between the subscril)ers, and in tiiis respect 
]->erlin may boast of having quite a unicjue means of 
communication. The system has, by the way, neen in 
operation for some time with great industrial concerns 
such as the bierlin Aligemeine l'"leklricitats desellschaft 
and the Siemens and Halskc Company for communica- 
tion between their \-arious business departments. 




In addition to the type-printing telegraph used in con- 
nection with the teletyping service described in another 
note, the Siemens and 1 lalske Company have just brought 
out another kind of printing telegraph, intended for rapid 
service. The apparatus is analogous to the so-called 
automatical telegraph, where an apparatus similar to a 
typewriter pierces for each letter to lie telegraphed cer- 
tain holes in a continuous paper ribbon. The latter, on 
being drawn along through the rotating telegraphic 
sender, will throw automatically corresponding currents 
into the line. As the Siemens apparatus is capable of 
telegraphing 2,000 letters per minute, the telegrams trans- 
mitted by a large number of officials will be sent on the 
same wire. Two holes are pierced for each letter, the 
letter itself being printed immediately above in plain 
ordinary printing characters. The perforating may even 
be effected by the public itself. A disc, where the \'arious 
letters are cut out as in a pattern, rotates at a speed of 
2,000 revolutions per minute, between a spark gap and a 
continuous ribbon of photographic paper. Whenever a 
spark passes in the gap, a silhouette of tiie letter happen- 
ing to be in front of the gap will be projected on the paper 
ribbon, which on running through sponges impregnated 
with developing and fixing liquids, will complete the 
photographic process. 



20 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



The Face of the Sky for 
Febrviary. 

I>y \V. Shacki.eton, F.R.A.S. 



The Sun. — On the ist the sun rises at 7.43, and sets 
at 4.45 : on the 29th he rises at 6.50, and sets at 5.36. 
The sun is after the clock, the equation of time reaching 
a maximum of 14 m. 25 s. on the 12th. 

Sun spots may frequently be observed ; of late, the 
solar disc has rarely been devoid of spots. For deter- 
mining spot positions the appended table should prove 
useful 



Date. 



Axis inclined to W. from 
N. point. 



Centre of disc, S of 
Sun's equator. 



I- 


eb 


5 •- 


13° 


38' 


6° 


21' 




,, 


15 •• 


17° 


20' 


6° 


52' 




■• 


25 ■■ 


20- 


28' 


7 


10' 



The Moon : — 








Phases. 


H 


M. 


Feb. I .. 
., 8 .. 
,, i5 .. 
., 24 .. 


Full Moon 
; Last Quarter 
• New Moon 
j) First Quarter 


4 

9 

II 

II 


33 P-m- 
56 a.m. 

5 a.m. 

9 a.m. 



The Moon is in perigee and apogee at midnight on the 
1st and 15th respectively. Occultations. — It will be seen 
from the particulars below that there is the interesting 
phenomenon of an occultation of the ist magnitude star 
Aldebaran, and, morevover, the circumstances are most 
favourable as the moon is near the meridian. 




Feb. 24 .\ldebaran ' i' 
,, 29 lO Leonis 3-; 



D. H. 

5.57 p.m. 7.15 p.m. 8 7 6.17p.m. 
8.53 p.m. g. 46 p.m. 13 10 .it 6 p.m. 




The Planets. — Mercury is a morning star in Sagit- 
tarius; on the ioth,when he is at greatest westerly elon- 
gation, he rises i hr. 10 min. in advance of the sun. 

\'enus is a morning star, rising throughout the month 
about 5.40 a.m. ; she continues to diminish in brightness 
and is becoming more gibbous, about o-So of the disc 
being illuminated. 

Mars continues to be feebly visible in the south-west 
shortly after sunset ; throughout the month he sets about 
7.30 p.m. 

Jupiter is rapidly getting more to the west and also 
diminishing in brightness; on the first he sets at 7.27 p.m., 
and on the 2Qth at 7.40 p.m. About the middle of the 
month his polar and equatorial diameters are 32"-4 and 
34"-6 respectively. 

The configurations of the satellites as seen in an 
inverting telescope, and observing at 6.30 p.m., are as 
follows : — 



Day. 


West. ' East. 


Day. 


West. 


East. 


I 


1034 


16 


24O13 


2 


2O134 


17 


i043« 


1 


0234« 


18 


0324 


4 


1O324 


19 


32O14 


5 


32O14 


20 


321O4 


6 


31O24 


21 


3O124 


7 


3O1* 


22 


13O24 


8 


1023 


33 


2O134 


9 


42C13 


24 


12O43 


10 


4023« 


25 


4O1S 


II 


41O32 


26 


432 o« 


12 


432 1 


27 


4321O 


13 


4321 


28 


43O5 


14 


43O12 


29 


413O2 


15 


4i02« 







The circle (O) represents Jupiter ; G signifies that the satellite 
is on the disc : 9 signifies that the satellite is behind the disc, or 
in the shadow. The numbers are the numbers of the satellites. 

Saturn is in conjunction with the sun on the ist, and 
therefore unobservable. 

Uranus rises only a short time before sunrise; this, 
together with his extreme southerly declination, makes 
him most unsuitable for observation. 

Neptune souths at g.30 p.m. on the ist, and at 7.30 
p.m. on the 29th. He is about half a degree S.E. of 
M Geminorum and his path is shown in the chart given in 
the January number. 

Meteor Showers : — 



D'BJram Illustrating Occultation ol Aldebaran. 





Radiant. 




Date. 


R A. 


Dec 


Near to. 


Characteristics. 


Feb. 5-10 

.. 15 
20 


75' 
236 
iSl" 


+ 41" 
4- 11" 

+ 34" 


7;.'\urigae 
a Serpentis 
Cor Caroli 


Slow; bright. 

Swift ; streaks. 
Swift ; bright. 



The Stars. — The positions of the principal constella- 
tions near the middle of the month at 9 p.m. are as 
follows : — 

Zexith . .\uriga. 

South . Orion, Gemini, Procyon, Sin'ns, Cetus, 

Pleiades, Taurus to the S.W., Cancer and Hydra 

to the S.E. 
West . Andromeda, .\ries, Pisces, with Pegasus 

and Cygnus to the N.W. 
East . Leo, \'irgo. 

North . Ursa Minor, Draco, Cepheus, UrsaMajor 

to the right of Polaris, 



Feb., 1904.] 



KXOWI.I'IK;]' \- SCIHNTIl-lC XI'.WS. 



21 



Minima of Al^ol may be ohserveil 011 tlio isl at 
11.52 p.m.. 4tli at 8.41 p.m., jtli at 5.30 p.m., jjiid at 
1.35 a.m., 24th at 10.24 P-m-. and tlie 2jlh at 7.13 p.m. 

Telescopic Objects: — 

Clusters.- -M35, situated about 2 K.K. of >; Gemi- 
norum or about midway between t Tauri and < Geini- 
norum. Fairlycompacl, presenting a beautiful appearance 
of star streams when observed under favourable con- 
ditions. R..\. \1.^ 3™ Dec. N. 24' 21' N41, about 4" 
directly south of Sirius; \isible to naked eye; Messier 
resjistered this group as "a mass of small stars," K.A. 
\'I.'' 43"> Dec. S. 20^ 38' M44, the Pra-sepe in Cancer, 
visible to the naked eye as a nebulous patch, best seen 
and easily resolvable with a pair of opera or field glasses. 
On account of the scattered nature of the group the 
cluster eflPect is lost when observed through a telescope 
unless very low powers be employed. Situated a little to 
the west and about midway of the line joining <• and 5 
Cancri. R..\. \'I11.'' 34" Dec. N. 20^ 20'. 

Double Stars. — Castor, separation 5"-8, mags. 2-7, 3-7. 
E.xcellent object for small telescopes. The brigiitest pair 
to be observed in this country ; can always be relied upon 
as a good show object. 

»■ Geminorum, separation6"-3, mags. 4, 8*5; very pretty 
double. 

i Cancri, separation i"-i, 5"-3, mags. 5-0, 5-7, 5-5; with 
small telescopes the wider component is readily seen. 

7 Draconis, separation 6i"-j, mags. 4-6, 4-6 ; a pretty 
and easy double, can be separated by observing with a 
pair of opera glasses. 

The Showerof November Leonids in 1903. 



To THE Editors of '■ Knowledge." 
Gentlemen, — .'\t the end of my paper under this heading, 
published in the J.anuary number of " Knowledge," I referred 
to a second magnitude meteor seen at 15 hrs. 59 mins. on 
November 15, and moving in a long and slowly traversed 
path from a probable radiant at 113 —34 . Two of the 
obser\ations from which the real course was deduced were. 
however, somewhat imperfect and indefinite. Fortunate!)' I 
have since received a description of the object as seen at 
Greenwich at 15 hrs. 59 mins. jH sees., and I h.ive recom- 
puted the hei.ghts and radiant. The latter position was 
really in Hydra at about 147 -ii^ and the height of the 
meteor varied from gi to 45 miles during its extended flight 
of 128 miles, which it pursued at the rate of 29 miles per 
second. The object certainly travelled at a much slower 
speed than is consistent w ith a parabolic orbit. 

Professor Herschel has recently been comparing the re- 
corded paths observed on the night of November 15 by several 
observers, and has foimd a few interesting accordances. 
Two of these were of brilliant Leonids, and the real courses 
which I have calculated for these agree very closely with the 
results previously obtained by Professor Herschel, and are as 
follows : — 

Date and Greenwich mean 1 November 15 November 15 
time of the observations. . ) lO hrs. 45.^ mins. 18 hrs. 7 mins. 



Estimated magnitudes 


■■ 4-^ 


>l — 4 


Radiant point 


■ ■ 151 + 25 


151 -f Zi 


Height at beginning 


77 miles 


81 miles 


Height at ending . . 


■ • 52 .. 


60 ,, 


length of visible path 


■• 30 ,, 


24 .. 


Velocity per second . . 


■ ■ '« ,, 


44 .. 



Observers 



A. S. Herschel, A S. Herschel. 
Slough. Slough. 

\V V D.. A. King, 

Bristol. Sheffield 

I W. F v.. 

Bristol 
Notwithstanding the richness of the Leonid shower in 1903, 
and the large number of observations, comparatively few of 
the same meteors appear to have been seen at two stations. 
Bishopston, Bristol, Yours faithfully, 

January 6, 1904. W. F. Denning. 




Comhuted by F. Siiii.i.ingto.v Sc.\li-:s, imj.m.s. 



Magnification of Objectives and Eyepieces 

I r is scarcely necessary to explain to any worker with 
the microscope that, whereas a simple lens gives a single 
magnification only, the essential principle of the compound 
microscope is that the image formed by the first lens or 
system of lenses, called the objectixe, is itself again 
magnified by a second lens or system of lenses known as 
the eyepiece, or ocular. But, simple as this is in prin- 
ciple, the means by which it is brought about, and the 
various points connected therewith, aie often not fully 
understood by ordinary workers, many of whom are not 
clear as to the exact meaning of such terms as one inch, 
half-inch, lVx., as applied to objectives, or to references 
to angular aperture as compared with numerical aper- 
ture, aplanatic aperture, Ac. 

Briefly, the principle on which olijectives are rated is 
as follows: We have here a Itns, or system of lenses, 
with which we form our first magnified image, and this 
image is formed at a definite distance from tlie back of 
the lens. According to Knghsh standards, this distance 
is 10 inches, which was originally adopted as being the 
the normal visual distance of the human eye. Then it 
follows that the relative size of object and image will 
vary directly as their respective distances from the lens, 
or rather from its centre. Accordingly, if the two dis- 
tances are i inch and 10 inches respectively, the initial 
magnification will be ten times, and here we have our 
I -inch objective. If the distances are 2 inches and 
10 inches, the magnification will be five times, and the 
objective will be known as a 2-inch. If the distances or 
foci are A incli and 10 inches, the magnification will be 
twenty times, and the objective is A inch, whilst a i-i2th 
inch objective magnifies initially 120 times. 

On the Continent, however, the image comes to a focus 
about 6h inches behind the objective, this being the 
Continental tube-length, but the rating seems to gene- 
rally remain the same — the i-inch magnifying 10 
times at 10 inches, the 2-inch 5 times, and so on. 
Thus a Continental i-inch objective used with a 
6i-inch tube should only give an initial magnifica- 
tion at this distance of 6-5 diameters. As a matter 
of fact, however, objectives are nearly always overrated, 
sometimes absurdly so, and therefore a Continental 
I-inch may give an initial magnification exceeding 10, 
even with the short tube. 

Of course the tube-length of a microscope can gene- 
rally be varied, and the result will be in the first place a 
readjustment of focus and a conseijuent variation in the 
magnification. But the second result is that, as objec- 
tives are not meant to be used for uncovered objects, they 
have been carefully " corrected " for a certain definite 
thickness of cover-glass. The Royal Microscopical 
Society has used its powerful influence to bring makers 
into line throughout the world with regard to the stan- 
dardizing of the screw of objectives, the diameters of eye- 
pieces, and the size of sub-stage condensers, and it would 
be a great advantage if it could also standardize the 
thickness of cover-glass to which objectives are corrected. 
Perhaps this may be done some day; in the meantime 



22 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Feb., 1904. 



each maker, whether En,L;lish or foreit^n, is a law unto 
himself, and the list of cover-f^lass corrections is a most 
torniidable one. But it follows that any variation in 
cover-glass thickness from that for which the objective 
was originally corrected necessitates a readjustment 
either of the lenses of the objective, by means of a " cor- 
rection collar," or by adjustment of the length of the 
microscope tube. In the latter case, of course, we have 
at once a variation of initial magnifying power, but the 
converse also applies, i.e., that an arbitrary variation of 
tube-length affects the corrections, and consequently the 
performance of the objective. We can at once see the 
limitations, therefore, of the ordinary suggestions as to 
varying the magnification by drawing out or pushing in 
the draw- tube of the microscope. With low powers of 
small angle the difference in performance is not marked, 
and would e\en need a trained eye to detect it, but it 
becomes more- and more marked with an increase of 
angular aperture, which generally coincides with higher 
powered objectives. Broadly speaking, therefore, we 
must use our objectives with the tube-length for which 
they were originally constructed. 

The part played by the ocular — at least by the Huy- 
ghenian type of ocular which is generally used and with 
which we need only concern oursehes here — is twofold. 
It consists of a field-lens and an eye-lens, with a dia- 
phragm between. The field-lens may really be con- 
sidered almost as part of the objective, for its action is to 
draw in the image rays and bring them to their final focus 
in the plane of the diaphragm just mentioned. Then the 
eye-lens merely magnifies this image and brings it to a 
focus suitable for the eye. 

It is important to note, therefore, that the magnification 
of any unadjustable ocular is always a fixed quantity, but 
that the magnification of an objective (perfection of image 
apart) will vary according to the tube-length. In spite of 
this, many Continental and some English makers persist 
in treating the two magnifications as if it were the ocular 
magnification which varied, thus giving rise to no little 
confusion. I have seen lists in which elaborate tables 
have been made of the combined magnifications of objec- 
tives and oculars used with a 6i inch tube, in which the 
ocular has been treated as the varying quantity, and I 
have seen calculations of magnifications of objectives in 
one and the same table in which an inch or other objec- 
tive is treated as magnifying 10 times and in another 
7 times, at 6i inches distance, the real fact being that the 
oculars are not of the powers they profess to be. All this 
is, of course, very confusing to the beginner. 

Now, focuses do not represent " working distance." 
This merely represents the clear space between the cover- 
glass and the front surface of the objective, and can be 
measured by a carefully made wedge of wood which is 
inserted when the objecti\e is focussed, marked, and then 
measured. 

Nor is it necessary for us to work out with mathemati- 
cal accuracy the exact equivalent foci of objectives, which 
are made up of complicated systems of lenses. This would 
be a difficult matter. It will be sufficient for us to obtain 
the approximate equivalent focus — approximate because 
the centre of the system cannot be readily obtained. If 
we set up conjugate foci at equal distances from the centre 
of the lens, the object and image will l)e of the same size, 
and conversely if the object and the image are the same 
size the distances of the conjugate foci are identical. 
This, of course, means that object and image are both 
beyond the principal focus ; in fact they are at a distance 
just as much again as is the principal focus, i.e. they are 
on each side twice the distance of the principal focus from 
the centre of the lens. Therefore, the equivalent focus 



can be obtained by projecting the image of a brightly 
illuminated object upon a screen at such a distance that 
both image and object are equal, and dividing the total 
distance by four. Having obtained the equivalent focal 
length, we can easily calculate the magnification with any 
tube-length. 

It is, however, with the magnifying power that the 
microscopist generally needs to concern himself, and this 
known, the equivalent focus can be easily obtained. 
Perhaps the easiest method of obtaining this is that 
mentioned in Carpenter. A micrometer slide ruled in 
hundredths and thousandths of an inch, or in tenths 
and hundredths of a millimetre, is placed upon the stage 
of the microscope, and the latter inclined to the hori- 
zontal position. A strong light is transmitted through 
the microscope, and the room darkened. The micro- 
meter lines are then focussed sharply upon a piece of 
white cardboard placed five feet (60 inches) behind the 
front lens of the objective. The divisions on the screen 
are measured with an ordinary foot or millimetre rule 
and the result divided by 6, which gives, of course, their 
size at 10 inches from the objective. The value of the 
original stage micrometer divisions being known defi- 
nitely beforehand it is easy to calculate the resulting 
magnification. Suppose the distance between the micro- 
meter rulings of two i-iooo of an inch to measure ij- 
inches at 5 feet distance with a nominal i inch objective. 
Then at 10 inches distance they would measure -2083 inch, 
which is equivalent to an initial magnification of nearly 
lol times. A millimetre scale or rule can be used on 
the basis of 25-4 millimetres to an inch. Magnifications 
are always expressed in diameters, or linear measure- 
ments, not in areas. A considerable distance such as 
the above is taken so as to reduce the amount of error 
due to the fact that the measurements should really be 
taken from the principal posterior focus of the objective, 
which in a compound system cannot easily be found. 
But by measuring from the front lens as above a very 
small margin of error is left. It is best to take the 
mean of several micrometer divisions as they are not 
quite accurately ruled. 

Combined magnification of objective and eye-piece is 
calculated by a similar method except that there is not 
the same necessity for taking a longer distance, and the 
image of the micrometer must be accurately projected 
exactly 10 inches from the eye-lens of the eye-piece. 
This may be done either direct by means of a photo- 
graphic camera or otherwise, or at right angles by means 
of a Beale's camera lucida, to a piece of paper placed on 
the table, the microscope being raised if necessary to the 
requisite height so as to get the exact distance of loinches 
from the eye-lens. Short-sighted observers may therefore 
need to use spectacles in ordertoseethelinesonthe paper. 

The eye-piece magnification is readily calculated by 
dividing the combined magnification by the initial mag- 
nification of the objective, independently determined. It 
will be noted that the result, as calculated, gives the 
magnification with a lo-inch tube; any other length is 
easily calculated — a 7-inch tube giving an initial magni- 
fication of 7-ioths of the result as above obtained, and 
the eye-piece mat;nification remaining constant for each 
eye-piece. One further explanation is perhaps necessary. 
We have hitherto been dealing with a total magnification 
calculated for a visual distance of 10 inches from the eye- 
lens, this being the normal visual distance, but it is as 
well to bear in mind that in actual practice an abnormal 
eye will form its image nearer or further away, according 
to whether the eye be short or long sighted. This will, 
of course, proportionately affect the magnification of the 
eye-piece, and, in consequence, the magnification of an 



Feb., 1904] . 



KNOWLEDGE & SCIENTIFIC NEWS. 



object as seen through the microscope by such an observer. 
In making calculations connected with focal lengths 

the most useful formula is ' + , = ^ where p and p' 

p p' f 

denote the conjugate foci, and f the principal focus. 
When we know the size of the image and its magnifica- 
tion, and one of the two foci, such as 10 inches, we can 
use the proportion D :</:;/)' ;/', where D is the diameter 
of the image, (/ of the object, and />' the longer of the 
two foci, then, from the equation given above, i.e., 



I 

P 
I 

P^ 



+ 



P" 
D + 



f 



and the ratio 



D 
d 



P' 
P 



we obtain 



f 



, or more simplj' f = p' 



D + d' 



New Spectrometer Ta.ble. 

Messrs. W. G. Pyc and Cd., of Cambritlge, have re- 
cently brought to my notice a new combination spectro- 
meter, the adjustments of which present quite new 
features, and which might, I think, be adapted to certain 
microscopic accessories. All motions and fittings 
are arranged geometrically. The base consists of 
a heavy iron casting on three levelling screws, having 





a true lathe-turned surface, with two annular V-groo\es 
in it, one near the outer edge, the other a few inches from 
the centre. The telescope and collimator are provided 
with tables or carriages consisting of two pieces each, 
the lower part having two steel balls and one levelling 
screw for the feet. The balls work in the larger of the 
two annular grooves mentioned above, and tiie levelling 
screw on the plane surface a few inches from the centre. 




The upper part consists of a cr.idle having two V sup- 
ports in which the telescope or collimator, as the case 
may be, lies evenly, being held in position by a spiral 
spring trap. This cradle being clamped by a thumb- 
screw to the lower part provides the necessary adjust- 
ment for getting the telescope and collimator into hori- 
zontal alignment. The V-fittings admit of almost any 
telescope and collimator being used. The two parts ol 
the carriage are worked up mechanically true, so that 
very little adjustment is needed to set them optically 



true after the base has been levelled, which can be done 
by using a spirit level in the usual manner. 'l"he 
carriage for the telescope is providetl with a vernier, 
whilst the one for the collimator has an index pointer 
only. The prism-plate consists of two parts, the Upper of 
which is capable of adjustment in the horizontal plane 
without alTecting the lower part, which has thrcu; 
spherical ended feet, two resting in the inner V-groove, 
the other working on the plane surface. The simplicity 
of the arrangement, and the easy way in which it can be 
worked up mechanically, combined with its steadiness 
and large bearing surfaces struck me favourably, and as 
the arrangement could easily he adapted to a reading 
telescope, to say nothing of adaptations to a model theo- 
dolite and se-xtant, circular vernier, simple dividing engine, 
iSrc. 1 trust its description will not seem out of place 
here. This instrument, when shown at the Royal Insti- 
tution on .\pril 3rd last, drew, I understand, considerable 
attention. 

Recent Patents. 

• 9.750. Natural history specimens, preserving. ^[AT^.•• 
soviTS, v., Liptoujvar, Hungary. Sept. 9. 
Beetles are preserved in a manner which keeps the joints flexible 
by treatment with a lliiid consisting of specified proportions of 
alcohol, salicylic acid, sal-ammonia, and distilled water, to which 
arsenic or other substances may be added. The quantity of ammonia 
to be added depends on the colour of the beetle to be preserved. 
When thorouglily impregnated, they are placed in a cool closed 
chamber, to dry, the joints being bent from time to time while the 
beetles are being dried. The liquid may also be employed in pre- 
serving diptera, rhynchola, &c 

19,804. Hydrocyanic acid and cyanides. Wolterkck, II. 

C, 3, Edinburgh Mansions, Ilowick Place, Victoria Street, 

London Sept. 10. 

A gaseous mixture of, preferably, equal parts of ammonia, a 

carbon compound, and hydrogen is passed over a suitable catalytic 

agent, such as platinized pumice, strongly heated and coiitaine<l in 

a reaction chamber or series of chambers. The hydrocyanic acid 

may be collected, or it may be absorbed in caustic potash or soda 

to produce a cyanide. The carbon compound may be carbonic 

oxide or acid, or benzene, acetylene, ethyl or methyl alcohol, &c. 

Water gas may be employed for supplying a mixture of carbonic 

oxide and hydrogen. The gases or vapours should be free from 

water. The I'rovisional Specification states that freshly-reduced 

iron may form the catalytic agent. 

19,823. Turbines or impact=wheels. M.»lcArthur, C, 
and Smith, 1'., both of 75, Church Koad, Woolston, near 
Southampton, Hampshire. Sept. 10. 

Relates to impact- 
wheels driven by ex- 
pansible fluid i)res- 
sure, and suitable for 
propelling ships. The 
impact - wheel has 
vanes u sloping in op- 
posite directions alter- 
nately and of a cor- 
rugateil or other 
curv'cd cross-section. 
The fluid pressure is 
admitted twice during 
each revolution by 
means of a three- 
ported tubular valve «, 
which is rocked by an 
eccentric n on the main 
shaft III- The admis- 
sion \-alve is sur- 
rounded by a ported 
sleeve h, which forms 
a reversing- valve, and 
which can be rocked 
by a handle /' to admit 
the fluid to the porty' 
for forward running or 
to the port / for back- 
ward running. Expansion chambers ( are formed in the wall of the 
cylinder x. 




24 



KNOWLEDGE & SCIENTIFIC NEWS. 



Feb., 1904.] 



19,901. Electric recording apparatus. Hulsmeyer, C. 
gS, Bilker Allee, Diisseldorf, Germany. Sept. 11. 




record may be used for reproduction by causing it to 
wise constant beam of light falling on a selenium eel 
reproducing circuit. 

19,999. Secondary batteries. Fiedler, I, , 
Street, Tottenham Court Koad, and Puchmu 
Mornington Crescent, both in London. Sepl 
Relates to the use of zinc as the ne- 



vary an other- 
in an electric 



71, Huntley 
LLKR, c;., 14, 



Relates to apparatus for recording the variations of an electric 
current in the form of a photographic record produced by the 
variations in a beam of light. The particular example shown con- 
sists in imposing sound waves on a microphone n in an electric 
circuit including a constant battery h and magnet coils il. iP. The 
armatures of the magnets are mounted on a spring-controlled 
pivoted mirror c carrying at its centre a mirror /(. A be.am of light 
k is reflected from the mirror on to a travelling pliotograpliic film 
( enclosed in a case having developing and fi.xing apparatus ; 17 is a 
small opening in the case. The beam of light is varied by passing 
through an optical plate / of varying transparency from end to end, 
and is focussed on to the opening ij by one or more prisms or cylin- 
drical lenses v. The light-varying portions of the apparatus are 
adjustably mounted to allow of varying the sensitiveness. The 



gative plate. The battery consists of 
a papier-mache box n containing a 
tightly-fitting zinc box b, which is 
connected with a second zinc box (, 
the two forming one electrode li. 
Upon the insulating-material, such as 
asphalt, which covers the bottom of the 
box /', the lead-peroxide anode 1 stands, 
and forms the other electrode g. The 
electrolyte i consists of a mixture of 
sulphuric acid, mercury sulphate, potas- 
sium ferro-cyanide, and zinc sulphate, 
and this forms a covering of zinc - 
mercury ferro - cyanide upon the zinc 
electrode, and protects it from the sul- 
phuric acid when the accumulator is not 
in use. The electrolyte may be either 
liquid or rendered " dry " by an ab- 
sorbent such as sawdust. The cell is 
closed in with a layer of sawdust /, a 
piece of cardboaid /; soaked in paraffin, 
and a layer of mastic material m, through 
which is an air pipe /. 



FIC I 




LAST YEAR'S WEATHER— FEBRUARY, 1903. 



DISTRIBUTION OF MEAN TEMPERATURE. 



^40 



RAINFALL. 




'? 
L, 







'J—j- ?n il. 



■J 4.0 f 

'^^ '°'0 'bo? 3° 58 0-99 







0\er the country generally the temperature was considerably 
above the average, the excess amounting to more than 4 in 
all districts, exceptinj; the north of Scotland and the south of 
Ireland, to more than 5^ in many parts of northern, eastern, 
and central England, and to as many as 0'-*2 at York. 



Rainfall was very deficient in the eastern, central, and 
southern parts i>f Iinj,;Iand, and also at some stations in the 
south of Ireland. In the western and northern districts .gen = 
crally there was a considerable excess, the amount at many of 
the Scotch stations being more than twice as much as the 
average. 



UDomledge & Selentifie flems 

A MOXllll.N' lOlRXAL C)l- SCIBNCK. 



Vol. I. No. 2. 



[NEW SEKir.s] 



MARCH, 1904. 



r Entered at 
LStationers' Hall. 



si.\i'i:nci;. 



Contents and Notices. See Page VH. 

TKe Arvcestry of the 
CoLmeL 



By R. LVDEKKER. 

Camels — or rather some of their immediate ancestors — 
have been accorded a privilege commonly said to be 
reserved among ourselves for the fair sex ; in other 
words, metaphorically speaking, they have been per- 
mitted to change their minds. l"or there can be little doubt 
that when these animals originally started on the road 
of getting up in the world — that is to say, on a course of 
specialised development — they intended to become good 
and typical ungulates like their distant cousins the true 
ruminants ; and, for a time at least, the ancestral camels 
appear to have had their toes encased in good service- 
able hoofs of horn. For some reason or other, of which 
we are at present quite ignorant, they appear to have 
considered that this plan was a mistake, and they accord- 
ingly struck out a line of their own, and underwent a 
kind of retrv-gade evolution, with the result that in their 
modern descendants their feet, instead of being covered 
with hoofs, are fitted with large spreading and elastic 
cushions, in which the two toes are to a great extent 
buried, bearing small nails on their upper surface only. 
The reason for this remarkable modification is not very 
easy to see. It is true, indeed, that the cushion-like feet 
of the typical camels of the Old World (from which the 
group derives its scientific title of Tylopoda) are admirably 
adapted for walking on the yielding sands of the deserts 
of Central Asia and Africa. But, on the other hand, such 
deserts are likewise the home of many hoofed ruminants, 
such as the North African addax antelope and the 
Mongolian gazella. Again, the wild representatives of 
the South American llamas (which, in a collective sense, 
also come under the denomination of camels) are asso- 
ciated in their native wilds with the guemal deer, which, 
like the rest of its kind, has horny hoofs of the normal 
type. Moreover, the wild ^longolian ponies inhabit the 
same tracts as the half-wild camels of the same country. 
All that can be said, therefore, is that we must take 
facts as we find them ; and that, for some reason with 
which we are unacquainted, the members of the camel 
tribe have developed a type of foot quite imlike that of 
any other ungulates, and well adapted, although by no 
means essential, to the countries where these animals are 
found. Away from such tracts, the feet of camels are, 
however, not infrequently a source of inconvenience, or 
it may be absolute helplessness, to their owners. For 
instance, on the smooth ^' kankar " roads of the Punjab, 



which in wet weather become sticky and slippery, camels 
are utterly unable to progress, their washlealher-like 
padded feel sliding from under thorn, and rendering 
them as helpless as a cat on ice. 

.\lthough, m a literal sense — that is to say, from the 
fact that they "chew the cud" — the members of the 
camel tribe are ruminants, yet they are structurally very 
different from the true ruminants — the Pecora of zoolo- 
gists — and are consequently referred to a separate group 
of equal value, for which the aforesaid name of Tylopoda 
is now in general use. 

In addition to their cushion-like feet, camels (including 
now and hereafter all the existing members of the group 
and their immediate ancestors under this title) are 
broadly distinguished from the true ruminants by the 
following fc^itures : — 

In the first place, instead of having the front of the 
upper jaw entirely toothless, the full series of three pairs 
of incisor teeth are present in the young, while in the 
adult the outermost of these pairs are an isolated curved 
and pointed tooth, and there is also a well-developed 
pair of canines, or tusks. Again, the lower canines, in 
place of being approximated to the incisors and resem- 
bling them in shape, retain the more usual isolated posi- 
tion and sharply-pointed form. As regards the cheek- 
teeth, although the majority of these are of the crescentic 
type characteristic of all ruminating mammals, yet there 
are certain peculiarities in form whereby they are readily 
distinguished from those of the true ruminants; and, 
what is more important still, one or more at the front of 
the series are usually detached from those behind, and 
assume a sharply-pointed form. 

In the skeleton the thigh-bone, or femur, is placed 
much more vertically, by which means the thigh is 
much more distinct from the flank, while the knee-joint 
is placed lower down than in the true ruminants. Another 
peculiarity is to be found in the unusual length and 
pointed form of the knee-cap, or patella. Then, again, 
none of the bones of the wrist and ankle-joints Ccarpus 
and tarsus) are welded together. As regards the lower 
part of the limbs, although the upper segments of the 
two remaining toes (the third and fourth of the typical 
series of ti\e) are welded together to form a cannon- 
bone (fig. I); yet they diverge to a much greater extent 
at their lower extremities than is the case with the true 
ruminants. Moreover, in place of each of the two lower 
articular surfaces of the cannon-bone having a projecting 
ridge to fit into a groove in the upper surface of the 
uppermost toe-bone, such surfaces are perfectly plain 
and smooth (fig. 1). Probably, owing to the nature of 
the foot itself, there is less liability to dislocation than in 
the hoofed feet of the true ruminants, and a " tongued 
joint " is therefore unnecessary. As regards the toe- 
bones themselves, it will suffice to say that the third or 
terminal pair form small irregular nodules, quite unlike 
the symmetrically flattened form characterising those of 
the true ruminants. 



26 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



Perhaps, however, tht- ni'-i important peculiarity in 
the skeleton of the camels (and it will be unncessary on 
this occasion to refer to the soft-parts) is to be found in 
the vertebra- of the neck, which are unusually elongated. 
In all other mammals, with the exception of the extinct 
South American macrauchenia, the canal for one of the 
great arteries for the neck perforates the process pro- 
jecting from each side of the \ertebra' : but in the 
camels and macrauchenia it runs obliquely through the 
side- wall of the tube for the spinal marrow. 




Fig. 1.— Front Cannon-Bone of a Camel. 

All these features combined ser\'e to show that the 
camel tribe is widely separated from the true ruminants. 
How far back we have to go before we come to the 
common ancestral stock is indeed at present uncertain. 
Possibly both groups are independently derived from 
primitive ungulates in which tlie cheek-teeth had not yet de- 
veloped a crescentic type of structure. lie this as it may, it is 
quite certain that the ancestral camels had low-crowned 
cheek-teeth, comparable to those of the ancestral horses. 

Indeed, making due allowance for the fact that in the 
one case the modification has been carried on the artio- 
dactyle, and in the other on the perissodactyle plan (that 
is to say, with the enlargement of the third and fourth 
toes, instead of the third alone), the evolution of the 
camels has followed much the same lines as that of the 
horses. And this is only whatjmight have been expected, 
since, as stated in the previous article of this series, it is 
only on such lines that we can conceive evolution of this 
nature to be possible. 

/\s examples of this general similarity, or parallelism, 
I may refer, in the first place, to the enormous 
increase in bodily size which has taken place. Equally 
noticeable is the elongation of the bones of the lower 
segments of the limbs, coupled with the tendency to 
do away with double bones in such of those seg- 
ments as they exist, the suppression of the lateral 
digits, and the enlargement of those which remain. In 
both cases there is likewise a progression from low- 
crowned to tall-crowned cheek-teeth, and in both the 
development of a bar of bone beyond the eye so as to 
enclose its socket in a complete bony ring. 

The combination of all these factors tends (in addition 
to the augmentation of bodily size) to increase the 
speed and the longevity of the animals, and at the same 



time to render them fitted to subsist on the vegetation 
characteristic of the present and immediately preceding 
epochs ; the strengthening of the limbs so as to enable 
them to support the increased weight, and at the same 
time to withstand the strain of the increased speed, 
being, of course, an essential feature of the process. 

.^part from certain still older and more primitive mam- 
mals, with teeth of the tubercular type, the earliest known 
form which can definitely be included in the camel series 
is Piotylopiis, of the Llinta, or Upper Eocene period of 
North America. In this creature, which was not larger 
than a European hare, there was the full typical number 
of 44 teeth, which formed a regular series, without any 
long gaps, and with the canines but little taller than the 
incisors, while the hinder cheek-teeth, although of the 
crescentic type, were quite low-crowned. In both jaws 
the anterior front teeth were of a cutting and compressed 
type. Unfortunately, the skull is incomplete, and the 
rest of the skeleton very imperfectly known ; but sufficient 
of the former remains to show that the socket of the eye 
was open behind, and of the latter to indicate that in the 
hind foot, at any rate, the upper bones of the two func- 
tional toes had not coalesced into a cannon-bone. The 
lateral hind toes (that is to say, the 2nd and 5th of the 
typical series) had, however, already become rudimentary ; 
although it is thought probable that the corresponding 
digits of the fore-limb were functional, so that this foot 
was four-toed. \'ery remarkable is the fact that in old 
individuals the bones of the fore-arm (radius and ulna) 
became welded together about half-way down, although 
they remained free above. (_)n the other hand, it appears 
that the smaller bone of the leg (fibula) was welded to 
the larger one (tibia), and that itp upper portion had dis- 
appeared. Nothing is known of the neck-vertebra'. It 
is, of course, evident that there must have been an earlier 
form in which all the feet were four-toed, and the bones 
of the fore-arm and lower part of the leg separate. 

A stage higher in the series, namely, in the Oligocene, 
we meet with the much" better known Porhiotlieriuni, the 
skull of which (fig. 2) was described so long ago as i>^\'/. 
In this animal, which is also American, a distinct increase 




Fig. 2.— 5lvuli of Poebrotlierium 

in bodily size is noticeable, as is also one in the relative 
length of the two bones which unite in the higher types 
ot form the cannon-bone. Moreover, the crowns of the 
hinder cheek-teeth are rather taller and more distinctly 
crescentic, both feet are two-toed, the ulna and radius 
were fused, and the fibula was represented only by its 
lower part. In the vertebra^ of the neck the distinctive 



Mar., 1904.] 



KNO\VI.i:iH}E & SCIENTIFIC NEWS. 



27 



cameloid characters had already made their appearance. 
On the other hand, the skull (lie;. 21 was short and 
rabbit-like, showing none of the characteristic features of 
those df the modern canu'ls. 

Reaching the period of the Lower Miocene, we come 
to a genus, Gomphothtrium, in which there is a consider- 
able increase in the matter of bodily size, the two meta- 
podial bones (or those which unite in the later forms to 
constitute the cannon-bone) being fully double the length 
of the corresponding elements in Pivtylopus. Moreover, 
these bones, although still separate, ha\e their adjacent 
surfaces much more closely applied than is tiie case in 
the latter, .\gain, in tiiis and the earlier genera the 
terminal toe-bones indicate that the foot was of the 
normal hoofed type. On the other hand, in the skull 
(fig. 2) the socket of the ej'e is completely surrounded by 
bone: while the dentition begins to appro.vimate to the 
camel type — notably bj- the circumstance that the lower 
canine is either separated by a gap from the outermost 
incisor, or that its crown assumes a backwardly curved 
shape. Brief mention must suffice for I'roiolalris of the 
Middle Miocene, in which, while no cannon-bone is 
formed, the first and second pairs of incisor teeth are 
retained, and the limbs and feet are short and dispro- 
portionately small. 

In the Upper Miocene, on the other hand, we come to 
a very distinct type — Procamchis — which is clearly entitled 
to be regarded as a camel, and approximates in size to 
a small llama. Here the metapodials have at least 
partially united to form a cannon-bone : the skull has 
assumed the elongated form characteristic of modern 
camels, with the loss of the first and second pairs of 




rig. 3. — The Bones of the Mind-Foot of Poebrotherjum, showinf; the 
distinct metatarsars. uhich coalesce in the higher forms into the 
cannon -bone. 

upper incisors, and the development of gaps in front of 
and behind each of the next three teeth, that is to say, 
the third incisor, the canine, and the first cheek-tooth. 
The approximately contemporaneous Plianclienia makes 
another step by the loss of the second lower cheek-tooth. 
Both these genera have the toe-bones of the irregular 
nodular form distinctive of the modern camels, so that 



we may safely infer thai ihe fici themselves had assumed 
the cushion type. 

In one species of Pi'ocininiiis llic iiict.ipoilial hones 
coalesced into a cannon-bone late in life; but when we 
come to the Pleistocene Caiiiclops such union took place 
at an early stage of existence, and was thoroughly com- 
plete. In the living members of the group it occurs 




Fig. 4. Hind Cannon-bone of a modern Llama to contrast with the 
foot of ' ' f'oebrotheriiim,'* and to show the type characteristic 
of " Procamelas" and hlg:her forms. 

even before birth. The species of Camelops were pro- 
bably fully as large as llamas (including guanaco and 
vicuna), and some of them, at any rate, resembled these 
animals as regards the number of teeth, the incisors 
being reduced to one upper and three lower pairs, and 
the cheek-teeth to four or fi\-e in the upper and four in 
the lower jaw ; the total number of teeth thus being 
28 or 30 in place of the 44 of Poehi-otlieii'mn. Tiie sole 
difference between Camelops and Llama seems to consist 
in certain structural details of the lower cheek-teeth. 
An allied extinct genus (Kschatiui) is also distinguished 
by certain features in the dentition. 

All the foregoing genera are exclusively North 
,\merican. \ lower jaw from the F'leistocene deposits of 
that Continent has, however, been referred to the true 
camels (Camelas), w^hich differ from the llamas, among 
other features, by their greater bodily size, well developed 
hump, or humps, the presence of five pairs of lower 
cheek-teeth, and the complete bony ring round the socket 
of the eye. 

Outside America, remains of true camels are met with 
in the Lower Pliocene Siwalik strata of India, as well 
as in the Pleistocene of Soutli-Eastern Lurope and 
Algeria ; and it is noteworthy that the cheek-teeth of the 
Siwalik camel {Camelus sivalensis) display a structural 
feature now exhibited by those of the llamas. Prom 
Pleistocene or Pliocene in China have been obtained 
remains of a large camel-like animal named Paracamelus, 
which also shows certain signs of afiiiiity with the llamas 
in respect of its cheek-teeth. 

The above survey, brief as it is, suffices to show that 
the huge camels of the present day have been gradually 
e\olved from creatures not bigger than a hare, on lines 
closely paralleled in the case of the horse. In one 



28 



KNOWLEDGE & SCIENTIFIC NEWS. 



I Mar., 1904. 



respect the camels have indeed beaten the horse, haMn.^ 
entirely got rid of the splint-bones representing the outer- 
most pair of the original four toes. Further, in having 
exchanged the hoofed for the cushioned type of foot, they 
have undergone a kind of retrograde de\elopment. for 
which there is no parallel in the horse line. 




Fig' S. — Skull of Modern Camel, showing the reduced number of upper 
incisor teeth, and the ring of bone round the eye-socket. 

Here a brief diversion must be made to notice an 
extraordinary North American Miocene form, which is off 
the mam line. This is the giraffe-necked camel (Alti- 
camdas), a creature of the size of a giraffe, with similarly 
elongated neck and limbs, and evidently adapted for 
browsing on trees. The feet and number of teeth were 
generally similar to those of Procamelas. Unlike the 
giraffe, the length of the limbs is due to the elongation 
of the bones of the upper segments (femur and tibia) and 
not the cannon-bones : while the fore-limbs are not 
higher than the hind ones. The length of neck is due 
to the elongation of the anterior neck-vertebra-; if the 
hinder ones had been lengthened, the hei.ght of the body 
would have been increased without any compensating 
advantage. This creature affords one of the most extra- 
ordinarv instances of special adaptation known to science. 

The remaining space at my disposal must be devoted 
to certain considerations concerning the birth- 
place and geographical distribution of the group. 
It is claimed by Transatlantic pahfontologists 
that North America was the original home of 
the Camelidii, and so far as the earlier members 
of the group are concerned, there is nothing at 
present to justify a contradiction of this. The 
case is, however, \-ery different with the latter 
forms. We have seen that in North America 
the formation of a complete cannon-bone did 
not take place till tlie Pleistocene, at which 
epoch true camels also made their first appear- 
ance. But such camels, with complete cannon- 
bones, were in existence in India in the early 
pliocene. Ob\ iously, therefore, the evolution ot 
these animals must have taken place somewhere 
in Asia; this \iew being supported by the oc- 
currence there of the aforesaid Pnraeamelas. 
1 lence it is quite probable that some of the 
earlier stages of the evolution of the group may 
have been carried out in ;\sia, when that conti- 
nent was united by way of Pehring Strait with 
North America. The Siwalik camel, it may be 
added, may ha\'e gi\en rise totlie existing two- 
humped Bactrian species ; while from the ex- 



tint t Russian and Roumanian camels the single humped 
Arabian species may have sprung. 

W'ith regard to the llamas of South America, palaeonto- 
logy goes to prove that the ancestral forms first 
obtained entry into that contintent from the north dur- 
ing the Pliocene period, when free communication 
was established between North and South America. 
Now all these ancestral forms, of which there are several 
distinct generic types, appear to have complete cannon- 
bones. Consequently, unless we are prepared to admit 
that these compound bones have been independently 
evolved in the camels and the llamas, the latter cannot 
have been derived from the known North American 
Pliocene forms, in which the union of the constituent 
elements of these compound bones was incomplete. 
Consequently, it seems a probable supposition — and this 
is supported by the above-mentioned structural resem- 
blance between the cheek-teeth of the Siwalik camel and 
those of the llamas — that the latter animals, like the true 
camels, were evolved in Eastern Central Asia, whence 
they reached South America by way of the Pacific 
border of the northern half of the New World, possibly 
over land long since submerged. 



The PKotogroLphy of 
Electric Spa^rks. 



The Photography of Some Electrical Phenomena 
was the subject of a lecture delivered on January 25, 
1904, at the Camera Club, Charing Cross Road, by Dr. 
George H. Rodman. 

The lecturer commenced by describing t!ie method 
that he had adopted in obtaining the photographic repre- 
sentation of electric sparks from a lo-inch induction coil 
actuated by accumulators. It seemed to matter but little 
what voltage was used in the primary circuit, and the 
results shown were produced at a voltage varying from 
fi to 24 in the primar)'. 




Single Fo.siiive Di.scharge. 



Mar., 1904.] 



KNOWLEDGE c^- SCIENTIEIC NEWS. 



Sinsjle and multiple discharges were discussed ; the 
former occupying a very short space of time, possibly 

about of a second. Numerous representations of 

20.000 '^ 

sparks taken under different conditions were shown, and 




Single Discharg:c bL-twccn Points. 

attention was called to the marked difference between 
the positive and negative discharge, the former having a 
brush-like appearance, and the latter invariably showed 
a characteristic fern-like representation on the plate. 

The lecturer showed excellent examples of the in- 
creased intensity of the spark when a spark gap was 
introduced into the secondary circuit, and in passing re- 



.Single Positive Discharge on Florir. 

marked that this was the e.xplanation of the use of a 
spark gap employed in connection with the sparking 
plug of motor vehicles. 

Examples of sparks from brushes and spheres, in addi- 
tion to ordinary point discharges, revealed many extra- 
ordinary effects ; and in all the characteristic features of 



the positi\e and negative discliarges were invariably 
present. The results. Dr. Kodman cxphiined, were 
obtained on Imperial platfs, wliicli were subsiMiuentiy 
developed in the usual manner with a pyio suda 
solution. 

The production of the photographic image of 
coins placed on the surface of the emulsion, and 
connected up with one or other terminals of 
the coil furnished some highly interesting 
results; and in these cases the characteristic 
features of the positive and negative discharges 
were well shown. 

On passing a single discharge on these coins 
with subsequent development of the latent 
image, a very distinct representation of the coin 
with its inscription clearly legible was produced, 
and the same effect was obtained in a much 





Single Negati\e Discllarge on Coin. 

clearer manner when a multiple discharge of 
current extending to i-2oth sec. was used. 

In this experiment when a discharge was 
produced with two coins attention was called 
to the remarkable appearance that the plate on 
development presented — the image of botli 
coins being multi])le. Dr. Rodman stated that 
he had up to the present been unable to deter- 
mine the cause of these multiple images, and, 
in order to arrive at a conclusion as to the 
cause of these nimbus-like shadows, had adopted 
various devices, but had failed with them to elucidate 
the matter. 

Assuming that they were the result of reflection, films 
had been used instead of the glass plates employed in tlie 
other experiments. Backed plates had also been made 
use of, but the multiple shadows still presented them- 
selves. To exclude the possibility of their being pro- 



30 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



duced by retiection from the edf,'es of the coins, these 
had been painted with non-actinic colour. 

Finally, it was thought that the coins might have been 
thrown into a state of agitation, and had mo\-ed daring the 
passag'e of the current, and to exclude this possibility 




trend taken by speculations as to its origin. They have 
become more subtle, more far-reaching, yet less confi- 
dent. They have ramified in unexpected directions, but 
rather tentatively than with the full assurance of attain- 
ing absolute truth. Laplace considered only the solar 
system, from which he arbitrarily e.xcluded 
comets ; on the \ast sidereal world he 
bestowed barely casual attention. Sir 
William Herschel, on the other hand, 
occupied himself exclusively with the 
growth -processes of nebuUf, relegating the 
details of planetary evolution to a position 
of secondary importance. Later, the spectro- 
scope having become available for dis- 
criminating generic difl'erences among the 
suns in space, their relative ages, the order 
of their succession, their mutual affinities, 
laimed predominant attention. Just now. 



Sinj^le Positive Oischarge on two Coins. Both Coins in .Spherical Connection. 



they had been enclosed and supported in a couple ot 
circular holes made to fit the coins in a card at the time 
of exposure. This peculiar feature of the experiment 
was met with when coins of unequal size and of varying 
metals were employed, and was also noticed when the 
glass insulating plate was replaced by an india-rubber 
pad. 

Modern Cosmogonies. 

VII. Cosmogony in the Twentieth 
Century. 



By Miss .\gnes Clerkk, F.K.A.S. 
pROSPECTl\E and retrospectix e inquiries into physical 
conditions stand \ery much on the same footing. The 
same degree of uncertainty attaches to results of both 
kinds ; the same qualifications need to be applied to 
them ; a similar reserve is understood to accompany our 
admission of them. The reserve grows more marked 
as science unfolds to our surprised apprehension the 
multiplex possibilities of Nature. The time has gone by 
when " men of light and leading " could draw cheques 
for unlimited amounts on the bank of public credulity. 
Not that the balance has diminished, but that it is other- 
wise employed. Most of us, in these days, have learnt 
to "look before and after" for ourselves; and we in- 
stincti\ely mix the pr(j\erbial grain of salt with what is 
told to us, even on the highest authority. Ideas are on 
the move ; dim vistas are opening out ; much that lies 
lieyond the verge of actual experience is seen to be 
possible, and sedate reasoning may at any moment 
suffer outrage by fantastic discovery. Hence, dogmatism 
is at a discount. 

The secular parallax allccting men's views of the 
universe is nowhere more strongly apparent than in the 



however, the flood of ideas is too high to 
be restrained within separate channels ; 
cosniogonists look far afield ; they aim at 
obtaining a general sur\ey of relations 
baffling in their complexity. To some ex- 
tent they have succeeded ; parts are 
beginning to find their places in a great 
whole ; links are seen to connect phenomena 
at first sight seemingly isolated ; on all 
sides, analogies are springing into view. 
The unwearied circling of the moon, and its 
imperturbable face, remind us how a sun 
may have been born ; the fiash of every 
meteor suggests the mode by which suns die. 
The filmy traceries of comets intimate the nature of the 
force acting in nebulae ; the great cosmic law of 
spirality is distantly hmted at by the antipodal disturb- 
ances of the sun. Thus, one set of facts dovetails 
into the next ; none can be properly considered apart 
from the rest. 

The limitations of the human mind, nevertheless, 
require a subdivision of labour. Individual efforts can- 
not grapple with the whole of the known and the know- 
able ; and the larger part of both is included in the scope 
of modern cosmogony. It deals with all that the skies 
hold, visibly or invisibly ; draws unstintingly on time 
past and time to come ; concerns itself equally with 
gradual transformations and sudden catastrophes, with 
the dissipation and concentration of energy, with the 
subtle interplay of matter and force, with physical and 
ultra-physical, chemical and electrical modes of action. 
But let us consider a little more particularly how things 
actually stand, so as to collect some definite ideas regard- 
ing the lines of advance practicable and promising for 
the immediate future. 

To begin with our domestic circle. The insecure state 
to which Laplace's scheme has been reduced by the 
assaults of numerous objectors has found compensation 
in the development of tidal theory. Much light has 
thereby been thrown upon planetary pre-history. The 
relations of planets to the sun, and of satellites to planets, 
have been rendered comparatively intelligible. Notice- 
able above all is the discovery thence ensuing of the 
earth's critical situation, just outside the boundary of the 
region where planetary rotation was destroyed by sun- 
raised tides, and with it the prospects of planetary 
vitality. Moreover, the consequent dubious state of the 
inchoate terrestrial spheroid accounts for the peculiar 
mode of birth of the moon, and the distinctively binary 
character of the earth-moon system; while the variety 
perceptible in the circumstances of the different planets 
precludes the employment of any single recipe for their 



Mar., 1904.] 



KNOWLEDGE c\: SCIENTIFIC NEWS. 



31 



development from a primal vortex. The forces concerned, 
we can now see, acted in a far more complex manner 
than could formerly have been supposed ; and their 
balance was proportionately more delicate. To which 
side it would have inclined in a given case must tiien 
often be incalculable, or calculable only with the guid- 
ance of the known result. The strict bonds of reasoning 
have tlius become somewhat relaxed, and difficulties tiiat 
looked formidable have, in the long run, proved not to 
be insuperable. But conviction has also grown faint. 
The old, imposing fai;ade of theory remains erect ; the 
building behind it has been for the most part pulletl to 
pieces, and the architect has yet to be found who can 
reconstruct it to our satisfaction. 

On one point we have, nevertheless, acquired certainty. 
It is now known that comets with their dependent trains 
of meteors are aboriginal in the solar system. They are 
no unlicensed intruders, but collateral relations of the 
planetary family. Possibly, they represent waste scraps 
of world-stuff which escaped the action of the formative 
machinery ; and if so, they exemplify its primitive tex- 
ture. Not that their composition need be, on this sup- 
position, identical with that of the planets. A sifting of 
elements would have been likely to accompany the pro- 
cesses of cooling and contraction. Comets were perhaps 
made (so to speak) of the white of the nebulous egg, 
planets of its yolk. But in any case, we may safely 
regard the glimmering fabrics of acetylene and cyanogen 
that occasionally illuminate our skies as shearings from 
a wide-spreading, fleecy haze, flung aside before " the 
starry tides " had as yet begun to " set towards the 
centre." In one respect, the quality of these relics is 
a surprise. They show no chemical affinity with 
nebula?. Their spectra are radically different from 
nebular spectra, gaseous or continuous. They accord- 
ingly lend no countenance, although not fatally adverse 
to the view that the sun was once, in the distinctive 
sense, a nebulous star. 

The grand topic of sidereal succession is no longer 
abandoned to fruitless surmises. Broad lines have been 
laid down, along which — so far as we can at present see 
— progress must inevitably have been conducted. And 
one fact of overwhelming significance in this connection 
is entirely of recent discovery. The multitudinous 
existence of obscure bodies in space had, indeed, been 
foreseen as a logical necessity long before Bessel founded 
the " Astronomy of the Invisible" ; but it has been sub- 
stantiated almost wholly by modern spectrographic 
methods. Decrepit or dusky suns are assuredly no 
imagmary product, but a potent reality ; though it 
would be too much to assert that all have sunk to 
extinction by the same road. 

We stand, too, on firmer ground than our predecessors 
in respect to the history of stellar systems. That its 
course is mainly prescribed by the influence of tidal 
friction has been ably demonstrated by Dr. See. Tele- 
scopic double stars can be led back, by the aid of this 
clue, to an initial stage, when they revolved close 
together, very much like the earth and moon in Professor 
Darwin's theory ; and it was owing to their v oluminous- 
ness, and the unequal attractions it engendered, that 
their orbits became enlarged and elongated to the degree 
generally observed. Spectroscopic binaries, moreover, 
illustrate earlier modes of circulation ; they present us 
with couples fully separated, and still separatmg, as well 
as with others barely divided, and revolving almost in 
contact. Nay, they include specimens, we are led to 
believe, of globes conjoined into the apioidal figure 
theoretically investigated by Darwin and Poincare, 
which may be regardedas preparatory to the dev elopment, ' 



by iission, of two mutually revolving stars from one 
primitive rotating mass. One of these supposed dumb 
bell systems is the variable V Puppis ; and if tlie eclipse- 
rationale of its obscurations be confirmed by the spectro- 
scope, there is no gainsaying the inference that it is com- 
posed of two stars actually contiguous, if not commingloil. 

Now compound stars are by no means of exceptional 
occurrence. Their relative abundance has been found 
to augment rapidly with every advance in our knowledge 
of the lieavens. From the measures of stellar radial 
velocity lately carried on at the Ycrkes Observatory by 
Professors l'"rosl and Adams, it appears that the propor- 
tion of binary to single stars considerably exceeds Pro- 
fessor Campbell's earlier estimate. Of those giving 
helium-spectra, at any rate, there are most probably as 
many of one kind as of the other. But why the distinc- 
tion, it may be asked ; and the answer is not far to seek. 
Helium-stars are the most primitive, and form the 
closest, and most readily apparent systems. A 
physically double star must always remain such. 
There is no law of divorce by which it can put away its 
companion, although their relations must alter with time. 
But their alteration tends continually to enhance the 
difficulty of their detection. For as the members of a 
pair are pushed asunder by tidal friction, their velocity 
slackens, and the tell-tale swing of their spectral lines 
diminishes in amplitude, and finally, by its minuteness, 
evades observation. And since the majority of spectro- 
scopic satellite-stars are very imperfectly luminous, their 
eventual telescopic discovery, when far enough away 
from their primaries to be optically separable from them, 
would rarely ensue. It must then be concluded that half 
the stars in the heavens (let us say) broke up into two or 
more bodies as they condensed. What follows? Well 
this. Half the stars in the heavens were, from the first, 
incapacitated from becoming the centres of planetary 
systems. To our apprehension, at least, it appears 
obvious that a binary condition must have inhibited the 
operations of planetary growth. These innumerable 
systems are doubtless organised on a totally different 
principle from that regulating the family of the sun. The 
Nebular Hypothesis, even in its most improved form, has 
no application to them ; the Rleteoritic Hypothesis still 
less. Mathematical theories of fluid equilibrium, com- 
bined with a long series of changes due to tidal 
friction, afford some degree of insight into the mode of 
their origin and the course of their development. Yet 
the analogy with the earth-moon couple, which irre- 
sistibly suggests itself, is imperfect, and may be mislead- 
ing, owing to the wide difference in state between plastic 
globes approaching solidification and sun-like bodies, 
radiating intensely and probably gaseous to the core. 

The world of nebulae presents us with complete cycles 
of evolutionary problems, which can no longer be treated 
in the offhand manner perforce adopted by Herschel. 
The objects in (luestion are of bewildering variety ; yet 
we can trace, amid their fantastic irregularities, the 
underlying uniformity of one constructive thought. 
Nearly all show, more or less markedly, a spiral con- 
formation ;' and a spiral conformation intimates the 
action of known, or discoverable laws. 1 heir investiga- 
tion must indeed be slow and toilsome ; its progress may 
long be impeded by the interposition of novel questions, 
both in physics and mechanics ; nevertheless, the lines 
prescribed for it seem definite enough to give hope of its 
leading finally to a clear issue. And when at last some- 
thing has been fairly well ascertained regarding the 
past and future of nebulous spirals, no contemptible 
inroad will have been made on the stupendous enigma of 
sidereal relationships. 



32 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1934. 



Its aspect, if we venture to look at it in its entirety, is 
vast and formidable. Not now, as in former times, with 
a mere fragment of creation — a single star and its puny 
client-globes, one of which happens to be the temporary 
abode of the human race — but with the undivided, 
abysmal cosmos, the science of origin and destiny con- 
cerns itself. The obscure and immeasurable uncertain- 
ties of galactic history invite, or compel attention. We 
know just enough to whet our desire to know a great 
deal more. The distribution of stars and nebulae is easily 
seen to be the outcome of design. By what means, w-e 
cannot but ask ourselves, was the design executed ? How 
were things ordered when those means began to be em- 
ployed ? How will they be ordered when all is done ? For 
an ultimate condition has, presumably, not yet baen 
reached. And if not, agencies must be at work for the 
perfecting of the supreme purpose, which are not, 
perhaps, too subtle for our apprehension. Meanwhile, 
facts bearing on sidereal construction are being diligently 
collected and sifted ; and we shall do well to suspend 
speculation until their larger import is made known. 

The inquisitions of science do not cease here. They 
stri\e to penetrate a deeper mystery than that of the 
scattering in space of stars and nebulie. What are they 
made of is the further question that presents itself. 
What is the nature of the primal world-stuff? Whence 
did it obtain heat ? By what means was motion im- 
parted to it ? If it be urged that such-like topics elude 
the grasp of finite intelligence, and belong to the secrets 
of Creative Power, we may reply that we are not entitled, 
nor are we able to draw an arbitrary line, and impose a 
nc plus ultra on our thoughts. Tiie world has been, by 
e.xpress decree, thrown wide to their excursions, and it 
is not for us to restrict their freedom. W'e need not fear 
getting too near the heart of the mystery ; there is no 
terminus in the Unknown to which we can travel by 
express: in a sense, we are always starting, and never 
get nearer to our destination. But that is because it 
retreats before us. We do, in truth, advance ; and as 
we advance, the mists clear, and we see glimpses beyond 
of imperishable order, of impenetrable splendour. Our 
enquiries need not then be abandoned in despair at the 
far-reaching character they have spontaneously assumed. 
From the earliest times there has been a tendency to 
regard varieties of matter as derivative. They have 
been supposed to be procured, by supra-mundane agency, 
or by the operation of inherent law, from some universal, 
undifferentiated substance. We moderns call that sub- 
stance " Protyle,"" and believe ourselves to be in experi- 
mental touch with it. The implications of this view we 
shall consider in the next chapter. 

' A term signifying " first matter," constructed from corre-pjnd- 
ing (ireek words by Roger Bacon, and revived by Sir William 
Crookes. 

The Conductivity of Seleniunrv. 



Mr. E. A. llopius, in an investigation recently presented to 
the Russian Physico-Chemical Society, has made a series of 
experiments with an apparatus constructed by Mr. M. Kohl 
and another apparatus designed by himself on selenium sup- 
plied by the firm of E. MerU, Darmstadt, the former apparatus 
beinf; illuminated by a standard amy! acetate burner at dis- 
tances ranging from 10-200 cm., and the other by a Nernst 
lamp placed at the same distance. The measured current 
intensity agreed fairly well with the hypothesis of a direct 
proportionality between the increase in the conductivity of 
selenium and the cubic root of the intensity of illumination. 



Borings on Ql Corad 
IslacHLd. 



The Atoll of Fvinafviti. 



Xeari.v a quarter of a century ago Charles Darwin 
penned the following words in a letter to Prof. .Alexander 
Agassiz : " I wish that some doubly rich millionaire 
would take it into his head to have borings made in some 
of the Pacific and Indian atolls, and bring home cores 
for slicing from a depth of 500 or 600 feet." The pro- 
found interest which Darwin had himself long previously 
aroused by his theories regarding the structure of coral 
reefs and their mode of origin could not do otherwise 
than henceforth make the subject an integral part of 
geological science, and one. too, of striking significance. 
It was, therefore, to be expected that the hopeful 
words of the master-naturalist would ripen with time 
to bear fruit in effort. Not, however, until 1893 did 



Sand iv/'t/i some cora/ b/ocks. 









■M. 


■52 ft. 9 in. 


'■■'<a.-: 




m 




i 


65 n. 


1 




■^ 


/06ft. 





Cora/ reefs and blocks iv/Ch 
■some se.nd. 



Sand ivitb some cora/ b/ocks. 



Fig. 1.— Structure of abandoned Bore.hole, Expedition i.Sc,6. 

a project for such a survey become fairly launched, and 
then chiefly through the strenuous endeavours of Prof. 
W. J. S"illas, F. R.S., who succeeded in at last promoting a 
"Coral Reef Committee." Prof. T. G. Bonney, F.R.S., 
assumed the chairmanship, and on this body several of 
the most competent among English geologists, with 
other authorities, consented to serve. It is unnecessary 
to say that, whatever the latter-day millionaire may do 
for science, none made his appearance at this initial stage. 
The primary idea was to investigate, by means of a 
boring, the depth and structure of an oceanic coral reef, 
and thus make it tell its life story. Ultimately it was 
decided to attack the problems surrounding the question 
at Funafuti, an island in the Ellice Group in the Pacific 
Ocean, and a comprehensive scheme for an exploring 
Expedition was drawn up in i8g6. Professor Sollas 
being unanimously designated as leader. Although the 
difficulties that lay in front were by no means under- 
rated at the commencement, yet the news of the failure 
of the first attempt in 1896 was indeed unwelcome. 
(I-"ig. I.) However, nothing daunted, a second Expedi- 



[Mar., 1904. 



KNOWLEDGE & SCIENTIFIC NEWS. 



33 



tion was organised in 181)7, under tlie diieclion of Prof. 
T. \\". l-df;e\vorth David, of Sydnej', and a tliirdin i8y8, 
with Mr. .\. V. Finckh as leader, for the further prosecu- 




Flg, 2. — .Model of Atoll, showing tEcneral shape and Submarine contour. 



tion of the work. The (inal result was the achievement 
of a drill horint,' to the extraordinary depth of 1 1 14J feet, 
and the hrinyjinj^ of a cor ', by which means the coniposi- 

tion of an atoll in its 

zoological and chemical 
aspects has been actually 
determined. How re- 
i )ice<l the great naturalist 
iif Down would ha\ebeen 
(■.)uld he ha\e li\ed to 
witness the realisation ul 
his wish. We can pic- 
I ure his eagerness to write 
al once to 1 looker, and to 
Wallace and .\gassiz. 
I lis personal opinions re- 
garding the dcNclopment 
of coral reefs would not 
have weighed for an in- 
stant, since his open 
mind had already dictated 
the characteristic sen- 
tence, "if I am wrong, 
the sooner 1 am knocked 
on the head and annihila 
ted, so much the better." 

Although much scien- 
tific literature has centred 
around Funafuti in the 
inler\ening years, it has 
not been possible to 
pilot the whole scien- 
tific story of the borings 





Fijf. 3. — Hard Breccia Ma.ssts on Shore. 



34 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



to completeness until to-day, but it is now told 
in a handsome monograph just issued by the Royal 
Society, to which source we are indebted for our illustra- 
tions. 

The configuration of the atoll is seen on reference to 
the model (Fig. 2^, and its fanciful rescnblance to 



the shape of a human head (view from the compass 
letter S) has not escaped notice. The longest continuous 
stretch of reef is 16 miles in length, and the most elevated 
point abo\'e high water, 16 feet; while the general depth 
of the waters of the lagoon is about 20 fathoms. One 
peculiar feature of the atoll is its submarine cliflf, re- 




Fig. 4.— Hurricane Beach. Fcnafuti. and li\ing "Liihothamnion " kecr. 




Professor Edgeworth David 

the whole atoll elevated 

enable the portions 

present a clift" face 



Fiz- 5.— A Cluster ol the alga " Halimeda.' 



garding which 
remarks that were 
140 fathoms, it would 
above the sea-level to 
300-600 feet in height. 

Although we speak of Funafuti as a coral 
island, in its fauna corals are the accessory 
rather than the essential reef-builders, and 
of the latter none aie more abundant and 
contributory to reef-rock than the calcareous 
algae Litlwthamnioit and Halimeda. Indeed, a 
classification of the chief reef-forming or- 
ganisms assigns their relative importance 
thus: — (i) Species of Lithothamiiion, (2) Hali- 
meda, (3) Foramiiiifera, (4) Corah. And Mr. 
Mnckh, in a biological chapter, tells us, fur- 
ther, that a coral once established adds to 
the coral island by its growth only in the 
same way as a tree once established adds 
by its growth to the extent of a forest. In 
the living state and by itself it cannot form 
a solid mass ; dead, however, its skeleton 
supplies material which the Litlwthamnion and 
Halimeda unite together with the remains of 
other calcareous organisms to make reef-rock 
— mounting thus " On stepping stones of their 
dead selves to higher things." (Figs. 3, 4.) 

Some interesting e.xperimentswere conduc- 
ted relative to the effect of exposure to the 



Ua 



1904.] 



KNOWLEDGE >.^- SCII-XTIFIC NEWS. 



35 



sun's rays and the powers of endurance to lieat of 
corals and of Lithothaiimion, a point on which Darwin 
had speculated. It seems that except the Poiitcs, all 
other forms of coral succumbed within two hours' 
exposure, and it was evident that the essential life-gift 
alike to coral and plant was a constant supply of fresh 
sea-water. 

Among the contributions to the monograph certainly 
the most industrious of all is Dr. Hinde's report on his 
examination of thin sections of the materials obtained 
from the reef borings and those made beneath the lloor 
of the lagoon. Upwards of 500 microscopic surface 
slittings were prepared for diagnosis in Professor Judd's 
geological laboratory at the Royal College of Science. 
.\s already mentioned, the main boring, begun in 1897, 
was taken down to 1114^ feet, and it may be added that 
the diameters of the cores brought up in the drilling 
apparatus were, top to 68 feet, about 4 inches; 68-210 
feet, about 3J inches; 210 toboring limit, about 2| inches. 
.\11 these cores ranged in length from i inch to 3 feet. 
Dr. Hinde supplies an elaborate description of a detailed 
inspection of the several lengths of core that were placed 
under examination for the detection of organisms, and we 
cannot do better than quote here Professor Judd s general 
conclusion thereon, namely, that " from top to bottom the 
same organisms occur, sometimes plants, sometimes fora- 
minifera, and sometimes corals predominating ; but in the 
whole depth bored the same genera and species of these 
various groups of organisms take their part in the "build- 
ing up of the mass." (Fig. 5). 

.\ large amount of space would be necessary to even 
summarize the many points of research apart from 
boring and sounding operations embraced by this truly 
classic exploration in the far Pacilic. There was made, 
however, we must not omit to mention, a magnetic sur- 
vey by H.M.S. Penguin (Captain Field) ; a series of 
meteorological observations ; and a thorough study of the 
natural history of the island of Funafuti. 

The numerous helpers in the two continents have 
reason to be proud of the evidence of their long-continued 
efforts, and undoubtedly the scientific results of the sur- 
vey will prove of the utmost value in current discus- 
sions which concern the present-day re\ised \ iew of the 
development of coral reefs. 

Modem Views of 
Chemistry. 

By 11. J. H. Fenton, F.K.S. 



It may happen that there are some of our readers who 
are interested in the study of Chemistry, but who have 
not had the time or opportunity of following the very 
rapid and important advances which have been made 
in the science, especially in the departments of physical 
and organic Chemistry. In the present articles, which 
are addressed to readers of this class, it is proposed to 
give brief sketches in outline of some of the more im- 
portant developments which have occurred during recent 
years. 

We will in the first place refer to the great changes 
which have occurred in our views with regard to the 
nature of solution and the chemical and physical changes 
which may take place in dissolved substances ; the 
advance of knowledge in this department has resulted in 
what is sometimes called the •' New Cheniistr}-," which 



would scarcely be recognised as the same science by one 
who had been a good chemist twenty-livf years ago, hut 
who had not kept pace with the times. 

It may be mentioned in passing that it was the custom 
formerly to restrict the term "solution" to liquid mix- 
tures — that is to solids, liquiils, or gases dissolved 
in licjuids; hut we may now speak of solutions of 
gases in solids and even of solids in solids ; a solution 
IS in fact, generally speaking, any homogeneous 
mixture of two (or more) substances in which the pro- 
portions may, within certain limits, be varied con- 
tinuously. I'sually one speaks of one of the 
constituents as the solvent and the other as the dissolved 
substance or "solute " ; but this is only an arbitrary dis- 
tinction. In the case of an aqueous solution of common 
salt, for example, we might regard the mixture either as 
a solution of salt in water or of water in salt; for if a 
dilute solution be sufficiently cooled it becomes saturated 
with respect to water, and solid water (ice) separates out, 
leasing a stronger solution of salt, just as when a \'ery 
strong solution is cooled it becotnes saturated with re- 
spect to salt, and the latter separates in the solid state, 
leaving a weaker solution of salt, i.e.. a stronger solution 
of water. It was at one lime thought that solution con- 
sisted in a sort of loose chemical combination between 
the sohent and dissolved substance, and this idea seemed 
to be supported by the fact that many salts and other sub- 
stances combine with water to form definite hydrates, 
which may be isolated in the crystalline form. But it 
does not follow that tliese hydrates continue to exist 
when the substance is in solution, and the probability is 
that, in dilute solution at any rate, they do not exist. 

Certain membranes exist naturally, and may be pre- 
pared artificially, which will allow water to pass through 
them, but will not allow the passage of dissolved sub- 
stances such as sugar, salt, &c. If now one separates a 
solution of sugar from pure water by means of a mem- 
brane of this kind water will pass both ways through the 
membrane, but more will pass into the sugar solution 
than out of it, so that its volume tends to become larger 
and the solution weaker. If, however, the volume of the 
solution IS kept constant, that is, if it is not allowed to ex- 
pand, the pressure will increase instead, and will con- 
tinue to do so until a certain maximum pressure is 
reached. This maximum (osmotic) pressure depends 
upon the temperature, the strength (or concentration) of 
the solution, and the nature of the dissolved substance. It 
is found to vary with the temperature and concentration 
according to the same laws which regulate the pressure of 
a gas, and, further, the actual pressure produced is the 
same as that which would be exerted by the same sub- 
stance (theoretically in the case of sugar) if it were in the 
state of gas at the same temperature and volume. 

A large class of substances (such as sugar, urea, and 
most other organic substances) behave, therefore, in 
exactly the same way when dissolved in a solvent as 
they would in the gaseous state — as regards the relations 
between temperature, concentration, and pressure — only 
that what we understand by " pressure " in the gas state 
must be interpreted as "osmotic pressure" in the case of 
solutions. 

By making use of Avogadro's hypothesis— that ecjual 
\olumes of gases contain, at the same temperature and 
pressure, the same number of molecules — we can com- 
pare the molecular weights of gaseous elements or com- 
pounds by weighing equal volumes of them under the 
same conditions; and now by extending this hypothesis 
to substances dissolved in liquids we can compare their 
molecular weights in a similar way. It may be done in 
the latter case by measuring (directly or indirectly) the 



36 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



osmotic pressure which is produced at a certain tempe- 
rature and volume by a given weight of the substance. 

If we apply this method to the determination of mole- 
cular weights of substances in water solutions, it is found 
that, although most of the organic (and some inorganic) 
compounds give perfectly normal results — (results, that 
is, which agree with vapour density determinations and 
with general chemical considerations) — most salts, acids, 
and bases give results which are apparently abnormal, 
the osmotic pressure produced being too high. A dilute 
solution of potassium chloride, for example, gives an 
osmotic pressure almost exactly double of that to be 
expected by the application of Avogadro's hypothesis. 
That is to say that one molecular weight of potassium 
chloride gives twice the osmotic pressure which one 
molecular weight of sugar (urea, &c.) gives under the 
same conditions. 

It was suggested that this result might be explained 
by supposing that the salt is " hydrolysed " by the 
water — i.e., that caustic potash and hydrochloric acid are 
produced. Since they would be formed in exactly equi- 
valent quantities, it would not, of course, be possible to 
detect their presence by the ordinary tests. But such an 
explanation will not account for the fact that hydrochloric 
acid itself behaves " abnormally " also, giving about 
double the expected effect. 

The theory of Arrhenius not only accounts for all these 
"abnormalities," but offers in addition a most elegant 
explanation of a large number of facts in connection with 
the behaviour of salts and other substances in solution, 
including the phenomena of electrolysis. This theory 
assumes that most salts, and the strong acids and bases, 
are largely if not entirely dissociated when dissolved in 
water (and in some other solvents) into constituent parts 
or " ions," and that these ions differ from the same sub- 
stances, as we know them in the separated state, in that 
they are associated with enormous electric charges. A 
molecule of potassium chloride, for example, dissociates 
into an atom of potassium associated with a positive 
charge, and a chlorine atom with an equal and opposite 
negative charge. These charges are given up at the 
respective electrodes when the salt is electrolysed and 
the potassium and chlorine are obtained in their ordinary 
" neutral " state. 

A revolutionary hypothesis of this kind was viewed, 
perhaps naturally, in the first instance with suspicion and 
dislike, and even at the present day it is not quite univer- 
sally accepted, but the active opponents, at any rate those 
who have the courage of their opinions, are becoming 
daily few and far between. The application of 
this ionic dissociation hypothesis in explaining various 
well-known chemical phenomena is an extremely fasci- 
nating study and it is proposed to give various examples 
in illustration of the application at a future time, fust 
one may be mentioned here in conclusion. 

A question which agitated the minds of chemists for a 
great number of years was of the following form: What 
happens when two different salts— say, sodium chloride 
and potassium nitrate— are mixed together in aqueous 
solution ? Do they remain as they are or do they " change 
partners," forming sodium nitrate and potassium chloride? 
A large number of experiments were made with a view of 
throwing light upon this question, but in most cases the 
problem appeared to be incapable of solution. It was 
apparently of no use to attempt the isolation of the differ- 
ent salts since the equilibrium would be disturbed by their 
removal, and it seemed only admissibletn employ methods 
which required no removal from or addition to the solution. 
Attempts were made, for example, to throw light upon 
the problem by observing the thermal, volume, or colour 



changes which occurred on mixing the solutions, and 
although a certain amount of information was gained by 
such methods, they were in most cases anything but con- 
clusive. 

This much-debated question then — which metal is 
united with which acid-radicle ?— is (as a general case in 
dilute aqueous solutions) now at once disposed of by 
the ionic dissociation hypothesis, which gives the answer 
— No metal is united to any acid-radicle ! 

Wind-Driven Electricity 
Works. 



l>y Dr. Ali-red Gradenwitz. 



Professor Latour, of the Askov Popular Academy 
(Denmark), has for some years b^en engaged on behalf 
of the Danish (jo\'ernment in investigating the problem of 
utilising wind power in connection with small electricity 
works. If, however, the dynamo be direct-coupled to the 
wind motor, the results obtained are unsatisfactory on 
account of the exceedingly variable speed of the wind. As 
pointed out in an address recently delivered by Professor 
Latour before the Copenhagen Technical and Hygienic 
Congress, he was met with difficulties in designing a suit- 
able regulator for controlling the speed of the dynamo. 
At present, however, these difficulties appear to have 
been overcome, and an electricity central station near 
Askov has been worked with wind power for a year with 
satisfactory results. 

The arrangement of a similar electricity works is repre- 
sented diagrammatically in fig. i. The regulating device 
itself is made up of two different parts. The mechanical 
regulating device is intended for maintaining at constant 
values the peripheric force transmitted to the belt disc of 
the dynamo. The two belt discs R R are mounted on a 
movable arm A, bearing a counterweight P. The 
resulting tension of the belt is thus kept constant, depend- 
ing on the weight of the belt discs as well as on the counter- 
weight P. The ratio of the resulting belt tension and 
the maximum peripheric force susceptible of being trans- 
mitted by the belts is, however, practically constant. 
The peripheric force transmitted by the wind motor to 
the belt disc R accordingly cannot exceed a given value, 
the torque of the dynamo remaining below a corresponding 
value. Any surplus energy developed by the wind motor is 
lost as heat with the friction of the belt. A constant torque 
of the dynamo axle will, however, correspond with a 
constant current intensity in the armature. In the case 
of the magnetising intensity employed, the load is in fact 




Fig. I. 



M' 



1 004.] 



KNOWLEDGE .S; SCIENTIFIC NEWS. 



2,7 



practically proportional to the speed, so that the intensity 
of the current may be regarded as constant. This is 
further demonstrated by the author's measurements. 

The current from the dynamo is used to charge an accu- 
mulator battery represented diagramniatically in P'ig. i. 
The cut out switch F is closed, pro\ided the current in- 
tensity be not inferior to its normal constant value. The 
dynamo D therefore works at a variable speed. In the 
case of the wind being so strong as to absorb part of the 
energy by the friction of the belt, the system will work in 
the following way : .\ssummg the accumulator battery to 
be nearly discharged and the crank of the cell controller 
to be adjusted for the total charge of the battery, llie 
dynamo will run at a speed so high as to be quite suffi- 
cient to charge the battery with the normal current of a 
dynamo (e.g. 50 amp.). As the charge increases, the 
dynamo will automatically increase its speed and load 
so as to make the charging current constant. The cell- 
controller will have to be resorted to in charging in 
exceptional cases only — if, for instance, the charging 
and discharge of the battery takes place at the same 
time. 

The electrical regulating device is situated in the inter- 
rupter S, being mainly an ordinary minimum current 
interrupter, disconnecting the dynamo as soon as the 
current decreases below the normal number of amperes. 
This arrangement is necessary to prevent the accumu- 
lator battery from being discharged through the dynamo 
when the strength of the wind is small. The interrupter, 
however, will automatically insert the current as soon as 
the wind again assumes a greater strength. To attain 
this result, the current interrupter is provided with a ten- 
sion regulator, inserting the current as soon as the speed 
of the dynamo has sufficiently increased. In the case of 
variable strengths of the wind, the plant may thus accumu- 
late any amount of wind available, the interrupter open- 
ing and closing the connections continually. On the 
switchboard there are in addition two ammeters and one 
voltmeter. 

A small electricity works arranged in accordance with 
the foregoing principle has, as above mentioned, been in 
operation in Askov since the beginning of last autumn, 
supplying the inhabitants of the neighbouring commu- 
nities with electric current. The constant normal current 
supplied by this installation is 60 amps, at tension of 220 
volts. As a reserve, however, in cases of several days' 
calm weather, a petroleum motor had to be installed. 
The plant has so far given every satisfaction, requiring no 
superintendence worth speaking of. The man in charge 
of the machine was away fer|whole days, so that there 
was no supervision except "Jin^^the morning and the 




The W'ork.s at A.skov. 



evening. The capacity of the accumulator battery is 
sufficient to supply the maximum amount of energy 
required during 48 hours. As regards the economical 
side of the question : The (irst cost at .'VsK-on- has been 
about 16,000 Kr. (a Kroner is about is. id.), out of which 
3000 Kr. are set aside for the cost of pstroleum nioliir. 
The electric current is supplied to consumers at the 
same price as in Copenhagen. The receipts for energy 
sold work out at about 2800 Kr., and the expenses al 
about 800 Kr. per year. There will thus remain 
2000 Kr. for the amortisation of the plant, which is more 
than sufficient with a capita! of i6,ooo Kr. The price of 
energy could therefore be further diminished. In ihe case 
ofsniall electricity works intended for the use of a limited 
number of houses, the petroleum motor may be replaced 
by a horse-driven contrivance. Moreover, in the case of 
the proprietor of the works being his own consumer, the 
consumption of current may be regulated according to 
the actual intensity of the wind; in the case of calm 
weather, there will for instance have to be no thrashing 
done, cVc. The first cost will thus be considcraoly 
diminished; according to I'ref. Latour's calculation, a 
plant suitable for a farm would be installed at a cost of 
3000 to 4000 Kr. 

The Canals on Mars. 

Ix a communication to the Royal Astronomical Society 
on June 12, 1903, as reported in the Olwrvaloi'v for July, 
Mr. Maunder called in question the objective reality of 
the canals on Mars, explaining them away as psycho- 
logical phenomena " due to the integration by the eye 
of markings far too small to be observed by the observer." 
He based his argument on the fact that copies of draw- 
ings of Mars without the canals, made by beys of from 
12 to 15 years of age placed at \'arieus distances from the 
drawings, contained lines resembling canals amounting 
to five canals per head as a maximum at a distance of 
25 feet, the diameter of the disk being about 6 inches. 
Unfortunately, the report gives us no information as to 
the closeness of coincidence of the lines with canals that 
have been actually observed, nor even as to the agree- 
ment between the lines drawn by different boys. It is 
difficult to see hew the drawings to be copied could have 
contained actual Martian markings that were " far too 
small to be observed," whose integration produced lines 
in the positions in which canals have been observed ; 
but if the drawings were not sufficiently accurate to show 
such markings, the lines must have been produced by 
markings peculiar to the several drawings, whose resem- 
blance to anything on the planet is highly improbable. 
In drawing inferences from a comparison of artificial 
experiments with natural phenomena, it is certainly 
essential to the value of the results that the artificial and 
natural phenomena shall be substantially identical, and 
that the observations shall be made under practically the 
same conditions in both cases. On a later occasion, Mr. 
Maunder himself strenuously insists upon the necessity 
for a very close resemblance between the phenomena and 
between the conditions of observation in such cases. In 
criticising Mr. Lowell's application of the results of his 
experiments on the " visibility of fine lines " (the Oliscrva- 
tory for September, 1903), Mr. Maunder says "there is 
actually no resemblance between the case of observing a 
wire in space and that of observing a line drawn on a 
surface " ; nevertheless, he seems to find a sufficiently 
close resemblance between the observation of a flat 
picture (inaccurate, at best) with the naked eye in a 



38 



KNOWLEDGE .K: SCIENTIFIC NEWS. 



[Mar., IC04. 



lighted room, and the observation of an illuminated ball 
surrounded by the blackness of night, seen through the 
mirage of its own atmosphere by means of a telescope. 
Those who draw conclusions from observations should be 
very careful in their reasoning, bearing in mind that 
induction, while a powerful instrument in the construc- 
tion of theories, is absolutely useless in their proof or 
disproof. A theory of physical phenomena can be dis- 
proved only by showing that it leads by deductive 
reasoning to necessary conclusions that are inconsistent 
with observed facts. ;\Ir. jMaunder's theory may explain 
sufficiently well the lines on the copies of his drawings, 
but it no more suffices to disprove the objective reality 
of the canals observed on Mars than it does to prove 
that there are only fi\-e canals, as seen by his boys. 
The fact that an effect may be due to one cause, while it 
may certainly also be due to another, affords no pre- 
sumption that it is due to the first rather than to 
the second, especially when the one explanation is 
based upon artificial experiments and the other is 
natural. 

Mr. Maunder's argument assumes that the canals are 
seen as very faint lines, so faint that their existence is 
doubtful even to experienced observers ; this may be true 
when they are observed through any but an exceptional 
atmosphere — and the atmosphere of Flagstaff is one of 
the exceptions. There, even under ordinary conditions, 
at the proper Martian season most of them are so easily 
and certainly seen that there is no reasonable doubt about 
them. Before Mr. Maunder ever disco\ered the psychical 
effect, Mr. Lowell was perfectly aware of it himself, and 
had studied it experimentally, which experiments he has 
continued to the present time, with the result that he 
finds a clear line of demarcation between confusion of 
real and imaginary up to a certain degree of definite- 
ness of the real, and an instant consciousness of the dif- 
ference between the two above that limit. The brain is 
not only conscious of the image, but directly conscious 
of reality as opposed to illusion. If Mr. Maunder's 
drawings had contained some canals for comparison 
with the imaginary lines, this difterence would probably 
have been apparent. 

The beha\iour of the canals, their waxing and waning 
with the advance of the Martian seasons, is proof positive 
that they are not due to the integration by eye of perma- 
nent faint markings, and it is more difficult to account for 
the gradual and regular advance and retreat of such 
markings along the line of a canal than for the growth 
and decadence of the canal itself. Mr. Maunder's ex- 
planation seems to substitute an uncertain and almost 
impossible phenomenon for a very certain and probable 
one._ From 8,500 determinations of the canals, Mr. 
Lowell has recently shown that they come into sight 
after the melting of the polar cap in times that are 
directly proportional to their distances from that cap 
measured in latitude. The enormous improbability of 
any such agreement in 375 drawings, the number he 
used, is so great as to run into the millions to one. 

The logical conclusion of Mr. Maunder's argument, if 
valid, is that no faith is to be put in the reality of things 
seen, if anybody has e\ er been deceived in the appearance 
of such things. The scientific \-alue of facts would then 
be liable to complete emasculation by the ignorance 
carelessness, or male\olence of an observer. It is time 
an end should be put to the inquisitorial fashion of re- 
fusing credence to scientific discoveries until they shall 
have received the official recognition of the self-constituted 
authorities, especially when those authorities do not 
represent experts in the subject in (juestion. That it is 
useless to continue the observation of planetary detail, 



because henceforth no reliance can be placed on what 
observers may tell us they have seen of such, can only be 
the doctrine of what may be called an " impressionist " 
school of science. If Mr. Maunder claims that his ex- 
planation is simply one mode of accounting for the 
appearance of the canals, he is practically throwing 
doubt upon their existence without taking the responsi- 
bility for it. 

In the course of the discussion of Mr. ]\Iaunder's com- 
munication, Professor Newcomb said : " We all know 
how one improves by practice, and I think there is such 
a thing as improvement of the art of seeing things dif- 
ferent from what they really are." This is a gratuitous 
slur upon scientific obser\ation, to be justified only by 
the heat of a violent quarrel, and inexplicable under the 
present circumstances. Surely, Professor Newcomb 
cannot believe that the statements of an observer are 
any the less credible because he has had experience ? 
No ; these experiments show conclusively that observers 
must be trained to their work, that even descriptions of 
phenomena are of little value unless made by those who 
are experienced in observing phenomena of the kind de- 
scribed. The reports of such observers must be accepted 
as truly indicative of fact until they shall have been 
proved to be false, which can be done only by direct 
appeal to observation. Williaii Edward Story. 

Worcester, Mass., U.S.A., January 2, 1904. 
[Mr. Story criticises the paper communicated by Mr. Evans and 
myself to the R AS. without first having done us the honour 
of reading it. This method has some disadvantages; one being 
that many of Mr, Story's remarlis have no bearing at all on the 
questions with which we actually dealt. Want of space pre- 
vents my dealing with the details of Mr. Story's paper in the 
present number of "Knowledge," but if the subject suffi- 
ciently interests its readers I may return to it on a later occasion. 
For the present, it is sufficient to enter a strong protest against 
Mr. Story's quite uncalled-for attack upon Professor Newcomb. 
— E. Walter Malnder.] 

The Obelisk of Mo\ii\t 
Pelee. 



Wb. reproduce herewith a remarkable photograph taken 
by Mr. E. O. Hovey, for which we are indebted to our 
contemporary, the Scientific American. It represents one 
of the most peculiar and interesting phenomena of the 
recent eruptions of Mount Pelee. This was the growth 
of the tooth-like column of rock which arose out of the 
centre of the crater. It was first observed (by Professor 
Lacroix) in October, 1902, amid the dense smoke and 
steam overhanging the mountain. It was then estimated 
to be about 295 feet above the rim of the old crater. Put 
subsequent observations proved it to be steadily growing, 
and after some months had attained a height of over 
1000 feet. Professor Heilprin noted a growth of about 
20 feet in four days. 

\'arious explosions and movements of the earth altered 
the relative height of the obelisk. It rose and fell and 
large portions became detached. Bit by bit it then 
receded again, sinking as much as 150 feet during one 
night, but frequently rising again temporarily. This 
continued during many months, till finally it disappeared 
within the cone. 

The cause of this curious apparition can but be vaguely 
surmised. It has been suggested that the vent of the 
volcano in olden days had become filled with solidified 
lava, and when the first outbreak occurred this whole 
mass was raised bodily up, as a cork is forced upward 
from a bottle. 



■ K'iowie.l;f .'- S. iV itr/i.- .Vft,s." 



^^ 





The Obelisk of Morvt Pelee. 



Mar., 1904.] 



KNOWLEDGE cS: SCIENTIFIC NEWS. 



39 



The Face of the Sky for 
MarcK. 

By \\. Shackleton, F.K.A.S. 



The Si'N. — On the ist the Sun rises at 6.4S, and sets 
at 5.3S: on the 31st he rises at 5.4.1, and sets at 6.2q. 

The vernal equinox occurs on the 21st, when the Sun 
enters the Sign of Aries at i a.m. and Spring commences. 

Sunspots may frequently be observed, and for plotting 
their posiiions the following table may be used. 



Date. 



Mar. I 

.. II 
.. 21 
.. 31 



Axis inclined to \V. from 
N. point. 



21'' 48' 

24^ o' 

25° 31' 
26" 21' 



Centre of disc, S of 
Sun's equator. 



7' 14' 
7" 12' 
f>' 57' 
6 30' 



Date. 




Phases. 


Mar 2 .. 
.. ■• 
.. 17 •• 
., 24 .. 
.. 31 •• 




C 


Full Moon 
I^si Qnarier 
New .Moon 
First Quarter 
Full Moon 



II. M. 



2 48 a.m. 

I r am 

5 39 am 

9 37P-m- 

o 44 p.m. 



The Zodiacal light should be looked for in the west for 
a few hours after sunset. 
The Moo.v : — 



The Moon is in perigee on the 1st and 29th and in 
apogee on the 14111. 

Occulta-tions. 

The following 'are the more interesting occultations 
\-isible at Greenwich during convenient hours ; it will be 
seen that on the 22nd the Moon is in the Hyades : — 



Saturn is a morning star rising a little more than ,in 
hour before the sun. 

Uranus rises after midnight and is situated rather low 
down in the sky near the star 4 Sagittarii. 

Neptune, as will he seen on reference to the chart in the 
January number, is about midway and 10' south of the 
line joining the stars v and u Geminorum. 

Telescopic Objects: — 

Double Stars. — y Leonis, X.'' 14'", N. 20' 22', mags. 2, 
4; separation 3"-8. In stead\'air, the prime reciuisite for 
double star observations, tliis double inav he well feen in 
a 3-in. telescope with an eyepiece magnifying about 30 to 
the inch of aperture, hut on most nights one with a 
power of 40 is better. 

The brighter component is of a bright orange tint, 
whilst the fainter is more yellow. 

1 Leonis, XI.'' 19'", N. 115', mags. 4^, 7A ; separa- 
tion 2"-2. A pretty double of different coloured stars 
the brighter being yellow, the other blue. This object 
requires a favourable night and a fairly high power on 
small telescopes. 

a Leonis {I\ff;iiliis) has a small attem'ant about i ScV 
distant, and of the >^'5 magnitude, and easily seen in a 
3-inch telescope. 

u. Canum X'enat. (Co;- Cai'oli), XII.'' 52", N. 38' 50', 
mags. 2-5, 6-5, separation 20" ; easy double, can be seen 
with moderately low powers, even in 2-in. telescopes. 

Meteor Showers : — • 





Radiant. 




Date. 


R.A. 


'Dec. 


Near to. 

T Leonis 
f( Draconis 
ii Ursae 
f Draconis 


Characteristics. 


Mar. 1-4 
„ 14 
.. 24 
., 28- 


h m. 

II 4 
16 40 

16 44 

17 32 


4- 4 
4- 54 
+ 58^' 
4- 62° 


Slow; bright. 
Swift. 
Swift. 
Rather swift. 



The Stars. — About the middle of the month at 9 p.m. 
the positions of the principal constellations are as follows : 



Disappearance. 



Reappearance. 



Date. 



Star's 
Name. 



Magni- 
tude. 



.Vngle from .^ngle from 

Mean Time. Mean Time. 

\. point \'ertex N. point Vertex 



March 


22 




22 






22 . 






22 . 




, 


23 ■ 




, 


25 



e' Tauri 
75 Tauri 
D.M. 4- 
B.A.C. 1391 
1 1 T Tauri . . 



ij 



fi33 




10.41 p.m. 
10,35 P "1- 
II. I p m. 
11.39 p.m. 
I ! . I p.m. 
10. II p m. 



223 

324' 
270 

274 
293 

272" 



184° 
28.5 
232 
238 

252'' 
236 



Moon's 
Age. 



\(< 
If) 
ifi 

17 
16 

15 



The Planets. — ^lercury is in superior conjunction 
with the Sun on the 26th, and throughout the month is 
too near the Sun for observation. 

Venus is an inconspicucus morning star during the 
month ; also, as she only precedes sunrise by about an 
hour, she is badly placed for observation, and is becom- 
ing more unfavourably situated as she is approaching 
conjunction with the Sun. 

Mars sets about 2 hours after the Sun on the ist, 
and about i^ hours on the 31st ; on account of his small 
angular diameter, he is an insignificant object in the 
western sky shortly after sunset. 

Jupiter is in conjunction with the Sun on the 27th, 
and therefore is only visible during the early part of the 
month after sunset. 



Ze.mth . No bright constellations in the zenith. 

South . Cancer and Hydra on the meridian ; 
Gemini high up, Procyon and Siriiis, all a litlle to 
the \y. Orion is to the S.W., and Leo (AVi';////s) 
to the S.E. high-up. 

West . Taurus, Aries near setting, Auriga 
{CapcUa) high up. To the N.W. Perseus, also 
Andromeda low down. 

East . N'irgo (Spied rising), Bootes (Anttirus). 

To the N.L. I'rsa .Major liigh up, (^orcjna, Her- 
cules, and Vega low down. 

North . /Wfov's ; to the right, Ursa Minor, Draco; 
below, Cygnus, Cepheus ; to the left, Cassiopeia. 

Minima of Algol inay be observed on the i'')th at 
o h. 7 m. a.m., i8th at 8.56 p.m., and 21st at 5.45 p.m. 



40 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



A Photographic Atlas 
of the Moorv. 



VoLiMi; LI. of the Annals of the Harvard College Observa- 
tory is devoted to a photographic atlas of the Moon. This 
marks an epoch in selenography, not only because it is the 
first complete photographic atlas of the Moon yet pulilished, 
but because every part of the Moon is represented under five 
different conditions of illumination — sunrise, morning, noon, 
evening, and sunset. This fivefold presentation is of the 
greatest importance to the selenographical observer, as the 
change in appearance of most of the lunar formations during 
the course of the lunar day is so great that a photograph 
taken at one time becomes almost unrecognisable if compared 
with the Moon at another. It constitutes a record in another 
particular, namely, that the entire series of photographs were 
taken within the short period of seven months. Yet a third 
feature of the atlas lies in that this was the first time that a 
long focus telescope has been successfully employed in this 
department of astronomy. Such telescopes ha\e been em- 
ployed with success upon the corona in recent eclipses, but 
their application to the systematic record of the Moon was a 
new departure. 

This work is the result of one of those enterprises which the 
measureless energy of Prof. E. C. Pickering, and the corre- 
sponding munificence of the American public, have brought 
to completion within the last few years. An expedition under 
Prof. \V. H. Pickering, who has had much experience of the 
superb observing conditions both of .-Xrequipa and Arizona, 
was sent out from Har\ard College to the Island of Jamaica, 
and reported so satisfactorily on the " seeing," that at the end 
of 1900 he took out there a photographic O.G. of i^-inches 
aperture, and 135 ft. 4 in. focal length. This was set up at 
Mandeville, 20M0 feet abo\e the sea level, and used as a fixed 
telescope in conjunction with a heliostat. The seeing did not 
prove to be quite equal to expectation, and a yet more serious 
drawback was experienced in the want of flatness of the 
heliostat mirror. In most cases, therefore, the aperture of the 
photographic telescope had to be diminished to 6 inches, and 
the exposures lengthened accordingly. 

From the photographs taken by the expedition, 80 were 
selected, each y in., by 4 in., to form the complete lunar atlas, 
the Moon being divided for the purpose into sixteen different 
regions, each shown, as noted above, under fi\e different con- 
ditions of illumination. The parallels and meridians were 
laid down on a photograph of the full Moon, taken on 1901, 
August 21), the positions derived by Franz from measures of 
five negatives of the full Moon take'n at the Lick Observatory 
being taken as standards. Professor Franz's positions are 
undoul)tedly the most accurate yet published, and Professor 
Pickering devotes the last chapter of his book to an inquiry 
as to whether the altitude of a lunar mountain can be deduced 
from the discordances between its apparent co-ordinates on 
the lunar surface, as measured under different conditions of 
libration. The result, howe\er, is not very encouraging, the 
displacement to be measured being very nearly of the same 
order as the errors of observation, as Mr. S. A. Saunder has 
recently pointed out," and a far more extensive series of 
me.isures than any yet published are required in order to 
satisfactorily solve the question of lunar altitudes. The third 
chapter is devoted to the consideration of lunar change ; the 
cases of Eratosthenes, Pliniiis, and Pallas being lightly alhided 
to, whilst Linne, Plato, and Messier, with its companion 
Messier A. are treated with considerable detail. The enlarge- 
ments of Plato and Messier, especially the former, by no means 
justify Professor Pickering's claim that " these are the first 
photographs published, so far as I am aware, showing the details 
of the floor so plainly th.it they may l>e clearly distinguished." 
They are certainly not equal to the photographs of Plato 
in MM. Loewy and Puiseux's .Atlas. Another point on which 
Professor Pickering lays himself open to some criticism is the 
uncompromising way in which he habitually speaks of bright 
spots on the Moon being "snow," or "hoar frost," or " ice " 



• Observatory, iyo.|, Fobni.iry, p. y6. 



whilst dark spots are often as unhesitatingly described as 
■• patches of vegetation." While not wishing to ignore the 
very considerable amount of evidence which Professor 
Pickering has elsewhere presented in favour of these, his 
views, they cannot yet be regarded as more than mere opinions, 
and it is hardly legitimate for him to express himself as if they 
were altogether beyond challenge. 

" Ann.'ils of the Astronomical Observatory of Harvard College," 
Vol. LL, a Photogr.iphic Atlas of the Moon, by William H. Pickering, 
Cambridge, Mass. Published by the Observatory, 1903. 

La>.rge v. Small Telescopes on 
Planets. 



To THK Editors ok " Knowledge." 

Sirs. — I was much interested in Mr. A. Stanley Williams's 
letter in the current number of " Knowledge." No doubt 
there is reason in his suggestion. But to my mind there is a 
much stronger reason for the greater relative defining power 
of small telescopes when used on planets over their perform- 
ance on double stars, which seems to be generally overlooked. 

( )n double stars, I Iielieve. the rule of 4-56 seconds of arc 
divided by the aperture is generally accepted as the limit of 
the telescope's di\'iding power, and this agrees very well with 
theory. But it only holds good when the objects to be sepa- 
rated are sufiiciently bright to cause strong interference 
effects. Now the details on a planet are seen against a back- 
ground nearly as bright, and except at the edges the contrast 
is ^•ery feeble, so interference phenomena .are less appreciable. 
Therefore I hold that the 4-56 seconds-over-aperture rule does 
not apply. Mr. .\. Stanley Williams, in his first paragraph, 
also seems to imply a doubt of ordinary rules holding for lari^c 
areas, but I maintain that small telescopes will separate details 
on a planet very much closer than the above rule would 
allow. And so would, and sometimes does, a comparatively 
large aperture, but the magnification needed to tone down the 
light to utilize the larger aperture needs better atmospheric 
conditions, so that it is comparatively rarely that such aper- 
tures can be used with full effect. If we take 40 diameters to 
the inch of aperture as about the best ratio for viewing, say. 
Mars, one will on most nights find the seeing good enough to 
use the 120 needed by a 3-inch. But apply that rule to the 
40-inch Verkes, and how often can a power of 1600 be 
employed to advantage ? 

A few years ago I made some experiments to test the sepa- 
rating power of I inch of aperture directed to black spots on 
white paper. I found that i inch would divide dots separated 
not more than i second of arc. and lines 07 second apart ; 
and that it would show a single black line o'S second in 
width, which was, of course, separating white areas divided 
by that amount only. I think these experiments, which 
can readily be repeated by anyone who wishes, show 
that when interference effects are negligible, one may expect 
a telescope to go far beyond the usually accepted limits. But 
if more were needed, Mr. and Mrs. Maunder have supplied it 
in the paper published last July in the B.A.-A. Journal 
alluded to by Mr. Williams in his letter to " Knowledge." 
There they show that a black line on unglazcd paper was seen 
sharply defined with the unaided eye under an angle of only 
2'S seconds of arc. Taking the pupil of the eye when fully 
dilated at the extreme of one quarter of an inch, this is 
equivalent to 07 second of arc for i inch, which agrees well 
with my own experiments detailed above, though I consider 
it much more noteworthy, as the retina is composed of hexa- 
gons that at the nodal point of the lens system 01 the eye 
subtend an angle of about 23 seconds of arc, and th.at such a 
coarse structure should show a line only 2'8 seconds wide as 
sharply defined seems to bear out what Mr. Maunder says in 
his last paragraph, that : " A straight line is that which gives 
the least total excitement in order to produce an appreciable 
impression, and therefore the smallest appreciable impression 
oroduces the eff'ect of a straight line." 

H. W.\KE. 

Whiteha\en, January 11, 1904. 



Mar., 1904.] 



KNOWLEDGE & SCIEXTIEIC NEWS. 



41 




ASTRONOMICAL. 



Mr. Denning's Observa.tions of Mars 
in 1903. 

In the Astroiu'iiiisilw S'liiliiichten, No. 3426, Mr. F. W. Demiiiig 
gives the main results of his observation of Mars with a lo-inch 
reflector, in the Spring of 1903. The powers that he used 
ranged from 252 to 4S8. but the one most commonly employed 
was 312. He noted that occasionally there were decided 
changes in the visible appearance of certain markings, and 
these changes were obviously not due, either to uncertain 
seeing, or to the varying inclination of Mars, but, in the 
observer's opinion, to local vagaries in the Martian atmosphere. 
Thus, on May 6 and 7, he saw a white band dividing the canal 
Nilus, not seen on March 31 or April 2, and not shown on the 
charts, .\gain, on May 21. the northern region of the Syrtis 
Major was very dark, with a white cloud on its southern edge, 
but on May 23 and 24 the whole Syrtis Major was very faint, 
as if veiled by the cloud spreading northwards. As regards 
the " canals," Mr. Denning says : " ,\ large number of 
irregular dusky streaks ^canals), different in tone and direction, 
were observed. Some of these were very distinct, as, for 
example, Nilosyrtis, Protonilus, Indus, Ganges. Cerberus, 
Casius, &c., while others, as Phison, Euphrates, Gehon, were 
feeble or extremely faint and delicate. Many of them were 
knotted or strongly condensed in places, and particularly so at 
those points where either a junction or intersection of two of 
them occurred." Mr. Denning considers these streaks as 
certainly objective. He says that they were single, though in 
a few instances two of them w-ere placed tolerably near to- 
gether, running in appro.ximately parallel directions. He is 
emphatic that the " prolific system of double canals delineated 
by some observers had no existence " during the period of 
observation, as far as his eye and telescope could determine. 
Comparing these recent observations with those made in 
February, i.S6g, Mr. Denning deduces from I2,ij6 rotations of 
Mars, the value 24 h. 37 m. 22-7 s. for the rotation period. 

The Double Carvals of Ma.rs. 

Mr. Lowell, in Bulletin No. 5 of bis Observatory, gives 
evidence against the hypothesis that the gemination of the 
Martian canals is an interference effect. If it were so, the 
width between the two components of a double canal should 
vary inversely as the aperture. To test this, Mr, Lowell ob- 
served a number of double canals with the full aperture of his 
telescope ^24 inches), and then with that aperture reduced to 
18, 12, and 6 inches. His measures of the drawings made 
under these several conditions showed that the apparent 
angular separation did not increase as the aperture was 
diminished ; that the separation was invariable within the 
limits of observation for any particular canal, but differed for 
different canals, bearing no relation to the width of an inter- 
ference pair of lines. 

Mr. Lowell's ObservaLtions of Ven\js 
in 1903. 

In Bulletin No. 6, Mr. Lowell classes the markings to 
be made out upon Venus under two heads. The first includes 
the collar round the south pole and the two spots on it, and 
the nicks inward from the terminator. Of these Mr. Lowell 
states he has ahvaysbeen certain, and "they alone are sufficient 
to show that the planet's rotation is an affair of about 225 
days." The second class include the long shadings from the 
centre of the disc to the terminator, and of these, also, Mr. 
Lowell asserts " the objectiveness beyond the possibility of 
illusion." It will be seen that in this assertion Mr. Lowell is 
withdrawing his withdrawal of these markings which he pub- 



lished some eighteen months ago in tlir Aslivnoniisclti' 
Xiichrichltii. No. 3.S23. Mr. Liiwell furtluT adds that these 
streaks "bear no resemblance whatever to the ' canals '. of 
Mars, They are faint streaks or spots. . . . Tlu-v .ire not 
of even width, are not dark, and shai^iicul,^ .^ , . I'urllier- 



more, they are of a much higher order ortlill^iMtv c;l'vul(i»jj,s 
the conditions of visibilitv arc such as to sliilWajo ohsersi-r iTuT 



'canals' of Mars with ease, 



^i.^o saowajo^kse . 
aiuty, it wcreliSfTess to 



attempt this much harder plaiic*'.* Vjl-!ijt'il6^i^|}37s,WW' Lowuli 
Bulletin ch- la Socictc'^:\str,mnn,,,,ur^}»l l-i>mflU: 



etle^ 

ly 



wrote in the 

" Lcs configurations out tonjours dJiHrt ■^ 
en veritc que celles de la Lune. ' In 
for December, 1S96, lie wrote ; " The markiii,L;r. .nr iHuiniisi 
and well defined ; their contours standing out sharply against 
the lighter parts of the disc. . . . The seeing must l)e dis- 
tinctly bad to have the more prominent among them not discer- 
nible." This would seem to show that the definition at Flagstaff. 
Arizona, has changed seriously for tiie worse in the last seven 
years, whilst a comparison of the drawings of Venus, given in 
ttie Bulletin, with those of M.ars, such as in I'opitli::- 
.Istroitiiiny for y\pril. iiS()5, would not lead to the conclusion 
that there was any essential difference lietwcen tlie streaks on 
the two planets. 

Calcium and Hydrogen Floccxili. 

A memoir of quite exceptional interest is given on the 
subject by Professor G. F. Hale and Mr. Ellerman in Volum. 
III., Part I., of the Puhlutilioiis vf the Yirkcs Observatory 
Its subject is the minuter study of the surface of the sun by 
means of the spectroheliograph. The first point brought out 
is the essentially granular structure of the calcium fiocculi, 
the entire surface of the sun showing a fine mottling when 
photographed on the l)right K-hne, The next point is the 
study of these calcium clouds at difi'i-rent levels, the result of 
the examination bringing out in a striking manner the way in 
which the calcium bright clouds expand as they rise higher. 
The detection of the dark hydrogen fiocculi is another feature, 
and the fact that they often correspond, though not precisely, 
with the bright calcium fiocculi. Last of all the discovery of 
dark calcium fiocculi was established, and the necessity for 
further work with spectroheliographs of much higher disper- 
sion, and working upon larger images of the sun, is insisted 
upon. The memoir is illustrated by fifteen extremely fine 
photographic plates. 

The Nebulae. 

The Siiictccnth Century (iiui After for I'ebruar}' contains 
an article on " The Nel)ul;c," l>y the Rc\'. ICdnumd Ledger 
(iresham Lecturer on Astronomy, whicli summarises with 
admirafjle clearness and precision, the state of our present 
knowledge respecting these mysterious objects, and the con- 
nection with them of the stars. 

ZOOLOGICAL. 

At the meeting of the Geological .Society lield on January 20 
Dr. A. Smith Woodward, of the British Museum, definitely 
determined th(^ .systematic position of the cretaceous fishes of 
the genus I'tycliudus, whose large, quadrangular, ridged crush- 
ing teeth are such familiar objects to collectors in the chalk- 
pits of the south-east of England. It has long been known 
that I'lychudus was an elasmobranch fish, and Dr. Woodward 
himself had some years ago pointed out the probability of its 
being a ray, or skate, rather than a shark. The truth of this 
conclusion is fully demonstrated by a specimen of the jaw 
cartilages recently discovered near Lewes, which serve to show 
that these fishes were allied to both the eagle-rays and the 
sting-rays, and probably, therefore, the ancestral type of bolli. 
A photograph was shown at the meeting of a splendid .\mcri- 
can specimen of the dentition of Ptychudus, witfi the teeth in 
their natural position, forming longitudinal rows. 

* ;;■- 

Fossil Birds- 
Certain fossil bird reiriains were discussed by Dr. C. W. 
.Andrews at the meeting of the Zoological Society held on 



4^ 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



January ly. From Madagascar the speaker described a pelvis 
and thigh-hone of an ostrich-lil<e bird closely allied to the ex- 
tinct roc LJipyoniis) of that island, but regarded as generically 
distinct, under the name of Mullcyoritis.. Much greater interest 
attached to a fragment of another bird of the same group from 
the Eocene strata of the Fayum district of Egypt, for which 
the name F.nmuiiiis was suggested. Possibly the discovery of 
this specimen might serve to demonstrate that all the ratitc 
birds ha\e a common ancestry, and are not. as some suppose, 
isol.ited members of a number of distinct groups which have 
lost the power of flight independently of one another. 

A Sub Species of Gira.ffe. 

M the meeting of the abo\ e-named Society, on February 2, 
the local sub-species of girafl'e formed the subject of a com- 
numication by Mr. Lydekker. It was shown that, as in the 
case of the boute-quagga, or BurchoU's ;;ebra, a number of 
local forms readily distinguishable by their colour and mark- 
ings, and (in the case of the giraffe) to some extent also by 
difterences in the skull, are recognisable as we proceed from 
north to south down the eastern side of the Continent. In 
both instances it seems advisable to regard their local forms 
as races, or sub-species, rather than species. The northern 
tonus are characterised by the presence of a large frontal horn 
and the white legs; but, as we proceed south, the median 
horn gradually becomes reduced to a mere boss, while the 
legs aci|nire spots right down to the hoofs. In the latter 
respect giraffes show a modification, exactly the opposite of 
that presented by the boute-quaggas, in which the legs lose 
their stripes as we proceed south. Some of the East African 
giraffes are very remarkable, developing, in certain instances, 
rudimentary horns on the occiput, or o\er one eye, or dis- 
playing a marked sexual difference in colour. A race from 
the south of Lada was named in honour of Major Powell- 
Cotton, the celebrated explorer, and a second, from the 
Northern Tranb\aal, after Mr. Rowland Ward, of Piccadilly. 

Ca.chalot Whales. 

In the I'lilil of January j reference is made to the occurrence 
ol (juite a number of sperm-whales, or cachalots, in the North 
Sea and North Atlantic ; no less than se\en adult bulls lieing 
definitely known to have been captured. As a rule, these 
whales are confined to tropical and subtropical seas, only a 
few old bulls occasionally straggling northwards. In the pre- 
sent instance a whole herd must have thus wandered out of 
the proper latitude. Recently Sir William Turner has re- 
corded the capture of an old bull in the Shetlands in igoi, 
also mentioning that a herd was seen off the Faroes in iSyy; 
while in the Field of January jO Mr. T. Southwell refers to 
accounts of herds of these whales straying northwards in 1723 
and 1752-53. 

The Primeval Instincts. 

A discussion has been going on in the columns of the Field as 
to the reason why horses when getting up from the recumbent 
posture raise themsehes first on the fore-limbs while ruminants 
do so on the hind-limbs. It appears that tapirs, apparently 
rhinoceroses, and swine follow the horse-fashion ; an associa- 
tion which demonstrates that the movement is not dependent 
on the presence of a third trochanter on the fenmr of the 
Perissodactyla (hor.ses, tapirs, and rhinoceroses). One writer 
has suggested that the ruminants' mode of rising is for the pur- 
pose of bringing the horns into action for defence as soon as 
possible, but against this is the case of the rhinoceroses. 
I'ossil;ly the raising of the hind-legs first may be connected 
with the function of rumination and the complex form of 
stomach correlated therewith. One correspondent stated, 
however, that an ass rises like a ruminant, which, if true, upsets 
all theories. 

New Ma.mmals. 

An instance of the pace .it which .Vmerican naturalists are 
increasing zoological nomenclature is atlorded bv a paper by 
Dr. 1). G. Elliot recently published by the Field Columbian 
Museum of Chicago, in which no less than twenty-seven ap- 
parently new forms of manunals arc described. Hitherto 
there has been supposed to be only a single species of glutton, 
ur wolverine, but tlie author describes the .\laskan represen- 



tative of that animal as new, under the name of i;ulo lutcus. 
A new race of bighorn sheep {Ovis caiunlcnsis cremnobates) is 
also recorded from the San Pedro Martir Mountains of Lower 
California and Mexico. 

Bird Migration. 

Mr. W. Eagle Clarke, who is well known as an authority on 
the subject of the migration of birds, made a month's stay last 
autunm on the Kentish Knock Lightship, and the results of 
his \aluable observations are detailed by him in the Ihit,. It 
recpiired a good deal of courage to brave the hardships and 
discomforts inseparable with life on a lightship 21 miles from 
the nearest point of land, but Mr. Clarke was so engrossed 
with watching the birds which passed the ship by day and 
were lured to its light by night that he seems to have hardly 
noticed the discomforts involved, .'\part from the valuable 
details regarding the various species of birds migrating and 
the directions in which they were travelling, as well as many 
other points which we have not space here to discuss, Mr. 
Clarke makes some remarks of high importance with regard 
to some of the phenomena of general interest connected with 
bird migration. As an explanation of how birds find their way 
during migration it has been suggested that the great height 
at which they fiy enables them to see enormous distances. 
But Mr. Clarke, while not denying that birds sometimes do 
migrate at great elevations, disposes of the theory that they 
depend on this means for finding their way. During all the 
time he was on the Kentish Knock Lightshii) the migrants of 
every species flew close to the water. Vet whatever the 
weather or state of the sea they kept a straight and apparently 
unerring course for the coast 21 miles distant. Mr. Clarke 
reaches the conclusion from this and other facts that liirds are 
endowed with a sense of direction. Such a statement is, of 
course, in no way an explanation of the mystery as to how 
birds find their way, since we have no conception of the 
nature or workings of such a "sense." But the evidence that 
they do not find their way by sight is of the utmost import- 
ance. Those interested in bird-migration should not fail to 
read Mr. Clarke's latest and very valuable contribution to our 
knowledge of the subject. 

Burrowing Fishes. 

In h'lihiiiitli MiiLiwnsis.a. publication devoted to the descrip- 
tion of the results of a recent expedition to the Malay Penin- 
sula, a writer records a remarkable habit on a part of one 
species of the nuid-haunting fishes of the genus Pcriophthalmui. 
These fishes make burrows in the nmd, and retain a pool 
above the same, by preventing the water from flowing away 
during low fide by means of a circular well built by them- 
selves. 

One of the most remarkable paheontological discoveries is 
recorded from North .America, where an Eocene lemur is 
believed to be allied to the curious aye-aye iChii'omys) of 
Madagascar. The extinct form is named Parihtiiroinys. 

Papers Rea.d. 

In addition to those already mentioned in special para- 
graphs, reference may be made to the following zoological 
papers read at various scientific societies. .At the Linntean 
on December 17, Mr. H. J. Fleure discussed the origin and 
evolution of the gastropod molluscs known as Ducogloisa, of 
which the limpet is a famiUar example. At the same Society 
on Jamiary 21, the Rev. T. R. R. Stebbing read a paper on 
the Crustacea obtained during surface dredgitig from H.M.S. 
lifsearcli, in the Bay of Biscay, during the sunnner of ii)00. 
On January ly, before the Zoological Society, Mr. O. Thomas 
described a new subspecies of the aoul(<;((;i7/((ii(i-»;H;t' /•/»!,';) from 
North-East Africa. At the same time Mr. G. A. K. Marshall 
presented a monograph of the beetles of the genus IlippurliiHUi. 
Dr. W. Kidd called attention to the importance of the arrange- 
ment of the hair and the distribution of hair whorls in the 
classification of mammals. Dr. W. G. Kidewood described 
the skull of the giraffe, as seen in vertical transverse sections ; 
and Mr. F. E. Beddard read a note on the brain of two lemurs. 
At the meeting of the same Society on February 2, in addition 
to Mr. Lydekker's paper on girartes, a communication was 
received from Mr. tX Thomas on a collection of mammals 
from .Namaqualand, including a new species of strand-mole 



Mar,, 1904.] 



KX0\\L1:DGK c^ SCIl'NTIFIC NEWS. 



43 



{Baihi/irgiis); and Mr. Bedd.ird discoursed on the arteries of 
the base of the brain in certain nuunnials. Two papers by 
Mr. G. .A. Boulen,t;er were also taken at the same nieetinf;, the 
one dealing with throe new fishes from the Niger, and the 
other with the type L-pecimen of the West African catfish 
known as Clariiis /<i;'iiv/is. Ai the meeting of the same 
Society, held on February 16, Mr. C. Crossland presented the 
third instalment of a dissertation on the marine fauna of 
Zanzibar and British ICast .Vfrica, dealing in this instance 
with the polychietous annelids : and also a second paper 
describing a collection of the same group of organisms from 
the Mahay Peninsula. The third paper, by Sir C. l-.liot, dealt 
with certain nudibranchiate molluscs from '/Cannhav and 
British East Africa. 

A New GaLzelle from the White Nile. 

Considerable iiUerest attaches to the description by the 
Hon. Walter Kothschild, in .W; iVii/tv /<i(ilof;iCiC, of a fine new 
species of gazelle from the banks of the White Nile, which it is 
proposed to call Giiztllii alhoiiotalti. 



BOTANICAL. 



HhKK LiNUEMi Til, of Bcrliii, has published in Cirtaitiora, 
1903, Heft iS and 23, the results of his experiments on the 
propagation of plants by means of their leaves. Horticul- 
turists have long been accustomed to use this means of pro- 
pagation in a few plants, notably in the Gluxinia and certain 
Crassulaces, among which Bryuphylluin calycinuin is a well- 
known example. It was, however, probably not suspected 
that the leaves of so many plants could be made to produce 
roots. In his first communication Herr Lindemuth gives the 
names of twenty-eight species, of nearl)' as many different 
genera, in which his experiments have been successful. These 
include such plants as the Foxglove {Digitalis purpurea), the 
Musk [Miinulus moschatus), the Tomato, and the Vine. The 
leaves of thirteen species, including the Potato, Monkshood 
(Aconilum Xapcllus), and the common bedding Geranium 
{Pelargonium zoitaU) refused to root at all. Usually the roots 
were produced quickly — in the Vine in sixteen days, in 
Veronica in seven days, and in the African Marigold in eight 
days — but the amount of time required, and, indeed, success 
at all, was shown to depend very much on the season when 
the experiments were made. Thus, in the Vine, roots were 
developed in sixteen days in .August ; but complete failure 
resulted in September, when the leaves perished. In his 
second communication, the author records success with thirty- 
four additional species, including three of those with which he 
had met with failure before. The results so far obtained shovv 
that few of the leaves thus experimented on will form buds, 
only five having done so. In the case of a species of Citrus, 
the leaves rooted and persisted for months and even years 
without any further development. — S. A. S. 

Recent Research in Agricuhure- 

Mr. Hall, the Director of the Rothamsted i:xperimcntal 
Farm, lecturing at the Royal Institution on " Recent Research 
in Agriculture," dealt with the growth of wheat, still an impor- 
tant crop in Great Britain, despite the fact that the area under 
wheat has shrunk from more than four million acres in i860 
to less than i,.Soo,ooo at the present time, and that we only 
now produced about seven million quarters, and had to im- 
port more than 25 million (luarters. The English yield 
averaged, however, more than ji bushels per acre, consider- 
ably greater than that of any other country, and double or 
treble that of the chief countries who send us wheat. The 
lecturer then showed, by examples drawn from the Rotham- 
sted experiments, that the production of wheat could be 
greatly raised by the use of manures, but that this process 
soon ceased to be profitable—"' high farming is no cure for low 
prices." A further difficulty to be faced by the English wheat 
grower is the comparatively low price of this product, the best 
Manitoba or Russian or Argentine wheat realising 20 to 25 per 



cent, more than the best English wheat. This dillereiicc of 
price is due to the greater '• strength " of the flour made from 
such foreign wheats, meaning by " strength " the capacity to 
make more and larger loaves for equal weights of lloiir used. 
The lecturer illustrated tlie point by exhibiting loaves baked 
from eijual weights of luiglish and .American llour, the 
.\niorican one being decidedly larger ;iiid more attractive in 
appearance. For some time the lecturer had been concerned 
with ;in en(|uiry initiated by the National .Association ol 
Millers, and helped by the Board of .\griciilture, as to the con- 
ditions which brought about " strength " in flour, and how 
ICnglish wheat could be impro\ed in this respect. Climate 
being one of the chief factors, the lecturer contrasted the 
ICnglish climate with thai of the Hungarian Plain and of the 
North West. The development of wheat, the r.ite of forma- 
tion of the grain, and the migration of the nitrogenous con- 
stituents into the grain was then studied at Rothamsted, and 
compared with similar results obtained in Hungary ; all tend- 
ing to show that strength is associated with a short period of 
ripening. Strength is dependent on the nitrogenous content ol 
the wheat, but the attempts to correlate it more exactly with 
total nitrogen, with gluten, or with the ratio between gli.adin 
.uid glutenin, as certain French and .American chemists have 
done, fail to show consistent results. Climate is not, however, 
everything in causing strength, for even among b^nglish 
wheats some are much strongc'r tlian others. Certain 
foreign varieties also when introduced into this country retain 
to a very considerable degree their strength, at any rate for 
three or four years. However, they generally give crops con- 
siderably below the English stand.ird, though for late spring 
sowing some of the best, like No. i Hard Manitoba, .are prob- 
ably ecjual to .any lingllsh varieties. As "strength" is a 
(|uality inherent in the variety, it is capable of improvement 
by cross-breeding .and selection, and a considerable amount of 
% ery promising work has idready been done in this direction, 
the disideralum being increased strength with the cropping 
powers of the best I-Inglish varieties. The lecturer exhibited 
various loaves made from English and foreign varieties of 
wheat grown in this country to illustrate the foregoing points. 



PHYSICAL. 



Photography in Natura.! Colours. 

Thl principal novelty of a process lor obtaining photographs 
with natural colours, just brought out in Berlin, is the fact 
that any ordinary negative may be made to give chromatic 
prints with the original colours. Suppose a view of a lands- 
cape to be taken with an ordinary plate; the sky being blue, 
will throw on the plate the most efficient light, so as to pro- 
duce on the negative the thickest dark layers. The leaves of 
the trees, on the other hand, will produce less intense effects, 
and still less will be the action of the red portions. Now the 
in\ entor, Oberleutnant von Slawik, .an .Austrian, has designed 
a special kind of pigment paper, bearing a nuinber of super- 
posed dye-stull layers ; underneath there is a red layer, in the 
middle a green, and above a blue layer. Now the most 
strongly C(jvercd portions of the negative -representing the 
sky — will evidently be the least translucent, the light actually 
penetrating being able to act only on the upper blue layer, 
rendering insoluble only the chromium jelly constituting this 
layer. The thinnest portion of the negative, corresponding 
for instance to a red wall, will in printing transmit the 
greatest amount of light ; all three pigment layers thus being 
struck l)y the light will become insoluble down to the loA-est 
red layer. The green leaves will, as above shown, give rise 
to a covering of the plate of medium intensity, a medium 
amount of light penetrating the paper at the corresponding 
portions of the plate, this amount of light being just sufficient 
to render insoluble the two upper blue and green strata, 
whereas the lowest layer will remain unaltered. 

.After printing, the paper, as usual, is pressed on another 
sheet of paper, when the coloured layers are transferred from 
one sheet to the other, the printing being afterwards "deve- 
loped " with warm water, in the way usual in pigment printing 



44 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



After the transferrins the low layers of the original paper 
will in the new paper be uppermost. The warm water will, 
therefore, be able to rinse off any jelly layers which have 
not become insoluble by the effect of light. On the portions 
corresponding to the sky, the green and red layers which are 
not struck by light will be removed, the blue layer only 
remaining. In the red wall, where the light as above shown 
has penetrated all the existing layers down to the lowest red 
layer, which, after the transferring is above all the remaining, 
no alteration will be produced, while in the portions corre- 
sponding to the green leaves only the red layer, which 
now covers the green colour, will be washed off by 
the water, when the green colour becomes visible, covering 
the blue layer lying underneath. In practice, it has been 
found advisable to use a larger number of coloured 
layers instead of those corresponding to the three funda- 
mental colours only, so as to produce all the shades required ; 
up to 14 pigments are thus used. The abo\e process has 
been developed in the laboratory of Dr. Ad. Hesekiel 
and Co., Berlin. .As a matter of course, any old negati\-es 
taken at any time may be made to reproduce the true colours 
of the original. — A. G. 

The Blondlot or N-Rays 

In view of the interest which has been imparted to M. Blond- 
lot's X-rays by the investigations of Professor Charpentier, 
and also by the doubts which ha\e been thrown on the real 
existence of the rays, we have thought that it might be inter- 
esting to collect the ascertained facts and observations con- 
cerning these rays. For this summary we are chiefly indebted 
to a series of articles contributed 'by Mons. La\ erune to 
Casinos. 

The X-rays were discovered bv M. Blondlot, of Xancv. 
while studying Rontgen rays. By endeavouring to pass rays 
through a sheet of aluminium, he separated quite a new group 
of radiations. The rays he found were such as to penetrate 
alumunum. black paper, or wood. They could be polarised 
and might be deflected or diffused, but they produced neither 
fluorescence nor photographic action. They were invisible, 
gave no sensation of light, but augmented the brilliancy of an 
electric spark. 

It is this property which enables us to detect the ravs. They 
are incapable of exciting phosphorescence in bodies which caii 
ac(imre this property from the action of light ; but when such 
a body, sulphuret of calcium for instance, has first been ren- 
dered phosphorescent by exposure to light, then if submitted 
to the action of these rays, especially if they are focussed bv 
a quartz lens, one can see the brightness of the phosphor- 
escense perceptibly increase. In the same way if one directs 
them on to a little flame of gas at the end of a metal tube 
pierced by a very minute orifice this flame, entirely blue, 
becomes whiter and more luminous. We are now furnished 
with these means of detecting the presence of these radiations. 
M. Blondlot, struck with certain analogies that they present 
with the radiations discovered by Professor Rubens in the 
emissions of the Auer Burner, asked himself if the X-rays 
were not identical. An Auer burner .was enclosed in a kind 
ot Lantern of sheet iron closed at all points, with the exception 
ol the openings for the escape of air and the gas from com- 
bustion, and so arranged as to prevent the passage of any 
light. A rectangular window opened in the iron at the light of 
the incandescent mantle was closed bv an aluminium sheet 
I mm. in thickness. The chimney of" the Auer burner is of 
sheet-iron. A slit was opened opposite the mantle, so that 
the luminous rays which emanate from it might be directed 
on to the aluminium sheet. Outside the lantern in front of 

he alummmm sheet was placed a biconvex lens of quartz, and 
behind It an exciter giving little sparks. It was ascertained 
that the spark is of greater or less clearness according to 
the distance at which it is placed from the slit. M. Blondlot 
proved the existence of four distinct kinds of radiations. 
\V hen one directs a pencil of these rays either on to an 
electric spark, or on to a little flame, or a phosphorescent 
•substance previously exposed to light, one can see the li<'ht 
emitted by these different sources increase in brilliancy 



The greater number of artificial sources of light and heat 
emit X-rays. The sun emits them, as the following experi- 
ment shows : A completely dark and closed room has a 
window exposed to the sun, this window is shut by inside 
oak shutters, 15 millimetres in thickness. Behind one of 
these shutters, at a distance of i metre, is placed a tube of 
fine glass, containing a phosphorescent substance of sulphu- 
ret of calcium for example, previously slightly insulated. If 
now in the trajectory of the sun's rays, which are supposed to 
reach the tube through the wood, there is interposed a piece 
of lead, or even simply the hand, even at a considerable 
distance from the tube, the brightness of the phospho- 
rescence diminishes. If one takes away the obstacle it re-ap- 
pears. The interposition between the shutter and the tube 
of several sheets of aluminium, of cardboard, of a piece of oak 
three centimetres thick, does not prevent the phenomenon 
from taking place. All possibility of heat radiation, properly 
so called, is therefore excluded from hypothesis. 

Certain substances appear to have the power of storing up 
X-rays, and afterwards emitting them ; but the rays appear to 
penetrate a metallic mass, in this sense, very slowly. Thus, 
if one side of a sheet of lead two millimetres thick has been 
exposed to X-rays for some minutes, that side only has become 
acti\e. An exposure of several hours is necessary for the 
activity to reach the other side. .-Muminium wood, dry or 
moist paper, paraffin have not the property of storing up 
X-rays. Sulphuret of calcium has it. Having enclosed a 
dozen grammes of this sulphuret in an envelope, and then 
having exposed the envelope to X-rays, M. Blandlot proved 
that its neighbourhood sufficed to reinforce the phospho- 
rescence of a little lamp of sulphuret previously exposed to 
light. This property explains why the increase of the phos- 
phorescence of the action of X-rays takes an appreciable 
time both to be produced and to disappear. Owing, in fact, 
to the storing up of the X-rays, the different portions of a lump 
of sulphuret mutually augment their phosphorescence, the 
storing up is progressive, the store is not instantly exhausted, 
so that when one directs the X-rays on to the phospho- 
rescent sulphuret their effect slowly increases, and when they 
are suppressed their effect is only gradually extinguished. 
Following on the experiments made by M. Charpentier on 
the emission of X-rays, experiments to which we shall return, 
M. Blondlot conceived the idea that certain bodies might ac- 
quire the property of emitting rays from compression. He 
proved that pieces of wood, of glass, of indiarubber com- 
pressed by means of a carpenter's vice, become, during the 
compression sources of X-rays. 

Bodies which are themselves in a state of forced equilibrium, 
or molecular strain, as tempered steel or hammered brass, are 
spontaneous and permanent sources of X-rays. One can show 
it by means of tlie phosphorescent screen, and by another in- 
direct method — that of the increased action of a pencil of light 
upon the eye when it is accompanied by X-rays. 

The shutters of the laboratorj- are almost closed, and the 
face of the clock fixed to the wall sufficiently lighted for it to 
appear faintly as an indeterminate grey stain upon the wall at 
a distance of four yards. If the observer, without changing his 
place, directs towards his eyes the N-rays emitted by a brick 
or pebble, previously insulated, he sees the face whiten, distin- 
guishes clearly its circular shape, and may e\en succeed in 
seeing the hands. When the X-rays are suppressed the face 
again darkens. Xeither the production nor the cessation of 
the phenomenon are instantaneous. 

.\s in these experiments the luminous object is placed very 
far from the .source of the X-rays, and as besides, in order that 
the experiment should succeed, it is necessary that the rays 
should be directed not towards this object, but towards the 
e)-e, it follows that there is no question here of an increase of 
the emission from a luminous body under the influence of X- 
rays, but rather of the reinforcement of the action received by 
the eye, which is due to the X-rays which are joined to the 
rays of light. One can replace the brick by a sheet of 
tempered steel. 

The energy that the emission of X-rays represents is 
probably borrowed from the potential energy which corres- 
ponds to the forced state of tempered steel. This expenditure 
is doubtless extremely feeble, since the effects of the X-rays 
themselves are so, and thus explains the apparently illimit- 
able duration of the emission. A sheet of iron that is bent 
so as to take a permanent deformation emits N-rays, but 



Mar., 1904.] 



KXOWI.KDGF. .'V SCIENTIFIC NEWS. 



45 



the emission ceases at the end of some minutes. A block of 
aluminium struck with a hammer does the same, but the 
duration of emission is much shorter. In these two cases 
the molecular constraint is temporary, and the emission of 
N-rays also. Torsion produces analogous results to com- 
pression. 

Professor .V. Charpentier's investigations of N-rays are 
second in importance only to those of their discoverer. He 
sought for the radiation of N-rays chiefly with the aid of phos- 
phorescent screens of sulphuret of calcinm. but found that 
screens coated with platinocyanide of barium, whose fluores- 
cent intensity he rejjulated. with the aid of a salt of radium, 
covered with black paper, would give more satisfactory results. 
By these two processes of research, he discovered that N-rays 
can have several other origins than those of the sources of 
light indicated by M. Blondlot. He recognised that the little 
phosphorescent or fluorescent object increased in luminous 
mtensity, when it was brought near the body. Moreover this 
augmentation is more considerable in the neighbourhood of a 
muscle, and so much the greater as the muscle is strongly 
contracted. The same thing occurs in the neighbourhood ot 
a nerve, or of a nervous centre, where the effect increases witli 
the degree of activity of the nerve or of the nerve centre. By 
this means, in spite of the delicacy of the observation, one can 
recognise the presence of a superficial nerve, and follow it. 
These effects are not only observed by contact with the skin. 
they are perceptible at a distance. They are transmitted 
through substances transparent to N-rays (aluminium, paper, 
glass, &c.), and stopped by the interposition of substances. 
which are opaque to the same rays, lead (incompletely) or wet 
paper. They are not due to an increase of temperature in 
the neighbourhood of the skin, for they continue if several 
sheets of aluminium are interposed, or of cardbo.ard separated 
by layers of air and forming a calorific screen. These rays 
are reflected and refracted like N-rays. 

M. Charpentier has produced foci, manifested by the maxima 
of brightening by the aid of convergent glass lenses. The 
position of these foci, or maxima, although difficult to 
exactly determine, permitted recognition of the fact that the 
indication of refraction of rays emitted by the body was at 
least of the class and size of that determined by M. Blondlot for 
N-rays. It might be asked if the human body really emitted 
these rays, or if it only stored them up during the day or in 
the Ught, in the same way as the insulated bodies studied by M. 
Blondlot. After a sojourn of nine hours in complete darkness 
the phenomena were the same, and were still more easy of 
observation, because of the more perfect adaptation of the 
eye. The nerves and nervous centres, when they are the seat of 
an excitation, emit the rays in greater abundance. Charpentier 
has been able to determine the area of the heart ; he has also 
been able to follow the trajectory of a superficial nerve ; he 
has been able to recognise the topography by certain psycho- 
motor zones in the cerebral surface. He has seen in fact, that 
if the subject of the experiment happens to speak, the de- 
tective screen, when advanced at the same moment towards 
the region of the cranium which corresponds to the zone of 
articulate language, at the level of the left frontal convolutions, 
is more brightly illumined than when he kept silence. The 
researches of Charpentier suggest that the radiations called 
N-rays are not all alike, but must in reahty result from an 
assemblage of radiations of attributes as diverse as their origin 
some being emitted especially by the elements of the nervous 
tissues, and others by those of the muscular tissues. This 
theory is in accord with the physical observations of M. Bond- 
lot. Experiments already dating from several months have in 
fact shown to this eminent physician that the bundles of N- 
rays broken up by a prism spread themselves into a sort of 
spectnim, which establishes beyond proof that all the broken 
rays — rays whose wave length, incomparably smaller than 
that of light rays — are unequally refrangible, and conse- 
quently possess each individual attributes. The wave length 
has been recently determined as not greater than S micro- 
millimetres — about the one millionth of a centimetre. 

We have received from Mr. H. J. (ilaisher a copy of his 
March catalogue of ■■ remainders," which we notice contains 
many valuable and useful volumes in zoology, botany, and 
the various other branches of natural and applied science. 



The Super-Solid. 

Hints towards a Conception of the 
4th Dirrvervsion. 



I!y C. E. Bi;nham. 
Sp.i^cE, as we conceive it, comprises length, breadtli, and 
thickness, and it is hardly possible to imagine a fourth 
direction which is none of these. Further than that, our 
minds are so constituted that we seem to see that such a 
n w direction could not be. When we have traversed 
any material substance longitudinally, and across, and up 
and dov.n we appear to ha\e traversed it exhaus- 
tively. There is no direction which is not one of these - 
or, as we might say, there could be no direction which is 
not one of these three or intermediate between them. 
This is so as to all material substance, and that it is so 
as to space in the abstract we feel equally convinced, 
because by space we mean nothing else but the length, 
breadth, and thickness which matter occupies or might 
occupy. 

Yet, as everv appreciative reader of Abbott's Flatland 
knows, there is more to be said on this matter. Suppose 
a race of beings whose senses were such that they had 
never had any reason to suspect thickness as a property 
of matter, but were only conscious of length and lireadth, 
would it not appear to them that length and breadth 
filled all space, and that a third dimension was as im- 
possible as It was mconceivable ? 

Such a race of beings, conscious only of two dimen- 
sions, is indeed not unimaginable. Some have even 
theorised that a sightless snail, crawling from surface to 
surface, has no concept of any third dimension, but 
exception might be taken to the blind snail as an e.xample 
of a Flatlander, for possibly his body might occasionally 
lap the two sides of a flat stone as he curled over the 
edge of it. But one can imagine a blind snail-like being 
of such minuteness that the smallest particles of all other 
matter were much larger than its body. Such a crea- 
ture, though three-dimensional itself, might well have no 
suspicion of any dimension beyond infinite surface. It 
matters not in the least whether no such snail exists. 
The fact remains that such existence is imaginable, and 
that it is evident that in such a state of existence sceptic- 
ism as to the possibility of a third dimension of matter 
would be just as deep and instinctive as ours is against 
the possibility of a fourth. 

We may conclude, then, that our limiting of the num- 
ber of dimensions possible to space to three, is due to the 
circumstance that as we are constituted our senses cannot 
conceive a fourth. To say that, therefore, a fourth does 
not or cannot exist is to go further than we have warrant 
for. But though we cannot see or by any sense perceive 
a fourth dimension in addition to length, breadth, and 
thickness, we may be able reasonably to infer something 
about the character of such a hypothetical dimension, 
assuming, for the sake of discussion, that it may exist. 

Some of the properties of a fourth-dimensional " super- 
solid" have been dealt with by more than one writer, 
notably by Spottiswoode, in his Presidential Address to 
the British .\ssociation at Dublin in 1878, and by 
Howard Hinton, in his interesting little volume on the 
subject of the Fourth Dimension. 
I A suggestion is often met with that Time is the fourth 
! dimension of matter. Time may indeed be looked upon 
as a svmbol of the fourth dimension -an illustration of 
the possibility of a direction which is neither up nor 
down, nor from side to side, for in time are there not for- 



46 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



as a 
point, line, 
meaningless 



ward and backward directions which are neither of these' 
and which are extraspatial ? But, except in this figura- 
tive sense, the introduction of time as a solution of the 
fourth-dimensional question is merely a confusion of the 
problem. Time does not belong to the same category of 
thought with length, breadth, and thickness. Point, 
line, surface, solid - these follow each other 
development in orderly sequence, but 
surface, solid, time— these terminate in a 
1:011 sequitiir. 

Again, we may say that as a point is to a line so is a 
line to a surface, or we may say that as a line is to a 
surface so is a surface to a solid. This is intelligible, but 
to add, as a surface is to a solid, so is a solid to time, or 
to any portion of time, is unintelligible nonsense. More- 
over, the concept of time does not strike one as being (as 
the conception of a sphere would be) impossible to 
Abbott's Flatlanders, whereas it ought to seem even 
more so if it were actually two dimensions ahead of 
them. Indeed, it ought to seem impossible to oursehes, 
unless we are fourth dimensional beings. 

But without confusing the issue by incongruously 
introducing the concept of Time into the province of 
Space, let us see what may reasonably be conjectured as 
to tourth-dimensional existence. 

The elements of the inquiry are strikmgly illustrated 

by Hinton in some such way as the following : 

Two points joined = One line. 
Two lines joined = One square. 
Two squares joined = One cube. 
Two cubes joined = One (?). 
The series may iie set out in this way: — 



tion of more than three-dimensional form. The figure for 
the super-cube would, in fact, be like this:— 



> 


>j. ^-- 


X/ 


? 


C^ 


y 


N^ 


y 


^ 


y 








X 




^ 


"^ 


^^ 


,y^y^ 


\ 


^ ^ 


:^./ 





Fig. I. 

As the drawing of a cube to a Flatlander would seem 
to be only two squares on the same surface united by 
hnes also on that surface, so to us the above figure can at 
most only convey the idea of two cubes united by lines or 
perhaps by surfaces. We shall see this better if we draw 
the figure m perspective stereoscopically and examine the 
result m the stereoscope, when the two drawings will 
blend into one apparent solid. Here is such a stereoscopic 
diagram of the super-cube : — 



No, of Terminal 
Himensions Points. 



Joining 
Lines. 



Point 

Line 

S(|uare 

Cube 

Siij)er-rul)e 



n 




16 



Before we proceed to deal with the perspective repre- 
sentation of the last in this series of figures, the super-cube, 
it will be well to put ourselves back in imagination into 
.Abbott's Fldtland, and to consider what would be our 
b'latlander's impression of the perspective representation 
(jf the ( ube. '• Here is no third dimension," he would 
say ; ■' here are but two squares with lines joining them." 
lo us, who are accustomed mentally to connect such a 
figure with the similar retinal image which a solid cube 
forms in our eye, the concept of a third dimension is 
conveyed by association of ideas, but with the Flat- 
lander no such association of ideas would exist, because 
he would have had no experience of " thickness," 

him a Flatland 
ines. .Similarly, 
a full-face view of a cube would of course be to 
him simply a square, and in fact cannot be otherwise 
rendered on a flat surface. 

Now our relations to fourth-dimensional diagrams must 
be analogous. It is possible that we miglit make a 
pictorial rendering of a super-cube on paper, which to a 
being with senses capable of appreciating fourth-dimen- 
sional space would be suggestive of a fourth-dimensional 
super-solid, but to us, with no association of ideas to aid 
us, the figure must not be expected to afford a representa- 



experience 
and the figure would remain for 
one — two squares joined by four " 



Fig. 2. 

This slide, when seen in the stereoscope, shows us a 
peculiar looking figure, apparently three-dimensional. 
Now just is the perspective drawing of the cube suggests 
one tliree-dimensional figure to us but to the Flatlander a 
pair of united squares, so the above stereogram repre- 
sents a pair of united solids to us, but to beings with 
fourth-dimensional perception it might convey the notion 
of one super solid. 

It becomes e\'ident, therefore, that while our senses are 
(as at present) limited to three dimensions, we cannot ex- 
pect in the way thus far indicated to get any nearer to a 
concept of the super-cube. 

\'et there remains an experiment which carries us just 
a step further, and brings us to the \'ery verge of a solu- 
tion of our problem. 

Before we make this experiment it will -again elucidate 
the matter if once more we imagine ourselves for the 
moment in Flatland. There the drawing of a cube directly 
facing us would, as we have seen, be only one square, or 
more strictly one square exactly behind another. To the 
Flatlander, who does not know what " behind " means, it 
would be as though the two squares occupied the same 
space at the same time. 

Now the analogy from this is obvious, for in the same 
way under similar < ircumstances the super-cube of fourth- 



Mar., 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



47 



dimensional perception would to our perception seem like 
two cubes occupying the same space at the same time. 
They would really represent two separated rubes, but 
sejjarated in a direction neither up nor down, nor side- 
ways, nor cross-ways — in a direction of which we, with 
our three-dimensional conceptions, have no coj^nizance, just 
as the I'latlander had no cognizance of the meaning of a 
square being " behind " another square. The ()erspecti\e 
view of the cube when not seen full face would show tlie 
Flatlander the two squares only partially occupying the 
same space at the same time. In like manner we may 
put it that the super-cube, if presented to us broadside, 
would look like two cubes occupying the same space 
at the same time, while in other positions the two cubes 
would only partially occupy the same part of space. 

Now of this we can get some sort of representation by 
an interesting experiment with the stereoscope. Just as 
two flat drawings will give a representation of solidity 
when appropriately drawn and placed in that instrument, 
so two solids viewed through it will give some sort of idea 
of the super-solid. 

The experiment is striking and remarkable. Place in 
the centre of the field on each side in a stereoscope a 
solid cube. On looking through the instrument the two 
combine, and one cube is apparently seen. Now while 
looking at this one cube move slightly either of the culies 
as it lies in the stereoscope, and it w-ill be seen that our 
apparent one cube was composed of two occupying the 
same space at the same time. With the movement of 
one cube it is seen to pass partly out of the other, and we 
have an impression as to our super-solid exactly the 
counterpart of the Flatlander's impression of the cube as 
shown to him in the perspective drawing, first full face 
(the two squares occupying the same space and appearing 
as one) and then a more side view in which the two 
squares only partially occupy the same space. 

Using a cube on one side in the stereoscope and a ball 
of approximately the same size on the other the effect is 
still better seen, and without moving either the strange 
spectacle is revealed of a sphere and a cube occupying 
together the same part of space. 

The experiment affords, of course, but a suggestion of 
the fourth dimension, yet taken for what it is worth that 
suggestion is pregnant and of no small interest. 




Conducted by F. Shillington Scales, f.r.m.s. 



Microscopical Materia.1. 

By the kindnoss of Mr. \V. S. Rogers, of I'pper W'arling- 
ham, I was able la.st month to offer to the microscopical readers 
of " Knowledgk anij Scikntific Nkws" some "Comfrey" 
leaves (Symphytum ojjkuiale), which show well the beautiful 
basesof the leaf hairs. Mr. Rogers states that the appearance 
referred to is not seen in the leaves when fresh or when dried 
underpressure, but would seem to be brought into prominence 
by the blackening of the leaves when they lie fermenting on 
the ground in autumn. He adds that the material is intract- 
able to handle, the dried leaf being brittle and inclined to curl, 
and he has therefore punched them into '^ inch circles. They 
should, of course, be mounted as opaque objects. I regret 
that by a printer's oversight this notice was omitted last 
month, whilst the coupon was omitted the month before, thus 
causing unnecessary trouble to my many correspondents. 



Preserving Specimens of Orthoptera. 

A recent number ol tlir American J fin mil c/ .IpplicJ 
Mtcioscopy contains some interesting suggestions for preserving 
specimens of Orthoptera. .'\s the writer says, (heir compara- 
tively large size, juicy bodies, when alive or just killr-d, lirittle- 
ness of limbs and antenii.e wlien dried, llieir pronencss to 
fading after death, and their liability lo the attacks of mould 
and nuisciun pests, all seem to conspire against their preser- 
v.itiou. The larger and more showy specimens are best 
known, and the smaller and less brightly coloured forms are 
either entirely unknown or ha\e come to the notice of the 
\ cry few specialists who have ventured into an .almost forsaken 
field. There is, therefore, a rich field for investigation for 
any microscopist who is in want of a fitting direction for his 
studies. 

Placing these insects in alcohol and other li(|iiid preserva- 
tives has, in fact, overcome the objection to the soft juicy 
bodies that so (juickly shrivel and liecome discoloured wlien 
treated by the ordinary means of pre.serving insects ; but il 
has the disadvantage of ijuickly effacing the many bright 
colours conunon to such large niuubers of them, and even 
changes miiuite structural characteristics, ,so as to render the 
insects difficult of recognition. It al.so adds greatly to the 
space taken up l)y the collection, and renders their trans- 
portation difficult. Still it is an effective preservative 
against insect pests, such as Dcnncstcs, Sec. Orthoptera can, 
however, be handled "taxidermically " — ('.f., stulTed much as 
birds, &c., are stuffed. Instead of throwing the insects into 
spirits, they should, when captured, be killed in the cyanide 
bottle. The specimen being then hold in the fingers and 
thumb of the left hand, with a fine, sharp-pointed pair of 
scissors open the .abdomen by cutting across the middle of 
the two basal segments on the lower side, then reverse and 
cut the opening a trifle larger by nearly severing the third 
segment. Then extract all the insides (intestines, crop, 
ovaries, &c.). along with the juices, using fine forceps for this 
purpose, and wipe out the inside with a small wad of cotton. 
This being done, the insect may be pinned into a box or 
wr.ipped in paper and packed away for future use. 

The "stuffing "is carried out as follows. Cut some raw 
cotton into short pieces, and fill up the insect through the 
opening made as above, using similar fine forceps and taking 
care not to stretch or distend the ,al)domen beyond its original 
dimensions. When the filling is completed draw the edges 
of the severed segments carefully together, and press the sides 
of the abdomen into sh.ape with the fingers. This can all be 
done, after a little pr.actice, in four or five minutes' time. It 
will be found that the insect will not decay or turn dark, the 
original colours will be almost entirely preserved, and there 
is but little danger of attack by museum pests, on of the mould 
which so frequently spoils objects which .ire long in drying. 

Mouldy specimens can often be saved by being pl.iced in a 
tin box between wet cloths or blotting p.ipers well sprinkled 
with dilute carbolic ,icid, and left for twenty-four hours to 
thirty-six hours, or until sufficiently soft not to break when 
h.indled. Then pour some alcohol into a dish, and .add to it 
about one-twenfieth as much liquid carbolic acid. With a 
camel-hair brush carefully clean the entir(^ insect, taking care 
to wash every portion with the niixttue of alcohol and acid. 

In arranging in the cabinet the suggestion is made that 
nuich sp.ace can be economised by directing long antennas 
backwards along the sides of the insect, and by folding and 
crossing the legs beneath the body. In the Saltatoria. or 
jumping forms, the pin should be inserted near the back edge 
of the pronotum, a little to one side of the middle, .and direct- 
ing it to the rear, letting it pass downward through the meso- 
thorax, tliereliy tightly fastening together the two sections of 
the body. In the other forms, Bliillnidfd, Mmtlniiltn. and 
Plmsiiinuic-ii, the pin should be inserted l)ehind the pronotiuu 
through th(t middle of the body, taking care to select a solid 
portion for this purpose, without running the pin through the 
basal portion of any of the legs. 



The "Argus" Attachable Mechanical 

Stage. 

This stage was designed for use with the "Argus" micro- 
scope, noticed in the January issue of " Knowlkdgh," p.age 21, 
but it can be fitted to any ordinary microscope, being attached 



48 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Mar., 1904. 



by means of a thumb screw only. It is decidedly original in 
design. .\ friction wheel, actuated by a single milled head, is 
in contact with a broad brass plate attached to the clips which 
hold the slide. A steel spring gives the necessary pressure, 
and the spindle bearing the friction wheel and milled head is 
movable on a vertical pin. A glance at the illustration will 
make the principle clear, and it will be seen that the stage 



S^^^j 




BOjI 



,^■■1 

T* 




travels readily m a \ertical or horizontal direction, or in any 
intermediate diagonal direction, according to the position in 
which the milled head is held whilst rotating. Check pins in- 
dicate the horizontal and vertical positions respectively. By 
this means not only are rectangular movements obtained, but 
any desired diagonal movement is obtained in addition. The 
whole stage works with great smoothness and sensitiveness. 
The mechanism is entirely on one side of the stage, so that 
none of the working parts are in the way of the instrument. 



Quekett Microscopical Club. 

The 409th ordinary meeting of the Club was held on Decem- 
ber is. at 20, Hanover Square, W., the Vice-President, A, D, 
Michael, Esq., F.L,S., in the chair, A most interesting col- 
lection of diffraction gratings of various kinds was on view, 
and the exhibitor, Mr, Julius Rheinberg, F,R.M.S,, briefly 
described them and pointed out the curious optical effects 
obtainable. Among the most interesting of the exhibits was 
a reflecting diffraction grating on plate glass, silvered on the 
grating side, ruled by Colonel L. Paxton, of Chichester, It 
consisted of intersecting systems of circles. Each system 
consisted of a series of excentric circles, the locus of their 
centres being an intermediate circle. When exposed hori- 
zontally below a flame, an observer stationed a few yards 
away could see four intersecting rings of light stereoscopically 
projected several inches in front of the mirror, whilst a 
similar system of rings was seen several inches behind the 
mirror, 

Mr, Rheinberg then read a paper ''On an Overlooked Point 
concerning the Resolving Power of the Microscope." It dealt 
with a discovery made from the theoretical standpoint some 
years ago by Dr. Johnstone Stoney, F,R.S,, which had only 
recentlv been practically demonstrated — viz., that an objective 
would resolve and separate two dots or Imes of a known 
distance apart, although unable, owing to its N,.\,, to resolve 
a series or band of dots or Hues at equal similar intervals. 
The experiment was practically demonstrated to the Club, a 
Grayson test plate of 15,000 lines to the inch being used for 
the purpose, with a Zeiss S mm, apochromat. and a 27 mm. 
compensating ocular. 

Mr. D. J. Scourfield, F.R.M,S,, then gave an epitome of the 
third part of his Synopsis of the British Fresh Water Entomo- 
straca. It dealt with the ( Jstracoda, of which we have about 
62 species, nearly all widely distributed ; the Phyllopoda, of 
which there is only a single form now recorded, another form, 
.•l/j».s£((Hi-n/o>-;«/s,being apparently extinct: and the Branchiura, 
with two species, one lieing extremely rare. This was the con- 
cluding portion of Mr, Scourfield's valuable series of papers 
on the British Entomostraca, 

The 410th ordinary meeting of the Club was held on 
January- 15, the President, Mr,-(ieorge Massie, F,L,S,, in the 
chair. There was a large attendance, Mr, C, Rousse- 
let, F.K.M.S., read a paper ou '■.\ New Freshwater Poh'zoon 
from Rhodesia," which was illustrated both by a diagram and 
by specimens shown under the microscope. The polyzoon 
referred to differs in many ways from all other known species, 
and is especially characterised by the production of elliptical 



statoblasts having five spines at each end, the spines being 
armed with minute hooks, 

Mr. J. T. Holder exhibited an interesting series of lantern 
slides of Foraminifera from photographs taken by himself. 
The specimens varied much in size, some of the large groups 
being J inch in diameter, and containing several hundred 
selected specimens from -jifj to i inch in diameter. .\ 4-inch 
objective was used, and in spite of the difference in focal plane 
the photograph was quite successful. Other photographs were 
taken with 2-inch and i-inch objectives. The exposures varied 
from a few seconds to three quarters of an hour, an isochro- 
matic screen being invariably used. The camera and ap- 
paratus emploved were also shown on the screen. 

Mr. Earland ga% e a brief description of the slides, and con- 
gratulated Mr, Holder on his success, and especially on the 
way in which the glassy transparency, which was one of the 
most beautiful features of the hyaline Foraminifera, had been 
reproduced in the photographs. .'Attention was particularly 
drawn to Frondicutaria aluta from Cuba, found at the depth of 
700 fathoms. The genus was now almost extinct, but was 
abundant in Secondary times. .\t present it was found in 
numbers in only two small areas in the world, each widely 
distant from the other, namely, the Caribbean Sea and the 
shores of New Guinea. .Attention w-as also called to the great 
difference in the form and structure of the specimens shown 
on the screen. This was due to the different methods of 
growth, which, in turn, w-as a result of the difference in size of 
the primordial chambers. It was a typical instance of dimor- 
phism, and the two specimens represented the megalospheric 
and microspheric types respectively. Two especially interest- 
ing slides were Polystomella craticiilata and Orhulina uiiii-ersa. 
In the first the foraminifer was show-n side by side with 
a cast of the animal's body, the cast being quite perfect, 
and exhibiting every detail of structure, the canal system 
and primordial chamber being sharply marked on the 
screen. In the slide of Orhulina iinivirsa some of the 
spherical details had been laid open in order to show 
the internal Globigerina shell. This was shown in various 
stages, from the perfect shell, attached by five spines to the 
inner surface of the sphere, and not distinguishable from a 
pelagic Globigerina, to the last disappearing chamberlet. The 
mystery of these internal chambers, which were only found in 
a small percentage of specimens, was unsolved ; but a theory 
had been invented to account for them. It was supposed 
that the pelagic Globigerina, in order to protect its delicate 
spinous shell from the action of the waves, formed a spherical 
shell outside it, and the internal shell being then of no further 
use was gradually absorbed ind disappeared. A number of 
photographs of rock-sections next exhibited showed Foramini- 
fera ill situ, and exemplified the important part played bv 
them in the structure of the earth, more important than all 
other animals put together. They were amongst the very 
earliest inhabitants of the earth, their remains being found as 
far back as the Lower Cambrian strata, and some of the 
genera, perhaps even species, found there were still in exis- 
tence. They formed enormous masses of limestone in carboni- 
ferous times, and the gault and chalk were largely composed 
of their remains. But they reached their greatest develop- 
ment in Tertiary times, when the famous Nummulitic and 
.\lveolina limestones were built up by them, the deposits 
stretching in an almost unbroken series across Europe and 
the western half of Asia, reaching a thickness in places of 
many thousand feet. Their modern representatives were both 
small and infrequent. 

In addition, a number of marine organisms, admirably pre- 
served, were shown under microscopes on behalf of Mr, H, J, 
Waddington, a former member of the Club, 



Royal Microscopic.\l Society, December 16, Dr. Henry 
Woodward. F,R,S,, President, in the chair. Mr. F, W, Watson 
Baker exhibited under microscopes an exceedingly complete 
and valuable series of slides, 16 in number, illustrating the 
development of an ascidian from the fertilization of the ovum 
to the larval stage. The slides were prepared by a gentle- 
man well known to many of the Fellows, who had been 
most successful in his management of marine aquaria. Dr. 
G. J. Hinde read a paper " On the Structure and .^.ffinities of 
the Genus Pomsphara." which was illustrated by diagrams, 
mounted slides under microscopes, and specimens, many col- 
lected by Dr, Hinde in his garden at Croydon, which had 



M/ 



1904.] 



KNOWLEDGE .t SCIENTIFIC NEWS. 



49 



been weathered out of the chalk. — January 20, Annual Meeting 
the President, Dr. Henry Woodward, F.K.S., in the chair. 
The Curator, Mr. C. Kousselet, e.xhibited an old microscope 
by Plossl, of Vienna, which had been sent on approval. It 
has a folding tripod foot which carries a short column sur- 
mounted by a compass joint for inclining the instrument. To 
a hinged attachment of the compass jomt a triangular steel 
bar is fixed. On this bar slides a bracket, having a curved 
arm, to which the body of the microscope is secured. A 
rack is sunk into the base or b.ack of the triangular bar for 
the coarse adjustment, the pinion of which is contained in the 
sliding bracket. The stage, which is also carried by the 
triangular bar, has slow rectangular movements of very 
hniited extent. There is also a micrometer movement, right 
and left, for measuring objects, and a fine adjustment lor 
focussing. There are six object glasses which can be used 
separately or in various combinations of two or three glasses. 
Among the apparatus is a lenticular prism for illuminating 
opaque objects and two diaphragms for reducing the diameter 
ot the reflecting surface of tne mirror. The ballot for officers 
and Council for the ensuing year was then taken, and Dr. 
Dukinfield H. Scott, F.K.S., was elected President. The other 
business of the annual meeting having been disposed of. Dr. 
Henry Woodward, the retiring President, proceeded to give 
his annual address, taking as his subject " The Involution of 
Vertebrate Animals in Time." His paper was illustrated by 
diagrams, drawings, and slides, about So in number, shown 
upon the screen. 

A Novel Electric Traction System. 



In No. 2 of the EUktrotechnischer Anzcigcr E. Leuggenhager 
describes an electric railway traction system which is being 
developed at the present luoinent by a Swiss " Studiengesells- 
chaft," appointed for the purpose of finding out an electric 
railway system suitable for that country, which, on account of 
her dependency on the foreign coal market, evidently should 
endeavour to utilize her wealth in hydraulic power. Speeds, 
on the otuer hand, are limited there on account of the steep 
gradients, small curves, and numerous stoppages. The system 
in question uses steam locomotives hentai by electricity. Elec- 
tric heating, as is well known, will work with the highest 
possible ethciency, so that the total efficiency will mainly 
depend on the output of the mechanical part of the locomo- 
tive, being the steam-engine proper. Any coal steam loco- 
motive could readily be converted into an " electrothermical' ' 
locomotive by simply replacing the fire-box and boiling-tube 
of the boiler by a number of parallel electric heating-walls 
rumiing througnout the boiler and being co[nposed of two 
copper or iron sheets. The author suggests using in this con- 
nection the well-known Prometheus heating elements. The con- 
sumption of current would depend on the consumption of steam. 
Let the boiler be designed lor accommodating 4000 litres of 
water, which are to be brought within 3 hours from 10' up to 
about igo^ C, corresponding with a steam pressure of 50 kg. 
per sq. cm. In the case of an efficiency only as high as 90 per 
cent, the following data would be obtained : 4000 1. of water 
would require, in order to be brought to the above tempera- 
ture, 4000 X iSo = 720.000 kg. cal. ; i kg. cal. = 1275 eft. 
watt, hours, therefore 720-000 kg. cal. = about goo eii. kw. 
hours, or, distributing this amount over 3 hours = about 
300 kw. A consumption of steam of 1000 kg. per hour would 
accordingly require a supply of current of about 225 kw. As 
regards the advantages inherent in theelectrothermic system, 
the resistance of the steam accumulator against current shocks 
should be mentioned. There is the further advantage of both 
direct and alternating currents being practicable in this con- 
nection, any desired combination being suitable. The mean 
efficiency of electrothermic locomotives, being about the same 
as that of an electromotive machine ot the same size, would 
be about 5o to 70 per cent., whereas the total efficiency of a 
railway system, on account of the more advantageous utiliza- 
tion of tne load, would be higher for the former. Further- 
more, the adoption of electrothermic service may take place 
gradually, being much easier than that of electromotive 
service, on account of the lower cost of the conversion and 
the easiness with which the personnel may be trained for the 
new service. A possible conversion of electrothermic into 



electromotive railway service would finally be readily made 
should the electromotive service in future be so improved as 
to become superior to the electrothermic system. — A.G. 

Geodetical Irvstrvirrvents. 



I'roiii Mr. James Hicks, of llatton Ganlen, we have rcceivcil a 
calaloguc ol the new types oi liaiul surveying instriuncnts designed 
and patented by Sir Howard (hubb. I-".K,S. 'iliese extremely 
ingenious and tisclul instruments were designed by the inventor 
primarily (or the use ol those wliose work in surveying required 
simple, portable, and easily compreliensible instruments lor rapid 
work, file principal advanl.ages common to all the instruments 
.ire tlie film surface of the glass, which is of a kind capable both of 
rellecting and transmittin.n a considerable portion of the light which 
lulls on It ; and the adoption of the collimator system for parallel- 
isiny ra\s. Hy the use ol the Keynolds-tjrubb film, light Irom two 
diflerent directions can be directed into tile eye of the oliscrver 
without recourse to the inconvenient old method which was known 
;is "dividing the pupil." The collimator system of parallelising 
rays has also great atlvantages in convenience and simplicity of 
observation. Among the instruments to which these methods 
have been specially and advantageously applied are the small clino- 
meter and prismatic compass and a level. Mr. llicks also com- 
prises in liis catalogue of these new types ol hand surveying in- 
struments, an optical square fitted lor use with the naked eye, an 
attachment for a telescope, a graphonieter, and a pocket surveying 
instrument. 

REVIEWS OF BOOKS. 



Who's Who, ys. Od. (A.&C. Black), grows stouter every year, 
and now contains no fewer than 17,000 biographies. Its great 
usefulness is so well recognised that it need not be dilated 
upon. Some few of the biographies might, one would think, 
be curtailed, especially as regards " recreations," one of which, 
we note, reads " homely table games of cards, chess, Ijack- 
gammon, halma, cribb,age, &.c." Otherwise, the succinct ac- 
counts of the lives of every Englishman of any note are most 
complete, and just what one requires. 

Who's Who Year Book, is., is a small book containing the 
tables which were formerly incorporated in Who's Who, but 
which have been deleted from time to time to make room for 
the evcr-increasin.g number of biographies. These tables are 
most useful for reference, including as they do not only .such 
as are to be found in many other annuals, but also lists of 
Koyal Academicians, Bishops, Newspapers and Magazines, 
l^seudonyms and Pennames, Principal Schools (with number 
of pupils and cost), I'ellows of the Koyal Society, Societies, 
&.O., Chairs and Professorships, Heirs of Peers, iS;c. 

The Englishwoman's Year Book, 2s. 6d. (.'\. &. C. Black), " aims 
at giving some idea of the extent of women's work and 
interests, and some guidance to those who want to help their 
fellow-creatures, whether as individuals they live lives of 
which their own home is the centre, or take a wider view of 
their opportunities and responsibilities,'' and has a wonderful 
mass of useful information packed into its 350 pages. 

BOOKS RECEIVED. 



[I'he notice oj books in this column does not preclude the revieio of 
them at a later date). 

Studies in Hcterogenesis, by H. Charlton Bastian, M.A., 
.M.D.Lond., F.K.S. (Williams and Norgate, one vol.; price 
31s. 6d.) .\ monumental work, illustrated with more than 
eight hundred micro-photographs, and summing up the whole 
number of instances of the apparent transformation of the 
substances of parent matrices into new forms of lite. The 
author examines the alternativ'C explanations of these pheno- 
mena — (i) That the resulting forms of life are due to the 
invasion and multiplication of parasites within what appear 
to be parent organisms ; (2) that the resulting forms of life 
are in reality heterogenetic products originating from the 
very substance of the organisms from which they proceed — - 
and gives his reasons for adopting, after prolonged and care- 
ful study, the second of these theorems. 



50 



KNOWLEDGE & SCIENTIFIC NEWS. 



[M 



AR., 1904. 



The Worship of the Dead, by Colonel J. Gamier. (Chapman 
and Hall, one vol.). Colonel J. Garnier.s work on "The 
Worship of the Dead" (Chapman and Halli deals with the 
origin and nature of Pagan idolatry and its bearing upon the 
early history of Egypt and Babylonia. The voluminous 
materials collected by previous writers on the subject are 
here set forth within a moderate compass and in a readable 
form. The book is profusely illustrated with interesting 
examples of the statues of ancient gods. 

Cassell's Popular Science (Cassell and Co.). edited by Ale.x- 
ander S. Gait, with contributions from T. C. Hepwort'h, Pro- 
fessor Bonnev. Frank Weedon, John Fraser. F.L.S., Wilfred 
Mark Webb. F.L.S., Dr. .\ndrew Wilson. Dr. Bernard Hol- 
lander, and William Ackroyd, F.I.C. The subjects range from 
radium to carnivorous plants, and from the transit of Venus 
of 1SS2 to the working dynamo. The articles, of which there 
are some sixty, are clearU- and well written, and in every 
respect justify the title under which they are collected. 

British Tyroglyphida, by Albert D. Michael. F.L.S., F.S.S., 
&c. Vol. II. (Printed for the Royal Society.) This volume 
contains the description, with plates, of the genera and species 
of the British Tyroglyphids. from the genus Chortoglyphus 
to the Tyroglyphus Wasmanni. .\ list of foreign species is 
added. 

The Old Testament and Historical Records, bv Theophilus 
Pinches. LL.D. lOne vol. Second Edition. S.P.C.K.l In 
the second edition of the " Old Testament in the Light of the 



Historical Records and Legends of Assyria and Babylonia,'' 
Dr. Pinches adds some exceedingly valuable and interesting 
matter on the Laws of Hammurak. together with a translation 
of the laws and notes on Delitzch's lectures on this subject. 

A School Geometry. Parts I.-V. By H. S. Hall, M.A.. and 
F. H. Stevens. M..\. (Macmillan. One vol. ; price 4s. 6d.) — 
This is a publication, in one volume, of a geometry for schools 
based on the recommendation of the Mathematical Associa- 
tion and on the new Cambridge syllabus. 

Descriptive Chemistrj-, by Lyman C. Newell. Ph.D. One 
vol.. with supplementary vol. of experiments. (London: 
D. C. Heath; price 4s. 6d. and is. 6d.i — Intended for teachers 
who wish to emphasise the facts, law-s. theories, and applica- 
tions of chemistry. The experiments have been prepared for 
limited laboratory facilities. 

■^^ rf^> -^i ^^ ^*i 

CKess Problems. 

Owing to the great amount of matter which we have on hand 
we have felt it necessary to again postpone pubhshing the 
Chess Problems. We should be very glad to have the opinions 
of those interested in this subject as to the continuance or 
otherwise of the Chess Column. 



LAST YEAR'S WEATHER— MARCH, 1903. 



DISTRIBUTION OF MEAN TEMPERATURE. 



f 




RAINFALL. 



♦•96 



73 



1^2 It 

/ ■■■5S«( 

"'^^ AoeV. 3 86 V* 




2 02 



C^I30i 6-24.. «^ '♦e2» . 180 ... 



,1 65 



* S6»^_/-^ 



9L, 



The general distribution all o>fr <iur islands agreed \ ery fairly 
with the normal, but the actual \alues\\ere above the average 
in all localities excepting the west and north of Ireland. 



3-74. *"^.^ 3,90 

» 

339 






33 






Rainfall »a.- considerably in excels of the average over the 
countr>' generally, but was rather deficient on the east coasts 
of England and the north-east coasts of Scotland. Over the 
western half of the Kingdom the excess was very large, the 
amount at manv stations being more than double the average. 



KDomledge & Selentifie flems 

A MONTI II A' JOURNAL OF SCIENCE. 



Vol. I. No. 



[new skrifs ] 



APRIL, 1904. 



E Entered at 1 
Stationers' Hall.J 



SIXPENCE. 



> Contents and Notices. — See Page VII. 

The Protective 
Resemblance of Insects. 

By Percy Collins. 

The story of insect life has many phases of entrancing,' 
interest ; nor is this altogether surprising when we 
remember that the earth, the air, and the water are alike 
peopled by the vast army of the six-footed. These varied 
conditions of life have left their mark not only upon the 
habits and movements of insects, but upon their colour, 
their form, and their instinctive attitudes of repose. So 
that although insects are more diverse than any other 
natural group of living creatures, the explanation is 
simple; they are and have been subjected to almost every 
condition under which life is known to be possible. 
Thus, to the entomologist, every difference of form, 
colour, or attitude seems worthy of serious investigation. 
He realises that an unusual tint or a quaint pattern carries 
with it a definite meaning — that it is in some way linked 
to the ancestral history of its possessor. Often enough 
this meaning is mysterious. But occasionally the colours 
and form of an insect, or of a group of insects, can be 
explained as the direct outcome of certain known in- 
fluences. Not infrequently such interpretations reveal 
the fact that the shape or colour of an insect, or both in 
combination, are mainly responsible for its well being. 
The creature's peculiar appearance either mystifies its 
enemies or enables it to approach unobserved the smaller 
insects upon which it preys. The whole subject, to 
which the general term " mimicry " is commonly applied, 
constitutes one of the most fascinating phases of entomo- 
logical study. 




The simple protective resemblance of an insect may 
be either general or special. That is to say, the protec- 
tion may originate in the mere likeness of an insect's sur- 
face colouring to that of its customary surroundings, or 
it may consist in an actual reproduction in both form and 
colour of a certain object with which the creature is 
commonly associated tliroughout its life. 

Instances of general protective resemblance must be 
familiar to observers in all countries. The numerous 
moths which are accustomed to rest for hours together 
upon rocks or tree trunks are oft-cited examples. Con- 
spicuous among tliem is the whole genus Calocala, the 
various species of which are widely distributed in the 
Pakvarctic region and elsewhere. These moths have 
brightly coloured hind wings, the usual tint — which has 
given to them their popular title of " Red-underwings " 
— being some shade of crimson or pink. When they are 
on the wing they are sufficiently conspicuous, and are 
liable to be snapped up by a hungry bird. But when at 
rest upon a tree trunk in tlieir customary attitude of 
repose, the soft grey or brown colour of their fore wings 
produces a general effect so well in keeping with the 




Catocala sp, Japan. 



Catocala sp. Japan. At rnst on bark. 

rough surface of the bark, that they are' extremely diffi- 
cult to detect. Their colour pattern alone constitutes a 
most effectual hiding. 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 



The same may be said of countless other moths, especi- 
ally of the great Noctiia group ; and it is interesting to 
trace how closely the colour of the fore wings in a given 
species corresponds to its habitual resting place. The 
appearance of all kinds of bark, of moss}' twigs and of 
lichen-covered rocks is faithfully reproduced ; nor is it 
necessary to search beyond the moths of our own islands 
for striking examples. 

Many butterflies, especially of the great group .Vvw;/'/ia- 
liiuv, possess — in the tints of their under side— a general 
resemblance to the ground upon which they habitually 




Hamanumida dedalus. Africa. 

settle. Moreover, many species seem to have acquired 
the trick of inclining their folded wings out of the 
perpendicular, by this means covering, or minimising, 
their own shadow, as well as bringing the protectively 
coloured underside into more prominent view. This 
habit may be observed in many of our common " brown " 
butterflies — for instance, in Pyrarga mcgaera and in Satyvus 
semde. In connection with this apparently acquired aid 
to protected resemblance, the habits of Hamanumida 
dcdalus, an African butterfly, are exceedingly interesting. 
It is authoritatively stated that this insect rests in West 
Africa with its wings folded over its back after the 




soil, is exposed to view. In South Africa, on the other 
hand, the same insect sits with its wingsexpanded, show- 
ing the brownish grey upper side which harmonises with 
the colours of the rocks in that region. 

Many of the Coleoptcra, from their colour, are almost 
indistinguishable when resting upon lichen-incrusted bark. 
The accompanying photograph of a Longuorn from 
Bhutan admirably illustrates this phase of general protec- 
tive resemblance. Although the insects are in full view, 
the casual glance quite fails to detect their presence. 
This surprising result is largely gained by the manner in 
which the colour is, as it were, cut up into dark and light 
patches. This is particularly noticeable in the long 
antenna", the sharp outline of which is entirely effaced 
from their being coloured in alternate lengths of black 
and grey. 

Turning from general to special protective resemblance, 
we find a number of extremely interesting and remark- 
able examples, especially among exotic insects. The 
butterflies of the genus Kallima — " leaf butterflies," as 
they are popularly called — bear striking testimony to the 




Hamanumida dedalus. (Underside.) .Mrica. 

common habit of butterflies, in which position its tawny 
under surface, which agrees with the general tone of the 



Apallmna ducalis. Male and Female. Bhutan. On Lichenous Bark. 

powers of natural selection. When flying in the full 
sunlight, their wings flash with colour, but directly they 
come to rest upon a twig they are, to all appearances, 
brown and withered leaves. This sudden transformation 
is made possible by the tinting of the under surface of 
the wings, and by the curiously erect attitude which the 
insect is able to assume — its wings drawn upright over 
the back and its head and antennae concealed between 
their anterior margins. When we consider the mar- 
vellous accuracy of the colour imitation, the uncommon 
shape of the insect's wings and its unusual pose, the leaf 
butterfly must still be ranked as one of the most amazing 
instances of protective resemblance yet recorded, not- 
withstanding the many marvels which have been brought 
to our notice within recent years. 

The larvae of moths grouped under the title Geome- 
tridcT usually bear a curiously accurate resemblance to 
liitle twigs or sticks, both in shape and in their brown 



April 1904] 



KNOWLEDGE & SCIENTIFIC NEWS. 



53 




Kallima niachfs. India. Two Specinjens at rest among leaves. 

or grey colouring. Moreover, this deception is materially 
heightened by the unique attitude of repose obtaining 
among these caterpillars, which differ from most lepidop- 
terous larva; in possessing only two instead of five pairs 
of pro-legs. These are placed at the extreme posterior 




riul 111 the body, while the three pairs of true legs at the 
other extremity arc usually exceedingly diniinuti\e. 'l"he 
perfect stick-likeness is gained in the following manner. 
The caterpillars of the GconulridfC usually feed at night. 
When daylight comes, or under Ihe stimulus of alarm, 
they take a tirm hold upon ilic iwig with their four pro- 
legs and stretch out their cylindrit al body stiff and 
straight at an acute angle. In this position they are 
capable of remaining, absolutely motionless, for liours 
together. But to counteract the terrible strain which the 
attitude would impose u])()ii the body of the caterpillar, 
each usually spins a strong, though practically invisible 
silken thread from its mouth to the twig fin which it rests. 
A family of insects remarkable above all otliers for the 
almost universal protective resemblance of its members 
is the Phasmida. In order to understand these creatures, 
which are numerous in all tropical countries, it is neces- 
sary to know something of their habits, llnlike their 




Three Caterpillars ol Hemerophila abruptaria. l-.iifilaml 



ClitumnuA Sundaicus. Stick-hke I'h.isiiiiil, 

near relatives, the Mantidce or " praying insects," which 
are voracious insect eaters, the Phasmida' are exclusive 
vegetarians, feeding greedily upon the leaves of the plants 
which form their resting places. In movement, Phasmids 
are extremely sluggish, and many of the species — being 
apterous or possessing, at most, only rudimentary wings — 
are incapable of flight. Thus, they are much exposed to 
the attacks of birds and other insectivorous creatures — 
have been so, in all probability, forages past. This per- 
secution might be supposed to foster any variation in 
shape or colour likely to be of protective value. And, as 
a matter of fact, the whole of the Phasmidce, almost with- 
out exception, have undergone striking modifications in 
the direction of special resemblance. 

As a rule, the bodies of these insects have become 
greatly lengthened, while the legs are long and slender. 
Those known popularly as " walking sticks," of which 
the Cliluinnus sundaicus shown in the accompanying photo- 



54 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 



graph is a good example, are generally of a uniform 
brown tint. Many of the species have curious knotty 
protuberances, or even prickles, upon their bodies and 
legs, this, of course, adding much to the stick-like aspect 




winged Phasmld, showing two portions into which each win^^ is divided. 

of the insect. After examining a dried specimen of a 
"stick" Phasmid, one does not need the assurance of 
foreign collectors to believe that these creatures are prac- 
tically invisible when at home among the branches of 
their native shrubs. 




Winded Phasmid. at rest among grass blades. 



Other Phasmidce — fairy-like creatures with exquisitely 
coloured wings — resemble grass rather than twigs when 
at rest. Their bodies, legs, antennae, indeed every part 
of them, with the exception of certain portions of the 
wing area, is green. Their first pair of wings is rudi- 
mentary ; but their hind wings are ample, gauzy, and 
fan-like in their manner of folding. A narrow strip at 
the anterior margin of each wing is thickened and green 
in colour, contrasting strangely with the gauzy area, 
which is usually bright pink. Under this narrow cover, 
the whole of the bright, flimsy portion of the wing is 
packed away when the insect comes to rest. And so 
closely are the wings folded that the casual observer 
imagines the creature to be apterous. It is, indeed, the 
exact counterpart, of a crumpled or slightly-thickened 
grass blade, while its legs and antenna;- are too slender to 
attract much notice. 




Phyllium sp. Female. Ceylon. 

Perhaps the most remarkable genus of the Phinmid<r 
is PhyUiuni, whose members — unlike the majority of their 
allies, which we have seen to be slender and lengthened 
— have the body and legs flattened into leaf- like plates. 
In some instances this design of leaf resemblance is 
carried out with amazing accuracy and attention to 
detail. Every portion of the insect seems modified to the 
one end. Its body is flat and leaf-like ; its wings and 
wing cases (where present) look like leaves; while even 
its legs are flattened and fitted with leaf-like appendages. 
To crown all, the colour of these insects, when alive, is the 
brightest and freshest of vegetable greens; so that, when 
crawling among herbaceous foliage, a species of PhyUiiim 
is, to all appearances, not an insect at all, but just a 
moving mass of leaves. 

Certain species of the Mcmhracidtc, which are ratlier 
small, frog- hopper-like insects, have a most curious 
thorn-like or knot-like appearance. This is gained by an 
unusual de\elopment of the pronotum, which is produced 
behind into a long process, or, it may be, into a kind of 
shield. In the case of Ltnbonia spinosa, from Brazil, this 



April, 1904.] 



KNOWLEDGE .^ SCIENTIFIC NEWS. 



3D 



process extends completely over the insect, and is drawn 
upwards to a point. In fact, it is an exact imitation of a 
sharp vegetable thorn, from which it is indistinguishable. 
Thus, the Umboiiiii lias merely to crouch down upon a 
thorny twig and withdraw its legs beneath the shieUl- 
like pronotum to be completely hidden. 

The above examples include some of the more striking 
instances of protective resemblance, both general and 
special. They must not, however, be regarded as even 
typically exhaustive, for sticks, leaves, .mosses, and 
lichens, though common patterns, are by no means the 
only objects copied in insect colour and form, blowers, 
seed pods or seeds, patches of mould or decay — even the 
droppings of animals and birds are all prototypes for 
insect disguise. Moreover, the modilications of form and 
the varieties of colour and marking which ha\e been 
called into being by the need for protection are too 




Umbonia spinosa. Bra/il. (.Middle "thorn" on upper part of Stoiii). 

numerous even to tabulate. In the course of his investi- 
gations, every observant student will constantly have new 
and striking instances brought to his notice, even though he 
may never wander beyond the confines of his own county. 
But it should be recollected that to form a true esti- 
mate of the protective value of an insect's colour and 
form, it is absolutely essential to study them in relation to 
their habitual surroundings; for, as a rule, it is<iuite im- 
possible to tell from a casual examination whether a 
special appearance is protective or not. A butterfly in a 
cabinet drawer is merely a scientific specimen. Its colours 
may be bright and beautiful, dull and unattractive, as the 
case may be ; but suspended above a surface of white 
paper, they have no special significance. On the other 
hand, when the insect is alive and among its natural sur- 
roundings, its colour and shape are often seen to have a 
direct bearing upon its well-being. Thus the study of 
living specimens cannot be too strongly urged upon the 
student — not of entomology alone, but of every branch of 
natural history. 

^^^^^^ 

A RATHER unexpected geographical discovery has been made by M 
Gabriel Marcel, who in a Paris shop found an Eighteenth Century 
map on which is shown the project put forward by M. de la Bastide 
for a canal across the .\merican isthmus by the Nicaragua route. 
The map. which is finely e.xecuted, is printed on silk, and from its 
shape was clearly intended for the decoration of a fan. It shows 
three ships in sail on the Lake of Nicaragua, and marks the 
suggested route to the west of the lake Though M de la Hastide's 
project is a matter of geographical history — he wrote a memoir on 
it in 1791 — the map's existence had been hitherto unsuspected. His 
was a plausible project, but he did not by any means realise its 
difficulties, for he was a theorist who never visited the spot, and 
who depended on the very inaccurate maps of other people 



Professor 
Adam Sedgwick. 

The Man and his Work. 

When, just over 30 years ago, at a meeting lieUl in the 
Senate House, Cambridge, the idea was first mooted of 
a memorial to Professor Adam Sedgwick, if was said of 
him in the words of Shakespeare, " His life was gentle; 
and the elements so mixed in liim that Nature might 
stand up and say to all the world. This was a man." 

It is well at this moment, wlien the Sedgwick Musemn 
is an actual connnemoration, to recall the up-bringing 
and achievements of the subject of this splendid allusion. 

The son of a Yorkshire clergyman, Sedgwick', at tiie 
close of his early education, proceeded to Trmity College, 
Cambridge, duly took a degree, and was classed as 5th 
Wrangler. In 1810 he was made a Fellow of his College, 
and engaged in teaching; and in 1 81 6 was ordained. Hut 
it was not as a divine that his repute became established, 
but as a leader in British geology, a soldier in the early 
campaigns of the science. Klected Woodwardian Pro- 
fessor of Geology in iSiS, although knowing, we are told, 
. omparatively little of the study he was to teach, it 
seemed as if he was predestined for its successlul pro- 
secution, and it was not long before he stepped into 
the front rank as an original iiuestigator. His lectures, 
which formed a novel feature when he entered up(}n 
the duties connected with tiie Woodwardian Chair, at- 
tracted general attention, while at the same time the 
Professor lost no opportunity of promoting and en- 
couraging the extension of natural science teaching in 
the curriculum of university studies. Those were early 
days in geology — in fact, the long-clothes stage and the 
authorities looked askant at the iconoclastic science, 
mindful, too, of what it might bring in its train. Un- 
doubtedly, in the case of many other men, efforts to 
obtain the recognition of geological and allied studies 
would ha\e been foredoomed to failure in the face of 
the frowning repressiveness which prevailed at Cam- 
bridge. But Sedgwick was endowed with special quali- 
ties for the task in hand, and never deviated from the 
chosen path. Moreover, his charming personality and 
adornments of character disarmed permanent opposi- 
tion. Of these characteristics there is ample testimony 
in the opinions (jf his contemporaries. Three prominent 
hopes possessed his heart in the earliest years of the 
Professorship, in his own words expressed thus : — 
" First, that 1 might be enabled to l)riiig together a 
collection worthy of the University, and ilfustrative of 
all the departments of the science it was my duty to 
teach ; secondly, that a Geological Museum might be 
built by the University, amply capable of containing its 
future collections ; and, lastly, that I might bring to- 
gether a class of students who would listen to my teach- 
ing, support me by their sympatliy, and help me by 
the labour of their hands." The fulfilment of these 
hopes is, of course, a matter of history. 

Sedgwick was the author of a lengthy series of papers 
in British geology, but he wrote no separate woriv. In 
particular is he known for his elucidation of the Pala;o- 
zoic system, in which he collaborated with Murchison. 
He investigated the Magnesian Limestone of the North 
of iMigland, and the geology of Wales engaged his 
earnest and successful study. He was elected a Fellow 
of the Royal Society in 1821, and in 1863 was awarded 
the envied Copley medal -a year previous to the award 



56 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 



made to Darwin — for his observations and disco\eries 
in tile Palaeozoic series of roclvs, and more especially for 
his determination of the characters of the Devonian 
system. Other honours were showered upon him, both 
at home and from abroad, including, in the former 
category, the Presidency of the Geological Society and 
of the British Association. 

As a contemporary of L)ar\vin, Professor Sedgwick 
was confronted with that naturalist's theory respecting 
the evolutionary order of Nature. His attitude was uni- 
formly hostile to the hypothesis, and he would have 
none of it. In this connection it is interesting to note 
that, at the time of the publication of the " Origin of 
Species," Darwin was exceedingly sore at the " rabid 
indignation " displayed by Sedgwick, nevertheless he took 
occasion to refer in affectionate strain to the veteran 
geologist's noble heart and instincts. 

Sedgwick never married. He continued his occupancy 
of the professorial chair until his death, in i>^73, which 
took place at the ripe age of eighty-eight, and he was 
buried in the ante-chapel of Trinity College. 

Finally, let these words of his further proclaim the 
man : " My labour is its own reward. It gave me health, 
and led me into scenes of grandeur which taught me to 
feel in my heart that I was among the works of the great 
Creator." 

Telegraphically Trans- 
mitted PhotogrsLphs. 

By Dr. Alfred Grauenw it/. 



Many attempts ha\e been made to transmit handwriting, 
photographs, drawings, (S;c.. by telegraphic means, and the 
more or less successful solutions which have been suggested 
for this problem of late years are numerous. Selenium cells, as 
shown by Herr Ruhmer's successful experiments in the field 
of wireless telephony, give a ready means of detecting and 
transmitting by telephone even very slight fluctuations in the 
intensity of a source of illumination, and afford means ol con- 
verting these fluctuations into oscillations of an electric current. 
If a hght ray and a selenium cell be simultaneously drawn 
along over opposite sides of a photographic plate, llie different 
shades of the various portions of the plate will result in con- 
tinuous oscillations of the current being produced in the cir- 
cuit of the cell This is a common feature with all the sending 
devices used in the instruments of this class. The current 
oscillations are made to act on the receiving apparatus, which 
will reconvert them in turn into fluctuations of light. The 
design of the receiving apparatus has hitherto been the weak 
point with all these systems, because the electric currents 
transmitted are so Aery small. Hut a satisfactory solution of 
the difficulties so far met with seems to be aflorded 
apparatus of I'rofessor Arthur Korn. 
presented before the French Academy 



by the teleoptical 
^Iunich, as recent! v 
of Sciences. 

While engaged in investigating the radiations given off by 
the electrodes of a tube exhausted to a pressure ranging be- 
tween 0-2 and 2 mill, as Hertzian vibrations were applied to 
the electrodes. Professor Korn noticed the extreme seubitive- 
ness with which these radiations would react on small altera- 
tions in the circuit. This sensitiveness suggested a possible 
utilisation of those radiations which were photographically 
most efficient, in connection with a method of electrical tele- 
photography. 

The apparatus, based on the above principle, is shown in 
fig. 1. 

The photographic film a uf the receiver rotates in front of a 
small window c (0-25 mm x 0-25 mm) in an exhausted tube /), 
like a roller, in front of the \ibratiug membrane ot a phono- 



graph. The surface of the tube is coated with black paper 
and tin-toil, lea-i-ing only the window. By means of high fre- 
quency currents (Tesla currents), luminous radiations may be 
produced inside the tube, and these, after passing through the 
small window, will make photographic impressions on the sen- 
sitive film. The latter is moved synchronously with the image- 
holder A of thesending-apparatus(afilm bearing the photograph 
to be transmitted wound on a glass cylinder), which is traversed 
by a very thin beam of light B C D while passing, line per line, 
before a selenium cell D placed inside the cylinder. .According 
to the different shades in the photograph transmitted, thesele- 



SoKlif of 

Light 




'SjjtA I 




Gxj^^acciXXf 



Fig. 



nium will receive more or less light, while an electric current, 
passing through the selenium D and the telegraphic wire F up 
to the recei\'ing apparatus, will undergo corresponding varia- 
tions of intensity, thereby regulating the intensity of the 
radiations of the receiving tube. This is provided for in the 
following way: The active electrode e of the tube being con- 
nected to one of the poles />, of the secondary coil of a Tesla 
apparatus, by inserting fields of sparks formed by the points 




Original Photograph. 




Transmitted Photograph. ^ .» 

nil, uij, of a galvaifometer needle / and two fixed points", fj, L, 
the intensity of the radiations given off by the tube will be 
more or less great, according to the distances nij fj and m, 
and (2, which are variable along w-ith the transmitted currents 
passing through the galvanometer i'. By the use of this 
arrangement, a means is afforded of making the intensity of 
the radiations of the receiving tube correspond with the in- 
tensity of the light striking the selenium of the sending- 
apparatus, thus reproducing line per line of the original photo- 
graph. 



April, 1904.1 



Tlu 



KNOWLEDGl*: \- SCIENTIFIC NEWS. 



57 



well. 



i.ij lui- Litciiii may. as wen. serve as a 
telautographical recciviiif;-apparatu:s. i.e. an apparatus for re- 
producing handwriting, drawinsr. &c.. at groat distances. In 
this case, only sonic ver\' slight alterations will liave to be 
made, and .i BakewcllCaselli transmitter used. The 
speed attained is relatively very high. It has been loinid 
possible to reproduce from tueiitv to fortv words in the 




Orig:inal Photograph. 

original handwriting iu the course of \.hu-e minutes, and in th< 
case of shorthand much higher speeds may be arrived .it. 
The transmis.sion of photographs, of course, is slower, princi- 
pally on account of a certain inertia of the selenium. Tin- 
progress lately made in connection with the construction of 
seleniimi cells', however, makes much higher speeds very prob- 
able. The time at present required for telepholographing a 
portrait is about half-an-hour. 




Transmitled Photograpli. 

Figs. 2 and 3 show the telegraphic reproduction of a photo- 
graph and a telautographic specimen respectively. The in- 
ventor wishes us to state that part of the imperfections of tlie 
photo, especially the stripes, is due to the e.xperiments having 
been made in the Physical Laborator\- of the Munich Univer- 
sity, where the pressure of the battery and, accordingly, the 
intensity of the source of light, would undergo frequent fluctua- 
tions. 



Modern Views of 
CKemistry. 

By II. J. II. l-E.MON, l-'.K.S. 

In our last coiiunimiiation \\c indicated \er\ Ijrieth', in 
outline, the nature ol the ionic-dissuciatiiui Ii\ polhesis, 
and mentioned Slime of the expeiiniental fads upon wbicli 
it is basi'd ; we propose now to ^i\e a few illustr.il ions oi 
the manner in, which the lupothesis li;is been applied to 
the explanatioir or inlerpret.ilioii ol sonic well known 
chemical and physical laiis. 

\\ hat is an ;u'id r' l'!\ei\one who is al all ai(|uamled 
with the cleinenlar\ huts ol cheniislrx has a lairh clear 
conception in his own mind what the term implies, but 
attempts to frame an exact definition .are not always 
satisfactory. If an acid is " an\' liydroi^eii compound 
which can exclKuii.j(; its liy(ir<)<ien, wholly or [lartly, for a 
metal when the latter is presentetl to it In llie form of a 
hydroxide," we must include as acids substances suih as 
zinc hydroxide and aluminium hydroxide, the distinction 
between acid and base heiny relative rather than .abso- 
lute. It was at one lime proposed lO' restrict the term 
" true acid " to a. c,om|)oiui(l which can behave in the 
abo\e manner even in presence of much water, and such 
a restriction woidd, it is true, exclude substances like 
zinc hydroxide, but it would al.soi exclude some com- 
[loimds like silicic acid which are looked upon as acids. 
Other definitions, such .is " a salt of hydrogen," " a 
compound which can evolve water by its action, 011 
caustic potash," or " a compound of hydrofjen with an 
elect ro-ne£^ative element or group, ' ("an generally b(^ 
foimd f;uilt with, and there is often a tendency to define 
the terms " acid," '' salt," " base " in a circle. 

The ionic-dissociation hypothesis now comes to the 
rescue with an elegant and .simple definition. ,\n acid, 
it says, is :\ ccuiipoimd whose aqueous solution contains 
free hydrogen ions. \\'hat we call acidity or acid-pro- 
perty in a solution is due to these ions, and is more prf>- 
noiinced as their concentration is greater, /.(■., the more 
there are in a gi\en \-olunie. A base, on the other li.uid, 
is a compound wlio.se aqueous solution conlains Irec 
Indroxvl (() II) ions, and when an acid neutralises a 
base the only change which takes place (provided the 
solution is dilute and the acid and base are " strong ") is 
the union of the free hxdroxyl and hydrogen ions to 
form water. It will beobser\ed that, according to this 
conception of the m.itter, neither the metal or acid 
radicle takes any part in the change ; they remain as 
free ions throughout — 

H + K + M + O H =M -f- R -f- 11 H 

(where K is the acid radicle and M the metal). 

It must not be forgotten that the older definitioiis 
alluded to above are practical ones, whei^eas thi.s ionic 
definition depends entirely upon hypothesis ; the latter, 
however, affords a remarkably simple explanation of 
many well-known facts. When, for example, equivalent 
weights of strong acids (say, hydrochloric or nitric) 
neutr.-ilise strong bases (say, caustic potash or soda), the 
quantitv of heat evolved is always the same. This fact 
is easilv understood on the above supposition, since in 
each case the only change in the arrangement is the 
union of hvdroxyl with hydrogen. 

If the ;icid or base, or both, are not " strong,'' the heat 
change on neutralisation w ill be different from that in the 
previous case. Thif. is explained by saying that the 
weaker acids and bases arc not entirely in a state of 



^8 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 19O4. 



" ionisation " or dissDciation to begin with, and require 
to be further broken up bsfore the hydrogen and hydroxyl 
can combine. 

What exactly is to be understood by the strength of an 
acid or a base was for a long time the subject of dispute. 
It used to be said that sulphuric acid was stronger than 
hydrochloric or nitric acids, because it " turned them 
out" from their combinations with bases. Sodium nitrate, 
for example, when distilled with sulphuric acid, gives 
sodium sulphate and free nitric acid. The test of strength, 
however, when applied in this manner, is not legitimate, 
since the nitric acid is not given a fair chance ; it is re- 
moved from the sphere of action by vaporisation. A 
much more rational way of arranging the encounter 
was that devised by Thomsen when he mixed, in 
dilute solution, one eijuivalent weight of each acid 
with one equivalent weight of base. Here there is in- 
sufficient base to satisfy both acids, and all the substances 
concerned, before and after the action, remain dissolved 
together without any removal. The two acids then strive 
for the base, and the one which gets most of it is the 
" strongest." In this way it is possible to arrange the 
acids in the order of their "strength," and experiment 
showed that hydrochloric and nitric acids head the list in 
such an arrangement. 

Sulphuric acid proves to be only about half as strong 
as nitric or hydrochloric acids— a result altogether at 
variance with the older ideas. 

The problem has been attacked also from various 

other points of view : it is known, for example, that the 

salts of weak acids or weak bases may undergo what is 

called hydrolysis in aqueous solution, that is to say that 

Salt + water = acid + base. 

Such an action can easily be shown in the case of 
ferric chloride or sodium borate. It was proposed, there- 
fore, to classify acids as weaker or stronger accordmg to 
the extent to which their salts were " hydrolysed " by 
water under similar conditions. 

Again, there are many chemical changes which are 
found to be greatly accelerated by the presence of acids, 
and if these changes happen to be sufficiently slow to 
enable one to map out the rate of change, it is possible 
to compare the influence of different acids. Results 
obtained in such ways agree, on the whole, remarkably 
well with the order of "strength" as measured by the 
"stri\ing for base " method. 

The electric conductivity again was found to be better 
for the stronger acid ; and the same is true with regard to 
the deviation from the " normal " osmotic pressure abo\e 
referred to (Article I.). Such observations were largely 
instrumental in leading up to the new theory. If one 
" believes in ions,"'^ it is a comparatively simple matter 
to explain, in terms of the hypothesis, what is meant 
by the " strength " of an acid. The strongest acids, like 
nitric and hydrochloric acids, undergo complete, or nearly 
complete, ionisation when dissolved in a moderate volume 
of water, whereas the weaker acids, like acetic or hydro- 
fluoric acids, are ionised to a less extent. In other 
words, a moderately diluted solution of hydrochloric acid 
contains a (relatively) large number of free hydrogen ions 
in a given volume, and an equivalent quantity of acetic 
acid contained in the same volume gives rise to (rela- 
tively) few free hydrogen ions. 

But ionisation increases as dilution increases, so that 
we arrive at the conclusion, which sounds paradoxical at 



first, that when their aqueous solutions are infinitely 
diluted all acids would be equally " strong " \ 

The strength of an acid, then, depends, according to 
these ideas, upon the concentration of the free hydrogen 
ions which is attained when an equivalent weight of the 
acid is dissolved in water and the solution made up to a 
given volume. But how are we going to measure this, 
or compare it, say, in the case of two given acids ? 

The complete explanation of the way in which this can 
be done would perhaps be out of place in a brief sketch 
like the present one; we will merely attempt here to give 
a very rough indication of the principle. 

The electric conductivity of an acid in solution depends 
upon the number of free ions present in a given volume 
and upon the speed with which they move. If we 
determine (directly or indirectly) the molecular con- 
ductivity of a given acid (i) when the solution is 
moderately dilute, and again (2) when it is infinitely 
dilute, it can easily be shown that the first number 
divided by the second will tell us the extent to which the 
acid is ionised in the moderately dilute solution. We 
can then make similar experiments with other acids 
under the same conditions, and so compare the extent to 
which each is ionised. Assuming for simplicity that 
each acid splits up into two ions, one of w hich, of course, 
is hydrogen, it is evident that the one which is most 
ionised is the strongest under the given conditions, i.e., 
there will be more free hydrogen ions in a given volume 
of solution. 

The extent of ionisation of the acid can also be arrived 
at from other considerations, such as the deviation from 
the normal osmotic pressure (see Article I.); but the 
electric conductivity method is the most generally applic- 
able. 



The Problem of Cancer 



By Felix Oswald, B.A., B.Sc. 



• At the present time il is well to look upon this ionic explana- 
tion as a very efficient and complete working hypothesis, and not 
to regard it, as is often done, in the light of a creed or dogma. 



The failure of bacteriologists to discover a cancer- 
bacillus has facilitated future investigation regarding 
a probable cure for cancer by narrowing the issue 
and disposing of a fruitless line of research. On the 
other hand, the recent important discovery of Professor 
Farmer and his colleagues, that cancer-cells agree with 
reproductive cells in only containing half the number of 
chromosomes in the nucleus after nuclear division, re- 
calls the experiments of Galeotti,'" in 1693, with regard 
to the unsymmetrical and irregular nuclear division in 
cancer-cells. It appears probable that the efficacious 
preventive treatment of cancer is to be sought in the 
direction indicated by these experiments, which have 
hardly received the attention they deserve. Briefly 
stated, Galeotti treated acti\ely dividing, epithelial cells 
of salamanders with dilute solutions of drugs such as 
antipyrin, chloral, quinine, cocaine, nicotine, potassium 
iodide, &c. The action of these substances caused 
asymmetrical and tripolar division of the nucleus, 
exactly similar — as the accompanying figures will show 
— to the asymmetrical and tripolar division which takes 
place in cancer-cells in a human subject. The remark- 
able similarity between these pathological occurrences 



* Beitr. zur patholog. .\natomie und zur allgem. Pathologie, 
XIV. 2 ; Jena, 1S93- 



April, 1904. 



KNOWLEDGE .^ SCIENTIFIC NEWS. 



59 



points to the inevitabu .:: .usion that <a:: ^: 
primarily due to an irritant poisonous substance, that 
such substance is secreted, in a spot liable to disease, 
e.g., in glandular tissue, and that the blood is unable to 
carry off or neiitralise the deleterious matter. 

The problem of an ultimate cure for cancer would 
seem, therefore, to lie in the chemist's sphere rather than 
the surireon's, li:.. firstly, in the careful analysis of fresh 
cancerous tissue, and the isolation of the irritant prin- 
ciple; and, secondly, in thediscoxery of an antidote to be 
injected into the system just as antitoxin is injected for 
diphtheria, to assist the blood in its function of eliminating 
the injurious substance. It is a suggestive fact that antago- 
nistic drugs are known to the substances which Galeotti 
used in creating the pathological nuclear divisions so 





A 





B 



II 



A, — Epithelial Cells of Salamander, showing (i.^ iin.symmetrical 
nuclear division after treatment with 0*05 per cent, anti'pyrin solu- 
tion; 'ii.) tripolar di\ision after treatment with o'5 percent, potassium 
iodide solution. B. — Human Cancer Cells, showing; <i.i unsymmetrical, 
and ii.) tripolar nuclear division. [Both after Galeotti 



similar to those of cancerous tissue, e.g., strychnine is 
antagonistic not only to nicotine, but to chloral, to which 
atropine also shows antagonism. 

The similarity between cancer-cells and reproductive 
cells in containing only half the usual number of chromo- 
somes compared to normal somatic cells, and the further 
discovery that the nuclei of all the cells in the sexual 
generation (prothallus) of a fern show this reduction, 
would seem to indicate that the occurrence of cancer- 
cells in the bodies of man and higher animals shows a 
tendency to a reversion to the remote state of things 
when every single cell of the reproductive generation 
partook of this peculiarity of the reproductive cell. It 
•would be interesting in this respect to ascertain whether 
the cells of the sexual generation in lowly creatures of 
the animal kingdom, such as liver-flukes, jelly-fish 
(Aiirelta), and some Tunicates (Salpa), &c., which exhibit 
an alternation of sexual and asexual generations, show 
the same condition as the fern prothallus in the vegetable 
kingdom. 



Rare Living Animals 
in London. 



By P. L. ScL.\TER, F.R.S. 



I \ the annual reports of the Zoological Society of London 
will always be found a section containing a list of the 
species new to the collection exhibited during the pre- 
ceding year, and though, as we all know, it is continually 
becoming more difficult to find " something new " in any 
class of objects, it will be seen, on reference to the 
reports, that even in the most recent years the list of 
novelties is by no means a short one. There are, in fact, 
always a considerable numlier of recent additions to the 
Zoological Society's living collection of mucli interest, 
and well worthy of representation by the facile fingers of 
the artist, which we believe to be a much more generally 
effective way of bringing the points of their shape and 
structure into notice than the cheaper and more fashion- 
,ible photographs of the present day. 

It is with great pleasure, therefore, thai 1 ha\e under- 
taken to write a few remarks on some of the rare and 
interesting animals in the Regent's Park that have lately 
formed the subjects of Mr. Goodchild's skilful pencil. 

1. The Thylacine. 

(Thylaciniis cyiwirphaliis. ) 

In the late Sir William Flower's excellent " Introduc- 
tion to the Study of Mammals " the threefold division of 
that order, originally proposed by Blainville, into " Or- 
nithodelphia," " Didelphia," and " Monodelphia" is fully 
maintained, although, for good reasons, Huxley's change 
of these names into " Prototheria," " Metatheria," and 
" Eutheria " is adopted, as being " far less open to objec- 
tion." The Metatheria, as Flower points out, are repre- 
sented in the present epoch by numerous species which 
offer considerable dixersities in appearance, in structure 
and in habits, although they all agree in many anatomical 
and physiological characters which gi\e them an in- 
termediate position between the Prototheria and the 
Eutheria. The most important of the latter set of 
characters is that the young of the Metatheria are brought 
forth in a rudimentary condition, and are nourished by 
milk injected into their mouths from the maternal 
mamma;, to which they are firmly attached for some time 
after their birth. During this process the young, in 
nearly all cases, are sheltered in an abdominal pouch or 
marsupium, whence the Metatheria have received the 
more familiar name of " Marsupials." 

The Marsupials then, as we will call them, are usually 
divided into two sections, the Diprotodonts and the Poly- 
protodonts. Of the former of these, which with a few 
unimportant exceptions are vegetable feeders, the best 
known are the kangaroos of Australia and the adjacent 
islands, while of the Polyprotodonts, which are carnivo- 
rous and insectivorous, the finest and largest representa- 
tive now living on the earth's surface is the Thylacine of 
Tasmania, the animal represented in the accompanying 
drawing. 

On first seeing the Thylacine alive the uninformed 
spectator would naturally take it for a dog or a wolf. 
And indeed in general external appearance the Thylacine 
is excessively like one of these animals, but it is, never- 
theless, undoubtedly a Marsupial in every essential part 
of its structure, and like most other members of th«5 



6o 



KNOWLEDGE & vSCIENTIFIC NEWS. 



[April, 1904. 



Metatherian group carries its new-born young in an 
abdominal pouch. It is also at once distinguishable from 
a wolf by its long, tapering, and thinly-haired tail, as is 
well shown in our picture, and by the curious transverse 
stripes on the bark, wliich are very prominent in the 
living animal. 

The Thylacine is a native of Tasmania, and is not 
found in any other part of the world, although in a former 
geological epoch an allied form, which has been named 
Thylacinus speUnis by Professor Owen, existed in the 
adjacent parts of Australia. In Tasmania the Thylacine 



is the only specimen of the Thylacine now alive in 
P-urope. 

The first living Thylacines ever received by the Zoo- 
logical Society were a young pair presented by their 
Corresponding Member, Mr. Roland Gunn, of Launces- 
ton, in 1849. They had been captured in snares on the 
upper branches of St. Patrick's River, about thirty miles 
N.E. of Launceston, and lived many years in the Regent's 
Park. The same generous friend, learning that these 
animals were no longer alive, sent a second pair in 1863, 
which likewise did well in the Society's Gardens. Thyla- 




Tlie Thylacine {Tliyhimiin ninurf-luiliis). 



is said to be popularly known as the " tiger " or 
" hyaena," from its rapacious habits, but is also often 
called, more appropriately, the " Tasmanian wolf." 

In former days, when Tasmania was first peopled by 
luiropeans, the Thylacine was common in all the rocky 
and mountainous districts of the island, and at that time 
found an abundant supply of food in the native kangaroos 
and bandicoots. But when sheep were introduced into 
the Colony, and bred in large numbers, the Thylacine 
soon learned to attack the sheepfolds, and consecjuently 
became an object of persecution to the Tasmanian shep- 
herds, whose fierce hostility has now brought it to the 
verge of extinction. Of late years, indeed, very few 
living specimens of it have reached Europe, and the 
Zoological Society is fortunate in having secured the fine 
young male example now figured, which was obtained 
by purchase in March, 1902. So far as 1 know, this 



cines in captivity are very active in their mo\'ements 
when excited, but somewhat nocturnal in their habits. 
They are usuall)' fed on nuitton. 

>^ "^i -"^ ^^ "^i 

Blake's Historica.1 Cha-rts. 



Mh. ^\"ILLI.\^r Pii.AKK h.is compiled a series of Historical 
Charts, designed to show in a sort of bird's-eye view the 
course of Enslish IIistor\- in different year periods. Chart 
No. I. gives a general vieu of English History from 1066 to 
igoa. Chart No. H., intended to be used with the other 
Charts, and a most useful supplement to them, gives contem- 
porary European rulers from 1066 to igo2. Succeeding 
Charts cover various pliases of English History from the 
Roman Dominion in Britain to the reign of Queen Victoria. 
The Charts have been very carefully compiled at the cost of 
immense labour, and are designed for the use both of students 
and teachers. 



April, 1904..] 



KNOWLEDGE & SCIENTIFIC NEWS. 



fir 



The Ancestry of the 
CaLrnivoraL. 

By K. LvnrKKKK. 

CoMTAKi;!! with the more advanced types of ungulate, or 
hoofed, mammals, such as the horse, the camel, and the 
true ruminants, all the Camivora are in many respects 
much less specialised animals, more especially as regards 
the structure of their limbs. By this I mean that 
although all of them are thoroughly adapted to their own 
special mode of life, while in many instances they are 
some of the most active, most highly organised, and 
most intelligent of all animals, yet they depart much less 
widely from the primitive type of mammals in general 
than is the case with the more specialised ungulates, or 
indeed, than ungulates collectively. In none of them 
for instance, docs the number of toes on each foot ever 
fall below four, while in some cases the typical five digits 
are retained in at least one pair of feet. Then again, 
although in the members of the cat tribe specialisation is 
displayed by the development of sheaths for tlie protec- 
tion of the sharp and sickle like claws, the terminal joints 
of the toes are always of the primitixe claw-like type 
the unguiculate form, as it is termed by naturalists, and 
never make any approacli to either nails or hoofs. More- 
over, all the Carni\ora are characterised by the absence 
of that tendency to a reduction of the number of the 
bones in the limbs by the fusion of two together and the 
disappearance of others, which, as we ha\e seen, form 
sucli striking features in the evolution of the more 
specialised t)pes of hoofed animals. .Such consolidations 
and reductions in the bony framework are indeed striitly 
correlated with and necessary to the develipment of a 
small number of hoofs on each foot, and are, therefore, 
from the very nature of the case, conspicuous by their 
absence in the Carnivora. Indeed, if we except the 
frequent disappearance of the collar-bones, or clavicles, 
the skeleton shows none of that anialf;atnation or loss 
of some of its elenients, coupled with the e.\cessi\e 
development of others, which are such noticeable features 
in the more specialised ungulates. 

Then, again, the teeth of the Carnivora, though ad- 
mirably adapted to the special needs of their owners, are 
much less widely removed in structure from the primitive, 
or generalised, mammalian than are those of the higher 
hoofed mammals. The cheek-teeth, for instance, never 
display that heightening or broadening of the crown, 
coupled with those deep infoldings of the grinding surface, 
seen in the molars of the horse and the ox. Moreover, 
unlike what so frequently takes place in the ungulates, 
the front teeth are always well developed, and rarely fall 
below the typical mammalian number of three pairs of 
incisors and one of canines, or tusks, in each jaw. In- 
deed, when a reduction in the number of the teeth does 
take place, as in the cats, whose short jaws do not leave 
room for the full complement, such reduction takes place 
at the hind end of the series. 

Among living Carnivora the group which is in the 
whole the most generalised and the least widely removed 
from the primitive ancestral type is that of the dogs — 
including under this name not only the animals properly 
so called, but likewise wolves, jackals, foxes, etc. To 
enter into a consideration of the structure of the skeleton 
would obviously be an impossibiliiy on this occasion, and 
it must accordingly suffice to mention that while thetypical 
number of five toes are retained in the fore-foot of nearly 
all members of the group, in the hind foot there are only 



four ; and that although collar-bones arc developed, yet 
they are reduced to mere rudiments. One other impor- 
tant circumstance in coniU'Vj^u-^wilii i'kirJi^rt'-^^ iiiusl, 
however, be noticed. If tno ikjVu"^ (TT Uu; wnsfTor car- 
pus, of a dog be compared wYl'l^'^Wifr? ^ mau or of 

;h:fr'^u;;;:r^r::::«sSK>^^ 

elements. This is due to tTie fusion of iwi of the bones, 
the scaphoid and lunar ; dKP tAiki)iHid£)^clI^Jhtliteristic 
of all modern Carnivora, in which the coni])nund bone is 
known as the scapho-lunar. 

One other feature — and this connected with the denti- 
tion — is very characteristic of modern land Carnivora. 
In the skull of a cat, dog, or wolf (fig. 1 ) it is well known 
that one pair of teeth in the side of ea( ii jaw dilier 
markedly in size and structure from all the rest, the upper 
biting upon the lower pair with a more or less scissor- 
like action. It is with this pair of specialised teeth that 
a tiger or a lion cuts up the masses of flesh torn from its 
prey into convenient lengths for swallowing ; and these 
formidable weapons are consequently known as the car- 
nassial, or flesh, teeth. Curiously enough, these teeth 
do not serially correspond with one another. It will be 
seen, for instance, both in fitfure i ;in(l fi<rure 2, that while 



r^^ 




K^H##fV- 




Fig. 



-5ide view o( skull of Wolfto show the carnassial teelh. 



the upper carnassial is the fourth from the tusk, the cor- 
responding lower tooth is the fifth from the latter; liotli 
the species in the two illustrations referred to ha\-ing the 
full typical series of anterior cheek-teeth. Nor ir, this all, 
for whereas the upper carnassial has no deciduous pre- 
decessor (" baby-tooth "), the corresponding lower tooth 
succeeds a deciduous baby- tooth. Conscrjuently, the 
upper carnassial — to employ technical language- belongs 
to the premolar series, while the lower carnassial is one 
of the true molars. 

Now, when we find two organs which do not serially 
correspond with one anotlier, modified for some particular 
function, it may be at once taken for granted that this is 
a highly specialised condition which did not obtain in 
the beginning ; and this we shall find to hold good in the 
case of the (Carnivora. 

hVom the general presence of this peculiar type of den- 
tition, all the modern Carnivora, together with many of 
their extinct relatives, are collectively known as theCar- 
nassidentia. Not that it must be assumed that this 
feature is common to them all. In the bears, for in- 
stance, the carnassials, although still displaying traces of 
the characteristic structure, have become comparatively 
small and weak teeth, much smaller than the grinding 
molars behind. And this degeneration (for by means of 
fossil forms the feeble carnassials of the bears can be traced 



62 



KNOWLEDGE & SCIENTIFIC NEWS. 



April, 1904. 



into the fully-developed ones of the dogs) may be 
explained by the nature of the food of bears, which does 
not require the action of scissor-like teeth. 

.\t(ain, in the seals and walruses there is no trace of a 
differentiated pair of carnassial teeth ; such a type of 
dentition being unnecessary to animals living on a fish 
diet. In the case of the eared seals and walruses, there 
is little doubt that the absence of differentiated carnas- 
sials is due to degeneration, these creatures being 
apparently related to the bears. The case of the true, or 
earless, seals is more uncertain : and it has been sug- 
gested that these creatures inherit their distinctive type 
of dentition direct from an extinct group referred to 
below. .Vgainst this is the circumstance that they 
possess the compound semilunar bone in the wrist, which, 
on the above view, would imply the fusion of the two 
elements entering into its composition in two independent 
instances. 

Reverting to the existing members of the dog tribe, it 
will be noticed that the skull (fig. i) is characterised by 
its elongated form and relatively large brain-cavity. The 
teeth fall short of the typical mammalian number of 44 
only by a single pair — namely, the last pair of molars in 
the upper jaw. Consequently there are only two pairs 
of teeth behind the upper carnassial. In the lower jaw 
the last molar is \ery small, and evidently on the point 
of disappearance. As regards the other teeth, it must 
suffice to mention that the carnassials are strongly de- 
veloped and possess a perfect shearing action, the lower 
one having a large tubercular portion for masticating 
behind the cutting blade ; and that most of the premolars 
(other than the upper carnassial) carry accessory cusps 
on either side of the main cone. It may be added that 
all the existing members of the fatnily are digitigrade — 
that is to say, they walk on their toes instead of on the 
sole of the foot, which is raised above the ground and 
covered with hair. 

A large number of extinct dog-like animals have left 
their remains in the Tertiary strata of both Europe and 
North America ; those from the newer formations being 
nearly allied to existing types, while the older forms are 
more or less decidedly different. One of the most im- 
portant of these extinct types is the Oligocene and 
Miocene genus Cynodictis, which is without much doubt 
the ancestral type of the true dogs (diiiis) of the present 
day. Although generally having the same dental formula 
as the latter, Cynodictis exhibits distinct signs of affinity 
with the ancestors of the civets. On somewhat the same 
platform of evolution as Cynodictis is the North American 
Daphanus, of which the skull is shown in fig. 2. In this 
animal it will be seen that a small third upper molar 
(the third tooth behind the carnassial) is retained, thus 




bringing up the number of the teeth to the typical 44. 
In general characters, the dentition is very similar 
to that of modern dogs, but there are fewer accessory 
cusps to the premolars, and the posterior portion of the 
lower carnassial is adapted for cutting, instead of for 
grinding. The dogs of this genus are further remarkable 
for the shortness of their JAws ; and it has accordingly 
been thought that they may ha\-e been the ancestors of 
the modern wild dogs (Cyon) of Asia. 

Great interest attaches to another type of Tertiary dog, 
the A inpliicyon of the Miocene and Oligocene strata of both 
hemispheres, some of the species of which attained 
dimensions rivalling those of a bear. This interest is 
due to the fact that these giant dogs, which had 44 teeth, 
and partially plantigrade feet, were the actual ancestors 
of the modern bears, with which they are connected by 
certain extinct genera. We thus establish the derivation 
of bears from dogs of a generalised type. 

All the foregoing extinct general types of dogs may, 
however, themselves be apparently derived from a still more 
generalised form from the Middle, or Bridger, Eocene of 
North .'\merica, known as Vulpavus. In this animal, 
wnich can only be tentatively included in the dog family, 
the skull (fig. 3) is characterised by its long and narrow 



Fiit. 2.— Skull of iMiili.Tiuit, a primitive Dog from the Middle Eocene 
strata of the United 5tate.s, with a crown view of first and second 
lower molars. 'After Dr. Wortman.) 




Fig. 3.— Skull of Vulpai'ui, an ancestral type of Dog from the 
Bridger Eocene. (After Wortman.) 

form, and the small size of the brain-cavity. The teeth, 
of which there are 44, are of a decidedly dog-like type, but 
the outer front angles of the upper molars assume a cutting 
character, and the bkide of the lower carnassial is much 
taller and narrower, and also more obliquely placed, 
than in the dogs, while the second and third lower 
molars, although much smaller, present a decided re- 
semblance to the carnassial. Moreover, the lower pre- 
molars have large fore-and-aft cusps, differing in character 
from those of the true dogs. Unfortunately, the struc- 
ture of the wrist is unknown, but it is quite possible the 
scaphoid and lunar bones may be separate. The hind 
as well as the fore feet were five-toed. 

More or less nearly allied to Vulpavus are certain other 
Lower Tertiary Carnivora, exemplified by the genus 
Vivevravus, which are regarded as forming the most 
primitive family of Carnassidents at present known. 
They have five-toed feet, with the scaphoid and lunar 
of the carpus separate; and the dentition, in which the 
number of the teeth may be either 44 or 40, difters 
from that of Vulpavus by minute details, to which it is 
impossible to refer on this occasion. In certain numbers 
of the family, such as Oijdectes, the last two lower 
molars are exceedingly like the carnassial, and have 
their crowns but little lower, although these teeth retain 
the essential carnassident feature of being smaller than 
the latter. In other respects, the dentition of these 
primitive forms comes very close to that of the under- 
mentioned creodonts, with which the Viverravida also 



April, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



63 



agree in their divided scaphoid and lunar. As indi- 
cated by the name of the typical ijcnus, the ]'ii(ii(iviJu- 
are re,t;arJed by .\nierican pala-ontoloi^ists as the ances- 
tors of the ci\ets (r/rvM/iL-) of the old world; and it is 
not improbable that they were likewise ancestral to the 
primitive dogs. If it be added that there is evidence to 
show that the members of the weasel tribe are also 
sprung from a more or less nearly allied Eocene group, 
we shall have accounted for the origin of four of the 
most important families of existing land Carnivora, 
namely dogs, bears, civets, and weasels. As regards 
hya?nas, there is little doubt that they are closely related 
to civets, with which they appear to be connected by a 
number of extinct forms, such as IitHI:eiiiiw. 

Leaving the raccoon family alone, it may be added 
that there is still some degree of uncertainty with regard 
to the origin of the cats (Felida-). Unless, l)owe\ er, they 
trace their origin direct to the undermentioned creoclonts, 
there seems to be considerable probability that they 
are derived from the imperfectly known family of primi- 
tive camassidents termed PaLconklidte, all the members 
of which are characterised by their short jaws and cat-like 
dentition. In the typical Palteonictis, which dates from the 
\\"asatch, or Lower, Eocene, the carnassials are somewhat 
imperfectly differentiated from the other teeth ; but in 
.Ulurotherium of the Bridger they become well characterised 

Having thus traced, more or less definitely, most of 
the principal families of existing land Carnivora to 
generalised forms which are evidently on the bordeiland 
between the Carnassidentia and some more primitive 
type of Carnivora, we have to turn our attention to what 
is known with regard to the latter. 




WU*V^ 



Fig. 4.— 5kull of Sinop.:, a North American Creodont. (After Wortman.) 

Such primitive type is represented by the Eocene and 
Oligocene Carnivora collectively known as Crecdontia, 
of which the American'5(H(?/'a or Stypolophus" (fig. 4) and 
the European Hycenodon and Pterodon (fig. 5) are well- 
known representatives. In addition to other features 
which cannot be noted here, these creodonts are collec- 
tively characterised by three long, narrow, small-brained 
skulls, by the fact that the scaphoid and lunar of the 
wrist are usually distinct, and, above all, by the non- 
development of a pair of differentiated carnassial teeth. 
In place of these, the lower jaw (fig. 5) has all the three 
molars of a cutting type ()«', )«-', w;^) ; and it will be 
further noticed that these teeth differ from the corre- 
sponding teeth of a carnassident by the circumstance 
that they increase in size from the first to the third, 
instead of decreasing. These animals all have five- toed 
feet, in which the thumb and the first toe may he 
opposable to the other digits. 

Unless these creodonts have given rise to the true seals 
of the present day, they seem all to have died out during 
the Tertiary period without leaving any descendants. 
Moreover, they appear to have been derived from some 
still more primitive stock independently of the carnas- 



* Represented in Europe by ihe closely allied Cynohyctnodon. 



sidents, with the earlier forms of which latter they were, 
however, evidently allied. In other words, camassidents 
and creodonts appear to be (h\eri;ing branches from a 
single primitive stock-, which proh.ibiy li\t\l iluring the 
Secondary, or Mesozoic, epoch. 



^'^k: AJ;:-d'%f 









FiK. ;;.• 



-Lower Jaws of Creodonts and Marsupials. 

2 PtfTudon, 3 H(trU;i'i lift, 4 TiiijlacintiH. 



What were these Mesozoic ancestors, is the next ques- 
tion which presents itself. 

.V comparison of the lower javvs of the creodont 
Hyctnodon and Pterodon with that of the marsupial 1 hyla- 
cinus, as displayed in fig. 5, shows at a glance that the 
dentition in all three is of the same generalised type ; 
this being especially indicated by the form and relative 
dimensions of the three molars. It is true, indeed, that 
in the marsupial there appear to be four of these teeth ; 
but this is due to the fact that the tooth in advance of 
these (m.p. 4) is a persistent milk-tooth, which is not 
replaced, as in the creodonts, by a permanent premolar 
(pp. 4). Certain South American extinct types such as 
Borhyana (fig. 5 — 3) are intermediate in regard to the 
number of teeth replaced between creodonts and mar- 
supials, in Iho latter of which only one (pp. 3) is so 
changed, and it is consequently a difficult (juestion to say 
whether these South American forms .should be classed 
as creodonts or marsupials. 

Be this as it may, it is (juite evident that creodonts 
and marsupials are nearly related, and have probably 
both sprung from Mesozoic ancestors. The next ques- 
tion is whether these Mesozoic ancestors should be 
called creodonts or (in a wide sense) marsupials. Un- 
fortunately the degree of preservation of the compara- 
tively few and imperfect known remains is such as to 
preclude a definite answer being given to the ques- 
tion. Dr. Wortman, to whose opinion I attach great 
value, inclines to the belief that they were marsupials. 
Personally, basing my opinion on the restricted tooth- 



64 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 



change of the latter, I am more disposed to call the 
Mesozoic forms primitive creodonts, and to consider 
creodonts as the ancestors of marsupials, rather than 
vice vena. 

The whole question is, however, absolutely bristlint; 
with difficulties and uncertainties, and involves the dis- 
cussion of a number of technicalities which cannot 
possibly be touched upon here. 

With this, then, I must lea\e the subject, merely 
adding that after having traced the specialised modern 
Carnivora into early types closely allied to the primitive 
Creodontia, and ha\ing also pointed out the existence of 
a near affinity between the latter and the carnivorous 
marsupialia, the question naturally arises whether the 
middle Mesozoic mammalian forerunners of these groups 
may not themselves be the descendants of the carnivor- 
ous mammal-like reptiles (theriodonts) of the early part 
of the same epoch, which have a typical carni\orous 
type of dentition. If so, the dog and civets of our own 
day have a truly ancient pedigree. 



Is there Snow on the 
Moon ? 



A Study of the Lunar Apervrvirves. 



I5v E. Walter MArxL.F.R, F.R.A.S. 

Tin: principal object in the accompanying Plate, which is 
reproduced from one of the superb photographs taken by 
MM. Loewy and Puiseux, with the great equatorial 
coude of the Paris Observatorj', is the range of the 
lunar Apennmes, by far the grandest mountain 
chain upon the moon, and the one which, at first 
sight at least, most stronLrly resem- 
bles those of our own earth. It is 
shown in its entire length of more 
than 400 miles from the fine ring- 
plain Eratosthenes, in the extreme 
right-hand upper corner of the 
Plate, which forms the termination 
of the range to the south, down to 
the grand promontory of Mount 
Hadley, more than 15,000 feet in 
height, in which it ends towards 
the north. About halfway between 
the two extremities of the range is 
the magnificent headland of Mount 
lluyghens, according to Schmter 
nearly 21,000 feet in height, the 
highest summit on the moon with 
the exception of some of the peaks 
on the ramparts of the ring-plains 
of the south polar cap. A third 
great promontory. Mount Bradley, 
lies nearly midway between Mount 
Huyghens and Mount Iladley and 
reaches a height of about 16,000 ft. 
The highland region, of which 
the Apennines form the north- 
eastern face, is roughly triangular 
in shape. By far the loftiest and 
steepest face is that overlooking the 



great Mare Imbrium towards the east. The north-west- 
ern face looks over the Mare Serenitatis, whilst the Sinus 
.■Estuum and the Mare \'aporum bound the region on 
the south. 

The area of the Plate is not one which includesm any 
of the circular formations so typical of the moon, but 
some of those which are shown are very striking. Three 
great ring-plains are seen on the floor of the Mare Imbrium. 
These, in order of size, are Archimedes, the largest and 
most eastern, Aristilles, the most northern, and Autoly- 
cus, the smallest of the three, just opposite the broad 
gap which separates the Apennines from the Caucasus. 
On the opposite side of this opening, and slightly further 
from it, the celebrated crater Linne is seen as a small 
white spot on the floor of the Mare Serenitatis. Toward 
the extreme upper left-hand corner of the Plate, near the 
border of the same Mare, stands the bright crater Sul- 
picius Gallus, and amongst the actual highlands of the 
Apennines are the two craters Conon, just behind Mount 
Bradley, and Aratus, a little further north towards Mount 
Hadley. These seven are the most notable circular 
formations in the Plate. In general, the lunar mountains 
take the form of rings or polygons, as in the case of these 
se\en objects, and do not make continuous chains as on 
the earth. To this rule the Apennines constitute the 
most conspicuous exception, but a detailed exanrination 
of them shows that the differences between them and 
the great terrestrial ranges are numerous and significant. 

The first feature of the Apennine highlands to claim 
attention is the nearly triangular form of the area they 
cover. This is a necessary consequence of the roughly 
circular form of the great Maria which border them. 
Wherever we have a number of circular depressions con- 
tiguous to each other, the more elevated interstices must 
necessarily approximate to triangles. .And this being the 
case, it follows that the forms of the highlands ha\'e been 
determined by the Maria and not the reverse. In other 
words, the highlands existed first and acquired their 
present outlines through the later formation of the 
surroundinij Maria. 




Ma rr 
■ Ji'rriii/aiis 



Arc/ianedes 



Jristilles 



'KxowLKPi-.E A Scientific News." — .-Ifi.'.', />«'/. 



I- 
O 

CO 




■1S3M 



Aprii , 1904 ] 



KNOWLEDGE & SCIENTIFIC NEWS. 



r.^ 



The next feature to be noticed is the general slope of 
the repon. Towards the Mare Iinhriiun on the cast, 
the face presented by the Apennines is exceedingly bold 
and steep; towards the Mare Serenitatis an<l Mare 
\'ap)orum on the west and south the highlands sink 
down iiradmllv. 




Pijf. I.— Morning. 

The result of such a formation upon the earth would 
be obvious. There would be a deposition of moisture 
over the whole highland region, either in the form of 
snow or water, and this moisture would move downwards 
towards the plains either as streams or glaciers. lUit it 
would move with very different speed and different effects 
upon the two faces. On the steep escarpment facing east 




Fijf. 2. — Forenoon. 

neither water, snow, nor ice could rest. The moisture 
would be quickly thrown off, descending in waterfalls or 
avalanches down to the plains, and wearing away the 
cliff face into a great number of narrow gorges or gullies. 
The liebris would be deposited at the foot of the cliffs, 
and the torrents would car\e their way some distance 
into the plain, as a rule in a direction at right angles to 



the range, smoothing out and covering all irregularities 
which ran parallel thereto. What we actually see upon 
the photograph is as unlike this as could well be imagined. 
The liase of the range in the Mare Imbrium is confronted 
by a line of low hills, wrinkles as it were on the surface 
of the plain, suggesting by their parallelism to the range 




rijf. .?. Noon. J 

that no effecti\e amount of moisture, either as rain or 
snow, had been deposited on the eastern slopes nf the 
Apennines since the Mare Imbrium was formed. 

r)iit the main drainage of the region would be in the 
opposite direction, because the chief catchment area would 
be the broad gentle slope towards the west and south. 
Here the tendeury would lie for the moisture, whether it 




ri^. 4.— AUf rnoon. 

was in the form of ice or water, to unite small streams 
together to form larger ones. Important risers or glaciers 
would have their origin in this region, and would work 
their way downwards excavating broad valleys. The 
erosive effects, if not so rapid as on the east face, would, 
from the better presentment to us, be even more con- 
spicuous, and there should be no difficulty in detecting 



66 



KNOWLEDGE & SCIENTIFIC NEWS 



'April, 



1904. 



the deposit of alluvium at the mouths of the great water- 
courses. We do indeed find valleys and ra\ines on the 
western slopes, but these often are so blocked or show so 
many irregularities of level that they cannot be held to 
be water channels. If this was their original nature, then 
the more recent history of the moon must have entirely 
changed their appearance ; we see nothing to remind us 
of the characteristic arrangement of a drainage area on 
the earth. More than that, we find in the neighbourhood 
of Sulpicius Gallus a dark band parallel to the edge of 
the Mare Serenitatis, as if the Mare w-as actually deeper 
here than further out in the plain. Such a channel would 
have inevitably been filled up by the alluvium washed 
down by rivers draining the highland district. 

It is very instructive to watch the apparent changes 
produced in any region of the moon by the progress of 
the lunar day. The fi\e photographs of the regions of 
the Apennines shown in figs. 1-5 are reproduced from 
Professor W. H. Pickering's " Photographic Atlas of the 
Moon," noticed in the last number of " Knowledge," 
and will give some idea of the great value of this syste- 
matic mode of study which Professor Pickering has 




F'g.-5- — Evenin;?. 

carried out. It will be seen at once that the change in 
the lighting produces an immense change in the general 
appearance of the region. The five photographs we may 
describe for purposes of reference as showing the district 
at morning, forenoon, noon, afternoon, and evening ; 
descriptions which are only roughly correct, but which 
will suffice for reference. It will be seen at once that the 
appearance of relief vanishes almost entirely at noonday ; 
it increases directly in proportion to the obliqueness of 
the illumination, and is very marked in the last photo- 
graph of the series taken almost at sunset. The two 
great craters, Archimedes and Eratosthenes, are prac- 
tically lost at noon. At this time the brightest objects 
are the glittering peaks of the Apennine range, the rampart 
of Conon, and the white mantle surrounding Aratus. 
In early morning and late evening the gradual slopes of 
the highlands towards the west, and their steep declivi- 
ties towards the east, are the regions which respectively 
shine out most conspicuously. But it is the latter which 
are by far the most brilliant ; and, looking at the fifth 
photograph, there would seem not a little to justify Pro- 
fessor W. H. Pickering's description of them as snow 
covered. " Many of the higher summits of the Apen- 
nines," he writes, " are brilliant with snow, although the 



sun is just setting upon them, whilst the slopes of the 
intermediate valleys and of the foothills are dark." 

Professor Pickering's interpretation of the brilliancy of 
the eastern slopes of the Apennines involves several 
assumptions. He considers that the deposition of snow 
will vary on the moon according to the elevation of a 
district and according to its distance from the equator. 
But it should be borne in mind that elevation on the 
moon will not be nearly as effective in producing con- 
densation as on the earth. The action of gravity at the 
lunar surface is but one-sixth of what it is with us. This 
would have a two-fold effect. Whilst here w-e reach a 
region of half the surface pressure at a distance of three 
and a half miles, on the moon we should have to ascend 
more than twenty-one miles to obtain the same pro- 
portional diminution, whilst the feebleness of gravity 
would make any upward motion of the atmosphere ex- 
ceedingly slow. The cooling of an ascending current of 
air by expansion, here the most efficient cause of con- 
densation, would there be practically inoperative, and the 
great tenuity of the lunar atmosphere would tend in the 
same direction. There would scarcely be any perceptible 
difference in the readiness with which condensation 
would take place between the plains and the mountain 
summits. 

The comparison of the five pictures, too, does not sup- 
port the inference that the bright regions are snow- 
covered. The western gentle slopes are by no means so 
bright under their best illumination as the steep eastern 
escarpments are under theirs. Yet it is on the former that 
we should expect the snow to lie, whilst as they are best 
lighted by the morning sun, that is to say, just as they 
emerge from the long lunar night when the snow should 
be thickest, we should expect them to be far more fully 
covered, and therefore more brilliant than the steep 
eastern slopes could be at sunset, after having undergone 
the continued action of the sun during the whole length of 
the lunar day. The changes in illumination are indeed 
just what w-e might expect from the varying incidence of 
the solar rays, provided that there was some difference in 
the reflective power of the different surfaces. And in 
this case there is no difficulty in pointing out a sufficient 
cause for the steep slopes being more brilliant than the 
gentle. Mr. Davison (" Knowledge," December, i8g6, 
p. 278) pointed out that objects on a slope from, the mere 
effect of the expansion during the heat of the day and 
contraction under the cold of night, would steadily creep 
downwards. There would thus be a very slow but con- 
tinuous transference of free solid particles from the 
summits of the mountains towards the plains, uncovering 
fresh surfaces in the higher regions, and this creeping 
effect would necessarily be much more rapid on such 
steep declivities as the eastern face of the Apennines 
than on the gradual slopes towards the west. If then 
the very tenuous atmosphere which we may readily 
believe to exist upon the moon be capable of effecting 
some slight tarnishing or darkening effect in the course 
of centuries, or if the deposition of meteoric dust, which 
must be much the same as upon our earth, slowly coats 
our satellite with a thin dark veil, we shall find a sufficient 
explanation for the difference in albedo of the mountain 
peaks and of the great plains. 

This explanation is emphasised by the consideration 
of a point which Professor Pickering brings forward in 
proof of the existence of snow deposit. He points out 



• I use the terms "east" and " west" throughout this paper, 
from our point of view. An inhabitant of the moon would, of 
course, regard the slopes facing the sunset as the western slopes. 



April, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



^1 



that though the central regions of the disc are as " rough 
and mountainous as that near the pole " they are very much 
darker. It is hardly the fact that the equatorial regions 
are as rugged as those of the North Pole, hut when we 
compare the equatorial regions with the polar under the 
same conditions of foreshortening as well as of illumination 
the latter have no evident superiority in brightness. It 
is abundantly clear why the regions near the edge of the 
disc, whether polar or equatorial, appear the brightest, 
for it is just here that the darker valleys are concealed 
from us and that the steep mountain slopes are presented 
to the fullest advantage. 

The question as to whether there are anywhere upon 
.the moon deposits of snow is too large a one to be settled 
by an appeal to the evidence which even so grand and 
extensive a formation as the Apennines and their high- 
lands can afTord, but so far as they are concerned the 
verdict would clearly seem to be in the negative. It must 
always be difficult to distinguish upon the moon betw^een 
changes which are simply due to changed illumination, 
and therefore which are apparent only, and changes 
which are real but are strictly seasonal, for the period of 
both will be the same. But in this particular region both 
theory and observation seem to unite in discountenancing 
the idea of snowfall and in ascribing the apparent changes 
in the brightness of the Apennine highlands purely to 
the varying incidence of light on surfaces of different 
reflective power. 

The CaLrvQLls of Ma^rs. 



By \V. F. Denning, F.R.A.S. 

Recent observations and discussions in reference to the 
canals of Mars have been very important and will be 
the means of clearing up doubtful points and putting our 
knowledge of the planet's surface configuration on a well- 
assured basis. The fact that many of the spots on I\Iars 
represent real features give them a special interest, for the 
other large planets of our system appear to be too densely 
involved in atmospheres to exhibit the material conforma- 
tion of their globes. 

Schiaparelli discovered the canaliform aspect of ;\lars 
in 1877, and the general correctness of the Italian astro- 
nomer's work has been affirmed by many of the leading 
planetary observers in subsequent years. But the path 
of the pioneer is difficult and apt to carry one a little 
astray through its general direction may be accurate 
enough, Schiaparelli has not been successfully followed 
in all the details included in his charts of Martian topo- 
graphy, nor has the doubling of many of the canals been 
corroborated. But apart from the latter peculiarity his 
delineations form the best working basis for present 
observers, and carry us tar beyond the charts of Green, 
whose well-executed drawings are marred by the fact 
that he was over-scrupulous as to the insertion of details 
not prominently distinguishable. 

Schiaparelli has no doubt delineated the canals undei 
aspects too straight, hard, and uniform. P'or the most 
part the telescope displays them as really faint pencil- 
like streaks or veins, knotted with darker regions and 
by no means of equable width or even tone. Though 
classed under one name and drawn in a uniform way 
they certainly represent very dissimilar objects. 

Some of the canals are due to contrast, and r- 
apply to the boundaries between dusky areas toned a 
little more deeply than the outlying parts of tlie ruddy 
surface. 

Others are pretty consistent with their title, being 



formed of streaks apparently connectin , i%nown 

spots, and sometimes meandering over extensive tracks 
of the surface. 

Others again are composed of small irregular con- 
densations, lying approximately in rows and roughly 
blended together under the aspect of bands in which 
much detail may be momentarily glimpsed. With ordi- 
nary telescopic power, however, tlieir general appearance 
on the small disc is that of streaks or canals, and tiie 
observer (igures them as such, being unable to satisfac- 
torily define their structure in detail. 

In Marcii, 1903, I i)egan a series of careful observa- 
tions of Mars with a lo-inch reflector. I'avourahle 
weather during tlie ensuing two months enabled me to 
examine the planet on 26 nights, when 36 drawings were 
made. On the first few nights 1 detected some of the 
canals under absolutely certain characters. .\ consider- 
able number of those shown in Schiaparelli's charts were 
identified, and the result of my scrutiny was to prove the 
general correctness of his drawings. Hut I utterly failed 
to recognize the supposed double canals. To my eye, 
the lines were invariably single under the highest powers 
I could effectively apply, and I am bound to conclude 
that the gemination is not a real feature. 




Mars in the Spring of 1003. LonifUude, 2O5 . 
io°inch Kefltctor. Powers, 312 and 375. 

During my observations several striking changes were 
remarked in prominent objects, and these were probably 
occasioned l)y atmospheric movements on tl^e surface of the 
planet. The presence of clouds or obscuring vapours 
must, however, havealTected relatively small regions, for the 
markings were usually visible from night to night under 
similar aspects, allowance being made for the variable 
definition. 

The white spots formed striking features, and especially 
so when on or near the edge of the disc. They appeared 
to be equally as permanent as the dark markings. 

From observed transits of the Syrtis Major, compared 
vith some I obtained with a 4y-in. refractor in February, 
. ^69, I determined the rotation period as 24h. 37m. 22-7S. 
from 12,135 rotations. 

There are really many distinctions in the canal-like 

markings ; some of them are quite broad and diffused 

hadings, while others are narrow-, delicate lines. The 



68 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 



dusky knots (called Oases by Lowell, who claims to have 
discovered them) were distinctly seen here in 1S84, 1886, 
and other years. In Natuvc for June 3, 1886, I refer to 
the canals as •' linear shadings with evident gradations in 
tone and irregularities occasioning breaks and condensa- 
tions here and there." 

The ingenious experiments conducted by Messrs. 
Maunder and Evans {Montlily Notiiis, June, 1903) e.xplain 
some of the observational results without throwing doubt 
on the whole canal-system of Mars, as some readers have 
supposed. Certain of the canals are indeed so conspi- 
cuous as to form objective features comparable in point 
of distinctness and certainty with the dark belts of [upiter 
and Saturn. 

If we could greatly enhance telescopic power and 
examine Mars under a sufficiently amplified disc, the 
canals would probably look very different to those shown 
in the miniature views supplied in ordijiary instruments. 
We should see them as large blotchy bands of dusky 
material having no resemblance whatever to sharply-cut 
waterways. The south equatorial belt of Jupiter consists 
of a series of spots, and it presents a curious transforma- 
tion under magnifying powers of 50 and 300. With the 
former it forms a \ery dark narrow streak, but with the 
latter it is broken up into masses of flocculent material 
covering an extensive track. 

If the existence of the Martian canals has been doubted, 
it is partly the fault of certain observers who ha\e greatly 
multiplied the real number of these objects, drawn them 
under unnatural aspects, and elaborated the general 
appearance of Mars in a manner palpably inconsistent 
with telescopic revelations. 

Mr. Story remarks that " it is time an end should be put 
to the inquisitorial fashion of refusing credence to scientific 
discoveries." It is true that certain forms of criticism 
merely harass and embarrass observers, without effecting 
any useful purpose. On the other hand, we cannot unre- 
servedly accept everything offered us in the way of 
observation, real and \isionary, objective and subjecti\e. 
Astronomical history would form a curious medley of 
fact and fiction (chietiy the latter) if all the supposed 
" disco\eries" of past years were credited and reiterated. 
Criticism has occasionally proved a wholesome and 
necessary corrective to results of abnormal and unsup- 
ported character. 

Conflicting testimony in planetary observation is usually 
attributed to the differences in telescopes, eyesight, and 
local atmospheric conditions. But the more potent cause 
is to be traced to the observers themseKes, who differ 
widely in their discretion, judgment, and interpretations. 
One man will accept and possibly elaborate extremely 
delicate features very imperfectly and uncertainly glim psed. 
Another will absolutely reject similar appearances. Two 
things conae actuely into play and are directly opposed, 
viz.: (i) The dominating deaire to glimpse novelties and 
gain repute by eclipsing past records ; and (2) the 
necessity of accepting only what is certainly and steadily 
seen to the exclusion of all doubtful features. On these 
points obser\ ers differ vastly ; some of them do not 
sufficiently realise their responsible positions, and hurriedly 
make records not justified by telescopic evidence; others 
are perhaps too punctilious and apt to reject details which 
are real, though only faintly and fitfully glimpsed. 

In judging the quality of results it should be remem- 
bered, as a most important factor, that the individual 
characteristics of the observer play a very prominent 
part. Some people possess the faculty of seeing objects 
double. (Jthers will invariably discern novelties where 
none are visible. Others, again, will detect canals as a 
necessary feature of a planetary disc. Thus Mercury and 



Venus have been supposed to display these markings very 
conspicuously. Phenomenal vision will not explain the 
anomalies alluded to. Objective markings are capable of 
being corroborated without any difficulty. The spots on 
Saturn were distinguished by many observers shortly 
after their discovery. There is no reason why canals 
should prominently diversify IMercury and \'enus as seen 
by one observer, while as viewed by others the discs of 
those planets appear, under the best circumstances, abso- 
lutely free from such markings. On many occasions during 
the last few years the beautifully defined disc of Venus 
has been examined by the writer, but not the v^estige of 
a canal has ever revealed itself; yet at the Lowell Obser- 
vatory, Mexico, " the markings are perfectly distinct and 
unmistakable, invariably visible, and nothing but a very 
unsteady air can obliterate them " [Montlily Notices, 
Vol. L\TI. 1896-7, pp. 149 and 402). 

Flammarion was probably quite correct in his expres- 
sion (" Knowledge," November, 1897) that " the maps 
of Venus made up to the present time are illusions." 

But our present concern is with l\Iars. The story of 
his canal-like markings is a true one, though it has been 
occasionally exaggerated, and it will survive all the oppo- 
sition levelled against it by sceptics and incapable ob- 
servers. The northern hemisphere of the planet seems 
replete with dusky streaks forming the canals. They 
may not indicate water courses, and their real aspect may 
be something very dissimilar to that displayed in ordinary 
telescopes, but with the means employed observers are 
correct in representing many of them as lines and bands 
of shading connecting the more bulky spots. 

The Spinthariscope. 

The ingenious mstrument to which Sir William Crookes 
gave the name of the Spinthariscope, and which he de- 
vised to show the torrent of rays or the fragments of 
atoms which are continually being shot out from radium, 
is now a familiar object to most scientific people. The 
instrument as is well known consists of a little screen of 
zinc sulphide or blende, at a slight distance from which 
a fragment of radium bromide is situated on a pointer. 
,\s the emanations from the radium strike the screen 
they produce an effect similar to that which a bullet pro- 
duces when it strikes a target, and by means of a magni- 
fying glass the phenomenon is rendered clearly visible. 
The instrument is now made by Messrs. A. C. Cossor, 
and one of them which has been sent to us shows the 
scintillation with remarkable clearness and \i\idness. 
It is, perhaps, the most ingenious, and certainly 
the most lasting, scientific toy that ever has been 
produced. 

Some time a^o, in a lecture to the Camera Club, Mr. Duncan 
deitroyed the poetic belief, relating to the nautilus, which is 
expressed in Popes lines: 

" Learn of the little nautilus to sail, 

Spread tliine oar and catch the driving gale " — 
bv remarking that the little sails which the nautilus was popularly 
and poetically supposed to spread were, in fact, never raised at all, 
but were always tightly clasped about the shell. In a paper con- 
tributed to the Xatuittl History Miigit::inc. Captain Barrett Hamilton 
disturbs an idea relating to the wings of the flying fish that is at 
least ecjually widespread. In the true frying fish Captain Hamilton 
says the " wings " are never moved as organs of flight. They may 
vibrate or quiver under the action of air currents, or a shifting a 
little of their inclination by the fish, but the whole motive power 
is supplied by the powerful tail. The wings are a parachute to 
augment the action of this propeller. Their motions are in no way 
comparable to those of the v.ings of a bird. 



April, 1904.] 



KNOWLEDGE cS: SCIEXTIEIC NEWS. 



69 



The Face of the Sky for 
April. 

By W. SiiACKLETON, F.K.A.S. 



The Si'N. — On the ist the Sun rises at 5.3S, and sets 
at 6.31 ; on the joth he rises at 4.37, and sets at 7. ly. 

The equation of time is negligible on the 15th and 
i6th, hence these are convenient days for the adjiistniont 
of sun dials or for laying down a meridian line to a close 
approximation. 

SunsjXits are of frequent occurrence ; their positions 
may be located by the use of the following table : — 



Date. 


Axis inclined to W. from 
N. point. 


Centre of disc, S of 
Sun's equator. 


\pril 5 •• 
.. 15 •• 
.. 25 .. 


26" 29' 
20° 14' 
25" 14' 


6° 111 
5° 27' 
4° 34' 



The Moon : — 



Date. 



Phases. 



April 7 . . 
.. 15 •• 
.. 23 .. 
., 29 .. 



(T Last Quarter 

• New Sloon 

]) First Quarter 

O Full Moon 



H. M. 



5 .53 P-m- 

9 53P-m 

4 55 a.m. 

10 36 p.m. 




Occulta.tions. 

The following are the principal occultations visible at 
Greenwich at convenient times : — 



Saturn is a morning star, rising at 3.15 a.m. near the 
middle of the month ; he is situated in Capricormis, and 
conseciuently low down in the sky. 

I'ranus rises on the isl alunit 1.30 a.m., ami on the 
30th at 11.30 p.m.; througlioul llie month the pi. met is 
close to 4 Sagitlarii, Ix-iiig only si.\ minutes wt-st anil 
having approximately the same declination as the star. 

Neptune is getting more to the west, and sets about 
.S.30 p.m. near the middle of the month. He is describ- 
mg a retrograde path towards >; Geminorum ; his posi- 
tion with respect to that star may be seen on reference to 
the chart given in the January number. 

IMeteor SiiowiiKs : — ■ 







Radiant. 


Character- 
istics. 


Dale. 


R.A. 


Dec. 


Name. 




h. m. 








Apr.ij-May i 


16 


+ 47° 


T IlFrculids 


Small , short 


,, 20-2I 


17 20 


4- 30'^ 


TT 1 lerculids 


Swift; 111. white 


,, 20-2J 


IS ., 


+ ii' 


Lyrid Shower Swifi 


.. 30 


icj 24 


+ 59" 


Oraconids 


liather slow. 



The Sr.\RS. — About the middle of the month at 9 p.m. 
thepositionsof the principal constellations are as follows: 
Zenith . Ursa Majur. 
North . I'nlaiis : to the right, Ursa Minor and 

Draco; to the left, Cassinpeire and I'crseus ; 

below, Cepheus and Cygnus. 
South . Leo and Hydra; to the south-east, \'irgo; 

to the south-west, (leniini (high up), Procynn, and 

Siriiis (setting). 
West . Taurus, Pleiades, and Orion, all rather 

low down. 
East . Antiinis, Corona, and Hercules; to the 

north-east, Vi-ga rising. 
Minima of Algol may be observed on the 7th at 
10.38 p.m., loth at 7.27 p.m., and 30th at y.io p.m. 



Date 



April 2 


„ 4 
,,28 


,,29 



Star's 
Name. 



49 Librae . . 
B.A.C. 339« 
m Virginis . . 
B..\.C 4S2S 



Magni- 
tude. 



5-6 
5-9 
53 
6-0 



iJisappcarance. 



Mean Time. 



II. 4 p.m. 

925 pm- 

10.6 p m. 

9 40 p.m. 



Angle from 
N- point 



94 
118^ 



Reappearance. 



103- 
75' 



Mean Time. 



12.9 a.m. 
10.33 p.m. 
11.18 p.m. 
10.37 p.m. 



Angle from 
N. point. 



Moon's 
Age. 



297 
284° 

303" 
327° 



d. h. 

17 17 

9 o 

13 o 

14 o 



The Planets. — Mercury should be looked for in the 
N.W. shortly after Sunset from the 15th to the end of the 
month. .Vbout this time the planet is in the most favour- 
able position for observation for the present year, and sets 
about two hours after the sun. On the 21st he arrives at 
greatest easterly elongation of 20 1 1', and although this 
is not so large as the autumnal elongation, the greater 
inclination of the ecliptic to the horizon at this time puts 
the planet into a much more favourable position tor 
observation. 

The diatneter of the disc is 8"-o. 

\'enus cannot readily be observed, as she only rises 
about half an hour in advance of the Sun, and is thus 
lost in the bright dawn. 

Mars is practically unobservable, as he sets before it 
is really dark. 

Jupiter was in conjunction with the Sun towards the 
end of last month, and is therefore too close to the Sun 
for observation. 



Tei.i;sc()Mc Oi3Jec'is: — 

Double Stars:—-, N'irginis, Xll.'' 37"% S. o'-' 54', mags. 
3, 3 ; separation 5"'7. Hinary system ; both components 
are yellow, though one is of a deeper hue than the other. 



3-m. 



An eyepiece of a power of 30 or 40 is reijuired 
to effect separation. 

rr Bootis, XIV.'' 36™, N. 16^ 53', mags. 4, 6; separa- 
tion 6". K'equires a power of about 40. 

I Boc/tis, XIW' 41"', N. 27° 30 , mags. 3, 6i; separa- 
tion 2"-7. Very pretty double, with good colour contrast, 
the brighter comiwjnent being yellow, the other blue green. 

;. Bootis, XI\'.'' 47™, N. 19' 31 , mags. 5, 7; separa- 
tion, 2"'4. Binary ; one component being orange, the 
other purple. 

Clusters :— M 3 {Canes Vauitici). XUl.'' 38"% N. 28 48'. 
This object, though really a globular cluster of myriads 
of small stars, appears more like a nebula in small tele- 
scopes. It is situated between Cor Carnii and Anturus, 
but rather nearer the latter. 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 




ASTRONOMICAL. 

M. Ja.nsserv's Photogra.pKic Atla^s of 
the Sun. 

Some twenty-eight years ag(i, M. Jansscn set on foot a 
photographic study of the solar surface at the Meudon Obser- 
vatory, of a somewhat special kind. His object was to obtain 
the greatest possible sharpness of definition, and for this pur- 
pose he had an objective constructed for him by I'razmowsUi 
which brought the rays near the G line of the Fraunhofer 
spectrum, and practically these alone, to a well-defined focus. 
In conjunction with this instrument he used collodion plates, 
sensitised by bromo-iodide, in which the iodide predominated, 
with a small range of sensitiveness which corresponded to the 
region of the spectrum for which the object glass had been 
constructed. The photographs were therefore obtained 
almost by monochromatic light, and were exceedingly' sharp. 
The objective employed had an aperture of 0-135 metres and 
focal length of 2 metres, a secondary magnifier enlarging the 
image of the sun in the telescope some 15 diameters. Some 
of the most characteristic and best defined from the store of 
over 5ooo negatives which have now been accumulated at the 
Meudon Observatory have been reproduced, enlarged four 
times from the originals, in a superb atlas, recently published 
by M. Janssen. These plates, 30 in number, and 21 inches by 
i<S in size, are on a scale of about 4 feet to the solar diameter, 
and show the intimate structure of the solar surface with a 
minuteness and detail never seen in any previous publication; 
the minute granulation of the surface and the dift'ercnt forms of 
the reseau photospherique being most admiralily illustrated. 



Some Peculiarities of Comets* Tails. 

In an article in " Popular Astronomy," illustrated by a 
number of beautiful photographs. Professor Barnard draws 
attention to some peculiarities apparent in the photographs 
of some recent comets which do not seem to be sufficiently ex- 
plained by the well-known theory of Professor Bredikhine of 
the repulsive action ex-ercised by the sun upon the cometary 
nucleus. The comets specially remarked upon are those of 
Swift, 1902 : Brooks, 1893 ; and liorrelly, 1903. The remark- 
able way in Avhich the tail of Brooks' Comet was contorted and 
broken on October 22, 1893, seems to clearly indicate that it 
had encountered some resisting or disturbing medium. The 
case of Borrclly's Comet was not less remarkable, but of a 
diflerent kind. Here a tail, itself apparently uninjured, was 
sec'U at a distance from the head. In this case there seems to 
have been a slight but sudden change in the direction of the 
emission of matter from the comet's head, thus cutting off the 
supply from the first formed tail. The detached tail, however, 
showed no clear evidence of acceleration in its motion, and 
this would suggest that the sun had little to do with its flight 
into space. 

Radial Velocities of Twenty StaLrs of the 
Orion Type. 

Amongst the Decennial Publications of the University of 
Chicago IS a Memoir by Messrs. Edwin B. P'rost and Walter 
S. .-Vdams upon the motions in the line of sight of twenty stars 
of the Orion type. The photograjihs of these spectra were 
obtained with the Bruce spectrograph attached to the great 
refractor of the Yerkes Observatory. I'he comparison spectrum 
was always that of titanium, and sometimes, in addition, iron 
or chromium, or else a helium tube wliich also gave the 
hydrogen lines. The absolute velocities of the twenty stars 
observed was evidently very small, and when corrected for the 



solar motion gave 7 kiloiuitri-- a second as the mean of the 
twenty radial velocities. The proper motions of these twenty 
stars (not their i-lciI radial velocities, as Professor Frost's 
memoir has been curiously niisreadi are exceedingly small ; 
the mean for nineteen of them only being o"oi5 on a great 
circle, which is much smaller than for solar stars of corre- 
sponding brightness, and indicates that the Orion type stars 
are, as a class, very remote. A classification of thirty-one 
stars of the type is given at the end of the paper, according to 
the character of the lines of helium, silicon, nitrogen, and 
o.xygen in their spectra. 



The Starrs of Secchi's Fourth Type. 

Another of the Decennial Publications is a Memoir by Pro- 
fessor Haleand Messrs. EUerman and Parkhurst onthe spectra 
of stars of the type of 152 Schjellerup, the Fourth Type of 
Secchi's classification. The spectra of eight stars were 
examined, and some most important conclusions reached. A 
great number of bright and dark lines were detected over and 
above the violet flutings of cyanogen, and the flutings of the 
Swan spectrum. Of the dark lines, a large number were 
measured, showing the presence of carbon, hydrogen, mag- 
nesium, sodium, iron, calcium, and other metals recognised m 
the sun. The carbon and metallic vapours appear to be very 
dense, and to lie immediately aliove the photosphere ; above 
these dense vapours are others giving rise to the bright lines, 
of which about 200 are present. None of these could be 
identified with certainty, but a few may possibly correspond 
to the bright lines of the W'olf-Rayet stars, which the Fourth 
Type spectra resemble in some other characteristics. Many 
lines widened in sunspots are represented by strong dark lines, 
suggesting that these stars may be largely co\ered by spots 
akin to those of our sun. Some twenty per cent, of the Type 
appear to be variable, exceeding the proportion observed in 
the case ofThird Type stars. Professor Hale suggests that the 
Third and Fourth types should be classed together as pro- 
bably having developed from stars like the sun through loss of 
heat by radiation. 



ZOOLOGICAL. 



The Colours of Lobsters and Prawns. 

ExPKKiMENTb uiidert.ikeii many years ago were belie\ ed to 
demonstrate that the colouring of Crustacea was largely, if not 
entirely, of a protective nature. F"or instance, when prawns 
or young lobsters were placed, in broad daylight, on black 
dishes, the pigment-bearmg bodies, or " chromatophores," 
in their integument were observed to expand, with ihe result 
that a dark type of coloration in harmony with the tone of 
the surroundings was produced. Conversely, when the 
creatures were placed on a white dish, the pigment bodies 
contracted, with the resulting production of a pale tone of 
coloration, harmonising so tar as possible with the back- 
ground. Moreover, if the crustaceans were deprived of sight, 
no such adjustment of colouring occurred, although it took 
place immediatelv that vision was restored. 

From these and other experiments, it has become the cur- 
rent opinion that the pigments of crustaceans are superficial 
and sporadic in distribution, that they are confined to single 
cells— chromatophores — of the epidermal or connective 
tissues, and that they are either protective in function or form 
a waste functionless product of development. 

Recently, the subject has been taken up anew by Messrs. 
Keeble and Gamble, the results of whose investigations 
appear in the Philosophical Tnuisiutiuiis of the Royal Society. 
While fully recognising the paramount influence of background 
on the colours of crustaceans, the authors find themselves 
compelled to adopt an attitude of reserve and indecision in 
regard to most ol the foregoing points. They state, for in- 
stance, that even the protective function of colour is not 
definitely determined by experiment : while pigment in crus- 
taceans may be deep-seated, and may also occur in complex 
organs not 'functionally related to one another, l-'urther in- 
vestigation is necessary before anything definite can be 
predicated as to colour-function in these creatures. 



April, 1904.] 



KNOWLEDGE .^v SCIENTIFIC NEWS. 



71 



Arv English Spiral-Sawed Shark. 

For many vears certain remarkable bodies, somewhat resem- 
blins a large watch-sprinj; armed on the convex side with teeth, 
have been known from the Carboniferous and Permian rocks ol 
various countries ; the most nearly complete coming from 
Russia. There has, however, been much uncertainty as to 
their true nature. At first they were supposed to be the fin- 
spines of fishes ; but the aforesaid Russian specimens clearly 
showed that they belong to the front of the jaws of sharks, and 
that they are true teeth, which are mounted upon their sup- 
porting base in such a manner as to form a spiral. Hence the 
name of spiral-sawed sharks for the group to wliich they per- 
tained. Hitherto this group has been known only from North 
America, .Australia, Japan, and Russia; the type genus being 
Edesttis. Recently, however, Mr. E.T. Newton, in the Qiuirhi-ly 
Journal of the Gcohi^ical Society, has described part of the 
" saw " of one of these remarkable sharks from a marine band 
in the Coal Measures of Nettlebank, North Staffordshire. 
giving the name of Edcstus triscrraliis to the species it 
represents. 

The Medusa of Lake Tanganyika. 

The discovery of the Freshwater Nfedusa, Limiioclida Tan- 
giinyiku, in Lake Victoria, which was announced to the Zoo- 
logical Society of London at their meeting in December last 
by Professor Rav Lankester, is an event of some scientific 
importance, as this remarkable form had been previously be- 
lieved to be entirely restricted to Lake Tanganyika, and to be 
one of the most significant pieces of evidence in favour of Mr. 
Moore's theory of Lake Tanganyika having been formerly 
connected with the ocean. When Professor Lankester 
exhibited his specimens he was not quite certain that they 
had been obtained in Lake Victoria, but we believe that 
further information recently received leaves absolutely no 
doubt on this point, the specimens having been tak(Mi in Kavi- 
rondo Bay by Mr. Hoble\-. Moreover, confirmation on this 
subject has been furnished by a French Naturalist, M. Ch. 
Gravier who obtained nine examples of this Medusa in the 
Bay" of Kavirondo on the i6th of September last year, as has 
been announced by M. Perrier to the French Academy of 
Sciences. ^L Perrier agrees with Professor Lankester in con- 
sidering the Medusa from Lake Victoria to lie identical with 
that of Lake Tanganyika, and of this we believe there is no 
doubt. 

Some people have thought that this remarkable discovery is 
rather a serious blow to the theory of the " halolimnic" nature 
of Lake Tanganyika, but Mr. Moore does not seem to be at all 
disconcerted by it. In a letter to Nature (of February i8th) he 
maintains that so far from this fresh piece of knowledge 
"being in any way antagonistic to the view in question," the 
existence of the Medusa in other Lakes is "exactly what one 
would anticipate, supposing the halolimnic theory to be 
correct." Mr. Moore thinks that it may be explained in 
two ways. It is quite possible, he believes, that the Medusa 
may be a recent importation into Lake Victoria from Lake 
Tanganyika, caused by the opening of new trade-routes 
between the Lakes, and the carriage of water in gourds and 
other vessels from one lake to another. If this shall be found 
not to have been the case, then future researches will probably 
result in the discovery of the rest of the " halolinmic fauna," 
or part of it, in Lake Victoria. This, it is maintained by Mr. 
Moore, would confirm the view that he has already put for- 
ward, " that the ancient sea from which the halolinmic relics 
sprang spread nmch further towards the east than was at first 
supposed." 

To settle this and many other interesting problems it is 
certainly advisable that a much more accurate investigation of 
the Fauna and Flora of Lake Victoria should be made than 
has yet taken place. Lake Tanganyika seems to have more 
attention paid to it as yet than Lake Victoria. 

The Palolo Worm. 

In a recent issue of our contemporary, the A meruan 
Naturalist, Mr. W. McM. Woodworth gives an interesting 
account of the palolo worm of Samoa and Fiji. For more 
than half a century the appearance of swarms of these worms, 
apparently always just before the full moon, in October and 
November, has been familiar, and it has also been known that 



the worms forming those swarms are always imperfect. It is 
now ascertained tliat these palolo arc the slender posterior 
generative portion of the annelid known as liiiiiiic viriilis, 
which at the swarming season becomes detached and free- 
swiunning. This portion is very much longer tlian the proper 
body of the creature, which is, however, much stouter. The 
complete worm dwells in coral-reefs, into which it burrows ; 
and, curiously enough, its existence there was quite unknown 
to the Samoans, to whom the demonstration of its presence by 
Mr. Woodworth came as a revelation. The worm only attains 
its full dimensions shortly before the swarmint^ season. 



A Precious Product. 

According to a writer in the February number of tlie 
/Zoologist, a lump of ambergris, weighing about 4! lbs., w.is 
taken from tlu' intestines of a male sperm-whale killed last 
June between Iceland and Norway, in about tlie latitude of 
Trondhjem ; a very unusual resort, by the way, for cetaceans 
of this species. Ambergris, which is very largely used in pcr- 
fumerv, is solelv a product ofthe sperm-whale, and appears to 
be a kind of biliary calculus. It generally contains a number 
of the hornv beaks of the cuttlefishes and squids, upon which 
these whales chiefly feed. Its market price is subject to con- 
siderable variation^ but from £3 to £4 per ounce is tlie usual 
average for samples of good quality. Mr. T. Southwell, the 
writer referred to, states, on the authority of a correspondent 
in the sperm-oil trade, that in 1898 a merchant in Mincing 
Lane was the fortunate owner of a lump of ambergris weighing 
270 lbs., which was sold in Paris for about 85s. per ounce, or 

£i^'i^''- ... ,, . 

African Insects. 

Descriptions and illustrations of the entomological f.iuna of 
Tropical -Africa are in course of publication in the Annaks of 
the Congo Museum, issued at Brussels. In one of the two 
latest parts, Mr. K. Lameere describes the longicorn beetles of 
the sub-family Prionina:, while in the other Mr. H. Schouteden 
writes on certain groups of flower-bugs. Both meiiioirs are 
illustrated by coloured plates remarkable for their beauty of 
execution. 

Papers Read. 

At a recent meeting of the Royal Society a communication 
was read on the pharmacology of Indian cobra-venom, based 
on experiments made by Captain R. H. Elliot, of the Indian 
Medical Service. On the 3rd of March, at the Linnean Society, 
Dr. J. G. de Man described certain species of the crustacean 
genus Piild:inoii from Tahiti, Shanghai, New Guinea, and West 
.Africa. The papers read at the meeting of the Zoological 
Society, held on March ist, included one by Mr. K. T. Leiper 
on A vagina incola, a new genus and species of the Proporiiia-, 
with a note on the classification of the group ; and a .second, 
by Dr. Einar Lijunberg, of Stockholm, on two specimens of 
hybrid grouse of which the exact parentage is known. The 
papers read at the meeting of the same Society on March 15 
comprised one by Mr. F. E. Beddard on the anatomy of li/ards, 
one by Mr. Lydekker on certain points in connection with the 
skull and colouring of the extinct quagga ; a second by the 
same author on the distinctive features of the Asiatic wild asses, 
respectively known as the Chigetai and the Kiang ; one by 
Mr. R. J. Pocock on a new African monkey, and one by Mr. 
P. J. Lathy on additions to the list of Dominican buttertlies 
{Rh op aloe era). 

Certain interesting specimens were exhibited at the Zoolo- 
gical Society's meeting on March i. In the first place. Dr. 
(ilinther directed attention to hybrids between Reeves's 
pheasant and the silver pheasant. Next, Mr. Thomas exhi- 
bited the skull of a large buffalo killed by Colonel Delnie- 
Radcliffe in S.W. Uganda, which was believed to indicate a 
distinct local race of Bos caffer. The same gentleman also 
displayed a new species of fruit-bat from P'ernando Po, 
remarkable for its small bodily size. Thirdly, Mr. J. G. 
Millard exhibited a collection of skins in illustration of the 
life-history of the grey seal, whose geographical distrilnition 
was discussed. A few other minor exhibits were likewise 
made. 



72 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 



Corrigenda. 

Owiiif,' to an unfortunate oversight, the author of the article 
on the Ancestry of the Camel and writer of Zoological Notes 
in the March Number had no opportunity of revising the 
proofs ; the followin.t; corrections are therefore necessary. 
P. 25, ist Col., line 17 from bottom, for ga:elhi rtMil f;ii:c!le. 

,t ,, 2iid ,, ,, 20 ,, top ,, are ,, is. 

.. ^fi. .. .. .. 10 ,. ,, ,, Li)ita ,, Uinta. 



27. 'St . 


., 26 


, ,, 


., Procamelas 


Prociiinelus. 




4 . 


. bottom 


,, Pliancheniu 


, Pliauchenia. 


.. 2nd , 


., I'J 


> >i 


,, Camelas , 


, Cavielus. 


28, I St . 


,. 28 , 


top 


,, Aliicamclas 


, Alticavielus. 




.. 25 . 


1 .. 


,, Procamelas 


, Procamelus. 




s , 


, bottom 


,. Paracamelas 


, Paracamchis. 


4-', .. 


.. 33 , 


, top 


., La da 


, La do. 


.. 2nd , 


ist line 




.. A'»/0 


, Giilo 


.. ., 


line 35 . 


bottom 


, Maiayensis 


, Malayenses. 


.> .. 


.. 24 , 




, Parachivomys , 


Metachiromys 


,. ,. 


12 , 




, Soemmeringi 


SLcmnierringi. 



BOTANICAL. 



The rare occurrence ofstamens developing inside the ovary has 
been recently met with in a Caryophyllaceousplant, Mclandi-yum 
ruhnim, and is made the subject of a paper by Professor F. 
Bucbenau in the Bericlitc lier DeutscJitu Butuiiisclieii Gesdhcluift. 
XXI. The material was collected in the neighbourhood of 
Marburg, Germany, having tirst attracted attention on account 
of the absence of petals. A closer examination revealed great 
irregularity in the structure of the ovary and in the number of 
the stigmas, and on making a section of the former it was 
found to contain six to nine, sometimes ten, well-developed 
stamens arising from its base, the central placenta, with the 
ovules, being altogether wanting. Dr. M. T. Masters, in his 
V'fgvtiilih- Teraioloi^y, refers to a Myrtaceous plant, Dicckca 
itiosmicfoliii. in which a similar abnormality was found. The 
ovary contained no ovules, but numerous stamens, in various 
stages of development, were attached to the inside walls. In 
other respects the flower appeared to be quite normal. 

The standard work on the flora of South Africa is, of course, 
the Flora Ciipciisi.-i. which was begun bv Harvey and Sonder, 
and is being continued under the editorship of Sir \V. T. 
Thiselton-Dyer. This work, of which anew part hasjust been 
issued, gives full descriptions, with synonomy and localities, of 
all the known flowering plants of Africa south of the tropics, 
and is necessarily bulky and expensive. Professor Henslow's 
South Afruaii Fluu-crini; Plants, lately published by Longmans, 
Green, and Co., will be welcomed by those who seek a handy 
inexpensive work on the South African flora, but who do not 
require the fulness of the Flora Capi-nsis. 

The very imperfectly known flora of Siam is being investi- 
gated by Mr. F. N. Williams, who has commenced an enumera- 
tion of the plants of this country in the last number of the 
Bulletin lie VHcrhkr Boissier. His work is based on the material 
in the Kew Herbarium. Collectors have paid very scanty 
attention to this flora, and several sets of plants, said to be 
from Siam, are shown to be from localities outside its boun- 
daries, and cannot, therefore, be included in his enumeration. 
Some preliminary remarks on the flora were made by the 
same author in the Journal of Botany of September, 1903, 
where he mentiors the interesting fact that the well-known 
commercial product, Siam benzoin, is obtained not from Siam 
but from a locality in the Lao province of French Indo-China' 

PHYSICAL. 



Chlorophacne. 

Chlorophane is the name given to those varieties of Fluorite 
(Fluorspar Calcium Fluoride), which possess to a noticeable 
extent the property of " thermo-luminositv," that is to say, 
of spontaneously emitting light when heated. The tempera- 
ture at which this phenomenon takes place is not the same in 
all cases, but varies with different varieties of the mineral — 
the heat required being generally between 300 and 400' C. 
On first heating little or no light is emitted, until what mav be 
called the " critical temperature " is reached, when the Chloro- 
phane glows brightly and continues to glow for some hours 



after cooling to ordinary temperature, but more feebly. The 
colour of the light varies, blue and green predominating. 
Hagenbach found that the spectrum of phosphorescent Fluorite 
consisted of onl}^ nine bands, four blue, two green, two yellow, 
and one orange. .As the relative intensity of these bands is 
continually changing, it is easy to understand the different 
colours pre,sented by different varieties of this mineral. The 
pure white Fluorite does not possess the properties of Chloro- 
phane, apparently the presence of some other salt or impurity 
is necessary, as in the case of phosphorescent Calcium Sul- 
phide. 

* * * 

ChlorophaLne a.rvd P.adium. 

Madame Curie states [Chanual .V.ai, \'ol. L.X.X.WUL, 
No. 2293, p. 223), that: "Fluorite when heated undergoes a 
change, which is accompanied by the emission of light. 
If the Fluorite is afterwards subjected to the action of 
Kadium an inverse charjge occiu's. which is also accom- 
panied by an emission of light." This being so, what 
effect would be produced by first acting upon the Fluorite 
with Kadium, and then applying heat ? The following 
experiment was devised for the purpose of ascertaining 
this. A small crystal of Chlorophane was exposed for six hours 
at a distance of two millimetres from 10 milligrams of Kadium 
Nitrate (Giesel's preparation) in such a manner that only the 
(3 and 7 rays acted upon it. The initial fluorescence excited 
under these conditions was fairly bright, and persisted after 
removal but slightly diminished in intensity, and when kept 
at uniform temperature fell to half value in two to three days, 
dying down to negligible quantity in six to seven days. The 
changes in thermoluminosity were very marked, a very slight 
rise in temperature, such as that produced by placing the 
crystal in the palm of the hand, sufficing to increase the 
luminosity about 100 percent. This increase is at the expense 
of the duration of retained fluorescence. The "Alpha" rays 
of Kadium are without appreciable effect on Fluorite. Careful 
observations made with a Bismuth plate covered with a 
deposit of Markwald's Kadio-tellurium (Polonium ?) of sufficient 
radio-activity to cause a piece of Willemite to glow brightly 
when in close contact, gave only negative results. It would 
be of great interest to know the exact nature of the change 
occurring in the chlorophane, whether it is of a chemical or 
physical kind. — Ernest L. Arnibrecht, M.P.S. 

[N.B. — The writer also finds that the above properties are 
not confined to Chlorophane, but are also shown by Kunzite, 
with which very pretty experiments may be made on above 
lines.] 

Wireless Telegraphy Experiments between 
Germany and S\veden. 

The Berlin Gesellschaft fiir Drahtlose Telegraphic some 
time ago installed two wireless telegraphy stations on the 
Norwegian Loffoden Islands, the two points chosen being 
50 km. distant and separated by high continuous rocky masses, 
so as to oppose serious obstacles to the passage of the electric 
wave. These stations were designed for dry cell operation, in 
order to ascertain whether communication over distances as 
high as 50 km. would be possible with such small amounts of 
electric energy. This, however, was found not to be the case 
as the primary energy of a limited number of dry cells proved 
insufficient, a cpnsumption of about 200 watts being necessary 
to overcome the obstacles on the passage of the electric waves. 

The experiments between Germany and Sweden, as con- 
templated for some time past, were begun on December i6th, 
when wireless telegraphy communication was secured between 
Oberschiinweide, near Berlin, and Karlskrona, a Swedish naval 
station, over a distance as high as 450 km. The results so 
far obtained are said to be quite satisfactory. 

The " Telefunken " system used is a combination of the 
Braim and Slaby-Arco schemes which, we learn, is being fre- 
quently used with the Swedish Navy. 



The Nationa.! Physical La.boratory. 

One of the prominent even tsof the past month w.is the annual 
visitation and inspection of the important standardizing and 
testing laboratory at Bushey House, Teddington. Erstwhile 
a Koj'al domicile, the mansion and adjacent buildings are now 



April, 1904.] 



KNOWLEDGE c^- SCIENTIFIC NEWS. 



73 



devoted to experimental work di'siL;iu ,, , note the joint 
interests of the nation's manufacturing industries (in the con- 
duct of which appUed knowledse is requisite) and theoretical 
inquiry of a scientific character. Probably few of the .general 
public who visit Bushey Park in such numbers are aware of 
the proximity of the National Physical Laboratory, still less 
of its. aims, .although it is a public institution maintained by means 
of the taxpayers" money. Here, however, a great work is unob- 
trusively going forward.whose benefits spread themselves far .and 
wide. Many .and varied are the investigations pursued. In 
electricity, for example, is one on the effect of temperature on 
the insulating properties of materials used "in dynamos, 
motors, and transformers; in thermometry a researcli on the 
specific heat of iron at high temperatures ; in metrology, the 
standardization of the steel yard and nickel metre; and in 
metallurgy a series of tests on nickel steel. Then, in the de- 
partment of engineering, experts say that the inquiries in 
hand are eminently useful to a producing country such as 
England is, and hopes to remain, despite her foreign competi- 
tion. Comprised in electrotechnics are tests on electrical 
instruments, ammeters, wattmeters, voltmeters, and other in- 
dispensable adjuncts to the needs of industry, .\gain. in 
chemistry, optics, and photometry, the record of investigation 
bears the same tendency. 

The laboratory is, of course, a young organisation as yet ; 
but its operations are ramifying in all directions under the 
able giuidance of Mr. K. T. Glazebrook. F.R.S. But, as Lord 
Rayleigh, the Chairman of the General Board, pointed out the 
other day, unless adequate funds are provided to meet the 
national purposes of the foundation the institution must fail 
in accomplishment, and a starved laboratory would jirobably 
prove a worse evil than none at all. Besides, it should be 
borne in mind that Paris and Washington have recently fol- 
lowed the example of London in initiating standardising 
establishments intended to help national industries each, too, 
is subsidised in a far more liberal way than in our own case. 
The necessity for making better provision for the needs of the 
laboratory has lately engaged the earnest attention of the 
Executive Committee, and representations have been made 
to His Majesty's Treasury- on the subject. A detailed scheme 
for the future organization and development of the institution 
has been drawn up and submitted. This, if approved, will 
entail a revision of the existing Parliamentary grant-in-aid. 
but in view of the special functions of the laboratorv, and the 
sphere of usefulness that lies before it, strong hopes are enter- 
tained of a favourable issue to the appeal. 

COR.R.ESPONDENCE. 



A Novel Electric Traction System. 

To THE Editors ov •' Knowledge." 
Sirs, — The scheme described under the above heading in 
your March issue, taken from the Ekctrotechiiisclwr Aii^.cii^cr, 
presents such curious features that one is inclined to doubt 
whether it has been put forward seriously. To use electricill v- 
heated steam-engines in preference to electric motors would 
appear, at any rate at first sight, as an absurdity, as the 
following considerations will show. 

It may be safely assumed that the internal thermal efficiencv 
of a steam locomotive does not exceed 10 per cent., I'.t'., only 
10 per cent, of the thermal energy carried by the steam froin 
the boilers into the cylinders is converted into work on the 
piston. So that, accepting 90 per cent, as the efficiency of the 
electric heaters, and assuming the mechanical efficiency of the 
engines to be as high as go per cent., it follows that of the elec- 
trical energy supplied to the V)oiler all that is available for 
propulsive power is go per cent, of 10 per cent, of 90 per cent., 
i.e., about S per cent. Against this the ordinary electric loco- 
motive would have, as stated in the article, an over-all 
efficiency of 60 to 70 per cetit., or even more. 

Now although the actual energy for a water-power installa- 
tion in a sense costs nothing, the plant to develop it is very 
costly ; and it may be safely predicted that it would not pay 
to use a generating plant and transmission system eight or 
nine times too large to save scrapping the steam locomotives. 



This very large ratio .against the electro-thermal system 
would, it is true, be reduced by the fact that every locomotive 
would to some extent act as an eiiualiscr of the demand on the 
power-houses, reducing the excess plant that would ha\e to be 
installed ; but the larger system worked from one powerhouse, 
the less this advant.agc would becoTuc ; .ind in ;iny c.isc the 
excess of power retjuired by the electro-thermal system would 
be enormous. 

Even if under any conceivable conditions such a system 
might prove advantageous, it is certain that the figures put 
forward to justify the proposal are mitirely erroneous; and 
this confirms one's doubts as to the scheme having emanated 
from any authoritative ([uarter. 

The first point to be noted is that it is proposed to raise 
the temperature of the water from 10" to up C. recpiiring 
iHo calories per kg.; but lyo" C. is said to correspond to a 
steam pressure of 50 kg. per sq. cm. As a matter of f.ict, 
iqo° C. (= 374" F.) corresponds to satur.ited steam at about 
170 lbs. per square inch (above atmosphere), whilst 50 kg. per 
sq. cm. is equivalent to 710 lbs. per square inch. However, as 
pressure is not referred to further by the writer this discre- 
pancy does not matter much. 

But next it is said that to raise 4000 litres of water through 
180" C. will take 4000 X 180 = 720,000 calories; this is true 
if it remained water, but this amount of heat is by no means 
enough to convert the water into steam, i.e., to provide the 
so-called latent heat of evaporation. So that, whilst it might 
be correct to say that a consumption of 1000 kg. of hot water 
per hour at lyo" C. would take zz^ kilow.itts, it is very far 
from the truth to say the same of 1000 kg. of steam. 

To convert 1000 kg. of water at 10- C. into steam ;it i()o' C. 
will take, not 180, but about 635 calories per kg.; in other 
words. 635,000 calories per hour must be provided ; and if 
I calorie in the boiler requires i'275 watt-hours, the electrical 
energy will have to be supplied at the rate of 810 kilowatts, or 
more than three-and-a-h.alf times the figure given. 

.\n electric locomotive taking 810 kilowatts might be relied 
upon to give 700 to qoo effective horse-power; the electric 
steam locomotive taking the same electrical power, and evapo- 
rating steam at the rate of 1000 kg, per hour, would not give 
more than 100 to 125 effective horse-power, if so much. 
Your obedient servant, 

.A K SOLD G, Hansard. 

53. Victoria Sti'eet. Westminster, S.W'., 
March cj, 1904. 

Snake Stones. 



To THE Editors or " Knowledge." 

Sirs. — Some time ago I was much interested in a series of 
articles in the scientific column of a weekly paper on the 
subject of " Snake Stones." Nothing was said at the time in 
connection with Brazil, and as I lived in th.it country for 
several years it may be interesting to some of your readers to 
have a word on the subject. " Snake stones " are not stones 
at all. at any rate not in Brazil, and I should think they would 
be much the same all over the world. • In the articles above 
referred to there appeared to be gr*-at doubt as to what they 
are. The only ones used in the part of Brazil where I was 
were made from the horns of young deer, burnt or carbonised 
in a peculiar manner, which leaves it very suctorial, and which 
is kept as a close .secret by a very few men who make them 
for sale or barter, and try to make out that they have alu)ost 
supernatural power to heal snake bites. They are usually 
sold in pairs, and are not by any means common. In form 
they are about one inch in length, four-sidcKi, and slightly 
tapering to one end. When anyone is l>itten by a snake, one 
of these " stones " is placed on the spot and held close, while 
a band of some sort is tied tightly round the limb a little way 
back towards the trunk. The " stone " is allowed Jo remain . 
on the wound until its own weight makes it f.dl ofl, when it is' 
presumed all the poison has been extracted. It is then 
dropped into milk and allowed to soak. It is said th.it if 
the person is to get healed theiailk will turn to ,i dark bniwn. 
colour, the fact being, I suppyse.'fMat the blood held by tge . 
stone has that effect. As usual 'with these things, there are 
many superstitious beliefs in connection with these "stones," 



■^.% 



-^ 



74 



KNOWLEDGE & SCIENTIFIC NEWS. 



[April, 1904. 



and the cure is supposed to be miraculous; whereas I suppose 
that it is really due to the great capillary attractive force they 
possess, which extracts a certain amount of blood, and with it 
the poison. After being thoroughly washed out and dried 
they are ready for another occasion. Yours truly, 

James Searle. 
[Some experiments recently made in the Government Bac- 
teriological Laboratory of Natal ha\e shown that the 
mysterious curative properties ascribed to snake stones 
are quite illusory. — Editor.] 

The Ancestry of the Elephants. 

Sir, — In the very interesting article on the above subject 
by Dr. Smith Woodward in the February number, I notice 
that he calls the fig. No. 6 on p. 13— (Head of Tetrabelodon 
angustidcus restored) — a fanciful sketch. As a matter of fact, 
there has been introduced into it a series of circular wrinkles 
evidently copied from those on the proboscis of the African 
elephant figured just above it. But it is clear that, as this 
proboscis was not pendent, no such wrinkles would appear. 
Moreover, it would seem more probable that its form would 
not be circular, but rather shaped to fit the elongated chin. 

In that case the mouth would act as a long pair of leathery 
tweezers, very suitable (with the help of the incurved tusks) 
for gathering in large mouthfuls of long, quick-growing marsh 
vegetation. The sharp incisors would enable this to be 
quickly cut off, and the ponderous animal could without delay 
move his weight on to firmer ground to masticate the food at 
leisure. 

As the species moved further north to harder ground and 
tougher vegetation, a more prehensile grip would be useful 
rather than a speedy way of gathering food together, whereas 
the incurved tusk and elongated mandible would not only be 
useless but highly inconvenient. Thus as the proboscis 
became longer and rounder, the lengthened chin disappeared 
entirely ; and the mammoth with its highly developed molars 
was able to subsist even on the hard and tough vegetation 
within the Arctic Circle. 

Herbert Drake. 

Verwood, Dorset, February 26, 19(^4. 

REVIEW OF BOOKS. 



Animal Studies, by David Starr Jordan, Vernon Lyman 
Kellog, and Harold Heath. (New York and London : 
Appleton and Co., 1903.) This admirable little treatise is one 
of the " Twentieth Century Text Books," and bears a very 
close resemblance to the volume on " Animal Life " — also of 
this series by the same authors — reviewed in the columns of 
"Knowledge" in igoi. It differs indeed, mainly, in the 
addition of several chapters on Classification ; and on the 
economic value and past history of animals. As an elemen- 
tary text book of Zoology it must take high rank among works 
of its kind, and will doubtless find a ready sale in this 
country. Here and there, however, great opportunities have 
been missed, and more or less serious mistakes are made. 
Thus, in the chapter on the Classification of Birds, the auks 
and pufiins are placed with the grebes and divers, the authors 
having been apparently led astray, like the older systematists, by 
the curious structural resemblance which these birds present 
in common. As a matter of fact, however, the resemblance 
to the grebes and divers which the auks, puffins, and guille- 
mots present are entirely adaptive. Their nearest relatives 
are, without question, the plovers and gulls. So, too, with 
the gulls and terns, these have nothing whatever to do with the 
petrels and albatrosses with which they are associated in this 
book. The resemblances which they severally present are 
again adaptive. It is equally misleading to place the owls 
with the accipiters. Turning to the mammals, we may remark 
that, as with the birds, the classification adopted is antiquated. 
Nevertheless, in spite of the defects to which we have drawn 
attention, the work is one which we can heartily commend. 

Pictures of Bird Life, by R. B. Lodge (Bousfield;, illustrated j 



27s. 6d. net. — Mr. R. B. Lodge has produced a most delightful 
book. The illustrations, which are very numerous, are all re- 
produced from his own photographs of birds and their nests 
taken from life. We see many such photographs nowadays, 
but none better than those reproduced in this book. There 
are eight full-paged plates reproduced by the three-colour 
process from photographs coloured by hand. We must con- 
fess that we would sooner have had these photographs with- 
out the colouring, which, in most cases, is not altogether true 
to Nature. The letterpress is interesting, and often very in- 
forming. Mr. Lodge has made the most of his opportunities, 
and tells us how and where he obtained his photographs. He 
has photographed birds in the Dutch marshes, Spanish inaris- 
mas, and Danish marshes and forests, and in many places in 
England besides. He gives many valuable hints to those who 
would take up bird-photography, and describes several in- 
genious devices and tricks which he has himself used with 
success. The most notable of these is his automatic electric 
photo-trap, whereby he traps the bird's portrait by hiding the 
camera and inducing the bird by bait or otherwise to touch a 
piece of silk, and thus set an electric battery at work to release 
the shutter of the camera. Many of Mr. Lodge's observations 
on the habits of the birds which he has watched so long and 
so closely while trying to secure their portraits are most valu- 
able. He may not have discovered much that was unknown, 
but his remarks are the result of direct and careful observa- 
tion, and this can never be without great value. There are 
several repetitions in the book which might have been avoided 
by more careful editing. The sentence, " The Hooded Crow 
I do not remember seeing so far south" (Enfield) (p. 124), 
might be put in a less ambiguous form. The bird is, of course, 
to be seen commonly further south than London. Mr. Lodge 
will find that the vibratory noise made by woodpeckers is 
heard not only in the spring (p. 138). But these are only 
small points, and are only mentioned in view of a possible 
second edition of this excellent book. 

BOOK NOTICES. 



The Grant and Validity of British Patents for Inventions, by 

James Roberts. .M..-\., LL.H. (John Murray, one vol. ; price 
25s.). This work has been written for and from the point of 
view of the inventor. It is intended to enable him to confine his 
claims to what can be supported and to avoid errors in his 
specification. The first part consists of the principles and 
rules affecting the grant and validity of British patents, and 
the practice respecting the atnendaient of specifications both 
before the Comptroller-General and the Law Officers of the 
Crown; the second part of abstracts of cases, illustrating 
the application of these priuciples; and the third part, the 
statutes and rules. The scope and tenour of the book are such 
as to make it useful to practising lawyers as well as to inventors. 

Mathematical Crystallography, by Harold Hilton, M.A. 
(Oxford : The Clarendon Press). Mr. Hilton's expressed 
purpose is to collect in this volume those results of the 
mathematical theory of crystallography which arc not provided 
in the modern text books on that subject in the English 
language. He includes a valuable summary of the geometrical 
theory of crystal structure which the labour of Bravais Jordan. 
Schneke, Fedorow. Schoenflics. and Barlow have now com- 
pleted. It is a student's book ; an advanced, but an extremely 
valuable one. 

Zoology, Descriptive and Practical. (Two Vols. D. C. 
Heath; price 4s. 6d. and 2S.) — The general plan of the 
volumes is to introduce each of the larger groups of animals 
by a careful study of a typical representative. 

BOOKS RECEIVED. 



The Naturalist's Directory (L. Upcott Gill) :— Introduction to 
the Study of I'hvsical Chemistry, by Sir William Ramsay— a 
wholly admirable allocution to stude'nts. (Longmans, Green.) 

Martins Up-to-DateTables of Weights and Measures. (T.Fisher 
Unwin.) 



April, 1904] 



KXOWLl'DGl-: lS: SClENTll'lC Xl-WS. 



75 



Modern Navigation, by W. H:ill. K.N. (Organised Scionce 
Sories.i L'niversitv Tutorial I'ross. _ 

SeconJ Stage Botany, by J. M. Lowson. (Organiseci Science 
Series. I Iniver^itv Tutorial Press. 

Entropv.bv lames Svvinbunu-. iConstable.l 

The .Modei Engineer Series.— X-rays, Simple Experiments n 
Electricity, The Locomotive, Acetylene Oas. ( IVrcn al Marshall.) 

A School Geometry. Tarts 1. IV.. by H. S. Hall: IV. and 
v.. F. H. Stevens. (Macmillan.) 

We have received from Messrs. Nalder Bros., ot \\ est- 
minster, their catalogue of Electrical Testing and Scientific 
Instrument!!. The catalogue is, in itself, an e.\trenuly in- 
teresting summary of the investigations now binng carried on 
in various departments of research, and special attention may 
be directed to the photometric apparatus. 



Tin following hocks an- in pnpurtttUm at the Claraulon Press i - 
Suess' •' Das Antlitz der Erde." authorised English transla- 
tion, by Dr. Hertha Sollas. edited by Professor W. J. Sollas, 
with preface by Professor Suess for the English translation. 
Koval i-vo. ,, , 

"Index Kewensis Plantarum Ph,anerogamarum. Supple- 

mentum secundum. 4to. 

Goebels -'Organography of Plants," authorised English 
translation, by I. Bayley Balfour, M..\., F.K.S. Vol. II. 
Roval Svo. 

Mr. Henrv Frou.dc u-ill also publish shortly :— 

•• \ History of the Daubenv Laboratory," bylK. T. Gunther. 




Conducted by F. Shillington Scales, f.r.m.s. 



Royal Microscopical Society. 

February 17, Dr. Henry Woodward, Vice-President, in the 
chair. An old microscope by Bate was exhibited, probably 
made early in the last century. Mr. Stringer contributed a 
paper on an attachment for reading the lines in a direct-vision 
spectroscope, and Mr. E. M. Nelson a paper on the vertical 
illuminator. The author said that, after lying in abeyance for 
25 years, the vertical illuminator had lately come into notice 
for the examination of opaque objects, and especially for the 
microscopical examination of metals. He criticised the four 
forms of this apparatus at present sold, namely, those known 
as the ToUes, Beck, Powell, and Reichert forms, and said 
that a vertical illuminator must not be an oblique illumina- 
tor, but must be capable of illuminating the full aperture of 
the objective with a parallel beam of light. It must not impair 
the use of the objective for ordinary work, and must, there- 
fore, not be a permanent attachment. The reflector must be 
placed near the back lens, and there must be some method 
for regulating the illumination. Mr. Nelson found that the 
Powell form, which, like Beck's, consists of a nosepiece con- 
taining a reflector, more nearly conformed to these conditions, 
but the reflector should be made much larger and the hole in 
the side of the nosepiece should be as large as the Society's 
gauge. To obtain the best advantage with vertical illumination 
oil-immersion ol>jectives should be used. The distance from 
the source of light to the mirror and thence to the objective 
should be equal to the distance from the eyepiece to the 
objective. At the hole at the .side of the nosepiece there should 
be a carrier for diaphragms of various sizes in preference to a 
wheel of diaphragms or an iris. There should also be a strip 
of metal with a slit in it which could be drawn across the hole 
in the nosepiece, and the direction of the slit should be in a 
line with the edge of the flame of the microscope l.uiip. 
Another paper l)y Mr. Nelson, "On the Influence of the Anti- 
point on the Microscopic Image Shown Graphically" was also 
read. The author referred to a papt^r in tlic Journal for 1903 
on "A Micrometric Correction for Minute Objects." wherein he 
stated by way of illustration that, if one of the minute spinous 



hairs on a blowfly's tongue was exaiuiiied on a bright ground 
and on a dark ground, a considerable difference in the sizes of 
the two images was diseeniilile, aiul that the diflerence was 
caused by anti-points. .\ talile was also given showing the 
amount to be ailded to the niicronietric ineasureinent of the 
image seen on the bright ground to bring it up to its true \ alue. 
Mr. Gordon, who had originated the theory of the anti-point, 
had made accurate drawings of the two images of the hair, 
and the ratio of the breadths of the hair in the drawings was 
as 45 to 05. Applying the corrections given in the table to 
the measurement of the apparent size of the hair on a bright 
ground, the actu.il size works out to 12 per cent. more. A 
ditference in the apparent size of objects when viewed on a 
bright or dark ground was recognised many years ago, but 
never explained, but M r. Gordon's admirable anli- point theorem 
has unlocked the riddle. Mr. Keith Lucas followed with a 
paper "On a Microscope with (Geometric Slides," the principle 
enunciated being .applied by the author of the paper to the 
fine and coarse adjustments' and to the sub-stage of a micro- 
scope, which was illustrated by lantern slides. 

The Qviekett Microscopical Club. 

The aniiu.il gem ral meeting was held on 1 i bruary 19 at 
20. Hanover Sipiar.-, the President, George Massee, ICsq., 
F.G.S., in the chair. .Xfter the usual business had been trans- 
acted, a ballot was taken resulting in the election of Dr. 
Edmund J. Spitta, L'.K.A.S., as President for the ensuing year. 
Mr. Frank P. Smith was elected Editor in succession to Mr. 
D. J. Scourfield, and Mr. Arthur Earland, Secretary. Dr. G. C. 
Karop, who has held the secretaryship for over twenty years, 
goes into well-earned retirement, carrying with him the grati- 
tude and esteem of all the ineml)ers. The other ofticers werc^ 
re-clectcd. 

The President delivered his annual address, dealing with 
the commoner fungoid diseases of garden trees and plants. 
These may be divided into two groups, according to whether 
the mycelium of the fungus is situated in the woody tissues of 
the plant ("perennial mycelium "), or whether only the season's 
growth, the leaves and fruit .are affected. The first division, 
of which the well-known " peach-curl " is an instance, is by 
far the more serious of the two, it being practically impossible 
to cure a plant which has become badly infected. In the 
second division, the plant becomes automatically purified, for 
a time, on the removal of the infected leaves, &c., either artifi- 
cially or in the course of nature, and if suitable measures are 
taken to prevent the germination of the spores in the following 
season, the plant may be wholly cured. Fire is the best 
destructive agent; the infected leaves should be burned. 
Spraying is ineffectual, for the mischief is under the surface, 
and spraying tends to spread the disease to fresh hosts by 
washing the spores off the infected plants. 

The chief causes of fungoid disease in cultivated plants are 
overcrowding and the use of chemical manures, which kill the 
nitrifying bacteria of the soil and stimulate the plant to an 
excessive and weakly growth. 

After the usual votes of thanks. Dr. Spitta was installed in 
the Presidential Chair, and in returning thanks for his elec- 
tion, referred t<i the analogy between the fungoid diseases of 
plants and the zymotic diseases affecting man, especially 
typhoid and diphtheria. 

It is an open secret among microscopists that the (.Hiekett 
Club's position at 20, Hanover Square has lately been some- 
what precarious, owing to the general rise in rents and the 
keen demand for accommodation in the building of the Royal 
Medical and Chirurgical Society. I am therefore glad to be 
able to say definitely that the Committee has succeeded in 
obtaining an extension of their tenancy in their old quarters, 
with retention of all their present accommodation, though at .1 
considerable increase of rent, which will, I trust, be justified 
by a corresponding increase of membership. To the amateur 
microscopist, especially the Londoner, the (Juekett Club, with 
its very low subscription of los. per annum, without entrance 
fee, offers many advantages. The announcement was made at 
the annual meeting that a new catalogue of the Club's fine 
library of about ijoo volumes was in course of publication, 
and this should still further increase the popularity of the 
Club. Applications for membership and inquiries relating to 
the Club should be addressed to the Hon. Secretary, Mr. A. 
Earland, 31, Denmark Street, Watford, Herts. 



76 



KNOWLEDGE & SCIENTIFIC NEWS. 



L, 1904. 



The Journal of Applied Microscopy. 

I am informed by Messrs. .\. E. Staler and Co. that the 
-American Journal of Applied Microscopy will be discontinued 
after the appearance of the November and December numbers 
of last year. This is a matter for sincere regret, as the journal, 
though distinctly technical, was a really valuable one. and it is 
unfortunate that it should not have met with sufficient support 
to justify its continuation. We are none too well supplied 
with microscopical literature, and it is strange that endeavours 
to provide for our deficiencies in this respect do not meet with 
more support. I fear that in the case of the journal referred 
to. the unfortunate and recurring arrears of publication, due. I 
believe, to the regrettable illness of the Editor, was respon- 
sible for the loss of no little support. Those of our readers 
who may wish to complete their sets may be glad to know 
that Messrs. Staley have a large number of back numbers in 
stock, and will be pleased to send them-to any subscribers for 
the sum of 2d. each. 

New Pond Life Tanks. 

Messrs. Flatters and Gamett. of Deansgate, Manchester, 
have sent me for inspection a new tank for the study of pond 
hfe. It is made of one solid piece of glass, and is not unlike an 
ordinan,- large goblet with flattened sides and square corners, 
standing on the usual round stem and foot. The sides are 
polished on the outside to prevent the usual distortion due to 
the une\ enness of glass, and the depth from front to back is 
such that an ordinary pocket lens can be conveniently used. ' 
The size of the tank sent to me was 4J inches high, 4 inches 
wide, and i, inch deep, and it was very steady. Leakage was 



of course impossible, the tank was easy to clean, and the price 
very moderate — namely. 3s. gd. I understand these tanks are 
made f inch high. liinch wide, and f inch deep at about half 
the price of the stand mentioned above, and also in a larger 
and more elaborate form, lined with opal glass and mahogany 
frame at the ends and bottom. 

Preserving Orthoptera. 

Mr. J. \V. Williams, M.R.C.S., F.L.S., writes to me. in con- 
nection with the note last month on preserving orthoptera, 
that he has found dipping the specimens into a weak solution 
of albO'Carbon in benzole is a better preservative against 
inould than the carbolic acid plan therein suggested, and a 
better curative also for mouldy specimens. Mr. Williams 
says he has tried this plan consistently with satisfactory 
results. 



"^i ><^ >^> >^> -^^ 

Chess Colviran. 



With reference to our note last month requesting 
opinions on this subject, we have to state that, having 
only received nine replies, of which seven were in favour 
of the retention of the Chess Column, we feel that the 
subject is not one of sufficiently widespread interest to 
warrant our devoting the space to it, and, therefore, we 
must, for the present at all events, discontinue the 
Notes and Problems. 



LAST YEAR'S WEATHER— APRIL, 1903. 



DISTRIBUTION OF MEAN TE.MPERATURE. 




RAINFALL. 



7 

3 0? 



^ p^ — -^ 
' 57 . y 

■JOk' 2 2S '2 °' 




^4^ 



The greneral distribution over Scotland differed from the 
normal, the isotherms ha\ing a north and south direction 
instead of west and eaj»t. Elsewhere the differences were less 
marked. T he actual \alues were, witliout exception, below 
the average the deficienc> as a rule being from 2- to 3;^=. 



Rainfall was ver>' irregular both as regards the quantit>' 
and the frequency, there being localities of excess and of 
defect in each district, iome stations having twice as many 
days with rain as others in the same neighbourhood. 



KDomledge & SeleDtifie Hems 



A MOXTIILV JOURNAL OF SCIENCE. 



Vol. I. No. 4. 



[new series.] 



MA\', 1904. 



r Entered at "1 
LStationers' Hall J 



SIXl'ENCH 



Contents and I\'otices. — See Page VII. 

Racdio-Activity OLnd 
R^QLdium. 



By W. A. Shenstone, F.R.S. 



1. 
\\ E owe the discovery of radioactivity, and therefore 
that of radium, to an accident, though the phenomenon 
itself might almost be said to be a common one. Radio- 
activity was first noticed by M. H. Becquerel, who, stimu- 
lated, perhaps, by Rontgen's brilliant discovery of tie 
X rays, was looking, in 1S96, for yet other new radiations. 

The accident was as follows : There is a salt known as 
potassium and uranium sulphate which, when it is exposed 
to sunlight, becomes for a moment self-luminous, and 
Becquerel was studying this phenomenon photographic- 
ally. 

His experiment consisted in placing crystals of the 
salt above photographic plates well protected from light 
by means of black paper, and then exposing the salt, 
which was outside the black paper, to the direct light of 
the sun. When he did this it became evident that some 
radiation or some emanation was produced which could 
penetrate the paper, for the photographic film immediately 
below the salt was so acted upon that when the plate 
was developed he obtained a silhouette of the crystals 
more or less like that shown in fig. i, though this par- 
ticular silhouette was given by a little radium bromide, 
and not by the uranium salt studied by Becquerel. 




Fig I. — Silliouetti given iv Radium, 

One day, just as everything was ready for an experi- 
ment, clouds covered the sun, and Becquerel put away 



his plates with the crystals upon them, thinking them 
spoilt. Several days afterwards liedevcloped the plates and 
found to his surprise that thesiliioucttes were particularly 
strong ones. lie found, in short, that the sun was not needed 
to stimulate the salt; that this latter, without any such 
stimulant, radiated or emitted something which was able 
to penetrate black paper and act likr light on a sensitive 
photographic plate. Me found as the result of further 
experiments that this was no temporary quality of the 
salt. It persisted for days and months, and, as he dis- 
co\-cred subsequently, even for years. I'"urther, the same 
power was possessed by other uranium salts and by the 
metal uranium. Anyone who can take photographs can 
verify all this for himself quite easily. 

The radiations thus discovered by Becquerel are called 
■'Becquerel Rays." They resemble the Riintgen rays in 
many respects, and at one time were regarded as due to 
Rimtgen rays. Thus, they cause damp dust free air to 
deposit fog, make air conduct electricity, will pass througii 
such substances as paper, glass, paraffin, quartz, sulphur, 
Iceland spar, and thin layers of metal e\en more freely 
than Rontgen rays, and they cannot be reflected, re- 
fracted, nor polarized like the waves of which ordinary 
light is composed. It was found, further, that they are 
not homogeneous, but consist of several different 
radiations which can be filtered off from each other as it 
were, and can then be distinguished by their separate 
characteristics. 

Bodies which emit these remarkable radiations are 
said to be " radio-active." As we shall see presently, 
other metals besides uranium are radio-active, and also 
the waters of some springs, as, for example, the waters 
at Bath, and even solid earth. 

Becquerel's great disco\-ery soon proved prolific. It 
suggested to Madame Sklodowska-Curie the idea that 
the great radio-activity of specimens of pitchblende, 
which exceeded that of the uranium present in them, nuist 
be due to special constituents, and so in her hands and 
those of others led to the discovery of polonium, radium, 
and actinium. And the remarkable properties of these 
new substances in their turn have started new ideas or 
revived old ones in several departments of science. 

Madame and Monsieur Curie and their colleague, M. 
Bemont, discovered polonium and radium, and INI . Debierne 
was the discoverer of a third substance of the same class, 
actinium. The method of working was to separate the 
components of the pitchblende, which is a very complex 
mineral, and to study the radio-active power of each con- 
stituent. The results obtained with the bismuth and 
barium from this mineral arrested attention, and presently 
it was found that the former was associated with the sub- 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



stance now called polonium, and the latter with the radium 
which plays such an important part in modern science. 
Neither polonium nor actinium have as yet been isolated 
in the form of a salt. The former in many ways resembles 
bismuth, and its nature still remains doubtful. Radium, 
on the other hand, yields salts — e.g., a bromide, a chloride, 
and a nitrate. Its combining weight has been fixed by 
Madame Curie at 112-5, and 225 is suggested for its 
atomic weight. Itexhibitsadefinite flame spectrum, which 
has been recorded by Messrs. Runge and Precht, and 
which is given in fig. 2, whilst its spectrum in the ultra 
violet has been studied by Sir William Crookes and 
others, and affords a means 'of idcntilying it. 






Fig. 2, — The Flame Spectrum of Radium. 
The line <i has the wave length 4S26, b 6329, c 6349, d 6653. There 
are bands about b c and <i as shown above. 

Radium is generally regarded as an element, but as the 
total quantity of the pure radium salts yet made would be 
insufficient to fill a small egg cup, this statement must 
still be taken with some reserve. The so-called pure 
salts of radium possibly may be mixtures, but, for the 
present, in the absence of any evidence to the contrary, 
we may assume them to be salts of a new and peculiar 
elementary substance radium. 

Radium the element has not been isolated. Its salts 
are so valuable, and the process of separating it probably 
would be so wasteful, that it seems unlikely anyone will 
attempt to prepare elementary radium at present. 

The process of purifying a radium saU has not been 
very frequently described, but it is simple enough in 
principle. The raw material is the residue left after the 
uranium has been extracted from pitchblende. A ton of 
this material suitably treated may yield 10 or more kilo- 
grams of a mixture consisting chiefly of the sulphates of 
barium, lead, iron, and calcium, with a trace of radium. 
This is converted into carbonates by heating it with a 
solution of carbonate of soda, and the carbonates are 
dissolved in hydrochloric acid, which converts them into 
chlorides. The lead and iron in the mixture of chlorides 
thus produced are got rid of by means of sulphuretted 
hydrogen and ammonium sulphide, and the remaining 
barium, calcium, and radium are reprecipitated as car- 



• 



Fi<;. 3. — Kailiographs of radium salt and uranium taken 
siniultaneouslv. 



bonates, again converted into chlorides, and then washed 
with strong hydrochloric acid to remove the calcium 
chloride. The residue consists of barium chloride con- 
taining a trace of radium chloride. This is dissolved in 
hot water and allowed to crystallize partially. The 
crystals, which contain most radium, are separated 
from the liquid portion, and the latter is then 
evaporated to recover the remaining salt, and each of the 
two portions thus produced is similarly fractionated. By 
systematic work of this kind products were obtained first 
nine hundred times as radio-active as uranium, then five 
thousand times as active, then fifty thousand times, and 
at last, it is said, a million times as active as the stan- 
dard substance, the removal of the barium salt at the 
later stages being facilitated by using solutions of hydro- 
chloric acid in place of water for dissolving the mixture 
of barium and radium chloride. 

Some idea of the difference between the activity of 
uranium salts and of radium may be got from fig. 3. 
On the reader's right is the silhouette a, given by 
one-sixth of a grain of radium in fifteen minutes. The 
area about the faint dark mark above b a little to 
the left of this shows the effect of a much larger quantity 
of a uranium salt, the two being exposed side by side 
over the same plate. The uranium salt, as will be seen, 
gave no sensible result at all. The small dark mark 
above b was added to indicate the centre of the area 
exposed to the uranium. 

The salts of radium, in their ordinary reactions, 
resemble those of barium rather closely, but in other 
respects they are remarkably different. Thus, they are 
visible in the dark, and continuously evolve heat ; so 
that a heap of a radium salt is always hotter than the 
air around it. So great is the amount of heat evolved 
that a gram-atom of radium gives out in a year as much 
heat as a gram-atom of hydrogen when it is burnt in the 
oxyhydrogen flame, and, moreover, as far as we know, 
the radium would go on giving out heat at this rate for 
many centuries. Its powers are destroyed to a great 
extent if it is strongly heated (see emanation), but are 
recovered spontaneously after a few weeks on cooling. 

Radium, or rather its radiations, are very destructive. 
A piece of cambric placed above a box containing a 
little radium salt was found by Lord BIythswood to be 
pierced with holes after two or three days. A photo- 
graphic film exposed to one-sixth of a grain of radium 
bromide in the author's laboratory for four hours by Mr. 
W. D. Rogers (who has kindly prepared many of the 
figures given in this article) yielded no silhouette because 
the film was completely disintegrated and its remains 
washed away during the developing process ; and the 
caustic powers of radium salts, as is well known, are 
thought likely to prove useful in surgery, and have some- 
times produced very unpleasant effects when specimens 
of the salts have been kept too long near the human body. 
Its power of making air conduct electricity is shown by 
the way in which a tassel of silk electrified by rubbing 
with india-rubber collapses when radium is brought near 
it, and by the rapid collapse of the lea\-es of a charged 
gold leaf electroscope under similar circumstances. But 
the prettiest way of observing this property of radium 
is as follows ; — 

Connect a spark gap at b, fig. 4, with an induction 
coil and with a vacuum tube a — a large vacuum 
tube gives the best result — as in the following figure. 
Arrange matters so that the coil gives a very steady 
discharge at the spark gap, and then draw back the 
point and plate till the discharge just passes through the 
vacuum tube, only an occasional spark crossing at b. 
Then bring the radium close to the spark gap. When 



M 



\Y. I904..J 



KNOWLEDGK & SCIENTIFIC NEWS. 



79 



you do this the vacuum tube will go out and the discharge 
will not be re-established at the spark gap till you remove 
the radium salt. 




V\g. 4- 

The coil must not give too strong a discharge, and the 
discharge must be very steady. If this is secured, the 
experiment can be brought off with great certainty every 
time. 

{To be coniinufd.) 

Modern Views of 
CKemistry. 

By H. J. H. Fenton F.R.S. 



A FEW further illustrations may be given of the simple 
explanations which the ionic-dissociation hypothesis 
affords of the properties and reactions of salts in solution. 
Smce salts are highly ionised when dissolved in even a 
moderate quantity of water, the properties of the solution 
represent the joint or added properties of the ions into 
which the salt has split up. The colour of the solution, 
for example, is that of its ions ; solutions of most common 
cupric salts are blue and nickel salts green. This is 
because the acid-radicles (sulphate, nitrate, &c.) happen 
to give colourless ions and the colours observed are 
therefore due to the metallic ions. Most permanganates 
are pink and manganates green in solution, because the 
metallic ions (potassium, sodium, &c.) happen to be 
colourless and the colours here are due to the acidic ions. 
It is interesting to observe in this connection that some 
ions may be correctly represented by the same chemical 
symbol and yet show different colours and other proper- 
ties in solut'on. Both the manganate ion and the per- 
manganate ion are represented by the symbol ^MnOj, 
yet one is green and the other pink. The copper 
ion again is blue when in the cupric state, but colour- 
less in the cuprous state. This is explained by saying 
that the electric charge associated with the ion is 
different in the different states. A well known and 
simple experiment in illustration of the above views may 
be made as follows : Dissolve some dry cupric chloride, 
which is brownish yellow, in a very little water ; the 
solution appears green. Dilute it, and it becomes blue ; 
add a strong solution of hydrochloric acid or sodium 
chloride and it turns green again. Repeat the latter part 
of the experiment, using mercuric chloride instead of sodium 
chloride, and the solution remains blue. The "ionic" 
explanation is that the very strong solution first made 



contains some molecules of cupric chloride (impure 
yellow) mixed with copper ions (blue) and tliis mixture 
gives to the eye the appearance of green. On diluting, 
the cupric chloride molecules are further ionised, giving 
therefore less yelk)w and more blue. If, however, a 
strong solution of a metallic cliloride is added, its chlorine 
ions, being in great concentration, prevent the further 
ionisation of the cupric chloride, according to well known 
principles which will be discussed later. It happens, 
however, that mercuric chloride is an exceptional salt in 
that it is only very slightly ioniseil when it is dissolved in 
water; there are scarcely any free ciilorine ions in its 
solution therefore, and it can have little influence in 
checking or reversing the ionisation of the cupric chloride. 

The colour-changes of the indicators which are used 
in analysis, such as litmus, may be explained in a similar 
way. We may regard these indicators as behaving like 
very weak acids and the colours they show in acid solu- 
tions, where they are very little, if at all, ionised, is the 
colour of the compound or molecule — red in the case of 
litmus. But now on adding an alkali a salt is formed, 
and this, like nearly all salts, is highly ionised in solution, 
so lliat we now see the colour of the acidic ion — blue in 
the case of litmus. The colour-changes of other well- 
known indicators can be similarly explained ; in phenol 
phthalein the molecule is colourless, tlie acidic ion pink, 
wOiereas in the case of methyl-orange the molecule is 
pink and the acidic ion yellow. 

rrhis very simple and attractive cxphuiation of the 
colour-changes in indicators has, it must he confessed, 
received rather a severe " shaking " owing to certain 
recent observations, and it is probable that the effects 
depend rather upon changes of constitution in the indi- 
cator.! 

Not only th^ colour but the reactions of a solution of 
a salt are considered to be due to its ions; a solution of 
ferrous, or ferric chloride, for example, gi\es a precipi- 
tate with alkalis due to the iron ion and a precipitate 
with silver nitrate due to the chlorine ion. Potassium 
ferrocyanide, however, gives no precipitate with alkalis, 
although it contains iron, and chloral gives no precipitate 
with silver nitrate although it contains chlorine. The 
potas-iuni ferrocyanide contains its iron associated with 
cyanogen as a complex group, and when dissolved gives 
potassium ions and ferrocyanide (l'eCr,N(,) ions; none of 
the iron, as such being present in the ionic state. Cliloral 
again gives a solution which contains no chlorine ions ; 
the chlorine is combined with the other elements as an 
undissociated molecule. 

Mercuric cyanide has long been known as abnormal in 
its behaviour, since it answers scarcely any of the usual 
tests either for mercury or for a cyanide. It can he shown 
in \arious ways, however, that the salt is practically dis- 
solved unchanged ; its solution contains neither mercury 
ions nor cyanide ions. The poisonous character both of 
mercury salts and of cyanides is assumed to be due to 
their ions ; therefore we should expect mercuric cyanide 
to be non-poisonous. This is stated to be the case, 
although it does not appear that any ardent supporter of 
the " ionic " theory has had the strength of mind to try 
its effects upon himself. 

The most "chemically active" substances then in 
solution are those which are most ionised. It does not 
follow, how^ever, that all chemical changes which may 
take place in solution are necessarily ionic changes. It 
has been shown, for example, that certain salts and acids 
undergo immediate double decomposition when dissolved 
in solvents in which no ionisation occurs. 

The action of a strong acid upon the salt of a weak 
acid was formerly looked upon, as indicated above, as 



So 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



due to the strong acid appropriating the base and turning 

the weaker acid out. For example — 

Sodium acetate + hydrochloric acid = sodium chloride + 

acetic acid. 
But the ionic view is quite different. Here we assume 
that sodium ions + hydrogen ions + chlorine ions + 
acetic ions give sodium ions + chlorine ions + slightly 
ionised acetic acid, the change consisting in the union of 
hydrogen ions with acetic ions, the others remaining 
unchanged. 

It is well known that many salts which are "normal " 
in the chemical sense yet give an acid or an alkaline 
reaction \vhen dissolved in water. Thus sodium borate 
or sulphite shows an alkaline reaction, whereas aluminium 
sulphate or ferric chloride react acid. This may be ex- 
plained by assuming that the salt is partly hydrolysed by 
water in the first instance, giving acid and base in equi- 
valent quantities. But if the base is strong and the acid 
is weak the former will be largely, and the latter slightly, 
ionised ; so that the solution will contain an excess of 
hydroxyl over hydrogen ions, and will therefore react 
alkaline. If the base is weak and the acid strong, there 
will, for similar reasons, be an excess of hydrogen over 
hydroxyl ions, and the solution will be "acid." 

Many of the ordinary chemical changes may be repre- 
sented as consisting in an exchange of electric charges 
between the ions, or in the assumption of charges by 
neutral substances whereby they become ionic, and a 
corresponding loss of charges by the ions whereby they 
become " ordinary " or neutral substances. When dilute 
hydrochloric acid acts on zinc, for example, the metal 
passes into the ionic state, assuming positive charges ; 
whilst the ionic hydrogen gives up its positive charges, 
liecoming ordinary hydrogen gas, the chlorine remaining 
in the ionic state throughout. When stannous chloride 
is converted in stannic chloride, in solution, by chlorine, 
the change may be regarded as consisting in the assump- 
tion of two additional positive charges by the tin ion and 
the assumption of two equal and opposite negative charges 
by two atoms of neutral chlorine, which thereby becomes 
ionic. In this action the tin is said to change its valency 
from two to four (;.f., from the stannous to stannic form), 
the valency, in fact, being in this sense measured by the 
number of unit charges with which the atom is associated 
when in the ionic condition. 



Modern Cosmogonies. 

VIII.— Protyle: Wha.t is it ? 



The la.te Mr. H. C. FYFE. 



1 1 is with the deepest regret that we have to record 
the death of one of our contributors, Mr. Herbert 
Fyfe. Mr. Fyfe was only thirty years of age, and 
his death, though not entirely unexpected, was 
none the less sudden. He leaves a gap in scientific 
journalism that none can fill as well as he. Pos- 
sessed of extraordinary industry and energy, and 
gifted with a quite unusual capacity for assimilating 
the mam details of the matter in hand, he wrote 
articles on many subjects besides the one which 
was his chief interest — " Submarine Warfare " — 
and his work never missed its mark. The loss to 
scientific journalism is great; but the loss to his 
wide circle of friends is irreparable. One of the 
kindest and most generous of men, one of the most 
helpful of colleagues, he leaves behind him a 
memory not alone of goodness of heart or sound- 
ness of mental fibre, but of a moral nature that was 
a great example of courage and sweetness. 



By Miss Agnes Clerke {Hon. Mem.), F.R.A.S. 

The notion of a primordial form of matter meets us at 
every stage of cosmogonical speculation. It is the out- 
come of an instinctive persuasion that, if we could only 
" lift the painted \e\\ " of phenomena, the real business of 
the universe would be found to be proceeding in the 
background, on a settled plan, " without haste or rest ;" 
that uniformity is fundamental, diversity only inciden- 
tal ; and that the transformations of the one simplified 
substance might be represented by a single formula, the 
discovery of which would place in our hands the master- 
key to the locked secrets of the universe. Among 
untutored thinkers, some familiar kind of matter, idealised 
and generalised, commonly stood for the typical world — ■ 
stuff". Water was the first favourite. Thales, the "wise 
man " of Miletus, procured his Cosmos by precipitation 
from an aqueous solution, and many savage tribes have 
de\ised analogous expedients. Anaximenes preferred 
air for the universal solvent ; Heracleitus substituted 
fire, and set on foot a scheme of what is now often 
designated " elemental evolution." From the perpetual 
" flux of things," he conceived that the four substances 
selected by Empedocles as the bases of Nature were not 
exempt ; and a fragment of his scheme survived in 
Francis Bacon's admission of the mutual convertibility 
of air and water. In the main, howexer, the author of 
the " Novum Organum " adhered to the Paracelsian 
doctrine of an elemental triad,- while rejecting the saline 
principle, and retaining, as the material substratum, 
sulphur and mercury. f 

These twilight fancies faded in the growing light of 
chemical science ; yet the mental need that they had 
temporarily appeased survived, and had somehow to be 
satisfied. An " Ur-Stoft " was still in demand ; but the 
nineteenth century characteristically attempted to supply 
it by weight and measure. Dalton's combining equiva- 
lents afforded the warrant for Prout's hydrogen hypo- 
thesis. The problem to be faced was to find a unit-atom 
by the varied combinations of which all the rest of the 
chemical atoms might be formed. The condition indis- 
pensable to be fulfilled was that their weights should be 
exact multiples of that of the unit, and it came near to 
fulfilment by the hydrogen-atom or semi-atom. It was, 
nevertheless, a case in which approximate agreement was 
of no avail ; the adverse decision of the balance finally 
became unmistakable ; and Prout discreetly fell back, in 
1831,1 upon the resource of deriving hydrogen itself 
•' from some body lower in the scale." His hypothesis, in 
short, dissolved into a conjecture. It had only emphasised 
the stipulation that the " Protyle" of the ancients must 
be sucli as would likewise serve for the unification of all 
the chemical species. 

Meanwhile, the theoretical search for it had been 
carried on in widely different fields of inquiry. Laplace's 
speculations, Herschel's observations, had led to the con- 
ception of some kind of " fire-mist" as the genuine star- 
plasm. But its nature and properties remained indefinite, 
or were assigned at the arbitrary choice of adventurous 

' First introduced by Basilius Valentinus. See Fowler's Novum 
Orgiiinim, p. 57C. note. 

t Thus recurring, as Mr. I'owler remarks (loc. cit.), to Geber's 
earlier view. 

I Dut of Nalioiuil Ihoj^Viiplty, V I .\L\'I , p 426. 



M.A 



1904.J 



KNOWLEDGE & SCIENTIFIC NEWS. 



cosmogonists. So the " shining fluid " of space was 
"everything by turns and nothing long," until Sir 
Wilham Muggins, in 1S64, o'l^'^^' 't spectroscopic indi- 
viduality. The " recognition -mark" of nebulium is a 
vivid green ray, by the emission of wliich it is known to 
iiave a concrete existence, ^'et th,' little that has besides 
been learned about it discountenances its identification 
with the mattria informis of anti(iue philosopliy. This we 
should e.xpect to be the subtlest of all substances. Pro- 
fessor Campbell, however, has gathered indications tliat 
nebulium is denser than hydrogen. Its luiiiinosity, at 
least, which is invariably associated with that of hydro- 
gen, extends further in the same formations; it seeks a 
lower level. The nebulium-atom is not, then, the 
chemical or the cosmical unit. 

This evasive entity, or something that curiously simu- 
lates it, has proved to be of less recondite origin. Sir 
William Crookes is amply justified in claiming the 
venerable designation of Protyle for the " radiant mat- 
ter " first produced in his vacuum-tubes nearly thirty 
years ago. The discovery was astonishing and unsought ; 
and its significance has not yet been measured. Matter 
assumes the " fourth state," in which it is neither solid, 
liquid, nor gaseous," under the compulsion of an electric 
discharge in high vacua. At an exhaustion of about 
one-millionth of an atmosphere, the manner of its transit 
abruptly alters. Conduction gives way to convection. 
Luminous eflects are abolished. The tubes cease to 
glow with brilliant, parti-coloured stria; the poles are 
no longer marked by shimmering halos or brushes ; 
only a green phosphorescence is seen where the glass 
walls of the receptacle are struck by the stream of pro- 
jected particles. They come, with half the velocity of 
light, exclusively from the negative pole, the positive 
pole remaining inert. Hence the name " cathode-rays." 
bestowed by Goldstein on the carriers of electricity in 
highly-exhausted bulbs. 

These mysterious, sub-sensible agents possess certain 
very definite properties. Their paths are deflected in a 
magnetic field ; they can traverse metallic films ; and 
their investigation in the open, thereby rendered feasible, 
has shown them to possess photographic efficacy, and 
the faculty of l)reaking down electrical insulation ; more- 
over, they transport a negative charge of fixed amount, 
and have a determinate momentum. They are then 
assuredly no mere pulsations of the ether ; unless our 
senses " both fail and deceive us," their quality is ma- 
terial. Material, yet not quite with the ordinary 
connotation of the term. The most essential circum- 
stance about the cathode-rays is that they remain un- 
modified by the chemical diversities of the originating 
gases. t X hydrogen tube yields identically the same 
radiant matter as an oxygen or a nitrogen tube. Here 
then at last ^ve hav'e within our grasp undifferentiated 
substance — matter not yet specialised, neither molecular 
nor atomic, matter destitute of affinities, exempt from 
the laws of combination — matter in its inchoate, and 
perhaps ultimate, form ; in a word, the far-sought 
Protyle. 

Already, in 1879, Sir William Crookes conjectured the 
infinitesimal missiles propelled from the cathode to be the 
" foundation-stones of which atoms are composed." i 
.■\nd in 1S86 hejpronounced them more decisively to be 
the raw material of atoms, which, to Sir John Herschel's 
apprehension, bore the unmistakable stamp of a " manu- 

• Crookes, I'bil. Trans. Vol. CLXX , p. 1O3 

t J. J. Thomson, The Discharge uf Ehclricilv through Gases, p. 195 ; 
Phil. Mag. Vol. XLIV. . p. jii , 

j Science, June 26, 1903. 



factured article." Nor did his recent commentator re- 
frain from attempting distantly to divine the method of 
their construction, or from laying his linger on the by- 
products and residues associated with it,' , although \\{\ 
felt compelled to relegate the cosmic factory to the edge 
of the world, where inconcei\'al)le things may happen. 
All this, indeed, seemed, in the late Victorian era, like 
mounting the horse of Astolfo for a trip to the moon ; and 
sane common-sense pronounced it fantastic enougli to 
" make Democritus weep and Heracleilus laugh." I Hut 
we have since learned from Nature hersell some tolerance 
of audacities. 

Step by step, the new order uf ideas has irresistibly 
come to ihe front. It owed Us origin to Sir William 
C'lookes's skill in producing high vacua, and the con- 
secjuent development in his tubes of radiant effects. 
Then, in 1879, uni\ersal importance was claimed for 
them, and matter in the ''fourth state," by a revival of 
the dreams of the ancients, expanded into a kind of 
visionary Protyle. Philipp Lsnard made the next ad- 
\ance towards its actualisation by slipping it, in 1894, 
through an aluminium window, and watching its 
behaviour towards ordinary matter. Two years later, 
l^bntgen-rays made their entry on the scene ; and before 
the end of 1896, Becquerel, hurrying along the track of 
novelties, came upon the momentous discovery of radio- 
activity. 

A revision of ideas has ensued. Some time-honoured 
assumptions have had to be discarded ; so-called laws 
have been found to need ijualification ; the (jid system of 
physics is consequently out of gear, and much time and 
patient labour must be expended upon the adjustment of 
the new and improved system destined to replace it. The 
leading and indisputable fact of the actual situation is 
that a number of hitherto unsuspected modes of energy 
lia\e been disclosed as widely operative in Nature. All 
are of a " radiant " character. They travel in straight 
lines with enormous speed ; they start from a material 
base, and pr(.)duce their several effects on reaching a 
material goal. Now these effects are closely analogous, 
notwithstanding that the rays themselves are radically 
dissimilar. Those of the cathodic kind are corpuscular. 
They consist of streaming particles, each, according t(j 
Professor J. J. Thomson, of about one-thousandth the 
mass of the hydrogen-atom. Others — the noted "alpha 
rays " — are atomic ; they are supposed to aggregate into 
helium. Finally, the Ii<)ntgen variety are ethereal ; they 
are composed of light-vibrations reduced in scale, and 
augmented correspondingly in frequency. What is most 
remarkable is that these various forms oi activity gise 
rise, by different means, to very much the same results. 
They are, in fact, distinguishable only by careful observa- 
tion. They possess in common, though not to the same 
degree, the faculties of penetrating opaijue matter, of 
impressing sensitive plates, of evoking fluorescence ; 
while under the impact of cathode and Rontgen rays, as 
well as of ultra-violet light, insulated electric charges 
leak away and evanesce. There is, however, one clear 
note of separation between cathodic and X-rays in the 
sensibility of the former, and the indifference of the latter, 
to magnetic intiuence. Thus alone, it would appear, is 
electrified matter set apart from what we call ether. If 
tlying corpuscles could be obtained in a neutral condition, 
the distinction would vanish. But this is evidently im- 
practicable. Indeed, advanced physicists abolish the 
material substratum of the corpuscle, and assign its attri- 
butes to the associated atom of electricity. It is, at any 

* i'roc. Chem. Sociely, March 28, iSSJi. 
t Times, Marcli 30, 1888, 



82 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



rate, undeniable that the cIclUil.lI relations of matter 
become more intimate as our analysis of its constitution 
goes deeper. Ether, electricity, matter, all seem to merge 
together in the limit; their distinctions ultimately evade 
definition. So animal and vegetable life appear to coalesce 
in their incipient stages, and de\elop their inherent differ- 
ences with ad\ance towards a higher perfection. 

The various branches of inorganic nature, too, possibly 
spring from a common stock. C)ur powers of discrimina- 
tion fail to separate them as we trace themdownward ; 
but that may he because of the inadequacy ofthe guidirg 
principles at our command. A larger synthesis is de- 
manded for the harmonising of multitudinous facts, at 
present grouped incongruously, or left in baffling isola- 
tion, and it is rendered increasingly difficult of attainment 
by the continual growth of specialisation. Year by year 
details accumulate, and the strain of keeping them under 
mental command becomes heavier ; yet what can be 
known must, in its essentials, be known as a preliminary 
to extending the reign of recognised law in Nature. 

Sooner or later, however, the wealth of novel expe- 
rience recently acquired will doubtless be turned to the 
fullest account. Just now, we can grasp only tentatively 
its far-reaching implications. They have a very im- 
portant bearing on the hoary problem of the genesis of 
visible things. The (juestions of what matter is, and of 
how it came to be, have been cleared of some of the 
metaphysical cobwebs involving them ah aniiquo, and 
insistently crave definite treatment by exact methods. 
We should, indeed, vainly aspire to reach — or to com- 
prehend, even if we could reach — an absolute beginning. 
To quote Clerk Maxwell's words : " Science," * he wrote, 
"is incompetent to reason upon the creation of matter 
itself out of nothing. We have reached the utmost limit 
of our thinking faculties when we have admitted that, 
because matter cannot be eternal and self-existent it 
must have been created." The discovery that atoms 
disintegrate into corpuscles does not then bring us any 
nearer to the heart of the mystery ; but it is eminently 
suggestive as regards secondary processes. 

Acquaintance with ultra-atomic matter, begun within 
the narrow precincts of " Crookes' tubes," has advanced 
rapidly since " radiology " took its place among the 
sciences. For, from the time when Becquerel first saw 
a plate darkened by the photogenic projectiles of 
uranium, and Madame Curie sifted radium from the 
refuse of the mines of Joachimsthal, the lines of proof 
steadily converged towards the conclusion that chemical 
atoms are not only divisible, but that their decay pro- 
gresses spontaneously, irresistibly, in fire, air, earth, and 
water, as part of the regular economy of Nature. To 
explain further. Radio active bodies are composed — 
according to Rutherford's plausible hypothesis — of atoms 
in unstable equilibrium. The gradual changes incidental 
to their own internal activities suffice to bring about 
their disruption. And their explosi\'e character is ob- 
viously connected with their unwieldy size, since 
uranium, thorium, and radium, the three substances pre- 
eminent for ladio-activity, possess the highest atomic 
weights known to chemistry. The precarious balance, 
then, of each of these complex, though infinitesimally 
small, systems is successively overthrown, regardless of 
external conditions or environment, their constituent 
parts being hurled abroad with .the evolution of an 
almost incredible amount of energy. Their products 
include cathode-rays; matter in the "fourth state," 
matter a thousand times finer than hydrogen, is ejected 
in torrents from the self-pulverised atoms of radium. 

* Ency. Brit., ait. Atom. 



Moreover, the issuing rays are equivalent to currents of 
negative electricity. Each corpuscle bears with it an 
electron, or is itself an electron ; for the choice between 
the alternatives is open. In either case, we are con- 
fronted with matter apparently in its ultimate form ; and 
to that form ordinary, substantial bodies tend to become 
reduced. Electrons may fairly be called ubiquitous. 
They occur in flames, near all very hot masses, wherever 
ultra-violet light impinges on a metallic surface" ; they 
are freely generated by Rcintgen and cathode rays ; they 
are the agents of electrical transmission in conductors. 
Everywhere throughout the universe, then, atoms are in 
course of degradation into corpuscles. But no informa- 
tion is at hand as to the scene or mode of their reconsti- 
tution. The waste and decay are patent ; the processes 
of compensation remain buried in obscurity. Indeed, 
Sir William Crookes anticipates the complete submer- 
gence, at some indefinitely remote epoch, of material 
substance in Protyle, the " formless mist " of chaos. He 
assumes an identity between the past state and the future, 
leaving, however, the present unexplained. The break- 
up of matter, in fact, does not render its construction the 
more intelligible. Running-down is an operation of a 
different order from winding-up. It is an expenditure of 
a reser\e of force. It needs no effort; it accomplishes 
itself. But to create the reser\-e for expenditure demands 
foresight and deliberate exertion ; it implies a designed 
application of power. Now each atom is a store-house 
of energy representing the force primitively applied to 
reduce some thousands of free electrons to the bondage 
of a harmoniously working system. Its disruption is 
accompanied by the dissipation of the energy previously 
accumulated in it ; and that atomic systems are not cal- 
culated for indefinite endurance is one of the most sur- 
prising of modern discoveries. The secret of their 
original construction is, nevertheless, still impenetrable. 
That they are composed of Protyle — that their clustering 
members are corpuscles moving under strong mechanical 
control — is more than probable. And the law of order 
adumbrated by what are called the " periodic " relations 
of the chemical elements shows that their concourse was 
very far from being fortuitous. But beyond this point, 
there is no holding-ground for definite thought. \\'e are 
ignorant, too, whether the process of building matter out 
of Protyle is at present going on, or was completed once 
for all in the abysmal fore-time, decay being now defini- 
tive. Nor is it likely that we shall e\er succeed in cap- 
turing with recognition a brand-new atom freshly minted 
for cosmical circulation. 

' Fleming, P/Df. A'l^ii/ /«s///H(f, Vol XVII., p. 169. 



A Free Public Reference Library, having distincti\e charac- 
teristics, is in course of formation by the London County 
Council at the Horniraan Museum, Forest Hiil. The primary 
intention is to encouratje the study of Geology and the biolo- 
gical sciences (Botany, Zoology, and Anthropology') — especi- 
ally as represented in the Horninian Museum collections — by 
providing the best books on these subjects, more particularly 
the works of admitted authority which, by reason of cost and 
a relatively small demand, are not ordinarily found in libraries 
freely accessible to the general public. Although undue im- 
portance is not attached to merely descriptive works, a dis- 
tinctive feature of the library is the prominence given to the 
special books necessary to a detailed study of any section of 
the Archa-ology or the Natural History of the British Islands. 
Text-books. manuaL, and monographs are supplemented by 
works on the theoretical aspects of every branch of science 
with which the library is concerned, and books designed to 
stimulate individual observation and inquiry, including the 
most recent manuals, British and American, of " nature- 
study," are liberally provided. 



May, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



83 



Animated Photographs 
of PloLrvts. 



Hy Mrs. Dlkini-ikld H. Scott. 



The kinematograph has now been in use for many 
years for successfully reproducing rapid movements of 
living objects, such as the boat-race, an express train 
in motion, or the Coronation procession. "Its use for 
showing, at an accelerated speed, sloh' movements which 




the screen and tin- spectators can liavc tlic pleasure 
of seeing the earth rriisixl up by the swelling seed, the 
seed-coat thrown ofi", the seed-heaves emerge, straighten 
themselves out, and then the lirsl leaves burst forth. 

If the plant is a climbing one such as tlie I'rench l>ean, 
another plate will show the point of the stem swaying 
round in large circles till it comes into contact with its 
support, and twines round and round the stick provided 
for it. Professor Pfeffcr, of Leipzig, in 1900, devised a 
\-ery perfect apparatus of this sort for class demonstra- 
tion, the photographs being taken by electric light with 
a film kineniatotjraph. I'.ul the expense of this appa- 



Sparmannia a.fricana. 




•MiKiS 



I IK. 14. 



t"'S- IS- 



1 1 shows the general appearance of 
the inflorescence, taken at 5 a.m. 
riowers just opening lr()ni the ritjht 
po.sition. 
Kig. 12. Photograph 10 shows bud on the left 
swelling. 



f-ijf. i.i. 



-Photograph Ho. The bud is half open, 
and the bud on the right is in the 
vertical position, read> for opening. 

Hig. 14. Photograph 150. ISoth flowers open. 

Fig. 15.— Phot ,>graph 220. Still further open. 



cannot be watched by the eye, and which last over a 
considerable period of time has, no doubt, often been 
thought of, but has not been put to much practical test. 
In fact I know that some years ago, two eminent pro- 
fessors of science visited one of the popular places of 
entertainment to watch a boxing match on the screen, 
with a view to obtaining hints for the use of the kine- 
matograph for scientific purposes. I did not hear that 
the experiment went any further. 

In the plant world there are many fascinating sub- 
jects possible. If photographs of a germinating seed are 
taken by the kinematograph at regular intervals during 
many days until the seed has germinated and sent up 
its seed leaves, the photographs can be thrown on 



ratus is too great for the use of amateurs, as, exclusive 
of the initial expenditure, each new film costs go marks = 
£^ los. I hope to explain in the following pages the 
method of working a smaller and less expensive appa- 
ratus, which is within the reach of the ordinary amateur 
photographer. 

The first plant selected for experiment was Sparniannia 
africana,''- a native of South Africa well known in our 
greenhouses. A photograph is given of the inflorescence 
of this plant (fig. ii), which gives some idea of its general 
appearance. It is a plant which belongs to the same 
order as the Lime Tree, and has many attractive features ; 



Annals of Botany, Vr>!. XVII.. No. LXVIII. Sept , 1903. 



Figy 



SparmaLnniac a-frica-na.. 

-10. Shows stages selected from the Kammatograph photographs in the opening of a bud. 




p.g. I. Watch the bud. 



Fg. 



I ig .1. 



fig. 4. 



Fig. .■;. 




Fig. 0. 



Fig. 



Fig. X. 



Fig. 9. 



Fig. 10. 



84 



KNOWLEDGE & SCIENTIFIC NEWS. 



May, 1904. 



the buds, which hang down round the stem, only open in 
sunli,t,'ht at a temperature of not less than ahont 60° F. 
26° C., the flowers shut up every night at varyin,t,' times 
according to their age, opening again each morning for 
several days, and each day the flower alters in appearance. 
This can be seen in the drawing — the buds are hanging 
round the stem — one flower is just opening; there are 
two older flowers and several in an upright position 
which have closed, and are about to form fruits. 
Then the stamens are sensitive, and when touched move 
away from the stigma. The way the flowers are arranged 
on the stem is also interesting ; the buds hang down at 
flrst, then move upwards during the night, and then bend 
again into the vertical position before openmg as in fig. i 
bud. There is a little joint or pulvinus on each flower stalk 
where the bend takes place ; when the fruit is ripe a layer 
of cork is formed at this joint and there the fruit is de- 



differs in size. It is capable of taking 350 photographs. 
When ready for use, the disc is put into the machine, 
which is light proof, and by means of a handle at the 
side can be rotated, so that every part of the plate 
is exposed before the small oblong opening in front 
of the lens and the photographs appear in a spiral 
on the disc. In ordinary kineniatograph work, the 
handle is rotated at a uniform speed and a series of snap- 
shots are produced, but for the work now required, it is 
necessary to take time exposures, as photographs must be 
taken at all times of the day and in all weathers ; a large 
number of photographs are only wanted when rapid 
movements, such as that made by the stamens when 
touched or when a bud is opening, are taking place. 

For miny parts of the day a photograph taken once 
every quarter of an hour is sufficient. 

The practical difficulties in this kind of photography 



Weather Plant lAbms prccatonus 













^, 




1 


\ 








^iiiiMiHiim fl 


-J'. ■■■• 








■'^4». 




"';-. 


%^iWI9||^ ■ 


• 


1 


*^ 



Fig-. 22. 



Fig. 23. 



Fig. 24. 



Fig. 22. — Photograpli. Position of leaves at 
2.18 p.m.. on Marcii 31, 1P04. 

Fig. 23. — Pliotograpli. Position of leaves at 
5.15 a.m., the whofe rachis is 
moving up, tiioiigti tlie leaves 
are not yet open. 




Fig. 24. Photograph. Position of leaves at 
10 a.m., April 1, 1904. 

Fig. 25.— Shows the night position. 



Fig. 25. 



tached. This plant seemed, therefore, a very suitable 
one for experiment. I aimed at photographing the in- 
florescence at intervals wliile young, so as not only to 
show the opening of the flowers, their closing at night, 
and the movements of the stamens, but also the develop- 
ment of the inflorescence from bud to fruit. I hoped in 
this way to show the progress of the plant during several 
months in a few minutes on the screen. 

My first experiments with a film kinematograph, 
though successful enough to encourage me to proceed, 
had many defects ; the machine was not constructed for 
this sort of work, and the maker was unable to help in 
adapting it. The celluloid film would not stand the 
constant damp of the greenhouse, and this was only one 
of the many difficulties encountered with this machine. 
My most successful experiments have been with the 
Kammatograph, in whicii the photographs are taken on a 
glass disc instead of a film. The disc, 12 inches in dia- 
meter (half of one is shown in fig. 16) is suspended in a 
metal ring; it is coated with a sensitive emulsion, just 
like any ordinary photographic plate, from which it only 



are rather overwhelming at first, but I have now over- 
come the principal ones, and think that anyone who 
cares to try the experiment for himself will find it 
fairly easy. The expense of each negative plate is 2s. 6d. 
and the positive is also 2S. 6d., so that the total cost of 
each completed kinematograph picture is 5s., plus the ex- 
pense of developing. If this is done professionally, each 
plate costs is. to develop, thus bringing the cost up to 
7s. The developing and printing are extremely simple 
compared with a film negative, as all the 350 photographs 
are developed and printed at the same time and in the 
same way as an ordinary plate ; this seems to me a great 
practical advantage. 

Two principal points must be considered : — 
I. — The apparatus must be quite rigid, as the slightest 
movement would spoil the whole result. Mr. Kamm has 
now devised a very satisfactory stand for this purpose. 

2. — Each photograph must be exposed uniformly, and, 
as they have to be taken at all times of day and night, 
this at first was one of the greatest difficulties. By the 
use of Wynne's actinometer, this difficu'ty was completely 



May, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



S5 




h 
< 

> 



z 






■,'' 1 





o 

D. 






a 
a 
n 



■= c: S 
i! " - . 

n 1> u 71 

4J i O — 

•= ,^ S u 
•^ o «.ti 

w c aj ^ 

« 7) 

_ O 

r, ~ 

^c x; 
o - 



o " = 



(/I 



0) 



t/: n ?• o 
^^ bti — 

■2i ^= = 

c3 '. B a> 

* S- * " 

•I --^ 

j: f £ a 

U L- CI) 

M V M I) 

2 N 2 ■= 

o . c '" 
£ o j: 
0. - a. „• 

. 00 . " 

- '. " .^ 

. "' . LL 
M M bi 

il ti. il = 



86 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



removed. I at first used 
night exposures ; but this 



r.ia,:;T.eb!u:ii 
was very 



laborious work. 
I now use an incandescent lamp fed by methylated 
spirits, but for those who are fortunate enough to 
have electricity an arc lamp is best of all. When once 
the right e.xposure is found all further difficulty in this 
direction is removed. No doubt the ideal method would 
be to ha\e a clockwork apparatus for turning the machine 
which at the same time turned on the light and exposed 
the plate, as Professor Pfefter has. 

The Sensitive Pla.r\t. — Mimosa seusitiva. 

This plant closes its leaves when touched, and also 
naturally shuts them up at night. The leaf is divided 
into two piniur, each divisi'^n bearing numerous leaf- 
lets. The best way to make them work is to light a 
match and put it under the end pair of leaflets at the 
tip of one of the pinna of the leaf. The first pair of 
leaflets then shut, then the second, and so on till the 

Climbing Plant {Mucuna nivca"\. 




Fig 29. 




Fig. 20. 



Fig. 28. 



Figs. 26 and 27.-Pliotographs. Show the tip of the stem turning round the support. 
Fig. 2S.-Photograph. Shows the same tip appearing on the other side of the support. 
Shows the tip applied closely to the support. 



Fig. 20. — Photograph. 



whole pinna is closed ; the same stimulus then closes the 
two leaflets next the stalk of the neighbouring /jwm,, and 
the leaflets close one after the other till the tip of the 
leaf is reached. Every leaf on the same branch follows 
suit, .\fter some time the leaf-stalk falls, another leaf 
closes m the same way, until the effect of the stimulus is 
at an end. These photographs are taken as quickly as 
possible consistent with giving the right exposure, and 
require a whole plate. 

A second plate shows the leaves reopening, taken at 
intervals of about five minutes: the exposures were con- 
tinued until the leaves shut into the sleep position for 
the night. 

The more common species, .1/. pudica, serve equally 
well lor experiment. 

The Weather ¥^\3.r\i.—Ahnts precahriiis. 
There has been much discussion about this plant lately 
as to whether it really predicts the weather to be expected 
in the future. I have a series of photographs extending 



over one complete day, whici. ......v. the regular day and 

night movements of the plant. The plant was kept in a 
glass case sheltered from wind and sun at a temperature 
not below 73° F. = 22-5° C. The plant was placed with 
the rachis (midrib) of its youngest leaf facing north. The 
photograph was begun at 11.30 a.m. on Thursday, March 
31, 1904, and continued until 10.30 p.m. It takes up the 
sleep position at 4.30 p.m. Then the photograph was 
begun again at 5 a.m. on .\pril i, while the leaves v.-ere 
still shut. As the sun rises the leaflets gradually open, 
and each leaf raises itself so quickly that one can watch 
the movements easily. 

The kinematograph seems to afford a means of defi- 
nitely settling this question. The photographs give an 
unbiassed record of the movements of the plant and the 
weather reports, barometrical and thermometrical read- 
ings, records of earthquakes, &c., can be provided by the 
various meteorological stations, so that if a re-investiga- 
tion is ever considered necessary after Professor Oliver's* 
exhaustive report on the subject the data 
could in this way be obtained. 

Climbing Plants. — This is a very fas- 
cinating subject for the Kammatograph. 
( )ne has to focus the support on which 
the plant is climbing and to keep 
the tip of the climbing stem in the held. 
.\s the plant grows in length the Kam- 
matograph has to be raised. In showing 
the photograph with the lantern a jerk 
will be noticed every time this is done, 
so if it can be arranged to alter the 
stand every morning one can see how 
much the plant has twined each day. 
Anyone who takes the trouble to photo- 
graph a climbing plant will be surprised 
at the very curious movements of the tip. 
The way in which it circumnutates, turn- 
ing to every point of the compass, then 
gives a twist when it comes into contact 
with its support, is very fascinating. 

The real difficulty with the climbing 
plant is that it grows and climbs just 
as much at night as it does in the day, 
so that if it is not photographed at night 
there is an interruption when projecting 
it with the lantern corresponding to the 
beginning of each new day. I am afraid 
a perfect photograph of a climbing stem 
will not be attained without clockwork 
apparatus, as the trouble involved of sitting 
up all night for at least a week would be too much to 
expect, even of the most ardent photographer. 

The plant illustrated is a Calcutta stem-climber, 
Muciina invca. It was photographed for a week from 
6.30 a.m. to 11.30 p.m. 

I hope in these few pages that I may have succeeded 
in interesting some of the readers of " Knowledge " in 
the work of making animated pictures of plants, and 
shall be only too glad if I can be of any use to anyone 
who wishes to try these experiments. The illustrations 
of such a subject are naturally disappointing, as they 
cannot appear animated, but if anyone will take the 
trouble to cut out the ten figures of the opening bud of 
Sparmannia africana (Figs, i-io) and paste each on a card 
or luggage label, and fasten them together closely at the 
'ower end, by letting each figure pass before the eye they 
appear animated and will give some rough idea of 



will 



what the plate will show when projected with a lantern. 
• Kew Bulletin, Jan , 1890. 



M.' 



AY, 190; 



KNOWLEDGE & SCIENTIFIC NEWS. 



The ** Canals" of Mars. 



A Reply to Mr. Story. 



Hv K. Walter Mainiiek, I'.K.A.S. 



Several correspondents having expressed a strong wish 
that I should give some reply to Mr. Story's letter on 
this subject, I will endeavour to do so ; not without 
reluctance, as the line which Mr. Story took seemed, in 
my opinion, hardly likely to advance our knowledge. 

If I may briefly summarise Mr. Story's objections 
to the paper communicated by Mr. Evans and myself 
to the Royal Astronomical Society last June, they 
come under three heads. He objects to me as the 
author, to the methods employed, and to the deductions 
drawn. 

The first objection is of course a somewhat delicate one 
for me to handle. It deals rather with the personal than 
with the scientific, and I have no inclination to fill the 
columns of Knowledge with detailed evidence of my 
claim to be considered an " expert " on the subject of 
Mars. Let it suffice that as long ago as 1877, I had 
made a thorough study of the planet, using the fine 
12^-inch Merz refractor of Greenwich Observatory. In 
1892 and 1S94 I also used the 2S-inch Grubb refractor — 
certainly one of the most perfect objectives in existence. 
I give two or three examples of my earlier drawings, from 




Fig. I. 



-Drawings of .Mars made witli the I2,=incii Refractor of 
tile Royal Observatory, (ireenwicii. 



H, M. 

I. 1877 September 29th 10 10 
3. 1879 November 5th.. 13 5 



It. M. 

J877 September 241I1 11 43 
lf5Sj January yth 12 2 



which it will be seen that I had recorded some of the 
markings now familiar to us as " canals " and " oases," 
even before Schiaparelli had published his results, and 
quite a number before they had been generally recognised 
by observers. 

So much for the person, next for the methods. Mr. 
Lowell and Mr. Story both appear to object to the 



employment of terrestrial experiments to elucidate plane- 
tary appearances. Mr. Lowell's opinion to tiiis effect 
may be found in his letter published in the " Observa- 
tory " for January, 11)04, p. .[g : '• Permit mc, in con- 
clusion, to point out to you . . . that the only evidence 
germane to the matter is to be got from astronomical 
observations directed to that end." But as Mr. Story 
points out, Mr. Lowell himself has set on foot terrestrial 
experiments for the express purpose of drawing infer- 
ences with respect to his observations of Mars, and Mr. 
Story approves of his so doing. Kliminating what is 
common to the two cases, the one of which meets with 
Mr. Story's approval, and the other with his disapproval, 
the only residuals are Mr. Lowell on the one hand and 
myself on the other, and the statement is reduced to the 
simple proposition that he approves of Mr. Lowell and 
disapproves of me, irrespective of our actions. In other 
words, his second objection is but a more diffuse way of 
restating his first. 

But to take the matter seriously, let us see prt;cisely 
what is the point where Mr. Lowell's \'iews and my own 
diverge. It is not in the chief markings of Mars. Mr. 
Lowell sees and draws these substantially as I saw and 
drewtheni in 1X77, and as Beer and Miidler drew them in 
1830. It IS not in respect to the appearance of the 
" canals " ; 1 observed and drew " canals " as far back as 
1S77, and though of course Mr. Lowell has seen and 
drawn far nion; " canals " than I have, those that I saw 
were substantially of the same character as his ; and in 
the discussion of this cpiestion 1 have been most careful, 
both in writing and speaking, always to point out that 1 
was not throwing doubt eithtrr on the fidelity or the skill 
of any of the observers of Mars. Mr. Evans and myself 
wrote : •' It would not be in the least correct to say that 
the numerous observers who have drawn 'canals' on 
Mars during the last twenty-five years, have drawn what 
they did not see. On the contrary, they have drawn, 
and drawn truthfully, that which they saw." (" Monthly 
Notices" \'ol. LXIIL, p. 499.) Nor have I ever 
asserted or assumed " that the canals are seen as very 
faint lines, so faint that their existence is doubtful even 
to experienced observers." 1 know the reverse by actual 
experience. 

We agree on a third point. Mr. Lowell is absolutely 
convinced, and in this 1 am quite at one with him, that it 
is not possible that an actual network so geometrical 
as that which he represents can be the result nf 
purely physical causes. Mr. Story has no doubt seen 
the very fascinating book which Mr. Lowell published 
on "Mars" in November, 1895, and has read the pages 
148-154. 

After this we differ. Mr. Lov/ell attributes this con- 
fessedly utterly unnatural network to the handiwork 
of intelligent beings who have woven over their 
planet these "grotesijue polygons" to use Schiaparelli's 
expression. 

This, be it nijted, is inference, not observation ; and an 
inference which demands the assumption that, were i\Iars 
brought much nearer to us, or our power of seeing greatly 
improved, these grotesque polygons would still persist, 
and would never resolve themselves under better seeing 
into markings which we could reasonably ascribed to the 
unaided processes of Nature. 

My inference is different; the unnaturalness may be 
due to the imperfection of our seeing. I rely on well- 
known facts respecting the theory of vision and the 
structure of the eye, and the eye is our necessary instru- 
ment for observation. We have no right to resort to the 
unknown and the artificial, before we have exhausted 



88 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



the known and natural methods of explaining a pheno- 
menon. My inference is one based on the observed 
effects of known causes; Mr. Lowell's inference is an ex- 
cursion into fairyland. 

We know that the smallest single dark marking on a 
bright ground which can be seen by an observer of per- 
fect sight, without optical assistance, must have a 
diameter of at least 34 seconds of arc. This diameter 
depends upon the size of the rods and cones of the eye 
which receive the visual impression, and compose the 
sensitive screen. It is therefore an inevitable limit. .\s 
this diameter is necessary for the object to be merely 
perceived, or, in other words, to create any sensation at 
at all, it follows that in order that the actual shape of the 
object may be recognised, its diameter must consider- 
ably exceed this limit, otherwise it will be seen as a truly 
circular dot, whatever its actual shape. 

This is the case for small isolated markings just 
within tlie limit of visibility. The case is different for 
extremely elongated markings ; the increased length of 
a marking will compensate for diminished breadth up to 
a certain limit, but not beyond it. For a Ime of indefi- 
nite length the limit of breadth approaches two seconds of 
arc. A line of a breadth below one second of arc is 
invisible, no matter what its length ; but it must have a 
breadth many times this amount before it can be seen as 
anything else than a mere line — before irregularities in 
shape and breadth can make themselves apparent. 

In naked-eye vision, therefore, there is a considerable 
range within which small objects, whatever their true 
shape or nature, can only be seen as dots or as lines. 
The result is that these two forms are certain to come 
in evidence whenever we are dealing with objects too 
minute to be fully and properly defined. 

The problem becomes more complicated when we are 
using optical assistance, as there is a limit of definition 
belonging to the telescope as well as to the eye. But 
the principle remains the same ; the result of adding the 
limitation of the telescope to the limitation of the eye 
being that the actual magnification of the telescope can 
never be nearly as effective as it is nominally. A power 
of 300 on the best telescope in existence, and under the 
best atmospheric conditions, would never show the 
features ot the moon as distinctly as they would be seen 
if the moon were brought 300 times as near. 

Mr. Story and Mr. Lowell both object that terrestrial 
(or, as they are more usually called, " laboratory ") expe- 
riments are altogether beside the mark when applied to 
the interpretation of astronomical observations. The 
contention is a ridiculous one, and if logically applied 
would render it impossible to determine the instrumental 
errors of a transit circle by the use of meridian marks, 
collimators, or mercury trough, or the personal equation 
of an observer, except by actual stellar observation. 
They would also foibid us to identify the lines of solar 
or stellar spectra by comparison with those of any terres- 
trial element. 

Hut since it is contended that Mars alone can give us 
valid information on the subject, to Mars let us refer. 
If we turn to the drawings made by Beer and Miidler in 
1830, two small objects exceedingly like one another 
appear repeatedly. These are two dark circular spots, 
the one isolated, the other at the end of a gently curved 
line. Both recall the "oases" which figure so largely 
in many of Mr. Lowell's drawings, and the curved line 
at the termination of which one of the spots appears, is 
not unlike the representation which has been given of 
several of the " canals." There can be no doubt that in 
the year 1830 no better drawings of Mars had appeared 
than those to which 1 have referred, and that in 



representing these two spots as truly circular Beer and 
Madler portrayed the planet as they best saw it. The 
one marking we call to-day the Lacus Solis, the other the 
Siinis Siihifus, and we can trace the gradual growth of our 
knowledge of both markings from 1830 up to the present 
time. The accompanying sketches of the same region 



7^ 


r 


2. 


^- 


'/^ 


^ * 



Fig. 2. — Sinus 5aba;us and Lacus Solis. 



Sinus Sab.-eus 



Lacus Solis 



Beer and Miidler i»30. 
Lockyer . . 1862. 
SchiapareMi . . 1890. 
Beer and Miidler 1S31. 
Lockyer .. 1S62. 
SchiaparcUi .. i8go. 



by Lockyer, in 1862, and by Schiaparelli, in 1890, illus- 
trate well how the character of the markings revealed 
themselves with increased telescopic power and experi- 
ence in the observer. 

•' At first it seemed a little speck 
And then it seemed a mist, 
It mo\ ed and moved and tooli at last 
A certain shape I wist. 

A speclv, a mist, a shape." 

If Beer and Madler, in 1830, had argued that the precise 
circularity of these two spots, as they appeared to them, 
was proof that they were artificial in origin, would they 
have been correct? Would not the answer have been 
valid that a spot too" small to be defined must appear 
circular, and that, therefore, the apparent circularity pro- 
bably covered detail of an altogether different form ? 
We know that it would. Yet it is that same argument 
in a far stronger form against which Mr. Lowell and 
Mr. Story are contending to-day. Beer and Madler only 
drew two of these spots ; Lowell shows over sixty. 
Beer and Madler's two spots seemed to them precisely 
alike; how utterly different those two spots appear to us 
to-day the diagram may serve imperfectly to indicate. 
Mr. Lowell's sixty or more " oases," with one or two 
exceptions, appear all of the same character. Will any- 
one dream that if the next seventy years brings telescopic 
development equal to that shown in the last seventy, the 
present uniformity of Lowell's "oases" will persist, any 
more than the likeness of the two spots observed by Beer 
and Madler? We need not even wait for the seventy 
years. Up to the present moment I have carefully 
avoided anything like criticism of the drawings of any 
observer of Mars. I have repeatedly stated that I ac- 
cepted them as being both faithful and skillul representa- 
tions of what the observers saw. Ijut it is necessary 
here to point out that the extreme simplicity of type of 



May, 1904.] 



KNOWLEDGE c<t SCIENTIFIC NEWS. 



89 



both "canals" and "oa<:es," as sliown by Mr. Lowell, is 
not conriniied by the best obser\ers. In tiie last number 
of " Kniiwi.epgk " Mr. Denning writes (p. 67) : " There 
are really many distinctions in the canal -like markings ; 
some of them are (juite broad and ditTused shadings, 
while others are narrow, delicate lines." The Rev. 
T. E. Phillips has recently insisted strongly (" Monthly 
Notices," \'ol. LXI\'., p. 40) on the same fact, and 1 
could increase the testimony indefinitely. There can be 
no doubt that the best observers not merely agree in 
stating that the "canals" differvery widely in their charac- 
teristics, but they also agree closely in the characteristics 
they assign to special "canals." With regard to I-owell's 
observations 1 can, of course, speak only with reference 
to those which he has published, but speaking with re- 
ference to these there can be no doubt that he fails to 
e-xhibit that wide variation in character between cer- 
tain "canals" upon which these and other leading 
observers are fully agreed. This seems to me clear 
proof (so far as his published drawings go) not of superior 
conditions and skill -on Mr. Lowell's part, but of 
a most marked inferiority in one respect or the 
other. Whether it be the location of his observatory 
that is at fault, or the definition of his telescope, or his 
own personal skill in observation, or most probable of all, 
in delineation, the fact remains that- -despite the multi- 
plicity of his observations and the perseverance, which 
cannot be too highly praised and too fully recognised, 
with which he has observed Mars in season and out of 
season — he has failed to record difTerences apparent to a 
consensus of other first-rate observers. Especially he 
has failed to recognise what Denning and Schiaparelli 
had recognised as early as 1884, that many of the 
" canals " were very far from being straight lines of 
uniform breadth and darkness, but showed evident 
gradations in tone, and irregularities occasioning breaks 
and condensations here and there. Of all the thousands 
of drawings of Mars which I have examined, those that 
most perfectly corresponded to Mr. Lowell's were the 
work of a young novice and were made in by no means 
an ideal station, using a small home-made telescope. 

It is made an argument in favour of the actuality of the 
" canals " that they have been seen with such distinct- 
ness, or with such frequency. The argument is based 
upon a very complete ignorance of the appearance of the 
fictitious "canals" observed in the experiments made by 
Mr. Evans and myself. I have myself been completely 
taken in by a little drawing on which the Syrtis Major 
and Sinus Sabseus were shown. As I looked at it by 
far the most insistent feature was a straight, narrow, 
intensely black line corresponding to the Phison. Yet 
that astonishingly vivid impression was really due to the 
integration of two or three feeble lines, irregular, broken, 
and serpentine curves, and half a dozen utterly invisible 
dots. If I had looked at that drawing a thousand times, 
or if a thousand other observers had examined it under 
the same conditions as to distance, they could only have 
seen what I saw — a dark, straight line, as sharp as if cut 
by a graving tool. 

The change in the distinctness of the "canals," con- 
sequent on the progress of the Martian seasons, was no 
discovery of Lowell's; the fact was realised by Schiapar- 
elli very early in his observations. But so far from 
rendering it more probable that the "canals" indicate 
artificial water-ways, it affords a most serious argument 
against their having that character. For water cannot 
flow uphill, yet the water from the melting polar snow, 
according to Lowell, must flow upwards to reach the 
equator. If, with Lowell, we consider the dark markings 
on Mars to be vegetation rather than water, they would 



change in appearance with the seasons whether they were 
of natural origin and irregular shape, or were artificial and 
symmetrical; and Mr. Lowell's S500 ohser\ati()ns do not 
increase the probability of his theory more than 85 or Hh 
would do. .\ " canal " or an " oasis," if seen only as a 
straight line or a circular dot, that is lo say, if seen only 
in the simplest possible form, affords no proof that the 
precise form under which it appears has any actuality. 
It is only when the object begins to show detail that we 
are sure that we are beginning to sec it as it is. And one 
of the most convincing testimonies that Mr. ICvans and 
myself have been following the right line has been shown 
by the attitude which the most experienced observers of 
Mars have adopted towards our intjuiry. They have 
claimed, as Mr. Denning did in last month's " Know- 
i.EDc.E," that certain "canals" are undoubtedly real, for 
they have been resolved or partially resolved into minuter 
details, being "composed of small, irregular condensa- 
tions." Others they have admitted may be "canals" 
only in appearance, being actually either " the edges of 
half-tone districts or the summation of very minute 
details." In both the claim and the admission they are 
in perfect accord with the position held by Mr. Evans 
and myself. On the other hand, Antoniadi, Bariiard, 
Denning, Molesworth, Stanley Williams, have all held 
themselves aloof from the bizarre delineations and yet 
more bizarre theories which Lowell has promulgated. 
Most striking of all, Mr. W. H. Pickering, who preceded 
Mr. Lowell in his argument that the water supply in 
Mars is restricted, and in the recognition of the system of 
" oases," who further has had the opportunity of observ- 
ing with Mr. Lowell's telescope and in the climate of 
Arizona, has not only frankly accepted our position, but 
has supported it by direct photographic proof. Mars, 
unfortunately, does not lend itself to photography, but 
the Moon does; and Mr. Pickering has found confirma- 
tion of our experiments as to the building up of straight- 
line systems from imperfectly seen details by comparing 
his drawings of certain lunar formations with actual 
photographs. 



Stimulus and Sensation 



By J. Reynolds Green, Sc.D., F.R.S. 



If we contemplate the enormous variety of form and 
structure which we find to exist among plants, and en- 
deavour to study the reasons which we can readily trace 
for the diversity in these respects, the conviction is 
forced upon us that the story which is hidden there is 
one of stress and struggle, the result being a correspon- 
dence between the plant and its environment, so that 
the former can take advantage of all that is offered to 
it by the latter, and can resist successfully such dele- 
terious influences as are inevitable from its situation. 
Hence different environment entails different structure. 
Moreover, as the en\ironment is continually changing 
in some respect or other, the organism is continually 
involved in the struggle to adjust itself to the alterations 
thus besetting it. in the absence of power to maintain 
satisfactory relations, the plant becomes unhealthy, and 
after a time it perishes. Health, indeed, is but the ex- 
pression of a satisfactory equilibrium gained and main- 
tained between the plant and its surroundings. 



go 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



As we cannot deny the extreme probability, perhaps 
we may say the certainty, that all plants now living have 
been descended from some primitive form, we can find in 
the history of different races the enormous effects which 
long-continued struggle for successful adaptation to a 
changing environment can achieve. The effect of change 
upon a single individual may be, indeed, must be, slight ; 
but long-continued influence upon long series of descen- 
dants brings about a marked ctunulative effect, and 
though we see little change in a generation, we are obliged 
to admit relatively enormous modification in the course 
of time. But though we can see little alteration in the 
individual, we may argue backwards and realise that no 
great change could occur in a race except by modifications 
of successive indi\'iduals of it. We must, therefore, look 
minutely to the individual to see what the properties are 
which in long years can effect such modifications of both 
form and structure as we find. 

We have then to study what we may call the adapta- 
tion of the organism to its environment. At the outset, 
we must admit that such adaptation can take place only in 
two ways. Possibly, all plants whose constitutions are 
not in harmony with the changed conditions will perish, 
leaving more fortunate ones to carry on the race. 
This postulates that the plants of any particular genera- 
tion are themselves varying slightly in their physiological 
properties. Possibly, on the other hand, the individual 
organism is possessed of a power of appreciating changes 
in its surroundings and of modifying its own behaviour 
accordingly. It may well be that both these hypotheses 
are to a certain extent true, and that they are co-operating 
to bring about the results we see. 

There are strong grounds for accepting the latter of the 
two views as playing a very prominent part in the 
changes of the past. We can see certain phenomena 
occurring under our own eyes which are capable of in- 
terpretation in the way suggested, which, indeed, are 
inconsistent with any other hypothesis. A plant acted 
upon by a certain definite external influence modifies its 
way of behaviour in an equally definite manner. It is 
difficult to deny to the plant the power of perceiving the 
influence brought to bear upon it. The effect of the in- 
fluence is technically called a stimulus, and the percep- 
tion of a stimulus by the plant is known as a soisatioii. 
We have two factors then to consider, one external, the 
other internal, to the plant. 

A more complicated question arises here. Is the percep- 
tion of a stimulus, is a sensation, to be interpreted as 
implying any kind o{ consciousness ? We have a stimulus, 
we have a response. What can we say of the interpreta- 
tion of the one by the plant which makes it bring about 
the other ? The problem is very difficult to speak with con- 
fidence upon in the present state of knowledge. The 
human mind shrinks at once from taking the affirmative 
view. No doubt, in the higher sense in which we interpret 
the word, no consciousness can have part in a vegetable 
organism, for this sense implies ihuus^ht. It is difficult 
to suggest that a purposeful response implies any kind of 
volition. These operations are the immediate functions 
of the well-organised and most highly-developed nervous 
centres of the highest animals. But certain facts can be 
adduced which, at any rate, hint at the existence of such 
a limited consciousness as implies an appreciation of the 
nature of the surroundings. 

To discuss this question at any lenj^th would, however, 
take us beyond the purpose of this article. We must 
confine ourselves to the question of stimulus and sensation 
as far as we can see them both at work in the course of 
ordinary vegetable life, leaving the full interpreta- 



tion of the relation between them to be set aside for the 
present. 

The nature of a stimulus first concerns us. We may 
take it for granted that there may exist for every plant, 
at any rate theoretically, a condition of adjustment when 
it is in absolute harmony with its environment — when 
temperature, illumination, moisture, rest, and whatever 
else affects it, are perfectly as the organism wants them, 
and when consequently its life is lieing regulated to the 
utmost advantage. Such a condition can be only 
momentary in any case, for the surroundings are in a 
constant state of change in many of these particulars, and 
the living substance of the plant is also exhibiting con- 
tinual motility. For the maintenance of health, or even 
of life, it is essential that variations in the one shall be 
adequately responded to by variations in the other. The 
impossibility of securing indefinitely such a continual 
adjustment of relations is the cause of the cessation of 
life. 

Such an alteration of the environment constitutes a 
stimulus. It may affect the plant in a hundred ways, 
causing various methods of response, and various degrees 
of intensity of response. 

There are, however, other factors influencing its 
life which are not so easily realised by observation. 
Changes may arise in the condition of the living sub- 
stance of the plant, set up perhaps by disturbances in its 
interior. The normal cause of chemical change associated 
with the nutritive processes may undergo a marked change 
in consequence of an alteration of the distribution or the 
direction of the stream of food in the plant's interior. 
Injury to the body of the plant may involve a re-distribu- 
tion of energy or of material within it, which may have 
far-reaching effects upon the course of the vital processes. 
Variations in the supply of food, which may range be- 
tween absolute starvation and over-engorgement, may 
produce very great changes not only in the outer life of 
the plant, but in the substances it produces in the course 
of its nutritive processes, and in the energy which it 
liberates. An insufficient supply of oxygen may provoke 
an almost entirely new series of chemical changes in 
connection with the production of such energy. These 
various factors and many others which might be quoted 
are to. be regarded as stimuli, some of them internal no 
doubt, but all equally real and equally well appreciated 
by the plant as the more obvious external ones just de- 
scribed. Even more obscure stimulations may arise 
from chemical changes in the living substance itself, 
leading to a series of responses which, as they do not 
appear immediately related to \isible stimuli, are often 
called automatic. 

To appreciate more fully the part played by stimulation 
in the life of a plant, we may briefly consider a few of its 
more obvious forms. Consider the lateral incidence of 
light upon a growing seedling or young plant. If the 
latter is placed so that one side of its stem is more bril- 
liantly illuminated than the opposite, a curvature soon 
appears in the part that is actively growing. This is of 
such a nature and takes place to such an extent as to 
cause the axis of the plant to take up a position in which 
it is parallel to the direction of the incident rays. It 
manifests itself in some cases very slowly, in others com- 
paratively rapidly. This response to the stimulus of un- 
equal illumination on its two sides is not confined to the 
stems of seedlings, but may be seen to a greater or less 
degree in parts of many adult plants. It is a matter of 
common observation that geraniums grown in a windoAv 
all bend their steins and petioles towards the illuminated 
side. 



May, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



91 



In other cases the same stimulus may be responded to 
in quite a diflerent manner. When certain younf^ roots 
are exposed to it they curve so as to place themselves in 
the same position with regard to the incident rays, but 
with their growing apices in the opposite direction. 
\"arious tendrils, peduncles, and other organs respond in 
a similar manner. Leaves tend to place themselves 
across the incident rays. 

Among the obvious difficulties which beset the course 
of a root in making its way through the soil is that of 
impinging more or less directly upon some particle which 
it is unable to displace. In practice it is nearly always 
found to be able to grow past such an obstacle. The 
situation affords us another example of stimulus appre- 
ciated and responded to. Contact with the apical portion 
of the young root causes an immediate departure from 
the straight line of growth. The behaviour of the organ 
can be studied on a germinating bean with great readi- 
ness. If such a structure be kept in moist sawdust till 
the young root emerges, then be transferred to a moist 
chamber and suspended therein, a small piece of hard 
substance, such as card-board, can be attached by 
a little cement to the side of the lip. The root at once 
begins to curve away from the side thus touched, and if 
the stim.ulation is maintained for some time the resulting 
growth will cause the root to grow into a loop. If a 
tendril of Passi flora gracilis have a small loop of thread 
laid upon a certain portion of it, it will curve at once and 
in about two minutes will assume the form of a helix. 
Other tendrils behave in a similar way on coming into 
contact with different hard supports, though the rapidity 
of their response varies considerably. 

The nature of the response must, however, be con- 
sidered before we can associate it in any co-ordinated 
fashion with the stimulus. Such co-ordination between 
the two must be put in evidence if we may fairly deduce 
such an appreciation as we can call sensation. 

The first thing that strikes an observer is the evident 
purposeful character of the response. The position 
assumed in relation to the incidence of the lateral light is 
that which will ensure an equal illumination of the sur- 
faces of all the leaves. These spread out at approxi- 
mately equal angles with the stem in all its sides, and 
hence w^hen the stem is parallel to the light source the 
greatest amount of sunlight falls upon the green surfaces 
of the plant, where the work of forming sugar under the 
influence of such light is taking place. The opposite 
effect produced upon roots is calculated to press them 
closely into the soil, where their absorbing hairs can have 
free play. The curvature of the tendril assists it to 
secure a holding for the plant, so that its weak stem 
escapes being trodden down and its leaves are enabled to 
reach light and air. 

A less obvious consideration is afforded by the fact 
that the parts of the plant receiving the stimuli are in 
cases strictly localised. The receptive part of a root is 
just behind its apex ; that of a young seedling stem is in 
about the same position. Not only is this part localised, 
but it is situated in quite a different part from that which 
effects the movem.ent. The latter is caused by grov.-th 
some half-inch or so nearer the base, at a part which is 
quite insensible to stimulation. 

Another consideration which bears upon the question 
is that an extremely small stimulus is able to bring about 
a very considerable effect, and that there is no simple 
ratio between the intensity of the stimulus and the extent 
of the response. An instance of this is afforded by the 
behaviour of the tendril of Passiflora already described. 

We can, therefore, associate stimulus and sensation and 
point to the response of the plant as evidence of both. 



Saturn. 



.At the beginning of May Saturn rises 2i hours before the 
sun .ind telescopic observation may be renewed, tliouf,'h the 
planet will scarcely be far enoiif^h west of the solar orb to be 
presented under very satisfactory conditions. The ensuing 
apparition of this attractive object is likely to prove of great 
interest. His southern declination will he 3' less than it was 
last year and this ought to bring about an improvement in the 
definition. 

In the summer of igoj Saturn displayed the evidences of 
considerable activity in a niunber of bright and dark spots, of 
irregular form, distrihntcd in about N. lat. 35' along the polar 
side ofthe northern equatorial beU (" Knowleoge," Dec. iy03). 
In June, July, and Augnst these markings were frequently 
seen, though but few observers appear to have retained them 
in view during the autumn mouths. The rotation period of 
the chief spot or spots was variously determined as follows :— 
Observer or Period. Days of We«<5rence. -^ 

Authority. li. 111. Observation. ,>> . v 

K.Graff .. 10 39 o' 3 , ^5«. >^''* 3S830t V^ V 

J. C. Sola .. 1038-4 3f-. ^5£.. JVac/i. 389ij<\\ T 

" - ■ 10 380 18' .-• ■ -Sj V V^ 

10 38-8 ' 40 ^5<.j;aj(ii\547. ^,v 



P. Fauth 
'E. E. Barnard 

L. Brenner . . 



10 38-0 
h. in. 



H. W. Wilson 10 38 4iS|a\>'7S!' ^'^.?^^^'; '°^ 



i^ 



•(;. W. Hough.. 
•G.W. Hough.. 
tW. F. Denning 



10 38 27' 
10 38 30'5 
10 37 56 4 



53 

24^' 

129 



l^ilIihNot. Dec, 1903. 
Monthly Not. Dec, 1903 
Monthly Not. Jan., 1904. 



* In these cases the identifications were uncertain and the resulting periods 
probably excessive. 

f Mean value derived from observations of i8 spots. 

As soon as Saturn can be successfully examined it will be 
important to ascertain whether the markings continue percep- 
tible. Possiblv, at the present time, the northern hemisphere 
shows nothing'more than the beautifully symmetrical belts and 
zones which usually stripe the disc. The material of the 
differently tinted irregularities seen in 1903, which proliably 
resulted from extensive eruptions affecting the atmospheric 
scenerv, may have amalgamated with the ordinary bands of 
the planet and quite lost their distinctive outhnes. And the 
region affected mav remain (juiescent for a time to be again 
disturbed by further outbreaks in the near future. The phe- 
nomena occurring on Saturn are, no doubt, very similar to 
those visiblv taking place on Jupiter, and observation has 
taught us that on the latter planet one disturbance scarcely 
subsides before another forces itself into prominence. The 
spots common to certain latitudes of Jupiter possess some 
physical resemblances, and are characterised generally (though 
not invariablv) by nearlv identical rates of motion, according 
to the longitudinal current in which they are placed. The 
same thing is likely to be displayed on Saturn, and the few 
following years may be expected to furnish useful evidence on 
this point. 

The spots on Saturn remained fairly conspicuous objects m 
December, 1903, and observers will probably redetect them 
during the present spring. If so, it will be desirable to obtain as 
many transits as possil)le, 90 that the individual objects may 
be satisfactorily identified and their periods of rotation rede- 
termined. ,•,.,, r ,. 

The markings referred to certainly exhibited some of the 
vagaries which occasionally affect the features on Jupiter, for 
the rate of their motion underwent a decided acceleration at 
the close of the apparition. Several of the principal objects 
which, during the summer, gave a period of lohrs. 38 ruin. 3 sec. 
conformed witli a shorter period of 10 hrs. 37 min. 50 sec. 
during the latter part of the autumn. 

In regard to Saturn, the year 1903 will be remembered as 
one of considerable historic interest, for the rotation of the north 
temperate region was found to be 235 minutes greater than that 
derived by Professor Hall from his equatorial spot of 1876, 
and the fact rendered conclusive that this planet, like Jupiter, 
displays atmospheric spots affected by large proper motions. 

Mr. Crommelin's " Ephemeris for Physical Observations of 
Saturn. 1903-4" {Monthly Notices, December, 1903) will be 
found extremely useful in the further study of this interesting 
object. w. F. Den.ning. 



92 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



The Do\ible 

Stereoscopic Projection 

of the Eight-Cell. 

By G. H. Bryan. Prof. Sc. D., F.R.S. 



In connection witli Mr. Benham's paper on " The Super- 
Solid," it will be noticed that the diagrams of pairs of 
connected cubes, even when seen through a stereoscope, 
fail to convey the impression of being the projections of 
a regular figure. 

A much better idea of the regular character of the 
" super-cube " or "eight-cell," as it is called by most 
writers, and of its connection with four-dimensional 
space can be acquired by choosing the jilane of projection 
in such a way as to give the dia^jram a more symmet- 
rical form, and by using two different stereoscopic pro- 
jections instead of one. 



space containing the first, second and third dimension, 
the other view^ represents the aspect of the same " eight- 
cell " projected in a space containing the first, second 
and fourth dimension. 

Either of the two aspects shows a solid figure, which 
is symmetrical but not perfectly regular. It is not difficult, 
however, to convince oneself that the four-dimensional 
figure of which the two aspects are simultaneous projec- 
tions is regular. 

In regard to the fact that in either view two of the 
vertices (not the same two) appear inside the solid pro- 
jection, a comparison of the two aspects will show that 
they are not really inside, but only look so owing to the 
direction of projection. This property is exactly analo- 
gous to the fact that if we draw the trace of a cube by 
projection on a plane, the projections of two of the ver- 
tices will be inside the polygon formed by the projec- 
tions of the remaining vertices. It is only when the 
cube is viewed as a solid, or studied by means of its pro- 
jections on different planes, that we become aware that all 
the vertices he on the boundary of the cube. 

-A. complete account of the regular figures possible in 






In the anne.xed series of diagrams the central figure 
represents a symmetrical plane projection of the " eight- 
cell." It is not the only projection which is symmetrical, 
but it is a convenient one in which the edges and sides 
are well separated, and are nowhere near overlapping in- 
conveniently. 

When this figure and the figure to :he left of it are 
viewed together through a stereoscope, the fines will 
stand out in relief, giving the impression of forming a 
solid figure in w'hich the point H is nearest the observer, 
and K is furthest always. The points C, P appear to h& inside 
the solid, and to be in the straight line joining E and N. 

Now let the central and the right hand figure be 
brought into view in the stereoscope, and it will be ob- 
served that the whole aspect of the figure has altered. 
This time P is at the front of the figure and C is at the 
back, while the points H and K which were previously 
the nearest and furthest points appear to be inside the 
figure in the straight line joining Q and B. 

As the same central figure is used in both cases, the traces 
of the two stereoscopic solids on the plane of the paper 
are, to all intents and purposes, the same. If, as assumed 
they both represent ditt'erent aspects of the same figure 
the distances of the different points from the plane of the 
paper in the first place must be entirely independent of 
the distances from the plane of the paper in the second 
case. These distances therefore correspond to different dimen- 
sions of space. 

In fact, if the first stereoscopic view represents the 
projection of a four-dimensional " eight-cell " in a solid 



four-dimensional space, corresponding to the five regular 
solids enumerated in our text books of elementary solid 
geometry, is given by Mr. S. L. Van Oss in the Trans- 
actions of the Amsterdam Academy for 1899. The 
largest number of faces a regular solid can have is 20, 
the figure being known as an icosahedron, but in four- 
dimension space, the maximum number of boundaries is 
600, and the projections of the "600 cell" shown in Mr. 
Van Oss's diagrams are very beautiful and symmetrical. 
An interesting variation of the experiments described 
in this paper may be made by cutting out the two 
extreme figures and placing them simultaneously in the 
stereoscope, then inverting one of them and again placing 
in the stereoscope. In this manner two other aspects of 
the eight-cell w^ill be seen. The scale of stereoscopic 
relief will, howe\er, be different to what it was in the 
previous observations, but this will not much matter. 

N-rays and Smell. 

Thh controversv concerning the objective reality of the 
N-rays suggests "that to the proverb concerning the difficulties 
of accounting for taste, we shall have to add other maxims 
about the difficulties of accounting for sight and smell. On 
the oue hand. M. Blondlot, Professor Charpentier, and M. 
Edouard Meyer continue in their respective spheres of investi- 
gation to add new facts each week— by means of papers read 
before the Academie des Sciences — to the common knowledge 
of the N-rays. On the other hand, Professor J. G. McKendrick 
and Walter Colquhoun, as well as other observers in Great 



May, 1904.] 



KNOWLEDGE & SCIEXTIEIC NEWS. 



93 



Britain, have failed to find any trace of the rays as ol)jecti\ c 
realities ; Professor C. C. Shcnolc has criticised, in a way which 
demands an answer, M. Blondlot's experimental methods and 
his alleged measurement of the N -ray's wave length ; and Herr 
O. Lummer has suggested, in a paper read before the German 
Physical Society, that the observed phenomena are due to pro- 
cesses in the retina of the eye (•• the contest between the rods 
and cones of the retina "). Meanwhile, the French observers 
go on undismayed by the stain of criticism and objection, and 
in Cosmos (April 2) Professor A. Charpentier gives the result 
of his observations on the connection between X-rays and the 
sense of smell. The N-rays, he observes, exercise a very dis- 
tinct action on the olfactory sense. It can be shown if the 
nose is approached during the action of smelling by a body 
capable of producing N-rays, such as a piece of tempered steel 
or the closed fist, that the sensation of smell is increased. The 
experiment must be made with all necessary precautions, in 
still air, very slowly, with gentle and regular breathing, the 
odorous substance being maintained at a fixed distance nearly 
approaching to the extreme limit at which the olfactory organs 
can perceive it. The source of N-rays can either stimulate 
the sense of smell when the limit of perception is almost 
reached, or increase its intensity where it is already in exist- 
ence. In both cases, the action is perceptible. It takes place 
when the source of the rays is approached to the root of " the 
nose or the base of the nostrils." If the mass of muscles in 
the thumb are placed against the nose, the slightest contrac- 
tion of these muscles produces the effect already mentioned. 
Essence of cassia was the odorous substance usually made use 
of by Professor Charpentier, but the same results have been 
obtained by him from very different scents — essence of 
lavender, thyme, cloves, mint, camphor, ether, iodoforme, 
ammonia, and acetic acid among them. The N-ray action 
penetrates thin sheets of aluminium, and it is useful in order 
to eUminate the currents of air produced, in spite of all pre- 
cautions, by displacing the source of the rays, to place a large 
sheet of this metal against the outside of the nose, and to con- 
duct the experiment on the other side of it. 

N-rays can, moreover, influence the olfactory sense when 
thev are made to act at certain points on nerve centres if, for 
instance, the substance, which is the source of the N-rays, is 
placed near the middle of the forehead immediately above the 
place where the eyebrows meet. The effect is especially 
striking when the source of the rays is placed on the summit 
of the cranium a little in front of the place of union of the 
frontal and the two parietal bones. 

This effect of N-rays is not confined exclusively to the 
organs of perception. The scent is increased to some extent 
when the radiating source is put near the flask containing the 
odorous substance at too great a distance from the nose to 
influence it directly. Professor Charpentier continues: "In 
the same way I have observed that the substances thus 
mentioned distinctly emit N-rays which traverse cork, and alu- 
minium, but are stopped to a great extent by lead, and can 
give rise, like the other sources, to secondary radiations. As 
for the action of N-rays on the other senses, I have found, to 
begin with, a very distinct effect on the sense of taste. If a 
trace of some highly flavoured substance is put on the end of 
the tongue such as camphor, aloes, salt, or sugar, keeping the 
mouth open, the breath held, and the palate raised so as to 
avoid all olfactory influence, the approach of a radiating 
source, such as a ball of tempered steel, reinforces or creates 
the sense of taste. The same thing happens when salt or 
other substance is diffused in the mouth instead of keeping it 
on the end of the tongue. .Are there points of the brain on 
which N-rays can act by determining an increase of the sense 
of taste? After experiments with different parts of the 
cranium, I h.ave only found a certain degree of action in one 
parietal zone, next to that which acts on vision, perhaps a little 
behind it. The study of hearing is more difficult, because of 
the precautions to be taken in order to prevent the currents 
of air displaced by breaking the source of radi.ition interfering 
with the conditions of arrival of the sound. It can be done, 
however, by making use of secondary radiations. Now, in 
taking as the .source of sound a watch held at the extreme 
distance at which the sense of hearing c-an perceive it, I have 
only clearly proved some increase of sound when the terminal 
plate was placed right above the ear at 7 to S centimetres from 
the orifice of the ear, which appears to confirm the idea of an 
excitation affecting the central centres of hearing. 



The Single-Phase Motor 
in Germany. 

Thi-: single-phase tr.ictiou motor which has been designed 
by the Union IClectric Company, Berlin, according to Wmter 
and luchberg's data, and which is being tried on the Johan- 
nisthal-Spindlersfeld suburban line, near Berlin, is thus de- 
scribed bv our Berlin correspondent : 

The motor includes a stator similar to those of ordinary 
induction motors, containing a single-phase coil arranged in 
notches, and a collector armature which is designed like the 
armature of a direct current motor, and to which two sets of 
brushes with axes perpendicular to one another are fixed. 
The first set, the axis of which coincides witli the axis of the 
stator coil, is short-circuited. It carries tlie working cmrents 
proper. These are induced by the field in the direction of 
the axis of the stator coil of a series transformer that is niserted 
in the main-current circuit, and carries only magnetising cur- 
rents. The magnetising currents produce a transversal field 
F perpendicular to the field </>. by which, in conjunction with 
the stator current, the efficient torque is produced. The 
presence of two separated fields enables the motor to work 




5ingle"Phase Motor in use on the Spindlersfeld Railway. 

without sparking. The electro-motive force generated in a 
winding that is short-circuited by a brush through the induc- 
tion of the field F is perfectly compensated as the speed of 
revolution increases, by the electro-motive force due to the 
rotation in the second field ip. That would be impossible in the 
case of monophase series motors, where, in the winding short- 
circuited through a brush, an electro-motive force independent 
of the number of turns, and incapable of being compensated, 
is induced. 

Moreover, by the rotation of the armature, an electro-motive 
force is induced in the exciting circuit of the armature which 
is able not only to compensate perfectly the undesired electro- 
motive force of self-induction of the circuit, but at the same 
time the electro-motive force correspondmg to the primary 
and secondary leakage. With an increasing number of revolu- 
tions the power factor will thus approach the value cos <(> = i, 
this value being maintained constant within wide limits on 
account of the unique regulation. Without any prejudice to 
motor efficiency, the air gap may therefore be made as great 
as in the case of direct current motors, and open stator 
notches may be used instead of closed notches. The ratio of 
the exciting' transformer is regulated by the insertion or dis- 
connection of windings. In the case of the series transformer 
being adjusted for a given ratio the motor will behave in a 
way (juite similar to direct current series motors, lioth the 
current intensity and the torque having the maximum value at 
rest and decreasing for incre.ising angular speeds. In the 
case of the ratio of the series transformer being diminished, 
the characteristic curve of the motor is displaced so as to 



94 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



have the same torque as previously observed with a given 
numl^er of revolutions Mj appear only at a number of revolu- 
tions Mi (superior to Mj). The same number of revolutions 
will now correspond with a hij^her torque than before, the 
torque at rest being evidently also higher. 

The motor is started by altering the ratio of the regulating 
transformer. The current of the c.xcitor brushes being thus 
interrupted at rest, the primary coil of the series transformer 
will act as a reaction coil, and the whole motor will be traversed 
only by a very small current. It will thus be unnecessary to 
open the primary coil of the motor when stopping. It is suffi- 
cient to open the exciting circuit (low tension coil) because the 
motor works only in the case of the exciting circuit being 
closed. 

The motors of the Spindlcrsfeld cars have an output of 
about 100 H.P. hours: they have four poles and a monolateral 
air gap of 3 mm. The total weight of a motor, including the 
small toothed wlieel, is 2140 kg., the weight of the exciting 
current transformers common to both motors being iioo kg. 
As regards the arrangement of the connections, the direct 
current multiple unit system of the Union Elektricitats GescUs- 
chaft has been used and slightly modified. Two cars are being 
used in connection with the johannisthal-Spindlersfeld trial 
runs, in addition to three trailers, each 16 tons in weight. The 
experimental trains arc run on the same track as used for the 
regulation steam trains, and are inserted between the steam 
trains according to a fixed time table. The cars are designed 
for a maximum speed of 40 km. per hour, though speeds as 
high as 60 km. are sometimes reached. The motors have 
given full satisfaction even in the case of the highest strains, 
the whole train, including two motors and three trailers 
(155 tons), being often arranged and driven by the two motors 
only. The perfect independence with respect to the line ten- 
sion has proved a special advantage as compared with the 
rotary current system, two-thirds of the line tension having 
been sufficient to maintain the regular service, while starting 
and running at a speed of about 30 km. was possible with 
40 per cent, of the motor tension. 

A. G. 

Recent Explosions. 

By Charles Davison, Sc.D., F.G.S. 



Interesting evidence with regard to the propagation of sound 
by the atmosphere is afforded by the firing of heavy guns 
during reviews and sham fights, and by explosions in manu- 
factories of dynamite and nitroglycerine. Examples of the 
former class have been given in two recent papers. ■ During 
the great naval review at Spithead on June 26, 1897, held in 
honour of the late Queen's Diamond Jubilee, the sound of the 
first salute was heard as far as Weston, near Hath, at a distance 
of 71 miles. Again, on July 18, 1900, when the I'rench Presi- 
dent visited Cherbourg, a sham fight took place between 
two portions of the French fleet, giving rise to disturbances 
that were mistaken for earthquakes at many points along 
our southern coasts. The reports were heard from 
Dawlish and Exmouth on the west, to Brighton and 
Henfield on the east, the distance from Cherbourg to the 
latter place being 107 miles. Lastly, during the funeral 
procession of our late Queen, on February i, kjot, the 
minute-guns were heard as far as Alderton, near Wood- 
bridge, in Suftblk, which is 139 miles from Spithead, 

In the present paper, I propose to describe similar 
evidence derived from two recent explosions, the first at 
Hayle, on January 5, of the present year, the second at 
Avigliana, near Turin, on January 16, 1900!. 



♦ "The distance to which the firing of heavy guns is heard ; " 
Nature, vol. Ixii., 1900. pp. 377-379: "On tlie audibility of the 
minute-guns fired at Spithead, on February i: " Knowledge, 
vol. xxiv., i9oi,pp- 104-105. 

f For the account of the H,-xylu exiilosioii, I have relied on the 
reports which appeared in the M'estern Morning AVa-s (Plymouth), 
and on replies to ,a letter whicii the ICditor of that paper kindly 
inserted. Dr. M. Baratta has puljlislicd an interesting report on 
" Lo scoppio del dinamiti-ficio cH .\vigliana c la geo liscia (16 
gennaio, 1900) : " Turin, 1900. 



The HaLyle Explosion of January 5, 1904. 

The works of the National Explosives Company at Hayle 
are situated on waste land, known as Upton Towans, about two 
miles north-east of Hayle and between three and four miles 
east of St. Ives. To reduce all risks to a minimmn. the 
separate buildings are isolated as much as possible ; and, to 
lessen the loss of life, in case an explosion should occur, the 
number of men employed in any building is always small. It 
was no doubt owing to the observance of these precautions 
that the loss of life during the recent disaster was compara- 
tively slight. 

At the time of the explosion (10.55 a.m.), nitro-glycerine was 
flowing down a gutter from the precipitating house to the 
filtering house, the latter lying about 400 yards north-west of 
the former. Only one man was working in the precipitating 
house and three men in the filtering house. It appears tliat 
the precipitating house was the first to explode, and that, 
owing to the temporary connection by means of the gutter, 
the filtering house followed immediately. This conclusion 
rests on the evidence of an eye-witness ; on the fact that 
persons to the south-east of the houses heard two reports 
separated by from li to 2 sees., while those in the opposite 
direction heard only one; and on the cDndition of the gutter, 
which was not covered by the debris from the precipitating 
house. Both houses were, of course, destroyed, and their 
occupants killed instantaneously. As to the cause of the ex- 
plosion, it can only be surmised — but the surmise is a probable 
one — that it was due to the fall of some heavy weight, cither 
of one of the lead cups used to catch the droppings from the 
taps, or, more prol^ably, of the lid of one of the tanks. In any 
case, the disaster must have been purely accidental in its 
origin. 

The results of the explosion were visible for several miles 
around the works, chiefly in the breakage of glass. At Hayle, 
many windows were blown out. At St. Ives, the damage was 
estimated at not less than £200, but its distribution was par- 
tial, some houses suffering and others close at hand escaping ; 
and it is worthy of notice, though the peculiarity has been 
recorded before, that the windows, especially in houses facing 
the works, were blown, not inwards, but outwards. Similar 
damage also occurred at St. Erth (3* miles from the works), at 
Leedstown (4 miles), and, though to a mtich less extent, at 
Penzance (distant 9 miles). 

A suiall oscillation of the ground was also noticed in the 
surrounding district. At St. Ives, according to my informant 
quoted above, the vibrations could not be distinguished from 
those produced by an earthquake. At much greater distances 
windows were shaken ; but this must have been caused by air- 
waves. Observations of this kind were made at several 
places in Devon, at Ivybridge and Modbury (68 miles), near 
Torrington (74 miles), at Paignton (83 miles), Torquay 
(85 miles), and Teignmouth (88 miles). 

The distribution of the places where the reports were dis- 
tinctly heard is shown in the sketch-map in fig. i. To the 



Scalt al Milts 



HaTtlanS 

Fulford 




Fig. 1. 



May, 1904."' 



KNOWLEDGE & SCIENTIFIC NEWS. 



95 



north-oast, the explosion was audible around Holsworthy 
(62 miles from the works), Hartland (fiS niilosK and Torring- 
ton: and to the east at many places in South ncvon as far as 
Exeter, which is not less than ()o miles from the centio of dis- 
turbance. Thus the sound must have beon heard over nearly 
the whole of Cornwall, and the ,i,'reater part of Devon, or over 
a total land-.area of about 3000 sijuaro miles. 

In the case of the minute-guns fired .at Spithead on Feb- 
ruary I, icjoi, a curious anomaly was observed. In the imme- 
diate neighbourhood of Spithead, the sound-waves were 
almost or quite inaudible, and it was only at a distance of 
50 miles or more up to about So miles that .they attracted 
general attention. Owing to contrary winds, the somul-waves 
were refracted over the heads of observers near at hand, and 
were brought down again by favourable winds to the earth's 
surface at greater distances. The Hayle explosion affords 
another instance of this remarkable eft'ect. .\t Camborne, 
which is only 4 miles east of the works at Hayle, no one, 
according to one of my informants, seems to liave heard the 
reports, and, he adds, the wind at the time was blowing in the 
contrarv direction. 

The Aviglia-na. Explosion of January 
16. 1900. 

The little town of .Avigliana hes in the valley of the Dora 
Kiparia, a tributary of the Po, about 14 miles west of Turin. 
As at Hayle, the various buildings which constitute the dyna- 
mite factory are isolated from one another, the whole being 
comprised within an area of about 50 acres. 

The first and greatest explosion occurred in the building in 
which the nitro-glycerine was prepared, and which, at the 
time, was estimated to contain about 400 kilogrammes of this 
material. This was followed by the explosion of nearlv 12,000 
kilogrammes of dynamite and fulminating cotton contained in 
magazines which were probably ignited by the fall of burn- 
ing materials from the first building destroyed. 



Scale oi TVTiles 



O 10 7J) io UO io 



A-t^UTtO^ 






Pai 



I 
I 

a. ' 

\ 
I 

\ 
o \ 



1 \ 

1 ^ 




Fig. 2. 



The curves in the accompanjnng sketch-map (fig. 21 give 
some idea of the distribution of the damage and other effects 
due to the explosion. The area of maximum destruction was 
practically co-extensive with the factory itself. At Avigliana. 
which is about half a mile distant, all the window-panes were 



broken, and in several of the oldiu- houses cracks were made 
in the walls .-ind arches. Similar, (hough somewhat slighter, 
damage occurred at several neighbouring places, all inclndid 
within the curve marked n, which cmilains an area of .iliout 
So stjuare miles. Outside this central area lies a /one bounded 
by the curve h, containing about iSo s(|uare miles and reach- 
ing to the western suburb of Turin, within which manv, but 
not nearly all, windows were broken. In the next zone, lying 
between the curves b and r, the air wave was strong enough 
to make doors and windows rattle. It will be noticed that 
the dynamite factory is at some distance from the centres of 
all three curves, the last of which (i ), indeed, extends 40 miles 
east of Avigliana and only eight mil(;s to the west. 

Beyond the latter curve the only effect observed was a 
rumbling sound like that of distant thunder or a cart of wood 
being unloaded. This was heard at i-onsiderablc distances in 
some directions, but the peculiar form of the curve (/ which 
bounds it is in part, no doubt, owing to a defective series of 
observations. Towards the south-east it reaches as far as 
S.avona (75 miles), towards the east to Pavia (87 miles), and 
towards the north-east as far as Lugano (qij miles). On (lie 
other hand, towards the west the sound was inaudible at Susa 
and Fcnestrelle. 1> )lh of which are only 17 miles from Avig- 
liana. 

Dr. Mario Haratta, who has stuilii'tl this ex])losion, considers 
that the restriction of the curves towards the west is in great 
part due to tlie form of the land-surface. Without under- 
rating the effects of the wind, the direction of which at the 
time of the explosion is unknown, he points out that tlie path 
of the waves would be obstructed by the mountain ranges 
lying to the west and south-west, wliile the open ground along 
the valleys of the Dora and Po would allow free passage to the 
sound-waves in other directions. Comparing the curves of 
lig. 2 with a contour-map of the district, he finds that the 
rc]-)ort of the explosion was never he.ard in places situated at 
an altitude of more than 1000 metres. 




ASTRONOMICAL. 

A new form of Dipleidoscope. 

In a brief note communicated to the Royal Dublin .Society, 
.Sir Howard Cirubb describes a simple little instrument for 
readily determining the true time by observation of the sun. 
The instrument in (juestion, the dipleidoscope, was originally 
devised more than sixty years ago by E. J. Dent. It consisted 
of a right-angled prism so placed that the sun, when near the 
meridian, could be viewed in it obliquely, when two images 
were seen, the one due to rcllection from the first surface, the 
other to double reflection from the- two inner surfaces. The 
two images would therefore appear to move in different direc- 
tions, and when the prism was properly set would overlap 
when the sun was on the meridian. The instrument, however, 
as originally devised, was open to some serious ol^jections. 
The one image of the sun was faint, the other excessively 
brilliant, and neither being magnified, the observation was 
only a rough one. By covering one-h.alf of the prism with 'a 
film of sulphide of lead, and by adding a lens of 20 feet focus, 
Sir Howard Grnbb has been al)le to make the two images of 
equal brightness, and sufficiently large for an imskilled 
observer to determine tlie lime to the nearest second. 

# « * 

RegistraLtion of Sta.r Transits by 
Photography. 

Sir Howard (irubl) has made an exceedingly in,i<enious yet 
simple suggestion for getting over the difficulty which has been 
experienced in employing photography to register star 



96 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



transits. The photographic plate must be made to travel 
if the registration is to be extended to the fainter stars, and 
the rate of motion should vary with tlie declination of the 
star. The suggested solution would place the object glass of 
the transit instrument in its horizontal axis, and the photo- 
graphic plate would travel on the arc of a circle, the centre of 
which coincided with the centre of the object-glass. This arc 
would be carried by a polar axis, the prolongation of which 
would pass through the centre of the object-glass. If the 
polar axis were driven uniformly by clock work, as in the 
ordinary equatorial, the plate would always move at the 
pniper rate for the declination of the star to which the tele- 
scope was pointed, and would .ilways lie in the focus of the 
transit telescope. 

* ♦ ♦ 

Burnham's Mea.sure of Double Stars. 

.•\mongst the decennial publications of the University of 
Chicago is a memoir by Frnfessor S. W. Biirnham on his 
" Measures of Double Stars," made with the 40-inch refractor 
of the Verkes Observatory in igoo and igoi. The memoiris 
one of very great importance, because the work undertaken 
by Mr, Burnham was the re-observation of stars which had 
been neglected, in most cases entirely, for some seventv or 
eighty years. The majority therefore are wide, or verv wide, 
pairs, and could have been successfully dealt with by the 
instruments in the possession of not a few amateurs, so that 
the devotion to them of the largest telescope and the most 
gifted ob.server in the world is something to be regretted. But 
since there was none other fulfilling the dutv, Mr. Burnham 
has performed a great public service in discharging it, and 
incidentally has succeeded in discovering some eighteen new 
pairs, some of which are evidently of \'erv high interest. 

* « * 

Mr. Lowell on Changes in the Ma.rtian 
Canals. 

Three papers reccntlj' published by Mr. Lowell carry his 
researches on Mars a distinct stage fmiher. Two of these are 
issued as Bulletins Nos. 7 and 8 of the Lowell Observatory, 
and deal with the variation in colour of the Mare Erythasum 
and the alternating appearances of the canals Thoth and 
.\menthes. The third paper, entitled "The Cartouches of 
Mars," was communicated to the .American Philosophical 
Society. In this last Mr. Lowell discusses some 375 drawings 
of the planet, made during the opposition of 1903 from 
January 21 till July 26. Eighty-fivo canals were observed, and 
each canal on the average might have been seen one hundred 
times. For each canal a curve or " cartouche " was drawn 
out to exhibit the percent.ige of times that it was observed 
wlien, from the presentation of the planet, it should have been 
visible, for different intervals after the sunmier solstice. The 
mean cartouches for the different zones are far from being 
convincing, and represent the smoothing out of many discord- 
ances. It may be granted, however, that there is some slight 
resulting evidence that on the whole the date of greatest dis- 
tinctness for a canal falls later in the summer of Mars in pro- 
portion to its distance from the pole. This darkening of the 
canals proceeds towards the equator at a speed of 53 miles a 
day. Mr. Lowell considers this as motion in the face of 
gravity, the equatorial radius of Mars being eleven miles 
greater th.in the polar, and as demonstrating that the canals 
are waterways and that the water is raised to this height by 
artificial means. The Thoth and the .■\menthes offer a case, 
according to Mr. Lowell, of alternative canals, the one canal 
being visible in one season and the other in another. Mr. 
Lowell also finds that the Mare Erytha;um shows a distinct 
bl';e-green tint at the time when he infers there is most moisture 
in the region and a chocolate-brown when there is least, a 
change he ascribes to the decav of vegetation. 

* * * 

Sunspots and Terrestrial Magnetism. 

Professor Ricco contributes ;in inijiortant memoir on this 
subject to the Societa degli S])ettroscopi It.aliani. He refers 
at length to Mr. Maunder's recent paper on the nineteen great 
m.agnetic storms of the last thirty years, and fully adopts his 
conclusion that there is a real connection between sun-spots 
and such storms. Mr. Maunder found that the storms began on 



the average 26 hmii-. ilter the transit of a great spot across 
the central meridian of the sun. Professor Ricc6 finds that 
the maximum violence falls about 455 hours after the transit. 
As the mean duration of a storm is a hours, the two deter- 
minations are almost precisely in accord. Referring to a num- 
ber of suggestions which have been made to explain the sun's 
influence on terrestrial magnetism. Professor Ricco appears to 
favour that of Arrhenius, who suggests ions, driven from the 
solar surface by reason of the pressure of radiation : their 
velocity being nearly tliat indicated by the interval mentioned 
above. 



ZOOLOGICAL. 



Ea.rly Opening of the Bright Eye. 

In a note to certain observations on the gestation of the 
badger, published in the March number of the Zoolof;ist, Mr. 
A. Heneage Cocks records the following \ery remarkable cir- 
cumstance : " I have never seen the fact noticed," he writes, 
■• that the right eye of young mammals opens before the lelt. 
I do not remember an exception among wild animals, nor even 
among domestic animals, though it is very likely some occur 
in the latter class. From the time the lids of the right eye 
begin to part to the time the left eye is fully opened takes 
generally from 36 to 40 hours." The fact is as new to us as it 
is to Mr. Cocks, and requires an explanation. The suggestion 
naturally occurs that the phenomenon is coimected with 
"right-handedness" in the human species; but before such an 
explanation can be accepted, we want to know whether car- 
nivorous and rodent mammals, and the membersof such other 
groups as have the young blind at birth, display a similar 
preference for using the right limb. The horse, it is well 
known, di.splays a decided tendency to " lead with the left 
foot ; " but in this species, in common with other ungulates, 
the young are born with their eyes wide open. And what 
holds good in this respect with domesticated horses may not 
obtain among carnivores and rodents. 

The "Pearl Organs " of Fishes. 

Tiie males of certain species of North American fishes 
develop during the breeding season what are known as " pearl- 
organs." These are hard spine-like thickenings of the epi- 
dermis, sometimes forming rows on the sides of the tail and 
on the anal fin. Their use long remained unknown. Mr. J, 
Reigh ud, of Michigan Universit}', finds, however, that they 
are employed by the males of some species for fighting and in 
building their nests, while in all the species they are used for 
holding the spawning female. 

Whale Collisions. 

Two instances of the sudden destruction of whales by colli- 
sion have recently been recorded in the daily papers. In the 
one instance the look-out on a liner noticed a large whale dis- 
porting himself OT the surface of the water immediately ahead, 
but, thinking that the monster would get out of the way in 
time, the vessel was allowed to pursue her course. Instead, 
however, of moving, the whale .remained where he was, and 
was caught " amidships " by the bows of the steamer, which 
cut him conipletelv in two. For two or three miles, it is said, 
the vessel ploughed her way through water crimsoned with 
the leviathan's blood. The second case is recorded in a tele- 
gram sent from Vladivostok on March 30. " A violent ex- 
plosion," runs the message, " recently occurred at sea in 
Possiet Bay, the cause of which could not be ascertained. 
Two days later the bodj' of an enormous whale was washed 
into the bay by the tide, the creature having evidently collided 
with and exploded a mine." 

Monkeys aLnd Altitude. 

A recent issue of the ^//i of the Roval Academy of Rome 
contains an account of the effects produced on baboons and 
monkeys bv conveying them to a high elevation on Monte 
Rosa. The ill effects seem more pronounced than in the case 



May, 1904.] 



KiNOWLEDGE & SCIENTIFIC NEWS. 



97 



of human beings. The action of the low haroiuetiic 
pressure appears very similar to that of uarootics, prodiuing 
at first unusual activity and excitement, follovved l)y sleepiness, 
iusensibility, aiid, finally, death. 



The Brairv of Man a-nd Apes. 

For many years Professor G. lUliot Smitli, of the Msjyptian 
Government School of Medicine, has been devotinj; his atten- 
tion to the study of the brain in man and other mammals. 
Recently, in the Anntoinischc'r Aiizcirffr Ijcnay, he has pub- 
lished a preliminary account of what appears to be an exceed- 
ingly important discovery. The human brain, as known by 
European specimens, has been supposed to difter from that of 
apes and monkeys by the absence of the so called simian fold 
(" Aftenspalte ■') on the posterior portion of the main hemi- 
spheres. On studying a large series of Itgyptian ,ind Sudani 
brains. Professor Smith finds, however, that this simian fold, 
or sulcus, can be distinctly recognised. 

" It is easy," he writes, •' to select examples from the series 
of Egyptian and Sudanese brains in my possession in which 
the pattern formed by the occipital sulci on the lateral surface 
of the hemisphere in individual anthropoid apes is so exactly 
reproduced that the identity of every snUus is placed beyond 
reasonable doubt. . . . .\nd if we take individual examples 
of gorilla brains it becomes still easier to match the occipital 
pattern of each of them to numerous human brains. . . 
It is easy to appreciate the difficulties which have beset inves- 
tigators of European types of brain, and to understand the 
reasons for the common belief in the .absence of the supposed 
distinctly simian sulci in the lateral aspect of the occipital 
region of the human brain." 

Thus disappears one more of the supposed structural dis- 
tmctions between man and his nearest relatives. 



Zebra Ta-ming at the Zoo. 

AUintere.sted in the progress of the Zoological Society's .Mena- 
gerie in the Regent's Park, and the attempts now being made 
to render it more attractive to the general public, will have 
heard with unfeigned regret of the sudden death of the Grevy 
zebra stallion shortly after the first trial at breaking it for the 
saddle. With regard to the experiments made for timing all 
the specim<?ns of the zebra at present in the collection, it 
appears that the smallest and quietest of the three mares was 
some time ago broken in with very little trouble. ( )n March 15, 
'•Jess," a larg<'r and somewhat less docile mare, was taken in 
hand, with most successful results; and the same afternoon 
the third mare was handled with equal success. .All three 
mares have since been going about quietly in harness, although 
it was deemed advisable not to take "Jess," as being by far 
the most powerful, beyond the limits of her paddock. On the 
following day. March 16, the Grevy stallion was taken in hand, 
although it was never intended that he .shoidd be employed 
for riding purposes. Although some temper was displayed by 
the stallion, he was eventually broken w ith complete success. 
During the next two days he seemed perfectly well, bat he 
showed signs of being out of condition on Saturday, and, after 
refusing to get up on the morning of the Sunday, he died that 
night. 

The post-mortem examination was made on Wednesday, 
March 23, by Dr. Salaman, Director of the Pathological Insti- 
tute at the London Hospital. The immediate cause of death 
was heart-failure, but Dr. Salaman was unable to find evidence 
of the actual cause of failure ; the complete absence of signs 
of injury or disease being similar to the case of a Grant's 
zebra examined by hiiri at the beginning of March, which 
had died in the Gardens without having undergone any 
training or breaking-in. 

Although it is obviously impossible to be certain that the 
death of the Grevy was unconnected with the breaking-in, it 
is satisfactory to know that there was no sign of injury to any 
of the internal organs. The bones were, however, unusually 
brittle, and the stallion was much older than had been sup- 
posed. Our readers will be glad to hear that this untoward 
event is not to be allowed to interfere with the progress of 
zebra-training. 



The Collections of the "'Discovery." 

According to tln' daily papers, the re>-ults of llie expedition 
of the " Discovery " to the .\ntarctic do not appear lo havi' 
■added anything very striking to our biological knowledge. 
So far as zoology is concerned, the most important item is, 
perhaps, the discovery of a " primitive type " of insect. \'alu- 
.able information with regard to the bird-life is, however, said 
to have been obt.dned. Most important of .all a]ipe,irs to be 
the discovery of a number of fossil-plant remains, which are 
said to confirm the theory of a former land-connection, by 
wav of " -Vntarctica," of the southern continents and isl.uids. 

BOTANICAL. 



An Abnornnal Fern. 

.[spiiliuiii iiiioiiuihiin is a fern fovmd growing at high eleva- 
tions in Ceylon. It closely resembles the British A. iiaiU'tiluiii, 
of which it may be merely a form, and very remarkable on 
account of the sori being developed on the upper instead of 
the under side of the fronds, the usual position for them. The 
plant is now in cultivation in this country, its large liandsome 
fronds rendering it of consideral)le horticultural merit. The 
species was first described by Sir William Hooker nearly half- 
a-century ago under tlie name of i'dlijpotliuni annnuilum, and 
he regarded it ;is an abnormal form of P. veslitum. He found 
that the indusium was entirely absent even in the youngest 
stages of the fructification, while in P. vestituin it was very 
earlv deciduous. Other ferns are known to occasionally 
develop a few sori on the upper side of the frond, as in Dcpana 
Moiiii-i, wh('re they are confined chiefly to the margin, ;uid 
sometimes in AspU-niiiiii friihuinanes. Sir Willi.iin Hooker 
refers to a specimen of this species, collected in Italy, in 
which, in addition to the numerous sori on the under side of 
the frond, there was one pinna "bearing a solitary sorus on 
the disc of the upper side." In the specimen from which Aspi- 
dinni anotnaliim was first d(^scril)ed a few sori were found on 
the under side of two or three pinnules of a frond. 

A Primitive Food. 

Professor F. W C'oville h.is ju;,! pulilished an interesting 
paper on a primitive food of the Klamath Indians, produced 
bv a congener of our yellow water-lily (Niiphar lutcuni), and 
known under the native name of Wokas. This plant is A'. 
pulyscpiilum. called by .American botanists N ipupluca polyscpahi, 
and is found in great abundance in the reservation occupied 
bv the Klam.ith Indians in the south-western corner of the 
plateau of eastern Oregon, at the eastern foot of the Cascade 
Mountains. A huge marsh in this reservation, known as the 
Klamath M.arsh. contains no less than ten thousand acres of the 
Wokas, which fiourish to the exclusion of almost every other 
kind of vegetation. The seeds are subjected to various tedi- 
ous processes by the natives and ultimately furnish a wholesome 
farinaceous food, which is regarded as a great delicacy, and 
which Professor Coville thinks might be successfully brought 
into commerce as a bn-akfasl food, though he does not con- 
sider the cultivation of the plant for commercial purposes to 
be feasible, and the supply of the seeds would be dependent 
on the wild crops. The order Xympha-^acea; is not impnrtant 
economically. The seeds of the Victoria rei^ia are eaten by 
the natives of Guiana and Pirazil, and the stem of the Sacred 
Lotus (Xiliinihiuni ■ipriiiisuin) "is used as food in India and 
China, though probably only in times of scarcity." 

PHYSICAL. 



On a Novel FLadiation Phenomenon. 

Mr. J. J. Taidin CHAnoT-- some time ago ascertained whether 
selenium in its conductive modification, being sensitive to 
light, may give rise to radio-active phenomena. To this effect 
he used a selenium cell of the Shelford Hidwell type, the 

* Physihal Zcitschr., No. 4, pp. 103-104, 1904. 



98 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



effective mass of which was uniformly distributed on the sur- 
face of a platinum wire. After having been in the dark for 
many weeks, the platinum selenium surface was covered, at a 
red illumination, with a sheet of silver bromide jelly to which 
a sensibiliser absorbing the yellow and green rays was added, 
an aluminium strip bent at right angles being interposed. 
After the whole system had been kept in the dark for another 
48 hours, the same experiment was repeated, using a fresh 
silver bromide jelly sheet, while a current of about no 
microamperes traversed the selenium. Now the following 
results were observed on the developed jelly sheet : — 

In the first case, some bright spots corresponding apparently 
to the outline of the aluminium angle were noted on a dark 
background, whereas, in the second case, a dark silhouette 
of the whole of the angle without any details resulted on a 
bright background, some brighter narrow transversal bands 
being visible at the same time. These bands were produced 
more efficiently in the case of repeated expositions, thus 
allowing of ascertaining that they are due either to the parallel 
platinum wires or to the selenium interposed between each 
two of these, or finally to the points of contact between the 
platinum and selenium, where the Peltier effect must give rise 
to an evolution of heat either positive or negative, on the 
passage of the current. 

On continuing these experiments. Mr. Chabot noted the fact 
that the back of the plate bearing the platinum selenmm wire 
was equally capable of affecting the silver bromide jelly, dark 
silhouettes on bright background being then obtained. As to 
the question whether these results are an evidence of the 
existence of some novel radiation, or else an emanation from 
the surface of conductors, the author hopes to publish in due 
course some further investigations allowing of more definite 
conclusions being drawn. 

R-adium a-rvd Heat. 

In the course of an experimental investigation of the in- 
fluence of radium on the rate of cooling of a body placed in a 
gaseous medium, Mr. Georgiewsky. in a paper recently read 
before the Russian Physico-Chemical Society, arrives at the 
following conclusion : — 

1. The rate of cooling of heated bodies in the various gases 
is not modified under the influence of radium. 

2. The rate of cooling of non-electric heated bodies placed 
in one of the gases examined (hydrogen, lighting gas, air and 
carbonic acidi on being exposed to the action of radium is 
augmented in the case of the heated bodies being electrified. 
The rate of cooling in this case will augment not only under 
the simultaneous influence of the a, S and 7 rays of radium, 
but as well under the exclusive action of ;3 and 7 rays, 

3. The increase in the rate of cooling of a heated body is 
greater as the body is negatively charged. 

4. The relations existing between theincreasein the thermic 
conductivity and the potential of a charged and heated body 
may be represented by means of curves analogous to those by 
which Mr. Townsend expresses the connection between a : p 
and X : p for the same gases {Pliil. Miif;. 6 ser. V. 5, p. 571). 

A. G. 

ORNITHOLOGICAL. 



By W. P. Pycraft. A.L.S.. F.7.S,, M.R.O.U.,&c. 



Breeding Habits of the Common Buzzard 

[Buica vulgaris). 
Professor J. H. Salter gives an exceedingly interesting 
account of his observations on the nesting halrits of the 
Common Buzzard in the '• Zoologist " for March. Of the 
three young which are almost invariably hatched, he remarks 
that, in the hill districts, the oldest bird will commonly kill one 
or both of the younger nestUngs ; apparently for the' purpose 
of securing their share of the food brought by the parents. In 
support of this view he points out that this unnatural behaviour 
is not noticeable when the young are reared in the more fertile 
valleys where food is plentiful. 



He also describes a curious habit which the parents have 
of decking the lining of the nest with freshly-plucked leaves 
and twigs, especially of birch, and rowan, and bracken. 

Birds breeding in Wales furnished the material for this 
extremely interesting history. 

* ± * 

Greenland Falcon in Donegal. 

It has just come to light that .in inunature bird of this 
species was trapped in Donegal in December last. This 
makes the thirty-second record of this species for Ireland, 
and the tenth for Donegal. 

Nutcracker in Northamptonshire. 

A trap set for " vermin "in February last, at Ty well, captured 
instead a Nutcracker, whilst one is reported to have been seen 
in Devonshire during the same month. 

The Emperor Penguin. 

A statement has been going the round of the daily papers 
to the eftect that one of the results of the newly-returned 
Discovery Expedition to the Antarctic has been the capture 
of the Emperor Penguin, a bird which had " not previously 
been found in these regions." Of course this is a mistake ; but 
we are glad to learn that the eggs of this bird have been taken, 
for they have not hitherto been, and will therefore form 
a welcome addition to the collections of the National Museum 
at South Kensington. 



All communications intended for this column should be 
addressed to : — 

\V. P. Pycraft, 

Natural History Museum, 

South Kensington. 

'^i "^i '^^ ^^i ""^i 

REVIEWS OF BOOKS. 



First Causes. 

The Old Riddle and the Newest Answer. By John Gerard 
S.J., F.L.S. (Longmans.) The old riddle which the Rev 
John Gerard tries, not to answer, but to state, is that which 
asks whether it is possible to explain the universe without 
admitting the existence of a Creator. The answer he gives is 
that no theory which has yet been formed can relieve us from 
the necessity of imagining a First Cause ; there must have 
been a God. a Divine Intelligence greater than any intelligence 
which man can attain. Mr. Gerard's conclusion is well stated 
in a quotation from the late Professor Baden-Powell — "That 
which requires thought and reason to understand must be it- 
self thought and reason. That which mind alone can investi- 
gate or express must be itself mind. And if the highest concep- 
tion attained be but partial, then the mind and reason studied is 
greater than the mind and reason of the student. If the more 
it be studied the more vast and complex is the necessary con- 
nection in reason disclosed, then the more e\"ident is the va.st 
extent and compass of the intelligence thus partially mani- 
fested . . . ." But though we have no quarrel with the 
conclusion that Mr. Gerard reaches, and though we may admit 
that it has been expressed in varying forms by the greatest of 
scientific men — by Kelvin, by Lamarck, by Sylvester, even by 
Huxle}- — there is a distinct objection to the means he has taken 
to reach it. He opposes the theory of Evolution by the doc- 
trine of Design. A very large part of his volume is occupied 
by an attack on Darwinism, which we cannot even admit to be 
a fair attack. Darwin's theory is not infallible: its too zealous 
advocates ha\e sometimes stretched it farther that it can legiti- 
mately be held to go. In any case it is but a working model, 
and, like the atomic theory, or the theor}^ of the ether, or the 
chemical theory of ionic dissociation, or the new theories 
based on radio-activity, it is to be regarded not as a complete 
explanation, but as a hypothesis which enables us to account 
for many of the facts. Even if it were completely true, it 
would not prejudice the belief in a Creator; if it were proved 
entirely mistaken it would not strengthen that belief. Why 



May, 1904.] 



KNOWLEDGE & SCIENTIFIC NFAVS. 



09 



then assail it as a factor in the argument ? If, on the other hand, 
the Darwinian theorj- be assailed on other than dialectic or 
theological grounds, then the tirst necessity is to be scrupu- 
lously fair, meticulously exact. W'c have not sp.ace to consider 
critic.-iUy all the quotations which Mr. Gerard brings forward 
as evidence against it : but we may briefly refer to one part of 
his case, which is contained in the chapters on the geological 
record. He (piotes with approval the attacks which Mr. 
Carruthcrs made in 1S76 .as President of the Geologists' Asso- 
ciation, and later in book form (iSySl, on the incompleteness of 
the bot.anieal fossil record, and its failure to show any connect- 
ing link between the greater divisions of plants. But Mr. 
Gerard entirely ignores the work which has been done since 
iSgS by Professor A. O. Seward, Dr. 1). H. Scott, and Pro- 
fessor F. W. OUver in fossil botany, and the opinions expressed 
by them. To quote but a single instance: Dr. D. H. Scott 
and Professor F. W. Oliver have within the last twelve months 
shown reason for connecting the Ferns with the Cycads; and 
have exhibited in Lyginodendron a seed-bearing fern. Not, 
however, to go into too great detail, we may quote from Pro- 
fessor Seward's British Association address an observation 
made by Darwin himself on the imperfection of the geologic 
record, " The crust of the earth, with its embedded remains. 
must not be looked at as a well-filled nniseum. but as a poor 
collection made at hazard and at rare intervals." And the 
transitions of form and species are not incompatible with evo- 
lutionary theory. 

A Chemical Conceptiun of the litlier. 15y I'rofessor I). 
Mendelceff. (London : I^ongmaus, Green, and Co.) The 
discovery of the radio-active properties of some of the metals. 
and the probability which Lord Kelvin remarked, that most 
substances are radio-active to a greater or less extent, has 
been one of the corroborative facts to sustain the electro- 
atomic theory of matter. That theory has been hesitatingly 
received by many chemists, who have not hesitated to dispute 
the objeeti\e reality of atoms — regarding them merely as 
vehicles for expressing relations between the elements — and 
who have seen in the extension of the theory so as to take in 
"atoms of electricity" or "electrons," or "twists in the 
ether," an unprovable hypothesis which they do not need to 
explain chemical inter-action. The attack on the physicists' 
conception of the atom of matter as an imperceptibly small 
system of forces in which electrons revolve at enormous speeds 
and possibly in concentric rings (not unlike a solar s3'stem in 
miniature, or the rings of moons about the pl.met Saturn) has 
not hitherto been very well directed. It has in at least one 
instance put forward an untenable explanation of some of the 
facts of radiation ; and while ignoring the fact that the 
•■ electron " theory does explain the radiation of radium and 
thorium very well, has offered no alternative theory. Pro- 
fessor MendeleefTs theory of the ether removes, however, the 
latter reproach, and offers a supposition which, though await- 
ing the test of mathematical examination on the part of the 
physicists, is an extremely interesting one. He boldly sweeps 
away the anomalies of believing the ether to be an all- 
per\'ading substance — rigid as steel, yet interpenetrating all 
matter; frictionless, but without weight — by imagining it to be 
a gas that has weight and substance, though it is of such 
extreme tenuity that it is capable of interpenetrating .ill 
other substances and incapable of offering a measurable 
resistance to their passage among its molecules. Its in- 
susceptibility to chemical combination is to be regarded as 
similar to a similar inertia on the part of helium or argon, or 
the gas emanating from radium ; its imponderabihty is not 
real, but due merely from the absence of an)' known means of 
weighing it. Professor Mendelceff calculates that this theory 
w'ould fulfil the requirements mathematically demanded from 
it if the ether, the lightest element, and its particles and atoms 
had an atomic weight nearly one-millionth that of hydrogen, 
and travelled with a velocity of about 2250 kilometres a 
second. We need not follow Professor Mendeleeff's theory 
in all its details, but it will not be uninteresting to summarise 
the way in which it responds to the demands put on it to 
explain radio-activity. Although the ether, or, as he calls it, 
the lightest of gases, x, has no power to form stable chemical 
compounds, it would not be deprived of the faculty of dis- 
solving in, or accumulating about, large centres of attraction 
— like the sun among heavenly bodies, or the heavy uranium 
and thorium atoms. If the ether be a gas x it must naturally 



accumulate from all parts of the universe towards the heavy 
suns, just as the gases in the atuiosphcre accumulate in a drop 
of water. Similarlv it will acemnul.ile towards the heaviest 
atoms of thorium or uranium. 1/ siuli ii spcciiil acciimiilitl'uin 
of ctlur atoms iihoiit tlu- iiioleciilcs of rndium and thorinin lie 
adiiiissihlejlicij mifiht lie expcctid to cxiiiint fccuUar phenomena 
dctci-mincd by the emission of 11 portion of this ether held hy 
partielen of normal mean vehicily and by new ether enlerinf; 
into the sphere of attraction. In short, the theory of tlic great 
Russian chemist is not unlike in form that explanation sug- 
gested l>v Sir William Crookes and Dr. Johnstone Stoney, .-ind 
partly confirmed by Lord Kelvin, that the radiation of radium, 
thorium. lS:c., is sustained by energy from without rather than 
from within. 

The lissential Kaffir. II is to the human interest of the 
Kafhr that Mr. Dudley Kidd devotes himself in his valuable 
and entertaining book, "The Essential Kaffir." (Adam and 
Charles Black.) He uses the word Kaffir in its broadest 
sense to include all the dark-skinned tribes of South Africa; 
his information concerning the people of whom he writes is 
intimate and varied, comprising the gleanings of a dozen years, 
repeated visits to their tribes, visits in which he associated 
with tliem in terms of intimacy, slept in their huts, watclied 
thi-ir h.ibits of life and their social and religious customs, 
memorialising them in many admiraljle and curious photo- 
grai)hs which add greatly to the value .uid interest of his book. 
There is, for instance, the photograph of the mother feeding 
her baby with sour milk out of her hand, while a lean dog 
watches the operation with symp.ithetic inteiest. In the next 
])hotogr.iph the dog is buing utilised as a napkin to lick the 
b.iby's face clean, while the mother holds its unwilling counten- 
ance- steady with one hantl while she guides the dog's head 
with the other. Mr. Kidd describes a night spent in a Kaffir 
hut in company with the Kaffir family and such household 
pets as a e.alf, a dog, roosting fowls, and others who shall be 
nameless, but who could scale even sandbanks of Keating. 
One feels as one reads that self-sacrifice in the cause of know- 
ledge could go no further. Very interesting are the chapters 
on Kaffir mental characteristics, on their nmsical instruments 
and games, and on their religious beliefs. Of their mental 
powers he notes the curious fact that the native children some- 
times absorb knowledge with a singular precocity, but as they 
develop their brains, as it were, seem to stop growing, tlieir 
energies appear to be absorbed in their bodily development, and 
whether caused by " meclianical formation of the bones of the 
skull or not, must fie left to men of science to settle ; yet the fact 
of stunted mental development remains." At the same timi' 
the natives are remarkable for their extraordinary memory of 
facts which interest them, such as the precedents in a legal 
case. In a book where every page is interesting, an adequate 
idea of its contents can hardly be given in so short a space. 
All such people as the Kaffirs here described must rapidly 
lose much of their individual character in contact with other 
civilisations, and a book th.it crystallises their essential charac- 
teristics from intimate observations lias a more than ephe- 
meral interest. 

Physical Chemistry in the Sciences, by Jacobus Vaii't Hoff. 
(Chicago: The University Press.) To the Decennial publica- 
tions of the University of Chicago have been added the series 
of lectures which were delivered there by the German chemist, 
Van't Hoff, and which deal with " Physical Chemistry in the 
Service of the Sciences." The lectures, lucid, terse, concen- 
trated, deal with Physical Chemistry in Pure Chemistry, in 
Physiology, in Geology, and in Industrial Chemistry. T'loni 
the last-named cliapter we may make an cxtnact which should 
be very serviceable in bringing home to the British nation the 
true reason for the growing strength of the German competitor 
in industries that for many years were chiefly British. " There 
exists in Germany," says Van't Hofi', " a very beneficial co- 
operation between laboratory work and technical work. Both 
go as far as possible hand in hand. After physical chemistry 
had made several important advances, and was firmly estab- 
lished in such a way th,al pure chemistry was assisted by co- 
operation with it. Professor Ostwald judged correctly that this 
co-operation would be valuable in teclinic.il directions. In this 
beliefhe founded the I':iectro-Chemical Society. . . . All the 
most conspicuous chemical industries of Germany are repre- 
sented in the Society, which has its own organ of publication. 
Nor has the stimulus to this co-operation come purely on the 



100 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



scientific side. That it comes from botli parties may be seen, 
for example, in the fact that a year ago Professor Goldschmidt, 
of the University of Heidelberg, was asked by the Director of 
the ' Badische .'\nilin-und-Soda Fabriken ' to give a series of 
lectures on this branch of science before the chemists of the 
factory, and did so with great success. .An opening up of new 
points' of view, rather than immediate practical results, was 
expected to flow from these lectures," all of which should 




A plate of tin affected by Tin Disease ^enlarged one and a half times), 

[Fwni ^'Physical Chem^ityy in the Sciences'^}. 

strengthen a case, already overwhelming, for the establish- 
ment of English Charlottenburgs. From V'an't Hoff's lecture 
on Industrial Chemistry, «e take also a plate illustrating a 
curious so-called disease of tin. It is rather a transition of 
tin from one form to another, and has been recognised as of 
actual occurrence since the time of .\ristotle. Van't Hoff de- 
scribed the beautiful methods, largely due to the investigations 
of Schaum and Cohen, by which the conditions which influence 
this extraordinary change have been determined. 

BOOK NOTICES. 



Geometr}'. In addition to •' .\ School Geometrv (Parts 
I.— IV. ; IV., V.)," by H. S. Hall, M..\., and F. S.'stevens, 
M.A. (Macmillani, which we received last month, and which 
provides a course of elementarj' geometry based on the recom- 
mendations of the Mathematical Association and on the 
schedule recently proposed and adopted at Cambridge, we 
have received also " Elementary Geometry " (Parts I. and II.), 
by Cecil Hawkins. M..\. (Blackie), which departs e\en more 
boldlv than other works based on the tenets of mathematical 
reform, and which, with practical illustrations, takes pupils 
and classes, not through the routine of Euclidian propositions, 
but acquaints them by progressive stages with the ascertain- 
able properties of '• Intersecting Straight Lines," '• The 
Triangle," " The Circle,'' " Polygons," and so on to areas and 
to numerical theorems treated numerically. 

Domestic Economy Reading Books, \ol. il., "The Marshfield 
Maidens and the Fairy Ordma," by Mrs. W. H. Wigley 
(Thomas Murby, 3, Ludgate Circus Buildings, E.C.). — Simple 
lessons in household duties are conveyed in narrative form. 

Logarithims for Beginnings, by Charles PickworthlWhittaker 
and Co., 2, White Hart Street, E.C.). — A simple introduction 
to the study of the subject, intended to give a more detailed 
and practical explanation of logarithms and their \arious 
applications than is to be found in text-books on algebra and 
trigonometry. 

Worked Problems In Higher Arithmetic, by W. P. Workman 
and K. H. Chope (,W. B. Clive, University Tutorial Press). — 



A collection of problems in higher arithmetic, intended espe- 
cially for students who are preparing for Civil Service E.xa- 
minations. It will also be of service to teachers. 

Tables of Multiplication, Division, and Proportion, by Robert 
H. Smith. M.I.M.E. (Archibald Constable).— These elaborate 
tables will be useful in the ready calculation of quantities and 
costs, estimates, interests, wages and wage premiums, Li;c. 

The Story of Creation, by Edward Clodd (Watts and Co 
Sixpenny Edition, with numerous illustrations and good type). 
— It gives an account of the theory of evolution in clear and 
popular form, dealing with the distribution of matter in space, 
the past life history of the earth, present hfe forms, the origin 
of life and of species, and social evolution. 

An Agnostic's Apology, and other Essays, by Sir Leslie 
Stephen, K.C.B. (Watts and Co. Sixpenny Edition.) — Con- 
tains Essay on " Materialism," Newman's " Theory of Belief," 
■■ Toleration." 

Remarkable Comets, by William Thynne Lynn, B.A., 
F.R..A.S. (Sampson Low, .Marston, and Co. New Edition). — 
It reviews briefly the most interesting — perhaps we should say 
the most popular — facts in the history of Cometary .Astro- 
nomy. 

A Safe Course of Experimental Chemistry, by W. T. Boone, 
B..-\.. B.Sc. (W. B. Clive, Unisersity Tutorial Press).— .\ short 
course of chemical experiments, designed to train students in 
solving elementary problems by experiment, in accuracy in 
their work, and in reasoning from observation. It is espe- 
cially intended for the London matriculant who intends to 
take the Intermediate Science Examination, or for students 
in training colleges who have to take the prescribed course in 
general elementaiy science. 

Second Stage Botany, by J. M. Lowson, M.A., B.Sc, F.L.S. 
(W. B. Clive. University Tutorial Press). — This is an adapta- 
tion of the •■ Text Book of Botany " to the requirements ot the 
second stage examination of the Board of Education, South 
Kensington. The first part of the book deals with morphology, 
histology, physiology ; the diagrams and illustrations are 
numerous and clear, and will be very helpful to students. 

Modern Navigation, by William Hall, B..\. (W. B. Clive, 
University Tutorial Press), is intended primarily as a text-book 
for students of navigation and also as a handbook for navi- 
gators. It will be found useful in the various examinations of 
the Royal Navy, the Mercantile Marine, and the Board of 
Education. The explanation of compass deviations and 
tides will introduce the student to more detailed works on the 
subject. 

Pocket Edition of the Works of John Ruskin (George .\llen). 
— A small and pretty edition of Ruskin reprints, light to hold, 
and pleasant to read. '• Sesame and Lilies," which deals 
with ''The Mystery of Life and its .Arts," and insists that 
'• those of us who mean to fulfil our duty ought first to live on 
as little as we can ; and secondlj' to do all the wholesome 
work for it we can, and to spend all we can spare in doing all 
the good we can." 

The Crown of Wild Olive ; Essays on '■ Work and War and 
the Future of England," and " Lectures on .Art" — Essays 011 
the Relation of .Art to Morals and the Relation of .Art to 
Use. These three volumes contain some of the most 
strenuous common-sense and right-thinking in Ruskin's 
works. 



Messrs. John Wheldon and Co., of Great Oueen Street, have 
issued a clearance catalogue of a miscellaneous collection of 
books. The volumes include works on botany, entomology, 
and ornithology. There are especially to be noted some 
works on fungi and publications relating to meteorology. 

Messrs. Isenthal's new catalogue is well worth attention for 
the completeness of the Rontgen-ray and allied apparatus 
which their manufacturers ofl'er. The very large and greatly 
increasing numbers of devices used in electro therapeutics 
and in the new methods of the light treatment of disease are 
specially noticeable. 

Messrs. Harry W. Cox's new catalogue of X-ray and 
high-frequency apparatus includes an extension of their 
pre%iously issued practical hints to beginners. These hints, 
covering work with X-ray coils, mercury and other interrupters, 
and describing the best methods of connecting rheostats and 
charging accumulators from the mains, are extremely useful, 
and mucli to the point. They add distinctly to the % alue 
and interest of the catalogue. 



May, 1904.] 



KNOWLEDGl' cS: SCIENTIFIC NEWS. 



101 



BOOKS RECEIVED. 



A Sysleraatic Survey of the Organic Colouring Matters, l>v A. G. 
Green. F.I.C., F.C.S. ^MacmilUii.) .-is. net. 

My Airships, by .\. Santos Dmnont. (Giant Richards.') 
Illustrated : 6s. net. 

Five Years' Adventures in the Far Interior of South Africa, li\- 
l\.("iordonl"innMiin.i;. (John Mnrray.) Illustrated; .;s. 6d.net. 

Radium and all About It, by S. Hottone. (Wliittaker cS: Co.) 
Illustrated : is. net. 

A Text Book of tieology, by W. Jerome Harrison, I'.G.S. 
(Blackie Cv: Son.) Illustrated :' .^s. 6d. 

Dyes, Stains, Inks, Varnishes, i'olishe-, &c., In- Thcmias Holas, 
F.C.S.. I-M.C. iDaubarn A: Ward.) Illustrated: 6d.net. 

Metal-Working, l)v [.C. I'earson. (Murray.) Illustrated. 2s. 

Practical Slide Making, by G. T. Harris! F.K.P.S. iIlitTe.) 
Illustrated : is. net. 

Phylogeny of Fusus and Its Allies, by .Vniadens W. Grabau. 
(Smithsonian Institution.) 

Researches on the Attainment of Very Low Temperatures, by 
Morris W. Travers, D.Sc. (Smithsonian Institution.) 

Nature's Story of the Year, by C. .V. W'itchell. ( Mslier Lnwin.) 
Illustrated : 5s. 

Notes on the Composition of Scientific Papers, by T. C. .\llbult, 
M.A., M.D., ,.S;c. (M.icmillan.i js. net. 

TKe AitcKison Prism Field Glasses. 

The .■\itehison Prism Field Glasses, specimens of which have 
been sent to us for review, represent a considerable .adaptability 
alike of mind and of method on the part of British opticians. 
The eftectiveness and popularity of the Continental prism 
sjlasses were such as to leave no doubt in the mind of 
opticians that in imitation lav the only form of successful 
competition, and that to imitation must be added improve- 
ment. In consequence a t;reat deal of money has been spent 
with this end in view; and the .\itchison glasses represent a 
very gratifying measure of achievement as a return on the 
outlay of expense and ingenuity. The principal features of the 
glasses that we have before us are the use of large object 
glasses, variable diaphragms, and improved means of 
focussing. With the larger object glasses are used prisms and 



I«PR1SM-/XI? 




The Black Line with arrow head shows the path of rays of light in 
the New Aitchison Prism Field Qlass. 

lenses of a higher index of rtfr.iction than ordinarily employed. 
The prisms are very much larger than in the German glasses. 
The introduction of variable diaphragms is a quite nt'w 
departure in the construction of field glasses. A p.air of Iris 
diaphragms are in this case introduced into the tubes close to 
the object glasses and ground together so that they are 
worked simultaneously from the toothed wheel on the central 
pillar. By this means, as in tlie photograpliic camera, .all 
unnecessary rays can be cut off when the light is brilliant, 
and in dull weather and at night the whole available aperture 
of the object glasses can be used, thereby effecting an immense 



ad\ .intage over the old form with fixed diaphragms. Another 
benefit is the rigidity of the body, which is secured by 
casting the two lubes and crossbars in one piece inste.id of 
building them up in separate parts as hitherto 

University College Lectures. 



Th- /ollou'iiig Courses 0/ Lectuycs wilL he dclivo'c.i duri)h^ May 

at the University CoUcj^e, Loiu/oii. 
Coursoof K) Lectures on the HISTORY OF M()Dl';im 

I'lIILOSOl'llV, by Mr. .\. Wolf, M...\. First 

Lecture, .\pril 26th, 4 p.m. 
Course of Lectures on COM PAR ATI Vb: LAW, by 

I'rof. Sir John Macdonei.i,, ^L.\., LL.L)., (".]]. 

Commencing April 26th. 
Courseof 10 Lectures on the HISTORY OF ARCHL 

TLCTUKAL DICXliLOPMlCNT, by I'lol. F. M. 

SniHsoN. Commencing April 2jnd, 11 a.m. 
Introductory Course of 12 Lectures on IDICALISTIC 

ETHICS, i)y Rrof. G. n.wvts Hu ks, M.A., Ph.D. 

Tuesdays and Thursdays, 5 p.m. Commencing 

April 26tli. 
Course of liight Lectures on POST-ARISToTELl AN 

PHILOSOPHY, by Prof. G. JXwves Hicks, M.A., 

Ph.U. Tuesdays, 4 p.m. Commencing May 3rd. 

,/*^ •'^ ^^ "^^ -^^ 

Recent Patents. 



FIG. 3 



d' 



Oy 



b 



I9,6s2. Electricity, measuring. Naluek, F. II., and 
-Xaldek linos, AND Tumnsox, i-\, yueen Street, London. 
Sept. s. 

Currtnl Meiers. — An am- 
meter or volt-meter, having 
a soft-iron needle movable 
about an axis at right- 
angles to the magnetic axis 
of a coil .;, is provided with 
a magnetic shield h, //* of 
soft iron or mild steel, 
which may be enclosed in 
an ordinary cast-iron cas- 
ing. The shield has the 

form of a cubical box surrounding the coil, its ends being open. It 

may be in two parts, as shown, one overlapping the other tightly. 

Or it may be in one piece, the ends of which are overlapped. 

23. 73'- Variable=speed mechanism. Mhisckkk Smith, W, 
and Mkisciikk-S.mhii, (i V . lioth nf 7, Kiie DruucM, I'aris. 
Oct. JO 

KL-latoi to variable-speed mechanism, 
particularly for use with motorcars and in 
connection with friction-ratclietdriving-ap- 
paratus, such as isdescribed in Specification 
No. 20,135, A.D, igo2. A crank « mounted 
on a shaft c has the crank-pin /( mounted on 
anut/, wliich can move on ascrew/Mn the 
crank ii for producing a variable throw. The 
screw /( terminates in a worm-wheel I, 
which gears with the worm c on a sliort 
shaft carrying a pinion d. The piniun d 
engages with both a loose toothed wlieel/, 
and a loose inner toothed ring g. The 
wheel / is fixed to the disc w so that either 
/org can be retarded by a brake. When 
either is retarded, the piiiicjii d is caused 
to rotate, and, througli it, the screw A and 
the nut i relatively to the crank u. 




102 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 



33.733- Photography. 

Oct. 30. 



Beck, C, 68, Cornhill, London 




Ciimciiis : rallir slidt's : sJiullcis. — Relates to a camera with roller 
slide and two shutters, one at the focal plane and one at the lense. 
The camera is shown in Fig. i, with the bellows removed The 
rollers 12, 11 of the bUnd shutter are mounted between rollers i of 
the roller slide. The front 3 is mounted on metal runners 5 fixed in 
the middle of the hinged base-board 7. To fold up the camera, the 
front 3 is pushed back, the stays 6 are disconnected, and the base- 
board 7 is folded up on the back. The camera is supported by a 
metal frame 8, which is pivoted to a base-board 7 so that it can be 
turned over the end of the latter in folding up the camera. The 
focussing is done by moving an arrow on the front along a scale of 
distances on the base-board, lines being marked on each side of the 
arrow to indicate depths of focus for tlie different lense apertures. 
The lense shutter, which consists of two hinged plates 15. is closed 
while the roller bhnd shutter is being set by turning the button 25. 
To make an e.xposure, the button lO is depressed, a movement 
which, acting through the links 17, 18, 20, or through a ffe.xible 
shaft, opens the shutter 15, then lifts the pawl 14, which releases the 
roller blind shutter, and makes an e.xposure. The blind shutter has 
two apertures, one equal in size to the aperture 2 in the back of the 
camera, and a narrower aperture for more rapid exposures. There 
is an adjustable stop arrangement in the blind roller 12 liy means of 
which either of these apertures can be used This stop arrange- 
ment consists of an axial screw actuated by the roller 12 and thus 
moved lengthwise, till it comes against a stop and arrests the 
shutter. For a time exposure, the large aperture of the roller blind 
is brought opposite the opening 2 and held there by the pawl 14, 
which is locked by a sliding plate 81 The time e.xposure is then 
made by the front lense. A method of holding the spools of roller 
slides so that they can be easily removed or inserted is described 
A spring is placed at one end of the spool so that it can be pushed 
back to liberate the other end. 



23,858. Therino=electric batteries. Johnson, J Y , 47, 
Lincoln's Inn hields. London — (ir,i//'i~ Co., A.: Bli-ii-lnlnissf, 
Fianhfi'it-on-tke-Muiii. Ccimnny). Oct. 31. 



FIG. I 




Consists in the employment of special 
shaped bars for use in a thermo-electric 
battery. The bar 6, consisting of a 
nickel-copper alloy, is bent as shown and 
has a barr cast on one end, this bar being 
an antimony-zinc alloy to which iron or 
cobalt has been added, in order to raise 
its melting point and to increase its 
mechanical strength. A copper strip;/ is 
attached to the nickel at its cold end, to 
act both as a support for, and to facilitate 
the cooling of. the nickel, whilst a copper 
plate is attached to the antimony for the 
same purpose. The short horizontal and 
vertical arms of nickel, which are heated 
to produce the thermo-electric current, 
may be replaced by silver, or an alloy of 
copper and silver, or copper coated with 
silver or gold ; or the short horizontal 
arm alone may be so replaced. 



12, Kaiserstrasse, Nurem- 




9, 749. Photography. Beck, F 

berg, Germany. Sept. 9. 
Ciimeni s^i;«?s.— Relates to a supporting-device for hand cameras, 
which is detachable from the 
camera. It consists of a base- 
board in two parts ii; b hinged at c. 
At the back of the part j is pivoted 
a bracket d having a sliding bar e 
with an arm /, which is pressed 
down on the camera back g and 
7 Jll LU '- ^i' ! ! J ' L clamped by the lever /;. The 

'i i, ^ nXlXP'^^J front / of the camera is held by a 

spring clip which is pivoted to the 
front of the part h. When the sup- 
port is not in use, the brackets d. i 
are folded down flat, and the parts 
I', b are folded together on the 
hinge r. The camera may be laid 
on its side on the support, when the front I rests on the block m, 
and the arm / is pushed further down. 

23,969. Arc light projectors. 

Engelsmann, a., II, Armin- 
strasse, Stuttgart, Wiirtem- 
berg, Germany. Nov. 3. 
Rijii-cters for projecting light 
from alternating-current arc 
lamps The light from the car- 
bons />, I" is reflected by two 
annular parabolic mirrors d, f, 
that falling on the mirror /being 
reflected again by an annular mir- 
ror 4', within the mirror <l. 




N-Rays 



Stored up by 
Bodies. 



Certain 



III the course of hi.s investigations of the N-rays, Professor 
Blondlot, as pointed out in a note just read before the French 
Academy of Sciences, happened to state an interesting phe- 
nomenon. N-rays being produced by an Auer burner enclosed 
in a lantern, would traverse first one of the walls formed by an 
aluminium foil, to be concentrated afterwards by a quartz 
lease on phosphorescent calcium sulphide. The Auer burner 
ha\ing been extinguished and taken away, the phosphorescence 
would persist with nearly all its brilliancy, and on interposing 
a lead screen or moistened paper or else the hand between the 
lantern and the sulphide, the latter would be darkened ; 
nothing was thus changed by the Auer burner being taken 
away but for a gradual decrease in the strength of the effect 
observed. Twenty minutes afterwards, they would still per- 
sist though being nearly insensible. 

On closer investigating, the conditions of this surprising 
phenomenon, Blondlot soon noticed that the quartz lense had 
itself become a source of N-rays; as, in fact, this lense was 
taken away any action on the sulphide would disappear, 
whereas by approaching the lense, the sulphide was made to 
take a higher brilliancy. The author then exposed a quartz 
plate 15 mm. in thickness, the surface of which was a square 
of 5 sq. cm. to tlie action of N-rays given oft" from an Auer 
burner through two aluminium foils and black paper, when the 
plate would become active like the lense ; as, in fact, the sul- 
phide was approached, a phenomenon would be observed as 
if a darkening veil were taken away from it. In all these 
experiments the secondary emission from the quartz adds its 
effect to the N-rays directly emanating from the source. This 
secondary emission resides throughout the mass of the quartz, 
and not only on its surface, as by placing successively several 
quartz plates one on another, the effect is found to augment 
with each added plate. Islandspar, fluorspar, glass, &c., 
show a similar behaviour. A Nernst lamp filament will remain 
active for several hours after the lamp has been extinguished. 
A gold piece, on being laterally approached to the sulphide, 
subinitted to the action of N-rays, would take a higher bril- 
liancy ; lead, platinum, silver, zinc, &.C., would produce the 



May, 1904.] 



KXOWT.F.DGE \- SCIENTIFIC NEWS. 



103 



same effects. These actions would persist after the extinction 
of the N-rays. as in the case of quartz, though the property of 
emitting secondary rays does not penetrate liut slowly the 
m.asses of metal. 

Aluminium, wood, dry and moistened paper, paraffin, &c.. do 
not show this' property of storing up Nrays. Calcium sul- 
phide, on the other hand, will exhibit the same effect. This 
phenomenon accounts for the fact formerly observed by the 
author that the increase in phosphorescence under the action 
of N-rays require a cert.ain time both to be produced and to 
disappear. .-Vs. in fact, N'-rays .are stored up, the different 
parts of the mass of sulphide 'will mutually strengthen their 
phosphorescence; as. however, the storing up is progressive, 
and as, on the other hand, the amount .stored up is not 
e.xhausted instantaneously, the effect of N-rays falling on 
phosphorescent sulphide must increase slowly, .and on being 



cords of two brothers, dead of hereditary ataxia. Coloured 
plates illustrate the lesions of the spin.al cord. 

The article in question is extremely interesting to neuro- 
logists and medical men, and should be studied by those 
seeking the truths of well-deep neurological liter.ature. 

To the gener.al scientific reader, who does not wish for 
technical details, the .article brings home the lessons of care 
that parents should take in inquiring into the antecedents of 
those about to m.arry. 

Dr. Sanger Brown says, and truly says : '• Hereditary ataxia 
is a disease which may be traced through several — at least 
four — generations, increasing in extent and intensity as it 
descends, tending to occur earlier in life, .and to advance more 
rapidly. It usually attacks several members of the same 
family. It occurs most frequently between the .ages of 16 and 
35. It shows no marked preference for sex. but it descends 




eliminated their effect cannot but progressively be extin- 
guished.' 'Certain stones picked up in a court where they had 
been exposed to the action of sun rays in the afternoon would 
give off spontaneously N-rays. preserving this activity for four 
days without any appreciable decrease. The surface of these 
bodies should, however, be very dry, the slightest layer of 
water being sufficient to stop the N-rays. 



Hereditary Ataxia. 



Among the latest volumes of the Decennial Publications of 
the University of Chicago is an interesting article by 
Lewellys F. Barker,* which includes a detailed description of 
the gross and microscopic findings in the brains and spinal 

'"A Description of the Brains and Spinal Cords of Two Brothers, 
Dead of Hereditary Ataxia of the Series in the Family Described by 
Dr. Sanger Brown," by lewellys F Barker. 'The Decennial 
Publications of the University of Chicago. 



Family Tree of Hereditary Ataxy. 



through females four times as frequently as through males 
There is always considerable inco-ordination of all the volun- 
tary muscles, and a sluggishness of the movements which they 
produce, when the disease is well established. This is 
usually noticed first in the muscles of the legs, but in a few 
months or years extends to the arms, face, eyes, head and 
organs of speech. Sometimes it occurs first in the upper 
extremities, and sometimes in the organs of speech." 

There is little to be noticed in the macroscopic appearance 
of the cord as shown in the illustrations given, but micro- 
scopically, there is revealed marked degeneration in the grey 
and white matter. 

The matter contained in this publication is accurate, and 
shows a profound insight and knowledge of the disease treated. 
By its study, we are enal)led to know with certainty the 
neurone-systems principally involved in the individuals who 
are affected, though we are as yet entirely ignorant as to why 
just these neurone-systems should be picked out. The letter- 
press is clear and large, and the plates are extremely well 
done. We must congratulate the University of Chicago Press 
Illinois, on the first series of their publications for the 
University of that city. — S.G.M. 



I04 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May, 1904. 




Conducted hy F. Shili.ington Scales, f.r.m. 



MITES. 



Cecil \\'ARBrRTOx, M.A. 
Why do so few people collect mites ? If we come to think 
of it the waste of energy among collectors is appalling, 
simply because nearly all are content to follow beaten 
tracks, where the chances of new discoveries are rare, 
and the same old observation is made for the fifty- 
thousandth time. There must be hundreds of people in 
England at this moment whose hobby is the microscope, 
who are skilful in the manipulation of small objects, and 
possess the collector's instinct, but whose imagination 
does not get beyond making neat preparations of dia- 
toms or rotifers, or Foraminifera. And all the time here 
is a group of creatures ideal for the purpose, of great 
intrinsic interest, and concerning which a great deal 
remains to be discovered. Anyone who attacks the 
Acari with enthusiasm is pretty sure to add not one but 
many mites to the sum of human knowledge. 

Many, no doubt, are deterred by the very fact that so 
little is known about these creatures. A moth, or a 
beetle, or a rotifer can generally be identified wath com- 
parative ease, because the researches of innumerable 
workers in these groups have been reduced to a form 
convenient for reference ; but how is one to identify a 
mite ? There is force in this argument, of course, though 
if the difficulties are greater, the chances of distinction 
are greater in proportion. In one family of the Acari, 
the Oribatida- or " beetle-mites," moreover, this difficulty 
does not exist. Just consider, for a moment, the follow- 
ing facts. 

Hardly a single Oribatid mite was recorded as having 
been captured in this country before 1879. In that year 
Mr. A. D. Michael published the first of a series of 
papers on these creatures, which he has since summed 
up in an admirable monograph,'' fully illustrated, and 
containing every kind of information which can be of 
use to the collector. In this about a hundred British 
species are described. Remember that he was absolutely 
a pioneer in the subject, and worked at it almost single- 
handed in the leisure hours of five years of a busy pro- 
fessional life, and that very little indeed has been done 
since. He has given his followers a magnificent start : 
but is it likely that the mine he discovered and worked 
so enthusiastically is anywhere near exhaustion ? 

It would appear at first sight that the search for 
creatures which seldom e.xceed a millimetre in length, 
and are frequently very much less, must be laborious 
and irksome. The exact opposite is the case. Cer- 
tainly it would be out of the question to go out into the 
open, armed with a lens, in search of individual mites, but 
there is not the least need for such a proceeding. These 
mites live under loose bark, in decaying wood, and 
especially in lichen and moss. The necessary equip- 
ment, then, for field work is not a lens at all, but a bag, 
or several bags. Thus armed the collector starts out to 
visit some likely spot that has occurred to him, a moss- 
grown wall, or a coppice where the trees are grey with 

• Publications of the Royal Society, 2 vols. 



lichen, and the ground carpeted here and there with 
patches of moss, and with such materials he fills his 
bags, bringing them home to work over at leisure. 

The study or "den" is now cleared for action. The 
apparatus consists of a pocket-lens, some large sheets of 
white paper (the white under-surface of remnants of 
wall paper is excellent for the purpose), a camel's hair 
brush, some ordinary microscope slides, and a low-power 
microscope arranged for opaque objects. I know of 
nothing better for the work in hand than a Stephenson's 
binocular with the one-inch objective. Portions of the 
moss are shaken out over the paper, and the dihris 
allowed to remain undisturbed for a minute or so. Then 
most of the creatures shaken out of the moss will have 
found their feet, and will not be dislodged if the general 
litter is gently tilted off or blown aside. Numerous little 
specks are sure to be left adhering to the paper, and a 
moment's observation will show that some of them are 
slowly moving. Then the lens is brought into play, 
and the moving speck examined, and if it seems to be 
one of the creatures sought, it is transferred to a slide by 
means of the brush, and placed under the microscope for 
a closer study. But there are many other moving 
specks, and time is too precious just now to spend more 
than a moment or two o\er a single example, so w'e 
lightly place a cover-slip on his back, and thus loaded he 
is not likely to have moved \ery far when we ha\'e 
leisure to look at him again. 

If the material is good, the hunt will be found exciting 
enough while it lasts, and the '• bag " will be a certain 
number of tiny creatures making ineffectual efforts to 
walk along on the slippery surface of the glass slides 
under the superincumbent weight of the cover-slips. 
What is to be done with them ? Well, the more 
thoroughly they can be examined while alive, the better, 
but those that are selected for the cabinet have to be 
killed and preserved in some way or other. In a 
collection of mites it is very desirable to have a double 
series of specimens, one series mounted as opaque 
objects, and the other rendered transparent. Whichever 
their destination, the preliminary operations are the same. 
The best w'ay to kill them is to pop them into boiling- 
water. It sounds brutal, but it is instantaneous, and it 
has the advantage that it causes many species to extend 
their legs, and those that are not so obliging are generally 
in a more or less limp condition, and pretty easily mani- 
pulated. Now is the moment when the skill of the 
operator comes in. The mites are taken out of the 
water with the brush, and placed on white blotting 
paper. Then a single specimen is placed on a slide, 
turned on his back, and his legs arranged in the desired 
attitude under a dissecting microscope. A cover-slip 
keeps him in the proper position, and a drop of 2";', 
solution of formalin is run in, a slight weight, such as a 
flattened shot, being superimposed to prevent the legs 
from curling up again. For the even distribution of the 
weight it is well to make a tripod with three specimens 
and the cover-slip. 

Next day the creatures will be found to be rigid, and 
ready for dry mounting. If they are to be made trans- 
parent, carbolic acid is substituted for the formalin, 
which is remo\ed by means of blotting paper as the 
acid is added. Some species will require a very much 
longer time in the carbolic acid than others, but they 
simply remain in till clear, when they are ready for 
mounting in Canada balsam, and the collector then has 
one specimen which shows how the animal looks when 
alive, and another in which minute points of the exter- 
nal anatomy may be studied. In this particular group 
of mites the chitinous cuticle is generally well-developed, 



May, 



1904., 



KNOWLEDGE Ov; SCIHXTIFIC XEWS. 



I "5 



and the creatures lend th(>msolvi'> excellently to dry 
mounting. 

\'ery wet moss will not yield up its inhabitants on 
shaking, and it must be somewhat dried — not too rapidly. 
If there is a great deal of coarse ih'hn's, as is sometimes 
the case, there is a danger of all the mites being swept 
off as the paper is tilted, and to obviate this it is not a 
bad plan to use some wide-meshed muslin as a sifter. 
The mites and the smaller particles of earth readily 
pass through the meshes, and can be distributed exenly 
over the surface of the paper with better chances of 
successful hunting. 

(7V be continued.) 

Royal Microscopical Society. 

March 16.— Dr. Diikinfield H. Scott. F.R.S.. President, in 
the chair. Prof. .\. K. Wright communicated the purport of 
his paper " On Some New Methods of Measuring the Magni- 
fying Power of the Microscope and nf Lenses Generally." He 
described also the piece of apparatus which he had invented 
for taking the magnifyiug power of the microscope and for the 
rapid measurement of microscopic objects, which he termed 
an Eikonometer. It is placed over the eyepiece, without dis- 
turbing any of the adjustments of the instrument, and the 
object on the stage can then be instantaneously measured. 
The Secretary read a short note by ^fr. I£. H. Stringer "On 
the Separation of L"ltra-\'iolet Light." Mr. .\braham Flatters 
exhibited on the screen a series of 60 hand-painted lantern 
slides illustrating botanical histology. The slides were photo- 
micrographs of the actual micro-sections coloured accuratelv 
to represent the staining, and were much commended. 



Queckett Microscopical Club. 

The 412th ordinary meeting of the Club was held on 
March iS, at 20. Hanover Square, \V., the new President, 
Dr. Edmund J. .Spitta. V'.P.K.A.S., in the chair. The Secre- 
tary announced that the new catalogue of the Club's Library, 
containing some 1300 volumes, had been published, and was 
on sale at the price of one shilling. 

Mr. T. G. Kingsford exhibited and described some glass tanks 
which he had constructed by a new method which did not 
involve the use of cement. These were primarily intended 
for use as light filters or screens, but they were also adapted 
for examination of pond life. The sides were formed of glass 
discs (clock glasses) kept at the desired distance by blocks of 
.rubber cemented to a rubber band. This rubber band formed 
a lining to a similar l)aud of flexible metal, the ends of which 
were drawn together by a screw. The pressure of the baud 
upon the edge of the discs made a water-tight joint. 

The Secretary read a note on the resolution of Amphiphuva 
pellucida, by Lieut. -Col. John Thompson, of Brisbane. 

Mr. D. J. Scourfield read a note, communicated by Dr. 
Vavra, on two Phyllopods from Bohemia, describing the life- 
history of these curious Entomostraca. 

The Secretary then read extracts from a highly-technical 
paper by Mr. T. B. Kosseter, F.R.NLS., "On the Genitalia of 
Taenia Sinuosa," the remainder of the paper being taken as 
read. 

Ne^v Achromatic Condenser. 

Messrs. J. Swift and Son have sent me for critical exai7iina- 
tion a new achroniatic condenser of the form which is now 
rapidly superseding the ordinary non-achromatic type, which 




has so small an aplanatic cone as to be nearly useless for really 
critical work. Messrs. Swifts condenser is achromatic, its 
power is ,'„ of an inch, and its aplanatic cone is between 95 
and -96, with a numerical aperture of i. With the top lens 
removed the power is about ij inch, but the" aplanatic aper- 
ture, as always happens under such circumstances, suffers 



.accordingly. dro]iping to -4. The back lens is nearly i inch in dia- 
meter. It is notgencrallyrealiscdtliattoobtainthe full aplanatic 
aperture of condensers of so perfect a type a definite thick- 
ness of slide must be used, and t" obviate this and .it the 
same time enable the best results to be arrived at, Messrs. 
Swift fit an improved form of correction collar to enal)le the 
necessary adjustments to be made. Theprice of the condenser, 
without mount, is 4.SS., and the correction collar is 15s. extra. , 



Notes and Queries. 

I am glad to be able to announce with the present number the 
resumption of the " Notes and Ouerics " column, which, owing 
to circumstances beyond my control, but incident to the pres- 
sure of other matter in the colunmsof this journal, has hitherto 
been held over. In this cohnnn I shall endeavour, ,is hereto- 
fore, to answer (as far as I am able) all (jnestions addressed 
to me which are of general interest. I wish also, if possible, 
to give an opportunity to my readers to publish short notes 
on matters appertaining to microscopy, which may interest 
them, or on which they may desire to interchange views, 
though, of course, limitations of space will necessitate my 
exercising a personal discretion in such matters. On many 
occasions, bv the kindness of various correspondents, my 
predecessor. Mr. Cross, and 1 have also been able to distribute 
micro-material to applicants, and I ho]ie that any readers who 
may have material of this sort suitable for distribution will 
give their assistance in this respect. 

Magnification of Objectives and l;\epieces. (Major C. W. 
Ta ruAM, I")(voiipor).) 

A ,', -inch objective professes to give an initial magnifica- 
tion (without eyepiece) of 120 diameters with a lo-inch tiihe. 
If it is corrected for and used with a shorter tube it will give a 
proportionately lower magnification, i'./,'.. with a 6-inch tube 
the initial magnilication will be -,'v-ths of the foregoing, i.e., 72 
diameters. This magnification is increased by that of the eye- 
piece, which is, of course, itself unchanged, whatever the tube- 
length. Thus a -/.-inch objective used with an eyepiece that 
has itself a magnifying power of 5 will give with a lo-inch tube 
120 X 5 = 600 diameters. With a 6-inch tube the total mag- 
nification will be 120 X — X 5 = 360 diameters. Now come 
10 

in two qualifications: First, that the objective is never quite 
in accordance with its professed magnification (based on the 
equivalent focal length), and is generally considerably higher 
second, th.at the oculars ;ils<i are not what they profess to be, 
and, moreover, that many makers will persist in rating them as 
if they and not the objectives varied in power according to 
variation in tube-length. For instance, your compensating 
eyepiece 12 may not be 12, but about half as nuich again, 
Zeiss assuming that tlie /.^-inch gives 120 magnifications at 
6.^^ inches, and that this is multiplied by a 12 ocular, making a 
total of 1440 diameters, whereas, as a m,atter of fact, with this 
tube length, the 1440 diameters is made up of objective mag- 
nification 72 X ocular magnification 20 or therealiouts! The 
compensating eyepieces for the long tube are therefore marked 
with their proper magnifications, and those for the short tube 
are the same oculars marked down .as if they were 6j times 
what they really are. With regard to testing the magnifica- 
tions of objectives and oculars yoiuself, you will find detailed 
instructions in my article in the I'ebruary issue. If you do 
not follow any point write to me again. Meanwhile, I need 
scarcely say that any power ocular can be used with any 
objective, provided the fatter will bear it. 
Mounting Diatoms in (ium Styrax and Monobromide of Naph- 
thalene. (G, \. F.VANS, P.ristol.) 

I think you will find all that is necessary for mounting 
diatoms in these highly-refractive media in Carpenter, page 521 
(8th edition): The gum styrax can be dissolved in benxole or 
xylol ;ind used as Canada balsam is used, save that more care 
must be taken to evaporate the benzole, or other solvent, 
before covering with the cover-glass. Monobromide of n.iph- 
thalene is solulile in alcohol and ether, but in Carpenter it is 
recommended that the mount should be run round with a ring 
of wax, then ringed with Heller's porcelain cement (which is 
not familiar to nie), and finally closed with shellac. 



[Communications and enquiries on Microscopical matters are invited, 
and should he addressed to F. Shillinglon Scales, "Jersey," SI, 
Barnabas Road, Cambridge.'] 



io6 



KNOWLEDGE & SCIENTIFIC NEWS. 



[May 1904. 



The Face of the Sky for 
May. 

By W. Shackleton, F.R.A.S. 



The Su.n'. — On the ist the Sun rises at 4.35, and sets 
at 7.20; on the 31st he rises at 3.52, and sets at 8.4. 

Sunspots and facuhe should be looked for whenever- it 
is fine ; the positions of the spots with respect to the 
equator and pole may be derived from the following 
table :— 



Dale. 


.\Nis inclined to W. from 
N. point. 


Centre of disc, S of 
Sun's equator. 


May I . . 

10 . . 

20 . . 

,, 30 .. 


24' 16' 
22° 22' 

19° 36' 
16= It' 


3° 58' 
3° 0' 
1^52' 
0" 4 1 ' 



The Moo.\ : — 



Date. Phases. 


H. M. 


May 7 .. 

.. 15 ■• 

22 .. 

,. 2g .. 


'Z Last Quarter 
• New Moon 
'1 First Quarter 
G Full Moon 


II 50 a.m. 

10 58 a.m. 

10 ig a.m. 

8 55 a.m. 



May 8 .. 
22 . . 



.\pogee 
Perigee 



4 18 p.m. 
10 30 p.m. 



Occulta-tions. 

There are only two occultations of fairly bright stars 
observable at convenient hours during the whole month. 
The particulars are as follows : — 



Date. 


Star's Name. 


.Magnitude ^''-PP- ^^-PPf- 


May 17 
,, 21 


130 Tduri 
Leon is 


55 7.27 p m. 8,20 p.m. 
38 9. I p m. g 26 p m. 



The Planets. — Mercury will be observable for the 
first four or five days of the month ; he should be looked 
for in the N.N.W. immediately after sunset at about an 
altitude of 15". He is bright enough to be visible to the 
naked eye, but any slight optical aid will be of great 
assistance in detecting him in the strong twilight. The 
planet moves so rapidly that he is in inferior conjunction 
with the sun on the 13th. 

\'enus is a morning star throughout the month, rising 
only a short time in advance of tlie sun, and being for all 
practical purposes unobservable. 

Mars is in conjunction with the sun on the 30th, and 
is therefore out of range. 

Pallas is in opposition on the i6th, when the magni- 
tude is 8-5. On this date, the minor planet has the same 
R..\. as 7 Herculis, but is situated 6" north of the star. 

Jupiter is a morning star, rising about 3 a.m. 

Saturn is also a morning star, rising about 1.20 a.m. 
near the middle of the month ; he is in quadrature with 
the sun on the nth. 



Uranus rises about 11.30 p.m. near the beginning of 
the month, and about g.30 p.m. towards the end of the 
month. The planet is situated 4 mins. E. of 4 Sagittarii, 
and, observing with a low power eyepiece, can be seen 
in the same field of view as the star. 

Neptune sets too soon for observation. 

Meteors. — The principal shower during May is the 
Aqnarids. This maybe looked for between May i-6; 
the radiant being in R.A. 22 h. 32 m., Dec. S. 2°., near 
the star -n Aquarii. 

The Stars. — About 10 p.m. at the middle of the month 
the followdng constellations may be observed : 

Zemth . Ursa ^lajor. 

North . Polaris ; to the right, Draco and Cepheus ; 
below, Cassiopeia ; Perseus to the left. 

South . I-]o6tes and \'irgo, Avcturus and Spica a 
little E. of the meridian ; Leo to the S.W. 

West . Gemini and Cancer ; Taurus to N.W. ; 
and Procyon to S.W. 

East . Lyra (Vega), Corona, Hercules, and 

Ophiuchus ; Cygnus to N.E.,and Scorpio in S.E. 

Telescopic Objects: — 

Double Stars: — ^ Libra?, XI\'.'' 46™, S. 15- 39', mags. 
3, 6 ; separation 230" ; very wide pair. 

ff Coronae, XVI.'' ii"", N. 34° 7', mags. 6, 61; separa- 
tion 4"'4 ; binary. 

a Herculis, XX'II.'' lo", N. 14° 30, mags. 2i, 6; 
separation 4"-q. \'ery pretty double, with good contrast 
of colours, the brighter component being orange, the 
other blue. 

{Herculis XX'H.^ 11™, N. 24° 57 , mags. 3, 8; separa- 
tion 17". 

Clusters. — M13 (cluster in Hercules) situated about 
J the distance from t) to '( Herculis, and is just visible to 
the naked eye. It is a globular cluster, and with a 3 or 
4-inch telescope the outlymg parts of the cluster can 
be resolved intu a conglomeration of stars. 

•'^i ^*^ ^'^ ^*i ^^ 

Brass Stripping. 



Electrolysis, which deposits surface films of metal, has lately 
been put to an ingenious industrial use in stripping metals. 
Professor C. F. Burgess records a method of stripping super- 
fluous brass from the joints of bicycle frames by using an elec- 
tric current with a solution of sodium nitrate. The firm which 
has adopted the method used to make use of hand lalionr. 
which damaged the tubes, and afterwards of chemicals, such 
as potassium cyanide, which were expensive and slow. By 
this reversal of the principle of electrolytic deposition the brass 
can be cleaned off the tube joints in from five to forty-five 
minutes at a scarcely appreciable cost. 

Calcium as arv Industrial Metal. 



Pkoff.ssor Borchers, of Aix-la-Chapelle, has succeeded, after 
overcoming many difficulties, in producing calcium by a new 
electrolytic process, by which, it is said, the metal can be ob- 
tained at a very low cost. It is now being extracted on a 
large scale, and there should be a great future before it, for, 
while of very common occurrence, calcium possesses certain 
properties, such as a great affinityfor oxygen.which should make 
It a very desirable innovation in the iron industries. Exposed to 
moist air the metal rapidly becomes coated with oxide ; but it 
nevertheless possesses many characteristics which may prove 
of value in the arts. It is fairly hard (harder than lead), can 
be hammered into leaf, and is very light, having a specific 
gravity of only 1-58, or much less than that of aluminium 



KDomledge & Selentifie Neuis 

A AlOXTllLY JOURNAL Ul- SCILiNCE. 



Vol. I, No. 



[new series.] 



JUNE, 1904. 



r Entered at 
LStationers' Hall 



] 



SIXPICNC 



Contents and IS'otices. — See Rage VII. 

RoLdio-Activity acrvd 
R^aLdium. 



By W. A. SiiKNSTONE, I'.R.S. 



II. 



The discovery that radium gives ofT, unceasin'^ly, the 
radiations discussed a little later, and the early observa- 
tion that in many respects these resemble the Kiintgen 
or X-rays naturally suggested that possibly a few 
milligrams of radium miglit ad\antageously replace the 
comparativelj' complicated equipment required for the 
so-called X-ray photography, and accordingly this very 
interesting side of the subject has excited some interest. 
Whether radium rays will ever replace the usual 
apparatus for the production of Rontgen rays remains to 
be seen. But some very interesting results have un- 
doubtedly been obtained, as my readers will gather from 
the following series of very excellent radumi radio- 
graphs which I am allowed to introduce by the kind 
permission of Mrs. Gifford, of Chard, who has been 
working on this subject with great success. The con- 
ditions are given under each plate. Fifty milligrams of 
highly-purified radium bromide in glass tubes were used. 




Fig 6 — The radium salt was enclosed in two light bags. Exposure, 
24 hours, at a distance of 9-65 cm. Medium plate. Most of the 
objects will explain themselves. The rectangular figures at the 
top are produced by blocks of glass, that to the right by ura- 
nium glass The crystal near the larger block was fluor spar, 
the amorphous mass at the bottom on the reader's right is Kauri 
gum. 



The trouble which arises in regard to the use of radium 
salts for work of this kind, 1 am informed, is this : Thai 
it is diflicult, if not impossible, to concentrate the acting 
salt into a sufficiently small space. The radiations 
used, in short, are too din'use. 




Fir,. 7. — Taken under much the same conditions as 6, but througli 
a plate of aluminium and with a 10 hours' exposure. 

The distinctive characters of radium which were first 
recognised were what are commonly known as " its 
radiations." But almost more wonderful and mysterious 
than these is the " emanation," which has been .so 
carefully studied by Professor Rutherford, of Montreal. 

The Radiations of Radium. — These have been classified 
as a, /3, and y ray.';. The last resemble Riintgen rays. 
They are unaffected by a magnetic field, and are intensely 
penetrative, passing through sheets of lead of consider- 
able thickness, and these rays alone of the radium rays 
can penetrate the eyelids freely, so that they can be 
identified by the sense of diffuse light, of which one 
becomes conscious when a few milligrams of a radium 
salt are held near the tightly closed eye in a dark room. 

One of the greatest achievements in physics during the 
latter half of the nineteenth century was the discovery, 
by Prof. J. J. Thomson, of Cambridge, and his colleagues, 
in the cathode stream of the Crookes* vacuum tube, 
of particles so small that about 700 of them would be 
required to produce a mass equal to that of an ;itom of 
hydrogen. These particles carry negative charges of 
electricity, and so are deflected by magnets; they will 
pass through thin sheets of metal, cause damp, dust-free 
air to form mist, and they make air conduct electricity. 
They move with a velocity equal to one-tenth that of 
light. They are often called " Electrons." * Now the 

• This terra was originally applied to the charge of electricity 

carried by an atom of hydrogen in electrolysis. 



io8 



KNOWLEDGE cV SCIENTIEIC NEWS. 



(■June, 1904. 



ji rays of radium exhibit just these properties, only 
they move even more rapidly, sometimes, indeed, 
several times as rapidly as the electrons in the cathode 
stream, and are more penetrative. Hence the ,3 rays 
may be considered to be " electrons." 

The a rays were the last discovered. These are far 
heavier than the others, and are very easily stopped. 




Fig. S- — Taken without bags, at a distance of 4 cm. and with 
5 hours' exposure. The dark shadow on the reader's left was 
produced by uranium : above it was a crystal of fluor spar 
The rectangle at the top was caused by glass, and the dark 
object below this was a threepenny bit. 

They can be deflected by powerful magnets, and the de- 
flection is in the opposite sense to that of the rays of the 
cathode stream, which shows they carry positive charges. 
Sir \\'illiam Crookes has shown us how to recognise 
them by letting them strike screens covered with phos- 
phorescent zinc sulphide, as in the " spinthariscope." 

Such substances as fluor-spar, kunzite, diamond, 
willemite, and barium platino-cyanide become luminous 




Fig. g. — .\ necklace of various jewels set in metal. No bag. Taken 
with a rapid plate in three and half hours at a distance of 44 cm 

if the rays of radium fall upon them, much as they do 
under the influence of cathode rays, the effects produced 
being exceedingly beautiful. 

The Emanation of Radium. — If radium be heated strongly, 
or if it be dissolved in water, a substance is given ofT which 
mixes with gases, and which, when freed from impurities, 
has the properties of a gas. This substance can be con- 
densed at the temperature uf liquid air in a glass tube, 
and is then phosphorescent. It can be re-evaporated. 



Its removal deprives the radium of 70 per cent, of its 
heating power, and the energy of the emanation is so 
great that it is calculated that if a whole cubic centimetre 
could be collected in one place it would probably melt the 
containing vessel. It is radio-active, and therefore must 
be supposed to be in a state of change, like radium. 

The transformation of radium into its emanation and 
the connection between this change and the radio-active 
phenomena which accompany it have been investigated 
by Professor Rutherford. The phenomenon, as it appears 
to him, occurs in several successive stages. The heavy 
atoms — for radium has very heavy atoms — of radium dis- 
intregrate, throwing off positively charged particles, whose 
masses compare with those of hydrogen atoms, whilst 
new forms of matter lighter than radium remain behind, 
occluded as it were in the remaining radium. These re- 
sidues are also radio-active and undergo further change of 
a similar kind stage after stage until at last a, ,if, and 7 rays 
are all expelled. 

Professor Rutherford suggested on certain grounds that 
probably helium would be found among the products of the 
disintegration of radium, which led Sir William Ramsay 
ind Mr. Soddy to seek it. They find that though the 




FiG. 10.— No bag was used in this case Rapid plate. Distance 
44 cm. Time of exposure, two hours. 

emanation of radium when first liberated by dissolving a 
radium salt in water contains no helium, yet this element 
may be detected in the same emanation after a few days. 
For the present, therefore, we regard helium as the ulti- 
mate product of the disintegration of radium, or at least 
as the only such product yet detected. 

The discovery of radium and of its unique properties 
raises some important questions : — 

I. — Whence does radium derive its vast supply of 
energy ? It has been suggested by some that it acts as 
a transformer, picking up energy in some way from its 
environment and giving it out again as light, heat. Sec, 
in the course of its disintegration. Another school (and 
this predominates at present) regards radium as a 
form of matter endowed with relatively vast stores of 
potential energy ; and it has even been suggested, origi- 
nally, I believe, in order to compose certain differences 
between the physicists and the geologists on the subject 
of the age of the sun, that the energy of the sun would be 
accounted for by the presence of no more than three or 
four grams of radium in each cubic metre of its substance. 
Though, except such evidence as may be derived from 
the presence of helium in the sun, we have not much 
actual fact to support this latter hypothesis. 

One of the latest contributors to this most interesting 
problem is Lord Kelvin, who finds the second hypothesis 



JlNE, IQ04.T 



KX(n\i.]:n(;i' \- sciextific xr.ws. 



log 



difficult to accept, and pouits out that if two globular 
flasks, such as those in figure 12, one containing a 
black cloth A and the other a white one B be plunged in 
vessels of water and exposed to a source of radiant heat 
such as the sun, then the water in the vessel surrounding 
A will be hotter than that surrounding 1!, so long as the 
experiment is continued ; as may be proved by the 
pressure on the mercury at C, or by observing ther- 
mometers placed near A and B. 




Fig. II. — Time, eight and a half hours. Distance about 7 cm. 

Now the suggestion is that radium salts may absorb 
energy in this sort of way from some radiation in the sur- 
rounding ether, and that we know far too little as yet 
about radium and about the wave disturbances in the 
ether to dismiss this explanation of the mystery of radium 
from consideration before further experiments ha\e been 
made. 

2. — Is the production of helium from radium " a 
transmutation"; does it foreshadow similar transmutations 
among the better known and more plentiful elements, 
e.g., the transforming of lead into gold or vice versa ? 

It is, I fear, impossible to consider the question in this 
form seriously till we know much more al)out radium. 




On account of its spectrum, the character of its salts, 
and their general alliance with the calcium group, 
radium ranks as an element. Yet if we are exact we 
cannot truly say radium has never been decomposed, for we 
explain its most characteristic properties by supposing 
that every specimen of radium salt is disintegrating spon- 
taneously and resolving itself gradually into other formsof 
matter. Hence, it can hardly be regarded as an element 
in the sense in which oxygen is considered to be 
an element at this moment. The question before us, 
therefore, is this — Are the other elements radio-active 
like radium and its companions ? Do these also, 



though we do not yet recognise the fact, undergo 
similar transfornialions, only at a far slower rate ? 
If they do, or if we can prove that some of tiie 
lighter elements, c.;,'., oxygen, sulphur, or sodium, do so, 
then the whole ([uestion of the nature of the elements, the 
very basis of chemistry, must come up for revision. At 
present the position may be taken, provisionally, to be 
something of this kind. The elements may, for the 
moment, be di\ided into two classes. 

{a) Those which have relatively light atoms, and whicli 
are not, so far as we know at present, subject to 
disintegration, and are not radio-active, such elements, 
for example, as helium, oxygen, sodium. 

{!>) Tile radio active forms of matter such as radium, 
uranium, thorium, which exist in larger particles and 
exhibit many of the characters of the elements, but 
which disintegrate, throwing ofiF among their products 
atoms of elements of the more familiar type. 

Whatever the truth may be, and it seems likely we may 
long seek the answer to this big question, it is clear tliat 
the study of radio-active matter must greatly enlarge, 
iven if it does not re\olutionise, our ideas about the pro- 
. esses by which tlu: older and more familiar elements have 
iieen generated. 

The 

Structvire of Crystals. 

By H,\i;oi.i) 1 1 11. ton. 



It is proposed in this paper to give a brief account of the 
modern geometrical theory of crystal structure. The 
units of which a homogeneous medium is composed are 
called •' molecules " ; they are either chemical molecules 



•^ 



6 



V'Z. 1. 



9 



9 



J3 



no 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



or definite aggregates of these. The molecules of such a 
medium are either all of the same kind (of the same 
size, shape, iSrc.) ; or else they are half of one kind and 
half of another, the molecules of the two kinds being re- 
lated in the same way as a right-handed and a left-handed 
glove, that is, two molecules of different kinds may be 
placed so that they are reflections of each other m some 
plane. The two kinds of molecules are represented in 
the diagrams liy the letters p and q. The molecules of 
the medium are arranged according to certain laws of 
" symmetry," that is, every molecule of the medium 



through a distance t parallel to the axis ; (4) a reflexion 
in a plane called a " symmetry-plane " ; (5) a reflexion 
in a point called a " centre of symmetry " ; (6) a gliding 
reflexion, /.f., a reflexion in a plane (called a "gliding- 
plane ") followed by a translation parallel to the 
plane ; (7) a rotation through an angle a about a 
line followed by a reflexion in a plane perpendicular 
to the line. Each of these movements leaves un- 
altered the distance between two given molecules ; 
they may be considered as equivalent to only two 
distinct movements, (i) and (2) being particular cases of 












cr 



a 



a 



7 



/O 



/^ 



/> 



A 



yO 






















\? 




\) 




N) 




\? 


• 


"^ 


• 


cr 




« 


6 


• 


7 




9 






7 




7 




• 


CL 




O. 






CL 




/^ 




/> 






/C> 




c 


\) 





\) 




e 


\? 









cr 




cr 




• 


<r 


<^ 


« 


h 






A 




6 




9 




9 






9 





Fig. 2. 



(supposed of infinite extent in all directions) is brought 
by certain so-called "mo\'ements" into the position pre- 
viously occupied by some other molecule of the medium 
(the medium is said to be " brought to self-coincidence" 
by such a movement). These movements are of seven 
different kinds:— (i) a translation, i.e., a shifting of each 
point of the medium through the same distance in the 
same direction ; (2) a rotation through an angle o, 
about a straight line called a" rotation-axis" ; (3) a screw, 
i.f., a rotation through an angle a, about a straight 
line called a " screw-axis " followed by a translation 



(3) and (4), (5), and (6) of (7). The movements are 
illustrated by figure i in which the molecule i is brought 
into the positions now occupied by molecules 2, 4 by 
reflexion in the planes B, A (perpendicular to the plane 
of the paper) ; and into the position of molecule 3 by a 
gliding reflexion in B. The molecule 2 is brought into 
the position of molecule 3 by a translation, and of mole- 
cule 4 by a rotation through iSo" about the intersection 
of A and B. A medium may be brought to self- 
coincidence by an indefinite number of different move- 
ments, but the presence of certain symmetry-elements 



June, 1904.] 



KNOWLEDGE c^- SCIENTIFIC NEWS. 



1 1 1 



(i.f., rouii.. ;; .1^.;^, ... rew-axes, &c.) necessitates or pre- 
vents the existence of other elements. For example, if a 
medium is brought to self-coincidence by a gliding- 
reflexion in a plane, it must be also brought to self- 
coincidence by a translation parallel to that plane. It is 
assumed that every crystalline medium is brought to 
self-coincidence by three very small but linite translations 
not lying in the same plane — a fundamental hypotiicsis 
which is justified by remembering that the physical 
properties of a homogeneous crystalhne medium in a _i;inn 
direction are the same in every part of the medium. It 
follows from this assumption that the angle a. of move- 
ments (2), (3), (7) must be a multiple of 60 ' or of 90". It 
may be shown that the number of distinct arrangements 
of symmetry-elements is 230 — a geometrical problem 
solved independently by Fedorow, Schoenllies, and 
Barlow. One such arrangement is shown in figure 2. 
The system of molecules there given is supposed extended 
indefinitely in the plane of the diagram, and over and 
under it at distances 2/,, 4Z, 6z, . . . are placed 
similar and similarly situated systems so as to fill all 
space. It is evident that tlie collection of molecules so 
formed has the lines perpendicular to the plane of the 
paper, and passing through the points marked o and 9 
as rotation-axes (a = 120"), has the planes parallel t<j 
these axes, and passing through any two adjacent points 
marked O for symmetry-planes, and has the planes half- 
way between these symmetry-planes as gliding-planes. 
Such a collection of molecules is one of the six different 
geometrically possible ways of representing the structure 
of a medium (such as tourmaline, potassium bromate, 
&c.), which crystallizes in polyhcdra having a rotation- 
axis for which a = 120' and three symmetry- planes 
through that axis making angles of Go" with each other 
(and having no other symmetryelenient). 

Again, suppose that half-way between two neighbour- 
ing systems of molecules in the collection just described, 
we insert the system obtained by rotating figure 2 through 
180^ about one of the points marked O. The collection 
has the lines perpendicular to the plane of the diagram, 
and passing through the points marked • as rotation 
axes for which a = 120°, the lines perpendicular to the 
planes of the diagram, and passing through the points 
marked O as screw-axes for which a = Go" and t = z, 
and the lines half-way between any two adjacent rotation- 
axes as screw-axes, for which a = 180' and t = z. The 
collection has the same symmetry-planes and gliding- 
planes as in the previous case, and has also gliding-planes 
through the screw-axes perpendicular to the symmetry- 
planes. The collection is one of the four different 
geometrically possible ways of representing the structure 
of a medium (such as zincite, wurtzite, iodyrite, &c.), 
which crystallizes in polyhedra having a rotation-axis 
for which a = to' and six symmetry-planes through that 
axis making angles of 30'^ with each other. 

It must be remembered that it has not been proved 
that a collection of molecules, such as has been described, 
is one which can exist in stable equilibrium under the 
influence of the mutual attractions of the molecules. On 
the dynamical theory of crystal structure hardly any work 
has yet been done, but the geometrical theory is now 
fairly complete. 

Gkksham College Lectukes. — A course of lectures on 
"Recent Solar Researches" was delivered at Grosham Col- 
lege during Whitsun week by Mr. E. Walter Maunder, 
F.R.A.S. The subjects of the lectures, delivered on succes- 
sive evenings, were " Changes and Movements of Siinspots," 
" The Structure of Sunspots," " The Solar /Vtmosphere," and 
" Solar Periods and Influence." 



Aeroplane Experiments 
at the CrystOLl PoLlaLce. 

r>y Major liADiiN-l'oWKLL. 

Ir has often bee'ii supposed that one of the greatest 
difficulties to be overcome before successful aerial navi- 
gation can be achieved is the practical balance of the 
apparatus in mid air. Whether or not this will really 
prove a stumbling block it is impossible, with our present 
experience, to state with irertainty. Several inventors, 
it is true, have had considerable dillicultics in the initial 
starting of their machines, which have had a way of toppling 
over as soon as they ha\e been launched into the air. It 
seems just possible, however, that if the machine could 




Starting. 

be properly trinuned before starting, all such dilhculties 
might be overcome. We know that small models, if 
dropped from the hand or lightly thrown forward, will 
easily upset, if not properly balanced, but which, if the 
weights be carefully adjusted beforehand, will fly steadily 
enough on their downward course. But it is extremely 
difficult to calculate the position of the centres of gravity 
and of pressure, and practical trial is the only certain 
method of getting this balance, ilow, then, is it possible 
to test practically the balance of a machine which we are 
loth to launch into mid air because we are afraid of its 
toppling over ? 

With a parachute or surface dropping perpendicularly, 
the weight should, of course, be in the centre of area ; 
but if a more or less flat surface be progressing through the 
air horizontally, it is found that the centre of pressure ad- 
vances towards the front edge, and, therefore, if the weight 
be in the centre, the plane will rapidly rise in front, and will 
soon overbalance and shoot down backwards, liut the 
more rapidly the machine is travelling, the more does the 



112 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



centre of effort advance. It would, therefore, seem to be 
necessary to shift the balance in accordance with the 
speed. The anp;le presented by the aeroplane also causes 
this point to vary, so that experiments with the tilting of 
the aeroplanes are also necessary. 

It is often supposed that, in addition to what we may 
call the " passive " or " fixed " balance, we must take into 
account the action of the air currents on the wings. 
These may be the result both of the eddies caused by the 
progression of the planes through still air and of gusts of 
wind blowing against them. 

These actions and re-actions are little understood. 
Some authorities think that a large flying machine will 
be blown about like a piece of paper in the breeze, while 
others declare that a hea\ y machine progressing at a 



principal experimenters in this line have unfortunately 
lost their lives through some small deficiency in their 
apparatus, and if tried over land there is always the 
danger that any small mishap may result in the machine 
losing its balance and precipitating its operator to the 
ground. Such machines, at all events as hitherto de- 
signed, cannot well be tried over water for several obvious 
reasons. 

Moreover, such apparatus would usually progress com- 
paratively slowly. Now, to support itself in the air an 
aeroplane must move along at a very considerable speed, 
and the questions of balance and of steering are un- 
doubtedly much dependent on the rate of progress. 

One of the simplest means of giving an initial speed to 
any body is to cause it to run down an inclined track 





^■l^K-V^^^'^^-itfS&^ii^.. ..-«^I^K:.- 


»v5 ^^" 




i 



Aeroplane leaving the Track. 



speed far greater than that of the wind will scarcely be 
affected by it. 

Another problem calling for practical solution is that 
of steering. Vertical and horizontal rudders may seem 
a simple expedient, but it is doubtful if they form the 
most efficient means of steering. A bird has no vertical 
rudder, and tests with large gliding machines have 
pro\ed them to be not entirely satisfactory. 

It is therefore manifest that before we can build a 
proper airship we must make a series of trials with some 
apparatus progressing through the air and carrying an 
aeronaut to direct its course. Several experimenters have 
tried gliding machines, which have been designed either 
to soar down the face of a hill in the teeth of a wind, or 
to be drawn along by a string. But in addition to other 
drawbacks, these systems have the serious objection of 
being very dangerous to the operator. .Mrcady two of the 



and to shoot off into the air at the bottom. If means 
are adopted to pre\ent the machine from leaving the 
track before it gets to the bottom, and if it is then pro- 
jected over a sheet of water, there can be but little chance 
of a serious accident. 

I therefore decided, some months ago, to erect such a 
track, and conduct a series of experiments. Existing 
" water-chutes " at once suggested themselves as ready- 
made tracks, but, after examining several, and even making 
experiments with aeroplanes on them, I came to the con- 
clusion that such were not suitable to the purpose. They 
are not steep enough to get up sufficient speed, they are 
not sufficiently turned up at the bottom to shoot the 
apparatus off in a horizontal direction, and rails and lamp- 
posts interfere with large wings. Besides, it would be 
difficult to arrange any method by which the aeroplane 
could be prevented from rising off the track before 



June, 1004 1 



KXOWI.l'.DCI' \- SCll'XTIl'IC Nl'WS. 



113 




s 

o 



c 
c 

O 
u 
di 



114 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



arriving at the bottom, which it is very apt to do in 
gusty weather. 

By the courtesy of the Mana<:;ement of the Crystal 
Palace, the magnificent grounds of that institution have 
been placed at my disposal, and a most suitable spot was 
soon found beside the Intermediate Lake. Mere I have 
had a larsje staging erected, of which the accompanying 
photographs will give a good idea. 

Mr. C. J. Pilomfield, the well-known architect, very 
kindly undertook to superintend the details of construc- 
tion. This staging is of wood, the upper end beinj,' some 
30 feet abo\-e the level of the lake. '1 he incline is one in 
two, the lower end forming a curve of '10 feet radius. 
The "take off" is on an upward incline of one in ten, 
the lowest portion of the track beint; about ten feet from 
the outer end, which is six feet above the water level. 

The rails are composed of solid slabs of oak securely 
bolted lo the structure, and projected inwards so as to 
allow of runners enijaging on their under sides as well as 
on the upper. They have a gauge of 2 ft. f> in. These 
are carefully smoothed and greased to minimise friction. 
The flying apparatus consists of a boat, flat-bottomed, 
and with a considerably rockered stem, about 20 feet 
long over all, by 2 ft. 6 in. beam. From the sides of this 
project runners of oak to slide on the rails, and also some 
projections which are to engage the under sides of the 
rails in the event of the wind lifting the wings on one 
side, and thus prevent the machine being overturned or 
lifted upwards off the track. 

The rate of descent is found to be 50 feet per second 
near the bottom, but this speed is, of course, diminished 
slightly during the upward incline before the boat leaves 
the track. An electric chronograph is to be fitted so that 
the speed can be measured over various sections of the 
track. The track is only just completed, and the proper 
man-carrying boat is still in hand. 

The photographs show a skeleton pattern boat which 
was constructed to better get at the most suitable 
dimensions and shape. This, as may be seen, was 
fitted with two rectangular aeroplanes, each 12 feet by 
5 ft. 6 ins., so that the area of this model is 132 square 
feet. Later on it is proposed to apply other shapes and 
forms of aeroplane to compare various patterns, and tails 
of different designs will also be tried. 

I propose shortly to start making regular trials and 
shall hope to be able to give full accounts of these in the 
next number of " Knowledge & Scientific News." 

Mr. J. Semenoy (see Journal dc Physique, Feb., 1904) causes 
electric sparks to jump between two gas flames or a flame and 
a metallic electrode, or else between two metallic electrodes 
separated by a small gas flame. By this arrangement the 
glow is eliminated, so as to enable the spark proper to be 
examined separately. In fact the metallic vapours constituting 
the glow are blown aw.ay by the gas stream of the flame. 
The image of the spark is projected by means of a con- 
vergent lense on the vertical slit of a direct-vision spectro- 
scope, the axis of which is perpendicular to the plane of the 
spark gap. 

Semenov's experiments go to show that dirtric currents in 
gases are a molecular phenomenon ; this would be in accord with 
Professor Bouty's researches on the dielectric cohesion of 
gases, which is also a molecular property. 

Such currents are attended l>y the dissociation and projec- 
tion of matter, the paths of which are in each point of the 
spark orientated in a plane perpendicular to the line of current. 
On account of the projection of matter taking place round the 
spark, a vacuum must be produced along the spark, the 
atmospheric pressure throwing into this vacuum the air and 
metallic vapour surrounding the electrode ; this is obviously 
one of the causes of the transport of matter taking place from 
one pole to the other. — A. G. 



The Development of 
Parasitism. 



r.y J. Re'ixolos Grei:n, Sc.H., I'.K.S. 



The early ancestors of all plants now existing are 
generally held to have been aquatic organisms of fairly 
simple type, and of not very complex structure. Without 
going back to the extremely simple protoplasmic entity, 
whose nature cannot be said with certainty to have been 
vegetable rather than animal, we must admit the exis- 
tence of a I'ace of plants, each of which was capable 
of living for and by itself, of carrying on all the functions 
of nutrition, and of reproducing itself. The power of 
nourishing itself involved a further power; it must have 
been able, under the infiuence of the rays of the sun, to 
construct or.Ljanic food material from the inorganic simple 
compounds furnished to it by its enviromnent. The 
possession of this power was one of the earliest acquired 
marks of distinction between the animal and vegetable 
organisms, for though traces of it may be found in the 
former, they are but traces ; and it is uncertain how far 
they actually pertain to the animal world. The vege- 
table organisms on the other hand, bavin"; once acquired 
the power, have retained and developed it till it is now 
recognised as their special and distinctive feature. 

This peculiar property of constructing organic material 
from inorganic, on which all physical life depends, is 
associated with the presence in the vegetable organism 
of a peculiar green colourin,<i matter, known as chloro- 
phyll. The pigment is in nearly all cases found associated 
with peculiar differentiated portions of the living sub- 
stance, known as plastids, which, though commonly small 
ovoid bodies lying in the general protoplasm of the 
organisms, may in the more lowly forms assume curious 
shapes. The power of food construction from inorganic 
materials and the presence of these chUiraplasiids go 
together, and the possession of what is often called 
this chlorophyll apparatus is the distinguishing feature of 
most plants. 

Endowed with this apparatus, exposed to the rays of 
the sun, supplied with such simple inorganic substances 
as the carbon dioxide of the air, the water and the 
nitrates, sulpliates, and phosphates of the soil, the plant 
can fight its own battles and reproduce its race. 

In studying the vast field of vegetation that the face 
of the earth presents us with, however, we come across 
many types which are not nourished in this way, which 
have no power of food-construction, and which can only 
live, animal fashion, on organic materials ready made for 
them. 

Looking more closely into the habits of such plants, 
we can distinguish between two classes of them, one 
thriving on dead, decaying organic matter, the other 
preying upon living organisms. 

The latter form the great group of parasites, a degraded 
class which thrives by robbing other organisms of the 
food they fiave acquired, and by taking from them 
their own vital fluids, causing malnutrition and death. 

The study of parasitism as seen in the \egetable king- 
dom illustrates very fully the law which is so well 
illustrated in the processes of the evolution of the races 
of both animals and plants, that disuse is followed by 
atrophy. Whether the parasitic plant lives at the ex- 
pense of another plant or whether it attacks an animal 
organism, the result is the same — the disappearance of its 



Jl-NE. 1904.] 



KNOWLEDGE c^ vSCIENTIEIC NEWS. 



115 



chlorophyll appai.iUi>. the loss of the power of food- 
construction, and a consequent degradation of structure, 
always found accompanying such impotence. 

The development of the parasitic habit has not taken 
place among one group of plants alone, and the parasitic 
plants are not therefore connected with one another by 
any ties of descent or inheritance. Parasitism has been 
acquired by simple and by complex plants, and ap- 
parently more than one chain of circumstances has k^d up 
to it. 

Among the simpler families wc find the great class of 
bacteria, or germs, in many cases parasitic, liiough others 
live on dead organic matter. Such as the latter are 
designated sapropliytis, and in many cases they mark a 
halfway house to parasitism. A group of somewhat 
higher type is aflorded by the fungi or moulds, which, like 
the former, include both saproph3tic and parasitic 
forms. 

From their structure these parasitic fungi are closely 
allied to the filamentous alga- or sea-weeds, from whicli 
it is clear that they have been deri\ed. There are many 
families of these aquatic organisms, distinguished from 
each other by their peculiar methods of reproduction. 
There are corresponding groups of fungi, and from com- 
parison of them there can be little doubt that the fungi 
have been developed from the alga^ which they resemble. 

The process of their development, though based upon 
existing forms of both, can be fairly satisfactorily traced. 
We have, however, only prohability to point to, for we have 
not very satisfactory transitional forms. The main differ- 
ence between the two is the presence of the chlorophyll 
apparatus in the one and its absence from the other. This 
involves, however, a change of habit of life which has led 
to modification of the structure of the plant body. 

It is not very difficult to see how the parasitic habit 
probably arose in these lowly plants. Their bodies are 
not differentiated into definite members like the higher 
plants, but arelitile microscopic spheres or flat plates, 
or filaments. Many of them now are found to be 
living in a soit of association with each other, not help- 
ing each other further than by supplying mechanical sup- 
port. If we imagine a comparatively large form support- 
ing a number of smaller ones, we can see that its death 
and decay would present to those adhering to it a con- 
siderable amount of organic material ready for consump- 
tion. Such a source of food supply may well ha\e been 
utilised, for its absorption would relieve the adhering 
plants from much labour of construction. A saprophytic 
habit thus assumed would be likely to be permanent, 
and the manufacture of the now unnecessary chlorophyll 
apparatus would gradually die out. 

The forms thus acquiring saprophytism have betn many 
and varied in their form. The great majority have 
been filamentous, consisting of long threads known as 
hyphd . These threads permeate the mass of the decaying 
organic matter. Such are many of our common moulds, 
which are developed now so easily upon syruppy sub- 
stances. 

The passage from this comparatively harmless way of 
getting food to the destructive form of parasitism is not 
very difficult We can trace it in many of the fungi 
which are at our side today. Instead of waiting for the 
death of the plant to which the fungus is attached, the 
latter in many cases kills it by secreting and pouring out 
a toxic substance or poison which causes a local death of 
the tissue with which it comes into contact. Into this 
dead nidus the filaments of the intruder then grow, and 
so its establishment takes place in the interior of its host, 
such growth being preceded by a destruction of the latter, 
the materials so formed being the food of the fungus. 



This conduct marks a stage very near to the establish- 
ment of the true parasitism, which involves only the feed- 
ing of the intruder on the materials of the host plant, 
prior to death and decomposition. This change of nutri- 
tive method soon follows, the intruder gaining the power 
to assimilate the juices of its host without any such de- 
composition. Then the gradual weakening of the host is 
the sign of the in\-adi,'r, which has ceased to manufacture 
the toxin or poison which was at one period a necessary 
phase in the process of the nutrition. 

We cannot point to organisms which are at present in 
the early stages of this transformation of nutritive pro- 
cesses, but certain fungi can be found which have hardly 
passed beyond that of the loss of the chlorophyll appa- 
ratus. One which is known as Pythiitm attacks young 
lettuce seedlings, causing the disease known as dniiipinf^ 
of. This illustrates the change ; it has no green colour, 
and gains all its food from the lix'ing tissue of the seed- 
lings, but its structure, and especially its modes of repro- 
duction, are strikingly lik'e those of the alga? to which it 
is related. The reproducti\e cells which it forms, their 
shape, and structure, the mode of their formation, andlheir 
general behaviour are strikingly algal. Among the 
various species of the genus we find forms whicli are 
gradually losing these algal peculiarities, andare beginning 
to show the degradation of structure which always is 
associated sooner or later withthe parasitic mode of life. 

Besides these pathogenic forms, bacterial and fungal, 
associated emphatically with a diseased condition of the 
host plant. Nature shows us others which are much 
higher in the scale of organisation, belonging iiuleed to 
the highly organised flowering plants. When we pass 
in review a series of these parasites we find the same 
succession of events, the acquirement of parasitism ac- 
companied by a loss of the power of constructing organic 
substance and a progressive degradation of the whole 
organism. 

In tracing the development of the habit among these 
higher plants we find suggestions that it originated in a 
different way from that which we have noticed among 
the fungi. Saprophytism is not unknown among the 
flowering plants, but it has apparently had no part in the 
development of parasitism. The origin of the latter 
must be looked for in the close relationship often found 
existingamong plants which were originally nothing more 
than neighbours, by virtue of which they came to help one 
another in a peculiar manner in the struggle for existence. 
This relationship, known as symbiosis, is a union of two 
plants for their mutual benefit. It is seen in many cases, 
conspicuous among which we have the lichens, peculiar 
organisms consisting of an alga and a fungus living in 
close relationship with each other, each contributing a 
share to the well-being of the compound organism. 

The origin of such symbiosis among the higher plants 
can be seen in the case of a group of plants often known as 
roolparasilcs. They include many members of the Natural 
(_)i(ler ScrophuliU'iiKr, e.g., the yellow-rattle which grow 
in pastures and waste ground. The roots of these plants 
are growing freely among the roots of the other plants, 
the grasses, &c., of the pasture. Coming into contact 
with these, the irritation of the contact causes a swelling 
to arise upon the root of the rattle, and from this growth 
delicate filaments emerge which penetrate the grass root 
and set up an intimate relationship between the two, 
which become so far united that liquid matter can pass 
with comparative ease from the one to the other. The 
relationship so set up is not particularly harmful to the 
grass ; indeed, it seems to be beneficial to both symbionts, 
bringing about in a way an eijualisation of the nutritive 
material that both are engaged in making. It involves 



ii6 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



no diminution oi i.ic < ulorophyll of either, and no degra- 
dation of structure. 

.\ further stage in the acquiremeni of tlie parasitic 
rather than the symbiotic habit is exhibited by the mistle- 
toe and its allies. We are most of us familiar with the 
mistletoe, an evergreen plant with pale greyish-green 
lea\es, found growing on the poplar, apple, uVc. It arises 
in all cases from the germination of seeds deposited by 
buds in the bark of the branches of the host. The young 
rootlet of the mistletoe inserts itself into the bark, and 
penetrates the soft tissues of the cortex as far as the j-oung 
wood. Subsequent growth and development, which are 
accompanied by the co-incident grow-th and increased 
thickness of the branch, lead to the establishment of a very 
close union between the tissues of the two, and as the 
plumule of the seed develops and the upper portion of the 
mistletoe plant increases, the two are so firmly joined that 
the organic food of the host is easily absorbed by the 
intruder. The relationship is still symbiotic, for while 
during the greater part of the year the host plant feeds 
the mistletoe in preponderating measure, in the winter, 
after the leaf-fall of the host, the evergreen guest contri- 
butes to the nutrition of both. The plant shows, however, 
the beginning of the inequality of symbiotic eflfort which 
is the antecedent of parasitism. Co-incident with this w'e 
find the beginning of the degradation of the chlorophyll 
apparatus, the mistletoe possessing leaves of very grey- 
green colour. 

The inequality thus established can be traced a stage 
further in the genus Orohaiichc, the so-called broom -rapes, 
which are far from uncommon among our wild plants. 
They consist of a large fleshy stem ending in a spike of 
flowers ; the stem bears a few almost rudimentary 
leaves which are almost brown, having but little green 
matter in them. The broom-rape is found seated upon 
the roots of some other herbaceous plant, and is furnished 
with a greatly thickened and swollen base by which the 
attachment is made. The swelling is cfue to the absorp- 
tion of nutritive matter from the host plant, which is now 
almost the only source of food possessed by the intruder. 
Parasitism is practically established; the chlorophyll 
apparatus of the broom-rape is rudimentary and abortive, 
and the burden of feeding both falls upon the host plant 
which suffers in consequence. 

The common Dodder shows as yet another stage. The 
plant infests many herbaceous plants, especially clover. 
The seed germinates on the ground, and the young embryo 
twines itself around some neighbouring stem. Having 
established its hold, it forsakes the ground, and in all its 
subsequent growth it twines more and more fully round 
its host. The long twining stem bears no leaves, and 
contains no chlorophyll. At intervals along its course it 
puts out sucking root-like filaments, which perforate the 
host and set up a close union between the tissues of the 
two. So fed, the Dodder flowers and seeds, altogether at 
the expense of its host. 

Our own flora shows us no more complete instance of 
a parasite than this. In some tropical areas a parasite 
can be met with which lives entirely wrapped up inside 
the tissues of its host. The degradation of its structure 
is complete, for its anatomical complexity is reduced to a 
very close resemblance to the hyphal network of a fungus. 
I lere and there an outgrowth of the plant penetrates the 
surface of the host plant, and develops into a flower, 
which in some cases has an enormous fleshy body. The 
parasitic habit now dominates the plant ; it lives only to 
produce its flower, it has lost all trace of normal struc- 
ture, it obtains everything from the internal tissues of its 
host, and stands before us indolent, atrophied, and yet 
triumphant. 



The AvitobiograpKy of 
Herbert Spencer. 

The late Mr. Herbert Spencer has written his " Auto- 
biographj- " (Williams and Norgate) in a vein of exceeding 
seriousness. Other men who have written their autobiogra- 
phies endear themselves to their readers by their unconscious 
revelation of character, even their human weaknesses. Mr. 
Herbert Spencer had no human weaknesses ; he appears in his 
autobiography as the personification of abstract thought. It 
is true that he was a dutiful son; indeed, in speaking of his 
mother, he approaches more nearly to tenderness than on any 
other occasion, but even here he displays that detached clear- 
sightedness that characterises all his relations in life. •• Of 
my mother's intellect there is nothing special to be remarked," 
he comments, and adds with that one touch of feeling already 
mentioned. " speaking broadly, the world may be divided into 
those who deserve little and get much, and those who desene 
much and get little. My mother belonged to the latter class : 
and it is a source of unceasing regret with me that I did not 
do more to prevent her inclusion in this class." The reader is 
feign to share her son"s retrospective sympathy for Mrs. 
Spencer when he learns something of her husband's irritating 
characteristics. " He held, for instance, that everyone should 
speak clearly, and that those who did not ought to suffer the re- 
sulting evil. Hence, if he did not understand some question 
mv mother put, he would remain silent ; not asking what the 
([uestion was, and letting it go unanswered. He continued 
this habit all through life, notwithstanding its futility. " Mr. 
Spencer arraigns his earlier Huguenot and Wesleyan pro- 
genitor? in the same scientific spirit, tracing in his own 
character kindred traits derived from them. " That the spirit 
of Nonconformity is shown by me in various directions, no one 
can deny, " he says in conclusion. ■' The disregard of authority, 
political, religious, or social, is very conspicuous. Along with 
this there goes, in a transfigured form, a placing of principles 
having superhuman origins above rules having human origins, 
for throughout all writings of mine relating to the affairs of men. 
it is contended that ethical injunctions stand above legal in- 
junctions." 

The elder Mr. Spencer postponed his son's education on 
grounds of health ; but, desulton,- as it was, at thirteen he bad 
acquired considerably more general knowledge than is com- 
mon at that age. Of Latin and Greek, he knew '• nothing 
worth mentioning." Of English grammar or history, he was 
entirely ignorant, and the deficiency in bis literary education 
makes itself felt in the roughness of his English; but, on the 
other hand, " my conceptions of physical principles and pro- 
perties had considerable clearness, and I had a fair acquaint- 
ance with sundry special phenomena in physics and chemistry," 
.\ far more important mental acquisition, and one in which 
school education is conspicuously deficient, was what Mr, 
Spencer describes as the habit "of intellectual self-help," 
which his father was continually inculcating. Shortly after he 
was thirteen Herbert Spencer went to continue his education 
at the house of an uncle, where be seems to have derived more 
benefit from mental and moral discipline than the actual ac- 
quisition of knowledge. Soon after his return home he entered 
on a brief career as a teacher, his father's profession. In 1S57 
he obtained a post under Mr. Charles Fox, Permanent Re- 
sident Engineer of the London division of the London and 
P)irmingham Railway during its process of construction. 

" I arrived in" London on the Sth November, 1S37. . . . 
The Queen, who had but lately succeeded to the throne, and was 
not yet crowned, dined with the Lord Mayor in the City on the 
qth of November, and the occasion called for a State Pageant. 
It was the only Royal procession or display of allied kind 
which I ever saw. " He adds later: '• I was quite alive to the 
responsibihties of my post and resolute to succeed. During 



JlNE, 1904.] 



KNOWLEDGH \- SCII-NTIFIC NEWS. 



117 



the whole of my sojourn hi London, lasting over six nioiiths, 1 
nevor went to a place of anuisement ; nor ever road a no\ el or 
other work of light literature." It was surely this ituapacity 
for healthy recreation, ingrained l>y his education, that was 
largely respousilile for the ill-health .tnd nervous strain w ,th 
which Herbert Spencer had to coiiteud during his later years. 
t)ne cannot read without a smile his grave aniul.ldv^■r^iolls on 
the eoenpanions with whom he was thrown at tlie ( iigiiuering 
oflicesat Worcester, to which he subsequeutly went. " I'nlike 
the pupils of Mr. Charles Fo.\, quiet youths, carefully In ought up 
(two of them being sons of dissenting iniiiisteisl. the junior 
members of the Birmingham and Gloucester stalV belonged 
largely to the ruling classes, and had corresponding notions 
and habits." . . . "The superintendence was not rigid. 
and the making of designs was intei perseil now with stoi lis not 
of an improving kind, now with glances down on the pas.sers 
by, especially the females, and resulting remarks; there being 
also a continuous acconipaninient of whistling and singing, 
chiefly of sentimental ballads." .\mong these young men 
Herbert Spencer was, however, able to form one coiigtnial 
intimacy, which we remark upon becau.se it instances .igain 
that detached ijuality ofmindaUeady mentioned, tli.it liabil ot 
appraising his fellows, even his most intimate fiiends. " lie 
was the son of Dr. Jackson, at that time foreign Secret. iry to 
the Bible Society. Of somewhat in)gainly build, and with an 
intellect mechanically receptive, but without much thinking 
power, my friend was extremely conscientious. ' . . . ".As 
sociation with a man whose intellectual powers weie above niv 
own would have been more advantageous," he adds. 

.About this period. Herbert Spencer notes that religious 
belefs were slowly losing their hold, "the creed of Christen- 
dom being evidently alien to my nature, both emotional .iiid 
iutellectiial." "Criticism," he coiitinnts, " liad not yet shown 
me how astonishing is tlie supposition that the Cause liiim 
which have arisen thirty millions of .Suns, with their attendant 
planets, took the form of a man, and made a bargain with 
.Abraham to give him territory in return for Allegiance." " I 
had not at that time." he continues, " repudiated the notion 
of a deity who is pleased with the singing of his praises, and 
angry with the infinitesimal beings he has in.ide when they 
fail to tell him perpetually of his greatness." an extraordinary 
crudeness of statement " of the Creed of Christendom," wliich 
can only be accounted for by Herbert Spencer's Noiu on- 
formist antecedents. 

In 1S41, Herbert Spencer returned home, partly to i)insue 
a course of mathematical study, and jjirtly to carry out his 
father's idea of an electro-magnetic engine. Neither scheme 
was pursued. It is curious to find him continually comment- 
ing on his "constitutional idleness," which "has t.iken the 
form of inability to persevere in labour which has not .in 
object at once large and distinct." The years that followed, 
though they were apparently desultory and futile iroin the 
point of view of material advancement, were of crucial im- 
portance in the history of Spencer's subsequent career, .uid 
in determining the bent of his genius. He instances, as a stc p 
in his mental development, the letters on social ipieslions 
contributed by him to the Xoiicuiijoniiist, an organ of th(- 
Advanced Dissenters, letters which originated in political 
discussions with an uncle, who introduced liini to the editor : — 
" Had they never been written. Social Statics, which 
originated from them, would not even have been thought 
of. Had there been no Social Statics, those lints of 
enquiry which led to 'The Principles of Psychology' 
would have remained unexplored. .And without that 
study of life in general, initiated by the wiiting of these 
works, leading presently to the study ot the relations 
between its phenomena and those of the inorganic 
world, there would have been no System of Synthetic 
Philosophy.'' 
Meanwhile, he was besides variously occupi d journalisti- 
cally and otherwise, and in 1S50 appear(;d his first book, 
" Social Statics ; orlhe Conditions Essential to lliiman Happi- 
ness Specified." "Assuming happiness as the end to l)e 
achieved, it regarded achievement of it as dependent on 
fulfilment of conditions, conformity to which constitutes 
morality." 

After the appearance in 1S55 of his second book " The Prin- 
ciples of Psychology," he suffered from a serious breakdown 
in health which enforced a long period of idleness. To these 
two books Mr. Spencer appends with characteristic aloofness 



of mind two hypothetical reviews, criticising his own .ugu 
mcnts .iiul suinmaiising his doctrims. .-Xs soon as his he;illh 
w.is sullicii'iitly recovered, he set to woik upon his " .System ol 
Synthetic Philosophy." He describes himself at this time as 
"a nervous inv.did " " h.iving only iirecarious resources," and 
his undertaking, so inonuinental .a task, necessitated ;i heroic 
struggle with physical weakness. Aftii the public. ition of the 
first e.irly part of the work he found hiinseU obliged to decide 
upon the abaiulonmtnl of his design. His parents wer(^ in 
need of his support, and he had already trenched considerably 
upon his small capital. The proposal iinniediatelv called 
forth the following generous response fioin J. S. Mill: 

" It is right that you should be indeinnilied by the readers 
and puicha.sers of the series for the loss you have inciured l>y 
it. 1 should be glad to contribute my part, and should like to 
know at how niucli yon estimate the loss, and wlu-tlu-r you 
will allow me to speak of it to Iriends.uid obl.iin ^>ubscriptions 
lor the remainder." 

The propos.il was (■ventually declined. The de.ith of the 
elder Spencer lessi^ned his son's responsibilities, and .American 
.admirers placed 7000 dollars to his credit in public securities. 
01 Herbert Spencer's rel.itions with his contemporaries we 
have hardly space to jpeak. One instance must hulTue ol the 
shrewd but inercilets clear-sightediu ss with which lie esli 
mated the mental .and moral calibre of his ac(|uaintances. ( )f 
Cailyle lit- .says: " He has, strange to say, been elas.sed as a 
philosopher! Considering that he either could not or would 
not think coherently — never set out from premises ;inil 
reasoned his way to conclusions, but hal>itually ihalt in intui- 
tions and dogmatic as.sertions, he lacked the trait which, perhaps 
more than anv other, distinguishes the philosopher properly so 
called. He Licked :ilso a further trait. Instead of thinking 
calmly, as the philosopher above all others does, he thought 
in ;i |)assion. It would take much seeking to'find one whose 
intellect was perturbed by emotion in the same degree." 



Photography, 

Pvire a-rvd Applied. 



]jy ClIAIMAN JnxKS, I'.I.C, I'.C.S. 



In introduciii.L,' the first of the Photographic sections to 
the readers of " Know 1 1 ik.i ," it is lit that I shoulil s:iy 
soniethin;^ as to llu- geiitial character of the matter that 
they may i xpcct to liiul in this part of the jomiial. 
li\ci)oiie may now lie considered to lake a practical 
interest in photography, just as everyone knows how to 
write his own language intelligibly. Therefore it will be 
my endea\oiir to deal with matters connected with the 
practice of tlu- ait :is ojjpoi tunity seems suitable. A few 
perhaps lake an iiiteresl in photography for its own sake; 
and as the pure science of to day may be regarded as the 
ap|)lied science of tomorrow, I shall hope to draw the 
attention of readers to notable items of progress in photo- 
graphy, even though their immediate application may 
not be very obvious. Hut in all cases it will be my 
endeavour as far as possible to meet the needs of all who 
take the trouble to read these notes, and to enable me to 
do this 1 shall welcome any suggestions or questions of 
general interest, anil the account of any photographic 
experiences, whether in connection with scienlilic work 
or the general practice of the art. 

'I'lic Rcmicriii'^ of Colony. — It is a notable sign of the 
times that the only films now made by the Kodak Com- 
pany are colour sensitised or isochromatic. .Although 



ii8 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



colour-sensitised plates have been available for many 
years, and in photo-micrography and other scientific work 
they have long been considered as indispensable, even 
those who know the advantages that they offer too often 
appear to lose their critical sense as soon as they take 
their cameras out of doors. It is a mistake to suppose 
that the proper rendering of variously-coloured objects is 
an artistic matter; it belongs to the realm of science, and 
the reason that it is neglected is that we have got so used 
to the conventional errors in the representation of coloured 
objects in monochrome by photography that they do not 
offend the eye as errors in outline do. Another reason 
is, I think, that it has so often been represented of some 
colour-sensitised plates that they do not need a coloured 
screen, that many who have seen the results of their use 
without that assistance have been unable to find any 
advantage in them. There is no available colour-sensi- 
tised plate that will give an advantage worth having 
in ordinary work by daylight, even if detectable by 
critical examination, unless it is used in conjunction with a 
coloured screen. The sensitiveness to blue light is so 
overpoweringly great that the little added sensitiveness 
to green, yellow, or red is lost unless the blue light is 
reduced. And the deeper the colour of the screen the 
more correct will the resulting photograph be so far as 
the use of well-known commercial screens (or light filters 
as some call them) is concerned. By the injudicious use 
of dyes it is easily possible to absorb so much blue that 
this colour photographs as if it were black, while yellow 
and green will appear as if white. It is safest not to use 
a screen that requires the exposure increasing to more 
than about eight times, unless one has some guarantee 
that it is suitable. At about this stage, and beyond it, it 
becomes necessary to adjust the screen to the particular 
plate that is to be used. It is a mistake to suppose that 
a coloured screen renders exposures outrageously long. 
The screen that probably requires a greater increase of 
exposure than any other on the market, the "Absolutus " 
screen made by Messrs. Sanger Shepherd, and Co. to 
suit Cadett's spectrum plates, and it requires exposures 
out of doors to be increased about forty times, as a rule 
only needs the giving of a few seconds' exposure instead 
of a fraction of a second. For hand-camera work, it is 
well to have a screen that needs the exposure to be 
doubled, and also one that requires it to be increased to 
four times or more for use when circumstances permit. 
It is well worth the little extra trouble involved if only 
tor the sake of the improvement that will be manifest in 
the skies, especially when these are partly or wholly 
cloudless. 

Catatypc. — This interesting process seems to be still in 
the dcnibtful stage so far as its practical uses are concerned. 
It was patented nearly three years ago by Messrs. Ostwald 
and Cirus, and is one of the results of Professor Ostwald's 
investigations in connection with catalysis. Finely 
divided metallic platinum or siKer causes the decomposi- 
tion of hydrogen peroxide when merely brought into con- 
tact with it. If, therefore, a photograph in which the 
image consists of metallic silver or platinum is flooded 
with a solution of peroxide of hydrogen in ether, when 
the ether has evaporated the peroxide will be decomposed 
where it is in contact with the finely divided metal, and 
if the original is a negative there will be on it an invisible 
positive image in hydrogen peroxide. By pressing such 
a treated photograph against a gelatine film for about 
thirty seconds, a notable quantity of the peroxide will be 
absorbed by the gelatine, and such a " print " can be de- 
veloped, or made to give a visible result in many ways. 
An alkaline siher solution will give a black image of 
metallic silver, an alkaline lead solution a brown image 



of lead peroxide, and so on. By treating such a print 
with a f( rrous salt, the peroxide will convert the ferrous 
salt inti a ferric salt and this will render the gelatine 
insoluble in water. If the gelatine has been mixed with 
a pigment, as in ordinary carbon tissue, and the print is 
developed by means of warm water as an ordinary carbon 
print is developed, it is stated that this method of pro- 
ducing carbon prints gives the print ready for develop- 
ment in about two minutes instead of the time usually 
required to sensitise the tissue with bichromate, dry it, 
and expose it behind the negative. The process may 
also be available for photo-mechanical work, for it is 
stated that gelatine that has absorbed peroxide of hydrogen 
will take up a fatty ink after the manner of chromated 
gelatine that has been exposed to light. It is to be hoped 
that we shall soon hear more of the practical applications 
of these methods. 

(To he continued.) 

The Antiquity of the 
Constellations. 



Tl) THE EdITOUS of " KNOWLEDGE." 

Gentlemen, — Let us hope that Mr. Maunder may tell us 
more about the origin of the constellations. The late Mr. 
Proctor was very bold and fixed the date at which they were 
invented (or revealed) at 2170 B.C., neither more nor less. Mr. 
Robert Brown, too, one would gather, was given (liUe Balbus) 
to rashness in speculation. 

Mr. Maunder puts the approximate date at 2800 b.c. But 
some difficulties suggest themselves on the brief summary of 
his arguments, f./,'. : — 

(i) The centre of the space not included in the ancient 
constellations must have been the S. pole of the period 
when they were designed. 

But do we Unow all the ancient constellations ? A recent 
w-orli, " Sphacra " (referred to below), gives, not 48, but some 
150. Many are duplicates (and the variants are curious and 
interesting). Others are quite unidentified, i'.,^'., the market 
place, the two skulls, tlie stag with two snakes in his nostrils. 

(2) The tradition of the four royal stars marking the 

colures. 
But Rcgulus was a " royal " star for an obvious astrological 
reason. It was the heart of the royal beast, the lion, and was 
supposed to rule the fates of kings. (The star called Cor 
Hydrae, or the serpent's heart, denotes trouble through 
women.) If t!ie Persians called other stars "royal" they 
may have liad ecpially good (or bad) reasons of the kind. 

(3) The date gives the only symmetrical position for the 

actual constellations of the Zodiac. 
But then- is a strong tradition that they were originally 
eleven, nut twelve, and their position otherwise is far In mi 
symmetrical. 

(4 1 The ascending signs at this date laced east ; the 
descending west. 
But why did three face nowhere iu particular ? Manilius 
gives amusing explanations. 

(5) There arc traditions of Taurus leading the Zodiac. 
Possibly, l)ut the familiar lines of Vergil in the first Georgic 
do not prove this. 

It is not safe to base arguments on poetry, and, iu fact, 
Seneca finds fault with the agriculture of this very passage 
(Ep. 86): "()nr Virgil considered effect more than truth and 
wished to please his readers, not to teach farming." But the 
astronomy is right enough. Virgil is thinking of .'\pril, and 
Ovid's lines (Fast IV. 88) arc the best explanation ; — 
Nam. quia ver aferil tunc omnia, densaijue cedit 

Frigoris asperitas, fetaque terra patet ; 
Aprilem memorant ab aperto tempore dictum. 

or 

When that Aprillt with his showrts soote 
Tlie drought of March had perced to the roote. 



Jlne, 1904.] 



KNOWLEDGE lS: SCIENTIFIC NEWS. 



119 



AccordiDg to ColunK'll.i the sun enters Taurus on April 17, 
and the dog sets with the sun on the last day of the numth. 

My principal object in writins; this letter is to call attention 
to the German book {" Sphaera," by Fran/ Boll, Leipzig ; 
Teubner. 1903) above referred to, which gives new Greek 
texts, and sheds a flood of li.ght on the history of the constella- 
tion signs. 

The new texts arc astrological, and indicate a promising 
field of investigation. 

One vexed problem which is incidentally solved is that of 
the so-called Zodiacs of Dendera, which, though neither 
Zodiacs nor pictures of the heavens at any date, arc shown to 
be of capital importance in a new direction. 
I am. Gentlemen. 

Your obedient Serv.ant, 

T. K. AnNOLD. 

23. West Side, Wimbledon, 
Feb. iS, 1904. 



[Mr. Arnold has not quite understood the significance of Dr. 
Franz Boll's valuable work. The new Greek texts discovered 
and discussed by him have no direct bearing on the origin and 
antiquity of the constellations. They were found in late 
mediaeval manuscripts and consisted of excerpts from astro- 
logical writers of the first to (he fifth centuries of our era. 
The chief interest attaches to the discovery of some texts of 
the writings of the Babylonian astrologer Teucros ; perhaps 
better known to P'nglish readers as Zeuchrus, who lived about 
the Christian era or in the first century a.d. Mr. .Vrnold has 
apparently been misled by Dr. Boll's use of the word " sterii- 
bildcr." The additional constellations of which Mr. Arnold 
speaks are mostlv not " constellations " at all in the sense in 
which we ordinarily use that word, i.e., groups of actual stars, 
but are simply decanal symbols. The •• decans," or portions of 
the ecliptic ten decrees in length — th^(^e therefore to each sign 
of the Zodiac — go back to a great antiquity, but are necess.Trily 
of much later date than the original ma])|>iug out of the constel- 
lations. For the actual constellations are most irregular in 
length, and the division into decans implies that the ecliptic had 
been previously divided into twelve equal parts, bearing 
only a rough relationship to the constellations and not 
corresponding to the actual stars, though the new " Signs " 
naturally took their names from the old " Constellations." 
The symbols attached to the 36 decans are therefore not 
truly stellar at all ; they partly look back to the Egyptian 
system of placing the year under the protection of 36 deities, 
partly to the association of each of the twelve zodiacal 
constellations with its " paranatellont;i " or extra-zodiacal 
constellations, and p.artly to the desire of the astrologers to 
have a fuller supply of prognostics to work with than the 
twelve signs .ilone could give. Thus the " Agorii," or Market 
Place, mentioned by Mr. .\rnold, was in tlu' second decau of 
Libra; and was clearly lint an enlargement of the idea sug 
gested by the Balances, of buying, selling, and weighing. 
It is not a question of an actual star group bearing 
that name. It simply indicated the middle ten degrees of 
longitude of the •' Sign " Libra. The •' two skulls " are neither 
new nor unidentified. Dr. Boll himself points out that they 
are mentioned Ijy Albnmasar, one of the best known of 
mediieval astrologers of the Ninth Cintmy a.o. They are 
placed, usually with other symbols, in tin- third dee.in of 
Libra, and quite possibly are nothing but a very coniipt form 
of the " He.ivenly Twins," Adonis and Aphrodite, Tannrmz 
and Istar, /.I-., the Sun and Moon. 'I'here is no reason for sur- 
prise that so much variation is found in the symbols attached 
to the decans and their sub-divisions. They never had the 
authority, for they had not the antiquity, of the consti'Ilations, 
and many, no doubt, owed their origin to the caprice of indi- 
vidual astrologers, or to an imperfect understanding of symbols 
employed in foreign systems. Dr. Boll's work supplies some 
interesting cases of the wide differences shown in m.iimscripts 
professedly based upon the same original authority. 

.^s to another point raised by Mr. Arnold, the conslellaticins 
of the Zodiac, so far as we can trace them with cert.unty, 
were always accounted twelve, even if only eleven separate 
figures were shown. The Scorpion had a double portion 
allotted to him in schemes which did not display the B.ilance ; 
sometimes, as in tlx^fireek sclu-me, his claws extended to the 
feet of Virgo; sometimes a second scorpion took the place nosv 
held by the_Balance. But it will be noted that Libra is recog- 



nised by the astrological scheme ; so lliat whenever tin: B.il- 
ance was introduced it nnisl liave been before the working out 
of systematic astrology, and befoietlu- division of the "signs" 
into '■ decans." 

Mr. Arnold's explanation of the name of Kegulus does not 
lead us far. It leaves unexplained why a lion was designed in 
that part of the sky. But if Kegulus got its name of •' King " 
wlien it marked actually the higlic-st point of the ecliptic, on 
account of its pre-eminent position, it would not be very 
mmatural that the form of the ■• King of Beasts" should be 
figured out round it. The Southern l''ish and the Scorpion 
.are certainly not ''royal" beasts at .ill: the Hull ([ueslion.ibly 
one ; so that no astrological reason is likely to have gained 
that title for l^omalhaut, Antares, and .'\ldebaran. But their 
relation to the other cohues being so simil.ir to that which 
Kegulus held to the colure of the sunmier solstice may well 
have caused thetitle to be extended to them ; especially astlie 
date indicated agrees so will with (h.it suggested by the un- 
mapped space in the south. 

I'he three signs which face nowhere in particul;u' are Libra, 
which had no face to turn, and Pi-sces and (iemini, which had 
each two, looking in opposite dii'cctions. DoiibtU'ss the 
ancients had some special reasons for making the h'ishes swim 
away from each other, and the Twins face each other, but I 
fear it would be only guess-work to suggest them now. It is 
clear that tlie nine remaining signs, which have all one face 
apiece, are arranged as I state. 

Is not Mr. Arnold a little inconsistent in saying that " it is 
not safe to base arguments on poetry" and tlu;n immediately 
proceeding to adopt the methotl he condemns ? And how 
does lie know that V'ergil was thinking of .-Xpril ? The n^al 
significance of the familiar quotation from the Geurgics lies in 
the fact that not only did the Kam actually "open the year" 
in Virgil's time, but that it was generally recognised as doing 
so. The i|uotations from (.)vi(l and Columella are as little re- 
levant to the ([uestion before us as the one from Chauct;r. 

Dr. Boll's examination of the planisphere of Denderah is 
sutficient to show, what has long been recognised, that th.at 
monument can throw no light upon the anlicinity of the con- 
stellations. — E. Wai.tku Maunuku.J 

The MecKaLrvicoLl StaLte 
of the S\jn. 



i!y I'rofeshor K. A. S.\mi'son, I'Mv.S. 



A Gi.ANCic backwards at tlie theories wliitli have altenipted 
to give a reasoned and connected view of current knuvv- 
le(l,t;e of the Sun sugf,'ests that kn()wled,t,'e and theory are 
coriiplenientary, .so much more detailed and precise was 
tlieory when little or nothinj.; was known. It was from 
little more than the tlarkiiess of the sunspots, with 
Wilson's theory that they were de[)ressions in the photo- 
sphere, that Sir William I lerschel elaborated his doctrine 
of a Sun with iuhabiiaiits and luxuriant vej,'etation ; ■ and 
if it is now clear tlnit we shall need an imaj^ination as 
intrepid as 1 lerschel s to realise the state of the Sun, it is 
no less clear that it must be a vastly more creative 
imatjination. 'J'hankstophotof,'raphy,of which M. Janssen 
has for so long given us such admirable examples, thanks 
above all to the spectroscope, which, in its latest ap[)lica- 
tions in the spectrolieliograph, actually maps out the 
forms of clouds of hydrogen and calcium at different 
levels of the Sun's atmosphere, we seem to have the 
means of gaining some real knowledge of the structure 
as well as the composition of the Sun's atmosphere. 
N(jr are these the only signals that tlu;ory should hold 
its peace. A fresh discussion of the sl.atistics of sunspots 
and prominences by Sir Norman Lockye^r has shown 

* The doctrine is not yet extinct ; t have mel jiersuns, hardly in 
middle life, who learnt it at school, and held it without question. 



120 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



that the familiar eleven-year period is resolvable into the 
separate progresses of three or four simpler elements, 
which overlap one another and severally arise and dis- 
appear within seven or eight years; and a consideration 
of the Stonyhurst magnetic records by Father Cortie has 
served to prove how indefinable in the present state of 
our knowledge is the bond coimecting magnttic storm 
with solar outbursts. In the presence of rapid and 
promising developments on the one hand, and increasing 
doubt upon the other, reserve in formulating any theory is 
unavoidable. No great confidence can be placed in 
arguments not based upon consideratijns which are of 
the widest generality, and cannot under any circum- 
stances lie falsified; such, for example, as the laws 
by which such a body must graduilly condense under the 
infiuence of gravitation and loss of heat. Even here it is 
necessary to make somewhat sweeping assumptions before 
any precise conclusions can be drawn, and there is con- 
siderable disagreement among the results at which 
ditferent authors have arri\ed. Vet 1 believe some plain 
and necessary outline can be drawn which will co\er 
many of the most prominent facts. Though such an in- 
vestigation relates more directly to the conditions prevail- 
ing within the body of the Sun than to the state at the sur- 
face, with which it might at first appear that we were alone 
concerned, its bearing upon the latter question is intimate. 
Thus Professor Schuster has said that the main differ- 
ence between stars which show a spectrum like our Sun, 
filled with metallic absorption lines, and those which, like 
Vega, show only the absorption of hydrogen, is neither 
m(jre nor less than the UKjre thorough mixing up of the 
atmospheres of the former ; " if we could introduce a 
stirrer into a Lyrac there can be no doubt whatever 
that the low-temperature lines of iron would make their 
appearance." If this be true, the stirrer we are seeking 
consists of more or less violent convection currents, and 
in order to form a just estimate of how efficient these 
may be we should study that instability which in great 
or small degree is always present where convection 
currents exist. 

Instability with bodily interchange of mateiial does 
\isibly exist in the Sun, and must do so, or else its face 
would soon be covered with a dense luask of relatively 
cold matter; it is radiation which sets this instability up, 
and the key to understanding it is some comprehension 
of the process of radiation. For example, it should be 
realized very clearly that a comparison of the radiant 
energy emitted by two bodies is no comparison of their 
temperatures unless they are in similar stales ; thus a 
solid body maintained at a certain temperature radiates 
sensibly as from its surface; but if it be finely divided, 
and its parts scattered, it will radiate enormously faster 
from the same temperature, since its surface will be 
enormously nuiltiplied. Mence, if a sunspot appears 
nearly black in comparison with the rest of the disc, or 
if, as in M. Janssen's photographs, we see the whole 
surface mottled over with minute brilliant spots upon a 
darker background, the simplest explanation is that the 
brighter parts represent matter diffused in cloud, and the 
darker parts are relatively dense and conglomerate. 

In my opinion, the whole internal state is dominated 
by radiation, for apart from this source of loss of heat, 
there is no reason why the body should not settle down 
to any law of distribution of its matter in which the 
density did not increase from the centre outwards. But 
I must profess myself a total disbeliever in the state 
of affairs whicli it is commonly asserted would in con- 
se<]uence arise. 

This state is Lord Kelvin's well-known " (^onvective 
Equilibiinm " of temperature. I )iscuisiiig in 1862 the 



state of the earth's atmosphere, and observing how winds 
and other currents mingled together with great rapidity 
portions of air which had been widely separated. Lord 
Kelvin adopted the hypothesis that the temperature at 
different levels must be such that this indifferent mingling 
should not change it ; in other words, the excess of heat- 
energy possessed by a portion of air at a lower level of 
the atmosphere, and at consequently greater pressure and 
density, must be just sufficient to expand the same por- 
tion to a pressure and density in equilibrium with those 
at any level above to which it may be transported. The 
same law he afterwards adopted as regulating the whole 
internal state of the Sun, and many other eminent 
authorities have followed him, the latest and not the 
least of whom is Professor Schuster. If it is true of the 
Sun, we must allow that the Sun's density diminishes 
somewhat rapidly from the centre outwards, while the 
temperature from the surface to the centre rises with a 
great rapidity, which is maintained without much decline 
right throughout the whole body and reaches millions of 
degrees centigrade before one-tenth of the radius has 
been measured. 

No doubt we must be prepared for some extravagances 
in theorising upon matters so little known, but it is 
at any rate safe to keep as far as possible from tempera- 
tures measured in millions of degrees ; and in spite of 
the long acceptance of the theory of convective equili- 
brium in the Sun and the formidable array of authority 
by which it has been adopted, I confess I can find no 
reason why it should be supposed to exist. On the 
contrary it appears to me that if we can imagine it to be 
artificially set up, it would require forces to maintain it 
for which the circumstances make no pro\'ision. For if 
a body of gas were arranged according to this law, behind 
some screen which prevented it from losing energy by 
radiation, and the screen were then removed, wliat would 
happen ? All portions would commence to lose heat, the 
outer portions very rapidly by mere radiation; but the 
inner portions also, in part by radiation, because they 
were less screened outwards than inwards, but chielly 
because the outer chilled portions which had already 
lost the heat that allowed them to maintain themselves 
at the higher level descended upon them and shared in 
their stores. This would go on without any attempt 
on the part of the body of gas to restore the state of con- 
vective equilibrium, because no instability would occur 
which would give rise to convective currents mingling to- 
gether the matter from separated regions, until the body 
had departed materially from the rapidly- varying density of 
convective e(iuilibrium and had passed that of a density 
uniform throughout the mass. Even then the currents 
would only be proportionate to the degree by which a 
uniform density was overstepped, and except at the outer 
surface, where it is impossible to escape from a high 
degree of instability and conser]uently violent convective 
currents, the density would apparently be left in a state 
which might perhaps fluctuate a little, but would be but 
very little removed from a state of uniformity. It would 
follow that the temperature was also substantially the 
same throughout the bulk. Or again, if we reverse our 
attitude and suppose a body set up with density and 
temperature nearly uniform throughout its body, but on 
the whole very slightly increasing outwards and therefore 
liable to slight convective currents— excepting at the 
surface — and ask what forces would be found which could 
materially disturb such a state, none can be mentioned. 
Kadiation which appeared as an acting cause lending to 
set up such a state will be inoperative when that state is 
attained — excepting again the surface — and conduction 
also, if we cho'e to consider it, would be inoperative with 



Jl'NE, 1904.] 



XOWLKDGi: .V SCIENTIFIC N i:\VS. 



121 



NORTH 









I- 

UJ 

3 



SOUTH 



^^ 



Photograph of a Group of Spots and of the GranulaLtions of the Solar Surfa.ce, 
taken at the Meudon Observatory, 1884, April 1, lOh. 46m.. G.M.T. 



122 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



a uniform temperature. At the surface, however, there 
will be a wide difference ; between the rapid loss by 
radiation and the rapid restoring currents from below, 
no permanent or equable balance can be maintained ; the 
slow currents from within, which tend to make their way 
outwards under the tendency of the bulk to settle down 
with greater condensation in its outward parts, here burst 
forth with a violence which all can see, and having 
parted with their energy, return nearly as precipitately. 
I Radiation, then, is the dominating factor in the distri- 
bution of temperature and density within the Sun, and 
it will be noticed that in showing it to be so no assump- 
tion has been made as to the law by which it proceeds. 
If we wish to put our conclusions in a numerical shape, 
such assumptions cannot be escaped. For example, 
Stefan's well-established law of radiation, according to 
the fourth power of the absolute temperature from the 
surface of a " black body," does not apparently permit 
any conclusions to be drawn as to the law by which a 
gas would radiate. Between imperfect physical know- 
ledge on the one hand, and mathematical difficulties on 
the other, nothing can be done except to produce a more 
precise illustration of the foregoing argument, and to 
show that the conclusions will stand scrutiny. This I 
have done in a paper published some nine years ago."" 

There are two other general problems presented by the 
Sun which appear to invite solutions upon general 
mechanical principles. The first of these is the eleven- 
year period in solar activity. But as to an efficient cause 
for it, or even any calculable phenomenon which could 
follow its phases in a similar period, we seem to be still 
quite in the dark. An attempt has been made to repro- 
duce such a period by a combination of tidal effects pro- 
duced by Jupiter and Saturn ; but the result is uncon- 
vincing, because the tide produced must be at most very 
minute, and the coincidence of period is dependent upon 
a hypothesis for which no reason can be assigned as to 
the relative intensity of effect of the two planets. In 
fact, we know as yet too little of the phases of this cycle 
to hope to theorise upon it successfully. Any real ex- 
planation must cover the more detailed description which 
Lockyer has given, to which allusion has been made 
above. 

The second problem to which I refer is the law of rotation 
of the surface, by which the equator of the Sun rotates most 
vapidly, and parts in lower latitudes rotate more rapidly 
than parts in higher latitudes. The law was discovered 
by Carrington from motions of the spots, and was at 
first believed to refer to the spots, but in the hands of 
M. Dun&r, the spectroscope has proved that the property 
belongs to the whole photosphere. If we do not mark 
off the photosphere from the rest of the body of the Sun, 
this law contains, I believe, no mystery. If we suppose 
that in the course of its condensation in the past the 
inner strata of the Sun were to be found rotating faster 
than those outside them, it can be proved that as soon as 
the body had condensed to a compact Huid consistency 
so that the internal friction of its relative motions came 
into play, a law of rotation identical with that exhibited 
in the vSun woulil deselop. But perhaps more striking, 
though less complete than a mathematical proof, is an 
illustrative experiment that was carried out some years 
ago by M. Beloposky, who filled a glass globe with water, 
carrying powdered stearin in suspension, and whirled it 
on a whirling machine until a uniform rate of rotation was 
taken up by the whole. The glass was then stopped and 
the motion of the water as exhibited by the particles in 
suspension was watched. The circumstances were now 

•Memoirs Royal Astronomical Society. Vol. LI. 



in substance just such as I have sketched above, and the 
apparatus exhibited just such relative motions as the 
Sun displays, individual particles travelling spirally from 
the equator towards either pole, with an angular motion 
which was less for greater latitude, ultimately passing 
inwards radially into the body. This last detail seems to 
convey also a suggestion of activities limited to special 
zones that may prove fruitful. 

Photograph of the Solar Granula-tions. 

In the accompanying plate we give a reproduction on a 
reduced scale of part of one of the magnificent photo- 
graphs of the solar surface, recently published by 
M. lanssen in the " Atlas," which we noticed in the 
April issue. The wonderful manner in which the 
minute structure of the solar photosphere is brought out 
in M. Janssen's superb photographs is due principally to 
the care which he has taken to secure two points — the 
one that the photograph shall be taken by light which is 
practically monochromatic, so that the image is as sharp 
as it is possible to obtain it ; the other that the exposure 
shall be extremely short, so as to accentuate minute 
differences of brightness in the most luminous portions 
of the disc. It will be noted that the photograph is so 
under-exposed that in the present reproduction the penum- 
bra;' of the spots are perfectly black. They were not 
absolutely featureless in the original, but were exceedingly 
faint, the darker portions of the sun being thus sacrificed 
in order to secure the maximum of detail in the more 
brilliant parts. The intensely granular nature of the 
disc and the thatch-like structure between the spots are 
very clearly seen. This particular region of the sun 
does not show any strongly developed instance of the 
blurring of the granules ; but here and there small 
smudged regions show themselves. 

The original of this photograph was taken on April i, 
1884, at loh 46"^ G.M.T. The group of spots in the 
centre of the field is the one numbered 1343 in the 
Greenwich series. It was a sudden outburst, the day 
of the photograph being only the second of its exist- 
ence. Its area at the time was 177 millionths of the 
sun's visible hemisphere, or slightly over 200 millions of 
square miles. The group increased in size with great 
rapidity. On April 2 its area was nearly five times as 
great as on April i, and l)y April 6 the group was one of 
the largest seen during the entire 1882-1884 maximum. 
It returned to the visible hemisphere on April 21. I )uring 
the thirteen days that it was under oliservation at this 
return, it was gradually diminishing in area; the leader 
spot being as usual a circular spot of regular structure, 
and much more stable than the rest of the group. Before 
the group disappeared at the west limb on May 3, the 
leader was the only survivor. The leader was seen again, 
still as a well marked circular spot, during two further 
returns. It slowly diminished in size, and was last seen 
on July 12, when it had shrunk to an area of no more 
than six millionths of the solar hemisphere. The entire 
life of the .group was thus 103 days. 

The scale of the accompanying photograph is one of 
^^ inches to the diameter of the sun. 



Mr. J. \V. Jarvis, l'\r,.S., St. Mark's College, Chelse.i, S.W., 
has been appointi-d Cl.iss Secretary and Class Treasurer to 
the London C.eolosical Field Class. The excursions this 
season are to Mcrstham on April 30, and to I'urley, Henley, 
Wimbledon, Aylesford, Leighton, liedford, Chislehurst on 
succeeding Saturdays. 



Jl-NE, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 




ASTRONOMICAL. 



Comet 1904. ' (Brooks). 

After an interval of seven months, during which no comet has 
been under observation in the northern liomisjihcrc, a now 
comet was discovered by Professor W. H. Brooks, director of 
the Smith Observatory, Geneva, U.S.A. The new object, as 
the following elements by Herr E. Striimgren will show, has 
almost exactly the same perihelion distance as the comet dis- 
covered by M. Giacobini, December 2, 1902. Only one other 
comet is known with a perihelion distance greater than these, 
namely, that of 1729. An examination of the Harvard photo- 
graphs taken before the discovery of Brooks' comet furnished 
six plates, showing objects which might possibly be identical 
with it. These were taken on March 1 1 and 15, and April i, 5, 
13, and 16. The first two places have not as yet been satisfac- 
torily included in any orbit, and possibly the images shown on 
these two plates do not in reality belong to the comet. The 
nebula; N.G.C. 6555 and 6564 are in the innnediate neighbour- 
hood of the place indicated by the plate of March 11. At the 
present time the comet is receding both from the earth and 
from the sun, and is slowly diminishing in brightness. This 
makes the twenty-fourth comet discovered by Professor 
Brooks. 

Elements. 

T = 1904, Feb. 28, 8130 M.T. Berlin 
u = 50° 51' 30" 



a= 275° 17' 3^- 

i = 124° 59' 38" 
logq = 0-42951 



1904-0 



Methods of Determining Jovian 
Longitudes. 

In the " Monthly Notices " of the Royal .Astroiioniical Society 
for March, 1904, Mr. Stanley Williams institutes a comparison 
betv/een the method of determining tiie longitude of markings 
on Jupiter by estimating the times when they appear to be 
exactly in mid-transit with the method of measuring their dis- 
tances from the two limbs of the planet Ijy a micrometer ; and 
he gives good reason for thinking that the first and simpler 
method is, in the hands of a practised observer, not at all 
inferior in accuracy to the latter. The micrometric method 
h.as been supposed the better from the comparison of measures 
of the s.ame object made on the same night ; oljviously transits 
of any object can only be compared ;is taken on difierent 
nights. Mr. Williams has in this paper compared micru- 
metric measures made of objects on different nights, and finds 
that they show no superiority in accuracy over the method of 
transits. 

* * * 

Change from Taurus to Aries as First 

Sign of the Zodiac. 

The same number of the " Monthly Notices " contains a paper 
by Mr. and Mrs. Walter Maunder, in which they show that 
there are clear indications in Assyrian records of two distinct 
methods having been in use for the determination of the begin- 
ning of the year. The earlier was that of the seleniacal setting 
of Capella. This involved the recognition of Taurus as the 
first constellation of the zodiac, and was no doubt in opera- 
tion as early as 2000 B.C. The second was the direct deter- 
mination of the equinox by some form of time-measurer. 
Other advances io connection with this seem to be indicated ; 



the recognition of the ecliptic as distinct from the equator; of the 
ascending node ; of the nature of the motions of some at le;ist 
of the planets; and the division of the ecliptic was elTeeted 
into twelve equal signs as distinct from the twelve irregular 
constellations. The dale when tlu;se changes took place 
cannot have been very different from tliat when tlie star 
Hamal, the briglitcst of the constellation Aries, marked the 
spring colurc, i.c'., about 700 B.C., and the remarkable out- 
burst of scientific activity which is thus indicated was in ;ill 
probability associated with the great literary activity of the 
reign of Assurbanipal. 



The Astrographic Catalogue. 

It is now seventeen years since the delegates of seventeen 
different nationalities met in Paris, under the presidentship of 
Admiral Monche-z, to consider the question of a photographic 
chart of the whole heavens, down to the stars of the fourteenth 
magnitude, with a catalogue of stars to the eleventh magni- 
tude. The latter portion of the programme is now beginning 
to be realised ; the Potsdam observatory has already produced 
three volumes of its catalogue; the observatories of I lelsingfors, 
of P.aris, and of the l-'rench colonies have also begun to pul)- 
lish ; and the Astronomer- Royal, at the meeting of the Royal 
Astronomical Society, already alluded to, presented the first 
volume of the Greenwich catalogue, covering one half the 
Greenwich section. The introduction to the catalogue con- 
tains a number of exceedingly interesting discussions ; of the 
effect of personality on the measurement of the places of 
stellar im;iges, of the probable error of the measures, and ol 
the determinations of photographic magnitudes. The accuracy 
of the measures of position are of the same order as of obser- 
vations with the transit instrument ; the probable error of the 
position of a star, in arc of a great circle, deduced from the 
measures on one plate is + o'26" in R.A., and + o'ZiS" 
in Declination. In the investigation of photographic magni- 
tudes, it was found that in passing from one exposure to 
another the law, exposure X brightness equals constant, held 
almost exactly, except in the case of the shortest exposures, 
which gave fainter stars than would be expected in accordance 
with the law. 



Distribution of Stars of the Third and 
Fourth Type. 

In a discussion of the distributiun ul'the coloured stars, Ilerr 
Freidrich Kruger gives in the " Astronomischc Nachriehten," 
No. 3947, a table dealing with 3>Soo stars of the third and 
fourth types of spectra. These are distributed into eiglit 
zones, each twenty degrees in breadtli, the galactic eijuator 
running through the middle of the fifth zone. The table shows 
that about 4 per cent, of the stars of the third type of spec- 
trum are known to be variable, but 14 per cent, of the fonrth 
type. Both cluster towards the galactic equator, but tliat 
clustering is nuicli more evident with the fourth (ype stars. 
These two relations were drawn attention to by Professor 
Hale in his recent " Memoir on Stars of the h'ourth Tyi>e." 
A curious point of difference between the two types is shown 
by Herr Kruger's table, namely that whilst tlie numbers of the 
third typi: show but very small increase with diminution of 
magnitude, the faintest class of the fonrth type includes more 
than all the other six classes combined. 



The Spectroscope Binary, Iota Pegasi. 

Professor W. \V. Campbell discovered in i'-ii)9 llial Iota 
Pegasi was a spectroscopic binary, and Mr. Heber D. Curtis, 
from a very thorough discussion of forty-three photographs of 
the spectrum extending over six years, has obtained very 
accurate final elements for it. The period found is 10-21312 
d;iys, and the velocity — 4- r2 kilometres. The orbit is nearly 
eiicular, the eccentricity being o-oo«5, so that the epoch of 
periastron is not very certain. Dr. R. G. Aitken examined 
the star in 1901 with the 36-inch refractor of the Lick 
Observatory, but was not alile to detect any evidence of 
duplicity. 



124 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



The adaptation of the Forty-Inch Visual 
Refractor of the Yerkes Observatory 
to Photography. 

In till' original design of the forty-inch refractor of the 
Verlies ( )bservatory, no provision of any Uind was made for 
direct photography ; there is no gniding telescope to enalile 
lengthened exposnres to be given, nor photographic corrector 
to firing the actinic rays to a focns on the sensitive plate. 
Mi. (i. 'I'. Ritchey has overcome the first difficnlty by means 
of an eyepiece magnifying abont one thons.uid diameters, 
placid in the side of a donble slide carrier. A small diagonal 
prism receives the light of the gniding star, and refiects it at 
right angles into the eyepiece, and this with its accessories 
are monnt<'d on a slide which can be moved to any desired 
position on tlie upper side of the rectangular bo.x, and firmly 
clamped there, so as to assist in finding a suitable guiding 
star. The star is brought to the intersection of the cross-lines 
in the ejepiece, and is Uept there throughout the exposure of 
the sens live plate. The observer sits with his eye at the 
gniding eyepiece and his fingers on the two screws which 
move the slides, and thus he introduces any minute correc- 
tions of position which he sees are necessary. These correc- 
tions may be on account of either the irregular movementsof 
the driving clock of tlie telescope, or more frequently from the 
tremors in the atmosphere. The latter irregularity may 
reipiire correction several hundred times in a minute, and a 
practis-'d ob.=erver can introduce between one and two 
hundred per miunte. The other difficulty — that the instru- 
ment is a visual one — Mr. Kitchey has obviated by the n.se of 
a delicately tinted yellow screen. This screen utilises the 
ravs of light which are most freely transmitted by a large 
objective; since it is a well Unown fact that while only a 
small percentage of the yellow rays are lost by transmission 
throirih a Large and necessarily thick ol)jecti\e, a veiy large 
percentage of the blue rays are. Consequently the forty-inch 
visual objective, thus used with a yellow screen, and plates 
sensitised to the yellow rays, is scarcely less rapid, if at all, 
ni photographing stellar images, than an ofiject-glass cor- 
rected for blue rays would be. In two hours it registers stars 
of approximately the seventeenth magnitude, which are at 
the visual Hunt of the instrument ; and in five hours can 
register stars of a magnitude fainter. The yellow screen is 
formed from two tliin and transparent plates, finely ground 
flat and highly polished. One of these plates, wliich are S by 
10 inches, is flowed over with a collodion film of a delicate 
yellow tint, and when the film is dry, this is covered with 
Canada balsam, and the other plate bound on it as a cover 
glass by adhesive tape. When in use it is laid close upon 
the sensitive plate, nothing separating them but the tape. 
Mr. Ritchey has been most successful in photographing por- 
tions of the moon's surface, and close clusters of stars, and 
in Vol. VHI. of the Decennial Publications of the University 
of Chicago, several very fine specimens are given, notably one 
of the lunar cnitcr Theophilus and its surroundings, which 
perhaps shows the detail on the moon's surface more clearly 
than any otlicr photograph ever taken. In the photographs 
of the clusters Messier 13 and 15, the original neg.itives and 
transparencies from them show the star images separ.ite and 
distinct, even at the very centre of the cluster, but in the pro- 
cess reproductions given in the volume the smaller and nearer 
stars are mi^rgcd together. With nebula; the yellow screen is 
not so successful since these are lich in their proportion of 
green rays, which do not come to the same focus as the 
vellow. 

■«• * * 

Photographs with the Two-Foot Reflector 
of the Yerkes Observatory. 

Seven very fine specimens of Ihc woi k done with the two- 
foot reflector of the Yerkes ( )bservatory are published in 
Vol. VIII. of the Decennial I'nblications of the University of 
Chicago. These are of the two giant nebula- of Orion and 
Andromeda ; of the spiral nebuhe Messier ;5 Tiiangnli and 
Messier 51 Canum Venaticoriin ; of the c.irded-wool-like 
nebulosity in the Pleiades; and of tlie torch-like nebuhe in 
Cygnus known as N.G.C. 6960, and N.G.C. ht)i)>. These two 
last form part of the same extended nebulosity, but they 



present some striking differences in their relationship to the 
stars. In the first ease the nebula seems to act as a wall or 
barrier separating a region strewn very thickly with stars, 
from a sparser field ; in the other case no such difference in 
the numlier of the stars seems to exist on the two sides of the 
nebul.i, which itself appears to lie in a district of few and small 
stars. 



'i^<ti^t^(ti 



ZOOLOGICAL. 



Mosquitoes in England. 

Di'Siu rr; the coldness and wetness of the season, mosquitoes, 
according to the " Report on Economic Zoology," issued by 
the Trustees ot the f-Sritish Museum, .appear to have been 
unusually numerous in England last summer, and to have 
caused much annoyance and inconvenience. They were 
■\cry prevalent in parts of b^ssex, especially in the neighbour- 
hood of hipping I'orest, and also in Kent and Surrey, notably ■ 
along the \allcys of the Thames and the Kennet, and in the 
marshes bordering the lower courses of the Thames and the 
Lea. They were also reported as having caused much annoy- 
ance near Bristol, at Great Staughton, Huntingdonshire, and at 
Weston-super-Mare, Worplesdon, Colchester, Canterbury, 
and Birchington. Although complaints of mosquito bite are 
received almost yearly from the Thames Valley, last summer 
the in.sects in question .seem to have been unusually virulent, 
causing such swellings that medical attendance was in soiiie 
instances recjuisitioned. The species most abundant were the 
conmion gnat [Cithx pifticm) and the banded gnat {Tlicubalilin 
auniiUitii), the latter of which does not usually attack man. This 
reminds us that we fail to see the reason for dropping the 
good old English word "gnat" in fa\our of the foreign 
'" uioS(]uito," now th.il both are known to be the same. 

■X- * -X- 

A Deer-like Antelope. 

Hitheito there has been supposed to exist a sharp distinc- 
tion between deer and .antelopes, according to the nature of 
their horns ; but recent discoveries iu North .America tend to 
show that this distinction is only a fcatnre of the present day. 
Deer, it is almost superfluous to mention, have deciduous 
bony antlers, while in antelopes the horns are covered with 
hollow sheaths, which are never shed and never branched. 
The .American prongbuck resembles antelopes in its skeleton, 
but its horns are forked. The new fossil type combines the 
skeleton and teeth of an antelope with the antlers of a deer. 



New British Mouse. 

According to a note by Mr. W. IC. Cl.irkc inthi Proceedings 
of the Royal Physical Society of Edinburgh, the mou.se of the 
l-";croe Islands is a large and stouter built animal than the 
rommoii house mouse, from which it also differs in colour. 
It is therefore regarded as representing a distinct local race 
of that species. St. Kilda has also a pecnli.ir mouse of its own. 



A Rare Bird at the Zoo. 

The Zoological Society's menagerie in the Regent's Park 
has recently received an interesting and valuafile addition in 
the form of a specimen of the South American boat-billed 
stork {Citiuhroiiui cochhnr'ui). It is many years since this 
species, which, by the way, must not be confounded with the 
shoe-bill of the White Nile, has been represented in the 
collection. 

•>;■*» 

New Egyptia-n Fossils. 

(ircal interest .attaches to the dcscri|ition by Dr. Fra.is, of 
Stuttgart, of certain very remarkable fossil niammaliau 
remains from Lower Tertiary marine strata in the Mokattam 
range, near Cairo. These specimens serve to show that a 
gigantic Tertiary whale-like creature, known as Zcui^kniun 
(of which the remains were first discovered in North America), 
is the direct descendant of the primitive land Carnivora of 



June, 1904.] 



KNOWLEDGE cS: SCIENTIFIC NEWS. 



125 



the eaily Tertiary: the nowly-discovorcd tonus bciiii; 
actually the inissinj; links. Hitherto, /cii-^hhiini itsrHhis horn 
•jnuT.ilK los^.inifd as an aiicestr.il ty|H' of wlial.-, Iml lliis. 
accorilins; to Dr. Kiaas, is incorrnt ; lliit criMtiirc, .illlioM^li 
mariiu', liavinj; no sort of allinily willi the Ci lacci. It this 
be fo, we have still other niissiiij; links to disiovi 1. iiaim ly. 
the progenitors of the latter ponp. 



Fish Scales. 

We may now, it seems, ascertain the a.s^c- of the co<l and 
haddock sent to ns by our fishmonger by the examination of 
their scales. For it appears, aceordinii; to recent rese.irciics, 
th.at the scales of these fishes, like those of carp, d<\< lop at 
intervals certain well-marked rings, which appear to indicate 
the limits of the annnal growths. 



An American Hedgehog. 

The discovery in the middle, or Oligocene, Tertiary deposits 
of Dacota of the remains of an extinct specitsof hedgehog may 
not appear to non zoological re.aders a matter of nmch ini 
portance. In reality it is ,a fact of the v< ry greatest interest, 
for hitherto the hedgehog tribe {liiiiuucidu) has been regarded 
as an exclusively Old World group. The discov('ry of the 
fossil .American species (which has been made the type of a 
new genus, under the name of Pnttluiix, and is described in 
the xixth volume of the HulUlin of the .American Museunii 
serves to strengthen the view of those who maintain that thi' 
northern coimtries of both the Western and ICasleni Henii 
spheres form but a single zoological region ; .and th.at formeily 
there was comparatively free conmiunication l)etwecn llicm in 
the neighbourhood of Hehring Sea, under climatic conditions 
which permitted of temperate forms passing from one conti- 
nent to the other. When we know ninreof th<' Tertirny fauna 
of Eastern Siberia, it is probable that the number of groups of 
animals confined to one or the other JKniiisphere will be still 
further diminished. 



Fish Destruction by Birds. 

At a recent meeting of the I'lella.-I Natural Ili-tnry and Philo- 
sophical Society, Mr, J, l>rown gave reasons for concluding 
that there are 2,000,000 gulls in the I'nited Kingdom, and that 
duriog the herring season each bird destroyed 200 fry per dav, 
or i2,(X)o during the two months of the sea.son. These, if they 
had come to maturity, would h;i\(' been worth /"24,ooo,ooo. 
He, therefore advocated the di^struction of the gulls, each of 
which cost the nation /'12 in two months in consequence of 
their protection by -Act of parliament. If we add to the dam- 
age done to herrings by gulls tlu' loss inliicted on these and 
other fishes by cormorants, shags, gannet:-', guilU-mots, Xc, 
there can be no doubt that the supply of food fishes is enor- 
mously (bminished ; and it seems little short of folly to be 
spending vast sums of mone)' on the m.iiulen.ance of fish- 
hatcheries at Piel and other places, and at the same time to 
do all we can to ensure the destruction of valuable fishes 
by encouraging the increase of their natur.il enemies. I->irds, 
are, no doubt, charming adjuncts to scenery — both on tin; 
coast and inland — but such ornaments may be bought too 
dearly. 

■k * * 

The Destruction of Whales. 

In the course of a \ ery iuleresting |)a|)iT on whales and 
whaling contributed to llie April number of the Annals oj 
Siollisli Sdtiiral lUstorij, Mr. T. .S jutliwell tells us that whereas 
between the years i.Si.( and 1.S2; no less than 12,907 Oeeu- 
land whales were killed olf Greenland and in Davis Straits by 
British vessels, only 127 were accounted for in the ten years 
ending with 1902. Comment is superlluous. 



Papers Read. 

At the meeting of the /nological Society, heUl on April 19th, 
Mr, O. Thomas exhibited the skull and skin of a h.artebeest 
from Uganda, which were regarded as representing a new 



species; and .also skulls of the North .Australian rock-w.illabv, 
a s^pecies rem.arkable for developing an unusually Large sc-rie-i 
of molar teeth, whioli are eonliniiously slieil .uid renewed. 
This s.une geulK-m.ui, in coll.d)oiMtion with Mr, Schu.iuii, 
n-.ul .1 p.iper on trteutyoue species of mauini.als eollirteil 
during the work ol the Hoinid.ir\' C'oiuniission between I'lrilish 
and Ciermau l-^ast .Africa, of which three were reg.irded as new 
to sci(Uice. Mr. liedd.ird contributed the second instaliu<'nl 
of a series of papers on the anatomy of li/artls, dealing in this 
inst.ince with the South .Anieric.in leguixin; Mr. ISonlenger g.ivc 
addition.d information with regard to the skeleton of the ixtinct 
Scots reptile I lU-ifclnin ; while Dr. Uroom described the sti uc 
ttire and mode of articulation with tln' fkiill of the lower |.i\v 
of some of the extinct mammal like reptile^ of South .Abica. 
l'"in;dl\', Mr, Druce gave descriptions of three-aud-tvvcnty le-w 
South American butterfiif s. At the meeting of the same bodv 
on May 3rd the following four p.ipers were re.id, n.iimU' : Mr. 
'I hom.is on the osteology .and systematic imsition of llu- 
M.dagasy bat .Wvve/'di/i; iinrilii ; Mr. Beddard on c 11 l.iin 
features in the vascular system of ch.amcli-ons and other 
li/ards; Mr. .A. D. Iniins on the gill r.ikers of the sturgeons 
of the genus Patyihlon \ .lud |)|. Kideudod on the skulls of 
cert.ain bou\' fishes. .A sketch was exhibilcil ol a young 
.African eleph.ant rem.irk.-ible for the .■unoinit ol h.iir on ils 
body; and .1 |)liotogr;iph was shown of the last <)ii.igg.i living 
in the menagerie. .At the Cicolo'^icd .Socii'ty on .April ^ytli. 
a new species of fossil scorpion from thi' (d.diueasure-; of 
L.auc.-ishire was described by Messrs. Baldwin .lud Siilc lille. 



Mr. W. Koyal-D.awson writes; — With reference to the Note 
in last month's " Knowi.i-.dgi- " ip. ijfi) on the prior oiieuing of 
the right eye, I may state that out of a litter of eight t;ime 
whit(; rats born a short time ago no less th.in seven opened 
the right eye first, while the eighth showed no lenden(;y to do 
so. I think this will suffice to confirm the su]iposition that 
the right eye is the first to be opened in the order Ro.tcnt'ui. 



%^^'i'i^ 



BOTANICAL. 



An ;disfr.icl of Mr. (i. Massee's interesting [iiper "On the 
Origin of Parasitism in h'uugi," which has r('C(nitiy been pub- 
lished in full in the I'/iilnsa/'Inial I rtinsntlinns of the Royal 
Society, is given in the Society's Procccdini^s, ;ind also in the 
Annuls 0/ lUiliin;/ for April. The author explains why it is 
that a certain parasitic ftmgus is often only eap;ible of infect- 
ing one particul.ir species of plant. Though the spores of 
these fiingi germinate freely on the sutface of any pkint when 
moist, inlection is confined to the particul.ir species of pl.iut 
which is the usu.al host of the p.ar.asite. This sel'_cli\e power 
is .atlriliuti d to chemolaxis. The presence of sacehajosi; in 
the cell sap of the' host plant is found to induce iuleclion by 
many sapioph)lic ;uul par;is tic fungi, unless Ihe inlbieuce of 
this .itli active or posit i\ely chemotaclic substance is overcome 
by the presericc of a more powerbil negatively cheniotactic or 
repellent substance. Apples, though eout.iiuiug siceharosi, 
are immune Irom the attacks of I'ntiytis luicri-ii, which pre_\ s 
on a greater number of dilfi'reul pkmts lh;iu any olhi-r known 
par.isitic s,,(;cies. This ininumity is due lo the presence of 
malic acid, which is repellent or neg;itively cheniotactic lo 
the germ lubes of this particular fungus, l^xperinieuts havc^ 
shown that a fungus can be induced to attack the leaves of a 
pl.int, on whic-h it is not ordinarily parasitic, by injecting into 
them the subst.aiice which is known to be jiositivcly eheme- 
faetic to its germ tubes. 

In the Annuls nj Ilaliiny for .April, Mr. J. P.ukiii c.ills ;itl<'U- 
fion to the nectaries on the bud-scales of the Para Rubber 
tree, llcvca hnisilicnsis, apparently the only plant that pos- 
sesses them on these organs. The l'"uphoibi;ice;e, to which 
llivi-a belongs, contain numerous species in which extra-fior.il 
nectaries ;ire jireseut, usually on the stem or on thi^ l.iniin.a or 
petiole of the leaf. Ilci'ca akso has them on the leaves, and 
various n-ferenccs to these have been made by writers, but 
the nectaries on the Inid-scales seemed to ha\e been over, 
looked altogether. This is probably due, as the author 



126 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



explains, to the fact that an adult tree of the Hcvca " puts forth 
fresh foliage annually, and the bud-scales being caducous, 
are merely evident while the shoots are in the immature con- 
dition." The honey secreted by the nectaries encourages the 
visits of ants, whose presence assists in safeguarding the 
developing foliage from the attacks of injurious insects. 

PHYSICAL. 



The Emanation from Radi\im Bromide. 

Til show the diltusion of the cuianation from radium bro" 
niide. Mr. T. Indricson, in a paper recently read before the 
Russian Physico-Chemic.al Society, used a long tube, the in- 
ternal surface of which was coated with a layer of zinc- 
sulphide. On connecting the apparatus with a test-tube 
containing a solution of radium bromide, luminescence was 
found to appear and to be prop.agated throughout tlie tube. 
On rcpc.iting Ramsay's experiments, the author found that 
the yellow helium line did not coincide with the yellow lines of 
the spectrum given by the emanation, but was situated between 
the two yellow lines of the emanation. When the serpentine 
coil conununicating with the tube was dipped into lir|uid air. a 
strengthening of the lines corresponding to the helium line was 
noted in the spectrum of the emanation, while between the 
two yellow lines above referred to a third line, coinciding with 
the yellow line of helium, appe.ai-ed. The lines of helium do 
not exist in the spectrum given by the emanation of a freshly- 
prepared tube, but only appear afterwards. On observing the 
gases set free on the dissolution of radium bromide, it was 
observed that the helium lines did not appear as long as the 
spectrum tube preserved its phosphorescence in the dark. 
After four days this phosphorescence would disappear, and the 
lines of helium could be noted in the spectrum. — A. G. 
* * * 

Action of Ratdium on Metals. 

In order to investigate the action of radium on metals, 
N. Orloff, as pointed out in a paper recently read before the 
Russian Fhysico-Chemical Society, covered, in April, 1903. an 
ebonite capsule containing 0-03 gm. of radium bromide with 
an aluminium plate o'oi mm. thick, instead of the mica gene- 
rally used. In the course of July the author, on opening the 
capsule, noted on the surface of the aluminium turned 
towards the radium some protuberances of the same aspect 
as the surrounding surface of the aluminium, and resembling 
small drops of melted metal. These protuberances proved to 
be radio-active, producing a photographic image on acting for 
some minutes through bl.ack paper : and even after six months 
they were found to emit invisible radiation without any appre- 
ciable weakening. The author thinks that a stable alloy is 
formed by the accumulation of material particles given off 
from the atomic systems of radium, around small aluminium 
nuclei. — A. G. 

•* ■» * 

On Radio-Active Ennanation from 
Water and Oil Fountains. 

In a paper published in No. S of the Physikalischc Zcitschrijt 
(April 15, 1904), Prof. F. Himstedt arrives at the conclusion 
that radio-active bodies giving off a gaseous emanation are 
widely diffused throughout the earth ; these emanations are 
absorbed by water or by petroleum, and after having been 
conveyed along with the latter to the surface of the earth, will 
thence diffuse into the air. Because of the many analogies 
noted between these emanations and radium emanations, the 
author thinks it possible that both are identical. In this case 
the ores of uranium, from which radium emanations are de- 
rived, would either be widely diffused or else there would be 
some further matters possessing, though to a lesser degree, the 
property of giving off emanations. Considering that the ab- 
sorption coefficient of water, as well as of petroleum, with 
respect to this emanation, is found to decrease for increasing 
temperatures, while hot fountains, on the other hand, show an 
especially high activity, the hypothesis is suggested that the 
amount of radio-active mineral increases with increasing 
depth. The radio-active components of the earth should, 
therefore, possibly be allowed for in estimating the tempera- 
ture of the earth's mass. — A G. 



ORNITHOLOGICAL. 



By W. P. PvcRAFT, A.L.S., F.2.S., M.B.O.U.,&c. 



Gloss ylbis in the Orkneys. 

The "Annals of Scottish Xatnnil History " for May contains an 
account of a Glossy Ibis, Ibis Jnlcindlus, shot a mile west of 
Stromness on September 19 last. According to Mr. Eagle 
Clarke this is only the second occurrence of this bird in the 
British Islands, the first having been shot in iSjy near Kirk- 
wall. Some mistake has certainly been made here; for which 
Mr. Eagle Clarke can hardl\- be responsible. So good an 
ornithologist doubtless knows that at least thirteen instances 
of its occurrence in Great Britain are recorded, one of these 
being from .Vberdeen-shire — October 4, 1880. According to 
Mr. Ussher there are no less than twenty-two instances of its 
occurrence in Ireland. 

* * •* 

Rough-Legged Buzzard in Co. Down. 

The Rough-legged Buzzard. iUitm tiii^opns. is only a rare 
visitor to Ireland. According to the Irish iS'iitnralist (May) 
a specimen v/as shot in November last in Co. Down — 
the fifth in Down. This appears to be the tenth recorded 
instance of its occurrence in Irish territory. 



Stone-Curlew: Co. Donegal. 

An example of this rare visitor to Ireland was obtained on 
< )ctober 12 last in Co. Donegal. This is the first time of its 
occurrence in Donegal. Only ten other cases of its occurrence 
in Ireland are on record, and eight of these, it is interesting 
to note, were obtained on the East Co.ast. 

* * * 

Ravens Nesting in Captivity. 

Instances of ravens breeding in captivity are rare; and 
cases of successful rearing are still more so. Mr. W. H. 
St. Quintin's note in the Field (May 7) to the effect that he has 
in his aviary a pair of young that are nearly ready to leave the 
nest is therefore of considerable interest, especially so having 
regard to a certain police court prosecution which took place 
some time ago. 

* * * 

Great Crested Grebes at Richmond. 

Mr. Gordon Dalgliesh sends us some interesting notes on a 
pair of these birds which he has had under observation since 
April 17 last. They have taken up their quarters in the Penn 
Ponds and appear to be breeding. When preening the breast 
feathers, he remarks, these birds turn over on to their backs 
and do not perform this operation when sitting upright as one 
would imagine. " The female, when she landed, did not stand 
upright, but dragged herself along on her belly." 



Colour, and Coloration in Birds. 

An extremely interesting and important paper on this sub- 
ject was read by Mr. T. Lewis Bonboteat the Linnean Society 
on Ma}- 5, to which we hope to be able to refer later. 
Briefly, he contends that bo;h colour and coloration are prim- 
arily due to physiological causes, and that the varied patterns 
and tmts of plumage which distinguish different species are 
determined by the action of natural selection on these " ex- 
pression points " of "vigour." 

There is an intimate connection, he contends, between the 
bleaching process which takes place previous to moulting, and 
the development of conspicuously marked areas. These in- 
deed, he holds, are nothing more than permanently fixed 
bleaching, or intensification areas, which he terms " pitcilo- 
meres." 

Messrs. Newton and Co., who have held appointments to 
the Royal Family continuously since i860, have this week 
been honoured by a Warrant of Appointment as Scientific 
Instrument Makers to H.R.H. the Prince of Wales. 



June, 1904.] 



KNOWLEDGE e^- SCIENTIFIC NEWS. 



127 



Ba^cteria and RoLdio- 
Activity. 

By the kindness of Pr. Al.in (irccn wc are aMe to repro- 
duce two photot^aplis sliowins the effects that liactcria wliich 
have been snlniiittod to the action of radium lironiidc, produce 




Tuberculosis hacilli. 

on photographic plates. Small masses of bacterial growth were 
exposed to the li and -, rays of 10 milligramiiies of virtually pure 
radium bromide. In a large number of inst.uiccs such masses 
when removed from the influence of tin; radium and placed 
between two thin sheets of glass, themselves 'not radio-active, 
were capable of so affecting the sensitised film nf a photo- 




graphic plate with which they were brought in contact that, on 
(levelopment in the ordinary way, the platfi showed a dark 
area corresponding to the shape of the l)acterial mass. The 
photo-actinic rays proceeding from the bacteria which had been 
exposed to radimu were capable of affecting a photographic 
plate through a double layer of lead foil. The rays thus 
(Miiitted seem to coincide with the ;:f rays of radium, for they 
are slopiied by a suOicieut thickness of lead. If any 7 rays 
are emitted bv the bacteria they do not appear to affect the 
photographic plate. It will be remembered that some years 
,igo Or. Johnstone .Stoney remarked that the microscopic 
dim(Misions of bacteria might lie due to the necessity of 
deriving their energy from the slower moving molecules of 
substances with which llii^y were in contact, and more lately 
il hasbfcn suggest(;d that the energy of radium might be due to 
th(! .ni.dogous power of that element to derive ils <'uergy from 
outside som-ces by sifting out the molecules of different speeds 
impiTiging on it. This theory, now recciveil with Ic^ss uu.ini- 
mity than the Kutherford-Ramsay-Soddy theory of the dis- 
integration of the atom, is neither confirmed nor disproved by 
Or. Al.in Creen's experiments, which appear to show thai 
bacteria, so far as ac(|uired radioactivity iseoueerne<l, beha\e 
like other substances. ( )ne of our jiholographs shows the 
blur made by a mass of tubercle bacilli on a plate; the other 
the elfect similarly produced by anthrax spores. The .acquiicd 
radio-aclivitv lasts in some instances for over six weeks. 

A Stereoscopic Single 
Lens. 



A Ni;\v method of obtaining stereosco|nc photographs, .and 
stereoscopic effects when looking at them, has been designed by 
Or. M. Von Rohr, of the Carl Zeiss firm. Its peculiarity is 
that the effects are obtained by a single lens directed at single 



Spores of Anthrax. 




Viewing througli the Single Lens Stereoscope. 



I 28 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



photographs. The photographs are taken with olijectives of a 
focal length below that of the range of distinct vision, which in 
normal sighted people is about ten-and-aquarter inches. 
Such a photograph viewed in the ordinary way wonid appear 
to 1)0 out of perspective and its parts out of proportion, thougli 
.some of this impression could l)e to some extent removed or 
remedied by magnifying the photograph. 

The accomp.inying figure indicates a method Ii\- which the 




Single l-ens Stereoscope, with Photograph.*;. 

ej'e can obtain a virtual distance-image magnified of the 
photographs. The apparatus will, in the case of normal 
vision, bring the different parts of the photograph under the 
same visual angles as those obtaining at the moment of photo- 
graphic exposure. ,\n achromatic magnifying lens is u.sed, 
the focal distance of which is similar to that of the objective 
used in photographing the object, and which is free from dis- 
tortion for objects situated at i ,', inches from the nearest lens 




Fig. 3 (Single Lens Stereoscopy). 



surface. The lens (fig. /,) is fiee roni astigmation but not from 
curvature of field. Therefore when using it the accommoda- 
tion of the eye nnist be altiirc^d accoi'ding as the central part 
or the m.irginal part of the photogr;i])hic print isunderinspec- 
tion ; and the nature of the eye accouunodadon will v.iry for 
short-sighted, long-sighted, and old-sighted people. Hut if all 
the directions arc carefully followed, an eye ot normal vision 
will j)erceive through tlu'lens, not the photograph as it appears 



to the unaided eye, but a far distant im.ige of it, free from dis- 
tortion, and under the same conditions of apparent size, dis- 
tinctness, perspective, light and sh.ide as those under wliich 
the objects themselves would be .seen with the short photo- 
graphic objective that has been mentioned. Consei|uently 
the small photograph thus conveys to the eye a much more 
natural effect than a landscape photograph can possibly do; 
and unconsciously the vision forins in the mind a correct per- 
ception of relief and dist.mces. Thus although the stereo- 
scopic effect is not of the s.ime kind as that produced in ordi- 
nary stereoscopes, the effect of solidity- is strongly evident 
and perceptible. A.(.i. 



"Osprey" Plvimes, Real 
and "Artificial." 



By W. P. PvcRArx, A.L.S., F.Z.S,, \c. 



Without doubt the most beautiful of feather orna- 
ments is that commonly known as the " Osprey " plume. 
Mow this name came to he used is a mystery, for the 
feathers in question are not obtained from the ( Isprey, wliich 
is a bird of prey, but from various species of Herons, those 
known as " Efjrets " furnishing the most hif^hly prized 
varieties. It is from the French form of this word l^gret, 
that the term " aigrettes," often used instead of " O.sprey," 
is derived. Naturally, the possibilities of these plumes 
as head-dresses, both for men and women, have been 
widely appreciated. Only in the Army, however, have 
they been worn by men in this country, and the practice 
has now been happily abolished. To induce our country- 
women to follow this lead, the most strenuous efforts ha\e 
been made within recent years to spread a knowledge of 
the consequences which follow from the encouragement 
of the traffic created by their demands. Though at last 
there seems some prospect of success attending these 
efforts, unless progress towards tliis end is more rapid, the 
extermination of the hapless victims is inevitable. 
This in itself would be an end much to be deplored, but 
the nameless suffering and pain, which accompanies this 
extinction, makes the "passing of the Egret" a pitifully 
sad story. 

To many women the broad outlines at least of this 
matter are already well known, and, as a result, numbers 
have decided to leave such ornaments severely alone. 
( )thers, unable to break the spell wielded by these seduc- 
tive plumes, have compromised, by forswearing what 
they believe to be real "Ospreys," and wearing, instead, 
what they fondly imagine to be an artificial product. 

In purchasing " Ospreys," at least in most milliner's 
shops, whene\er scruples are manifested, the assistant 
professes to ha\e doubts about the genuineness of tlie 
plume, retires to the Manager, and returns, assuring the 
anxious customer that a mistake has been made, that, 
after all, the plume is artificial. This fact, long known 
to the authorities at the British Museum, was shame- 
lessly admitted, only a few days ago, by the Manager of 
a large shop in London. " But ladies," he remarked, 
" arc hard to please, . . . Their consciences have to 
he soothed, and the assistant, rather than lose valuable 
custom, readily sells the article as artificial ! " 

In the wholesale trade the word artificial appears to 
ha\ e been used in a technical sense, long before the agita- 
tion against the wearing of "Ospreys" began. Inferior 
" ( )sprey " plumes and feathers of birds other than Egrets 
or their allies, which have been disguised to simulate 
" Ospreys," ofe known by the wholesale buyers as 
'' iiiiififKih." 



Jl-NE, 1904.] 



KNOWLEDGE .'t SCIENTIFIC NEWvS. 



129 



Hut let It bo (Jistiiutiy uiulerstooi.1 that the assertion of 
the retail milliners, that the plumes sold hy them as arti- 
ficial are made of quills split up, or of whalebone, or of 
any other material, are absolutely fiilsr. 

The broad facts concerning " Osprey " or " aigrette " 
plumes and their origin are briefly these. The " aig- 
rettes '" of the milliner are the long, loose, waving plumes 
taken from the backs of different species of small 1 leroTis, 
the white plumaged species, some ten in number, being 
the most \alued. The finest kinds are ttiose from the 
Little Egret, Garzetta garzetia, and the Black-footed 
Egret, Garzetta iiigripes. In both species the plumage is 
pure white, and the long " train" feathers are of a pecu- 
liarly loose, flowing type, of great delicacy, and recurved 
at the tip. It is this latter peculiarity that gives them 
the peculiar value. The little ICgret occurs in Southern 
Europe, China, and Japan, S. I!urma, India, Ceylon, 
Malay .\rchipelago, and Africa. 




Fig. I.- Three plumes of a whte E^rct. G:ir:c:lJ i;nrr.,tl:i, used for the 
purpose if making "ospreys" or "aigrettes." Note the extreme 
length and slenderness of the "barbs" or thrcad = Iike branches of 
the feather. 

The black-footed species has a more restricted distri- 
bution, being found only in Java, the Molluccas, and 
Australia. 

A third species, Leucophoyx candidissima, also produces 
recurved plumes, but these are not so fine as in the 
two just enumerated. This bird occurs in temperate and 
tropical America. 

In all the species on which this war is waged, some 16 
or 17 in number, these feathers are of great length. In 
some — e.g., Mesophoyx intermedius — they may attain a 
length of 17 inches. From a bundle of such, as many as 
four separate plumes could be cut. The delicate ter- 
minal portions of the feathers furnish the " genuine 
Osprey " of the wholesale trade, and fetch a high price ; 
whilst the three lower segments are sold as " artificials " 
often at a ridiculously low price — so low that it has often 
been contended that they could not on that account be 
real feathers. But the tips pay for the whole bundle and 
leave a profit ; the lower portions of the feather, there- 
fore, may well be sold cheap. 

Besides the w'hite Herons — some ten species in all — 



llutic aie MjMUil others laid under contribution. These 
birds are of varied colours, and the plumes are sold as 
" red " or " ash " Ospreys, and so on, as the case may be. 
But "artificials" are manufactured, in a sense, by 
manipulating the feathers of birds other than Herons, so 
as to produce what is at best a crude resemblance to the 
real plume. Probably the majority of these are made of 
what are known in the trade as " Vultures' " feathers, 
which are really the quill or " fiiglU" feathers of the 1\ hea or 
South American Ostrich. The method of preparing them 
is interesting. The shaft of the fjuill is split down the 
centre, so that one half of the "vane" of the feather 
adheres to each half of the stem (fig. 3). By spirally 
twisting this stem (fig. 4), the barbs forming the right or 
left side of the " vane " of the feather are made to form 
a series of long, slender filaments spirally arranged 
around a central shaft. The efTcct produced, though 
graceful, is really quite difTerent to that of the " Osprey" 
(fig. i). Moreover, tlie whole plume is hea\ier in 
appearance. I'eathers so treated are sold as artificial, 
and there is enough truth in the statement to be really 




Fi^. 2.— An osprey plume as sold at the milliners. In this case the 
plume has been dyed black. It is made up of two portions— a few 
valuable tips stuck into a bunch of stumps— i.e., "ligret" plumes, 
from which the tips have been removed. 

dangerous — dangerous inasmuch as whether sold as 
artificial " Ospreys " or as " Vultures' " plumes, the 
slaughter of Kheas is encouraged. Indeed, theextinction 
of this bird, in a wild state, seems to be rapidly approach- 
ing. Annually slain by thousands for the sake of its 
feathers, this Rhea has already been extirpated from 
much of country it formerly inhabited. That this 
should be so is deplorable, for the Rhea is a bird of the 
utmost scientific interest and importance. 

An equally crude imitation of the real " Osprey " is 
made by treating Peacocks' feathers in the same way as 
that just described in the case of the Rhea. 

But obviously the stump ends of real Egret feathers, 
or the split and spirally twisted feathers of the Rhea and 
Peacock, cannot he called artificial feathers. But what is 
one to do ? some of my readers may ask. How can the 
Egret feathers be distinguished from those of the Rhea 
or Peacock ? Do not try. Firstly, this is the work of 
an expert ; secondly, the sale of the imitation " Osprey " 
does but encourage the slaughter of another species. If 
the Egret is spared, the Rhea must die. 



I30 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



It should be made a punishable offence to sell feathers 
under the desi,L,'nation of " artificial," for thereby incal- 
culable harm is done, and women are again and again 
made parties to a traffic they abhor. True, some do not 
care ; but many do. To sell feathers of any kind as 
artificial is to obtain money by fraud. A man can no 
more be justified for selling as artificial that which is 
real, than for selling chalk and water as milk. 

To give an idea of the appalling waste of life which the 
trade in "Ospreys" is responsible for, we may remark 
that in London alone, last year, the produce of 196,000 
birds was sold ! As many were probably sold in the 
markets of Paris and Berlin, since London no longer has 
the monopoly of the feather trade. 




1 "g- .?•- Portion of a quill leather of a Rhea, i rorti the left side a large 
piece of the stem has been cut. liy twisting this round, the barbs 
become i.solated and simulate, crudely, the "osprev" plume. Such 
plumes are sold in the shops as "imitation ospreys," or as 
"vultures'" feathers. 



Unfortunately for the Egrets, these feathers are worn only 
during the breeding season, and by both se.xes. As a conse- 
(]uencethe slaughter of the adult birds at this time ensures 
the death by slow starvation of thousands of young. Really 
ihe prosecution of such butchery is devilish ; but what 
shall be said of those who, knowing this, yet purchase 
these ghastly trophies ? To write temperately on this 
aspect of the subject is difficult. The accounts published 
by Mr. W. E. U. Scott, an American ornithologist of 
the highest standing, are positively sickening. Yet he 
purposely refrained from making anything but the 
baldest statements of fact ; so much so, that those who 
do not know him, as the writer does, might accuse him 
of callousness. In his investigations, made in 1886, into 
the condition of some of the Bird Rookeries of the Gulf 
Coast of Florida, he found that since his last visit, si.x 
years previously, whole colonies of birds, numbering in 
their palmy days many thousands of individuals, had 
been absolutely wiped out by " plume-hunters." These 
ghouls travelled in bands of sometimes as many as 60 in 



a band. Let me quote two or three passages from his paper 
asasample. \'isiting thebreedingplaceof thereddish Egret 
in Charlotte Harbour, he writes : " This had evidently 
been only a short time before a large rookery. The trees 
were full of nests, some of which still contained eggs, and 
hundreds of broken eggs strewed the ground everywhere. 
. . I found a huge pile of dead, half-decayed birds 
lying on the ground, which had apparently been killed 
for a day or two. All of them had the ' plumes ' taken 
with a patch of skin from the back, and some had the 
wingscutoff. . . ." Again: ". . . theexlermina- 
tion of a Brown Pelican Rookery . . . is a very fair 
example of the atrocities that have been and are still 
being committed to obtain ' bird plumes.' . . . One 
afternoon, when Johnson (his informant) was absent 
from home, hunting, the old Frenchman (A. Lechevallier) 
came in with a boat and deliberately killed off the old 
birds as they were feeding their young, obtaining about 
one hundred and eighty of them. The young, about 
three weeks old, to the number of several hundred at 
least, and utterly unable to care for themselves in any 
way, were simply left to starve to death in their nests, or 
eaten by raccoons and buzzards." 

One feels sorely tempted to add to this catalogue of 
crime if only in the hope that it may stir up some com- 
punction in the minds of those directly concerned. 
Nowadays, unfortunately, we have become saturated 
with a spirit of scepticism, which is nowhere more in- 
jurious than in questions of this kind. " But is it not all 
horribly exaggerated ? It really can't be true, you know ! " 
is the cry of some to whom I have related these horrors. 
Others shrug the shoulders and say : "We really must 
not be sentimental ; let us set to work, quite dispassion- 
ately, and collect evidence." And there they leave the 
matter ! 

Statements have appeared from time to time to the 
effect that Egret farms, on the lines of Ostrich farms, have 
been started both in Tunis and in America. The Ameri- 
can farm was visited some time since, and found to con- 
sist of half-a-dozen birds in a small cage in a back yard. 
.\ detailed and glowing description was published in a 
German paper in 1896 of the success which had attended 
the establishment in Tunis. But the statement that the 
birds were fed on the carcases of horses, mules, and 
donkeys, aroused one's suspicions, and these are con- 
firmed by the assurance that the birds are deplumed 
i'u'icc a year. The long plumes, as a matter of fact, are 
worn only during the breeding season, and therefore the 
story of the double crop proves too much. After careful 
enquiry, I cannot find that there is a shadow of truth in 
any part of the story. But it has caused much mischief, 
since plumes have been sold as the product of such 
farms. 

Buyers of these feathers in milliners' shops are often 
told that the feathers are not plucked from the bird at 
all, but picked up off the ground. It is probably true 
that here and there a moulted feather is picked up in fair 
condition, but these can always be recognised by their 
soiled state and brittleness. They are useless for decora- 
tive purposes. Though normally white, these plumes, 
it should be remarked, are often dyed, but that does not 
make them " artificial." 

From the illustrations to this paper there can be little 
difficulty, really, in distmguishing the " Osprey " plume, 
taken from the Egret, from the imitation " Osprey " made 
of Rhea feathers, or from the feathers of the Peacock. 
Undoubtedly, and unfortunately, the Egret plumes are 
the more graceful. Were this not so, one might hope to 
persuade those w ho consider feather ornaments of this 
kind necessary, to adopt the wearing of Rhea feathers, if 



June, 1904 



KNOWLEDGE & SCIENTIFIC NEWS. Vs^l-d^-^) i 



31 



it can be shown that these birds can be farmed at a profit, 
as in the case of the Ostrich. So far, however, all en- 
deavours to start a new industry of this kind appear to 
have ended in failure. 

It is to be hoped that even imitation " Ospreys " will 
be eschewed in future, until some substitute for real 
feathers can be found which will possess the airy •,'race 
of the genuine " Osprey," or until they are made of 
feathers taken from birds bred for this purpose, or from 
some domesticated species. As it is, the good resolution 




Hig. 4. -An "imitation o>prey" as sold in milliner's .shop; said to be 
made of vultures feather's. It is really made by splitting and 
twisting feathers of the Rhea, or South American Ostrich. 

to wear only imitation "Ospreys" would create as much 
mischief as the wearing of the genuine plume, since the 
species called upon to furnish the " imitation " would 
themselves sooner or later suffer extermination. 

Finally, "Imitation Ospreys" are simply made by 
using the feathers of other birds, and up to the present 
time these have been of wild birds. The statements 
that imitation or artificial Ospreys are made of split 
quills, whalebone, or other material, are all absolutely 
false. 

Electric 
Wave MeaLSvirement. 



Dr. J. A. Fleming, F.R.S., exhibited at the Royal 
Society Soiree a very ingenious and interesting device 
for the measurement of electric wave lengths. The 
principle of the method will be grasped by anyone who 
has watched sea waves impinging against and rebound- 
ing from a sea wall. The returning waves sometimes 
reinforce and sometimes neutralise the oncoming ones, 
so that here we have a wave crest raised above its 
fellows, and there a wave neutralised or eliminated. If 
the waves were all quite regular, and were uniformly 
propelled and reflected, these points of reinforced and 
eliminated waves would be fixed. We should in short 
have "nodes" and "loops" of force in the train of 
waves. Dr. Fleming's apparatus for showing the nodes 
and loops of an electric train of waves consisted of a 



spiral of fine wire, along which the discharge of two 
Leyden jars propelled vibrations varying in number 
between a quarter of a million a second. The re- 
sultant electric wave travelled along the spiral at about 
fifteen hundred miles a second, was reflected and 
returned, thus establishing on the wire stationary electric 
waves, just as stationary aerial waves are produced in an 
organ pipe. The position of the nodes and loops was 
ascertained by use of a series of carbonic dioxide vacuum 



<rr. 




A, B.— Lonji coil of 5,000 turns of 

No. .((> wire. 
W. liurth wire. 
Li, Lj.— l-eyden Jars, each '0014 

mfd. capacil>. 
X. Variable Inductance Coil, o-2.;o 

microhenry's. 
I. Induction Coil — lo-inch spark. 
S. — Spark balls. 



lubes, which glowed when near a loop — the point where 
the oncoming and returning waves joined to produce a 
region of maximum electric force. Some further details 
of the apparatus are as follows : — 

The long solenoid of silk covered wire has 5000 turns 
and a total length of 643 metres. This solenoid has 
parallel to it an adjustable earth wire and a divided scale. 
The solenoid is connected to one point on an oscillatory 
electric circuit consisting of a couple of Leydens having 
a capacity of 0-00068 mid. and an adjustable inductance 
of o to 230 microhenrys and a silent discharger. When 
oscillations are set up in this circuit by induction coil 
discharges, and the fretjuency adjusted, stationary electric 
waves are set up in the solenoid. 

The position of the first node is always well defined. 
Theory indicates that the distance from the end of the 
solenoid to the first node should be to the distance 
between the first and second nodes in the ratio of 1:2-5, 
and that the distance between the first and second nodes 
should be half a wave length. Experiments with this 
apparatus give a mean value of i : 2-4 for the above ratio 
for the first five odd harmonics. 

The inductance of the long spiral is 100 microhenrys 
per centimetre of length and its capacity is 26 x 10"" of a 
microfarad per centimetre of length. From these data 
the velocity of the wave along the spiral is found to be 
about 196 million centimetres per second.'' From the 
wave lengths experimentally determined the correspond- 
ing frequencies are then found, and these agree substan- 
tially with the frequencies as calculated from the induct- 
ance and capacity of the Leyden jar circuit that is 
employed. Thus, corresponding to the first odd har- 
monic the node is 64 centimetres from the end. The in- 
ductance in the jar circuit is then 79 microhenrys, and 
the frequency as determined from the node -position and 
wave-velocity is 720,000 complete oscillations per second ; 
whilst from the jar circuit inductance and capacity it is 
690,000, or in fair agreement. The practical interest of 
the apparatus lies in the fact that it is in actual use for 
measuring the lengths of wireless electric waves such as 
are sent out from the station at Poldhu, in Cornwall. 

5 X I06 



4 /Capacity of Jar in 
» microfarads 



Frequency 

See Dr. Fleming's Cantor Lectures, 1900 



Induction of Coil 
in c.m.s. 



132 



KNOWLEDGE & SCIENTIFIC NEWS. 



[JlNE, 1904. 



The International 
Association of 
Academies. 



The chronicle of scientific movements of the past 
month would be incomplete without a record of the meet- 
ing in London of the General Assembly of the Inter- 
national Association of Academies, an event which 
brought together a singularly noteworthy gathering of 
men of science and of letters. .\n assemblage of such 
cosmopolitan and select character as this was, comprising 
the representatives of the premier academies of the world 
in the departments of knowledge, had not hitherto been 
seen in the metropolis. We have been privileged to 
receive and welcome from time to time the various foreign 
deputies to the peripatetic meetings of the British Associa- 
tion, as well as those attending the meetings of chemical, 
medical, and allied learned bodies, but never a congress 
of the world's academies. This necessarily stands on a 
plane distinct from composite gatherings held under 
auspices such as the above mentioned, responsible though 
they be in themselves, and worthy of all respect. 

The reason lies upon the surface, and is easy to state. 
An amalgamation of academies strikes a new note, for it 
is based on the wider authority that may be derived from 
international co-operation, regularly organised, and made 
applicable to the advancement of learning in its broadest 
aspects. Here is an effort to open up useful avenues of 
knowledge, and break untrodden ground under the stimu- 
lating influence of a common purpose. And what of the 
need for an organisation possessing these aims and 
characteristics ? The answer is that its inception is the 
actual and perceptible response to aspirations long enter-- 
tained by men of science and learning of various countries. 
It may be recalled that Sir Michael Foster, at the Dover 
meeting of the British Association in 1899, uttered these 
weighty words : — " Xo feature of scientific inquiry is more 
marked than the dependence of each step forward on other 
steps which have been made before. The man of science 
cannot sit by himself in his own cave weaving out results 
by his own efforts, unaided by others, heedless of what 
others have done and are doing. He is but a bit of a great 
system, a joint in a great machine, and he can only work 
aright when he is in touch with his fellow-workers." 

From general considerations of this nature, reference 
may pass to the initial steps that led ultimately to 
the foundation of what is now denominated the Associa- 
tion of Academies. Germany, the home of the greatest 
of all academicians, Leibnitz, had zealously fostered for 
many years a union of the Eoyal Societies of Gottingen 
and Leipsic, in collaboration with the academies of 
\ienna and Munich, called a " cartell." This met 
annually, turn by turn, at convenient centres for the 
purpose of discussing matters of science and learning 
in which a partnership of effort was beneficial for the 
several ends in view. It so happened that the scheme 
of the Royal Society of London (now in active operation) 
for the promotion of a universal and continued catalogue 
of scientific literature on an international basis was one 
of the subjects submitted to the cartell at its meeting at 
Gottingen in the year 1S99, at which, it should be 
mentioned, English representatives were present by 
special invitation. The latter, however, at the time, 
had been coupled with the expression of a wish that the 
Royal Society would consider the question of itself join- 
ing the cartell. To this cordial and significant desire 
for an extension of the boundaries of the cartell's sphere 



of work — it could mean nothing else — the delegates were 
empowered to say that the Society was disposed to join 
if the principle of a plan for the founding of an inter- 
national combination of the more important societies 
and academies of the world was conceded, and, in fact, 
made the objective. The little set of foreign academies 
agreed, and the next move forward lay in the calling of 
a conference at Wiesbaden in the same year, to consider 
the general agreement previously arrived at, and to 
discuss the lines of establishment of the amalgamation 
thus forecasted. Here it is not out of place to recall that 
the English delegates on this occasion were Sir .\rthur 
Eucker, Professor A. Schuster, and Professor H. E. 
Armstrong. 

It is beyond the limit of our space to fully detail the 
subsequent and steadily progressive history of the move- 
ment for an international alliance. Statutes and laws 
were, however, formulated, and one by one the adhesion 
of the greater societies and academies of the world was 
obtained. The appointment of an international council 
was ratified, whose duty it should be to conduct the 
business of the .Association in the intervals of the tri- 
ennial meetings of a plenary General Assembly, such as 
that which has just concluded its deliberations. Further, 
the decision was taken that the first gathering of the 
latter body should be held in Paris in 1901 — an event 
which virtually marked the birth of the International 
Association. To M. Gaston Darboux, the distinguished 
Permanent Secretary and doyoi of the Academy of 
Sciences of Paris, fell the privilege of acting as Presi- 
dent. By a unanimous vote London was then chosen as 
the venue of the next Assembly. 

The delegates who have attended the Congress repre- 
sented the full complement of constituent academical bodies, 
and were drawn from the cities of Amsterdam, Berlin, 
Brussels, Budapest, Christiania, Copenhagen, Gottingen, 
Leipsic, London, Madrid, ^Munich, Paris, Rome, St. 
Petersburg, Stockholm, \'ienna, and Washington. In 
the case of London, the Royal Society delegation was 
composed of eighteen Fellows, including Sir William 
Huggins, its venerable President ; while the British 
.Acadrmy, which is now, of course, within the pale of the 
Association, was represented by Lord Reay, the Presi- 
dent, and six other Academicians. Among notable 
foreign men of science and of letters present were the 
Count de Franqueville, M. Moissan, Sefior Jose Eche- 
garay. President of the Royal Academy of Sciences of 
Madrid, Dr. Viktor von Lang, of \ienna. Count Balzani, 
and Prof. Svante Arrhenius, the eminent Swedish 
chemist. 

Among the subjects that have been under consideration 
during the Congress may be mentioned a scheme 
for carrying on magnetic observations at sea, with the 
view of establishing a comprehensive magnetic survey 
around a parallel of latitude— a project requiring inter- 
national co-operation to be completely successful. Seis- 
mological and geodetic investigations were under discus- 
sion—domains of inquiry in which scientific men of 
various nationalities are just now much interested. The 
British Academy promote a scheme for a lexicon of the 
Greek language; the Academies of Copenhagen and 
Berlin put forward a plan for a Corpus Medicorum .Vnti- 
quorum. Then the important question of the establish- 
ment of an institute for the purpose of investigating the 
anatomy of the brain was under reference — a subject on 
which great unanimity prevails among foreign and 
English men of science. The above are instanced merely 
to indicate a few of the matters of scientific and literary 
interest that are before the Association in some stage 
or other. 



June, 1904 ] 



KNOWLEDGE & SCIENTIFIC NEWS. 



133 



The labours of the plenary Assembly were lif^htened 
during the period of meeting by a series of hospitalities 
planned by the Royal Society, the Lord Mayor, the 
University of London, and a number of representative 
men of science ; those carried out by the last-named 
being of a particularly cordial and pleasant nature. In 
addition, the I'niversities of Oxford and Cambridge 
arranged visits, and the conferment of degrees upon cer- 
tain of the foreign delegates took place. 

REVIEWS OF BOOKS. 



Aeronautics. — " My Airships," by A. Santos Dnnioiil (Grant 
Richards ; 0/- net), is not a student's book. It is a popular work, 
and it does not, even when judj;od by this modest standartl, artord 
very much more information than the diiiijent newspaper reader 
might have gleaned from thi: files of tlu; daily papers. It is 
prolific in anecdotes of M.Santos Dumont's adolesccnce.and it 
is charmingly illustrated by photographs of all his tlying 
machines and most of his accidents. These photographs arc 
indeed the most valuable feature of the volume, and furnish 
an idea of tlie evolution of the navigable form of airship, 
or balloon. M. Santos Dumont does not furnish any positive 
data as to the exact speeds at which he has been al>le 
to drive his sliips; but he assumes tliat they travelled at a 
higher rate than that which Sir Hiram Maxim, for ex.imple, 
thinks that an airship of the balloon type can be driven. 
" When, therefore, I state that, according to my best judgment, 
the average of my speed through the air in those llighls (llights 
with No. 6 in uj02| was between 30 and 35 kilometres (18 and 
22 miles) per hour, it will be imderstood that it refers to speed 
through the air whether the air be still or moving, and to speed 
retarded by the dragging of the guide rope. Putting this ad- 
verse influence at the moderate figure of 7 kilometres (4;' miles) 
per hour, my speed through the still or moving air would be 
between 37 and 42 kilometres (22 and 27 miles an hour)." If 
this can be taken .as trustworthy then tliere seems to be 
not the slightest reason why M. Santos Duniont should not 
" lift " the Grand Prize of S 100,000 which the St. Louis Exposi- 
tion is offering for the best average times made over a fifteen- 
miles triangular course, provided that the average speed is 
not less than i8| miles an hour. Two points are specially to 
be noted about M. Santos Dumont's method and the possibilities 
he claims for it. One is that he is never foolhardy, and keeps as 
close to the ground as he can, since nothing is to be gained by 
height. The other is Ih.at he maintains that the chief difficulty 
in driving against the wind is not the " push " against the front 
of the balloon ship, but the suction or pull at its stern. The 
defect of the compilation is chiefly one of omission. One 
might well imagine after reading "My Airships" that M. 
Santos Dumont alone had done anything worth recording 
in the sphere of balloon propulsion, A few allusions are made 
to M. Giftard's unproductive experiments of fifty years ago, 
but the verj' successful achievements of MM. Reuardand Krebs, 
who practically accomplished almcst as much as M. Santos 
Dumont has done, are merely referred to as " the trials of 
such balloons . . in 1883 had been repeated by two con- 
structors in the following year, but had been finally given up in 
1885," And yet he says: " Before my experiments succeeded, 
were they not called impossible ? " Moreover, no allusions 
whatever seem to be made to the Lebaudy balloon, which, 
according to all accounts, has surpassed the author's machines 
in speed, in distance travelled, and in the number of successful 
return trips. 

Geology. — Messrs. Blackie and Son have published a fifth 
edition, revised, of Mr. Jerome Harrison's "Text-Book ot 
Geology." It is an admirably compact text-book in its present 
form ; the new photographs arc as welcome as they were 
necessary ; and the addition of a table showing the range in 
time of invertebrate fossils is extremely and distinctively 
useful. 

Builders' Quantities — Mr. H. C. Grubb has written " Builders' 
Quantities" (Methuen and Co.) with the intention of giving 
sufficient and necessary information to technological students 
for the City aud Guilds examination on the subject, and to 



candidates for the Board of Education examination on Build- 
ing Construction. The book is eurincutly practical, and is not 
without acute interest for those whose dealings with builders 
consist solely in paying their bills. 

Radium. " Radimu, and .Ml .M>i>ut It " (Whittakcr aud Co.), 
by S. R. Boltone, is a cheap handbook which does not justify 
its subsidiary title. It is, none the less, a h.indy suunnary of 
the more popularly interesting facts about radium, and it adds 
a rather hasty suunnary of some of the theorii-s concerning 
radium activities, ending with the doubts cast by Sir W, 
liuggins' examination of the spectrum of radium on its final 
degradation into helium. 

Entropy. Mr. James Swinburne repeats in "luitropy" 
(('unstable) those views on thermodynamics which he has 
been repeating with consider.ible satislaetiou (o himself both 
before and since he read his disturbing paper on the " Re- 
versibilily of Thi'rmodynamics " to the Physical Section of the 
British .Association last year. Since its publication it has 
been denounced by tlie chief opponent of Mr. Swinburne's 
views as liki-ly to be extremely disturbing to earnest engineer- 
ing students ; but it has at any rate been productive of some 
interesting and spirited rejoinders from Professor Perry. As 
.in example of Mr. Swinburne's lively style, we may quote the 
following passage : "The unit of heat, which is quite an uu- 
necess.ary nuisance, has no name, for British thermal unit is 
not a name; it is an opprobrious epithet." 

"Metal Working," by J. C. Pearson (Jolni Murray; 2s.), is an 
admirable guide to the practical manipulation of tools for the 
working of metals. Tlie sulijects treated of are divided under 
the various headings, such as " l'"iling," " Scraping," " Solder- 
ing," " Riveting," iS:c., and each operation is not only clearly 
described, but good outline figures and numerous jihotogr.iphs 
add greatly to the value of the deseriptioiis, so that any one 
mastering this little work may consider himself a fairly expert 
metal worker. 

BOOK NOTICES. 



I Flowering I'lants and Perns. A second edition of the " Manual 
and Diction.iry of the Moweriiig Plants and Eerns " (("am- 
bridge University Press ; 10s. Od.), wliieh Mr. J. C. Willis origin- 
ally wrote in two volumes, has now been pulilished in a single 
volume to its great advantage in accessibility of information 
.and general usefulness. Mr. Willis's work, modest in aim, 
and described by its author as a mere coir.pilation, is of en- 
cyclopjedic value to the student of botany. As in the first 
edition, its staple contents are a dictionary in which the whole 
of the families and the important genera of flowering plants 
are dealt with ; and this general information is supplemented 
by special treatment in Part I. of the morphology, natural 
history classification, geographical disposition, and economic 
uses of the flowering plants and ferns. To the new edition 
has been added a mass of additional material; and new 
features are the articles on outfit, on collecting and preserving 
material, on observing and recording, and on general field 
work — a method of botanising which receives too little .itteii- 
tion. We cannot pay the wi)rk a higher compliment than that 
of saying that Mr. Willis's expressed aim " to render the work 
sufficiently complete forthe requirementsof botanical students, 
schoolmasters, travellers, residents in outlying districts, and 
the considerable class of ])eople who have an indirect interest 
in botany, and need some general work of reference on that 
subject . . ." has been completely and triumphantly at- 
tained. At the same time the student at home will l)e able to 
make constant use of it as a treatise of reference in general 
morphology and geology on plant distribution and systematic 
botany. 

War in tiie Far East, - W'e have received from Messrs, Virtue 
and Co. for review the first volume of a history of the Russo- 
Japanese War, "War in the P"ar East," by E. Sliarpe (Irew. 
Vol. 1, which is attractively bound and illustrated, deals with 
the preliminary history which led to the outbreak of war. The 
evolution of Modern Japan is traced ; the relations of Japan 
with Korea and China are described, .and an account is given 
of the Chino-Japanese War. It is shown how the interven- 
tion of luiropean Powers in the settlement of Peace negotia- 
tions and the sub.sequent Russian encroachments led inevitably 
to the present crisis in the P'ar East. 



134 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 




Conducted by F. Shillington Scales, f.r.m.s. 



MITES. 



Cecil Warburton, M.A. 



(Coniinucd from page 105.) 
Akp now, perhaps, a somewhat more detailed account 
of the animals we are looking for may not be out of place. 
That they are not insects, but arachnids, is doubtless 
perfectly well known to readers of " Kxowledge." They 
are without antenns, and have normally eight legs when 
mature. The_ Oribatida are blind, but when eyes do 
occur in the mite tribe they are simple and not compound. 
The Arachnida of this country are represented by the 
spiders, the harvestmen, the " false-scorpions," and the 
mites. The false-scorpions, or Chelifers, are unmistak- 
able, and the spiders are distinguishable at a glance from 
the mites because of the narrow pedicle or "waist " which 
joins the two portions of their body. The characters 
which separate the mites from the harvestmen are not 
quite so obvious, but the latter have the abdomen more 
or less distinctly segmented, and have always two eyes 
on a turret in the middle of the fore-part of the body. In 
practice there is little danger of confusing the two groups, 
as very few mites, except the easily recognised ticks, are 
equal in size to the smallest British Phalangids or har- 
vestmen. All mites live on fluid nutriment, some deriv- 
ing it from animals, others from plants, and their mouth 
parts are accordingly adapted for piercing and sucking. 
It will be useful, perhaps, to give in this place a short 
review of the principal acarine groups, and to indicate in 
a few words the general condition of our knowledge with 
regard to them. 

First of all, then, we have two families of very minute 
worm-like mites, the Eriophyidre (or Phytoptida-) and 
the r)emodicida\ The former are generally known as 
gall-mites, and are responsible for various plant diseases, 
a familiar example being the disease of " big bud " in 
black currants, which is caused by Eriophyes rihis. The 
Demodicidae are animal parasites, and the best-known 
example is Demode.x foUiciiloriim, parasitic in the hair 
follicles of man. Then follow the Sarcoptidre, or itch- 
mites, extremely unattractive creatures, which are external 
parasites of various vertebrate animals. All the above, 
possessing a certain economic importance, have neces- 
sarily attracted more or less attention from those who 
study the diseases of animals and vegetables, but from the 
faunistic point of view there is much ignorance with re- 
gard to them in this country. For further information 
we may refer the reader to Neumann's " Parasites of 
Domesticated Animals," which has been translated by 
Dr. Fleming, and to Connold's handsome volume on 
" British \'egetable Galls." 

We next come to the Cheese-mite tribe or Tyrogly- 
phids, which feed chiefly on decaying animal or vegetable 
matter. They are a small group of soft-bodied mites, 
generally white in colour, and the British species have 
recently been monographed by Michael in the publica- 
cations of the Ray Society. Then follow the Oribatids, 
with which we are pnncipally concerned in the present 



paper, and they are succeeded by the ticks or Ixodidae. 
Though their comparatively large size has probably made 
the ticks the most familiar examples of mites to the 
uninitiated, yet we are only beginning to know some- 
thing ^.bout them, and recent investigations in their 
direction are again entirely due to their economic impor- 
tance as the medium by which various dread diseases are 
communicated to man and domestic animals — chiefly in 
foreign countries. Neumann's " Parasites " may again 
be consulted, and the same author has written a Revision 
of the Ixodida;, but the British ticks are only very 
slightly known. 

The same may be said of the Gamasida?, free-living 
predaceous mites, examples of which are sure to be found 
among the moss in which we are seeking the beetle 
mites. They run rather quickly and use their long front 
legs chiefly as feelers. A serious attempt to deal with 
the British species is very much to be desired. 

Other families of free-living mites, also clamouring for 
attention, are the Bdlellida? or snouted-mites, and the 
Hydrachnida' or fresh-water mites, and then we come 
to the Trombidiida?, which include the velvety scarlet 
" harvest mites," and the Tetranychidre or spinning 
mites, a familiar example of which is the " red spider," 
so obnoxious to fruit growers. Almost the only English 
work which professes to deal with these groups is Murray's 
British Museum hand-book entitled " Economic Insects 
— Aptera," a book necessarily long out of date, and not 
free from grave errors. It is abundantly clear, therefore, 
that much remains to be learnt with regard to the British 
Acari, some families of which are practically untouched 
by any recent investigator. 

And now for a few final words concerning the Oriba- 
tida8, which afford in many respects the best introduction 
to the study of the mite tribe. Four stages are distin- 
guishable in the life-history of these mites — egg, larva, 
nymph, and imago. In some species the transformation 
or metamorphosis is very complete, there being hardly 
any resemblance between the nymph and the imago, 
while in others the change is not so striking. The eggs 
are relatively very large, and the larva; which hatch out 
may be recognised as such by the fact that they possess 
only six legs. The fully-grown creatures are generally 
slow moving, and with hard or leathery integuments. 
Their body is usually pretty clearly marked off into two 
regions, the cephalothorax and abdomen, though only in 
one genus, Hoploderma, are these capable of independent 
movement. Whether a mite is an oribadid or not may 
be readily determined by examining the cephalothorax, 
for in this family there is always present a pair of curious 
sense organs known as pseiidosiigniatic ovf^atis. They are 
modified hairs, of varying shape, proceeding from the 
centre of two circular pits with raised edges situated near 
the sides of the hind part of the fore-body, near the com- 
mencement of the abdomen. Their peculiar shape and 
disposition are of prime importance in determining the 
species of one of these creatures. In the nymplis the 
legs always terminate in a single claw, but the images 
may be either monodactyle or tridactyle. The nymphs 
moult three times before the mature stage is reached, but 
in some cases the cast skins are never entirely thrown off, 
and the adult mite walks along with the three nymphal 
skins still adhering to its back. 

These mites differ very much in the general appear- 
ance they present, some being smooth, glossy, and beetle- 
like, while others have a rugged, leathery appearance 
and are furnished with warty prominences, or bristle with 
hairs and spines. Some of the more hairy species have 
a remarkable habit which is a distinct nuisance to the 
collector. They cover themselves — doubtless for pro- 



June, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



135 



tective reasons — with particles of dirt, which entirely 
alter their appearance, and are by no means easy to 
remove completely, and these grotesque moving particles 
of dust and lUbris have to undergo very rigorous ablutions 
before they are ready for the cabinet. 

Roya-l Microscopical Society. 

April 20. — Dr. Hy. Woodward, F.K.S., Vice-President, in 
the chair. A large tank microscope, ni.ide by Thomas Ross, 
presented to the Society by the Committee of the Qiiekctt 
Microscopical Club, was exhibited. It was made not later 
than the year 1S70, and was dcsisiied for the purpose of 
examining objects contained in aquaria. It was a beautifully 
made and highly-finished instrument, having nearly every 
conceivable adjustment. The annual exhibition of Pond-Life 
was given this evening by Fellows of the Society, assisted by 
members of the Onekctt Microscopical Club. 

Quekett Microscopical Club. 

The 4ijth ordiu.ary meeting of the Club was held on 
April 15, at 20. Hanover Square, W. — the President, Dr. K. J. 
Spitta, V.P.R..-\.S., in the chair. A paper was read by Mr. W. 
Wesehe, F.K.M.S., " On some new Sense-organs in the Diptera." 
The paper was well illustrated by diagrams and drawings. 
After briefly reviewing the investigations of Packard, Flatten, 
Forel, Lubbock, and others into the senses of taste, smell, and 
hearing in insects, the author proceeded to show that he had 
found processes homologous with the " taste-hairs " of Krae- 
peUn in some Orthoptcra, Coleoptera, Diptera. and Hymenop- 
tera. Organs were then figined on the antenna; of Gastro- 
philusctjui, L., Stratiomys chamckoii . L., and Bihio hoiinlnniis. L., 
which were thought to be typical olfactory organs. Both the 
antenn<E and palpi of insects were considered capable of re- 
ceiving the stimulus of several senses, but their capacities 
differed so much in various genera and species that a general 
rule could not be formulated. The author had found new sense 
organs on the femora of maTiy Diptera which he was unable to 
assign to any sense of which we have conception. Other 
organs of quite different construction had been found on the 
libias of some minute Fmpid;e. Their functions were quite 
unknown, and several experiments which had been made with 
a ^ew of discovering the functions had yielded only negative 
results. 



Journal of the Quekett Club. 

The April number of this Journal, wliich has just reached 
me, contains sever.al useful articles and notes, amongst which 
are a note by Mr. F. J. Cheshire concerning Abbe's test for 
aplanatism, and a simple apertometer derived therefrom, the 
apertometer being figured on a separate plate, so that it can be 
cut out and used on the microscope in the way described by 
the author. Mr. F. P. Smith, the new Editor of the Journal, 
contributes a note on the spiders of the subfamily Erigoninse; 
Mr. Rheinberg a note on an overlooked point concerning the 
resolving power of the microscope ; and Mr. Scourfield con- 
cludes his synopsis of the British fresh-water Entomostraca, 
including the Ostracoda, Phyllopoda, and Brancliiura. 

Microscopic Slides. 

In the advertisement columns of this magazine will be 
found a notice relating to the sale of duplicates of slides from 
the collection of Mr. J. Hornell, of Jersey. Many of my 
readers will be familiar with these beautiful preparations, 
which include botanical as well as zoological subjects, and as 
they are now being dispersed, and are offered at quite nominal 
prices, I have felt myself justified in calling attention to 
them. 



Practical Botany and Geology Classes. 

I have been much interested in receiving from Mr. J. M. li- 
Taylor, Curator of the Free Museum at Paisley, particulars of 
field rambles held in that neighbourhood from .'\pril till the 
close of the public schools in July, with a view to giving 
students a practical acquaintance with nature. The plan is 
excellent, and well worth being taken up by other of our many 
Free Libraries. Excursions are held twice 1 week, namely 



on Wednesdays and Fridays, leaving Paisley at 5.40 p.m., or 
such other time as may be agreed upon, many of the excur- 
sions being in brakes so as to get well into the surrounding 
country. For the last five or six years during each session the 
class has brought in from its field rambles the typical wild 
plants, grasses, ferns, &c., of the time and district, and these 
have been placed on view in the Free Museum with their 
English ancl scientific names attached. Fresh specimens of 
plants were added twice weekly, and lists thereof published in 
one of the local daily papers. Nature knowledge was studied 
practically at these excursions with the help of the camera, a 
portable microscope, and a dredge for streams and ponds. At 
the New Year a four days' exhibition was also held. By the 
kindness of a local lady, Mrs. Poison, of Lcven Castle, prizes 
of microscopes were offered to the members of the class for 
the best collection of dried, mounted, and named wild plants, 
grasses, and ferns ; aiul a microscope was likewise offered to 
working men and women who would also make a dried collec- 
tion, with names (which were obtained from specimens shown 
in the Museum), but who were not members of any class or 
Natural History Society, where names of plants were given. 
This prize was gained by an ex-mason. For members of the 
class each collection had to contain 400 specimens; and for 
the collection made by working men and women there must 
be 200 specimens. It is to be hoped that so excellent a scheme 
mav find manv imitators. 



Notes and Qvieries. 

Chrysanthemum Fungu8. (C.H.C.) 

I have submitted the chrysanthemum leaves to Miss 
E. M. Gibson, who has for some time been investigating this 
fungus in tlie Cambridge i;niv('rsity Botanical Laboratories. 
I learn from her that it is quite a new species, having only 
been discovered some six or seven years ago, and has been 
described, as far as present knowledge allows, by Dr. Ernst 
Jacky, in the Zcitschrift f. Pflaur.cii-Krankhcitin, Vol. X. (ujoo). 
It has been tentatively named " Uredo-chrysanthemi," but 
though Mr. Massee, in the Gardener' a Chronicle speaks of other 
stages teleuto or aecidio spores have not hitherto been 
definitely found, or at least the evidence is not complete. 
Miss Gibson says she has herself quite failed to find any other 
stage than the nrcdo spores, as on the leaf you sent me. 
Apparently the fungus, though unquestionably injurious, is not 
necessarily destructive to the plants, but various species living 
under similar conditions, show a curious variation in suscepti- 
bility to attack, especially under high cultivation. .So far the 
conditions favourable or otherwise to the fungus have also 
not been determined. 

Making Rock Sections. 

Mr. C. H. Caffyn, of Hornsey, writes with regard to rock 
sections: " I tried to make sections, as recommended in the 
text-books, with emery powder on a piece of zinc or glass, but 
it was a very long jol), and the results wore not altogether satis- 
factory, and were quite out of proportion to the time employed. 
I then thought it could perhaps be done with ordinary emery 
cloth, and I find this does very well, and takes much less time. 
I first chip off .as thin a flake as possible, and grind one side 
flat on ' F ' emery cloth. Then I use No. i and then No. o, 
and then polish on a piece of No. o that has been rubbed 
down with a bit of itself to take the surface off. The piece of 
rock is then stuck on a bit of plate glass with ordinary mucil- 
age—I use Stephen's gum. When dry, the rock can be rubbed 
down as mentioned above. Great care must be taken when 
rubbing on the No. o to finish, as the section is apt to crumble 
at the edges. When it is thin enough (which I generally judge 
by reading print through it), put the piece of glass and section 
in ordinary water till the section floats off the glass. Then 
wash with a sable brush to remove all gum. Soak in methy- 
lated spirit to remove water. Evaporate spirit, soak in ben- 
zene, and mount in balsam and benzole." Mr. Caffyn has 
sent me some slides to look at which have been made in this 
way, and which seem quite equal to those made by the 
ordinary process. 

[Communicationi and ciKiuiyies on Microuopical mailers are invileU, 
ami should he addressed la F. SliillhigUm Scales, ■■ Jersey," SI. 
Barnabas Road, Cambridge. \ 



136 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



The Face of the Sky for 
June. 



By \V. Shackleton, F.R.A.S. 



The Sun. — On the ist the Sun rises at 3.51, and sets 
at 8.5 ; on the 30th he rises at 348, and sets at 8.18. 

The sun enters the sign of Cancer on the 21st at 9 p.m., 
when summer commences. 

The equation of time is negligible on the 14th. 

Sunspots have been very conspicuous of late, whilst in 
addition spectroscopic observations of the Sun's hmb have 
shown many fine prominences. 

The positions of the spots with respect to the equator 
and a.\is may be derived from the following table : — 



On the 1st Saturn rises about midnight, and on the 
30th about 10.15 P-™- The northern surface of the ring 
plane is presented to us. 

Uranus is in opposition on the 19th, hence about this 
date he is on the meridian at midnight. The apparent 
diameter of the planet is 4". In consequence of his low 
altitude, it is rather difficult to see the planet with the 
naked eye, but any slight optical aid renders him easily 
visible. The appended chart shows his position in 
Sagittarius. 



Date. 


Axis inclined to W. from 
N point. 


Centre of disc, N of 
Sun's equator. 


June 5 .. 
.. 15 ■■ 
.. 25 .. 


13° 54' 
9''45' 

5= 21' 


0° 3' 
1° 15' 
2° 25' 



The Moon :- 



Date. 


Phases. 


H. M. 


June 6 . . 

., 13 •■ 

20 . . 

,. 27 .. 


([ Last Quarter 
• New Moon 
5 First Quarter 
Full Moon 


5 53 a.m. 
9 II p.m. 
3 II p.m. 
S 25 p.m. 




Occulta-tions. 

The particulars of the only occultation likely to be 
observed during the month are as follows : — 



Date. 



Star's Name. 



June 24 



Magni- 
tude. 



Disappear- 
ance. 



Reappear- 
ance. 



d Librae 



43 I 11.55 pm. 10 30 a.m. (25th) 



The Planets. — Mercury is a morning star in Taurus, 
he is at greatest westlerly elongation on the 8th, when 
he rises about an hour in advance of the sun. 

Venus is a morning star, but too near the Sun for 
observation. 

Mars is in conjunction with \'enus on the 19th, and 
therefore also out of range. 

Ceres. — The minor planet Ceres is in opposition on 
the 5th, when the magnitude is 7-4. On this date the 
asteroid has the same declination as the star 4 Ophiuchi 
but is oh 1 8m 41s west of the star. 

Jupiter is a morning star, rising about i a.m. near the 
middle of the month. 

Saturn is in the eastern portion of Capricornus near 
the star 3 ; the planet is at the stationary point on the 
1st, after which date his motion is retrograde. 




Path ok Uranu.s in Sagittarius : — 

Neptune is in conjunction with the Sun on the 27th, 
and consequently is unobservable. 

Comet a 1904. About the middle of April the first 
comet of the year was discovered in Hercules by Brooks, 
at Geneva, N.Y., U.S.A. It is a faint telescopic object, 
diminishing in brightness, and is slowly moving along 
the borders of Draco into Ursa Major. Early in June, 
it should be near the star i Ursae Majoris. 

The Stars : — 

Positions of the stars about lo p.m. : — 
Great Bear, Cor Caroli. 
Ursa Minor, Cepheus, Cassiopeia. 
Lyra, .Vquila, Saggittarius, Cygnus. 
Hercules, Ophiuchus, Corona, Libra, 



Zenith 
North 
East 
South 

Scorpio. 
West 

~N.\V. 



-S.W. : \'irgo and Bootes. 



Quadruple star. 
The star can be 
(mags. 4-6, 4-5: 



Leo, Cancer.- 
: Capelhi. 

Telescopic Objects: — 

Double Stars: — ,3 Scorpii, XM-i^o™, S. 19' ^i', mags. 
2-0, 4-0; separation i3"-i. 

( Lyra-, XVIII." 41'", N.39'^ 32'. 
better known as the " double-double.' 
divided into two components «' and 
separation 207") with the slightest optical aid and under 
favourable conditions the naked eye alone is able to 
effect separation; using a power of about 150 on a 3 or 
4-inch telescope, each of these can again be divided, t^ 
mags. 47, 6-3 ; separation 3"-o; f'^ 4-9, 5-2, 2"-^. 

f Lyrre, XVHI." 41'", N. 37° 30', mags. 4-3, 5-9; 
separation 44". \'ery easy double ; power 20. 

i Lyra', .XVni.''5i'", N. 36" 49 ', mags. 5-5, 5-9; naked 
eye double. Glorious field for low powers (I Ff 66). 

S Serpentis, XX'III.'" 51'", N. 4^ 4', mags. 3-9, 4-2; 
separation 22". Fine pair in small telescopes. 

Clusters and Nebula-. — M80 (Scorpio). A compact 
globular cluster half way between a and 3 Scorpii ; looks 
like a nebula in small telescopes. 

M57 (Ring Nebula in Lyra). Easily found by setting 
the telescope J of the distance from jS towards y. Rather 
faint object, but readily seen as a small ring in a 3-inch ; 
it is the only annular nebula visible in small telescopes. 



KDomledge & SeieDdf le Nettis 

A MONTHLY JOURNAL OF SCIENCE. 

Conducted by MAJOR B. BADEN-POWELL and E. S. GREW, M.A. 



Vol. I. No. 6. 



[new series.] 



JULY, 1904. 



r Entered at "1 
I Stationers' Hall. J 



SIXPENCE. 



j Contents and Notices. See Page VII. 

Flower Mimics acnd 
Allviring Resemblance. 

By Percy Collins. 



Not the least curious insects which gain protection from 
their enemies by means of a likeness to surrounding 
objects are those which may be described as flower 
mimics. Of these, some remarkable instances have 
already been described, nor is it unlikely that others, 
equally striking, remain to be discovered. Among 
butterflies, one may often trace a likeness between the 
resting insect and the buds or blooms amongst which it 
has settled. This flower resemblance is seen in the case 
of our common "white" butterflies, which, when settled 
among such blossoms as those of the pea tribe, have an 



"C 




n'liiMgf -m^ 


A 













Group of Orange-tip Butterflies and Cow Parsley. 

undeniable general likeness to the unopened flowers. 
Again, a contributor to the Speaker recently pointed out 
the resemblance of the resting " wood white " butterfly 
{Leucophasia sinapis) to the flower buds of the corn 
wheat — a plant invariably abundant in the woods fre- 
quented by this dainty insect. The present writer is 



able to substantiate this ohservalion, being familiar with 
one of the few remaining dij;tricts wherein the " wood 
white " is still fairly common. 

A more specialised case of tloral simulation is seen in 
the " orange-tip " butterfly {Eiuhloc mi'dinniiii-s), aninscct 
familiar to all lovers of the outdoor world, 'i'he upper 
surface of this butterfly's wings are white marked with 




A Species of Fl^ilit from Perak. (Somewhat enlarged.) 

black, with (in the male only) two large orange areas in 
the fore wings. The colouring of the underside, which 
is identical in both se.xes, seems designed in imitation of 
a small truss of the tiny white florets of some umbellifer- 
ous plant, such as the hedge parsley. Such pale or 
white flower masses are among the commonest blossoms 
of the hedgerow in the springtime, when the "orange-tip " 
butterflies are on the wing. It is, of course, extremely 
doubtful whether the butterflies have any knowledge of 
their protective colouring ; nor is there any ground for 
supposing that the insects select the neighbourhood of 
umbelliferous blooms as resting places. At the same 
time, it seems quite admissible to suppose that the colour 
likeness of E. aiyduiiniies to florescence common in spots 
frequented by the insect is likely to stand it in good stead 
as a protective disguise. The underside of the hind 
wings, between which the fore wings are folded when 
the insect is at rest, are mottled white and green — the 
white patches resembling tiny florets, while the green 
represents the background of vegetation against which 
they are supposed to be seen. Those who have not ob- 
served the " orange tip " butterfly in nature may judge 
of the closeness of the protective resemblance by a glance 
at the accompanying photograph. 

Several of our common " blue " butterflies have wings 
mottled and spotted on the under surfaces in a manner 
which suggests the plantain heads and grass flowers 
amon'r which these insects are accustomed to rest. And 



138 



KNOWLEDGE & SCIENTIFIC NEWS. 



[July, 1904. 



as these butterflies are accustomed to go to roost long 
before twilight has settled in, it is quite likely that their 
shape and colouring protect them from the attacks of 
birds. 

Perhaps the most curious case of protective flower 
resemblance is that vouched for by Professor Ciregory, 




Individuals of a Species of I'Uila grouped upon a Plant Stem. Note 
flower-like appearance. 



and described in his work, " The Great Rift \'alley." 
The insect in question is a species of Flata, which is a 
genus allied to the scale-msects, and to the Apliida. 
The species described by Professor Gregory is indigenous 
to British East .Africa, and is dimorphic — a certain 
number of indixiduals of each sex being bright pink in 



colour, while others are bright green. These insects 
resemble the green fly, or Aphida, in habits, sitting 
motionless on plant stems for long periods and feeding 
upon the sap. The manner in which the individuals of 
the present species are said to group themselves is very 





W'j^w^Sk 'j2K 


MhBJ^^ 


^^^^ ' ^^fll^Htd!^^BI& 






^f 


-,m i 




;_^i,^ 




A green Mantid, from Ceylon, lying in wait among foliage. 



Brown Mantid. from Usambava, at rest on bark. 



remarkable. The pink ones sit upon the lower part of 
the stem, while the green ones have their place above, 
towards the extremity. Further, the developing larvae, 
which secrete long filaments of a waxy substance, and 
are quaint, fluffy little objects, sit beneath the pink indi- 
viduals at the lowest part of the stem. Thus, the exact 
appearance of a spiked inflorescence is simulated. 
The fluffy larvre have a distinct likeness to seed 
poJs. Tiie pink individuals might be mistaken 
for drooping flowers, while the green ones, higher 
up the stem, look like so many undeveloped 
buds. Professor Poulton, however, has re- 
marked that the grouping of green and pink 
insects in Professor Gregory's observation was 
probably accidental. 

So far, we ha\ e examined only instances of 
protective resemblance — instances, that is to 
say, in which the colours, or the colours and 
form, of an insect are seen to be of value to it as 
a means of escaping detection. W'e have now 
to consider cases in which the appearances of 
insects, while possibly screening them from 
the attacks of their enemies, have the additional 
advantage of enabling them to approach un- 
observed the creatures upon which they them- 
selves prey. Such instances of resemblance 
may be termed aggressive. 

The curious "praying insects," or Mantidie, 
afford many striking examples of aggressive 
resemblance. The whole of this large family 
is insectivorous in habit, and the majority of 



Jl'LV, 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



^W 



the species are either green or brown in colour. So that 
when sitting motionless among foliage, or upon the bark 
of trees, they are not only inconspicuous to such 
enemies as birds and lizards, but are also hidden from 
the small insects which form, in the main, their food. 
The MantidcE are almost all sluggish in their move- 




Another view of same insect. 

ments, seeming to be aware that the needs of their life 
will be best served by tranquillity, rather than by effort. 
They sit motionless in the sunshine — brown species upon 
bark, green species amongst foliage — and wait. At most 
their activity consists in a stealthy stalking among the 
leaves until they come within striking distance of their 
victims. The first pair of legs in Mauiida is useless for 




I spci u's, liDwever, have been described. 'i"he colours may 
be restricted to a certain area or may suffuse the whole 
surface of the insect. And when these insects assume 
I their characteristic attitudes amongst vegetation, these 
! colours often give them a curiously flower-like aspect. 
t Now, it is well known that highly specialised flowers rely 
mainly upon the aid of insects to secure cross- 
fertilisation, and that honey is secreted as a 
bait to attract the winged visitors. It has, 
moreover, been demonstrated that the colours 
and markings of flowers attract honey-gathering 
insects. Hearing these facts in mind, it is not 
dilficult to realise that a quaintly shaped and 
brightly coloured Mantis, hanging motionless 
fiinong green foliage, might, at times, be 
mistaken by other insects for a flower. That 
such mistakes actually occur has been vouched 
for by several observers. 

Dr. Wallace mentions an insect {Ilymciwpiis 

liiconiis), discovered by Mr. Wood JViason, 

which attracts insects to their destruction by 

its flower-like shape and pink or white colour. 

Parts of the insect's legs are so flattened as to 

simulate the petals of the supposed flower. In 

this instance, the whole of the Mantis looks 

like an orchid, but in the case of Itloliiim 

diabolicum, from Mozambique, a drawing of 

which is exhibited in the Natural History 

Museum at South Kensington, only the under 

surface of the thorax and fore-limbs have a flower-like 

colour and form. The body, wings, and hind legs are 

greenish or brown, in harmony with the foliage by which 

they are partially hidden when the insect is lying in wait 

for a meal. 

Perhaps the most authentic instance of alluring resem- 
blance is that described on the authority of Dr. J. Ander- 
son. The Mantis is Gongylus gongyloides from Southern 



Raptorial Limbs of a Typical Mantid. 

walking, but is wonderfully modified to serve as 
"clappers" for seizing prey. In the use of these limbs 
the insects are very rapid and dexterous, not only cap- 
turing insects which have settled upon a leaf, but even 
grasping them when actually on the wing. The rows of 
sharp spines with which the modified femur and tibia are 
armed make it impossible for the prey to escape when 
once the Mantis has seized it. 

It has been said that most of the Maniida are either 
green or brown in colour. A few brightly-coloured 




c;fH(y2(/»s (/w«/,'i//on'''s, from Southern India. 



140 



KNOWLEDGE & SCIENTIFIC NEWS. 



[July, 1904. 



India — a species which has been known to naturalists for 
upwards of three centuries, but of whose strange habits 
nothing was discovered until comparatively recent years. 
Living examples of Goiigylus have been thus described :" 
" On looking at the insects from above they did not 
exhibit any very striking features beyond the leaf-like 




Prothorax, Raptorial Limbs and Head of G. Onnniiloidrif in Fiower= 
mimicking pose. The insect is hanging head downwards. 

expansions of the prothorax and the foliaceous append" 
ages of the limbs, both of which, like the upper surface 
of the insect, are coloured green, but on turning to the 
under surface the aspect is entirely different. The leaf- 
like expansion of the prothorax, instead of being green. 
is a clear, pale lavender-violet, with a faint pink bloom 




G. <;on;(j i„i /«, as above. Raptorial Limbs expanded to seize prey. 

along the edges of the leaf, so that this portion of the 
insect has the exact appearance of the corolla of a plant, 
a floral simulation which is perfected by the presence of 
a dark, blackish-brown dot in the centre, over the pro- 
thorax, and which mimics the opening to the tube of a 
corolla. A favourite position of the insect is to hang 
head downwards among a mass of green foliage, and, 
when it does so, it generally remains almost motionless, 

• Pro. Asiat. Soc. Bengal, 1S77, p. 193. 



but, at intervals, evinces a swaying movement as of a 
flower touched by a gentle breeze ; and while in this 
attitude, with its fore-limbs banded violet and black, and 
drawn up in front of the centre of the corolla, the simula- 
tion of a papilionaceous flower is complete. The object 
of the bright colouring of the under surface of the pro- 
thoracic expansion is evident, its purpose being to act as 
a decoy to insects, which, mistaking it for a corolla, fly 
directly into the expectant, sabre-like, raptorial arms of 
the simulator." 







i 




_.*- 


Houlk 




m 






< 




■/;' 




-■ / 


fe) 


y^aaTMO^MA 


A 


















Z:^ Troe Am. ntCr. 


"^ 


^^ 


^m 




x,^ 






^^ TiItlo. 



G, Gor.ni/: ^:'h\'. Key Diagram of Prothorax. Raptorial Limbs and 
Head; and Ventral .Surface: Insect hanging head downwards. 

A more perfect combination of protective and alluring 
resemblance than the above could hardly be conceived. 
The green colouring of the body and legs of the Goiigylus 
harmonises with the foliage amongst which it rests, and 
affords an effective hiding from the sharp eyes of insecti- 
vorous birds. The unusual shape and brightly-coloured 
under side of its protho