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■WE PROPIWTY OF 

^ OF CANAOA. 

TORONTO, ONT, 



SIMPLY WORDED-EXACTLY DESCRIBED. 




Founded by RICHARD A. PROCTOR. 

A) u/ 



"Let Knoirlerlije ijroir from more to more. " 

-TKXXVSOX. 



VOLUME XXI. 

JANUARY TO DECEMBER, i{ 



KNOWLEDGE OFFICE, 326, HIGH HOLBORN, W.C. 

[A// Rights Reserved.] 




I 

I-/ 



KNOWLEDGE 



INDEX 



Abbott, G.. M.R.C.S.— 

Letter on ; " Deserts and tbeir Inhabitants " 

Acetylene Gas 

Note on 

Africa and its Animals 

By R. Lydekker 

Agriculture, A Classic Legacy of 

By John Mii,i.> 110 

Alexander, Boyd, M.B.O.U.— 

A Valley on Siio Nicolau, Cape Verde Islands 

Ant, The Gizzard of the — 

By Walter Wesche ... 



Antarctic Exploration — 

Note on... 

Antlers, Ancient Red Deer — 

By R. Lydekker 

Aurora Borealis, The— 

Letter on ; by J. MR. 

Aurora, Photographic Spectrum of the 

By Edward (,'. Pickering 

Aurora, The Great Sun spot and the— 

By E. W. M.\rNi)ER . 

Australasia, Vegetation of 

Letter on ; by Fred Whitteron 

Battersby, Frances I. — 

An Irish Superstition ... 

Bee, The Hooks on the Mandible of the Honey 

By W.^lter Weschi: .. 

Bees, British, I., II., and III.— 

By Fred. Knock 50,8 

Bees' Mandibles, Hooked Process on— 

Letter on ; by V/ alter Wesche 

Beet Sugar, The, Industry in England— 

By John Mills 

Letter on ; by Sigjiund Stein 

Besley, W. E.- 

Letter on ^'a^iable Stars 

Bessemer, Sir Henry — 

Obituary Notice of ... 



PAGE 

IHIJ 
254 
187 

, 118 
100 
259 
275 
48 
229 
134 
228 
88 
256 
25!t 

2,97 

183 

241 
277 

81 

80 



PAOB 

Binary. A New Spectroscopic 

By EiiwAHi) C. Pickering ... ... ... 134 

Birds. Rare — 

Letter on ; by W. H. S. Monck ... .. 17 

Bird Song, Repetition and Evolution in — 

By C'nARi.E;- .\. Witchell ... .. ... 1116 

Letter on ; by W. Alfred Parr ... 277 

Books, Reviews of— 

Andrcp and hi? Bul'ooii. Bv Heui'i Liicliambri' 

and Alexis Maohurou .. .. ... 87 

Animals, Wild Traits in Tame. By Louis Robinson 64 

Astronomy, a New, for Beginners. By David P. 

Todd ... ... .. ... . . 109 

Astrononiv, Elements of Descriptive. By Herbert 

A. Howe ... ... ... ... ... 233 

Astronomy, The Concise Kuowledgo. By Agnes M. 

Gierke, A. Fowler, and J. EUard Gort- ... IH 

Astronomy, The Klements of. By Charles A. Young Ho 

Audubon and liis Journals. Bv Maria E. Audubon 231 
Birds in London. By W. H. Hudson ... ... 208 

Bond, William Cranch, and )iis son, George Phillips 

Bond, Memorials of. By Edward S. Holdcn ... 134 
Botany, a Text-Book of. By Dr. E. Strasbm-ger. 

and others ... ... ... ... 209 

Carpentry and Joinery, Xotes on. By Thomas Jay 

Evans . "... ... ... ... S6 

Chemistry, a Treatise on (Vol.11. The Metals.). 

By Sir Henry Roscoe and C. Schorlemmer ... 85 

Chemistry. Text-Book of Physical. By Clarence L. 

Speyers ... .. ... ... ... 180 

I'arwin, The Method of. By Frank Cramer ... 20 

Democracy. The Rise of. By J. Holland Rose .. I'J 

Design for Woven Fabrics, Ornamental. By C. 

Stephenson and F. Suddards ... ... 19 

Eclipses, Recent and Coming. By Sir Xorman 

Lockyer ... ... . . ... ... 20 

Education, English National. By H. Holman ... 273 
Electricity in the Service of Man. By R. Wormell 20 

Klectro-Piiysiology. Vol. IL By W. Biedermann 179 
Entomology, Text-Book of. By Alpheus S. Packard 256 
Ethnological Studiesamong the North- West Central 

Queensland Aborigines. By Walter E. Rotli ... 180 
Flora of Perthshire, The. Bv Francis Buchanan 

W. White .. . "... ... ... 157 

Fowling, a History of. By Rev. H. A. Macpherson 110 
Geology, an Introduction to. By Wm. B. Scott... 20 

Geology for Beginners. By W. W. Watts ... 273 

Greece, The First Philosophers of. By Arthur 

Fairbanks ... .. ... . ... 157 

Gutta-Percha, Cantor Lectures on. By Dr. Eugene 

Obaoh ... ... ... ... . 232 

Hunter, John : Man of Science and Surgeon. By 

Stephen Paget ... ... ... ... 20 

Hypnotism, The Elements of. By Ralph Harry 

Vincent ... ... ... 86 

Jaeger, Gustave, >i.D., Researches and Discoveries 

by: Problems of Nature ... ... .. 3!> 

Lite, What is 'f By Frederick Hovenden ... 110 

Light, Visible and Invisible. By Silvauus P. 

Thompson ... ... ... 37 

Magnetism and Electricity, a Treatise on. By Prof. 

Andrew Grav . 13.j 



KNOWLEDGE 



Books, Reviews of — 

Mammals, Reptiles and Fishes of Easex, The. By 

Henry Laver ... ... ... ... 25(> 

Mechanics, Applied. By Joliu Perry ... ... 87 

MechaniA, Theoretieil. By A. E. H. Jjove .. 157 
Memory and its Cultivation. By F. W. Edridge- 

G-reen ... ... ... ... ■■• 135 

Montaigne and Shakespeare. By John M. Robertson 65 ■ 
Moon. William, and his Work for the Blind. By 

John Eutherford ... ... ... ... 180 

' Museums and other subjects connected with Natural 

History, Kssays on. By Sir William Henry Flower 232 
Natural Causes and Supernatural Seemings. B.v 

Henry Maudsley ... ... ... ... f>4 

Natural History (A'ertebrates) of the British Islands, 

A Sketch of the. By F. G. Aflalo ... ... 207 

Naturalist's Directory, The ... ... . ^1 

Nature and a Camera, With. By Richard Keartou 18 
Nature, Some Unrecognized Laws of. By Ignatius 

Singer and Lewis H. Berins ... ... ... 88 

Palieontology, OutUnes of Vertebrate, for Students 

of Zoology. By A. Smith Woodward ... ... 273 

Pare, Ambroise, and his Times. By Stepheu Paget 135 

Peary near the Pole, With. By Eivind Astrup ... 232 

Photography, Kromscop Colour. By Frederic Ives 272 

Plant Life, Glimpses into. By Mrs. Brightwen ... 86 , 

Psychical Research, Studies in. By I' rank Podmore 37 

Psychology, The New. By Dr. E. AV. Scripture ... 03 
Reliquary and Illustrated Archicologist, The. 

A'olum'e for 1897 ... ... ... .-. 38 

Roadside aud River, By. By H. Mead Briggs ... 64 
Smithsonian Institution, 1846-189G ; the History of 

its First Half -Century. Edited by Cxeorge Brown 

Good ... .;. ... ... . . 134 

Sport, The Encvclopiediaof. By the Earl of Suffolk 

and Berkshire, Hedley Peek, and F. G. Aflalo ... 87 

Starland, Stories of. By Mary Proctor ... 272 

Studio, Tlie 273 

iiun's Place in Nature, The. By Sir Norman 

Lockyer ... ... ... ... ... 110 

Thermo-Geographical Studies. By C. L. Mad.sen 156 

Vertebrata, A Classification of. By Hans Gadow... 272 
Vertebrates, Elements of the Comparatiye Anatomy 

of. By Dr. Robert Wiederscheiiu ... ..". 88 
Weltgcbaude, Das: a Popular Treatise on the 

Ueavens. By Dr. M. Wilhelm Meyer ... lids 

AVhite, The Journals of Walter ... 87 
Wonderful Century, The ; its Successes and its 

Failures. By Alfred Russell Wallac-c ... ... 232 

Zoology, A Student's Text-Book of. By Adam 

Sedgwick ... ... ... ... ' ... 15" 

Zoology, Text-Book of. By H. G. Wells ., 257 

Books and Periodicals, Short Notices of— 

Architecture, Muderu. By H. Ileal! icote Statluuii... 135 

Astronomy for the Young. By W. T. Lynn ... 257 

Astronomy, Observational. By Arthur Mee ... 88 
Atoms in Space, The Arrangement of. By J. H. 

Van't Hoff ... ... ... ... 18U 

Bacteria— The Story of Germ Life. By U. W. Cocn 3S 
Barometrical Determination of Heights. By F. J. B. 

Curdeirs ... ... ... ..." ... 233 

Biolog;. . Scientific Method in. By Dr. Elizabeth 

Bluekwell " siS 

Birds, Ackworth. By W. B. Arundel . 274 

Birds, The, of Montreal. By E. D. Wintle ... 2^4 

Botany, Elementary. By Percy Groom ... ... 135 

British Columbia, Year-Book of. By R. E. Gosmll 180 

Carpentry and Joinery. By 1'". C. Webber 274 



PAOB 

Centuries, The ... ... ... ... 135 

Chemical and Physical Calculations, Reform of. By 

C. J. T. Hanssen ... ... ... . . 38 

Chemistry, Elementary. By T. A. Cheetham ... 233 
Cleitistry, First Year's Course of Experimental 

Work in. By Ernest H. Cook .. ... 88 

Chemistry, for Photogi-aphers. By C. P. Townsend 65 
Coinage, Story of the British. By Gertrude Burford 

Rawlings ... ... ... ... ... HI 

Comets, Remarkable. By W. T. Lynn ... ... Ill 

Creation, The Process of. Discovered. By James 

Dunbar ... ... ... ... ... 257 

Earth's History, Outlines of the. By N. S. Thaler 274 

Electricity, Industrial. Edited by A. &. Elliott ... 233 

Fern World, The. By F. G. Heath 274 

French .Self -Taught. By C. A. Thimm ... ... 157 

Geology, Applied. By J. V. Elsden... ... . 274 

Insects, Life-Histories of American. By Clarence 

Moores Weed ... ... ... ... 181 

Intellect, The Building of the. By Douglas M. 

Gaue ... ... ... ... ... 136 

Laboratory Arts, On. By Richard Threlfall ... 209 

London, Guide to. By Emily Constance Cook ... 136 

Machinery of the Uniyci-se, The. By A. E. Dolbear 65 

Magnetism and Electricity. By Dr. K. H. Jude ... 233 

Mind, The Unconscious. By A. T. Schofield ... 274 
Miner's Arithmetic and Mensuration. The. By 

Henry Daries ... ... ... ... 157 

Nature Studies in Elemcntaiy Schools. By Mrs. 

Lucy Wilsou ... ... ... " ... 181 

Observations, Notes on. By Sidney Lupton ... 233 

Organic Chemical Manipulation. By J. T. Hewitt 88 
Photographic Lens, A Simple Guide to the Choice 

of a. By T. R. Dallmeyer ... ... ... 209 

Photography, The Story of. By Alfred T. Story ... 209 
Physics, Elementary, Practical and Theoretical. By 

John G.Kerr " HI 

Physiography for Advanced Students. By A. T. 

Simmons ... ... ... ... IH 

Physiology, Practical. By Alfred F. Blaisdell ... 38 

Pictorial Instruction Object Lcssous. By G. Colomb 65 

Planisphere, Revolving ... ... ... 65 

Plant-Life, Studies in. By Eleanor Hughes-Gibb.. 257 
Poultry for the Table and Market. By W. B. 

Tegetmeier ... ... ... ... ... .. 273 

Process Year-Book for 1898 ... ... ... 157 

Radiography. By E. T. Bottone 274 

Radiography, Practical. By A. AV. Iscnthal and 

H. feuowden AVard ... ... ... ... 233 

Science, Elementary General. By A. T. Simmons 

and L. M. Jones ... ... ... ... 233 

Science, General Elementary. Edited by Wm. 

Briggs ... ... ... ... ... 209 

Science, AA'hat i» Y By the Duke of Argyll ... 257 

Scientific Knowledge, First Y'ear of. By Paul Bert 88 

Seas, The Story of Life in the. By Stephen J. 209 

Hickson ... ... ... ... ... 209 

Sun, The Study of the. By George Mackenzie Knight IIJ 

Telegraphy, AVii-elcss. By Richard Kerr ... 257 

Botanical Studies — 

By A. Vaui.han Jennings 

1. Yaucheria .. 21 

II. Coleochaete .''>4 

III. Jungermannia 115 

IV. Mnium ,. .. 103 
Y. Asplenium . . 211 



KNOWLEDGE 



Botanical Studies ( continued ,- 
By A. \"Ar(;HAx Jenntngs 
YI. Selaginella 
Yll. Abies 
YIII. Lilium 

Botany, Economic — 

By John R. Jackson ... 



25y 
•282 

2S4 

28, 7S, 12t>, 199, 235 



• Canterbury Tales," The Astronomy of the — 

By E. Wu,TER Maunder 205 

Letter on ; by H. J. Lowe . ... 278 

Carr-Gregg, Ivo F. H.— 

Letter on The Urania Sternwarte . . . 3 '> 



Celebes : A Problem in Distribution 

By It. Lyi>ekker 

Chess Column — 

Bv C. I). LococK ... 23, 47, 71, 95, 119, 
167, 191, 215, 239, 203, 

Clarke, Latimer, F.R.S.— 
Obituary Notice of 

Gierke, Miss Agnes M. — 

Variable Stars in Globular Clusters 

Cloud Belts— 

By Wm. Shacki-eton . . 

Cock, W. H.— 

Letter on Dissociation of the Elements 



143. 

287 



27!i 



Cole, Grenville A. J., M.R.LA., F.G.S 

The Floor of a Continent . . -25 

The Structure of Ireland .. 74 

The Mourne Mountains 121 

An Old World Highland .. 170 

An Esker in the Plain 217 

Volcanoes of the North 266 

Comets and Meteors, Notes on- 

By W. F. Denning 10, 46, 70, 94, 118, 142, 

166, 189, 213, 237, 262, 285 
Continent. A Drowned — 

By R. Lydekker . . ... . . 8 

Continent, The Floor of a— 

By Gren\ille A. .J. Cole ... ... ... 25 

Cowries, The Colours of — 

By R. Lydekker .. ... 270 

Crommelin, A. C. D. — 

The New Planet DQ 250 

Crypton — 

Note on ... ... .. lt;o 

Cygni, Herschel Y 37, Photograph of the 
Nebulous Region Round — 

By Is.\.vc Roberts ... . . 253 



Denning, W. F., F.R.A.S.— 

Notes on Comets and Meteors 10, 46, 70, 94, 
142, 166, 189, 213, 237, 262, 
Letter on Mercury 

Deserts and their Inhabitants 

By R. Lydekker 

Letter on ; by G. Abbott 

Draper Catalogue, The — 

Letter on ; by W. H. S. Mox( k 

Earth, The Smell of— 

By G. Cl.xrkk NuTT.u,L 

Letter on ; by G. B. Longstaff 

East, Rev. Arthur — 

The Level of Simspots 

Artificial Facuire ... 

Letter on Photographing through a Fly's Eye 
Letter on a Theory of Refraction in Stmspots 

Easton, C. 

Richard Proctor s Theory of the Universe ... 
A New Theory of the MUky ^^'ay 

Eclipse, Moon in — 

By L. P.\xton ... 

Eclipse, The Prismatic Camera at the Recent — 

By J . EvERSHZD 

Eclipse. The Recent — 

Bv E. W.\lter Maunder ... 101 



118, 
2is5 
13G 



101 
136 



• iO 



257 
•277 



89 
183 
203 
204 



40 

130 

, 155 
38 



Eclipse, Total Solar, January 22nd, 1898 

Eclipse, Total Solar, January 22nd, 1898— 

]'>y E. Walter Maunder ... ... ... 4!) 

Eclipses of the Moon, Errata in Times of^ 

Letter on ; by Lewis Hensley ... ... (Jl 

Eclipses, Total, The Prismatic Camera during — 

By Wm. Shai kleton ... . . .. ... '.) 

Editorial 26". 

Egg Collecting in its Relation to Science — 

Letter on ; by -Joseph P. Nunn ... ... 34 

Elements, Dissociation of 

Letter on : by W. H. Cock ... o5 

Enock, Fred, F.L.S.. F.E.S.— 

British Bees — 1. 50 

British Bees— II. 82 

British Bees— III. . 97 

Insect Miners 178,209 

Esker in the Plain, An — 

By GREN^^LLE A. -J. Cole .. .. 217 

Ethnology at the British Museum — 

By R. Lydekker 223 



KNOWLEDGE 



Evershed, J., F.R.A.S.— 

The Prismatic Camera at the Recent Eclipse 13(i 



Faculae, Artificial — 

By Rev. Arthur East... 

Fishes, Marine Food, Life Histories of the 
British — 

Letter on; by A. T. M.\sterman 

Flanery, David^ 

Letter on Variable Stars 
Letter on Variable Stars 
Letter on U Orionis and S and V Coronie . . 

Flowers, The Affinities of — 

By Felix Osw'ALii 

Fluorine, Liquid — 

By C. F. TowNSEXD 

Letter on; by S. H. Wrii;ht 

Fly's Eye, How to Photograph through a— 

By Fred. W. Saxj^y 

Fly's Eye, Photographing through a — 

Letter on ; by Arthur East ... 



183 



IG 



60 

81 

203 



222 



31 
01 



1S7 



20H 



Fowler, A., F.R.A.S.— 

The Face of the Skv 167, IfH, 214, 238, 263, 2h6 



Gore, J E , F.R.A.S.— 

The Masses and Distances of Biuarv Stars. 



62 



Graham, A.— 

Letter on Testing Multiplication and Division 17 

Green, Jos. F. — 

Letter on Weasel and Young 



Grubb, J. Ernest — 

Letter on A Brilliant Meteor .. 

Haddy, Thos. J.— 

Letter on Artificial Sunspota 

Hall, Maxwell — 

Letter on The Great Sunspot 

Hensley, Lewis- 
Letter on Errata in Times of Eclipses of 
the Moon 



27S 



35 



27'.) 



Ill 



HoUoway, George T.Assoc. R.C.S.Lond.,F.LC.— 

The Petroleum Industry ... 124, l.")l, 169 

Holmes, C. B — 

Letter on Mercury ... ... ... ... 114 

Holmes, Edwin — 

Letter on The Masses and Distances of 

the Binary Stars ... ... ... ... 136 



Hydrogen, Liquefying— 

Note on 

Insect Miners— 

By Freh. Enock 

Ireland. The Structure of— 
By Gre.n\ille A. J. Cole 

Jackson. John R., A.L.S. — 

Economic Botanv 



137 



178, 209 



2s, 73, 126, 
lO'.t, 235 



Jeffery, H. G — 

Letter on The British Trapdoor Spider 

Jenkinson, J. H. — 

Letter on Sunspots .. 

Jennings, A. Yaughan, F.L.S., F.G.S.— 

Botanical Studies— 

I. Vaucheria ... 



II. 

III. 

IV. 
V. 

VI. 
VII. 
VIII. 

Jeryis, Lionel — 



Coleochaste . . . 

Jungermannia 

Mnium 

Asplenium 

Selaginella ... 

Abies 

Lilium 



Serpents and how to recognize them 
The Evolution of the Venom-fang . 



181 



21 

54 
115 
163 
211 

25!» 
282 

284 



91 



Hydrogen Line, A Yariable Bright 

By Edwarh C. Pukerixg 



134 



Karkinokosm, The, or World of Crustacea — 

ByKev.T.R. H. Stehiuxg 1,67,104,145, 197,243 

Laboratory. Handicraft in the 24!* 

Lagerwey. H. W. M., LL.D.— 

Letter on The " Quagga " 203 

Leigh. M. Cordelia- 
Letter on Moon's Halo .. ... ... 278 

Locock, C. D., B.A.— 

Chess Column .. 23,47,71,9.5,119,143,167, 

191, 215, 239, 263, 2H7 
Longstaff'. G. B.— 

Letter on The Smell of Earth 277 

Lowe, H. J. — 

Letter on Astronomy of the " Canterbury 

Tales" 278 

Lydekker, R., B.A., F.R.S.— 

A Drowned Continent... ... .. . . 3 

Ancient Red Deer Antlers . ... . 43 

The Sea-Otter :ind its Extermination 78 

Deserts and their Inhabitants ... ... 101 

Africa and its Animals 137 

Celebes: a Problem in Distribution ... ... 175 

Whale Models at the Natural History Museum 193 

Ethnology at the British Museum ... ... 223 

The Colours of Cowries .' 270 



KNOWLEDGE. 



MacDowall, Alex. B., M.A.— 

Is Weather affected by the Moon ? 
Weather Accounts 
Sunspots and Life 

Markwick, Lieut.-Col. E. E., F.R.A.S.— 

On the Ecjipse Theory of N'ariable Stars . . . 
Letter on the Eclipse Theory of Variable Stars 

Masterraan, A. T. — 

Letter on the Life-Histories of the British 
Marine Food-Fishes 

Maunder, E. Walter, F.R.A.S.— 

The Spectra of Bright Stars 

The Total Solar Eclipse, January 22nd, 1898 

The Recent Eclipse ... 

The Objective Prism, the Flash, and the 

Reversing Layer 
The Astronomy of the " Canterbury Tales" 
The Great Sunspot and the Aurora 

Medals, Geological Society s— 

Note on 

Medals, Royal Geographical Society's— 

Note on 

Mee, Arthur, F.R.A.S.— 

In the Moon's Northern Regions 

Mental Fatigue — 

Note on 

Mercury — 

Letter on ; by C. B. Hol:mes ... 
Letter on ; by W. F. Denxixg 

Messier 33 Trianguli, Photograph of the Spiral 
Nebula — 

By Is-iAc Roberts 

Metals, Smell of — 

Note on . . 

Meteor, A Brilliant — 

Letter on ; by J. Ernest Grubb 
Letter on ; by G. Northover Stretton 

Meteors, The November 

Milky Way, A New Theory of the — 

By C. E.vstox 



128 
231 



15» 
258 



40 

45) 

107 

184 
205 

228 



lb7 



84 



201 



114 

IHfi 



Mills, John — 

A Classic Legacy of Agriculture 
The Beet- Sugar Industry in England 

Mitchell, C. Ainsworth, B.A., F.I.C.— 

The Vinegar Eel 

The Vinegar Fly and the Vinegar Mite 



140, 



27G 



35 
114 



2.V2 



148 
241 



Monck, W. H. S. - 

Letter on Rare Birds ... 
Letter on the Draper Catalogue 
Letter on the Sun's Stellar Magnitude 
Letter on the Eclipse Theory of Variable Stars 
Letter on Variable Stars 

Monium — 

Note on 

Moon's Halo— 

Letter on ; by M. Cordelia Leigh 

Moon's Northern Regions, In the— 
- By Artiu'r Mee 

More, Alexander Goodman, Life of— 
Review of 

Morley, George — 

Christmas Customs of Shakespeare's Green- 
wood . . 

Mourne Mountains, The 

By Grenville A. J. Coi.f. 

Mudflats, From a Hole in the 

By Harry F. Witherby 

Multiplication and Division, Testing- 
Letter on ; by A. Graham 



58 

139 



Museum, South Kensington — 

Notes on ... ... ... 16, 

Natures Finer Forces— 

By H. Snowden Ward 

Nebula and Region Round / Cassiopeise — 

By Isaac Rouerts 

Northampton Institute, Clerkenwell- 

Note on 

Notornis Mantelli 
Note on 

Nunn, Joseph P.— 

Letter on Egg Collecting in its relation to 
Science 

Nuttall, G. Clarke, B.Sc. 

" The Mimic Fires of Ocean ' 

The Smell of Earth 

Occultation of 26 Arietis Observed Photo- 
graphically — 

By Edward C. PicKERi.Nf; 

Occulting Bodies, Light Curves of 

Letter on ; by C. H. Rockwell 

Ocean, The Mimic Fires of — 

By G. Cl.\eke Nutt.\ll 



17 

60 

159 

182 

279 



230 
278 

84 

187 

2C,x 
121 
29 
17 
204 
114 
lOG 
112 
254 

34 



150 
257 



133 



254 



150 



KNOWLEDGE. 



Old-World Highland, An— 

By Grenville A. J. Cole 

Ornithological Notes, British— 

Albino Varieties of Mistle Thrush, Commorj Snipe. 

Woodcock, and Curlew — E. 'Williams ... 
Avocet in Dublin Bay — E. Williams 
Bittern, Little, in County Cork— John J. Wolfe ... 
Bustard, Great, A Norfolk — Thomas Southwell ... 
Bustard, Little, in Norfolk— E. A. Butler 
Buzzard, Bough-legged, in Co. Down— R. Patter.^on 
Capercailie and the Pheasant, on Hybrids between — 

W. Eagle Clarke ... 
Crake, Baillon's, in Caithness— W. Arkwright 
Crane in County Tipperary — W. Johnston 
Crows. Carrion, capturing a Lark — John Cordcaux 
Dipper, Common, at Hillington — Sir W. H. B. 

Ffolkes 

Dove, Ring-, nesting in Edinburgh — A. Craig 
Duck, Ferruginous in West Meath — H. F. W. 
Duck, Long-tailed, in Holderness — John Cordeaux 
Duck, Long-tailed in Ireland — Robert Warren 
Flycatcher, Pied, in Caithness— James Sulherland .. 
Flycatcher, Pied, in Shetland— W. E. Clarke 
Garefowl, The Orcadian home of the— Alfred 

Newton ... ... ... ^... 

Guillemot, Variety of the Common — J. Morley . . . 

Gull, Glaucous, in Isle of Man— P. Ralfe 

Gull, Iceland, in County Sligo in Summer — Robert 

Warren 
Gull, Mediterranean Herring, A New British Gull- 
Thomas Southwell ... 
GuU.Sabine's, in Arran — John Paterson 
Gulls, Lesser Black-baekcd, on the Ei< — W. S. M. 

irrirban .. 
Harrier, Slarsh, in Dumfrieshire — R. Service 
Harrier, Montagii's, breeding in Ireland (correrlio'i) 

John H. Teesdale ... 
Hawfinch in Co. Dowu — R. Patterson 
Hawfinch in Midlothian— W. E. Clarke ... 
Hoopoe in Sussex — Emma L. Turner 
.lackdaws having Domed Nests — W. Wells Bladen 
•Jackdaw's Nest, Curious — S. L. Mosley ... 
Miarants, Spring, Late Arrival of, near Exeter — 

W. S. M. D'Urban ... 
Moorhen chasing Stoat — B.W.Martin ... 
Nesting, Early, of Birds 
Nesting, Early, of Starling, Long-tailed Tit and 

House Sparrow 
Nesting Sites, Change of, of Common Tern and 

Ringed Plover — W. Serle 
Ortolan in Shetland— W. E. Clarke 
Partridge, The Memory of the — J. F. Green 
Parus salicarius, " A hitherto overlooked British 

bird" — Ernst Hartert 
Pastor, Rose-coloured, in West Ross-shire — J. A. 

Fowler 
Peregrines and Herring Gulls — C. J. Wilson 
Phalarope, Grey, in Co. Antrim — R. Patterson 
Phalarope, Grey, near Kilkenny — G. E. H. Barrett- 
Hamilton ... 
Pintail, On the Nesting of the, in the Forth Area- 

W. Evans ... 
Pipit, W^ater, in Carnarvonshire — G. H. CatoD 



170 



112 
112 
G6 
J4 



Pochard, Red-crested, in Westmoreland — H. A. 

Macpherson ... .„ 

Protection of Birds in Scotland — M. L. Lemon 



177 
14 
80 
177 
177 
177 

255 
15 

SI 



177 
.•56 
1.5 



202 
2.34 

;!6 



234 
177 
255 



3fi 
203 



81 

177 

112 

30 
177 



Pufffntis atsimilis and P. olscurus 
Q uail in Sussex — Edwin A. Pratt 
Hedwing, Song of— C. A. Witchell 
Robins and Honeysuckle — C. A. Witchell 
RockaU, Notes on an Expedition to — R, Lloyd 

Praeger 
.Sandpiper, Pectoral, in Kent. — N. F. Ticehurst 
Sandpiper, Pectoral, in Norfolk— J. L. Newman .. 
Sheerwater, The Great, at St. Kilda — Henry Ev ans 
Shrike, Red-backed, in Caithness — James" Sutherland 
Sparrows, House, and Pigeons — F. G. Aflalo 
Squirrels and Birds — C. M. Battersby 
.Swallow, Early Arrival of — E. Sillence 
Swans, Bewick's, in Suffolk — J. F. Green 
Thrush, Hybrid, found in Norway — R. Collett 
Thrush. Mistle, swallowing Droppings of Young — 

Harry F. Witherby... 
Thrush, Mistle, Variation in the Song of — C. A. 

Witchell ... 
Thrush, White's, in Warwickshire — Fet«rSpicer ... 
Tits, Marsh, and Honeysuckle— Mary L. Armitt ... 
Wagtail, White, in County Mayo — Robert Warren 
W'agtails, Migrating, at Peterhead— W. Serle 
Warbler, Barred, in Lincolnshire — G. H. Caton 

Haigh 
Warblers, Melodious, in South-East Devon — Murray 

R. Mathew ... 

Waxwings at Scarborough — J. Morley .. 
Whinchat in Shetland— W. E. Ckrke 
Wigeon Nesting in Yorkshire — W. J. Clarke 
Wigeon, Unusually large Numbers of, in Belfast 

Lough — R. Lloyd Patterson ... 
Woodchat in Susisei— G. W. Bradsliaw 

Oswald, Felix, B.A., B.Sc— 

The Affinities of Flowers 

Parker, Prof. T. Jeffrey- 
Obituary Notice of 

Parr, W. Alfred— 

Letter on Evolution in Bird-Song ... 

Patents, Number of Applications for— 

Note on 

Paxton, L. — 

Letter on Is Weather affected by the Moon ? 
Moon in Eclipse, .January 7th, 1898 



PAGE 

162 

60 
81 



1.5 
277 



177 
15 
234 
162 
277 
203 



81 
277 

SO 
162 
234 



177 
15 

177 



■ SO 
177 



222 

(57 
277 



Petroleum Industry, The— 

By George T. Holloway 

Pickering, Edward C. — 

Stars having large Proper Motion 
Occultation of 26 Arietis observed Photo 

graphically 

A Variable Bright Hydrogen Line . . 
A New Spectroscopic Binary 
Photographic Spectrum of the Aurora 
Xariable Stars of Short Period 

Planet DQ, The New— 

By A. C. D. Ckommelin 

Plants, Self-Irrigation in— 

By Rev. Alex. S. Wilson 



63 



33 
40 



124, 151. 16!) 



8; I 

133 
134 
134 
134 
20r. 



250 



100, 173, 245 



KNOWLEDGE 



Playfair, The Lord- 
Obituary Notice of 

"Quagga; The— 

Letter on ; by H. W. M. Lagerwev 

Quick, James — 

Progress in Kadiography 

Radiography, Progress in— 

l>y •! AMES QrU'K 

Reversing Layer. The Objective Prism, the 
Flash, and the — 

By E. Walter Maunder 

Roberts, Isaac, D.Sc, F.R.S.— 

Photograph of the Spiral Nebula Messier 

33 Trianguli 
Nebula and Region round y Cassiopeise 
Photograph of the Nebulous Region round 

y V 37 Cygni 

Rockwell, Chas. H. — 

Letter on Light Curves of Occulting Bodies 



158 



203 



U7 



247 



181 



39 
106 



253 



254 



Sadler, Herbert, F.R.A.S.— 

The Face of the Sky 
Obituary Notice of 



28, 47, 71, U.",, Ill), 143 
1.".8 



100 



187 



159 



Salvin, Osbert, F.R.S.— 

obituary Notice of ... 158 

Sao Nicolau, Cape Yerde Islands, A Yalley on- 

By Boyd Ales.axder ... 

Saxby. Fred W. - 

How to Photograph through a Fly's Eye 

Science Notes 15, 37, 63, 112, 136. 159, 

204, 230, 254, 275 

Scientific Societies, South -Eastern Union of — 

Note on 

Sea-Otter, and its Extermination, The— 

By E. LVDEKKEK 

Sea-Squirt, The— 

By E. Stenhouse 

Serpents and How to Recognize Them — 

By Lionel Jkkvis 

Shackleton, Wm. F.R.A.S.— 

The Prismatic Camera during Total Eclipses 

Cloud Belts 

Letter on The Level of Sunspots 

Shakespeare's Greenwood, Christmas Customs 
of— 

r>y Georue Morlev 

Sidgreaves, Walter S. J.— 

Letter on Spectrum of -.. Ceti 



220 



9 

56 

112 



268 



61 



Sky, The Face of the— 

By Herbert Sadler 23,47,71,95,119,143 

By A. Fowler . 167, 191, 214, 238, 263, 286 

Sokotra, Expedition to — 

Note on 

Spaoe, Movement in — 

Letter on ; by Ignoramus 

Spectra of Bright Stars, The— 

By E. W.vlter Maunder 



Ceti and y. Herculis, Photo- 



27-i 



18 



40 



Spectra of 
graphed — 

By E. Walter Mai xDER 

Spectra, Prismatic, in Terms of Wave- 
Lengths — 

Note on 

Spectrum of ^ Ceti — 

Letter on ; by Walter Sidgreaves 

Spider, The British Trap-door^ 

Letter on ; by H. G. Jefkery 

Stars having Large Proper Motion- 
By E. C. Pukerix 

Stars, Masses and Distances of Binary— 

By J. E. Gore .. 

Letter on ; by Edwin Holmes 

Stars, On the Eclipse Theory of Variable- 

By Lieut-Col. E. E. M.arkwick 
Letter on ; by W. H. S. Monck 
Letter on ; by H.vrold Whichell^ ■ 
Letter on ; by E. E. Markwick 

Stars, Variable — 

Letter on ; by David Flanery 

Letter on ; by David Flaneky 

Letter on ; by W. E. Besley 

Letter on; by W. H. S. Monck 

Stars, Variable, in Clusters 

Stars, Variable, in Globular Clusters— 

i By Miss Agnes M. Clerke 

! stars. Variable, of Short Period— 

\ By Edw.^rd C. Pickering 

Stebbing, Rev. Thomas R. R.. M.A., F.R.S., 
F.L.S.— 

The Karkinokosm, or World of Crustacea 1, 67, 
104, 145, 197, 243 

1 Stein, Sigmund — 

! Letter on Sugar-Beet Industry in England 277 

Stenhouse, E., A.R.C.S., B.Sc— 

The Sea-Squirt ... 220 



113 



160 



,61 



35 



89 



62 
136 



153 
182 
183 
253 



60 

81 

81 

279 

281 



279 



205 



KNOWLEDGE. 



Stern warte, The Urania — 

Letter on ; by Ivo F. H. Carb-Gregg 

Stretton, G. Northover— 

Letter on A Brilliant ^leteor... 

Sun's Stellar Magnitude, The— 

Letter on ; by W. H. S. Mon( k 

Letter on ; by J. E. Gore 

Ijetter on ; by William Shackleton . . 

Sunspot, The Great — 

Letter on ; by Maxwell Hall 

Sunspot, The Great, and the Aurora- 

By E. W. Maunder 

Sunspots— 

Letter on; by J. H. Jenkixson 

Sunspots, A Theory of Refraction in — 

Letter on ; by Arthur East ... 

Sunspots and Life — 

By Alex. B. MacDowall 

Sunspots, Artificial — 

Letter on ; by Thos. •!. Haddt 

Sunspots, The Level of— 

By Kev. Arthur East... 

Superstition, An Irish — 

By Frances L Battersby 

Tetley, William C— 

Letter on Weasel and Young 

Townsend, C. F., F.C.S.— 

Liquid Fluorine 

Universe, Richard Proctor's Theory of the— 

By C. Easton 

U Orionis and S and U Coronse — 

Letter on ; by D.^ahb Flanert 

Venom-Fang, The Evolution of the — 

By Lionel Jervis 

Vinegar Eel, The— 

By C. AiNswoRTH Mitchell . 



114 



150 I 
150 ^ 
112 



270 



228 



181 



204 



234 



17 



89 



256 



278 



81 



12 



203 



53 



Vinegar Fly. The, and the Vinegar Mite— 

By C. AiN-woRTH Mitchell ... ... 1.30 

Volcanoes of the North — 

By Grenville A. J. Cole 2()6 

Ward, H. Snowden. F.R.P.S.— 

Nature's Finer Forces ... IH 

Weather Accounts — 

By Ale.\. B. M.u-DowALL 128 

Weather, Is, affected by the Moon ?— 

By Alex. B. MacDowall ... 5 

Letters on ; by L. Paxtox and G. E. E. 33 

Weasel and Young — 

Letter on ; by C. A. Witchell ... .. 254 

Letter on ; by -J. F. Green ... ... ... 278 

Letter on ; by W. C. Tetley ... .. 278 

Wesche, Walter — 

Letter on Hooked Process of Bees' Mandibles 183 
The Hooks on the Mandible of the Honey Bee 
and the Gizzard of the Ant 259 

Whale Models at the Natural History Museum— 

By E. Lydekker 193 

Wheat and the Laboratory- 

Xotc on '230 

Whichello, Harold- 
Letter on the Eclipse Theory of Variable Stars 183 

Whitteron, Fred- 
Latter on Vegetation of Australasia ... ... 33 

Wilson, Rev. Alex. S., M.A., B.Sc— 

Self- Irrigation in Plants 160,173,245 

Winnecke, Dr. F. A. T.— 

Obituary Notice of ... ... 21 

Witchell, Charles A.— 

Repetition and Evolution in Bird-Song 



19G 
254 



Letter on Weasel and Young... 

Witherby, Harry F.. F.Z.S.. M.B.O.U.- 

From a Hole in the Mudflats 20 

Wright, S. H.— 

Letter on Liquid Fluorine ... til 

Zoology, The Fourth International Congress 

of 226 



KNOWLEDGE 



INDEX OF THE PRINCIPAL ILLUSTRATIONS. 



Abel Tester for the " Flash Point,' 
The 

Ant, Gizzard of {Ltisiu.t nif/er) 

Antlers, Ancient Red Deer- 
Skull and Antlers of Aged Si'ot^ch 

Red Deer 
Antlers of Red Deer from an Irisli 

Bog 

Antlers of Ancient German Red 

Deer ... ... 

Antlers of German Red Deer with 

Twenty Points 
Antlers of Ancient German Red 

Deer w ith T«ent.v-two Points ... 
Antlers of French Red Deer with 

duplication on the rij;ht siile ... 

Arietis (26), Occultation of ... I 
Audubon ; 

Bee, Hooks on the Mandible of the 

Hoaey i dpU nielifra) ... . : 

Bees, British — 

Colletes Dat'ttsitna 

Andrena ftdva ; CiHasn httinor- 

rhoidalis : Dast/poda hirtipes ... 
y omada succincta ... 
Rose leaves cut by MejachiU 
The Leaf-cutter Bee 
Tnder side and side view of 

Abdomen 
Head of Leaf -cutter Bee ... 
Tunnel of Leaf-cutter Bee 
Third pair of Legs, open and shut 
Leaf -cutter Bee at work . . . 84, 

Tunnel of Leaf-cutter Bee — 

Foundation of first cell 

First side-piece cut and carried, 
and fixed in position 

Second, third, and fuurth side- 
piece 

First gap filled up 

Section of first cell, showing 
pudding and egg 

Three cells 

Section of cells and puddings ... 

Larvae feeding ... 

Pupae 

Five cells, two of them vacated 

Bladder of Bladderwort 223 

Bladderwort Plant in flower .. 2'-l 

Botanical Studies — 

Vaucheria aver-a 22 

Coleocha^te ... ... o5 

.limgermannia ... 1)7 

Mnium .. ... IfiS 

Aspleniuni . .. 212 

Selaginella . 261 

Abies 283 

Lilium ... ... .. 284 

Bushman ... .. 224 

Calamocichla brevipennis, Nest of, 
in a Coffee Tree 101 

Camera, Prismatic, used in Brazil ... [> 



Campbell's (Professor) Observing 
^~^ I Station at Jeur, India 

259 Cloud-Belt, The Equatorial 

I Colours of Cowries, The (full page 
photo;,'raphic plate) ... 



Fluorine, Apparatus for Liquefac- 
tion of . 



32 



ns 

!»8 
9S I 
99 
99 I 
99 
911 : 



Crustacea, The World of— 

A Phyllopod of Palestine (Kstheria 

ffihoni) ... ... ... ... 1 

A pedunculated Cirripede (Lepan 

anaiifera) ... ... ... 2 

A Copepod, parasitic on fish (iecnie- 

olopkus sultana) ... ... 2 

A West Indian Land Crab {Cardi- 

soma guanhumi) ... ... ... 3 

An Arctic Isopod (Gli/ptonolus 

sabini) ... ... ... ... 3 

llemiinerut talpoides ; Dipellt-s 

carri (from Schuchert) ; Dipelti.t 

diplodiscas 67 

CriiptoUthodes tiiplcus 68 

Swimming foot of Amphipod ... 69 
Deep-sea Shrimp taken by the 

Alhatross. Life-size ... ... 104 

Last uropod of the Urothoe ... 105 

Urothoe breiicornis 105 

Second antenna of Baustorius 

arenariu.1 ... ... ... 105 

Platyarthrus Boffmannseggii ... 106 
Nebalia bipes (O. Fabricius) ... 146 
Lepidurus arcticus (VnXhii) ... 146 

Daphnia carinata ... ... ... 147 

Ci/clops Sernilafiis Fischer, 

Figure of 198 

Capilia vitrea (Haeckel) 198 

Calocalanus PIumuIosiu (Claus)... 198 
xfotopterophonts papilio Hesse, 

Figure of 199 

Sphyrion Icevigaium ^<}uay and 

Gaimard). M A.S. ... ... 243 

Notodelph i/s ai/ilis; Thorell. From 

Brady ' 243 

Lomanoticolii insolem. From A. 

Scott 244 

Xicothoi asfaci, Milne-Edwards 

and Audouin .. 244 

Sphoei-onella elegantula, Hansen... 244 
Caligus torpedinis. Chondracan- 

thus horridus. From Heller ... 245 
Diocus gohinus (Fabricius). From 

Steenstrup and Liitken ... 245 

Eclipse Spectra (full page photo- 
graphic [ilate) ... ... ... 132 

Eel, The Vinegar (after Pasteur) ... 53 

Esker at Balrothery, View from the 
road along the 21^ 



Hills, CO. Dublin, 



Esker at Green 
Section in the 21'.' 

Esker at Green Hills, co. Dublin, 
Stratificationof sand at base of the 22i> 

Esker at Tymon Castle, The south- 
west slope of the 219 

Faculae, Artificial and Natural ... 183 



Fly's Eye, How to photograph 
through a 188,189 

Gneiss, Block of, from co. Mayo, 
Ireland ... . 26 

Godwit, The Bar-tailed ... 30 

Guillemots on Cliff 19 

Gulls, Lesser Black-backed ... .. IS 

Holly Fly, Parasite of 210 

Holly Leaf mined by Larva of Phgfo- 

mgzu aquifolii ... ... ... 210 

Ireland, The Structure of— 

Sketch-map of Ireland 76 

Section on the east border of 

CO. Cork ... ... ... ... 77 

.Slievenaman (2364 feet), co. 

Tipperary ... 77 

Killary Harbour, View of the head 
of the fjord of 171 

Leo, the Constellation, with Stellar 
Standards of Reference ... 252 

Light Curves as observed with the 
Photometer ... ... 155 

Light Curves (Theoreticalj of 
different Binary systems 151 

Lunar Alps and their neighbourhood. 
The ... ,85 

Marguerite Fly, The — 

Ovipositing in Leaf ... ... 178 

Sealing up the Egg ; larva and pupa 
of; Egg, part of mine', and pai-a- 
site of ; continuation of mine and 
pupa, in which parasite is 
ovipositing ... ... 179 

Marguerite, Golden, affected with 
■ the maggot " : Leaves of, showing 
Larvae 178 

Milky Way, The, according to Celoria 13 

MilkyWay,The, according to Proctor 12 

Moon in Eclipse, January 7th, 1898, 
Photograph of 40 

Moon, Path of, through the Earth's 
shadow, December 27, 1898 .. 287 

Moon, The Rising and Setting of the 
Harvest 215 

Mourne Granite. Specimen of ... 123 

Mourne Mountains. View in the 
valley of the Kilkeel River, ... 122 

Mudflats, Low Tide on the 29 



KNOWLEDGE. 



Oilfield of Bradford, Derricks in the 

Oil Refinery at Philadelphia 

Oil Well after being Torpedoed 

Orbits of Mars, DQ, and the Earth, 
Relative Disposition of the 

Papuan Girl, Head of 

Peas grown in Experiments on the 
Fixation of Free Nitrogen 

Plants, Self-irrigation in- 
Centrifugal and Centrij)i-t!il Irri- 
gation 
Nodding and Aiirieulate Lpares 
Rain-conducting Channels 
Leaf -cups of Teasel 
Irrigation of the Chick-weed; 
transverse section of Chickweed 
stem ; vertical section of Chick- 
^^'eed stem 
Rotifer inhabiting the hood of a 

Scale-Moss 
Animals inliabiting the axils of 
leaves 

Quarry at Whitehead, Belfast Lough 

Rainfall. Curves of 

Raspberry Shoot affected with " the 
maggot " of Lampronia rvbirlla ... 



125 
152 
126 



161 
161 
162 
173 



174 
246 

246 
207 
130 



Raspberry Shoot, showing Larva of 

Lampro.nn ivh/flla . ... 211 

" Reversing Layer." Photograph 
of the I'l 

Roberts, Dr. Isaac, Full page photo 
graphic Plates by- 
Spiral Nebula Messier 35 Trianguli 39 
NebidiT- near 7 Cassiopeiie ... 106 

Nebula iji V .■H7 Cygni 253 

Rocks, Ridge of Ancient, seen from 
Church Stretton, Shropshire ... -7 

Sea Otter, Upper and Lower Teeth 

of the ... . ~'.< 

Solar Corona, The, 1898, January 22 1.">C. 



Spectra, Comparative 
Reduction of 



Scale for 



100 



Spectra of Ceti (1897, December), 
and a Herculis (1898. February), 
Photographed at Stonyhurst Col- 
lege Observatory ... 113 

Spectrum of an Eclipse, The ... 185 

Spectrum of Ceti 61 

Sun's Corona. The Total Eclipse of, 
January 22, 1898 ... 50, 108, 109 

Sunspot, Ideal Vertical Section of a 113 



PAGE 

Sunspots, A Group of 181, 182 

Sunspots and Life (Diagram of 

Curves) ... 23.". 

Sunspots, The Great Group of (Sep- 
tember 3-15, 1898i 228 

Sunspots, The Level of— 

Symmetrical Spot, Elevated Pen- 
umbra ... ... ... ... 89 

Symmetrical Spot, Penumbra with 

'Dark Margin 89 

I'nsymraetrical Spot, Penumbra 
wanting on one side ... ... 90 

Spot without Penumbra ... ... 90 

Sunspots 90 

Empty Vessel, with black bottom 
just in view ; the same filled with 
water: the same viewed verv 
obliquely '90.91 

Tasmanian Woman 22.5 

Temperature. Curve of Annual ... 129 

Temperature, Curve of Daily ... 129 
Venom Fang, Evolution of the 92, 93 

Vinegar Mite, The 140 

Whale Gallery at the Natural His- 
tory Museum, View in the ... 195 

Wigcon's Nest and Eggs ... 36 



January 1, 1898.] 



KNOWLEDGE. 




Founded in 1881 by RICHARD A. PROCTOR. 



LONDOX : JANUARY 1, 1S9S. 



CONTENTS. 



The Karkinokosm, or World of Crustacea. By the 

Eer. Thomas K. R. SxEnicso, m.a., f.b.s., f.l.s. 

(lUmtrated) 

A Drowned Continent. By K. Ltdekkbb, b.a., f.e.s. ... 
Is Weather affected by the Moon ? By Aiex. B. Mac- 

Do^yArL, M.A. (Illustrated) ... 

Serpents and how to recognize them. By Lioxei .Testis 
The Prismatic Camera during Total Eclipses. By 

Wm. Shackieion, f.b.a.s. {Illustrated.) (Plate) 
Notes on Comets and Meteors. By W. F. DENXiyo, 

F.B.A.S. ... 

Richard Proctors Theory of the Universe. By C. 

Eastox. (Illustrated) ... 

British Ornithological Notes. Conducted by Haert F. 

WiTHKEBT, F.Z.S., M.B.O.r. ... 

Science Notes 

Letters : — A. T. Mastebman ; A. Geaham, m.a. ; Thos 

J. HaBDT ; W. H. S. MOXCK ; ■ lONOBAMrS ' 

Notices of Books. (Illustrated) 

Books Eeceited 

Obituary 

Botanical Studies. — I. Vaucheria. By 
jEyNIXGS, F.L s., F.G.S. {Illusf rated) 

The Face of the Sky for January. 
Sadlke, f.r.a.s. 

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



A. 



By 





U 




1.5 


A. ; Thos. 






16 




18 




21 




21 


Vacshan 






21 




23 





23 



THE KARKINOKOSM, OR WORLD OF 
CRUSTACEA. 

By the Rev. Thomas E. R. Stebbing, .m.a., f.r.s., f.l.s., 

Autlwr of " A History of Cnistiicen," " The Xaturalist of 
Cumbrae," " Report on the Aniphijiodti collected hy H.M..S. 

' Chttllenijer,' " etc. 

DAN CHAUCER'S well of EngUsh undefiled being 
at the disposal of the naturalist, it is often 
thought that only out of pedantry or sheer 
perverseness he tills his story with names and 
terms borrowed from alien tongues, framing 
uncouth compounds out of dead Greek and Latin. Instead 
of saying that the subject now before us is Carcinolotry 
(pronounced Karkinology), or the science of Crustacea, it 
may, therefore, be more acceptable to declare that the 
discussion will turn on the nature of barnacles, water-fleas, 
fish-lice, scuds, hoppers, slaters, hodmandods, shrimps. 



prawns, hermits, lobsters, crayfish, crawfish, and crab- 
fish. The explanation is not quite so compendious as the 
word "Crustacea." It is much longer, and yet does not mean 
so much. It tries to be explicit, and yet remains vague. 
For, on the one hand, many of the popular names above 
given are misleading, since no crustaceans are fishes, and 
some water-fleas and fish-Uce are not crustaceans ; and, 
on the other hand, there are several important groups 
which, because they are seldom seen unless expressly 
sought for, and because they make no direct appeal to the 
pleasure or convenience of mankind, have been passed 
over without receiving any colloquial designation. The 
truth is that no branch of natural history can be handled 
with any degree of thoroughness to the exclusion of its 
own appropriate terms of art ; and, as these are intended 
for cosmopoUtan use, there is an advantage in deriving 
them from the languages of ancient Greece and Rome, 
which can provoke no international jealousies in the breasts 
of modem students. 

The class Crustacea, omitting one controversial group, 
may be conveniently divided into three sub-classes called 
Malacostraca, Entomostraca, Thyrostraca. Of these 
names the first is primeval, and the second of long 
standing. Their meanings have ceased to be of impor- 
tance ; it is only the application of them that is important. 
No one thinks that General Wolfe was especially ferocious, 
or Charles James Fox exceptionally cunning, or that 
Bishop Butler had charge of his master's wine-cellar, 
whatever the circumstances may have been which in the 
past gave rise to their family names. On the same 
principle the term Entomostraca {see Fig. 1), meaning 



,^^^ ■ 



X 



Fig. 1. — Sstheria gihoni (Baird). A Phyllopod of Palestine. 

insects with shells, may well be retained, although the 
animals intended are no longer classed among insects, 
and many of them are totally devoid of shells. There is 
a natural craving for descriptive names in science — for 
names that teach something. That this craving is so 
seldom gratified is not due to ill nature on the part of 
the naturalists. Attempts to indulge it are generally 
failures. The most ingeniously constructed name can 
scarcely be expected to enshrine more than one striking 
characteristic of the group it denominates. Now, research 
is provokingly progressive, and in its progress it is quite 
fond of showing chat the character specified in the ingenious 
name either does not belong to all the members of the 
group, or that it belongs also to the members of several 



KNOWLEDGE. 



[January 1, 1898. 




other groups. Thus the intention of the descriptive word 
is defeated, and, instead of teaching, it leads the unwary 
learner astray. A name like Malaeostraca, signifying 
soft-shelled, which at one time may have usefully dis- 
tinguished lobsters and prawns from the oyster and the 
whelk, is no longer instructive in an enlightened age 
which could not dream of confusing a tasteful crustacean 
with a succulent mollusc. Moreover, some Malaeostraca 
have very hard shells, far surpassing in induration those 
of the Entomostraca and of many Mollusca. The name 
Thyrostraca, meaning shells with doors or valve-shells, 
gives a small item of information about cirripedes, while 
the latter more familiar name refers to the 
fact that the cirri or legs of a barnacle 
have some resemblance to ringlets or 
tresses of hair (see Fig. 2). None the less, 
some of the group have no shells and no 
valves and no cirri. 

In this opening chapter it would be 
highly proper and methodical to define 
the class under discussion in such a way 
that any schoolboy, or a poet, or a 
journalist, on coming casually across 
a Notopteiiipliorus pupilio, for example, 
might, under the guidance of the 
definition, be able at once to exclaim, 
" Lo ! here is a crustacean ! " But nature, 
rejoicing in the penumbra and the twilight, 
and abhorrent of every hard line, takes a 
pleasure in setting definitions at defiance, 
varying the characters within a group, 
and adding here and subtracting there, 
till there is pretty well nothing left which 
all the confederated members can claim 
to have in common. What if some of the 
Crustacea are endowed with a crustaceous 
integument : with gills for breathing ; 
with a heart ; with eyes and brain ; with 
segmented body and limbs ; with bilateral 
symmetry and with powers of locomotion .' 
There are others which are soft-skinned, without gills, eye- 
less, brainless, heartless, shapeless creatures, in a state of 
fixation (see Fig. 3). The difficulty of defining natural groups 
may be illustrated in this way. Suppose that three sets 
of animals have characters so combined that they may be 
represented respectively by the letters nli, be, ck, or by the 
colours red and yellow, yellow and green, green and red. 
The symbols indicate that each set has half its characters 
in common with each of the other sets. Yet there are no 
characters common to all three sets, so as to be available 
for defining a higher group embracing them all. When 
in such circumstances a definition has to resort to negative 
and alternative characters, it may be logically exact, but 
it loses the quality of helpfulness. The beginner, there- 
fore — perhaps the resentful beginner — must say what he 
pleases, and make what he can of the statement that the 
division of the Arthropoda called Crustacea have a seg- 
mented body and limbs at some stage of hfe ; that either 
they have gills or else they breathe in water through their 
skin ; that they have no proper neck ; that they never have 
wings ; and that they are born in locomotive freedom. 
Like insects, they have an integument composed of a sub- 
stance called chitine. This may be extremely flexible, or, 
passing through various degrees of tough and brittle, may, 
by the copious addition of chalky material, attain the hard- 
ness of bone or brick. 

Having come to a provisional agreement with ourselves 
that an almost indefinable congress of startlingly incon- 
gruous-looking creatures are all to be admitted to the 



Fio. 2. — Lepas 
anatifera (Lin- 
DiBus), A pedun- 
culated Cirripede. 



m 



k 



honourable title of crustaceans, we are next tempted to 
ask what natural bond of union, if any, exists for such an 
assemblage. Were they all separately invented just as we 
find them, with their striking contrasts and innumerable 
gradations and subtle resemblances ; or, have they been 
evolved in ramifying lines from a common root ? The 
first hypothesis would leave us rather idiotically gaping 
at what must seem to be the eiiects of an unfathomable 
caprice. Probably, therefore, most thinking men would 
now prefer to explain the genesis of the " Karkinokosm," 
as we know it, on the principle of evolution. By this 
we mean that all the forms, now so amazingly unlike 
one another, are nevertheless descended from common 
ancestors. No one denies that animals are capable of 
reproducing their kind. No one denies that children are 
more or less unlike their parents and unlike one another. 
That these unlikenesses can be to some extent accumulated 
has been proved. That in the course of nature they are 
capable of an accumulation 
so extended and so per- 
manent as to separate a 
man from a mouse, or the 
great Cardi'^dma inM»humi, 
figured on the next page, 
from the worm-like para- 
site Leniaoloplnis stdta7ta,iB 
yet awaiting proof. To the 
principle of evolution it 
matters not how the varia- 
tions are produced, so long 
as some of them can 
sometimes be secured 
against reversion to the 
ancestral pattern. So far 
as the principle is con- 
cerned, it is indifferent 
whether the changes result 
in exalting or degrading 
the character of a species. 
To explain the existing 
constitution of the class 
Crustacea, it must be sup- 
posed that some of its 
members have risen, and 
that some have, after 
rising, fallen. If it cannot 

be proved that all have been evolved from a common 
stock, something can be said for the probability of it : and 
those who are dissatisfied can only be asked to provide 
some other explanation that will better fit the phenomena. 
For the purposes of a natural classification it is the 
history of evolution that is most wanted. We need to 
trace back the ancestry of different forms to the point of 
junction, just as we foUow the twigs of a tree to the 
branch from which they spring, and the branches to the 
common stem. Clearly this can only be done by help of 
the palaeontologists. What the rocks have as yet revealed 
as to the succession in time of crustacean forms has 
recently been represented by Dr. Henry Woodward in a 
kind of fossil tree. Of the undisputed Crustacea he 
recognizes eleven principal branches, and all these he 
draws as running parallel down to the Carboniferous 
period — a period so ancient that in calculating its age 
imagination and arithmetic have to play a drawn game, and 
yet so modern that in it the merry cockroach is already 
in evidence. The disappointing inference is that any 

* See his Presidential Addresses to the Geological Society of 
London, 1895, 1896. 




Fig. 3. — Lernteolophus sultana 
(Xordmann). A Copepod, parasitic 

on Fisli. 



Jaxoary 1, 1898.] 



KNOWLEDGE 



3 



common starting point for all the Crustacea must lie 
indefinitely further back ; and in fact it is not till the pre- 
Cambrian period that all the branches are made to join 
the central stem, while of the earlier points of junction 
between the branches themselves it must be admitted that 



till they melt into an undifferentiated original. Some 
generalized forms are indeed quoted from the record of 
the rocks, but they are few and obscure compared with the 
desires and expectations of the evolutionist. 

In a future cliapter an attempt will be made to show how 




Fig. 4. — Cardisoma r/uanhumi (Latreille). A West Indian Land Crab. 



most are highly oonjectural. The true afiSnities of a modern 
species are often only discovered by careful dissection, and 
such a process is rarely possible with mangled remains in 
an obdurate fossil. Sometimes, when the rock specimens 
are exceptionally clear, the characters displayed are dis- 
tressingly like those familiar to us in living forms. Thus, 
according to Dr. Ortmann, a fossil crawfish from the Upper 

Chalk is more nearly 
related than any 
extant species to 
the modern Linuparis 
tririonits (De Haan) of 
Japanese waters. It 
is imgracious to find 
fault with nature. 
Perhaps the re- 
searches of geology 
are in fault, or per- 
haps there are rays, 
yet waiting to be 
discovered by the 
physicist, which will 
penetrate the secrets 
of an obliterated past. 
Properly to attest the 
work of evolution in 
nature we sorely need 
to recover a series of 
lost pictures. They 
should be a kind of 
dissolving views 
carrying us back to the dawn of life, with the features of 
all existing forms not abruptly but graduaUy fading away, 




a belief in the unity of the class Crustacea may be founded 
on the internal evidence of extant species. That this is 
not, on the face of it, a very simple task, might be inferred 
from the few illustrations here brought together. They 
represent a decapod, an isopod, a phyllopod, a parasitic 
copepod, and a cirripede or cirrhopod, thus ranging from 
the highest to the lowest ranks of the crustacean common- 
wealth. Since nature has ordained that the writer of 
" Hamlet " should have personal identity in common with a 
speechless babe, a land crab need not be too proud to own 
a barnacle for its distant cousin. 



Fio. 5. — Glyptonoliis sabini (Kruyer). 
An Arctic Isopod. 



A DROWNED CONTINENT- 

By K. Lydekkkb, b.a., f.k.s. 

AS many of our readers are doubtless aware, deep 
boring operations are being undertaken in the 
island of Funafuti, in the EUice group of 
Polynesia, with the primary object of ascertaining 
the depth to which coral rock, or limestone of 
coral origin, extends. If it were found that such coral- 
made material extended to depths far below the level at 
which living coral can exist, there would be evidence that 
the island on which the experiment was conducted had 
subsided. And if subsidence were thus proved to have 
taken place in a single island selected almost at random, 
the conclusion could hardly be resisted that the greater 
part, if not the whole, of Polynesia must likewise be a 
subsiding area, or, in other words, the remnants of a 
drowned continent, some of the higher lands of which 
are indicated by the atolls and other islands of the Coral 
Sea. It is, therefore, a favourable opportunity for a few 



KNOWLEDGE 



[Jantjaby 1, 1898. 



words in regard to the permanence or otherwise of the 
great oceanic basins and continental areas of the globe. 
This subject, it need scarcely be said, has not only an 
intense and absorbing interest of its own — for it is difficult 
for anyone except a geologist to fully realize that the solid 
ground on which he stands may have been buried fathoms 
deep beneath the water — but is also one of the utmost 
importance in regard to many puzzling problems connected 
with the present and past geographical distribution of 
terrestrial animals and plants on the surface of the globe. 

Although it might well have been thought that opinion 
in matters scientific would be unlikely to veer suddenly 
round, and after tending strongly in one direction incline 
with equal force in the one immediately opposite, yet 
there are few instances where the swing of the pendulum 
of opinion to one side has been more swiftly followed by its 
oscillation to the other than has been the case in the 
problem of the permanency of continents and oceans. 
When geology first began to take rank among the exact 
sciences, and it was demonstrated that most of the shells 
and other fossils found in the solid rock of many of our 
continents and islands were of marine origin, it was a 
natural, if hasty, conclusion that land and sea had been 
perpetually changing places, and that what is now the 
centre of a continent might comparatively recently have 
been an ocean abyss. Accordingly, when any difficulty 
in finding an adequate explanation in regard to the 
geographical distribution of the animals or plants of two 
or more continents or islands occurred, the aid of an 
" Atlantis " or a " Lemuria " was at once invoked without 
misgiving, and a path thus indicated across which the 
inhabitants of olie isolated area could easily have passed to 
another. 

This was one swing of the pendulum. But as the 
methods of geological observation and investigation became 
more exact and critical, it was soon obvious that, in many 
areas at least, the alternations between sea and land could 
not have been so frequent or so general as had been at 
first supposed. It was, indeed, perfectly true that many 
portions of some of our present continents had for 
long periods been submerged, or had been at intervals 
alternately land and sea. But at the same time it began 
to be realized that the fossiliferous marine deposits 
commonly met with on continents and large islands were 
not of such a nature that they could have been laid down 
in depths at all comparable to those now existing in certain 
parts of the basin of the Atlantic. Even a formation like 
our English chalk, which had been supposed to have 
analogies with the modern Atlantic deposits, appears to 
have been laid down in a sea of much less depth and 
extent, and probably more nearly comparable with the 
modern Mediterranean. Then, again, it was found that 
large tracts in some of our present continents, such as 
Africa and India, had existed as dry land throughout a 
very considerable portion of geological time. Moreover, it 
was asserted that no formations exactly comparable to those 
now in course of deposition in the ocean abysses could be 
detected in any of our existing continents or islands ; while 
it was further urged that in none of the so-called oceanic 
islands (that is, those rising [from great depths at long 
distances from the continental areas) were there either 
fossiliferous or metamorphic rocks similar to those of the 
continents and larger continental islands. 

This was the second swing of the pendulum, and for a 
long period it was confidently asserted that where con- 
tinents now exist there had never been any excessive 
depth of ocean ; and, conversely, that in the areas now 
occupied by the great ocean abysses there had never been 
land during any of the later geological epochs. It was, 



indeed, practically affiimed that wherever the sounding- 
line indicates a Ihcusand fathoms or more of water, there 
sea had been practically always, and that no part of the 
present continents bad ever been submerged to anything 
like that depth. 

Almost as soon as the pendulum of opinion bad attained 
the full limits of its swing in this direction (and this swing 
had been largely due to the influence of geologists and 
physicists), there began to be signs of its return to a less 
extreme position. It was, in the first place, proved that 
a few deposits — and these of comparatively recent date — 
analogous to those of the ocean abysses, do occur in 
certain areas. And, in the second place, it was shown 
that a few oceanic islands do contain rocks like those 
of the continents, and are not solely of volcanic or 
organic origin. Zoological and palfeontological discoveries 
were at the same time making rapid advances ; and the 
students of these branches of science, who had been 
among the foremost in giving the swing of the pen- 
dulum on the side of continental instability its first 
impulse, now began to press their views — only in a 
more moderate manner — in the same direction. Evidence 
had long been accumulating as to the identity of certain 
freshwater formations and their included animal and plant 
remains occurring in South America, South Africa, India, 
and Australia ; and it was urged that during the Secondary 
period of geological history not only was Africa connected 
with India by way of Madagascar and the Seychelles, 
but that laud extended across what is now the South 
Atlantic to connect the Cape with South America, and 
that probably India was likewise joined to Australia by 
way of the Malay archipelago and islands. In fact, there 
seems good evidence to indicate that at this early epoch 
there was a land girdle in comparatively low latitudes 
encircling some three-fourths of the earth's circumference 
from Peru to New Zealand and Fiji. 

Even taking into account the comparatively early date 
of its existence, this girdle of land, the evidence in favour 
of which can scarcely be shaken, gave a heavy blow to 
the adherents of the absolute permanency of continents 
and oceans, as it clearly indicates the comparatively 
modern origin of the basin of the South Atlantic. But this 
is not all. South America, which there is good evidence 
to believe was long cut off from the northern half of the 
New World, shows certains indications of affinity in its 
fauna with that of Europe in early Tertiary times, and to 
a certain extent with that of modern Africa ; and the only 
satisfactory way of explaining these relationships is by 
assuming either the persistence of the land connection 
between the Cape and South America across the South 
Atlantic till a comparatively late geological epoch, or that 
such connection took place further south by means of the 
Antarctic continent. There are several objections, which 
need not be considered here, in regard to the latter alter- 
native ; and since there is other evidence in favour of the 
comparatively recent origin of the South Atlantic depres- 
sion, the persistence of a land connection in lower latitudes 
seems the more probable explanation. 

In addition to all this, there is evidence of a more or 
less intimate relationship between the land faunas of 
Australasia and South America ; and as similar types are 
not met with in Africa, and several of them belong to 
groups unlikely to have endured Antai'ctic cold, it has 
been suggested that America and Australasia were in 
connection at no very remote epoch by way of the Coral 
Sea. It is known, for instance, that some of the Australian 
marsupials are more or less closely allied to others which 
inhabited South America before it was connected with 
North America ; and as no kindred types are met with 



January 1, 1898.] 



KNOWLEDGE. 



either in the latter area, in Europe, or in Africa, a land 
connection by way of the South Pacific, and that at a 
comparatively recent epoch, oilers almost the only satis- 
factory explanation of the means of transit, if the Antarctic 
theory be rejected. And it may be mentioned in passing 
that the acceptance of even the latter would imply a large 
modification from the existing distribution of land and 
water in the southern hemisphere. 

But the evidence for a land connection by way of the 
Pacific does not by any means rest on the testimony of 
marsupials alone. Passing over certain groups, it may 
be mentioned that the earthworms of Australia and New 
Zealand are strangely like those of Patagonia, and have 
no very near relatives in Africa ; while an almost equally 
strong affinity is stated to exist between the Patagonian 
and Polynesian land slugs. Neither of these groups of 
animals are fitted to withstand the cold of high latitudes, 
and it is difficult to see how the members of the second, at 
any rate, could have reached the two areas by any other 
means than a direct land connection. 

Turning now to the brief reports hitherto received as to 
the results of the Funafuti boring, it appears that this 
has been carried far below the limits of coral life, and is 
still in coral limestone. So far, therefore, the advocates 
of the theory that Polynesia is the remains of a sunken 
continent have scored a great triumph ; and although 
there is still the possibility thit some of the atolls in this 
vast area may prove to be perched on the denuded 
summits of extinct submarine volcanoes, even this would 
not interfere with the general conclusion. If deeper 
borings should result in touching rooks more or less 
similar to ordinary continental sedimentary deposits or 
metamorphic crystallines, an even firmer basis would be 
afforded to the hypothesis of subsidence which has now 
received such strikmg confirmation. 

As the result of the boring it appears, then, that there 
is a possibility that the community between the South 
American and Australasian faunas may admit of being 
explained by means of a direct land connection between 
the two areas at a comparatively recent geological date. 
Even, however, if this explanation receive future support 
and acceptation, there are, as in all similar cases, 
still many difficulties with which to contend. One of 
these is the practical absence of all non-volant mammals 
from Polynesia, with the exception of the Solomon group, 
where a few cuscuses and rats are found. But the case 
of the West Indies— where there is every probability that 
there was formerly a large mammalian fauna, the majority 
of which were drowned by submergence — may very likely 
afford the solution of the difficulty. Worms and slugs 
would probably find means of survival in circumstances 
where mammalian life would disappear. This explana- 
tion will, however, clearly not apply in the case of New 
Zealand, where, if mammals had ever existed, their 
remains would almost certainly have been discovered. It 
must be assumed then that, if Polynesia was the route by 
which the faunas of Australia and Patagonia were formerly 
connected. New Zealand was at that time isolated. And, 
indeed, seeing that the hypothetical land connection between 
the areas in question must have existed at a comparatively 
late epoch, it is most likely that the ancient Polynesian 
land was already broken up to a considerable extent into 
islands and archipelagos, so that the main line of con- 
nection may have been but narrow, and from time to time 
interrupted. Indeed, it must almost of necessity have 
been but incomplete and of short duration after the intro- 
duction of modem forms of life, as otherwise the types 
common to Australia and Patagonia would be much 
more numerous than we find to be the case. Hence there 



is no improbability in the suggested isolation of New 
Zealand during the period in question. 

But, putting these interesting speculations aside, the 
results of the Funafuti boring indicate almost without 
doubt that Polynesia is an area of comparatively recent 
subsidence ; and it has already been mentioned that there are 
good reasons for regarding a large part of the basin of the 
South Atlantic as of no great antiquity, whUe the area of the 
Indian Ocean appears to have been considerably enlarged 
during the later geological epochs. Apparently, therefore, 
the great extent of ocean at present characteristic of the 
southern hemisphere is a relatively modern feature. 

Hence it is clear that the extreme views prevalent a few 
years ago as to the absolute permanency of the existing 
continental and oceanic areas clearly stand in need of 
some degree of modification. And what we have now to 
avoid is that the pendulum should not once more take too 
long a swing in the opposite direction. 

So far as the great continental masses of the northern 
hemisphere are concerned, it would appear that portions 
of these have always existed to a greater or lesser extent as 
land. But the great extent and homogeneous character of 
formations like the Mountain Limestone, the Chalk, and 
the Nummulitic Limestone, suggest that sea was much 
more prevalent in this area than it is at present, and that, 
so far as the Old World is concerned, the continental area 
has been growing. The North Atlantic, and probably also 
the North Pacific, may apparently be regarded as basins 
of great antiquity. On the other hand, in the southern 
hemisphere, although Africa, parts of AustraUa, and 
at least some portions of South America, are evidently 
land surfaces of great antiquity, they, together with the 
islands of the Coral Sea, seem to be mere remnants of a 
much more extensive southern continent or continents. 
Conversely the southern oceans have gained in area by 
swallowing up these long-lost lands. Obviously, then, 
although true in a degree, continental permanency has 
by no means been the only factor in the evolution of the 
present surface of the globe. 



IS WEATHER AFFECTED BY THE MOON? 

By Alex. B. MacDowall, m.a. 

THE history of science, in its relation to popular 
beliefs, often affords on both sides curious illus- 
trations of the old adage, Humanum est errare. 
Certain ideas as to the causation of natural phe- 
nomena are widely prevalent. Science steps in to 
examine them. She tests and measures ; sees them to be 
very faulty ; puts them aside as worthless and vain. But 
there comes a time when this judgment has to be revised, 
and considerable grains of truth are found among the 
rubbish. 

There are at present signs, if I mistake not, that the 
denial of hmar influence on weather has been made too 
confidently. 

If we ask any working gardener, or fisherman, or sailor, 
whether he thinks the moon has anything to do with 
weather, he will probably reply with a ready affirmative. 
He may enlarge, in his own wise way, on what weather 
we have to expect if the change of the moon is at this 
hour or that ; if the moon is high or low ; if the new 
moon is on her back or standing up, and so on. Popular 
weather lore on this subject is, we all know, plentiful ; 
and in reading a collection of those sayings we are not 
exactly impressed with their harmony or consistency. 
The pages of Aratus, of Virgil, of Bacon, witness to the 
venerable character of this class of " saws.'' And the 



KNOWLEDG E 



[Januaby 1, 1898. 



North American Indian of to-day considers the position 
of the moon's horns with the same practical interest as 
the Scottish peasant. 

Over all this, it would appear, science shakes her head 
doubtfully. Lunar influence may be probable, but it is not 
proven. Some would even go further. Let us listen to a 
few authoritative utterances on this point. 

In 1895 I find the head of the United States weather 
service remarking that " Lunar periods [in weather] . . . 
have all failed to get a foothold in scientific respect, though 
much time has been put upon them, and they appear 
theoretically probable." 

Prof. W. Morris Davis, author of one of the best recent 
books on meteorology, says : " The control of the weather 
by the moon has long been a favourite idea, but it has not 
been found to bear the test of accurate comparisons of 
weather and lunar phases, except in a very faint and 
imperfect manner." 

Once more, Sir Robert Ball, in his " Story of the 
Heavens," says : " Careful comparison between the state 
of the weather and phases of the moon has quite dis- 



things : a certain definite relation to the moon's phases 
(speaking roughly, a barometric wave to each new and 
each full moon) appears from time to time, and persists, 
perhaps half a year, or more. Then it may disappear 
(from some cause or other), to reappear later on. 

The half-year closing with November, 1897, is, it so 
happens, a very good example. In the accompanying 
diagram the curve is that of the daily barometer at 
Greenwich from -June to November, smoothed with 
averages of five ; that is, each day point of the curve 
represents the average of five daily values (»>.(/., that of the 
3rd of Jime, the five days, one to five, and so on). 

This curve presents, it will be seen, a series of waves 
corresponding remarkably with the moon's phases. Are 
we prepared to affirm that so many coincidences are merely 
fortuitous ? 

This correspondence still persists at the date of writing 
fDecember 7th), and readers of Knowledge may be 
interested to watch further developments. Doubtless, it 
will be masked or obscured ere long : and it may, of 
course, be argued that those intervening periods of irre- 




6 It IB Xt^ 30 6 IX IS ■>h 3o 5 // 17 1.3 %) J^ 10 /<5 22- 2*- V ,o li, 32. 2? J q- /T XI xy 
Curre of Daily Barometer, Greenw-icli, June to Norember, 1897 (smoothed witb Fire-Day Arerages). 



credited the notion that any connection of the kind really 
exists." 

Nevertheless, further study is being given, and will 
doubtless continue to be given, to this interesting question. 
Of recent work upon it, may be mentioned that by 
M. Garrigou-Lagrange, described in a series of papers 
to the Paris Academy. He attributes to the moon's 
influence certain periodical oscillations of the pressure and 
gradients between the Pole and the Equator observed in 
the meridian of Paris. These are superposed on others 
which he considers due to the sim ; and the effect is 
different according as the moon is in a northerly or 
southerly position. 

A simple and direct way of seeking light on the subject 
of lunar influence is to plot a number of curves of daily 
barometric pressure, and see whether any extensive 
correspondence with the moon's phases can be made out. 
Having recently done this with the Greenwich data, I 
would invite attention to some facts which appear to me 
to be highly suggestive. We seem to find this state of 



gularity (or, in some cases, a different kind of regularity) 
suttice to overthrow the evidence of casual connection in 
periods like that here considered. 

Going back as far as 1879, curves of the same type as 
that here given, and of similar extent, will be found in 
1883, 1881, 1889, 1893, and 18ii4. AYhy the corre- 
spondence should come out more clearly at these dates I 
am unable to say. Perhaps some astronomical cause can 
be assigned. 

It is easy to see how an experience of long and regular 
recurrences in weather like that of the years indicated 
may have given rise to a popular conviction that the moon 
influences weather ; and, on the other hand, the fact 
of irregularity subsisting and alternating with regularity 
might account for the negative results often arrived at by 
meteorologists when they have superposed the weather 
data for a long series of limations. 

The presumption of continuance in the type of weather 
indicated, which the above facts appear to warrant, in 
a measure might afford some useful help in forecasting. 



January 1, 1898.] 



KNOWLEDGE. 



SERPENTS AND HOW TO RECOGNIZE THEM. 

By Lionel Jervis. 

THE casual visitor to the Zoological Gardens should 
have little difficulty aa a rule in identifying a 
snake. The name is written underneath in Greek 
or Latin, or half in Greek and half in Latin, or in 
a latinization of local names, as, for instance, in 
the case of the hamadryad, Xaja huniidnis : Najn being, 
I take it, an adaptation of " nag," which is the Hindi 
for cobra, and Ihoiiikihs, I suppose, originates iu the 
bun<i<iriiiii of Russell's " Indian Serpents." 

For all that, the scientific names are better than the 
local cues. Take, for example, the Lucliesis lanceuhitus. 
Perhaps Bothi-o/>s or Ti-iijonocfphatus are more familiar 
titles than the comparatively recent Lachesis, but every- 
one knows what the La-lnsin, Uothrops, or Triiionocejihaltis 
liniceolatus is ; it is, of course, the fer-ile-lance. Com- 
bining the nearly related Lachesiti atrox (the difference 
between the species is so slight that even specialists are 
unable to differentiate offhand), let us see how many local 
names we can find. First there is the fer-di'-lance, then 
follow the rat-tailed pit-viper, the lance-headed viper, 
the deadly snake ("deadly" is a "very vile" prefix, 
quite unworthy of the Zoological Society, who, if I am 
not mistaken, were guilty of it), the jararaca, the yellow 
viper, the whip snake, the Labarri snake, and I dare say 
that there are half a doizen other names in Tropical 
America for this serpent. Nevertheless it is, I think, 
better to leave the local English name alone than to invent 
one. Look at the shielded death adder {Xotechis scut'ttm), 
till recently known as the short-death adder {tlo/din,-- 
lihnlun cHitits). The colonists call it, very happily, the 
tiger or brown-banded snake — a look at the serpent will 
show you why. But here we have " death adder. ' Why 
" death adder " '? The death adder of the colonists, the 
"unqualified" death adder of Regent's Park — the Ac<iii- 
thopis antaicticiis — is about as unlike a tiger snake as 
it well can be. The tiger snake has a cylindrical body, 
tapering into a respectably proportionate tail ; the body 
of the death adder is bloated, and terminates in a short 
compressed tail with a spike at the end of it. In both the 
head is distinct from the neck : that of the tiger snake, 
which resembles a cobra's, very slightly ; that of the death 
adder, which resembles a viper's, very markedly. The 
prefix " shielded " is good enough, but " short" is not so 
happy, considering that the Xotcclns is about twice the 
length of the AcantJwpis. Again, why " purplish death 
adder" instead of "black snake"? Why not confine 
" death adder " to the Acanthopis instead of applying it 
aimlessly to almost every poisonous snake in Australia ? 

•Just one more warning as to the danger of trusting to 
the accuracy or sense of either the English or scientific 
title. Everyone has heard of the beautiful and venomous 
coral snake of Tropical America. It is very brilliantly 
marked with rings of black and red, with thin whitish 
edges to the black rings, and from this the Spanish- 
speaking inhabitants very happily named it the "corral"' 
or " ringed " snake. Some naturalistic genius gets hold 
of this, and, forcing the local name into Latin, calls it 
Elaps o'l-allinKs, thereby misleading people into the idea 
that it is a bright red snake, and called conillinus from its 
resemblance to coral. 

Nevertheless the descriptive label furnishes the accepted 
name, such as it is ; but labels are very little use when 
there are two or three different species in one case, as 
snakes cannot be expected to remain opposite their 
respective descriptions, any more than monkeys. How, 



then, are we to identify them V Coloration is not always a 
sure guide. Look once again at the TmcIiisis lanceolatus. 
It may be of one uniform colour above — grey, brown, 
yellow, reddish, or olive, or it may be any of these colours 
with regular or irregular dark markings, or almost any 
combination of the foregoing. 

In a short article, or even in a small pamphlet, it would 
be impossible to give a " ready recognizer," even for 
snakes which are easily distinguished by specialists. I 
shall therefore content myself with giving an object lesson 
from the small genus Ancistrodoii,'- of the sub-family 
Crotalinm, or pit-vipers. 

The first distinguishing feature is the pit in the loreal 
region, between the eyes and the nose. This pit charac- 
terises a group of poisonous snakes the bite of which is 
sure to entail very unpleasant, often fatal, consequences. 
This group falls into two main divisions — those which have 
rattles on their tails and those which have not. Of course 
a snake with a rattle on its tail is a rattlesnake, and when 
you see a serpent of this kind you are quite safe in saying : 
"That is a poisonous American serpent"; and if it is 
described as ' lotalus tenijini.s, you may, if you like to take 
a slight risk, add: " That is the only one of the kind found 
south of Mexico." But there is a pitfall here, as you are 
quite likely to find the South American rattler described 
as " mohixsu.s" or " huniiluK," and " trn-iiicn.\" has been 
applied to the water-rattle. Oh for an universal classifi- 
cation ! 

The pit-vipers which have no rattle, again, fall into two 
subdivisions : those in which the head is covered with scales, 
the Ldchfsis, and those in which the head is shielded by 
nine symmetrical plates, the Ancistrodon. So, then, if you 
find a serpent with a pit between the eyes and the nose 
(not with two or more pits in the upper lip shields), with 
the head covered with nine shield-like plates, and with no 
rattle on its tail, you have an Ancistrodon. 

Of course the most satisfactory state in which to examine 
a poisonous snake is when it is dead and pickled. If alive, 
the best thing to do is to secure its neck in a snake-loop. 
Fail'ing this, you must content yourself with looking at it 
through glass or wire or from a safe distance. The first 
part of the following descriptions will, therefore, apply when 
the snake can be examined minutely ; the second when it 
can be seen only under comparative difficulties. In some 
cases the colour pattern, together with the data already given 
as to the pit, etc., will be sufficient to identify the serpent. 

First I select the only species of the subdivision in 
which the second upper labial forms part of the border of 
the loreal pit and the sub-caudal shields are in pairs. 

.4. hijpnale.f — By these features you cannot fail to 
recognize the snake on close examination ; otherwise it is 
not so easy to identify. It is only a little bit of a snake, 
with a turned-up nose. The colour is generally dark — 
usually greyish or brown — with or without spots, and the 
markings on the head are ill-defined. The internasals and 
praefrontals, it is true, are broken up into scales, but you 
usually require a magnifying glass to make this out. The 
local name on the west coast of India and in Ceylon, 
where it is found, is the "carawila. " As far as I know, 
there is but little danger attending the bite. 

A. piscirdrw.] — The first of four species in which the 
second upper labial forms part of the border of the pit, 
and some of the sub-caudals are single, some in pairs. 

Remarkable for being the only one of the Ancktrodonin 
which the loreal is absent. The sub-caudals are sometimes 



* Greek : ■• fish-hook toothed." f Oreek : " seudiag to sleep." 
i Latin ; •' fish-eating." 



8 



KNOWLEDGE 



[Januaey 1, 1898. 



all single; the third upper labial is very large, and usually 
enters the eye. 

You are at once struck by the bluntuess of the muzzle 
and the closeness of the eye to the nose, which gives it a 
very vicious appearance. The colour is generally sombre — 
usually a dark slaty brown — with darker cross markings. 
It is said to be of a quarrelsome disposition (some former 
naturalists qualified it as pw/na.r), and it will certainly 
fight with anything that is put into the same case, be it 
rat, snake, or stick. For all that, I have heard that it is 
easily tamed, and becomes, for a snake, quite affectionate. 
It attains a length of about four feet, and is very heavy 
and bulky for its size. It is plentiful in the south-eastern 
United States, where, under the names of " cottonmouth," 
" water mocassin," and " water viper," it enjoys a very bad 
reputation, which was confirmed in my mind by a sad 
story I heard the other day from a trustworthy source. 
A certain good sportsman, while fishing in Florida, had 
made his camp near the water ; and finding, after supper, 
that he had left something in the boat, he desired his 
servant to go and fetch it. The servant, who was native 
to the country, hesitated, saying that he heard a mocassin 
out fishing ; but his master, after listening for some time 
and hearing nothing, pooh-pooh'd the idea. The poor 
fellow reluctantly obeyed, and on his way to the boat was 
struck, and died in a few hours. I gathered from my 
informant that these serpents are quick to resent any 
trespass on their riparian rights, especially at night. 

Second, A. Iiilincatus* — Easily to be identified by the 
markings on the head, Eound the canthug (the sharp 
upper edge of the snout) is a fine yellow line, which 
usually broadens out as it passes behind the eye to its 
termination on the neck : immediately above the mouth, 
but not actually touching it, a broader yellow line, finely 
edged with black, runs along the upper lip from the 
nostril to the corner of the mouth ; there is a similar 
vertical line on the rostral and symphysial shield, which, 
being interpreted, means that a yellow blaok-edged line 
runs from the tip of the snout to the chin. 

Very little is known of this handsome snake owing to 
the detestable climate of its home in Central America. 
There is no big gan^ there to attract sportsmen, to whom 
our collections are so much indebted ; and he is a bold 
naturalist who, in search of rare plants, insects, or reptiles, 
ventures into that fever-striken wilderness. 

Third, A. (•n«<ort(/.r.t— Easily to be recognized on sight 
by its coloration. The ground colour is a bright bur- 
nished light copper, with darker cross binds of a rich 
reddish brown, which are broad at the base and contract 
as they approach the dorsal ridge, thus giving the light 
interspaces the appearance of being broad on the back 
and narrowing on the sides ; the head is generally lighter 
than the ground colour. 

This snake, the copperhead, is probably the most 
dreaded creature m North America, as well as being one 
of the handsomest serpents known — that is, in my opinion ; 
the general effect being more pleasing than the varied 
hues of other more brilliant snakes. It has been classified 
as A. moknscn, and as a good deal of error is connected 
with the name "mocassin,"! I will take this opportunity 
to endeavour to clear it up. There is the true mocassin, 
Tropidnnotus ftixcidtus, a harmless snake of sombre colour; 
the water mocassin already described ; and the upland 
mocassin or copperhead, which is smaller and more lightly 
built than its congener : the two last are often called the 
"mocassin" simply. 

* Latin: "two-lined." ■(■ Latin: "twisting." 

X Mocassin is pronounced "Mokkesin." 



The only accident from a copperhead bite which I ever 
heard from an eye-witness, terminated fatally in a few 
hours, putrefaction setting in almost immediately after 
death. 

Fourth, A. acutiis.* — The sharp point which projects 
horizontally from the tip of the snout makes it impossible 
for anyone to mistake this pit-viper. The upper part of 
the head is very dark brown — the lower, yellow — the two 
colours being sharply divided by a black line which runs 
through the eye ; the general hue of the body is a dark or 
light brown, with very dark diagonal cross bars which 
intersect each other on the dorsal ridge. 

Very little is known about this serpent. There are, 
I believe, only a few specimens in this country, and for 
these we are indebted to the indefatigable Mr. Pratt, who 
obtained them in China. Those that I have seen show it 
to be a heavy, bulky snake ; and as the biggest of these 
specimens is about five feet long, and about as thick as my 
arm, I imigine it to b3 considerably the largest of the 
group. I have been able to ascertain nothing at all about 
the virulence of the poison ; but, I should think, from the 
length of the fangs and the size of the poison channel, 
that a bite would be very dangerous. 

Finally, there are three species in which the upper 
labials are separated from the loreal pit, and the sab- 
caudals are in pairs. 

First, A. }iayh/s\ (with which I combine for the purposes 
of this article the A. blomhofi and the A. intenneditis). — The 
snout is blunt and turned up ; running from the eye along 
the temple is a dark bind with lighter edges, which is a 
little broader than the eye ; on the snout is a dark spot, on 
the top of the head are two more, and on the bick of the 
head are two slanting streaks. Really about the best way 
of recognizing this variety that I can suggest, is a 
negative one. If it has not the characteristic marks of one 
of the other species, then it is a hahfs. It is a smiU, pale, 
dirty-looking viper, usually grey or brown, with no very 
distinctive features. It is found from the coast of China 
to the Caspian Sea, and is the only European pit-viper. 

Second, A, lliinaltiyanus.^^ — Somewhat resembles the 
halijH, but is much darker in colour. On close examina- 
tion it can easily be distinguished by the size of the last 
two upper labials, which are very large and are merged 
into the lower temporals. I have always found a very 
thin black line, with a fine white edge, running from the 
eye to the corner of the mouth, surmounted by a band of 
a darker shade than the ground colour. 

I have not been able to get much information about 
this snake, but it is probably not very dingerous. It is 
found at even greater heights than its near relation, the 
Lavhesis iir)>iticola,i, specimens having been seen at an 
elevation of ten thousand feet. 

Third, A. ylioihistomn. } — A light band runs from the 
eye to the corner of the mouth, below which is a broader 
dark streak with a black edging. This black edging 
skirts the upper border of the posterior upper labials in 
small curves or festoons ; the colour of the lips, from 
which the name is derived, is pink or yellowish. The 
head, viewed from the side, somewhat resembles that of 
the Iiilincatus : but a closer inspection will show that 
the resemblance is only apparent, aud an examination 
of the snout will clear up all doubts, as the rlwdostoina has 

* Latin : " sharp." 

t A title formerlv of a group of East Indian pit-vipers. 
X Himalayan, latinized. 
5 Latin: "living iji the mountains." 
: Ori'eek 1 " rosv -mouthed. " 



January 1, 1898.] 



KNOWLEDGE 



no vertical line on the rostral shield. The ground colour 
is soft red, brown, or grey, with dark, angular, black-edged 
spots, very elegantly arranged. 

In brilliancy and harmony of colour it is, perhaps, the 
most beautiful of the Ancistiodou, though 1 prefer the 
more sober copperhead ; and it is probably the most 
venomous. An acquaintance of mine brought a very bad 
account of the rhiKliistdmn from -Tava, to which island it 
appears to be confined; and Dr. Gunthtr relates that Kubl 
saw a man succumb to the bite in a very few minutes, but 
I can find no record of any experiments with the venom. 
In this respect the liilinniiKx, which also lives under 
the line, may be a possible rival ; but, as I have said, 
I can get no information — that is, reliable information — 
on the point. The peculiar virulence of the venom of 
the I liodoxtomK , which is not by any means a large 
snake, is rather remarkable, as the majority of the East 
Indian pit-vipers do not appear to be very dangerous. 

I have only suggested the lines for a rough-and-ready 
"recognizer," which might be applied to any family of 
serpents. At the same time I can as^sure those who are 
interested in ophidians that a more minute study of this 
or any other genus, will well reward the student ; and that 
during its pursuit they wUl naturally and easily become 
acquainted with those more striking featiujes which I have 
endeavoured to illustrate. 



THE PRISMATIC CAMERA DURING TOTAL 
ECLIPSES. 

By Wji. Shackleton, f.r.a.s. 

NOW that the last eclipse of the century is close 
upon us, and at nearly every observing station a 
prismatic camera is to be employed, it may be 
interesting to give a brief account of some of the 
results which the revival of its use during total 
eclipses has elicited for us. Just in the same way that 
Fraimhofer's method of 
observing stellar spectra 
has been applied to photo- 
graphing the spectra of 
stars with amazing results, 
so the same method of 
placing a prism in front of 
the telescope and observ- 
ing the sun when totally 
eclipsed has, with the aid 
of photography, given 
equally important infor- 
mation. 

The prismatic camera 
as used during eclipses is 
simply an ordinary camera 
(with a lens of from two 
inches aperture and up- 
wards) in front of which 
is placed one or more 
prisms, so that, instead 
of photographing the sun 
directly, the light has first 
to pass through the prism, 
which differentiates the 
composite light of corona, 
prominences, and chromo- 
sphere mto the many 

monochromatic images of which it is composed; and if 
sutiicient dispersion be used these are so separated as not to 
interfere with each other, but are perfectly distinct. 



The advantages of using this slilltss spectroscope over 
one with a slit during a total eclipse is self-evident, for 
by it all the phenomena round the dark moon can be 
analyzed at once with a maximum aperture, whilst in the 
case of an ordinary spectroscope only the small portion 
which the slit crosses can be brought under observation. 

That this is a desideratum one may see when it is 
remembered that it is only possible by intermittent glances 
to observe the eclipsed sun for about two hours in a life- 
time. Fortunately, however, the chromosphere and pro- 
minences, which were enigmas for nearly two centuries, 
have, since the discovery of Lockyer and Janssen in 1868, 
been possible to observe and photograph without an eclipse. 
\Yhen we come to the corona the story is a sadder 
one, for it must have been observed from the time of 
primeval man ; indeed, we have hieroglyphical records of 
it by the ancient Egyptians and Babylonians, and yet we 
know least of all about this the greater bulk of the sun. 
Hence the prismatic camera, for giving us a large survey of 
its chemical constitution, is again the most advantageous 
instrument to employ. 

Not only for quantity, however, but for quality also, is 
it paramount. When photographs are taken with a sht 
spectroscope it is really the slit that is being photographed, 
and any Ught, no matter how it reaches there, is what is 
being investigated. Generally an image of the particular 
part that is required to be studied is focussed on the sht by 
a condensing lens, and this gives the principal effect : but 
besides this there is a general illumination from all 
the other parts, for the light from these is scattered 
and reflected by minute dust particles in our atmosphere, so 
that in addition we have the integrated light from these 
superposed on what we wish to investigate, and, of course, 
the brightest of these extraneous sources gives the greatest 
additional effect. 

In the case of the prismatic camera, however, it is only 
the real images of the eclipsed sun that are focussed on the 
photographic plate, and the general illumination of the 




Prismatic Camera, used in Brazil. 

atmosphere, although equally passing into the camera, has 
no definite outline, and therefore no image can be formed ; 
so it is more scattered still by the prism, and only goes to 



10 



KNOWLEDGE 



[Januaby 1, 1898. 



give a slight general fogging of the plate. Evidently, 
therefore, if we wish to truly sift out the light of the corona 
from that of the prominences the latter instrument must be 
employed. 

Although the prismatic camera has been used during 
eclipses at various times since 1875, it was not until 1893 
that sufficient dispersion and accurate focus were secured 
in order to make use of the differentiation referred to 
above, or it might be that the plates were not sensitive 
enough to record the exceedingly delicate monochromatic 
rings from the lower parts of the corona, which is the only 
part left sufficiently bright after the great deduction that 
must be made for the light giving only a continuous 
spectrum. During the total eclipse of 1893 photographs 
were taken in West Africa by Mr. A. Fowler, and in Brazil 
by myself, which showed that the coronal light gave 
rise to no H or K radiations of calcium — ^that the 
prominences on the sun at that time had no 1474 K light : 
and although this line, sometimes seen in eruptive 
prominences, might be accounted for by supposing that it 
really is the base of the corona which is being observed, or 
that coronal matter has got entangled with the great 
disturbances taking place, still in one such prominence 
during that eclipse no trace of it could be found. Again, 
in the eclipse of 1896, more than three years later, 
the photographs show the same thing ; so we await with 
interest the results of the coming eclipse, to see if in 
passing from a maximum to a minimum sunspot period 
any change takes place in the constitution of the corona. 

If a comparison be made of the K (calcium) and 1474 K 
rings with a picture of the eclipsed sun, it is clearly 
seen that 1474 K is truly coronal, and that H and K, 
which are identical with each other, are solely due to the 
prominences. 

Had these facts been sufficiently well established in 
1893, M. Deslandres might not have tried in vain to 
determine the rotation of the corona by photographing 
the relative displacement of the II and K lines on opposite 
limbs of the sun. In the last number of Knowledge it 
was stated that Mr. Newall is going to try to make the 
same observation, using a "bright line near (1, of whose 
coronal nature there can be no doubt." Let us hope he has 
consulted the records of the prismatic camera before doing 
this, for although one such line was tabulated at ^ 4232-8 
by Schuster in 1886 as being the brightest in the photo- 
graphical region, the results of 1893 and 1896 show that 
a bright line near H, A 3987, is more intense than this, and 
in fact is the next strongest line to the coronal Une 
(1474 K) itself. This will be seen on examining the 
photograph taken near mid-totality, and reproduced here 
in the plate by the kind permission of the Royal Society. 

So far we have examined the capabilities of the pris- 
matic camera for giving us information about the parts 
of the sun comparatively well removed from the photo- 
sphere ; let us now turn our attention to see what can 
be done with it for the investigation of those vapours 
which lie closer in, in order to test Kirchoff's theory 
" that the absorption which produces the dark Fraunhofer 
lines takes place in a thin stratum, or reversing layer, as it 
has often been called, adjacent to the photosphere." 

In a total eclipse of the sun, at the moment the 
advancing moon just covers the sun's disc, the solar 
atmosphere of course projects above the dark edge, and at 
that moment the reversing layer will be isolated for only a 
very few seconds. If, now, at this precise instant, a photo- 
graph be taken with the prismatic camera, we shall have 
the spectrum of this shallow layer, chromosphere and 
corona ; but from the form of the arcs and their appearance 
or non-appearance in later photographs, we shall be able 



to separate the integrated effect into its indindual parts. 
From the very nature of this layer and the inequalities in 
the moon's position, the difficulties in the way of making 
the exceedingly fine adjustment of placing a ^/'> upon this 
point of disappearance are almost insurmountable; in fact, 
so great are they that it was not until the apphcation of 
the prismatic camera, which requires no such nicety of 
adjustment, that there was any permanent record of this 
low-lying stratum. 

Except at an eclipse it has not yet been found possible 
to observe this bright line spectrum, because it is over- 
powered by the aerial illumination of our own atmosphere 
so spectroscopists are the more anxious to make the most 
of every echpse to settle at least this one point. With 
this end in view many prismatic cameras have been 
directed to the eclipsed sun, but it was not until 1893 
that anything like the base of the sun's atmosphere was 
photographed. 

The difficulties of placing a slit on a point have been 
mentioned previously, but not only is there that to contend 
with, but also, no matter what instrument be used, the 
exposure must be made at the precise moment the sun's 
disc is covered. To do this, Sir Norman Lockyer, during 
the eclipse of 1896 in Norway, instituted a " running 
plate," which took a series of snapshots just before and 
going on till the critical moment had passed — in fact, a 
sort of kinematograph arrangement. Unfortunately, how- 
ever, the weather was unfavourable to let us see what 
results this method would give. Mr. Evershed, also, in 
clouded-out Norway, and myself, in Novaya Zemlya, rehed 
more on the exact determination of the proper instant, 
and then making a short exposure. What such a photo- 
graph is Like, and how far it agrees with a reversed solar 
spectrum, can be gathered from the plate, which is a repro- 
duction of the Novaya Zemlya photograph. Of course 
any comparison must be made with a spectrum obtained 
by a similar instrument, for it would obviously be fallacious 
to compare a spectrum taken with only a moderate-sized 
spectroscope, making clear to us only a few hundreds of 
lines, with such a spectrum as that taken with a Rowland 
grating, which reveals in tin snine sunliiiht as many tens of 
thousands of lines. Therefore, the only way of absolutely 
proving that every fine dark line is reversed would be to 
photograph this layer with a Eowland grating, which, with 
our present appliances and the short duration of visibility, 
is nearly impossible : but this is to be tried by Prof. Michie 
Smith during the forthcoming eclipse. Still, notwith- 
standing these difficulties, the investigation of the Imes 
in the photograph is proceeding at the Solar Physics 
Observatory, South Kensington; but, probably, before it 
is finished we shall have many such photographs, with 
more powerful instruments, from India, where the sun will 
be bombarded, not by one only, but by at least half a 
dozen prismatic cameras. 

With such possibilities in an eclipse, no wonder during 
such times that the sun monopolises the attention of 
astronomers, not only for the secrets he has to divulge of 
himself, but also for the key he may possibly give to cipher 
the constitution of other countless suns more remote. 



NOTES ON COMETS AND METEORS. 

By W. F. Dennujg, f.k.a.s. 

Comets. — 1897 has afl'orded only one new comet — that 
discovered by Perrine on October 16th. When first seen, 
the comet was placed in the south-east region of Camelo- 
pardus and moving north-west ; it has since traversed 
Cassiopeia, Cepheus, and Draco. Early in January, 



January 1, 1898.] 



KNOWLEDGE 



11 



1808, the comet will be almost stationary at a point 
six degrees south by east of y Draoonis, its apparent 
displacement beinf? only ten minutes of arc per day. 
Its brightness will be 04, as compared with that 
(adopted as 10) at discovery. The elements show its 
inclination to be sixty-nine degrees, whence we may infer 
that its orbit does not deviate much from a parabola. The 
physical aspect of the comet has been interesting, for it 
presented a nucleus, coma, and tail. On October 25th, as 
observed by Mr. F. W. Longbottom, at Chester, with an 
eighteen and a half inch Calver, the total length of the 
tail was twenty minutes of arc, and the comet was estimated 
not quite equivalent in brightness to a ninth magnitude 
star. The tail was tapering, not fan-like, and stars showed 
brightly through it on October 80th. 

Several periodical comets were due in 1897, but only one 
of these was observed, viz., D'Arrest's, which was picked 
up by Perrine on June 'iSth, more than a month after its 
perihelion passage. Spitaler's comet of 1800, and Tempel- 
Swift's comet of 1869-80, also returned to perihelion in 
the spring, but the conditions were too unfavourable for 
them to be observed. 

In 1898 five periodical comets are due. Pons-Winnecke's 
arrives at perihelion in March, Encke's in May, Swift's 
(1880, VI.) and Wolfs in June, and Tempel's (18G7, II.) 
in September. The circumstances attending the return of 
these several objects are by no means good, and in most 
cases they are likely to escape observation unless some of 
the large telescopes at present in use are employed in 
searching for them. 

Mr. C. Hildebrand gives the following ephemeris of 
Pons-Winnecke's comet : — 



January 



2 


15 18 24 


- 3° 55-3' 


6 


15 82 53 


- 4° 52-3' 


10 


15 47 58 


- 5° 40-8 


14 


16 8 40 


- 6° 46-1 


18 


16 20 


- 7° 42-1 


22 


16 36 59 


^ 8° 87-0' 


26 


16 54 36 


- 9° 80-8 


80 


17 12 49 


-10° 21-3 



The diurnal motion is therefore about one degree east- 
wards, and during the month it carries the comet through 
Libra and Opiucbus. 

It is remarkable how the stream of cometary discovery 
runs continuously on. No sooner do one or two suc- 
cessful sweepers leave the field than others step in and 
pursue the work. Messier, Mechain, and Caroline 
Herschel, in the latter part of the last century, were 
succeeded by Pons early in this. He in turn was followed 
by Tempel, Winnecke, Borrelly, Coggia, and Swift. Then 
Barnard and Brooks almost monopolized the field for 
twelve years. To-day Perrine may be regarded as the 
comet finder \uir e.vcelh nee. for he has worthily emulated 
Barnard's former discoveries at the Lick Observatory, 
and has found five new comets within the last three 
years. 

Meteors. — The November Leonids of 1897 very generally 
disappointed expectation. Cloudy weather and moonlight 
were certainly responsible in a great measure for this, and, 
moreover, there is no doubt that an exaggerated idea as 
to the probable intensity of the display was encouraged 
by the majority of those who looked for it. On the basis 
of reports supplied by eye-witnesses of the phenomena 
of 1831 and 1804, it was predicted that the shower might 
equal a rich return of the August Perseids, furnishing, 
perhaps, one hundred meteors per hour for an observer. 



The time of maximum was mentioned as uncertain, but 
as sure to be included in the mornings of November 14th 
and 15th. As events happened the first of these periods 
was partly clear, while the next morning was cloudy 
nearly everywhere. Meteors were comparatively rare 
during the whole night of the 13th, and clouds hid those 
visible during the following night. In France and America, 
as well as in England, the experience appears to have been 
very similar. At a few places, where the sky was clear 
on the morning of November loth, the Leonids were both 
numerous and brilliant. At Dumfries, two observers 
(ignorant of the expected display) were struck at the 
extraordinary prevalence of shooting stars, and estimated 
the visible number as ten per minute. Another observer, 
at Loughborough, saw a considerable number of meteors, 
including five of great brilliancy, and the time of their 
maximum frequency seems to have been at about •") a.m. 
A third observer at Dumfries had his attention arrested 
by the surprising frequency of meteors, and states that 
more than five per minute were perceptible. At Derby 
meteors were so abundant as to cause special remark. 
Eighteen fine ones were noticed between 3h. 30m. and 
5h. A.M., and these included two nearly as bright as the 
full moon. Prof. Lewis Swift also reports from Echo 
Moimtain, California, that " the Leonids made their appear- 
ance on the morning of November 15th, ninety-seven 
having been counted by one person." From these and 
other corroborative accounts it is certain the shower was 
quite as abundant as expected, and, at places were the sky 
was clear, sufficiently striking to attract particular attention 
notwithstanding the moonlight. The idea that the display 
failed to present itself is due to a misapprehension. On 
the preceding night the experience of observers seems 
to have been practically unanimous in describing the 
meteors as scarcely more numerous than on an ordinary 
November night. 

Prof. E. C. Pickering, of Harvard, states that the 
observers at the observatory at Cambridge, ilass., counted 
only ninety meteors during the night of the 13th, but that 
these were nearly all Leonids. Prof. 0. Stone, of Richmond, 
Va., says that on November 13th several meteors were 
seen from the direction of Leo ; one of them was several 
times brighter than Venus, and travelled along an arc of 
ninety degrees, leaving a streak forty degrees in length. 
The following night was cloudy, and nothing could be seen. 
Prof. Barnard, at the Yerkes Observatory, saw nothing 
on November 18th and 14th, as clouds and rain prevailed 
each night. In England a few meteors were seen on 
November 13th, but they caU for no special remark. 
Dr. W. J. S. Lockyer, of South Kensington, recorded a 
number of paths, and others were registered by Mr. 
Salmon, of South Croydon, and Mr. Besley at Westminster. 
These materials show that, though the Leonids returned on 
the night of November 13th, the shower was very feebly 
represented. These and many other observers were 
baulked by clouds in their efforts to secure observations 
on the night of November 14th. At Bristol the sky was 
overcast throughout, though at 5 a. jr. on the 15th the 
clouds became thinner, and the moon shone faintly through 
them, but no meteors could have been observed unless they 
were of great brilliancy. 

Observers of meteors will be interested in watching for 
the January shower from Quadrans, usually visible on the 
2nd of that month. The moon will, however, partly 
interfere in the evening, and the best time to observe the 
display will be between 3 and 6 a.m. on January 2nd. 
The radiant is at 280° + 52°, and the shower is often 
a conspicuous one, furnishing rather swift, long-pathed 
meteors. 



12 



KNOWLEDGE 



[Jantabt 1, 1898. 



RICHARD PROCTOR'S THEORY OF THE 
UNIVERSE. 

By C. Easton. 

RICHARD PKOCTOR, the founder of this magazine, 
amongst the other services that he has rendered 
to science, deserves the credit of being the first 
to offer a sohition of the problem of the structure 
of the heavens by studying it from a general 
point of view, whilst at the same time basing his theory 
on direct observation. Huyghens, Thomas Wright, Kant, 
Lambert, and others, had already touched on this great 
problem, but they had to content themselves with 
reasonings; they misused the arguments per annlofiiuin, 
having very few facts to go upon. The two Herschels 
collected an enormous quantity of facts and precise data 
relating to the problem, but they were reluctant to 
draw from them any definite conclusions. Sir William 
Herschel himself abandoned a considerable number of his 
early ideas pn the structure of the heavens, although he 
did not declare in a definite manner what changes must 
be made in it. As for his son, he demonstrated the 
untenability of the cloven iliac theoni, and of the funda- 
mental suppositions made by his illustrious father, 
especially in the face of the evidence drawn by Sir John 
himself from his telescopic observations of the Milky Way. 
Contrary to what has been often said. Sir John Herschel 
has stated expressly and exclusively — at least in his books 
— the theory generally attributed to him of the galactic 
ring, although he seems to have found in this theory the 
fewest obstacles to the explanation of the phenomenon. 

From the beginning. Proctor insisted, when discussing 
the conceptions of Sir John Herschel, that neither the 
cloven disc theory nor the theory of a galactic ring could 
adequately explain the observed facts. In the case of the 
second theory, Proctor only indicates its insufiiciency in a 
general manner. Even the principal features of the Galaxy, 
he says, offer too great difficulties for the annular theory, 
and he boldly sketches a more complicated figure, which, he 
says, replaces with advantage Sir John Herschels theory 
explaining the principal details of the ililky Way. 

Whilst recognizing that the extreme complexity of the 
details in the Milky Way may never perhaps allow of a 
complete solution, Proctor was convinced that " the bolder 
and more striking features of that circle may be studied 
with a better hope of their being successfully interpreted." 
He has been reproached with too much audacity, and, 
indeed, one hesitates to subscribe with Proctor to " the 
spiral curve, which [as] depicted seems so satisfactorily 
to account for several of the more strikmg features of the 
Milky Way as to suggest the idea that it corresponds some- 
what closely to the real figure of that star-stream." But it 
seems to me that the advantages of his researches are 
much superior to the disadvantages. Those who approach 
with hesitation and prudence by far other ways will not be 



the Galaxy, which .... would come to be 

regarded as a Bat ring, or aome other re-entering form of immense 
and irregular bi eadth and thickness . . . ." (Sir John Herschel, 
" Outlines," § 788.) He prefers to represent the Milky Way as of an 
annular form, but he takes care not to pronounce definitely on this. 
" • • ■ an impression amounting almost to convietion tliat the 
Milty Way is not a mere stratum, but annular ; or at least that our 
system is placed within one of tlie poorer or almost vacant parts of 
its general mass ..." (Mary Somerville, " The Connexion of the 
Physical Sciences," 1846, p. 419.) 

In speaking of the lateral offsets which quit the main stream of 
tlie Milky Way, and which he regards as the " couTexities of curved 
surfaces Tiewod tangcntially, or planes seen edgeways " (" Outlines," 
§ 792), he eridcntly docs not trouble to bring them 'into accord with 
the theory of a galactic ring. 



led astray by the errors of Proctor's method ; and, on the 
other hand, pioneers of science such as he exercise a great 
moral influence — their digressions, though sometimes over- 
bold, refresh and stimulate the zeal of others. 

This gigantic arch of the Milky Way, spreading out before 
all eyes the sublime enigma of its starry ramifications, seems 
to defy the indefatigable seekers bending over their calcu- 
lations. Let others strive to draw some evidence of the 
aspect of the Milky Way from its chief outlines. 

However, Proctor would doubtless himself recognize 
to-day that his theory does not now correspond with the 
actual state of science ; and it is strange that in treatises 
of astronomy his well-known drawing is reproduced as if 
the theory could still be accepted, although more than one 
judicious remark of Proctor's preserves his reputation. At 
the period when he formulated his theory, Proctor had not 
at his disposal, in short, any but the results obtained by 
the two Herschels and by F. G. W. Struve : and, besides, 
the work of the latter was soon reduced by Encke to its 
.just proportions — that is to say, to a negative result, or one 
nearly so. Almost all the modern work in this branch of 
astronomy has been done since Proctor's time — that of 
Heis,Houzeau, Gould, Celoria, Kapteyn, Ristenpart, Plass- 
mann, etc. ; and in particular, though basing his researches 
on the constitution of the Milky Way, he could not con- 
sult either the admirable photographs of Barnard, Wolf, 
Roberts, Russell, nor the modern drawings of it — that is 
to say, that he possessed scarcely any facts about the whole 
northern half of the zone. 

Also, the explanation furnished for the figure imagined 
by Proctor could not be considered as satisfactory to-day, 

(^ oc 4 -i * op. 



t^^ 



4--:^^..^ 



■•fc s 



% "^'Sht^rtoa*' 






^- --^^ _,-' <y 

d'tw.x 
The Milky Way according to Proctor. 

even for the main lines of the Galaxy. Many of his obser- 
vations, however, are still valuable. When he says that 
where the line of sight is directed tangentially to either 
loop, the Milky Way may be expected to have greater 
width than elsewhere, he furnishes the best explanation 
of the curious fan-shaped expansions of the Milky Way on 
each side of the no less remarkable gap in Argo. His 
explanation of the Coal Sack in Crux — "the apparent inter- 

* Sir John Herschel, although he described with iuuch particularitv 
the southern half of the Milky Way, treated rather lightly the 
northern parts. Thus he says in his "Cape Observations," p. 386, 
speaking of the region in the Eagle, which is nevertheless curious : 
" After which |^A Aquilae] this main stream runs northward through 
Aquila without any fui-ther distinguishing feature. . . ." 



January 1, 1898.] 



KNOWLEDGE 



13 



crossing of the two contorted streams which really are at 
different distances from the eye " — is possible but not very 
probable, I think, after the evidence furnished lately by 
Gould and Russell. I do not think it was necessary in 
this case to turn aside from Sir John Herschcl's opinion 
that the Mility Way in the neighbourhood of tlie Coal Sack 
is just " a distant mass of comparatively moderate thick- 
ness, simply perforated from side to side," or as an oval 
vacuity which is seen " foreshortened in a distant fore- 
shortened area." (" Outlines," ; 702.) 

There is doubtless much truth in Proctor's supposition 
of the branches which are detached from the main stream 
of the Mdky Way, and which penetrate into the neighbour- 
hood of the sun, and of the less important ramifications 
which spring up at different points of the galactic course. 
But as regards the general reasoning followed by Proctor 
in comparing bis figure with the aspect of the Milky Way, 
he is fundamentally in error ; and this is an interesting 
point, since Sir John Herschel had already made a similar 
mistake. Herschel says that the brilliant and well-defined 
part of the Jlilky Way about Argo and Crux " conveys 
strongly the impression of a greater proximity"; and he 
deduces from this that the sun occupies an excentric 
position in the interior of the Milky Way, which is nearer 
to the southern than to the northern part of its circuit. 
Taking up this argument and amplifying it. Proctor admits 
that the stream grows gradually fainter with increase of 
distance towards Canis Jlinor and Monoceros ; and in 
speaking of the brilliant portions of the Galaxy in Aquila 
and Sagittarius he is satisfied that " this part, which is so 
very bright, corresponds to the part which my spiral brings 
so venj )b ar to the sun." 

But we should see precisely the opposite in this case. 
Sir John Herschel and Proctor have been too much taken 
up with the idea of a stream, of a " distant mass," which 
they represent as continuous, like a band of cloth, whose 
details are perceived with more clearness the nearer they 
are. But the phenomenon of the Galaxy is of quite a 
different nature. As long as the brightness of each indi- 
vidual star is of great importance, and their mutual 
distances which we see projected are insignificant, the 
reasoning of Sir John Herschel and of Proctor holds good. 
But it is, above all, the closeness. In projection, of the 
small stars in the Milky Way which produces the optical 
phenomenon of a galactic gleam. The individual brilliancy 
matters little. This can be easily demonstrated. From 
the gauges of Sir William Herschel and from the star- 
counts of G. Celoria, it follows that the number of stars 
sufficiently brilliant (seventh to eleventh magnitude) which 
take part in the formation of the lacteal light, is much 
more considerable in the region of Monoceros than of 
Aquila, and in spite of the fact that the Milky Way is, 
without gainsay, much more luminous in the latter portion 
of the sky than in the former. Then, the abundance of 
stars in certain lacteal regions (Scutum, Cygnus, etc.) is 
so great that the relatively bright stars form but an insig- 
nificant part of it distributed here and there among the 
multitudes of small stars. But, whatever may be the 
number of stars necessary for this, the stars are snfB- 
ciently near each other in perspective for their collective 
light to produce a strong enough impression on the 
extremity of our optic nerve and give us the impression of 
the lacteal gleam— an impression that could not be pro- 
duced by stars each much more brilliant than the others 
united, but their projections too distant for their images 
to fall on the same nerve bundle in the retina. 

The same thing is seen when a celestial object is resolved 
into stars which had until then appeared nebulous. Thus 
the parts of the Milky Way which are nearest to ua would 



appear by the same rule vague, large, and rich in stars 
relatively bright, whilst the distant portions of the zone 
would appear more crowded and better defined — more 
luminous in themselves, though numbering fewer brilliant 
stars. One could easily represent this appearance by 



Qa.'i 3ti 



'/- 



^^' y' 






^"B:!"^^. 



b .■'■ 






1 <> 
2 I ■■■'-.' .'=•:- * ■ ■■■■ I «> 



\ %%. 



\' .■•>'■ > 
■-■■ * / 



The Milky Way according to Celoria. 

imagining oneself within a huge circle of trees, nearer to 
one part of the circumference than to the rest. In the 
near part the trees do not form a continuous band, whilst 
they are confounded in one straight dark line in the 
further portions of the circle. 

I have written at some length on this point because it 
undermines the reasoning of Proctor in more than one 
particular, and also demonstrates that one remark of Sir 
John Herschel, often quoted, rests on an erroneous argu- 
ment, and that to my knowledge these points have been 
raised before. 

After what I have just said it would be superfluous to 
criticise in detail the " spiral " of Proctor. For the rest, 
even if they furnished a perfect explanation of all the 
principal features which Proctor finds in the Milky Way, 
they could no longer serve, now that the principal features 
of the galactic zone in the two hemispheres — thanks to 
the drawings and to the photographs,* and in despite even 
of the dift'erences that may be perceived there — appear to 
us under.quite a different form. Must we, then, return to 
the theory of a cloven disc or to that of a galactic ring ? 
Certainly not. Proctor has, without doubt, been right in 
giving up these premisses : that the theory of a stellar 
stratum in form could not be defended in these days, and 
that the phenomenon of the Galaxy is due to a distribution 
of the stars of a much more complicated character than 
could be produced by a ring, however irregular. 

Without entering into details which would take too 
much space here, I hope to give a summary of what has 
led up to the result that the most modern researches (after 
Proctor) have established with sufficient certainty. 

The visible universe, stars and nebulm (with the excep- 
tion of nebuliE properly so called/, is extended in a flat 
layer irregularly condensed. The stars differ extremely, 
not only as regards their volume, but also as regards the 

* Drawings of Heis, Houzeau, Davis and Thome (G-ouId), Boed- 
dicker, Easton, and otfier.-* ; photographs of Barnard, Wolf, ^nd 
Russell. Tlie readers of Knowlkd&e hare often had prints of these 
admirable photographs of the Milky Way. 



14. 



KNOWLEDGE 



[Januaey 1, 1898. 



intrinsic brightnesa of their surface. The mode of distribu- 
tion of the stars is not the same in different regions of the 
stellar layer, but the distribution of the great stars is not 
independent of that of the small ones. The stars of the 
spectral type — named " solar type "—are condensed about 
a point which, in comparison with the extent of the whole 
system, is not very far removed from the sun/' 

Proctor looked upon the Milky Way as " the condensed 
part of a spiral of simill stars " amidst the sidereal system. 
This theory is incompatible with the results recently 
obtained, in particular with those of Kapteyn and of my 
own concerning the distribution of stars of differing 
magnitudes in some parts of the Milky Way (see Know- 
ledge, August, 1895). In the galactic belt the large and 
small stars are moat certainly intermingled. 

But modern researches have not yet touched upon a new 
theory of the Milky Way — a theory which can at least 
explain, as Proctor wished to do, the bolder and more 
striking features of the Milky Way. Giovanni Celoria 
alone, at the Observatory of Brera in Milan, has ventured 
as far as could be at his time (187H). From his pains- 
taking and most interesting researches! he did not evolve 
a complete theory, but the comparison of his star-counts 
with the gauges of William Herschel and the " Bonn 
Durchmusterung" led Celoria to conclude that the "MOky 
Way ia composed of two branches, two distinct rings, of 
uninterrupted circumference. One of these rings is re- 
presented by the continuous feature of the ]Milky Way, 
crossing the sky in Monoceros, Auriga, Sagitta, and Aquila ; 
the other begins in the brilliant stars of Orion, passes 
through the Hyades, the Pleiades, Perseus, Cygnus, and 
ends in Ophiuchus. The two rings cross each other, 
and are perhaps confounded in one system in the constel- 
lation of Cassiopeia ; and separating, one part passing 
through Cygnus and the other through Perseus, they 
make an angle of about nineteen degrees." 

I do not need to say that the second ring of Celoria, 
crossing Orion and Ophiuchus, is identical with the belt 
of bright stars of Sir John Herschel and of Gould ; but, 
in the course of his research, Celoria found that there 
existed in this region a veritable galactic branch, with 
many stars relatively brilliant although telescopic, and 
few stars of the inferior order of brightness — at least in 
the sections studied by the Italian astronomer. 

Although there is doubtless much truth in the conclu- 
sions drawn from this great work, it is impossible, in the 
actual state of our knowledge of the composition of the 
Milky Way, to accept the " due anelli distinti, ue mai 
iuterrotti nel loro corso " of Celoria. Even if the two rings 
are tenable, it must be recognized that there are lacunas, 
interruptions, and, in a word, manifest compUcationa. 

If one would rest on the solid ground of fact, one cannot 
go beyond this conclusion — at least as regards the great 
problem of the structure of the heavens ; great irregulari- 
ties of detail, traces of at least partial regularity in the 
principal features. But I hope in another paper to venture 
a little further in this tempting region, without, however, 
quitting a firm hold of observed facts. 

* For furtlier particulars, see among others— G-ould, Vranometria 
Argentina, 1879; Scbiaparelli, Piibbl. del R. Osservatorio di Brera, 
XXXIV. ; Celoria. idein. XIII. ; Plassmann, Jahre.ilericht d. 
Westfahlia, Pr. Vereinx, 1886; Eistenpart, Ber. Sternw. in Karlsruhe. 
1892 ; Kapteyn, Versl. Aiademie v. Wet. Amsterdam, 1892 and 1893 ; 
Gore, " Visible Universe," ete. ; Ranvard, Knowibdoe, June, Nor- 
ember, 1894; Maunder, Knowledge, February, November, 1895, 
February, 189G; Easton. Aslron. Xachr.. 3270. Compare aUo 
Knowledge, October, December, 1891; May, 1892; April, 1893; 
October, 189-1; January, August, 1895. 

t Giovanni Celoria. " Sopra alcuni scandagei del eielo et sulla 
distribuziohe geuerale delle stelle nello spazio." Pubhl del S 
Osserr. di Brera, XIII.,Milano, 1878. 



BRim-tt 



'^ 




ORNITHOLOGICAC*^ .=^ 



Conducted by Habbt F. Witheeby, f.z.s., m.b.o.u. 

A New British Guij:*. — The Mediterranean Herring 
Gull (Larus rafhinnans ), — The past autumn has been 
exceedingly unproductive of the rare migranta which 
usually viait the east coast ; it is therefore especially 
gratifying to be able to rescue from oblivion a rare bird 
which has been unrecorded since the month of Novem- 
ber, 1880. Mr. Cole, the well-known bird preserver, of 
Norwich, recently called my attention to a Gull which was 
shot on Breydon Water, near Yarmouth, on the above 
date, by the noted gunner -John Thomas, and sent to him. 
The late Mr. Henry Stevenson examined it in the flesh 
and stated his opinion that it waa an example of 
the Mediterranean Yellow-legged Herring Gull (Larus 
ciu-hinnans) ; but, somehow, it passed out of notice till Mr. 
Cole called my attention to it recently, when a careful 
examination of the bird convinced me that Mr. Stevenson's 
opinion was correct. This has since been confirmed by Mr. 
Howard Saunders. The bird is a male by dissection, and 
differs from the common Herring Gull in having the mantle 
darker, the base ring round the eye deep orange-red, and 
the legs lemon-yeUow. The resemblance to the common 
Herring GuU is, however, so great that it might easily be 
overlooked. The month of November aeems to be a very 
unlikely one for the occurrence of this southern species on 
our coast, but I find that the weather at that time was 
exceptionally mild and pleasant. It is also remarkable 
that in the following month another Mediterranean species, 
Larus melnnorephalus, was killed in the same locality. — 
Thomas Southwell, Norwich. 

Ferki'Gi.nots Duck [FuJifjula nyroca) ix West Meath. — 
Mrs. Battersby, of Cromlyn, informs me that a bird of 
this species was shot by Colonel J. K. Malone, at Barons- 
town, Bahnacarghy, West Meath, on January 17th, 1897. 
The bird was stuffed by Mr. E. WiUiams, Dame Street, 
Dublin, who informs me that it was a mature female. 
Thia apecimen does not seem to have been recorded before, 
and, as the species haa only been identified four or five 
times in Ireland, the occurrence is worthy of record, 
although the bird was shot a year ago. — H. F. W. 

A Norfolk Great Bustard. — Through the kindness of 
Prof. Newton I was enabled a few months ago to purchase 
a remarkably fine male example of the old local race of 
this magnificent bird. The result of my inquiries amply 
established its history, which is briefly as follows : — The 
bird was shot on Swaffham Heath about the year 1830 by 
a gentleman named Glasae, who then reaided at "\'ere 
Lodge, Eaynham, near Fakenham, Norfolk. It remained 
in his possession and in that of his daughter until, on 
the death of the latter at Bournemouth, early in the 
present year, it was sold by auction with the rest of her 
effects, and ia now in the collection of Mr. Connop, of 
Kollesby Hall, Great Yarmouth. This superb old male 



January 1, 1898.] 



KNOWLEDGE 



15 



in magnificent plumage, is even larger than the grand 
male in the beautiful group of seven of these birds in 
the Norwich Castle Museum ; and from the date of its 
death is not unlikely to have been the last male of the 
Swaffham drove, the females of which were not finally 
exterminated until the year 1838, when the last of the 
Norfolk-bred Bustards was killed. — Thomas Soi-thwell, 
Norwich. 

Waxwincs [Am pel i.^ tjarnihis) at Scari!0R0u<;h. — There 
are quite a lot of Waxwings at the present time (November 
4th, 1897) in this locality, upwards of half a dozen having 
been shot and sent to me for preservation. The birds which 
have been captured were found feeding on the berries of 
the mountain ash and alder, and were so tame as to allow 
their executioners to walk beneath the bush whilst they 
sat on the top of it quite undisturbed. — J. Morlev, King 
Street, Scarborough. 

Variety of the Common Giillemot at SiARnoRorciii. — 
A beautiful variety of the common tluillemot was caught 
on December 4th, 1897, in Scarborough Harbour. Its 
head and entire under parts are white, whilst its back 
and wings are of a whitey-brown colour, and its bill, legs, 
and feet yellowish white. A bird of this description is 
extremely rare ; a similar one was obtained a few years ago 
at Filey. The writer has visited Speeton Cliffs for many 
years during the breeding season, and amongst the 
hundreds of thousands of birds that annually resort there 
for breeding purposes, has seen but one creamy coloured 
Ciuillemot. — -J. Morley, King Street, Scarborough. 

House Sparrows and Pigeons, — That Span-ows should 
singly pursue Pigeons — white birds for preference — and 
snatch feathers from the breast and sides, is, I imagine, 
no news to the majority of your readers, though I have 
more than once met with doubt when alluding to the 
practice. Never before, however, have I observed this 
robbery in mid-air before March ; and it may seem to you 
a sufficiently interesting sign of the abnormal state of 
things this year — though to-day is cold enough — that I 
have this morning seen four feathers taken in this way 
from the white Pigeons next door. This haste for warm 
lining for the nest points, without doubt, to very forward 
domestic arrangements. — F. G. Aflalo, Bournemouth, 
December 4th, 1897. 

[Sparrows commonly take feathers to their roosting 
places during the winter. The fact of their carrying 
feathers about at this time of year does not, therefore, 
necessarily point to early nesting. — H. F. W.] 

Occurrence ok a Colony or Jackdaws having Domed 
Nests. — My boys having told me that for several years 
they had found in the neighbourhood of Moddershall, 
Stafi'ordshire, -Jackdaws with nests like Magpies, on the 
14th May Dr. McAldowie (author of " The Birds of Stafford- 
shire ") and I went to verify this strange occurrence. On 
our arrival at the spot indicated to us — a group of Scotch 
firs on a bank rising from a large pool — we found five large 
nests, and saw flying roimd overhead four old Jackdaws. 
On a later day, accompanied by one of my sons, I paid 
another visit to the colony. One nest was placed at a 
height of fifty-eight feet, in the highest fork of a tree. 
The nest was a very bulky one, two and a half feet in 
diameter and of a like depth, constructed of sticks ; the 
nest cavity, which was ten inches across, being filled with 
cow hair and wool, of which there was a large quantity, 
and the whole covered and protected by a strong dome of 
thorny sticks, which a hedge at the side of the plantation 
had no doubt supplied, it having been recently cut and 
the cuttings left on the ground. There was one entrance at 
the side of the dome. The nest was empty, and from the 
absence of dirt and castings was evidently one of this year. 



Two other nests were placed in similar positions in other 
trees ; one contained four young birds about a fortnight old, 
and the other was an old one. We found some egg shells 
under another tree, but did not climb it. I have made 
inquiries, but cannot hear of these trees ever having been 
occupied by Rooks ; and the absence of earth and clay, with 
which Magpies invariably line their nests, makes it im- 
probable that these birds were the builders. I am there- 
fore compelled to believe that the Jackdaws built these 
nests. There are two other colonies of Jackdaws in the 
neighbourhood, both in sandstone cliffs, and a mile or so 
from the colony I have described. I shall be extremely 
obliged if any of the readers of Knowxedue who may 
have met with a similar occuiTence will describe it. — W. 
Wells Bladen, Stone, Staffs. 

[It seems difficult to prove that these nests were not 
old Magpies' nests relined and restored by the Jackdaws. 
The earth and clay of the Magpies' nests would probably 
wash away in the course of time. It would be very 
interesting if, during the coming spring, Mr. Bladen should 
be able to incontestably prove that these Jackdaws do 
build domed nests.— H. F. W.] 

yofes OH an Expedition to Sockall. By R. Llojd Pracger, B.E. 
(Irish yaturaUst, December, 1897, pp. 309 to 323.)— This is a brief 
diarj of ten days spent in twice visiting the oceanic islet of Rockall, 
and forms the "day-by-day experiences of the party sent out in June, 
1896, by the Royal Irish Academy, to investigate the natural history 
of this little knowB and inaccessible rock and of its vicinity." Ln- 
fortunatcly the expedition was unsuccessful in attaining its main 
object — that of landing upon the rock. 

All contrihutioiis to the column, either in the icny of notes 
or photoi/raphs, should be forwarded to Haery F. Witherby, 
at 1, Eliot Place, Blackhealh, Kent. 

Note. — The first issue of Knowleiigk containing British Ornitho- 
logical Nott'i was that for October, 1S97. 

Mr. Walter Siche, the traveller and florist, has returned 
from an expedition to the Cilician and Cappadocian 
Taurus with a large number of alpine plants, and ten 
thousand examples of various species of the asphodel family, 
with varieties of fritillary, galanthus, colchicum, iris, and 
many other plants. Mr. Siche has been the means of 
introducing many new flowers to the domain of English 
horticulture. 



Lieutenant Peary, of the United States Navy, in his 
recent address before the Koyal Geographical Society, said 
that to-day Greenland had no interior — it was simply a 
great white snow shield. On that frozen surface the 
traveller sees but three things — an infinite expanse of 
snow, an infinite expanse of sky, and the stars. One thfng 
of interest to glacialists which he mentioned was the 
transportation of snow by the wind, which was almost 
always blowing there. Referring to his location of the 
famous iron mountains of Sir John Ross with their 
nuggets of iron, he intimated that the Eskimo legend in 
regard to these nuggets was that they were originally an 
Eskimo woman and her dog, which were thrown out of 
high heaven and landed in that inhospitable region. A 
woman six thousand pounds in weight was the source 
from which the Eskimo obtained their iron supply for 
generations ! 



Sir John Lubbock, lately lecturing on " Ants," said that 
the lives of these creatures were much longer than is 
generally supposed. He had kept many for several years, 
two queens having reached the age of fifteen years, and 



16 



KNOWLEDGE 



[Januaby 1, 1898. 



these were by far the oldest insects on record. Several 
species kept aphides which they milked like cows ; and he 
had found that in the autumn they collected the eggs o( 
the aphides and kept them all through the winter, although 
they were of no use, and the young aphides hatched from 
them gave none of the sugary fluid till the following 
May or June, so that the ants showed more thrift and 
forethought than many human beings. Their instincts, 
though so wonderful, were very limited ; and yet, when the 
ants were watched building their nest, feeding their young, 
tending their domestic animals, and, in some cases, their 
slaves, it was diilicult to believe that they were unconscious 
automata. . , , 

We are pleased to observe that a scheme is shortly 
to be submitted to Parliament involving the expenditure 
of upwards of three millions for the better housing of 
the national collection of art treasures in and about South 
Kensington Museum. The Bill for this purpose is to 
be brought before Parliament next Session, and there will 
shortly commence to be built a series of exhibition rooms 
and galleries, to concentrate in one area the many works 
of art and objects of interest now scattered in various 
extempore structures. It is to be hoped that among the 
innovations there will be a replacement of those wooden 
huts— called by courtesy an observatory, but bearing a 
much closer resemblance to a hen farm — by something 
more in keeping with the long purse of a Government with 
suchre sources as ours. 



A great undertaking, namely, the measurement of a 
degree of latitude in the Polar regions, leading to a more 
exact knowledge of the form of the earth, appears to 
be on the eve of accomplishment. The solution of this 
question has long been the chief aim of Swedish Polar 
exploration, and Prof. E. .Jaderin has now proposed to 
the Government for a preliminary expedition to be sent 
to Spitzbergen next summer, and that Russia should be 
invited to co-operate in the final measurement of a degree 
in 1899 and 1900. The task of the preliminary expedi- 
tion—which it is intended should start in May and return 
in September— would be to complete the investigations 
already made as to the facilities for the necessary triangu- 
lation, to reach the summits of hitherto unchmbed moun- 
tains, to set up signal posts, and so on. 

Dr. Campbell Morfit died last month at South Hamp- 
stead. An American by birth, he had for many years 
past been a London resident. He was the author of 
" Chemical and Pharmaceutical Manipulation," " Arts of 
Tanning and Currying," "Oleic Soaps," and, with Dr. 
James C. Booth, was joint editor of the American " Ency- 
clopsediaof Chemistry "; and in the industrial utilization of 
waste products, as well as the chemistry of food substances, 
his researches have been of the utmost service to the 
general public. 

The November Number of the "Archives of the 
Roentgen Ray," which is now the organ of the Roentgen 
Society of London, contains an excellent report of 
the presidential address delivered by Prof. Silvanus 
Thompson, i-.r.-;., to the Roentgen Society at St. Martin's 
Town Hall, on November 5th, 1897. The number also 
contains five large skiagraphic plates and other interesting 
matter. A supplement entitled " Radiography in Marine 
Zoology," by R. Norris Wolfeuden, m.d., is added. This 
supplement treats of the Echinodermata, and is illustrated 
with thirty-six excellent skiagraphs and photographs. 

* See avticle, " Measurement of the Earth," Enowledge Jime 
1897, p. 148. ' ' 



lUttttxs. 



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

• THK LIFIvHISTORIES OF THK BRITISH MARINE 

FOOD-FISHES." 

To tlie Editors of Knowledge. 

SiKs, — Kindly allow me a few words to conclude the 
correspondence on this subject. 1 have not denied, as 
your reviewer states, that " the work of St. Andrews is put 
more prominently forward than work done elsewhere," 
in our book. Such is, no doubt, the case ; and it is, as he 
remarks, " not unnatural," considering that by far the 
greater proportion of British "fishery" work has been 
done there, or in direct connection therewith. This is a 
different matter from "ignoring" the work done elsewhere 
Your reviewer's statement that " Mr. Cunningham led 
the way " in the subject of the growth-rate of fishes has 
no foundation of truth. This worker published his first 
paper upon the subject in 1890, and at periods varying 
from five to twelve years prior to this the works of Dr. 
Mcintosh, Captain Dannevig, and Dr. Meyer had appeared. 
Without further instance, your readers may be reminded 
that the two latter still stand as the best known authorities 
upon the growth-rate of the cod and herring respectively. 
" The credit of the discovery of the hermaphroditism oi 
Mtj.iiiw" is not "given to Dr. Nansen." A passin;,' reference 
to i>r. Nansen's work is mentioned in a quoU'ti'in from 
another paper, in connection with which the reasons for 
its selection were given. 

The life-history of Mi/.i-ine did not fall within the scope 
of our work, or, of course, the labours of W. Miiiler, 
Cunningham, Weber, etc., would have been referred to. 

With regard to Xaturc, my remark was to the effect that 
Dr. Lankester was allowed, under pretext of reviewing our 
work, to make certain false statements outside the pale of 
legitimate criticism, judged by the widest standard ; and 
that the editor, in the opinion of a great many of his 
readers, showed a partiality in not allowing a contradiction. 
Your reviewer considers my remarks " hardly in good 
taste" because Mr. Cunningham was similarly denied on a 
prior occasion. Surely this fact, which could not have 
been known except to Mr. Cunningham himself and his 
most intimate friends, merely corroborates my' remark that 
your contemporary has been " not unknown " for such 
unfair treatment of authors. Mr. Cunningham has reason, 
judging from your reviewer's statement, to complain of his 
treatment, and still more to complain of the invidious posi- 
tion in which your re\iewer has attempted to place his work. 
In conclusion, 1 must now leave it with your readers to 
judge for themselves how far your reviewer has established 
his position that we have ignored the work of others in 
our labours. 

The University, St. Andrews. A. T. Masterman. 

[In my notice of " British Marine Food Fishes," I 
remarked : " Between the marine biologists of the North 
and South there is something of a spirit of rivalry, the 
result being that each school is inclined to ignore, more or 
less, the work of the other — or, at any rate, not overburden 
it with praise." No impartial critic, familiar with the 
facts, could deny that every word of this sentence is true. 
It will be noticed that I did wt assert that Dr. Mcintosh 
and Mr. Masterman had "ignored the work of others in 
their labours " : but surely the first paragraph of Mr. 
Masterman's letter justifies my position. 

Mr. ]\Iasterman (p. 291) asked for an instance of " Mr. 
Cunningham's work which had not been alluded to and 



January 1, 1898.] 



KNOWLEDGE. 



17 



freely acknowledged." I gave him the case of fhe work on 
the growth of fishes, referred to in a cursory manner which 
deprives it of any importance. Of course, Mr. Masterman 
may be permitted to have an opinion of his own as to 
what work is important, but marine biologists are also at 
liberty to challenge it. 

With regard to the hermaphroditism of ^fl|.l•ille, the 
quotation is from a paper by Mr. Masterman himaelf, and 
the words used are ; " We may cite Nansen's observation 
of the protandric hermaphrodite cDndition of Mi/xine." 
This certainly gives the idea that the hermaphroditism 
was discovered by Dr. Nansen. 

As to Nature, Mr. Masterman distinctly ascribed "par- 
tiality" to the editor in tlie matter of the review of 
his book. He knows that Mr. Cunnmgham's work was 
treated in exactly the same way that the work of Dr. 
Mcintosh atfd himself was treated, and yet he has not the 
good grace to withdraw his charge of partiality. I cannot 
say that Mr. Canningham sent a reply to the criticism of 
his own work, but I know that no reply was published in 
Natui-f, any more than was 'Sir. Masterman's reply to 
Prof. Lankester's review. It is a pity that there are 
authors like Mr. Masterman ever ready to resent fair 
criticism and impugn editorial actions. — The Reviewer.] 



TESXINO- MULTIPLICATION AND DIVISION. 
To the Editors of Knowledge. 

SiKs, — The properties of " the mystic numbsr three," 
and its square 0, referred to by your correspondents on 
page 292 of your migazine, bring 0113 back to the 
earliest recollec lions of one's school days, when the multi- 
plication sums were tested by "casting out the nines," as 
it was then called. The property that the sum of the 
digits of any integer, divided by .9, gives the same 
remainder as if the number itself were divided by 9, is a 
natural consequence of our decimil notation. Had the 
notation been duodecimal, 11 would have possessed the 
same property; and, even in the decimal notation, 11 
may be used with almost equal ease, and is a safer test. 
Beginning with the units, add the alternate figures, and, 
carryiug to the tens, add the other alternate figures ; then 
add what is over to the units of the sum. If the number 
thus obtained be divided by 11, the remainder is the 
same as if the whole number were divided by 11. 
This can be easily shown from the obvious fact that every 
even number of nines is divisible by 11. These pro- 
perties are well known, and hardly need illustration. 
They are mentioned as introductory to what follows. 

Some years since, I had to do with the multiplication 
and division of very large numbers, consisting of sixty 
figures and upwards. Finding that neither '-) nor 11 was 
a sufficiently reliable test, I was led to seek for something 
safer. The numbers, for distinctness, were arranged in 
periods of five figures each, beginning of course at the 
right. My test was to be adapted to tliis arrangement, 
and I soon found that 11111, consequently 99999, is 
divisible by 41 ; therefore 99999 99999, etc. It follows 
that if the sum of the periods, taken as separate numbers 
and carrying what is over to the units' place, be divided by 
41, the remainder is the same as if the whole number were 
divided by 41. 

The division by 41 may be abridged thus : — 
Let the sum of the periods, found 

as above, be 37529 

Subtract the largest multiple of 

mil contained therein ... 33333 



41)4196 remainder 14, 



showing that, if the whole number were divided by 41, the 
remainder would be 14. 

Years afterwards I was requested by the late Prof. 
Cayley to verify some results, involving also very large 
numbers, but arranged in periods of three figures each. 
To this also it was judged expedient to use a test specially 
adapted to the arrangement. I saw that 111, therefore 
999, is divisible by 37 ; and consequently that if the sum of 
the periods of three figures, taken as above, be divided by 
37, the remainder is the same as if the whole number were 
divided by 37. 

Take, for example, any numbar at random, say — 
45 286 507 613 941 
The sum of the periods is 2 392 

and, adding 2, the unit of the second period in the sum, to 
the first period, we obtain finally 394 

Subtract the largest multiple of 111 therein 333 

The number thus obtained 61 divided 

by 37, leaves the same remainder, 24, as if the whole 
number were divided by 37. 

A. Graham. 
Cambridge Observatory, 

14th December, 1897. 



ARTIFICIAL SUNSPOTS. 
To the Editors of Knowledge. 

Sirs,— With regard to Mr. East's experiments and your 
remarks in the Dacember Number of Knowledge, is it 
possible that in the sun's surface we have anything similar"? 
—that is, are the rice grains really the only partial con- 
solidated matter that we see ?— all the interior of the sun 
being in a gaseous state, under such conditions of extreme 
heat and pressure as to make chemical combination and 
luminosity impossible. I should like to see some remarks 
in your journal on this head. It seems to me one of 
impossibility ; the photosphere would then be the very 
first stages of a crust formation on the sun. 

December lOih, 1897. Thos. .1. Haddy. 



BARE BIRDS. 
To the Editors of Knowledge. 

Sirs, — Your issue for December contains an account of 
the shooting of four rare birds. Most probably each of 
these rare birds had mates and would have continued the 
race if let alons, but the collector comes with his gun and 
endeavours to make the rare bird an extinct bird. Of 
course, his specimen would become more valuable if this 
species of bird became extinct in this country, while if he 
allowed the bird to escape he would have no specimen at 
all. But is this a suflicient reason for shooting a bird that 
is doing no harm and is not intended to be eaten, and 
whose only crime is that very few Uke it are to be found in 
this country ? Our object should be to preserve — not to 
destroy — such rare specimens. This would be admitted if 
they were domestic animals. It is only when an animal 
is wild that he is shot because there are few Uke him. If 
the shooting goes on there will soon be none. 

It is time that we had a society for the preservation of 
rare animals and birds — unless, of course, they are mis- 
chievous like the wolf, which has now died out in the 
British Islands. 

Every zoologist will admit that utility is not the only 
thing to be looked to as regards the preservation or 
destruction of a race of animals; and, if there is no reason 



18 



KNOWLEDGE. 



[January 1, 1898. 



for the extirpation of any peculiar species, why should we 
seek to extirpate them merely because they appear to be 
dying out of their own accord ? I would rather preserve 
them as long as possible. 

The dying out of a race of animals, when natural, may 
often indicate a gradual change of climate or other physical 
conditions, the history of which it will be desirable to 
trace hereafter. The arrival of a new race may afford 
similar indications to the student of science. But if we 
ruthlessly shoot down every member of a race that is dying 
out and every now arrival on our shores, landmarks of this 
description will be lost. The "footprints on the sands of 
time " wear out soon enough without intentional oblitera- 
tion. W. II. S. MONCK. 

[The killing of rare birds has of late formed the subject 
of innumerable letters in the daily press. These letters are 
invariably written by persons not suliiciently acquainted 
with the details of the subject to form an accurate opinion 
as to whether the killing of any particular bird is to the 
advantage or disadvantage of the study of British birds. 
By this we mean that unless certain birds are killed 
ornithology will not advance. Glance, for instance, at the 
second part of Mr. Howard Saunders's manual (just pub- 
lished). There are at least six birds out of the twenty- 
four there described which would never have been known 
to have visited the British Islands had they not been shot. 

With regard to the birds mentioned by Mr. Monck, these 
were all stragglers, and we can confidently say that none of 
them would ever have bred in Great Britain had they been 
allowed to live, and certainly three of them would never 
have been identified unless they bad been shot. We do 
not wish our readers to infer from the foregoing remarks 
that we uphold the killing of every rare bird. Far from 
it. We consider it an act of ignorant greed to destroy in 
Great Britain a bird such as a Golden Eagle or Osprey, 
which were formerly fairly plentiful as breeding species, 
but have now become very rare. We would remind Mr. 
Monck that the Society for the Protection of Birds, which 
has often been referred to in Knowledge, has been estab- 
lished some years, and has done and is doing very good 
work in the prevention of that very ignorant destruction 
to which Mr. Monck so properly objects. — Eds.] 



MOVEMENT IX SP.VCK. 
To the Editors of Knowledge. 

Sirs, — I saw it stated the other day that one of our 
astronomers had made a calculation that the rate of 
movement of our sun in space was twelve miles a second. 

This idea of "movement in space" is to me incom- 
prehensible. What we call " movement " is a relative 
state of matter, and can only be measured against some- 
thing " at rest." For instance, we call an object fixed or 
stationary on the earth, when really it participates in the 
earth's motion ; so it is quite possible that a fly on the 
woodwork of a railway carriage may consider itself " at 
rest " when it pauses in its walk, although the train is 
travelling at its usual speed. 

As it would appear from our limited knowledge of the 
universe that a state of absolute rest is impossible, it 
would be interesting to know how this movement of the 
sun can be measured with anything approaching accuracy. 

If you consider this a suitable subject to appear in your 
very interesting magazine, you would much oblige, 

Ignoramus. 

["Ignoramus" is quite right in supposing that motion in 
space can only be measured by taking some origin which 
we suppose fixed. In deducing the solar motion we 



assume that the group of stars which we employ for the 
purpose have, as a whole, no tendency to drift in any 
direction^or, in other words, that their centre of mean 
position is at rest. This centre of mean position is thus 
the fixed origin to which the solar motion is referred. 
The whole system of stars under discussion, including 
our sun, may have a common drift in some direction, but 
this we are unable to determine.] 

Notices of Boolts. 

With y'ature ami a (amern. By Richard Kearton, f.z.s. 
Illustrated from Photographs by Cherry Kearton. (Cassell.) 
21s. Perhaps we expected too much of Mr. Kearton, 
judging from reports which reached us before the publication . 
of his book. However that may be, we are disappointed. 
There are many good things in the book, but it is our candid 
opinion that the author has been too hasty in putting his 
work before the public, for it bears unmistakable signs 
of " padding." A number of tlie photographs are not 
of sutlicient interest for publication, while to others a 
great deal too much space has been given, making the 
book large, expensive, and annoying to the reader. The 
most glaring examples of " padding " are two full-page 
illustrations of a rabbit burrow closed and a rabbit burrow 
open (pages 178 and 179), a common enough sight to 
everyone. If the photographs had been " pictures " we 
should, perhaps, have excused the author, since his book 
is mainly a " picture book " ; but they are by no means 
pictures, and are made additionally hideous by a large 
bottle in the foreground. The letterpress also is by no 
means free from " padding." A number of the facts- — 
some of them here set down as extraordinary— have been 
published scores of times before. It is well known that 
the song thrush sings occasionally on fine nights : yet the 
author, who has had some experience, was " astonished to 
hear a thrush commence to sing " one moonlight night, 
and considers that in this fact he has " unmistakable 




proof" that "birds may, upon occasion, mistake the 
rising of the moon for the coming of another day." The 
author gives a detailed account of an old shooter and his 
favourite " setter " bitch, and on page 161 he gives a 



January 1, 1898. 



KNOWLEDGE 



19 



photograph of the two ; but the "setter" is an unmistakable 
pointer. Having said so much of what we consider to 
be bad judgment and error, we gladly pass on to the good 
points in the book. These are chiefly to be found in the 
photographs, a great number of which are exceedingly fine. 
We would especially draw attention to the following : — 
Barn owl, photographed by flashlight (page 24B), kingfisher 
(page H57), cormorants and guillemots (page 251), common 
gull's nest (page 269) ; and to those which we have been 
able, by courtesy of the publisher, to here reproduce. Mr. 
Cherry Kearton, who has taken the photographs for his 
brother's book, has had many perilous 
adventures, as all who climb cliffs — and 
especially those who carry a camera with 
them — must ; but we cannot help thinking 
that Mr. Kearton has often run into un- 
necessary dangers. Many of the things he 
has photographed in difficult places could 
have been found in more accessible situations. 
We recommend the book with the (jualification 
that if the author has not made " much ado 
about nothing," he has certainly made too 
much of not a very great deal. 

OniKiiieiitdl lk'si(jn fur ll'oren l^'ahrics. By 
C. Stephenson and F. Suddards. (Methuen.) 
Illustrated. 7s. 6d. We are not by any 
means convinced that the authors of this 
handsome-looking book have succeeded in 
their laudable desire to " bring the necessary 
knowledge within a narrower focus, and 
thereby make it more easily accessible." In 
attempts like this to find the path of least 
resistance to a useful knowledge of a science 
or an art, there is always a danger of re 
tarding progress by, in a manner, increasing 
friction — making the pathway too constricted 
for one to get through with comfort. For 
example, although a knowledge of elementary 
geometry is assumed, a single plate is given 
showing the construction of the most simple, 
and at the same time useful, figures, and 
then in a few pages their application to the 
design of woven fabrics is dispensed with. 
The authors, indeed, exhibit a clear insight 
as to the way in which such figures are 
utilized in the designer's office ; but a beginner 
would be all at sea in practice if only equipped 
with such knowledge as is here so over con- 
densed as to be nearly, if not quite, indi- 
gestible. Coming to the main part of the 
work, however, we find a difl'erent state of 
affairs. Dealing with the laws of com- 
position, plant forms in textile designs, 
limitations imposed, drop-pattern, repeats, 
and so on, as well as in the arrangement 
of the warp-threads and their sequence 
in rising and falling in order to attain 
any given pattern, all is clear, and in the 
highest degree commendable. The book 
way handsome, and the illustrations are 
quality. 

TIk Rise nt Piinocrncy. By -J. Holland Eose, m.a. The 
Victorian Era Series. (Blackie i- Sou.) 2s. 6d. This is a 
wholly inadequate treatment of a great subject, due in a 
large measure to the laudable desire of the author to 
compress a vast amount of historical detail into a small 
compass. The result is a more or less disjointed catalogue 
of names and incidents, often incomplete, and always 
lifeless. Admittedly circumscribed in the space at his 



disposal, Mr. liose has persistently stood in his own way, 
and filled valuable space by recounting his own inter- 
pretation of the facts, so that his reader is often unable to 
appreciate the picture by reason of the obtrusive nature of 
the showman. However interesting the author's opinions 
may be to Mr. Rose, he should remember they are of no 
value to his reader. Some haste, too, is apparent in the 
text, where we find Sir Francis Bm-dett, the famous 
member for Westminster, figures as Sir Thomas Burdett, 
and Richard Carlile as Carlisle ; while the alleged " toning 
down " of -John Stuart MiU is, of course, an entire mis- 




Guillemots on Cliff. (From " With Nature and a Cam 



13 m every 
of first-rate 



apprehension of the facts. Then we do not like to find 
such phrases as the " immense vogue " of Darwin, or the 
" viewy schemes " of Owen, in a book which promised in 
the preface to be " scholarly." The index, too, is hasty, 
incomplete, and lacking in method. Yet, notwithstanding 
these defects, Mr. Rose's little book will be found to be an 
interesting sketch of the growth and expansion of repre- 
sentative institutions in England, as well as of the patient 
doggedness and prescience of our countrymen. But it 
leaves the task yet unfulfilled of writing the history of the 
rise of democracy. 



20 



KNOWLEDGE 



[Jantjaby 1, 1898. 



An Introduction to Geology. By Wm. B. Scott. (Mac- 
millan.) lUuatrated. Ss. net. New strata of books, so 
to speak, are being continually superposed on pre-existing 
books of the same kind, and it too frequently happens that 
they contain no fossils, as it were, to invest them with 
special characteristics sufficient to differentiate them from 
their predecessors. In a sense, Prof. Scott's work is of 
this kind — that is to say, the book is not of any particular 
value to English students, but rather a class-book for 
American students of geology. The principles of the 
science are elucidated in a manner closely corresponding 
with our own standard works on the same subject. To 
those, however, who have advanced beyond the confines 
of an acquaLatance with first principles, and are prepared 
for fresh fields and pastures new, we may say there is 
here much that is worthy of careful study — matter to fill 
many a gap, confirm or accentuate doubtful points, and, 
above all, a panorama of familiar phenomena in a new and 
attractive dress, which will lend a more extensive, more 
diversified, and more persuasive view to the mental eye. 

Jdhn Hunter : Man of Scienre and Suryenn. By Stephen 
Paget. (Unwin.) Portrait. 3s. 6d. Among the greatest 
men that England has produced must be reckoned those 
who have built up the science of medicine in its broadest 
sense, and among savants of this kind Hunter was head 
and shoulders above his contemporaries — one of the master 
builders of the Temple of Hygiea. The whole secret of 
his extraordinary achievements in life can be expressed 
Ln a few words: "Don't think — try; be patient — be 
accurate." A great deal, it is true, may be learnt by 
thinking ; but when experimental facts are brought to 
bear upon a certain theory, more exact conclusions can 
be deduced than by mere speculative opinion without the 
foundation stones of exact observation. As a boy, Hunter 
was an observer of nature, and did not care much for his 
school books ; and when he came to London to work 
with his brother William, he studied hard for three years, 
spending his time mainly in the dissecting rooms night 
and day. Thus far, Darwin and Hunter, in so many ways 
alike, went both of them along the same high road ; here 
the road divides at a narrow angle. Hunter went forward 
from human anatomy to all anatomy and physiology, and 
from these to medicine and surgery, and from all of them 
together to a profound study of life, alike Ln health and 
disease, in all structures, at all stages. To the medical 
student of the present day the correspondence here given 
between Hunter and his famous pupil, Jenner, must present 
a strange picture. Our museums now supply all the 
requisites for study, but in Hunter's time every student 
had to cater for himself : find specimens for dissection 
where he could ; get his chemical knowledge from one 
source, anatomy from another, and so on ; all outside the 
hospitals, which were not organized for complete instruc- 
tion. The book is one of a series — " Masters of Medi- 
cine " — and will include among others : Harvey, Jenner, 
Simpson, Helmholtz, Stokes, Bernard, Brodie, and 
Sydenham. Provided subsequent volumes are of equal 
merit with this one, the series will form a most delightful 
record of the development of the healing art. 

Recent and Cominij Eclipses. By Sir Norman Lockyer. 
(Macmillan.) Illustrated. 6s. net. By this time Sir 
Norman Lockyer may be regarded as a veteran eclipser. 
During the last quarter of a century he has captained 
many expeditions, and anything he has to say on eclipses 
will be sure to command the attention of all interested in 
such phenomena. In describing what he saw in 1871 the 
author gives us some idea of the imposing grandeur of an 
eclipse in these words : " There, in the leaden-coloured, 
utterly cloudless sky, shone out the eclipsed sun — a worthy 



sight for gods and men. There, rigid in the heavens, was 
what struck everybody as a decoration— one that emperors 
might fight for — a thousand times more brilliant even than 
the Star of India, where we then were ; a picture of 
surpassing loveliness, and giving one the idea of serenity 
among all that was going on below ; shining with a sheen 
of silver essence ; built up of rays almost symmetrically 
arranged round a bright ring above and below, with a 
marked absence of them right and left, the rays being 
composed of sharp radial lines, separated by furrows of 
markedly less brilliancy." Although the author, according 
to the title page, purports to give in his book notes on 
the eclipses of 1893, 189G, and 1898, considerable space is 
taken up with the subject of eclipses generally. Seeing 
that the sun itself is essentially a star, we quite expected 
to find ample reference to stellar researches — a sort of 
discussion on the comparative anatomy of suns — but we are 
of opinion that such allusions as that found on page 105 
are quite out of place in a popular book. Sir Norman 
says : " I am glad to see that Sir William Huggins, who 
appears to be ignorant of my quarter-of-a-century-old work, 
has quite recently arrived independently at the same 
conclusion." The arm-chair astronomer doesn't want 
condiment of that sort. As regards the great diversity of 
work to be carried on during the precious moments of 
totaUty, we have in this handy book an admirable description 
such as could only emanate from one thoroughly conversant 
with every aspect of the phenomenon. Difficult as the 
subject is, we can readUy follow the master through every 
labyrinth. The heterogeneous mass of facts gleaned by a 
multitude of observers in all parts of the world during 
eclipses spread over half a century, are here put through 
the intellectual mill and worked into a shape which one 
can appreciate. We see how the sun and stars are, as it 
were, comparable to the several orders of animals, aU 
more or less alike, and differing from one another only Ln 
detail. The large section dealLug with the coming eclipse, 
however, appears to us foreign to the general reader, and 
fitted only to the wants of the few who actually take part 
in eclipse work. It bears a closer resemblance to printed 
instructions from a leader to his followers than hterature 
on a popular subject for the million. The Ulustraticns are 
of very unequal merit. 

Electricity in the Service of Man. By E. WormeU, d.sc, 
M.A. Eevised and enlarged by Mullineux Walmsley, d.sc. 
(CasseU.) Illustrated. 7s. Gd. Perhaps the best evi- 
dence of the worth of this work is its continued issue, 
time after time, in improved form. Evidently no expense 
has been spared Ln making the book a thoroughly reliable 
exposition, in popular phraseology, of the principles which 
underlie all the practical applications of electricity in every- 
day Ufe. The publishers, in this case, certainly give a 
maximum of value for a minimum of outlay — a circum- 
stance which will be sufficiently apparent when we point 
out that there are a thousand printed pages and as many 
illustrations. 

Tlie Method (if Darwin. By Frank Cramer. (Chicago: 
McClurg it Co.) This book is an analysis of the scientific 
method of Charles Darwin. Darwin's works have been 
chosen as a basis on account of— "(1) the desire to confine 
the discussion to the wi-itings of a single author ; (2) the 
fact that his works cover a wide range of subjects ; and 
(3), above all, the fact that Darwin's Lnvestigations, and the 
reasoning based upon them, have furnished the biological 
sciences with their dominant principles "—and also 
because " Darwin's custom of presenting all sides of a case 
very frequently led him to expose the original course of his 
thought and the order of his discoveries." The author 
has chosen an excellent and certainly a neglected subject. 



Januaby 1, 1898.] 



KNOWLEDGE. 



21 



In Darwin's works he has the best foundation possible for 
a study of scientific method, and above all he has planned 
his book well and written it lucidly. 

After a brief explanation of logical processes we have 
the following chapters, each one being discussed in 
connection with well-chosen examples from Darwin's 
works: — Darwin's Views of Method, Starting Points, 
Exhaustiveness, Negative Evidence, Classification, Analogy, 
Induction, Deduction, Unverified Deductions, Erroneous 
Deductions, General Discussions, Logical History of the 
Principle of Natural Selection, and Conclusion. 

We have given an idea of the scope of the book and 
heartily recommend it, especially to those who are starting 
out on scientific work of whatever kind. t)ur only com- 
plaint is that the book is not larger and more exhaustive. 



BOOKS KECEIVED. 

Biirenii of American Ethnnloiji/ — Sirtefn/Ji Annual Separf. 
(Government Printing OflSc'e, Washington.) 

The Sun's Place in Naivre. By Sir Norman Lock ver. (Macmillan.) 
Illustrated. 12s. 

Bit Soadside and River — Gleanings from Natttre's Tields. Bv 
H. iload Briggs. (Elliot Stoek.) Frontispiece. 8s. 6d. 

The Journals of Walter White, formerhi Assistant Secretary of 
the Sot/al Societi/. With Preface by William White. (Chapman & 
Hall.)' Portrait.' fis. 

Observational Astronomi/. Xew Edition. Bt Arthur Mee. 
{Western Mail, Limited, Cardiff.) Illustrated. 29." 9d. post free. 

Modern Architecture. By Heathcote Statham. (Chapman & Hall.) 
Illustrated. 

The Encyclop(edia of Sport. Edited by the Earl of Suffolk and 
Berkshire, Hedley Peek, and F. G. Aflalo. Vol. I. (Lawrence & 
BuUer.) Illustrated. 25s. 

We regret to record the death of Dr. F. A. T. Winnecke, 
at Bonn on the 3rd December, 1807, in the sixty-third 
year of bis age. Curiously enough, the comet which bears 
his name, and having a period of 5-818 years, is expected 
to return to perihelion almost at any time in the early 
part of the present year. He was born in Hanover on 
5th February, 1835, and received his education at Berlin. 
After assisting Encke (Encke's comet, period 3-303 years, 
is also expected about May of this year) at the observatory 
there, and afterwards Argelander at Bonn, he accepted an 
appointment in Russia, and many years of his greatest 
scientific activity were spent at Pulkowa. In ISfis Dr. 
Winnecke took charge of the observatory at Carlsruhe, and 
in 1872 he was nominated Professor of Astronomy at the 
newly founded University of Strasburg. He was elected an 
Associate of the Royal Astronomical Society in 1863. 
Cometary astronomy always had for him great attractions ; 
besides the periodic comet which bears his name he found 
several others, receiving the prize of the Vienna Academy 
of Sciences for his cometary discoveries. 



BOTANICAL STUDIES.-I. 

VAUCHEEIA. 

By A. Vaughan Jennings, f.l.s., f.g.s. 

THE study of plants has till recent years occupied a 
somewhat different position from that of its sister 
sciences. When geology was rousing the interest 
of the intellectual world by its conclusions as to 
the history of the earth, and while zoology formed, 
mainly, the battle-ground of the evolutionists and their 
adversaries, botany still remained a science of the 
collector and the classifier. Only comparatively lately has 
it been able to take its place as a philosophic science on a 
level with zoology. Its acquirement of this position has 
been due to the increasing number of capable students, 



and the improvement of microscopic methods of research. 
It is possible that a recognition of the importance of 
microscopic study has sometimes led botanical teachers 
too far in contrasting their work with that of the earlier 
students of the field and the herbarium. There may be 
room for a protest against the predominance of micro- 
technicality, but the work of the microscope in giving 
botany its proper position in the Ufe sciences can never be 
seriously exaggerated. 

The discovery of the life histories of lower plants, of the 
details of the reproductive processes in higher cryptogams, 
and the demonstration of the relationship between them 
and those of the flowering plants, form one of the most 
striking chapters in the history of biological research. 

Though these results have been arrived at only by long 
labour, by the employment of high magnification and 
refined methods of preparation, it is yet by no means 
impossible for the amateur microscopist to see for himself 
a great number of the more important phenomena in 
question in this line of investigation. It is proposed to call 
attention to a few important types, which form, as it were, 
landmarks in the world of plants. 

As a starting point we may select a common and easily 
obtainable plant in which the reproductive processes 
are simple and readily observed. The species of the 
genus Vaucheriii form green velvet-like patches on 
damp ground or thick felted masses of threads in ponds 
and ditches. With a low-power pocket lens only, the 
branched and interlacing threads can be distinctly seen, 
and it may be observed that some carry small rounded 
excrescences on the side, while others may be darker in 
colour and enlarged ai the tip.* If a specimen is 
mounted in water and examined with a low power of the 
microscope, it will be found that the whole plant consists 
of a cylindrical tube of protoplasm enclosed by a dehcate 
cell wall ;t but there are no transverse walls crossing 
the tubes. If the green colouring matter, or chlorophyll, 
is dissolved out by soaking in alcohol, and the specimen 
treated with iodine solution, or other suitable stain, it 
will be found that the protoplasm contains numerous small 
specialized portions or nuclei which are deeply coloured. ; 

The plant is thus a protoplasmic body with numerous 
nuclei, but the division of these nuclei is not followed by 
formation of new cell walls, and the plant remains uni- 
cellular.? There is a wrong impression produced if we 
speak of the higher plants as aggregations of cells, as if 
they were so many brinks ; and the group of algas to which 
roKt/icr/rt belongs is of special value in reminding us of 
the fact that the cell walls are of secondary importance in 
comparison with the protoplasm and nuclei. It is the 
great series of the Siphonncia which includes a large number 
of marine seaweeds often of considerable size and complex 
structure. To it belong such varied types as the green 
furry Coiliinn, common on the piles of our sea-coast piers ; 
the feathery Bryopsis of our rock pools ; the polymorphic 
Caulfrpa and the calcareous coralline-like Halinu'chi of 
warmer climes ; and the quaint little umbrella-like 
Acetabularia of the Mediterranean. Such variety of form 
and wide distribution suggest a great antiquity for the 
group, and there is little doubt that in the Eocene Dactylo- 
pora and Oralites, and the Triassic GyroporeUa, we have 

* Yaucheria plants are often sterile ; and the enlargement of the ends 
sliould be looked for after the plant has been some time in darkness. 

t By adding a weak (two per cent.) solution of common salt the 
protoplasm will contract away from the wall owing to the abstraction 
of water. (" Piasmolysis.") 

X It is not always easy to demonstrate them by such simple staining, 
and special methods may have to be employed. 

§ The term "' ccenocyte " for such large multinucleate cells is a 
convenient one, and coming into general use. 



22 



KNOWLEDGE 



[Jancaby 1, 1808. 



direct evidence of its geological age. These questions are 
outside our present object, but indicate how far the green 
weed from the garden path might lead ug. 

The special feature we want to observe is the mode of 
reproduction of the plant, and it will be found that it 
propagates itself by two distinct methods.* 

In the first case there is an aggregation of the 
protoplasm at the ends of certain threads, and in time this 
specialized portion makes its way through the terminal 
wall and swims about by means of vibrating cilia, 
which occur in pairs all over its surface. In time this 
liberated mass of protoplasm loses its cilia, settles down, 
develops a cellulose wall, and passes into a resting stage. 
Later on, it germinates and grows directly into a new 



the main axis. Their contents are, however, cut off from 
the latter by a transverse wall or septum. The larger 
inflated bodies contain each a rounded protoplasm mass 
which is the oosphere or egg-cell. The narrower tubular 
structures are the antheridia, and at the right stage will be 
found full of minute antherozoids formed by repeated sub- 
division of the protoplasm and nuclei. These anthero- 
zoids or spermatozoids are minute oval bodies each with 
a pair of cilia, by means of which they move. 

They escape from an aperture at the apex of the 
antheridium, which in most species curves round so as 
to approach the top of the oogonium.* The wall of the 
latter becomes gelatinous at this point, and the antherozoids 
pass through and effect the fertilization of the oosphere. 




A. — Vaucheria arersa. — Tlie lilameDt in the centre slio«s two Oogonia and two Antheridia. The Antlieridium on the 
left is empty, and the fertilized Oosphere in the corresponding Oogonium has developed a thick wall. In the upper filament 
the protoplasm is aggregated at the apex, and shut off by a septum prior to the formation of a Zoogonidium. B. — The 
Coenoeytie Zoogonidium of Vnncheria passing out from the apex of a filament, c. — The Caenocytie Zoogonidium of Vaucheria, 
showing numerous peripheral nuclei, with pairs of Cilia opposite each. D. — An Oogonium, with Antherozoids passing through 
the mucilaginous apical area. E. — Antherozoids (or Sperinatuzoids). F. — Germination of an Oospore or Oosperm. 



Vaucheria plant. This process of renovation of physio- 
logical energy in a special part of the protoplasm is termed 
" rejuvenescence." 

For the other and more important method of repro- 
duction, one must examine the small protuberances which 
occur here and there on the sides of the threads. These 
will be found to be tubular or oval outgrowths from the 
filament enclosed by a cell wall continuous with that of 



* It should be noted the type of oogamoas reproduction liere 
described occurs in Vaucheria only. In the other genera the process 
of reproduction is in some cases still unobserved ; in others it takes 
place by conjugation of similar, or slightly dissimilar, free swimming 
" gametes." 



Subsequently the oosphere surrounds itself with a thick 
protective wall, passes through a period of quiescence, and 
in time germinates, growing at once into a new plant. 

Such is a brief summary of the life history of this 
common but no less interesting plant. 

The type has been selected as affording a simple 
example of oogamous reproduction ; and the important 

* The number and distribution of the oogonia and the form of 
the antheridia differ in the various species. The one chosen for the 
illustration is a fresh-water species, and was collected in a pond near 
Croydon. The commoner V. sessilis. on damp earth, has the curved 
antheridium ; as also V. hamata, V. racemosa, and others. The type 
here shown is the simplest of all, and has not been figured in the 
usual text-books. 



January 1, 1898.] 



KNOWLEDGE 



points to note in connection with our present purpose are, 
firstly, that the " fruit " is only the fertilized oosphere 
without any accessory or surrounding growths ; and, 
aecondly, that when this " oospore " germinates it pro- 
dudes a new plant like that on which it grew. 



THE FACE OF THE SKY FOR JANUARY. 

By Hekmert Sadler, f.k.a.s. 



A FEW small spots may still be occasionally detected 
on the solar surface. 
Conveniently observable minima of Algol occur 
at llh. lOm. P.M. on the 16th, at 8h. 38m. p.m. 
on the 19th, and at 5h. '27m. p.m. on the 22nd. 

Mercury is in inferior conjunction with the Sun on the 
6th. During the last third of the month he is visible as a 
morning star, but under very unfavourable conditions in 
these latitudes, owing to his great southern declination. 
On the 21st he rises at 6h. 23m. a.m., or about one hour 
and a half before the Sun, with a southern declination at 
noon of 20° 51', and an apparent diameter of 7 J". On the 
31st he rises at 6h. 2.5m. a.m., or about one hour and a 
quarter before the Sun, with a southern declination of 
21'" 47', and an apparent diameter of 6j". He is at his 
greatest western elongation (25 ) on the 29th. U'hile 
visible he describes a direct path in Sagittarius without 
approaching any conspicuous star. 

Venus is too near the Sun to be observed, as is also the 
case with Mars. 

Ceres is still in an excellent position for observation. 
She souths on the 1st at llh. 35m. p.m., with a northern 
declination of 28° 4', her stellar magnitude being about 
7i". On the 10th she souths at lOh. 40m. p.m., with a 
northern declination of 28° 87'. On the 20th she souths 
at 9h. 51m. p.m., with a northern declination of 29° 5 . 
On the 31st she souths at 9h. 7m. p.m., with a northern 
declination of 29° 27', her stellar magnitude being about 
7V. During the month she describes a retrograde path 
in Auriga. 

•Jupiter is now beginning to be fairly well placed, as 
regards his times of rising, for the amateur. On the 1st 
he rises at two minutes before midnight, with a southern 
declination at noon of 2° 82', and an apparent equatorial 
diameter of 89 ". On the 11th he rises at llh. 22m. p.m., 
with a southern declination of 2° 43', and an apparent 
equatorial diameter of 40 ". On the 21st he rises at 
lOh. 44m. P.M., with a southern declination of 2° 47', and 
an apparent equatorial diameter of 40|". On the 31st he 
rises at lOh. 4m. p.m., with a southern declination of 2° 48', 
and an apparent equatorial diameter of 41". During the 
greater part of the month he describes a very short direct 
path in Virgo, without approaching any conspicuous star. 
He is stationary on the 25th. 

Both Saturn and Uranus do not rise till long after 
midnight during the month, and they are both very badly 
placed for observation in these latitudes. 

Neptune is very well situated for observation, rising on the 
1st at 2h. 28m. p.m., with a northern declination of 21° 44', 
and an apparent diameter of 2^". On the 11th he rises 
at Ih. 48m. p.m., with a northern declination of 21° 48'. 
On the 21st he rises at lb. 2m. p.m., with a northern 
declination of 21° 42'. On the 31st he souths at 8h. 32m. 
p.m., with a northern declination of 21° 42'. During the 
month he describes a short retrograde path in Taurus, in a 
region barren of naked-eye stars. 

January is a favourable month for shooting stars, the 
most noted shower being that of the Quadrantids, the 
radiant point being in E.A. 19h. 12m. and 53° north 



declination, the greatest display being visible during the 
morning hours of January 1st to 3rd. 

The Moon is full at Oh. 24m. a.m. on the 8th ; enters 
her last quarter at 8h. 44m. p.m. on the 15th ; is new 
at 7h. 25m. a.m. on the 22nd ; and enters her first quarter 
at 2h. 88m. p.m. on the 29th. Many of the larger stars of 
the Pleiades will be occulted on the evening of the 3rd. 

There will be a partial eclipse of the Moon on the evening 
of the 7th and early morning of the 8th. The first con- 
tact with the penumbra takes place at 9h. 11m. on the 7th ; 
the first contact with the shadow at lOh. 57m. p.m., at an 
angle of 169° from the Moon's limb towards the east 
(viewed for direct image). The middle of the eclipse will 
occur at llh. 45m. p.m., about iV'o'''^s o' '^^ ^'s<^ being 
obscured. The last contact with the shadow takes place 
at thirty-two minutes after midnight on the 7th, at an 
angle of 143° from the north point of the Moon's limb 
towards the west. The last contact with the penumbra 
occurs at 2h. 18m. a.m. on the 8th. There will be a total 
eclipse of the Sun on the morning of the 22nd, but it will 
be invisible in the British Islands. 



Ci^css <2Eolttmn, 

By C. D. LooooE, b.a. 



Communications for this column should be addressed to 
C. D. LococK, Burwash, Sussex, and posted on or before 
the 10th of each month. 



Solutions of December Problems. 

(By W. J. Ashdown.) 

No. 1. 

1. Q to R4, and mates nest move. 

No. 2. 
1. R to B2, and mates next move. 

Correct Solutions of both problems received from 
Alpha, J. T. Blakemore, J. M'Eobert, W. de P. Crousaz, 
J. E. Gore, G. Coules, E. C. Noton. 

Of No. 1 only, from H. H. Thomas, A. H. Doubleday, 
Capt. Forde, W. Clugston, G. M. Norman. 

Of No. 2 only, from G. G. Beazley. 

No less than four solvers gave 1. R to B3 for No. 2, 
overlooking the reply 1. ... B to KB. The correct key, 
it will be observed, prevents the dual after 1. . . . B xP. 

H. H. Thomas.— la No. 2, if 1. B to Kt3, Kt to B5 (!), 
and there is no mate. It is a magnificent " try." 

G. (t. Bfirdry. — If B X P, Black retaliates (ch). 

A. E. WJiitehousr. — In No. 2, BxKt is met by the 
Queen moving on to the Rook's file. B x KtP in No. 1 
loses a piece. 

H. S. Bnindieth. — You will have seen that your solution 
of Mr. Challenger's three-mover was correct ; not so that 
of Mr. Slater's insidious two-mover. 

ir. Cluijston. — Thanks for the problems, which shall be 
examined, and if, as we expect, found worthy, receive early 
publication. 

tr. Couh'n. — Thanks for the three-mover. The only 
obvious drawback consists in the two " short mates " after 
two of the King's moves, which look as if they should lead 
to main variations, and lead, therefore, instead, to dis- 
appointment. The problem, we think, could be improved 
by abolishing the two Rooks, and, if possible, utilizing the 
KB more. 



24 



KNOWLEDGE 



[Jantjary 1, 1898. 



PUZZLES. 

By C. D. Locock. 

No. 1. 

Black (3). 




White (ti). 

White compels Black to mate in t'wo moves. 
No. 2. 

Buck (I). 




White (1). 

White, with Black's assistance, is mated in two moves. 
(The Black King has not moved). 




White (6). 

White to play and di-aw. 

[The solution of these positions requires what is known 
as a " liberal interpretation " of the laws of chess, particu- 
larly that relating to Pawn promotions. They are not 
serious studies, but possibly not devoid of amusement.] 



CHESS INTELLIGENCE. 



M. Janowski defeated Herr Walbrodt in their match at 
Berlin by five games to three, a very creditable pei-fonnance 
considering that the score at one time was three to one iu 
favour of Herr Walbrodt, who had only to draw one of the 
next two games in order to win the match. When the 
score reached three all, the match was prolonged for 
another three games according to the conditions arranged, 
and M. .Janowski ^^inning the first two of these became 
the victor. 

The Amateur Championship Meeting will lie held this 
year at Belfast. The experiment is a novelty, and the 
distance from London may militate against a very repre- 
sentative entry. The Irish amateurs, however, will have 
a good opportunity of testing their strength. 

Under the title of " Pollock Memories, " a selection of 
the games of the late W. H. K. Pollock will shortly be 
issued. A biography and portrait will be included, and 
the games will be annotated. The price to subscribers 
will be two shillings and nine pence post free. Address : 
Mrs. F. F. Rowland, 6, Rus-in-Urbe, Kingstown, Ireland. 

We regret to announce the death of the Rev. E. .1. 
HuntEman, president of the Sheffield Chess Association, 
and formerly a well-known figure at the meetings of the 
Counties' Chess Association. 

It is stated that Mr. Lasker, who has abandoned chess 
lately in favour of science, will return to England in the 
summer aud renew his former pursuit. 

In the Championship Tournament of the City of London 
Chess Club the best scores so far have been ol)tained by 
Dr. Smith, Mr. H. W. Trenchard, and Mr. W. Ward. 

A four-handed chess match, played on December l.Sth 
between the British Chess Club and the Four-handed 
Chess Club, resulted in a draw, each side scoring one 
game. 

KNOWLEDGE, PUBLISHED MONTHLY. 



Contents of No. 146. 



The Heart of a 
Grenville A. ^ 

F.o.s. (fllu*tr 



v,'ontinent. By 
. Cole, U.K.t.A., 

ited) 

By W. E. 



285 



The Total Solar Eclipse of 1896. 
(Illustrated) 286 

Artificial Smisi>otB. BytUeR«v. 

A. East 2SS 

British Ornithological Notes, 

Conducted by Harry F. 

WitherljT, f.z.s., m.b.o.u. ... 290 
Letters: — A. T. Mnstenoan ; M. 

L. Lemou; A. G. Moncreiif 

Grahame ; G. Harconrt Hill ... 291 



Science Notes. (Illustrated) ... 
Obituary 

The Beaver in Norway. By E. 

Lydekker, b.a., r.R.s. thhm- 

trnted) 

Notices of Books 

Short Notices 

Books Received ... 

The British Trap-door Spidcr.-I I. 

By Fred. Euock. f.l.s., f.e.s. 

{Illustrated)-. 



By C. D. Locock, 



Plate. — Artificial Sunspots. 



NOTICES. 

Bound volumes of Knowledge, New Series, can be supplied as follows :— 
Vols. I.. II.. III., and VIII., 10s. Gd. each ; Vols. VI., VII., IX., X.. and XI 
(1896), 88. 6d. each. 

Biudine Cases, Is. 0d. each ; post free. Is. 9d. 

Subscribers' numbers bound (includxns case and Index), 23. 6d. each volume. 

Indei of Articles and niustrations for 1891, 1892, 1894, 1395. and 1896 
supplied for 3d. each. 



Ih? 



TEEMS OF SUBSCRIPTION. 

Annual Subscription, 8s., Post Free. 

Knowledge as a Monthly Magazine cannot be registered as a Xewspaj^r 
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Commnnications for the Editors and Books for Review should be addressed 
Editorp, *' Knowledge," tV2S, Hieh Holborn. Uondon W.C. 



Februaky 1, 1898.] 



KNOWLEDGE. 




P^ 



IlLUSTRATED MAGAZINE 

&NCEJL1TERAT 

Founded in 1881 by RICHARD A. PROCTOR. 



LONDON : FEBRVAEY 1, 1S98. 



CONTENTS. 



The Floor of a Continent. By Geenvii.le A. .T. Cole, 

M.R.I. A., F.a.s. {Illustrated) 

Economic Botany. By John E. Jacksox, a.l.s., etc. 
From a Hole in the Mudflats. By Habrt F. Withbrby, 

F.Z.S., M.B.O.U. (Iltustraled)... 
Liquid Fluorine. By C. F. Townsejjd, F.c.s. (Illustrated) 
Letters :—L. Paxton; "G. E. E."; Feed. TVniTTERON; 

Joseph P. Nttitn; J. Ernest Gbubb; W. H. Cock; 

H. U. Jeffert; Ivo F. H. CarrGeegg... 

British Ornithological Notes. Conducted by Harry F. 

WiTHERBY, F.z.s., M B.o.r. (Illustrated) 

Science Notes 

Notices of Books 

Short Xotices 

Books Received 

Total Solar Eclipse, January 22nd, 1898. 

Photograph of the Spiral Nebula Messier 33 Trian- 

guli. By Isaac Roberts, d.sc, f.e.s. (Plate) 
Moon in Eclipse. January 7th. 18 By L. Paxton ... 

The Spectra of Bright Stars. By E. W. M.\under, 

F.R.A.S. ... 

Ancient Red Deer Antlers. By R. Ltdekkee, b.a., p.e.s. 

{Illi'sfrafed} 

Notes on Comets and Meteors. By W. F. Denning, 

F.R.A.S. ... ... ... ... ... ... 

The Face of the Sky for February. By Heebert 

Sadler, f.e.a.s. ... 

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



THE FLOOR OF A CONTINENT. 

By Grenville A. J. Cole, m.r.i.a., f.g.s., Professor of 
Geolo'ifi in the Royal ( 'ollege of Science for Ireland. 

WHEN we consider the thickness of the sedi- 
mentary deposits that lie beneath us at any 
point on the surface of the earth, and 
compare them with the depth of four 
thousand miles that separates us from the 
earth's centre, we may come to regard the whole stratified 
series as a mere blanket on the true substance of the globe. 
Eversincethecrust became solid — ever since theatmosphere 
cooled and the rain began to fall — the earth's surface has 
been subject to denudation, and the dust and mud of ii 
have been carried into the shallow depressions that have 
formed in it from time to time. Wrinklings of the crust 
have uplifted these layers of earth-dust, and have folded 
them, together with more fundamental matter, into 
mountains and continental margins. In the sections thus 
revealed, the sweepings of the earth— the sedimentary 



series — assume to our eyes magnificent proportions ; but 
every now and then we have a glimpse of the real body of 
the earth (or, rather, of its real skin), cleaned from this 
dust of ages. In no spot on the globe have all the strati- 
fied rocks that are known to us been piled continuously 
one upon another ; but, even if this had been the case, they 
would have formed a layer less than twenty-five miles thick. 
If we represent the earth's radius by ten inches, this layer 
would appear, on the same scale, as less than one-sixteenth 
of an inch. 

Where, indeed, denudation has long been active, as in 
the northern regions of Europe and America, we find 
ourselves in the presence of a vast bared surface, in which 
there is little to remind us of the sediments of ordinary 
geological periods. Here and there, isolated relics, like 
the marine .Jurassic beds of the island of Ando, suggest 
to us the coating of stratified rocks that once spread over 
much of this denuded area ; but the main masses are of 
Pre-Cambrian age — that is, they underlie the beds that 
contain the oldest clearly recorded fauna on the globe. 
Here, then, we seem to be in touch with the true substance 
of the crust — with the floor on which our filmy continental 
or oceanic accumulations rest. 

Without entering into microscopic details, we may see 
that there is a remarkable uniformity of character in the 
rocks that form this floor. Gneisses, resembling granites, 
but with a " streaked out " and even banded arrangement 
of their constituents, form the largest portion of the 
mass. Their chemical composition* almost always shows 
a high percentage of silica, and the alkalies amount to 
five or even eight per cent. Their essential structure, the 
" foliated " arrangement of their mineral constituents, 
may have been induced in them by pressure after they had 
become practically solid, or by the flow of the whole mass 
while the crystals were still in course of construction. 
The larger constituents thus possess a lenticular form, as 
if drawn out at their edges ; and these lenses lie in similar 
positions throughout considerable masses of the rock. 
The smaller constituents seem to have flowed round 
about them, streaming on in fairly parallel layers ; and 
thus "foliation-planes" have been set up, along which 
even coarse-grained gneisses tend to split when struck. 

In many gneisses there are distinct rock-bands, some 
bands, for instance, resembling mica-schist, while others 
resemble fine-grained granite, rich in quartz and felspar 
(Fig. 1). In such cases it is quite possible that one type 
of rock has intruded into another in fine parallel sheets,! 
or that a viscid mass of varied composition has been pressed 
out underground, and so has received a gneissic structure.! 
Sometimes above the typical gneisses, and sometimes 
associated with them, there is usually a series of crystalline 
rocks of much finer grain and of greater variety of com- 
position. Foliation is present in them, and they are 
classed collectively as schists. Mica-schist, a foliated 
mixture of quartz and mica (usually muscovite), and 
commonly accompanied by red-brown garnet, is the type 
most extensively developed. The schists present many 
analogies with sedimentary rocks, and many mica-schists 
have undoubtedly arisen from the extreme alteration 
of sediments under heat and pressure ; but the planes of 
foliation only rarely correspond to those of original depo- 
sition, and the crystalline character of the constituents 

* See, for instance. Roth, " AUgemeine imd chain. Geolo^ie," Bd, 
II., p. 397. 

t Compare A. C. Lawson, " A Multiple Diabase Dvke," American 
Geologist, Vol. XXVI., p. 29(5. 

X See Sir A. Geilde and J. J. Teall, " On Banded Structure of 
Gabbros in Skye," Quart. Journ. Geol. Soc, Vol. I>., p. 6.57, and Plate 
XXVI. 



26 



KNOWLEDGE 



[Febhuaky 1, 1808. 



has been, to say the least, intensified during alteration. 
Modern observation in this matter has supported the views 
of that master geologist, Charles Darwin, who opposed his 
opinion to that of Sedgwick, Lyell, and most of the teachers 
of his day.* 

The present tendency is to regard the ancient schists and 
gneisses as a complex mass of formerly molten materials, 
which have successively intruded through one another, and 
which have been, as a whole, deformed and foliated by subse- 
quent pressures. I Sir A. Geikie suggests that the " over- 
lying graphite-schists, mica-schists, and limestones of the 
Gairloch and Loch Carron may thus be surviving 
fragments of the stratified crust into which these deep- 
seated masses were intruded," the latter masses now 
forming the Lewisian gneiss of Scotland. 

In almost every area of ancient gneissic and schistose 
rocks, there is found a series of true sediments, deposited 
across the worn-down edges of the foliation -planes, but 
still earlier than the fauna known as Cambrian. Examples 
are the Huronian de- 
posits of North America, 
and the little - altered 
Torridon sandstones 
that form the bulwark 
of western Sutherland. 
The occurrence of frag- 
ments of the funda- 
mental rocks in this 
overlying series shows 
that the essential struc- 
tures of the old complex 
gneissic group had been 
impressed upon it long 
before Cambrian times. 
Prof. Bonney ] is so 
struck by this fact that 
he regards the banding 
of the gneisses as due 
to conditions which 
have not repeated them- 
selves since ordinary 
sediments began to be 
deposited upon the 
globe. Whether we 




FiQ. 1.— Block ,,f One 



complete passage from sediments into schists, and from 
schists into gneisses, and urged that gneiss was the ultimate 
stage of the alteration of ordinary sediments. 

At other times the fundamental gneissic mass is found 
to send ofi' dykes and veins into the overlying rocks, which 
we have hitherto regarded as being far younger than the 
gneiss. Sometimes these appearances may be due to the 
intrusion of a granite through both series, its close 
resemblance to the gneisses allowing it to lie among them 
undetected. But another solution has been offered, which 
presents us with a new aspect of the continental floor. 
Mr. .Joseph Nolan, in 1879, suggested that granitic 
intrusions might arise from the depression and remelting 
of an ancient metamorphic series. This series would 
remain for the most part " fundamental" ; but its offshoots 
would, of course, be later in age — /.c, in date of consolida- 
tion — than the rocks invaded by them. Prof. A. C. 
Lawsont has attributed much of the structure of the 
Laurentian gneisses of Canada to this second period of 
flow, and has provided 
us with excellent 
photographs of gneiss 
including fragments of 
the overlying series. 
Similar phenomena are 
recorded by Dr.Gregory ; 
at the junction between 
what was regarded as 
" fundamental gneiss" 
and the schists of the 
Western Alps ; and the 
conclusion is arrived at 
that these central 
gneisses of the moun- 
tain-chain are as recent 
as Miocene and even 
Pliocene times. M. 
Jlichel-Levy,; as is now 
well known, has proved 
that the gneiss- granite 
of Mont Blanc 



wentv centimetres long, from Co. Mayo, showing . • • ., .1 ■ f 

(i.) curving upper surface formeil bv fracture along a foliation-plane ; (ii!) dissimilar '•"ll^l^S in tne ScniStS 

materials in different bands, the lighter ones consisting of quartz and felspar, and Surrounding it ; SO that 

the darker ones being rich in dark mica ; (iii.) a lenticular mass at the righi-hand here again we fail to 

adopt his view, or the «'°<*. "'"' t'le darker layers (lowing round it. recognise the true con- 

more rigidly iiniformi- tinental floor in its new 

tarian one of Sir Archibald Geikie, we must see in the guise of an igneous invader. General McMahon, again, 
complex floor of schists and gneisses the oldest rocks sees in the gneissose granite of the Him:ilayas a rock of late 



For our present 



accessible to us in the earth's crust, 
purposes they are " fundamental." 

Yet the upper boundary of the fundamental gneiss 
presents difficulties when it comes to be surveyed in detail. 
At times, subsequent pressures have obliterated the 
discordances between the gneissic surface and the over- 
lying stratified deposits ; the great earth-mill has rolled 
all these rocks out together, and has produced a community 
of structure, and even an appearance of continuity.; So 
that there is little wonder that the older geologists saw a 



* " Geological Observations on South America," Minerva Library 
edition, pp. 439 and 440. 

t Compare Sir A. Geikie, " Ancient Volcanoes of the British 
Isles," Vol. I., p. 117; and C. R. Van Hise, " North American Pre- 
Cambrian Geology," SLvteenth Annual Report, U.S. Geol. Survey, 
1895, p. 753. 

X "The Foundation-Stones of the Earth's Crust," Nature, Vol- 
XXXIX. (1888), p. 92. Compare a very interesting paper on crystalline 
gneisses, by J. Lomas, P.G.s., Oeol. Magazine, 1897, p. 537. 

§ See Van Hise, op. cit., pp. "30 and 752. 



Eocene age, and regards its foliation as the result of pressure 
acting while it was still a viscid mass. It is doubtful, 
indeed, if the gneissic cores of mountain -ranges ever 
represent the oldest rocks of the chain. Probably they 
have no age but that of the folding of the strata. The 
complex arch of stratified rocks was formed, and fused 
material (often derived from the continental floor) was 
forced into it as it rose. 



* " Metamorphic and Intrusive Bocks of Tyrone," Oeol. Mag., 
1879, p. 1.59. 

t " Geologv of the Rainv Lake Region," Geot. Snrv. of Canada. 
Ami. Report,'lSb7, pp. 130.140. 

X " The Waldensian Gneisses and their Place in the Cottian 
Sequence," Quart. Jouni. Geol.Soc, Vol. L., 1894, pp. 235, 261, 270, 
and 273. 

§ Bull, lies Services ile la Carte gi'ol. de la France, No. 9 (1890). 
See also Gregory, '' Geologv of Western Alps," Science Progress, 
Vol. III., p. 169. 

II Proc. Oeol. Assoc, Vol. XIV. (189.5), p. 93, and Geol. Maq, 1897. 
p. 304, etc. 



February 1, 1808. 



KNOWLEDGE 



27 



If doubt hangs round these masssB, which were once 
thought to be ribs of the primordial earth, but which 
appear to be often of very modern origin, we may look with 
more respect upon the fundamental rocks exposed in broader 
areas. Scandinavia and the north of North America have 
already been referred to ; but bosses of the continental 
floor appear in many places, entirely surrounded by the 
deposits of later days. In most of these cases the sur- 
roimding areas have subsided, leaving the resisting ribs 
and pillars of the old crust standing firmly. As the tloor 
of the continent must also have subsided, to allow of the 
falling in of the upper layers, it is very likely that some 
contrary upward movement was at the same time given to 
these bosses and plateaux which now stand above the 
general level. While subsidence predominated, owing to 
the contraction of the earth's interior, we may conceive a 
buckling of the floor, some parts rising as others fell. 
The sediments slipped into the new hollows from the flanks 
of the masses across which they once had stretched ; so 
that a series of dis- 
locations (faults) —> 

now surrounds the 
exposed and ele- 
vated portions of 
the floor. 

Suess* and 
Neumayr f have 
emphasized most 
strongly the part 
played by subsi- 
dence in bringing 
the resisting knots 
of the continental 
floors to light. The 
word " horst," used 
by Suess for a ridge 
left upstanding be- 
tween two adjacent 
areas of subsidence, 
has become extend- 
ed so as to include 
any old mass 
bounded by faults, 
along which 
younger strata have 
slipped down. 
Favourite examples 
are found in the 
Black Forest and 

the Vosges, which are bold highland areas composed mainly 
of "fundamental" rocks. The Feldberg in the former 
still rises 4901 feet above the sea, and the Hoheneck 
near Gerardmer gives us 4580 feet. On the north-east 
we have to cross the Danube to the Bavarian forest, 
and on the south-west we must reach the central plateau 
of France, to find the compeers of these high irregular 
masses. 

In the uplands of Bohemia we find a wide exposure of 
the floor of Europe, giving us a strange undulating 
granite land. Every hollow is set with lakelets, beside 
which the villages are placed. One may travel day after 
day across the plateau, at heights of eleven hundred to 
thirteen hundred feet above the sea. Now one ascends 
a gentle swelling upland, but the towers of the town 
in the next hollow can already be descried across the 
ridge. The descent is thus similarly gentle ; and the 

* " Dcs AntUtz der Erde," Bd. I. (1883), pp. 167, 265, etc. 
t "ErrgescWchte," Bd. I. (1.886), pp. 309, 327, 331, etc 




1"IG. 2. — Eidge ot Amicut Ku. L.*, .-ecu iron 
prominence in the landscape. (From a 



broad surface of the ancient rocks is only occasionally 
broken by a valley. 

The central plateau of France presents very different 
features. It is far more broken, far more cut into; and 
portions of it, rising above the general level, are covered 
with heather, and seem to form independent moorland 
ranges. But, when we enter fairly on it, we soon recognise 
the old uniform surface of the plateau, though hundreds 
of streams have carved deep hollows, into which we descend 
from time to time. Thus, in the western portion of the 
plateau, we cross river after river running to the Atlantic, 
notably the lordly Menne at Limoges, the Briance among 
the mountains of Pierre-BulHere, the Vc'zi-re at the foot of 
the steep street of Uzerche, and many other minor streams, 
until we drop from the rim of these antique highlands into 
the great valley of the Correze. The roads are carried, 
however, as far as possible along the ridges between 
adjacent valleys ; we catch no gUmpse of the streams until 
we actually cross them, lost as they are in the deep brown 

cuts that they have 
made ; and looking 
across country from 
one high -perched 
village to another, 
the upper sturface 
seems wonderfully 
level — a plateau 
undisturbed by 
structural lines. It 
is as if we covdd 
sweep Sutherland 
clear of the Torri- 
don sandstone and 
other stratified 
masses, the rubbish 
heaps of the early 
days of denudation, 
and reveal the stUl 
older floor of funda- 
mental gneiss and 
•_,'ranite upon which 
these strata were 
laid down. 

Upstanding 
blocks, then, in 
some places, vast 
denuded areas in 
othsrs,reveal tous, 
across a continent, 
the nature of the floor on which it lies. The British Isles, 
as so often happens, serve us as a model of these larger 
geological features. If the Outer Hebrides recall to us the 
worn-down surface of North America, from the great lakes to 
Hudson's Bay, the hills east of Church Stretton (Fig. 2), the 
JIalvem range, and the little plateau of Charnwood Forest 
are excellent examples of the " horsts." Formerly these 
masses were held to be igneous, and later than the rocks 
through which they now protrude. The patches of old strata 
upon their flanks were not unnaturally regarded as altered 
products of the easily recognisable beds on either hand. But 
more detailed mapping has shown that the floor of Europe 
is here brought to our notice through the covering of strata 
that once stretched ttniformly from Wales to the eastern 
counties.* Old ridges, which were buried even in Cambrian 
times, have reasserted themselves, their horst-like nature 
being often evidenced by the great faults that can be traced 



* See, for instance, Geologists' Assopiation, Record of Excursions, 

. 412. - . - 



I i^jnircli Strrttou, Shrop;.liiri',slioHing tliei: 
photograph by Mr. J. J. Cole, p.h.a.s.J 



28 



KNOWLEDGE 



[Febbuary 1, 1898. 



along tbeir flanks. The fine range of the Malverns — the 
backbone of the English Midlands — may thus owe much of 
its pre-eminence to the subsidence of the country to the 
east, whereby the Trias now forms a lowland which is easily 
flooded by the Severn ; while the Carboniferous rocks, 
which cause such mountainous country further north, are 
safely hidden away far below the reach of denudation. 

The floor of a continent is, then, a reality — something 
that supports this wrinkled film of scarps and furrows, of 
level plains and axial ridges, on which we spend our lives. 
If we cross a continent and an ocean, we say that we have 
seen something of the world — much as a fly who should 
contemplate St. Peter's from the weathered surface of the 
dome. The true world lies beneath us ; and as yet the 
only certain clue that we possess as to its constitution is 
its well-determined mean specific gravity. This figure is 
5-6, as against 2-6 or 27 for the mean specific gravity of 
the accessible crust. Denser masses than those familiar 
to us in the crust thus seem to form the great body of our 
planet ; and it is very likely that our continental floors 
are really portions of the lightest layer on the globe. 
Processes of denudation, acting on the surface, have 
separated the constituents of this layer; have collected, for 
example, the heavy iron-ores at some points, or have 
formed carbonates and sulphates and hydrous compounds, 
of various densities, at others ; while heavier materials, 
forced up through fissures from below, have added sheets 
of basalt or bosses of gabbro to the manifold rocks of the 
outer film. Nor must we forget that the remelting of the 
old crust has locally enabled it to absorb masses above it, 
and has thus increased its mineral complexity. The 
general mass of the " floor," however, has remained much 
as it was — a series of granites and gneisses and highly 
siliceous schists of comparatively low specific gravity. 

We must refer in conclusion to Mr. Osmond Fisher's 
" Physics of the Earth's Crust " ■ for a discussion of how 
this light siliceous layer is probably thicker beneath the 
continents and thinner beneath the oceans. Both the plumb- 
line and the pendulum tell the same tale. The former should 
be drawn out of the perpendicular by the attraction of high 
continental land ; and from a survey of the mass of land 
that stands, in any case, above the level of the sea, 
the theoretical amount of deflection of the plumb-line can 
be calculated. But the actual deflection has been found, by 
experiments in India, to be less than the calculated amount. 
Archdeacon Pratt, after much labour, arrived at this con- 
clusion ; and Sir George Airy, in 1855, pointed out its pro- 
bable explanation. The attraction of mountain-masses, and 
consequently of continents as a whole, is deficient, because 
the light crust is actually thickened beneath them ; hence, 
for every great anticlinal ridge or bulge upon the surface 
a corresponding ridge or bulge seems to be formed down- 
wards, displacing the more dense and basic matter below. 
Mountains have " roots," therefore, and tablelands are 
similarly thickenings of the light outer crust. If there is 
even a thin liquid layer — to make the smallest demand — 
beneath the consolidated crust, it is easy to see how lateral 
pressure in the crust may produce a bulge in two directions, 
both upwards and downwards. The continental floor, on 
these grounds, becomes still more real to us, and may be 
compared to the mass of concrete on which buildings are 
floated in equilibrium when foundations have to be laid in 
oozy mud or sand. The formation of these knots in the 
crust need not be opposed to our view of the instability of 
continents and ocean-basins ; for the lower layers of a 
continental mass may become melted off, in accordance 
with Mr. Fisher's own "theory of the earth," while the 

* Second edition (1889), pp. 124, 195, 204, etc. 



thinner ocean-floor may become thickened in its turn by 
compression. Most of us, however, must be content to 
return from these somewhat speculative regions to the 
continental floor itself; and in the relations of the rocks 
that form it, in their mode of consoUdation, their inter- 
penetration, and the deformations sufi'ered by them, we 
shall find absorbing problems for a lifetime. 



ECONOMIC BOTANY. 

By .John R. .Jackson, .\.l.s., etc., Keeper nf the Museums, 
Roijal (iardens, Kew. 

INTRODUCTOEY. 

THE first and by far the most important attempt, 
in this and perhaps in any other country, to 
elucidate and make popular the economic side of 
botanical science was begun by the late Sir W. .1. 
Hooker, when in 1847 one room of the building 
now known as Museum No. 2 in the Royal Gardens, Kew, 
was fitted up for the purpose to which it has ever since 
been devoted. 

The foundation and progress of the collections now 
contained in the three Museum buildings in the Royal 
Gardens is certainly remarkable. It was in the year just 
mentioned that the building, which had hitherto been 
used partly as a storehouse for fruit, " was added by 
command of Her Majesty to the Botanic Garden proper." 
The nucleus thus formed consisted of the Director's 
private collections, presented by himself. To quote from 
the official guide to the Museums ; "No sooner was the 
establishment and aim of the Museum generally made 
known than contributions to it poured in from all quarters 
of the globe, until in a few years the ten rooms of the 
building, with its passages and corners, were absolutely 
crammed with specimens. Application was therefore 
made to Parliament by the Chief Commissioner for a 
grant to defray the expense of an additional buildini; for 
the proper accommodation of the objects, and the house 
occupied by Museum No. 1, opened to the public in the 
spring of 1857, is the result." 

From that time the collections have gone on increasing 
in importance and value till at the present time they 
stand unrivalled all the world over. Besides this, in 
almost every botanic garden at home and abroad, as well 
as in most teaching centres and in large towns, museums 
on the system of those so well known at Kew have been 
established. 

The result of all this has been the diffusion of a 
knowledge of economic botany, so that at the present 
time the subject is taken up even by our elementary 
schools, most of which have their own small collections 
for teaching purposes. It must be confessed, how- 
ever, that until the last ten or twelve years the subject 
did not command that attention its great importance 
deserved. The structure of plants, their affinities, their 
geographical distribution, and similar points attracted the 
attention of the scentific worker, who gave no consideration 
to their properties and uses. The connection, however, 
between the purely scientific and the economic sides is 
very apparent upon a moment's consideration. Thus, in 
some natural orders there is a distinct property running 
through the plants which constitute the order, which may 
serve as an indication of their botanical affinities and also 
prove them to be of economic value or otherwise. Such, for 
instance, we find in the Malriiceie, where the inner barks 
for the most part abound in long soft fibres, and the roots 
and fruits of many are mucilaginous — the roots of the marsh 



Februarv 1, 1898.] 



KNOWLEDGE 



29 



mallow (Althcea oflicincilis] and the fruits of gombo or 
ochra (Hihiscus «sc»/ph/ms) being illustrations — while in the 
allied order, Sterctiliuccic, the fibrous inner barks are inter- 
laced. Again, in (Jcntiaitea- all parts of the plants abound 
in a bitter principle, which makes them valuable as tonic or 
febrifugal medicines. Further, some natural orders abound 
in milky juices, some of which are wholesome while others 
are poisonous ; and othtrs, again, upon solidifying become 
elastic and form caoutchouc or india - rubber, and in 
this connection may be mentioned such orders as Arto- 
i-arpetE, F.uphorhiiuca, Apovynmrce, and Asch-piadca. A 
knowledge, then, of the properties of the several natural 
orders, or of any group or genua of plants, is not only 
of assistance in their determination, but is also of 
much help in deciding their economic or commercial 
value. As a proof of this we may give but one illus- 
tration. It not unfrequently happens that new oil 
seeds make their appearance in the Liverpool or London 
markets, and, being unknown to the brokers, do not find 
buyers until their botanical affinity is determined, and 
their harmless or poisonous nature thus known. Serious 
coDsequenceB might otherwise arise if the seeds were 
allowed to be crushed, and the cake sold for feeding 
cattle. This is only one example of the importance of a 
knowledge of economic botany in connection with trade and 
commerce. That it is a great factor in the development 
of the resources of the vegetable kingdom all over the 
world we hope to show in succeeding articles, in which we 
propose to treat of the principal products in this great 
kingdom of nature. 



FROM A HOLE IN THE MUDFLATS. 

By Hakry F. Witherby, k./.s., ji.b.o.u. 

IN the months of December, January, and February 
the mudflats of our tidal rivers are not nearly 
so attractive to the ornithologist as in the autumn. 
Then the birds are much more numerous in 
species if not in numbers, owing to a great influx 
of migrants staying here and there for a brief visit on 
their way to the South. Amongst this host of migrants 
there may always be the chance of picking up a rare 
bird, and it is this chance, and the variety of the birds, 
which makes shore-shooting so much more interesting 
in autumn than in winter. Then, again, unless there 
is a hard and continuous frost, the birds become much 
wilder, and therefore much more difficult to obtain as 
the season advances. For instance, in August, when 
the young knot, godwit, sanderling, and others have just 
arrived from the North, they will often allow you to 
approach them on the open mudflat to within a few 
yards. In December these same birds will not allow 
you to come within two hundred or three hundred yards 
of them in the open. In the winter, therefore (except, 
as has been said, during a frost), the shore-shooter has 
to work very hard and resort to many stratagems to 
obtain the birds he wants. 

There are many ways of getting within gunshot of 
these wary birds. They may be stalked if there is suit- 
able cover, and the birds are near enough to it. This 
method entails careful marking down, generally a large 
amount of crawling, absolute silence, and frequent 
disappointments. The joy of one success, however, will 
compensate for a dozen failures. Another method is to 
hide behind a bank or in some suitable place near the 
high-water mark, and wait for the tide, which, as it 
advances, drives the birds before it and gradually within 
range of the hidden gun. 



Yet another way, if you know the ground well, and have 
studied the flights of the birds over the land at high tide, 
is to lie hid in one of these lines of flight and take your 
chance of their flying within shot. 

It will be easily seen that all these methods are very 
uncertain, and that their success or failure is influenced 
greatly by the element of luck. 

There is no method known to me in shore-shooting that 
is certain to be a success, but perhaps the best all-round 
way of obtaining shore birds in the winter is to dig a hole 
in the mud, sit in it, and wait. This plan certainly 
does not appear a very cheerful one at first sight, but to 
anyone who is a really keen ornithologist it will soon 
prove a most interesting occupation, notwithstanding the 
cold, the cramped position, and the slimy mud. 

As many of the readers of Knowledge have probably 
never either dug or occupied a hole in the mudflats, 
a brief description of how it should be done may prove 
acceptable. I was taught the art by a Yorkshireman,one 
of the best 'longshore-shooters I have ever known. 

Carrying our guns, game bags, tieldglasses, a long-handled 
wooden spade, and a bundle of straw, we arrived at the 
river bank just as the tide was at its lowest ebb. It 
would be, I think, impossible to successfully dig a hole 
where the mud is a dead flat, because the mud thrown out 
of the hole is black, and being scattered about on the 
brown surface would scare the birds away for a mile round. 
There is, however, usually on every extensive mudflat a 
part which is more or less broken up into a wavy sort of 
formation. 

We made our way to an excellent place of this sort about a 
mile from the shore, where long parallel ridges about three 
feet wide were separated from each other by troughs full of 
water. We selecteil a good wide ridge, flanked on either 
side by fairly deep ditches, and commenced operations. 
The bundle of straw was put on the mud, and on it were 
balanced my friend's gun and game bag, and his coat, lor 
digging a hole in the mud is warm work on the coldest 
day. First of all a circle was marked out, and then the 
digging commenced, and the mud as it came out was 
thrown into the troughs at the side. The mud stuck. 




every now and then, even to the wooden spade, which had 
to be continually lubricated in the water to make it run 

* If tlie shoi-e-sliootci- is fucky enougli to be living on the spot, he 
may tliink it wortli while to sink a tub in the llats. and thus make 
things more eomfortable : but few have the chance of doing this. 



30 



KNOWLEDGE. 



[Febbuaby 1, 1898. 



smoothly. Having dug a hole about three feet in diameter 
and three feet in depth, half the area was dug out another 
two feet in depth. When this was done, and the straw 
was put in and arranged round the sides, there was a 
capital and snug retreat, if a little dirty, with a good seat 
and plenty of room for the legs. 

The hole should be dug to such a depth that when 
sitting in it the eyes are just above the surface of the 
mudflat. Of course the shape of the hole can be varied 
to suit its position. The water will not ooze through 
the mud, and a well-dug hole will keep quite watertight 
until the tide flows into it ; but sometimes the stratum 
of mud is not very deep, and when the sand at the 
bottom is reached the water will immediately come 
through and soon flood the hole. A shallow oblong 
hole, of the same depth all over, can easily be made 
in this case. The plan then is to sit at the bottom and 
stretch the legs 
out, but this is 
a more cramped 
position than the 
other, and shoot- 
ing is conse- 
quently made 
more difficult. 
Before getting 
into the hole, 
great care should 
be taken in 
levelling and 
hiding as far as 
possible the mud 
that has been 
thrown out, and 
the fewer the 
footmarks near 
the hole the 
better. 

Birds, and 
especially the 
wading birds, 
have wonderfully 
keen eyes, and 
the slightest 
elevation or dark 
spot can be seen 
ata long distance 
on a mudflat. 

Once seated in 
the hole the first 
thing is to make 
yourself com- 
fortable. If the 

weather is cold the more straw you have and the thicker 
your clothes the better. Little " pockets " can be gouged 
out of the sides of your retreat, and filled with straw, 
forming convenient receptacles for cartridges and field- 
glasses. Cartridges should always be handy, because it is 
not easy to get at coat pockets when crouching in a hole. 
Nest a few little wisps of straw should be stuck here and 
there round the rim of the hole on which to rest the gun. 
Great care should be taken over this simple precaution. 
In the excitement of the moment — say, when a big flock 
of birds is approaching — the muzzle of the gun is apt to be 
stuck into the mud, and when the gun is pulled away the 
barrels are securely "corked." The result is a damaged 
gun and perhaps a great opportunity missed. 

When everything is arranged to your satisfaction you 
begin to look about you. You have the same view as a 



bitd would have when it is sitting upon the mud — and an 
extraordinary view it is. Nothing but a flat expanse of 
mud stretching for miles all round. There is nothing 
to guide the eye — there is no correct idea of size or 
distance ; a small stake a mile away looks enormous and 
quite near. There is no living thing to be seen — nothing 
but miles and miles of mud rolling away to your limited 
horizon, where the water can now and again be made out 
as it sparkles in the rays of a winter sun. Suddenly there 
is a swish of wings behind you, and a little dunlin appears 
like magic, and settles down within a few yards. Then 
comes another and another, until there is a small flock of 
them. Dunlin are silly little birds, and quite unlike the 
other birds of the mudflats. They never see danger 
until it is too late to escape. So these birds come and 
settle down within a few yards of a deadly gun, and, with- 
out looking round, immediately begin to feed. Common, 

tame, confiding, 
inconspicuous, 
low - bred httle 
birds, they might 
appropriately be 
termed ihe 
sparrows of the 
mudflats. Never- 
theless, they are 
very interesting 
to watch when 
they are near, 
and ignorant of 
the presence of a 
human being. 
They feed very 
industriously — 
running up and 
down the mud, 
probing with 
their slender biUs 
here and there, 
and singing in a 
soft and pleasing 
way all the time. 
Now and again a 
couple wiU have 
a little dispute 
about some 
dainty morsel, 
which results in 
all sorts of little 
antics. There is 
never a stand-up 
fight, but just a 
little bickering 
and pushing and dancing about and the affair is over ; one 
of them gets the tit-bit, and the feeding goes on as peaceably 
and assiduously as ever. The birds will walk all round 
you, but sooner or later one comes within a foot of your 
face, and then suddenly his terrible danger dawns upon 
him. He is startled out of his life, and flies up with 
a "tchurr," uttered as though he had a sudden catch 
in the breath. The others follow suit, and you are once 
more left in solitude. 

Now is the time to use the field-glasses. Ever so far 
away there is a huge black mass on the mud — it is a flock 
of, perhaps, six or eight thousand knot. Although to the 
naked eye it looked like a great black cloth spread out upon 
the mud, if you look carefully with the glasses you wUl see 
that ii is continually moving. Every moment a bird flies 
up to change its ground, and shows its white under-side, 




The Bar-tailol G,.ilwit. I'liotograi.lirtl from LiU' l.v R. B. L.nU'e 



February 1, 1898.] 



KNOWLEDGE, 



oL 



which looks like a flake of snow against the black mass. 
Beyond this flock there are a number of large dark objects 
moving about. By their shape and the manner in which 
they feed you can tell they are curlew, although they are 
too far off for you to see their long curved bills. 

Five fair-sized birds have risen from the mud and come 
flying towards you. At flrst you cannot make them out, 
but as they come nearer their long and slightly upturned 
bills and light brown plumage can be seen, and you put 
them down as godwit. Now, if you are on the east coast 
it is not every day you will see a godwit in the winter, so 
you are particularly anxious to get one of these birds. As 
ill luck will have it they seem to be passing right out of 
range, so you whistle " whee-whaup-whaup, whee-whaup- 
whaup." They have heard it and round they come. You 
keep on whistling and crouch low, and the silly birds come 
right over your head. Bang ! bang ! \'ou have got one but 
missed the other, and you consider yourself lucky that 
they answered to the call. 

Mr. R. B. Lodge, who is well known as a very successful 
bird photographer, has very kindly allowed me to here re- 
produce a photograph of a living godwit. When the 
unapproachable nature of shore birds (on account of their 
shyness and the want of cover) is taken into consideration, 
this photograph may be regarded as a triumph of skill and 
patience. I might here advise j\Ir. Lodge to try photo- 
graphing birds from a hole in the mudflats. I feel sure it 
would prove a success. 

After retrieving the godwit, and when you are once again 
settled down, you find that the tide has been slowly but 
surely creeping up, and as it comes so it drives in the birds 
with it. There are usually dunlin, grey plover, ringed 
plover, and a few other birds (according to the time of 
year), fairly near the shore even when the tide is right out ; 
but the big flocks of knot, the flocks of duck and geese, 
the parties of curlew and others, generally feed right at 
the edge of the water. When the tide was far out, and 
there were a number of square miles of uncovered mud, it 
was just a chance if a flock, or a single bird even, came 
within the limited range of your gun ; but now, with the 
tide well up, the feeding grounds circumscribed, and the 
flocks on the move, you will have the best chances of the 
day. 

Lucky indeed is the man who, as he crouches in his 
hole, hears a deafening roar and rush of wings, and looks 
up to find one of those vast flocks of knot sweeping along, 
forty yards above his head. It is an impressive sound and 
a thrilling sight, and neither will be forgotten. 

If the hidden gunner is not overpowered by the spectacle, 
and has the presence of mind to tire, he will pick up a 
score or two of birds than which none are better eatint,'; 
but the sight and sound alone will be a rich reward for 
many hours of cold and dreary waiting. 

It is, indeed, rire to be so close to one of these enormous 
flocks on the wing, but there are other good things that 
will come to the man who perseveres, even in sitting Ln a 
hole on the mudflats. 

The curlew — one of the wariest of birds — may be 
watched at close quarters and brought to bag. 

I well remember one winter's day. I had been watching 
and waiting without success for four hours in a hole 
which had taken some labour to dig, as more than one 
blistered finger testified. The tide was rapidly approaching 
and all chances of sport would soon be over for the day, when 
eighteen curlews suddenly appeared and settled down within 
two hundred yards of me. They commenced feeding, and 
to my disgust I soon saw that they were slowly walking 
further and further away. As a last resource I began to 
whistle softly " courlieu cur-cur-courlieu." They heard 



me and stopped feeding. I whistled louder and louder. 
They did not seem quite satisfied, but nevertheless they 
turned and began to slowly walk towards me, feeding as 
they came. I continued to whistle, and as they got nearer 
I could see them plainly and watch their every action : 
the leisurely way they fed — walking along in a stately 
fashion, and every now and again looking round or 
stepping aside to probe their long curved beaks up to the 
very base in the soft mud. Their manner struck me as a 
great contrast to that of the dunlin, with his dumpy little 
body, his quick run and eager probing here, there, and 
everywhere. But I soon began to wish the curlew would 
walk a little faster. I was becoming tired of whistling, and 
the tide was getting very near and would soon flood me 
out. At last one of the curlew was well within range and 
several more were fairly near. The water began to trickle 
into the hole, so I jumped up and made sure of the bird 
nearest to me, but missed with the second barrel. Had I 
been an older hand I should have done as a friend of mine 
once did. There was a flock of Brent geese walking 
towards him. He waited patiently until one of the birds 
actually came to the edge of the hole, and was naturally 
surprised to see a man there. The man jumped up and 
shot a goose a little distance off, and then bowled over the 
one which had been so near to him, and had by that time 
flown away about forty yards. 

One has to be careful when walking off the mudflats at 
night. The ridges of mud are slippery and deceptive. I 
once fell full length into two feet of water, and drove my 
gun into the mud up to the breech. A friend of mine 
once stepped into an old hole which was full of water. 
Luckily, he went in feet first. Had it been head first, it 
is unlikely that he would have got out again. 

A carefully dug hole will last two or three days before 
it either falls in or becomes silted up. Of course it fills 
with water and has to be baled out before it can be 
occupied again, and however dry it is baled it is never so 
comfortable as a freshly dug one. 

In conclusion, let me recommend ornithologists to make 
a trial of " holeing in the clays." A close acquaintance 
will be made with a number of very wild birds, and many 
pleasant hours will be spent studying their ways. More- 
over, there is certain to be some sport, and there may be 
such a chance as comes to the orinary man but once in 
a lifetime. 

♦ 

LIQUID FLUORINE. 

By C. F. TowxsENii, y.c.s. 

THE alchemists of the middle ages believed that 
somewhere in the universe was to be found an 
universal solvent, which would dissolve the most 
refractory substances as readily as water dissolves 
sugar. They named their solvent liquor alkahest, 
and what time they could spare from the search after the 
elixir of life and the philosopher's stone was spent in the 
endeavour to obtain it. Science has yet to prove, by the 
way, that there was not more method in the madness of 
the alchemists than is generally supposed, for in the 
remarkable substance, fluorine, chemists possess a material 
that approximates very closely to an universal solvent. 
Its chemical energy is so fierce that, except gold and 
platinum, nothing can resist it ; and even gold and platinum 
succumb to fluorine in time. The mere contact of most 
substances with fluorine is sufficient to cause, not mere 
solution, but light, flame, and fierce detonations. Dull, 
inert flint takes fire when exposed to fluorine vapour and 
becomes a brilliant incandescent mass. Lampblack bursts 



32 



KNOWLEDGE. 



[Februaby 1, 1898. 



into (lame, whilst charcoal burns with bright scintillations. 
Only the diamond is able to resist this powerful solvent, to 
which it does not succumb even at high temperatures. 
The similar element, silicon, which can be obtained in a 
crystalline form closely resembling the diamond, gives 
a magnificent display in the presence of fluorine, the 
crystals becoming white-hot and throwing showers of fiery 
spangles in all directions. The heat is so intense that the 
crystals melt, showing that their temperature has reached 
one thousand two hundred degrees Centigrade. Phos- 
phorus combines fiercely with fluorine. Prussian blue, on 
account of the cyanogen it contains, burns with a beautiful 
pink flame ; whilst from a crystal of iodine placed in 
fluorine vapour a heavy liquid distils with a pale flame. 
This liquid— an iodide of fluorine — etches glass, and if 
thrown into water hisses like hot iron. The last-named 
metal becomes white hot when exposed to fluorine ; even 
iron-rust behaves in a similar manner. Nearly all 
metals are raised to vivid incandescence in a current 
of the gas, many appearing very beautiful, especially 
aluminium and zinc. If the latter be slightly warmed 
it bursts into a white flame too dazzling to gaze at or 
describe. 

Although it has been known in various states of com- 
bination for many years, having been first discovered by 
Schwankhardt, of Nuremburg, in 1670, and rediscovered 
by Scheele in 1771, fluorine was not obtained as fluorine 
in the free state until about six years ago, when the French 
chemist, Moissan, succeeded in isolating it by employing a 
current of electricity from twenty-six or twenty-eight 
Bunsen batteries. The current was passed through the 
compound of fluorine and hydrogen known as hydro- 
fluoric acid, which is similar to hydrochloric acid. To 
improve the conductivity of the hydrofluoric acid it was 
necessary to dissolve another fluorine compound in the 
liquid. As will readily be imagined, it is not so difticult 
to obtain free fluorine as to keep it when obtained. Every 
part of the apparatus used by M. Moissan was made 
of platinum, with screw joints and washers of lead, 
which swell on contact with fluorine ; all the stoppers 
being of fluor-spar. Fluorine has a powerful affinity for 
silicon, one of the principal constituents of glass, so that 
it was impossible to use glass vessels or tubes to contain 
the gas. 

As regards the chemical nature of fluorine, it is a gas at 
ordinary temperatures, and is the lightest member of the 
series of elements containing chlorine, bromine, and 
iodine. The attraction of fluorine for hydrogen exceeds 
that of chlorine, and is so great that if a slow current of 
fluorine gas be passed into a tube of fluor-spar containing 
a drop of water, a dark fog is produced, which changes 
presently to a blue vapour consisting of ozone— the con- 
densed form of oxygen. The last-named substance appears 
to be one of the few materials which has no affinity for 
fluorine ; nothing is observed to take place between them 
even when they are heated up to one thousand degrees 
Fahrenheit. 

So far all experiments had been conducted with fluorine 
gas, which, at the time it was isolated, resisted all attempts 
to reduce it to the liquid state. Six years ago, however, 
there was no laboratory — such as that at the Royal Insti- 
tution — having powerful machinery for producing liquid 
air or liquid oxygen, at the command of the investigator ; 
in fact, liquid air itself was practically unknown. By the 
aid of this weapon. Professors Dewar and Moissan have 
succeeded in liquefying fluorine. At the extremely low 
temperature of liquid oxygen it was found that fluorine 
did not attack glass, and it was possible to use glass 
vessels to hold the newly liquefied element. The appa- 




ratus consisted of a small glass bulb, E, fused to a 
platinum tube. A, which contained another similar smaller 
tube, D. Elach of the platinum inlet and outlet tubes, 
B and C, was fitted with a screw valve, so arranged that at 
any moment communication could be cut ofi', either with 
the outer air or with the current of fluorine. The whole 
of the little apparatus was placed in a cylindrical glass 
vacuum vessel (not shown in the figure) containing liquid 
oxygen, and connected with a vacuum pump and a mano- 
meter. On entering, the fluorine gas passed into the 
annular space and then down the tube, D, into the glass 
bulb. At the temperature of boiling liquid oxygen 
( - 180° C.) the gas passed right through the apparatus, 
but without attacking the glass. As 
soon as the air pump was worked and 
the liquid oxygen boiled vigorously, 
a yellow mobile liquid — fluorine — was 
seen condensing in the bulb. 

Although at this very low tempera- 
ture ( - 185° C.) silicon, boron, carbon, 
sulphur, phosphorus, and iron, pre- 
viously cooled in liquid oxygen and 
placed in the liquid fluorine, remained 
unattacked, a fragment of frozen ben- 
zene or oil of turpentine was acted 
upon with great vigour, accompanied 
by incandescence, showing that the 
great affinity of fluorine for hydrogen 
stUl remained. 

Professors Moissan and Dewar 
noticed that if the liquid fluorine came 
into contact with liquid oxygen two 
layers were formed, the fluorine being 
at the bottom. If the oxygen was not 
quite dry they found that a white 
iiocculent precipitate, which they be- 
lieve to be an hydrate of fluorine, fell 
to the bottom. This could be filtered 
oti', and detonated violently as soon as 
the temperature rose. 

From the experiments it was foimd 
that the boiling point of fluorine is very SopieY,,.) 
close to —187^0., being identical with 
the boiling point of argon. This appears to be the first 
example of two gaseous elements boiling at the same 
temperature. 

By boiling the liquid oxygen surrounding the fluorine 
at a very low pressure by the help of an air pump, the 
temperature was lowered to -210° C, but the fluorine 
showed no signs of solidifying. Nevertheless Moissan and 
Dewar hope to produce a still lower temperature by 
causing the liquid fluorine itself to boil vigorously at a low 
pressure. 

The specific gravity of liquid fluorine was determined 
by dropping in small pieces of solid bodies, including 
wood, caoutchouc, etc., previously cooled in Uquid 
oxygen. It was found that amber rose and fell in the 
Uquid, so that the specific gravity of the liquid fluorine 
must be about the same as that of amber, namely, 
1-14. No specific absorption bands were visible in the 
spectroscope. 

These experiments, which are more than interesting, 
seem to show that there is no limit to the knowledge (of 
the material universe at all events) that mankind may hope 
to secure by patience and increase in mechanical skill, for 
the work just described has been carried on within sixty- 
three degrees of absolute zero, where, if our present 
knowledge is of any worth, the life of the universe itself 
would be extinguished. 




Apparatui- for Lique- 
I'aitioii of Fluorine. 
I From the Proceed- 
in(/s of the Chemical 



February 1, 1898.; 



KNOWLEDGE. 



33 



%ttttxs. 



[The Editors do not hold themaelTes reaponsible for the opinions or 
statements of correspondents.] 

IS WKATHER AFFKCTKD UV THK MOON :- 
To the Editors of Knowledge. 
Sirs, — I Lave been reading with much interest the 
article with the above title by Mr. A. B. MacDowall, M.A. 
There is one diliiculty in connecting the barometric curves 
with the moon's age and position which he appears to have 
overlooked. It is this. His map of the curves is for 
London, but taking the meridian of London, and proceeding 
north or south, the pressure varies greatly on the same day. 
Thus there may be very high readings in London, whilst 
very low ones prevail over Scotland and the South of 
France, or vice versa, according to the position of anti- 
cyclones or storm centres. 

The same may be said regarding places having the same 
latitude. Storms cross the Atlantic in about a week, 
though they vary much in their rate of progress and the 
direction in which the centre of the cyclone advances. 
May not this be influenced by the increase or decrease of 
the moon's declination ? If this is so, it would help to 
explain much which is obscure in the way the moon affects 
the weather. 

Near the Equator one would expect to find evidence of 
any change of pressure caused by the moon's attraction, 
as twice monthly it passes directly over those regions. 
This, however, does not seem to be the case. In Southern 
India the barometer readings scarcely vary for months, 
excepting the daily tides, and a slight fall during the south- 
west monsoon. 

The spread of this monsoon and the rainfall which 
accompanies it in Northern India has, I believe, been 
supposed to be affected by the moon's action, but I do not 
know on what data. During the monsoon there are 
usually breaks at intervals of about a fortnight, which 
would tend to support that theory. L. Paxton. 

Lavant, Chichester. 

[I did not overlook the point raised as a difficulty by 
Colonel Paxton. While I rather think the smoothed 
Greenwich curve might be taken as fairly representative 
for a considerable region (perhaps the greater part of these 
islands), I should not be surprised to find at some more 
distant stations either (1) an equally good correspondence, 
but with the waves retarded or advanced somewhat, or even 
opposite in phase to the Greenwich waves ; or (2) a corre- 
spondence imperfect or obscured, or no proper corre- 
spondence at all. In the former case the evidence of 
lunar influence would, I consider, be strengthened, and 
in the latter I do not see that it need be seriously shaken. 
In a science so little advanced as meteorology, and dealing 
with such a " complex " of natural causes, we should be 
extremely chary, I think, about asserting what should or 
should not happen in this place or that on the hypothesis 
of some influence of astronomical nature. Our business 
as students of natural law is primarily with facts, and the 
interpretation of facts. And in the weather of any region, 
it seems to me, we may find so large an amount of regular 
correspondence with some astronomical cycle (that of the 
moon, e.f/.), that it becomes more difficult to think all this 
agreement purely fortuitous than to believe there is a 
causal nexus between the phenomena. I do not assert 
it is so in the present case, though I may be inclined to 
hold it as a " pious opinion." If we find a good corre- 
spondence in one region and not in another, may there 
not be something in the peculiar position of the former 
region which tends to render the supposed influence 



apparent ? And, similarly, if we find a good corre- 
spondence in certain years and not in others, may we not 
find this due to something special in the relative positions 
of the moon and the earth in the former case ? Colonel 
Paxton's suggestion that the path of depressions may be 
influenced by the moon's declination seems to be well 
worth consideration. — Alex. B. MacDow.u.l.1 



To the Editors of Knowledge. 
Sirs, — With reference to the article in your issue for 
January this year, entitled "Is Weather afl'ected by the 
Moon ? " may I be permitted to make a few remarks ? As 
the writer states, the periods of concurrence between the 
barometrical curves and the various phases of the moon 
are irregular ; or, to put it otherwise, he sometimes 
observes that they coincide. Si post hoc, non enjo prapter 
hoc, is an excellent maxim in meteorology, as in other 
things. R. A. Proctor, in an essay called " Sunspot, 
Storm, and Famine," says as follows : " That for countless 
ages the moon should have been regarded as the great 
weather-breeder, shows only how prone men are to recog- 
nize in apparent changes the true cause of real changes, 
and how slight the evidence is upon which they will 
base laws of association which have no real foundation m 
fact. . . . And as the weather is always changing, even as 
the moon is always changing, it must needs happen that 
from time to time changes of the weather so closely follow 
on changes in the moon as to suggest that the two orders 
of changes stand to each other in the relation of cause and 
effect. Thus rough rules came to be formed ; and as (to 
use Bacon's expression) ' men mark when such rules hit, 
and never mark when they miss,' a system of weather-lore 
gradually comes into being which, while in one sense 
based on facts, has not in reality a particle of true 
evidence in its favour — every single fact noted for each 
relation having been contradicted by several unnoted facts 
opposed to the relation." 

Furthermore, I would like to know if pressure alone 
constitutes weather ? G. E. E. 

January 16th, 1898. 

[While it is well to remind ourselves of the tendency 
above spoken of, the applicability of Proctor's remarks to 
the present case may fairly, I think, be doubted. We 
have to account for a barometric rhythm (similar to the 
lunar), persisting for the greater part of a year at one time. 
I have not represented that " pressure alone constitutes 
weather." — Alex. B. MacDow.\ll.1 



VEaETATIOiV OP AUSTRALASIA. 
To the Editors of Knowledge. 
Sirs, — It is with some diffidence that I again venture 
to trespass upon your valuable space, but I can hardly 
allow Mr. W. B. Hemsley's remarks upon my letter in the 
September issue of Knowledge to pass unchallenged. It 
seems absurd to me — as it must also to anyone who read 
Mr. Hemsley's article in the May issue of this journal — 
that he should deny having written the statement I attri- 
buted to him, and accuses me of not having read the 
opening sentence carefully. In this Mr. Hemsley errs, 
for I read and re-read it, as I could scarcely credit my 
senses after a first perusal that a botanist of Mr. Hemsley's 
world wide reputation could be guilty of such a misstate- 
ment. Mr. Hemsley twits me with making a general 
statement re the genus Ficus, and characterizes it as mis- 
leading ; it would have been an easy matter to have cited 
the forty species of this genus, but cui bono ? If I may 
make the retort, Mr. Hemsley is still more misleading in 
his statements. " The Vegetation of Australasia " is the 
subject of his paper. Queensland forms a large part of 



34 



KNOWLEDGE 



[Febbuaky 1, 1898, 



Australia, and Mr. Hemsley now acknowledges that it is 
much richer in useful plants, and especially in plants 
yielding edible fruits, than any other part of Australia. 
Mr. Bailey (and who knows better '?) says that Queensland 
is especially rich in plants of economic value ; therefore 
Mr. Hemsley's general statement that " Australia contains 
comparatively few plant.s yielding products ol economic 
value" is misleading on the face of it. It is very like 
begging the question to say that Queensland contains a 
relatively large Asiatic element, as distinguished from the 
characteristic Australian vegetation ; this is not the point 
at all. The plants are in Australia and form part of its flora ; 
their origin in this case matters not. In conclusion I 
trust Mr. Ifemsley will not think I am playing the part of 
a carping critic, but I must join issue with him once more. 
Ilie statement that " the aborigines use the bark thnnm nff" 
from gum trees, etc., for shelter (mitr, p. 102), is incorrect. 
The bark thus shed or thrown off is utterly useless for 
the purpose assigned to it by Mr. Hemsley, being too 
brittle, very thin, crumbling almost to the touch, curled 
up by the sun, and only shed in pieces absolutely too small 
for any practical purpose whatever. The bark used by 
the aborigines, and by many colonists at the present time, 
is the true cortex, stripped from the tree by human agency — 
not nature's. Diagonal cuts are made round the circum- 
ference of a tree about a foot or so from its base, and 
another series of cuts, also round the circumference, about 
six to eight feet from those below ; an incision is then 
made down the length oi' the trunk, the bark is tapped 
gently with an axe on the severed part, and, if the sap is 
well up, the result is a broad strong sheet of bark peeled 
right off from round the trunk. Needless to say, this 
operation kills the tree. I forgot to mention that Mr. 
Bailey is indeed surprised to hear that the produce of the 
plants named is known to commerce, and would be pleased 
to have more information on the point. 

Taringa, viu Brisbane, Fred. Whitteron. 

Queensland, 29th October, 1897. 

[As Mr. Whitteron has renewed his accusation that I 
had stated that " the flora of Australia contains compara- 
tively few plants yielding products of economic value," I 
will repeat here the opening sentences of my article 
(Kno^t:,edge, May, 1897, p. 118), which to my mind convey 
a very different meaning from that portion of a sentence 
he-quoted in his first letter (September, p. 212) : — " The 
popular impression respectmg the Australian flora is that 
it contains comparatively few plants yielding products of 
economic value, and this is a correct impression so far as 
edible fi-uits and vegetables are concerned ; but it should 
be remembered that this is true of most countries. Fruits 
and vegetables that come to our tables are the result of long 
generations of cultivation. Take the crab, carrot, parsnip, 
celery, or almost any of our fruits or vegetables in a wild 
state, and we should get very little satisfaction out of 
them. This, however, is a little digression. Australia is 
by no means poor in vegetable products, and other 
countries have been greatly enriched by importing and 
cultivating some of them." 

I maintain that the foregoing sentences fairly express 
the actual facts, and that Mr. Whitteron's wild fruits, with 
few exceptions, would only be eaten by aborigines or 
persons in extremities. Returning to the forty species of 
Ficus or fig : Mr. Maiden, in his " Useful Native Plants of 
Australia," enumerates only three species, two of which 
he says are used as food by the aborigines ; and of the 
third he cites a traveller who pronounced the fruit " very 
good," and a writer who states that the fruit is not 
edible ; adding himself that the appetites of explorers 
frequently become voracious and not too discriminating. 



I do not pretend that Mr. Maiden's book is complete and 
perfect, and I think it is very probable that there are better 
figs than he was aware of when he wrote. To give another 
example. In Sir Joseph Banks's recently published 
" Journal," p. 299, is the following passage : — " AVe had 
still fewer fruits ; to the southward was one resembling a 
heart cherry {Ewienia), only the stone was soft. It had 
nothing but a slight acid to recommend it. To the north 
ward we had a kind of very indifferent fig ; a fruit 
we called plums, and another much like a damson, both in 
appearance and taste. Both these last, however, were so 
full of a large stone, that eating them was but an unprofit- 
able business. AVild plantains we had also, but so full of 
seeds that they had little or no pulp." 

Here, again, I do not assume that Sir Joseph Banks and 
his party, with all their knowledge and much as they 
needed such things, found all or the best the country 
yielded ; but who has read the narratives of the many 
subsequent explorers in the same and different districts 
knows how little they found that served to keep body 
and soul together. Therefore I think the general and 
qualified manner in which I wrote is fully justified by the 
facts. — W. BoTTiNG Hemsley.] 



EGG t'OLLKCTING IX IT.S RELATIOX TO SCIEXCE 
To the Editors of Knowledge. 

Sirs, — In connection with Mr. Field's article in your 
December issue under the above title, I beg to ask the 
following questions: — (1) Why a light-coloured egg so 
persistently appears in the clutches of the eggs of some 
birds and very rarely or never in others ? (i) Why are 
the eggs of some birds coloured at or around the smaller 
end, whilst those of others are scarcely ever so coloured ".' 
Never having accepted the theory that when a light- 
coloured egg appears in a clutch it is owing to exhaustion 
of the pigment, I paid considerable attention to this subject 
in the spring of 1889, taking the blackbird into my con- 
fidence. 

The following observations, I think, clearly demonstrate 
that the exhaustion theory cannot be supported by facts: — 

Marih 19tli.— Eggs, four ; all light in colour ; first and third the 
lightest ; all infertile. 

March 25th. — Eggs, four; three dark eggs, one light. This brood 
died in the nest, probably from the cold. One infertile egg. 

Slareh 25th. — Eggs, three; the first the lightest coloured egg. All 
these were fertile. 

April 15th. — Eggs, fi^e ; four eggs of the normal colour, one xery 
light. 

April 15th. — Eggs, five; three dark, two light. In this clutch the 
lightest coloured eggs weighed one hundred and twenty grains each, 
the dark ones one hundred and eighteen grains each. 

April 20th. — Eggs, three; one egg light in colour; all fertile. 

April 20th. — Eggs, five ; tliree dark, two very light. 

April 20th. — Eggs, four ; three dark, one light. 

April 22nd. — Eggs, three .- second egg laid the lightest. 

April 24th. — Eggs, four ; first and fourth light eggs. , 

April 28th. — Eggs, four ; first and fourth light eggs. 

May 6th. — Eggsj four; the three first laid light in colour, the 
fourth darker and very much flecked; this egg infertile. 

May 13th. — Eggs, six. In this clutch the fii'st four were typical 
eggs of the blackbird; the fifth egg very light in colour; the sixth 
egg dark, and very much coloured at the small end. These eggs were 
all fertile excepting the fourth, which showed no signs of fertility. 
This clutch was laid by the same bird, and iu the same nest, as the 
clutch dated March 25th. 

The litflit-colmired eggs arc, as a rule, a few grains heavier than 
the dark, and a dark egg often followed a warm moist day. 

Again, in 1890, 1 watched a nest from day to day and 
obtained a clutch of five eggs — which I have before me. 
The first four laid are typical eggs of this bird, but the 
fifth — the last laid — has a beautiful pale green ground, 
with flecks and blotches of rich brown. This clutch would 
be considered by the votaries of the exhaustion theory as a 



Februaky 1, 1898.] 



KNOWLEDGE 



35 



fine illustration of their theory ; but inasmuch as the flecks 
and blotches are numerous on the pale egg, there must be 
as much colouring matter on it aa on any of the others. 

The smaller end marking of eggs is a physiological 
enigma well worthy of the attention of oologists. This 
departure from the usual larger end marking is much 
more frequent among the eggs of the I'alcuniihi- and the 
Corviiiiv than among those of any other birds ; and in 
looking through a series of twenty clutches of the sparrow- 
hawk — now before me — I see thirty per cent, of the eggs 
exhibit this peculiarity. Then, on the other hand, the sis 
hundred clutches of the common house sparrow I have 
in my cabinet, exhibit less than a dozen examples. 

Another question may be asked. Why do two birds of 
the same genus, namely, the corn bunting and the 
yellow bunting, oppose and support this style of colora- 
tion ■' I have a very long series of the clutches of both 
birds before me. In the former there are a very few 
examples of smaller end marking, whilst in the latter there 
is a large percentage ; and in some of the clutches all the 
eggs have a circlet of fine lines around the smaller ends, 
leaving the crown quite bald. 

I dare not trespass further upon your space beyond 
expressing a hope that some of the scientific contributors 
to your journal may write more fully upon this subject. 

Koyston, Herts. Joseph P. Nunn. 

A BRILLIANT METEOE. 
To the Editors of Knowledge. 

Sirs, — It may interest you to know that an unusually 
brilliant meteor was observed from here in dnyliijht at 
5h. 7m. o'clock, Dublin time, this afternoon. It was seen 
by several persons. My companion and I saw it first 
about E.S.E., at a low altitude, perhaps twelve or thirteen 
degrees above the horizon. It appeared to travel .slowly 
across the sky in an almost horizontal line, slightly 
inclining earthwards, and disappeared behind a cloud and 
the hills to the S.E. 

The nucleus was very brilliant and large, and was 
surrounded by a glowing greenish colour ; the tail tapered 
to a point, and was pink along the margins and glowing 
pale green on the central line. My companion describes 
the colour as sparkling green. Another observer at a 
distance from us (of five hundred yards or so) also observed 
the green colour. Our point of observation was about 
forty feet above mean sea-level ; our view eastwards down 
the valley was unobstructed. Across the river to the S.E. 
hills rise about five hundred feet high, and over these 
some clouds rested ; otherwise the sky was clear, act! there 
was ijiioil daylight. No noise was heard. The wind was 
about S.W. and hght ; thermometer 52". 

Carrick-on-Suir, J. Ernest Grubb. 

Jan. 21, 1898. 

DISSOCIATION OF THE ELEMENTS. 
To the Editors of Kxowledge. 

Sirs, — Dr. Emmens, of New York, has just published a 
book in which he says that he has obtained a new 
substance from iron and nickel, and the same substance 
also from cobalt. He also says that he has converted 
silver into a substance that cannot be distinguished from 
gold and which appears to he gold. Is not this an 
argument in favour of Sir Norman Lockyer's theory 
with regard to the pre-nebular condition of matter ? He 
describes it as being matter too tine to receive a chemical 
name, which curdles and produces H. or something allied 
to H. Further curdling goes on and the dust of Mg., 



C, O., Fe., Si., and S. is produced, etc., from which I 
infer that he considers all the so-called elements to be 
derived from one kind of matter. If the same substance 
can be obtained from Fe. and Ni., and also Co., does it 
not appear as if these so-called elements are derived from 
one and the same kind of matter, or that they are 
compounds "? — which latter is improbable. 

Again, if one element can be converted into another, 
does it not seem probable that each so-called element had 
one and the same origin ? Of course, we know that An. 
and Ag. belong to the same group of elements, also Co., 
F., and Xi. ; but might not this grouping of the so-called 
elements point to the same conclusion that they have been 
buUt up from the same kind of matter ? Might it not 
also be possible on further investigation to find relations 
which have not yet been recognized between the diS"erent 
groups of the so-called elements ! It appears to me that 
there is a law, as yet not recognized by chemists, having 
some connection with temperature, in accordance with 
which law these so-called elements are built up from one 
and the same kind of matter. W. H. Cook. 



THE BRITISH TRAP.DOOR SPIDER. 
To the Editors of Knowledge. 

SiBs, — In connection with the extremely interesting life 
history of Ati/pus piceiis sul:., the so-called trap-door spider 
of Britain, by Mr. Fred. Enock, in your November and 
December, 1897, issues, it may interest some of your 
readers to know that the Hastings colony is no longer 
nameless from the want of a mature male. On 
October 17th, 1897, I accidentally discovered the colony, 
and on the 31st obtained a mature pair, since determined 
by the Eev. O. Pickard-Cambridge to be Atypu.s piceu.i 
suh., the same unfortunately as all the other known 
colonies in Britain. I have since found several strong 
colonies in this district, widely distributed, but all 
A, picetis. 

52, Tackleway, Hastings. H. G. Jefferv. 



THE URANIA STERNWARTE. 
To the Editors of Knowledge. 

Sirs, — I think the following extract wUI be of some in- 
terest to those of your readers who desire to see established, 
either in the metropolis or in some other large town of 
England, a liimilar institution to that now existing at 
Berlin, vir.., the Urania Sternwarte, an institution referred 
to in Knowledge for September, 1897. I may add that 
I came across this extract quite accidentally, shortly 
after reading Mr. Lavalette's letter on this subject in 
Kno\^xedge for August, 1897. 

The following is the extract, which was in the Penny 
^[a^|f1zinc for September 25th, 1833. 

'•PrBLlc Obsehtatort. — A correspondeut, who signs himself 'A 
Man of Kent,' says ; ' Last week, for a shilling, I was able to make 
acquaintance with an aquatic world whose existence I, till then, had 
never been aware of. The "hydro-oxTgen microscope " convinced me 
that a dewdrop may be as full of moving beings as Almack's. But I have 
been ail my life, or half my life — that is, all the nights of it — desiring 
a nearer acquaintance with the stars ; and I wish that my honest 
shiDing C3ultl procure me admission to some observatory, where I 
could contemplate those enormous evidences of the Creator's power 
with as much ease as I did the minute atoms whose existence I had 
never known of before.' The hint appears to us well worthy the 
attention of those who have capital and enterprise. We have little 
doubt that the prevailing desire for knowledge would render a cheap 
observatory one of the most attractive objects in the metropolis." 

If, sixty-four years ago, such an opinion was expressed, 
bow much more now is there need for such an observatory ! 
Ivo F. H. Cabr-Gregg. 



36 



KNOWLEDGE 



[Februaet 1, 1898. 



BRITISH 



,# 




ORNITHOLOGICAL 



NOTES, 



Conducted by Harry F. Witherbt, f.z.s., M.B.o.n. 

WiGEON NESTING IN YORKSHIRE. — Od May 12th, 1897, 
whilst on a birdnesting expedition in a locality not very 
far from Scarborough which is largely frequented by water- 
fowl, I flushed a duck from the ground. A short search 
sufficed to find the nest — not very carefully concealed 
amongst some nettles at the foot of a small birch tree. 
The nest consisted of a hollow in the ground, thickly lined 
with down from the parent's body, mixed with small pieces 
of dead nettle stems and dry grass, these latter materials 
being sparingly used, and conveying the impression that 
their presence was more or less accidental. The nest con- 
tained nine cream - coloured eggs, which I immediately 
imagined could be no other than Wigeon's ; but, being under 
the impression that this bird did not breed in England, I 
dismissed the idea as preposterous. As, however, if not 
a Wigeon's, I could not determine the species to which the 
nest belonged, I concealed myself, and after a short wait 
had the pleasure of seeing the parent return, accompanied 
by the male bird, and was able to see, beyond any doubt, 
that they were Wigeon. My delight at this unexpected 
verification of my surmise only an ardent ornithologist 
can conceive, and I lost no time in getting the camera to 
work, the result being two pictures — one of which is here 
reproduced. On .June 2nd I was fortunate enough to find a 



. I ''^■'i. 




■»-' 


x .^ 




• *•:•• ■* 






' V: 


1 * K " " 






^^ 


SViff^PfiA 


flfs ^S^ ^ ^ i^^^ft9 


WSk 


t<-y^T^5|b 


p^'^'-^yiRnB 


H 


Pi 


k^^l 


■H 


K^« 


%,„^JS^tmM. ,.«5fci;* 



second nest of the same species, containing nine younc 
ones, near the same place. As the locality was not far 
from the private lake of a gentleman who keeps a large 
number of waterfowl of various species, I took the first 
opportunity of inquiring if there was any probability of the 
parents having strayed from his place ; and was informed 



that although his birds were pinioned, frequently their 
progeny escaped in the spring, and that, very possibly, 
those I had found were some of the home-bred birds. At 
the same time, during the winter months, the lake and 
adjacent river are %isited by very large numbers of perfectly 
wild birds, most of which leave in the spring ; but it is 
possible that one or two pairs, attracted by their pinioned 
companions, suitable surroundings, freedom from molesta- 
tion, and a plentiful food supply, may have stayed to 
breed. — Wm. J. Clarke, Scarborough. 

[The Wigeon breeds in the North of Scotland, and in a 
few places in Ireland, but it has never yet been known to 
breed in a wild state in England. Mr. Clarke's note is of 
great interest, since it proves that the nest of this bird 
may now be looked out for in England, with a fair possi- 
bility of success. It is unfortunate that semi-domesticated 
birds were in the vicinity ; and taking this into considera- 
tion, it is impossible to accept these birds as truly wild 
ones, and, on this evidence, to add the Wigeon to the birds 
which breed in England. — H. F. W.] 

Hoopoe in Sdssex. — An immature female Hoopoe was 
shot in the Paternoster Wood, Hartfield, Sussex, on 
December 14th. I cannot find that one has ever been 
recorded so late in the year before ; and as they have been 
known to breed in the southern counties, is it possible the 
bird is a native and not a migrant '? — Emma L. Turneb, 
December 25th, 1897. 

[The Hoopoe occasionally visits us in winter. If the 
Hoopoe were not so persistently persecuted it would, 
without doubt, become a regular breeding species in 
England ; but it is never likely to stay here during the 
winter.— H. F. W.] 

Early Nesting of Birds. — An interesting effect of the 
continued mildness of the weather this season has been the 
extraordinary fact that several birds have been observed 
with nests and eggs in December. In the FieW we find 
records of Wild Ducks with nests and eggs in the middle of 
December, and a Robin with a nest and egg on Decem- 
ber 16th. 

On Si/brids between the Capercailye and the Pheasant. By W. 
Eagle Clarke [The Annals of Scottish Xfatural llUtory. .Tanuary, 
1898, pp. 17-21 ). — The fourth example of this curious livbrid is here 
recorded and described. The bird, which is a male, was obtained in 
September last at StronchuUin, Blairmore, south-east Argyllshire, 
where it had been observed for eighteen months, and was sent to Mr. 
Ilarvie-Brown by Mr. G. H. Black. The author also describes and 
ijives the history of the other three examples known to science. 

Rose-coloured Pastor in West Soss-shire {Annals of Scottish 
Xntiiral Historii, January, 1898, p. 49). — A bird of this species is 
ii'corded by J. A. Fowler as having been obtained on August 16th, 
1 !S97, at Inverbroom. 

Sabine's Oull in Arran (Annals of Scottish Natural Histori/, 
•Tanuary, 1898, p. 52). — John Pat.erson records the capture of an 
immature specimen of this bird on the shore at Sliddery, Arran, on 
September 22nd, 1897. 

Montai/u's Harrier breeding in Ireland. — CoEBECTlON. (The 
Zoologist, January 15th, 1898, p. 24.)— Mr. John H. Teesdale, 
who reported the shooting of a specimen of this bird from a party of 
six in County Kerry (see Knowledge, November, 1897, p. 257), now 
writes to The Zoolo(,ist that, after further examination, Dr. Sharpe 
has pronounced the bird to be a young male of the Hen Harrier. 

Pectoral Sandpiper in Norfolk-. {The Zoologist, January, 1898, 
p. 25.) — An adult female of this species is recorded by J. L. 
Xewiuan as having been procured on Breydon, Norfolk, on August 
iNth, 1897. 

The Red-crested Pochard (Fuligiila rufina) in Westmoreland {Ibis, 
January, 1898, p. 176). — The Rev. H. A. Macpherson wi-itos that an 
immature male of this species was shot in a small tarn in the neigh- 
bourliood of Haweswater, Westmoreland, on the 9th of October. 1897. 

All contribiUions to the column, either in the way of notes 
or photographs, should be forwarded to Hakry F. Witelkrby, 
at 1, Eliot Place, Blachheath, Kent. 

Note. — The first issue of Knowledge containing British Ornitho- 
logical Notes was that for October, 1897. 



February 1, 1898.] 



KNOWLEDGE 



37 



A PORTION of a roadway, believed to' be of Roman origin, 
has recently been discovered at Reigate. The path — 
fourteen feet wide, and five feet below the surface — is com- 
posed of flints, the edges of which have been trimmed to fit, 
and is altogether of a very even character. By some local 
arohiEologists the path is considered to be a continuation 
of the noted Pilgrims' Way to Canterbury Cathedral, which 
passes through the town of Eeigate ; while others contend 
that it formed part of the old Roman road from Winchester 
to London. — -_ — 

The Council of the Royal Astronomical Society have 
awarded the Gold Medal of the Society for this year to 
Mr. W. F. Denning, " for his meteoric observations, his 
cometary discoveries, and other astronomical work." The 
medal will be given to Mr. Denning at the annual general 
meeting of the Society next month. 



Noti»0 of iSooits. 



The Geological Society s medals and funds this year are 
awarded as follows ; — The Wollaston medal to Prof. 
F. Zirkel, the Murchison medal and part of the fund to 
Mr. T. F. Jamieson, the Lyell medal and part of the fund 
to Dr. W. Waagen, the balance of the Wollaston fund to 
Mr. E. J. Garwood, the balance of the Murchison fund to 
Miss J. Donald, the balance of the Lyell fund to Mr. Henry 
Woods and Mr. W. H. Shrubsole, and a part of the balance 
of the Barlow- Jameson fund to Mr. E. Greenly. 



The want of an independent water supply has long been 
felt at the Zoological Gardens, and recently it was decided 
to put down an artesian bored tube well. The results have 
been, as was anticipated, the tapping of powerful springs 
of pure water in the chalk, at the depth of four hundred 
and fifty feet, yielding two hundred and forty thousand 
gallons per day. — 

Sir William Gowers, f.r.s., is one of a very few who 
can trace their success in the world to the accidental 
influence of shorthand. It was his skill in this art which 
determined that he should stay in London instead of going 
into an obscure practice at Bournemouth ; it was shorthand 
which gave him the post of secretary to Sir William 
Jenner. Those who have been influenced by his books 
should know that they owe to shorthand every word of 
them — not one of them would have been written had Sir 
William been ignorant of shorthand. He contends that 
that which is secured by the use of shorthand, even at a 
low speed, is this : in a given time there can be twice the 
amount of record that is possible with longhand, and yet 
twice the time in which to observe ; and thus transient 
phenomena can be adequately described which would elude 
entirely the slow pursuit of longhand. Without the use of 
writing the facts that pass before him will leave only 
transient furrows on the sands of unaided memory, 
vanishing for the most part when new facts disturb the 
surface ; and only immediate record can preserve from these 
dangers the personal science on which depends the work 
of those who apply their knowledge to the welfare of the 
race. It is a prevalent idea that shorthand can be written 
but cannot be read. On this head Sir William says : 
" The popular error that it is illegible is due to the immense 
number of shorthand writers who learn only to write and 
to immediately transcribe, and who have taken no pains 
to secure the ability to read. Because reading is not a 
spontaneous result of writing, it is assumed to be im- 
possible. The ability to read shorthand can indeed be 
acquired perfectly without any ability to write it, and is 
sometimes acquired." 



LUjht, Visihle awl Invisible. By Silvanug P. Thompson, 
D.sc, k.r.s. Illustrated. (Macmillan & Co.) Gs. net. 
There can only be one opinion upon this book, and that 
opinion is that the book is excellent in every respect. A 
course of Christmas lectures at the Royal Institution has to 
fulfil several conditions, chief among which are : language 
simple enough to be understood by people who are not en- 
gaged in scientific work, experiments numerous and striking, 
and attention to recent work of importance. Given these 
conditions and a capable lecturer, and you evidently have 
the material to construct a work of science at once popular 
and authoritative. Prof. Silvanus Thompson's book had 
such an origin, and we have no hesitation in saying that 
it is one of the best works of its kind ever put before an 
intellectual public. The student of optics will learn more 
from it than from half a dozen examinational text-books ; 
the teacher will find inspiration for many instructive 
experiments ; and the general reader whose mind has not 
been vitiated by Indulging in a pabulum of scraps of science 
will find the whole book a source of mental pleasure. The 
general facts and print' iples of the science of liglit are first 
described, then the spectrum and the eye, and afterwards 
follow in succession chapters on polarization, the invisible 
spectrum (ultra-violet and infra-red parts), the invisible 
spectrum and Rontgen radiation. The treatment of polari- 
zation — a difficult subject to grasp thoroughly — is lucid in 
the highest degree. The illustrations rank among the best 
specimens of half-tone process work, and the whole volume 
is a delightful example of the way in which science should 
be presented to intelligent readers. 

Studies ill Psycliical Research. By Frank Podmore, m.a. 
(Kegan Paul & Co.) Before entering on a brief criticism 
of the contents of this book it is only fair to state that 
Mr, Podmore deals with his material in what, according 
to his Hght, is a perfectly impartial mind. His object 
throughout appears to be to get at the bottom of the 
subject, and he sifts the evidence on both sides. 

Faith — that's the word — and in it lies the explanation 
of most spiritualistic phenomena. But it is not given to 
all of us to see things with an eye of faith, or to be the 
fortunate percipients of any phenomena which cannot be 
explained by physical laws or be referred to a derangement 
of the mental faculties. Mr. Podmore shows that many 
of the 30-caUed spiritualistic manifestations are due to 
trickery. Upon a hardened physicist, who has never 
seen a ghost or heard noises which could not be accounted 
for physically, who has never been worried in a haunted 
house or deluded by theosophical revelations, Mr. Pod- 
more's narratives do not make the faintest impres- 
sion. We learn science through individual experience 
nowadays, and the results obtained can be tested by 
anyone who so desires. Is it any wonder, then, that 
when a set of phenomena which we cannot reproduce at 
will is brought before us, we are apt to regard it with 
incredulity ? 

A number of cases are given of visions received within a 
few hours of the death of the persons represented. With 
reference to aU of these we say that the evidence is in many 
cases very weak, and that the accounts of the visions were 
generally written after the event, whereas they should 
have been set down before. It is not following a scientific 
method to select cases when the visions have come true, 
and leave out of consideration those which have not. 
Very many people see visions and dream dreams and 
forget all about them ; and we venture to assert that the 
number of visions and dreams which go ixnfullilled far 
outweigh the few which are afterwards found to have 



38 



KNOWLEDGE. 



[Febecaby 1, 1898. 



some relation to subsequent events. With regard to cases 
of secondary consciousness, when two distinct individu- 
alities are represented in one person, they are due to 
mental aberration, and furnish subject for inquiry by 
students of neurology rather than by psychical researchers. 
Hallucinations of various kinds may also often be found to 
have their origin in disorders of the optic nerves. 

The Reliquary mid lUustrate/l ArchienhMjist. Vol. III. 
1897. (Bemrose.) 12s. net. Another annual volume 
of this luxurious quarterly has been forwarded to us. 
The illustrations, which constitute the principal attrac- 
tion, will afford an immense treat to those who delight 
in antiquarian research. A noteworthy feature is the 
inclusion of a plate depicting a corner of Chancery 
Lane as it appeared in the year 1798. We are informed 
that Isaac Walton lived in one of these houses from 1627 
to 1644. The frontispiece is a plate giving a presentment 
of His Satanic Majesty- -the Prince of Darkness — as he 
is represented at Notre Dame Cathedral, Paris. Other 
features are no less absorbing ; and. of course, the iUustra- 
tions are accompanied by articles written by experts on the 
several subjects, the whole forming a most artistic book. 

Problems of Xiitiire : I!eseiircliis ami Discoveries lii/ (riistar 
Jaeger, M.D. Edited and Translated by Henry G. 
Schlichter, d.sc. (Williams & Norgate.) This selection 
from the papers of Dr. Jaeger — better known by his 
hygienic clothinp; than for his scientific work — are worth 
publication. The papers cover a variety of subjects in 
zoology, physiology, anthropology, etc. ; and though they 
were first published between twenty and thirty years ago, 
many of the ideas contained in them have been justified 
by discoveries made since their appearance. The essays 
on Darwinian principles reveal a mind familiar with organic 
life in many aspects, and acute enough to solve some of 
the problems involved in it. They would have been given 
additional value if not only the date of publication, but 
the organ of publication, had been given at the head of 
each. 



SHORT NOTICES. 

Practical Physiology. By Alfred F. Blaisdell, M.D. (Ginn& Co.) 
Illustrated. 58.* Of all works on physiology that we have perused 
none seem to approach nearer to the ideal text-book than this one. 
Physiology as a science is usually taviglit in schools as a mere 
catalogue of (acts, and very little attention is, as a rule, devoted to its 
usefulness from the hygienic point of view. One may learn all about 
the heart, brain, and skeleton of the human body, and yet not be a bit 
wiser as to the way in wliicli diseases of the human subject may be 
combatted or prevented. Dr. Blaisdell steps into this breach, and 
supplies abundance of advice for every emergency. Numberless 
experiments are given, and chapters on accidents and first aids to 
injured persons are included. The illustrations, two hundred in 
number, are excellent. 

Reform of Chemiral and Physical Calculations. By C. J. T. 
Hanssen. (Spon.) Illustrated. One great drawback in the interest 
of chemists and physicists for the last hundred years has been the 
non-uniformity of the standards of calculations adopted by different 
nationalities. An attempt is here made to minimize tliis confusion 
by adopting a method of calculation which avoids long rows of 
decimal fractions — rliscordaut values attributable to the variation of 
the acceleration of gravity in different latitudes. The idea is to 
establish a chemical and physical observatory on the west coast of 
Italy, and to take as standards the results of observations made 
there. The international weight of oxvgen— a cubic metre of which 
weighs, at lat. 45°, 1-429U9 k^'., and at lat. 52'', 1-4,3003 kg.— at this 
place comes out to a very simple figure ; and as hydrogen is proposed 
to be the unit adopted, the exact weight of one cubic metre can be 
ascertained. The author calls places of the same latitude the "circle 
of international gravity," which will be to chemists and physicists what 
Greenwich is to astronomers. 

The Story of Germ Life— Bacteria. By H. W. Conn. (Newnes.) 
Illustrated. Is. We have already noticed other books in this handy 
series, and this one in particular is welcome, as it deals with an im- 
portant branch of modem medicine. It aims at imparting a clear 
and popular account of these low forms of life, and, as the author 



remarks in his preface, to enlighten tlie public as to their power of 
doing good and bad service to mankind. For example, it may interest 
consumers of the fragrant weed to krow that the different flavours 
of the various grades of tobacco are probably due to fermentation set 
up in the curing process by different kinds of bacteria. The inclusion 
of more illustrations would have enhanced the attractiveness of the 
book. 

We have received a copy of the Thomton-Pickard 1 898 catalogue. 
This issue is in no way inferior to previous ones, either in the way m 
which it is " got up," or in the value and novelty of the matter which 
it contains. We especially note particulars of a new shutter at a 
cheaper i-ate than hitherto, and a five-by-four Amber camera. We 
doubt not that these instruments will maintain the high standard of 
excellence set up by this firm. 

BOOKS RECEIVED. 

Photo-aquatint and Photograriire. Bv Tliomas Huson. (Dawbarn 
& Ward.) Illustrated. 

tStatu-i of Birds in the British Isles and in Devonshire. By 
H. M. Evans. (Brendon & Son, Plvmouth.) Is. 

An Illustrated Manual of British Birds— Parts II. and III. By 
Howard Saunders. (Gurney k Jackson.) Illustrated. Is. each. 

A Treatise on Chemistry. By II. E. Roscoe, y.E.S., and C. Schor- 
lemmer, f.k.s. A'ol. II., Metals. Revised Edition. (Macntillan.) 
Illustrated. 31s. 6d. 

First Tear of Scientific Knou-ledge. By Paul Bert. Revised 
Edition. (Relfe Brothers.) Illustrated. 

Ambroise Part- and his Times : 13101590. Bv Stephen Paget. 
(Putnam's Sons.) Illustrated. 10s. 6d. 

Views on Some of the Phenomena of Xature. By James Walker. 
(Sonnenschcin.) 38. 6d. 

John Bright. By C. A. Vince, M.A. (Blackie.) 28. 6d. 

Nature Study in Elementary Schools. Bv Mrs. Wilson. (Mac- 
millan.) Illustrated. 3s. 6d. 

A Triji to Venus. By John Munro. (Jarrold.) Ss. 6d. 

Reader's Shakespeare — The Comedies. Bv David Charles Bell. 
(Hoddcr & Stoughton.) 3s. (>d. 

What is Life ! Bv Frederick Hovendcn. (Chapman &. Hall.) 
Illustrated. 6s. 

Notes on Carpentry and Joinery. By Thomas Jay Evans. 
(Chapman i Hall.) Illustrated. 7s. 6d. 

Experimental Work in Chemistrv. By E. H. Cook. (Arnold.) 
Illustrated. Is. 6d. 

The Tutorial C/iemisiry. Part II.. Metals. By G. H. Bailey, 
D. sc. (Clive.) Illustrated. 3s. 6d. 

Geometry for Beginners. By George M. Minchin, M.A. (Claren- 
don Press.) Illustrated. Is. 6d. 

The Observer's Atlas of the Heavens. Bv W. Peck, F.K.A.s. 
(Gall & Inglis.) 2l8. net. 



TOTAL SOLAR ECLIPSE, JANUARY 22, 1898. 

IT is gratifying to learn that those who journeyed 
to India to observe the eclipse have enjoyed all 
the opportunities which favourable meteorological 
conditions can present for the observation of a total 
solar eclipse, and there is every encouragement to 
believe that the results of the several expeditions will form 
a pleasing contrast to the almost universal failure which 
attended last year's efforts. The sun was gradually 
blotted out, and a corona of pale sUver and blue appeared. 
As the eclipse reached its zenith the temperature fell 
rapidly and the atmosphere became perceptibly chilly. The 
light during the middle of totality was greater than that 
from the full moon. The spectacle was magnificent, and 
excited a feeling of awe and astonishment among the 
beholders — a scene resembling a landscape under a wintry 
English sun. 

The general shape of the sun's corona was like that 
seen in the eclipses of 1886 and 1896 — that is to say, 
white, downy blooms winging the dark ball of the moon all 
round its circumference, but larger on each side of the 
sun's equator than elsewhere. The streamers, the light 
of which had a thready aspect, extended into space for an 
apparent distance of four and a half diameters of the 
moon. The detailed polar structure arranged itself in 
lines, as iron filings round the poles of a magnet. The 



srii\nu iMCDUL/i lvlc.:3i>ltiK 33 IKIAMUULI 
By ISAAC ROBERTS, D.Sc, F.R.S. 




February 1, 1898.] 



KNOWLEDGE. 



39 



exposures made with the kinematograph for corona were 
successful, but no shadow was observed. The spectrum 
of the chromosphere and prominences was successfully 
observed with an opera-glass fitted with a direct vision 
prism in one of the eyepieces, and the spectrum of the 
"flash" was photographed with a prismatic camera and 
with a six-iuch telescope. Indeed, all instruments, with 
the exception of the integrating spactroacope, appear to 
have responded fully to the most sanguine hopes of their 
respective manipulators, and we have had what may be 
called a record eclipse. 

Native astrologers had prophesied all kinds of calamities, 
including a tidal wave at Bombay and the downfall of the 
British raj. Immense crowds bathed in the waters of the 
Ganges at Benares, Calcutta, and other centres during the 
eclipse ; the bathers at Back Bay tied Durab grass to their 
clothes, and put some of it into pickles and preserves, to 
ensure that they should not be affected by the eclipse. 
Religious Hindus sat down and counted their beads at the 
moment of contact, at the same time reciting mantras 
or prayers, and hymns, and there was general fasting. It 
is the impression of some of the Ilmdus that when there 
was no British raj in India the solar eclipses occurred 
once in twelve years, and that they are now more frequent 
on account of the increase of sins and misdeeds. Here 
and there on the foreshore stood Parsees, zend or avasta 
in hand, and with their faces turned towards the sun ; 
priests, ever ready to receive alms, ceased their solicita- 
tions during the eclipse. Beggars, however, swarmed 
nearly everywhere, crying for alms for the recovery of the 
sun from the jaws of the dragon Riihn. 

Mr. E. Walter ^launder, whose well-equipped party was 
favoured with excellent conditions for observing and 
photographing, will contribute a detailed account of the 
eclipse to the April Number of Knowledge. 



PHOTOGRAPH OF THE SPIRAL NEBULA 
MESSIER 33 TRIANGULI. 

By Is.\Ao Egberts, d.sc, k.r.s. 

THE annexed photograph of the nebula was taken 
with the twenty-inch reflector on November 14th, 
1895, with an exposure of the plate during 
2h. 15m., between sidereal time Ih. 18m. and 
3h. 83m. A previous photograph of the object 
was taken with an exposure of three hours, on 27th 
November, 1891. 

Scale of the photograph, one millimetre to twenty-four 
seconds of arc. 

Co-ordinates of the flducial stars marked with dots, for 
the epoch 1900. 

Star(.)D.M. No. 256 Zone 29' K.A. Ih. 26m. 8-8s. Dec. N. 30° 6-5' Mag. 

„ (..) „ 260 „ „ Ih. 2Sm. I'Ss. „ 29=53-6' „ 80 

„ (•.•) „ 263 „ „ Ih. 29m. 38-5S. „ 30° 9-3' „ 9-2 

„ (::) „ 216 „ 30» „ Ih. -iSm. 49--4S. „ 30° 47-6' „ 8-4 

The nebula is referred to in the N.G.C. No. 598, G.C. 
352, h 131, and is figured in the PJiilosophkal Transactions, 
1850, Plate XXXVI., Fig. 5, and in 1861, Plate XXXVI., 
Fig. 10, and in the " Observations of NebulfB and Clusters 
of Stars," p. 20, where Lord Eosse describes its spiral 
character, which he was the first to detect. 

This nebula is one of the many that cannot be ade- 
quately described by words, or delineated by eye and hand- 
work, because of its very complicated, tortuous, and ill- 
defined structure as seen with a telescope ; but the annexed 
photograph, and, better still, the original negative, enable 
us to see the remarkable contortions, and the nebulous 
and star-like condensations, of which the nebula is 



formed. We can also see the relationship of its parts and 
their connection in the formation of the object as a whole, 
so that much of the mystery concerning it, previously to 
the revelation by the photograph, is removed. 

It will be seen that there are two large, very prominent, 
spiral arms, with their respective external curvatures 
facing north and south, and that the curves are approxi- 
mately symmetrical from their extremities to their point 
of junction at the centre of revolution, where there is a 
nebulous star of about tenth magnitude, with dense 
nebulosity, elongated in north and south directions sur- 
rounding it. Involved in this nebulosity are three bright 
and several faint nebulous stars ; the two arms are 
crowded with well-defined and with faint nebulous stars, 
having nebulosity between them ; and it is to the combined 
effect of these that the defined forms of the arms are due. 

Besides these two arms there are subsidiary arms, less 
well defined, which are constituted of interrupted streams 
of faint stars and of nebulosity intermingled together. 
Many of these stars are nebulous, and many are well 
defined at their margins, but small. The interspaces 
between the convolutions of the spiral are more or less 
filled with faint nebulosity, having curves, rifts, fields, 
and lanes, without apparent nebulosity in them. They 
are like the interspaces in clouds of smoke, and cannot be 
classified. 

There are outliers of nebulosity with many small well- 
defined stars as well as nebulous stars involved in them, 
and there are also isolated nebulous stars on the extreme 
boundaries of the nebula ; the evidence is strong that they 
are all related to the nebula. 

These descriptions, and more, can be verified by 
examination of the photograph and the negatives ; and 
they arouse iu us the desire to know the kind of cataclysm 
— for such it appears to have been — that produced the 
general smash and redistribution of the pre-existing 
matter. Was it the collision of two suns (with or without 
attendant satellites) in space, moving from opposite 
directions, with the high velocities known to exist, and 
smashing each other so that the material of which they 
were composed was scattered in a thin discoid form of a 
mixture of meteorites, meteoric dust, and nebulosity ? 
Was it a collision between two swarms of meteorites, or of 
two clouds of nebulous matter, or of one of each kind ? — 
for we know with certainty that both forms of matter 
(meteoric and nebulous) are common in space, and that 
they extend over areas of sufficient magnitude to include 
this nebula — or is there another more probable cause ? 

We may with considerable confidence draw inferences 
as to the future development of the nebula, for it is 
evidently aggregating into stars ; and those aggregations 
are assuming the various lines and curves that we can 
trace in the finished stars which are strewn over the sky. 

This nebula is not an isolated example of its class which 
has been revealed by the aid of photography. There are, 
for instance, the great nebula in Andromeda, Messier 101 
UrsK Majoris, and 74 Pischim resembling it, though the 
two last named are further advanced in symmetrical 
development than M 83 ; but it is not a tax on the 
imagination, when the respective photographs are com- 
pared with each other, to satisfy our sense of sight that 
the construction of these four nebuL? has resulted from 
similar causes, and that their developments into curves 
and lines of stars are proceeding on identically similar 
principles. 

We have as yet no guide to enable us to form an opinion 
concerning the rate of their progressive development, for 
the intervals of from four to eight years that have elapsed 
since the first and second duplicates of the photographs of 



40 



KNOWLEDGE 



[Februaby 1, 1898. 



these objects were taken, are insufficient to show sensible 
changes that may have taken place in their structures ; 
but ere long such changes will inevitably be perceptible, 
and the photographs will with certainty reveal their extent 
and character. 

Who can say that a catastrophe, such as may have 
produced any one of these nebulae, will not occur in our 
time, and that we shall not be both eye-witnesses as well 
as recorders of the beginning of another new spiral nebula, 
in addition to the convincing evidence furnished by those 
already published, showing the evolution of new stellar 
systems by processes of disintegration and re -aggregation '.' 



MOON IN ECLIPSE, JANUARY 7, 1898. 




On last Friday night I was watching the eclipse of the 
moon, and was struck with the density of the penumbra, 
which prevented the outline of the earth's shadow being 
distinguished. The penumbra also seemed irregular in 
shape. As the night was fairly clear I took a photograph 
with a twelve and a-half inch Calver's reflector, with one 
of Browning's Kellner eyepieces. Time of exposure, one 
and a-half seconds. L. Paxton. 

THE SPECTRA OF BRIGHT STARS.* 

By E. Walter Maunder, F.K.A.S. 

THERE is no branch of spectroscopy without its 
charm, but the study of the spectra of stars has 
an attraction all its own. Their hkenesses and 
their difierences are so suggestive ; they hint at 
so much of revelation as to the secrets of world 
life ; they have, like an inscription in unfamiliar characters 

* "Annals of the Astronomical Obserratory of Harvard College," 
Vol. XXVIII. Part I.— Spectra of Bright Stars photograplied with 
the 1 1 -inch Draper Telescope as a part of the Henry Draper Memorial, 
and discussed by Antonia C. Maury, under the direction of Edward 
C. Pickering, Director of the Observatory, Cambridge, Mass. (John 
Wilson & Sons, University Press. 1897.) 



and in an unknown tongue, so plainly a message to tell if 
we could but interpret them. At such interpretation we 
have indeed made our first attempts : the riddle is not all 
unread ; we have spelled out a word — it may be even a 
sentence — here and there, and, like Cleopatra's soothsayer, 
can say : 

" In Nature's infinite book of secrecy 
A little I can read." 

A little as yet ; still our knowledge grows, and the fullest 
putting together of the starry hieroglyphs, the completest 
alphabet yet formed from them, has just been laid before 
us. 

This work, like so much in the same department of 
astronomy that has preceded it, comes to us from the 
Harvard College Observatory, and from that 
section of it which the munificence of Mrs. Henry 
Draper has enabled Prof. Pickering to develop. 

The great Draper Catalogue was the result of 
a survey of all stars down to the eighth mag- 
nitude, but the dispersion employed was neces- 
sarily small, and only the most salient features 
of the dill'erent spectra were brought out. 
Volume XXVni., Part I., of the " Annals of 
the Observatory " continues the photographic 
study of stellar spectra, giving, however, but 
six hundred and eighty-one stars as compared 
with the ten thousand of the Draper Catalogue ; 
but these have been photographed on so much 
fuller a scale that our advance in the knowledge 
of stellar constitution will owe far more to it 
— and one cannot, indeed, help regretting that 
the more special discussion had not preceded the 
more general. 

The present survey is based upon examination 
of some four thousand eight himdred photo- 
graphs, representing the spectra of sis hundred 
and eighty-one of the brightest stars north of 
— 30^ declination. The instrument used was a 
telescope of eleven inches aperture and a focal 
length of one hundred and fifty-three inches, 
used in connection with objective prisms in 
number one to four, each of which had a re- 
fracting angle of about 15^. The faintest stars 
could, of course, be only photographed with one 
prism ; the brighter were therefore photographed not only 
with the highest dispersion they would bear, but in a 
number of cases with one or two prisms for the sake 
of better comparison with the fainter stars. The solar 
spectrum was photographed for comparison with the same 
telescope, combined with the Draper fifteen-inch reflector 
used as a collimator. 

The detailed study of these spectra and their classifica- 
tion has been the work of one lady. Miss Antonia Maury, 
and has occupied her nine years. The most considerable 
part of this great work is therefore hers alone, though the 
takhig of the photographs, a large part of the determination 
of the wave-lengths, and of the preparation of the volume 
for publication, fell to other members of the stafif. 

A glance at Miss Maury's classification shows how 
great an advance we owe to her. Secchi's types gave us 
but a view of the most salient differences existing between 
the stars. Vogel elaborated these considerably, and intro- 
duced the important idea of a connection between the 
type and the temperature of a star. His idea therefore 
gave us a connected evolution along a single straight line. 
Lockyer's classification was more elaborate, and was a 
further advance — at least in so far that he introduced the 
idea of rising as well as of falling temperature, and gave us 
for his line of evolution not a single straight line, but a 



February 1, 1898.] 



KNOWLEDGE 



41 



curve, with ascending and descending branches. Miss 
Maury's investigation goes further still. Her classification 
lies not in one dimension but in two, and she finds it 
necessary to divide the spectra she has examined, not only 
into "groups," forming a nearly continuous series, from 
spectra bearing a close resemblance to those of the bright- 
line nebul.B, on to the long-period variables at the extreme 
end of the series, but also into " divisions. " in which the 
leading idea is not the substances producing the lines but 
the character of the lines themselves. 

It is, of course, extremely unlikely that in this new 
classification we have arrived at finality, any more than in 
the classifications which preceded it. But this new factor 
which Miss Maury has brought to light in the course of 
her most patient study will certainly have to be reckoned 
with in the future. 

The first division in Miss Maury's scheme — Division " — 
is by far the largest, including three hundred and fifty- 
five stars out of the total six hundred and eighty one. 
In these spectra none of the single lines are relatively wide 
except those of hydrogen and calcium, and all the lines 
are " clear" — that is, they stand in distinct contrast to the 
bright portions of the spectrum. Division '' comprises 
stars in the spectra of which all the lines are relatively 
wide and hazy. The fainter hnes therefore tend to 
disappear, and in consequence those observed arc relatively 
few ; but their relative intensity remains much the same as 
in Division 'i, so that there does not appear to be a radical 
difference of constitution between the two divisions. 

Division c is in general distinguished by the strongly 
defined character of its lines, by the presence of certain 
lines apparently not found in the solar spectrum, by a 
difference in the relative intensities of the lines as com- 
pared with the solar spectrum ; and, further, the lines of 
hydrogen are narrow and well defined but less intense 
than in the other divisions, whilst the calcium lines are 
more intense. Stars of this division, therefore, would 
seem to differ more in constitution from those of Division a 
than do those of Division '■. 

Besides these three great divisions there are a large 
number of intermediate forms, whilst quite one-sixth of 
the total number of spectra cannot be assigned with 
certainty to any of these divisions, either on account of 
the faintness of the star or of the imperfection of the 
photograph. 

The cross division into " groups " is less novel than the 
one just noted into "divisions." Miss Maury's scheme 
makes the " groups " twenty-four in number. Of these, 
the first five are those in which the Orion lines are specially 
prominent — a large number of the Orion lines being now, 
of course, known to be those of helium. The sixth group 
is intermediate between the Orion type and Secchi's first 
type. The full members of this Secchi's first type are 
divided into five groups according to the intensity of the 
hydrogen lines, which are at their maximum in Group VII. 
and decrease later, and to that of the solar and calcium 
lines, which increase from group to group. The twelfth 
gi-oup comprises spectra between the first and second types, 
and the full members of Secchi's second type are divided 
into four groups with respect to the increase of the solar and 
calcium Lines. The third type is distributed over the next 
four groups, bands and flutings replacing lines. As a neces- 
sary consequence the divisional differences are no longer 
noted ; indeed, no spectra of Division b are noted later than 
Group Xn., or of l)ivision c later than (iroup XIV. The 
twenty-first and twenty-second groups correspond to 
Secchi's fourth type and Pickering's fifth type respectively. 
There remain, then, two classes unnumbered : the " com- 
posite " stars, which are probably doubles of difi'erent 



spectra apparently single from their extreme closeness, 
and bright-line stars of the Orion type. 

The annexed little table, the eighth in Miss Maury's 
Memoir, brings out in a singularly clear fashion the 
continuity of the series into which she has thus arranged 
the spectra in her hand. It will be observed that it is no 
theoretic succession ; it is based upon the actual character 
of the spectra as the photographs present them, and is 
perfectly independent of any explanation which may be 
offered as to the cause of the differences thus scheduled. 
The succession may be one of temperature, of stage of 
development, or of actual chemical constitution, and it 
might be supposed to run in either direction without in the 
slightest degree invahdating the classification here given. 
On the subject of theory Miss Maury touches lightly, but 
points out the close resemblance between Group I. and 
that of Pickering's fifth type stars. Group XXII., and that 
the latter connect us with the bright-line nebulw. This 
consideration, taken in connection with the fact of the 
obvious connection of the Orion type stars with the 
nebular regions of Orion and the Pleiades, strongly supports 
the view that the groups are numbered from I. to XX. in 
their true evolutionary order. 

Group XXL, however, stands apart from this evolution. 



Table VUI. — Relative Ihikssities of Lines. 



Intensity 
of 



Inteusity 



Intensity 



Inteusity 



Hydrogen. Orion Lines. | Solar Lines. 



11. 


20 


14» 


I 


2 


III. 


35 


162 


1 


1 


IV. 


^b 


151 


2 


3 


V. 


90 


51 


3 


4 


VI. 


100 


36 


-13 


6 


VII. 


1(K) 


5 


99 


S 


VIII. 


95 


1 


161 


13 


IX. 


95 


1 




28 


X. 


90 


1 




58 


XI. 


HO 


I 




83 


XI t. 


25 


1 


■132 


135 


XIII. 


2(1 


U 




160 


XIV. 


16 





568 


160 


XV. 


9 


(.) 


712 


200 


XVI. 


7 


u 




200? 


XVII. 


7 







200? 


XVIII. 


6 





!StlD 


170? 



For Miss Maury finds the difficulty of including the fourth 
type stars in any regular progression which others have 
found before her, and which Vogel and Lockyer have tried 
to meet by such difi'erent expedients : the former placing 
the third and fourth type stars as alternative forms for a 
late stage in stellar life history, the latter regarding Type 
III. as indicating an early stage in a star of rising 
temperature, and Type IV. as a late stage in a star of 
falling temperature. 

It is sufiiciently clear from these very difl'erent classifica- 
tions that no very sure foundation for determining the 
course of a star's evolution has yet been laid down : 
but it seems to me that in placing the long-period 
variables at the end of her series Miss Maury has been 
guided by a true appreciation of the facts before her, and 
that her scheme therein is a vital improvement on that of 
Lockyer. And to leave the carbon stars, the fourth type, 
unplaced, is probably, in the present state of our know- 
ledge, to exercise a wise discretion, though Mr. McClean's 
photographs of 1.52 Schjellerup appear to confirm Vogel's 
suggestion that both Types III. and IV. succeed Type XL, 
but as alternatives to each other. 

The connection between the divisions is a more difficult 
matter, and except possibly in one point it has to stand 



42 



KNOWLEDGE 



[Febbuabt 1, 1898. 



without explanation at present. The facts, too, that these 
divisional differences are practically traceable only amongst 
the Orion stars and those of Secchi's first type, and that 
no stars are found of Division c in Group XIV., whilst 
seven are recorded as being intermediate between Divi- 
sions a and c, point to the classification in this direction 
being neither so perfect, nor so directly the effect of 
simple causes, as the cross arrangement into groups. 

An interesting relationship, which Miss Maury mentions, 
suggests that m the case of Divisions a and /' the differ- 
ences between them may possibly be of a mechanical 
nature rather than one of temperature or constitution. 
She points out that the two spectroscopic binaries X, Ursie 
Majoris and /3 Aurigic, though really of Division a, appear 
as members of Division b at that particular point of their 
orbit when the relative motion in the line of sight of the 
two members of the system is sufficient to widen the lines 
of their composite spectrum, but not to separate them into 
pairs. It is clear, therefore, that the existence of a large 
number of close binaries might explain the occurrence of 
Division h spectra, provided that these several pairs were 
composed of stars not very unequal in magnitude, of the 
same type of spectrum, and with relative motion in the 
line of sight such that their lines were widened but not 
separated. 

We already know, by direct observation, of binary systems 
in which the periods vary from five and a half years up to 
many centuries. The Algol variables and the spectroscopic 
doubles have similarly revealed to us the existence of 
systems with periods ranging from a few hours to a few 
weeks. We may be perfectly assured that there are 
other systems with periods of an order intermediate 
between these, not of weeks or of years, but of months. 
And such, under the special conditions mentioned above, 
would give us /' division spectra. In cases where the two 
components were of different types we should have a 
"composite" spectrum. It is possible, therefore, that 
Division h and " composite " stars are but different pre- 
sentments of the same relationship — a binary system of 
two not unequal stars far too close for optical resolution. 

The researches of Darwin on tidal evolution, and of See 
on that of double stars, lead us to the conclusion, since 
double stars tend to widen with age, that these very close 
binaries are yet in an early epoch of their life history. 
The fact, therefore, that the Algol stars and those of 
Division h are most plentiful in the Orion and first type 
groups is a confirmation of Miss Maury's conclusion that 
these are early forms of spectra, and seems better to accord 
with the facts than Lockyer's view, which places the Sirian 
stars midway in the evolution. 

The test, of course, of the truth of the suggestion will 
be that a prolonged watch of Division h spectra will sooner 
or later show in some instances a gradual change into 
Division a. 

It is worth remembering that there may be a yet earlier 
stage of double star evolution : where we have a single 
star in rapid rotation, the separation into two distinct 
bodies not having as yet taken place. Such rapid rotation 
would produce a widening and a haziness of the lines — 
a " Division h " spectrum, though differing in character 
from that of the close binaries. This would not be 
periodic in its character, and so not demonstrate itself by 
the test just mentioned. 

Division c stands on a different footing, and appears to 
point to a real difference of constitution. The stars, 
however, of this division are so few in number tliat the 
progress of the groups cannot be followed out with anything 
like the distinctness of Division a. 

Annexed is a copy of Miss Maury's Table I., which 



shows at a glance how the stars observed are distributed 
amongst the various groups and divisions. The numbers 
in the lirst column refer to Secchi's types ; " designating 
Orion stars, ' ' composite spectra, /- bright-line stars. The 
last column gives the grouping of the Draper Catalogue. 
Under the heading " Division " the sub-heads nc and ah 
indicate forms intermediate between Divisions a and <• 
and a and /• respectively ; the sub-headings c h, and ah, 
<(c signify spectra which cannot certainly be assigned 
to either division, owing to the faintness of the star or 
the imperfections of the photographs. Peculiar spectra 
are ranged under the sub-head P. 

CLiaSIFICATION OF SrECTBA. 











Division. 


1 






Type. 


Group. 










Total. 


D.C. 








, 












c. 


ac. 


a. 


a, b. 1 ab. 


b. 


ab, 
ac. 


P. 






O 


I. 












7 






7 


B 


O 


II. 






"i 


5 




& 




"2 


16 


B 





III. 


i 


... 


5 


7 




5 




1 


19 


B 


o 


IV. 






11 


22 


■'3 


14 






.")0 


B 


o 


V. 


3 




9 


8 




b 






_'."i 


AB 


O-I. 


VI. 


6 




4 


9 


3 


9 






:il 


AB 


I. 


Vll. 


1 




13 


13 




17 




1 


45 


A 


1, 


VIII. 


1 


"i 


23 


6 


3 


17 




7 


58 


A 


I. 


IX. 






? 


17 


3 


9 


'5 




34 


AF 


I. 


X. 






2 


12 


2 


3 






19 


AF 


I. 


XI. 




5 


? 


11 


5 




7 


1 


29 


F 


I. -11 


XII. 


2 


3 


29 




1 








35 


F(x 


II. 


XIII. 


4 


1 


22 












27 


G 


ir. 


XIV. 




7 


40 










3 


50 


6 


II. 


XV. 






117 










1 


118 


K 


11. 


XVI. 






23 












23 


K 


III. 


XVII. 






19 












19 


Ma 


III. 


XVIII. 




... 


20 












20 


Mb 


III. 


XIX. 






10 












10 


Mb 


111. 


XX. 




... 


i 










2 


6 


Md 


IV. 


XXI. 




... 














4 


Na 


V. 


XXII. 


















4 





c. 


— 




... 














IS 


— 


L. 


- 




_ 














14 


- 


Totals 




18 


17 


355 


110 


20 


91 


12 


18 


681 





Beside the two tables given above, very complete tables 
are supplied of the wave-lengths of the lines found In 
the different classes of spectra, Fomalhaut being taken as 
the representative of the first type stars, and the star 
H.P. 1311 for the fifth type. The solar lines are cata- 
logued from the D lines of sodium to the line p of hydrogen 
far in the ultra-violet, and the lines of Division c stars 
from ^ to K of the hydrogen series of lines. The complete 
catalogue of the 681 stars arranged in order of E.A. is 
supplemented by tables in which they are arranged in 
order of spectral group, and copious notes add much 
important information as to the details of Individual 
spectra, whilst a minute description of the classification, 
group by group, occupies the longest chapter in the work. 

In view of Prof. Ramsay's striking discovery of helium, 
one naturally looks eagerlf to find the place accorded to 
that spectrum in this classification. The work was, 
however, too far advanced at the time when the helium 
spectrum was revealed to us for it to be taken account of 
in the actual classification. All that could be done was 
to add a supplementary note. In this we are given a table 
in which the helium hnes are compared with those of the 
Orion stars, and are told that all the series of both helium 
and parhelium are represented in them. It appears, 
further, that nearly all the lines of the first subordinate 
series of both helium and parhelium are very strong in 



February 1, 1898.] 



KNOWLEDGE 



Group III., and reach a maximum in Group IV., and 
fall off far more rapidly toward the later f,'roup3 than 
toward the earlier. It is important also that they are 
more clear and conspicuous in Division c than in Divi- 
sion ", and far more persistent — the lines 1-171*65 and 
3819-75 being present in Group VIII., Division c. 

Complete and thorough as the Memoir is in every other 
respect, it is impossible to escape the regret that it was 
not accompanied by a well-choseu series of photographs of 
typical spectra. \\e I'eel sure that if these could have been 
supplied, they would have adiled greatly to the value of 
Miss Maury's careful descriptions and to the information 
which is to be derived from them. 

Great as is the evident value of this Memoir, it may be 
taken as certain that we shall not be able to realize how 
heavy a debt we owe to Prof. E. C. Pickering and Miss 
Maury until it has been made the basis of the many 
researches which will inevitably be founded upon it. Nine 
years may seem a long time to have devoted to such an 
inquiry, but the more the Memoir is studied the more one 
will feel surprise, not that it has taken so long to prepare, 
but that so much has been so quickly accomplished. 



ANCIENT RED DEER ANTLERS. 

By E. LrDEKKER, J!.A., F.R.S. 

WHATEVER may be the case with regard to its 
applicability to the human race, there can be 
no question that the phrase, " There were 
giants in those days," is perfectly true when 
the antlers of modern red deer are compared 
with those of animals living a few centuries ago on the 
Continent, or with the specimens that are from time to 
time dug up from the fens of Lincolnshire and Cambridge- 
shire, or from the bogs of Ireland. Not only are such 
ancient specimens much larger in respect of length and 
girth of beam than any to be met with at the present 
day, but they also greatly exceed the latter in respect 
to the number of tines or points they carry, as also 
in the complexity of the so-called cup in which the crown 
or summit of the beam so frequently terminates. At the 
time the big antlers of the English fens and Irish bogs 

crowned the 
heads of 
living ani- 
mals, both 
Britain and 
Ireland were 
either sti 11 
connected 
with the Con- 
tinen t, or 
their separa- 
tion there- 
from was an 
event of com- 
paratively re- 
cent occur- 
rence ; and as 
the greater 
part of the 
country was 

still clothed with forest, the deer were able to wander 
about as much as they pleased, and there was nothing to 
prevent them attaining the maximum development of 
which the species was capable. And on the Continent 
the conditions of life were, if possible, still more favourable. 
Contrast this with the mode of life of the deer of the 




Fig. 1.— Skull and Antlers of Ased Scotch 
Red Deer. 



Scottish highlands at the present day. The so-called 
"deer forests" are nothing but open moorland; and as 
red deer are naturally forest-dwelling animals, this alone 
is sutVicient to account for their relatively small size and 
the small development of their antlers. When to this is 
added the comparatively small size of the area on which 
they are located, coupled with the effects of more or less 
continuous in-and-in breeding, it is but small wonder that 
the antlers of even the finest of Scotch deer are but poor 
things when compared with those of their predecessors. 
Some of our readers may perhaps be disposed to say that 
this is due to the circumstance of the deer being shot 
down at too early an age, before time has been allowed 
them to perfect the full growth of their antlers, and that 




Fig. 2. — Antlers of Red Deer from an Irish Bog. 

if they were allowed to enjoy life a few years longer their 
trophies would be fully equal to those of a past age. But, 
as a matter of fact, this is not the case. After a certain 
age the antlers of deer begin to retrograde or degenerate, 
when they develop fewer points than at the prime of the 
animal, and not unfrequently display various abnormalities. 
And as Scotch red deer are frequently killed with degene- 
rating antlers, it is manifest that this is not the cause of 
the comparatively small size of these appendages. Such 
a degenerating head, showing certain abnormalities, is 
represented in our first illustration. Like the other 
specimens figured, this example is in the collection of the 
Viscount Powerscourt, at Powerscourt, County Wicklow, 
and belonged to a very aged animal. Its history is some- 
what curious. The stag was killed by poachers in 
Ross-shire during the year 1844, and by them given to Mr. 
Hay Mackenzie, father of the late Duchess of Sutherland. 
By her Grace it was presented to Frederick, fourth 
Marquis of Londonderry, by whom, in turn, it was given 
to Lord Powerscourt in 18-57. 

English park red deer, from their more congenial sm-- 
roundings and richer pasture, develop finer antlers than 
those of their wild Scotch cousins, but even these bear uo 
comparison to those of the stags of former ages. Although 
larger antlers are still obtained on the Continent, these 
are — for the most part, at any rate — inferior to those killed 
years ago. It is true that in the Carpathians and Caucasus 
magnificent heads are still fairly common. But these 
belong to a variety known as the Maral or Caspian red 
deer, in which the face is longer than in the typical race 
of Western Europe, and the coat more or less distinctly 
spotted with white in summer, while, as a rule, the crown 



44 



KNOWLEDGE 



[Febbuarv 1, 1898. 




Fig. 3. 



-Antlers of Ancient German Ked Uc 
inirchascd in Berlin in 1S63. 



of the antler is less distinctly cupped and carries fewer 
points. Still, it is very difficult in many instances to dis- 
tinguish the antlers of the two races, which, in certain 
districts of the Austrian Empire, probably pass imper- 
ceptibly into one another. 

. This inferior development of modern red deer antlers 
being then a well-ascertained fact, it is a matter of con- 
gratulation that there exist a few collections where the 

trophies of the 
/f \\ ancient giants 

i Ml i \S\. 1 have been 

vT/y \^ i ^'Ccumulated 

■■"" \ m # ^jj^ preserved 

almost from 
time i m • 
memorial, or 
where judici- 
ous purchase 
has assembled 
a series which 
it would be 
almost, if not 
quite, impossi- 
ble to rival at 
the present 
day. Ofcollec- 
tioDS of the 
former kind, 
by far the 
finest is the 
one belonging 
to His Majesty 
the King of 
Saxony, at the old hunting schloss of Moritzburg, near 
Dresden. Of the latter type, so far as the United 
Kingdom is concerned, the celebrated collection of Viscount 
Powerscourt, already mentioned, is far and away ahead of 
all others. By the kindness of the owner, the present 
writer has been favoured with photographs of a series of the 
finest specimens in this collection, from among which a few 
have been selected to illustrate the present article. 

From the great individual variation displayed in a large 
series, the uninitiated often find considerable difficulty in 
distinguishing the antlers of red deer (including under 
this term the different races thereof) from those of the 
allied species. Nevertheless, after some practice, this is a 
comparatively easy matter ; and the subject is one of 
considerable interest, on account of showmg, in spite of 
great individual variation, the adherence to one distinctive 
type of structure. The red deer and its allies form a 
small and well-defined group of the genus Cenm^, among 
which are included the wapitis of North America and 
Central and North-Eastern Asia, the hangul of Kashmir 
and Yarkand, and the great shou of the district lying to 
the northward of Bhutan. In all these deer the minimum 
number of tines to each antler is five, but there may be 
as many as twelve, or even more. A very general and 
especial peculiarity of the group is the presence of two 
tines on each side in close proximity to the forehead. The 
presence of these two tines is, indeed, as a normal feature, 
limited to the members of this group, and even among 
them it is by no means invariably constant. There is, 
for instance, a Tibetan species, known as Thorold s stag, in 
which the second is wanting, and the so-called brow-tine 
alone remains in this part of the antler. The presence of 
this second tine in the red deer group is clearly, then, 
what naturalists term a specialized feature of comparatively 
recent acquisition. And further testimony in favour of this 
is afforded by the circumstance that even in well-developed 



heads this tine is frequently much smaller on one side than 
on the other. This is shown in Fig. 2, where the second tine 
on the right side is scarcely more than half the length of its 
fellow on the left. Even more significant is the fact that in 
heads which are degenerating — or, as sportsmen say," going 
back "—this tine is the first to disappear, or to diminish in 
size. An excellent example of this is afforded by the head 
represented in Fig. 1, where it is completely wanting on 
the right side, and is small and rudimentary on the left. 
Indeed, among Scotch deer the second tine is very 
frequently wanting even during the prime of life, thus 
affording further evidence of the decadence of that stock. 
It is also wanting in the small island race of Corsica and 
Sardinia, as it is very frequently in the larger race 
inhabiting the North of Africa and Spain. The red deer 
being typically a northern species, the degeneracy in the 
latter instance is probably due to the warmer and therefore 
less suitable climate. 

At some distance above the second is given ofi' a large 
third tine, which is quite distinct from those above it. In 
fuUy developed heads of the red deer of Western Europe, 
as exemplified by Figs. 2 ;',nd 3, the beam of the antler 
continues undivided for an interval somewhat exceeding 
the one between the second and third tines, after which it 
expands to form a more or less distinctly defined cup 
whose margins are bordered by a variable number of snags 
or tines of different length. In heads of this type it is 
scarcely possible to distinguish a separate fotirth tine. 
Nevertheless, in heads where the cuppin;.' is less con- 
spicuously developed, the fourth tine exists as a separate 
portion of the antler, the cuppin;,' being then confined to 
the termination of the beam above. This type of antler is 
shown by the German head depicted in Fig. i ; and it may 
be noted that in the Carpathian race of the species it is 
common to find the fourth tine remaining more or less 
distinct, as it does in the degenerate modern Scotch deer. 
The shape of the cupping varies considerably in different 
individuals, as may be seen by comparing the old Ger- 
man head represented in Fig. 3 with the one from an 




Fig. 1. — Antlers of German Red Deer with Twenty Points. 

Irish bog which forms the subject of Fig. 2 ; the former 
showing a total of eighteen and the latter of nineteen 
points. Considerable individual diversity also exists with 
regard to the angle at which the antlers are set on the 
forehead. For instance, in Fig. 2 they are directed much 
upwardly, and this is still more markedly the case with 
Fig. 3 ; but as the latter specimen consists of separate 
antlers affixed to an artificial head, the degree of inclina- 
tion is not altogether to be depended on. The subject of 
Fig. 5, which is also an ancient German head, is, however, 
in its original condition, and here it will be noted that the 
degree of divergence is very great. This head, too, is 



February 1, 1898. 



KNOWLEDGE 



45 



remarkable for the number of its points, which reach a 
total of twenty-two ; and the almost complete abaorption 
of the fourth tine in the terminal cup-like expansion is 
also a feature which can scarcely fail to attract attention. 
Two-and-twenty is, however, by no means the maximum 
of points, as a pair of antlers from an Irish bog, formerly 




Fig. .". — Antlers of Ancient German Ret) Deer with 
Twentv-tffo Points. 

in the collection of the late Sir Philip Egerton, but now 
in the British Museum, carry no less than thirty. And it 
must not be supposed that modern Scotch stags never 
make an approach to such high numbers, a specimen shot 
some years ago by Lord Burton exhibiting a total of 
twenty. 

Ill spite of the individual variations alluded to, the form 
of the fourth tine and the terminal cup alTords an easy 
means of distinguishing the red deer antler from that of 
the wapiti, whether American or Asiatic. In the latter 
the fourth tine always forms a huge forwardly projecting 
prong, much larger than either of the three tines below, and 
situated in the same fore-and-aft plane as the tines above, 
which are normally quite distinct from one another, and 
thus do not form a terminal cup. Occasionally, however, such 
a cup is formed even in wapiti antlers ; and it is said that 
in certain districts of America such cupped antlers are by 
no means uncommon, being apparently hereditary. Even 
in such instances, however, an experienced eye will have 
no difficulty in picking out the wapiti antler, for the great 
fourth tine always retains more or less of its characteristic 
form and size, and the whole antler is thus quite unlike 
that of any red deer. 

It has already been said that the red deer of Eastern 
Europe usually have the terminal cup less developed than 
in the old giant race of the more westerly districts ; and, 
as we proceed further to the north-east in Asia, the antlers 
of all the nearest relatives of this species tend to become 
simpler still. For instance, in the hangul, or Kashmir 
stag, the number of points on each side rarely exceeds 
six or seven ; while in the still larger shou, of the country 
to the north of Bhutan, they are limited to five a side, no 
trace of a terminal cup being formed. Clearly, then, the 
group attained the culminating complexity of antler 
development in the countries of Western Europe : and 
whether this complexity would have gone on increasing to 
an almost indefinite degree had not man appeared on the 
scene, and checked the further evolution of these and most 
other animals, may afford an interesting subject of specula- 
tion to the curious. Equal room for speculation exists as 
to the purpose of the great complexity exhibited by the 
antlers of the red deer. As fighting weapons, the huge 
but simpler horns of the shou would seem to be at least 



equally efficacious ; and to human taste it is by no means 
certain that their severer simplicity of form is not more 
graceful than the many-branched red deer horn. But it 
by no means follows that human and cervine festheticism 
run on the same lines ; and if antler development be due 
to female preference for the stags with the finest horns, a 
i-eni ciiusii may exist in this direction. 

All the different variations of red deer antlers alluded to 
above are of a more or less strictly normal type, but there 
are other variations less commonly met with which come 
under the designation of abnormalities, or monstrosities. 
And althoui,'h such attract much attention from sportsmen 
and amateurs, the scientific naturalist, as a rule, has no 
more to do with them than he has with two-headed pigs 
or three-legged chickens. Nevertheless, there may be 
exceptions even to this general rule, and a case in point 
seems to be afforded by a peculiar head of a French red 
deer in the Powerscourt collection, which forms the subject 
of Fig. (). From this figure it will be seen that the left 
antler is of normal form, exhibiting the first, second, and 
third tines, and a rather small terminal cup, of which the 
fourth tine forms a constituent part. The right antler, on 
the contrary, is double from base to summit, and of a 
much simpler structure, each portion consisting =;olely of 
a long unbranched beam, with a brow-tine at the base, and 
a simple four-pointed cup-like expansion at the crown. 
Xow at first 
sight there 
might seem 
nothing par- 
ticularly note- 
worthy in this, 
for in all cases 
of such dupli- 
c ation the 
divided antler 
is of a simpler 
type than the 
ordinary un- 
divided one. 
But the curi- 
ous feature in 
this instance 
is that the 
duplicated 
antlers are of 
the same 
general type as 

certain peculiar antlers of the Eastern race of the red 
deer frequently met with Ln the Crimea and Asia Minor. 
And although these latter are undoubtedly to a certain 
extent abnormalities, yet from their comparative frequency 
in the districts in question they scarcely come under the 
designation of monstrosities. Whether the undoubted 
resemblance existing between the duplicated French antler 
and these abnormal Eastern specimens is anything more 
than a coincidence, the facts at our disposal are not 
sufficient to admit of determining. At any rate, the 
point is of sufficient interest to merit mention. A 
similar duplication of one antler — and, curiously enough, 
on the same side — has been recorded in the fallow deer ; and 
Lord Powerscourt also possesses a second French red deer 
head in which the right antler is bifurcated for half its 
length. Probably the circumstance that the abnormality 
in all these three instances is on the right side is a mere 
coincidence. It would, however, be matter of some little 
interest if it could be ascertained whether such malfor- 
mations are due to any injury received by the animal 
previous to the growth of the horns. 




Fig. i>. — Antlers of Frencli. Red Deer, with 
Duplication on the Right Side. 



46 



KNOWLEDGE 



[Febkuaky 1, 1898. 



NOTES ON COMETS AND METEORS. 

By W. F. Denning, f.r.a.s. 
Comets. — Pons-Winnecke's comet was detected by Mr. 
C. D. Perrine at the Lick Observatory on January 1st, 
when it was described as very feebly visible. It may well 
have appeared faint, seeing that its distance from the 
earth was more thau one hundred and sixty million miles. 
Presumably the comet was picked up with the thirty-six 
inch refractor; but as the object is rapidly approaching the 
earth, and gaining in apparent brilliancy, much smaller 
telescopes will now have the capacity to reveal it. Hille- 
brand's elements for the comet are : — 

Epoch March 15th, 1898. 

iM 359=^ 3' 52-0' 

ir 274' 14' 390' 

H 100° 53' 11-5' 

I 16° 59' 33-8' 

<^ ... 45° 37' 14-1 " 

/x ... 608"-5559 

Ephemeris for Berlin, midnight. 
E.A. 
H. M. .5. Dec. 

Feb. 10th 18 8 30 ... 12° 29-8' 
12th 18 18 35 12° 47-8' 

14th 18 28 48 ... 13° 5-1' 

IGth 18 39 .. 13° 21-0' 

18th 18 49 28 ... 13° 35-4' 

20th 18 59 56 ... 13° 48-2' • 
On February 1st the comet's distance will have decreased 
to about one hundred and thirty-three million miles, and 
it will be visible before sunrise iu the southern region of 
Ophiuchus. The moon sets on the morning of February 
1st at 4.15, and the comet may possibly be picked up about 
two degrees north of the star 47 Ophiuchi (magnitude 6-3). 
Perrine's comet (/) 1897, discovered October lOth) aud 
D'Arrest's comet have become too faint to be observable in 
ordinary telescopes. The former was seen on November 
18th and 23rd, 1897, with a sixteen-inch refractor, at 
Northfield, Minn., as a very faint elliptical glow, three 
minutes long and one minute wide, without any perceptible 
condensation, and so feeble that the slightest illumination 
of the micrometer wires overpowered it. Three sets of 
elements have been published, as follows : — 

Pavue and Young. Perrine. Moller. 

T 1897, "Dec. 8-9216 G.M.T. Deo. 8 8471. Dec. 8 6899. 

66" 10' 11" 66" 5' 42" 65° 56' 3-1" 

a ... 32" 4' 9" 32° 4' .5" 32" 3' 27" 

■ . . 69" 37 21" 69" 37' 41" 69° 36' 36" 

lug. q. 013186 O13206 0-13242 

In Ast. Xacli., 3471, Herr Bidschof gives some compu- 
tations with regard to the ensuing return of the comet 
(Tempel, 18(56, I.) of the November meteors. He supplies 
a sweeping ephemeris, from which it appears the comet 
will probably traverse Aries iu March and April, Taurus 
in May and June, Gemini in July and August, and enter 
Cancer at the middle of September. The great distance 
of the comet and the uncertainty attaching to its precise 
position, will, however, prevent its being seen. In the 
summer and autumn of 1898 the comet aud earth will 
rapidly approach each other, and the former may possibly 
be rediscovered in the winter followmg. 

Meteors. — T'le Leunich of 1S97. — Herr A. A. Nyland, 
of Utrecht, reports that on November 13th he watched 
the sky from 12h. 51m. to 16h. 7m., and saw twelve 
meteors, of which seven were Leonids and three Taurids. 
November 14th was cloudy. On November 15th observa- 
tions were made between 13h. 8m. and 16h. 45h., and 
forty meteors were recorded, including thirty-two Leonids. 
There was a well-defined radiant at 152° + 24" and a 



secondary position at 150° + 29°; no less than ten very 
bright Leonids were observed, five being estimated to equal 
first magnitude stars, one equal to Jupiter, and four equal 
to A'enus. Fifteen of the Leonids left bright streaks. 'The 
larger meteors exhibited an orange colour in five cases, and 
a green hue in four cases. 

At the Radclifle Observatory, Oxford, Messrs. Wickham 
and Robinson maintained a watch on November 13th 
from llh. 15m. to 17h. 45m. There were occasional 
clouds and moonlight was troublesome, so that during the 
night only about forty meteors were seen. The nights of 
November 14th and 15th were cloudy. 

Prof. A. S. Herschel, at Slough, observed about ten 
meteors and no certain Leonids on November 13th, during 
an extended watch of about seven hours between 9h. 30m. 
and 18h. The sky was overcast on November 14th. 

Sir W. J. Herschel and Mr. J. C. W. Herschel, at 
Littlemore, near Oxford, on the night of November 13th, 
between 12h. 30m. and 16h. 15m., counted twenty-one 
meteors, including about seven Leonids. 

Herr Franz, at the Observatory at Breslau, on November 
13th, saw six meteors (three Leonids) ; and on November 
14th before 16h. recorded twenty-one meteors, including 
fourteen Leonids, from a radiant at about 145° + 25°. 

Herr Rigginbach, at Basel, on November 13th, between 
12h. 80m. and 14h. 30m., counted nineteen meteors (ten 
Leonids). The following nights were cloudy. 

The number of bright Leonids observed by Nyland on 
the morning of November 16th indicates that, had the 
sky been favourable before sunrise on November 15th, the 
shower was, probably, a conspicuous one. Herr Franz's 
observations on the morning of November 15 th terminated 
at 4h. (= G.M.T. 2h. 62m. a.m.), and before the maximum 
occurred. 

Two of the meteors seen by Sir W. J. Herschel and 
Mr. J. C. W. Herschel, near Oxford, were also recorded by 
Jlessrs. Wickham and Robinson, at the Radclifle Obser- 
vatory, Oxford, and by Mr. W. E. Besley at Walthamstow. 
The meteors were of the first magnitude. One appearing 
on November 13th, 15h. 28m., was a Cmicrid, descending 
from one hundred and twenty-five to seventy-seven miles 
over the North Sea to Halesworth, in Sufi'olk. The other 
was a true Leonid, appearing at 15h. 52m., and falling 
from one hundred and three to fifty-nine miles over the 
Strait of Dover to Cranbrook, in Kent. 

Tlie Geminiils. — Moonlight greatly interfered with obser- 
vations of this shower. Mr. E. N. CuUum, of Whitby, 
reports, however, that meteors were both numerous and 
brilliant on the evening of December 12th. He recorded 
ten between 8h. and 9h., and many others were seen 
afterwards. They were nearly all (ieminids. 

During the past autumn an unusually large number oi 
fireballs have been observed. In the majority of cases, 
however, the observations were not sufiiciently precise and 
complete to allow real paths to be computed. Three 
splendid meteors, appearing at convenient times in the 
evening, were widely observed, and from a large number 
of descriptions I worked out the following results :— 

Rr.\L P.4THS OF Thbef: Firfuvlls, 1S97. 



Date audliour 


(1) October 2 
fib. 23m 


hid. 


(2) Dec. 9th. 
9h. 47m. 


(3) December 12th. 
8h. 6m. 


Brightness 

Height at besrinning. 
Position over ... 

Heig-ht at ending 
Position over 


SSiniles 

Wooler. North 11 m 

berlaiid 
S5 miles 
Lat.55''10 N.long 


76 miles 
Aldeburgh 

21 miles 
Eoyston 


. 112 miles 
. Lat. 54° N., long. 
l'>28 E. 
19 miles 
. Nortli of Tliirsk 


Earth point 

Real length of jmth .. 

Velocit.v 

Radiant point 

Inclinationot meteor's 

descent 
Parent system... 


Korth Sea 
171 miles 
Very slow . 
218° -HO" . 

80 

i' BoStids 




Ampthill 
90 miles 
Rather swift 
113° -H 32* 


Richmond, Yorks. 
151 miles 
. 25 miles per second 

. 80° + 23« 

. 38° 
C Tanri.ls 



February 1, 1898.] 



KNOWLEDGE 



17 



In February no special showers are due, but large 
meteors are often observed on about the 7th and 10th. 
At this period there is a well-defined shower from 74''+ l.S", 
near a AuriijiB, which needs further watching. 



THE FACE OF THE SKY FOR FEBRUARY. 

By Herrert Sadler, t.r.a.s. 

A FEW, but not many or large, spots are visible on 
the Sun's disc. 
Conveniently observable minima of Algol occur 
at lOh. IHm. p.ji. on the 9th, at 7h. 2m. p.m. 
on the 12th, and at 3h. 7m. a.m. on the 27th. 

Mercury is a moruing star, but is badly placed for obser- 
vation on account of his considerable southern decli- 
nation. On the 1st he rises at Gh. 27m. a.m., or about 
one hour and a quarter before the Sun, with a southern 
decUnation of 21° 18', and an apparent diameter of 6^". 
On the 10th he rises at 6h. 36m. a.m., with a southern 
declination at noon of 21^ 8', and an apparent diameter 
of 5|". On the 20th he rises at 6h. 40m. a.m., with a 
southern declination at noon of 18° 2.5', and an apparent 
diameter of 5;^". After this he is too near the Sun to be 
conveniently observed. He describes a direct path while 
visible through a portion of Sagittarius into Capricornus. 
He is in conjunction with Mars at 6h. p.m. on the 11th, 
but of course both planets will have set. 

Venus is in superior conjunction with the Sun on the 
15th, and Mars is practically invisible. 

Ceres is still fairly well placed for observation, southing 
on the 1st at S'h. 5m. p.m., with a northern declination of 
29^ 29', and a stellar magnitude of about 7j ". On the 
14th she souths at 8h. 10m. p.m., with a northern 
declination of 29° 46'. On the 28th she souths at about 
7h. 15m. p.m., with a northern declination of 29° 58'. 
During the month she describes a short looped path in 
Auriga. 

•Jupiter is now very well situated for observation, rising 
as he does on the 1st at lOh. p.m., with a southern 
decUnation at noon of 2° 42', and an apparent equatorial 
diameter of 41'. On the 10th he rises at 9h. 22m. p.m., 
with a southern declination of 2° 81', and an apparent 
equatorial diameter of 42". On the 20th he rises at 
8h. 40m. P.M., with a southern declination of 2° 18', and 
an apparent equatorial diameter of 43". On the 28th he 
rises at 8h. 2m. p.m., with a southern declination of 1° 55', 
and an apparent equatorial diameter of 48V'. During the 
month he pursues a retrogi-ade path in Virgo, being about 
1|° south of / Virginis towards the middle of the month, 
the two objects forming a fine naked-eye double star. 

Saturn and Uranus do not rise till some time after 
midnight at the end of February. 

Neptune is still favourably situated for observation. He 
rises on the 1st at 2h. 29m. p.m., with a northern decUnation 
of 21° 42', and an apparent diameter of 2^". On the 
10th he rises at Ih. 40m. p.m., with a northern decUnation 
of 21° 42'. On the 20th he rises at Oh. 54m. p.m., with 
a northern decUnation of 21° 42'. On the 28th he rises 
at Oh. 28m. p.m., with a northern declination of 21° 48'. 
He is nearly stationary in Taurus during the month, in a 
region barren of naked-eye stars. 

There are no weU-marked showers of shooting stars in 
February. 

The Moon is full at 6h. 24m. p.m. on the 6th ; enters 
her last quarter at Oh. 35m. a.m. on the 14th ; is new 
at 7h. 41m. p.m. on the 20th ; and enters her last quarter 



at llh. 13m. a.m. on the 28th. No bright star is occulted 
at any convenient hour for the amateur observer in 
February. 

(2E!)tss Column. 

By C. D. LocooK, n.A. 



Communications for this column should be addressed to 
C. D. LococK, Burwash, Sussex, and posted on or before 
the lOth of each month. 

Solutions of January Puzzles. 

No. 1. 
1. R to Kt7, dis. ch., K moves. 2. P x B, becoming a 
Black Knight, dis. ch., Kt to B2, dis. ch., mate. 

No. 2. 

1. P X E, becoming a Black Rook, Castles ! (<() 2. R to 
QB5, B to Esq, mate. 

(a) This is a fresh Rook, and evidently, therefore, has 
not moved. The Black King has not moved (by hypothesis), 
so that Black is perfectly justified in Castling. 

No. 3. 

1. P to K8, becoming a Black Knight, ch. 

[Both sides being mated simultaneously, the game 
seems a fair draw. Any other move, such as R to B8, 
would lose. J 

We regret that all the above have proved either un- 
attractive, or, from their novelty, perhaps, too difficult for 
our solvers. 

/"'. W. A, (le Tabeck. — The "Chess Intelligence" is in- 
tended to be a permanent record of chess events. In a 
monthly magazine it is obvious that it cannot usually be 
news. The publication of problems has, during the last 
nine years, resulted in many hundreds of solutions and 
inquiries. For some years an annotated game was printed 
regularly in every number. During all this time there 
was not one particle of evidence to show that these games 
were ever played through. We are glad to hear of the 
exception, and shall endeavour in future to consider the 
undoubted rights of the minority. 



PROBLEMS. 

No. 1. 

By W. Clugston (Belfast). 

Buck (;i). 









m $ iEi ' 



1^1 






White (H). 

White mates in two moves. 



48 



KNOWLEDGE 



[Febrcary 1, 1898. 




White (li). 

White mates in three moves. 

Game played in the Hastings International Tourney. 

(Jueen's (iambit ilerUneit. 



White. 




Black. 


(H. N. Pillsbnrv.) 




(A. Burn.) 


1. P to Q4 


1. 


PtoQ4 


2. P to QB4 


2. 


P to K3 


3. QKt to B3 


3. 


KKt to B3 


4. B to Kt5 (n) 


4. 


B to K2 (/<) 


5. P to K3 


5. 


Castles 


6. KKt to B3 


6. 


P to QKtS 


7. R to Bsq 


7. 


B to Kt2 


8. P X P [c) 


8. 


KtxP 


9. BxB 


9. 


QxB 


10. KtxKt 


10. 


BxKt 


11. B to Q8 


11. 


E to Bsq id) 


12. P to K4 


12. 


B to Kt2 (e] 


13. Castles 


13. 


Kt to Q2 


14. Q to K2 


14. 


P to QR3 ( f 1 


15. E to QB8 


15. 


P to QB3 


16. KR to QBsq 


16. 


P to QKt4 


17. Q to KB ('/) 


17. 


E toB2 


18. Q to B4 


18. 


QR to Bsq 


19. P to K5 


19. 


P toQBl(A) 


20. BxPch 


20. 


KxB 


21. Kt to Ktoch 


21. 


K to Ktsq 


22. R to R3 (/) 


22. 


q to Ksq 


23. Q to R4 


23. 


K to Bsq 


24. Kt to E7ch 


24. 


K to Ktsq 


25. Kt to B6ch 


25. 


K to Bsq 


26. KtxQ 


26. 


KxKt 


27. Q to Kt5 


27. 


PxP 


28. R to RBch 


28. 


Eesigns (./) 


Notes. 






This and the next four 


moves constitute Mr. 


)ury'3 favourite development 


I 


t was probably origi- 



nated by Mr. Steinitz. 

(h) Best ; though there is a well-known trap by 4. . . . 
QKt to Q2 ; 5. P X P, P x P ; 6. Kt x P, Kt x Kt ; 7. B x Q. 
B to KtSch, etc. 

((•) The logical reply to the Queen's Fianchetto. If 
Black retakes with the Pawn, White takes the free 
diagonal with &. BQ3, retaining command of the QB file, 
while the Black QB is blocked. If, as here, he retakes 
with the Knight, White gains time afterwards by P to K4. 

(d) Obviously, if 11. . . . BxP, 12. P to QKtS, Q to 
KtSch, 13. Kt to Q2. The move made is forced, as White 
threatens to win a Pawn by Q to B2, unless, indeed, he 
can venture on 11. ... Q to KtSch. 



{c) If now 12. ... B X P, 13. Q to E4 wins a piece. 
Or if 12. ... Q to Kt5ch. 13. K to K2, B x EP, 14. E to 
B3, Q x Pch ; 15. R to B2, Q to E6 ; IC. Q to Esq. We 
cannot, of course, say for certain if this was Mr. Pillsbury's 
idea. 

(/) A wasted move. Black is apparently trying to keep 
hia majority of Pawns on the Queen's side, when it would 
be safer to free his game by P to QB4. Nevertheless, his 
plan is suflBciently ingenious and characteristic. 

((/) \\ith a view to the direct attack on the King which 
follows. 

(/i) Completely overlooking Whites intention. He should 
play Kt to Bsq. 

(/) Threatening R to R8ch. If now 27. . . . Kt to Bsq, 
28. Q to E4, Kt to Kt3 ; and White mates in three moves. 

(./■) For if 28. . . . Kt to Bsq, R x Ktch, followed by 
R X E, wins everything. The whole finish was very pretty 
and forcible. 



CHESS INTELLIGENCE. 



The first-class amateur tourney at Llandudno resulted 
in a win for Mr. A. Burn with the fine score of nine out of 
ten games played. He lost, only to Mr. Bellingham, who 
took the second prize, Mr. -Jones being third. Messrs. 
Owen, Sherrard, and Gunston were among the unsncceasful 
competitors. 

The Hastings Annual Chess Festival is fixed for January 
24th-27th. Besides the leading English masters, M. 
•Janowski is expected to be present. 

A telephone match, played on December I8th between the 
City of London Club and the Yorkshire Chess Association, 
resulted in a victory for the former team by 5i games to 2^. 
On the same day Surrey defeated Kent by 13 games to 7. 

The Vienna and St. Petersburg Chess Clubs are playing 
a match of two games by correspondence. 



KNOWLEDGE, PUBLISHED MONTHLY. 

Contents of No. 147. 



PAGE 

The Kurkinofcosm, or World of 
Crustacea. By the Rev. Thomas 
Stebbin?. 



(/Iln»(rotod) 



A Dr(.wiieil Contilieut. By E. 

Lydekker, b.a., f.k.s ."? 

Is Weather affected by the Moon ? 

By Alex. B. SlcUowall, m.a. 

(liliisti-akd) 5 

Serpents and how to recognize 

them. By Lionel Jervis 7 

The Prismatic Camera during 

Total Eclipses. By Wm.Shackle- 

ton, F.K.A.s. [lUvxtrat'i) 9 

Notes on Comets and Meteors. 

By W. F. Denning, f.h.a.s 10 

Ricbard Proctor's Theory of the 

Universe. ByC. Easton. (lilus- 

(i-afed) 12 

Plate.— Photographs showing " Reversmg Layer " and Coronal Bing. 

NOTICES. 

Bound volumes of Ksowledoe, New Series, can be supplied as follows :— 
Vols I.. II., ni., and Vni., 10s. 6d. each ; Vols. VI., VII., IX., X., and XI. 
(1896), 8s. 6d. each. 

Bindin? Cases, Is. 6d. each : post free, Is. 9d. 

Subscribers' numbers bound (includinsr case and Index), 2s. 6d. each volume. 

Index of Articles and Illustrations for 1891, 1892, 1894, 1S95, and 1S9« can be 
snpplied for ;{d. each. 



PAGE 

British Ornithological Notes. 

Conducted by Harry F. 

Witherby, f.z.s., m.b.o.t. 14 

Science Notes 15 

Letters : — A. T. Masterman ; A. 

Graham, m.a. ; Thos. J. Haddy ; 

W. H. S. Monck; "I^otamu^" 16 
Notices of Books {IHmtyattd) ... 18 

Books Beceived 21 

Obituary 21 

Botanical Studies. — I. Vaucberia. 

By A. Vaughan Jenninsrs, p.l.s., 

F.o.s. (nimtraUd) .' 21 

The Face of the Sky for January. 

By Herbert Sadler, F.s.A.S. . 23 
Chess Column. By C. D. Locook, 



TERMS OF SUBSCRIPTION. 

AUSITAL StTBSCBIPTlOS, 8S., PoST FbEE. 

Knowledoe as a Monthly Magazine cannot be reristered as a Newspaper 
for transmission abroad. The terms of Subscription per annum are therefore 
as follows :— To any address in the United Kingdom, the Continent, Canada. 
Unit;d States, Egypt, India, and other places in the Post.il Union, the 
Subscription is 8 shillings, including postage ; or 2 dollars ; or 8 marks ; 
or 10 francs. 

For all places outside the Postal Union, B shillings in addition to the postage. 

Commnnications for the Editors and Books for Review should be addressed 
Editors, " Kkowlkdoe," 326, High Holborn, London W.C. 



March 1, 1898.] 



KNOWLEDGE 



49 




Founded in i88i by RICHARD A. PROCTOR. 



LONDON : MARCH 1, 1898. 



CONTENTS. 



By 



The Total Solar Eclipse, January 22, 1898. 
K. Waitbe Maunder, f.r.a.s. {Illustrated) 

British Bees.— I. Bv Feed. Enock, f.i.s., s.e.s., etc. 

(Ilhistrated) ... ' 

The Vinegar Eel, By C. Ainswobth Mitchhli, b.a.., f.i.c. 
Botanical Studies.— II. Coleochsete. By A. Vaitohan 

Je.vninOS, f.l.s., f.G.S, (Illustrated) 
Cloud Belts. By Wii, Shacklbtox, f.r.a.s. (Plate) 
A New Theory of the Milky Way. By C. Easton 
Letters :— David Flanbrt ; W. H. S. Moxck ; W. Sid- 

QKEATKS ; L. HeUSLKT ; S. H. WeIOHT 

The Masses and Distances of Binary Stars. 

J. E. GOEE, F.B.A.S ... 

Science Notes 

Notices of Books 

Short Xoiices 

Books Received 



Bv 



Conducted bv Haebt F. 



British Ornithological Notes. 

WiTHBEBT, F.Z.S., M B.O.r 

Obituary 

The Karkinokosm, or World of Crustacea.— II. By 

the Eev. Thomas K. R. Stebbixo, M.A., f.e.s., f.l.s. 
(Illustrated) 

Notes on Comets and Meteors. By W. F. DBNyiNO, 

F.B.A.S. ... 

The Face of the Sky for March. By Herbert Sadleb, 

F.R.A.S. . ... ... 

Chess Column. Bv C. D. Locock, b.a 



THE TOTAL SOLAR ECLIPSE, JANUARY 22, 1898. 

By E. Walter Maunder, f.r.a.s. 

THERE could hardly be a greater difference than 
between the eclipse of 1896 and 1898. The 
shadow track in the former case ran through a 
vast extent of country which offered, however, but 
few suitable sites. These were clustered together 
at two or three main points, and in almost every case the 
intending observers were disappointed of the spectacle 
which they had come to see. In 1898 the eclipse track 
lay chiefly in one single country which offered a large 
number of easily accessible sites, nearly all of which were 
occupied, and all were favoured with the most perfect 
weather. Up to the present time it certainly is the record 
eclipse, either as regards the number of observers, the 
character of their equipment, or the unchequered favour 
which they experienced from the weather. 

" A victory all along the line," is what we have to 
record. The full significance of that victory and what 
results may accrue from it, it will take us many months to 
learn. 



As a sensation the eclipse did not fulfil the popular 
descriptions. Whether, as has been asserted, the corona 
was unusually large and bright, or from the special 
atmospheric conditions prevailing in India at the time, the 
darkness was much less than is usual in any ecUpse of two 
minutes' duration, and the general effects in colour, light, 
and the appearance of the landscape were very much 
those which were brought about more slowly some four 
and a half hours later some thirty-five or forty minutes 
after the sun had set. At any rate, the light at mid- 
totality was certainly greater, considerably greater, thin 
we ordinarily get at night at the full of the moon. 

The fall of temperature was, however, considerable, 
amounting to some twelve degi-ees ; and it was noticed by 
some of those who had taken part in the Norway expedition 
of 1896 that, whereas on that occasion the darkness of the 
eclipse was felt to be a sensible relief from the unceasing 
sunlight, so now the coolness of the eclipse was a relief 
from the too powerful heat of the sun. 

Consistently with the small amount of darkness of the 
eclipse the approach of the shadow at the beginning of 
totality was less marked than usual, and in some places, 
though watched for, escaped notice. The only record 
that has yet reached me of its approach having been 
distinctly observed is from Dr. Robertson, of Nagpur. 
The shadow-bands were also looked for at some stations 
without success, though they were caught at both .Jeur 
and Nagpur. At the latter place Miss Henderson, m.d., 
describes them as having been faint dusky ripples some 
two inches in breadth, and separated from each other by 
about the same mterval, and in appearance and speed of 
motion resembling the ripples seen on the ceiling of a 
cabin in an ocean steamer as they are deflected through 
the porthole from the water outside. 

Of the stars visible during the eclipse one caught every 
attention, and was, indeed, seen after totality had passed. 
This was the planet Venus, some six degrees south-west of 
the sun at the time. Mars, though very small and further 
from the sun, was also glimpsed, and some two or three 
other stars were noted. 

The shape of the corona recalled at once that of 1896, 
and with it the two earlier years 1868 and 188C, which it 
had resembled. To the south-west a long ray nearly in 
the solar equator was easily traceable for two, if not three, 
solar diameters from the dark limb of the moon. On the 
east side a pair of broader and less-extended streamers 
formed a single connected structure in which the charac- 
teristic coronal curves were repeatedly seen. 

Bearing in mind that these four years all fell at the time 
of small but not of minimum sunspot activity, it appears 
clear that we have here brought out a third coronal type as 
distinct and definite — perhaps even more so than those 
which have been already recognized as appropriate to the 
times of actual maximum and minimum ; and it may be 
hoped that we have now material enough to enable us to 
trace the course of change which the corona undergoes in 
its passage from one extreme form to the other. 

It may be opportune here to correct a widespread mis- 
apprehension, that minimum coronaj are small and faint 
except for the two great equatorial rays. The reverse 
would seem to be the case, except in the immediate 
neighbourhood of the sun's pole. The corona, for instance, 
of 1878, so far from being small and faint, was unusually 
large and bright ; and the present one, though we have not 
yet reached the actual minimum, possessed the same 
characteristics. 

The feathery structure round the solar poles, which was 
so plainly seen in the eclipse of 1878, and which has been 
recognized more or less clearly at so many eclipses since — 



50 



KNOWLEDGE. 



[Makch 1, 1808. 



especially at or near the time of minimum — was very 
apparent on the present occasion. 

The photographs of the corona have been unusually 




The Sun's Corona, Total Eclipse, January 22nd, 1898. 

numerous, and have been taken on every variety of scale, 
from a diameter of a single millimt'tre with a hand camera, 
up to one a hundred times as great. The latter were 
obtained at three stations ; by the Astronomer Royal at 
Sahdol, with an aperture of nine inches and an enlarging 
lens ; by Dr. Copeland, at Gogra, near Nagpur ; and by 
Prof. W. W. Campbell at Jeur, with telescopes of about 
forty feet focal length. Next in order to these giant 
photographs come the standard instruments of the Joint 
Eclipse Committee, with their twin cameras giving images 
of an inch and a-half, and of six-tenths of an inch. These 
were employed by Prof. Turner at Sahdol, and Captain 
Hills at Pulgaon. The cameras taking photographs of one 
inch in diameter and smaller were much too numerous 
to recount ; but special note should be made of Prof. 
Burckhalter's device for obtaining both the inner and 
outer corona on the same plate by means of a revolving 
screen worked by a spindle passing through a hole in the 
centre of the plate, which diminished the exposure given 
to the bright central regions of the corona so as to bring 
it more in accord with the faint light of the outer 
extensions. 

At the extreme ends of the line of stations a novel 
experiment in coronal photography was attempted. At 
Buxar, on the Ganges, and at Viziadrug on the coast, 
a kinematograph was employed so as to obtain a con- 
tinuous series of photographs of the progress of the 
eclipse. The former instrument was supplied by Mr. 
Nevil Maskelyne, and was worked by the Rev. J. M. 
Bacon, the astronomer in charge of one of the two parties 
organized by the British Astronomical Association, and 
the other was in the hands of Lord Graham. 

Of direct visual spectroscopic observations there were 
few. Mr. NewaU and myself endeavoured to trace the 
distribution of coronium — that is, of the substance which 
shows its presence in the 1474 K line ; but the line was 
faint, and it could only be ascertained that it showed a 
general conformity to the shape of the brighter part of the 



inner corona, without its being possible to ascertain 
whether it corresponded in minuteness of structural detail. 
No rifts were detected in it. 

The photographs of the spectrum claim the highest 
interest, and these were of unprecedented number and 
value. Captain Hills, at Pulgaon, with two great slit 
spectroscopes, obtained records of the "flash," both at 
commencement and end of totality, which give a complete 
history of the spectroscopic changes seen in the various 
strata of the sun, from its ordinary spectrum up to that 
of the prominences at Viziadrug on the coast. Mr. Fowler 
and Dr. Lockyer were equally successful with prismatic 
cameras of six inches and nine inches aperture, whilst 
smaller spectrographs of extreme beauty, and ranging from 
C in the red far into the ultra-violet, were secured by 
Mr. Evershed at Talni. 

The examination and interpretation of these photo- 
graphs will be the work, not of days and weeks, but of 
months, and possibly years ; but we may confidently look 
to them for a complete answer to many questions which 
are engaging the attention of solar physicists at the 
present time, and particularly for information as to the 
exact /()('((/(■ of the absorbing vapours which give rise 
to the Fraunhofer lines. Sir Norman Lockyer's theories, 
in particular of dissociation in solar and stellar atmo- 
spheres, will be put to the severest test, and our know- 
ledge of solar mechanism can hardly fail to receive a great 
advance. 

One inquiry which it was hoped the present eclipse 
would advance has failed to meet with success. Mr. 
NewaU was endeavouring to ascertain if the spectrum of 
the corona, as obtained from the two opposite Umbs of the 
sun, gave any evidence of relative motion in the line of 
sight due to rotation. It will be remembered that in 1893 
M. Deslandres came to the conclusion that the corona 
rotated in essentially the same period as the photosphere. 
Mr. Newall had arranged an exceedingly beautiful instru- 
ment for this purpose — a spectroscope, the collimator new 
telescope of which was parallel to the polar axis. The 
spectroscope was also provided with a double slit, the one 
slit tangential to one limb, and the second to the other 
limb ; the one slit stretching from the sun's equator 
northward, the other from the opposite end of the equator 
southward. The experiment, which abundantly deserved 
to succeed, was, however, frustrated by the faintness of 
the coronal spectrum. 

Of other observations it is scarcely possible to speak as 
yet. It should, however, be added that the polariscope, 
which has been almost forgotten in eclipse work for the 
last fourteen or fifteen years, was very successfully used, 
both at Sahdol and at Pulgaon, and the clearest indications 
were secured of strong radial polarization. 

Such is a very brief outline of the principal results (so 
far as we yet know them) of this the most completely 
successful eclipse on record. We hope to be able, at no 
very distant date, to go much further into detail, when 
some portion of the photographs obtained have been deci- 
phered and discussed. 



BRITISH BEES.-I. 

By Fred. Exock, f.l.s., f.e.s., etc. 

THE number of species of bees in Great Britain is 
by no means large — only just over two hundred — 
and yet to those people who, " having eyes, see 
not," this small number is far too large for insects 
which possess stings. Gardeners, too, look upon 
them as marauding thieves, and this in spite of the fact 



March 1, 1808.] 



KNOWLEDGE 



51 



that fertilization of plants is brought about by the 
unceasing industry of the bees. 

Ungratefulness in man is so common a characteristic 
that we must not be surprised to find that so little interest 
is taken in the study of our British bees. It is sufficient 
for the majority to know that " bees make honey." 

For those who (/" desire to be soothed by the humming- 
bee, or to follow out the habits and economy of our British 
bees, the choice of books on the subject is by no means 
a large one. They are; "Bees of Great Britain," by 
Frederick Smith ; Shuckhard's " British Bees " ; and the 
most valuable work, " The British Apidffi," by Edward 
Saunders. Mr. Saunders is always ready and willing to 
help young students in naming their captures. It is one 
of our greatest pleasures to look back upon the many 
instances of kindness received from the late Frederick 
Smith, who was in every sense a true lover of bees — one 
who would inspire enthusiasm in the heart of a young 
beginner. The collection of British bees at the Natural 
History Museum, South Kensington, was under his affec- 
tionate care years ago at the British Museum. 

The first family, the Anilnn'uhr, is divided into two sub- 
families ; the first composed of two genera only, possessing 
tongues much like the Vespidie, obtuse and rounded ; that 
of Colletes being very beautiful when fully expanded 
(Fig. 1, Collcfcs l)avic>i(inii). There used to be a very 
large colony of this species at Farnborough, where I have 
seen hundreds of the burrows close together in the sand- 
banks. In some of the woods near Aldershot there were 
also a number of colonies, many of which appear now to 
have become deserted. The exceedingly neat looking 
species, C. sucfincta, I used to find at Ilampstead Heath, 
but, like other things, it has now disappeared from that 
neighbourhood. The bees of this genus have exceedingly 
sharp and powerful stings, and the legs are clothed with 
most beautiful hairs of varied form. 

The members of the other obtuse-tongued genus, 
Prusopis, are all small in size and more or less black. 

They are exceeding- 
ly fond of the flowers 
of the vetch. The 
males are most dili- 
gent in their pursuit 
of the females. 

The second divi- 
sion, in which are 
classed those bees 
possessing tongues 
more or less acute, 
is composed of a 
number of genera. 
Like those of the 
first part, the mem- 
bers of these genera 
are solitary in their 
habits. The females 
burrow into the sand for some considerable depth, and 
line the sides of the burrow with an exceedingly fine mem- 
brane, resembling goldbeaters' skin — only considerably 
thinner. 

The bees belonging to the genus Sphecodfs are small, 
measuring from three-eighths to half an inch long. They 
have black heads and bright, shining red bodies. They 
are fond of settling on the bare patches of sand at 
Hampstead and in other places where they are tolerably 
plentiful, the females being more so than the males. 
The sculpture of the thorax is well worth examination. 

The next genus, Halutus, is composed of many species, 
of some which are very small, but all are exceedingly 




Fig. 1. — CoUeles Daviesana. 



neat in their appearance. Both sexes of many species 
appear in September, when, after impregnation, the females 
hybernate, and make an early appearance the following 
spring, when they are busily engaged forming burrows in 
the sand. Many species are very fond of the flower of the 
dandelion, and may frequently be found curled up asleep 
in a half-closed flower. A close watch on these and other 
flowers during the early hours of the day will often be 
rewarded by good captures. The tongues of all the 
Halicti are long and lanceolate, and require great care 
and patience to expand and set out so that all the exquisite 
structure may be revealed. 

We next turn to the genus Anihemt, which contains the 
greatest number of species both rare and beautiful. In 
this genus are the bees which herald the approach of 
spring. Many of them visit the opening catkins of 
the willow, and, like the Lepidoptera, soon become 
intoxicated, and fall an easy prey to the first prowling 
naturalist. It is, indeed, a glad time when, after 
weeks of cold and foggy weather, the bright sun 
breaks out, bringing with its genial warmth these pretty 
brown bees, each one arrayed in such a perfectly fitting 
costume of plumed hairs, and their delicate wings glinting 
in the sunshine — for bees must have bright sunshine to 
enjoy their lives to the full. I have often heard the 
remark that it is not much or any use going out in search 
of bees before nine o'clock in the morning. This was 
specially impressed upon me when receiving directions 
as to how, when, and where to look for that most extra- 
ordinary parasite Stijhips, which is found in the abdomen 
of several of the AwlnncE; but having formed some 
original ideas concerning Stytops I am afraid I quite 
disregarded most of my friend's instructions. Instead 
of nine o'clock, I was on the ground before eight — 
waiting for the bees — and as they seemed to be rather 
behind time I commenced to search for their burrows, 
which, after a little experience, I was enabled to detect by 
noting the disturbance of a few grains of sand. By 
quickly inserting the bent end of my digger (an old half- 
round file) a short distance away from the burrow, I was 
able to heave out in nine times out of every ten the 
Andrena, with the moisture clinging to its still yet untried 
wings. Its astonishment at being so unceremoniously 
" lifted " appeared to deprive it of the power of sudden 
flight, and before it could recover it was under close 
examination, and if stung by Stylops it was boxed at 
once. I placed many of these " stylopized" Andn-na- in 
various parts of Hampstead Heath, hoping to establish 
the parasite in parts somewhat remote from the area so 
dear to the holiday makers during Easter (the time 
when many species of Andn-na are most plentiful), but 
Hampstead Heath has, within the past twenty years, 
considerably altered its appearance. Where there used to 
be rising sandbanks, the head-quarters of endless bees 
and sand wasps, there is now an unsightly cinder path 
crossing the very spot which was once the citadel of these 
beautiful bees, and where, in July, could be seen dozens 
of the burrows of the sand wasps, ('erceris (Hiiimia and 
ornata. Last year I visited this locality several times, 
but not a single Veneris did I find. The beautiful Andremi 
fulva, with its bright chestnut-coloured abdomen, has not, 
I am rejoiced to say, yet been exterminated, though how 
long it will be able to exist time alone will show. Its 
bright colour is too tempting to the sharp eyes of Easter 
Monday Cockneys. Fig. 2 shows the head and mouth 
organs of Andrena fulra, which, together with others of 
the genus, burrow deep down into the sand, throwing up 
quite large heaps, which frequently are trodden flat to the 
ground when the industrious female is out collecting pollen 



52 



KNOWLEDGE. 



[Makch 1, 1898. 




Fig. 2.—Amlreitafiiha. 



and nectar. On her return there is no sign of her home, 
but she, possessing the bump of locahty to a large degree, 
sets herself to work to find or make an entrance through 
the hardened sand. This she proceeds to do by removing 
the sand with her powerful mandibles, which are frequently 
worn down until they are made stumpy in her efforts to 
reach her burrow — efforts terminating in success. 

The male of A. 
fulva has its man- 
dibles enormously 
developed. Some of 
these bees, on first 
emerging from their 
burrow, are exqui- 
sitely arranged and 
exact in every fringe 
of hairs, on head, 
abdomen, and legs. 
One of the neatest 
is Anilreiin fulvimis, 
which is markedly 
common at High- 
gate Cemetery — a 
good locality for 
many kinds of bees, 
where they can live and die in peace. The neighbour- 
hood of Highgate Archway, too, used to be a noted spot 
for uncommon AnJrfna, such as A. hinijipes : but now it 
sounds like mockery to mention such localities as Copen- 
hagen " Fields " and Highgate " Fields." 

Leaving the Andrence, we now come to a bee, ^^llC)■opix 
hihiata, of which, when the late Mr. Fred. Smith wrote his 
" Bees of Great Britain," in 1855, only three specimens (all 
males) were known to exist. The first captured in this country 
found its resting place in the British Museum ; the second 
was taken by Mr. Walton in the New Forest ; and Mr. 
Samuel Stevens captured a third at Weybridge, on July 
4th, 1842 ; and though the surrounding country had been 
searched year after year, it did not yield another specimen. 
Not until the year 1878 was this rare bee heard of again, 
but then the well-known hymenopterist, Mr. Bridgman, 
appeared at the right time and right place to find both 
males and females. In 1882 I went to Uve at Woking, 
which was then a comparatively small place. At that 
time I used to wander about without interference, and 
I could revel in studying insects, especially bees. Previous 
to taking up my abode at Woking a microscopist asked 
me what I was going to take when I got there. I 
immediately replied, " Oh, Macropis," adding, " 1 will 
write and let you know immediately I capture it." 

In the following 
■July I observed 
large quantities of a 
flower somewhat 
new to me, upon 
which I kept con- 
stant observation — 
having a presenti- 
ment that I should 
find ]\[(icropis upon 
or about it. On 
July 27th, 1882, my 
valued friend, the 
late Sir Sidney 
Smith Saunders, 
paid me a visit, and 
we both went out 
" beeing." At noon exactly I noted a bee pass by whose 
hum I did not know, so I waited until it should return. 




which it did in a few minutes — little suspecting that it was 
doomed to be captured, by a rapid stroke from my arm. I 
quickly removed it from my net and brought my magnifier 
to bear ; I then called to Sir Sidney to come and have a 
look at something, asking, as I gave it into bis fingers, 
" What's thot :' " when after a few moments' pause Sir 
Sidney almost shrieked with excitement, " Why, it's 
Macroph ! " I boxed it safely, feeling that my presenti- 
ment had indeed come true. 

After this piece of fortune Sir Sidney and I were 
much excited, and jumped hither and thither like parched 
peas ; but all in vain that day — no more Macropis 



Fig. Z.-CilU 



hcemorrhoidaUs 



On the 29th I was found on the spot with eyes and ears 
at full cock ; my patience was rewarded by capturing four 
more male and one female Maempis. I quickly discovered 
the fact that the latter knew how to sting. After my first 
capture 1 sent a card to my friend, informing him that " I 
had got Macropis." 

Sir Sidney S. Saunders and I had several rambles 
together in search of this beautiful bee, and each was 
rewarded by capturing several males and females. The 
following year, 1883, I saw dozens of both sexes, which I 
left to be fruitful and multiply. I searched in vain for 
their burrows, though I tried all kinds of dodges. Catching 
some, I gently tied a delicate piece of fine silk to one of the 
legs, then a small piece of white tissue paper, and started 
the bee flying. I followed the bees long distances, but all 
my efforts were futile. Some of the " rims " ended by my 
catching my foot in a twig and falling headlong into a 
gorse bush, from which I was glad to retire as soon as 
possible. Woking has since increased to five times the 
size, and some of the best parts of the common are utterly 
ruined. 

Another beautiful bee which I used to find occasionally 
in the neighbourhood of Woking was ' 'ilissa hcBmorrhoidalU, 
which affects the flowers of the harebell — another 

flower that is not so plentiful as in years past, but one 

absolutely necessary to this bee — one of the most energetic 

and businesslike insects with which I am acquainted. 

Quick eyes and hands are needed to capture this prize, for 

it only appears in the hottest sunshine, when everything 

must be ready for 

its reception. It 

announces itself 

without a moment's 

hesitation, and does 

not tarry long, for it 

is no sooner in one 

harebell than it is 

out again and away 

— except, indeed, 

when the net follows 

up as quickly. Even 

when it is in the net 

the capture is not 

complete, for this 

bee does not sham 

death as do others, 

but bustles about in 

a mostvigorous manner in its endeavours to escape, stinging, 

too, in the most approved style. I do not think any bee 

possesses such an exquisitely beautiful tongue as this one. 

In outward appearance this bee is much like a large honey 

bee, though much more hairy. Fig. 3 gives an idea of 

the head and tongue. Whilst searching for Cilissn I used 

occasionally to find a few of that grand bee, Dasypoda 

hirtipes — the hairy bee — without doubt the most beautiful 

and graceful of all British bees. It has only once been 




Fig. 4. — Dasypoda'hirfipes. 



Mabch 1, 1898.] 



KNOWLEDGE. 



53 



recorded from the London district — July 18th, 1878 — when 
I was fortunate in capturing a fine female specimen as it 
hovered about the face of a sandbank on Ilampstead 
Heath. Ptixi/iioda Itirti/iis is intensely fond of composite 
llowers of the dandelion type, among the petals of which 
it buries itself as it rilles the flower of its nectar and yellow 
pollen, with which it becomes heavily laden. Its immense 
bushy hind legs look like bright yellow bottle brushes. 
The shape of the 
hairs on the third 
pair of legs is unique 
among bees, each 
tiny little branch 
being surmounted 
by a knob or club. 
This bee is plenti- 
ful along the south 
coast. I found them 
just emerging from 
their burrows in the 
sand at Littlehamp- 
ton. Fig. i shows 
the peculiar shape 
of the tongue and 
maxillae. 

Paimrijus is the nest in order. In colour it is a smoky 
black. It is fond of making its burrows in hard paths, 
and in such situations I have found them at Woking and 
Hampstead, besides having swept them up from flowers 
of the mouse-ear hawkweed, which used to flourish on 
Hampatead Heath. 

The genus Nomadii consists of a number of species, more 
like wasps than bees, with bright yellow-banded bodies. 
All are cuckoo bees, depositing their eggs in the burrows 
of AndrenidcB at the time when the rightful owners are 
engaged storing up pollen for their progeny, which are 
starved out by the stronger larvae of this cuckoo bee. The 
tongue is a very neat one, more resembling that of the 
honey bee {see Fig. 5). 

The prettily marked bee Epeolus raiieijutus is parasitic in 
the cells of Colletes Darii'sana. It has a particularly sharp 
sting. {To be coHtiinwd,) 




FlO. 5. — Namada succincta. 



THE VINEGAR EEL. 

By C. AiNSWORTH MiTCUELL, B.A,, F.I.C. 

IN the " Philosophical Essays " of Eobert Boyle, 
published in 1661, there occurs the following 
paragraph ; — " We have made mention to you of 
a great store of living creatures which we have 
observed in vinegar ; of the truth of which observa- 
tion we can produce divers and severe witnesses, who 
were not to be convinced of it until we had satisfied them 
by ocular demonstration ; and yet there are divers parcels 
of excellent vinegar wherein you may in vain seek for 
these living creatures, and we are now distilling some of 
that liquor, wherein we can neither by candle-light nor by 
daylight discern any of these little creatures, of which we 
have often seen swarms in other vinegars." 

This appears to be the earliest reference in scientific 
literatiKe to the Leptodcra oxopliihi, which, from its shape 
and fondness for vinegar, has long been known as the 
"vinegar eel," and which in Schneider's opinion is iden- 
tical with the " eels " which may often be observed in 
sour paste. 

It is of very frequent occurrence in certain vinegar 
works, more especially on the Continent, where the 



vinegar is manufactured at a lower and (for the eels) 
more favourable temperature than is usual in England. 
As to its origin, nothmg is definitely known, though 
Czernat is inclined to think that it is introduced in the 
water used for brewing the vinegar. Occasionally, on 
allowing vinegar to stand exposed to the air for several 
days in warm weather, it will soon be swarming with 
these minute creatures, which have probably developed 
from germs already present in the liquid. As wiU be 
seen from the figure, which shows a single vinegar eel 
under a high power, it is of very simple construction. 

The body is cylindrical and ends in a sharp point, and 
the skin (which is changed from time to time) is smooth, 
structureless, and very strong. According to Czemat's 
average measurements, the length of the male's body is 
about one twenty-fifth of an inch, that of the female one 
sixteenth of an inch, the relative proportion generally being 
as 1 : 1-3. In both sexes minute corpuscles may be 
observed, which are put in motion by the contraction of 
the body. In the female the eggs lie in two tubes which 
unite in one opening. 

Vinegar eels are capable of moving either backwards or 
forwards, and progress by alternately shaping themselves 
iiito an S and straightening out again. They appear to be 
incessantly darting through the vinegar at the top of their 
speed in all directions, but always with a tendency towards 
the surface, as they are air-breathing animals. Czernat 
states that they never rest day or night, and that their rate 
of progress is about one inch in twelve and a-half seconds. 

They are capable of living in very dilute alcohol or 
acetic acid as well as in vinegar, and can withstand a 




The Vinegar Eel (higlily magnified). (After Pasteur.) 

great variation of temperature, not being killed until the 
temperature reaches one himdred and forty degrees to one 
hundred and fifty degrees Fahrenheit in one direction, and 
about ten degrees below the freezing point of water in the 
other. 

Pasteur was the first to point out how harmful the 
vinegar eel is in the manufacture of vinegar. Vinegar is 
prepared by causing certain micro-organisms (of which there 
are several species classified under tbe term of "acetic 
bacteria ") to act upon a liquid containing a small percentage 
of alcohol, such as beer, fermented malt extract, or cider. 

By the action of these bacteria, which are supplied with 
the requisite amount of atmospheric oxygen, the alcohol 
is gradually converted into acetic acid, the process being 
accelerated by maintaining a temperature of about one 
hundred degrees Fahrenheit within the "acetifier." 

When insufficient- air is supplied, the bacteria form them- 
selves into a slimy layer on the surface of the liquid, 
popularly known as "mother of vinegar." Should, now, 
vinegar eels develop in vinegar iu the course of manufacture, 
they multiply rapidly, and a struggle for the air supplied to 
the apparatus commences between them and the bacteria. 
For some time a working balance may be struck between 



54 



KNOWLEDGE 



[March 1, 1898. 



tbem, and the air shared ; but during this struggle, which 
may last for weeks, the activity of the bacteria is impaired, 
and though the conversion of alcohol into acetic acid still 
proceeds, it does so with an increased expenditure of time 
and a reduced yield. Should the vinegar eels gradually 
obtain the upper hand, they interfere more and more with 
the working of the apparatus, and eventually the conversion 
of alcohol into acetic acid comes to a standstill. If, on the 
other hand, the bacteria get the mastery, they form the 
slimy layer, mentioned above, over the surface of the 
liquid, as the result of their obtaining insufficient oxygen. 
This skin effectually prevents the eels from breathing when 
they come to the surface, and so they perish for want of 
air, and fall to the bottom of the apparatus, where they 
may accumulate and putrefy. In either case the only 
remedy is to thoroughly clean and disinfect the apparatus 
and commence afresh. 

It was only with great difficulty that Pasteur could 
convince certain French vinegar manufacturers as to the 
advantage of endeavouring to get rid of the vinegar eel, for 
so general had it become with them that they had begun 
to look upon it as an essential part of the process instead 
of a deadly enemy. 

Even after vinegar containing eels has been freed from 
them by filtration the germs remain, and when placed 
under suitable conditions will develop into eels, which will 
rapidly multiply and cause the vinegar to become turbid, 
although it has been recently proved in (iermany that they 
do not aiJect its strength. As Pasteur was the first to point 
out the ill effects caused by the vinegar eel in the manu- 
facture of vinegar, so, too, he was the first to devise an 
effectual means of destroying them, with their germs and 
all other forms of life in the finished product, by heating 
it to about one hundred and sixty degrees Fahrenheit, 
and then rapidly cooling it so as to prevent loss of the acid 
by evaporation. And this is only one of the many instances 
in which the studies of Pasteur on micro-organisms have 
been of practical benefit to mankind. 



BOTANICAL STUDIES.-II. 
COLEOCH^TE. 

By A. Vaughan Jennings, f.l.s., f.g.s. 

IN a preliminary study' we examined a common 
fresh-water alga which showed in its simplest form 
the process of oogamous reproduction ; the develop- 
ment of a single egg-cell in a simple protective case, 
fertilized by motile antherozoids formed in an 
adjoining chamber growing out from the same plant- 
filament. Apart from structural details of the plant in 
question, attention was specially called to two points in 
connection with its reproduction : firstly, that what might 
be termed the "fruit" was only the fertilized egg-cell 
surrounded by a thickened wall ; and, secondly, that on 
germination this " fruit " (or oospore) grew at once into 
a new plant, in all respects resembling the parent. 

Our next illustration may also be taken from the fresh- 
water algip, and from a genus by no means uncommon in 
this country, though not, perhaps, easy to find without 
some careful observation. 

On the stems of water plants such as the water-lily and 
the common pond-weed, or on the glass sides of aquaria, 
may be found little green discs ranging in size from almost 
invisible specks to circles a quarter of an inch or so in 
diameter. 



* Vaucheria, KxowLEDGB, January, 1898. 



These belong to the genus Coleochmte* a well-defined 
and widely distributed genus containing in this country 
some three species. The plants are, it is true, very 
frequently sterile, but the nature of the reproductive 
process is of considerable importance in the line of study 
we are following. 

It will be interesting, however, first to examine the 
structure of the plant itself. If the species collected is, 
as it most probably will be, either C. scutata or Corhkularit, 
it will be noted that the whole plant is just a flat plate of 
cells arranged in radial rows ; the cells all in one plane 
and never superposed one above another. As the cells 
have all a fairly uniform average size, this must mean that at 
the growing margin many cells divide in two by radial 
walls, and numerous instances of this will readily be found. 
In another species — C. sohitu — the rows of cells are, in 
fact, separated for a considerable portion of their length : 
while in others, such as ' '. pulfinnta, the cells are no longer 
in one plane, but grow up straight or obliquely, forming a 
sort of cushion. 

In other words, we have within the genus t a series of 
stages connecting the flat ceU-plate with the tree-like 
growth of such types as BuUiochatt, one of the most 
beautiful of our fresh-water alg». Among the red sea- 
weeds, also, the early stages of some species of the 
"coralline" Melulu'sia have a similar structure, and the 
delicate discs of cells may often be found on the surface 
of the larger weeds. A similar growth-type occurs also 
on leaves in tropical countries, constituting the genus 
Plii/C(tpeltis,\ but here a yellow colouring matter is present 
as well ; and this fact, together with its reproductive 
organs, shows it to be allied to the little yellow or red 
filamentous algic of the genus ('hroiilepus (or TrenUpuMia) 
which occur on rocks and trees all over the world. We 
have, that is to say, similar or parallel types of growth in 
plants which are otherwise widely separated. Some 
writers seem to regard the disc type as derived from the 
thread-like form ; but the early stages in development of 
such forms as Phycoprltis seem, as I have elsewhere 
suggested, i to point to an opposite conclusion. Theoretical 
questions such as this are, however, outside our present 
purpose. 

Coming to the question of the mode of reproduction in 
('ohochate, -we find, as in Vuticheria, th&t there are two 
distinct methods. In the first case the protoplasm of some 
of the cells of the thallus becomes contracted and rounded, 
and finally escapes by an opening in the cell wall. When 
liberated it appears as a free-swimming ^ovipmiilium with 
a pair of long cilia. This, after a period of activity, loses 
its cilia, settles down, and subsequently grows into a new 
plant. The process is therefore physiologically similar to 
the escape of the more complex :oin/o)iiilium of Vaticheria, 
and has nothing to do with the formation of a true fruit. 
It is again a case of " rejuvenescence " of a protoplasmic 
particle without any combination with other elements. 

In the second case the contents of certain cells become 
enlarged and specialized to form an orisphen, while some 
of the other cells divide in four, and from each new cell 



* The name refers to the long bristle-like hairs ivitk a sheathing 
base whicli occur on the cells of the disc in most species, but are 
sometimes altogether absent. 

t The closely related genus Aphanochate, which also occurs on 
ftesh-water weeds, shows in the same war an intennediate condition 
between the discoid and the iilamentous growth. 

:J: The Mi/coidea parafitica (Cunningham), which causes disease 
on the leaves of the coffee and other plants, is nearly related, but 
may consist of more than one cell-layer, and may penetrate the 
tissues of the leaf it grows on. 

§ Proceediigsofihe Boi/a' IrM Academy, 1895. 



Mabch 1, 1898.] 



KNOWLEDGE 



55 



thus produced aet free an antluTozohl. This is a free- 
swimming body with two ciha, similar to the zoogonidia, 
but smaller, and it reaches and fertilizes the oosphere by 
different methods in the various species. In the common 
British species it appears that any cell of the disc may 
enlarge and become an oogonium ; and, similarly, other 
cells may divide and become antheridia, though often on 
separate plants. The fertilization of the oospherea by 
the antherozoids in these cases apparently takes place by 
the passage of the latter through an opening in the cell 
wall of the oogonium. 

The process has been studied in detail by Pringsheim in 
the case of a species which is not found in this country — 
Coh'ochat,- /nihinntd (A. Br.) — and in this case the highest 
degree of specialization seems to be reached. The species 
is one of those already referred to as having a half-fila- 



function to the sti/U of a flower, and is a special structure 
developed in connection with the process of fertilization. 
Its presence in this one type of fresh-water weed is specially 
interesting, because it is a characteristic organ in the case 
of the red seaweeds, though in these the fertilizing agents 
are non-motile bodies or pollinoids. 

This similarity between the reproductive process in 
Coleochivte and in the red seaweeds is still more marked in 
the subsequent stages. After fertilization not only does 
the oosphere enlarge and become surrounded by a cellulose 
wall (constituting an oospore or oosperm), but some 
physiological influence extends to the adjacent cells, causing 
them to divide and grow up round it, enclosing it in a 
protective cellular layer or perirarp. 

The structure thus formed— which has been called by 
different authors a ciirpoijonium or spermocarp — is therefore 




A — Young plant of Cohochcefe sciifafa (Brcb), magnified about one hundred times. In the upper part some of the 
cells are dividing into four previous to the development of antherozoids. B. — A fertile filament of C. puleinafa (A. Br.), 
showing the oosphere enclosed in the oogonium with its trichogyne {t). Below are the antheridia {a) and above an 
antherozoid (a') . c. — An oogonium in same species after fertilization, showing the surrounding pericarp (p). d, — The 
spermocarp liberating its carpospores. E. — Zoospores formed from the earpospores. (b to E, after Pringsheim.) 



mentous, tufted growth, and here the oogonia are terminal 
on the ends of the threads. 

The oogonium is, as before, only an enlarged 'and 
specialized cell containing a single oosphere, but its wall 
is prolonged into a long tubular projection termed a 
" trichogijiu." Antheridia are developed from adjacent 
cells in this species, but in some other cases on separate 
plants. 

There is no doubt that the trichogyne corresponds in 



* The species is not uncommon in the lake* of Central Europe. 
I am indebted to Prof. Oltmanns for caUing my attention to it on 
plants of IsoHes in the Titisee, near Freiburg-in-Baden. 



a very mnch higher type of fruit than the simple oospore 
of Viiuclieria. 

The fruit remains quiescent during the winter, but in 
the next spring the oospore divides and forms several cells 
or citrpoapoi-es : it does not itself grow into a new Cohochcete 
plant. Fm-ther, the carpospores themselves do not grow 
mto new vegetative plants. They liberate free-swimming 
zoospores, and these in their turn give rise to new (.'oho- 
chceif plants which may reproduce themselves again by 
either method. 

WhUe, then, an ordinary sterile plant of CoL-ochate does 
not show us any particular advance in general structure 
from many of the lower ThiiUophijta, there are certain well- 



56 



KNOWLEDGE 



[Maboh 1, 1898. 



defined features in its life history which mark a great step 
in the evolution of plant life. Firstly, there is the 
development of the trichogyne. Secondly, there is the 
influence of the process of fertilization on cells adjacent to 
the egg-cell, resulting in the formation of a fruit. Thirdly, 
there is the all- important phenomenon of the division of 
the carpospore into a group of cells which do not imme- 
diately reproduce the parent plant. 

We have here, in fact, a very early indication of that o/icr- 
nation of >i, nriKtinns which has played so important a part 
in the story of plant life, and a study of which has given us 
the clue to the relationship between the lower and higher 
members of the vegetable kingdom. It is here that we 
see clearly for the first time, in the upward succession of 
plant types, the distinction between an oiijihyte or egg- 
bearing generation and a sporojihyti or spore-bearing gene- 
ration, arising from it and in turn reproducing it again. 

Some of the consequences of the increasing differentia- 
tion of these alternating stages and the speciahzation of 
their accessory tissues will be pointed out in later studies. 



CLOUD BELTS. 



By Wm. Shackleton, f.r.a.s. 

ANYONE who has made a voyage beyond the 
Equator will, no doubt, retain a good recollection 
of a day or so of disagreeable, oppressive, damp 
weather, when moisture seemed to be exuding 
from all sides, just as if one had come out of a 
dense Scotch mist, and everything was coated with a thick 
film of moisture which trickled down in great beads. 
This journey through the watery-laden atmosphere and 
almost constant rain, is really a passage through the 
equatorial cloud belt which girdles the planet on which we 
happen to be located ; and although we may admire Jupiter 
with his many cloud belts as seen through a telescope, yet 
we feel thankful for the invention of steamships which 
enable us to leave behind as quickly as possible the most 
marked cloud-belt appended to our earth, rather than be 
becalmed in these " doldrums " where ships have been 
known to drift listlessly about for whole weeks. 

A graphic description of the kind of weather which is 
usually experienced under the cloud ring of the equatorial 
calm belt is found in the journal of Commodore Sinclair, 
kept on board the U.S. frigate Congress during a cruise to 
South America in 1817-18. He crossed it in the month 
of January, 1818, between the parallel of 4- N. and the 
Equator. He says :— " This is certainly one of the most 
unpleasant regions on our globe. A dense, close atmo- 
sphere except for a few hours after a thunderstorm, during 
which time torrents of rain faU, when the air becomes a 
little refreshed ; but a hot glowing sun soon heats it again, 
and but for your awnings and a little air put in circulation 
by a continual flapping of the ship's sails it would almost 
be insufferable. No person who has not crossed the region 
can form an adequate idea of its unpleasant effects. 
Except when in actual danger of shipwreck, I never spent 
twelve more disagreeable days than in these calm lati- 
tudes." 

The general appearance of the sky in this " rainy sea," 
as it has been called, is a steamy haze — sometimes growing 
into uniform gloom, with or without heavy rain, at other 
times gathering into small ill-defined patches of soft 
cumulus. After dark there is always a great development 
of sheet lightning till about two in the morning. 

The Plate shows the appearance at the edge of the cloud 
belt on the confines of the south-east trade wind, and is 
reproduced by the kind permission of Sir J. Benjamin 



Stone, ]\I.P., from a photograph taken by him in 1894, on 
his way to South Africa. 

Besides this equatorial cloud belt, however, there are 
two other rings encircling the earth, where rain falls 
perhaps more incessantly even than in the equatorial 
belt itself, though by no means in such large quantities. 
These latter belts occur near latitude GO in both 
hemispheres ; and perhaps more of us have passed through 
these than that of the equatorial belt, especially the 
one crossing the Shetlands and South Norway about 
Bergen, where it rains nearly every day throughout the 
year, and which place tourists speak of as especially 
relaxing, thus experiencing some of the effects described 
by Commodore Sinclair. 

It is not necessary to go into detail as to the actual 
cause of these cloud belts — that is a matter for text-books ; 
sufficient it is to say that in the case of the equatorial belt, 
the north-east and south-east trade winds flowing into the 
equatorial regions to supply the up-draught caused by the 
intense heating of the atmosphere surrounding the Equator, 
pass over zones of about twenty degrees in width, from 
which all, or nearly aU, the vapour of evaporation is carried 
into the comparatively narrow zone of the equatorial calm 
belt before it ascends to higher and therefore colder levels. 
In these upper reaches condensation takes place, thereby 
producing a constant canopy of dense cloud which forms 
a nearly continuous cloud girdle. The equatorial calm 
belt, therefore, is also a cloud and rain belt. 

It has been estimated that the daily amount of evapora- 
tion on the ocean within the tropics is about a quarter of 
an inch per day. If, then, all this amount of vapour over 
zones, say, one thousand miles in width on each side, is 
carried into the calm belt, say three hundred mUes in 
width, and is there precipitated as rain, the daily rainfall 
would be 1-G7 inches; and consequently if this belt 
were to remain stationary, we should have an annual 
rainfall of about sixty feet for the average of the width. 
But since the cloud and rain belt oscillates through a 
range generally more than twice as great as its width, 
this amount of rain is distributed in the course of the 
year over a zone more than three times as wide, and hence 
in general less than one-third of this amount falls in any 
one place during the year ; aj., at Maranhao at the mouth 
of the Amazon, and on the border of the cloud zone, the 
rainfaU is two hundred and seventy inches per year, and 
is even greater at several places, but this is chiefly due to 
local influences. 

From certain causes the rain and cloud belt, as it 
exists at any given time, is mostly wider than the belt of 
calms, but of course neither have very definite hmits ; these, 
however, are much better defined over the great oceans, 
where the trade winds blow much more steadily than on 
the continents, where regularity is very much interfered 
with by the various abnormal disturbances of uneven 
surfaces and mountain ranges, and likewise by the 
monsoons of the Indian and other oceans. The rain 
and cloud belt is, however, clearly traceable across the 
whole of Africa, wherever observations have been made, 
as also across the American isthmus ; but it has greater 
width and its Hmits are not so well defined. These cloud 
zones, on which large amounts of rain fall, are traced out 
naturally for us on the surface of the globe, and it has 
been truly said that these regions are the "reservoirs of 
the great rivers"; e.ij., those originating from the equatorial 
cloud belt being the Amazon, Orinoco, Niger, Nile, and 
Congo, whilst the Yenesei, Obi, Mackenzie, and St. Lawrence 
largely derive their supplies from the minor belt in the 
northern hemisphere. 

From certain causes which can be explained, the mean 



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March 1, 1898.] 



KNOWLEDGE 



57 



position of the cloud belt ia not coincident with, but lies 
a few degrees north of, the Equator, and, as has been 
mentioned before, it oscillates over a zone more than 
three times its width in a year. 

The cause of this annual oscillation of the belt is that 
during the winter of each hemisphere the earth's surface 
and atmosphere becomes much colder than it is in the 
other hemisphere, and consequently the atmospheric 
volume is considerably less, and there is a pressure 
gradient above by which the air of the higher strata flows 
from the warmer hemisphere to the colder, L^lving rise to 
a counter flow of air below, from the colder to the warmer 
hemisphere. The conse<juence is that the stronger system at 
this season encroaches somewhat upon the territory of the 
other, causing the middle of the equatorial calm and rain 
belt (which is the dividing line between the two systems) 
to be displaced from its mean position. There is there- 
fore an annual oscillation of the calm and cloud belts, such 
that the most northerly position is in midsummer and 
the reverse in midwinter of the northern hemisphere, or, 
in other words, as the sailors say, " The cloud belt follows 
the sun." 

Wet and dry seasons are thus produced in districts 
which fall within the range of oscillation of the rain-cloud 
belt, where it is well defined and not afl'ected by abnormal 
disturbances, but is somewhat as in the ocean and on 
level countries. Such is the case with the Orinoco and 
great Amazonian basin. Humboldt says : " As in the very 
North the animals become torpid with cold, so here, under 
the influence of the parching drought, the crocodile and 
the boa become motionless and fall asleep, deeply buried 
in the mud. At length, after the drought, the welcome 
season of rain arrives, and then how suddenly is the 
scene changed !" In ponds from which, but a week before, 
the wind blew clouds of sandy dust, tlie reanimated fish 
may be seen swimming about, deciduous trees become 
verdant, and scarcely a week elapses before the plants 
are covered with the larvre of butterflies, the forest is 
murmuring with the hum of insects, and the air is har- 
monious with the voice cf birds. 

The rain at these periods excites the astonishment of a 
European. It descends in almost continuous streams, so 
close and dense that the level ground, unable to absorb it 
sufficiently fast, is covered with one uniform sheet of 
water ; and down the sides of declivities it rushes in a 
volume that wears channels in the surface. In the towns 
many of the houses are built on raised causeways, so that 
the roadway is able to act as a river bed during these 
tropical downpours. Perhaps in some subsequent number 
of KNowLEDtiE we may reproduce a street scene under 
these conditions, with half-submerged carts, floating 
barrels, and a rushing stream carrying all before it. 

The effects of these alternating seasons can readily be 
imagined, and to obviate this — or, rather, to have a supply 
of water for irrigation and other purposes during the dry 
season — some of the provinces in South America thus 
affected are constructing large reservoirs; «.'/., in the 
province of Cearfi they are damming up the end of a large 
valley at Quixada, thus forming a large artificial lake in 
the wet season, which will be distributed gradually over 
the parched land throughout the stcn, or dry season. 

Space will not here permit me more than to point out 
that the most conspicuous features of the members of the 
solar system larger than the earth are their dark belts, 
whilst in the case of those planets smaller than ours these 
bands are scarcely traceable. ^Yhether in this respect the 
earth marks a different condition of things existing on the 
giant planets to that on the smaller ones (which constitute 
less than one-hundredth of the planetary mass) is only ccn- 



jacture ; but one would expect that the appearance of the 
cloud belts on the earth, as seen from some other planet, 
would, on account of the great reflecting power of clouds 
and mists, be not in the form of dark but of bands brighter 
than the general surface. 

Seeing, tjien, that all the large planets are so striated, 
should we not expect the central and largest body of our 
system — the sun — to exhibit these characteristics :' And, 
indeed, it does, for are there not two zones of maximum 
" spotted area " on either side of the equator, along which 
concentrated portions of cloud belts move across the sun .' 
Hence, if we imagine these gregations of umbrae to be 
disseminated as penumbraj along the spot zones, we should 
have presented to us a phenomenon closely resembling 
that of the " cloud belts " of the larger planets. From 
these few considerations it may be gathei-ed that " cloud 
belts " play an important part in the cosmogony of the 
solar system. 



A NEW THEORY OF THE MILKY WAY. 

By C. Easton. 

TOWARDS the end of a previous article on " Richard 
A. Proctor's Theory of the Universe " I suggested 
that, if we confine ourselves to those facts known 
to-day with suHlcient certainty, we can only 
attirm, with respect to the structure of the Milky 
Way, that we there see marked irregularity of details, and 
some traces of a regularity at least partial in the principal 
features of the phenomenon. Before venturing to go a 
little further 1 must sum up the facts and considerations 
on which this opinion is founded. Want of space compels 
me in an article of this kind to direct in some cases the 
reader to the sources of information. 

Now that photographs of the Milky Way are so wide- 
spread, there is no need to insist on the great irregularity 
that we observe (in projection) in the distribution of 
the stars, so long as we confine ourselves to a relatively 
small portion of the galactic zone. It follows, moreover, 
from the evidence of all the results recently obtained in 
the study of the galactic phenomenon, that the manner 
of distribution of stars //( spur, varies, even between limits 
that are relatively large : in this part of space the stars 
are widely scattered, in this other part they are gathered 
together into veritable stellar agglomerations. But, a 
priori, that does not by any means exclude a fairly marked 
regularity of the Milky Way, tdhn as a uhoh-. Suppose 
that the Milky Way has the form of the well-known elliptic 
nebula in Lyra; unless we admit that its borders are defined 
by this figure, and a perfect regularity of distribution 
prevails inside this ellipse, we should see — we being situated 
near the central portion, relatively void of stars — a " Milky 
Way " enclosing the heavens in a fashion similar to the 
one we see in reality. 

Besides, this theory of a Milky Way roughly annular or 
elliptical recommends itself by its simplicity, and appears 
to be the one most widely spread at the present day. 

Nevertheless, if one studies the phenomenon closely, 
there are, in this theory of a galactic ring, several points 
that require explanation. 

We see, it is true, the Milky Way forming a great circle 
round the heavens, but, even apart from the irregularity of 
detail, the galactic light is very unequally distributed on 
the circumference of this ring. The Aquila part is much 
more brilliant than the Monoceros part. This is not 
only seen in the studies made with the naked eye, 
but also in the star gauges ; and it is the case for the 
southern hemisphere as well as for the northern. As for 



58 



KNOWLEDGE. 



[Maboh 1, 1898. 



the general naked-eye aspect, two minutes' study on a fine 
evening in September is sufficient to establish the great 
superiority in brightness of the Milky Way between 
Sagittarius and Cepheus over that between Cepheus and the 
Twins. As for the counts and stellar gauges, Sir William 
Herschel found an average of IGTS stars in his gauges 
about Aquila as compared with 82-5 about Monoceros. 
Celoria found likewise for all stars down to the eleventh 
magnitude in ah equatorial zone of about six degrees 
breadth, ")8-8S3 stars in the region containing the Milky 
Way about 18h., and 43 82ii in the part that the Milky 
Way crosses about Gh.* This is a fact that it is quite easy 
to establish, but whose consequences have not received the 
attention that they merit. 

Unless we admit that we are situated in the centre of 
the ring, but that in the body of this irregular ring the 
stars increase systematically, so to speak, towards a point 
(which is evidently most improbable), we must conclude, as 
was said above, that the sun in the interior of this hypo- 
thetical ring occupies an excentric position, fairly near the 
side where is Monoceros, moderately distant from Aquila. 

But why, then, does the lirciuUh of the galactic zone in 
Monoceros differ so little from that in Aquila ? Evidently 
the Milky Way in general ought to appear larger to us 
the nearer we approach the hypothetical ring, for we could 
not presuppose (and before such an utterly improbable 
thing has been proved independently) that the irregulari- 
ties in the breadth of the zone (any more than the irregu- 
larities of brightness) increase towards a given point in 
the circumference. But at first sight the Milky Way 
appears, on the contrary, larger in the region of the Eagle, 
because of the two brilliant branches, and that is why 
Kant has already placed the sun near to that part of 
the Milky Way where this constellation is found. After 
studying it, however, more attentively with the naked eye, 
and including all the branches, it appears rather broader on 
the majority of charts in Monoceros than in Aquila, but 
the difference is far less than theory would indicate. Is 
this circumstance due to the mode of formation of the 
visual Milky Way itself '? (See my preceding paper.) No, 
for in the paper of Prof. Celoria we find an easy way of 
measuring the breadth of the zone where the stellar density 
is greater than the "average" {" jihi/^icul dutaxy" fi; 
and it follows from one of his tables — Tavola V — that 
for the stars as far as the eleventh magnitude (and 
also for the whole of the fainter stars that W. Herschel 
saw in his great telescope), the Milky Way is consider- 
ably larger in Aquila than in Monoceros, and even 
(particularly for the relatively brilliant stars — 11) that 
the principal branch in the Eagle alone has almost the 
same breadth as the entire Milky Way in Monoceros, where 
the galactic light is, moreover, so feeble. 

This evidently contradicts the hypothesis of a simple 
and continuous ring whose parts are all situated at con- 
siderable distances from the sun. ( Situated in the interior 
of such a ring, we ought to be able to observe a correlation 
between the narrow, brilliant, and well-defined portions on 
one hand, and on the other between the feeble, diffused, and 
broad portions.) The hypothesis that there is a real 
duplication of the Milky Way into two branches at the 
same distance from us, over almost exactly the half of its 



•Sir John Herschel, Outlines; F. G-. W. Stiure, Etudes ; J. T. 
'Enckc, Astroa. Nac/iHchten, XXYL.lSiS.p. 3S6; Houzeau, Urano- 
graphie ; Atlas, Mons, 1878; Easton, Voie Lactee, 1893; Astron. 
Nachrichten, 3270; Plassmaun, Jahresberichte der I'.A.P., Berlin, 
1898; Celoria, Fubbl. del Oss. di Srera, XIII. 

t " Le region! in cui le densita stellari sono piu grandi dcUa densita 
media si possono chiamare regioni lattec." Celoria, ibid., p. 43. 



course, is obviously improbable ; but it is also incompatible 
with tlie reality, for the classic representation of the 
"simple " Milky Way* in Cygnus, Monoceros, and Crux, 
as opposed to the double portion in Crux, Aquila, and 
Cygnus, does not exist. + If we hold to an annular Milky 
Way we are compelled to accept at least lu-n rings, which 
both surround us but at very different distances. The 
nearest ring easily explains the very remarkable circum- 
stance that the fairly brilliant stars — those found in the 
" Bonn Durchmusterung " of about — 0-5 magnitudes — 
are, contrary to the others, more numerous in Monoceros 
than in Aquila, a phenomenon that is repeated under 
another form in the belt of bright stars of Sir John 
Herschel and of (Jould.+ Celoria, moreover, does not 
hesitate to admit " due uiiiJli distinti, ne inai intermtti nel 
loro corso." The stars in the nearest ring are projected on 
the sky following the circle ; Cassiopeia, Hyades, Orion, 
Crux, Scorpius, Ophiuchus, Cepheus, those in the more 
distant ring following Cassiopeia, Auriga, Monoceros, 
Crux, Sagittarius, Scutum, Sagitta. The Italian astro- 
nomer does not venture an opinion as to whether these 
two rings really interlace or are only in projection. 

At the time when Celoria's researches were published 
(in 1878), this theory of two distinct and uninterrupted rings, 
that appeared to explain fairly well the general features 
of the galactic phenomenon, did not so much clash as it 
does to-day with the objection that, presented in this 
form, it is unacceptable because of the structure of the 
Milky Way revealed by drawings, and, above all, by photo- 
graphs. For this reason a single ring (the principal ring, 
for instance, in Sagittarius and Monoceros) cannot be 
imagined but by straining probability ; as for two complete 
rings, they are quite inadmissible. The phenomenon is 
evidently much more complicated even in its principal 
features. 

But is this a reason for throwing overboard the irhole 
of this theory of Celoria's, which rests, moreover, on serious 
observations and deductions '? By no means. It is not 
admissible in its entirety, but may weD be true in part. 

Suppose, for example, that these "rings" of Celoria 
are not "unbroken," nor even complete rings, but annular 
detached segments roughly disposed in two planes — or, 
rather, in a " broken plane " (Strnve) — the grave objection 
that we have just raised ceases to exist, and the system is 
in accord with the results that Celoria and other astro- 
nomers have obtained. 

But, first, here are some considerations of a different 
nature. 

If we imagine the Milky Way to be an assemblage of 
stars and of clusters of stars distributed quite by chance, 
we ought to find in all regions of the galactic zone the 
same characteristics very nearly : these characteristics 
depending on the chance of the projection which should 
manifest itself sensibly in the same manner in all direc- 
tions. The details of the distribution will differ greatly 
in one direction from another, but the general character — 
the type — will depend only on the general conditions of the 
whole ; the limits between which vary the stellar density, 
the volume aud brightness of the stars in different parts 
of the system, the frequency of nebulosities and of opaque 
bodies, etc. — this type will be constant. 

In reahty it is not so in the Milky Way. Those who 
have studied it best, both in its aspect to the naked eye 



* " Theme ' (Cvgnus to Perseus, etc.) " the stream is single." 
Proctor, ilont/ilt/ A'otices, XXX., p. 50. 

t Boeddicker, The Milky Wai/ ; Easton, La Voie Lactee, etc. 
X Celoria, Hid.; Sir John Herschel, Outlines ; U. A. Gould, Urano- 
meiria Argentina, 1. 



March 1, 1898.] 



KNOWLEDGE 



59 



and on photographs, will recognize, I believe, that the 
clun-tiiin- of the Milky Way is not the same iu Sagittarius 
and Scorpius, where brilliant and irregular masses — which 
rather appear to be individually connected with parts of 
the secondary branch (or with its brilliant stars) — alternate 
with dark or poor regions ; in the region of Andromeda, 
Lacerta, and about = Cygni, where an even stream 
runs parallel to the galactic axis ; or in Cassiopeia, 
Perseus, and Monoceros, where the tendency to duplica- 
tion has been noticed in some cases independently by 
Boeddicker, Easton, and Pannekoek ; or in the region 
round Aquila to the west of Altair, where there is arranged 
a series of fairly bright patches. 

A remarkable peculiarity of the general distribution of 
the galactic light between a. and ; Aquibi? and (i Cassiopeia; 
is that in the principal (following,') branch the brightness 
decreases (iradualhj from the interior border to the exterior, 
whilst the secondary (preceding) branch is much more 
uniform. There is only one exception, but that is a 
curious one : between y Sagittic and v Cygni it is the 
principal branch that appears dull, whilst a great brilliant 
patch stretches between /3 and 7 Cygni, on the interior 
border of the secondary (preceding! branch ; it encroaches 
a little on the dark interspace. A small, very brilliant 
patch, a little distant, between x and 68 A Cygni, is 
situated exactly on the galactic axis. 

I will only recall here the well-known argument of 
Sir John Herschel on the ilark spaces with -well-defined 
contours in the midst of a luminous zone (Coal-Sack): a 
similar opening, in connection with a dark, large rift, 
visible to the naked eye, passing between 68 A and p Cygni, 
is found in a dim part of the zone between x Cygni 
and a. Cephei — first drawn, I believe, by Heis. These two 
are the chief. The probability is, in fact, very great that 
we have here veritable holes in a " galactic band or 
stream," fairly shallow, and fairly remote from us. 

We may add that the dark regions which often stretch 
over large spaces, and which sometimes form veritable 
intervals between two luminous streams, and occasionally 
bear the character of fissures in a bed of luminous 
matter (Mr. Kanyard and Mr. Maunder especially have 
drawn attention to these curious dark lines in this same 
magazine ), indicate that in several regions the Milky 
Way is principally formed by a band or layer, relatively 
shallow (which does not prevent another band or clusters 
of stars being possibly projected upon this layer), but 
fairly extensive in longitude and latitude. Sometimes, as 
between 74, 68 A, and p Cygni, a large fissure crosses the 
greatest part of the Milky Way in all its breadth. All 
this does not easily fall in with the theory which only sees 
in the Milky Way agglomerations, wholly chaotic, of stars 
and clusters. 

The very extensive nebulosities, discovered lately by the 
aid of photography, which sometimes envelop an entire 
constellation (Orion, Scorpius), and which are certainly 
related to the stars, furnish also a valuable argument for 
the theory that certain extensive parts of the Milky Way 
are in reality associated, and form each a more or less 
complete whole. 

Thus, I believe, we must come back to this considera- 
tion. In detail, the real distribution of the stars in the 
Milky Way is very irregular. In the grouping of the 
stellar agglomerations there is manifested, however, in a 
certain degree, a systematic distribution. This organiza- 
tion of the stellar matter does not, however, go so far 



» See Knowmdob, 1891, October, December; 1892, May ; 1S93, 
April ; 1894, October ; 1895, January, Februarv, August, Norember ; 
1896, February. 



as to produce a geometrical figure of any regularity what- 
ever—ring, ellipse, or one or more rings, concentric or 
interlaced. 

The undoubted connection between certain stars, nebu- 
losities, and parts of the Milky Way, overthrows the theory 
that the Milky Way is infinitely more distant from us than 
the bright stars. Certain regions of the Milky Way may 
be relatively near us. It follows from the researches of 
Celoria that in all probability the Milky Way in Orion is 
much nearer us than the opposite parts of it. But the 
same conclusion is arrived at for other portions of the 
Galaxy. I believe that " Holden's ellipses " * — stars ranged 
in chaplets. etc. — are not, at least In certain cases, the 
result of optical illusion (see the magnificent photo- 
graphs published in Knowledge, 1891, October and 
December — the region between a, f, and /' Cygni), and 
that the dark fissures sometimes bordered by long ranges 
of stars, and other phenomena of the same nature, are 
undoubtedly real. Whatever may be the reason of these 
strange peculiarities of distribution, it is indeed too difficult 
to imagine that the regions where they are produced are 
at incommensurable distances. 

Sir .John Herschel has already pointed out that the 
"long lateral offsets which at so many places quit the 
main stream of the Galaxy, and run out to great distances, 
are either planes seen edgeways, or the convexities of 
curved surfaces viewed tangent iaJli/, rather than cylindrical 
or columnar excrescences, bristling up obliquely from the 
general level." (" Outlines," j 792.) 

There is nothing, indeed, inadmissible in such trains of 
stars — veritable branches of the Milky Way — lying across 
the interior of our stellar system, and, in some cases, coming 
near our sun. Combining this supposition (which gives a 
plausible explanation of more than one question) with the 
theorv of " segments of a ring," to which Celoria's theory 
might be reduced, we find a system of spirals the most 
simple figure that we can imagine the Milky Way to 
assume according to this train of thought. 

As an analogy from what we see in the heavens, I will 
take, not the nebula of Lyra, but rather the nebula Mess. 
101 Ursae Maj. (Eoberts, " A Selection of Photogi-aphs," 
1894, p. 32 ; also Knowledge, February, 1897, p. 54, Fig. 2), 
or else the celebrated spiral nebula in Cines Venatici, 
Mess. 51 Can. Venat. (Roberts, ihid., p. 30 ; and Know- 
ledge, February, I8I17, p. 54, Fig. 4). 

This analogy also leads us to seek for a central nucleus 
towards which the spirals may be directed. Now there 
is one region in the Milky Way which, it indeed appears, 
may occupy such a position. 

In discussing Celoria's theory we have seen that, to 
explain the more general traits of the galactic problem, 
we might place the sun excentrically in one great ring 
(nearer to the Monoceros border), and inside a smaller 
ring. As the points of intersection of these two hypo- 
thetical rings, inclmed to each other at about nineteen 
degrees, are distant from each other in the heavens about 
one hundred and eighty degrees (Crux — Cassiopeia), it was 
better to imagine the inner ring as fairly small. On the 
other hand, the sun ought to be near that part of this 
small ring which is iu the direction of Monoceros, since 
this region is fairly well resolved into separate stars (see 
my preceding article). If Celoria had made his counts, 
not along the equator, but at about thirty-five degrees, he 
would have found that this secondary " ring," very dim in 
general, has one brilliant portion in Cygnu3 ; and this por- 
tion, opposite to that region to which our sun is nearest, is 
situated (in the smaller ring) at the middlf of the sysfim. 

* Holden, Puhlicafions Washburrt Observatori/ , II. 



60 



KNOWLEDGE 



[Mabch 1, 1898. 



Besides, the part of the Milky Way in Cygnus is remark- 
able from more than one point of view. The luminous spot 
p— y Cygui is the ciili/ luminous patch situated in the 
" secondary branch,'' but near the dark space. It is an 
exception to the manner of distribution of brightness over 
the breadth of the Milky Way, between the Eagle and 
Cassiopeia. It is evidently connected with several other 
very brilliant regions (the spots a. — A, p— tt Cygni, etc., i 
perhaps to the series of spots west of Altair). There are - 
in the Milky Way other more luminous spots, but they I 
are much smaller. Sir William Herschel here found his ' 
maximum gauge (5<S8 stars in a telescopic field of 15'-4). 
Not far from here, Kapteyn placed the centre of the 
agglomeration of bright stars in the neighbourhood of the 
sun. ^\ ithout wishing to dogmatize, it is here that I 
would place the central condensation of a galactic spiral ; 
the sun is thus found between this central nucleus and the 
spirals directed towards Monoceros, in a region relatively 
sparse . As to giving a rather more definite form to such 
a spiral, it is a research that I have sometimes attempted, 
Dut it would be premature to give the result here ; more- 
over, many kinds of spirals are in accord with the theory. 

For want of space many considerations could not be 
presented or only glanced at. In concluding, I wish to 
insist that this theory does not pretend to give an explana- 
tion of all the facts that are grouped about a phenomenon 
so complicated as the Milky ^Vay, but that it is to be taken 
above all as a " working hypothesis." 

Errata. — In my article in the .lanuary Number, 1898, 
of Knowledge, p. 12, line 21, read : " Sir John Herschel 
has not stated," etc. ; p. 13, line 15, read : " these points 
have not been raised," etc. 

It would be just to add that the admirable photographs 
of the Milky Way by Pickering have appeared after my 
first article was written. 



^tttttU. 



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

TAKIABLE STARS. 
To the Editors of Knowledge. 

Sias, — Since my note of .July 28th, Knowledge, October, 
1897, I have seventy-five observations of R Scuti, making 
in all one hundred and forty-eight up to the close of the 
season, when the star passed westwards. Each of these 
observations is the mean of two to five views. 

As heretofore stated, neither Chandler or "The Com- 
panion " gave data for this star in 1897, but, following their 
computations of previous years, the computed and observed 
dates of the extreme phases of the star are as follows ; — 







Vlaxima 






Minima. 






C. 


0. 


Mtiu'. 


c. 


0. 

G 


Mag'. 


1896. May 


(i 


„ 




10 


June 


— 


11 


5 1 


11 


29 


6-2 


July 


Irt 


17 


r,-i 


— 


31 


62 


August 


— 


13 


5-S 


21 


— 


— 


September 


25 





— 





21 


8-5 


October 


— 


— 


— 1 


31 


— 


— 


November ) . . 


— 


7 


56 


— 


17 


5-8 


December 


■"' 


— 


— 


— 




— 



From July 31st to September 21st the fall (excepting 
some small fluctuations) was steady, and was followed by 
a rise of similar character until November 0th, when it 
began to fall again, making probably another reversal like 
those of May 6th and September 21st. The latest obser- 
vation of the star was November 17th. 

From 1890, December 29th — the computed date of 
maximum of R Ijeonis that year, as given by " The Com- 
panion — another maximum was due in 1897, November 7th ; 
but the same authority, and Chandler, give the date as 
October Hth, which is apparently a correction of thirty 
days : but the star, on its last rise, appeared so near 
daybreak that observations were inconvenient. It fell in 
with my habits, however, and as soon as it rose above the 
horizon before day, I gave it attention, and submit the 
following data, which covers the means of twenty obser- 
vations, but only the changes are given : — 

Milgr. Mair. 

1897. October 4 67 1897. November 3 7 1 

6 e-4 ., 4 7-2 

,. 12 6 3 „ C, 7-3 

13 6a .. 11 7-4 

17 61 „ 15 7-5 

21 60 .. 23 76 

2J. 6 3 „ 29 80 

26 6-6 December 6 8-3 

.30 6-9 

A maximum on October 20th is indicated, but some 
other observers may be able to show that one occurred 
earlier. It is to be hoped that someone has seen the star 
in September. 

Ceti (Mirai has been at a stand for some days, nearly 
on a level with 60 and 70, or at 5-5 magnitude. 

1 found S S Cygni at a maximum January 17th, at 
8'5 magnitude, unchanged on 22nd, and a step or two 
fainter on 25th. On 26th, the seeing being very poor, the 
star was hardly visible. The period on this appearance 
was forty-three days, the previous one being sixty days, 
and it seems to have remained at maximom longer this 
time than heretofore. 

Cloudiness has been the rule throughout the States at 
nights for some time ; the mornings are more favourable, 
but are hazy and damp ^^^_^^ Flanery. 

Memphis, Tenn., L js.A., 

28th January, 1898. 



* Kapteyn, Verslaijen Koii. Akadcmie i\ WeU iscli. te Amstji-dam 
1892, 1893. 



THE DRAPER CATALOaUE. 
To the Editors of Knowledge. 

Sirs, — Mr. Maunder has made a mistake in his article 
in your February Number in describing the Draper Cata- 
logue as a complete catalogue of the spectra of stars 
down to the eighth magnitude. This is certainly incorrect. 
But one drawback to this catalogue (as well as to many 
other catalogues) is that we do not know the point down 
to which it is complete, and are, consequently, liable to 
err in applying its results to star distribution generally. 
The Draper Catalogue is not complete up to the fifth magni- 
tude. For instance, it does not contain the star 3 Aquarii, 
measured 4-62 in the llanard Phutometri/, and 4-84 at 
Oxford. Between the fifth and sixth magnitudes the 
omissions are pretty numerous ; for example, 36 Aquilse, 
measured 5-23 in both the Oxford and Harvard Catalogues. 
The Harrard Ph^toiiietn/ contains some stars lying farther 
south than any in the Draper Catalogue, but the latter 
does not contain thirty or forty of those measured at 
Oxford as under the sixth magnitude. 50 Pegasi is another 
instance in which the omitted star is brighter than the 
fifth magnitude. I am not writing for the purpose of 



March 1, 1898.] 



KNOWLEDGE. 



61 



discrediting the catalogue, but in the hope that Prof. 
Pickeriug may publish a supplement correcting any errors 
in it that have since been detected, and making it complete 
up to, say, magnitude G-5. According to his present views, 
moreover, the kinds of spectra enumerated would, I believe, 
be less numerous, E and 1 F practically disappearing. In 
his late list of the spectra of bright southern stars in 
the Aatrophi/xical .lournul the varieties of spectra are 
indicated (when not exactly corresponding with a given 
type) by the two types between which they lie, with 
a figure indicating the position between them. Thus 
ASF indicates a spectrum just halfway between A and F 
(the estimate being made in tenths), while A 4 F indicates 
that it is somewhat nearer to A than to F, and A 1 F is 
very nearly equivalent to A. This kind of designation 
will be found more convenient to those who are well 
acquainted with the Draper Catalogue than the more 
elaborate classification of Miss Maury. 

W. H. S. MoNCK. 

SPECTRUM OF o CETI. 

To the Eilitors of Knowledge. 

Sirs, — The reproduction of the spectrum of o Ceti is a 
ninefold enlargement from a negative obtained on Novem- 
ber 29th, on an Edwards isochromatic plate, with a small 
direct compound prism near the focal plane of the fifteen- 
inch objective. l\xtra breadth has been given to the 
enlargement by a cylindrical lens. All the fine lines in the 
picture have been verified by comparison with the negative, 
which shows also many details lost in the enlargement. 
Some of the lines and edges of bands are numbered for 
reference to the following table of wave lengths : — 



which, by the kindness of the Eev. Espin, is in the 
possession of the observatory ; but probably the lines S 
and 7 are much brighter now, while ^ cannot be compared, 
this region not being included in the copy of the Harvard 
photograph. 

There appears to have been a progressive change during 
the last seven weeks in the relative intensities of parts of 
the continuous spectrum. The maximum brightness in 
the accompanying photograph is between the numbers 
three and four. On December 11th the brightest parts 
are the two columns near No. 9, and on December 19th 
this change is stiU more pronounced. 

Wax,ter Sidgreaves, S.J. 

Stonyhurst College Obsel•^'atory, 
8th January, 1898. 



1 4227 


4 4757 


7 5162 


2 4421 


5 4842 


8 5237 


3 4580 


G 4950 


9 5445 
10 5755 


The banded spectrum 


is the same, 


in general, as that of 




X Herculis and stars of this class, the minor differences 
of which are under examination at present. 

The characteristic of the spectrum of o Ceti is its hydro- 
gen radiation. The two brilliant lines Hj and H^ have 
lost nothing during the last seven weeks. The missing 
lines Hf and H^ would both be well marked on the plate 
if their radiations arrived. Of the former there is no trace 
on any of the plates. Of the latter there may be a feeble 
representative : there is a weak division of the absorption 
baud on the red side of No. 5, at the position of H^, 
and this may be a remnant of H^ light unabsorbed by 
the superposed origin of the dark band. 

Smaller photographs of the spectrum, by a half prism 
and short focus camera lens, show the bright hydrogen 
lines y, 5, 4, and'r^, with the dark calcium bands at H and K. 
The hydrogen spectrum is therefore substantially the same 
now as it appears on a copy of a Harvard College photo- 
graph taken some time previous to the spring of 1892, 



ERRATA IX TIMES OF ECL1P8K3 OF THE MOON. 
To the Editors of Knowledge. 

Sirs, — I expected you would have noticed in February 
Number the erroneous times given for the moon's eclipse 
in .January Number, but I do not observe any correction. 

Any great mistake in the XKutical Almanac is so unusual 
that it is not wonderful it should appear in other publi- 
cations ; but as all the eclipses of the moon for this year 
are wrong in the Nuutical Almanar for 1898, it is of impor- 
tance that it should be known. The errata are given in 
Xiiutical Almanac for 1899, and the true values are given 
in W'hitaln'i's Aliiianaclc, the nearest second ; but so many 
almanacks have been more or less caught that you will 
pardon me for sending you a line. Lewis Hensley. 

Hitchin Vicarage, 

February 22nd, 1898. 

' LIQUID FLUORIXE." 

To the Editors of Knowledge. 

Sirs, — In the article on "Fluorine" there is an ex- 
_ ^ „ , , pression made use of which, I 

think, requires some explanation. 
It is — " absolute zero, where, if 
our present knowledge is of any 
worth, the life of the universe itself 
would be extinguished." 

What is the life here meant '? 
Of course a much less minus 
temperature than —210° would ex- 
tinguish all animal life on any 
planet ; the " life of the universe " 
must be something else. 

3, Cator Road, ^- ^- ^«''^=^- 

Sydenham, S.E., 

2nd February, 1898. 

[In writing of a particle of matter, its energy of motion 
— that is to say, its heat — may be considered as the vitality 
of the particle. When we speak of " live steam," for 
mstance, we mean steam at a high temperature and 
pressure. Now, a gas expands by ^^lard of its volume (at 
0' C. and 760 min. bar. pressure) for every degree 
Centigrade through which the temperature is raised, and if 
the temperature be lowered by one degree it contracts by 
that amount ; so that " absolute zero " is the point where 
the gas has contracted theoretically to nothing, namely, 
— 273° C. At this point a gas has no volume and no 
pressure, and may be considered as dead. This is what I 
meant when I said that at absolute zero the life of the 
universe itself would be extinguished. — C. F. Townsend.] 



-i^L J 



62 



KNOWLEDGE 



[March 1, 1898. 



THE MASSES AND DISTANCES OF BINARY 
STARS. 

By J. E. Gore, f.r.a.s. 

IN a valuable and interesting volume recently published 
by Doctor See, of the Lowell Observatory, Mexico, 
he gives a recomputation of the orbits of forty ol 
the best known binary systems. Some of his results 
— all of which are based on a careful consideration 
of the best recorded measures — do not differ widely from 
those of other computors. In other cases, however, his 
orbits diiler considerably from those previously published ; 
and as he has included very recent measures in his dis- 
cussions, his results are probably more accurate than any 
hitherto published. In the following table I give the period 
(P) and the semi-axis major (a) of the orbits found by 
Dr. See. From these I have computed the hypothetical 
parallax, /i= "i, or the parallax of the star on the assump- 
tion that the mass of the system is equal to the sun's mass. 
To these I have added the magnitudes of the stars which 
have been photometrically determined at Harvard, and the 
character of the star's spectrum, 1. being the Sirian and 
II. the solar type. 



star. 


Period. 
Tears. 


Semi- 
Aiis , 
Major. 


Hypo- 
thetical 
Parallax. 


Mag. 


Spec- 
triun. 


Remarks. 






Sees. 


~Secs.~' 








StTOTe3062... 


104-61 


1.3712 


0-061 




II. 




■1) CassiopeitD 


195-76 


8-2128 


0-243 


3-64 


II. 




V Aiidromedffi 


54-0 


0-3705 


0026 


(5) 


... 


Magnitude esti- 
mated. 


Sirius 


52-20 


8-0316 


0-575 


-H-43 


I. 




» Ai-gfls 


22-00 


0-6548 


0-083 


5-49 






^ Cancri 


60-0 


0-8579 


0-056 


4-72 


II. 




StrnveSm... 


34-00 


0-6692 


0-06;J 




II. 




w Leonis 


116-20 


0-88241 


0037 


5-55 


II. 




A Urate Maj. 
i tJrsse Mai. 


97-0 


0-3440 


0-016 


1-43 


I. 




60-00 


2-508 


0-163 


3-80 


11. 




£ 2M 


77-0 


0-3467 


0-019 




11. 




S 235 


80-0 


0-8690 


0-047 


5-56 


II. 




y Centauri ... 


88-0 


1-0232 


0-051 


2-36 


I. 




y Virginia ... 


194-0 


3-989 


0119 


2-84 


II. 




•42 Coma; .. 


25-556 


0-6416 


0-074 


4-38 


II. 




2 269 


48-8 


0-3248 


0024 








25 Can. Venat. 


184-0 


1-1307 


0-035 


5-00 


l. 




a Centauri ... 


81-10 


17-70 


0-944 


0-20 


II. 




2 285 


76-67 


0-3975 


0022 








( BoiitJa .. 


1-28-0 


5-5578 


0-218 


4-60 


li! 




7j Cor. Bor. ... 


41-60 


0-9165 


0076 


4-98 


11. 




^' Boritis ... 


219-42 


12679 


0-034 


(6-5) 


I. 


Magnitude esti- 
mated. 


2 298 


52-0 


0-7989 


0-057 




II. 




V Cor. Bor. ... 


73 


0-7357 


0-042 


4-18 


I. 




^ Scorpii 


104-0 


1-3612 


0-061 


4-10 


II. 




a- Cor. Bor.... 


3700 


3-8187 


0-074 


5-:!9 


II. 




f Herculis ... 


35-00 


1-4321 


0-134 


309 


II. 




p 416 


33-0 


1-2212 


0-118 


5-85 






2 217:! 


46-0 


1-14-28 


0-089 




li. 




n' Herculis... 


45-0 


1-390 


0-110 


(9-4) 




Estimated Magni- 
tude. 


T Ophiuchi ... 


230-0 


1-2495 


0-033 


4-93 


II. 


70 Ophiuchi .. 


88-3954 


4-548 


0-229 


4-11 


11. 


Computed mass of 
system equals 
6-368 times suns 


99 Herculis... 


54-5 


1-014 


0-070 


5-30 


II. 


Mass of system 
equals sun's 
mass. 


S Sagittarii... 


18-85 


0-686 


0-097 


2-K) 


1. 


Star 1-75 magni- 
tude brighter 
than sun. 


V Cor. Aust, 


152-7 


2-450 


0-085 


4-28 


II. 




/3 Delphini ... 


27-66 


0-6724 


0073 


3-74 


1. 




4 Aquarii ... 


1-290 


0-732 


0028 




II. 




& Equulii 


11-45 


0-452 


0089 


4-'60 


II. 




K Pegasi 


11-42 


0-4'216 


0083 


4-21 


II. 




.'W Pegasi ... 


24-0 


0-8904 


0-107 


5-83 


u. 




;3 883 


5-5 


0-621 


01993 


(7-8) 




Estimated magni- 
tude. 



Now, if we take the sun's stellar magnitude as —27: 
that is, twenty-seven magnitudes below the zero magnitude 
(see my paper in KNo-nxEixiE for June, 1895) : and compute 
what its magnitude would be if removed to the distance 
indicated by the " hypothetical parallax," we find that in 
most cases the binary star is brighter than the sun would 



be if placed at this distance. It follows that to make the 
sun of equal brightness with the star it should be placed 
at a less distance than that indicated by the " hypothetical 
parallax " — that is, tho parallax of the binary star should 
be increased. This would have the effect of diminishing 
the mass of the system, as I showed in a former paper. 
(Knowledge, December, 1894.) Now if B represents the 
number of times which the star exceeds the sun in bright- 
ness when both are placed at the distance indicated by 
the "hypothetical parallax," and s represents the increased 
parallax, we have .s =;)^^B = -"^ f Again, if w and »», 

represent the masses of the components of the binary 
system, and //' + /», -«M, where M is the mass of 
the sun, we have, taking M=:l, )(=^„ and for the 
parallax, s, ?i ^^jt;., or, substituting the value of i found 
above, and reducing, we have ?^ ^= ~. To find B we have 
(sun's mag. — star's mag.) xO'4 log. B. 

Let us now consider some of the most remarkable cases 
in the above list which have spectra of the solar type. 
I omit those in which the difference of magnitude between 
the sun and star does not exceed one and a half magnitude, 
or about four times. 

t liootis. In this case the sun would be reduced to a 
star of 2 88 magnitude, which gives a difference of 1'72 
magnitude in favour of the sim. This would make the 
sun 4-H7.J times brighter than the star at equal distances. 
The parallax must therefore be diminished, and hence the 
mass of the system would be B|=10-77 times the mass of 
the sun. 

Scorpii. Here the sun would be reduced to magnitude 
.5-64, giving a difference of 1'54 magnitude in favour 
of the star. Hence the mass of the .system would be 
^. I.i5 of the sun's mass. The spectrum is a doubtful one 
of the second type (F '?). 

T Ophiuchi. In this case the sun would be reduced to 
magnitude 6-98, if placed at the distance indicated by the 
" hypothetical parallax," and, the star's photometrical 
magnitude being 4-93, there is a difference of 2 OH 
magnitudes in favour of the star. Hence B = 6-607, and 
n = iV> °^ '■^^ mass of the system would be one-seventeenth 
of the sun's mass, and the star's parallax about 0-085". 
The spectrum is of the solar type. 

In the case of 99 Herculis the sun would be reduced to 
magnitude ."cSI, or almost exactly equal to the star in 
brightness, and, the spectrum being of the solar type, the 
mass of the system is probably equal to the mass of the 
sun. The companion is very faint and of a purple colour, 
and may possibly be approaching the planetary stage of 
its history. 

a Centauri is a very interesting case. Here the sun 
would be reduced to a star of magnitude -0-31, or 0-31 
magnitude brighter than a star of zero magnitude ; and as 
the star's photometric magnitude is 0-20, we have a 
difference of 0'.51 magnitude in favour of the sun, or 
B = ]-:^;. Hence the parallax would be reduced to J 
=0-746", and the mass of the system would be 2-023 
times the sun's mass. As Dr. GiU found a parallax of 
0-75", and Dr. See computes from his orbit a mass of 2 00, 
the mass of the sun, it would seem that the orbit, parallax, 
and photometric magnitude of this remarkable star have 
been correctly determined. 

With reference to the binary stars having the Sirian 
type of spectrum, let us consider the case of Sirius itself. 
If the spectrum of Sirius were of the solar type and strictly 
comparable with the sun, I find that its parallax would be 
about 1-58", and its mass about one twenty-first part of 



Makch 1, 1898.] 



KNOWLEDGE, 



63 



the sun's mass. But Dr. Gill found a parallax of 0'38", 
and ])r. See computes from bis own orbit and this 
parallax that the mass of the system is 3'473 times the 
mass of the sun. ■ Now I lind that if the sun were placed 
at the distance indicated by Dr. Ci ill's parallax it would be 
reduced to a star of I'tiT magnitude, or 3-10 magnitudes 
fainter than Sirius. This implies that Sirius is 17'38 
times brighter than the sim would be at the same distance. 
But if Sirius were of the same density and intrinsic 
brightness as the sun, its mass would imply that it should 
be only 1-773 (2-3G)' ■ brighter than the sun. Hence 
we see that Sirius is nearly ten times brighter than 
it would be had it the same density and brightness of 
surface as the sun has. Hence, as Dr. See says, "there 
is some reason to suppose that sirius is very much 
expanded, more nearly resembling a nebula than the sun." 
i{> Ursse Majoris is a very brilliant star. Here we have 
the sun reduced to a star of 8'55 magnitude, or a 
difference of i-V2 magnitudes in favour of the star. Hence 
B=-14-47 and h = .,.\j. The spectrum is of the Sirian 
type. For y Cor.'JBor., I find B = 8-091 and n = ..\^. 
y Centauri is another brilliant star. Here B = 29-38 and 

There are two remarkable cases in which the sun, if 
placed at the distance indicated by the " hypothetical 
parallax," would be considerably hriijhtir than the binary 
star. One of these, |x' Herculis, is referred to in a former 
paper (Knowledge, December, 1894). Here, the sun 
would be reduced to 1-36 magnitude, and, taking the star's 
magnitude as 9-4, we have a difference of about five 
magnitudes in favour of the mn. This would nduce the 
star's parallax to 0011', and would make its mass no less 
than one thousand times the mass of the sun ! The star 
being so faint its spectrum has not been determined, but 
it forms a distant companion to ix.- Herculis, the magnitude 
of which was measured 3-49 at Harvard, or nearly one 
magnitude brighter than the sun would be if placed at the 
" hypothetical " distance. If we increase its distance ten 
times, as indicated by the above calculation, we must 
conclude that ju.- Herculis is no less than two hundred 
and twenty-three times the brightness of the sun ! 
According to the Draper Catalogue the brighter star has a 
doubtful spectrum of the solar type (Class II. :'). As both 
stars have a common proper motion, they probably lie at 
practically the same distance from the earth, and the only 
explanation of the above startling results seems to be that 
the binary star has — like the companion to Sirius — cooled 
down, and is, therefore, not comparable in its physical 
constitution with the sim. 

Another remarkable case is that of p 883— a binary of 
very short period, whose rapidity of motion has recently 
been discovered by Dr. See. Here the difl'erence of bright- 
ness is about four magnitudes in favour of the sun, which 
would make the mass of the system about two hundred 
and fifty-one times the sun's mass ! But here again we do 
not know the character of its spectrum, so cannot say 
whether the star is really comparable with the sun in 
brightness. 

.^ 

^YE understand that Mr. Thomas H. Blakesley, m.a., c.e., 
the weU-knowD instructor in physics and mathematics at 
the Royal ^aval College, Greenwich, has resigned his seat 
at the Coimcil Board of the Physical Society of London. 
Mr. Blakesley is, therefore, no longer Honorary Secretary 
of that learned body. 

* The mass of the bright star is 2 36 times the mass of the 
sun. The mass of the companion, which is very faint (and does not 
aifect the brightness of the primary), is, according to Dr. See, 1-113 
times the sun's mass. 



H.R.H. the Prince of Wales has graciously consented 
to open the International Photographic Exhibition at 
the Crystal Palace. Intending exhibitors are asked to 
note that the date of opening of the Exhibition by His 
Royal Highness has been fixed by him for Monday, 
April 25th, and not Wednesday, April 27th, as originally 
announced. The latest date for the reception of exhibits 
in each section will therefore be two days earlier than 
that first stated on the prospectus. 



The number of applications for patents during the year 
1897 was thirty thousand nine hundred and thirty-six, as 
compared with thirty thousand one hundred and ninety-four 
in 1896 and twenty-five thousand and sixty-five in 1895. 
Although the number of patents applied for illustrates the 
progress of inventive activity, it does not atfjrd any reliable 
criterion as to the number which arrive at maturity. Out 
of the thirty thousand one hundred and ninety-four in 
1896, for example, only thirteen thousand three hundred 
and sixty were completed, the rest being allowed to lapse 
after the nine months' protection. Not a few of the 
applicants for patents are women, of whom there were 
about seven hundred in 1896 ; some hundred and fifty of 
these inventions relating to dress. 



A new bibliography of great value to scientists is now 
being prepared of ah the technical works in that unique 
and most easily accessible collection, the Patent Oflice 
Library, and will be completed in two volumes. In the 
first volume the books and pamphlets, etc., will be indexed 
under the names of authors, and the second volume wiU 
be a subject-matter index. A proof, including the letters 
.\, B, C, D, consisting of two hundred and forty pages of 
the first volume, has been placed in the Library for the use 
of the public. 

Notitfs of Boolts. 



Tlw New Psychology. By Dr. E. W. Scripture. Illus- 
trated. (Walter Scott.) 63. By such a book as this, 
belonging to the Contemporary Science Series, psychology is 
lifted out of the arena of abstract philosophy and established 
upon the sound basis of experimental science. The develop- 
ment of the new or experimental psychology within the 
last few years has produced a large amount of remarkable 
material which has remained almost unknown except to 
speciahsts. Most of this work has been done in Germany 
and the United States, and Dr. Scripture is one of the 
foremost of the workers. What a vast amount of material 
has been accumulated may be seen by reference to the 
" Psychological Index," or those two excellent journals the 
Psychdoijicid Review and the Journal of Psychology — the 
like of which do not exist in this covmtry. Perhaps, now 
that a psychological department has been established 
at University College, we may also be able to give similar 
hostages to fortune. The fact is that many men of science 
in this country are disinclined to give psychology a locus 
standi : the chemist and physicist look upon it as akin to 
metaphysics, and the physiologist regards it as a pre- 
sumptuous sub-department of his branch of natural 
knowledge. It is not clear why physiologists generally do 
not look with eyes of favour upon this younger science, for 
surely it is immaterial what designation is given to any 
department of scientific work so long as facts are being 
accumulated. Moreover, the barriers between the various 
sciences are being broken down daily. The methods and 



64 



KNOWLEDGE. 



[Mabch 1, 1898. 



results of physical science (using the term in its widest 
sense) are being used to assist the progress of the natural 
sciences ; and the new psj'chology is a valuable product of 
this combination. 

Dr. Scripture's volume contains a clear statement of the 
chief work that has been done on what may be termed the 
connection between thought and action. It is not con- 
cerned with the academic distinctions between sensation and 
perception, and similar discussions of ideas, but treats of 
mental life in relation to time, energy, and space, and shows 
how physical Lnstruments may be used to measure these 
relationships. The book is in itself a justification of the 
claims of psychology to a place among experimental 
sciences. 

Natural Causes and Supernatural Secminffs. By Henry 
Maudsley, m.d. Third Edition. (Kegan Paul.) Dr. 
Maudsley's book is neatly, if not completely, epitomized 
in its title. Presentiments, imprecations, magic incanta- 
tions, predictions of witchcraft, omens, hallucinations, 
and all phenomena usually ascribed to the supernatural, 
are here sternly confronted with the unsympathetic con- 
clusions drawn by cool reason from cause and effect. The 
multitude will always take its opinions from custom and 
tradition, and on the authority of others ; but there are 
not a few who agree with Voltaire when he said that 
" magic words are capable of destroying a whole flock 
of sheep — if the incantation be accompanied with a 
sufiicient dose of arsenic." The author looks upon life 
as an intensely real thing, and apparently regards the 
whole of our existence as a sort of complex mosaic, the 
intrinsic beauty of which is masked by the creations 
of unbridled imagination. It is plausible but quite false 
presumption that mankind in general act on rational 
principles : the masses, being mainly foolish, have always 
held to the wrong opinion until dragged out of it by the 
labours of the few who differed ; and there is probably 
much truth in Dr. Maudsley's assertion that " the 
extinction of a few hundred persons in a generation, who 
keep the torch of knowledge burning in Christendom, 
would bring progress to a standstill, and might throw the 
world back into intellectual barbarism in the com-se of two 
or three generations ; all the more easily because, besides 
the passive resistance of a dead weight of ignorance, there 
is a vast and powerful organization of hostile superstition 
watching and working to stop intellectual progress." In 
short, the volume affords us a glimpse into the mighty 
edifice of error built on the basis of defective observation ; 
and, abandoning the preposterous plane of speculative 
intuitions, we have presented before us images in the 
unassuming habiliments of sense and reason. Still, as the 
senses are only so many narrow chinks of experience 
between two unknown infinities — the infinitely great and 
the infinitely small— there is a danger of oscillatLng from 
the warm equatorial regions of imagination to the extreme 
polar climes of frigid logical deduction. 

By Roatlsidc and River. By H. Mead Briggs. (Elliot 
Stock.) 3s. 6d. Richard Jefferies has had of late many 
imitators. For some years past the public has been 
liberally supplied with a class of book of which " By Road- 
side and River " is an example. The authors, without 
laying claim to scientific accuracy, display, as a rule, some 
powers of observation, and Mr. Mead Briggs is no exception. 
The one thing necessary to make such a book readable, 
however, is a fair command of literary English, and the 
power of recording the author's observations and meditations 
(if we must have these meditations) in language which is 
intelligible. But it is in those very points that Mr. Mead 
Briggs comes lamentably to grief. It is scarcely an 
exaggeration to say that in every page of " By Roadside 



and River " the reader is irritated and perplexed by some 
atrocious solecism, some wanton dislocation of a trite 
expression, even if he escape the puerile essays in metre 
with which the book is plentifully studded. Passing by 
with a shudder such combinations as "child and bland- 
like " (applied to a bird which "ventures to speak in a 
shrilly voice "), we are pulled up short by the following 
reflection : " But accident and misfortune appearing 
suddenly upon our best bright days, comes [s/c] as a thief 
in the night to take our happiness, and leaves our senses 
numbed." The swallow is depicted as " reflecting her 
dainty form in the mirrored stream. " 'When Jlr. Briggs 
descends from reminiscence and moralization to a record 
of facts, he has much that is interesting, if little that is 
new, to tell us. His observations of nature are, in the 
main, just, though we believe naturalists are agreed that 
the cuckoo's method of depositing her egg in the nests of 
other birds is by the beak, and not by thtf claw ; and also 
that the eyes of the mole are practically useless, and that 
this creature cannot " see with ease in the dark caverns 
of the earth. " 

WiM Traits in Tame Animals, being some Familiar Studies 
in Erolution. By Louis Robinson, m.d. (Blackwood.) 
Illustrated. 10s. (id. net. This is a very readable book 
for several reasons. It is well written ; it deals with 
simple everyday matters. The theories and suggestions it 
contains are plausible, and, above all, it teaches the reader 
to think. The plan of the book is to discuss familiar traits 
in tame animals such as dogs, horses, cats, etc., to compare 
these traits with those of wild animals, and to seek to trace 
their origin and explain their significance. The author 
succeeds fairly well, but, as would be expected, he occasion- 
ally pushes an analogy or a theory too far, and there is a 
paucity of facts throughout. Some of the suggestions and 
hints for study and research are valuable. If there is not 
much that is actually new in the book, there are many 
things which are put in a new and generally attractive 
light. Altogether, it is a book which should be read by 
every naturalist, and parts of it could, with profit, be read 
more than once. It will prove very valuable to the young 
student, providing he reads it slowly, and, thinking for 
himself, sifts the evidence, takes nothing for granted, and, 
above all, compares it with the greatest book of all — the 
book of nature. 

Montai^/ne mid Shiih2jere. By John M. Robertson. 
(The University Press, Limited.) 5s. net. The debt of 
genius to its forbears must always be considerable, for 
human experience is so " cabin'd, cribb'd, confin'd," 
that even Shakspere could only write upon what he had 
himself observed, heard, or read. That he was familiar 
with Florio's rendering of Montaigne has long been un- 
questioned, but the precise degree in which he was 
influenced by the great essayist will always form material 
for interesting if not altogether profitable inquiry. In 
this handsomely printed and elegantly mounted volume, 
Mr. John M. Robertson has brought his critical acumen 
to bear upon the problem, which he discusses throughout 
with a refreshing freedom from that venomous antipathy 
which so often disfigures these analytical examinations of 
the work of the immortals. " We are embarked, " he says, 
" not on a quest for plagiarisms, but on a study of the 
growth of a wonderful mind. And in the idea that much 
of the growth is traceable to the fertilizing contact of a 
foreign intelligence, there can be nothing but interest and 
attraction for those who have mastered the primary 
sociological truth that such contacts of cultures are the 
very life of civilization." 

In this eminently fair introduction to the study of the 
comparisons will hs found the key to ^Ir. Robertson's 



Iaboh 1, 1898.] 



KNOWLEDGE. 



65 



work ; and if he has claimed more for his thesis than the 
occasional identity of thought and similarity of expression 
will fairly carry, still he has not for an instant wavered in 
his allegiance to the study on which he set out. But he 
appears to contradict himself upon the important question 
as to whether Shakspere had seen parts of Fiorio's 
translation earlier than 160;{ — the year of its publication — 
" or even that he might have read Montaigne in the 
original" (page 12); for later on in the essay (page 50) 
Mr. Robertson says : " That Shakspere read Montaigne in 
the original once seemed probable to me, as to others ; but 
on closer study I consider it unlikely, were it only because 
the Montaigne influence begins in Hamlet." In that case, 
of course, at least one of Mr. Eabertson's parallelisms 
falls to the ground. 

That Montaigne lighted a lamp in Shakspere which 
shone through all his after work is clear, but the quaint 
old French philosopher's searching criticisms of life were 
given an immortal setting by the poetic genius of the 
English dramatist. " The influence," says Mr. Robertson, 
" is from the very start of that high sort in which he that 
takes becomes co-thinker with him that gives, Shakspere's 
absorption of Montaigne being as vital as Montaigne's own 
assimilation of the thoughts of his classics. The process 
is one not of surface reflection, but of kindling by contact ; 
and we seem to see even the vibration of the style passing 
from one intelligence to the other, the nervous and copious 
speech of Montaigne awakening Shakspere to a new sense 
of power over rhythm and poignant phrase, at the same 
time that the stimulus of the thought gives him a new 
confidence in the validity of his own reflections." 

The subject is a fascinating one indeed, and not alone 
to the student of Shakspere, for Mr. Robertson's critical 
method is so unemotional and impassive, and yet so 
scrupulously just and many sided, as to afl:ord in itself an 
interesting and instructive study, quite apart from the 
special interest of its subject. 

The Elfinentx of Astionoimj. By Chas. A. Young, Ph.D. 
(Ginn & Co.) Illustrated. This edition of Prof. Young's 
book has been revised and brought up to date. The 
author is well known by his larger work — " General 
Astronomy " ; but it is asserted that the volume under 
notice is not a mere compilation from the more pretentious 
work. Its purpose is to teach astronomical science to 
scholars in middle-class schools, and more especially those 
who have not much mathematical knowledge beyond the 
limits of simple algebraic and trigonometrical fmictions. 
Indeed, the science of astronomy may be made interesting 
without any knowledge at all of formula. The book, we 
think, fiUs the requirements of the class of students 
specified. All the latest researches are mentioned, includ- 
ing the eclipse of the sun in August, 1896, and genuine 
additions to oxvc knowledge are incorporated. Clear de- 
scriptions are given of the planets, stars, nebuls, etc. — and 
by clear, we mean that the author here exhibits the happy 
knack of conveying information, even on intricate sub- 
jects, in language shorn of all pedantry : an acquisition, or 
a gift — it is diflicult to say which — not by any means 
common among scientific men of the first rank. A little 
pamphlet, called a uranography, is tacked on, which was 
at first intended to be issued separately ; it is meant as an 
open-air guide to a study of the principal stars, and 
is accompanied by charts representing the chief constella- 
tions. A good feature of the whole book consists in the 
free distribution of a large number of first-rate diagrams, 
which add not a little to the general attractiveness of the 
volume — a great desideratum in text-books. A synopsis 
and questions are added for the benefit of those who read 
the book for examination purposes. 



SHORT NOTICES. 

The Machinery of the Univerae. " Romance of Science " Series. 
By A. E. Dolbcar. (Society for Promoting Christian Knowledge.) 
Illustrated. An ambitious title, truly ! and also misleading. " The 
machinery of the universe " turns out to bo that mysterious ether 
which, if occasion rei(uires, can perform either the functions of a 
Uuid or a solid, or do duty for both at one and the same time. 
Writing of the number of molecules in the visible universe, the 
author says (page 29) : " The point is that there is a definite, computable 
number." A definite number there may be, but computiihle, never. 
As well might one say that all the thoughts which have ever entered 
the myria<ls of human heads are computable. Although the author 
displays much eruditio'n, he has not yet learnt to take off his shoes, 
and to cover himself with sackcloth and ashes, when entering the 
inner court of the great unknown. 

Chemisfri/ for Photographers. By C. F. Townsend. (Dawbarn 
<fe Ward.) Illustrated. Is. net. There is much in this baok of use 
to the practical amateur photographer who wishes to understand the 
nature of the various thomicals he has to use. There arc brief but 
ample explanations of such mysteries as the salts of silver and 
development; also useful chapters on the different printing processes, 
impurities in acids and alkalis, and a number of hints on miscellaneous 
subjects connected with the art of photography. 

Pictorial Instruction Object Lesaoiis. By Or. Colomb. Adapted 
into English by Seymour J. Gubb, u A. (Rclfe Bros.) Illustrated. 
Is. (id. Akin to that popular French scientilic book of Paul Bert's,- 
the idea of M. Colomb is to combine in his book pictorial illustration 
with instruction in a manner siutablc to be put into the hands of the 
younger generation. It is, in fact, a kind of child's picture book, but 
of a more edifying sort : pictures of everyday life, including manu- 
faotures, domestic operations, natural history, chemistry, physics, 
mineralogy, and so on. A short — very short — description is placed 
underneath each figure. On the whole the book has a very lively 
appearance about it and deserves to be widely known. 

Revolving Planisphere. (George Philip&Son.) 2s. An oval opening 
in the disc of this apparatus represents the horizon for which the 
planisphere is constructod, and the part of the heavens visible at any 
stated time may be found by adjusting the movable disc till the day 
of the month marked upon its edge corresponds with the time of day 
or night figured upon a superposed disc. An auxiliary disc, adjust- 
able once a week, serves the jjurpose of a perpetual calendar. The 
apparatus is ingenious in construction and extremely attractive in 
appearance. 

We have received from Mr. L. CascUa a catalogue of automatic 
recording instruments of various types, described as well as figured, 
among which is a pyrometer, recording results up to -ioOO" F., 
the automatic rain gauge, bai'Ograph, thermograph, electrograph, 
anemograph, and many others; also the actinometcr for measuring 
the heat and light of the sun. A new photo-theodolite here figured 
is of considerable value for detennining the dimensions of olijects 
accurately by means of photographs whicli give true perspective 
pictures, and obviate the use of a large number of note-books in 
surveying operations. 

BOOKS RECEIVED. 

Aiidree and his Salloon. B}' Hem-i Lachambre and Alexis 
Machuron. (Constable.) Illustrated. 63. 

Glass Blowing and Glass Working . By Thomas Bolas. (Dawbarn 
& Ward.) Illustrated. 23. net. 

On Laboratory Arts. By Richard Threlfall, M.A. (Macmillan.) 
Illustrated. 6s. 

The Arrangement of Atoms in Space. By J. H. Tan't Hoff. 
Translated by Arnold Eiloart. (Longmans.) 6s. 6d. 

The Moon. By Richard A. Proctor. Fourth Edition. (Long- 
mans.) Illustrated. 3s. 6d. 

T/ie Tfar of the Worlds. By H. G. Wells. (Heinemann.) 6s. 

Elementary Physics. By John G. Kerr, sr.A. (Blackie.) 
Illustrated. Is. 6d. 

The Story of the British Coinage. By Gertrude B. Rawlings. 
(Newnes.) Illustrated. Is. 

Calendar, History, and General Summary of Eegulations, Science 
and Art Department. (Eyre & Spottiswoode.) Is. 7d. 

The Science of the Ideal. By F. J. Linford- Wilson. (Reeves.) 
Illustrated. 2s. 6d. 

Storm and Sunshine in the Dales. By P. H. Lockwood. (EUiot 
Stock.) Illustrated. 

Bemarkable Comets. Ev W. T. Lynn. Sixth Edition. (Stan- 
ford.) 6d. 

Elementary Botany. By Percy Groom, M A. (Bell.) Illustrated. 
3s. 6d. 

Charles Dickens. By George Gissing. (Blackie.) 23. 6d. 

Terje Viken. From the Xorse of Henrik Ibsen. By Alfred 
Lishuian. (The Author : Fockerby, Goole.) 



66 



KNOWLEDGE 



[Maboh 1, 1898. 



BKiTISH 



a>i^Kf 




ORNITHOLOGICA 



NOTES 



Conducted by Habby F. Witherby, f.z.s., m.b.o.u. 

MisTLE Thrush swallowing Droppings of Young. — 
Last spring I was much interested in watching a pair of 
Mistle Thrushes which had their nest on a branch of a tree 
some twenty feet from the house. From an upper window 
one could get an uninterrupted view down into the nest. 
When the young were hatched I watched the nest very 
carefully, and with a pair of field glasses, which revealed 
every detail of the birds and the nest, I made the 
following observations. As soon as one of the parent 
birds appeared in the tree the four young ones stretched 
up their necks and opened their gaping yellow mouths. 
The old bird cautiously made its way to the edge of the 
nest, and put a piece of a worm first into one mouth, then 
into another (generally only two at a feeding), seeming by 
its actions to discriminate which young ones to feed. 
Immediately it had emptied its mouth the parent put its 
head down to the nest, and one of the young turned round 
and voided its white droppings into the open beak of the 
parent bird, which then swallowed the droppings and flew 
away. In two minutes the other parent appeared, and 
went through exactly the same process. For a fortnight 
I watched this extraordinary method of sanitation many 
times a day. On no occasion did either parent leave the 
nest after feeding the young without swallowing the 
droppings of one young bird and only one. Moreover, on 
several occasions the old bird, after having waited a few 
seconds without result, gave a gentle peck to one of the 
young, which immediately turned round and voided its 
droppings into the parent's mouth. At about every fourth 
visit to the nest one of the parents covered the young for 
a quarter of an hour after having fed them and swallowed 
the droppings, and on several occasions I kept my eyes 
upon the parent during the whole time, but never saw it 
attempt to disgorge. During the last week in which the 
young ones were in the nest the droppings were, apparently, 
sometimes too large to swallow, and consequently they 
were often carried away in the beak ; but every now and 
then they were swallowed. 

I have set these facts out in detail because, although 
it is well known that birds carry away the droppings of the 
young, the fact that they are usually swallowed by certain 
birds seems to have been overlooked. In the second 
volume of Macgillivi-ay's " British Birds," that excellent 
naturalist, the late J. Jenner Weir, in communications to 
the author concerning the habits of the Blackbird, Song 
Thrush, and Mistle Thrush (the nests of which he had 
watched most carefully), mentions the fact that in each 
of these species he observed that the old birds " swallowed 
nearly all the droppings of their brood " during the day ; 
moreover, he shot one of the birds and found the 
droppings in its stomach. In the fourth edition of 



Yarrell's " British Birds " we are merely told that Song 
Thrushes "have been observed to swallow the ficces of their 
offspring." 

In no other book can I find the fact mentioned. It 
^eems to me that either the habit has been overlooked or 
else it requires confirmation, and I have therefore ventured 
to publish this note. 

It is evident that the droppings go into the stomach, 
ind it is also evident that they are sometimes retained for 
at least a quarter of an hour. It is questionable if the 
l)ird would be able to disgorge them after they had 
been in the stomach for fifteen minutes. It is con- 
ceivable that the droppings are taken by the parent bird 
as food, for it would be able to digest what the young 
bird had, perhaps, been unable to assimilate, and would 
thus save a great deal of time in procuring nourishment 
for itself. 

It seems to me that for those well situated for observing 
birds it would be most profitable to ascertain during the 
coming spring what species do swallow the droppings 
of the young, if they do this regularly, and if there is 
sufficient nutriment in them to induce the birds to swallow 
them for the sake of nourishment. If the droppings are 
swallowed for this purpose it may be that they are only 
swallowed when food is scarce. I shall be very glad of 
any further information on this interesting subject. — H-vbry 
F. Witherby. 

Quail in Sussex. — We have had brought us to-day for 
preservation a Quail (C. communis), caught in the lark 
nets near here yesterday. We suppose that the mildness 
of the winter is the cause of its remaininf,' in this country. 
— Edwin A. Pratt, Brighton, January "iSth, 1898. 

Curious Jackdaws Nest. — Last season but one, while 
looking over the grounds at Bretton Hall, near Barnsley, 
I saw sticks protruding from the top of the old chimney 
formerly belonging to the greenhouses. I suspected it to 
be a nest. On making inquiries from the gardener he 
told me it was the nest of a pair of Jackdaws, which had 
filled the chimney with sticks and made their nest on the 
top. On looking in at a doorway at the bottom of the 
chimney I saw it was quite filled from the base, and the 
man told me he had cleared it out several times, but they 
always filled it again. — S. L. Mosley, Educational Museum, 
Huddersfield. 

Early Nesting of the Starling, the Long-tailed Tit, 
AND the House Sparrow.— The Kev. Francis C. E. 
Jourdain writes from Asburne, Derbyshire, that a Starling's 
nest, with nearly fledged young, was found at Bradley at 
the end of January. Mr. W. Dunn, of Exmouth, writes 
that on February 7th he watched a pair of Long-tailed Tits 
collecting moss, evidently for a nest. A brood of House 
Sparrows is also reported from Blackheath, Kent, as having 
been hatched on February loth. 

Cranr- in CouhIi/ Ti/ipefciry (Irish Xafuralisf, February, 1898, 
p. 51), ^A specimen of Qnis communis is reported bv Jlr. W. 
Johnston, of Thurles, to have been shot at Seskin in September, 1896. 

Li/tle Sittern in Cotinti) Cork (Irish Ifuliiralvif, February, 1898, 
p. 51). — Mr. .Tohu .T. Wolfe records that a bird of this species was 
shot on November 8th, 1897, by Mr. W. Sweetman. of Schul), and 
sent to him. 

Liftle Bustard in Norfolk (The Field, February 19th, 1898, 
p. 285). — Licut.-Col. E. A. Butler records that a specimen of the 
Little Bustard (Otis tefrax) was shot on January 25th by Mr. Godwin 
at Fcltwell, ue:ir Dowuliam Market, Norfolk. 

All contributions to the column, either in tlie way of notes 
or photoi/raphs, should be forwarded to Habry F. Witherby, 
at 1, Eliot Place, Blacklieath, Kent. 

Note. — The first issue of Knowikdgk containing British Ornitho- 
logical Notes was that for October, 1897. 



March 1, 1898.] 



KNOWLEDGE 



67 



Wb regret to record the death of Prof. T. Jeffrey Parker, 
F.R.S., whose decease occurred on the 7th November last. 
He was the eldest son of the well-known osteologist, 
William Kitchen Parker, and was born in London in the 
year 1850. Obtaining the associateship of the Royal 
School of Mines in 1871, he, after a short appointment as 
science master in Yorkshire, returned to London and 
became demonstrator under Prof. Huxley, at the latter's 
invitation, at the Royal School of Mines. In 1880 he left 
England for New Zealand, to take up the duties of 
Professor of Biology in the University of Otago, which 
post he retained till his death. Prof. Parker was the 
author of a great number of original scientific memoirs, 
some of which are of far-reaching importance. He also 
wrote some valuable text-books on natural science, one 
of which, to wit, "Lessons in Elementary Biology," has 
been translated into German. In conjunction with Prof. 
Haswell, of Sydney University, he attempted the laborious 
task of writing a large text-book of zoology, which he was 
not destined to see in circulation. Prof. Parker was 
entrusted with the task of forming a museum of biology at 
the Royal School of Mines, on the type system. He 
advocated the study of the lower organisms first in pre- 
ference to the vertebrates, as inculcated by Huxley, and in 
due course secured a triumph over his great teacher on 
this point. As a worker, Prof. Parker was of the first 
rank, and also a luminous teacher. He was a kind, 
considerate, and lovable man, and the biological world is 
the poorer by his untimely death. 



THE KARKINOKOSM, OR WORLD OF 
CRUSTACEA.-II. 

By the Rev. Thomas R. R. Stebbing, ji.a., f.r.s., f.l.s. 

IN the previous chapter examples were given to show 
the extreme divergence of form and structure to be 
found in the Crustacea at large. The difl'erences 
are scarcely less striking that may be seen within 
the limits of the Malacostraca. Yet that group, by 
the close interweaving of affinities, is as inseparably com- 
pacted together as any in the animal kingdom. Especially 
notable is one character which may be traced through all 
its divisions. The somites, or segments of the body, are 
in a numerical bondage ; they are never allowed to exceed 
twenty-one. That might not seem wonderful were it not 
that, in the segmented appendages of these same animals, 
there is frequently shown the most contemptuous in- 
difference to arithmetical restraints. 

As to the mystic number twenty-one, though it is never 
transgressed, the chance spectator will never find it fully 
developed for straightforward counting and ocular demon- 
stration. It is only discoverable by inferences and 
comparisons. Always some of the segments are in more 
or less complete coalescence. This fusion might lead to 
confusion, did not the following rule provide a guiding 
light. Wherever a segment can be definitely proved to be 
single, it never bears more than a single pair of appendages ; 
elsewhere, then, the presence of two or more pairs of 
appendages in apparent attachment to a single segment 
may safely be taken to imply that such a segment is in 
reality composite. Moreover, composite segments which 
have lost their appendages present no great difficulty, 
because they can be compared with corresponding segments 
which in other genera and species have retained their 
Often, in a male crab, the pleon or tail- 



part has such an unfurnished compounded segment, which 
plamly tallies with separate appendage-bearing segments 
in the other sex. When, therefore, we read of a genus in 





A. Jlemimerus lalpoides%. 
B. Hem 



D. Dipeltis carri (from Srliuchert). 
■nerus talpoides ? . 



which the male pleon has five segments and the female 
seven, it does not mean that nature has been more stingy 
to one sex than to the other, but only that in the mascuUne 
tail three segments have been soldered into one. With 
regard to the last segment, or telsou, there is this 
difficulty : it never has distinct appendages. Consequently 
its character has been aspersed, as though it were not a 
segment at all, but only a caudal excrescence— Uke the 
child which fancied itself a first-class carriage, whUe its 
playmates regarded it as nothing but a truck. The first 
segment, like the last, has had its , 

claim disputed. It is rarely free 
and independent. It carries the 
eyes, which some naturalists do not 
consider to be true appendages. 
Often, indeed, the eyes are "sessile" 
— that is, seated under the skin of 
the head, with nothing limb-like 
about them. On the other hand, 
the "ocular segment" is some- 
times movably articulated, and 
often the eyes are placed on jointed 
stalks, freely movable, and some- 
times of great length. Between the 
two debatable points there lie 
nineteen undisputed segments, 
verified by nineteen pairs of un- 
doubted appendages. These begin with two pairs of 
antennii3 and a pair of mandibles. It is a matter of 
convenience that throughout the Malacostraca every seg- 
ment should have its constant number, from the first to 
the twenty-first. Consequently, although in the sessUe-eyed 
division the first is always either wanting or undecipherable, 
that need not interfere with our reckoning the mandibular 
segment uniformly as the fourth. 

Here it should not be entirely overlooked that, though 
insects have no stalked eyes and have only one pair of 




c. Dipeliis diplodiscus. 



68 



KNOWLEDGE 



[Mabch 1, 1898. 



antennip, there are some among them, as H. J. Hansen* 
has shown, in which nineteen segments may be inferred 
exactly comparable to the last nineteen of the Crustacea 
Malacostraca. With the living forms of the male and 
female Hdinmcnoi talprAites (Walker) (a and b), regarded by 
Hansen as a wingless orthopterous insect, it can scarcely 
be uninteresting to compare the species THpeltis tUjilodisrns 
(Packard) (c) and Dipeltis rum' (Schuchert) (d\I fossils 
derived from the lower Carboniferous system, and placed by 
those authors among the entomostracan Apodidae. The 
entomologists now, with some reason, claim these fossils 
for their own, so that the common ancestors of insects and 
Crustacea remain as heretofore the phantoms of an un- 
discovered past. 

Reverting to our more immediate subject, a remark must 
be made on the mandibular segment. Owing apparently 
to that predominance which the jaw so often asserts in the 
affairs of life, this segment, not content with its nineteenth 
or other fractional share of the back, has spread itself in 
an obtrusive and in what might be called an overbearing 
manner. It assumes the title of carapace, or cephalotho- 
racic buckler. It is no doubt a valuable shield, but, like 
other saviours of society whose natural motto is " L'etnt, 
cent moi," the carapace of the crab sometimes takes leave 
to pose as if it were the whole animal. Of this an extreme 
example is afJ'orded by the Californian Ciyptolitlmhs ti//ncu3, 

of which a portrait by 
. ^'. Stimpson is here pre- 

.'^ ' ' , sented. As will be 

perceived, the great 
shield, in dorsal view, 
completely hides all 
the working members 
of the organism except 
the little twinkling 
eyes. 

The ten pairs of ap- 
pendages which follow 
the mandibles are objects of study of almost inexhaustible 
interest, not only because of the variety of form and function 
they exhibit in any one specimen, but because of the sur- 
prising variety of that variety as we pass from group to group. 




CnipioUlhudifS tiipiriis. (Dorsal vi 



tion. It will be easily understood that this diversity of 
function is matched by some diversity of form, and the use 
of distinctive names, such as maxills, maxillipeds, and 
trunk-legs, becomes indispensable. Some, in fact, are a 
kind of jaws — organs of the mouth — while others are a kind 
of arms or legs — organs of the trunk ; but the curious thing 
is that the middle pairs may be either one thing or the 
other, according to the group which owns them. The 
term "maxillipeds," or jaw-legs, enshrines the idea that 
these appendages, though used as jaws, are nothing but 
modified legs ; and the corresponding term " gnathopods," 
with the same meaning, hints at legs which are longing 
to be jaws. The hypothesis we have to consider is that 
all the appendages, including, with those already mentioned, 
the six pairs belonging to the pleon, are modifications of 
one original pattern. Between the primitive simplicity 
to be expected of such a pattern and the complicated 
structure observable in a crab's maxill*, it might at first 
sight seem hopeless to find the requisite connecting links. 
But extended comparison of features difficult to interpret 
with those that are common and commonplace has long 
ago brought out a sort of ground-plan of a crustacean appen- 
dage. According to this it principally consists of a stem 
and two branches. Three joints are perhaps the normal 
number for the stem, but it often displays only two, and 
occasionally only one. The joints of the branches are 
indefinitely variable in number. But, limiting ourselves 
for the present to the Malacostraca, it may be said that, in 
the organs of the mouth and in the limbs of the trunk, 
the inner or main branch of an appendage shows a 
preference for not exceeding five in the number of its 
joints. Add these to two in the stem, and entrust the 
seven to the plasticity of nature, and then see what will 
follow. A man has only to look at the noses and chins 
of his friends and neighbours to know what may be 
expected from modifications of shape and size. 

Imagine, then, a primitive limb of seven approximately 
uniform joints. In all but the last of these room must be 
found for the retractor and extensor muscles. For 
firmness of attachment to the trunk it may generally be 
convenient that the first joint should be short. The last, 
which does not require muscles, may be thinner than the 




a. Talifnis. b. Porcellio. c. Crangoii. d. Primiio. e. Aura. f. Phronima. g. Sphi/rapus. h. Potamohius. i. Ati/a. 



Among the functions more or less generally allotted to 
them may be reckoned those of tastmg and pasting, biting 
and fighting, grasping and clasping, walking and a kind of 
inarticulate talking, swimming, burrowing, house building, 
besides the automatic services which they render to the 
eggs in the brood pouch and to the animal's own respira- 

* " Contributions to the Knowledge of tlie Insect Fauna of 
Camerun." Eiitomol. Tidsk-er., PI. II., Figs. 1, 2, 1894. 

t Proceedings U.S. JSational Museum, Vol. XIX., PI. LVIII , 
Figs. 4, 6, 1897. 



rest. Being in frequent contact with external surfaces, it 
may acquire a hardened apex and become claw-like, or, 
for purposes of navigation, it may assume a broad, flat, 
blade-Hke appearance. The other joints will certainly 
not for ever maintain uniformity of length, and those 
which are longer will at least sometimes have a pro- 
portionate increase in breadth. By the course thus indicated 
we arrive at the ordinary leg of an ordinary amphipod, 
such as a sandhopper {see Fig. a), or that of an ordinary 
isopod, such as a woodlouse {see Fig. i), or that of a 



March 1, 1898.] 



KNOWLEDGE. 



69 



Ci-ani/on, an ordinary shrimp (sec Fig. c). But besides 
being lengthened and widened, the joints may be variously 
sculptured, as in the fifth joint of the next specimen, 
which represents the uncommon leg of an uncommon 
amphipod (vci Fig. dt ; or one joint maybe outdrawn at its 
apex to overlap the next, thus producing various forms of 
what is known as a chela or claw. In Fig. < the fourth 
joint is prolonged ; in Fig. / the fifth joint. These are 
two pecuUar forms among the Amphipoda. The next 
example shows the quaintly shaped leg of a deep-sea 
isopod, where the so-called " thumb " is on the sixth joint, 
though, owing to coalescence, it looks like the fifth. The 



the legs which come next to them, and the same may 
be said of the third maxillipeds in the Decapoda. But 
whether the appendage be adapted for eating, grasping, 
digging, or walking, its form can easily be referred to a 
simple linear original, and this applies also to the maxillfe 
and the mandibles, although in them the leg-like or linear 
pattern has become strangely disguised. 

The typical appendage was spoken of as consisting 
principally of a stem and two branches. Other appur- 
tenances of the stem must be left for future notice, but 
the second or outer branch claims more immediate atten- 
tion. As we have seen, it may remain entirely undeveloped. 




/. Swimming Foot of Amphipod. Jc. First Antenna, Liljelorgio. I. Tail-Foot, Apseude-i. m. Maxallipeds, 3, 4, Feneius. 
n. o. p. Slaxillipeds, 2, 3, and following limb, Sorialla. q. Le^ of Lepas. 



following figure shows the same thing in the more familiar 
leg of the river crayfish. Sometimes the joints are attached 
to one another, not end to end, but at various angles, as in 
the leg of a tropical prawn (st- I'ig. /), which has thumb and 
finger furnished each with a brush of long hairs, in nature 
as useful as they are beautiful. Of the limbs here shown 
none have the outer branch developed ; seme have over 
the first joint an expansion called a side-plate ; some have 
gills or breathing organs attached to them ; most have 
some sort of garniture of hairs and spines ; but these 
details are omitted as foreign to our present purpose. 
Most of the figures are considerably magnified portraits ; 
that from the crayfish is much reduced. 

Crayfishes, lobsters, prawns, and shrimps, all belong to 
the Ik'capoihi marrura, the ten-footed long-tailed tribe. 
In these the muscular pleon or tail part, through its 
strong development, possesses a commercial value and 
cannot escape observation. The crabs, on the other hand, 
which have no meat to boast of in the flexed and flattened 
pleon, are often erroneously supposed to be devoid of tails. 
That they are not open to this reproach is obvious, since they 
form the ten-footed short-tailed tribe, Iknipoda brachi/iini. 
But be the tail short or be the tail long, all these stalk- 
eyed creatures agree in having, after the mandibles, two 
pairs of maxillie and three pairs of maxillipeds and five 
pairs of peds, pods, feet or legs. In this respect one of the 
sessile-eyed groups— the highly curious Cumacea — agrees 
with them. But the sessile-eyed isopods and amphipods 
have, instead of three pairs of maxillipeds and five of legs, 
one pair of maxillipeds and seven pairs of legs. Upon com- 
parison, then, it becomes perfectly clear that the appendages 
of the eighth and ninth segments are strictly homologous 
throughout the Malacostraca. We may call them maxilli- 
peds or gnathopods or trunk-legs, according to their difi'er- 
ences of form and function, but they are none the less 
essentially equivalent structures. In some of the Amphi- 
poda and Isopoda the maxillipeds are more leg-like than 



At other times it invites observation, as in the shrimp- 
like Schizopoda, which bear this name of " cleft-legs " 
because their trunk-limbs display both branches. But 
really there are very few crustaceans which do not, in one 
appendage or another, display them both. Throughout 
the Amphipoda the first three pairs of appendages of the 
pleon have a very uniform character. They almost in- 
variably consist of a two-jointed stem and two subequal 
lash-like branches. The lashes are constituted of a great 
many small similar joints, each furnished with a couple of 
long hairs, and they are generally efl'ective swimming 
organs {sef Fig. j). In these pleopods, or legs of the 
pleon, one may imagine that one sees a pattern of 
crustacean appendage more primitive than the leg-like 
one before suggested. Both pairs of antennae usually end 
in lashes. The first pair often has two (see Fig. A-). 
Occasionally, as in the isopod Ajisfwhs, there are two 
such lashes at the opposite extremity of the animal, in the 
last pair of tail-feet {.'^et- Fig. /). Kepeatedly in the 
triple maxillipeds of the Decapoda, while one branch is 
pediform, the other has a terminal lash (see Fig. m). In 
the Schizopoda this structure is to be found not only in 
the two pairs of limbs which are equivalent to the second 
and third maxillipeds {^ee Figs. «, o, p), but in all the 
five pairs which follow {see Fig. q), these being succeeded 
by five pairs of pleopods, each with two lash-like branches. 
One abnormal case is often quoted, in which the eye-stalk 
of a crayfish developed into an antenna-like lash. This 
has recently been matched by an equally abnormal case in 
which a " trunk-leg" has been developed on the pleon of 
a crab. 

From a wide-reaching subject enough has perhaps been 
culled to lead the indastrious beginner into an engaging 
path of inquiry — the comparative anatomy of Crustacea. It 
will be strange if he can avoid drawing the conclusion that 
at least all the Malacostraca are of a common origin. It 
will be strange, too, if the cirri, or legs of the barnacle, 



70 



KNOWLEDGE 



[March 1, 1898. 



with their stem and two lash-like branches {see Fig. q), do 
not awake in him at least a suspicion that the crustacean 
family is not only not confined to a few articles of domestic 
consumption, but may have ramifications even beyond the 
bounds of the Malacostraca. 



NOTES ON COMETS AND METEORS. 

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

Comets. — Pons-Winnecke's comet at the beginning of 
March will enter the head of Capricornus and pass between 
the bright stars a and /3 of that constellation ; but as these 
objects will be only forty degrees west of the sun, and rise 
about two hours before him, there will be but a slender 
prospect of observing the comet. The distance of this 
object from the earth is now increasing, and it is not likely 
to be seen again in ordinary telescopes until the early part 
of 1904. 

Comet II. 1892 (Denning).— In Ast. Nac/i. 3472, Dr. 
Steiner, of O'Gyalla, Hungary, gives a definite orbit which 
he has derived for this object from a discussion of one 
hundred and eighty-six observations. Though a very 
small, faint comet, it was visible for a long period, and its 
positions were secured during the ten months from 1892, 
March 19th, to 1893, January 12th. Dr. Steiner con- 
cludes that the orbit is hyberbolic, for, with the excentricity 
at 1-000345, the sum of the squares of the residuals is 
103-2" for an hyperbola, and 279-5" for the parabola. 
The observations near the middle of the series, in the 
summer of 1892, exhibit rather large residuals, and Dr. 
Scheiner regards this as unsatisfactory. But the comet 
was difficult to observe at that time owing to the twilight, 
and to its faintness, due to great distance from the earth ; 
for at the middle of June the comet was separated from us 
by an interval of two hundred and seventy millions of 
miles. The path of the comet was nearly vertical to the 
ecliptic, the inclination being eighty-nine and three-quarter 
degrees. Dr. Scheiner's definitive elements are : — 

T 1892, May 11-201935 M.T. Berlin. 

ir 22° 45' 42-40" 

n 253° 25' 50-92" 

I 89° iV 54-10" 

log. ,]. ... 0-2946197 

e 1-000345 

Meteors. — Though the shower of Leonids in 1897 was 
not very brilliant, and completely obscured by clouds at 
the majority of stations on the mornings of November 
15th and 16th, it returned with fair activity on those dates. 
There is little doubt, however, that the earth did not 
encounter the really dense portion of the stream, but it is 
difficult to specify what strength is fairly representative of 
the main swarm, and a certain standard (or rate of appari- 
tion) will have to be adopted to express it. The richest 
part of the current is probably not a sudden development, 
but due to gradually increasing abundance along a con- 
siderable stretch of the orbit. It is important to ascertain 
the time when the earth encounters that section of the 
stream in which the meteors begin to be thickly congre- 
gated. In 1833 there were one thousand meteors per 
minute, while at about the period of maximum frequency 
on November 13th, 18G6, there were one hundred per 
minute for one observer. What, therefore, will be the 
rate of appearance assumed for the fore region of the 
main swarm ? Perhaps ten meteors per minute might 
satisfactorily represent it, for this would give six hundred 
per hour, it being understood that the figures are for one 
observer watching a clear, moonless sky with the radiant 
at a fair altitude. It is certain from the conditions of the 



case that the relative intensity of the stream at different 
parts can only be ascertained after many cyclical returns 
of the swarm, for the earth is only involved in it for a 
short time once a year, and in the interim of successive 
encounters a vast range of the current passes the node 
without recognition. 

Now that the efi'ort is being made to photograph the 
group of Leonid meteors in space, it might be as well to 
endeavour to get an impression of the parent comet. On 
March 10th the comet will be certainly less than two 
liundred millions of miles distant, and possibly less than 
one hundred and fifty millions, whereas the meteoric 
swarm will be about five hundred and sixty-eight millions 
distant on the same date. In view of the fact that the 
comet is more highly condensed and probably far more 
luminous than its accompanying meteoric stream, the pro- 
spect of detecting it is much more favourable. Towards the 
close of the present year, however, the comet will approach 
much nearer to the earth than it is at present, and no 
doubt some special efforts will then be made to redetect it. 

Fireball of 1898, January 21st. — In the twilight of 
Friday evening, January '21st, at 5h. 32m., one of those 
large fireballs which occasionally burst out and illuminate 
sky and landscape with startling brilliancy, was observed 
at a great many places in the South of England, and in 
some parts of Ireland and Wales. A considerable number 
of descriptions of the object were published in the news- 
papers, and if, as usual, the writers failed to record the 
exact position of the meteor's path and its duration of 
flight, they one and all testified to the astonishing brilliancy 
of the phenomenon. Not many stars were visible at the 
moment of the meteor's descent, so it was diflScult to fix 
its apparent course with the necessary precision. But 
several of the observers were fortunate enough to obtain a 
good \aew of it, and recorded the path as accurately as 
circumstances permitted. From thirty-three accounts 
which I have compared together, it appears certain that 
the fireball traversed a very long path from east to west 
over the south coast of Enijland. Observers in London 
and that district say that the object first appeared at a 
great altitude in south-east or south, and disappeared in 
south west ; while spectators in the western counties 
describe the motion as from east or east by south to south- 
west, or south-west by south. The flaming nucleus was 
not so large as the moon, but was, according to several 
reports, about twelve or fifteen minutes of arc in diameter, 
but its brightness exceeded that of the full moon. The 
colour appears to have varied, and observers are by no 
means agreed in their estimations, but the head seems to 
have been yellowish and the train bright green and purple. 
The meteor burst before vanishing ; and it travelled, not 
with that very slow, sailing flight which is often charac- 
teristic of the largest fireballs, but with moderate velocity, 
and its entire visible course probably occupied seven seconds. 
One person, however, says it lasted thirty seconds ; another 
estimated the duration as nearly five minutes ! The best 
estimates vary from three to seven seconds, but most of 
the observers only caught the meteor after it had akeady 
traversed a part of its course, and when it was descending 
at a low altitude in the south-west. 

The fireball when first seen appears to have been 
eighty-two miles above a point five miles south of Croydon 
in Surrey. Moving to the south-west by west it passed 
over Peterstield, Lymington, and St. Alban's Head, and 
disappeared at a height of twenty-five miles over the 
English Channel some thirty-five miles south of Eddystone 
Lighthouse. Its length of path was two hundred and 
thirty-five miles, and velocity about thirty-four miles per 
second. The radiant point was in the north-east region 



March 1, 1898.] 



KNOWLEDGE. 



71 



of Cancer at 180° f 30°, in azimuth about 31^ north of 
east, and altitude 14' at the time of apparition. The 
fireball was probably a member of a meteoric shower seen 
at Bristol in 18s7-!l, January 25th to February 1st, at 
131° + 32°. A fireball seen in 1877, -January 19th, may 
also have been derived from the same system, for its real 
path, computed by Prof. Herschel, presents a striking 
resemblance to that of the recent meteor, as follows : — 

Ueierlit Height „ .. „^| ,. 

at first, at end. ^''*^- Velocity. Position of 

Miles. Miles. Miles. Miles. «»«■»»»• Path. 

82 25 2:« M Vlff + Sff Smith of Enfluiul. 

75 W 230 :« lM«+27>' | ^'0?'!?.^.,^"""' 

Two large and brilliant meteors were observed on the 
night of Simday, February 20th, 18!)s, at 8h. 54m., and 
lOh. 20m., and particulars ofthesewill be given next month. 



Jttn.21,lS98 
Jan. 19, 1877 



THE FACE OF THE SKY FOR MARCH. 

By HERnERT Sadler, f.r.a.s. 

SUNSPOTS may occasionally be observed on the 
solar disc. 
Conveniently observable minima of Algol occur 
at midnight on the 1st, at 8h. 50m. p..m. on the 
4th, and at lOh. 32m. p.m. on the 24th. 

Mercury is too near the Sun to be observed this month, 
being in superior conjunction with the Sun on the 16th. 

Venus is too near the Sun for the observer's purposes, 
and Mars is also practically invisible. 

Jupiter is an evening star, and is excellently situated 
for observation, being in opposition to the Sun on the 
25th. On the 1st he rises at about 8h. p.m., with a 
southern declination at noon of 1° 52', and an apparent 
equatorial diameter of 43i ". On the 12th he rises at 
7b. 9m. p.m., with a southern declination of 1° 22', and an 
apparent diameter of 44". On the 22nd he rises at 
6h. 24m. P.M., with a southern declination of 0° 51', and 
an apparent diameter of 44[". On the 31st he rises at 
5h. 44m. P.M., with a southern declination of 0° 24', and 
an apparent diameter of 44 j". During the month he 
describes a retrograde path in Virgo. 

Saturn does not rise till just before midnight on the 1st, 
so we defer an ephemeris of him till April, and an 
ephemeris of Uranus is omitted for similar reasons. 

Neptune is an evening star, being in quadrature with the 
Sim on the 10th. On the 1st he souths at (ih. 37m., 
with a northern declination of 21° 48', and an apparent 
diameter of 2V'. On the 31st he souths at 4h. 40m. p.m., 
with a northern declination of 21° 45'. He is almost 
stationary in Taurus during the month. 

There are no very well marked showers of shooting stars 
in March. 

The Moon is full at 9h. 29m. a.m. on the 8th ; enters 
her last quarter at 7h. 48m. p.m. on the 15th ; is new 
at 8h. 37m. a.m. on the 22nd ; and enters her first quaiter 
at 7h. 40m. a.m. on the 30th. Some of the small stars in 
the Pleiades will be occulted on the evening of the 26th. 



C!)tss Column. 

By C. D. LocooK, b.a. 

Communications for this oolnmn should be addressed to 
C. D. LococK, Burwash, Sussex, and posted on or before 
the 10th of each month. 

Solutions of February Problems. 

No. 1. 

(W. Clugston.) 
1. Kt to B4, and mates next move. 



No. 2. 

(S. Loyd.) 

1. P X B (becoming a Knight), K x Kt. 

2. Kt to QKtG, anything. 

3. P to R8, mate. 

White gets a Knight in order to be able to place it 
between his RP and the Black Bishop on his next move. 
No correct solutions have been sent, but the problem was 
well worth solviuL,', as all Mr. Loyd's are. 

Correct Solutions of No. 1 received from G. G. Beazley, 
II. Worsley Wood, W. de P. Crousaz, J. MRobert, 
A. E. Whitehouse, H. W. Elcum, Mrs. C. F. Giddings. 

Capt. Forde.—U 1. Kt to B8, K to B4, dis. ch. 

F. A. Curtis.— 1. B to K6 is met by Kt to K7. In 
No. 2, after 1. Kt to B4, BxP; 2. Kt to K2, the King 
moves and escapes mate. 

//. TC. Elcum. — Your solution of No. 2 fails as above. 

.T. n. (York).— See above. In No. 2, if 1. P to Kt8 
(Queens),. B to Kt2, and the Queen cannot play to KtG. 
But the Bishop may also safely play to Q4 or K5, though 
not elsewhere. A note appended to the January puzzles 
gave warning that a " liberal interpretation " of the laws 
of the ,1,'ame was required for their solution. As a matter 
of fact, the law says nothing as to the colour of the piece 
to be chosen. If, therefore, White selects a Black Rook, 
lilack has a perfect right to use it for Castling purposes. 
We are glad to hear that you appreciate the February 
Number. 

H. Worxh'i/ Wiind and A. E. Whitehouse. — In answer to 
1. P to Kt8 (becoming a Queen), Black moves his Bishop 
to Kt2 or Q4 or Ko, and there is no forced mate in two 
more moves. If he move elsewhere there is. 

F. ir. A. de Tabeck (Rome). — Many thanks for your 
appreciative card. 

/'. U. Fotheringham. — The massacre suggested is too 
terrible to think of. Could you not be contented with 
3. PQR3, and less bloodshed ? 



PROBLEM. 

From the SUmdard. 

Black (2). 






wmi 



,?.. '^m»- ^m Ml 



White (4). 

White mates in three moves. 



We propose this month and next to try the effect on our 
readers of some very full analysis. For this purpose we 
have selected a short game of nineteen moves, played on 
Board No. 1 in the Kent c. Sussex correspondence match 
last year. Our analysis is compiled from notes made at 
the time. 



72 



KNOWLEDGE. 



[March 1, 1898. 



Part I.- 
Whitb. 

1. P to K4 

2. KKt to B3 

3. B to Kt5 

4. P to Q4 

5. P to K5 

6. Castles 

7. B to E4 (h) 

8. BxKt 

9. KtxP 

10. Kt X Kt (d) 

11. Q to K2 

12. Q to K3 (/) 

13. Q to E7 (h) 



-The Opening. 

Black. 

1. P to K4 

2. QKt to B8 

3. Kt to B3 

4. PxP 

5. Kt to K5 

6. P to QR3 (/() 

7. Kt to B4 

8. QPxB 

9. Kt to K3 (<■) 

10. BxKt 

11. Q to R5 («>) 

12. Castles {;i) 



Notes. 

(a) Not to be found at this particular stage in any book 
on the openings. The time-honoured move is 6 . . . 
B to K2. 

(/)) This loses a move. 7. BQ3, or B to B4, would be 
answered by 7. . . . P to Q4. But the best course seems 
to be 7. B x Kt, QP x B ; 8. Kt x P (or a, b), B to K2 ; 
!). B to K3, Q to Q4 ! 

(a) 8. (.' to K:.', QB to B4 (or (i.) ) [not 8. ... Q to Q4, 
on account of P to QB4, now or later] ; 9. B to K3, Q to 
Q2 (9. Kt X P, Q X Kt !) ; 10. Kt x P, Castles (QR) ; 11. P 
to KB8, etc. 

(i.) 8. . . . Kt to B4 ; 9. R to Qsq, B to Kt5 ; 10. B 
to K3, Kt to K3 (or 10. . . . Q to Q4) ; 11. P to B3, 
Q to Q4, or KB to B4, etc. 

(b) 8. R to Ksq, Kt to B4 ; 9. Q x P (or 9. Kt x P, Kt to 
K3), Q X Q ; 10. Kt x Q, Kt to K3, etc. 

(c) By a transposition of moves the position in a match 
game, Morphy r. Lowenthal, has been reached. Lowenthal 
played this move, which is much better than 9. . . . B to 
K2, as recommended by Morphy, Salvioli, and Steinitz. 
The two latter authorities give 9. ... B to K2 ; 10. QKt 
to B3, Castles ; 11. B to K3, P to KB8 ; apparently over- 
looking the powerful reply, 12. Q to K2, threatening Kt x P. 

(d) This and his nest move were played by Morphy 
against Lowenthal. If, instead, 10. B to KB, Kt x Kt ; 
11. B X Kt, QB to B4 ; 12. P to QB3, Q to H5, with a good 
game. But, on account of Black's 11th move in the actual 
game, we are inclined to prefer 10. KKt to B3, Q x Q ; 
11. E X Q, BK2 ; though Black can develop afterwards by 
Kt to KBsq, and B to KB4. 

(<■) Much stronger than either 11. ... B to QB4, as 
played by Lowenthal, or 11. . . . B to K2, as recom- 
mended by him. The Black Queen is never dislodged from 
this powerful position. Black now threatens B to B5. 

(/) Evidently intended to prevent Castling (QR), and in 
a minor degree, perhaps, to support the entry of a Knight 
at QB5. But in other respects it loses time. 

((/) A bold course, but 12. ... B to K2, followed by 
Castles (KE), andQR to Qsq, would leave the Queens side 
pawns unprotected. 12. ... Q to QB5 ; 13. Kt to E3 
(best), B X Kt ; 14. Q x B, leads to a draw, as Black cannot 
take the BP on account of B to Kt5. Another plan would 

be 12 E to Qsq ; 1 3. Q to E7 (?), B to Bsq ; 14. Q to 

Kt8, Q to K2. 

(h) This su))jects him to a strong attack. Another 
course would be— 13. Kt to Q2, B to Q4 ; 14. Q to E7 
(or a), P to QB4 ; 15. Kt to B3 (if 15. E to Qsq, Q to 
05!), BxKt; 16. PxB,QtoE4! 

(a) 14. P to QB4, B X P ; 15. P to KKtH, Q to Kt5 ; 
16. KtxB, QxKt; 17. Q to R7, B to B4 ; 18. Q to 
R8ch, K to Q2 ; 19. Q x KtP, Q to Kt4 [or, perhaps, 



19. ... B to Kt3 ; 20. E to Qsqch, K to K3 ; 21. E x R, 
E X R ; 22. B to K3, B x B ; 23. P x B, Q to K5 ; with 
some advantage] . 

We reserve the rapid and interesting finish for next 
month. 



CHESS INTELLIGENCE. 



The following team has been chosen to represent the 
British Isles in the Cable Match '■. the United States, on 
March 18th and 19th : — Messrs, Atkins, Bellingham, 
Blackburne, Bum, Caro, Jackson, Jacobs, Locock, MUls, 
and Trenchard. Reserves : Messrs. Cole and Wainwright. 
Messrs. Caro and Trenchard are new to the match, while 
Messrs. Blake, Cole, and Lawrence, who were in last 
year's winning team, are not playing on the present 
occasion. 

The order of the team is not yet decided on, but it is 
fairly safe to predict that the first three letters of the 
alphabet will be well to the fore. 

The Hastings Chess Festival last month met with its 
usual success. Messrs. Blackburne, Bird, (lunsberg, and 
Janowski gave simultaneous exhibitions, and took part in 
consultation games against each other with amateur 
partners. 

Messrs. Pillsbury and Showalter have begun their second 
match for the championship of the United States. It will 
be remembered that their former encounter last year 
resulted in a hard-earned victory for Mr. Pillsbury by 
10 games to 8. 

On January 24th the British Chess Club defeated the 
St. George's Chess Club rather decisively by 8 games to 2, 
the latter score being made up of 4 drawn games. 



KNOWLEDGE, PUBLISHED MONTHLY. 



Contents of No. 147 (January). 

The Karkinokosm, or World ot 
Crustacea. By the Her. Tbomos 
E. E. Stehbing, M.A., F.B.S., 

F.L.S. (!lliis(rntcd) 1 

A Drowned Continent. By E. 

Lrdekker, b.a., f.b.s 3 

Is Weatherufiected by the Moon ? 
Bv Alex. B. McDowall, m.a. 

(Illustrofed) 5 

Serpents and bow to recognize 

them. By Lionel Jervis 7 

The I'risumtic Camera daring 
Total Echpses. By Wni.Shackle- 

ton, F.B.A.S. aihiHtrated} 9 

Notes on Comets and Meteors. 

Bv W. F. Uenninp, k.k.a.s 10 

Richard Proctor's Theory of the 
Universe. ByC.Easton. (niiis- 

traUd) 12 

British Oi-nithological Notes 14- 

Science Notes 15 

Lettere 16 

Notices of Books (Illustrated) ... 18 

Books Received 21 

Obituary 21 

Bobinical Studies.— I. Vaucheria. 
By A. Vanffhan Jennings. F.L.S. , 

F.G.S. {UUshnled) 21 

The Face of the Sky for January. 

By Herbert Sadler, f.r.a.s 2X 

Chess Column. By C. D. Locock 23 

PuTE.— Photographs of "Reversing 

Laver" »nd Coronal Ring. 



Contents of No. 14B (February). 

PAGE 

The Floor of a Continent. By 

Grenville A. J. Cole, h.k.i.a., 

F.G.S. (filusfrofcd) 25 

Economic Botany. By John B, 

Jackson, a.l.s., etc 28 

From a Hole in the Mndflats. By 

Harry F. Witherby, F.Z.S., 

M.B.o.r. (IU«str<i(«d) 29 

Liqnid Fluorine. By C. F. 

Townsend, F.c.s. (Illustrated) 31 

Letters 33 

British Ornithological Notes 36 

Science Notes 37 

Notices of Boobs 37 

Total Solar Eclipse, January 22nd, 

189S 38 

Photograph of the Spiral Nebula 

Messier .33 Trianguli. By Isaac 

Roberts, D.sc, f.r.s 39 

Moon in EcUpse, January 7th, 

1898. ByL. PaJrton 40 

The Spectra of Bright Stars. By 

E. W. Maunder, F.B.A.S -W 

Ancient Bed Deer Antlers. B.v 

B.Lydekker.B.A., F.B.S. (filus.) « 
Notes on Comets and Meteors. 

By W. F. Denning, F.B.A.S 4C 

The Face of the Sky for Febnuiry. 

By Herbert Sadler, f.r.a.s. 47 

Chess Column. By C. D. Locock 47 

Plate. — Spiral Nebula Messier 
33 Trianguli. 



The vearly bound volumes of Kkowledoe, cloth gilt, 8s. 6d., post free. 
Bin<fine Cases, Is. 6d. each ; post free. Is. 9d. 

Subscribers' numbers bound (including case and Index), .is. 6d. each volume. 
Index of Articles and Illustrations for 1891, 1892, 1894, 1895, 1896, and 1897 
an' be supplied for 3d. each. 



"Knowledge' Annual Subscription, throughout the world, 
8s., post free. 

Communications for the Editors and Books for Review should be addressed 
Editors, " Knowledge," 336, High Holbom, London, W.C. 



April 1, 1898.] 



KNOWLEDGE. 



73 




Founded in i88i by RICHARD A. PROCTOR. 



LONDON: APRIL 1, 1898. 



CONTENTS. 



Economic Botany. B_v John E. Jackson, a.i.s., etc. 

The Structure of Ireland. Bv Grentille A. J. Cole, 

il.B.I.A., F.G.S. (Illustrated) 

The Sea-Otter and its Extermination. By R. LyuEEKEit, 

B.A., F.R.S. {Illustrated) 
British Ornithological Notes. Conducted by Habet F. 

WiTHEEBT, F.Z.3., M.B.O.U 

Letters :— David Flanert ; "W. E. Beslet 

British Bees. — II. By Feed. Exoce, f.l.s., f.b.s., etc. 
[Illustrated) ... " 

In the Moon s Northern Regions. By Arthur Mee, 
F.B.A.s. (Plate) ' 

Notices of Books 

Short Notices 

Books Ebceited 

Stars having Large Proper Motion. By E. C. Pickebing 
The Level of Sunspots. By the Rev. Abthue East. 

(Illustrated) 

The Evolution of the Venom-Fang. By Lioxel Jeetis. 

(Illustrated) ' 

Notes on Comets and Meteors. By W. F. Denkino, 

F.E.A.S. ... 

The Face of the Sky for April. By Hekbeet Sadlbb, 

F.B.A.s 

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



PAGS 

73 



ECONOMIC BOTANY. 

By John R. .Jackson, a.l.s., etc., Ka'per af the Museums, 
Roi/al (i aniens, Keiv. 

IN our introductory remarks on this subject (Knowledge, 
February, 1898) we drew attention to the fact that 
the Kew Museums from their foundation were 
unique in their character, and at the present time 
are far and away the most important institutions of 
the kind throughout the world. It will be best, therefore, 
to take these collections as the basis of our remarks in 
succeeding papers, following the arrangement of the natural 
orders as there adopted, which is based on the system of 
the Geiiern I'lantarum of Bentham and Hooker. By this 
means we shall be able to prove what we said in our intro- 
ductory remarks on the distinct economic character of 
certain natural orders and their importance over others in 
supplying the wants of man. In treating our subject in a 
scientific rather than a commercial manner, the advantages 
will be that those of our readers to whom the Kew Museums 
are available will have object lessons before them which 
they will find no difficulty in applying to their own indi- 



vidual requirements, and occurring in the same sequence 
as here set down. Other advantages will be that the habits 
of the plants constituting each natural order will be briefly 
stated, as well as their geographical distribution. Of 
necessity these descriptions must be brief, and only the 
principal products can receive treatment ; more attention, 
of course, being given to those of greater than those of 
lesser commercial value. 

Ranunculace.e. — The type of this order is the buttercup. 
The plants which form the group are herbaceous. Very 
few have woody stems. They have a wide geographical 
range, but are more abundant in cool climates. Their 
general properties are acrid and poisonous, which is well 
exemplified in the common aconite or monkshood(.^co)ij(M»i 
iKipellus L.). The order is chiefly valued for its medicinal 
products, the principal of which is the aconite just referred 
to. It is a perennial plant found in sub-Alpine pastures, 
and damp, shady places in hilly districts, particularly in 
the Alpine chains of Europe, as well as in the Himalayan 
range, where it extends from ten thousand feet elevation 
up to the limit of vegetation. Though it occurs in some 
counties of England and Wales, it is scarcely considered 
a native. 

The aconite is valued economically both for the rhizome, 
or rootstock, and for the leaves, both of which contain the 
alkaloid neon i tine, though the rhizomes are said to be six 
times stronger than the leaves. The rootstock is moat 
active in the winter and early spring, and for medicinal 
purposes should be collected at those periods. The fresh 
rhizome varies in size from three to sis inches long, broad 
at one end, and tapering to a fine point. It descends 
perpendicularly into the ground, and gives off numerous 
rootlets. It has an earthy odour, and a taste which is 
slightly bitter at first, but which is succeeded in a few 
minutes by a burning sensation, and a tim,'ling or numb- 
ness in the lips, cheeks, or tongue. The market is mostly 
supplied with aconite root from the wild plants, but some 
of the dried root is imported from Germany. Though 
aconitine is one of the most virulent poisons known, it is 
an extremely valuable medicine. Tincture of aconite 
is much used for outward application to allay pain in 
rheumatic and similar affections. The accidents that 
sometimes occur from mistaking aconite root for horse- 
radish can only happen at the time when the plants are 
leafless, as the foliage of the two plants is very distinct ; 
and even then the tapering and dark-coloured root of 
the aconite is quite different in appearance to the long, 
cylindrical light-coloured root of the horseradish. Several 
other plants belonging to this order, natives chiefly 
of America and India, furnish useful medicines. The 
small black seeds known as fennel-flower seeds are also 
the produce of a ranunculaceous plant — Xinilla satira, an 
annual of the South of Europe. Levant, Egypt, etc. The 
common name is derived from the fennel-like odour the 
seeds have when fresh. In the East they are used as a 
carminative medicine and for flavouring curries, as well as 
to keep insects from woollen cloths. In France they are 
used as a spice. 

Magnoliace.e. — Trees or shrubs, many of them with 
handsome and fragrant flowers, found in North America, 
India, China, and .Japan. They possess bitter tonic and 
aromatic properties. The woods are of a light colour, even 
grained and easily cut. The two most important economic 
plants of the order are the star anise and the American 
tulip tree or white wood. The first, lUicium eerum, is a 
tree about twenty feet high, the fruits of which are com- 
posed of several carpels, and when fully ripe and dry they 
open and expand in the form of a star ; hence the common 
name. The whole fruit has a most agreeable aromatic 



V4 



KNOWLEDGE 



[Apbh, 1, 1898. 



odour and yields an equally aromatic oil. They are 
imported in considerable quantities from China into 
Europe, America, and India for flavouring liqueurs and 
spirits. The tree grows to a height of about twenty feet. 
The tulip tree or white wood, JArioihntlron tuiijiifeni, 
grows in its native country of America to a height of over 
one hundred feet. It grows well in England, and is a 
favourite tree in consequence of its peculiar-shaped foliage 
and tulip-like flowers. The wood is fine and even grained, 
very white, and free from knots, so that it is in very great 
demand both in America and in England for cabinet work, 
door panels, etc. In some trunks, however, the wood is of 
an even yellowish tint, and is known as canary wood. 

Most of the species of ^fnipiolin 3deld white and even- 
grained wood, which is much used for various purposes in 
the countries where the trees grow. 

Anonace.t.. — This is an important natural order of 
tropical trees and shrubs, noted for the aromatic and even 
pungent properties of some of its species. They are chiefly 
natives of tropical countries, and are perhaps best known 
for their edible fruits, such, for instance, as the sour-sop, 
Anonii muricata, a West Indian tree producing a fruit 
sometimes weighing upwards of two pounds. It is some- 
what oval in shape, of a greenish colour externally, and 
covered with prickles ; internally the pulp is white and 
has an agreeable slightly acid flavour. The sweet-sop, A. 
squamosa, is a native of the Malay Islands, but is cultivated 
both in the East and West Indies. The fruit is nearly 
globular, somewhat larger than a cricket ball, and is 
covered with projecting scales, or mammilhe, over which 
is a thick rind. The central portion is filled with whitish 
pulp, in which are embedded the numerous black shining 
seeds. The custard apple, or bullock's heart, Anona reticu- 
lata, is smaller than the preceding, and is somewhat 
irregularly heart shaped. It is a native of the West Indies, 
but is cultivated also in the East. The yellowish pulp is 
not generally so much liked as that of the preceding. The 
cherimoyer [Anona cJierimolia) is said to be the most deli- 
cious fruit of the order. It is a native of Peru, but is 
cultivated in the West Indies and other countries exclu- 
sively for the sake of its fruit. Like those of the other 
species the fruit is somewhat heart shaped, the outside 
covered with scales and the inside pulp of a yellowish pink 
colour. The aromatic character of the order is well illus- 
trated in the seeds of many of the species, as in Monodora 
i/ii/ristica, the numerous seeds of which are borne in large 
globular fruits. These seeds are remarkable for their 
distinct rumination, which, indeed, is a character of the 
order generally. What is known as negro or Ethiopian 
pepper is the fruit of X;/lopia (Kthiopica, a large tree of 
the West Coast of Africa. When ripe and dry, as they appear 
in the West African markets, the fruits are black and quill- 
like, arranged in bunches or clusters around a central axis. 
They are aromatic and strongly pungent, and are used by 
the natives for seasoning their food. Attempts have been 
made to introduce them into English commerce, but as 
they have no advantage over pepper or other condiments 
they have not succeeded. 

Menispermace.f,. — This is a group of climbing tropical 
shrubby plants, abundant in woods of Asia and America. 
In cross section the stems and roots show a very large 
development of the medullary rays, and the structure is so 
open or porous that the more slender stems are often so 
pliable as to be used for ropes. Another distinct character 
is the bright yellow, or greenish yellow, colour shown 
when the wood is freshly cut. Their properties are bitter 
and narcotic, and, in some cases, poisonous. The order is 
essentially a medicinal one, several of the species yielding 
valuable remedies, such as the )mrnra brave (Chondvo- 



demhiin tomentosum), a woody climber of Brazil and Peru, 
having a bitter taste but no smell, and it is used as a mild 
tonic and diuretic. Calumba root is another bitter tonic. 
It is the product of Jatecrrln'za laluwlia, a perennial 
climber of the forests of Mozambique and Quillimane. 
It appears in commerce in this country usually in dried, 
yellow-coloured, transverse slices, which have been cut 
when fresh, and are consequently shrivelled. Under 
the name of Cocculw Induus the berry-like fruits of 
Aniimirta jianiculata are sent in very large quantities 
to this country from India. They are poisonous, and 
the only use to which they are known to be put is in the 
preparation of ointments, chiefly for killing pediculi ; but 
it is said that they are also used in giving a bitter flavour 
to beer. The plant is a large woody climber, and the 
fruits are about the size of a large pea. 

Other medicinal plants in this order that may be men- 
tioned as more or less useful are the spurious jiareira 
bravd {Cisxiim/ii'lds pari'ira), a, slender woody climber found 
in tropical regions of both hemispheres, which has bitter 
and tonic properties ; and false calumba {Coscinium fenes- 
tratum), also a climber of Ceylon, Southern India, and 
Malacca, the wood of which is of a greenish yellow colour. 
It is a bitter tonic. 

Pjerberidacek. — This order consists of shrubs and 
herbaceous plants, mostly natives of temperate climates. 
The common barberry (Berlnris vulgaris) is the only British 
species of the order, the properties of which are acid and 
astringent ; a yellow colouring matter is also found in the 
woods. The most important economic plant is Po'loplnjUum 
pAtatum, a perennial of the United States and Canada, the 
rootstocks of which contain an active principle known as 
podophyUin, and much valued in medicine. 



THE STRUCTURE OF IRELAND. 

By Grenville a. J. Cole, m.r.i.a., f.g.s., Professor or 
Geolof/i/ in the Royal College of Science for Ireland. 

OWING to the isolation of Ireland, as compared with 
Scotland, its geological features have remained 
comparatively unknown, except to the oflicers of 
Government Surveys and the authors of certain 
careful and conscientious text-books. Headers of 
the latter are still apt, however, to skip the pages dealing 
with so remote an island, and to devote their earnest 
attention to the minuter details of purely English strati- 
graphy. 

Even now, when the finest line of channel steamers on 
our coasts runs between Holyhead and Kingstown, the 
visitors who throng these boats at certain seasons aim at 
little more than Killarney or the Giant's Causeway. The 
associations of the former place in summer are scarcely 
suited for philosophic speculation ; while the speculation at 
the latter place is mainly confined to the syndicate which 
has recently enclosed it, and which, after the manner of 
the enterprising Swiss, charges an entrance-fee for the 
inspection of its natural beauties. 

But no one who approaches Ireland can fail to be struck 
by certain of its physical features, notably the picturesque 
and even mountainous character of its coast. Ofl' Dublin, 
the clift's and the rugged little moor of Howth may remind 
us of Holyhead or Cornwall ; but on the south side of the 
bay the eye is caught by the still bolder promontory of 
Bray Head, the graceful cones of the Little and Great 
Sugarloaves, and the long range of the Dublin and Wicklow 
mountains, stretching sixty miles into the south, and rising 
two to three thousand feet above the sea. 

Or at Greenore we may enter on a sunny morning, to 



April 1, 1898.] 



KNO^A/•LEDGE 



75 



see the mists clearing from the granite peaks of Mourne, 
and the saw- edge of the Carlingford range already black 
against the sky. And we look farther up the sea-lough 
towards Newry, where the ground rises inland to form the 
plateau of Armagh, bearing on its back the volcano of 
Slieve GuUion and other giants of the moorland. 

To reach Belfast, again, we pass up the lough between 
the hills of Down and the far bolder and terraced masses 
of the Antrim coast, and rest at last against the quay, 
where the smoke of a busy commercial centre cannot blot 
out the great black crags that rise almost sheer above the 
town. 

Or, again, near Cork, where the foreground is lower, and 
something in the pleasant Falmouth style, glimpses are 
seen of those fine red-sandstone ranges that run from 
Waterford to Kerry, and form a backbone to all the 
southern coast ; while an approach from the Atlantic 
side, to Bantry, Cialway, or Donegal, would impress still 
more firmly on the traveller the mountainous nature of 
the country. 

Yet, start this traveller by rail from Gal way to Dublin, 
or from Cork to the sea again at Drogheda, and he will 
report that Ireland is a Hat country, with occasional 
bands of mountains on its margins. In the former case 
he will cross the Shannon in a broad prairie at Athlone, 
and will hail even the little gravel-ridges as welcome 
features in the plain. In the latter case he will pass the 
lordly range of the Galtees, and will have visions of the 
long chain of the Leinster granite between him and the 
eastern sea ; but his course will lie through a pleasant 
cultivated lowland, with white farms and foursquare 
mansions, and anon stretches of brown bogland, margined 
by wind-swept belts of firs. The structure of Ireland 
seems, then, fairly simple — a shallow basin, bordered for 
the most part by a rim of higher ground. 

The details of its structure have been put before 
geological readers in two well-known works ; and, in a 
more popular setting, by von Lasaulx,^ who visited the 
country in 1876. Gne of the most charming accounts of 
Ireland, and the most fully illustrated, is to be found 
in the work of another foreign author, M. Martel ; ; and 
the geological matter in this book is unfamiliar to most 
of us, dealing as it does with the underground water- 
ways of the Carboniferous Limestone area. In this and 
succeeding papers, I propose to regard Ireland from a 
broad standpoint, as a part of Europe, as a mass set 
upon the continental edge — that is, upon one of the most 
interesting structural lines of Europe at the present day. 

Bertrand and Suess, the authors of our more recent 
generalisations respecting European structure, have not 
overlooked Ireland as the visible western termination of 
their systems of earth-folding ; and the latter writer may 
be said to show an intimate acquaintance with the geology 
of the island. M. Bertrand; has recited to us the four 
principal epochs of mountain-making, and has somewhat 
daringly pictured the folds as successively extending south- 
ward, banked one against the other, from the Polar Circle to 
the Mediterranean. Certainly, the bared Arch:pan masses 
of the north, and the growing limb of the Italian region in 
the south,;; go far to support his generalisation. 

* Gr. U. Kinahan, " Manual of the G-eology of Ireland," 1878 ; and 
Prof. E. Hull, " Physical Geology and Geography of Ireland," Second 
Edition, 1891. " 

t "Aus Irland : Keisestizzen und Studien," Bonn, 1878. 

'X "Irlande et Cavernes anglaises," Paris, 1897. 

§ " Sur la Distribution geographiques des Roches eruptires en 
Europe." Jiull. Soc. giol. de France, Troisieme Serie, Tome XVI. 
(1887-8), p. 576. 

i; See Knowledge, Vol. XX. (1897), p. 2S5. 



Ireland, as an epitome, retains traces of these four great 
epochs. In the mountain-rim of the north and west, the 
oldest system of folds, the Ihironiaii chain of Bertrand, 
comes to light. Complex as the older rocks of Donegal 
may be, few will deny that their fundamental series is of 
equal antiquity to the Hebridean gneiss of Scotland ; while 
an interesting inland exposure in the east of the county of 
Tyrone shows that ribs of the pre-Cambrian chain are not 
far distant beneath any part of the north of Ireland. The 
handsome gneisses of this latter area, north of Pomeroy, 
form a broken moorland, to which echoes of the outer 
world travel slowly even in our own time — a region in 
which the old language, and the lirightness of the old 
costumes, linger almost witliin sound of the clanging ship- 
yards of Belfast. Flanking this core of antique rocks, come 
interpenetrating masses of igneous origin, and an extensive 
series of schists that form mountain-ridges of their own. 

In the counties of Mayo and Gal way, again, the strati- 
fied but metamorphosed series that underlies the first 
fossiliferous horizons is now known to be at least of 
Cambrian age ; and its general relationships would 
carry it down even further. The quartzite masses of 
the Twelve Bens of Connemara may even represent the 
Torridon series of Sutherland : and somewhere beneath 
them must lie the gnarled and twisted gneiss, forming 
part of the continent of " Huronian " times. South of 
this point the old rocks are cut off by the Atlantic, and 
play no further part in the structure of our modern 
Ireland. 

The ('al<-tl<mian epoch of mountain-building set in at the 
close of the Silurian period, and gave us the Grampian 
folds, and the great thrust-planes that have wrought such 
havoc with the true order of things in north-west Suther- 
land. f It gave strength and compactness to a great part 
of Wales ; and its first throes are seen in the break that 
occurs between the Ordovician and the Silurian beds in 
Shropshire. On the Welsh border, iu fact, the Caledonian 
movements made a start a whole geological period in 
advance of the main upheaval of the chains. 

Evidence of something of the kind is now reported from 
the west of Ireland; but the principal folding in that 
country certainly included Silurian beds as well as Ordo- 
vician. Along the east coast, from the neighbourhood of 
Belfast to the south of the county of Waterford, the 
Caledonian pressures have thrust up these two systems of 
beds on end, and have contorted or even inverted them. 
From the mountains and plateaux then raised, pebbles 
were copiously rolled down, to form the first deposits in 
Devonian lakes, or, later, in Carboniferous seas. In fact, 
a continent then arose across all the northern European 
area, on which room was found for the fresh-water basins 
of the Old Red Sandstone, and on the mobile edge of 
which the volcanoes of the Cheviots fumed. 

The surface of this continent is, then, exposed to us 
by denudation whenever the Devonian conglomerates are 
removed ; and certain portions of it must have stood up 
as barriers between the lake-basins, and were never sub- 
merged until the great subsidence, which readmitted the 
sea in early Carboniferous times. 

The great thickness of the Old Bed Sandstone implies 
that the floors of the lakes in which it was deposited, 
or of the estuaries that may have served in certain 
oases as the gathering-ground, were steadily sinking as 

* This, at least, may be safely concluded from the most recent 
results of the Geolog"ical Survey in that district. fAnn. Report 
GeoL Surrey of United Eini/dom. 1897, pp. 50 and 51.) 

t See the sections in the Survey. Report published in Quart. Joiirn. 
Geol. Soc, London, Vol. XLIV. (18SS\ p. 378. 



76 



KNOWLEDGE 



[Apeil 1, 1898. 



layer after layer was laid down. Between the parallel 
ranges of the "Caledonian" chain, long valleys of 
subsidence may have existed like that in which the East 
African lakes have arisen at the present day. By an 
opposite movement, along the planes of gradual faulting, 
the intervening ridges may have prolonged their existence, 
and may have maintained the level of the continent. By 




i^j^^^~ 



Fig. 1. — Sketch-map of Ireland, showing the direction of the 
principal axes of folding. The lines represent the trend of both 
anticlinal and synclinal axes. Lines with dots represent the 
" Caledonian " folding ; thick lines, the " llercynian " folding. 

our own times, a succession of later earth-movements has 
complicated the relations between the Devonian sandstones 
and the land-surface that gave them birth ; but we may 
still see in the great chain of Leinster one of the real 
highlands of "Caledonian" times. 

The marine Carboniferous beds abut directly on a great 
part of this chain, with no exposure of Old Eed Sandstone 
round their margins ; hence the ridge stood out as a long 
island even in the Carboniferous sea. To this day it 
forms the most continuous portion of the mountain-rim of 
Ireland, though shorn of its former schistose peaks by 
whole eras of denudation, and though the round back of 
the granite-core is now laid bare to view. 

The "Caledonian" uplift was characterised by a feature 
common in true mountain - chains — the intrusion of 
granite along the more important lines of elevation. As 
the long arch formed, the igneous mass rose with it, 
melting off its lower layers, sending ofif veins into higher 
ones, and inducing crystallisation and foliation in the 
argillaceous beds along the contact-zone. Hence the back- 
bone of Leinster became strengthened from below ; and its 
double structure is seen clearly in any traverse of the 
range. 

Bound Newry, again, granite forms a hard ridge inti- 
mately connected with the "Caledonian" folds; and at 
Castlewellan, a little further north, the igneous invader 
has been caught, as it were, in the act, and is seen to be 
stuck full of fragments of Ordovician or Silurian strata, 
which present every stage of alteration, from mere baking 
to almost complete absorption. It is very reasonable to 



suppose that the characters that distinguish the Newry 
granite from that of Leinster are induced by the amount of 
foreign material absorbed by it in the portion now exposed. 
Further evidence of the support given to the "Cale- 
donian " folds by the intrusion of granite is seen in the 
exposures in the county of Cavan. At and near Crossdoney, 
a granite of very various grain and character comes to the 
surface among the Ordovician shales. It is a miniature 
picture of the structure of the Leinster chain, and suggests 
the vast extent of similar features hidden throughout 
Ireland beneath the blanket of Carboniferous rocks. 

When we go north or west, we are confronted with the 
schistose ranges, which may be of any age between the 
date of the " Huronian " uplift and the Devonian period. 
Unconformities show that there were movements, unclassi- 
fied in the broad scheme of Bertrand, before Ordovician 
times; but the great folding of the country, like that of 
the Scotch Highlands, clearly occurred about the close 
of the Silurian period. To this we owe the green and 
romantic range of the Sperrins, a highland scarcely 
visited, even by the dwellers on its flanks ; also the 
whole present structure of wilder Donegal, with its 
ridges and valleys running north-east and south-west, still 
preserving the general trend of the Caledonian folds ; 
and, again, the superb coast-scenery of Slieve Liaga 
and Achil Island, where cliffs of two thousand feet 
remind us of the mass of " Caledonian " land that has 
become lost in the Atlantic. The uplift of Mweelrea, 
with its fossiliferous Wenlock zones, and of the Wenlock 
and Ludlow beds of the Dingle promontory, dates from 
the same period of unrest. In the latter spot one of the 
fractures reached the surface, and our unique volcano of 
Wenlock age threw its bombs briskly in the air, as a sign 
that the Silurian gulfs were about to pass into dry land, 

A great part, then, of the mountain-rim of Ireland is of 
extreme antiquity ; and in other places the pre-Devonian 
surface has been, as it were, restored to us after many 
strange vicissitudes. The Carboniferous subsidence con- 
verted the region of the British Isles into an archipelago ; 
and in Ireland the separate islands can sometimes be 
traced out by the conglomerates formed in the Carbon- 
iferous beds upon their flanks. This invasion of the sea 
left its mark upon the whole centre of the present Ireland, 
through the uniform deposition of the blue-grey Carbon- 
iferous Limestone. The denudation, and the actual solu- 
tion, of this rock have given us the landscapes of the 
great plain ; these become often impressive in their very 
breadth, and are never monotonous to those who love to 
watch the cloud-shadows move across the bogland or the 
lake, in a picture that takes half its life and colour from 
the changing temper of the sky. 

The great limestone-sea was thrust out, very gradually 
at first, by what is known in Europe as the Hercynian 
uplift, named after the forest-ranges of Central Germany. 
The sandy beaches that were formed as the sea shaDowed 
give us ledges of hard rock at the present day, such as that 
on the crest of C'uilcagh, where the Shannon first forms 
into a stream. The trend of the Hercynian folds was no 
doubt diverted locally by the surviving knots of the 
Caledonian chains ; but in many places the pre-Devonian 
land gave way. It was thus worked up again, and was 
brought into new prominence, and into a new scheme of 
arrangement, in the cores of the Hercynian folds." 

From the west of Kerry to Waterford, away on across 
Pembrokeshire and the South Welsh coalfield, under 
Oxfordshire and London, and through Belgium and Central 

* Compare W. J. Sollas, " Gteology of Dublin and its Neighbour- 
hood," Proc Geo!. Assoc, Tol. XIl'l. (1893), p. 113. 



Apbil 1, 1898,] 



KNOWLEDGE, 



81 



Cabrion Crows capturing a Lark. — A labourer told me 
he recently saw two Carrion Crows capture a Lark by 
seizing it on the wing. It was not a wounded bird, but in 
strong flight down some stubbles with many others. The 
Crows acted very cunningly, working together, one keeping 
above and the other below, with the Lark between them, 
and the upper repeatedly making swoops and at last 
seizing the Lark in its beak, when both Crows descended 
and commenced (not without a quarrel between themselves) 
to tear their quarry to pieces. — John Cobdeaux, Great 
Cotes House, R.S.O., Lincoln. 

Glaucous Gull (Laius gltiucus), — Mr. Geo. Adams, of 
Douglas, taxidermist, has shown me a Gull of this species 
recently received by him for preservation, and obtained on 
the island. It is an immature bird, in the whitish and 
pale brown plumage well described in Mr. Macpherson'a 
manual. This is, so far as I am aware, the second record 
of this Gull in the Isle of Man, though it has doubtless 
occurred much oftener. — P. Ralfe, Castletown, Isle of 
Man. 

Variation in the Song of the Mistle Thrush. — It seems 
to rne that the Mistle Thrushes near Eltham sing longer 
strains than are heard from those of Gloucestershire, and 
that the latter birds more frequently utter a few high 
broken notes after the strain, in the manner of a Blackbird. 
It would be interesting to leam whether anyone has heard 
the Mistle Thrush sing a long strain such as one hears 
from the Blackbird. This point appears to me important 
in connection with the fact that the young Blackbird, when 
commencing his fuU- toned song, utters short strains like a 
Mistle Thrush. — Charles A. Witchell. 

Song of the Redwing. — On the 6th of March I heard 
the song of a wild Redwing. The morning was very fine, 
and the bird sang earnestly. The strains were continuous, 
composed of a very rapid repetition of metallic but not 
loud notes, and lasted throughout the space of half a 
minute. Each strain contained a few short full-whistled 
notes. The whole song reminded one much of the 
twittering of a young Thrush in September, or the high 
sharp notes emitted by fighting Thrushes. I listened to 
the bird for some minutes. — Charles A. Witchell. 

Grei/ Phalarope near Kilk-enni/, Ireland (Irish yati<ralis/, March, 
1898, p. 88).— Mr. G. E. H. Barrett-Hamilton reports that a speci- 
men of this bird was shot by Mr. John O'Connell, jun., near Kilkenny, 
in October, 1897. 

Parus snlicarius (Brehm). — "A Hitheeto Oveelooked British 
Bird," by Ernst Hartert (Zoologist, March, 1S98, p. 116).— TTnder this 
title Mr. Hartert claims to add a new resident species to the British 
list. The bird in question is a Marsh Tit, called " Parus salicariiis," 
which is allied to the northern form, P. borealis. Mr. Hartert sars 
that P. salicariiis has been recently " re-discovered " and brought to 
his notice by two Continental ornithologists — Kleinsehmidt and 
Prazak. He himself has since then procured three specimens from 
Finchley. With no intention of shghting the authority of so well- 
known an ornithologist as Mr. Hartert, we feel disposed to await 
further evidence as regards the habits, the habitats, and the specific 
distinctness of this bird, before we venture to add it as a new species 
to the British list. 

All contribritions to the column, either in tJie way of notes 
or photographs, should be foncarded to Harry F. Withebby, 
at 1, Eliot Pluce, Blackheath, Kent. 

Note. — The first issue of Knowledge containing British Ornitho- 
logical Not^s was that for October, 1897. 

The British Museum has, we understand, acquired by 
purchase the valuable collection of fossil insects formed 
by the late Rev. P. B. Brodie, of Rowington Vicarage. 
The collection is the result of the labour of fifty years, and 
contains many historical and valuable specimens, including 
several types figured in various monographs and memoirs. 



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

VARIABLE STARS. 
To the F^ditors of Knowledge. 
Sirs, — A maximum of -j Ceti (Mira), following previous 
computed maxima, was due October Ist, 1897. The star 
rose in September at such late hours and under such 
unfavourable conditions of position, moonhght, and atmo- 
sphere, that, although it was looked for diligently, no satis- 
factory observations were obtained until the first week in 
October. Since then my observations are as follows : — 

Ma^. Mag". 



1S97. October 


8 
15 


5-8 
5-6 


1897. 


November 


25 

27 


3-4 
3-3 




17 


5-4 






30 


3-2 




18 


o2 




December 


4 


3-4 




19 


50 






5 


3-3 


,. 


23 


49 






12 


3-5 


„ 


24 


4-7 






22 


3-8 


„ 


27 


4-6 






2B 


3-9 


November 2 


4-2 






27 


3-8 


,, 


3 


41 






28 


41 




4 


40 






31 


4-5 




5 


37 


1898. 


Januarv 


1 


41 




6 


35 






6 


4-4 




7 


3-4 






7 


46 




11 


35 






16 


51 




12 


37 






22 


5-3 




14 


3-6 






26 


5-4 




17 


35 






27 


5-5 




18 


34 






28 


5-6 


„ 


21 


33 






29 


60 



There were many observations between these dates, but 
as no change of as much as a step 01 was seen, they are 
omitted. 

In the first week of October the star rose rapidly, and I 
am not unwilling to believe in a rise of a fuU magnitude 
on a single night. 

The maximum was reached on November 30th, which, 
after reviewing previous computed maxima, shows the star, 
Ceti, to have been sixty days late in 1H97. 

Comparison stars used were as formerly : 71, 6'55 ; 
75, 5-75 ; 70, 5-62 ; 66. 5-65 ; v, 5-2 ; f', 4-75 ; £-, 4-50; 
8, 4-2 ; a Piscium, 3-90 ; y Ceti, 3-5 magnitudes. 

The star was less than the sixth magnitude last night, 
changing slowly. 

Memphis, Tenn., U.S.A., DA\aD Flan'ery. 

12th February, 1898. 

To the Editors of Knowledge. 
SiRs.^At the last apparition this variable star has been 
brighter than at the two immediately preceding. There 
does not seem to have been much change in its magnitude 
between November 13th and December 3rd. From the 
observations given below I conclude that the maximum 
occurred between November loth and 23rd. 

Masr. Mag. 

5-2 1897. November 19th ... 3-3 

5-2 December 3rd . 3-4 

4-6 ' „ 12th ... 3-7 

3-8 „ 24th . 3-9 

3-4 „ 28th 4-1 
3-3 

Mira has not been seen since the last-mentioned date, 
owing to the almost continuous obscuration of the sky. 
Westminster, W. E. Beslet. 

February 14th, 189S. 

We regret that the Photograph of the Spectrum of Mira Ceti, 
appearing in the March Number, was printed without the guidelines, 
and with the reference numbers out of position. We propose to 
reproduce the photograph in our next issue.— Eds. 



1897. October 



20th 
21st 
29tli 
November 5th 
13th 
15th 



82 



KNOWLEDGE. 



[Apeil 1, 1898. 



BRITISH BEES.-II. 

By Fred. Enock, f.l.s., f.e.s., etc. 

IT is a well-known fact that many people are remem- 
bered by their "impressive manner"; so also are 
certain kinds of bees by their most impressive sting. 
The name Ccelioxys is quite suflRcient to recall to my 
mind the capture of my first specimen, which I saw 
flying very quietly past a prickly bramble, and then, being 
met somewhat unceremoniously by my net, it commenced 
to act on the defensive in a most vigorous way. Laying 
back its antennas and opening its mandibles, it twisted about 
its very sharply shaped abdomen in such an active manner 
that I found it an impossibility to avoid its long and 
powerful sting ; but I preferred the sting to injuring the 
delicate pubescence, which, if roughly handled, robs this 
bee of its beauty. Like the bloodthirsty " clegg " or grey 
gad-fly, this bee is almost silent in its flight. It is 
parasitic, and may frequently be caught hovering near the 
burrows of Megiicliile and Sampmhi. The males have a 
peculiar bifurcate appendage on the apical segment. I 
have often swept these bees up from meadows, and in days 
gone by it was possible to obtain specimens of C^. simplex at 
Hampstead ; but those days, like the sandbanks there, have 
passed away. 

Of the next genus, Stdia, I have had no personal 
experience, though frequently directed to its quarters by 
the late Fred. Smith, who adx-ised me to collect all the 
pierced bramble stems I came across. 

The genus Melecta contains but two species, both most 
beautifully marked, the abdomen of M. luctuosu being 



ikA^ 




^^^^[ jffT/^ 


} 


^^n(^UrT^%k A 


1^ 




^« , 



Fig. 1. — Rose Leaves cut by Megachile. 

adorned on each side with tufts of silvery white hairs on a 
shining black ground. The flight of this bee is slow and 
gentle, and so far as my experience goes, it seldom wanders 
far from the burrows of Aiithophorn, in whose cells it is 
parasitic. Last year I was delighted to find that a small 
colony had not been quite turned out from Hampstead 
Heath, though more than half the bank had been cut 
through for " improvements." M. Iwtuosa was then 
enjoying a sluggish flight in the bright sunshine, and, 



quietly alighting on the sandy ground close to an Antho- 
phora's burrow, sat pluming itself, patiently waiting for its 
mate. It is very easy to capture when so basking, but 
painful and powerful and far-reaching is its sting. 

The bees forming the genus (Jsmin exhibit an immense 
amount of intelligence in the selection of situations for 
their burrows. Some of these are made in sandy banks 
or in the decaying trunk of an old willow tree, and in such 
situations the boring of a deep hole is comparatively an 

easy matter to these 
busy insects, which 
are such patterns of 
industry. A short 
time ago a brother 
entom ologist showed 
to me a number of 
cells which some bee 
had made in the 
space between two 
section boxes in a 
hive. These I 
quickly recognized 
as those of an (ismia. 
Many times have I 
watched ( >smia rufa 
gomg in and out at 
a small bolt-hole in 
one of the tombs at Highgate Cemetery. No doubt this 
had become the family mansion of these beautiful bees, 
which have a great love of locality. 

We now pass on to the genus Meffarhile, the leaf-cutting 
bees, which are without doubt the most intelligent insects. 
All the species (some nine in number) cut pieces from 
various kinds of leaves, with which they build their cells in 
burrows formed in sandbanks, old decaying trees, as well 
as in the crumbling mortar of old walls, and under old tiles. 
Several species are quite common in London gardens 
during June and July. There is a considerable amount of 
businesslike bustle about them, which is most attractive 
to the naturalist, who is quite willing to allow them to cut 




Fig. 2.— The Leaf-cutter Bee. 




Fig. 3. — Under Side and Side View of Abdomen, showing 
PoUen-polIeeting Hairs. 

up the leaves of his rose bushes so that he may have the 
opportunity of studying their habits. Though certain 
species prefer the green leaves of the rose (Fig. 1), they do 
not hesitate to cut circles and oblongs from almost any good 
sound leaf. I have watched them attack those of laburnum, 
rhododendron, laurel, sweet pea, nasturtium, geranium, 
laurustinus, etc., etc. Two years ago I saw M. centun- 
cuhnis cut dozens of pieces from the soft leaves of an 
edible pea in a London garden which did not possess a 



April 1, 1898.] 



KNOWLEDGE, 



83 




Fio. 4.— Heiid of Loaf. cutter Be 
Mandibles ready for cutting. 



rose bush. These bees are remarkable for their strength 
of flight and mtiscular mandibles, legs, and stings, while in 
general build they are much heavier than the honey bee. 

(Fig. 2.) The pollen- 
gathering hairs are 
spiral in shape, 
arranged in rows on 
the under side of the 
abdomen (Fig. 3), 
and are of a chestnut 
colour. The males 
of iV. WUluijhhiAh, 
are very beautifully 
clothed with hairs of 
wonderful form. 
This is especially 
noticeable in the 
tarsal joints of the 
anterior legs, which 
have long fringes 
of curled hairs. 
These hairs are 
spread wide open and the legs kept forward when the 
bee is on the wing following in the wake of the female. 
I'pon her he waits in the most attentive manner, flying 
after her wherever she goes, though sometimes his atten- 
tions do not appear to be altogether appreciated. As 
soon as the courting and nuptials are over, the female goes 
in search of a suitable sandbank in which to drive her 
tunnel. This she makes about half an inch in diameter, 

and excavates to a 
depth of eight or 
nine Inches in a 
horizontal direction 
(Fig. 6). The sand 
is at first removed 
with her powerful 
jaws (Figs. 4 and 5), 
but as she goes 
deeper and deeper 
the legs are used for 
cleaning it away by 
scratching and 
shooting it out at 
the entrance. When 
the required depth 
has been reached, 
and the burrow 
cleared and swept 
of all loose sand, the bee carefully lines it with a 
delicate membrane laid on in a fluid state from its 
mouth. When this operation is finished, the burrow 




Fig. 



-Head of Leaf-cutte 
showing Ch'peus. 




Fig. 6. — Tunnel of the Leaf-cutter Bee, driven into a 
Sandbank. 

is ready for the reception of the building materials 
forming the cells. In the case of WilluffhbieUa these 
are made entirely of pieces of green rose leaves, taken 




Fit 



-Third Pair of Le 



preferably from a Marechal Niel. The building up of 
these cells, were they constructed by human hands, would 
no doubt be looked upon as a wonderful performance ; but 
where could be found a workman clever enough to attempt 
such a task, even supposing he were allowed to make the 
habitation on a much larger scale '? Let us examine the 
structure in detail. We find a hole ten inches deep 
and half an inch in 
diameter, containing 
from nine to a dozen 
cylindrical cells fit- 
ting one on top of each 
other somewhat like 
a pile of thimbles. 
They are all of one 
size, and are com- 
posed of pieces of 
leaves, cut to certain 
shapes, each piece 
being accurately fitted 
and placed in order in 
its right position. 

It is only after years 
and years of the most 
careful observations, 
aided by a number of 
small contrivances for 
watching these creatures at work, that we are able to give 
every detail as we have seen it. But such observations 
are not to be completed in one season. The links com- 
posing the life-history of any common insect often remain 
hidden, and evade the most untiring search for years, or 
the greater part of one's life. Some writers state that this 
bee, after cutting ten or twelve pieces of leaves, "enters 
the tunnel, and begins to twist and fold the leaves, making 
them fit together into a sort of funnel-shaped cone, 
something like a 
thimble." A human 
being does occasion- 
ally do things in a 
rough, jumbling 
fashion, but a leaf- 
cutter bee, never ! I 
speak positively on 
this subject, as I have 
watched the bee make 
its burrow and then 
commence its cell, 
besides having fre- 
quently unearthed 
burrows containing 
cells in all stages. 

Now let us go back 
to plain facts, leaving 
theories for " the 
armchair naturalist." 
The tools with which this wonderful leaf-cutter bee cuts 
out most accurate circular pieces of leaves are her two 
powerful jaws (Figs. 4 and 5). These are beautifully 
chiselled out, so that the exceedingly hard edges of the 
teeth are perfectly sharp, working one over the other like 
a pair of gardener's shears. Another valuable and in- 
dispensable set of tools is to be found in the six legs, 
each one containing several brushes and combs of the 
finest quality and each one adapted for a certain purpose, 
while the whole set of legs form a perfect vice (Figs. 7 
and 8), in which the leaf to be cut is held in a firm 
grasp, and in such a position that the jaws and head 
can work round freely — so freely, indeed, that in less than 




Fig. 8.— Third Pair of Legs, siuf. 



84 



KNOWLEDGE. 



[Apeil 1, 1898. 



twenty seconds the bee has cut out an exactly circular 
piece of leaf, just the size for her purpose. 

To watch these bees at work on a bright sunshiny 




FiO. 9. — Leaf-cutter Bee cutting circular piece from leaf. 

morning (and they get up and to work very early) is to 
me one of the most fascinating sights. Two years ago I 
spent several days in succession watching M. cetitunatlaris 
cut dozens of pieces from a soft-leaved sweet pea growing 
up my summer arbour, which backed against a wall eleven 
feet high (not too countrified). My busy visitor arrived 
on June 14th, pitched down upon a leaf, and before I could 




Fig. 10. — Leaf -cutter Bee flying away with circular piece. 

take out my pencil and note-book it had flown over the 
wall, carrying with it a piece of the leaf. I quickly 
obtained my field-glasses, and returned to find that during 
my absence the bee had again visited the pea, and departed 
with another piece of leaf. I had not long to wait for its 
return, and now, being armed with note-book, I settled 
down to steady work. The bee pitched upon the top edge 
of a leaf, with its head towards the base (Fig. 9), and, 
placing three legs on one side and three on the other, it 
took hold of the edge with its jaws. Then the jaws began 



opening and closing rapidly, and the head was moved down 
and round. So quickly were these operations performed 
that in just fifteen seconds the bee had cut a circular piece 
from out of the leaf (Fig. 10). The insect then dropped 
down slightly, but recovered itself, and flew up towards the 
wall. I watched it with my glasses, and saw it fly over the 
wall to an old outhouse covered with tiles, under one of 
which it quickly disappeared. In less than a minute it 
reappeared, and flew straight for my boundary wall and 
down on to the pea. Taking hold of the lower edge of the 
leaf from which it had cut the circular piece, it commenced 




Fig. 11. — Leaf-cutter Bee, cutting ao oblong piece from leaf. 

operations this time by making a much larger arc ( Fig. 11), 
which was finished off just before the midrib of the leaf 
was reached. The bee then continued to cut almost 
parallel to the midrib for a distance of over half an inch, 
and then, turning, it completed its task in the form of a 
segment of a circle. Once more it dropped towards the 
ground, and, recovering as before, flew off over the wall 
to the tiled outhouse. It laboured thus for between three 
and four hours, during which time I noted down the 
following particulars. Fifteen seconds were occupied in 
cutting out a circular and twenty-seven seconds an oblong 
piece of leaf. The journey to and from the tiles, including 
arranging the piece of leaf, was performed in less than 
one minute. When the leaf was almost cut through the 
bee poised itself by gently vibrating its wings, and so 
prevented the weight of its body from tearing the leaf. 
Day after day the industrious bee visited my garden, until 
there was scarcely a perfect leaf left on the clump of sweet 
peas. From 1870 to 1874, each June, I observed numbers 
of Megachile centuncularis visiting a clump of everlasting 
peas, the flowers of which they are exceedingly fond of, but 
I did not observe that they cut the leaves. They are 
particularly fond of the leaves of the garden fuchsia. 
(To be continued.) 



IN 



THE MOON'S NORTHERN REGIONS. 

By Arthur Mee, f.r.a.s. 



ALTHOUGH the northern regions of the moon 
cannot compare for one moment with the glorious 
and bewildering complexity of the southern, still 
they contain a number of interesting objects that 
never fail to delight the observer. Take, for in- 
stance, the fine picture which illustrates these notes. It 




NORTH. 
THE LUNAR ALPS AND THEIR NEIGHBOURHOOD. 



April 1, 1898.] 



KNOWLEDGE, 



85 



is a reproduction of plate No. 6 in the Observatory Atlas of 
the Moon in course of publication by the Mount Hamilton 
Observatory, the original negative of which was secured 
April 9th, 1897 ; moon's age, eight days. 

The reader will hardly need to be reminded, ere we 
proceed with our brief description, that the Lick and Paris 
Observatories are each publishing atlases in which the 
original photogpraphs taken at the respective institutions 
are moderately enlarged. A third publication is that of 
Prof. Dr. Weinek, in which the magnification is pushed 
a good deal farther in the able hands of this most 
skilful selenographer. Last comes the atlas of Herr 
Krieger, who has deftly inserted details at the telescope, 
using existing photographs as a guide. A comparison of 
these various methods and results is deeply interesting and 
instructive, and these atlases between them must immensely 
advance our knowledge of the moon. 

The scale of the accompanying photograph is not large 
enough to bring out those minutiie which have such interest 
for selenographers, and which at times give rise to lively 
and even acrimonious discussion. But though detail be 
wanting, the picture shows — very nearly as well as though 
the reader were actually peering through the eyepiece — the 
broad lines of lunar landscape, which are perhaps as 
important in the framing of hypotheses as the minute 
objects amongst which the wielder of high powers is always 
so happy to revel. 

Our key-chart will render easy the identification of the 
various objects in the photograph. The sun is just rising 





0/ 


- 




'' r. 


1 / 




M7 


^ 




/r O 


o 




^ , o 






O 






^9 CS- 


05^ 


<^ 






^(^r^~\,.=^ 


X / 

r^ ' 




Mare Frigoris 


'■"•J 




^. ^ ~^rtA,™. 




"\ 




Bona '^-^ 




^^^^^^-^^-^ 


JC 






' " 



on the western ramparts of Plato, and is throwing the 
Alps, Caucasus, and Apennines into splendid relief, all the 
more marked because of the sombre plain from which they 
rear their crests. Let us look for an instant at the great 
craters which the photograph includes. 

The largest is Aristoteles, and somewhat to the south 



the smaller but still immense Eudoxus. Aristoteles is no 
less than sixty miles in diameter, and its walls rise to a 
maximum height of eleven thousand feet above the floor. 
It is, however, but imperfectly seen in the illustration, for 
the camera cannot be prevailed on to show objects exactly 
as they appear to the eye, introducing a glare here and a 
blackness there which detract somewhat from its inestim- 
able value. 

The splendid ring of Archimedes is described by Elger 
as " next to Plato the finest object on the Mare Imbrinm." 
It is fifty miles in diameter, but the walls are less lofty 
than those of Aristoteles. Still, the shadows show out 
splendidly as sunrise progresses, whilst about the lunar 
noon a curious system of craterlets and light streaks is 
revealed, reminding one of the interior of Plato. 

To the north-west of Archimedes lie Autolycus and 
Aristillus • — stately names aU three ! Both the latter 
are the centres of minor ray systems, and Aristillus is 
" flanked on all sides " (as Webb tells us) " by radiating 
banks resembling lava streams, or currents of ejected 
blocks or scorin}," of which there is just a faint trace in 
the illustration. On its eastern side Aristillus is eleven 
thousand feet deep. 

To the north, between the Alps and Caucasus, is the 
interesting crater plain Cassini, which will afiford the lunar 
draughtsman many hours of pleasant work ; and he may 
afterwards compare advantageously his drawings with the 
photographs in Knowi,ei>(;e and elsewhere. 

Towards the north pole of the moon we have quite a 
crowd of craters, confused by foresbortenin;,', but forming 
a very poor second to the tremendous display near the 
southern extremity of the axis. 

Most of these objects have but feeble terrestrial analo- 
gies, but when we turn to the lunar mountain ranges we 
seem on more familiar ground. And what a glorious 
spectacle would stretch before the observer could he but 
stand on one of these lofty peaks — on Mont Blanc (twelve 
thousand feet). Mount Wolf (eighteen thousand feet), or 
Caucasus (nineteen thousand feet) ! What a bewildering 
panorama would it not be — a " nightmare vision," as one 
writer calls it, only to be imagined in our dreams ! 

Perhaps the great mountain ranges are the most satis- 
factorily depicted of any objects on the photograph before 
us. They will bear long looking at, but must of course be 
seen in the telescope to appreciate their full magnificence. 

The eye will not be long before it rests on that very re- 
markable object, the great valley of the Alps. This mighty 
gash, as though the work of some gigantic axe, is above 
eighty miles long, and to be distinctly seen in all but the 
feeblest telescopes. Only from four to six miles broad, its 
walls tower up for well-nigh twelve thousand feet. At its 
southern end it opens out into a noble amphitheatre. Webb, 
Elger, and others have studied and drawn this wonderful 
valley, and two of Mr. Elger's drawings enrich the Jouninl 
of the Lirt-r/iool Astinwrnical Societi/. The lunar members 
of the British Astronomical and other Associations might 
well turn to the great Alpine valley as a change from the 
bewildering spots, craterlets, and streaks of more frequently 
delineated objects. 

^- 

Notftgg of ISooitg. 

A Treatise on Chemistry. By Sir Henry Koscoe and 
C. Schorlemmer, f.r.s. Vol. II. — " The Metals." (Mac- 
mUlan.) Illustrated. 31s. 6d. Nineteen years have now 
elapsed since the publication of the first edition of this 
treatise, and in consequence of the many innovations in 
the chemistry of the metals during that period, the 
present edition (the third) may be regarded as a new 



86 



KNOWLEDGE. 



[ApBn, 1, 1898. 



work. Drs. Colman and Harden have taken part in the 
sweeping changes which have been necessary to bring the 
work into harmony with the present condition of chemical 
science, the systematic description of the metallic elements 
and their derivatives having been re-arranged in accord- 
ance with Mendeleeff's — the Eussian chemist — natural 
classification, which resolves the elements into eight 
groups, the members of each group showing in most 
cases a close connection with each other. By thus taking 
advantage of the hint aiibrded by the natural gamut of 
the elements, so to speak, the study of chemistry becomes, 
in a way, comparable to the study of botany or zoology, 
the eight groups of elements being the equivalents of the 
chief representatives of the great groups of plants and 
animals, while the individual members of each group may 
be likened to the different species — all bearing certain 
characters in common, but with specific differences. Such 
a relation between the organic and inorganic is not incon- 
sistent with the unity which science has shown to exist in 
the universe, and the sooner this method of conveying a 
knowledge of the chemical elements becomes general the 
better it will be for all concerned. Chemistry, however, 
has in recent years grown to such gigantic proportions 
in both its main branches, organic and inorganic, 
as well as in its theoretical and practical aspects, 
that a book, in order to be of maximum value to 
a student, must be consistent throughout. If it is a 
book purporting to deal with the principles of the science 
it must steer clear of the technical or industrial applica- 
tions, otherwise there is sure to be a too apparent deficiency 
somewhere. Special treatises are required, and exist, 
nowadays, for such purposes as soap and alkali making, 
the metallurgy of iron, copper, etc., and the extraction of 
gold and silver from their ores. In the article on gold 
mining, for example, in this work much space is occupied 
on such subjects as the capital and labour required in the 
working of auriferous deposits, which are certainly outside 
the domain of theory, and yet not full enough to be of 
practical value to the actual miner. The same remarks 
would apply in the case of the section on iron smelting 
and the Bessemer steel process, as well as several other 
chapters, such as the manufacture of glass, bleaching 
powder, and so on. A proper division of labour in matters 
literary as well as industrial has its advantages. In the 
case under consideration, had the authors confined them- 
selves to the pure principles of chemistry, and reserved 
the technical portions for books professedly practical, the 
book need not have swollen to its present dimensions, and 
might then, at a lower figure, have been accessible to 
students in general ; whereas it is now almost entirely con- 
fined to libraries, where it can only be casually consulted, 
and its many excellencies are thus buried as far as the 
great majority of chemical students are concerned. 

Nates on Carpentry and .Joiner ij. By Thomas Jay Evans. 
Elementary Course. (Chapman ct Hall.) Illustrated. 
7s. 6d. Students preparing for the technical examinations 
of the City and GuOds of London Institute, the Technical 
Education Board of the London County Council, and 
other examining bodies, will find here a reliable guide. 
The subjects included are practical geometry, graphic 
arithmetic and statics, elementary carpentry and joinery, 
and mensuration — a course of instruction well adapted for 
apprentices who desire to acquire a thorough knowledge 
of the principles underlying their craft. The text is lucid, 
the diagrams large and well drawn, and, where necessary, 
in the geometrical portion of the book, practical methods of 
solving problems are given such as the workman would be 
required to use in the shop. The section dealing with 
graphic statics and mechanical contrivances is particularly 



good. Drawing, of course, takes the place of calculation 
in this section, and Mr. Evans has, we think, succeeded in 
presenting an intelligible exposition of the principles 
involved in this useful method of computing strains and 
stresses. Isometric projection, in both its theoretical and 
practical aspects, comes in here for a fuller and more 
luminous treatment than we have ever seen before in a 
book of this kind ; and, considering its value in practice, we 
are of opinion that the author has acted wisely in making 
this departure, although it has been somewhat at the 
expense of other important sections — the resolution of 
forces for example, the treatment of which is rather meagre, 
and yet the subject is one difficult to comprehend, espe- 
cially by students whose groundwork in mathematics is 
circumscribed — a condition of things which nearly always 
obtains among the artizan classes. On the whole, how- 
ever, we have nothing but praise for Mr. Evans's work. 
He has so subordinated and dovetailed the subjects 
forming the groundwork of an artizan's education that we 
venture to think there is no better book available for such 
a purpose. 

Glimpses into Plant Life. By Mrs. Brightwen, f.e.s. 
(Fisher Unwin.) Illustrated. Mrs. Brightwen is well 
known for her writings for young people, and this book is 
executed in her usual clear and pleasant style. It is written 
with the intention of preparing the " minds of young 
people for the study of botany by explaining in the simplest 
language some of the elementary phenomena of plant 
life." For this purpose we are sure it will be successful. 
Some of the many subjects dealt with are roots, tree 
stems, leaves, flowers, fertilization, fruit, and habit of 
growth in plants. The illustrations are good and adequate, 
and a useful glossary of scientific terms is provided. We 
have no hesitation in heartily recommending the book to 
young botanists, or, indeed, would-be botanists of any age. 

The Eh'itients of Hypnotism. By Ralph Harry Vincent. 
Second Edition. (Kegan Paul.) 5s. If the amount of 
literature published on a subject is a measure of its worth, 
then hypnotism is insinuating itself more and more into 
popular favour in spite of the ignominy heaped upon it by 
the practices of the professional entertainer, the charlatan, 
the juggler, and the trickster, who have laid their hands 
on the much-suffering science, for the number of books 
on the subject is now not only large but also rapidly 
increasing. The public, which in the main is entirely 
ignorant of the nature of hypnotism, has always regarded 
the subject as something akin to the supernatural, and 
quacks have made their fortunes by availing themselves of 
this weakness and mesmerising human beings in the 
presence of large assembUes ; hence, mesmerism has long 
been a sort of byword for all that is low and contemptible. 
Hypnotism has also antiquity to recommend it — if age be 
a virtue in matters intellectual — for it dates back as far as 
the year 15.52 b.c, when it was practised in Egypt. The 
early kings of France were credited with curing people by 
the " royal touch "; and even in Queen Anne's time faith in 
this mode of cure was still in vogue. Aa to the ultimate 
value of hypnotic science it is difficult, at this stage, 
to form any clear notion ; but Mr. Vincent has certainly 
made the subject attractive, and, by numerous footnotes of 
reference to literature of this kind, has invested his work 
with a fund of information which will be specially accept- 
able to those who wish to pursue their studies further than 
is possible by the aid of a single volume. A chapter 
on the use of hypnotism in detecting crime, and the 
medical treatment of patients by mesmerism, concludes the 
book — a chapter, by the way, which we think might with 
advantage be amplified in a subsequent edition. Some 
noteworthy remarks are advanced on the way in which 



Apbil 1, 1898.] 



KNOWLEDGE 



87 



hypnotism has been abused and misrepresented in modern 
fictiou, and it is certainly remarkable that all such writers 
should have failed to convey " any true idea of the 
hypnotic state or the dangers which may attend its use." 

Aivln'f and hi.H lialloon. By Henri Lachambre and 
Alexis Machuron. (Constable.) Illustrated. Os. There 
is little of importance in this book that was not generally 
known before its publication. In the introduction a very 
brief history of the life of Andrt'e is followed by a detailed 
account of the construction of the famous balloon. The 
rest of the book deals at great length, and in a highly 
emotional style, with the two expeditions to Spitzbergen, 
and the work done there in connection with the inflation 
of the balloon, to which is added an account of its final 
departure with the three explorers on July 11th, 1897. 
As everyone knows, the first of these expeditions was a 
failure. Owing to the prevalence of northerly winds the 
balloon was unable to start, and the whole expedition had 
to return. M. Lachambre accompanied this expedition to 
superintend the inflation and general preparation of the 
balloon. M. Machuron accompanied the second and suc- 
cessful expedition in the same capacity as his collaborator. 
The whole story would have formed a fitting subject for a 
couple of magazine articles, but there is nothing in it to 
warrant its publication in book form. 

The Xaturalixt's Directory, L'^ft.'i. (Upcott Gill.) Is. 
The idea of this book is good, and if it were conscientiously 
and exhaustively carried out the work would have con- 
siderable value. As it is, the inconsistent omission of the 
names of a number of well-known naturalists makes the 
book utterly worthless. This is now the fourth year of its 
publication, and we almost cease to hope that it will ever 
have any value. Perhaps the editor, whose name is not 
disclosed, will some day be aroused by his critics and wake 
up to his responsibilities. 

The Jdiinuih of Walter White. With a Preface by his 
Brother, William White. (Chapman \ Hall.) Gs. Walter 
White was for thirty years the assistant secretary of the 
Royal Society, having been appointed to that office after 
serving ten years as sub-librarian. In his later capacity 
he came into intimate contact with many of the men 
whose names are now famous throughout the world. The 
diary, which he seems to have very carefully kept, con- 
tains all sorts of interesting facts — many of them trivial, 
it is true — about notables, as well as quaint expressions of 
his views of things in general. Some of his reflections on 
the characters of various men of science might, we think, 
have been rather more carefully edited. Men of science, 
like other mortals, are not without their faults and eccen- 
tricities, but no good purpose is served by exhibiting them 
to the public. We did not anticipate finding that Prof. 
Dewar, when he was younger than he is now, remarked to 
the diarist that " he was shocked when in London by the 
self-seeking of scientific men ; no man caring to work for 
love of the work." Much water has, however, passed 
under the bridges since then. If any of our readers find 
themselves with an hour which they can spare, they will 
be able to pleasantly occupy it with these journals of 
Walter White. 

The Knciiclo}ixdi(i of Sport. Edited by the Earl of 
Suffolk and Berkshire, Hedley Peek, and F. G. Aflalo. 
Vol. I. (Laurence i Bullen.) Illustrated. This work, 
which iy to be completed in two volumes (the first of which 
is now under review), is being issued in parts. There is 
no doubt that such a work is needed, since it will take the 
place of " Blaine's Encyclopwdia of Kural Sports," which 
is now quite out of date. The scope of the present volume 
is very wide and embraces every sort of sport, from 
amateur athletics to leopard spearing, besides describing a 



great many beasts, birds, and fishes, and dealing with such 
a subject even as "first aid." The articles are for the 
most part written by authorities on the several subjects 
treated of, and the matter is therefore generally accurate 
and up to date. A bibliography is provided at the end of 
each important subject, and this forms a very valuable 
adjunct. Mr. Millais' statement, on page 118, that blaek- 
game are practically extinct in the New Forest is not 
warranted by the fact. There are still a fair number of 
blackgame in the New Forest, as, indeed, the Marquis of 
Granby correctly states on page 487, in the article on 
grouse. In dealing with the use of brass cases for wild- 
fowl guns {page 49ii), some mention should have been 
made of the pegamoid waterproof cases. The book is 
provided with a large number of illustrations, many of 
them very fine. Amongst these are a number of drawings 
by Mr. Thorbum, whose only weak point seems to be a 
lack of accurate proportion. We would draw attention 
to the picture of the capercailzie, facing page 178. The 
male and female birds are here made about the same 
size, notwithstanding the very marked difference in size 
of the two sexes. If the second volume proves equal in 
accuracy and completeness to the first, this encyclopaedia 
will form an indispensable book of reference to sportsmen 
of every order. 

Applied Mechanics. By John Perry, ii.e., d sc, f.r.s. 
(Cassell & Co.) 93. It is not too much to say that the 
publication of this book was awaited with the greatest 
interest by all teachers of applied mechanics in those 
technical schools and science classes where the subject is 
taught under the regulations of the Science and Art 
Department. Prof. Perry was quite recently appointed 
the examiner in applied mechanics for the central authority 
at South Kensington ; consequently, there are upwards of 
eight thousand students, in nearly three hundred classes, 
interested in learning how he thinks this subject should be 
taught and learnt. At the outset we venture to say that, 
under the conditions which obtain in the ordinary evening 
classes, applied mechanics cannot be taught in the way 
Prof. Perry lays down as the only proper method. The 
first chapter opens with the statement : " The student of 
applied mechanics is supposed to have some acquaintance 
already with the principles of mechanics ; to be able to 
multiply and divide numbers, and to use logarithms ; to 
have done a little practical geometry ; to know a little 
algebra, and the definitions of sine, cosine, and tangent of 
an angle ; and to have used squared paper. He is supposed 
to be working many numerical and graphical exercises ; to 
be spending four hours a week at least in a mechanical 
laboratory ; to be learning about materials and tools in an 
iron and wood workshop ; and to be getting acquainted with 
gearing and engineering apphances in a drawing office and 
elsewhere." This reads well enough, but we wonder how 
many of the students who present themselves for instruc- 
tion at the first meeting of an elementary class in applied 
mechanics in connection with the Department of Science 
and Art are able to do half the things enumerated in the 
paragraph we have quoted ? The book will have been a 
disappointment to the teacher who has to be examined by 
its author, for it is evidently addressed to a different class 
of student altogether. Of the volume as a treatise on applied 
mechanics it is unnecessary to say anything. Prof. Perry's 
name is evidence enough that the book is accurate, modem, 
clear, and practical. It is svritten in a style which imme- 
diately arrests the reader, but soon makes him angry with 
the frequency of the outbursts against " academic " 
methods, and the free use of the first person singular. 
Certainly every teacher of the subject should read the book 
from cover to cover, and then, if possible, re-read it. 



88 



KNOWLEDGE 



[Apbil 1, 1898, 



Some Unri'coiinized Laus of Xalure. By Ig^natius Singer 
and Lewis H. Berins. Illustrated. (John Murray.) 18s. 
There are a few pages in this book worth reading ; the 
remainder produces vexation of spirit. To criticize the 
book in detail would take up far more space than we can 
spare, and though it is the duty of a scientific periodical 
to prick the bubbles of paradoxers, life is too short to 
explain fully why their destruction is desirable. The best 
way to deal with a work of this kind is perhaps to leave it 
alone, when it will die of inanition. We will, however, 
state briefly some of the reasons why this book is unworthy 
of the attention of students engaged in the realities of 
science, selecting our instances from many marked in 
the course of reading the book. " The current assump- 
tion is of two kinds of electricities ; but though the two- 
fluid theory has its rival in what is called the single-fluid 
theory, it is still the dominant conception." This state- 
ment is not correct ; the two-fluid theory of electricity is 
as dead as Queen Anne, so far as scientific men are 
concerned, yet the authors spend page upon page in 
killing it. They do not seem to be at all familiar with 
modern conceptions of electrical phenomena. Bodies 
weigh less at the Equator than in Polar regions, the 
reason being that they are further from the centre of 
mass, and that there is a greater tendency for them to be 
thrown ofi", on account of the earth's rotational velocity. 
The authors endeavour to show that the argument 
derived from considerations of the earth's mass is not 
admissible, but they entii-ely neglect to consider the 
levity given to bodies at the Equator in consequence of the 
earth's rotation. They make erroneous statements as to 
the periods of vibrations of pendulums, and their theory 
of the cause of the earth's axial motion is ludicrous. 
They hold that "no contradiction is involved in as- 
suming the axis of the earth to be at right angles to 
its circumsolar path ; and that the obliquity of the 
ecliptic can be explained by the 'up and down' motions 
of the earth on its axis." Sunspots are believed to be 
" planets but a comparatively short distance from the sun, 
and revolving round it," which absurd theory is enough 
to put any observer of solar phenomena completely ont of 
patience. We need not give any further instances of the 
kind of mistaken ideas with which the volume bristles. 
No volume that has come before us during the last two 
or three years more fully justifies the expression that 
" what is new in it is not true, and what is true ia not 
new." 

Elrments of the ('oinpardtive Anatomy of Vertehrates, 
Adapted from the German of Dr. Kobert Wiedersheim by 
Dr. W. N. Parker. (Macmillan.) This second edition of 
Prof. Parker's work is based upon the third edition of Dr. 
Wiedersheim's standard treatise. Faithful translation of a 
German scientific work is always diftioult and generally 
undesirable. A much better method is to use the original 
freely, and to aim at presenting ideas accurately, rather 
than slavishly following the text. This is the principle 
which Prof. Parker, with Dr. Wiedersheim's permission, has 
adopted. As a result we have a book in readable English, 
and admirably adapted for English students of comparative 
anatomy. Considerable condensation of the third German 
edition has taken place in some sections, but new material 
has been added to others. Prof. Parker's object has been 
to prepare a short textbook, which, while retaining the 
original descriptions and arrangement as far as possible, 
should deal with the more essential and well -ascertained 
facts of comparative anatomy. He has carried out his plan 
most successfully, and the only criticism we have to offer 
is that the treatment is a little unequal, the skeleton being 
dealt with much more fully than some of the other organ- 



Probably Prof. Parker has his reasons for 
this, though it will not find favour with all students of 
morphology. The organ-systems described in order in the 
book are as follows : (1) the outer covering of the body, or 
integument ; (2) the skeleton ; (3) the muscles, together 
with electric organs ; (4) the nervous system and sense 
organs ; (5) the organs of nutrition, respiration, circulation, 
excretion, and reproduction. By dealing with the facts in 
this way the student is led to see clearly that there has been 
an evolution of organs as well as of animals, and this ia 
the right aim of the study of comparative anatomy. The 
remarkably fine illustrations — there are three hundred and 
thirty-three in all — assist the text in showing the various 
phases of development of the organs of vertebrates. A 
valuable bibliogpraphy concludes this excellent work, which 
will be of great service to medical students as well as to 
students of comparative anatomy. 



SHOET NOTICES. 

A First Year's Course of Experimental Work in Chemistry. By 
Ernest H. Cook, D.8C. (Arnold.) Illustrated. l8. 6d. ])r. Cook's 
book contains the usual instructions for conducting an elementary 
class in practical chemistry. The experiments are well chosen for 
emphasizing fundamental principles, but the illustrations are rather 
sparsely distributed. " Very brief accounts are given in the text," in 
order to judge the better of the student's honesty and care in 
<ibsr'rvation. Indeed, brevity is here carried to such an extreme, one 
may safely predict that the student will do little work by following 
the text unless the teacher is always at his elbow. 

Organic Chemical Manipulation. By J. T. Hewitt, D.8C. (Whit- 
taker.) Illustrated. 7s. 6d. Books on practical organic chemistry 
are comparatively rare, and there is room for a good, handy, and 
cheap treatise on the subject. Dr. Hewitt has, in a measure, met 
this deficiency, but he has spoiled his chance by a prohibitive price — 
a price out of all proportion with the dimensions of the book and 
the cost of first production. Accurately and concisely written, the 
work is of more than ordinary value to students of organic chemistry. 
A large section is devoted to quantitative analysis, which the author 
lorrectly states in the preface has not heretofore been treated as fully 
as it ought to be. A goodly number of preparations is given, including 
the fatty and aromatic series, together with a number of rare com- 
pounds, and the synthesis of organic substances — a new feature in 
books of this class. Besides the mere preparation of the compounds 
suitable explanations are advanced of the theory of the reactions 
which take place ; and, where necessary, diagrams are shown of the 
apparatus employed, as well as full directions as to quantities of 
materials to be used in each experiment. 

Observational Astronomi/. By Arthur Mee, F.B.A.8. Second 
Edition. (Western Mail, Limited.) lUustrated. 28. 9d. A new 
edition of this admirable work was, of course, to be expected. It has 
been greatly enlarged, and most of the illustrations are new. Numerous 
representations of the planets, etc., are shown, as well as thumb- 
nail sketches of eminent astronomers ; features which impart to the 
book an interest which is peculiar to itself. In the plate forming the 
frontispiece is given a drawing of Saturn, by Antoniadi, as it appeared 
on July 16th, 1S97. A photograph of the great nebula in Orion, 
by Dr. Roberts, also enhances the value of the work. We have not 
seen a popular book on astronomy for many a day whicli possesses so 
raanv and diverse attractions as this one ; and we hope that its 
circulation may increase in a ratio commensurate with its improved 
condition. 

The First Book of Scientific Knowledge. By Paul Bert. (Relfe 
Bros.) Illustrated. 2s. 6d. We are pleased to observe that a new 
and improved edition of this admirable introduction to the sciences 
has just been issued. It is sufficient to say of so successful a work, 
both in France and in our own country, that the publishers have done 
all that seemed needful to make the volume a solid foundation for 
more advanced study. 



BOOKS RECEIVED. 

Poultry fur the Table and Market versus Fancy Fowls. By W. 
B. Tegetmeier, y.z.s. (Cox.) Illustrated. 28. 6d. 

A New Astronomy. By David P. Todd, pa.D. (American Book 
Company.) Illustrated. Sl-30. 

The Story of Life in the Seas. By Sidney J. Hickson, P.B.s. 
(Newnes.) Dlustrated. Is. 



April 1, 1898.] 



KlSrOWLEDGE. 



89 



The British Colonies : 188R.1S'J7. By Bev. Win. Parr Creswell, M.A. 
(Blackic) 28. 6d. 

Audubon and his Journals. Two Vols. By Maria R. Audubon. 
(John C. Ximmo.) Portraits and Illustrations. 

Ethnological Studies among the North- West-Central Queensland 
Aborigines. Bv AValtor K. Roth. (Queensland Agent-G-eneral's 
Office!) Illustrated. 

The Year-Book- of British Columbia (1897J. (Victoria, B.C.) 

The Natural ffisfori/ of the British Isles : Vertebrates. By F. d. 
Allalo, p R O.S., F.z.s. (Blackwood.) Illustrated. 63.net. 

The Miner s Arithmetic and Mensuration. By Henry Daries. 
(Chapman & Hall.) 48. net. 

TFho's If'ho a.syS). (A. & C. Black.) Ss. 6d. net. 

General Elementarg Science. Bv \ViUiamBrigg3,M.A. (Clive.) 3s. (id. 

The Smithsonian Institution: is4G-lS'J(>. (Washington.) 

Sixteenth Annual Report of the Bureau of American TSthnoloyu. 
(Washington.) 

Das Weltgebiiude. Von Dr. M. Wilhelm Meyer. (Leipzig.) 

A Treatise on Magnetism and Elecfricifif. By Andrew Gray, 
LL.D., F.E.s. Vol. I. (Macmillan.) 14s. 



STARS HAVING LARGE PROPER MOTION. 

A RECENT announcement has been made by Prof. Kapteyn 
that the star Cordoba Z. C. 5h 243 has an annual proper 
motion of 7'5 ", which is larger than that so far found 
for any other star (Astronomische Nachriehten, Vol. CXLV., 
p. 159). 

The effect of this motion is shown in the accompanying 
illustration, which is enlarged nine times from two photo- 
graphs taken with the eight-inch Bache telescope, at the 
Arequipa Station of the Harvard College Observatory. 



■. ^ 



Proper Motion of Cordoba Z. C. oh 243. 

The scale of the original photographs is 180"=01 cm. 
The plates were superposed so that the images of the stars 
on one should be a short distance below those on the other. 
The motion of Z. C. 5h 243, which is indicated by an 
arrow, is at once apparent from the displacement of the 
line connecting the two photographic images of this object. 
The southern of each pair of images, and the right-hand 
image of 5h 243, are reproduced from a photograph taken 
October 8th, 1889, with an exposure of fourteen minutes. 
The northern images are reproduced from a photograph 
taken November 10th, 189G, with an exposure of twelve 
minutes. E. C. Pickering. 



THE LEVEL OF SUNSPOTS. 

By the Rev. Arthur East. 

THAT sunspots are holes in the sun most people 
admit ; that they are black is manifest to everyone 
who has observed them, even with a field-glass ; 
but whether they are raised above or sunk below 
the general level — if there even be a general level — 
and why anything in the sun should be black, are questions 
not so easily answered. That the blackness of the " umbra " 
is probably brighter than the electric light is immaterial. 
Compared to the far brighter photosphere the inner por- 
tions of a spot are black or nearly black. To the superficial 
observer the answer might appear obvious, viz., this: "The 
deeper a hole is, the blacker are the shadows." But it must 




Fia. 1. — Symmetrical .Spot, elevated Penumbra. Black Umbra 

surrouBded by Penumbra; margins of "Spot" depressed below 

general level. 

be borne in mind that we are not dealing with shadows ; 
there can be no such thing on a self-luminous body as a 
shadow, and the reason why one part of the sun is darker 
than another, and even relatively black, is due to an 
entirely different cause, namely, absorption of the light. 
The edge of the sun is darker than the central parts 
because the light from the edge reaches us after passing 
through a vast thickness of solar atmosphere, and this is 
very manifest in photographs of the sun ; for the same 
reason the middle part of a spot appears black because 
the light from below has to traverse the depth of the spot, 
which is known to be filled with comparatively cool and 




Fig. 2. — Symmetrical Spot. Penumbra with dark margin next 
to Photosphere. 

light-absorbing vapour. If the writer has been fortunate 
enough to induce anyone to experiment in the way of 
making artificial sunspots, •'it will have been observed that 
the spots may be broadly classified under four types : — 

1. Spots more or less elevated above the general level, 
with deep central part and gaping orifice, as Fig. 1. 

2. Spots with a cup-shaped orifice, where the ascending 
fluid scours out the sides of the cone of granules, as Fig. 2. 

3. Spots where the hot fluid rushes up obliquely, making 
the sides much steeper in one part than another, as Fig. 3. 

4. And, lastly, spots which are not cone- or crater-like 
in form at all, as the others are, but where the sides recede 
from the orifice, leaving only a black and gaping hole as 
Fig. 4. 

It is not meant that each spot is restricted to any one 
type ; it may belong to two or three, or even all four, in 
different parts of the same spot : e.g., the sides of the 
penumbra may be nearly flat in one place and concave in 
another, and almost vertical in a third ; whilst the older a 

* See article on " Artificial Sunspots " in Knowiedob, December, 
1897. 



90 



kNOWLEDGfi. 



[Apbu, 1, 18d8. 



spot is the larger grows the vent, and the more the crater 
form tends to disappear. And these forms may be modified 
at any stage of development — with this exception, that the 
form in Fig. 4 always comes last. 

Now, if these pulp spots were self-luminous, and seen 
from above and not in section as the diagrams are drawn, 
and if the usual terms used to describe sunspots may be 
used, it is evident that they would, when filled with light- 
absorbing vapours, appear as follows : — 

Fig. 1 would show as a black umbra surrounded by a 
lighter border, this latter being due to the light of the 
photosphere having to travel through a comparatively 
shallow stratum of absorbing vapour ; the black vent or 
nucleus at the bottom of the crater-like spot might or 
might not appear, according to its position in the bottom 
and the clearness of the " seeing." 

Pig. 2 would show as a black umbra surrounded by a 
lighter penumbra, with an overhanging "thatch "at its 
outer edge. 




M t PI 



Fl8. 3. — Unsymmetrical Spot : Penumbra wanting on one side. 

Fig. 3 would appear as an unsymmetrical spot, i.e., with 
the penumbra wider on one side of the umbra than the 
other. 

Fig. 4 would appear as a spot consisting of an umbra 
alone, not surrounded by any penumbra. 

It is easy to see how the Figs. 1, 2, and 3 come to be as 
they are : in the lowest part or vent, the hot vapours are 
confined by the weight of the photospheric matter ; as 
they approach the surface the weight is less, and they are 
able to thrust the granules aside into the crater-like 
form. When the surface is reached they expand more 
suddenly, sometimes making a salver-shaped orifice as 
Fig. 1, and sometimes scouring out the sides into the cup- 
shaped form of Fig. 2. This latter is often beautifully 
shown in the artificial spots, the stray granules playing 
within the hollow in a most realistic manner. 

An objection to these diagrams as truly representing 
actual sunspots will no doubt be made that the umbra is 
often seen when the spot is close to the limb, and that 
therefore a spot must be nearly always relatively shalloir, 
otherwise the umbra would be hidden ; and herein, as in 
the general discussion of the appearance of spots seen 
obliquely, I venture to suggest that there occurs occasion- 
ally a very great fallacy. The text-books say : " Imagine a 




Fig. 4. — Spot without Penumbra, and level with Photosphere. 

saucer with a blackened middle slowly turned edgeways to 
the observer, and see the black part gradually disappear." 
This is quite true of an empty saucer, but a full saucer will 
behave differently, and the black middle in the /'nil saucer 
will apparently keep on rising long after it should have 



been hidden. It is, of course, as everyone knows, refracted 
upwards, owing to the difference in density between the 
water in the saucer and the air through which the observer 
views it ; and a spot is not an nnpty saucer but a full saucer, 




K,G. .-,, — Siin-iN.t-. 'Fn.ii, Sir K E:,ll- '-i,,,-; ut ' ■ - , y 
kind permissiou of Messrs. Cassell £ Co.) 

filled with dense vapour, and doubtless the bottom of the spot 
is refracted upwards more and more as the spot approaches 
the limb, and making it visible long after it apparently 
should have disappeared. Not only will the umbra be 
affected in this way, but the whole of the farther side of 
the spot, causing the curious optical effect of the edge of 
the spot appearing to rise up, and tend to face the observer, 
when, in reality, it of course lies flat on the solar surface. 
To show that these analogies between the form of 
artificial " spots " and the real solar spots are true ones — 
at least, if not wholly, yet in part — I would refer to the 
very beautiful photograph of a sunspot taken by M. 
Janssen, and reproduced by kind permission of the pub- 
lishers of Sir Kobert Ball's " Story of the Sun " (Fig. 5); 




Fig. 6. — Empty Vessel, with black bottom just in view. 

and I would ask the reader to compare one feature in this 
photograph with Fig. 3 of the plate in Knowledge of 
December, 1897. 

There appears in this photograph of M. Janssen's the 
black umbra with a few wandering granules within : the 
lighter penumbra with sides vertical apparently in one 
part, steeply inclined inwards elsewhere ; the brilliant 
bridge extending across the chasm, and the granulated 
surface of the photosphere beyond : but the brightest part 
of the whole plate, except the bridge, is the portion next 
to the penumbra. Looking at it, it is almost impossible 
to doubt that we are looking down upon a vast mnund or 
tiimuh(.^ with a yawning opening and steeply shelving sides 



April 1, 1898.] 



KNOWLfiDGe, 



91 



within, and that the reason for this excessive brightness 
is that the edge of the spot is really protruded to a vast 
height above the general level, and that the brilliance of 




Flii. 7. — The same viewed from identieally the same point, but 
fillei with water. 

that part is to this extent unimpaired by absorption. 
Now the Fig. H, already referred to, gives exactly this 
appearance of an elevated mound with a gaping hollow, 
which, as a matter of fact, it was. 

The appearance of a spot having a penumbra with its 
outer margin the darkest part must be familiar to all 
observers of sunspots ; the photosphere at some points 
seems to overhang the spot — as it probably does. 

But there is one effect caused by this darker part of the 
penumbra coming next the bright photosphere, and the 
brightest part of the penumbra coming next the black 
umbra, namely, that the centre of the spot appears to be 
protruded outwards, in a convex manner — an appearance 
due, in my opinion, to the deceptive shading, as it were, 
in spots of this character, the penumbra being in reality 
wholly concave within. 




sphere by micrometric measurement of the farther side 
of the penumbra is not only impossible, but that the 
results arrived at would be entirely misleading. 

As the nifiiii density of the sun is only about 1- i compared 
with the density of water, it is evident that the vapours on 
the solar surface cannot be of anything like the density of 
the water in the basin ; their density, nevertheless, must 
be very great, the attraction of the sun being more than 
twenty-seven times that of the earth. 



j-jo. s. — The same viewed very obliquely, the bottom apparently 
risen to the top. 

There is just one other point shown in the diagrams. 
Figs. 1, 2, and 3, which may interest some observers of 
sunspots. The weight of the protruded penumbra, resting 
as it does on the photosphere (artificial), depresses_ the 
surface not a little, so that the mouiul is resting in a 
depression of its own making ; and if this condition of 
the penumbra really exists on the sun, it ought to be 
observable on the limb, as a writer m the British Astro- 
n(miic<(l Journal for August, Mr. F. K. McDowall, states 
that he does see it. 

The Figs. 0, 7, and 8 may serve to make clear the above 
contention as to the probable refraction of the umbra. It 
will be seen that, when viewed even very obliquely, the 
black bottom (umbra) is very visible, and suffers but little, 
comparatively, from being viewed in profile. 

It is not contended that spots are very deep relatively 
to the sun's diameter, which is improbable, but only that 
they are very much deeper than they appear to be ; and 
also that to attempt to arrive at the depth of the photo- 



THE EVOLUTION OF THE VENOM-FANG. 

By Lionel Jervis. 

IT would be difficult to name a creature more feared 
and loathed than the deadly serpent ; yet, deprived 
of its fangs, how helpless it becomes ! It is true 
that the great size and enormous muscular power 
of the giant constrictors render them formidable 
antagonists to all but the very largest animals, but these 
monsters are comparatively rare, and are confined to a 
limited number of species. The anaconda (Kunectes 
murinus) from South America, two species of python 
(P. molurus and P. nticulatus) from the East Indies, and 
one (P. seke) from Africa, about exhaust the list of 
unvenomed snakes dangerous to man, though the common 
boa constrictor sometimes attains considerable proportions. 
Generally speaking, however, the non-venomous serpent, 
or the venomous serpent that has been rendered innocuous 
by the removal of its fangs, is quite defenceless against its 
enemies — and they are numerous. 

The mongoose, the hog, and many other animals — not 
to mention man — kill them on sight. It is, indeed, 
wonderful that the harmless species succeed in holding 
their own in the struggle for existence, considering that 
even the most venomous serpents frequently fall victims. 
The hog, for instance, is said to have extirpated in certain 
districts the rattlesnake, which is far from harmless, 
although a very overrated creature, its sluggishness ren- 
dering it a comparatively easy prey. The inhabitants of 
the Lesser Antilles — at least, so the tale was told to me — 
seem to have been unacquainted with this fact, or to have 
overlooked it, and, arguing no doubt that if a hog would 
kill a rattlesnake it would kill a fer-de-lance fLaclwsis 
lanceolatus), they imported swine to keep down the pest ; 
but that was a very different story. Then they tried the 
mongoose ; but the mongoose does not appear to have 
found the business good enough, and turned its attention 
to the fowl-houses — a move which the inhabitants neither 
anticipated nor approved. It would seem from these 
incidents that to interview the fer-de-lance is a risky 
commission, though I believe that the secretary bird was 
domesticated in Martinique with a fair amount of success. 
Thus we see that, although no doubt the object of the fang 
is primarily to render the capture of the prey easy, it is 
also very valuable as a means of defence. 

The first trace of this terrible weapon is found in the 
ophistoglyphs, and to explain its gradual development in 
this family and in the vipers, as well as in the elapine 
and sea-snakes, it will be necessary to say something about 
the normal dentition of serpents. Generally speaking a 
snake has six rows of teeth, one on each side of the 
upper jaw, one on each side of the lower jaw, and one 
on each side of the palate : certain species have 
teeth on the pre-maxiUary bone, but (for the pur- 
poses of this article) this feature is unimportant. Now, 
some snakes appear to have decided that the capture of 
lizards, birds, and " such small deer " as formed their 
prey would be greatly facilitated if the struggles of their 



92 



KNOWLEDGE 



[April 1, 1898. 



victims could be rendered less violent. They seem to have 
been disinclined to exercise or develop their muscular power 
to crush or smother them like the constrictors ; the only 
alternative was to paralyze them. Nature accordingly set 
to work to modify a portion of the salivary gland, and to 
impregnate the saliva wiih venom, or to develop the 
poisonous properties already existent therein. Here, then, 
the serpent had a store of the composition necessary for 
its purpose ready to hand. At the same time a groove 
began to be formed in two or three of the teeth at the back 
of the upper jawbone (that is to say, those below the 
salivary gland), and gradually became deeper, thereby 



of the mouth until it could find shelter in the reserve 
fang which is advanced to take the place of the broken 
or discarded one ; in either of these contingencies it 
would in all probability be irretrievably damaged. In 
reality the duct terminates in the centre of the gum, 
just between the fangs. It frequently happens that a 
portion of the venom goes astray between the opening of 
the duct and the base of the fangs, although they are very 
close together, and the fleshy sheath that covers the 
fangs when at rest, but is raised and crinkled up across 
the gum when the serpent strikes, is said to be instru- 
mental in preventing the poison being ejected right in 




Fig. 1. — Maxillary bone of innocuous colubrine, shovring solid teeth. FlG. 2. — Maxillary of opliistoglyph, showing development 
of back fangs. Fio. 3. — Maxillary of innocuous colubrine, showing solid teeth. FtO. 4. — Maxillary of elapine snake, showing solid teeth 
remaining behind poison-fangs . Fio. 5.— Maxillary of cohra CNaja J, dho-mng almost total absence of solid teeth. Fio. 6. — Maxillary 
of mamba (VendraspisJ, solid teeth altogether discarded. 



forming a channel by which the poison might be transmitted 
into the system of the victim. The snake thus became 
furnished with its poison and the means of injecting it. 
As a last measure— to make quite sure that the animal, 
when seized, should not escape — the poison-fangs became 
somewhat longer than the original solid teeth, and the 
whole machinery of death was complete (sec Figs. 1 and 2). 
The prey is entangled in the front teeth and forced back 
under the fangs. These are then driven home and the 
venom is injected ; the struggles of the victim almost at 
once become feeble and soon cease, when it is devoured at 
leisure. 

This apparatus, though efifectual, is rather clumsy, and 
we find a great improvement in the proteroglyphs. It is 
obviously better to have the fangs in the front of the mouth 
than at the back, as the serpent can then seize its prey 
and inject the poison at one and the same time, instead of 
having to work it under the back fangs before it could 
commence to paralyze it. Before I go any further I should 
like to have it quite clearly understood that the development 
of the fangs of the vipers, which are descended fi-om the 
ophistoglyphs (as I shall endeavour to show later on), is 
in no way connected with the development of the fangs of 
the other proteroglyphs, viz. : the elapines and the sea- 
snakes. In fact, two distinct families of serpents appear to 
have become venomous at about the same time, quite 
independently of each other. 

Accordingly, in the elapines and sea-snakes" two of the 
front teeth on either side of the upper jaw became grooved 
and enlarged, and a channel was gradually formed from 
the gland behind the eye to the base of the fangs. The 
distance, however, between the gland and the poison-fang is 
never great, and the modification of their relative positions 
is more apparent than real. As a matter of fact the fangs 
are always either nearly under the eye or close in front of it. 

For many years it was believed that the duct from the 
gland to the poison-fang was continued into the fang itself, 
but research has shown that this view is entirely incorrect. 
The functional fang is frequently either broken off or 
shed, in which case the end of the duct would either be 
carried away or left to dangle unprotected in the front 




Fig. 
(much enlarged) 



* One species of sea-snake (Distira semperi) is confined to a fresh- 
water lake in Luzon. 



front, and in directing it down the channel and into the 
wound. To prevent the venom escaping when the snake 
is using its jaws without the intent of poisoning, a strong 
binding muscle is placed close up to the front of the duct. 
The groove is much deepened and the edges 
have come closer together, forming a more 
perfect channel for the passage of the poison ; 
in fact, in the genus Klaim (the coral snakes) 
the fang has come to have the appearance 
of being perforated. The poison - gland 
itself is much enlarged — in one case 
(Doliophis) eccentrically so, for it is ex- 
tended about a third of the way down 
the body, thereby further upsetting the 
already disordered internal arrangements of 
the serpent — and round it is twisted the 
anterior temporal muscle, so that it can 
be violently compressed and the poison 
squirted deep into the wound. It can be 
readUy seen that this machinery, even in 
its undeveloped stages, is a great improve- 
ment on the back-fanged arrangement. . , - , 

T ,1 1- r i-a of elapine snake, 

In the earlier forms numerous solid growing groove, 
teeth continued to exist behind the poison- 
fangs, as can be well seen in the sea- 
snakes, and in the less specialized elapines ( Figs. 3 
and 4) — examples, Glyphndon and Pseuddnps from New 
Guinea and the neighbouring coimtries. The serpents, 
however, with their new and formidable dental armature, 
began to discover that the envenomed wound caused by 
their bite paralyzed their prey so quickly that it became 
less and less necessary for them to retain their hold in 
proportion as the poison apparatus became more and more 
developed, and consequently the solid teeth on the maxil- 
lary bone became useless and gradually disappeared ; so 
that in the cobra [Xirja), in which the fangs are highly 
specialized, we only find two or three left (Fig, 5), while 
in the Eing Hals snake {Scpcdon), the coral snake 
(Elaps), a,nd in the mamba {l\'7idiaspis) (Fig. 6), they are 
altogether wanting. 

In some cases the fangs have grown so large that it has 
become imperative to provide for a certain amount of 
motion in the maxillary bone, so as to allow them to point 
slightly backwards when the month is shut, and to avoid 



April 1, 1898.] 



KNOWLEDGE. 



93 




wounding the lower jaw. Of course, when the snake is 
about to strike, the fang has to be raised again ; and with 
this object certain modifications have been made in the 
bones of the palate, and certain muscles have been requi- 
sitioned to govern the necessary motions, to explain which 
in detail would require another article as long as this one. 
By means of this complicated machinery the fang of the 
cobra (Fig. 5) can be erected and depressed to a limited 
degree, though not to anything like the same extent as in 
the case of the vipers. In the mamba, however, the diffi- 
culty has been overcome in another way : the maxillary 
bone is lifted in front and curved backwards (it is shaped 
something like a sickle with about six inches of the point 
broken off, held edge downwards i, so that the base of the 
fang is considerably above the roof of the mouth (Fig. 6). 
Now, these long, sharp, delicate weapons are extremely 
likely to be broken off, and it is very necessary that there 
should be a reserve of fangs to take their place in case of 
accidents. Consequently, behind the functional fangs are 
others in every stage of development : the minute germ, 
the more markedly grooved tooth, and so on to the per- 
fectly developed functional fang, with the edges of the 
groove nearly joining in front (Fig. 7). This being so, the 
necessity for taking any 
particular care of the 
front fangs of course 
ceases to exist ; indeed, 
it appears that they are 
not unfrequently shed 
voluntarily. 

While the sea-snakes 
and elapines were thus 
being armed, the back- 
fanged snakes (ophisto- 
glyphs) were slowly 
becoming front - fanged 
snakes (proteroglyphs ) also. As regards the poison-gland 
(with the exception of the exaggerated development of 
the Dvliiipliis), the duct, and the fang-sheath, the same 
principles are in evidence ; but the maxillary bone has 
been modified and turned up in front, the solid teeth 
in front of the grooved fangs have been discarded 
(Fig. 8), and the fangs themselves have come into position 
in the front of the mouth— or, rather, to be more accurate, 
the front of the mouth has come back to the faugs. 
At the same time the edges of the groove have gradually 
closed up, until at length they are fused, and have the 
appearance of being tubular (Fig. 9) — an appearance 
which has deceived many into the belief that the fang is 
actually hollow or perforated. If the fang be bisected, 
however, the error at once becomes evident, for the section 
will show the semicircle of pulp completely surrounded by 
dentine (Fig. 10). Thus came the vipers. It is true that 
for many years it was considered that the fang machinery 
of the viper was merely a specialization of the elapine, 
and it is to Mr. Boulenger's researches that we owe the 
true solution of the question. In the less specialized 
forms of viper, such as the Cape viper (Caiisits rhombeatux), 
"the fangs," to quote his words, " are situated on the 
posterior extremity of the maxillary, close to its articula- 
tion with the ecto-pterygoid — a condition which is identical 
with that of the ophistoglyphous colubrids." In the more 
highly specialized vipers, such as the crotalines and the 
atractaspis, the maxillary bone has fallen away altogether 
in front of the fangs. It is hardly necessary to say that 
in this family the soUd teeth which were originally in 
front of the back fangs have altogether disappeared. 

Having, as I have said, the fangs already grooved and 
elongated before their position was altered from the back 



Fio. 8. — Portion of skull of viper 
(rattlesnake), showing the vertical 
position of the maxillary. 



I 



Pia. 9.— Fang (much 
enlarged) of viper ; a, 
ori6ce by which venom 
enters fang ; b, orifice 
through which venom is 
injected into wound 
(much enlarged). 



to the front of the mouth, it became doubly necessary 
for the vipers to have the maxillary bone movable. 
There was not much difficulty in 
,-■''" this, as that bone had already so 
changed as to lie almost vertically 
to the jaw instead of parallel with 
it (Fig. 8), there being only just 
sufficient space left on its tooth- 
bearing face to admit of a single pair 
of fangs. It was a comparatively 
easy process, then, that this face 
should become normally directed 
towards the throat, with the fangs 
shut back, as it were, like the blade 
of a clasp knife, on the roof of the 
mouth ; and that by a modification 
of the structure of some of the bones 
in the front of the skull, and by an 
exaggeration of the action of the 
motor machinery already referred to, 
it should be possible for the snake to 
erect its fangs vertically to the upper 
jawwhen it was striking. It is almost 
superfluous to say that the fangs, 
having in their new recumbent posi- 
tion much more room to grow in than when they were at the 
back of the mouth, have availed themselves of the space at 
their disposal to the fullest extent, some of them reaching 
almost to the back of the palate. It is natural, then, that 
the mobile erectile fangs of the viper should be longer than 
the practically immovable fangs of the elapine. I trust 
that no one will be misled by this sentence into the erro- 
neous idea that the fang itself is movable : the fang ia 
always and quite immovable ; it is the maxillary bone, to 
which the fang is attached, that moves. 
The viper of vipers, the most highly 
specialized of the group, is the 
atractaspis from Tropical Africa. The 
solid teeth on the lower jaw and palate 
have almost altogether disappeared — 
there are only about eight or ten all 
told — and the poison - fangs are so 
enormously developed that Mr. Wood, 
in his popular but not over reliable 
natural history, suggests that the 
atractaspis cannot open its mouth sufficiently wide to 
erect its faugs, and that the poison is injected while the prey 
is being swallowed. If this view were correct, it would be a 
case in which ultra-development had defeated its own end, 
for the serpent would find itself in the same position as 
regards injecting its poison as when it was in its back- 
fanged position — or, rather, in a worse one, for it would 
have no solid teeth to secure its prey with. But of course 
Mr. Wood's supposition is incorrect. The gape of the 
viper is enormous ; it can easily open its jaws to an angle 
of one hundred and eighty degrees ; so that it ia quite 
clear that, however long the fangs may be, there is plenty 
of space in which to erect them — unless, indeed, they were 
to grow right down the throat. 

Specimens of these different families are usually to be 
found in the reptile house at the Zoological Gardens, except 
the sea-snakes, which die almost at once in captivity, how- 
ever large the tank. The ophistoglyphs are usually repre- 
sented by the Cape bucephalus ( Dispholidus tiipus) and 
some species of sand-snake t PsammopJiis J : the elapines 
by the cobras, and what they are pleased to call death- 
adders (as a rule the Pseudechis porphyriacus ) : and the 
vipers by one or two pit-vipers. They have a cotton- 
mouth ( Ancistrodon piscivorusj there now and a fer-de- 




Fio. 10. — Section 
of fang of viper; a, 
dentine ; b, pulp 
(much enlarged). 



94 



KNOWLEDGE 



[Apbil 1, 1898. 



lance. The other species of viper do not as a rule thrive 
in captivity, though the cerastes seem to be doing well 
enough, and there is usually a pufif-adder ( Bids arictanaj 
on view ; but, as I believe they lost thirteen of these 
last year, this is probably due to a large number being 
generally available. At the present moment they have a 
mamba there, and a true death-adder f^ca«(/«)/i)s ((»«<(?■(■- 
ticusj, both elapine snakes, which I understand to be the 
only serpents of these species ever exhibited in this 
country. 

It may be interesting to those who are inclined to be 
sceptical to know that the theory as to the derivation of 
the vipers from the ophistoglyphs has been recently 
confirmed by researches on the venom-glands of snakes. 
To attempt to give even an outline of these conclusions 
would, however, exceed the scope and limits of this article, 
and it will be sufficient to refer intending students to the 
paper of M. Phisalix on this subject. 



NOTES ON COMETS AND METEORS. 

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

CoMETARY Discoveries. — The total number of comets 
observed sufficiently well during the last thirty years 
(1868-1897) for their orbits to be calculated amounts to 
one hundred and thirty-five, but of these thirty-seven were 
returns of periodical comets which had been previously 
seen. The average rate of apparition of new comets has, 
therefore, been 3-27 annually, and of new and periodical 
comets 4-r, annually. In 187.S, 1881, 1892, and 1896, 
seven comets were discovered ; in 1872 not one was 
observed ; and in 1875 the only two comets which 
appeared were known ones. The best months for the 
discovery of these objects appear to be July and August. 
Of three hundred and twenty-eight comets discovered 
between the years 1782 and 1897 inclusive, the following 
are the numbers found in the various months : — 



January 


. 22 


July 


37 


February 


21 


August 


43 


March 


. 24 


September . . 


. 25 


April ... 


.. 27 


October 


26 


May ... 


20 


November 


. 34 


June ... 


22 


December 


27 



These figures include every description of these bodies. 
During the sixty years from 1782 to 1841 there were 
eighty-seven comets, averaging 1-45 per year ; but during 
the fifty-six years from 1842 to 1897 there were two 
hundred and forty-one comets, averaging 4 -Hi) per year. 

Ponx-Winnerkc's Comet. — -This comet is now too faint 
for observation, and is, moreover, unfavourably placed in 
the morning twilight. Its position during the next few 
months is indicated by Hillebrand in Ast. Ndch., 3480, as 
follows for Berlin noon : — 



1898. 

April 8 

„ 24 

May 14 

June 3 

„ 23 



R.A. 



Declination. 



22 51 56 -11 51 

5 21 —7 32-5 

1 11 59 -3 21-2 

2 6 82 -fO 1-4 
2 49 35 +2, 10'9 

Perrine's Comet, 189G, VII.— In Ast. Naeh., 3478, Hans 
Osten, of Bremen, gives definitive elements for this comet. 
It was observed from 1896, 8th December, to 1897, 1st 
March, and was visible, therefore, for twelve weeks. He 
finds the period 2352-5 days, or 6'441 years, with a probable 
error of 6-8 days. This result agrees exactly, as regards 
periodic time, with that given by Ristenpart in Ast. Xach., 



3402, based on observations in 1896, December, and 1897, 
January. At the time of the comet's next return in 1903, 
April-May, there is little prospect that it will be observed, 
as it will pass through its perihelion when the earth is on 
the other side'of the sun. In 1909, October, however, the 
conditions will be extremely favourable. 

Fireballs of 1898, February 20ih. — On this night two 
large meteors were seen, their times of apparition being 
8h. 54^m. and lOh. 20m. The former was observed by 
many persons, and some of the details were as follows : — 

Cliidilingfold, Surrey. — Brilliant meteor passed close 
under Procyon and pursued a straight course through the 
middle star of Orion's belt to about ten degrees beyond, 
when it was lost sight of behind the roof of a house. The 
colour was that of the arc electric light. Nucleus pear- 
shaped, leaving a trail. When about midway between 
Procyon and Orion it [blazed up, emitting sparks ; then 
became much fainter until past Orion, when it blazed 
again, and then again faded. The meteor seemed to be 
moving very slowly to the west, and remained in sight 
about three seconds, during which time it travelled throut;h 
about fifty degrees of arc. — Rear-Admiral Ma( lear. 

Ealing, Middlese.r. — Meteor of exceptional size and 
brilliancy appeared in due south at altitude of about 
twenty to twenty-tive degrees, and travelled to west, at 
first slightly ascending and then descending. Light 
greenish, and it left behind a long, broad, livid streak. At 
middle of flight it threw off numerous small pieces of 
slightly redder tint. Duration of flight, four seconds. — 
0. J. Preston. 

Freemantle, Southampton. — Splendid meteor; emitted a 
brilliant blue light which lit up everything around. Quite 
stationary for several seconds before it sped away due 
south, leaving a trail of thousands of sparks behind it. 

Hiirriujati-, Yorks. — Very brilliant meteor low down in 
south sky. Apparent motion slow, and it was observable 
for about four seconds. It left a long trail. — J. G. C. 

Edghaston, Iiiniiiniili(im. — Brilliant meteor seen low down 
in the south (about the height of the middle of the small 
stars under Sirius). — W. Abthdr Smith. 

Wedtunlniri/. — Magnificent meteor, of an intense orange 
colour, and leaving a long train of sparks ; travelled a long 
distance from east to west, and finally disappeared appa- 
rently just under Sirius. — T. F. Bissell. 

Clifton, Bristol. — Brilliant meteor appeared rather low 
in the south-eastern sky, and travelled slowly in a westerly 
direction along a nearly horizontal path. Visible for 
several seconds, and disappeared nearly in the south. — 
R. F. Sturge. 

WimbU'dioi. — Walking along a road facing south the 
meteor came into view in front of me, a little to the right of 
my course, and about two-thirds up towards the zenith. It 
travelled quite slowly towards the west. Interior blue 
with an outer edge of red. It appeared to me a little less 
than half as large as the full moon. — E. J. R. Radcliffe. 

Westminster. — Meteor brighter than Venus, bluish white, 
swift. Path, 111° -t-5" to QT-IT.—W. E. Besley. 

Xeiiburi/. — A large and brilliant luminous body travelled 
across the heavens in a nearly straight line from east to 
west. Visible for several seconds. It illuminated the entire 
district. 

Chichexter.^Shot athwart the zenith, crossing the clear 
open space directly overhead, and leaving a trail of sparks. 
It moved with slow apparent velocity, and passed north of 
Pleiades before itdisappearedbehindclouds. — A.Roshridge. 

Without attempting to reconcile these and other accounts 
it seems that the meteor appeared over the English Channel, 
and fell from a height of sixty-one to twenty-seven miles. 
When first seen it was above a point thirty-three miles 



April 1, 1898.] 



KNOWLEDGE 



95 



south of Beachy Head, and moving almost due west ; it 
disappeared thirteen miles south-east of St. Alban's Head. 
The earth point is indicated near Teignmouth, and the 
length of observed path was ninety-five miles. Taking 
the duration as four seconds, the velocity will be twenty- 
four miles per second. The radiant point was at about 
17(> + 12' near /? Leonis, and it agrees with the position 
of a long-enduring meteor shower. 

The tireball which appeared at lOh. 20m. on the same 
evening as the one described above, was not observed with 
sufficient fulness to enable its path to be determined. 

FiREBAi,L OF March 12th, 7h. 5m. — A very brilliant object 
of this class was observed at Slough and St. John's \\'ood, 
London. The nucleus was globular, and traversed its path 
with moderate velocity, leaving a long train behind it. 

Tlu' Ajiiil Lijriils. — This shower will be due on April 
19th-"20th, and, the moon being absent, the conditions will 
be highly favourable for witnessing any display that may 
occur. The periodical maxima of this stream probably 
recur at long intervals, for its parent comet has a com- 
puted time of revolution of four hundred and fifteen years. 
There was, however, a brilliant display of Lyrids on the 
morning of April 20th, 1803. This shower is usually by 
no means rich, but it requires further observation. Its 
radiant point is at 270^+ 32 \ and it probably travels east- 
wards during the very few nights of the shower's visible 
activity. 

♦ 

THE FACE OF THE SKY FOR APRIL. 

By Herbert Sadler, f.r.a.s. 

SOJIE spots still occasionally diversify the solar disc. 
Conveniently observable minima of Algol occur 
at Oh. 15m. a.m. on the 13th, and 9h. Im. p.m. 
on the 16th. 

Mercury is an evening star, and is very favour- 
ably situated for observation during the first three weeks 
of the month, but afterwards he approaches the Sun too 
closely to be visible. He is at his greatest eastern elonga- 
tion, 19i', on the 11th. On the 1st he sets at 8h. 5m. 
P.M., with a northern declination at noon of 11° 38', and 
an apparent diameter of 6''. On the 11th he sets at 
8h. 50m. P.M., with a northern declination of 17- 45', and 
an apparent diameter of 8 '. On the 23rd he sets at 
8h. 26m. P.M., or about one hour and a quarter after the 
Sun, with a northern declination of 18 '39', and an 
apparent diameter of 10| '. While visible he describes a 
direct path in Aries, without approaching any conspicuous 
star. 

Venus is too near the Sun to be conveniently observed 
this month. 

Mars is technically a morning star, but his diameter is 
so small that it would be useless for the amateur to expect 
to see any indications of markings on his surface. 

The minor planet Vesta is in opposition to the Sun on 
the 6th of May, with a stellar magnitude of 6-0. However, 
she is conveniently situated for the amateur observer 
during the last half of April, so we give a short ephemeris 
of her. On the 15th she rises at sh. 18m. p.m., with a 
southern declination at transit of 6 52'. On the 25th she 
rises at 7h. 29m. p.m., with a southern declination at 
transit of 6 IS'. During the month she pursues a retro- 
grade path in Libra. 

•Jupiter is an evening star, rising on the 1st at oh. 26m. 
P.M., with a southern declination of 0^ 20' at noon, and 
an apparent equatorial diameter of 41^'. On the 9th he 
rises at 4h. 39m. p.m., with a northern declination of 0° 2V, 
and an apparent diameter of 44". On the 16th he rises 



at 4h. 27m. p.m., with a northern declination of 0° 21', 
and an apparent diameter of 44". On the 23rd he rises 
at 3h. 55m. p.m., with a northern declination of 0° 37', 
and an apparent diameter of 43 V'- On the 30th he rises 
at 3h. 24m. p.m., with a northern declination of 51', and 
an apparent equatorial diameter of 43". During the 
month he describes a retrograde path in Virgo. 

As Saturn does not rise till 9h. 50m. p.m. on the Ist, 
with a great southern decUnation, and Uranus is as badly 
situated, ephemerides would be useless. 

Neptune has left us for the season. 

There are no very well marked showers of shooting stars 
in April. 

The Moon is full at 9h. 20m. p.m. on the 6th ; enters 
her last quarter at 2h. 28m. p.m. on the 13th ; is new 
at lOh. 21m. p.m. on the 20th ; and enters her first quaiter 
at 2h. 5m. a.m. on the 29th. 



<[K{)css Column. 

By C. D. LooooK, b.a. 

Communications for this column should be addressed to 
C. D. LococK, Burwash, Sussex, and posted on or before 
the 10th of each month. 



Solutions of March Problem. 
Key-move. — 1. B to E7. 
If 1. ... P to R7, 2. E to KKte, etc. 
1. ... K to R7, 2. K to Kt4,etc. 
Correct Solutions received from Alpha, J. T. Blakemore 
G. J. Newbegin, Capt. Forde. 

H. S. Brati'lntli (Algiers). — Solutions of February 
Problems correct. 

Alpha. — The laws of the British Chess Association, 
approved by Mr. Steinitz in his " Modern Chess Instructor," 
allow a Pawn to decline promotion. By common consent 
this " dummy Pawn " is no longer allowed in problems. 

P. G. L. F. — Many thanks ; they shall appear next 
month. 

J. T. Bliikemore. — It sounds good ; have had no time to 
examine as yet. Your other suggestion comes just a day 
too late to be adopted. The game, however, is so short 
that we thought one diagram rather liberal in the way of 
illustration. 



PROBLEM. 

By A. C. Umlauff. 

Black (7). 



♦ # 5 i 






WB M 



P .^,^..1^/ 

% 2 






White (7). 

White mates in three moves. 



96 



KNOWLEDGE 



[April 1, 1898. 



CORBESPONDENCE GAME. 

(Concluded.) 
Position after White's Thirteenth Move 

Black (i:). 




14. Q to ESeh (j) 

15. QxKtP 

16. Kt to Q2 (l) 

17. P to KKt3 (m) 

18. Kt to K4 (o) 

19. R to Qsqeh 



Black. 

13. R to Q4 (J) 

14. K to Q2 

15. ExP (/.') 

16. R to KKt4 ! 

17. KB to B4 (n) 

18. QxKt 

19. B to Q4 



Notes. 

(i) The most attacking continuation. 13. . . . Q to Q5 
■would be perfectly safe, as Black must exchange Queens 
with a slightly inferior development. 

(j) He should certainly keep the check in reserve. 
Other continuations are most interesting, cr/. ■ — 

I. 14. Kt to B-l (.'), RxP; 15. E to Qsq, B to Q3 (if 

15. P to KKt3, Q to E6, threatening Q x Rch ! as well as 
E to KE4) ; 16. Q to E8ch (?J, K to Q2 ; 17. Q x E, and 
Black mates in four moves. 

II. 14. Kt to tji', B to KKt5; 15. Kt to B3 (if 15. Kt to 
B4, B to QB4 ; and if then White checks and wins the R, 
Black mates in two moves), 15. . . . BxKt; 16. PxB, 
RxP (or ... P to KKt4!); 17. E to Qsq, E to Q4 ; 
18. B to K3, Q to E6 (threatening B to Q3) ; 19. R x R, 
P X R ; 20. P to KB4, P to KKt4, etc. 

III. 14. B to KS! RxP; 15. R to Qsq (if 15. Kt to 
Q2, B to Q4), 15. ... B to Q4 (or a) ; 16. Kt to B3 ! (if 

16. P to QB4, Q to KKt5, or Q x BP). 

(a) 1>. . . . B to Q3 ; 16. Q to RHch, K to Q2 ; 17. 
Q x R, E X B ; 18. P to KKt3, Q to Kt5 ; 19. Kt to B3, 
R moves, etc., with a good game. 

IV. 14. Pto£:A'(3(.'), QtoR6(orQtoQ5); 15.BtoB4, 
B to QB4; 16. Q to RBch, K to Q2 ; 17. QxR, B to 
KKt5! (17. ... RxP, or 17. ... R to Q7, is very 
tempting, but is met by 18. Kt to B3, the only move in 
each case) ; IS. P to K6ch, K to K2 ; 19. R to Ksq (best) 
(if 19. PxP, Black mates in three moves), 19. . . . 
B X Pch probably wins. 

(/,•) 15. . . . B to QB4 would threaten Q xPch, but is 
much inferior to the Rook's move. 

(l) Natural enough, but he overlooks the bolt from the 
blue. In any case he has a bad game now. 

(jn) There is no good defence to the numerous mates 
latent in the position, e.g. : — 

I. 17. Kt to B3 (or anywhere except to K4), RxPch 
and wins. 

II. 17. R to Ksq, Q to R6 ! 18. P to KKt3, B to Q4 ; 



19. Kt to K4, E to E4 ; 20. B to B4, Black mates in 
three moves. 

III. 17. P to KB4, B to B4ch ; 18. K to Esq, RxP 
and wins. 

IV. 17. R to Qsq, RxPch; 18. KxE, Q to Kt5ch wins, 
v. 17. Q X RP, Q to R6 (B to Q4 is even stronger j ; 

18. P to KKt3, B to Q4 ; 19. P to KB3, R x Pch. 

VI. 17. Kt to Ki, E X Pch (or a ; but if 17. ... R 
toQKt4, 18; QxEP, QxKt; 19. E to Qsqch prolongs the 
game); 18. KxE, BtoEGch! 19. K to B3 (best), Q to 
Kt5ch ; 20. K to K3, B x E and wins, for if 21. Q to Kt3, 
P to KB4. 

(a) 17 BtoQ3(?); 18. Pto KKt3 (?) (or i.), Q xKt; 

19. B x E, B to Q4 ! 20. P to KB3, B to B4ch ; 21. K to 
Kt2 (if 21. K to Esq. mate in two), 21. ... Q to K7ch ; 
22. K to E3, B to K3ch ; 23. P to Kt4, B to Q3 ! and 
wins. 

(i.) 18. KttoKtS! Eto KR4 ; 19. Pto KE3, BxP; 

20. E to Qsq ! (not 20. Kt x E, on account of the winning 
reply, Q to Kt5). 

yn) Much stronger than the more showy move, 17. . . . 
B to Q4 (threatening Q x EPch), for White could then 
reply 18. Kt to B3 (forced), BxKt; 19. BxE, QxB 
(best) ; 20. Q X EP, B to Q3 ; 21. KE to Ksq, etc. The 
waiting move made leaves White absolutely without re- 
source. 

(o) Any reader who may have persevered so far will be 
able to work out for himself the forced (and in some cases 
beautiful) mates resulting from any other move. We give 
only one variation: 18. E to Qsq, RxPch; 19. K to 
Esq (A), B to Q4ch ; 20. Kt to B3 (or 20. P to B3, Q to 
Kt5!), 20. ... R to Kt8ch; 21. ExE, QxBP! 

(a) If 19. K to Esq, R to KtSch ; otherwise Q x Pch, 
B to Q4ch, and Q to B6ch. 



KNOWLEDGE, PUBLISHED MONTHLY. 



Contents oi No. 148 (February). 

The Floor of u Contiueut. By 
Grenville A. J. Cole, m.r.i.a., 

F.G.s. {lUuhtratcd) 25 

Eccuiomic Botany. By John E. 

Jackson, a.l.s., etc., 28 

From a Hole in the Mudflats. By 
Harry F. Witherby, F.z.s., 

M.B.o.c. (Ulustraled) 29 

Liqnid Fluorine. By C. F. 
Townseud, f.c.s. (Illustrated) 31 

Letters 33 

British Ornithological Notes 36 

Science Notes 37 

Notices of Books 37 

Total Solar Eclipse, January 22nd, 



Contents of No. 149 (March). 

PAOE 

The Total Solar Eclipse, January 
22,1898. By E.Walter Maunder, 
F.E.A.S. (lUvMrntti) 49 

British Bees, — I. By Fred. Enock, 
F.L.S., F.E.S., etc. [UlusirateA) 50 

The Vinesrar EeL By C. Ains- 
worth Mitchell, b.a., f.i.c 53 

Botanical Studies. — II. Coleo- 
chaete. By A. Vanghan Jennings, 
F.L.S., F.o.S. {lUustrated) 54 

Cloud Belts. By Wm . Shackleton, 



F.E.A.S 



56 



Photograph of the Spiral Nebula 

Messier 33 Trianguli. By Isaac 

Roberts, D.sc, F.R.S 39 

Moon in Eclipse, January 7th, 

1898. By L. Paxton 40 

The Spectra of Brisht Stars. By 

E. W. Maunder. F.K.A.s 40 

Ancient Red Deer Antlers. Bv 

E.Lydekker,B.A.,F.B.s. (Illiis.) 43 
Notes on Comets and Meteors. 

B.7 W. F. Denning. F.E.A.S 46 

The Face of the Sky for February. 

By Herbert Sadler. F.R.A.S 47 

Chess Column. By C. B. Locock 47 

Plate.— Spiral Nebula Messier 
33 Trianguli. 



A New Theory of the Milky Way. 

ByC. Eastoo 57 

Letters 60 

The Masses and Distances of 

Binary Stars. By J. E. Gtore, 

j F.E.A.S (12 

i Science Notes 63 

i Notices of Books 63 

] British Ornithological Notes 66 

Obituary 67 

The Karkinokosm, or World of 
Crustacea.— II. By the Rev. 
Thomas R. R. Stcbbing, ma., 

F.E.S., y.L.S. {llhu^trateA) 67 

Notes on Comets and Meteors. 

By W. F. Denning, f.b.a.s. . 70 
The Face of the Sky for March. 

By Herbert Sadler, f.e.a.s, 71 

Chess Column, By C, D. Locock 71 
Plate,— The Equatorial Cloud-Belt. 



The yearly bound volumes of Knowledge, cloth gilt, 8s. 6d., post free, 
Bindin? Cases, Is. 6d, each ; post free. Is. 9d. 

Subscribers' numbers bound (inclu<iing case and Indes), 23, 6d. each volume. 
Index of Articles and Illustrations for 1891, 1892, 1894, 1395, 1896, and 1897 
can be supplied for 3d. each. 



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8s,, post free. 



Mat 2, 1898.] 



KNOWLEDGE 



97 




Founded in l88i by RICHARD A. PROCTOR. 
LONDON: MAY 2, 1898. 



CONTENTS. 



British Bees.— Hi. Bv Feed. Enock, f.i.s., f.e.s., etc. 

{Illustrated) ... " 

A Valley on Sao Nicolau, Cape Verde islands. By 

BoTD AlEXAXDEB, ST.B o.u. {Illustrated) 
Deserts and ttieir Inhabitants. Bt K. Ltdekker, b.a., 

P.R.S. ... 

The Karktinokosm, or World of Crustacea,— ill. By 
the Kev. Thomas R. R. Stebbiso, m.a., f.b.s., f.l.s. 
(Illustrated) 

Nebulae and Region round y Cassiopeiae. By Isaac 

EOBBBTS, D.SC, F.K.S. {Plate) 

The Recent Eclipse. By E. Waltee Maunder, f.e.a.s. 

{Illustrated) '. 

Notices of Books 

Books Rkceitsd ... ... ... 

British Ornithological Notes. Conducted by Haebt F. 

WiTHEEBT, F.Z.S., M.B.O.U. . . 

Science Notes 

Letters : — Wm. Shackleton {Illustrated) ; Eer. W. Srn- 
ORBAVEs (Note by E. Waltee MArNDEE) {Illustrated) ; 

G. KOBTHOTEB SiRETTOX ; C. B. HOIMES 

Nature's Finer Forces. — Some Notes on Old Work 
and New Developments. By H. Sxowde.v Ward, 

F.H.P.S. ... ... 

Botanical Studies. — III. Jungermannia. ByA.VAroHAX 
Jexnings, f.l.s,, F.Q.S. {Illustrated) 

Notes on Comets and IVIeteors. By W. F. Dknsino, 
F.E.A.S 

The Face of the Sky for May. By Heebeet Sadleb, 

F.R.A.5. 

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



97 
100 
101 



107 
109 
111 



114 

115 

US 

119 
119 



BRITISH BEES.-III. 

By Fred. Exock, f.l.s., f.e.s., etc. 

IT is only when we come to examine the burrows of leaf- 
cutter bees and dissect the newly formed cells, that we 
begin to realize the marvellous ingenuity displayed in 
their construction. AVefind that generally the founda- 
tion is formed of a circular piece of leaf, which the bee 
has so rammed down that it fits into the rounded end of the 




Fig. 12.— Foundation of First Cell. 

burrow (Fig. 12). The bee, having satisfied itself with its 
work so far, next proceeds to exhibit such high intelligence 



that we are bewildered with the thought, " Where does so- 
called instinct end and reasoning power begin ?" The bee 
does not hesitate in its work, but as soon as the circular 
piece of leaf is fixed it seems to recognize in a moment that 
it would not do to attempt to form the sides of the cells of 
circular pieces; accordingly, without compasses or two-foot 
rule, or any other means of measurement than her unerring 
eye and powerful mandibles, in a few seconds she has cut 
an oblong wedge-shaped piece of leaf (Fig. 13), which she 




Fig. 13. — First Side-piece cut and carried. 

carries to her burrow, and, taking it down thin end first, 
carefully places that end in the saucer-shaped foundation 
(Fig. 11). Another oblong wedge-shaped piece of leaf is 
cut and carried home and down the burrow, and once more 
our "superior intellect " is humbled when we find that the 
bee shows still greater common sense in depositing the 
second piece than the first, for she so fits it that one edge 
just overlaps that of the first (Fig. 15). Another visit to 
the bush outside furnishes an exact counterpart of the first 
and second oblongs, fixed in the same methodical manner 
(Fig. 16) ; but still the circle is mcomplete, and for the fourth 




time the untiring architect leaves the nest for the stores, 
from which it again cuts an oblong, and as quickly returns 
to its burrow, and so carefully and correctly has it measured 
the circumference that this fourth piece fits in. just 
overlapping both the third and first pieces (Fig. 17). 
Owing to the wedge shape of these four pieces the cell 
is not by any means fit to receive the nectar and 
pollen for which it is intended. The bee still works 
on, cutting another oblong from a leaf, which she places 
exactly midway over the joint of the first and second 
(Fig. 18), and so on until she has completely closed every 



98 



KNOWLEDGE. 



[May 2, 189g. 



opening at the sides. Sometimes she places an additional 
thickness both at the bottom and at the sides. The cell 
now is ready for the " pudding," and the bee goes out 
to gather the ingredients from the flowers — notably 




Fig. 15, — Second Side-piece fiied. 

those of the campanula. Having filled her reservoir with 
nectar and covered her body with pollen, she flies off to 
her burrow, and quickly divests herself of her load. 
Carefully brushing the pollen from her abdomen, and 
ejecting the nectar from her honey stomach, she proceeds 
to mix the two into a " pudding," to the best of her ability, 
30 that it will not disagree with the stomachs of her 




Fig. 16.— Third Side-piece fixed. 

progeny. Many journeys are made before a sufiicient 
supply is collected, and the cell filled to within a certain 
distance of the top. When this point is reached, the bee 
lays a single egg on the top of the pudding (Fig. 19 j. Having 
taken so much trouble to build up this wonderful cell, it 
is not surprising to find that she next proceeds to protect 
her property. She makes another journey to the bush, 
and cuts out a circular piece of leaf, which she fits into 
the cell so carefully that it does not press upon the delicate 
egg ; and, to make assurance doubly sure, she not un- 
frequently places as many as a dozen of these circular 
covers superposed on each other, a short space being left 
from the last cover to the top edge. As soon as this first 
cell is finished and sealed up, she proceeds to buUd the 
second, the end of which fits into the first (Figs. 20 and 21). 




i'lG. 17. — Foui'tli Side-piece fixed. 

In this way the industrious bee continues her work as 
long as the sun continues to shine, until she has placed 
from nine to a dozen cells in her burrow, the entrance to 
which is then carefully closed with sand ; a few broken bits 
of dead leaves and heather bells are scattered about, and 



no trace is left. Should the weather continue bright, the 
bee sinks another burrow, which she fills with cells, and 
sometimes she will make others before her energies are 
exhausted. 

Other marvellous work lies hidden under the sand, but 
nature is carrying on her transformations. The eggs hatch 
into legless maggots, that find their food ready to their 
mouths (Fig. 22); a few weeks of such sweet food brings them 
to full growth, and they are ready for their next change — 
the chrysalis. Before that stage is reached, however, they 




spin themselves a silken shroud, and fastening the silk to 
the sides and ends they turn themselves round and rest 
upon their backs, with their heads pointing to the entrance 
of the burrow (Fig. 23). In this position they assume the 
chrysalis stage, in which they remain for at least a month. 
During this time the changes of colour and gradual forma- 




FlG. 19 Section of First Cell, -bowing Pudding and Egg. 

tion of the bee may be watched. At first there is but little 
difference in the form, but in a week the limbs are all 
plainly visible. The eyes and mandibles then begin to 
assume distinct shape and colour, and the various parts of 
the delicate tongue can be traced out under the membrane 
which encloses the whole of the body. In a fortnight the 




joints appear and then the hairs on various parts, and in 
a month's time the bee appears quite ready to burst 
through its delicate shroud. This generally happens in 
early morning, and is a sight to be remembered. After 
brushing each organ, and pluming each wonderful hair, 
the bee is ready for its virgin flight. Occasionally the bees 
are matured some time before they emerge in June. 

It is a remarkable fact that the eggs laid first in the 
lower cells produce females, which take some days longer 



May 2, 1898.] 



KNOWLEDGE. 



99 



to reach maturity than do the males, which are always 
produced from the eggs laid last in the cells nearest to the 
entrance of the burrow. This egg laid last is matured 
first, and the bee (a male), excavating its way into the open 
air, leaves its cell empty, so that the bee below it can then 
eat its way through the cap of leaves and pass out through 
the empty cell (Fig 21). The third bee does the same, and 




Fig. 21.— Section of Cells and Puddings. 

ao on until the last bee (the egg of which was laid first) 
is enabled to pass through the whole of the other cells 
until she reaches the open air. 

The peculiar bee the sole representative in this country 
of the genus Anthidium is fond of taking to any old hole 
in a post or tree. It has the habit of collecting the woolly 
tomeutum from the stems of the hollyhock. The bee 
runs up the stem and quickly divests it of its covering, 
which it heaps up into a ball and holds between the legs 
and mandibles. This material is used in the formation of 
its cells. I used to take this bee plentifully in my garden 
near Finsbury Park some twenty years ago, when houses 
and smoke were not quite so plentiful as now. The male 
is very much larger than the female, and has its abdomen 
terminated by an armature of strong spikes. 

Two small bees constitute the genus Chelostoma — the 
larger one, C. jhrisminn', being particularly fond of the 
flowers of mignonette, wild and cultivated ; while the 
smaller, C. campanulai-tim , is plentiful in the delicate hare- 
bell. 

The bees forming the genera Heriades and Ceratina are 




both strangers to me. The records of the capture of 
Heriades are somewhat doubtful. Naturalists cannot be 
too exact in such matters. 

Eiifera longicornis is the only one of the genus and is a 
very beautiful bee. The male has immensely long antennas 
that reach right over and beyond the tail when the bee is 
flying. A large colony used to exist in the bank bounding 
the horse exercise ground near the Vale of Health at 
Hampstead. It has long ago disappeared — even before I 
commenced to work this locality. At Woking it was 
tolerably plentiful years ago. In company with this bee I 
generally found its striking parasite — Xnmada sexfasciata. 

Our next bee generally makes itself heard before being 
seen, for of all notes (and all bees have their special ones) 
this is the shrillest. They love the hottest and most 
brilUan sunshine, and they whiz past with lightning-like 



rapidity from flower to flower. The opal eyes of the male 
render it a most beautiful insect. The bank from which I 
used to dig these bees at Woking is, I am pleased to note, 
still in existence. 

We now come to two bees which are also musicians, viz., 
Anthophora return and neeri-orum — the so-called " mason 
bees" of certain localities. On February 19th of this 
year I noticed one of the first-named species basking in 
the sunshine on a wall at Haslemere, while the ground 
was almost an inch deep with snow. This is one of my 
earliest records of this merry bee. At Hampstead there 
still exists a small colony of A. acen-orum, and few prettier 
sights can be seen in April than that of the males sitting 
with outstretched legs at the entrance of their burrows. 
The intermediate legs have very long fringes of black hairs 
arranged in the most exact manner. In various parts of 
Lincolnshire and the south coast these bees absolutely 




Fig. 23.-Pup(E. 

swarm in the mud or mortar between the stones of walls 
and old buildings. The young natives catch the " white- 
nosed " ones, and put them into their handkerchiefs for 
company during school hours ; but even they are wise 
enough not to catch the " black-nosed " ones (the females), 
though they are quite ignorant as to the sex, and why one 
possesses a sting. I once was fortunate in finding a fine 
specimen of the strange beetle, Sitaris, which is a parasite 
of this bee. These bees do not loiter about when on the 
wing, but fly with immense rapidity, coming upon one so 
suddenly that a nervous person is often startled by their 
loud hum. 

Oar very old friends the humble bees and their parasites 
{Psithijrus) are next in order, and so much has been written 
of these " bumblers " that we can only confirm the praise 
bestowed upon the beautiful creatures whose hum is so 
comforting to the tired entomologist. How eagerly do we 
watch for the reappearance of the hybernated females to 
the yellow catkins of the sallow. To these bees the 
farmers of New Zealand owe the fertilization of the clover. 

To the bees comprising the genus Apis every human 
being is more or less indebted, for what should we do 




Fig. 24.— Five Cells ; two vacated. 

without honey or beeswax ? Perhaps better than our 
ancient ancestors, who had not the knowledge which we 
now possess for manufacturing all kinds of things, pure 
and impure. 

Bees have ever been set forth as the emblems of industry, 



100 



KNOWLEDGE 



[Mat 2, 1898. 



and the more we study the habits of the solitary species 
so much more does our wonder and admiration increase. 
When we subject each species to a microscopical examina- 
tion, we find such an endless wealth of beauty of form, 
and marvellous adaptation of every part, that we feel 
utterly at a loss for words wherewith to describe their 
perfection. 

♦ 

A VALLEY ON SAO NICOLAU, CAPE VERDE 
ISLANDS. 

By Boyd Alexander, m.b.o.u. 

ON dropping anchor in Porto Preguiza, the little 
harbour of Sao Nicolau, one seeks in vain for 
cool verdure whereon to look and rest one's eyes. 
Brown, lofty hills, with asute-angled summits, 
chiselled by the rough hand of Vulcan, rise up 
with weary persistency. There are places, however, on 
their lower portions washed over with the filmy green of 
grass, a growth which is quickly eaten over by goats and 
the thousands of locusts that infest the plains. The 
little clouds now and again take pity on these pastures of 
stone ; they come creeping to their relief, but it is often only 
to expire in the attempt about half way down the steep 
slopes. Here and there on the small plains grow scattered 
acacia trees {Acacia alhida). Some are stunted as though 
they had devoted all their lives in trying to obtain a firm 
foothold in the rocky soil, while there are others with backs 
bent double by the strong north wind. 

For the past three years rain has hardly fallen on the 
island, with the result that a famine is pinching the 
inhabitants. 

The maize, the peasants' chief support, will not grow, 
and now they have only to rely upon the tardy arrivals of 
schooners filled with grain from the States. 

From Preguiza a road leads up to the village of Stancha, 
situated in the only fertile valley that the island possesses. 
It is a broad, finely paved road, constructed with great 
skill, and with a careful eye to gradients ; too good by far, 
and, in fact, incongruous, for such an island, where there 
is only donkey and foot traffic. But the Portuguese excel 
in road making. Furthermore, this road is the means of 
employing many of the native women, who would other- 
wise starve during frequent dearths of rain on the island. 
On November 5th we travelled along this road on 
donkeys, and met numbers of women struggling with heavy 
stones upon their heads and sweating from every pore. 
Their work, which lasts from sunrise to dusk, is hard, and 
they earn scarcely enough to keep body and soul together 
— fourpence a day. 

After a good half-hour's ride along the foot of a lofty hill 
range, that increased in height as we journeyed north- 
wards, we commenced to descend a steep and capacious 
valley ; and at the bottom of this great dried-up water- 
course, just where it bends eastward to gain the sea, lay the 
village of Stancha, nestling amongst an abundance of 
tropical growth. Owing to the limited space the houses of 
this little town are closely picked together, the majority 
being nothing better than huts, with walls of rough stone 
pieced and stuck together with mud, and thatched with the 
dried blades of the maize and sugar cane. Id colour the 
huts are a predominant brown, only a shade or two darker 
than the steep sides of the valley. 

There are, however, besides a church, a few houses that 
stand out distinct, by reason of their size, white-plastered 
walls, and red-tiled roofs. One of these, a well-built 
chateau, is on an eminence overlooking Stancha, and 
belongs to Mr. St. Aubyn, an Englishman — and the only 
one on the island. 



Both he and Senhor Antonio Reis, one of the principal 
Portuguese citizens of the place, showed us much kindness, 
supplying us, amongst other necessaries, with bread that 
was almost at famine prices. 

The day after our arrival we arose early and started 
out to investigate the bird life of this large valley. On 
that particular morning an entrancing beauty seemed to 
hold it. 

Coffee bushes clothe many portions of its sides, while 
on the higher ground maize surrounded the scattered huts 
of peasants. Here and there the coffee growth gives way to 
orange trees flourishing in the midst of sugar cane planta- 
tions, bordered in places near a stream's bank with strips 
of fish cane ; while beyond, and overtopping them, are tall 
cocoanut trees. 

AU this mass of foliage forms a fine study in shades of 
green — the deep green of the orange leaf, and that of the 
cocoanut palm a few tones lighter ; then the tender verdure 
of the sugar cane blade ; and, lastly, the delicate bluish 
green of the fish cane. 

The innumerable banana plants, with some of their 
large leaves in shreds, as if deftly torn by many fingers, 
made avenues of the streams, with banks adorned by 
maidenhair ferns hanging in tresses from the rocks. 

Almost the first birds to draw our attention were 
two species of sparrows — the Santiago sparrow {Passer 
jaf/oensis) and the Spanish sparrow {Paxser salicicola). We 
had met with them on the other islands of the archipelago, 
but had come to Sao Nicolau just at the right season to 
find them breeding. 

Since Gould described Passer jagoensis as being peculiar 
to Santiago it has now become well distributed throughout 
the whole group, but it is most numerous on Santiago and 
Maio, where, in the latter island, its numbers are truly 
remarkable. 

This bright plumaged sparrow is not at all particular as 
to where it builds its nest. Where trees are absent, 
hollows underneath boulders or crevices in rocks are chosen 
as nesting sites. In a tree the nest is domed, but when 
in a hollow of the ground it is an open, compact structure, 
and often lined with feathers. 

The eggs are four in number, and, like those of our tree 
sparrow, in each clutch they are fairly uniform in colour, 
with the exception of one, which is invariably lighter than 
the rest. 

As to the Spanish sparrow, it breeds in the tops of the 
cocoanut trees, and for this reason it has received the 
name of the " cocoanut bird " from the natives. 

While on the island of Maio we came across this species 
in vast numbers. 

Small clumps of acacia trees in a vaUey close to the sea 
presented extraordinary spectacles. The upper branches 
were simply crammed with bulky domed nests, hardly a 
fo'bt intervening between each, while musical chirpings 
issuing from a thousand throats tended to enhance the 
remarkable aspect of this sparrow colony. 

Blackcap warblers filled the valley with their singing, 
while now and again a far more mellow song would come 
from a reed warbler ' Calamocichla breiipennis / hidden in 
the depths of some coffee grove. The blackcap (Sylvia 
atracapitlii) is a resident in the island, and breeds in 
November. We found a considerable number of nests — 
all built in the upper boughs of the coffee trees. The eggs 
of only one out of the six perfect clutches we obtained 
approach in any way the common type of our blackcap's ; 
all the others are very light in ground colour, being 
blotched, spotted, and streaked with dark and reddish 
brown and underlying purplish markings — all forming a 
thick zone round the larger ends. 



May 2, 1898.] 



KNOWLEDGE 



101 



Of course we devoted much attention to Calamocichla 
brevipinnis, and secured a fine series of this rare warbler, 
together with a couple of nests containing eggs. This 
species exhibits all the habits of a true reed warbler. 

Though concealed from view, in yonder group of coffee 
bushes there is a pair. Ever and anon the male bird 
tempts his mate with song. First of all the male bird 
begins by uttering a soft, melodious " chou " several times 
in a deliberate and slow manner, and this call is responded 
to in a similar way by the female ; and then the male, as 
if assured of her attention, pours out his string of exquisite 
notes. The first three notes are uttered with marked 
feeling and a pause follows, after which the remaining 
notes are given out in quick succession and in a higher 
key — a pretty, mellow trill being given to the last one. 

This song is not unlike that of our reed warbler {Acroce- 
phalus streperwi), but it is of far finer quality, though not 
so rich in notes. English reed beds are not conducive to 
fine singing. A chilly atmosphere pervades them, while 
the reeds themselves tremble and commence to jostle one 
another at the mere mention of the wind's coming. And 
amid such disturbing influences the reed warbler utters his 
song, which at times becomes discordant and shrill as 
though he were shouting to the reeds to keep quiet. 

But the other reed warbler (C. brcviptiinis) pours out 
his song under peaceful and lethargic influences. The 
leaves hardly as much as stir ; a tropical heat pervades 
the passages of the cofl^ee groves, and imparts to the bird 
just that amount of languor which makes him utter his 
song with soft deliberate feeling, coaxing forth the notes, 
as it were, till they become round and mellow — a song, 
truly, that haunts the memory. 

The nest, figured here, is of a deep cup-shaped form, 




Xest of Calamocichla Irevipennis in a Coffee Tree. 

and bound to two or more of the upper stems of a cofi'ee 
bush or of a young orange tree, and about eight or nine 
feet from the ground. 

Fine strips from the dried-up blades of the maize plant, 
dead grass, and the fibrous rind from the trunk of the 



banana tree compose the body of the nest, while fine 
grass and bents form the lining. 

The eggs, generally three in number, are bluish white, 
spotted and blotched all over (but more thickly at the 
larger ends) with pale brown and purplish brown, with 
underlying blotches of violet grey. 

Their dimensions correspond with those of the round 
form of our reed warbler. 

Round about this valley a species of owl {Strix insulaiis) 
is met with. It is a very beautiful bird, and is closely allied 
to our common bam owl {Stri.r jfammea). A deep fawn 
colour takes the place of the white in the latter, while 
its upper parts are suffused and marked with a rich French 
grey. It is by no means common, and we found it a 
matter of great difficulty to induce the natives to search 
the tops of cocoanut trees, in which these birds generally 
live. They look upon this owl with superstitious fear, 
believing that a wound from its claws never heals. 

On returning home, as we entered the outskirts of 
Stancha, a company of Egyptian vultures arrested our 
attention. They gave us a lazy glance, and then stared 
in the opposite direction. 

In spite of their repulsive habits, one cannot help 
possessing a sneaking regard for these birds with their 
wrinkled faces of the colour of yellowed parchment, for 
one somehow feels that they are old and venerable, and 
have outlived many a human life. 

The birds find plenty of food about Stancha. Every 
morning, as regular as clockwork, they troop towards the 
slaughter-house and then return the same way — only a 
little slower this time — to an old place of rcnile-.nius outside 
the town, where they indulge in siista.-^, now and again to 
awake, to ponder, perhaps, upon what the nature of the 
next " kill " would be in yonder house. 

During the breeding season, which is generally in 
December, they cease to haunt the villages, and betake 
themselves in couples to lofty hill ranges ; and then they 
appear again in the vicinity of dwellings with their young 
as February comes round. 

The Cape Verde Islands are the westernmost range of 
this species. 

Above the heads of the vultures, enjoying a pure atmo- 
sphere, resided a number of ravens (Comts umbrhuis) that 
cawed lustily from time to time. 

It is very interesting to have discovered this raven, with 
the brown head and neck, on Sao Nicolau, as the species 
was considered by ornithologists to have its westernmost 
range in Egypt. 

With another hour gone by the light of a brief twilight 
commenced to creep over the plains and then down into 
the valley, while the distant hills were suffused with a hue 
like the purple bloom on a grape. And then, as twilight 
glided into dusk, the stillness was broken by the locusts, 
who vamped incessant accompaniments to the soft music 
of night. 

DESERTS AND THEIR INHABITANTS. 

By E. LrDEKKEB, b.a., f.r s. 

IP popular errors connected with matters scientific are 
hard to kill, stiU more is this the case when the 
erroneous opinions have been held by scientists 
themselves. The idea that flints and other stones 
grow is, I have good reason to believe, still far from 
extinct among the non-scientific ; and it is not improbable 
that there are persons possessing a more or less intimate 
acquaintanceship with science who still cherish the belief 
that deserts are uninterrupted plains of smooth sand, 
originally deposited at the bottom of the sea, from which 



102 



KNOWLEDGE. 



[May 2, 1898. 



they Lave been raised at a comparatively recent epoch. 
At any rate, there are several valuable books, published 
not very many years ago, in which it is stated in so many 
words that the Sahara represents the bed of an ancient 
sea, which formerly separated Northern Africa from the 
regions to the southward of the tropic. 

As a matter of fact, these opinions with regard to the 
origin and nature of deserts are scarcely, if at all, less 
erroneous than the deeply ingrained popular superstition 
as to the growth of flints and pudding-stones. And a little 
reflection will show that the idea of the loose sands of the 
desert being a marine deposit must necessarily be erroneous. 
Apart from the difficulty of accounting for the accumulation 
of such vast tracts of sand on the marine hypothesis, it 
will be noticed, in the first place, that desert sands are not 
stratified in the manner characteristic of aqueous formations ; 
and, secondly, even supposing they had been so deposited, 
they would almost certainly have been washed away as 
the land rose from beneath the sea. Then, again, we do 
not meet with marine shells in the desert sands, of which 
at least some traces ought to have been left had they been 
marine deposits of comparatively modern age. 

Whether or no the subjacent strata have ever been 
beneath the ocean, it is absolutely certain that the sands 
of all the great deserts of the world have been formed (?i 
situ by the disintegration of the solid rocks on which they 
rest, and have been blown about and rearranged by the action 
of wind alone. All deserts are situated in districts where 
the winds blowing from the ocean's surface have to pass 
over mountains or extensive tracts of land, which drain them 
more or less completely of their load of moisture. Hence, 
in the desert itself, when of the typical kind, little or no 
rain falls, and there is consequently no flow of water to 
wash away the de'luis resulting from the action of the 
atmosphere on the rocks below. 

In other words, as has been well said, desert sands 
correspond in all respects, so far as their mode of origin is 
concerned, to the dust and sand which accumulate on our 
high roads during a dry summer. On our highways, 
indeed, the summer's dust and sand are removed by the 
rains of autumn and winter, only to be renewed the 
following season ; but in a desert no such removal takes 
place, and the amount of sand increases year by year, 
owing to the disintegration of the solid rock exposed here 
and there. 

Only one degree less incorrect than the idea of their 
submarine origin is the notion that deserts consist of 
unbroken tracts of sand. It is true that such tracts in 
certain districts may extend on every side as far as the eye 
can reach, and even much farther; but, sooner or later, 
ridges and bands of pebbles, or of solid rock, will be met 
with cropping up among the sand, while frequently, as in 
the Lybian desert, there are mountain ranges rising to a 
height of several thousand feet above the level of the 
plain. And it is these exposed rocks which form the source 
whence the sand was, and still is, derived. Such moun- 
tains naturally attract wh at moisture may remain in the ' 
air, and in their valleys are found a more or less luxuriant I 
vegetation. Oases, too, where the soil is more or less I 
clayey, occur in most deserts ; and it is in such spots that [ 
animal and vegetable life attains the maximum develop- 
ment possible in the heart of the desert. 

In the most arid and typical part of the Lybian desert 
the sand is blown into large dunes, which are frequently 
flat-topped, and show horizontal bands of partly con- 
solidated rock ; and between these are open valleys, partly 
covered with sand, and partly strewn with blocks of rock 
polished and scored by the sand-blast. In such sand 
wastes the traveller may journey for days without seeing 



signs of vegetation, or hearing the call of a bird or the hum 
of an insect's wing. But even in many of such districts 
it is a mistake to suppose that vegetable and animal life 
is entirely absent throughout the year ; in the western 
Sahara, for instance, showers generally moisten the ground 
two or three times a year, and after each of these a 
short-lived vegetation springs suddenly up, and if no other 
form of animal life is observable, at least a few passing 
birds may be noticed. 

Among the most important and extensive deserts of the 
world we have first the great Sahara, with an approximate 
area of sixteen thousand square miles, nearly connected with 
which is the great desert tract extending through Arabia, 
Syria, Mesopotamia, and Persia. By means of the more or 
less desert tracts of Baluchistan, Sind, and Kuch, this area 
leads on to the great Rajputana desert of India. More 
important is the vast Gobi desert of Mongolia, and other 
parts of Central Asia. In Southern Africa there is the 
great Kalahari desert, of which more anon. In North 
America there is a large desert tract lying east of the 
Rocky Mountains, and including a great part of Sonora ; 
while in the southern half of the New World there is the 
desert of Atacama, on the borders of Peru and Chili. 
Lastly, the whole of the interior of Australia is desert of 
the most arid and typical description. 

But among these, there are deserts and deserts. Tracts 
of the typical barren sandy type are, as already said, 
extensively developed in the Sahara, as they are in the 
Gobi and the Australian deserts. Between such and the 
plains of the African veld there is an almost complete 
transition, so that it is sometimes hard to say whether a 
given tract rightly comes under the designation of a desert 
at all. A case in point is afiforded by the South African 
Kalahari. Although there are endless rolling dunes of 
trackless sand, and rivers are unknown, yet in many places 
there is extensive forest, and alter a rain large tracts 
could scarcely be called a desert at all. Mr. H. A. Bryden, 
for instance, when describing the Kalahari, writes as 
follows : — " And yet, during the brief weeks of rainfall, no 
land can assume a fairer or more tempting aspect. The 
long grasses shoot up green, succulent, and elbow-deep ; 
flowers spangle the veld Ln every direction ; the giraffe 
acacia forests, robed in a fresh dark green, remind one of 
nothing so much as an English deer park ; the bushes 
blossom and flourish ; the air is full of fragrance, and pans 
of water lie upon every side. Another month, and all is 
drought ; the pans are dry again, and travel is full of 
difficulty." During the grassy season herds of springbok 
used to migrate in the old days to the Kalahari, in the 
northern part of which giraffes live the whole year, although 
they must exist without tasting water for months. 

While such a district can scarcely be termed a desert 
in the proper sense of the word, yet its sands have pre- 
cisely the same origin as those of deserts of the typical 
description. 

For sand to accumulate to the depths in which it occurs 
in many parts of the Sahara and the Gobi by the slow 
disintegration of the solid rocks under the action of 
atmospheric agencies, must require an enormous amount of 
time, to be reckoned certainly by thousands, and, for all we 
know, possibly by millions of years. And we accordingly 
arrive at the conclusion that the larger desert tracts must 
not only have existed as land for an incalculable period, 
but also as desert. Hence we can readily understand why 
the animals of Algeria and the rest of Northern Africa 
diSer for the most part from those of that portion of the 
continent lying to the south of the northern tropic, the 
Sahara having for ages acted as an impassable barrier-to 
most if not all. 



May 2, 1898.] 



KNOWLEDGE. 



103 



But if other evidence were requisite, there is another 
reason which would alone suffice to compel us to regard 
deserts as areas of great antiquity. The habitable parts of 
all deserts — and it is diilicult for the inexperienced to 
realize what barren tracts will suffice for the maintenance 
of animal life — are the dwelling places of many animals 
whose colour has become specially modified to the needs 
of their environment. And it will be quite obvious that 
such modifications of colour, especially when they occur in 
animals belonging to many widely sundered groups, cannot 
have taken place suddenly, but must have been due to 
very gradual changes as the particular species adapted 
itself more and more completely to a desert existence. 

To obtain an idea of the type of coloration character- 
istic of the smaller desert animals, the reader cannot do 
better than pay a visit to the Natural History Museum, 
where, in the Central Hall, he will find the lower part of a 
case devoted to the display of a group from the Egyptian 
desert, mounted, so far as possible, according to their 
natural surroundings. He may also turn with advantage 
to the coloured plate of desert finches and larka facing 
page 380 of the third volume of the " Eoyal Natural 
History." 

Among such animals may be mentioned the beautiful 
little rodents respectively known as jerboas and gerbils, 
together with various birds, such as sand grouse, the cream- 
coloured courser, the desert lark, desert finches, and desert 
chat, and also various small snakes and lizards, among 
the latter being the common skink. Although some of 
the birds retain the black wing-quills of their allies, in all 
these creatures the general tone of coloration is extremely 
pale : browns, fawns, russets, olives, greys, with more or 
less of black and pink, being the predominant tones ; and 
how admirably these harmonize with the inanimate sur- 
roundings one glance at the case in the Museum is sufficient 
to demonstrate. Very significant among these are the 
desert finches {Eri/throspi:a), which belong to the brightly 
coloured group of rose-finches ; one of these specially 
modified species ranging from the Canaries through the 
Sahara and Egypt to the Punjab, while the second is an 
inhabitant of the Mongolian desert. 

Among larger animals a considerable number of the 
gazelles are desert dwellers, these including the palest- 
coloured members of the group ; and lions are likewise to 
a great extent inhabitants of deserts — as, indeed, is true of 
tawny and pale-coloured animals in general. 

All the animals above mentioned belong, however, to 
widely spread groups, which are common to the desert 
tracts of both Africa and Asia, and they do not, therefore, 
serve to prove the antiquity of any particular desert, as they 
or their ancestors might have migrated, and probably did 
migrate, from one desert to another. Birds of such groups 
are, of course, even more untrustworthy than mammals, 
owing to their power of flight. And among those referred 
to, some, such as the sand grouse, can scarcely claim to 
be regarded as exclusively desert birds, since they are 
partial to any open sandy plains, like those of the Punjab, 
or even Norfolk. 

The case is, however, very dififerent with certain of the 
larger mammals, a notable instance being afforded by the 
antelopes allied to the South African gemsbok (Oryx). 
All the members of this group are inhabitants of more or 
less sandy open districts, and none range eastwards of 
Arabia, or possibly Bushire. The gemsbok itself, together 
with the beisa of Eastern and North-Eastern Africa, are 
inhabitants of districts which do not, for the most part, 
come under the designation of typical deserts. And we 
accordingly find that they are by no means very pale 
coloured animals, while both are remarkable for the bold 



bands of sable ornamenting their faces and limbs. On the 
borders of the Sahara there occurs, however, a very 
different member of the group— the white oryx (O. leucnnj.r) 
—differing from all the others by its curving horns, and 
likewise by the extreme pallor of its coloration, which is 
mostly dirty white, with pale chestnut on the neck and 
undcr-parts. Obviously, this species has been specially 
modified as reganls coloration for the exigencies of a purely 
desert existence, and as it is also structurally very different 
from all its existing kindred, it must clearly be looked upon 
as a very ancient type, which commenced its adaptation to 
the surroundings of the Sahara ages and ages ago. The 
Arabian desert is the home of another species of oryx 
{(>. Iieatri.r), which, although more nearly allied to the 
East African beisa, is a much smaller and a much paler 
coloured creature. In this case also there would seem 
little doubt that the period when this animal first took to a 
purely desert existence must have been extremely remote. 

But an even more striking instance is afforded by 
another antelope remotely connected with the gemsbok, 
which is an inhabitant of the Sahara and the Arabian 
desert, and is commonly known as the addax. It is an 
isolated creature, with no near relation in the wide world, 
easily to be recognized by its dirty white colour, shaggy 
mane, and long twisted horns. It must have branched off 
at a very remote epoch from the gemsbok stock, and 
affords almost conclusive evidence of the antiquity of the 
deserts it inhabits, since we have no evidence of the 
occurrence of allied extinct species in other countries. 

Some degree of caution is, however, necessary in drawing 
conclusions that ail isolated desert animals have been 
evolved in the precise districts they now inhabit. A case 
in point is afforded by the saiga, a pale-coloured antelope 
without any very near kindred, inhabiting the steppes of 
Eastern Russia and certain parts of Siberia, where it is 
accompanied by the hopping Kirghiz jerboa (Alactaga). 
Now, since fossilized remains of both these very peculiar 
animals have been discovered in the superficial deposits of 
the south-eastern counties of England, it is a fair inference 
that physical conditions similar to those of the steppes 
(which, by the way, are by no means true deserts) 
obtained in that part of our own country at an earlier 
epoch of its history. From their comparatively isolated 
position in the zoological system, as well as from their 
occurrence in the strata referred to, both these desert animals 
evidently indicate very ancient types ; and they accordingly 
serve to show not only that the semi-desert steppe area 
formerly had a much greater western extension than at 
present, but probably also that the existing portion of that 
area dates from a very remote epoch. Hence they confirm 
the idea of the early origin of the present deserts of the 
Old World and their inhabitants. 

It will be gathered from the foregoing that the deserts 
and steppes of Africa and Asia possess a large number of 
animals belonging either to speci(-s which have no very 
near living relatives, or to altogether peculiar genera. In 
the Arizona desert of the Souoran area of North America 
it seems, however, to be the case that its fauna is largely 
composed of animals much more nearly related to those 
inhabiting the prairie or forest lands of the adjacent 
districts, of which, in many cases at any rate, they con- 
stitute mere local races distinguished by their paler and 
more sandy type of coloration. This is well exemplified 
by the mule deer, which in the Rocky Mountains is a 
comparatively dark and richly coloured animal, but be- 
comes markedly paler on the confines of the Arizona desert, 
assuming again a more rich coloration when it reaches the 
humid extremity of the Californian peninsula. Most of 
the North American mammals, indeed, acquire similar 



104 



KNOWLEDGE 



[May 2, 1898. 



pale tints as they reach the Arizona desert tract ; and a 
practised naturalist can pick out with comparative ease 
the specimens coming from this area from those of the 
moister districts. 

It is not easy to obtain information as to the physical 
features of the Arizona desert as compared with the 
Sahara, and especially as to the amount of sand it con- 
tains area for area ; but, judging from the comparatively 
slight modifications which its mammals appear to have 
undergone as compared with those of the more humid 
regions adjacent, it seems not unlikely that these deserts 
are of more modern origin than the Sahara and the Gobi. 

Whether or no it be true in this particular case, it may 
be laid down as a general rule that the greater the amount 
of sand to be found in a desert, and the greater the 
difference between the animals inhabiting that desert from 
those dwelling in the adjacent districts, the greater will be 
the antiquity of the desert itself. In the case of a desert 
forming a complete barrier across a continent, like the 
Sahara, if the animals on one side are quite different from 
those on the other, its antiquity will be conclusively 
demonstrated. If, on the other hand, they are more alike, 
the age of the desert will be proportionately less. 



THE KARKINOKOSM, OR WORLD OF 
CRUSTACEA.-III. 

By the Eev. Thomas R. E. Stebbing, ji 



R.S., F.L.S. 



THE poet aays, " Tell me where is fancy bred." The 
philosopher asks, " Where shall wisdom be found?" 
To the carcinologist it is no less important to 
inquire where he should search for Crustacea. To 
him a comprehensive answer may be given that, 
with one exception, there is no sort of place 
on the garment of the globe where they may 
not be encountered. Like adventures to the 
adventurous, they will meet the expectant 
observer as well in his daily rambles as in his 
most audacious wanderings from Pole to Pole. 

Only in arid deserts the pursuit is at a 
monstrous disadvantage. For almost every 
crustacean specimen might claim a share in 
the sweet singer's epitaph : " Here lies one 
whose name is writ in water." Whether Mam- 
malia have had marine ancestry may be dis- 
puted by the disputatious, but few will care to 
deny that crabfishes and the whole crustacean 
tribe must have begun the business of life in 
the sea. Out of water, and out of salt water, 
the most part cannot sustain life at all. Almost 
all of them are dependent for health and activity 
on an abundant and constant supply of moisture. 
The comparatively small number of terrestrial 
species, by their close affinity to the aquatic 
hordes, show that they themselves must have 
had water-breathing progenitors. Some of them, 
as is well known, make periodical pilgrimages to 
lay their eggs in the ancestral sea. In lakes 
which are evidently upraised and isolated frag- 
ments of the ocean, crustaceans are found the 
counterparts of others which are stUl marine. 

From the general facts of the distribution 
one may beheve that the Crustacea began in 
moderately shallow water, and that they have 
thence spread themselves on the one hand to the shores, 
up the rivers, over plains, valleys, and mountains, and 
on the other hand into all depths and all quarters of the 
widespread sea. Thus, to deal with them efficiently as 



a whole you need a dredge and a trawl, a boat and a 
ship. You need a navy. That such an expression is 
not hyperbolical can easily be proved. For though the 
names of the Racehorsr, the DUcorery, the Vincennes, 
the Samarang, the Astroluhe, and others may be little re- 
membered in connection with the progress of carcinology, 
yet the Luihtniwi, the Porcupine, and the Challenger, 
the Talisman and the Traraillcur, the Blake and the Alba- 
truss, have been made familiar to the present generation 
by popular narratives as well as by volumes of profound 
research. Without entering into rivalry with Homer in 
his famous " Catalogue of the Ships," which is after all 
only a sum in addition, one may make honourable mention 
of the Novara, the Jos/pliine, the Vettor Pisani, the 
Dijmphna, the Willem Barents, the Alert, the Hauch, the 
Buccaneer, the HirondeUe, the Princesse Alice, the Hassler, 
the Caudan, the Investigator, and stUl leave the list 
uncompleted. Some of the vessels, no doubt, have been 
less important for their size than for their services. A full 
enumeration of them, nevertheless, would show a notable 
international fleet. The immediate object of each expedi- 
tion may have been geographical discovery, the sounding 
of depths, the laying of cables, astronomical observations, 
magnetic surveys, or other such trivialities ; but overruling 
destiny employed them all — more or less — in catching 
crustaceans. 

The ocean floor is difficult of access. The ocean surface 
is more easily skimmed from a boat than from a man-of- 
war. But, whether from boat or pier or ledge of rock, the 
sweeping of that surface with a hand-net is productive of 
treasure. It is rich in larval forms of various groups. It 
is thronged with innumerable Entomostraca. For some 
captures the night is the most favourable period. At some 
times and places the abundance of individuals is over- 




yematocarcinus Agassizii (Faxon). Deep-sea Shrimp, taken b_y the Albatross. 
Life size. Upper antenna imperfect. 

whelming. Square miles of ocean may be coloured by the 
blood-red Calani known as " whale-food." To a cetacean, 
with one or two thousand pounds worth of plates of whale- 
bone depending from its cavernous skull, the extravagant 



May 2, 1898.] 



KNOWLEDGE. 



105 



quantity of these Copepoda is not unwelcome. To the 
naturalist the superfluity of this or any other single species 
is distracting. He does not wish the novel or the rare to 
be concealed or entangled amidst the multitudinous. At 
times, however, numbers help to enhance the charm as well 
as the wonder of the scene presented. Especially is this the 
case with the genus of Copepoda called Sapphirina, concern- 
ing which Dana says that nothing can exceed the beauty of 
some of the species, conspicuous in single specimens, but 
still more when they are congregated in abimdance. " On 
account of their extreme brilliancy and rich reflected tints 
they may be seen at great depths on a sunny day, and as 
each becomes visible only when the position is right for 
the observer's eye, the water seems to flash with moving 
gems ; they even rival the richest opal and sapphire, and 
the most brilliant combination of metallic hues." So they 
endear themselves to the observer, and he distinguishes 
the fascinating species as "the belle," " the rainbow," 
" the gem," " the radiant," " the resplendent." 

There was a time when collectors deplored that on board 
a swift ocean steamer they could not ply their favourite 
occupation. That tantalizing era is at an end. As 
explained in recent papers by Giesbrecht* and Herdman,t 
small invertebrates from a few feet below the surface can 




The sea-shore is generally rich in crustaceans. It is 
almost always far richer than might be supposed from a 
casual survey. The common shore crab, by way of 
exception, is an impudent, defiant creature ; but even the 
fighting shore crab is coloured for concealment, lies low by 
preference, and, upon occasion ofi"ered, adopts the policy 
of scuttle. As a rule the crustaceans of the shore don't 
want to fight — at least not with human antagonists. They 
do not court the eye ; they make themselves small. They 
burrow ; they hide under stones, in crevices of rock, in 
folds of seaweed, in neat but unobtrusive tubes, built 
by themselves or borrowed. They mimic surrounding 
objects. They prowl about in the shells of untempting 
molluscs. In captivity some of them change colour ; some 
of them flounder about as if indignant. The prawns and 
shrimps and hoppers make astounding and unexpected 
leaps and bounds — not into the arms of the intellectual 
observer, but in the other direction, in an unappreciative 
sort of way. There are Tanaids and Cumacea so tiny that 
to look for them in the sand which they inhabit is like 
looking for a needle in a pottle of hay. These can be 
obtained by stirring about a spadeful of the shore in a 
bucket of water, and then pouring the water through a 
fine net before the small animals have had time to bixry 



/C-v, 






Last uropod of the Urothoe, 
highly magnified. 





Urothoe brevicornis (Bate). From 

North AVales. 



Second antenna of ffavstorius 
arenarius (Slabber). 



now be easily obtained while the ship is in full career, by 
day or by night, in tempest or in calm. The water which 
is continually being drawn into the vessel to supply tanks 
and baths is simply filtered through nets, which detain the 
desired organisms. Dr. John Murray, Captain Ht-ndorff, 
and Dr. Kiiimer are credited with having been the 
pioneers in this method of retrieving — so facile, so fruitful, 
so inexpensive. Thus far it appears that a large proportion 
of the game which is bagged in this ingenious manner 
consists of Copepoda. How great a hold these and other 
Entomostraca have obtained on all the waters of the 
globe, both fresh and saline, will be cons-idered hereafter 
in connection with notes on their classification. For the 
Copepoda in particular Mr. I, C. Thompson has recently 
called attention to the grand economic service rendered by 
their immense profusion at the mouths of rivers and 
outside harbours. Transmuting the importunate refuse 
of populous towns into their own minute forms of life, 
they in turn become the food of larger marine animals, 
variously adapted to gratify the palate of Lucullus, to 
illumine his banquet, or adorn his person. 

* Abdruclc aus den Zool-jgischen Jahrliicheru, JCeunter Band, 1896. 
tfrom Trans. Liverpool Biol. Soc, Vol. XII., 1897. 



themselves once more in the subsiding sand. The 
ampbipod, Haustoriiis arenariiui, can be obtained in the 
same manner, but also by simple digging, as it is a monster 
half an inch long. It will " scriggle " in the hand, but is 
warranted harmless. O'tfn, Lowevt-r, wlitn taken, it 
morosely or mcdestly folds itself up, unwilling to display 
the beauties which, were it an exotic species, would make 
it a prize. It appears to be little known, though widely 
distributed on the sandy shores of our islands ; and much 
the same may be said of the species of Urothoe and 
Bafhyporeia. 

It should be remembered that the population of the sand 
is in general quite difi'erent from that of the seaweed- 
covered rocks and stones, and this is illustrated in a rather 
remarkable manner by the distinction between the sand- 
hoppers and the shore-hoppers, although the two groups are 
closely related. Of the rock pools it must sutfice to say 
that, in sheltered and unfrequented spots, they are often 
Liliputian gardens of marine zoology, from which many 
interesting crustaceans may be gathered, either by 
examining tufts of weed or by fishing with a fine net. 
Diflerent forms are to be expected, according as the climate 
of the district explored is cold, temperate, or tropical ; but 
some species have an extremely extended and others a very 



106 



KNOWLEDGE 



[May 2, 1898. 




limited distribution. Tiie mangrove swamps of the tropics 
are distinguished by a highly remarkable crustacean fauna. 
The weed of the Sargasso Sea may be regarded as a kind 
of floating shore. It has its own crabs and shrimps. 
Turtles and hairy crabs play the part of floating islands 
to a considerable population, and an anchored buoy is 
often rich in amphipods among its fringing weeds. 

To the general policy of concealment above described 
there are some ex- 
ceptions. On the 
open shore the sessile 
cirripedes called 
Balani make no pre- 
r^ '•iT''^^^^^m tence of hiding. Being 

cemented to the rock, 
they cannot run away 
if they would, and 
they have little reason 
to wish for the power. 
The hermit crab may 
say, like an EngUsh- 
uian, " My house is 
my castle" ; but the 
Balanus is a castle in 
itself. Six rigid in- 
terlocking valves 
make a stout wall 
round about it, and 
the movable valves 
above, through which 
from time to time 

Flaf/iarthriis lloffmannseygii (Braudt). ^'^^ delicate cirri pro- 
From ants' nest, South of England, trude, can be firmly 

closed down at the 
top. Great stretches of coast-margining rocks are coated 
with colonies of these Balani. But there are many 
other situations in which cirripedes occur. Like the 
spider, which impartially fastens its web to the rafter of a 
cottage or the ceiling of an imperial palace, the cirripede 
plants itself on the body of a whale or the carapace of a 
crab, on the iron sides of a merchantman or on a piece of 
pumice. It will cluster in dense masses round an old 
floating bottle, and some of the small species crowd the 
mouth-organs of crab or crawfish, with easy security, 
wuere tbny might seem to be running into the jaws of 
death. The sau3age-like PuchtjhdAla carcini is parasitic on 
the tail part of Can-inus mcEnm, the above-mentioned 
shore crab, and within reach of the claws of its ho.-t. 
Now, if there is one thing more than another about which 
toe sLoie crab is touchy, it is about having its tail part 
drawn away from its breast, except by the intervening 
ma-»s of its own numerous eggs. No doubt the heartless 
Pachtjbdella, brainless impostor though it be, is all the while 
making believe to be the eggs of the deluded shore crab. 
But the afflicting behaviour of parasites is too extensive a 
subject for the end of a chapter. 

Of inland Crustacea there is much to be told, of which 
only a hint or two can here be given. Several of the groups 
are but poorly represented in our own islands. Apart 
from Entomostraca, our fresh waters can boast of a crayfish 
and here and there a prawn, of the isopod Asclluti communiii, 
and of a few Amphipoda in rivulets, lakes, and wells. We 
have nineteen species of terrestrial Isopoda, these wood- 
lice including the small Platyarthrus Ho/mannsrijijii, found 
only in ants' nests — blind, slow moving, white ; and the 
delicate Trkhonim-ius roscjte— nimble, rose-coloured, and 
rare. Exotic species of sessile-eyed crustaceans may 
chance to be found in our botanic gardens as they have 
been in France. But no land crabs are likely to disturb 



our picnics, requiring as in Panama the flourish of a 
cudgel to repress their effrontery. No river crabs ascend 
the summit of Helvellyn to match those found at similar 
heights in Himalayan ricefields. No little mole of a cray- 
fish burrows under our flower beds, as in Tasmania. We 
have no prawns like those of America, which rival the size 
of large lobsters ; or like those of the Ganges, concerning 
which the Asiatic complacently observed to the fastidious 
Englishman, " Prawn eat nigger — nigger eat prawn." No 
hermit crabs on our hills confront the geologist as they. do 
in the West Indies, marching about among the bush in 
large and heavy shells transported from the beach a 
thousand feet below. No Binnis latro, strange hermit 
without a shell, is here seen competing for cocoanuts as in 
the islands of the Pacific. But notwithstanding some 
deficiencies, our position is extraordinarily favourable for 
the study of Crustacea. The extensive seaboard with its 
many sheltered bays and inlets and harbours ; the variety 
of climate from north to south and from summer to 
winter ; the diftering depths of water roimd our coasts ; the 
ebb and flow of tides ; the mud, the sand, the weeds, the 
rocks, the stones of the shores ; the frequent occurrence of 
wooden piles for piers or breakwaters, of buoys and other 
floating objects ; the abimdance of fish and of empty shells, 
severally enable us to accommodate a multitude of 
crustacean species out of proportion to the space our 
islands cover on a map of the world. To become familiar 
with the names and with the nature, with the habitat and 
with the habits, of all these species, will be found a task 
the more inexhaustible the more absorbing the industry 
brought to bear upon it. 



NEBULA AND REGION ROUND y CASSIOPEIyE. 

By Isaac Roberts, d.sc, f.r.s. 

THE photograph covers the region between R.A. 
Oh. lom. and R.A. Oh. 55m. 57s. ; declination 
between 59° :2r and 6F 2' north. Scale — one 
millimetre to twenty-four seconds of arc. 

Co-ordinates of the fiducial stars marked with 
dots for the epoch a.d. 1900. 

star (.) D.M. No. Hi Zone -t-eo" E.A. Oh. 47m. "-Ss. Dec. N.eO"" 3S-9 Mag. 5-0 
„ (..) ., H« „ 59» „ Oh. .50in. 4.V0s. „ 19° 49-3' „ 6-3 

,.(•.) „ 157 „ 6iy „ Oh.olm 161s. ., 60»531' „ 70 

,.(::) ., 161 ,, 50' ,, Ou. 53m. Sr-jj. „ 5a» 5S 3 „ 7'i . 

The photograph was taken with the twenty-inch reflector 
on 1895, October 25th, between sidereal time Oh. 16m. and 
Ih. 46in., with an exposure of the plate during ninety 
minutes. 

On the north following side of / are two nebulae having 
the outlines of cones or fans, with faint nebulosity between 
them, which on the negative can be traced nearly the 
whole distance between one nebula and the other ; the 
apexes of the nebulae are bright, and the brightness 
diminishes gradually into invisibility as it expands outwards 
from the conical ends. The nebula farthest from the 
north is brighter than the other, and both have a cloud- 
like struct'ire, with many stars of between the ninth and 
seventeenth magnitudes involved, apparently, in them. 

The following are the measured position angles and 
distances of the nebulfe. 

Position angle from 7 of the faint star touching the 
apex of the conical end of the northernmost nebula, 
14° 20' 12 ' ; distance from 7 22' 16". Position angle of 
the faint star touching the apex of the other nebula, 
57° 84' 51" ; distance from 7 19' 19". 

A photograph of the region here referred to was taken 
on 1890, January 17th, upon which the two nebuhe were 
faintly, but distinctly, shown ; and I have compared the 



NEBULiE NEAR r CASSIOPEIiE. 

By ISAAC ROBERTS, D.Sc, F.R.S. 
S 




May 2, 1898.] 



KNOWLEDGE 



107 



original negative of that photograph with the one h^re 
depicted, with the result that no obvious chin^e could be 
detected to have taken place, either in the nebulie ihem- 
selves, or in the relative position angles, or distances 
between them and y, or of the surrounding stars. 

An interval of tive and three-quarter years is therefore 
too short to show sensible changes to have taken place in 
these objects. From this it follows that their distances 
from the earth are great ; and we havi' jvt no unqu-ation- 
able evidence to prove that the nebuhe are phy-<ically 
connected with the star y, but their apparent distances 
from the star are not too great for us to entertain the 
possibility of sucli a physical connection. 

The diffused patch of light surrounding y mnst not be 
mistaken for nebulosity ; for it is caused by the strong 
light of the star illummating a part of the earth's atmo- 
sphere afl'ecting the photographic plate during the exposure. 
This atmospheric glare is of the same character as that 
observed in forming halos round the sun, moon, and bright 
stars ; but the possibility of the star having an extended 
coronal light around it should not be omitted from con- 
sideration, for, though it might exist, its structure would 
be masked on the photograph, by the atmospheric glare, 
as effectually as that of the solar corona is masked. 

There are many stars visible on the negative involved 
in the patch of glare, but they cannot be reproduced on 
the photo copies, for the reason that if the glare is printed 
out so also are all the stars that differ but little from it in 
density. 

A dense photo image of the star can be obtained with 
the twenty-inch reflector in a small fraction of a second of 
time ; but an exposure during an hour, or more, is required 
to show the fainter parts of the nebulm, and the faint 
stars, with clearness. 



THE RECENT ECLIPSE. 

By E. Walter Maunder, f.r.a.s. 

THE methods of investigation employed during the 
late eclipse were so numerous, and their general 
success so great, that it seems impossible to give 
any adequate accoimt of the entire campaign in a 
single paper. I have therefore thought it would 
be better if I confined myself to the work on which my 
wife and I were immediately engaged, and I have no 
donbt that the editors will easily be able to arrange for a 
succession of similar papers, contributed by observers 
engaged in other departments. 

My wife and I, when we contemplated going to India 
to take part in the eclipse observations, found ourselves 
confronted by an extremely difficult problem. Our instru- 
mental means were of the very smallest. They consisted 
of a small binocular, one eyepiece of which was fitted 
with a little direct-vision prism, and of a photographic 
camera, the lens of which, though of high quality, had 
but an aperture of one and a half inches, and a focal 
length of nine inches. We could not but compare, with 
something like a feeling of dismay, this almost microscopic 
equipment with the magnificent instruments with which 
the members of the official parties were furnished, or 
which the directors of large observatories had at their 
disposal. We were standing up in line, armed with our 
little flint-headed arrows, whilst our comrades in the 
battle were rejoicing in the possession of Maxims and 
Lee-Metfords. 

Still, after looking the problem round, we concluded that 
it was not one to lose heart over. We saw our way to at 
least trying three lines of work. With the opera-glass and 



prism I intendt-d to ascert-iin the distribution of coroiiiurn 
in the corona, and especially to see if it fhowed the rifts 
and rays whicli form so sirkiog a feature of omnil 
struciure as it ttppears to the ^ye. With the camera, we 
thought that we might try, fir^t, by giving a v ry ioog 
exposure to ob'ain an image of the long cor)n'il streamers, 
and secondly to photograph the corona, if possible, after the 
end of totaliiy. 

All three enterprises appear? d very hizirdons. It was 
exoeediugly doubtful under t le first heid whether, with so 
sm-ill a dispersion, the 1 171 K light would be snffi -.lenily 
stioug to declare itself o^ar the continuous spectrum which 
the corona also gives. Tne atiempt t > secure the long 
extensions was less likely still. Only a week or two 
before we left England Miss Gierke, whose admirable 
judgment and exact insight in astronomical matters have 
deservedly won such wide and general confidence, had 
written : — " . . . the camera, owing to special difficul- 
ties, has not yet been able to pursue them [the coronal 
extensions so far as four solar diameters." (" Concise 
Knowledge Library," Astronomy, p. 268.) And Mr. Albert 
Taylor, in a paper read before the Royal Dublin Society in 
1891 — a paper evidently most carefully thought out and 
in the conclusions of which our own experience led us to 
place great confidence — had laid down that the maximum 
effective exposure for F 15 iu coronal photography was 
thirty seconds — that is to say, for our camera five seconds. 
Such exposures had on former eclipses failed to give any 
great extensions ; indeed, had generally proved less 
effective than shorter exposures, from the cause Mr. Taylor 
so clearly points out — the great brilliance of the sky back- 
ground. WhUat the last item on our programme seemed, 
a fortiori, to be more doubtful still. 

It will be seen that our prospects did not appear too 
brilliant. Nevertheless, we felt strongly that if new fields 
of eclipse work were to be opened up it necessarily involved 
the risk of failuVe in the first experiments, and those first 
experiments might be made as effectively on a very re- 
stricted scale as on a large one. Their success would be 
no less indubitable, their failure far cheaper. 

And we felt that we were justified in undertaking this 
risk. We received absolutely no financial help from 
(lovemment or any other public body, either for our 
equipment or for our personal expenses in our expedi- 
tion, and we were therefore hampered by no restrictions 
whatsoever. 

We had, moreover, groimds for hope. We had made a few 
experiments in the use of the " Sandell " double and triple 
coated plates, and had been convinced that they at least 
offered us a chance over and above that which ordinary 
dry plates afforded. It seemed to us that, by their use in 
conjunction with a slow and prolonged development, it 
might be possible to bring up the faint extensions of the 
corona before the sky glare blotted them out ; whilst in view 
of Prof. Wadsworth's recent papers, the very smallness of 
the scale of our instrument formed an encouragement. 

One difficulty, however, remained. The second item in 
our programme demanded an equatorial and driving clock. 
These we were without, but the Council of the Royal 
Astronomical Society very generously placed at our dis- 
posal the pretty little equatorial and camera bequeathed 
to it by the late Mr. Sidney Waters, f.r.a.s., and met the 
expense of putting it into full working order. 

The camera attached to this equatorial was not suitable 

* The geaerositT of tTo members of the British Astronomical 
Association enabled the iiehpse Committee of that body to undertake 
the expense of insuring the instruments taken out by the members of 
its two expeditions, and we have to thank them for our share iu this 
benefit. 



108 



KNOWLEDGE. 



[May 2, 1898. 



for the special work which we had in contemplation, but 
it eeemed to us that we might make good use of it. It was 
fitted with one of Dallmeyer's telephotographic lenses, and 
had a full aperture of nearly two and a half inches and an 
equivalent focal length of almost eight feet. The mag- 
nifying power employed was therefore very nearly twelve 
diameters. This appeared to us much too high, but the 
definition which we actually obtained justified Mr. Waters 
in his choice of so great a scale, and forms the highest 
possible testimonial to the quality of Mr. Dallmeyer's 
optical work. Our idea was that with the two cameras 
we might obtain a series of photographs, the equivalent 
exposures of which might be arranged so as to form a geo- 
metrical series ranging from the shortest up to Taylor's 



over this one hundred and forty degrees the "coronium" 
ring was perfectly continuous, it was interrupted by no 
rifts, it spread out into no rays. It was traceable to a 
height of between five and six minutes from the moon's limb, 
and corresponded therefore very closely to what to the eye 
appeared to be the brightest inner corona. So far, then, 
"coronium " appears to be pretty evenly distributed round 
the sun, and not to follow the striking and characteristic 
forms which attract such notice in the corona as seen 
directly. 

Our second field of work, the attempt to photograph the 
long coronal streamers, met with a most wonderful success. 
Our two long-exposure plates — four times Taylor's Umit — 
equivalent to one hundred and twenty seconds with F/15 — 




Sun's Equator. 



limit. The common ratio in this case was about four and 
a half, and, taking Taylor's limit as unity, ranged from one 
four-hundredth up to one. We thought this additional 
item would not be devoid of interest, as it seemed to us 
that not a few coronal photographs on former occasions 
had failed to be so successful as they might have been 
through over exposure. 

So much as to our programme ; now as to our results. 

With the prismatic opera-glass, my first sensation, after 
watching the indescribably beautiful changes which the 
spectrum underwent as totality came on, was one of pro- 
found disappointment. The continuous spectrum entirely 
swamped nearly all the bright rings except those of 
hydrogen and hehum ; and the 1474 K ring, either because 
it was fainter on the eastern side than on the western, or 
because my eyes took some time to become attuned to the 
light, was not seen till after the middle of totality. It was 
then detected over an arc of about one hundred and forty 
degrees — that is to say, only in the semicircle round the 
point of third contact, and not over the whole of that, as 
the continuous spectrum was necessarily so bright at its 
two edges as to swamp the bright line spectrum there. Still, 



showed the four principal coronal streamers to a much 
greater distance than ever before. They can be clearly 
and unmistakably followed to distances from the moon's 
centi'e of three, four, four and a half, and six diameters 
respectively. In the case of the great south-west ray we 
believe that we have traced it, though very feebly, under 
suitable illumination, to a much greater distance still, and 
we may have further remarks to make upon its details on 
some future occasion. As it is, however, it is beyond 
challenge that this south-west ray is shown clearly and 
distinctly upon two photographs much further than has 
been the case in any photograph of the corona that has 
ever been taken before. 

Indeed on three photographs. For beside these two long- 
exposure photographs taken on " S an dell " plates (kindly 
developed by Mr. J. T. SandeU himself), a third photo- 
graph taken with one quarter the exposure — practically 
Taylor's limit — an " Ilford extra rapid " plate which we 
developed ourselves, might have claimed, had it not been 
for the two " SandeU '' plates, to have given the record 
coronal extension. 

The orientation of these three plates is given with great 



May 2, 1898.1 



KNOWLEDGE. 



109 



precision by the presence upon them of Venus, which 
burned like a lamp some six degrees away from the sun. 
The plates were amply large enough to take in the planet, 
since they were sixteen centimetres square ; and the focal 
length of the lens being nine inches, six and one-third 
degrees correspond to an inch, and the solar diameter is 
almost exactly one-twelfth of an inch. 

We learn at once by this means that the great south- 
west ray, so far from coinciding with the sun's equator, 
lay in thirty-five degrees south latitude. The two rays 
which composed the " fishtail " on the eastern side of the 
sun, lay some twenty-four degrees north and south of the 
equator respectively, the equator itself therefore being 
void of any great streamer. 

It will be seen that, in disregarding Taylor's limit, we 
have been abundantly vindicated by the result. Never- 
theless, the considerations Mr. Taylor urged in the paper 
alluded to substantially held good. In developing these 
plates, even the one with only five seconds exposure, the 
general sky glare came up deep and black at an early stage. 
Here we owe our success to the fact that we exposed two 
plates for each given exposure. The companion plate to 
the Ilford five seconds was in itself a comparative failure, 
but its development gave us the experience and courage 
necessary to push the development of its more fortunate 
comrade to a successful conclusion. 

Our last photograph was the most important. Totality 
was over by nearly two minutes when we exposed a plate 
with our little camera for a second and a half. This on 
development yielded us not only the brilliant arc of sun- 
light, but showed an unmistakable coronal ring, for the 
entire dark disc of the moon is seen upon it. 

This success, we may well hope, will have far-reaching 
effects. It is a very long way from realizing that ambition 
of so many astronomers, the photographing the corona 
in full sunlight. But the corona has never before been 
photographed unmistakably and beyond challenge in so 
mucit sunlight. And even should it never lead on to the 
desired goal, something has at least been done to lift large 
partial eclipses from the category of being astronomical 
mere waste material. It will be a distinct advance if in 
future we can fix the 
positions of the roots 
of the great coronal 
rays on such more 
frequent occasions : a 
most necessary advance 
if we are to learn the 
true nature of coronal 
change and motion. 

Our experiments, 
therefore, were success- 
ful beyond our hopes, 
and their success seems 
to justify us in having 
made them. Yet had 
they failed we feel that we should have been not one 
whit less justified. 

But our photographs are on an almost microscopic 
scale, and although sufficient to prove the practicability of 
our methods it is much to be desired that they should be 
repeated on the next occasion with ampler means. We 
feel it incumbent on us, if any way possible, to take part 
in the observation of the next eclipse, that of May 28th, 
1900. ^Ve want to photograph the sun during the entire 
period of the partial phases, to give a considerable range 
of exposures, and to try the efiect of various developments. 
We want, in short, to follow the corona to the utmost 
extent which the sunlight permits. We want also to 




obtain the greatest possible extension of it. We want also 
to give two exposures during totality of much greater 
length than the longest we gave in India. These experi- 
ments we are prepared to carry out with the little camera 
which has just done us such yeoman service, but we 
earnestly hope that we may also be entrusted with in- 
struments that may enable us to duplicate this programme, 
but on a much larger scale. 

The accompanying pictures are reproduced from drawings 
which Mr. W. H. Wesley has most kindly made from the 
original long-exposed photographs. Amongst other details 
of interest Mr. Wesley especially remarks on the cor- 
roboration which these negatives aft'ord of certain well- 
known drawings of the corona. Hitherto there has been 
a wide difference between the corona as presented us on 
the sensitive plate and in drawings even of the most trust- 
worthy observers, and this fact has thrown a good deal of 
doubt upon the value of such drawings. A comparison 
of the corona as here shown with the well-known drawing, 
by Captain Bullock, of the eclipse of 1868, shows a most 
remarkable resemblance between the two. If the two 
were representations of the same eclipse one could not ask 
a more complete correspondence. 



Noti»0 of Boolts. 



A New Astronomy for Bt;iinners. By David P. Todd, 
M.A., PH.D. (The American Book Company, New York. 
1898.) This book deserves an appreciative welcome. It 
is moderate in compass, precise in plan, succinct in treat- 
ment. There is a freshness about it, too, that pleasantly 
reminds one of its origin in a "new" continent. Loci 
commuufs are few : the topics introduced are mostly dis- 
cussed from an original point of view ; students are made 
to feel the i)uranlne<is of them. A " pedagogic purpose" 
is throughout kept in view. The fundamental idea of the 
volume is to teach astronomy as a science of observation — 
to inculcate principles and indicate modes of working 
them out in practice, no matter how roughly, were the 
available equipment " but a yard stick, a pinhole, and the 
rule of three." One recalls — ^be it said without prejudice 
— the system in vogue at Dotheboys Hall of learning 
botany by planting cabbages. For, apart from the 
rigorous sic ros non fohi.s code there enforced, that system 
possesses high excellences and manifold resources, which 
Prof. Todd's sixteen years' experience as a teacher enables 
him to develop to the full. With resourceful ingenuity, 
he makes the " appeal to observation which can alone," 
as Huxley wrote, " give scientific conceptions firmness and 
reality." In the pages before us, precepts are given for 
pursuing a "laboratory course" in the study of the 
heavenly bodies ; the construction of home-made apparatus, 
needing only " moderate mechanical deftness,' is de- 
scribed preferably to the latest refinements of modern 
instrumental methods ; nor can we doubt that its use, 
while flattering the instinctive egotism of beginners, tends 
at the same time to develop in them both mental alacrity 
and manual aptitude. The present author, while rightly 
dwelling upon " the importance of thinking rather than 
memorizing," lets them ofi' with perhaps undue ease from 
the stem necessity of confronting mathematical difficulties. 
Yet we cannot find it in our hearts to quarrel with the 
capital illustration at page 398, where an instantaneous 
photograph of a " foul ball " at cricket replaces a formal 
demonstration that "a projectile's path is a parabola." 
The book is to a most praiseworthy extent "up to date." 
The newest results in every department are included in it — 
included, perhaps, with too slight an allowance of grains 



110 



KNOWLEDGE, 



[May 2, 1898. 



of salt, desirable c«cf((f.s being here and there conspicuously 
absent. We note, however, with satisfaction that the 
author has boldly adopted Schiaparelli's long periods of 
rotation for Mercury and Venus, while withholdin;,' an 
unqualified assent from the hypothesis of "irrigation 
works " on Mars. A few slips and errors might be pointed 
out, but they are in general not very material. The most 
misleading is an attempt to explain stellar variability by 
the direct analogy of sunspots, the actually subsisting 
relation being of the inverse kind. Most of the illustrations 
are new and excellent. Only the coloured frontispiece 
savours of claptrap. 

A Uixtonj of FoH-Uwi. By Rev. H. A. Macpherson, 
.M.A., ji.D.o.u. (Edinburgh : David Douglas.) Illustrated. 
We have in this volume a detailed and exhaustive 
account of the many curious devices by which wild birds 
are or have been captured in different parts of the world. 
The energy, the pains, and the time which the author 
has expended in the compilation of his work may be 
gathered from the fact that his plan has been, as he tells 
us in the introduction, " to read through every ornitho- 
logical work that I could find, in the five or six languages 
which are all that I can personally translate"; besides 
which he has elicited much information by correspondence 
with persons in Japan, China, Borneo, India, AustraUa, 
New Zealand, as well as in many different parts of Europe, 
Africa, and America. 

The result is that we have a book which will long remain 
as a classic upon the subject of past and present fowling 
(exclusive of the use of gunpowder) in every part of the 
world. Comment upon such a book is needless, since it is 
evident at the outset that the author has made himself a 
thorough master of his subject. The book is profusely 
illustrated ; many of the cuts being taken from rare and 
quaint prints and drawings specially prepared from speci- 
mens of traps and devices which the author has procured 
from many parts of the world. The book is printed and 
bound in the sumptuous style generally adopted by Mr. 
David Douglas — a style very well suited for a book of this 
character, but the use of which cannot be too strongly 
condemned for books which should be within reach of the 
purse of every naturalist. 

It is neither our intention nor indeed within our province 
to dictate to anyone as to what he should do or what he 
should not do, but we cannot refrain from expressing our 
regret that so good an ornithologist as the author should 
have employed so much energy and time in a work of this 
character, which does little to advance the science in 
which he is so prominent and devoted a labourer. 

What ix Life.' or. Where are lee .' KViat are ive .' Whence 
did iir come .' mid Whither do ue go ! By Frederick Hoven- 
den. (Chapman & Hall.) 6s. As the majority of people 
are rightly impressed with the complexity of the experiences 
and functions which are collectively referred to as " life," 
Mr. Hovenden's well-meaning efforts to reduce this com- 
plex expression to its simplest terms may, by those who 
judge books by their titles, be considered deserving of 
encouragement. An examination of the prolix argument, 
and perusal of the large amount of irrelevant matter con- 
tained in this volume, will, however, soon convince the 
reader that there are many things both in life and in 
Mr. Hovenden's explanations of it quite beyond com- 
prehension. 

The book, which comprises two hundred and eighty-four 
pages, is divided into three parts. The first of these 
consists of a statement of the case in two pages ; the 
second is concerned with what the author calls the 
evidence proving the case ; the third includes the deductions 
which Mr. Hovenden derives from the issue. The " state- 



ment of the case " is a bewildering succession of definitions 
of elementary truths and assertions which challenge 
contradiction. We have no space to multiply instances, 
but the following examples are typic*! of the uneven value 
of these statements : — " 4. Time is the measurement of 
terrestrial motion." "9. AU 'regeneration' arises from 
the influence of the prime factor, the ether, through 
which the inherent properties of the atom or molecule are 
made active. Hence, no ether, no regeneration.'' 

In Part II. Mr. Hovenden succeeds in being interesting 
only when he confines himself to a description of well- 
recognized facts, and forgets Lis special mission. When he 
is possessed by the prophetic spirit he becomes impolite. 
Thus, on page 50 : " The mathematician is so confident that 
his powers are absolute, and he is so dogmatic in his tone, 
that he is unapproachable. He stands alone, a monument 
of his own creation, in his own egotistical greatness. " Or, 
page 53 ; " The public should study and grasp these ideas, 
which transcend the mind of the physicist, for the physicist 
has got into a fossilized condition ; he will not move until 
that rising power, general intelligence, forces him." We 
trust that when this happens it will not mean the publica- 
tion of more books after the nature of the present one. 

We must refer the curious reader to the book for the 
contents of Part III. Mr. Hovenden becomes even more 
pronounced in his language when he speaks of the orthodox 
religious teachers of the time. On page 221, in dealing 
with the story of the fall of man, our author says : " What 
must we say, then, of priests who attempt to fossilize the 
mind within the limits of this grand lie ! — a lie which is 
damned." The italics are Mr. Hovenden's. 

But we must leave this book, which Mr. Hovenden 
describes as his " contribution to the altruism which is to 
commemorate the jubQee of our beloved Queen Victoria," 
and as ■' the result of original experiments, earnest 
thought, of extensive reading, and of help from contem- 
porary workers and thinkers. It is practically the work of 
a lifetime." We can only regret that the work of a life- 
time should not have been better directed and more 
worthily employed. 

The Sun's Place in Nature. By Sir Norman Lockyer, 
K.cB., r.B.s. (Macmillan & Co. London, 1897.) 12s. The 
present work is, in the main, a repubUcation of a series of 
" lectures to working men," given in 1894, at the School 
of Mines, by Sir Norman Lockyer, and which were pub- 
lished in Nature at that time. 

We must at the outset enter our protest against the 
attacks upon one of the most eminent astronomers of the 
age which disfigure so much of the present book. They 
lower science and scientific men in the eyes of the pubUe, 
and they tend to hide from the reader the real value of 
Sir Norman Lockyer's own work. 

For if we could cut out from the present volume these 
unworthy attacks on Sir William Huggins, and the 
author's reiteration of his own infallibility — a good third 
of the book — we should have left a very large amount of 
most valuable scientific material, most of which has been 
the work of Sir Norman Lockyer himself or has been 
gathered under his superintendence. Prof. Lockyer's 
industry in the collection of facts and opinions is great, 
and this book, like the " Chemistry of the Sun " and the 
" Meteoritic Hypothesis," will be very useful as a work of 
reference. 

The chief points dealt with in the work are, in the first 
book, the romantic story of the discovery of terrestrial 
helium ; in the second^ the demonstration that nebuL-e and 
stars are but stages in one and the same evolution ; the 
third book is an attempt to reinforce the meteoritic 
hypothesis from the observations of new stars ; the fourth 



May -2, 1898.] 



KNOWLEDGE 



m 



and final book is a strong argument that we have, amongst 
the stars, oases not only of diminishing but also of rising 
temperature, and incidentally that our sun should be in- 
cluded in the former class. Had the work been confined 
to the setting forth of these four subjects it would have 
demanded a very considerable meed of praise, though Sir 
Norman Lockyer is always too much theory-ridden to be 
quite a safe guide to the student. A further and serious 
drawback to the book is that several of the most important 
diagrams are completely spoiled in the printing. 

The Concise h'nowlethje Astronomy. By Agnes M. Gierke, 
A. Fowler, and -J. Ellard Ciore. (Hutchinson & Co. 
London, 1898.) os. A handbook of astronomy from three 
such writers might well be expected to be one of most 
unusual excellence, and, as a matter of fact, there can be 
no question but that they have produced a very useful 
and interesting volume. And yet, those to whom the 
deservedly high reputations of Miss Gierke and Mr. Gore 
are known, will scarcely avoid a feeling of disappointment. 
This is chieHy due to the untoward conditions under which 
these two gifted writers have had to work. To Miss Gierke 
are assigned two sections of the book — a history of 
astronomy and the section on the solar system. The 
former has been limited to thirty-six pages and has been 
marvellously well done within this contracted compass. 
It is true that it begins only with Hipparchus, omitting 
absolutely all reference to the astronomies of Chaldea and 
early Egypt, and the enforced rapidity of its glance gives 
no opportunity to the author fairly to exercise her research 
or her grace of style. In the third section, on the solar 
system, also entrusted to her. Miss Gierke has an ampler 
space, which she therefore uses to much better effect, but 
which is yet too confined for her subject. And we notice 
in not a few instanses that an unfaltering verdict is given 
on subjects which are still before the court. So doubt, did 
space permit, the evidence for and against would have been 
fairly presented. We may mention as illustrations the 
rotation of Venus and the nature of the zodiacal light. 

Mr. Gore in the fourth section, on the sidereal heavens, 
has brought together a vast amount of important informa- 
tion ; but it is simply a reference book, carefully collated, 
well arranged — not a treatise. 

Mr. Fowler, in section two, on geometrical astronomy 
and astronomical instruments, deserves unqualified praise, 
and has handled bis subject in a clear, straightforward, 
businesslike manner. We may mention the conditions, 
number, and recurrence of eclipses, the " hunter's " and 
" harvest " moons, amongst many others as subjects which 
he has treated with special lucidity. We would only take 
some exception to the title " Geometrical Astronomy " as 
applied to his section, as the term so used is a little apart 
from its ordinary acceptance. 

In conclusion the book is admirably illustrated by five 
fine plates and a number of clear diagrams. Its faults, 
which are few, are almost inseparable from the plan of such 
a handbook ; and as carried out by its three authors the 
book is most thorough, trustworthy, and complete. 



SHORT NOTICES. 

Phiisiof/raphif fur Advanced Students. Bv A. T. Simmons, B.sc. 
(Macmillan.) Illustrated, -ts. 6cl. Intended for students preparing 
for the exaniinations of the Science and Art Department, this book 
is one of the best which we have seen for that purpose. There are 
many others in the field written on similar lines, but in this one a 
large section is devoted to geolosv — a subject which, in the new 
syllabus, has been considerably modified — and in many other respects 
the author has contrived to adapt his subject-matter to the latest 
requirements of that unstable syllabus of physiography which, ever 
since its first inception, has been undergoing a kind of metamorphosis 



that renders all books on the subject of an ephemeral character. 
Hence the never-ending procession of them, which, like Banquo's line 
of kings stretching out to the crack of doom, quickly follow on the 
heels of each other. 

Slementari/ J'hi/sics, Practical and Theoretical. First Year's 
Cour.ie. By John G. Kerr, m.a. (Blackie.) Illustrated. Is. 6d. 
Intended for organized science schools, this book deals with both 
practical and theoretical physics, and includes mechanics and hydro- 
statics for first year students. The treatment of the subjects is con- 
ventional, yet sound. The book will, no doubt, serve as a useful 
lever for the purpose of lifting students over the stile in those for- 
midable examinations of the Science and Art Department. 

We have received from Messrs. George Philip & Son a little book 
entitled '" A Popular Introduction to the Study of the Sun," by George 
Mackenzie Knight, a very young man, who displays a wonderful 
insight into that complex subject — cosmography. Mr. Knight is 
already known as the author of a sliort history of astronomy. The 
work under notice is written in an eminently popular style, and, as 
the production of a young man only twenty years of age, it augurs 
well for the author's future as a man of letters. The book is inscribed 
to tlie late llr. Ranyard, who took a friendly interest in the youthful 
astronomer's earlier work. 

Semarkable Comets. By William Thynne Lynn, b.a.. f.b.s. Sixth 
Edition. (Stanford.) 6d. The present edition of this little brochure 
is brought up to date. All the n ost remarkable comets from the 
earliest times up t3 the present day are here described. A list of 
comets which are expected to return during the next hundred years 
is inserted at the end of the book. 

The Story of the British Coinage. By Gertrude Burford Bawlings. 
(Xewnes.) Illustrated. Is. Our author has presented the history 
of our coinage from the earliest times. Each coin is exactly described, 
and many of them are figured on both the obverse and reverse sides. 
Colonial coins also are included, and photographic reproductions 
given, the whole forming a very complete and handy guide to what 
may be called British numismatics. 



BOOKS RECEIVED. 

William Moon, LL.D., and his Work for the Blind. By John 
Rutherford, m.a. (llodder & Stoughton.) Illustrated, os. 

Cantor Lectures on Gutla-Percha. By Dr. Eugene F. A. Obach, 
F.i.c. (Society of Arts.) 

A Student's Text-Book of Zooloffi/. By Adam Sedgwick, ii.A., 
F.ES. (Sonnenschein.) IDustrated. 18s. 

With Peari/ near the Pole. Bv Eivind Astrup. Translated bv 
H. J. Bull. (C. A. Pearson, Ltd.) ' Ulustrated. 10s. 6d. 

The Free- Trade Movement. By G. Armitage - Smith, M.A. 
(Blackie & Son.) 2s. 6d. 

Viisical Statics. By .Tohn Curwin. \ew Edition. Revised by 
T. F. Harris, B.sc. (Curwin & Sons.) Illustrated. 3s. 6d. 

A Simple Photographic Guide to the Choice of a Photographic 
Lens. By T. R. Dallmeycr. (Dallmeyer, Ltd.) Illustrated. 

Elementarg Chemistrg. First fear's Course. By T. A. Cheetham. 
(Blackie.) Illustrated. Is. 6d. 

Practical Radiography. By A. W. Isenthal and H. Snowden 
Ward. Revised Edition. (Dawbarn is. Ward.) Hlustrated. 23. 6d. 
net. 

Notes on Observations. By Svdney Lupton, si .A. (MacmiUan.) 
3s. 6d. 

Essays on Museums. By Sir William Flower, K.c.B. (Macmillan.) 
Illustrated. 12s net. 

Radiography and the X Rays. By S. R. Bottone. (Whittaker.) 
Illustrated. 3s. 

Meteorological and Magnetic Obser cations. (Stonyhurst College 
Observatory. 1897.) 

The Barometrical Determination of Heights. By F. J. Cordeiro. 
(Spon.) 43. 6d. 

The Process of Creation Discovered. Bv James Dimbar. (Watts 
& Co.) 7s. 6d. 

A Text-Book of Botany. By Drs. Strasburger, Jfoll, Schenck, and 
Schimper. Translated from the German by H. C. Porter, ph.d. 
(Macmillan.) Illustrated. IS3. net. 

What is Science ' By the Duke of Argyll. (David Douglas.) 

Bibliography of the Metals of the Platinum Group. By Jas. Lewis 
Howe. (Smithsonian Miscellaneous Collections.) 

The MammiU, Reptiles, and Fishes ofFsscr. By Henry Laver. 
(Simpkin, Marshall, & Co.) Illustrated. 



112 



KNOWLEDGE 



[May 2, 1898. 



BRITISH 




J0^ 
ORNITHOLOGICAL 



Conducted by Hakey F. Witheeby, f.z.s., m.b.o.u. 

Notes feom Dublin Bay. 

KuFF. — On the 28th of August I obtained a pair of 
Euffs in immature plumage, and also saw another one. 

CuELEw Sandpiper. — On the same daj' I saw large 
flocks of Curlew Sandpipers ; one Hock certainly could 
not have been less than five hundred strong. It passed 
quite close to me, the white upper tail coverts of the 
birds being very conspicuous, thus easily distinguishing 
them from the Dunlin when flying. 

AvocET. — In the beginning of October I saw an Avocet, 
which stayed about the marshes till the last week in the 
month, but I failed to add him to my collection. 

AldinoVakieties of Mistle Thrush, Common Snipe, Wood- 
cock, AND Curlew. — The following is a Ust of the varieties 
which came under my notice last season. 

Mistle Thrush. — October 5th ; bluish white all over, 
showing the markings of the breast and throat. This 
ueems a very persistent variety, as a winter seldom passes 
without two or three specimens coming under my notice. 
This, Uke all the other ones 1 have seen, was greatly 
frayed along the edges of the wings and tail. The owner 
informed me that it had been mobbed by other Mistle 
Thrushes for at least a month during which it was under 
his observation. 

Common Snipe. — October 10th; perfectly white all over, 
eyes dark, bill and feet Hght yellowish brown. Obtained 
in Co. Meath. November 27th ; whole plumage rich buff, 
the usual Snipe markings showing through. One of the 
commonest varieties of this species ; usually get three or 
four in a season. Obtained in Co. Kerry. 

Woodcock.- — December 6th ; whole plumage a beautiful 
buff, with a bluish sheen on wings and tail, bars and 
markings a bright brick red. Beak and legs reddish 
brown. From Co. Tipperary. 

Curlew. — January 4th ; whole plumage white, with 
usual markings showing against the white background ; 
a most striking variety ; bill and feet tan colour. 
Shot by Mr. Young, Brockley Park, Queen's County. — 
E. Williams, 2, Dame Street, Dublin. 

Wafer Pipit (Anihus spipoleita) in Carnarrovshire. — At a 
meeting of the British Ornithologists' Club, held on January 19th, 
Mr. Howard Saunders exhibited an immature example of the Water 
Pipit which had been procured by Mr. Gr. H. Caton Haigh on 
December 3rd, 1897, in Carnarvonshire. 

All contributions to the column, eitJier in tlie way of notes 
or photographs, should be forwarded to Harry F. Witherby, 
at 1, Eliot Place, Blackheath, Kent. 

Note. — The first issue of Knowlkdoe containing British Ornitho- 
logical Notes was that for October, 1897. 



.\t a recent meeting of the Members of the Institution 
of Electrical Engineers, Mr. Robert Hammond explained 
in detail a method by which electrical energy on a large 
scale will, at an early date, be generated and at the 
service of consumers. The cost, it is stated, will be such 
as to bring the electric light within the sphere of all light- 
users, as the distribution can be effected at the rate of 
about three farthings per unit. 

Neptune's diameter, according to a recent determination 
by Prof. Barnard, is 32,900 miles. 

Sections A to K of the British Association at the Bristol 
meeting in September next will be respectively presided 
over by Prof. W. E. Ayrton, f.r.s. ; Prof. Francis R. Japp, 
F.R.s. ; W. H. Huddleston, f.r.s. ; Prof. W. F. R. Weldon, 
F.R.S. ; Dr. J. Bonar ; Sir John Wolfe-Barry, f.b.s. ; H. 
E. W. Brabrook, c.b. ; and Prof. F. O. Bower, f.r.s. Sir 
William Crookes, f.r.s., is the President elect, and he will 
deliver his address on Wednesday evening, 7th September. 
Prof. W. J. Sollas, m.a., f.r.s., and Mr, Herbert Jackson, 
will dehver the two evening discourses. 



The third annual Congress of the South-Eastern Union 
of Scientific Societies, whose President is the Rev. T. E. 
R. Stebbing, will be held at Croydon, on June the 2nd, 
3rd, and 4th. A number of interesting papers are to be 
read and discussed, among the contributors being Mr. J. 
W. Tutt, Mr. C. Dawson, Prof. J. Logan Lobley, Mr. 
Fred. Enoch (on the " Life History of the Tiger Beetle "'), 
and Prof. G. S. Boulger, who will deliver the annual 
address, as President elect, on June 2nd. The hon. 
secretary is G. Abbott, m.b.c.s., 33, Upper Grosvenor Road, 
Tunbridge Wells. ,.. 

As an indication of the interest centred in technical 
education, the vast sum of money raised for the Northamp- 
ton Institute, ClerkenweU, is convincing. On the 18th 
March the Lord Mayor inspected and formally opened 
the buildings, which, together with the equipment, have 
cost upwards of d€80,000. In addition, the land, generously 
given by the late Marquis of Northampton, is estimated 
to be worth not less than £25,000. Dr. Mullineaux 
Walmsley, the Principal, is a man of great experience in 
applied science, and a casual inspection of the programme 
of studies to be carried out under his direction augurs 
well for the artizan classes. Examinations (to youths and 
men of this class) are a bugbear, and it is gratifying to 
note that this institute provides courses of lectures and 
demonstrations for nearly all trade subjects at twopence 
per lecture, without any stipulation as to examination for 
the purpose of grant earning. 



[The Editors do not hold themselves responsible for the opiniong or 
■tatements of correspondents.] 

THE LEVEL OF SUXSPOTS. 
To the Editors of Knowledge. 
Sirs,— The instructive article on " The Level of Sun- 
spots," by the Rev. Arthur East, in your last issue, part of 
which dealt with the probable refraction of the umbra by 
the vapours on the solar surface within the spot cavity (an 
opinion which he has already expressed in a recent paper 
to the British Astronomical Association), is interesting from 
the fact that the late R. A. Proctor had arrived at the 
same idea many years ago. In Proctor's " Old and New 
Astronomy," on page 381, the figure (257) is sufficiently ex- 



Mat 2, 1898.] 



KNOWLEDGE. 



113 



plantltory as embodying this idea ; and on page 382 the 
footnote reads ; — " In Fig. '257 I indicate a way in which 
the width of the penumbra on the side furthest from the 
sun's edge (occasionally equal to the width of the side 



PHOTOGRAPHED 




Ideal Vertiual Secliou of a Sun spot in the earliest stage of its 
deTelopment. 

nearest to the edge) may be explained by the refractive 
action of the vapours within the spot cavity. The lines 
Pp, Uuu, U'u'u', and P'p', are supposed to be lines of sight 
from the earth when the spot is viewed aslant." 

We must, however, thank the Eev. A. East for the beauti- 
ful experimental illustrations of this point. 

From the satisfactory way this theory simplifies many 
of the difficulties connected with spot phenomena, it is 
somewhat surprising that it has not found its way into 
more general favour and recent text-books. 

Wm. Shackleton. 

Royal College of Science, London, 
April 11th, 1898. 



SPECTRA OF 

: HERCULIS. 



o CETI AND 



By the kindness of the Kev. W. Sidgreaves we are enabled 
to give the accompanying reproduction of two beautiful 
photographs of these most interesting stellar spectra, ob- 
tained at the Stonyhurst College Observatory in December 
and February last. The spectra are on the same scale as 
that of Ceti given in the number of Knowledge for March 
(page 61), but are prolonged a little in both directions, 
extending, in the orange, below the D lines ; and the 
reference numbers to the great absorption bands, acciden- 
tally displaced in the earlier reproduction, are here given 
in their proper places. 

The juxtaposition of the two spectra brings out clearly 
their very significant likenesses and differences. Under 
the former head comes the series of great fluted absorption 
bands which forms the distinguishing feature of this 
stellar type. Under the latter may be noticed the greater 
structural detail in the bands of a. Herculis, the presence 
of numerous fine hnes, and the appearance, whether 
actual or a mere contrast effect, as of a very bright line 
to the blue of the sharp edge of the dark bands, especially 
of bands four, five, and six. The spectrum of o Ceti, on 
the other hand, is especially distinguished by its two bright 
lines of hydrogen, y and i. The comparison of the two 
spectra at the places of the three hydrogen lines renders 
more distinct the relationship of these to the rest of the 
spectrum, and emphasizes the remarkable fact of the 
absence of the third line, H/3 ; the line which we should 
have rather expected to show its presence with the greatest 
plainness. — E.W.M. 




7 8 9 



(I) 



(2) 



Photographed Spectra of o Ceti (1), 1897, December, and o Herculis (2), 1898, February. 



X 


A 


A 


1 = 4227. 


4 = 4757. 


7 = 5447 


2 - 4420. 


5 = 4951. 


8 =- 5597 


3 = 4581. 


6 = 6162. 


9 = 5756. 



Stonyhurst College ObserTatory. 



114 



KNOWLEDGE 



[May 2, 1898. 



A BRILLIANT METEOR. 
To the Editors of Knowledge. 

Sirs, — Last night at 10.20 I saw an extremely brilliant 
meteor, ■which appeared a little south and east of Procyon, 
and disappeared quite at the zenith. In spite of the bright 
moonlight it was a very conspicuous object of bluish white 
colour ; its course appeared (perhaps from my point of 
view) to be quite straight, and occupied about five or six 
seconds of time. It seemed simply to " go out " at last, 
without explosion, sparks, or anything else. 

April Cth, 1898. G. Northover Stretton. 

MERCURY. 
To the Editors of Knowledge. 

Sirs, — I think it may possibly interest some of your 
readers to know that I observed Mercury to-night, un- 
assisted, except by a mental knowledge of its R.A. and 
Dec, at the short interval of seven minutes only after 
sunset, from my window at King's Cross. Is not this a 
record for a London view ? It was conveniently observ- 
able until 7.50 P.M., except at infrequent intervals, when 
it was obscured by stray clouds. C. B. Holmes. 

April 12th, 1898. 

P.S. — It was between three and four minutes to seven 
when it first revealed itself. 



NATURE'S FINER FORCES. 

SOME NOTES ON OLD WORK AND NEW 

DEVELOPMENTS. 

By H. Snowden Ward, f.r.p.s., Editor of " The 

Photogram." 

IT is rather difficult to find a title for an entirely new 
subject which is still in its early days of investi- 
gation, and to which its pioneer has given no name, 
it is all the more difficult when three or four un- 
authorized persons have undertaken to christen the 
subject, when its scientific basis is uncertain, and when 
there is a suspicion that it may be closely allied to an 
older class of results which have a recognized title. The 
subject of the Bakerian Lecture before the Royal Society 
this year is extremely interesting, because it opens up a 
field of investigation in which the results are surprising 
and curious, while the methods are so simple and the 
requisites are so cheap that it is possible for anyone to 
take up the work and to carry the results a few stages 
further. 

Dr. W. J. Russell gave his lecture the non-committal 
title of " Experiments on the Action exerted by Certain 
Metals and Other Bodies on a Photographic Plate " ; and 
journalists who have recorded his results have given the 
subject such titles as Scotography (apparently because 
this is the name of a method of teaching the blind to 
write), Vapography (because the phenomena may be the 
result of vapour given off from the metals, etc.), and other 
equally appropriate titles. 

Before dealing with Dr. Russell's observations it may 
be well to recall one or two older phenomena which do 
not seem to have been referred to in the discussion on 
Dr. Russell's lecture, but which may have a distinct con- 
nection with his work. 

A common phenomenon, familiar to students, and even 
to many schoolboys, is the formation of " breath figures " 
upon a mirror, a piece of plate glass, or, better still, a 
polished metallic reflector. On the polished surface, which 
should be cold, lay any small object such as a coin. While 
this is in position breathe on the polished surface. After- 



wards, for days and sometimes even for weeks or months, 
the image of the object may be restored by again breathing 
upon the polished surface ; and this may be done re- 
peatedly, even though the surface be well cleaned and 
polished. 

A possibly kindred efi'ect may be seen on windows to 
the inside of which a printed placard has been affixed. 
Though the printing ink does not touch the glass, it will 
be found, after the placard has been exposed for some time, 
that the window has acquired the property of condensing 
moisture on the parts near the printing ink of the placard 
differently from its condensation on other parts. And 
this property will remain for weeks or months, through 
repeated cleanings of the window. 

In the early forties, M. Moser, of Konigsberg, and 
Robert Hunt, the British investigator on light, reported 
some extremely interesting experiments on the eflects of 
contact between various substances and polished metallic 
plates ; and after long, patient research Hunt attributed the 
results to difference of temperature, and called the process 
Thermography. He even went so far as to anticipate that 
the process might prove more valuable than photography 
when fully developed. 

Hunt, working in the days of the Daguerreotype, when 
the photographic image was developed upon a metalhc 
plate by means of vapours, applied the same method to the 
development of his thermographic images, with the result 
that he got strong and permanent representations of the 
objects laid upon his metallic plates. He found that 
dissimilarity in the objects and the polished plates was 
necessary ; for instance, gold and silver coins gave good 
images on a copper plate, while copper coins did not act on 
copper. He noted further that the mass of the receiving plate 
affected the result, and that better images were made upon 
a large than upon a small sheet of copper. Using various 
pieces of glass, mica, tracing paper, etc., it was found that 
while some of the glasses and the tracing paper gave 
strong images, other glasses made little or no impression, 
and the mica left no trace. It was found that some objects 
of which no trace could be developed with mercury vapour 
gave good images with the vapour of iodine. 

The later experiments bring us nearer to the results 
shown on dry plates by Dr. Russell, for Hunt found that 
objects separated from the metallic plate by air space of 
half an inch, or more, were capable of strongly im- 
pressing it after one night's exposure, and that a deal 
box acted very strongly. Further, that printed paper 
acted on the plate to such an extent that very good copies 
of any printed matter could be made, and it was in this 
direction that Hunt suggested the first practical applica- 
tion of Thermography. 

Another set of observations, received with scorn by most 
of the scientific men of their day, but confirmed in 1883 by 
a committee of the Psychical Research Society, were those 
of Reichenbach, on what he called " odic force," a property 
which he found to emanate from almost aU substances. 
Most of Reichenbaeh's observations were made by means 
of sensitive patients, who stated that they could see 
luminous emanations from various metals, etc. ; and it is 
unfortunate that he did not carry out to a considerable 
extent his experiments with photographic plates — on 
which he did find results after the very few experiments 
made. I mention Reichenbaeh's work because his patience 
in research and verification was enormous, and his book 
(" Researches on the Dynamics of Magnetism") is full of 
reports of very suggestive experiments — researches which 
might now be repeated with lenses and photographic dry 
plates, with, perhaps, good results in the light of the recent 
work of Dr. Russell. 



May 2, 1898. 



KNOWLEDGE. 



115 



Scattered through the pages of the photographic journals 
are many reports of single observartions, and short series of 
experiments on similar lines to those of l>r. Russell, and 
the results have been variously ascribed to heat, to X rays, 
to magnetism, to " dark light," etc. ; but it seems to have 
been left to Dr. Russell to carry out a comprehensive series 
of experiments, and to — in some measure — raise the veil 
■which has hitherto shrouded these phenomena in obscurity. 
i)r. Russell found, incidentally, and in the course of 
experiments for another purpose, that zinc, if placed in 
contact with a photographic dry plate, had some action 
upon it which would enable it to be developed as if it had 
been exposed to light ; and, further, that a similar action 
was exerted by many other metals, by wood, by straw- 
board, by many printed papers (which would leave a clear 
impression of their printed matter), etc., etc. All these 
results he detailed in a paper before the Royal Society 
about a year ago ; and in the meanwhile he has been 
repeating.verifymg, and extendinghis observations, with the 
results which were brought forward in the recent Bakerian 
Lecture. At first the zmc and other materials were placed 
in contact with the photographic plates, and it was found 
that after a week's contact an image could be developed 
which would plainly show such minute marks as scratches 
on the zinc ; that the structure, rings of growth, etc., in a 
section of a pine tree, and even the grain of mahogany 
which had formed part of a piece of furniture, and had 
been practically in darkness for a couple of centuries or 
more, were also plainly visible ; and that not only the 
printing, but also the water-marks and accidental defects 
on certain papers, could be developed on the plates. When 
the objects were placed at a little distance from the dry 
plate (gradually increased to an inch or more) the efifect 
was still produced, but, of course, without any detaQ being 
visible. Not only would the action thus pass through 
an inch or more of air, but it also passed easUy through 
gelatine, celluloid, collodion, and gutta-percha tissue. 
Glass was found to be quite impervious, though, curiously 
enough, glass was pervious to the emanation from some 
of the uranium salts which were tested, and which acted 
very strongly, whether in the dry state or in solution. 
This point is important, since it shows that there are at 
least two classes of emanation ; and other experiments 
point to the possibility of there being several more. 

Amongst the most active metals are zinc, magnesium, 
aluminium, nickel, lead, and bismuth. Cobalt, tin, and 
antimony are less active, while copper and iron are prac- 
tically inert. Strawboard and fresh charcoal act very 
strongly upon the plate, as does copal varnish, even when 
quite dry and hard. In the earlier experiments mercury 
seemed to be one of the most energetic agents, but it had 
since been shown that pure mercury was inactive, and that 
the effects observed were due to zinc and lead contained as 
impurities. 

With zinc, which is one of the most satisfactory subjects 
for experiment, it is found that the action is strongest when 
the face has recently been brightened (as by cleaning with 
emery paper), and that old zinc, which is considerably 
oxidized, has practically no effect upon the plate. 

The possibility of the action being due to what may be 
called latent light was suggested, but Dr. Russell finds that 
the action is the same whether the active substance has 
been recently insulated or has long been k«pt in complete 
darkness. 

The action of temperature is very important, and while 
the necessary exposure for a good impression is usually 
about a week (at a temperature of fifteen degrees Centi- 
grade), an increase of temperature to fifty-five degrees will 
reduce the exposure to a few hours. 



As to the cause of these results Dr. Russell does not 
speak with certainty, but he has made many experiments 
which confirm his idea that the effects are due to vapours 
given off by the objects. On this point a great deal of 
additional work is needed, especially in view of the signifi- 
cant facts that the most volatile metals are not the most 
active ; that some oils and gums (such as turpentine 
and copal) will act strongly, while volatile substances 
like alcohol and ether have no effect ; that the uranium 
salts act strongly through glass ; and that a book printed 
so long ago as IGll still gives a faint impression, while one 
dated 1805 gives a strong impression on the plate. If the 
results are due to a vapour it will be interesting to know the 
conditions under which it can continue to be given off 
through two hundred and fifty years. 

Altogether the field of research is most attractive and 
promising, and the publication of Dr. Russell's results 
should lead very many investigators to take it up. If they 
do, I trust we may have more careful observation and less 
hasty publication than was revealed by many of the 
announcements made soon after the publication of the 
work of Prof. Rontgen. 



BOTANICAL STUDIES.-III. 

JUNGERMANNIA. 

By A. Vaugha>- Jennings, f.l.s., f.g.s. 

OUR last study* dealt with a type of fruit formation 
which is about the most highly developed among 
the lower cellular plants. In ColeochcEte, whUe 
the vegetative part of the plant consisted of a 
simple cell-plate, it was noted that the reproductive 
process was far more specialized than that in the first type, 
ra!(c/(e''-(''/.t It was observed that the egg-cell (or ompher,) 
after fertilization became surrounded by a layer of cells 
developed from adjacent tissues, and also that it subse- 
quently divided into a number of separate bodies (carpo- 
sporrs), each of which could give rise to a new plant Uke the 
parent. 

It is evident that both these modifications of the method 
of reproduction are of great advantage to the chances of 
survival of the plant. Not only is the egg-cell more 
protected in its resting stage, but by dividing into several 
independently living portions the probabihties of preserva- 
tion of the type become vastly increased. Those genera in 
which the liberated carpospores have the greatest activity 
and the best power of resistance are those which will 
survive and multiply. 

In the algie, and certain fungi which are probably their 
degenerate descendants, this seems to be the highest stage 
reached in the evolution of " fruits " and the phenomenon 
of •' alteration of iienenitiom." When we look for the next 
step there is a great break in the series, and one which we 
shall probably never be able to bridge over satisfactorily. 
There seems every reason to suppose that the early stages 
in the evolution of the higher plants resulted from the 
spreading of simple aquatic forms on to the land, their 
attempt to gain a footing there, and to adapt themselves 
to terrestrial conditions. 

What the intermediate stages were there is no evidence 
to show. Delicate cellular plants have practically no 
chance of preservation in the rocks of the earth's crust, 
and geological science can give no help. The only avail- 
able method of Investigation is the study and comparison 
of living forms : their life history, and early stages of 
development. 

* Knowledge, iJarch, 1S98. t Knowledge, January, 1898. 



116 



KNOWLEDGE 



[May 2, 1898. 



There would seem to have been three alternatives open 
to the water plants which invaded the land. In the firstplace 
they might perhaps accommodate themselves to living under 
terrestrial conditions without undergoing much structural 
change. So long as moisture is abundant enough at times, 
a plant can, as it were, learn to do without it at others. 
It can Hve through times of dryness, and complete its 
life history when proper conditions are prevalent. Thus 
the simpler forms of the green and the blue-green algie can 
be found in salt water, in fresh water, and on damp earth, 
trees, or brick walls ; and even such highly developed forms 
as Chrodleptis and Pln/copcltis are distinctively land plants, 
though retaining all their algal characters. One is liable 
to forget that a very thin layer of moisture is suificient in 
proportion to the actual size of these living cells : a con- 
sideration of much importance in connection with the 
reproduction of terrestrial cryptogams. 

Other algal forms seem to have accommodated them- 
selves to earthly life, even under conditions of extreme 
dryness, by entering into a mutual contract with certain 
fungi, and establishing the type of plants we know as 
lichens. This story is a biological romance in itself, but 
for the present outside our line of study. 

The third alternative was the gradual change of the 
structure of the plant, so as to render it more capable of 
existence and propagation imder altered circumstances. 

In this process of accommodation of the plant to new 
conditions it became advantageous to develop parts which 
could penetrate the soil and absorb moisture and partial 
nutriment from it, as well as to raise some parts above the 
original level, to be sure of their reaching the sunlight. 
Thus in time resulted the well-defined distinction of root, 
stem, and leaf, with which we are naturally familiar. 

The simplest of terrestrial plants— using the term for those 
distinctly modified for living on ground, as distinct fi:om 
algffi — are the IJepaticce or Livernorts. They can be found 
everywhere, on damp banks or rocks or tree-trunks, and 
they present a beauty and variety of structure that makes 
them a fascinatmg study to the microscopist. 

There are the wide-spreading lobes of the flat thallus of 
Marchantia and its kin, to be found on moist banks every- 
where ; and in mossy places in the springtime the slender 
leafy branches of the ■hmi/ernuinnias grow and fruit with a 
fresh luxuriance which renders them, in the opinion of 
many, more attractive than their drier and hardier cousins, 
the mosses. It is unfortunate that names of such Teutonic 
clumsiness as Liverwort and Jungermannia should be 
applied to so graceful a group ; but the necessities of 
scientific nomenclature oblige us to retain them. 

So far as the vegetative part of the plant is concerned, 
the different genera do to some extent bridge over the 
space between the mosses above and the algse below. 
Though in Marchantia the thallus has a structure so 
specialized as to show at once how widely it is separated 
from a simple seaweed, there are other forms, like Paccia 
and Anthoceros, in which the thin, green, plate-like thallus 
seems but little different from Coleochate. 

Yet all the forms included in the Hepatic a differ from 
lower plants and agree with all higher crptyogams in the 
fact that the most essential part of the reproductive system 
is an " archegonium." So constant is this organ that the 
liverworts, mosses, ferns, and fern allies are now often 
grouped together under the name "Arclt^goniatce." 

An archegonium is a flask-shaped structure containing 
the oijsphere. Its lower part is an oval chamber in which 
the egg-cell lies, and is prolonged upward into a neck 
composed usually of four columns of cells round a central 
axis. As the egg-ceU becomes mature the cells of the 
central axis degenerate, so that a canal is formed full of 



a mucilaginous material, which projects also at the top of 
the neck. 

The antheridia are little round or oval bodies occurring 
at the bases of the leaves of the same or a separate shoot. 
Their interior cells divide up into numerous minute 
antherozoids (or xpennatozoids) which are capable of swim- 
ming by means of a pair of delicate ciha. They are, of 
course, so minute that even a raindrop is amply sufficient 
to enable them to reach the archegonia. When this 
occurs some of them enter the mucilaginous cap at the 
end of the neck, and, making their way down the canal, 
effect the fertilization of the oosphere. 

Hepatics, then, differ from even the highest of thallo- 
phytes in the fact that the egg-cell is, even before fertiliza- 
tion, contained in a special structure intended not only for 
protection, but also modified to assist in the process of 
fertilization. 

It might be expected that this advance in the preliminary 
stages would be followed by a corresponding elaboration of 
the fruit structure, but such is not the case. In aquatic 
types, such as Coleochate, the resting stage seems to be 
a necessity to the oospore in view of the future free- 
swimming life of the unprotected carpospores. 

In a land plant, on the other hand, the swimming powers 
of the carpospores would be of little use in comparison 
with the far wider distribution attainable by the help of the 
wind. If the spores developed protective coats of their 
own they would be capable of considerable resistance to 
adverse conditions, and this appears correlated with a 
decreasing necessity for a resting stage of the oospore. 

Accordingly, what takes place after fertilization is an 
almost immediate enlargement of the fertilized egg-ceU, 
and its commencing internal division into spores. At the 
same time the cells below it grow down into close con- 
nection with the tissues of the parent plant, forming a 
structure known as the foot. So that the spore-bearing 
generation or Sporophyte adopts the method of remaining 
in connection with its parent plant till it is ready to liberate 
its spores ; instead of, as in the algse, preparing itself to 
keep alive for a time after the parent plant has died down. 
In this way it differentiates itself into a foot which remains 
in connection with the parent tissues, a seta or stalk which 
grows upward, and a globular sporangittm or capsule carried 
at its apex. The whole is thus not a fruit, but almost a 
second or alternative plant dependent on the first. It has 
no roots, leaves, or green colour (chlvrophi/ll), and therefore 
cannot exist as an mdependent plant, but is nevertheless 
on the road to become one.* 

The further stages in the life history differ, of course, 
in different genera, but the main features are remarkably 
uniform throughout the group. 

The neck of the archegonium withers after fertilization 
of the egg-ceU. Its wall enlarges for a time with the 
growth of the oospore, but finally spUts at the top, leaving 
a sheath, termed the laginula, round the base of the up- 
growing sporophyte. 

The tissues of the sporangium itself become differentiated 
into an outer two- layered wall and an inner cell-mass or 
archesporium . It is in the further development of the latter 
that we meet with the most striking difference from the 
corresponding organ in algie, and the most evident modifica- 
tion for terrestrial conditions. The cells divide up into a 
large number of smaller ones, and while some of these 
develop into spores, the remainder change into long sterile 
threads termed elaters. The latter are long filaments 

* In one very interesting group of the Jungermanniacfcc, the 
archegonia are carried in a sac-like structure hanging down from 
the stem, and in some cases this may bury itself in the soil and even 
attempt to root itself. 



May 2, 1898.] 



KNOWLEDGE. 



117 



pointed at the ends, and possess a single or double spiral 
thickening-band. Their elasticity and response to chang- 
ing conditions of moisture and dryness assist very much in 
the dispersal of the ripe spores. 

Both spores and elaters are formed while the capsule is 
still surrounded by its " perianth," and the upgrowth of 
the seta commences later and takes place with great 
rapidity. Finally, when atmospheric conditions are suit- 
able the capsule bursts, and in the -Tundermanniacea 
alwaj's divides into four valves. Spores and elaters are 



wall, when there are two coats, breaks through the outer, 
and the contained protoplasm grows out into a cell-plate or 
a cell-thread {protonona), which then buds out into a new 
plant and develops its own arnhegonia. 

This protonema stage seems to be a " reminiscence " 
of the algal ancestor, but it is curious that it is far less 
evident here than in the true mosses, as will be seen later. 

Meanwhile the parent egg-bearing plant or oophyte may 
still continue to exist, and throw out fresh shoots to bear a 
new generation of archegonia and antheridia. 




A. — The end portion of a shoot of Sardia crenulata, a simple type of the leafy Hepaties. The terminal leaves differ 
from the rest, and form a Perianth, at the base of whieh the reproductive organs are developed. B. — Archegonia of one of the 
leafy Hepaties (Caloiri/um). c. — Antheridia of the same. D. — ilicrascopie section through the apex of a shoot of a similar 
type (Junfjermannia). Two unfertilized Archegonia are shown ; one on each side. In the centre is the young " Sporophyte" 
resulting from the fertilizat on of a third Archegonium. The archegonial wall stUl remains as the Calyptra. with the lower part 
of the neck, but has enlarged with the growth of the Oospore. The latter is already undergoing internal division to form Spores 
and Elaters. E. — The apical portion of a shoot of Nardia, showing an Antheridium and two imfertiiized Archegonia. In the 
centre is the Sporophi/te, consisting of a globidar Sporangium carried up on a Stalk or Seta, and sheathed at the base by the 
remains of the Archegonium. F. — A ripe Sporangium or Capsule of Radula complanata at the moment of dehiscence, showing 
the splitting of the wall into four valves, and the ejection of the numerous Spores mixed witli Elaters. G. — Spores and Klaters 
magnified. (A and E, after Engler; D, after Hofmeister; B and c, after Gobel.) 



thrown out and dispersed together. In some genera a 
number of elaters remain attached at one end to the tips 
of the segments of the capsule, but in the genus which 
forms the subject of our illustration they are all free. It 
is very interesting to note that, while the mosses and ferns 
dispense with this assistance to the liberation of the spores, 
it should occur in such different groups as the liverworts 
and the horsetails. Further, that a similar phenomenon 
is seen in those strange fungi, the ilyxomycetes ; and that 
a somewhat similar mechanism is employed in dispersmg 
the seeds of some flowering plants. 

The spores themselves are small spherical bodies with a 
single or double wall. Under suitable conditions the inner 



If, then, we summarize the results of our study of the 
liverwort, regarding especially the mode of reproduction 
and the interrelationship of the two stages of its Ufe, we 
arrive at some such conclusion as this : — 

When the water alga? tried to Uve on land some of them 
were able to do so with little change of structure and still 
retain their primitive character. Others gradually advanced 
by a specialization of the reproductive process and the 
evolution of archegonia, whether or not accompanied by 
increasing complexity of the thallus. This advantage in 
the life struggle was followed up by the persistence of the 
connection between the fertilized egg-cell, with its resulting 
growths, and the parent plant ; just as the evolution of 



118 



KNOWLEDGE. 



[May 2, 1898. 



mammals haa gone side by side with the progressive 
dependence of the young on the mother. 

At the same time, the formation of spores with a strong 
protective coat became a necessity under the new conditions, 
and the accessory assistance of the elaters became of much 
value in securing the wide dispersal of the spores. 

In the liverworts we have, in fact, an indication of a 
tendency on the part of the spore-bearing generation to 
assert itself as an independent plant. It will be our 
business in our future studies to try to discover what has 
been the result of this tendency, and along what lines it 
has acted. 



NOTES ON COMETS AND METEORS. 

By W. F. Denning, f.b.a.s. 
New Comet. — A bright comet was discovered by Mr. 
C. D. Perrine, of the Lick Observatory, Mount Hamilton, 
on the night of March 19th. The position of the comet 
was at R.A. 319" 39', Dec. 10° 43' N., and it was moving 
rather quickly to the north-east. Its brightness was esti- 
mated as of the seventh magnitude, the diameter of the 
coma was two minutes, and it had a tail about one degree 
in length. Elements were computed by Kistenpart and by 
Hussey and Perrine, from which it appeared that the comet 
had just passed its perihelion, and was receding from the 
sun and earth. From observations between March 19th 
and 31st, Kreutz, of Kiel, gives the following elements : — 
Perihehon passage 1898, March, 17-37558 

Longitude of perihelion ... 310 8 11-7 
Longitude of ascending node 262 33 59-6 

Inclination 72 27 48-1 

Perihehon distance ... 1 -098(3 

The perihelion place of the comet occurred, therefore, at a 
distance of about nine millions of miles outside the orbit of 
the earth. The position of the comet will be as follows : — 

Ephemeris by F. Mijller, for Berlin, Mean Midnight. 

Distance iu 

R.A. Decimation. millions of 

h. ni. s. ° ' miles. Briglitness. 

Mar 4 hi IC -h51 574 177 47 

„■ 8 1 15 -h53 14-7 182 042 

„ 12 1 30 25 -hSi 16-3 188 038 

„ 16 1 57 IS -1-55 2-5 193 0-33 

„ 20 2 17 30 +55 36-6 198 030 

„ 24 2 36 52 -H55 69-9 204 0-27 

., 28 2 .55 20 -h56 14-1 209 0-24 

June 1 3 1.J 49 +56 205 214 022 

.,5 3 2 J 19 +56 20-7 219 20 

„ 9 3 44 51 +56 15-8 224 18 

„ 13 3 .59 25 +56 70 229 'Oie 

On April 80th the comet will be placed three degrees 
south of the star X, Cassiopeiaj (magnitude 3-7). On May 
Cth it will be two degrees south of S Cassiopeiae (magnitude 
4-4), and for a few nights, about May 18th, wiU be very 
near the great star cluster in Perseus. 

Enche's Comet. — This well-known periodical comet will 
pass its perihelion on May 24th, but will not be visible at 
that time, as it is near l Tauri, and only about twenty 
degrees east of the sun. In June the comet will move 
rapidly southwards, and will approach the earth to within 
about twenty-three millions of miles on July 3rd, so that 
it will be a fairly conspicuous object to observers in the 
southern hemisphere. 

Cometdrij ]>iscoveri). — At the last meeting of the British 
Astronomical Association, on March 30th, Mr.Crommellin, 
of the Greenwich Observatory, made some remarks rather 
derogatory to English observers in regard to discoveries 
of comets. His strictures appear to be quite justified by 
the facts, for there is no reason why nearly all the prizes 
in this field should be carried off by Americans. In view 



of the large number of capable observers, it is certainly a 
very remarkable circumstance that so few comets are 
discovered in this country. The climate cannot be blamed 
for it. Either observers do not thoroughly pursue the 
work of sweeping or there mast be something wrong with 
their instruments or methods. The work itself is easy 
and requires no great skill, the chief things essential to 
success being patience and perseverance. But a man's 
individual observational capacity comes in as an important 
factor, for small, faint, and difficult comets would again 
and again elude detection by a poor observer. It is hoped 
that some English amateurs will give their earnest 
attention to this department. They would find it equally 
interesting, and in the end more profitable, than observing 
the moon, planets, and double stars. 

Recent Fip.eb.\lls.. — On March 29th, 8h. 51m., a fine 
slow-moving meteor, not quite as bright as Jupiter, waa 
observed by Mr. A. King, at Leicester. It had the appear- 
ance of a bright green star, followed by a red tail three 
and a half degrees in length. Its path was from 124^" 
+ H° to 97^" — 12°, and duration of flight about equal 
to four and a half seconds. 

On April 4th, lOh. 35m., a very brilliant meteor was 
seen by Mr. J. H. Preston, of Fishponds, near Bristol. 
It fell in a very oblique path from east to west. The 
nucleus appeared to be of the size of a fairly large orange, 
and at the end of its flight it apparently exploded into a 
large number of fragments. 

On April 5th, lOh. 15m., a large meteor, brighter than 
Venus, and with a remarkably slow movement, was 
observed by the Kev. T. E. R. Phillips, at Yeovil. He 
says : " It was of a beautiful golden yellow or orange 
colour, and left a train of sparks behind. One can hardly 
conceive of what its splendour would have been had there 
been no moon. It travelled through a hundred degrees of 
longitude so far as I traced it, and I probably missed the 
beginning and certainly missed the ending, as the meteor 
dropped behind some houses. Owing to the brilliant moon- 
light it was diflicult to determine its position with accuracy. 
I first caught it near i; Leonis, and followed it as far as a 
point a little below S Herculis. The duration of flight was 
twelve to fifteen seconds, and position of the path from 
154° -I- 17° to 260° + 22°." The same object was seen by 
Mr. Vaughan Cornish at Bournemouth. He gives the 
time as lOh. 17m., and says the meteor was quite as bright 
as Venus at her maximum. The nucleus had a sensible 
diameter and a deep yellow colour. It threw off a short 
train. The observed part of the path was very nearly 
vertical, and extended over about twelve degrees, ending 
three degrees to the right of Vega, and about half a degree 
lower than that star. " The finish up of the meteor was 
like that of a burning body being extinguished ; it did not 
end with a burst." Mr. P. M. Ryves, of Stone, Stafford- 
shire, also witnessed the appearance of the meteor, and 
gives the time as lOh. 10m. He describes it as travelling 
from south-west to south-east in a very nearly horizontal 
flight, and with extreme slowness. There wis no train, 
but a fragment behind and in front. The duration was 
from twenty to thirty seconds, but may have been much 
more as he did not see the beginning. The exact path was 
from 151° -9° to 199°-19°. 

From a careful comparison of these observations it 
appears that, when first seen, the meteor was situated at a 
height of eighty-nine miles above a point in the English 
Channel about twenty-five miles south-east of Dartmouth. 
Moving very slowly to the north-east it entered upon the 
English coast near St. Alban's Head ; then, successively 
passing over Bournemouth, Southampton, Alton, and 
Aldershot, it finally disappeared at an elevation of twenty- 



May 2, 1898.] 



KNOWLEDGE 



119 



five miles over a point five miles north-east of Bisley. 
The flight was directed upon an earthpoint at Braintree in 
Essex, and, seen from this district, the object must have 
appeared stationary in the heavens. The whole length of 
its observed flight was one hundred and sixty-two miles, 
and if the time of its duration is considered to have been 
fifteen seconds its velocity must have been only eleven 
miles per second. The radiant point was in Monoceros at 
121°—!^, but it does not correspond with that of any 
known meteoric shower. This fireball was an exceedingly 
interesting one from its brilliant aspect, and long, graceful 
flight, and it is also notable as a typical specimen of the 
very slow-moving and isolated meteors often directed from 
radiants low in the western sky. 



THE FACE OF THE SKY FOR MAY. 

By Herbert S.vdler, f.r.a.s. 

THE minimum period of sunspots has not arrived yet. 
Mercury is a morning star, and is in inferior 
conjunction with the Sun on the 1st. On the 
14th he rises at 3h. 40m. a.m., with a northern 
declination at noon of 10^ 51', and an apparent 
diameter of 11". On the 21st he rises at 3h. 31m. a.m., 
or about half an hour before the Sun, with a northern 
declination of 10^ 42', and an apparent diameter of OV'. 
On the 31st he rises at 8h. 9m. a.m., or about three quarters 
of an hour before the Sun, with a northern declination of 
13" 20', and an apparent diameter of 7^ '. He is at his 
greatest western elongation on the 28th. While visible 
he describes a direct path in Aries, without approaching 
any very bright star very closely. 

Venus is well placed for observation as an evening star. 
On the 1st she sets at 9h. Oca. p.m., or one hour and three 
quarters after the Sun, with a northern declination at noon 
of 20' 21', and an apparent diameter of 10^ . On the 
11th she sets at 9h. 38m. p.m., or about two hours after 
the Sun, with a northern declination of 22 57', and an 
apparent diameter of 11 ', about ninety-three one-hun- 
dredths of the disc being illuminated. On the 21st she 
sets at lOh. 2m. p.m., with a northern declination of 
24^ 25, and an apparent diameter of 11 . On the 31st 
she sets at lOh. 18m. p.m., or about two hours and a 
quarter after the Sun, with a northern declination of 
24^ 44', and an apparent diameter of 111 '. She will be 
occulted by the Moon on the afternoon of the 22nd, the 
disappearance taking place at 6h. 54m. p.m., at an angle 
of 115^ from the vertex, and the reappearance at 7h. 32m. 
P.M., at an angle of 184 ■ from the vertex ; of course, in both 
cases, before sunset. 

Mars is, for the purposes of the amateur, invisible. 

Jupiter is an evening star, and is still very well placed 
for observation, rising on the 1st at 3h. 20m. a.m., with a 
northern declination of 0^ 52', and an apparent equatorial 
diameter of 43". On the 7th he rises at 2h. 54m. p.m., 
with a northern declination of 1° 1', and an apparent 
diameter of 42V'. On the 14th he rises at 2h. 24m. p.m., 
with a northern declination of 1° 8', and an apparent 
diameter of 42". On the 21st he rises at Ih. 56m. p.m., 
with a northern declination of 1° 11', and an apparent 
diameter of 41j". On the 31st he rises at Ih. 15m. p.m., 
with a northern declination of 1" 10', and an apparent 
diameter of 40V'. During the month he describes a retro- 
grade path in Virgo without approaching any naked-eye 
star. 

Saturn is in opposition to the Sun on the 30th, but his 
southern declination is so great as to prevent any satis- 
factory observation of him in these latitudes, and the 
same remarks apply to Uranus. Neptune is invisible. 



There are no well-marked showers of shooting stars 
in May. 

The Moon is full at 6h. 34m. a.m. on the 6th ; enters 
her last quarter at 9h. 36m. p.m. on the 12th ; is new 
at Oh. 58m. p.m. on the 20th ; and enters her first quarter 
at 5h. 14m. p.m. on the 28th. 



C^css Column. 

By C. D. LooooK, b.a. 

Communicationa for this oolomn should be addressed to 
C. D. LococK, Burwash, Sussex, and posted on or before 
the 10th of each month. 

Solution of April Problem. 

(By A. C. Umlauff.) 
Key-move. — 1. Kt to Kt7. 
If 1. ... K to Kt3, 2. Q to K8ch, etc. 

1. . . . Kt to B4, 2. Kt to K5ch, etc. 

1. . . . Any other, 2. Q to K6ch, etc. 
[There seems to be a dual after 1. ... Kt to Kt7 which 
has escaped notice.] 

Correct Solutions received from Alpha, B. Goulding 
Brown, W. de P. Crousaz, Capt. Forde. 

A. C. Chiillenr/er. — Many thanks for the problems, which 
shall appear shortly. Much regret your abstention in the 
other matter. 

PEOBLEMS. 

By P. G. L. F. 

No. 1. 

Blaci (4). 




White mates m two moves. 
No. 2. 

Blacs (6). 




White (3). 

White mates in three moves. 



120 



KNOWLEDGE. 



[Mat 2, 1898. 



CHESS INTELLIGENCE. 



The Cable Match between teams representing the British 
Isles and the United States was played on March 18th and 
19th, an exciting contest resulting, as last year, in a 
victory for the British team by the odd game. It will be 
noticed that the three American players new to these 
contests (at boards Nos. 8, 9, and 10) met with no success. 
Our opponents would, perhaps, as they seem inclined to 
admit, have done better to rely on well-tried players, even 
at the risk of complaints as to the " New York clique." 
The following is the score : — 



Great Britain. 
3. H. Blackbume (London) 
A. Bum (Liverpool) 
H. Caro (London) 
H. E. Atkini (Leicester) 
G. E. H. Belllngham (Dudley) . 

D. Y. MiUs (Edinburgh) 

C. D. Locock (London) 

E. M. Jackson (Loudon) 
Herbert Jacobs (London) 
H. W. Trenchard (London) 



America. 

H. N. PUlsbury (New York) .. 
J. W. Showalter (New York) 
J. H. Barry (Boston) 
E. Hymes (New York) ... 
A. B. Hodges (New York) 

E. Delmar (New York) 

D. G. Baird (New York) 

F. K. Young (Boston) 

A. K. Robinson (Philadelphia) , 
J. A. Gttlbreath (New Orleans).. 



5i 



A brief description of each game is appended. The 
American players had the move at boards 1, 3, 5, 7, and 9. 

No. 1. — Mr. Blackburne, in defending the Queen's 
Gambit, obtained an inferior game, and was compelled to 
give his opponent the advantage of a passed Pawn. After 
many fruitless attempts to utilize his advantage, Mr. 
Pillsbury, most unselfishly playing to the score, gave up 
his best Pawn on the chance of a win. In the end Mr. 
Blackburne was a Pawn ahead, but this was probably 
insufficient to win. 

No. 2. — Mr. Burn obtained a slight advantage in a close 
game, but after nearly all the pieces were exchanged, Mr. 
Showalter made a most brilliant combination out of the 
small material left, the sacrifice of a piece leaving him 
ultimately with two Pawns to the good and a won game. 

No. 8. — Mr. Caro disregarded his opponent's King's side 
advance in a close game, and obtained a (perhaps) winning 
advantage on the Queen's side ; but he overlooked a most 
ingenious saving and winning resource, and was compelled 
to resign. 

No. 4. — Mr. Atkins obtained a slight advantage in a 
French Defence (2. Q to K2), but the sacrifice of a piece 
did not turn out so well as he expected, and he was glad to 
have an opportunity of giving perpetual check. 

No. 5. — Mr. Bellingham, defending the " close Buy 
Lopez," found himself under a violent attack. He defended 
himself with great care and patience, and most of the 
pieces were exchanged ; but the attack came again with 
Q and R on each side, and the Black Pawns could not be 
saved. 

No. 6. — Mr. Mills had not much diflSoulty in disposing 
of the eccentric variation of the French Defence played by 
his opponent. He won the exchange first, and then the 
game, having only to steer clear of a few traps. 

No. 7. — Mr. Locock's Two Knights Defence was promptly 
converted into a Giuoco Pianissimo. Black obtained a 
slight advantage early, but was unable to prevent the 
exchange of all the mmor pieces. White after that should 
have made some desperate attempt to win or lose (a draw 
being useless to his side), but neither side attempted any- 
thing, and the position at the end of the second day was 
practically the same as at the end of the first. 



No. 8. — Mr. Jackson waited until his opponent had 
finished his eccentric development in a French Defence, 
and then proceeded to take vigorous advantage of the 
various flaws in his opponent's position, winning first the 
Queen and two Pawns for Rook and Knight, and after- 
wards what he liked. 

No. 9. — Mr. .Jacobs played P to KB4 in answer to 1. P 
to Q4. His opponent injudiciously exchanged the centre 
Pawns, thereby freeing Black's game for an attack on the 
King's side. Mr. .Jacobs won a Pawn, and the Bishops 
of opposite colours made winning all the easier. The 
actual process chosen was very pretty, Mr. Jacobs sacri- 
ficing the exchange in an end game in order to permanently 
block in his opponent's Rook. 

No. 10. — Mr. Trenchard attacked a little prematurely 
on the King's side in a close game. His opponent weakly 
blocked the Queen's side, and afterwards sacrificed the 
exchange rather unnecessarily. After that Mr. Trenchard 
picked up Pawns till his opponent resigned. 



The Inter-University Match was played at the British 
Chess Club on March 25th. The following is the score : — 



E. G. S. Chnrchill (Magdalen) .. 
E. E. W George (New College) 
A. P. L. Hnlbert (Keble) 



F. Soddy (Merton) 

F. A. Babcock (Wadham) 

L. T. Dodd (Merton) 



Cambridgc. 

C. E. C. Tattersall (Trinity) .. 

L. McLean (King's) 

H. G. Softlaw (Trinity HaU) .. 
A. Potheringham (Emmanuel).. 
A. W. Foster (St. John's) 
K. S. Makower (Trinity)... 
H. K. Cullen (Caius) 



KNOWLEDGE, PUBLISHED MONTHLY. 



Contents ol No. 149 (March). 

PASE 

The Total Solar Echpse, January 
2-2, 1898. By E. Walter Maunder, 
F.K.A.S. (Illustrated) 49 

British Bees.— I, By Fred. Enock, 
F.I..S.. F.E.S., etc. (Illustrated) 50 

The Vinegar Eel. By C. Ains- 
worth Mitchell, B.A., F.l.c 53 

Botanical Studies.— II. Coleo- 
chfiete. By A. Vaughan Jennings, 
F.I..S., F.o.s. (Illustrated) .54 

Cloud Belts. By Wni.Shackleton, 

FKA.S 56 

A New Theory of the MUky Way. 

ByC. Eastou 57 

Letters .- 60 

The Masses and Distances of 

Binary Stars. By J. E. Gore, 

P.R.A.S 62 

Science Not«s 63 

Notices of Books 63 

British Ornithological Notes 66 

Obituary 67 

The Karkinokosm, or World of 

Crustacea. — II. By the Rev. 

Thomas E. E. Stebbing, ma., 

F.R.S., F.L.s. (Illustrated) 67 

Notes on Comets and Meteors. 

By W. F. Denning, f.r.a.s. ... 70 
The Face of the Sky for March. 

By Herbert Sadler, f.r.a.s 71 

Chess Column. By C. D. Locock 71 
Plate.— The Equatorial Cloud-Belt. 



Contents of No. 15a (April). 

PAGE 

Economic Botany. By John E. 
Jackson, a.l.s., etc 73 

The Structure of Ireland. By 
Grenville A. J. Cole, m.b.i.a., 
F.G.S. (Illustrated) 74 

The Sea-Otter and its Extermina- 
tion. By E. Lydekker, ».A., 
F.E.s. (Illustrated) 78 

British Ornithological Notes 80 

Letters 81 

British Bees. — II. By Fred. 
Enock, F.L.s. , F.E.S. , etc. (Illus- 
tra(ed) 82 

In the Moon's Northern Regions. 
By Arthur Mee. F.R.A.a 84 

Notices of Books 85 

Stars having Large Proper Motion. 
By E. C. I-ickering 89 

The Level of Sunspots. By the 
Eev. Arthur East. (Illustrated) 89 

The Evolution of the Venom-Fang. 
By Lionel Jervis. (tHustiated) 91 

Notes on Comets and Meteors. 
By W. F. Denning, F.R.A.S. 94 

The Face of the Sky for April. 
By Herbert Sadler, f.r.a.s 95 

Chess Column. By C. D. Locock 95 

Plate.— The Limar Alps and their 

Neighbourhood. 



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Communications for the Editors and Books for Review should be addressed 
Editors, " Knowibdoe," 326, High Holborn, London, W.C. 



"June 1, 1898.] 



KNOWLEDGE. 



121 






a£N€EJ.lTERATa 



Founded in i88i by RICHARD A. PROCTOR. 



LONDON: JUNE 1, 1898. 



CONTENTS. 



The Mourne Mountains. By trEExviLLE A. J. Cole, 
.U.K. I. A., F.G.s. {Illuxtra(ed) 

The Petroleum Industry. By G-EOEaK T. Hollowat, 
ASSOC. B.c.s. (LOND.), F.i.c. (illustrated) 

Economic Botany. By John E. Jackson, a.l.3., etc. ... 

Weather Accounts. By Alex. B. McD.iwall, m.a. 
(Illustrated) " 

The Prismatic Camera at the Recent Eclipse. By 

J. EVBESHED, F.E.A.S. (Plate) 

Occultation of 26 Arietis observed Photographically. 

By Edward C. Pickeeinq-. (Illustrated) 

Notices of Books 

Shoet "Notices 

Books Received 
Letters ;— Edwin Holmes; W. F. DEXNixa ; G. Abbott, 

II.B.O.S 

Science Notes 

Africa and its Animals. By R. Ltdekker, b.a., f.r.s. ... 
The Vinegar Fly and the Vinegar Mite. By C. Ains- 

WOKTH MiiCHELT., U.A., F.I.C. (Illustrated) 
A Classic Legacy of Agriculture. By John Mills 
Notes on Comets and Meteors. By W. F. Denning, 

F.E.A.S 

The Face of the Sky for June. By Heebeet Sadleh, 

P.E.A.S 

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



136 
130 
137 

139 
140 



143 
143 



THE MOURNE MOUNTAINS. 

By Grenatlle A. J. Cole, m.b.i.a., f.g.s., Professor of 
Geology in the Roijal CoUer/e of Science for Ireland. 

IT is one of the many advantages of a thinly populated 
country that its barren regions are left very much to 
lovers of scenery. The Mourne ^fountains, though 
situated on the easily accessible coast of the county 
of Down, have remained but little visited, even by 
dwellers in Ireland. Despite the admirable introductions 
that have been made to them in recent years,'' the scientific 
observer and the keen pedestrian need have little fear of 
being hampered in their pursuits by the presence of the 
purely casual tourist. 

Those, however, who may not tind it convenient to leave 
the beaten track, can, in a few inspiring drives, complete 

* R. Lloyd Praeger, M.H.r.A., "The Mourne Mountains," Science 
Gossip, new series. Vol. II. (1895), p. 85; and '■ G-uide to County 
Down and the Mourne Mountains," published by the Belfast and 
County Down Railway Company, 1898, with one hundred illustrations, 
price Is. (Marcus Ward & Co.) 



the circuit of the Mournes, and can even cross at one point 
from the western meadows to the sea. The character of 
the mountain group, in all its isolated individuality, can, 
indeed, be best grasped from a preliminary survey of its 
spurs. From Newry, at the head of the long Carlingford 
inlet, we climb to the upland formed by the " Caledonian " 
granite in this district, and presently, across the Silurian 
foot-hills, we see upon our right the grey-green ridges of 
the Mournes. At Hilltown we meet the first road that 
cuts into the silent area, and we gain some notion of the 
steep-sided valleys that lie between these smooth round 
domes. On certain of the nearer summits, little " tors " of 
rock stand out, much as they do on Dartmoor, but on a 
more impressive scale. Then, as we follow the steadily 
rising road, we are cut oii' for a time from distant views ; 
but in four miles the finest of them all bursts on us— 
the seemingly sheer face of Slieve Meel, the grass, as it 
were, sliding away on it and leaving the bare white rock 
exposed ; and beyond, across a romantic bend of the valley, 
the craggy nr.'te of Slieve Bernagh — without question the 
noblest summit of the Mournes. 

And so down, mile after mile, under the wooded slopes 
to Bryansford, where the corner ia turned and we see the 
northern aspect of the highland. Slieve Commedagh and 
Slieve Donard, with a rocky pass between them, dominate 
the landscape here, the latter being the highest mountain 
of them all. Its two thousand seven hundred and ninety- 
six feet bring it, in fact, only a little short of Cader Idris. 

On the east, this compactly arranged highland falls 
steeply to the sea, so that the summit of Slieve Donard is 
only two miles from the actual coast. The splendid road 
is carried, as best it may be, between the heather of the 
moorland and the sea, and crosses at intervals the alluvial 
fans that stream down from the eastern valleys. A pebbly 
raised beach that runs along part of the coast also provides 
a convenient terrace. 

At Bloody Bridge, only two miles south of Newcastle, 
the old roadway, of bitter memory, is seen a little further 
up the glen; and behind it, and stretching high towards the 
notch from which the stream descends, is one of those huge 
cones of detritus that assure one of the reahty of denudation. 
It may have been formed, in the first instance, by a land- 
slide ; but it no doubt was freely added to when the moun- 
tains above were at their highest. Now the stream has 
cut a clear section through it, down to the granite floor, 
and grass has climbed across the slopes of Slieve Donard, 
from which much of the material fell. The outer edge of 
the cone has, moreover, been removed by the sea ; but in 
its remaining mass, and the beauty of its form, it is still an 
admirable picture of a talus-fan, such as may be seen in full 
vitality at the foot of any ravine in Norway, Tyrol, or 
Karinthia. 

At the tiny port of Annalong, we cross one of the larger 
rivers of the Mournes, which rises in a superb steep-sided 
valley under the rock-terraces of Slieve Commedagh. A 
second large stream, the waters of which are about to be 
stored up for Belfast, comes down out of a similar valley 
at Kilkeel ; and soon the road turns westward, passes along 
the beautiful sea-inlet up to Kostrevor, Warrenpoint, and 
Narrow Water, and reaches Newry, where the fifty-mile 
circuit is complete. 

When we examine this moimtain-mass in detail, we find 
that we are not dealing with a range, but with a great 
boss of granite, shaped somewhat like a dumbbell, the 
narrow part being crossed by the road from Hilltown to 
Kilkeel. The principal valleys have been cut far back 
from north or south. The watershed is consequently sinu- 
ous, between the short streams flowing to the Irish Sea 
and the rivers that reach the Atlantic with the Bann ; 



122 



KNOWLEDGE 



[June 1, 1898. 



but it has, when mapped out, a fairly north-east and south- 
west trend. A bold line of summits lies along it, from 
Slieve Meel More to Eagle Mountain ; but their average 
elevation is surpassed by those rising from the wall 
between the Annalong and Kilkeel valleys, beginning 
with Slieve Commedagh (2512 feet), and ending in the 
castellated crags of Slieve Bingian (2449 feet), from 
which a long spur descends southward on Kilkeel. The 
depth of the valleys, in proportion to their width, is one 
of the fine features of the Mournes, and is only fully 
realised by walking along the watershed, and looking down 
over granite cliffs into these veritable grooves, the combes 



According to this view, the domes and valleys of the 
Mourne Mountains have been carved out of an obstacle, 
discovered by the agents of denudation on the side of an 
older ridge. The former covering of Silurian strata is 
actually left to us in a few admirable outliers — a patch 
half a mile across on Thomas Mountain, about half way 
up Slieve Donard ; another on Slievemaganmore, midway 
between Hilltown and Kilkeel, at a height of 1830 
feet ; and another, fifty feet higher, on Finlieve, some 
three miles to the south. It has been stated that 
these fiakes of strata have been floated up on the 
surface of the invading granite ; but the Silurian beds 




Fia. 1. — View in the Valley of tlie lulkeel River, Mourue Mountains, showing cliff, taluses, and distant summits. 

Bernagh is on the right. 



The peak of Slieve 

[R. Wdch, Photo. 



at their heads girt about with crags, and their mouths 
crossed by the blue horizon of the sea. 

The north-and-south trend of the valleys is not due to 
any special structure of the Mournes, for it is one common 
to the district. So constant is it, whether the Mourne 
granite, or the Silurian strata, or the older granite of the 
Newry axis is traversed by the streams, that it probably 
points back to a time when the rocks exposed at the 
surface were more uniform in character, and when a 
highland of Silurian and Ordovician strata concealed the 
Mourne granite altogether. The watershed then may 
have run east and west, and on its surface the streams 
received a uniform trend. As they cut away this surface, 
particularly in the region of their head-waters, they came 
down upon the concealed granite boss, and worked against 
that more slowly. At one point, the streams running 
northward have found no granite as yet beneath them, 
and have notched back the old watershed conspicuously, 
forming the long valley leading over to Kilkeel. 



in situ reach 1940 feet upon Slieve Muck, and 2200 
feet on Shanslieve, north of Slieve Commedagh, and may 
thus easily, at no distant period, have covered the whole 
area of the Mournes. 

Slieve Donard, in that case, would be one of the first 
knobs to protrude through the slates and sandstones as 
denudation had its way ; while the low south-western 
portion of the granite has far more recently come to light. 
The boldness of outline, and the existence of so many 
contrasted domes and peaks (Fig. 1), point equally to the 
modern character of the group. Granite masses readily 
become worn down, in our climate, to round and uniform 
moorlands. On a fine day an observer on the Hill of 
Howth, near Dublin, has only to compare the outlines of 
the old Leinster granite with those of the blue peaks of 

* The geological details are described in Traill, " Explanation to 
Sheets 60 and 71," Geological Survey of Ireland (1878), and Hull, 
" Explanation to Sheets 60, 61, and 71 " (1881) ; but recent advances 
already necessitate some revision. 



June 1, 1898.] 



KNOWLEDGE 



123 



Mourne, some sixty miles north across the sea, to admit 
that the northern group has at least a supremacy of form. 
This is apparent, also, in the details of the landscape, 
as one may come across them in the higher passes of the 
mountains. We have referred to the bold peak-like tors of 
Slieve Bernagh, and to the frequent vertical rock-walls ; but 
the most impressive scene of all is, perhaps, the group of 
granite pinnacles weathered out on the south side of Slieve 
Commedagh. We may come upon these suddenly as the 
mist lifts from the great dome of Donard, leaving the deep 
valleys filled with cloud below us ; and close against us is, 
as it were, a fantastic temple, the columns rising on each 
side of a little gorge. The vertical joints have here had a 
dominant eiiect, while the horizontal ones cut up the 
pinnacles with a fictitious air of masonry. The neigh- 
bouring cliflfa also display the level tabular joints, so 
characteristic of granite, in a remarkable degree, and the 
whole hill-side suggests an acropolis given over to decay. 
The same air of titanic masonry is seen in the analogous 
granite mass of Goatfell in the Isle of Arran. 

This brings us to the petrological characters of the granite 
of the Mournes. While, as in the quarries that scar the 
hills near Annalong, the rock is often coarsely crystalline, 
the general mass is of finer texture, with a ground in which 
the quartz and the alkali-felspar may be intergrown with 
one another. The ferromagnesian constituent is a dark 
mica. Throughout the whole region a drusy structure is 
very common — that is, cavities occur, varying from a 
microscopic size up to four or five inches across, in which 
minerals have developed out freely, with all their proper 
forms (Fig. 2). The orthoclase felspar here appears in dull 
white or yellowish white crystals, as clean and neat as the 
wooden models that are placed before students of miner- 
alogy. The quartz in these cavities is usually a smoky 
variety, forming prisms capped by pyramids, in complete 
contrast to its ordinary mode of occurrence in igneous 
rocks. The mica forms the most exquisite little hexagonal 
tables, standing up on edge ; and, in addition, blue-green 
beryl and colourless topaz are not uncommon, and have been 
much sought for by collectors. One must conceive such a 
rock as having been saturated with liquids under pressure, 
each knot, if we may so say. of the liquid acting as a 
hydi'othermal laboratory — at first delaying crystallisation, 
but finally allowing of free growth, and of the production 
of the most delicate prismatic forms. Few pleasures can 
be greater to the mineralogist than the breaking up of 
these granite blocks in the high passes of the Mournes, and 
the sight of the perfect little crystal-groups, lying there 
fresh as when made, and never before bared to human 
eye. 

The granite of Arran, above referred to, is closely 
similar to that of the Mourne lMountain3,f and we meet 
allied, but less drusy, masses in the heart of Mull and 
Skye. The latter rocks are among the more recent pro- 
ducts of the great period of volcanic activity in the 
Hebrides, which opened in Lower Eocene times. \ Hence 
the peculiar fine-grained granites of Mull and Skye are, 
at the earliest, of Eocene age. 

South of Carlingford Lough there is another granite 
mass, which is intrusive in the dark gabbro of the Carl- 



* See the fine illustratiou in Sir A. Geikie's ■' Ancient Volcanoes of 
Great Britain," Tol. II., p. 419. 

t See Judtl, '' Secondary Rocks of Scotland," Quarterly Journal 
Geological Socief;/, Tol. XXX (1874), p. 275 ; and Teall, " British 
Petrography," pp'. 328 and 330. 

X See J. Starkie Gardner, " Lower Eocene Plant-Beds of Ulster," 
(^arferli/ Jourant Geological Socittii, Tol. XLI. (1885), p. 82, and 
"Leaf-Beas of Ardtun." ibid., Tol. XLIIL, p. 292. 



ingford promontory. The relations of these rocks have 
been admirably described by Prof. Sollas ; and there is 
no doubt as to the correlation of the granite with that of 
the Mourne Mountains. The gabbro is represented on 
the Mourne coast by a multitude of dykes of basaltic 
andesite and basalt, which form a marvellous picture of 
the fracturing to which the Silurian rocks were subjected. 
These dark ribs of igneous rock have altered the Silurian 
shales and sandstones, which appear as a fringe along the 
coast ; but they are cut off abruptly by the granite of the 
adjacent hills. The flakes of Silurian strata that remain 
here and there on the surface of the mountains are 
similarly seamed by dykes ; but the granite cuts off all of 
them, and is clearly later than this first eruptive series. 
A few basic dykes, however, which may be well seen as 
grey-green bands in the granite north of Slieve Bernagh, 
cut through the granite, and represent a return of basaltic 
conditions. Hence we have three igneous series, two being 
basic, with a highly siliceous one between them. 

This is precisely the order of events in the Eocene 
volcanic centres 
of Mull and Skye ; 
and, even in 
microscopic de- 
tails, the rocks of 
the one area may 
be paralleled by 
those of the other. 
Moreover, in the 
county of Antrim, 
the outpouring of 
the sheets of the 
"Lower Basalts" 
was followed by 
local eruptions of 
rhyolite, a highly 
siliceous lava, 
agreeing in com- 
position with the 
granite of the 
Mournes. t This 
series was in turn 
buried by the 
" Upper Basalts." 
All this volcanic 
material in An- 
trim seems to be 
of Eocene age ; 
and the sequence of events practically clinches the argument 
that the Mourne granite belongs also to the Eocene period. 

Here, then, we have a granite, one of those rocks formerly 
supposed to be of very ancient origin, brought near the 
surface as a fluid mass as recently as Cainozoic times, and 
probably not exposed, even in its upper layers, until shortly 
before the glacial epoch. The geological history of the 
Mournes, of Carlingford Mountain, and of the high volcano 
of Slieve Gullion in Armagh, is seemingly, then, a very 
modern matter compared with that of the adjacent Newry 
granite and the old weather-beaten core of Leinster.J 

Possibly the little dome of Ailsa Craig, which has 
suffered so heavily from denudation that its pebbles lie 

* " The Tolcanic District of Carlingford and Slieve Gullion," 
Trans. S. Irish Acad., Tol. XXX. (1894), p. 477. 

t See A. McHenry, "Age of the Trachytic Kocks of Antrim," 
Geol. Mag., 1895, p. 264; also G. Cole," " Rhvolites of Coontv 
Antrim," Sci. Trans. S. Dublin. Soc, Tol. TI. (189d), pp. 84 and 
104. 

t See Knowledqb, Vol. XXI. (1898), p. 76. 




Fig. 2. — Speciuieu of Mourne Granite, 
showing crystals developed in a drusy cavity. 
The pointer, marked T, inilicates a crystal 
of topaz. 



124. 



KNOWLEDGE 



[June 1. 1898. 



scattered by hundreds all down the Irish coast, was a bold 
mass of the same age as the Monrnes and Arran, and 
became almost destroyed by the severities of glacial times. 
In any case, we can now follow out the line along which 
granite intruded in Eocene times, from the south of 
Carhngford Lough to the smooth Red Hills of Skye. Aa 
yet denudation has discovered only the higher knobs, the 
fine-grained and the drusy surface-layers, of the great bar 
of crystalline rock that has here been added to the crust. 
Some day, perhaps, on the rising edge of Europe, the whcfle 
axis may become revealed, worn and rounded into one long 
moorland, extending north and south for two hundred and 
twenty miles. 

Granites of Cainozoio age are naturally seldom met with, 
owing to the depth at which such rocks consolidate. It 
would be interesting to compare with the Mourne granite 
that described by M. Chofifat from Cintra in the west of 
Portugal,* which penetrates Upper .Jurassic strata, and 
which is probably of Eocene age. The granite of Elba is 
actually later than the Eocene ; and, in the elevated 
regions of the Western Alps, which have been severely 
attacked by denudation, the central gaeissic-granice may 
even belong to the Pliocene period. 

We have already! pointed to the great north-and-south 
line, along which materials were erupted in Cainozoic 
times in Western Europe, as being possibly connected 
with the movements that determined our present con- 
tinental edge. Certain it is that the signs of unrest 
spread eastward, and, by the close of the Miocene period, 
the central plateau of France, the brown-coal region of 
Bohemia, the fringe of the Hungarian plain, and the whole 
north-west of Italy, had already become involved. Then 
the great Alpine series of chains rose in their full vigour, 
and the volcanoes of Auvergne, Catalonia, the Eifel, and 
the eastern Ebinelands, piled up the cones that remiin, 
scarcely denuded, at the present day. The Italian region, 
down to the sea between Sicily and Tunis, is still active 
and unstable ; and, when compared with these vigorous 
manifestations, the land of Mourne assumes quite a cold 
and ancient aspect. The great lava-plateaux to the north 
of it were probably broken up and partly submerged by the 
forces that were raising Central Europe;; and the bold 
attempt at western elevation, which allowed of the accent 
of the granite of the Mournes, seems to have ended merely 
in weakening the crust and in enlarging the bounds of the 
Atlantic. 



THE PETROLEUM INDUSTRY. 

By George T. Holloway, assoc. r.c.s. (lond.), f.i.c. 

ALTHOUGH the use of petroleum and its products, 
on what may be called a commercial scale, has 
only arisen within the last forty years, crude 
petroleum has been known and used from the 
earliest times. The " everlasting fire " of the 
Guebers, or fire worshippers of Baku, was fed by natural 
gas — really only the most volatile of the products of crude 
petroleum ; but the most important of the early uses of 
this " rock oil " was for medicinal purposes— mainly skin 
diseases — for which purpose its value is even now recog- 
nized by the medical profession. 



• See De Lapparent, " Traitfe de Geologie," 3me ed., p. 1457. 

t Knowlbdqe, Vol. XX., p. 209 ; also Vol. XXI., p. 77. 

X See the striking remarks of Sir A. Geikie on subsidence between 
the Inner Hebrides and Iceland, in " The Tertiary BasiltPlateaux 
of North-West Europe," Quarterly Journal Qeoloaical Society., Vol. 
LII. (1896), pp. 399-405. 



Numerous references to petroleum occur in the Scriptures, 
and, in the opinion of Lord Playfaur, the " word translated 
as ' salt ' in reference to its loss of savour on exposure, 
should have been rendered ' petroleum,' which, in the air, 
loses its more volatile constituents, and leaves asphalte, 
good only to be ' trodden under foot of men.' " 

Petroleum appears to have been collected and sold at 
Baku, in Russia, and in the Burmese Empire earlier than 
in other districts ; however, its exploitation on a large 
scale may be considered to date from the year 1859, when 
the celebrated " Colonel " Drake, acting on behalf of the 
Pennsylvania Rock Oil Company, sank the first well 
drilled avowedly in pursuit of oil, at Oil Creek in Penn- 
sylvania. The hilarity which the public had previously 
indulged in immediately gave place to the "oil fever" 
when this well was found to yield to the pump twenty-five 
barrels of oil in a single day. Rapid development ensued 
down Oil Creek and along the AUeghany River, so that the 
output of two thousand barrels, each of forty-two American 
gallons, with which 1850 was credited, had risen to five 
hundred thousand barrels in 18G0, and over two million 
barrels in 18G1. Since then the yield has steadily 
increased, almost without any setback, until now the United 
States production amounts to over forty-seven million 
barrels. 

The earher wells yielded their oil only to the pump, but, 
in the summer of 18G1, a well drilled to a deptb of four 
hundred and sixty feet discharged its oil under pressure 
at the rate of three hundred barrels daily. This was 
followed by numerous other flowing or " spouting " wells, 
deUvering, in some cases, as much as three thousand 
barrels daily, thus keenly acsentuating the oil fever, which 
became so intense that the drilhng of a successful well in 
a new district was the signal for a rush of prospectors, 
and, in case of further success, soon gave birth to a sub- 
stantial town, which, when the oilfield became exhausted, 
might vanish as quickly as it had grown up. 

A typical instanca is found in Pithole City, which, about 
nine months after the discovery of oil, in January, 1865, 
had in its vicinity a population of batween twelve and 
sixteen thousand, and, in importance, ranked but little 
below the flourishing town of Pittsburg. Within two years 
of its origin, however, its oil was practically all removed, 
and the founders deserted it in favour of numerous other 
fields which had meanwhile been developed. 

In Russia the petroleum industry is of much greater 
antiquity than in the United States, and oil is said to have 
been exported from that country as early as the tenth 
century. The oil occurs in certain localities in much 
larger quantity than in the States, and is more cheaply 
produced ; indeed, there is no doubt that the Russian 
industry will be flourishing when the American oilfields 
have been practically denuded of their contents, although, 
at present, the business ability, the enormous capital, and 
the perfect organization of the Americans, enable them to 
command the principal markets of the world. 

The " spouting " wells of Russia entirely eclipse those 
of America in output. The first was struck in 1873 by 
the Kalify Company of Biku, and was followed by many 
others, the oil of most of them, as in the case of the 
American oil fountains, being wasted on account of lack of 
storage tanks to receive the sudden and enormous dis- 
charges. The most celebrated oil fountain known, although 
not the largest, was the "Droojba" well, which was struck 
on the 1st of September, 1883, and commenced flowing 
at the rate of about one million eight hundred thousand 
gallons daily, an amount of oil which was valued at eleven 
thousand pounds. The oil rushed from the well in a 
column about eighteen inches in diameter and nearly three 



Jt!NE 1, 1898.] 



KNOWLEDGE. 



125 



hundred feet high, and then fell, forming, together with 
the sand which it had carried up from the well, banks of 
sand enclosing lakes of oil, much of which ran out in a 
broad channel towards the sea. When, after about three 
months, the well was brought under control and capped, 
it was estimated to have yielded between two hundred and 
twenty thoufand and five hundred thousand ton.'< of petro- 
leum, most of which was wasted. Mr. P. Stevens, our 
Consul at Baku, states that early in 1893 a well drilled 
in the district yielded oil at the rate of seventeen thousand 
seven hundred and forty-two tons daily, an amount far in 
excess of that of the Droojba well. Most of this oil also 
was wasted. 

Oil is mainly obtained from the districts already men- 
tioned ; still, petroleum occurs in many countries and in 




Derricks in the Oilfield of Bradford. 

most of the strata comprised between the older Laurentian 
rocks and the newer members of the Tertiaries. In the 
United States the principal deposits lie in Pennsylvania 
and New York (which are generally taken as forming 
one field), and in Western Virginia, Ohio, and Indiana. 
Notwithstanding the new fields that are being opened up, 
the amount of unprospected country is now by no means 
large ; whereas, in Russia, enormous areas of proved 
oil territory, as well as still larger tracts of presumably 
oil-bearing land, are lying fallow because the small areas 
actually imder the drill are capable of more than supplying 
the immediate demand. In Grosnia, and in the Kouban 
and the Crimea, as well as on the Apsheron peninsula, of 
which the oil district of Baku forms a small part, we have, 
for instance, proved tracts of land the output of which is 
likely to be enormous when the exigences of the market 
call for their development. 
Petroleum occurs in commercially workable quantities in 



Canada, Gahcia, Boumania, India, Java, and Sumatra ; also 
in Japan, China, Peru, Germany, and many other countries ; 
and it has been found in several parts of England, though, 
not in sufficient quantity to admit of profitable working. 

Taking the oils of America and Kussia as the most 
important and typical, it is interesting to consider the 
different geological conditions under which they occur. 
The American oil is found in strata of the Silurian and 
Carboniferous epochs, and belongs to what is known as 
the " paraffin " series of compounds ; while that of Russia 
may be referred to the Eocene and Miocene strata of the 
newer Tertiary series, and consists of compounds of the 
" benzene " family. 

The American oil yields on distillation about seventy 
per cent, of kerosene oil suitable for ordinary lamps, 
together with lighter products form- 
ing the various petroleum "spirits," 
heavier oils used in gas manufacture, 
lubricating oils, paraffin wax, vase- 
line, and residuum utilized as liquid 
fuel. The Russian oil, on the other 
band, yields less than half as much 
kerosene and light distillation pro- 
ducts as does the American oil, and 
practically no paraffin, but it gives a 
higher and better yield of lubricating 
oil and a larger proportion of 
residuum, which, under the name 
" astatki," is used as fuel more in 
Russia than in any other country. 

In America, as in all other 
countries, the earlier developments 
were due to the appearance of 
petroleum on the surface of the land, 
4^*, S^^E^St or tD its occurrence in wells sunk for 
S;?*' nSi^^E^HH water or brine ; but now the oil wells 
are very deep, those in the deepest 
drilled district — the Washington dis- 
trict of Western Virginia — averaging 
two thousand four hundred feet. The 
oil occurs mainly in the interstices 
separating the grains of sandstones, 
or between the crystals of a dolomitic 
rock ; and experience has shown that 
it is necessary to raise the oil without 
regard to market requirements, or 
the whole may be pumped up through 
the wells of the neighbouring lease- 
holders, a condition of things which 
has led to a common practice of 
drilling round the boundary of the 
holding before commencing operations elsewhere. 

In Russia, however, the conditions are different ; the 
oO is usually found at comparatively shallow depths, often 
not more than one-fourth of the depth of the American wells. 
A loose sand, consisting of independent grains, comes up 
with the oil, and these grains of sand are a cause of serious 
trouble in the flowing wells on account of their cutting 
action on the caps with which the drillers endeavour to 
close the top of the well-casing to control the outflow. In 
the case of some of these tiowing wells, the blast of sand 
has been known to cut through several thick steel caps 
before the flow could be stopped. The strata in which the 
oil occurs are also so disturbed as to practically constitute 
a large number of independent oil reservoirs, so that closely 
contiguous wells are found to be practically independent 
of each other, and there is no necessity for raising the oil 
until required. 

Had space permitted, it would have been interesting to 



126 



KNOWLEDGE 



[June 1,1898. 



trace the development of the modern drilling plant em- 
ployed for the sinking of the oil wells, from the simple 
hand-worked appliances which, first used in the States 
for the sinking of brine wells, have become gradually 
superseded by the rapid and beautiful drilling plant com- 
prised in what is known as the " American system." This, 
although not the only system in use, will be described as 
representative. 

The first necessity is the "derrick" — a strong wooden 
framing resembling the structure at the pit-head of a 
colliery, and serving to support and control the working 
of the string of drilling tools. The derrick varies in height 
from about thirty feet, in the case of shallow wells, to 
seventy feet, in the case of the deeper wells, and the drilling 
tools are suspended from it on a stout rope, which is operated 
by an engine to raise and lower the tools. Somewhat com- 
plicated in their construction, the drills act by giving a blow 
at the bottom of the boring each time they are allowed to 
descend. A special appliance known as the "jars" is 
arranged to prevent the drill becoming jammed. It con- 
sists of two parts which slide upon each other and give a 
jar to the tool on the up-stroke, so that any tendency to 



"torpedoing" — at the bottom of the well, in order to loosen 
the strata, and so facilitate the oil's access to the well. 
The oil is either pumped, or flows naturally, into a tank, 
from which it is conveyed by pipe lines to the refineries, 
as will be described later on. 





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V\\-\\ after being " torpedoeil." A f^ule Dieeliarj 

jam is overcome. The total weight of a set of drilling 
tools is nearly four thousand pounds, and, in addition to 
this, a series of ingenious tools known as " fishing tools" 
has to be provided for finding and raising any part of the 
drilling tools which may become detached and remain in 
the well. 

At intervals the tools are withdrawn, and the sand pro- 
duced by the drilhng is removed by pumps or balers. 
As the well is sunk it is cased throughout with metal 
tubing to avoid choking up by detritus or caving-in of the 
strata. 

When the oil stratum is struck, or, more usually, when 
the well begins to show a decreased yield, it is common 
in America to explode a charge of dynamite — known as 



ECONOMIC BOTANY. 

By John R. Jackson, a.l.s., etc., Kce/ier of the Mtiseums, 
Roi/al Gardens, Keiv. 

PAPAVERACE/E.— Though this is a comparatively 
small order in the number of genera and species, 
and though the plants themselves are of the nature 
of small herbs, the order is one of considerable 
economic importance and interest. The plants 
are natives of temperate climates, particularly of Europe, 
and are well marked by their narcotic properties. By far 
the most important plant of the family is the opium poppy 
[I'apnvei- sornniferum), which, though it cannot be said to 
be known at the present time in a truly wild state, is 
probably a native of South-Eastern Europe and Asia Minor. 
The poppy has been cultivated from 
early antiquity for the sake of its 
dried juice, well known as opium. 
It is now very widely spread, but 
Asia Minor, Egypt, Persia, and India 
yield the principal supply ; China 
also yields a large quantity. In Asia 
Minor, from whence the best opium 
used in medicine is obtained, the 
juice is collected by making incisions 
around the circumference of the 
poppy head or fruit while the plants 
are yet growing. The milky juice 
exudes slowly, soon becoming plastic 
or semi-solid, and turning brown; it 
is scraped ofi" with a knife and placed 
on a leaf of dock {liumex), which is 
carried in the left hand by the 
collector. When sufficient has been 
thus obtained to form a moderate- 
sized lump it is rolled up in the leaf 
and allowed to harden. In India 
the mode of collection is somewhat 
different ; the fruits are scarified 
longitudinally by a kind of small 
lancet, the juice is scraped ofi' in little 
scoops, and poured into bowls, in 
which part of the moisture separates. 
In the factory it is mixed or stirred 
in vats to insure uniformity of sub- 
stance, and then made into balls 
of about six inches diameter and 
covered with the dry poppy petals. 
In this condition it is stacked in racks in the opium store, 
and when required for exportation to China it is packed in 
chests divided into numerous compartments, each division 
holding one ball. Indian opium contains a much lower 
percentage of morphine than that from Asia Minor, and 
is consequently of much less value for medicinal purposes. 
It is, however, largely used for eating and smoking. 

The cultivation of the opium poppy in cool countries is 
chiefly for the sake of the capsules and seeds, the former 
for supplying the shops with " poppy heads" for making 
fomentations for allaying pain as well as for making 
syrup of poppies, and the latter for the sake of the oil they 
contain, which, when clarified, is of a sweet nature and of 
a pale straw colour, and is used for mixing with, or as a 



June 1, 1898.] 



KNOWLEDGE 



127 



substitute for, olive oil for culinary purposes, and the residue 
or marc is used for feeding cattle. Under the name of 
" maw seeds " they are given to cage birds. In this country 
the opium poppy is cultivated in many medicinal gardens, 
notably at Bodicote, near Banbury, Hitchin, and other 
places. 

Crucifer.t:. — The plants constituting this order are 
mostly of an herbaceous character, particularly abundant 
in the temperate parts of the northern hemisphere. 
Though they mostly possess pungent or biting properties, 
none are poisonous, but, on the contrary, are eminently 
wholesome and antiscorbutic. The following best known 
examples of the order will illustrate this. Horse radish 
{Cochharia aniwracia), a perennial herb naturalized in this 
country, occurring in damp, waste places, and found 
throughout the greater part of Europe. Under cultivation 
it forms a thick, somewhat fleshy root, and is much 
valued as a condiment. Mustard is another condiment of 
equal or greater value, and is the finely pulverized seeds of 
two species of Jhossica — B. alia the white, and B. niiirn 
the black mustard. They are annual plants widely distri- 
buted over Europe, B. alba occurring also in Asia Minor, 
Algeria, and China, and cultivated in the home counties 
of Essex and Cambridgeshire; while B. niijni is also found 
in Asia Minor, as well as in North Africa and North-West 
India, its cultivation in this country being chiefly carried 
on in Lincolnshire and Yorkshire. In the preparation of 
mustard, or flour of mustard of commerce, the seeds of both 
species are used mixed, and great care is taken in reducing 
them to a very fine powder which is sifted through a fine 
silk gauze. Besides the use of mustard for table purposes, 
it is an important medicinal agent on account of its power- 
ful stimulant and rubefacient properties. The cabbage 
(Brassica oh'racea) is another Ulustration of a valuable 
esculent belonging to this important order of plants. In 
its wild state it is abundant on the clifl's by the sea-coast 
in many parts of England, especially in the south-eastern 
counties. The eftect of cultivation has produced marvellous 
changes in this plant, giving us all the varieties of brocoli, 
Scotch kale, Savoy, Brussels sprouts, cauliflower, and even 
the red cabbage. The same power of culture has also 
changed the woody root of the common wild turnip 
{Brassica campestiis var. Bapa) into the fleshy, globular 
root of our gardens, while the Swede turnip has sprung 
from another variety of the same species ; and the rape, 
again, so largely grown by us as a green fodder, and on 
the Continent for the sake of its seeds, from which is ex- 
pressed rape or colza oil, has originated from still another 
variety. 

The radish (Rapliatnts satii-us) is still another of the 
esculent cruciferous roots. The plant is unknown in its 
wild state, but it has been suggested that it may have 
sprung from an allied species of the Mediterranean coast. 
In the early ages it was extensively cultivated in Egypt, 
and found its way into England about the middle uf the 
sixteenth century. Gerard mentions four varieties as 
being known in 1597. We cannot leave this interesting 
family of plants without a reference to woad, the blue 
colouring matter used by the ancient Britons to stain 
their skins, and produced by hat is tinctoria. At that early 
period its culture seems to have been general for the 
purpose mentioned above, as well as for dyeing cloths, 
but in later times the general introduction of indigo 
seriously mterfered with the use of woad ; and though it 
is still manufactured in some parts of the Continent, its 
preparation in this country is fast dying out, and at the 
present time is carried on only in the neighbourhood of 
Wisbech, and there it is still made in the most primitive 
fashion. 



Cappabide.t:. — This comparatively small order is com- 
posed of herbs and shrubby plants, very rarely trees, chiefly 
tropical, abundant in Africa, America, and India. The 
order is marked by the presence of pungent and stimulant 
properties, in this respect somewhat resembling the crucifers. 
Only one plant, however, in the order has any special 
economic value, and that perhaps of more interest than 
actual commercial value. We allude to capers, which 
are the flower buds of Cajiparis spinosa, a scrambling bush 
of the Mediterranean region. The plant is cultivated in 
some parts of France, as well as in Italy, for the sake of 
the flower buds, which are gathered and pickled in vinegar. 
The imports to this country are very small, the use of 
capers being only for culinary purposes. 

Cistinet;. — Shrubs or herbs generally known as rock 
roses, natives chiefly of Southern Europe and Northern 
Africa. They are noted for the presence of a fragrant 
balsamic resin. The best known plant is Cistus Critvus, 
a native of Crete and Cyprus, Macedonia, Rhodes, and 
other Greek islands. A resin known as ladanum is 
collected from the leaves and branches by whipping or 
bruising them with an instrument consisting of long 
leathern thongs attached to a rake-like frame. The 
thongs become coated with the resin, which is after- 
wards scraped off and moulded into small cakes. In 
Cyprus, ladanum is often collected by combing the resin 
from the fleeces of the sheep, which become loaded with it 
while they are pasturing among the plants. It possesses 
stimulant and expectorant properties, but it is seldom or 
never used in medicine at the present time ; it nearly all 
goes to Turkey, where it is used for fumigation and as a 
perfume. 

BrxiNE.F.. — A group of shrubs or trees, natives of the 
tropics, and found mostly in the East and West Indies and 
Africa. The principal economic plant of the order is the 
anatto {liixa ordlana], a tree twenty to thirty feet high, 
native of tropical America, but now cultivated in many 
tropical countries for the sake of the seeds, which are small, 
of a bright red colour when fresh, and of a waxy nature. 
It is this red coating of the seeds that forms the anatto 
of commerce, and it is removed by placing the seeds in 
water, which is stirred till the colouring substance is 
detached, when it is strained and evaporated to difi'erent 
consistencies and used for colouring cheese and butter, as 
well as for dyeing silks. Large quantities of these seeds 
are regularly imported. 

Amongst other economic plants of this order of less 
importance may be mentioned the chaulmugra (Gt/nocardia 
odorata), a large Indian tree, producing hard-skinned 
globular fruits about four inches in diameter. These con- 
tain numerous seeds embedded in the pulp, and from these 
seeds an oil is expressed known as " chaulmugra oil." It 
has an established reputation in India as a medicinal oil, 
and was introduced a few years ago to this country for 
the treatment of rheumatic affections and skin diseases. 
Its use has now, however, quite died out. 

GuTTiFEK.E. — Trees and shrubs are the plants which 
compose this order, and they are all natives of tropical 
countries. They are for the most part resinous, besides 
which many of them yield oils or fats. The best known 
resinous products are those furnished by species of Garcinia 
and collectively known as " gamboge." The most important 
of these are Garcinia Hanburyi, yielding the best quality, 
or Siam gamboge, and Garcinia Morella, giving the Ceylon 
kind. Gamboge is obtained from the first-named plant by 
making a spiral cut through the bark of the tree as it 
stands ; the yellow juice readily flows and is received into 
the hollow joints of bamboos, where it is left until it solidi- 
fies, after which the bamboos are broken away, leaving 



128 



KNOWLEDGE, 



[June 1, 1898. 



what is known in commerce as " pipe gamboge," which is 
the best and purest quality, the second quality being 
that which is collected in lumps. In Ceylon gamboge is 
collectcci either from incisions made in the bark or by 
cutting out pieces of it, from which the yellow juice oozes 
and hardens on exposure, and the lumps are then scraped 
off. Gamboge possesses powerfully purgative properties, 
and was at one time used in medicine. At the present time 
it is only used in veterinary practice. Its chief use, how- 
ever, is as an ingredient for lacquering brasswork and as 
a pigment in water-colour drawing. The well-known man- 
gosteen is the fruit of a (ianinia — (i . mamjostana. It is a 
moderate-sized tree of Malacca and the JIalay Archipelago, 
but it has been introduced into other tropical countries. 
It is the juicy pulp surrounding the seeds which is the 
delicious morsel that has caused the mangosteen to be 
classed as the best of all tropical fruits. 

Many other plants of this order might be mentioned as 
yielding important economic products, but space will not 
permit us to do so. 

TEEN^iTElEMIAcE.«. — This IS an order of trees and shrubs 
chiefly tropical. It is not marked by any character- 
istic property. In some of the South American species 
the trees are noted for their hard and heavy woods and 
the sweetness of the seeds, or nuts, as they are called, 
the Souari nut of our shops (Caryocarmiciferum) being one 
of them. The most important plant in the order — indeed, 
one of the most important in the whole vegetable kingdom — 
is the tea plant (Camellia tlna). From its early and very 
extensive cultivation in China it was for a long time 
supposed to have been a native of that country. It has, 
however, been more recently shown to have originated 
in Upper Assam, and to have been introduced to China at 
a very early period. In like manner it was supposed for a 
very long time that the black and green teas of commerce 
were the produce of distinct species. This has likewise 
been shown to be a fallacy, and it is now well known that 
black and green teas are prepared from the same plant 
by different methods of drying and curing. Thus, for 
green tea, the leaves after gathering are not allowed to 
lie so long as those intended for black tea before they 
are rolled and roasted. By this means the fermentation 
during the process of withering is avoided, and the leaves 
in consequence retain much of their natural green colour. 
Many details, which cannot be explained here, also have 
to be followed, resulting in the two commercial kinds of 
tea— black and green. In connection with the increased 
demand for tea the world over, it will be interesting to 
note that to meet that demand the range of the culti- 
vation of the plant has considerably extended in recent 
years. Thus we find it thoroughly established in Ceylon, 
while in Japan, Java, and in Natal, excellent tea is grown 
and prepared. 

The following figures will give an idea of the proportions 
of the commerce in tea so far as Great Britain is con- 
cerned: — The total imports for the year 1897 amounted to 
two hundred and sixty-nine million, thirteen thousand, four 
hundred and eighty-two pounds, of the value of ten million, 
four hundred and forty-three thousand, one hundred and 
four pounds. 

DiPTERocARPE.E. — The plants composing this order are 
for the most part large forest trees of India, noted for the 
strength and durability of their timber and for the valuable 
resinous products they yield. The best known in the first 
category is the sal or saul tree (Shorea rohusta), a tree 
forming extensive forests over a wide range in India, where 
the timber is almost, if not quite, of equal value as teak, 
and is in great demand for gun carriages, raOway sleepers, 
and building purposes generally. It, moreover, yields a 



quantity of resin known as " dammar," and used for pre- 
serving the woodwork of boats. From several species of 
Tlijileroiarpus, notably /'. aliitus, D. turhi}uitus, and Z>. 
trinenis, an oleo-resin known as " wood oil," or " Gurjun 
balsam," is obtained, chiefly from the coast of Burma and 
the Straits of Malacca. To collect the balsam, the trees 
are tapped at the end of the dry season by making several 
deep incisions with an axe into the trunks and scooping 
out a good-sized cavity. Fire is lighted in this hole, and 
when the wood has become heated or scorched the balsam 
begins to flow. After collection it is allowed to settle, 
when the clear liquid or oil separates from the more solid 
or resinous portion. It is said that as much as thirty or 
forty gallons has been obtained from a single tree in one 
season. Though it is used in India as a substitute for 
balsam of copaiba, its chief use is as a natural varnish for 
preserving woodwork from atmospheric effects or the 
attacks of white ants. The Sumatra camphor tree (Dryo- 
balanops aromatka) is of considerable interest in con- 
sequence of its peculiar habit of forming masses of 
camphor crystals in clefts of the trunks. It is much less 
volatile than ordinary commercial camphor, and fetches a 
high price amongst the Chinese, by whom nearly the whole 
of the produce of Sumatra is taken, and these people 
believe it to possess many remarkable properties. It 
does not reach Europe, except occasionally as an article 
of curiosity. 

The only other product of the I Hpterocarpene that space 
will allow us to mention is that known as " piney resin," 
or " Indian copal," the produce of Vuteria indica, a tree of 
Malabar. This resin is of a semi-fossiUzed character, and 
is used slightly in the preparation of varnish. From the 
large fleshy seeds a kind of fat or tallow is obtained, which 
is used in India for making candles, and is known as 
" piney tallow." 



WEATHER ACCOUNTS. 

By Alex. B. MacDowall, m.a. 

AN analogy might be traced between the fluctuations 
of weather and those of a banking account. And 
we might deal with the plus and minus values of 
the former (with reference to an average) as we 
might with sums deposited in a bank and sums 
withdrawn, so as to show the position of affairs at any 
given date in relation to a previous date. 

Thus, suppose a man opens a banking account, which 
he is allowed to overdraw. The first week he deposits 
ten pounds and the next ten pounds. Next he draws five ; 
then deposits ten ; then draws thirty. The final resuli 
obviously is that he is five pounds " to the bad." And 
this set of transactions, and the position each week, might 
be simply represented thus : — 

1 2 3 4 .5 

Transactions ...10 -F 10 - 5 -I- 10 - 30 = - 
State of Account ...10 -f 20 -i- 15 -h 25 - 5 

On the other hand, take as a simple case of weather 
the monthly amounts of rain in London last year. Mr. 
Symons, in his magazine, gives us the plus or minus 
values in which these are referred to an average. We 
proceed accordingly thus ; — 

Jan. Feb. Mar. April. 

+ -43 + -87 + 1-81 - -17, etc. 
4- -43 -I- 1-80 -f 3-11 -I- 2-94, etc. 

The second line, completed, we may plot as a curve 
(H, Fig. 3). 

We often hear questions like this, " Have we had more 



■June 1, 1898.] 



KNOWLEDGE, 



12J5 



or less than our share of rain ? " This curve supplies 
answers for the months of 18'.t7. The first three months 
were wet. This excess was brought down in the next 
four ; so that by the end of July we had had nearly our 



■f 3cra 
+75-0 

+ "200 

+ laa 

■tSo 



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6 12. J 
X)c<r »S97 



■J/^ 3o S II 17 23 2o M- 
3a-n. /6<29 Tib 



FiQ. 1. — Gain and Loss Curve of Daily Terapevaturo at Greenwicli last Winter. 



proper amount. But by the end of the year there 
was about two and a half inches (as we may say) still 
due. 

Let us see what kind of curve we get from the daily 
temperatures (at Greenwich) in the remarkably mild 
wmter we have lately passed through. (The relation of 
these to the average is given in the WeekUj TUturn.) The 
curve is that marked A (Fig. 1). 

In these curves a rise means a plus value, and a fall a 
minus ; we may speak of the one class as " gains," the 



downward course of the curve continue some time ? It 
would be difficult to say. 

We may take a wider survey in this matter of tempera- 
ture. Consider the years as hot or cold. Here is a curve 
(B, Fig. 2)which shows, 
in the case of Green- 
wich, the result of the 
method as applied to 
the years since 1841. 
Up to 1878 there has 
been a general rise ; 
since 1878, a general 
fall. More hot years 
than cold in the former 
case (twenty-three to 
fifteen) , more cold than 
hot in the latter (twelve 
to seven). The rise 
since 1892 may be the 
beginning of a long 
general ascent : but it 
seems not inconsistent 
with our being still on 
the " down grade." 
Can we go further back with confidence? Earlier 
figures are in some uncertainty. If we take a table of 
estimated Greenwich temperatures, by Mr. Glaisher, in the 
Philosopln>-<il Tmnsiictions for 18-30, and extending from 
1771 to 1849, and apply our method, we get the curve C. 
An interesting table by Dr. Buchan, for the North-East of 
Scotland (chiefly Gordon Castle and Culloden), from 1764 
to 1892, yields the curve D. There is a degree of similarity 
between these two curves, and they may be taken to afford 
a general idea of the truth. They dip down to low points 



2? 



-t 



>n«.r 



f^ ?*• 3o 



17^0 &> 72 'S n'SU'go '6 'mz''8 'l/f'TV '6 '32 'S '44 "io '6 '6Z. 'd '7^ '90 '6 '92. '8 




Fig. 2. — Gain and Loss Curves of Annual Temperature, Greenwich, Xorti-East Scotland, and Harvard. 



other as " losses "; and we see that in this curve, from the 
beginning of December to February 17th, the gains were 
much more than the losses. Neglecting for the present 
the individual amounts of gain or loss, we find that the 
warm days were much more numerous than the cold. 
After February 17th the balance was the other way. Here 
are some figures : from December 1st to February 17th we 
had sixty-one warm days and only eighteen cold ; there- 
after thirty-two cold days and only ten warm. Will this 



in the second and third decades of this century ; after 
which comes a long rise to the seventies. The first twenty 
years of our century evidently included some very intense 
cold. Perhaps the severest wmter of the century (thus far) 
is 1813-14, when a fair was held on the Thames, and there 
was a snowstorm lasting forty-eight hours. 

It is a curious fact that in America the weather is often 
opposite to ours. Thus, if winter is severe on the continent 
of Europe it is generally mild in America, and rice nrsd. 



130 



KNOWLEDGE, 



[June 1, 1898. 



How does America show in temperature from our present 
point of view ? E is a " gain and loss " curve, as we may 
call it, for Harvard Observatory, from 1841. It is distinctly 
opposite in character to that for Greenwich. Up to 1875, 
more cold years than hot ; since 1875, more hot years 
than cold. A similar kind of variation might be shown for 
Chicago, and, doubtless, other places. 

In all these curves, we may here note, it is the general 
trend of the curve that has to be considered, rather than 
the relation to the average line. For the starting point is 





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Fig. 3. — Gain and Loss Curves of Kainfall, Edinburgli and 
Greenwich (years), and London (moutlis of 1897). 

chosen arbitrarily, and we always commence near the 
average line. Referring to curve D, if we commenced in 
1824 we should get a curve wholly above the average line, 
instead of mostly below it, as in the diagram. 

We may now, in conclusion, briefly glance at rainfall. 
The annual rainfall at Edinburgh from 1841 to 1896 
(according to Mr. Mossman's figures), treated by our 
method, yields the curve F (Fig. 3) ; and that for Green- 
wich the curve G. 



In both of these we may observe a gradual rise from 
1858 to 1882; more wet years than dry. Thus, in the case 
of Edinburgh, of these twenty-five years, sixteen were wet 
and only nine dry. Since 1882, again, the dry years have 
preponderated ; in Edinburgh ten dry to four wet. From 
the general aspect of these curves we may, perhaps, be 
inclined to think the preponderance of dry years may 
continue some time further. 

The method here illustrated does not seem to have been 
much used in this country, but is capable, I believe, of 
throwing some light on the vagaries (as we often call 
them) of our weather. 



THE PRISMATIC CAMERA AT THE RECENT 
ECLIPSE. 

By -J. Etebshed, f.e.a.s. 

SPECTROSCOPIC research formed an important 
feature in the work of most of the astronomical 
parties who went to India to observe the total 
solar eclipse of last January, and photographic 
methods, which have so largely replaced eye obser- 
vations at recent eclipses, were, it is needless to add, em- 
ployed at every station where this analytical method was 
in vogue. 

Owing to the ideal condition of the weather ail along 
the line of central eclipse, a large number of very beautiful 
photographs are the result. The amount of interesting 
material thus secured, and which is now available for 
discussion, certainly exceeds anything obtained at any 
previous eclipse. 

Among the various lines of research undertaken by 
spectroscopists, perhaps the largest share of attention was 
given to the study of the spectrum of the layer of gases 
lying immediately above the dazzling photosphere, and 
known as the " flash spectrum." 

It may be well to explain, for the benefit of those who 
are unfamiliar with the subject, the conditions under 
which this spectrum is revealed during an eclipse. Out- 
side the visible surface of the sun, and covering the entire 
sphere pretty uniformly, there exists a stratum of gas of 
considerable depth and comparatively simple composition, 
known as the " chromosphere." Its spectrum of bright 
lines indicates the presence of the three elements calcium, 
hydrogen, and helium. This layer and the prominences 
arising from it may be seen at all times by the aid of 
powerful spectroscopes ; but the base of the chromosphere — 
that is, the region lying within one or two seconds of arc 
of the photosphere — is not accessible to ordinary spectro- 
scopic observation, on account of the perpetual unsteadiness 
of the telescopic image of the sun, and the very intense 
atmospheric illumination so near to the sun's edge. 

Now, during the progress of a total eclipse, the moon, 
advancing from the west, gradually covers up the photo- 
sphere until only a thin crescent remains on the east side, 
and this rapidly narrows down and finally vanishes alto- 
gether ; when this occurs, however, the chromosphere 
lying outside still remains uneclipsed on the east limb, 
and even the very lowest strata are uncovered near the 
point where the last streak of photosphere disappeared. 

It is just here that the most interesting and beautiful 
spectral phenomena are revealed ; bright lines flash out in 
hundreds — there seems literally to be a shower of bright 
lines all along the spectrum the moment the photospheric 
light is withdrawn — but it is only momentary ; the steadily 
advancing moon almost immediately occults the lowest 
gaseous strata and only the ordinary chromospheric spec- 
trum remains. 



June 1, 1898.] 



KNOWLEDGE. 



131 



This beautiful phenomenon can therefore only be seen or 
photographed at the momenta of disappearance or reap- 
pearance of the photosphere at the beginning and end of the 
total phase respectively. Under the average conditions of 
an eclipse, perhaps not more than two seconds are available 
just as totality comes on in which the flash spectrum may 
be photographed in its full splendour ; and if the observer 
is discerning enough to know exactly when the sun is 
going to burst out again at the end of totality, he wiU 
have another two seconds in which to expose a second 
plate ! 

It has been estimated that our opportunities for studying 
the corona do not amount in the aggregate to more than 
some hours per century, and the progress of knowledge is, 
in consequence, not rapid. How long it will take to 
unravel the mysteries of the flash spectrum it is bard to 
say, seeing that the time available for its study must be 
reckoned in minutes per century. This method of estima- 
tion is, however, certainly unjust to the photographic 
plate, which enables us to study at leisure so very transient 
a phenomenon. 

A great variety of photogi'aphic spectroscopes were used 
at the recent eclipse, but all may be classed under two 
heads, viz., slit spectrographs and prismatic cameras. 
The great advantages possessed by the latter for eclipse 
work were first pointed out by Sir Norman Lockyer, who 
employed them with great success at the eclipse of 1893, 
and again in 1896, when Mr. Shackleton first succeeded 
in photographing the flash spectrum at his station in 
Novaya Zemlia. The crowning success for the prismatic 
camera is the splendid photogi-aph of the flash which Sir 
Norman Lockyer has obtained at the recent eclipse with 
his six-inch instrument in the hands of Mr. Fowler. 

The photographs which accompany this article were 
obtained at the recent eclipse with a small instrument of 
this class, which I constructed in 1896 for the eclipse of 
that year. Without going into details as to the design of 
this particular instrument, I may say generally that the 
prismatic camera is the simplest of all spectroscopic appli- 
ances. It consists essentially of a prism placed in front 
of a camera lens. There is no slit or collimator, which in 
the ordinary spectroscope are used to give purity to the 
spectrum, and consequently it is not possible to photograph 
spectra from extended sources of light, such as the disc of 
the sun. But the prismatic camera is particularly well 
adapted for photographing the spectrum of the solar 
atmosphere during an eclipse, because, as before explained, 
when the disc is enth-ely covered by the moon there 
remains a thin crescent of light due to the layer of gases 
outside, and which acts the part of a curved slit. If the 
moon and sun were precisely equal in apparent size this 
would extend all round in a ring, and would produce con- 
siderable confusion in the spectral images ; but under 
ordinary circumstances the moon is slightly the larger in 
angular diameter, so that early in the total phase the 
chromospheric gases appear as a half circle or crescent on 
one side only, while later on this is in turn eclipsed and 
the opposite portion is uncovered. 

In the succession of photographs given in the plate it 
will be noticed that the spectral images of these crescents 
exhibit this change, which occurs about the time of mid- 
totality (between Nos. i and 7). It will of course be 
understood that, owing to the essential nature of gaseous 
radiation, and to the wonderfully complete mixture of gases 
existing at the base of the chromosphere, an enormous 
number of distinct images or spectrum '• lines " are shown 
in the photographs taken near second and third contact. 
The pair of very strong images to the left hand of the 
central portion of each spectrum are those due to the well- 



known radiations of calcium vapour, namely, H and K ; 
they give complete images of the chromosphere and pro- 
minences — or, rather, as much as was uncovered by the 
moon at the time each photograph was taken. 

Before proceeding to describe in detail the results 
obtained, I will give a brief description of the arrange- 
ments I made for this work at the camp of the British 
Astronomical Association stationed at Talni. 

My plan of work was first to obtain a series of ten 
photographs with the prismatic camera during totality, 
and including, if possible, the flash spectrum at both 
second and third contacts ; secondly, to photograph the 
flash spectrum on a larger scale with a large slitless 
spectrograph attached to a six-inch telescope; and, thirdly, 
to expose a single plate to the spectrum of the corona 
during the whole time of totality by means of a slit spectro- 
graph containing quartz prisms. 

Besides these three photographic instruments I had 
available a four- inch polar heliostat, kindly placed at my 
disposal by Mr. W. H. Maw ; and a three and a quarter 
inch equatorial telescope provided with a powerful solar 
spectroscope, with which I intended to actually observe 
the flash of bright lines at second contact, and thus 
determine the exact moment when to expose the photo- 
graphic instruments. 

The heliostat, which I arranged with two four-inch 
mirrors instead of one, was used to supply light to the 
prismatic camera and to the slit spectrograph, both these 
being mounted on fixed supports firmly bedded in cement. 
The six-inch telescope with its spectrograph was mounted 
equatorially, but without any driving gear, and was 
pointed directly at the eclipsed sun. 

As there would be no one available on the day of the 
eclipse to assist me, the three photographic instruments 
bad to be arranged with their exposing shutters near 
together, so that I could work them all while seated near 
the telespectroscope. 

The diagram will show better than any description 
the disposition of the various instruments within the 
observing hut. 




H- SOUTH. 

Px.Ay OF Obsebving Hut. 

E. Equatorial Telespectroscope ; H. Heliostat ; PC. Prismatic 
Camera ; SG. Spectrograph with Six-inch Object Glass ; ss. Slit 
Spectrograph with two Quartz Prisms. 

Thanks to the facilities afforded by the Indian (.iovern- 
ment in providing workmen and materials, and to the 



132 



KNOWLEDGE. 



[June 1, 1898. 



very attentive way m which all our needs were provided 
for by the Deputy Commissioner of the district, Lieutenant 
Morris, I was able to get everything erected and in 
working order during the fortnight preceding the ecHpse. 
In adjusting the instruments and putting together the six- 
inch telescope and spectrograph I had also the advantage 
of receiving moat elBcient help from Captain Molesworth, 
R.E., without whose skilled assistance it would have been 
impossible to get all ready in time. 

On the day of the eclipse the actual procedure was as 
follows : — About ten minutes before totality the heliostat 
was started going and the mirrors adjusted. Then the 
exposing cap of the prismatic camera was put on and the 
first plate drawn up into position by means of a rack- 
and-pinion arrangement which I had made for this instru- 
ment to obviate the necessity for " changing plates " 
after each exposure. Next, the exposing shutter of the 
slit spectrograph was closed and the dark slide drawn 
out ready. 

At eighty-eight seconds before second contact the six- 
inch telescope was adjusted and clamped in such a position 
that the diurnal motion would carry the image of the 
eastern edge of the sun exactly into the middle of the 
field of the spectrograph at the moment of second contact. 
This was effected by moving the telescope until the image 
of what remained of the sun touched a certain mark 
previously made on a screen placed in the focal plane, 
and keeping it there by following in R.A. until the 
chronometer I was using indicated eighty-eight seconds 
before totality. 

During the last half-minute before the eclipse was total 
I began exposures with the prismatic camera, taking two 
instantaneous photographs of the cusp spectrum, and then 
drawing another plate into position ready for the " flash." 

Now, all being ready, only a few seconds remained 
before the bright lines of the flash spectrum might be 
expected to appear. The gloom of the approaching 
shadow was already increasing at an alarming rate. I 
turned to the visual spectroscope, took oS' the slit head, 
and watched the spectrum of the last remaining thread of 
sunlight without any slit. The well-known j,'roups of dark 
lines composing the ordinary solar spectrum were seen at 
first just as though the slit had not been removed, but 
they were curved arcs instead of straight lines, each taking 
the form of the little crescent of photosphere remaining 
uncovered. 

The band of continuous spectrum in which these dark 
lines appeared was seen to be rapidly narrowing, but, 
instead of thinning down to a single thread, the roughness 
of the moon's edge caused it to suddenly break up into a 
number of strips with dark spaces between, and at this 
instant the bright lines flashed out in hundreds between 
and across the streaks of continuous spectrum. I was 
astonished at the suddenness of the reversal from dark 
lines to bright, and at the brilliancy and extreme sharpness 
of the lines ; many of them extended for thirty degrees or 
more round the limb of the moon, but interrupted here 
and there by the projecting lunar mountains. 

Without waiting for further developments I immediately 
exposed the prismatic camera and the large spectrograph, 
in hopes that the photographic plate would be equal to the 
occasion and duly record this wonderful display. 

In the resulting photograph (No. 3) certainly not all of 
the finer lines are depicted which I could see reversed in 
the part of the spectrum I was observing. But in the 
ultra-violet, where the definition is best, an extraordinary 
wealth of fine lines are shown ; and this end of the photo- 
graph gives a good idea of what I actually saw near the 
group /' in the green. 



Immediately after second contact I made an instan- 
taneous exposure with the prismatic camera — the fourth of 
the series — and then started a series of long exposures, at 
the same time opening the shutter of the slit spectrograph. 

During the first long exposure I left the seat near the 
heliostat and closed the slide of the large spectrograph, 
reversed it, and opened again ready for the second flash. 
Then I had to turn the right ascension handle four revolu- 
tions to bring the west limb into the field of the spectro- 
graph at third contact. The forty seconds occupied in 
this way with my back to the eclipse was an ordeal which 
I trust I may never again have to undergo ! After returning 
to the seat I closed the long exposure and started another ; 
then I had a look, for the first time, at the corona. With 
a pair of binoculars I examined the beautiful streamer on 
the south-west side which was so successfully photographed 
by Mrs. Maunder (see the May Number of Knoi\xedge). 
But almost before I could gain any very distinct impressions 
I was interrupted by the time caller, only twenty more 
seconds remaining before the sun would reappear ! It was 
necessary to close the long exposure, expose another short 
one, and then look out for the flash again. 

Fortunately I made the exposure for the second flash 
spectrum just as the first points of sunlight burst into 
view on the west limb, forming what is known as 
" Bailey's Beads." (See No. 8.) 

Two more snap shots with the prismatic camera taken 
in rapid succession completed the programme. 

The whole performance seemed to have gone ofif without 
any serious hitch, but too late I discovered the slit spectro- 
graph still open, with the crescent sun right across the 
slit ! I had forgotten to close the shutter in the hurry of 
the last moments of totality. 

The number of photographs secured altogether was 
thirteen ; one with the slit spectrograph, two with the 
large spectrograph, and ten with the prismatic camera. 

The single photograph obtained with the first named 
failed from the above-mentioned cause, the direct sunlight 
and halation nearly obliterating the faint coronal spectrum. 

The large spectrograph yielded two negatives of the 
flash spectrum which show a considerable number of lines 
in a limited region of the spectrum, but on the whole they 
do not quite come up to expectation. The best results 
were those obtained with the prismatic camera. This 
instrument gave images of the spectrum extending from 
A 600 in the orange to A 338 in the ultra-violet. The 
scale of the original negatives is -33 inch to the moon's 
diameter and one inch from F to H, the total length of 
spectrum photographed being 2-8 inches. 

All the ten exposures yielded good negatives. Nos. 1, 2, 
9, and 10 of the series give the spectrum of the cusps just 
before and just after the total phase. They show the 
P^aunhofer dark-line spectrum bordered with bright lines, 
and in \o. 10 nil the dark lines in the ultra-violet end in 
a short bright line. 

The flash spectrum lines are shown in Nos. 3, 7, and 8. 
In No. 3 they are beautifully defined in the ultra-violet 
from H upwards, and this photograph is certainly the 
finest of the set. It will be necessary to study it in great 
detail by means of enlargements and with the help of the 
Fraunhofer spectrum (obtained under precisely the same 
angle of incidence) given in Nos. 1 and "2. 

Of the remaining plates, No. 4 reveals a very curious 
feature in the prominence spectrum. In the ultra-violet 
are seen a succession of little dots due to the hydrogen 
radiations, and at the point where these terminate (at 
K 3660) the spectrum abruptly changes its character and 
becomes a continuous one, a delicate line running from 
the last dot to the end of the plate. 



l\'noirh'd{ie. 




ECLIPSE SPECTRA. 

Photographed with Prismatic Camera. 2\ inches Aperture, 36 inches Focus. 



June 1, 1898.1 



KNOWLEDGE 



133 



The long exposures made near mid-totality show the 
distribution of " coronium " in the corona. The well- 
known radiation of this gas, 1 171 K, is, in these, shown 
to correspond more or less with the general structure of 
the corona ; but it is very much brighter on the east side 
than on the west, where it is hard to trace it at all. 

Six out of the ten photographs taken are reproduced in 
the plate, enlarged about two and one-third times. The 
series number is given beside each spectrum, iluch ot 
the delicate detail shown on the original negatives is 
inevitably lost in the reproduction, although the main 
features are well brought out. In referring again to the 
flash spectrum, as seen in Nos. 3 and 7, I would call 
attention to the beautiful sequence of the hydrogen lines 
(the positions of these referring to No. 3 are given at the 
top of the plate). I do not know that these lines have ever 
before been photographed in such completeness in the 
chromosphere spectrum. In the original negative twenty- 
six or twenty-seven lines can be counted, starting with the 
line a at the red end. In the ultra-violet they become so 
closely crowded together that it is not easy to say exactly 
how many there are and where the series ends. According 
to the well-kuowu empirical formula of Balmer, which 
expresses with such extraordinary accuracy a series of 
numbers given by nature, the limit should be at >. 3(ji7, a 
position in the spectrum which is indicated by an arrow 
at the top of the plate. In the photograph, however, 
there is a beautifully regular gradation in the intensity 
of the lines, which become fainter and fainter as this limit 
is approached, so that line No. 27 (A SCUM) is so exceed- 
ingly faint as to be barely distinguishable, and it apparently 
forms the termination of the series. 

Another point which is well shown in No. 3 is that, if 
we except the ordinary chromosphere lines (those of 
calcium, hydrogen, and helium), all the fainter lines due to 
the flash spectrum proper are of the same length and form, 
a well-defined band of even width running from end to end 
of the spectrum. This shows that the low-lying gases at 
the base of the chromosphere form a well-defined layer 
pretty definitely bounded, and not fading by insensible 
gradations into the higher portions of the chromosphere. 

An estimate based on the width of this band of bright 
lines gives for the depth of the layer about one and a 
half seconds of arc — or say seven hundred miles — the total 
depth of the chromosphere itself being some eight seconds 
of arc, or three thousand six hundred miles. 

The limits of this article preclude my entering upon 
the discussion as to the relation between the flash spectrum 
lines and the Fraunhofer spectrum, beyond saying that, 
from a careful consideration of the facts so far brought to 
light, I am inclined to believe that the flash 
spectrum does in fact represent the upper 
portion of the layer which by its absorption 
gives us the ordinary dark- line spectrum, as 
was held by Prof. Young, who first discovered 
the so-called "reversing layer" at the eclipse 
of 1870. 

I think that too much stress has been 
laid upon the fact that, while the flash 
spectrum lines correspond in position with 
the Fraunhofer lines, yet in relative intensity 
there are marked differences. This, it seems 
to me, is only what we should expect to be the case when we 
consider that in the one case we are looking tangentially 
through the higher parts of the layer (which, it is to be 
remembered, is some seven hundred miles in depth, with 
a probable enormous increase of density at the base), while 
in the other the line of sight passes entirely through the 
layer from top to bottom. 



OCCULTATION OF 26 ARIETIS OBSERVED 
PHOTOGRAPHICALLY. 

THE disappearance of a bright star when occulted 
by the moon is always a striking phenomenon. 
There is no celestial event whose time is susceptible 
of more precise determination. For many years 
various plans have been suggested, both here and 
elsewhere, by which this time could be determined with 
greater accuracy than by ordinary visual observation. In 
fact, the apparatus for photographing the eclipses of 
Jupiter's satellites, used here for several years, was devised 
in part for this purpose. 

On February 2.5th, 1898, Mr. Edward S. King for the first 
time succeeded in satisfactorily photographing the occul- 
tation of a star. The apparatus used was an improved 
form of that constructed for photographing the eclipses of 
Jupiter's satellites, and described in the Astrnpln/^ical 
.Journal, Vol. I., p. 146. The plate was moved automatically 
every second by means of an electro-magnet. A motion 
of about 303 cm. was given to the plate whenever the 
circuit was closed, and of an equal amount when it was 
opened. Connecting the apparatus with the standard 
clock, Frodsham 132'7, two images alternately faint and 
bright were obtained every second. As the faint images 
are three magnitudes fainter than the bright images, the 
ratio of the durations was about one to sixteen, so that 
the absolute durations were O-OGs. and 0'.»ls. It is here 
assumed that, as the times of exposure were very short, 
the chemical action was proportional to the time. This 
assumption is verified by actual measurement. 

Considering only the images taken during the minute 
following 6h. 35m. Os., the bright images of 26 Arietis, as 
shown, are equally intense, including that having an 
exposure lasting from oQ-OGs. to SlOOs. Since this image 
appears to be as bright as the others, the light of the star 
could not have begun to diminish much before the time 
51003. If the star had disappeared suddenlyat 50-!»3. the 
last image would be at least 012 of a magnitude fainter 
than the others, an amount readily measurable. The next 
image is apparently invisible. Had the disappearance 
taken place at 51-06s. the image would appear, and would 
be as bright as the other faint images. A slight darkening 
of the film is perceptible near the position the next image 
would have had, with an intensity nearly equal to that of 
the fainter images. If this were due to the star it would 
denote that the latter suddenly disappeared at about 5ri2s. 
The absence of the preceding image would indicate a more 
gradual disappearance. In any case, the time is fixed at 




Occultatioa of 20 Arietis. (Kiilargod 10 times.) 

51-ls., to within one-tenth of a second. As the clock was 
2m. 19-ls. fast, not including armature time, the corre- 
sponding Greenwich mean time is 12h. 51m. 26"5s. By 
using shorter exposures the uncertainty in the time of dis- 
appearance can doubtless be greatly reduced, especially in 
the case of the brighter stars. Since satisfactory images 
of 26 Arietis, magnitude 01, were obtained in OGs., it is 



134 



KNOWLEDGE, 



[Juke 1, 1898. 



probable that occuUatione of stars as faint as the ninth 
magnitude can be observed photographically. 

Measures were next made of the intensity of the last five 
images of 26 Arietis, to see if there was any diminution in 
light due to the absorption of a lunar atmosphere. The 
distances of these images from the moon's limb were 1-8 ", 
I'i", 1-0", O'C", and 0-2", respectively. The corresponding 
changes in light expressed in magnitudes as compared with 
ten more distant images were +003, +0-03, —0-02, 
+ 008, and — 0-02. A positive sign denotes that an image 
was fainter than those at a greater distance from the 
moon. From this it appears that no diminution in light 
was perceptible. No correction need be applied to any of 
the above calculations for the diameter of the star's disc, 
since, assuming its intrinsic brightness equal to that of the 
sun, its time of disappearance would be only 0-002s. [Proc. 
Anwr. Acad., XVI., p. 1. 

In this connection it is interesting to note that the 
determination photographically of the position of the moon 
by means of a star about to be occulted, was one of the 
subjects investigated by Prof. G. P. Bond forty years 
ago. He obtained a number of photographs of the moon 
and a Virginis shortly before the occultation of the latter 
on June 2nd, 1857. 

A VARIABLE BRIGHT HYDROGEN LINE. 
The presence of the bright hydrogen line H^ in the 
spectrum of the star A. G. C. 9181 was found from the 
Draper Memorial photographs in 1895, and was announced 
in the Astrojihi/xical Journal, Vol. I., p. 411. From a 
comparison of photographs of this object taken on different 
dates Miss A. J. Cannon finds that this line is variable. 
On October 5th, 18!i2, it was invisible. On November 28th, 
1894, it was about half as bright as the corresponding line 
in A. (i. C. 9198, uj Canis Majoris. On April 27th and 
30th, 1895, the line in A. G. C. 9181 was distinctly the 
brighter of the two, while in January, 1897, it was again 
invisible. From a large number of photographs of this 
object taken recently it appears that this line, which was 
bright in October, 1897, is now, December 27th, invisible. 

A NEW SPECTROSCOPIC BINARY. 

From an examination of the Draper Memorial photo- 
graphs Mrs. Fleming finds that the star A. G. C. 20203, 
fi Lupi, is a spectroscopic binary. The period has not yet 
been determined, but photographs are being taken for this 
purpose. 

Measures of the spectroscopic binaries, jw.' Scorpii and 
A. G. C. 10534, show that the relative velocities of the 
components are approximately 460 km. and 610 km. 
respectively. The velocities are therefore much greater 
than in the case of ? Urs.T Majoris and /3 Aurigrc. The 
separation of some of the lines amounts to as much as 
nine tenth-metres. 

PHOTOGRAPHIC SPECTRUM OF THE AURORA. 
Various attempts have been made at this observatory to 
photograph the spectrum of the aurora. In 1880 on several 
occasions long exposures were given to plates during bright 
auroras, but no result was obtained. On April 1, 1897, 
Mr. Edward S. King succeeded in obtaining a photograph 
in which four bright lines were visible, but imcertainty 
existed regarding their wave lengths. The exposure was 
one hundred and forty-seven minutes. During the bright 
aurora of March 15th, 1898, he obtained a photograph 
showing two bright lines. The exposure was one hundred 
and forty-one minutes. The brightest of these lines extends 
in wave length from about 3892 to 3925, and the wave length 
of the second is 4285. Assuming the two brighter lines 



photographed in 1897 to be identical with these, the four 
lines on that plate have the wave lengths 3862, 8922, 
4288, and 4094. The first of these lines is very faint. 

The errors of measurement of these lines do not exceed 
one or two units, but much greater uncertainty exists in 
the reduction owing to difliculties in comparing them with 
the lines of the solar spectrum, which was photographed 
upon the same plate. Probably the two auroras gave 
difi'erent spectra. That in 1897 was taken with a wide 
slit, but the images of the lines were well defined on the 
edges and of equal width, so that the line 3922 was 
probably really narrow and coincident with the edge of 
^greater wave length of the line 3892 to 3925. The 
spectroscope used was not especially designed for photo- 
graphing faint surfaces, and it is hoped that better results 
may be obtained with a new instrument now in course of 
construction. As is the case with all results announced 
in these circulars, it is expected that full details will be 
published later in the annals of the observatory. 
Harvard College Observatory. Edwabd C. Pickebdco. 



Notf»0 of ISoolts. 



The Smithsonian Institution, 1^40-1890 : the Histor;/ af its 
First IJalf-Century, Edited by George Brown Good. (City 
of Washington.) When James Smithson, in 1826, drew 
up his will [containing this most significant provision, " I 
bequeath the whole of my property to found at Washington, 
under the name of the Smithsonian Institution, an estab- 
lishment for the increase and diffusion of knowledge among 
men," he laid the foundation of an organization which, 
for half a century, has been one of the most important 
agencies in furthering the intellectual development of man- 
kind. The institution is a rallying point for workers in 
every department of scientific and educational activity, and 
the chief agency for the free distribution of books, apparatus 
of research, and of scientific intelligence throughout the 
world. Its pubUcations, which include some hundreds of 
volumes, are sent to all the most important libraries in the 
world, and many of them, it is safe to say, are found on 
the work-table of every scientific investigator. In view of 
the present enthusiasm for the idea of the federation of the 
Anglo-Saxon races, it may not be inopportune to point out 
that James Smithson was an Englishman who graduated 
at Oxford in 1786. "The best blood of England flows in 
my veins," he once wrote ; " on my father's side I am a 
Northumberland, on my mother's I am related to kings." 
This sumptuous volume contains a complete history of the 
Institution, and appreciative notices (each by a distinguished 
man of science) of the various branches of work carried out 
under its auspices during its existence. Though the plan 
of the volume is due to the late Dr. Goode, the enormous 
labour involved in seeing the work through the press has 
fallen upon Prof. S. P. Langley, the present secretary of 
the Institution, whose own contributions to science have 
placed him in the foremost rank among investigators of 
natural phenomena. The volume is in every way a worthy 
jubilee memorial ; the printing, the plates- — in fact, the 
whole /on/(a; — leave nothing to be desired ; and whoever is 
fortunate enough to obtain a copy may well be gratified at 
his possession. 

Memorials of William Cramh Bond and of his timi George 
Phillips Bond. By Edward S. Holden. (1897. Ban 
Francisco, C. A. Murdock & Co. ; New York City, Lenicke 
Buechner.) It is not given to every man to be a 
Boswell, but the pity of it is that would-be Boswells do 
not recognize the fact, and assume the rule. The first 
part of this book is extremely dull. It consists largely of 



June 1, 1898.] 



KNOWLEDGE. 



135 



autobiographical or biographical sketches of a Bond by 
himself or by another Bond, and the rest is a repetition of 
the same, paraphrased by Prof. Holden. The second part 
is not so dull, consisting as it does of Prof. George Bond's 
diary during his visits to Europe. Its interest chiefly 
lies in the comments of a personal nature on contemporary 
philosophers. We confess to being mterested in hearing 
that he " found M. Plantamour a young man of thirty, 
and very good looking for a savant": that he noticed 
" that the most distinguished scientific men are bad. 
hesitating speakers — except, perhaps, Sir John Herschel." 
The last part of the book consists of letters from or 
to the Bonds from other scientists, which are simply the 
short epistles that one astronomer must write to another 
in the ordinary course of business. We fail to see why 
they were inserted, except that they occupy some sixty 
pages. 

A Treatise on Magnetism and Electricity. By Prof. 
Andrew Gray, LL.D.,F.R.s. (London: Macmillan andCo.) 
143. net. Students of physics have been long awaiting 
the publication of Prof. Gray's treatise on magnetism and 
electricity, the first volume of which is now before us. 
The plan adopted is to " regard electric and magnetic 
forces as existing in a space-pervading medium in which 
the electric and magnetic energies are stored, and by which 
they are handed on from one place to another with a finite 
velocity of propagation." We need hardly say that this 
modem plan of regarding the subject has, in the hands of 
Prof. Gray, resulted in a book which no serious student of 
physics can afford to neglect. Though an elementary 
acquaintance with electric phenomena and apparatus is 
assumed, the reader possesed of a fair knowledge of the 
calculus will have no difficulty in intelligently following 
the subject as it is here presented. As stated in the words 
of Bacon, quoted upon the title page; "All true and fruit- 
ful natural philosophy hath a double scale or ladder, an 
as3endant and descendant, ascending fi-om experiments to 
the invention of causes and descending from causes to the 
invention of new experiments." Prof. Gray is concerned 
with both these processes ; and by showing how, first, 
electrical phenomena can be satisfactorily explained by 
action in a medium, he is able to also indicate the con- 
sequences to which they lead. This treatment is the 
natural outcome of the pioneer work of Maxwell, who, 
following the ascendant ladder, elaborated a mathematical 
theory of electricity which was not only retrospective but 
prophetic. The volume, of nearly five hundred pages, 
includes an account of the ordinary facts of magnetism 
viewed from a theoretical standpoint, a discussion of 
electrostatics and electric currents, of electro-magnetism, 
and of the electro-magnetic theory of light. It wUl un- 
doubtedly occupy a prominent place as a book of reference 
in every well-equipped library, and will be read wherever 
the modern aspects of magnetism and electricity are 
studied. 

Mcwori/ and itx C'.dti ration. By F. W. Edridge-Green, 
M.D., F.R.c.s. (Kegan Paul, Trench, Trubner, i Co.) 
The author of this addition to the " International Scientific 
Series " claims that the facts he has discovered enable him 
to learn a subject in about a fifth of the time that it pre- 
viously took him. With such a tempting allurement, one 
sets about the task of reading the manual with no little 
avidity. Unfortunately, however, it is difficult to main- 
tain this preliminary enthusiasm. Though a few of the 
instances given to exemplify the statements made are in- 
teresting reading, we very much doubt whether the volume 
will find many appreciative readers. The idea of using a 
physiological basis for the analysis of memory is good, but 



it needs more careful treatment than it receives in the 
present book. Physiologists and psychologists wiU be 
content to differ from Dr. Edridge-Green's view, that 
"memory is a definite faculty, and has its seat in the 
basal ganglia of the brain, separate from, but associated 
with, all the other faculties of the mind " (page 8). 
As for the author's elaborate scheme of thirty-seven 
faculties, it would perhaps be kindest to limit ourselves to 
the statement that scientific men consider them fantastical 
and that the general reader will find them misleading. 
Whoever purchases the book with the idea of improving a 
bad memory will be disappointed ; and few people will be 
deeply interested in the views which the author has taken 
the pains to expound. 

Ainhroise Par' and his Times. By Stephen Paget. 
(G. P. Putnam.) This is a very attractive volume, beauti- 
fully printed and well illustrated. As most of our readers 
will know, Pare was contemporary with a number of dis- 
tinguished men whose names are famUiar to everyone. We 
need only mention Shakespeare and Rabelais, Calvin and 
Knox, to enable Part 's place in history to be located. He 
was born three years before the battle of Flodden Field, 
and died (after an eventful life of eighty years) a year and 
four months after the destruction of the Armada. The 
volume, upon which we cordially congratulate Mr. Paget, 
is well worth reading. It is brimful of interesting matter, 
and though it is but natural that the ".Journeys in Diverse 
Places " from Part's own pen should attract most attention, 
yet Mr. Paget's work is well able to sustain the reader's 
interest throughout. To medical students and practising 
surgeons this biographical sketch should be particularly 
readable. How many of them would be content to do as 
Pare did at Turin ? This is what he says in the " Journey 
to Turin," 1537 : " I found a surgeon famed above all others 
for his treatment of gunshot wounds, into whose favour I 
found means to insinuate myself, to have the recipe of his 
' balm,' as he called it, wherewith he dressed gunshot 
wounds. And he made me pay my court to him for two 
years before I could possibly draw the recipe from him. 
In the end, thanks to my gifts and presents, he gave it to 
me." (Page 3.5.) Knowledge is more easily gained nowadays 
and is less highly prized. 



SHORT NOTICES. 

The Centuries. Second Edition. (Xewman & Co.) ob. 6d. post free. 
Intended to supply a skeleton conspectus of general history, and to 
serve at the same time as a note-book for the reception of additional 
memoranda, this book is designed as a study-table companion for 
readers in biography or history. It forms a chronological synopsis of 
history on the " space-for-time " method, a page being allowed for 
every century, which is divided into ten-year periods, and each event 
is inserted as nearly as practicable in its proper position. The year 
'• one," it is edifying to note, in this work is placed ten thousand 
years before the Christian era ! 

Modern Architecture. By H. Heathcote Statham. (Chapman 
& Hall.) Illustrated. Mr. Statham has treated a very intncate 
subject in a lucid style. At the preseut day bridges, theatres 
and many buildings of a commercial kind are too frequently con- 
structed rapidly and without any serious effort at artistic effect. 
Believing that the sight of artistic buildings will produce ennoblin" 
results on the rising generation, the author in Iiis book — which is 
compreheusive, and embraces street, public, and domestic architecture 
— exerts himself to arouse greater enthusiasm for decorative effect in 
those who have never been able to raise themselves above the purely 
utilitarian. 

Elementary Sotan)/. By Percy Grroom, M.A., F.L.s. (George Bell & 
Sons.) Illustrated. Ss. 6d. " Though by no means a ' cram book ' 
for elementary examinations, a thorough knowledge of the contents 
of this book will enable a candidate to pass with distinction." This 
is what the author says in his preface. Mr. Groom insists on the 
free use of the simple microscope in commencing the study of botany, 
and in these lessons the compound microscope is deemed unnecessary. 



136 



KNOWLEDGE 



[June 1, 1898. 



A somewhat norel departure in the work consists in the study of 
vegetable physiology prior to a knowledge of the histology of plants ; 
a plan which, we think, is open to criticism, inasmuch as it is fairly 
comparable to entering upou the study of a steam engine before hariag 
mastered the principles inToIved in the simple mechanical powers. 

The Suilding of the Intellect. By Douglas M. Ganc. (Elliot 
Stock.) 58. The author of this book endeavours to present to the 
reader some of the leading views pertaining to man's education in 
all its aspects. He says : " Education being now regarded as a 
question of such Tital importance, and opinions differing so widely 
as to its method, character, and scope, a summary of the views of 
tliose best qualified as guides and teachers cannot fail to arrive at 
something like unanimity of ojjinion." The volume, which is happily 
hung together, consists mainly of extracts from recognized authorities, 
the author modestly preferring tliis method rather than the bolder 
plan of clothing their opinions in his own words. 

We hnve received from Messrs. Darlington & Co., of Llangollen, a 
parcel of their excellent handbooks for tourists, including their new 
" Guide to London," by Mrs. E. T. Cook. This latter is probably the 
most complete handbook to London ever issued. It is fully illustrated 
with maps, plans, and views of the great city ; contains a most in- 
forming index ; and is both well written and admirably planned. 
Finally, Mr. E. T. Cook has himself contributed the chapters on the 
British Museum, the National Gallery, and the National Portrait 
Gallery. 

BOOKS RECEIVED. 

The Flora of Perthshire. By Francis Buchanan W. White. 
(Blackwood.) 7s. 6d. net. 

The Cid Ballads. By the late .Tames Young Gibson. Edited by 
Margaret Dunlop Gibson. (Kegan Paul.) Portrait. 12s. 

The First Philosophers of Greece. 'By Arthur Fairbanks. (Kegan 
Paul.) 

The Epic of Sotnids. An Interpretation of Wagner's "Niebeluugen 
Ring." New Edition. (Novello.) Illustrated. 3s. 6d. 

Flemeiitari/ General Science. By A. T. Simmons and L. M. Jones. 
(Macmillan.) Illustrated. 3s. 6d. 

' First Stage Magnetism and Elect riciti/. ByR. H.Judc. (Clive.) 
Illustrated. 2s. 

Heturn — Technical Education — Application of Fnnds hif Local 
Authorities. (Spottiswoode.) Is. 6d. 

Text-Book of Physical Chemistry. By Clarence L. Speyers. 
(Spou.) 

Electro-Physiology. By W. Biedermaun. Translated by Francis 
A. Welby. Vol. II. (Macmillan.) Illustrated. 17s. net. 

The Story of Photography. By Alfred T. Story. (Newnes.) 
Illustrated. Is. 

Responsible or Irresponsible ! Criminal or Mentally Diseased ! 
By Henry Smith, m.d. (Watts & Co.) Is. 

Scientific Method in Bioloi/t/. By Dr. Ehzabetli Blackwell. 
(Elliot Stock.) 

Industrial Electricity. Edited by A. G. Elliott. (Whittaker.) 
Illustrated. 2s. 6d. 

The Process Year-Book for 1S98. (Penrose.) Illustrated. 

London in the Time of the Diamond Jubilee. By EmUy Constance 
Cook. (Darlington & Co., Llangollen.) Illustrated. 



Urttevs. 



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

" THE MASSES AND DISTANCES OF THE BINARY STARS." 
To the Editors of Knowledge. 

Sirs, — Referring to Mr. Gore's paper on the " Masses 
and Distances of the Binary Stars." In his paper of 
December, 1894, he used — 25-5 as the stellar magnitude 
of the sun. In his present paper he assumes —27, but 
assigns no reason for the change. Will he explain 'r 

The word " brightness " seems to be used by Mr. Gore 
in a sense in which I think it implies something he does 
not intend. I may be wrong, but I think he means 
"quantity of light." We cannot tell how "bright" 
a star is when we only know its mass and distance. 
We could if we knew its surface and distance. Assum- 
ing that Mr. Gore is right in his data for y Leonis, for 



instance, and that its mass equals that of the sun, while it 
emits two hundred and sixty-three times as much light 
as the sun : this may be accounted for either on the 
supposition that it is two hundred and sixty-three times 
as bright, or a little over sixteen times the diameter of 
the sun, or evidently any compensatory variations in the 
two data. Of course Mr. Gore knows all this, but the 
doubleuseof the word "brightness" gives trouble in reading 
his papers, and leads him into such a sentence as, " Hence 
we see that Sirius is nearly ten times brighter than it 
would be had it . . . the same brightness of surface 
as the sun has." It cannot be hri<jhter if of the same 
brhjhtness. When I light a second candle I get twice 
the surface and twice the light of the one, but neither 
candle is brii/hter than the one first lighted. 

Edwin Holmes. 



To the Editors of Knowledge. 

Sirs, — Mr. C. B. Holmes's detection of Mercury on 
April 12th, seven minutes after sunset, would certainly 
establish " a record for a London view " if the object he 
saw can be unquestionably identified as Mercury. The 
planet Venus was, however, in the very same region of 
sky, and not more than about six and a half degrees 
distant, in a south-westerly direction, from Mercnry. If 
Mr. Holmes really observed the latter, then he must 
naturally have also seen the far more brilliant object 
\'enus. 

Your correspondent's observation is such a remarkable 
one that I am induced to suggest that Venus may possibly 
have been mistaken for Mercury. On consulting my 
note-books, I find that though I have obtained at least 
ninety-four naked-eye observations of Mercury, I have 
never been able, under the most favourable conditions, to 
distinguish the planet within half an hour of sunset. 

Bristol, 1898, AprU 29th. W. F. Denning. 

"DESERTS AND THEIR INHABITANTS." 
To the Editors of Knowledge. 

Sirs, — Mr. Lydekker, in your last issue (p. 101), ridicules 
" the idea that flints and other stones grow." As one with 
"more or less intimate acquaintanceship with science" 
I think his illustration unfortunate and misleading, for if 
segregation means growth — which I assume it does — then, 
startling as it may appear, stones do " grow." 

G. Abbott, m.e.c.s. 

[Your correspondent fails to reahze the difference be- 
tween rocl.s and stones. Rocks, during their formation, 
such as the sand and shingle of our beaches, may, in a 
sense, be said to gro^v ; but the stones composing such 
shingle grow only in one way — that is, less. Similarly, 
congretions and segregations, such as flints, grow while in 
course of formation in their native rock, but, when denuded 
and reduced to the condition of stones, only alter in size 
by diminution. I must decline further discussion on the 
matter. — R. L.] 



A LITTLE pamphlet giving " Local Particulars of the Total 
Eclipse of the Sun on May 27th, 1900, ' has just been 
issued from the XKUtical Almanm- office. In America, the 
path of the moon's shadow reaches from New Orleans in 
Louisiana to Norfolk in Virginia ; and in the Eastern 
Hemisphere, from Oporto in Spain to Algiers in Northern 
Africa. 



June 1, 1898.] 



KNOWLEDGE. 



137 



Raoul Pictet, of Geneva, and Louis Paul Cailletet, of 
Paris, received the Davy medal of the IJoyal Society, in 
1878, for their researches on the liquefaction of gases — 
including hydrogen, which, however, was scarcely more 
than a mere fog in the glass tube. I'rof. Dewar has 
during the past month performed the unprecedented feat 
of liquefying hydrogen to the amount of half a wineglass- 
ful in five minutes. The boiling point of hydrogen is 
— 240° C, and the density of the liquid, there is reason to 
believe, is about 0-6, water being talien as the unit. 

Prof. Boyd Dawkins, in a letter to the " Times " dated 
7th May, protests against the removal of the Jermyn 
Street Museum andLibiary to South Kensington, recom- 
mended in an interim report of the Select Committee. He 
says : " It would be worse than a mistake to uproot it and 
make it a mere unit in the fortuitous concourse of atoms 
known as the Science and Art Museum at South Kensing- 
ton. ... If technical education is to be encouraged 
our museums must be multiplied and made more accessible 
to the many, instead of being diminished or concentrated 
in a suburb where they can only be a luxury of the few." 

On Monday, the 7th May, the Council of the Royal 
Geographical Society awarded one of the two medals 
to Dr. Sven Hedin for his work in Central Asia, and 
especially for his survey of the glaciers of Mustagata. The 
Doctor was the first explorer to cross the Tal<la-Makan 
desert, and has done much good work in further advancing 
our knowledge of the physical geography of the Lob region. 
The other medal was awarded to Lieut. E. A. Peary, for 
his explorations in Northern Greenland, begun twelve years 
ago, and especially for his sledge journey across the Green- 
land ice, and the discovery of its northern termination. 

We understand that the valuable collection of meteorites 
formed by Mr. James R. Gregory is to be disposed of as a 
whole. As the collection includes about five hundred 
specimens, rich in fine examples of the earlier " falls,' and 
has occupied nearly forty years in the compilation, it might 
be a useful acquisition for some museum. 

The Royal Photographic Society's Exhibition at the 
Crystal Palace was a great success, and almost all branches 
of photography were well represented. The most striking 
feature of the exhibition was the degree of perfection 
which photography has attained as an art, many beautiful 
enlargements being " as good as pictures. " Photography, 
as applied to science, was in quality excellent, but one 
would like rather more of it. A few choice astronomical 
subjects (the eclipse being well shown), also a fair pro- 
portion of photomicrographs and radiographs, deserved 
careful study. There svere, too, some very successful flash- 
light photographs in coal mines, and a marvellous panoramic 
view from a balloon taken by means of the telephoto lens. 



Ornithological Notes. — Owing to the absence from 
England of Mr. Harry Witherby, these have to stand over 
until next month. 



AFRICA AND ITS ANIMALS. 

By E. Lydekker, b.a., f.r.s. 

IF we take'a map of the world, and, after tracing upon a 
sheet of thin paper the outline of the British Islands, 
cut out the tracing and lay it upon India, we shall 
find that it covers a mere patch of that great area. 
Repeating the same process with India, and placing 
the tracing thus obtained on Africa in such a manner that 
the sharp angle on the tracing formed by Assam overlies 



the projecting point of Somaliland, which it almost exactly 
covers, it will be found that the area embraced in the 
tracing occupies only a small patch in the middle of the 
eastern side of the Dark Continent. As a matter of fact, 
the patch thus marked out ends in a blunt point north- 
wardly some distance above Khartum, thence it runs south 
to the neighbourhood of the Victoria Nyanza, from which 
district it rapidly narrows to teiminate in a sharp point 
some distance to the southward of Zanzibar. Allowing 
for some slight overlaps, no less than six Indias can be 
traced on the map of Africa ; and as these leave between 
them and on their margins considerable spaces of the 
country still uncovered, it would be but a moderate esti- 
mate that Africa includes at least seven times the area of 
British India. Some idea, especially to those familiar 
with our vast Indian dominions, may in this manner be 
most readily gained of the huge extent of the African 
continent. 

Having made these comparisons of the actual size 
of the three areas under consideration, I must ask my 
readers to regard them for a moment from another point 
of view. Everyone famihar with the birds and mammals 
of the British Isles is aware that, even excluding Ireland, 
'the same species are not found over the whole area. The 
Scottish hare, for instance, is specifically distinct from the 
ordinary English kind, while the red grouse is unknown 
in the southern and eastern counties of England, and the 
ptarmigan is confined to the colder districts of Scotland. 
There are accordingly indications that even such a small 
area as the British Isles contains local assemblages of 
animals, or faunas, difiering more or less markedly from 
those of other districts. 

Turning to India, we find such local faunas — as might 
be expected from its larger area — more distinctly defined, 
and more markedly different from one another. One great 
fauna occupies the southern slopes of the Himalaya from 
the base to about the upper limit of trees ; this fauna, 
which includes many peculiar types unknown elsewhere, 
being designated the Himalayan. The second, or typical 
Indian fauna, occupies the whole of India from the foot 
of the Himalaya to Cape Comorin, exclusive of the Malabar 
coast, but inclusive of the north of Ceylon. The third, or 
Malabar fauna, occupies the JIalabar coast and some of 
the neighbouring hills, together with the south of Ceylon ; 
the animals of these districts being very different fi-om 
those of the rest of India. The fourth, or Burmese fauna, 
embraces only the province of Assam, in what we commonly 
term India ; and many of its animals, again, although of 
the general Oriental type, are very different from those of 
the other districts. But even such divisions by no means 
give the full extent of the local differences between the 
animals of the whole area. In the second or typical area, 
for example, the creatures inhabiting the open districts of 
the Punjab and the North-West Provinces display remark- 
able differences from those dwelling in the forests of 
Southern India (the home of the strange loris) ; while the 
dwellers in the jungly tract of the south-western districts 
of Bengal are equally distinct from those of either of the 
other areas. 

Seeing, then, that while slight differences are observable 
in the local faunas of such a small area as the British 
Islands, and that much more important ones characterize 
the different zoological provinces of the vastly larger 
extent of country forming British India, it is but natural 
to suppose that distinctions of stiU higher value would be 
characteristic of different parts of Africa, accordingly as 
they difl'er from one another in climate, and consequently 
in vegetable productions. 

As a matter of fact such differences do occur to a most 



138 



KNOWLEDGE. 



[Ji-NE 1, 1898. 



marlied degree ; but when the vast superiority in size of 
Africa over India is taiten into consideration, the marvel is 
that the fauna of the greater part of that area is not more 
dissimilar than it is, and that it has been found possible 
to include the more typical portion of the continent in one 
great zoological region or province. 

But the reader will naturally inquire what is meant by 
calling one portion of a continent more typical than the 
rest. As has been pointed out in an earlier article in this 
journal,* Northern Africa has, so far as its animals are 
concerned, been cut off from the districts lying south of 
the Tropic of Cancer by the great barrier formed by the 
Sahara : and as the animals of the districts to the north 
of that desert are for the most part of a European type, 
while Southern Europe and Northern Africa were evidently 
joined by land at no very distant epoch of the earth's 
history, the districts north of the Sahara are for zoological 
purposes regarded as part of Europe and Asia. Typical, 
or Ethiopian Africa, as it is more generally termed, 
includes, therefore, only such portion of the continent as 
lies to the south of the northern tropic. 

But the critical reader may perhaps here be led to 
remark that some at least of the animals of Northern Africa 
are common to the South ; the lion, whose range extends 
from Algeria to the Cape, affording a case in point. To 
this it may be replied that, popular prejudice notwith- 
standing, the lion cannot in any sense be looked upon as 
a characteristic African animal. Although year by year 
growing rarer, it to this day still lingers on in certain parts 
of Western India, while it is likewise found in Persia and 
Mesopotamia, and within the historic period was common 
in South-Eastern Europe. At a still earlier epoch, as 
attested by its fossilized remains, it was an inhabitant of 
our own island. It may, therefore, to a certain degree be 
regarded as a cosmopolitan animal, which may have 
obtained entrance into Africa by more than one route. 
In a minor degree the same may be said of the hippo- 
potamus, which was formerly found in the lower reaches 
of the Nile, and at a much earlier epoch in many parts of 
Europe, inclusive of Britain. Being an aquatic animal, 
it can avail itself of routes of communication which are 
closed to purely terrestrial creatures. 

Of the fauna of typical Africa, as a whole, some of the 
most striking features are of a negative nature ; that is to 
say, certain groups which are widely spread in most other 
districts of the Old World are conspicuous by their absence. 
This deficiency is most marked in the case of bears and 
deer, neither of which are represented throughout the 
whole of this vast expanse of country. Pigs allied to the 
wild swine of Europe and India are likewise lacking; their 
place being taken by the bush-pigs and the hideous wart- 
hogs, both of which are among the most characteristic of 
African animals. Except for a couple of species of ibex 
in the hills of the north-east, sheep and goats are likewise 
unknown in a wild state. Among other absentees in 
the fauna, special mention may be made of marmots, and 
their near allies the susliks, as well as of voles, beavers, 
and moles. 

Of the mammals (and space permits of scarcely any 
reference to other groups) which may be regarded as 
characteristic of typical Africa as a whole, the following, 
in addition to the bush-pigs and wart-hogs already men- 
tioned, are some of the most important. Among the 
monkeys the most widely distributed are the hideous 
baboons (Papio), now restricted to Africa and Arabia, the 
southern portion of the latter country being included 
in the same great zoological province. The guenons 

* "Deserts and tbeir luhabitants,' Knowledge, May, p. 101. 



(Cercojjitheais), species of which are the monkeys commonly 
led about by organ-grinders, have also a wide distribution 
on the continent, although of course more abundant in the 
forest regions than elsewhere ; and the gnerez&s {(^<l>jbm), 
one of which was described some months ago in Know- 
ledge, ' have also a considerable range. In a totally different 
group, the curious little jumping shrews (Macroscelides) 
form a peculiarly characteristic family of African mammals 
belonging to the insectivorous order. There are also 
many peculiar genera of mungooses, but as most of these 
have a more or less local distribution they can scarcely 
be considered characteristic of the continent as a whole ; 
still, they are quite different from those found elsewhere. 
A very curious carnivorous mammal known as the aard- 
wolf (Proteles), strikingly like a small striped hyaena, is 
not the least peculiar among the animals of Africa, where 
it has a comparatively wide range. The hunting dog 
(Li/caiDi), which presents a considerable resemblance ta the 
spotted hyicna, is an equally remarkable representative of 
the dog family. Although formerly found In Europe, the 
spotted hyipna itself is now exclusively African. 

Passing by the rodents, or gnawing mammals, as being 
less familiar to non- zoological readers, we have the two 
species of hippopotami absolutely confined to Africa at the 
present day ; we are all familiar with the common species 
in the " Zoo," but the small West African kind, which has 
more the habits of a pig, is much less commonly known. 

The stately giraffes are solely African, but appear to 
be mainly confined to the more open districts. The herds 
of antelopes, for the most part belonging to generic types 
unknown elsewhere, with the exception of a few in Arabia, 
form one of the most distinctive features of African life. 
Many of them, like the strange gnus and the graceful 
gemsbok group, are confined to the open districts of the 
south and east; but others, such as the bush-bucks and the 
harnessed antelopes, have representatives in the forest 
districts of the west, lioth species of African rhinoceros 
are quite different from their Oriental relatives, but only 
one of these, the common species, has a wide distribution 
in the country. Zebras, and the now extinct quagga, are 
familiar and striking African animals, although they are 
confined to the open plains and mountains. On the other 
hand, the African elephant, which differs so widely in the 
structure of its teeth from its Asiatic relative, has a 
much more extensive distribution, and may therefore be 
classed among the most characteristic of Ethiopian 
animals. Even more peculiar are the little hyracea 
(Prociivia), the miscalled coneys of our version of the Bible, 
which form a family absolutely peculiar to Africa, Arabia, 
and Syria ; some of the species dwelling among rocks, 
while others are active climbers, and frequent the forest 
districts. But perhaps the strangest mammal that may be 
regarded as characteristic of Africa as a whole is the 
aard-vark (onjcteritpus), commonly known to the colonists 
as the ant-pig. It is a strangely isolated creature, having 
at the present day no near relations, either poor or 
otherwise. 

The African buffaloes, with their several races or species, 
also belong to a type quite peculiar to the continent. To 
a great extent the ostrich is characteristic of Africa and 
Arabia, although there is evidence to show that it formerly 
enjoyed a considerable range in parts of .^sia. 

The above are only a few of the more striking instances 
showing how different are the animals of Africa as a whole 
from those of the rest of the world. Many others might be 
added, but they would only weary my readers. Of coarse, 
there are many groups, like the cats, common to other 



• June. 1897. p. 130. 



June 1, 1898.] 



KNOWLEDGE 



1?.9 



countries, the lion and the leopard being found alike in Africa 
and India ; but auch do not detract from the peculiarity of 
the African fauna as a whole. And here it may be mentioned 
that a large proportion of the types now peculiar to 
the Dark Continent appear to have come from India or 
some adjacent country, fossil remains of baboons, giraffes, 
hippopotami, ostriches, antelopes of an African type, and 
not improbably zebras, having been discovered in the 
Tertiary deposits of India. 

But if the animals of Africa as a whole stand out in 
marked contrast to those of the rest of the world, much 
more is this the case when those characteristic of certain 
districts of that huge continent are alone taken into 
consideration. And most especially is this so with the 
inhabitants of the great tropical forest districts extending 
from the west coast far into the interior of the continent — 
reaching, in fact, the watershed between the basins of the 
Congo and the Nile in thu neighbourhood of Wadelai. 
Since a large number of the peculiar animals of this district 
are more or less exclusively confined to the west coast, 
extending from Sierra Leone to the Congo, the area is 
appropriately termed the West African sub-region. It is 
here alone that we find the gorilla and the chimpanzee, 
the former being restricted to the neighbourhood of the 
coast, whereas the latter ranges far into the heart of the 
continent. And this district is likewise the exclusive 
home of the pretty little mangabys, or monkeys with 
white eyelids (Cercdcelnni). The galagos, which are near 
relatives of some of the lemurs of Madagascar, extend 
throughout the forest region ; but the even more curious 
pottos, or thumbless lemurs, are confined to the west coast. 
Huge and forbidding fox-bats, some of them with remark- 
able tufts of long white hairs on the shoulders, are likewise 
restricted to this portion of the tract, as is the insecti- 
vorous otter, or Potumoijale, first discovered during the 
travels of Du Chaillu. The equatorial forest tract is also 
the sole habitat of the African tiyiug squirrels, distinguished 
from the very different flying squirrels of Asia by the 
presence of a number of scales on the under surface of the 
tail. Most of these belong to the genus Anomnluni.s, but 
the smallest of all forms a genus {[diurus) by itself, and 
will be familiar to readers of this journal by a life-sized 
portrait published some years ago. Dormice of peculiar 
types and tree mice are also very characteristic of this 
tract. But far more generally interesting are the pigmy 
hippopotamus of Liberia and the water chevrotain (Dorca- 
tlieriuw) of the west coast, an ally of the true chevrotains 
of India and the Malay countries. So far, indeed, as the 
equatorial forest tract fauna has any representative in 
other parts of the world, it is to the Malay peninsula 
and islands that the resemblance is closest. It is there 
alone that the other large manlike ape — the orang — 
dwells ; and there is a group of brush-tailed porcupines 
common to these two districts, and unknown elsewhere 
throughout the wide world. Both faunas, however, in all 
probability trace their descent from the animals inhabiting 
Europe during the Pliocene and Miocene epochs, among 
which was an extinct species of water chevrotain. 

The other great sub-regions include the open grazing 
grounds and mountains of South and East Africa, the fauna 
of which is quite different from that of the equatorial forest 
tract. Minor divisions may also be recognized in this area, 
the Cape having many animals not found further north. 
Among the latter are the so-called white rhinoceros, the 
pretty little meerkat(.SK?uY(f«), the long-eared fox ((Jtocyon), 
and the Cape sand mole (Butliyergux), which, by, the way, 
has nothing to do with the true moles, being a member of 
the rodent order. This tract as a whole may be termed the 
east central sub-region ; and to it belong the great hosts 



of antelopes, the zebras, and the aard-wolf and hunting 
dog. Very characteristic of the southern and eastern parts 
of this tract are the beautiful golden moles (C/u-yscldorh), 
unique among mammals for the lovely play of iridescent 
colours on the fur, and which have comparatively nothing 
in common with the moles of Europe and Asia. To 
the northward, in Abyssinia, this tract is the home of 
another very remarkable animal, the great gelada baboon 
{TheropithccHs), easily recognized by the lionhke mantle 
of long hair on the fore quarters, whose nearest relatives 
are the ordinary baboons of Africa. 

Whether Somaliland should be included in this area, or 
should have a division to itself, may admit of argument ; 
but at any rate it has many peculiar animals, among 
which are a number of antelopes, some of which have but 
recently been made known to science. 

Lastly we have the Saharan sub-region, which contains a 
comparatively limited fauna, passing by almost insensible 
degrees into that of Northern Africa. 

In some respects, especially in its galagos, the fauna 
of Africa presents a certain resemblance to that of 
Madagascar ; but the connection between that island and 
the mainland was evidently very remote, and must have 
taken place before the great incursion of antelopes, zebras, 
rhinoceroses, monkeys, elephants, etc., from the north, as 
none of these are found in the island. Madagascar, there- 
fore, is best regarded as forming a zoological province by 
itself. 

Within the limits of a single article it is manifestly 
impossible to give aaything like an adequate sketch of the 
fauna of such an extensive area, but such points as have 
been noticed serve to sho'.v in some faint degree its rich- 
ness in peculiar forms of animal life. 



THE VINEGAR FLY AND THE VINEGAR MITE. 

By C. AiNswoRTH Mitchell, b.a., f.i.c. 

THE vinegar eel, of which a description appeared in 
a recent number of Knowledc-e (page 53), is not 
the only creature with a marked partiality for 
vinegar, for two other animals have become so 
associated with its manufacture that they are 
known as the vinegar fly and the vinegar mite. 

The vinegar fly [DrosophUa funebris) is of very common 
occurrence, and may be found in any vinegar works during 
the hotter months of the year. It is about a tenth of an 
inch in length, and is characterized by large red eyes, red 
thorax, and red legs. The abdomen is black with yellow 
stripes, and the wings are somewhat longer than the body. 
According to Brannt the larva is white, has twelve seg- 
ments to its body, and four wart-like structures on its 
back, two of these being yellow. After eight days it is 
transformed into a yellow chrysalis. 

Vinegar makers are not in the habit of paying much 
attention to the presence of the vinegar fly, since, as far as 
is known, it does not in any way aflect the manufacture ; 
and it is readily prevented from becoming a nuisance by 
keeping the works thoroughly clean and not allowing any 
spilt vinegar to lie about on the ground. 

The vinegar mite, unlike the fly, must be regarded as a 
distinct enemy to the acetic bacteria, though not, perhaps, 
to the same extent as the vinegar eel. When once it has 
obtained a footing within an acetifier it multiplies with 
amazing rapidity, interferes with the oxidation process, 
and is not easily exterminated. Dr. Bersch describes the 
state of an Italian factory about which he was consulted 
in 188L Every drop of vinegar produced contained one 
or more of these mites, which were present in myriads 



140 



KNOWLEDGE 



[June 1, 1898. 




Flo. 1. — From the under 
side. X 120 diameters. 
After Bersch. 

At first the acetic 



on every part of the acetifiers, and which finally had 
brought the manufacture to a complete standstill — the 
manufacturer being unable to account for their presence 
beyond stating that they were derived from the soil beneath 
his apparatus. 

In its simplest form an acetifier consists of a large vat 
with a perforated false bottom. The space above this 
is filled with shavings or other porous material on which 
the bacteria settle, and the alcoholic liquid is pumped over 
and over through the shavings until the whole of the 
alcohol has been converted into acetic acid. The necessary 
air is admitted through holes made in the side of the vat, 
whilst smaller holes at the top allow the waste air to escape. 
Many modifications of this apparatus are in use, in which 
means are taken to exactly regulate the air supply and 
the temperature ; but it is in this simple form, as first 
invented by Sehiitzenbach in 1823, that most of the 
acetifiers in England and Germany are constructed. Prior 
to Schiitzenbach's invention, which 
is still known as the " quick vinegar 
process," vinegar was made by 
placing the alcoholic liquid with a 
little vinegar containing the bacteria 
in barrels, which were turned and 
aiirated from day to day by work- 
men. It is through the holes for 
aurating the acetifier that the 
vinegar mite finds its way into the 
interior, and attempts have been 
made to prevent this by placing 
birdlime round the outside of the 
holes, whilst in some of the more 
recent patents fine wire gauze 
is employed for the same purpose 
bacteria do not appear to be much affected by the presence 
of the mites, but as these increase and then die ofl' and fall 
to the bottom their dead bodies begin to putrefy, and the 
putrefaction bacteria or their products sooner or later have 
an injurious effect, and if not removed will eventually 
completely master the acetic bacteria. 

The vinegar in which the mites have thus gained the 
upper hand has a peculiar 
yellowish shade, and con- 
tains what appear to the 
naked eye to be a large 
number of white specks. 
When examined under the 
microscope these have the 
appearance shown in Figs. 1 
and 2. 

These two forms, appa- 
rently those of the male and 
female, are always found, 
many of the individuals 
being only one quarter or 
one half of the size of the 
others. Bersch assigns 
them to the class of Sarcop- 
tidce, but little appears to be known about their life history. 
When once vinegar mites have established themselves 
within an acetifier they can only be expelled by destroying 
them simultaneously with the acetic bacteria. For this 
purpose the vat must be emptied of vinegar as completely 
as possible, and the interior thoroughly washed with hot 
water, well fumigated with burning sulphur until all Ufe 
is destroyed, and then washed again. It is then charged 
afresh with the alcoholic liquid and a little crude vinegar 
containing the bacteria, but of course it is some time 
before the apparatus gets into working condition again. 




FiQ. 2 



; 120 diameters. 
Bersch. 



A CLASSIC LEGACY OF AGRICULTURE. 

By John Mills. 

ALL great discoveries are the result of much study, 
and often arise out of those truths of science which 
appeared least promising on their first announce- 
ment. The time is past when practice can go on in 
the blind and vain confidence of a shallow em- 
piricism, severed from science like a tree from its roots. 
Scientific principles are now extensively applied in problems 
concerned with the improvement of the artificial means em- 
ployed for increasing the fertility of the soil. During the 
last sixty years, more especially, the transmuting power of 
the " philosopher's stone " has been displayed, and many 
triumphs have been achieved through the painstaking re- 
searches of men who, like Sir John Lawes and Sir Henry 
Gilbert, are not content to adhere strictly to the role-of- 
thumb methods which have been in vogue for untold ages. 
Agriculture is both an art and a science. On the 
scientific side chemistry plays an important part, and is 
called into request for the investigation of the composition 
of soils, manures, and of the vegetable and animal sub- 
stances which it is the aim of agriculture to produce. All 
the conditions of the life of vegetables, the origin of their 
elements, and the sources of nourishment, are secrets which 
can be elicited by the aid of science. Given a barren tract 
of country, which has been unproductive from generation 
to generation, the scientific agriculturist will improve the 
parts by transporting and transposing the different soils. 
The analysis of the soils will be followed by that of the 
waters which rise or flow through them, by which means 
he will discover those proper for irrigation. A knowledge 
of chemistry teaches us when and in what condition to 
use lime, and the difference in the properties of marl, peat, 
dimg, mud, ashes, alkali, salt, soap-waste, sea-water, etc., 
and consequently which to prefer in all varieties of soil— 
a knowledge which thus imparts a new character to the 
agriculturist, and renders his emploj'ment rational. 
Environed by an endless variety of processes and results, 
scientific agriculture is constantly disclosing surprises. 
The nineteenth century has witnessed developments greater 
than those of all previous time. It is as true to say now 
that agriculture is in a state of transition and development 
as it was a century ago to say it was in a state of inanition 
and even stagnation. The position of agriculture is now 
hopeful, for the age is progressive. It is a period of 
adaptation, of new departures, new energy, and greater 
economy. Foreign competition is understood and expected. 
To know what it is provides the means of meeting it. 

We purpose m this article to afford a glimpse of the 
artificial aids to agriculture which Sir John Lawes and 
Sir Henry Gilbert have for upwards of fifty years practised 
at the Rothamsted Agricultural Experimental Station — 
the model of all agricultural stations, and the methods 
there introduced are everywhere regarded as classical. The 
researches carried on by these coUaborators have elicited 
information which will ever serve as the foundation of a 
truly scientific knowledge of the correlation of plant- 
growth and manurial constituents of the soil, and will be 
of the utmost value in all discussions of the chemistry of 
plant Ufe. The immense number of exact data which they 
have placed at the disposal of chemists is without parallel 
in the annals of science. As Sir Joseph Hooker has said, 
in the whole history of science, never have two of its 
greatest divisions been brought into more profitable cor- 

• We are much indebted to both Sir John Lawes, Bart., f.b.s., 
and Sir Henry Gilbert, f.e.s., for generous assistance in explaining 
the arrangement of the experimental plots at Rothamsted, the 
conduct of the laboratory, and in placing records, etc., at our disposal 
in preparing this article. 



June 1, 1898.] 



KNOWLEDGE 



141 



relation than chemistry and botany have been in the 
Rothamsted esperimeuts. The far-seeing intelligence which 
devised the details affords results which have completely 
reformed the practice of agriculture, and the carrying on 
of a single research without interruption during a period of 
over fifty years is unexampled — a research which has 
taught those concerned how to estimate the actual mean 
fertility of the earth's surface, and, in the subordination 
of permanent pasture to the practical advantage of the 
farmer, to successfully employ readily available chemistry 
to modify at pleasure the entire character of the vegetation. 

Sir John Lawes, apart from his acientilic researches in 
conjunction with Sir Henry Gilbert, is probably the oldest 
practical farmer in England, and inherited all the traditions 
of a long ancestry, so that he may truly be regarded as an 
adherent to the motto, " Practice with science." The 
manor house of Rothamsted is situated in the midst of a 
beautifully wooded park, at Harpenden, near St. Alban's, 
and the experimental grounds are in the estate adjoining 
the park. Sir John first commenced operations in 1834, 
soon after succeeding to his property, first with plants in 
pots, and afterwards in the fields, using different manuring 
substances. The researches of De Saussure on vegetation 
were the chief subject of his study to this end. The 
most striking results were obtained by the use of neutral 
phosphate of lime, in bones, bone-ash, and apatite, 
rendered soluble by means of sulphuric acid. The mixture 
so obtained answered well for root-crops. In 1813, 
the date at which the researches commenced in real 
earnest, and when Dr. (now Sir Henry) Gilbert entered 
into the work, more systematic field experiments were 
initiated. These researches relate not only to the growth 
of cereal and other crops under the most varying conditions, 
but also to the economic effect of different foods on the 
development of the animals of the farm. They have 
embraced, moreover, most important researches concern- 
ing the sources from which plants derive their supply of 
nitrogen. 

Following in the wake of the Rothamsted experiments, 
Germany has worked in the same field, and to-day she can 
number twenty-five experimental stations, which institute 
both scientific researches and deal with their adaptation to 
practice. Germany is indebted to experimental stations 
for the progress she has made during the last decade, 
especially in agriculture. Yet while the German stations 
have been founded by associations of agriculturists and 
maintained at the public expense, the Rothamsted experi- 
ments are due to the activity of two eminent men, and are 
maintained by private funds ; from the commencement 
they have been entirely disconnected from any external 
organization, and have been maintained at the sole cost of 
Sir John Lawes. For the continuance of the investigations 
after his death, Sir John has made the munificent endow- 
ment of one hundred thousand pounds, besides the famous 
laboratory and certain areas of land, and has nominated 
some of the most distinguished scientific men of the day 
to administer the trust. 

While it is a fact, affording some cause for self-satis- 
faction, that the farmers of Great Britain grow a larger 
produce per acre than the farmers of any other country in 
the world (the average yield of wheat per acre in 1888 
was twenty-eight bushels, while that of the United States, 
for example, was eleven bushels), it is a noteworthy fact 
in connexion with these investigations that they have not 
been of the same benefit to our own nation as they have 
to some other nations. Thus, while, as in the case of 
Germany, Government has come to the aid of agricultural 
research to a praiseworthy extent, enterprise in this country 
is carried on by private resources, save in the college at 



Glasnevin, near Dublin, to which a Government grant is 
allotted; the colleges at Cirencester, Downton, and the 
Colonial Training College in Suffolk, being self-sup- 
porting, and these all draw to a considerable extent upon 
the researches at Rothamsted for exact information. 

The investigations were commenced upon truly orthodox 
lines, and with truly orthodox views ; but as it was not 
possible to alter the laws of nature, it was soon found that 
the results brought out did not agree with the views of the 
recognized authorities of the day. Among other things it 
soon became woefully apparent how small after all was 
the available leverage for artificially assisting the processes 
of nature. Too conspicuous to be mistaken, the weather 
announced itself as the great factor in producing crops. 
Every day in the year makes its impression, good or bad, 
on the final issue, which appears to be something very like 
the algebraic sum^the positive and negative result of the 
favourable and unfavourable weather of all the days in the 
year leaving us the victims of circumstance in spite of aU 
the refinements of science. These investigators also saw 
clearly the explanation of an experiment which Hale per- 
formed more than two hundred years ago. Hale had 
carefully tended a plant in a pot, and noticed that, although 
the soil lost very little in weight, the plant increased by 
an amount tremendously in excess of that lost by what 
appeared to be the parent soil. Whence came, then, the 
elements of the plant ? The Rothamsted experiments show 
clearly that about ninety-five per cent, come from the 
atmosphere, and only some five per cent, from the soil, 
thus driving home Dumas' saying that " at last analysis 
we are nothing but condensed air. " 

Some idea of the magnitude and importance of the 
researches carried on at Rothamsted may be gleaned from 
the list of field experiments given in the accompanying table. 



Crops. 


Duration. 


Area. 


Plots. 




Tears. 


Acres. 




Wheat (rarious manures) 


54 


11 


34 (or 37) 


Wheat, alternated with fallow 


46 


1 


2 


Wheat (varieties) ... 


15 


4-8 


about 20 


Barlev (various manures) 


46 


a 


29 


Oats (various manures) 


10* 


i 


6 


Beans (various manures) 


32t 


U 


10 


Beans (various manures) 


27: 


1 


5 


Beans, alternated with Wheat .. 


28 § 


1 


10 


Clover (various manures) 


2911 


3 


18 


Various Legimiinous Plants . . . 


20 


3 


18 


Turnips (various manures) 


281 


8 


40 


Susar Beet (various manures)... 


5 


8 


41 


Mangel- Wurzel (various 








manures) 


22 


8 


41 


Total Root Crops ... 


55 





Potatoes [various manures) 

Rotation (various manures) 

Permanent Grass (various 

manures) 



* Includinsr one year fallow. 

t Including one year Wheat and five years fallow. 

j Including four years faUow. 

§ Inclading two years fallow. 

" Clover, twelve times sown (first in 1848), eight yieldi:^ crops, bnt fonr 
>f these very small, one year Wleat, five years Barley, twelve years fallow. 

■" Including Barley without manure three years (eleventh, twelfth, and 
hirteenth seasons). 



Many of the experiments were commenced without any 
idea of long continuance, and it was only as the results 
obtained indicated the importance of such continuance 
that the plan eventually adopted was gradually developed. 
It is, however, to long continuance that we owe some of 
the most interesting and the most valuable results. 



142 



KNOWLEDGE. 



[JrxE 1, 1898. 



The table further shows the area and the number of 
plots under experiment in each case ; and it may be stated 
that the total area under exact and continuous experiment 
has been for some years, and is at the present time, about 
forty acres. 

To cultivate and simultaneously investigate scientifically 
the products of such an extensive series of plots of ground, 
a staff of workers of no mean order is of course necessary. 
A number of general assistants, therefore, are engaged to 
superintend the field experiments— that is, the making of 
the manures, the measurement of the plots, the application 
of the manures, and the harvesting of the crops ; also the 
taking of samples, the preparation of them for analysis or 
preservation, the determination of dry matter, ash, etc., 
and the keeping of the meteorological records. There is a 
permanent laboratory stafl' of two, and sometimes three, 
chemists, and three or four computers and record-keepers 
for calculating and tabulating field, feeding, and laboratory 
results, copying, etc. In addition to a large staff of this 
kmd, the best professional assistance has been called in 
from time to time. Among these may be mentioned Prof. 
Frankland, who determined the nitrogen as ammonia, as 
nitric acid, and as organic nitrogen in many samples both 
of the rain and of the various drainage waters collected at 
Rothamsted; Prof. \V. J. Russell estimated the sulphuric 
acid in some of the monthly mixed samples of rain water ; 
the late Dr. Voelcker determined the nitrogen, and likewise 
the incombustible constituents, in sixty-five samples of the 
drainage waters ; Dr. Richter has made more than eight 
hundred analyses of the ashes of various products, animal 
and vegetable, of known history ; and the late Dr. Pugh 
took a prominent part in the experiments to determine 
whether plants assimilate free nitrogen, and also various 
collateral points. 

Samples of all the experimental crops are taken and 
brought to the laboratory. Weighed portions of each are 
partially dried, and preserved for future reference or 
analysis. Duplicate weighed portions of each are dried at 
100° C, the dry matter is determined, and it is then burnt 
to ash on platinum sheets in cast-iron mufHes. The 
quantities of ash are determined and recorded, and the 
ashes themselves are preserved for reference or analysis. 
In a large proportion of the samples the nitrogen is deter- 
mined ; and in some the amount existing as (dbumimids, 
iimidfs, and nitric acid. There is now a collection of more 
than forty-five thousand bottles of samples of experimen- 
tally grown vegetable produce, of animal products, of ashes, 
or of soils, besides some thousands of samples not in 
bottles ; and the laboratory having become very incon- 
veniently full, a new detached building — a " sample house " 
— was erected in the autumn of 1888, comprising two 
large rooms for the storing of specimens and for some 
processes of preparation, and also a drying room. 
The general scope and plan of the field experiments 
has been to grow some of the most important crops of 
rotation, each separately, year after year for many years 
in succession on the same land, without manure, with 
farmyard manure, and with a great variety of chemi- 
cal manures ; the same description of manure being, 
as a rule, applied year after year on the same plot. 
Experiments on an actual course of rotation without 
manure, as well as with different manures, have also been 
made. 

Having thus indicated the scope of the researches at 
Rothamsted, the resources available, and the disposition 
of the estate, we shall endeavour in a subsequent article 
to present some of the remarkable results which have been 
derived therefrom, and the bearing of the conclusions 
arrived at on practical agriculture. 



NOTES ON COMETS AND METEORS. 

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

Lewis Swift. — The famous American astronomer, Lewis 
Swift, well known for his discoveries of nebulae and 
comets, furnishes a remarkable example of the retention 
of brilliant observational capacity to an advanced age. 
Though the time of his birth dates back to 1820, Feb- 
ruary 29th, he still discovers numbers of exceedingly faint 
nebuhr, and occasionally announces a new comet. The 
most recent of his cometary discoveries was in 1896, April, 
when he was in the seventy-seventh yi'ar of his age ! His 
success has certainly been astonishing. No other comet- 
finder appears to have effected discoveries at a period so 
late in life as the veteran of whom we are speaking. Pons 
was about sixty-six years old, Mechain fifty-five, and 
Messier sixty-eight, when they sighted their last comets. 
Let us hope that Swift will yet be spared some years to 
add to his laurels by the discovery of further objects in 
the fields where he has already laboured so long and with 
so much distinction. 

Feriine'ti Comet (Marfh 19th). — This object is still 
visible, though becoming very faint. At the early part of 
June its brightness will be only one-fifth that at discovery. 
\n ephemeris was given in the last number of Knowledge. 

Periodical ( omets. — The comets of Wolf, Encke, and 
Tempel (1867, II.), are shortly expected to appear, but 
the circumstances are not favourable. Pons-Winnecke's 
comet is now exceedingly faint. The following are ephe- 
merides : — 

Comet Wolf. 











distance in 






RA. 


Durliuatiuu. 


millions of 


Date. 


h. 


m. s. 


o 


miles. 


June o 


1 


36 19 


-f 18 33-0 


204 


,. 11 


1 


59 58 


+ 19 190 


199 


,, 19 


2 


23 18 


-f 19 51-3 


194 


„ 27 


2 


17 43 
Comet 


-h 20 8-7 

ExCKE. 


lOO 


June 1 


11 


7 12 


+ 20 15-5 


82 


„ 10 


6 


16 H 


+ 13 16-6 


60 


„ 14 


7 


1 41 


+ 9 15-8 


51 


„ 18 


7 


18 43 


+ 4 24-2 


44 


„ 22 


7 


38 59 


- 1 38-7 


38 


„ 26 


8 


4 46 


- 9 16-8 


33 


„ 30 


8 


39 19 
Comet Pons 


-18 45-8 

-WiNXECKE. 


28 


June 3 


1 


56 1 


- 1 7-0 


174 


,. 11 


2 


14 26 


- 12-2 


177 


,, 15 


2 


23 3 


+ 11-4 


178 


„ 19 


2 


31 17 


+ 32-3 


179 



June 1 



Comet Tempel (1867, II.). 
11 41 11 +13 501 



177 



Comet Wolf is approaching the earth, but it will not 
come as near as in 1891, and will probably remain a faint 
object during the whole of this apparition. It will reach 
its perihelion on July 4th, though it will continue to 
become very gradually brighter until the close of October. 
Comet Encke is rapidly advancing nearer to the earth 
and its apparent brightness increasing, but its position 
is not favourable for northern observers, as its motion 
carries it very quickly southwards. During the month 
the comet passes from the north-west extremity of Gemini 
to the south-east border of Monoceros. Tempel's comet 



June 1, 1898.] 



KNOWLEDGE. 



143 



will be close to (3 Leonis at the beginning of June, but its 
exact place is doubtful. 

M. Legarde has recently published a new determination 
of the orbit of Tempel's comet of 1871. The comet was 
observed during^an interval of one hundred and nine days, 
and its orbit appears to be that of a very excentric ellipse, 
with a periodic time of about two thousand and thirty 
years. 

The April Meteors. — Prof. A. S. Herschel, at Slough, 
registered the paths of sixty-eight meteors observed on 
clear nights between April 12t,h and 2-tth. The sky was 
hazy on April 19th, and only one uncertain meteor was 
seen in a watch of two and a half hours' duration. On 
April 20th clouds prevailed. Very few, if any, Lyrids were 
observed, but the meteors recorded indicated a large number 
of minor showers in Corvus, Libra, Ursa Major, Draco, and 
the region of Hercules. At Bristol, on April 17th, 18th, 
19th, and 22nd, meteors were found to be somewhat rare, 
and very few Lyrids were noticed. Four of the meteors 
observed at Bristol were also recorded by Prof. Herschel 
at Slough, but in two cases the observations do not match 
very well, as the meteors were very indifferently seen at 
Bristol. Of the other two, one appeared on April 17th, 
lOh. 28m. It was a small, very slow moving meteor, with 
a radiant near the southern horizon. Its heights were 
from seventy-two to seventy miles over Malmesbury to 
Evesham, and it traversed a path of about thirty-four miles. 
The other was seen on April 22nd, lOh. 32m. It was 
directed from a radiant at 252^ -(-49^, and fell from a 
height of seventy-two to fifty-two miles from above Alcester 
to Malvern. 

The brighter meteors seen by Prof. Herschel were as 
under : — 

Path. 

, Diirutiou 

Date. Time. Mag. v K.A. Dec. K.A. Dec. in 

b. m. o o o o Seconds. 

April 16 10 47 1 290 +52 to 327 +52 25 

,.16 11 27 1 92.i +44 „ 91 +37 04 

„ 17 9 38i 1 44+73 „ 61 +60 10 

„ 19 9 53 1 280 +61 „ 286 +55 8 

„ 23 12 43 1} 158 +30 „ 138 ■^37 2-2 

„ 23 12 48i 1 232^ - 5 „ 231 +1 0-4 

Mr. W. E. Besley, of Westminster, watched the sky on 
April 21st and 22nd during an aggregate period of three 
and a quarter hours, and recorded twenty meteors, of 
which twelve were Lyrids. The principal radiant appeared 
to be very well defined at the usual position, viz., 273~ + 3:5 \ 

If observers at other places noted any of these objects 
the data would be valuable as affording the materials for 
computing their real heights in the atmosphere. 

Fireball of April 5th. — Mr. G. N. Stretton's description 
of this object, as observed at Fulham (Knowle»&e, May, 
p. 114), agrees remarkably well with the radiant point at 
121" — 1'. As seen by your correspondent, the meteor 
must have ascended in a perfectly vertical course ; but if it 
actually reached the zenith, as he remarks, then the place 
I gave for the disappearance must be shifted some 
miles to the north-east, and the height at disappearance 
must have been a little less than that stated. But in 
discussing and endeavouring to harmonize materials of 
this character, one has to adopt the path which best 
satisfies the majority of the observations. Mr. Stretton's 
position was evidently very near the point of the meteor's 
disappearance. The fact that at Bournemouth it fell 
vertically downwards in north-east, while at Fulham it 
ascended straight up to the zenith from south-west, affords 
the clearest proof that the direction of flight of the meteor 
was on a line joining those two places, and that it succes- 
sively passed over Bournemouth, Southampton, Alton, and 
Aldershot, as stated in my paper in your May Number. 



THE FACE OF THE SKY FOR JUNE. 

By Herbert Sadler, f.b.a.s. 

GROUPS of, and small detached, spots are still to be 
detected on the solar surface. 
Mercury is, theoretically speaking, a morning 
star, but cannot be conveniently observed for any 
practical purpose by the amateur during the month, 
owing to his proximity to the Sun. He is in superior 
conjunction with that luminary on the 30th. 

Venus is an evening star, and is conveniently situated 
for observation. On the 1st she sets at lOh. 17m. p.m., 
with a northern declination of 24^ 42' at noon, and an 
apparent diameter of Hi . On the 11th she sets at 
lOh. 26m. P.M., with a northern declination at noon of 
23" 42', and an apparent diameter of 12 ". On the 18th 
she sets at lOh. 24m. p.m., with a northern declination at 
noon of 22' 19', and an apparent diameter of 12^ '. On 
the 23th she sets at lOh. 18m. p.m., with a northern 
declination of 20' 27' at noon, and an apparent diameter 
of 12^'. -On the 30th she sets at lOh. 15m. p.m., with a 
northern declination at noon of 18' 51', and an apparent 
diameter of 13". During the month she describes a direct 
path through a great part of Gemini into Cancer. 

Mars is practically invisible. 

•Tupiter is an evening star, and is still well placed for 
observation. On the 1st he rises at Ih. 16m. p.m., with a 
northern declination of 1" 9' at noon, and an apparent 
equatorial diameter of lOi". On the 11th he rises at 
Oh. 35m. P.M., with a northern declination at noon of 1°, 
and an apparent diameter of 39i". On the 18th he rises 
at Oh. 10m. p.m., with a northern declination of 0' 49', and 
an apparent diameter of 38i". On the 30th he rises at 
llh. 25m. a.m., with a northern declination of 0*^ 24', and 
an apparent diameter of 37i". During the month he 
describes a very short path in Virgo. 

Our remarks last month about the futility of attempting 
to observe either Saturn or Uranus in these latitudes 
apply with equal force to the present month. Neptune is 
invisible. 

There are no very well marked showers of shooting stars 
in June. 

The Moon is full at 2h. 11m. p.m. on the 4th; enters 
her last quarter at 6h. 4m. p.m. on the lith ; is new at 
4h. 19m. A.M. on the 19th ; and enters her first quarter 
at 4h. 54m. a.m. on the 27th. 



Ctjcss CEolumn. 

By 0. D. LooocK, B.A. 
Communications for this column should be addressed to 
C. D. LococK, Burwash, Sussex, and posted on or before 
the 10th of each month. 

Solutwn of May Problems. 
(By P. G. L. F.) 

No. 1. 
1. Q to B5, and mates next move. 
No. 2. 
Key-move. — 1. Q to B3. 
If 1. ... K moves, 2. Q to K2ch, etc. 

1. . . . Anything else, 2. Q to Qsq, etc. 
[There is a near " try " by Q to Qsq at once.] 
Correct Solutions of both problems received from 
Alpha, K. W., Capt. G. A. Forde, W. F. Denning, E. W. 
Brook, W. de P. Crousaz, H. S. Brandreth. 

Of No. 1 only from G. G. Beazley, W. Clugston, 
J. M'Eobert. 

J. Nield fCrumpton). — Many thanks ; we hope to find 
space for them this summer. 



iU 



KNOWLEDGE 



[June 1, 1898. 



PE0BLEM8. 

No. 1. 

By A. C. Challenger. 

Black (If). 



m 







White (7). 

White matea in two moves. 

No. 2. 

By J. T. Blakemore. 

(From the Birminiiham W'eekhi Mercury.) 

BlIck (1»). 




White (j). 

White mates in three moves. 



CHESS I NTELL IGENCE. 

It is with the greatest regret that we learn the news of 
the death of the Kev. W. Wayte, for many years honorary 
treasurer of the St. George's Chess Club, and formerly 
professor of Greek at London University. Prof. Wayte, 
who was for twenty-three years a classical master at 
Eton, was certainly one of the very strongest amateur 
players in England. His knowledge of the whole theory 
of the game was profound, the openings being perhaps his 
especial forte. He was a most successful competitor at the 
annual meetings of the old Counties Chess Association, and 
was captain of the southern team when the North v. South 
contests were instituted. Prof. Wayte was the editor of 
an annotated edition of Plato's " Protagoras," and other 
classical works. His interesting " Chess Reminiscences " 
appeared in the liritish Chess ^[llf/<l:ine (March and April, 
1898). It will surprise many who knew him to find that 
he was in his seventieth year. 

We omitted last month to record the result of the 
Pillsbury-Showalter match. Mr. Showalter did not play 
nearly so well as last year, and was defeated by seven 
games to three, with two draws. Mr. D. G. Baird has 
tied with Mr. Kohler for the championship of the Manhattan 
Chess Club. 

Herr Marco has won the latest Vienna Club tourney, 
Herr Schleohter being as low as fifth. The international 



tourney at Vienna begins this month. Considerable dis- 
satisfaction is expressed at the necessity for playing two 
rounds ; so unpopular, in fact, is this condition that the 
committee have been compelled to extend the time for 
entries, owing to the paucity of desirable competitors. It 
is stated that Herr Lasker will be among the abstainers on 
this account, and possibly, too, Mr. PUlsbury. Messrs. 
Blackburne, Burn, and Caro will represent Eugland. 

Mr. P. F. Blake, the eminent problem composer, has 
won the level tournament of the Manchester Chess Club. 
Mr. Lawrence has again won the City of London tourna- 
ment, although he started badly owing to ill-health. 
Messrs. L. Seraillier and W. Ward were leading for the 
greater part of the tournament. 

REVIEW. 
The Art of Chess. By James Mason. Second Edition. 
(Horace Cox.) This is an extension of the edition of 1895 
from three hundred and eleven to four hundred and twenty 
pages. The price is increased from five shillings to six 
shillings net. Apart from a very interesting and suggestive 
introduction, we find that the section on end games is in- 
creased by forty pages ; the part deaUng with middle-game 
combinations being practically the same as in the former 
edition. The section on openings, which Mr. Mason rightly 
and logically 'places last, is considerably enlarged, and again 
the introductory remarks are most useful. Mr. Mason has 
during the last few years attained the position of the leading 
English chess author. He is the first Englishman to treat 
the game as a science to the extent of adopting a scientific 
method and scientific language in expounding it. Mr. 
Mason's style is terse and epigrammatic — at times even 
Carlylean, but, above all things, Masonic. In other 
words, the book is eminently readable. 

KNOWLEDGE, PUBLISHED MONTHLY. 



Contents ol No. 150 (April). 

PAGE 

Economic Botany. By Jolin R. 

Jackson, A.L.S., etc 73 

The Stracture of Ireland. By 
GrenviUe A. J. Cole, u.b.i.a., 

F.o.s. (nimlratei) 74 

The Sea-Otter and its Extermina- 
tion. By K. Lydekker, b.a., 

r.R.s. (Illustrated) 78 

British Ornithological Notes 80 

Letters 81 

British Bees. — II. By Fred. 
Enock, F.L.s.,F.E.s.,€tc. (Illus- 
trated) 82 

lu the Moon's Northern Regions. 

By Arthur Mee, F.E.A.a &4 

Notices of Books 85 

Stars having Large Proper Motion. 

By E. C. Pickering 89 

The Level of Snnspots. By the 

Eev. Arthur East. (Uluslrafud) 89 
The Evolntionot the Venom-Fang. 

By Lionel Jerris. (lUustraUi) 91 

Notes on Comets and Meteors. 
By W. F. Denning, f.r.a.s 94 

The Face of the Sky for April. 

By Herbert Sadler, f.b.a.s 95 

Chess Column. By C. D. Locock 95 

Plate.— The Lunar Alps and their 
Neighbourhood. 



Contents of No. 151 (May). 

PAas 

British Bees. — III. By Fred. 
Enock, F.L.s.jF.E.s., etc. (niu»- 
trated) 97 

A Valley on Sao Nicolau, Cape 
Verde Islands. By Boyd Alex- 
ander, M.u.o.r. {llXusUated) ... 100 

Deserts and their Inhabitants. 
By K. Lydekker, B.A.,F.R,s. ... 101 

The Karkinokosm, or World of 
Crustacea.— III. By the Bev. 
Thomas E. B. Stebbing, m.a., 
F.R.9., F.L.S. (Illustrated) 104 

Nebulae and Eegion round y Cas- 
siopeise. By Isaac Eoberts, 

» SC, F.R.S. 105 

The Recent Eclipse. By E. 
Walter Maunder, f.b.a.s. 

(niustrafed) 107 

Notices of Books 109 

British Ornithological Notes 112 

Science Notes 112 

Letters 112 

Nature's Finer Forces.— Some 
Notes on Old Work and New 
Developments. By H. Snowden 

Ward, F.E.p.s 114 

Botanical Studies. — III. Junger- 
mannia. By A. Vanghan Jen- 
nings.F.L.s., F.o.s. (Iliustriited) 115 
Notes on Comets and Meteors. 

By W. F. Denning, f.b.a.s.... U8 
The Face of the Skv for May. 

By Herbert Sidler, f.r.a.s 119 

Chess Column. By CD. Locock 119 
Plate. — Nebalse near y Cassiopeifie. 



The yearly bound volumes of Knowledge, cloth gilt, 8s. tid., post free. 
Binding Cases, Is. 6d. each ; post free, Is. 9d. 

Subscribers' numbers bound (including case and Index), 2s. 6d. each volume. 
Index of Articles and Illustrations for 1891, 1892, 1894, 1395, 1886, and 1897 
can be supplied for 3d. each. 

" Knowledge " Annual Sabscription, throaghont the world, 
8s., post free. 

Conunnnications for the Editors and Books for Beview should be addressed 
Editors, " Kkowledgk," 326, High Holborn, London, W.C. 



July 1, 1898.] 



KNOWLEDGE. 



145 



>r^llHISTRATED MAGAZINE << 

Founded in i88i by RICHARD A. PROCTOR. 



LONDON: JULY 1, 1898. 



CONTENTS. 



The Karkinokosm, on World of Crustacea. — IV. By 
the Kev. TnoM.\s R. E. Stebbing, M.A., f.b.s , p.r..3. 
(Illustrated) 

A Classic Legacy ot Agriculture.— II. By John Mills. 
(Illustraled) 

"The Mimic Fires of Ocean." By G. Clabke XniALL, 

B.SC 

The Petroleum Industry.— II. By Gteoege T. Hollowat, 

ASSOC. K.o.s. (lOND.), F.i.c. (Illustrated) 

On the Eclipse Theory of Variable Stars. By Lieut.- 

Colon>-1 H. K. JiAEKWiCK. F.R.A.s. [Til Ksl rated) 

The Recent Eclipse.— The Lick Photographs of the 

Corona. By E. Walteb llArNDKB, f.e.as. (Plate)... 
Notices of Books 

Short Notices 

Books Received 

Obituary 

Letters :—W. H. S. MoscK ; J. E. aoBE 

Science Notes. (Illustrated) 

Self-Irrigation in Plants. By tlu> Rev. Alex. S. Wilsox, 

M.A., B.SC. {Illustrated) ... ... ..7 

British Ornithological Notes. Conducted by Habbt F. 

WiTHEEBT, r.Z.S., M.B.O.U 

Botanical Studies.— IV. Mnium. By A. YArGHfN 

Jesnixgs, F.L.S., F.G.s. (Illustrated) 
Notes on Comets and Meteors. By W. F. DENNnra, 

F.E.A.S 

The Face of the Sky for July. By A. Fowibb, f.b.a.s. ... 
Chess Column. By C. D. Locook, b.a 



145 

148 

loO 

151 

1.5.3 

135 
156 
157 

157 
158 
159 
159 

1150 

HJ2 

163 

166 
167 
167 



THE KARKINOKOSM, OR WORLD OF 
CRUSTACEA.-IV. 

By the Rev. Thomas, R. R. Stebbing, m.a., f.k.s., f.l.s. 

SEEING that the mammalian tail is allowed to con- 
tract or expand the number of its joints at discre- 
tion, it looks like a kind of obstinacy in natural 
arithmetic that has assigned seven vertebrse alike 
to the neck of the hippopotamus and the neck of 
the giraii'e. Attention has already been drawn to a similar 
case of numerical persistence in the Karkinokosm. The 
whole of the great and diversified sub-class of the Malacos- 
traca is bound together by the circumstance that the body 
segments never exceed twenty-one, and only fall short of 
that number when motives of personal convenience have 
induced a broad Cancrid, for example, to consolidate, or a 
threadlike Caprellid to relinquish, some of its somites. 
But the other great sub-class, the Entomostraca, prefers 
always to have a number of body segments greater or 
smaller than twenty-one. Between these two sub-classes 
some authors give an independent position to the little 
group of the Nebaliidse. 

Xebaliu hipes has a wide distribution in the northern 
hemisphere. You may find it at Spitzbergen and in the 



Mediterranean. You may find it also under stones on the 
south coast of Devon, always exquisitely neat, however 
untidy the surroundings may be. In this half-inch of 
animal organism there can be counted twenty pairs of 
appendages, exactly the full number allotted to the Mala- 
costraca, and implying a corresponding number of segments ; 
but at the tail end of this creature there are two extra 
segments and a pair of caudal branches. Moreover, in 
Xihalia the eight pairs of limbs which follow the maxilljc 
are all of a peculiar pattern. The leglike character of the 
main stem is overshadowed by the great leaflike expan- 
sion of the subsidiary branches, which have a respiratory 
function : they act as branchiae or gills. 

Though in Crustacea the gills are commonly enough 
connected with the feet, yet the order Branchiopoda has a 
special claim to take its name from this connection, because 
the branchial character of the feet, instead of being, as 
elsewhere, subordinate or modestly withdrawn from view, 
is here monstrously developed and prodigiously obtrusive. 

The order Branchiopoda is so extensive a division of the 
Entomostraca that it has to be again divided into four sub- 
orders, with names that may not sound to all ears alluringly 
mellifluous, but which are moderately handy and in their 
measure significant. The four names are Phyllocarida, 
Phyllupoda, Cladiicera, Branchiura. These names, being 
interpreted, are Leafy Shrimps, Leafy Legs, Branching 
Antennae, Gill Tails. Unfortunately the interpretation 
needs an interpreter, just as it is not enough for us to 
know that Hiawatha is the Teacher, and that his wife's 
name, Minehaha, means Laughing Water, or that Mudje- 
keewis is the West Wind, and that the Kingdom of 
Ponemak is the Land of the Hereafter. The poet needs 
five or six thousand lines to unfold the story of these 
names, and to bring the hero to the haven where he 
would be. 

The Phyllocarida are represented by the border tribe of 
the Nebaliidffi. Till the voyage of the Cludlemjer that 
little group contained but one genus. Now it has three, 
and it is a curious thing that in one of the two new forms 
the breathing legs are exceedingly long, while in the other 
they are exceedingly short, the old northern genus standing 
intermediate between them. 

At no great distance from the Phyllocarida may be set 
the Phyllopoda, with a name that differs little from theirs 
either in sound or sense. It refers to the same feature in 
their construction — the leaflike limbs. The Phyllopods 
have been dinded into three groups, closely connected, 
but, in one respect, singularly unlike. One set have a 
dorsal shield, leaving a long caudal part exposed ; another 
set are enclosed in a pair of valves in such a way that they 
might well be mistaken for little molluscs ; whUe the third 
set are really quite too informal, almost indecorously 
negligent of the conventionalities observed by the respect- 
able class of Crustacea. These have no dorsal shield, no 
' covering valves, no encrusting carapace ; but each swims 
about unencumbered, a vagrant " neat and slim, without a 
rag to cover him." 

Of the last-mentioned group two forms were at one time well 
known in England, though of late years no one seems able 
to come across them. One of these, Artemia sa/ina, the brine 
shrimp, occurred at Lymington, in Hampshire, myriads of 
these graceful little creatures curvetting and gambolling 
about in the strong brine of the salterns. They are not 
marine animals. None of the known Phyllopods exist in 
the sea. Not too many tears need be shed over our lost 
Lymington specie^, for it is known to inhabit in countless 
numbers shallow brackish- water ponds along the shores of 
Europe, and a very similar form abounds in the Great 
Salt Lake at Utah, in the United States of America. Our 



146 



KNOWLEDGE 



[July 1, 1898. 



other missing species is Chiroceplial'u.i diaphanvs, the fairy 
shrimp. The name of the creature is deservedly pre- 
possessing and rightly suggestive of its real beauty. Of 
this no picture conveys any adequate idea, because the 
great antennae, or " hands on the head," to which the 
generic name refers, distract attention and look clumsy in 
a drawing ; while the pellucid limpidity of the whole 

organism, its 
iridescent 
colouring, and 
the graceful 
vivacity of its 
motions be- 
long to nature 
rather than 
art. One point 
in the history 
of this fairy is 
apt to excite a 
smile of in- 
credulity, for 
it is said to be 
found in places 
quite out of 
harmony with 
the birth of an 
Oberon or a 
Titania — " in 
stagnant 
water, very 
often in the 
ditches and 
deep cart-ruts 
on the edges 
of woods and 
plantations." 
These wood- 
land cart-ruts, 
as everyone 
knows, though 
soft and brim- 
ming with 
water at times, 
become at 
other times 
perfectly dry 
and of a stony 
hardness. It 
may seem, 
therefore, like 
one of Baron 
Munchausen's 
miracles to 
people these 
transient 
troughs with 
crustaceans an inch in length. They cannot fall from the 
sky. Spontaneous generation has never been accused of 
producing shrimps. The fact is that inland Entomostraca 
accommodate themselves, like the Rose of Jericho, to the 
exigencies of recurrent drought and varying seasons. 
Though they are inhabitants of water, their eggs can retain 
vitality unimpaired for long periods after complete desicca- 
tion of the mud in which they have been deposited. For 
observing the development and habits of numerous species 
belonging to the remotest lands, it is no longer necessary 
for the student to extend his survey by toilsome travel from 
China to Peru, lie can engage a correspondent to send 
him by post a small piece of Australia or Egypt, a sample of 




Nebalia /-i>e« (O, Fahi-icius). 



Siberia or Ceylon. It is a pleasing experience to find a hand- 
ful of earth, dug out of a pond at the other side of the globe, 
teeming with foreign species responsive to the gift of a 
cup of cold water poured upon the thirsty soil. In these 
experiments it is expedient in Great Britain to wake up a 
tropical brood, not amidst our frosts and fogs and chilling 
east winds, but when warm nights and summer sun, in 
which such broods delight, will favour their quick develop- 
ing, until it can be said that— 

' Cupid, empire sure, 
Fluttcr'd and laugh'd, and ofttimes through the throng 
Made a delighted way." 

These Phyllopods go through strange metamorphoses, 
for whereas in the full-grown condition they come to have 
from ten to more than sixty pairs of legs, they almost 
always begin life in what is called the iiaupliu.t stage, 
with no true legs whatever, having to be content with two 
pairs of antennn' and a pair of " mandibular legs " that are 
not permanent. With this limited apparatus they manage 
to jerk about in their watery world with tolerable activity. 
Instead of a pair of compound eyes the young ones are 
provided only with a central ocellus, the nauplian eye — 
sufficient, no doubt, for their childish wants. Like crusta- 
ceans in general, Phyllopods pass from stage to stage of 




Dorsal View. V.-utral View. 

Lepidiiru\ arrdens (I'liUas).* 

development and of growth by shedding the skin. Their 
exuvise are easy to collect and examine when the pond 
containing them is a bowl on a table. \\'ith the eye- 

* "FaunaNor7egiffi,"Bd. I., Tab. XI. By G. O. Sars. 1896. 



JrLY 1, 1898.] 



KNOWLEDGE. 



117 



cases and antennas, the oral parts and the respiratory 
limbs, the bright spines and feathered hairs — all the 
delicate structure, glassily transparent, is exposed to view, 
like the wreathed pearls, the unclasped jewels, and the 
rich attire which Madeline had put off on that famed Eve 
of St. Agnes, when, enamoured and entranced, " Porphyro 
gazed upon her empty dress. " 

The I'hyllopod's story, however, is not exclusively 
romantic. The cultivation of many species in a small bowl 
is convenient for the observer, but it also gives the stronger 
forms great and not always unwelcome facility for preying 
on the weaker. A couple of the Kstherin ijihoni, figured 
in the first chapter, caused me much surprise one summer 
for two reasons. First, the pair attained an unwonted 
size, which implied that the conditions were healthy ; but, 
secondly, contrary to custom, all other animals, even those 
of the same species, though grown under the 
same conditions, speedily disappeared. At .,-, 

last the pair that had waxen fat were put 
to death, just to see what would happen, and 
straightway a brood of youug Estheria grew 
up and prospered. It seems scarcely uncharit- 
able to infer that the long-dominant pair had 
thriven on cannibalism. In the kindred genus, 
Limnndia, there is another strange circum- 
stance which interferes with romance. Of 
this genus only two species are as yet known 
— one European and one American — and in 
neither of them has any specimen of the male 
sex been observed. The propagation, according 
to Prof. G. 0. Sars (an unsurpassed authority), 
is exclusively parthenogenetic. " Males," he 
gays, " in spite of the most careful investiga- 
tion, have not yet been found, and probably 
do not exist." It is not a little wonderful that 
these Amazons should occur in a group which 
commonly has both sexes abundantly repre- 
sented. But perhaps the effacement of the 
inferior sex will prove even here not to be 
quite so absolute as for the moment it seems, 
although the Russian and Hungarian natu- 
ralists, Krynicki and Chyzer, who claim to have 
observed the males, may have been deceived 
as to the species they examined. 

The division of the Phyllopods with a cara- 
pace or dorsal shield contains the largest of aU 
the species, Apus aitstrnlitnsis Spencer and Hall, 
nearly three inches long, and Ltjii'luriis inacni- 
nis, exceeding an inch and a half in length. Fig 
It is in this division also that the legs reach the Fig 
surprising number of a hundred and twenty- 
six. This being the case, it will appear an odd thing that 
the primary genus, which is scarcely or not at all to be 
distinguished from Lejiidunis, should have been called Apu^ 
— that is to say, " the legless." The explanation is this. 
The ingenious Dr. Johannes Leonhard Frisch, who in 1732 
published the first description and figures of what he called 
" the fin-footed lake worm with the shield," did not over- 
look the little packet of almost innumerable leaflets under 
the trunk, but decided that they were more like fins than 
feet. He therefore obligingly left it open for those who 
thought them legs to call this " insect " or " water worm " 
a, polypus — that is, " many legs," while for him it was pre- 
ferentially an aptia, or " no legs." 

In the Apodidte it may be noted that the males are very 
rare ; and abundant as the females are in some parts of 
the world, the student in England may not always find 
specimens at his command. He can always solace himself 
by having recourse to the Cladocera. These are distin- 



guished by the conspicuously branched second pair of 
antenna', which are their swimming organs. They content 
themselves with a comparatively parsimonious number of 
legs— from four to six pairs— and have the whole body 
except the head encased in valves, which, for the benefit of 
the naturalist, are often conveniently transparent. In all 
countries may be found some puddle, pool, or pond, some 
swamp, or tarn, or lake ; and therefore in all countries the 
zoologist may recognize a link with home by finding 
Daphnia puh'x or one of its near relations. In numbers 
numberless may members of this prolific tribe be obtained 
by dipping a net into almost any horsepond. Their 
movements can be studied by transferring a few to a 
tumbler of water ; their organization by isolating one in a 
watch-glass under the microscope. No Runtgen rays are 
needed. The living works of the machine are plain for 




on left, Daphnia carinata, var. intermedia Sare, female with epMppium. 
on right, typical form of Daphnia carinata King, ovigerous female.* 

all folk to see. It is worth taking a little trouble to 
observe the winking of that ever-trembling eye, the motions 
and adornment of the branchial feet, the little pulsating 
heart, the strokes of the spiniferous tail, the curious 
sinuosity of the intestine. One may chance to see the 
eggs pouring from the ovary and taking shape in the 
maternal pouch. Often within that pouch may be seen 
numerous eggs or young ones forward in development. 
Daphnia islike^piw, the prevalent method of reproduction 
being, as Dr. G. S. Brady expounds the matter, '• not 
sexual at all, but parthenogenetic, the female producing 
and detaching in rapid succession broods of young, which 
are the restilt of the development, not of fertilized eggs, 
but of mere buds or " pseudova." The fertilized eggs, 
the winter eggs, the eggs which keep and pass the winter 

* ■' On Fresh-water Entomostraca from the Neighbourhood of 
Sydney, partly raised from Dried Mud." By G. O. Sars. PI. I. 1896. 



148 



KNOWLEDGE. 



[July 1, 1898. 



independent of maternal care, are laid in the so-called 
" ephippium " — a case developed in the mother for this 
special purpose, and subsequently detached. An old 
writer has been scoffed at for speaking of Daphniu judex 
as a " wonderful insect." It is not in modern classifica- 
tion an insect. Of forms now known which belong to the 
same social set it is by no means the most eccentric. It 
is not rare, but, on the contrary, multitudinously common. 
None the less, it is to my mind easy to sympathize with 
Bradley when he caUed it wonderful. 



A CLASSIC LEGACY OF AGRICULTURE.-U. 

By .John Mills. 

THERE is no more beneiicial creation of wealth than 
that which arises from the complete development 
of the resources of the soil and the correct 
manipulation of its products. Better education 
in agriculture would contribute largely to an 
intelligent appreciation of the problems which arise in 
farming as a business, and increase the efficiency of the 
mental machinery destined to direct operations in the field. 
Farmers of the future, whose minds are thus counterpoised 
and adjusted so as to retain their equilibrium under all 
conditions — favourable and unfavourable — will play an 
important part in the struggle for supremacy between 
civilized countries ; and, so equipped, complete confidence 
may be placed in the ability of the tillers of the soil in 
our own country to maintain a secure place in the markets 
with rivals, distant and near, who make it their chief 
occupation to supply cur population with food. In the 
attainment of such knowledge a great multitude of facts 
present themselves for consideration, each of which requires 
due thought to discern its bearing on the whole and to 
assign it a place in agriculture so as to render the science 
of maximum usefulness. Thus, the quantity and quality 
of the crops, the character of the soil and of the climate, 
differences in the habits of plants, general economy of the 
farm, and so on, give rise to a number of questions which 
form a sort of algebraic equation involving many unknown 
quantities, and to solve which requires not only a vast 
amount of exact observation, but also profound skill in 
the marshalling of facts and manipulation of data. The 
experiments at Eothamsted, conducted by Sir John Lawes 
and Sir Henry Gilbert, are of this complicated description, 
some of the results being merely tentative. 

The object to be attained in the cultivation of root crops 
is to encourage, by artificial means, a quite abnormal 
development of a particular part of the plant. If, for 
example, the turnip plant were grown for its natural seed- 
product oil, a heavier soil would be more suitable than 
when the object is to develop the swollen root. When 
grown in ordinary soil without manure, either for a few 
years in succession or even in rotation, root crops scon 
revert to the uncultivated condition ; they depend for 
luxuriant growth on an abundance of nitrogenous as well as 
mineral constituents within the soil, and they are therefore 
generally highly manured. In the accompanying table, 
the results obtained with Norfolk white turnips are shown, 
NoBFOLK White Tuenips, without Manube, axd with 
Faemtaed Manuek. 





Roots per Acre. 


Leaves per Acre. 


Year. 


Without j With Farm- 
Manure, yard Manure. 


Without 
Manure. 


With Farm- 
yard Manure. 


1843 
1844 
1845 


Tons. cwts. 1 Tons. cwts. ' 
4 4 ' 9 10 
2 4 10 15 

14 1 17 1 j 


Tons. cwts. 

1 not weighed 

14 


Tons. cwts. 
not weighed 
• 7 8 



and it will be noted that when grown without manure the 
crop dwindles down almost to zero, whilst with farmyard 
manure there is a marked increase year by year. The 
form of the unmanured root resembles that of a carrot 
more than a turnip, and its composition is totally different 
from the cultivated root. There is, indeed, much more 
nitrogen taken up by the latter, but the percentage of that 
element — apparently lower than in the unmanured plant — 
is masked by the accumulation of a large amount of other 
matters which render the plant an important food crop. 
The average proportion of leaf to root under different 
conditions as to manuring clearly indicates the suscepti- 
bility of these plants to artificial influences : to one thousand 
of root with mineral manure alone, the yield of leaf 
being three hundred and twenty-nine ; with mineral and 
ammonium salts, four hundred and thirty-four ; and with 
mineral and ammonium salts and rape cake, six hundred. 

Potatoes have been grown on the estate for twenty-two 
years in succession, different sorts being selected on the 
supposition that in growing the crop year after year change 
was desirable, especially with a view to the avoidance or 
lessening of disease. It is now an established fact that 
season has much to do with the development of the potato 
disease, and these experiments show that there was on the 
average much more disease in the wetter seasons. When 
the unsuitable weather comes, those tubers suffer the most 
which have the richest juice — that is, the least fixity of 
composition. The first material change in the develop- 
ment of the disease is, apparently, the destruction of 
starch and the formation of sugar ; there is also a con- 
siderable loss of organic and chiefly ?io?! -nitrogenous sub- 
stance, due in part to the decomposition of the produced 
sugar, but probably in some measure to the evolution of 
carbonic acid, as a coincident of the growth of the fungus 
at the expense of ready-formed organic substance, this being 
a characteristic of the growth of such non-chlorophyllous 
plants. Regarding the cultivation of the plant under varying 
conditions, it is somewhat interesting to observe that the 
produce of starch per acre was about one thousand one 
hundred pounds without manure, nearly two thousand 
pounds with purely mineral manure, and with nitrogenous 
and mineral manures together about three thousand four 
hundred pounds. In other words, the increased produce 
of starch by the use of the mineral and nitrogenous 
manures together was more than one ton per acre. That 
is to say, there was a great increase in the production of the 
«o?}-nitrogenous constituent, starch, by the use of nitrogen 
in manure — a striking result, indeed, and one more hint 
Ihat nature will have her own way, paradoxical though it 
may seem to us. In truth, it is for the production of the 
non-nitrogenous substances — starch, sugar, and cellulose — 
that our direct nitrogenous manures are chiefly used 1 

The fixation of free nitrogen directly from the atmo- 
sphere is a subject which has engaged the attention of 
many inquirers, notably Sir John Lawes and Sir Henry 
Gilbert at Eothamsted ; and a theme of much controversy 
among scientific men for many years past has been — 
" How is the fixation of nitrogen to be explained?" 
Diversity of opinion still obtains on this question, and, 
unfortunately, there is yet much to learn before a satis- 
factory answer can be given ; but though the explanation 
is wanting there can be no doubt that the fact of the 
fixation of free nitrogen in the growth of leguminosffi — 
clover, vetches, peas, beans, sainfoin, lucerne, and so on — 
under the influence of suitable microbe infection of the 
soil, and of the resulting nodule formation on the roots, 
may be considered as fully established. What, then, is 
the basis of this conclusion ? Recent experiments at 
Eothamsted show that, by adding to a sterilized sandy 



July 1, 1898.] 



KNOWLEDGE. 



149 



soil growing legaminous plants a small quantity of the 
watery extract of a soil containing the appropriate organ- 
isms, a marked development of the ao-called leguminous 
nodules on the roots is induced ; and that there is, coin- 
cidently, increased growth and gain of nitrogen. For 
example, in growing peas, there was limited growth in pot 1 
(see figure) with sand without soil extract, and also an 
entire absence of nodule formation on the roots. The 
increased growth in pots 2 and 3, with soil extract, was 
coincident with a very great development of nodules. 
In pot 4, with garden soil, itself supplying abundance 
of combined nitrogen and doubtless micro-organisms as 
well, there was also a considerable development of nodules, 
bat distinctly less than in either pot 2 or pot 3 with 
sand and soil extraci only. Further, without soil extract 
and without nodules there was no gain of nitrogen, but with 
soil extract and with nodule formation there was much 
gain of nitrogen. Experimental results, iu fact, clearly 
prove that there is immense gain of nitrogen under some 




Peas grown in Experiments on the Fixation of Free Nitrogen. 

conditions. It has also been conclusively shown that due 
infection of the soil and of the plant is an essential to 
success. The available evidence at the same time points 
to the conclusion that the soU may be duly infected for 
the growth of some descriptions of plants, but not for some 
other descriptions. Moreover, land which is, so to speak, 
quite exhausted so far as the growth of one leguminous 
crop is concerned, may still grow very luxuriant crops of 
another description of the same order, but of different 
habits of growth, and especially of unlike character and 
range of roots. 

Not only the facts ascertained iu the Eothamsted ex- 
periments and in other investigations, but also the history 
of agriculture throughout the world, so far as it is known, 
clearly show that a fertile soil is one which has accumulated 



within it the residue of long periods of previous vegetation, 
and that it bscomss infertile as this residue is removed. 
That this exhaustion proceeds slowly miy be gathered 
from the fact that wheat ha3 baen grown at Rotham3ted 
for more than fifty years in succession oa the sama land, 
and, setting aside fluctuations due to season, the produce 
has only bean reduced by an average of about one-sixth 
bushel per acre per annum, due to exhaustion. Without 
any manure whatever, the average annual produce for 
over fifty years was thirteen and a half bushels — a yield 
exceeding the average of the United States under ordinary 
cultivation, including their rich prairie lands, and about 
the average of the whole world. The accompanying table 



8 years, 
8 years, 
8 years, 
8 years, 
8 years, 
20 years, 
20 years, 
40 years, 
50 years, 



1852-59 
1860-67 
1868-75 
1876-83 
188-1-91 
1852-71 
1872-91 
1852-91 
1844-93 



U Tons 

Faruiyiird 

Mumire 

every 



Bushels. 
34t 
35^ 



39i 
351 
33| 
341 
33J 



Year. 



Bushels. 
16^ 
13J 
12i 

lot 

125 

14i 

IU 

13 

13i 



Mixed Ammo- 

Miueral | uium 
Manure Salts 

aloue. < aloue. 



BusKels. Bushels. 



19 

15i 

14 

121 

13i 

17 



32i 
3U 
28^ 
27i 
32^ 
31S 
29i 
30i 



shows that with farmyard manure the average annual 
produce over the fifty years of continuous growth was 
thirty-three and a half bushels — a result not far short of 
three times the average produce of the United States, and 
more than two and a half times the average of the whole 
of the wheat lands of the world. Artificially manured plots 
show that mineral manures alone gave very Uttle mcrease of 
produce ; that nitrogenous manures alone gave consider- 
ably more than mineral manures alone; but that mixtures 
of the two gave very much more than either separately. 
An inspection of the following table of results, as indicating 
the amounts of produce in the best and in the worst 
seasons of the forty years, will show how easy it is to form 
wrong conclusions as to the effects of different manures 
if experiments are conducted for one season only, or in 
only a few seasons, and if the characters of the seasons are 
not studied and due allowance made accordingly in drawing 

Wheat Year aft^-r Year on the Same Land. — Produce of the Best 
Season, 1863; of the Worst Season, 1879; and the Average of 
Forty Years, 1852-1891. 



Dressed Grain (per Acre). 



Descriptiou of Manures 
(Quantities per Acre). 



Unmannred 

Farmyard manure 

Mixed mineral manure alone 
Mixed mineral manure and 200 

pounds ammonium salts =^ 43 

pounds nitrogen 

Mixed mineral manure and 40O 

pounds ammonium salts = 86 

pounds nitrogen ... 
Mixed mineral manure and 550 

pounds nitrate soda ^ 86 pounds 

nitrogen 

Mixed mineral manure and 600 

poimds ammonium salts — 129 

pounds nitrogen 




55} 



5; 


U 


lot 


2.; 


16J 


-l 


22 


m 


20| 


3Si 



inferences from results obtained. Thus it will be seen 
that all the plats suffered severely in the bad season. 
Compare columns <( and b. In most cases (see columns 



150 



KNOWLEDGE 



[July 1, 1898. 



c and d) the difference between the produce of the best 
and the worst season approached, and in two cases actually 
exceeded, the average produce of the plats. 

More than two thousand years ago the Romans recognized 
the fact that leguminous crops enriched the soil for succeed- 
ing crops — in short , discovered what is termed the ' ' rotation 
of crops," a practice which is admitted to be the foundation 
of the improvements in our own agriculture. How, then, 
are the admittedly beneficial effects of alternate, as dis- 
tinguished from continuous, cropping to be explained ? 
Liebig's first definite theory on this subject assumed that 
the excreted matters of one description of crop were 
injurious to plants of the same description, but that they 
were not so, and might even be beneficial, to other kinds 
of plants. Later, he considered that, as the dift'erent plants 
had such diverse mineral requirements, the alternation of 
one kind with another relieved the soil from exhaustion, and 
discerned after many years that nitrogen probably played 
some important part in the matter. Boussiugault, in 
chemical statistics extending over ten years, came to the 
conclusion that the difference in the amounts of nitrogen 
taken up by various crops constituted a very important 
element in the explanation of the benefits of rotation. 
Prof. Daubeny, of Oxford, in testing De CandoUe's theory 
that the excretions of one kind of plant were injurious to 
plants of the same description, arrived at a negative 
conclusion, and recognized the validity of Boussingault's 
argument that the same kind of plant may continue to 
grow healthier on the same land for long periods of time ; 
and experience at Rothamsted also is conclusive against 
the theory of injurious or poisonous excretions. Upon the 
whole the results at Rothamsted show that the benefits 
of rotation are very various. The opportunities which 
alternate cropping affords for cleaning the land constitute 
a prominent element of advantage. The difference in the 
amounts available within the soil of the various mineral 
constituents is one element in the explanation ; but the 
facts relating to the amount and to the sources of the 
nitrogen of the different crops are of still greater signifi- 
cance. The varying requirements of the different crops, 
habits of growth, and capabilities of gathering and assimi- 
lating the necessary constituents have to be considered ; 
with a variety of crops the mechanical operations of the 
farm, involving horse and hand labour, are better distri- 
buted over the year, and are, therefore, more economically 
performed. 

.^ 

"THE MIMIC FIRES OF OCEAN." 

By G. Clabke Nuttall, b.sc. 

NATURE dazzles the eye of man with many wonder- 
ful phenomena, but perhaps never more so than 
when she turns the gloomy night waters of the 
sea into a sheet of silvery fire. At these times 
every movement of the wave, every cleavage of 
the water by oar or prow, reveals in its dark depths a 
hidden fire which scintillates and sparkles with weird 
and mysterious light. The spectacle is one of absolute 
fascination, for the Spirit of Enchantment rests upon the 
waters and reality becomes fairyland. 

The ancients, keenly alive to a sense of the supernatural, 
saw in this lunnnosity a manifestation of some unknown 
power, and wondered ; the ignorant read in it a portent of 
judgment and terror ; while in all ages the curious and the 
searchers after knowledge have speculated as to its cause. 
But just as nature has invested its appearance with a halo 
of mystery, so she has also wrapt in much obscurity its 
immediate cause ; and thus, though in the course of 
"cehturies varying suggestions have been put forward, 



nothing with any finality about it has been arrived at. 
It was asserted truly that certain fishes were luminons ; 
sharks have glowed and shone, shoals of herrings, pilchards, 
or mackerel have been moving masses of light, and the 
fish drawn out of the water have lain in great shining 
heaps, the glow of which vanished as they dried and died. 

Many writers have described the passages of ships 
through such shoals — the sheet of moving flames — the 
beautiful pale greenish elf-light that the fish exhibited ; 
while poets have apostrophized the " mimic fires of ocean " 
and the " lightnings of the wave," and scientists and 
naturalists have in turn tried to account for their power of 
luminosity. Some have attributed it to the presence of 
certain substances of a fatty nature excreted by the fish 
and adhering to the surface of their bodies ; others have 
declared that it is due to a subtle power of the fish itself 
— a form in which the energy of life shows itself under 
certain conditions, just as this energy may be exhibited 
in heat, or motion, or electricity; others, again, have 
ascribed it to direct absorption and transmission of the 
light of the sun, and so on. Many theories have been 
elaborated, but none convincingly. 

But now, it is asserted, the secret is laid bare. 

It is wonderful how many secrets the searching light of 
the nineteenth century is claiming to reveal. It is, perhaps, 
a matter for still more wonder whether in the far future our 
descendants will endorse all our solutions, or whether they 
will not smUe at some of them just as we, half contemp- 
tuously, discredit those of our ancestors. However that 
may be, we have, in this case, a solution offered to us that 
apparently approaches nearer the heart of truth than any 
yet put forward, in that it satisfies the various phases of 
the phenomenon and gives a unity and coherence to its 
manifestations. 

It is only lately that any very serious effort has been 
made to study this phenomenon, but the research has 
been abundantly rewarded, for it is now pretty certain 
that the luminosity is due to the presence in the water 
of various kinds of bacteria. 

Now, bacteria are the very smallest living organisms of 
which we have cognizance. Millions of them can lie on a 
penny ; therefore, to produce the gleaming appearance 
recognized by us as phosphorescence, they must be present 
in numbers too enormous even to contemplate with our 
finite minds. It would be immeasurably easier to reckon 
with the stars for multitude than with these phosphores- 
cent bacteria. They are colourless, rodlike bodies, only 
known to us in the land revealed by the highest powers of 
the microscope, and careful comparison shows minor 
differences among them. For instance, some of them are 
capable of independent motion — we can hardly call it swim- 
ming — others are non-motile, some are enclosed in a jelly- 
like covering, others are without this sheath. Their 
power of motion is probably due to excessively fine hairs 
at their extremities, which, moving to and fro in the water, 
act the part of oars. These cilia have not been found in 
all forms of bacteria which move, but their presence is 
inferred, since every advance in the study of motile forms 
increases the number of bacteria which are seen to possess 
them. 

These light-producing bacteria are known as photo- 
bacteria, and so far some half-dozen varieties have been 
distinguished and named. The names in such cases are 
usually either given from the locality of their appearance 
(thus, photo-bacterium Balticum, found in the Baltic), from 
their discoverer (for example, photo-bacterium Fischeri, 
after Prof. Fischer), or from some striking attribute (to 
wit, photo -bacterium phosphorescens, the commonest light- 
giving species). 



JrLY 1, 1898.] 



KNOWLEDGE. 



151 



That they lie at the bottom of the matter — that phos- 
phorescence is due to their presence — has been and can be 
proved in several rather pretty ways. It is not sulScient, 
of course, that we should always detect them in any 
examination of luminous sea- water; to prove that they are 
the cause of light we must be able to procure luminosity 
by introducing them into water that did not previously 
show this quality, and this can be done thus ; — 

Place a few of these tiny organisms into sea-water or 
broth prepared from fish, and Iceep at a suitable tempera- 
ture ; they can then be cultivated without much ditliculty, 
and as they spread and develop phosphorescence appears, 
so that a removal of the vessel into another room shows 
unmistakably the glow of the familiar li,L;ht. It only 
appears, however, at the surface of the liquid, where the 
oxygen of the air has free access to the bacteria ; if, for 
experiment's sake, the supply of fresh air be cut off — that 
is, if no oxygen be allowed to come near them^then the 
little colony of bacteria loses its fascinating power and 
remains dull and shorn of its glory. But restore the air, 
and the microbes again recover their normal condition and 
luminosity seems a natural corollary. There is a tale 
told that a lady, whose husband made bacteria his study, 
took a leaf out of his book, and cultivated these bacteria on 
gelatine in such a way that as they developed they shone 
out the message, " Hommage a M. Pasteur." The shining 
letters were then photographed and the picture sent to 
the great bacteriologist, thus conveying in graceful form 
the warm appreciation in which he was held by those 
following in his steps. 

The explanation, too, of the luminous shoals of fish is 
now made plain, and we can apparently get " fiery 
herrings " at will. No longer are we to believe that the 
herrings themselves, by the exercise of some marvellous 
power, or by the excretion of an extraordinary substance, 
give rise to the striking luminosity, but rather that their 
brightness is due to myriads of these infinitesimal bodies, 
which cling to their surfaces and invest them in a coat of 
shining light. Thus, if some herrings, newly caught, and 
with the sea-water still fresh on them, be placed on one 
plate and covered down with another, and then put into a 
suitable temperature and left for a day and a night, glints 
of light can, at the end of the time, be detected at various 
points on their bodies when they are examined in a dark 
room. If they are yet again put away for another twenty- 
four hours, the points of light spread until the whole ol' 
the fish are enveloped in a beautiful bluish glow. The 
light is then at its best, and gradually fades away as the 
fish putrefies and the sea-water dries up. If a little of 
the light-giving matter be scraped ofl' the skins of the 
herrings and examined under the microscope, it shows 
itself to be nothing but colonies or collections of bacteria, 
all living at a great pace, dividing, multiplying, ami 
developing at a tremendous rate. Each member of a 
colony is normally roundish in shape, but in this stage of 
reproduction it is continually elongating into a long ellipse, 
a constriction appears at the middle, and it divides into 
two. Eacli of these two in their turn elongate, become 
constricted, and divide. And so it goes on, the process 
being often so rapid that short chains are formed, the 
various portions being unable to break away in time. The 
particular bacterium which affects herrings and cod is 
remarkable for its great luminosity ; in fact, it exceeds all 
other species in this quality. 

It is a curious fact that the addition of a little sugar to 
the liquid or the gelatine on which these phosphorescent 
bacteria are being cultivated increases very much their 
power of producing light ; the sugar must, however, be 
used with great moderation, as too much of it has a con- 



trary effect and checks the luminosity altogether. The 
reason for this is that nearly all this class of bacteria 
require carbon as nourishment if they are to develop to 
their highest powers. Like much of the food we eat, it is 
not essential to them ; they can manage very well without 
it, but they are all the better for having it. Now sugar is 
very largely composed of carbon ; hence the good results 
which follow its presence. Glycerine, which is of similar 
composition, will do almost as well ; from both bacteria 
can easily withdraw carbon. Two photo-bacteria have, 
however, been observed which are somewhat differently 
constituted ; one is found round the West Indies and the 
other in the North Sea, and neither apparently requires 
sugar or glycerine in any form — in fact, either of these 
substances, even in the smallest quantity, appears to be 
directly injurious. But why this should be so it is not 
easy to define. 

A Dutchman named Beyerinck lias lately made a special 
study of these photo-bacteria, and has experimented with 
them in a great number of ways to determine, if possible, 
why they should thus become illuminated, and if the light 
plays any notable part in their life history ; but his results 
are, seemingly, all more or less of a negative nature. 
He cannot find that it has any very important function. 
The breathing of these tiny organisms is not, apparently, 
in anyway bound up with it ; their nutrition, growth, and 
development go on quite well even if they are placed 
under such conditions that their luminosity is arrested ; in 
no way, indeed, is it a vital process. It only seems to 
depend on the food which the bacteria feed upon and the 
presence of oxygen. Given suitable food and plenty of 
fresh air, and they exhibit their characteristic light ; deprive 
them of one or the other and they no longer shine. 

This knowledge helps us to understand, then, the 
phenomenon of phosphorescence. It is visible only at 
night because in the full glare of day the greater light 
overpowers the lesser ; it is visible at certain times and 
seasons because the conditions are such as to evoke it. 
And what is favourable for the Lighting up of a single 
bacterium is favourable for all ; hence the myriad multitudes 
of infinitesimal units, each set glowing with its tiny light, 
is sutficient in the sum total to put a whole ocean aflame. 

It would, of course, be presumptuous, and doubtless 
erroneous, to say that all the phosphorescence of the sea 
is due solely to photo-bacteria ; it can only be asserted in 
the present state of our knowledge that they are certainly 
responsible for a great share of it. But this wonder of 
nature must now be regarded as yet another instance of 
the mighty results accomplished through the agency of 
the smallest of living things. 



THE PETROLEUM INDUSTRY.-II. 

By George T. Holloway, assoc. r.c.s. (lond.), f.i.c. 

IN the earlier days of the petroleum industry the crude 
oil was carried from the wells to the refineries in 
barrels containing forty-two American gallons, at 
such heavy expense as to enormously increase the 
cost to the consumer. By land the barrels were 
conveyed on rough waggons over the almost roadless tracts 
where the oilfields were mainly located, while, where 
river transport was possible, barges were used as the 
vehicles of transportation. In 1862, however, a branch 
railway was carried into the oil regions of Pennsylvania, 
and in 1866 railway tank waggons were introduced. At 
first constructed of wood, and having a capacity of about 
two thousand gallons, these waggons were soon replaced 
by the boiler- iron tanks with which we are now familiar. 



152 



KNOWLEDGE 



[July 1, 1898. 



These tanks, of which over ten thousand are in use in the 
States, usually have a capacity of eight thousand American 
gallons. 

The introduction of pipe-lines — which are now laid from 
all the important oilfields to the central refineries — con- 
stitutes the greatest factor among the many innovations 
which have, as a whole, led to the present cheap produc- 
tion of petroleum in the States. Each well-owner, as his 
oil is passed into the pipes, receives a certificate stating 
that he is entitled to so much oil, and these certificates 
are negotiable like bank-notes among those interested in 
the trade. Of course, all the oil passes into the common 
stock, so that no producer can obtain his own oil from the 
refinery ; and for this reason any special oil, such as the 
heavy and valuable oils of Franklin and Smith's Ferry, is 
still conveyed in barrels. 

The use of pipe-lines was proposed in 18G0, but the first 
successful line was laid in 18G5. Notwithstanding the 
opposition of the teamsters, who had formerly enjoyei 
the monopoly of the transport of petroleum, the laying of 
these lines proceeded rapidly from the first, and it is said 
that between twenty-five thousand and thirty thousand 
miles of pipe-lines now exist in the States. 




Uil Keiinerv nx I'luladelpina. 

The main pipes are U3ually from four to six inches in 
diameter, the small feeders which pass from them to the 
wells being about two ioches. As the pipes are liable to 
become choked by dirt or solid hydrocarbons, a small brush, 
known as a "go devil," is occasionally passed through to 
clear them. This brush, which travels along with the 
oil as the latter is pumped through the pipes, is provided 
with ball-and-socket joints, to facilitate its progress round 
the bends ; and it is also fitted with vanes, which ensure 
its rotation as it advances. 

The pumps now invariably ussd for these pipe-lines are 
of the Worthington type, and work at a pressure which 
sometimes rises as high as one thousand five hundred 
pounds per square inch. The seven hundred and sixty 
mile length of six-inch pipe extending along the New York 
line is supplied by pumps of from six hundred to eight 
hundred horse-power, and conveys about thirty thousand 
gallons daily. There are eleven pumping stations, each 



containing two pumps. In one case a pair of these pumps 
forces the oil through a distance of one hundred and ten 
miles, but as a rule each pair serves about half that length. 
Kerosene — the product of the distillation of crude 
petroleum used as lamp oil— is mainly conveyed in tank 
waggons or railway cars, tank barges, and tank steamers ; 
but a small proportion is still sold in barrels, and, especially 
in the Eastern markets, considerable quantities are disposed 
of in tin "cases," each fitted with a screw cap and wire 
handle, and holding about five American gallons. S3 
great is the sale of these cases that as much as forty 
thousand tons of tinplate is said to have been used in 
their manufacture in one year. 

For ocean transport the oil is now usually conveyed in 
tank steamers and sailing vessels, in which the whole hold 
is formed in compartments or tanks to contain the oil. 
In order to prevent injury to the vessels from the rolling 
about of the oil in bad weather, the tanks are kept 
absolutely fall, small auxiliary " expansion tanks ' being 
fitted to them to receive any overflow when the oil expands 
from rise of temperature, or to supply oil to the main 
tanks when the bulk decreases. Practically the whole of 
the ocean tratlie, both of kerosene, crude oil, and liquid 
fuel, is now controlled by "these 
vessels, although lubricating oil 
and petroleum spirit, and other 
of the lighter petroleum products, 
are still conveyed in barrels. The 
credit for the introduction of this 
method of transport is due to 
Mr. Ludwig Nobel, who, in 1878, 
had two small tank steamers 
constructed for use on the 
Caspian. They were built at 
Motala, in Sweden, in sections, 
for conveyance to the Caspian, 
where they are said to be still in 
use. 

In the earlier days the escape 
of gas and inflammable vapours 
from the oil led to many disastrous 
explosions, but the more efficient 
methods of ventilation now in 
vogue have minimized these dan- 
gers. The tanks are also now 
so arranged that they may be 
thoroughly cleansed by workmen 
and used for the conveyance of 
ordinary cargo on the return 
journey, and the most perishable 
goods are so transported. 
As the crude petroleum consists of a large number of 
constituents in admixture, from dissolved gas and highly 
volatile " petroleum spirits " to such solids as paratfin wax 
and vaseline, it is resolved by distillation into the various 
components used in commerce. For this purpose various 
types of still have been devised, the Russians largely using 
the " continuous " still, in which the crude oil is supplied 
as fast as the distillate passes off; while, in the States, 
large non-continuous stills, which are cooled down and 
the residuum removed after each distillation, are princi- 
pally in use. It is well known that, in distilling any such 
mixture as petroleum, some of the constituents are decom- 
posed into other bodies which are mainly more volatile 
than the substance producing them. In what is known as 
the " cracking process " this decomposition is accentuated 
by allowing a portion of the distillate to condense on the 
cooler upper part of the still, and run back upon the hotter 
liquid at the bottom. This action is not allowed to take 



July 1, 1898.] 



KNOWLEDGE. 



153 



place until the bulk of the lighter oila and "natural" 
kerosene have been distilled oS, as it is the hea\aer and 
less valuable constituents of the crude petroleum which it 
is desired to decompose in order that the maximum of 
kerosene may be obtained. The distillate is agitated with 
sulphuric acid followed by a treatment with caustic soda 
lye, and it is finally washed by agitation with water, from 
which it is drawn off after settlement. The exact action 
of the chemical treatment is not known, but it appears to 
consist mainly in the removal of the tarry matters, the 
aromatic hydrocarbons, and the sulphur compounds, all of 
which injure the quality as well as mar the appearance of 
the oil. 

The nature of the products obtained at different distil- 
leries varies according to the market for which they are 
intended. The oil allowed to be burnt in lamps in England, 
for instance, must not " flash" — that is, giveoff inflammable 
vapour in a closnl vessel — at a temperature below seventy- 
three degrees Fahren., while in some countries the standard 
is higher and in others lower. The principal products 
recognized in the trade are : — (1) The lightest, i.e., the 
most volatile constituents, known as petroleum spirit or 
naphtha, which is sometimes again divided up into rhigo- 
lene or cymogene, gasoUne, benzoline, benzine, etc. (2) 
Kerosene for burning in lamps. This, the most important 
of the products of petroleum, constitutes about seventy per 
cent, of the yield from the oil of the United States and 
about half as much from that of Kussia — a feature which 
has had much to do with the greater success of the 
Americans. (3) Oil somewhat heavier than kerosene, 
but still capable of burning in suitably constructed lamps. 
(41 Lubricating oil, which, on account of its feebler 
action on metals and its less tendency to clog machinery, 
as compared with the animal and vegetable oils formerly 
exclusively used, has now practically displaced the latter 
in the markets of the world. (5) Paraffin wax. (6) 
Vaseline. And (7) residuum, or waste, now used on an 
enormous scale as liquid fuel. Anthracene and other 
compounds from which dye-stuffs may be obtained have 
also been separated from the residuum, but the cost has 
so far proved prohibitive. 

The uses to which these various products have been put 
are very numerous. The earliest use of petroleum was, as 
already stated, for medicinal purposes — an application now 
mainly confined to vaseline and the softer paraffin waxes, 
which are largely used in preference to lard in the manu- 
facture of pomatum, etc. It is stated that vaseline, as well 
as much of the heavier petroleum oil, is used instead of 
butter in the manufacture of pastry on a large scale, but 
it is doubtful whether it possesses any value whatever as 
a food. 

The lightest of the petroleum spirits are used as local 
anassthetics, those of lesser volatUity being largely employed 
as solvents for waterproofing materials, varnishes, and as 
cleansing agents for the removal of grease spots ; also in 
the processes of " dry cleaning " for fabrics. It is, of 
course, as a lighting agent that petroleum is most used, 
the distillates known as kerosene being employed for that 
purpose, and the bulk of the candles now in use are 
prepared from the paraffin wax obtained from petroleum. 

The use of the heavier oils as lubricants has already 
been referred to, but it may be mentioned that the Russian 
oil holds the field as the best for this purpose, although 
its kerosene has not so good a name as that of America, 
mainly on account of the fact that the lamps (especially 
those in use in England) are especially designed for burning 
the American oil, which does not require so good an air 
supply for its combustion as does the Russian. 

For use as fuel, the Russian residuum is preferred to 



that of America on account of its greater fluidity. Under 
the name " astatki," or " masut," it is largely employed 
as fuel for stationary and locomotive engines, marine 
boilers, furnaces, etc., a jet of the sprayed residuum blown 
into the furnace by a blast of air or steam from a nozzle 
being the usual method of applying it. On account of the 
ease, with which this residuum may be stored, and, above 
all, of the almost total absence of smoke and dirt during 
its combustion and the little attention and stoking which 
is required, it is probable that in the near future its use on 
board ship will be greatly augmented. 

Finally, the use of petroleum distillates for enriching 
coal gas, either by merely passing the gas through the 
highly volatile gasoline, or by decomposing the heavier 
oil into illuminating gas, which is mixed with the coal gas, 
must be mentioned, together with the large and increasing 
use for " petroleum engines," in which vaporized or gasified 
petroleum spirit, or even kerosene, is exploded with air as 
in the gas engines, which some practical men consider will 
ultimately be replaced by those using petroleum. 



ON THE ECLIPSE THEORY OF VARIABLE 
STARS. 

By Lieut. -Colonel E. E. Maek^ick, k.r.a.s. 

THE theory that the variations in light of such stars 
as Algol are due to the presence of a dark or opaque 
companion star, which periodically passes between 
us and the bright star, is generally accepted as 
satisfactorily accounting for the observed changes 
in brightness. Vogel's almost classical determination of 
the elements of the system of Algol, uniting as it does 
the visual and spectroscopic observations, seems to have 
clinched the theory, and it has crystallized into a recog- 
nized fact in the text-book and lantern-slide worlds. It is 
with no idea of controverting this theory that this paper is 
written, but simply to examine some of the conditions 
which are attached to it, and study them from different 
points of view. 

For this purpose five different systems, each of two 
bodies revolving round their centre of gravity, are pro- 
pounded. The two bodies are denominated A and B 
respectively, and the following table gives the particulars 
of each : — 





Diameter of 


Remarks. 


System. 


A. B. 


I. 

II. 

III. 

IV. 
V. 


10 
10 
10 
10 
10 


9 

7 

!) 

9 


^ B, dark or opaque. 
) 

B, bright. 

B's albedo half that of A. 



With these data, the diminution in the light of A by the 
central transit of B was calculated for every one-tenth 
of diameter of A that B advances on its course, supposing 
B to move from right to left. Thus in Fig. 1 the area of 
the hme D E F G was calculated when the advancing limb 
of B had arrived respectively at 1, 2, 3, etc. Fig. 1 shows 
the occulting satellite (System I.) arrived at point 3. In 
this particiJar case the area of the lune is 14 31, the 
distance G E («) being :->. Taking the light of globe A to 
be represented by unity, the Hght cut off" is -182 ; the 
remaining light is SIS. Assume the " magnitude " of A 
when quite unobscured as 1-0 ; then the resulting mag- 



\64s 



KNOWLEDGE 



[July 1, 1898. 



nitude of the partly eclipsed globe is 1-22, based on the 
light ratio, 2-512. It is supposed that the distance of 
the bodies from us is so great that the telescope would 
only show them (even if both bright) as a single star. 

In this way the five systems have been treated, and 
a series of points plotted as in Fig. 2. The abscissa 
represents a unit of time, i.e., the period occupied Uy B 




in advancing one-tenth of the diameter of A. The motion 
is supposed uniform and transverse to the line of sight. 
The ordinates are star magnitudes divided into tenths, so 
that the length representing one-tenth of a magnitude 
equals that representing a unit of time. A curve is then 
drawn through the points, which we may call the theoretical 
light curve. 

It should be noted here that the shape of the light curve 
may be altered indefinitely by changing the ratio of time 
to " magnitude." But the light curves of different stars are 
strictly comparable provided the same ratio is maintained 
for all. For this reason the shape of the Algol curve, as 
given by Prof. Pickering in Fig. 3, differs widely from the 
theoretical curve in Fig. 2, simply because the above ratio 
adopted in the two cases is different. 

In System I. the diameter of the dark globe is one-tenth 
less than that of the bright one. This is pretty nearly 
the proportion as given by Vogel for the system of Algol. 
Hence a very considerable diminution or drop in light of 
A results, owing to so much of its face being obscured by 
the dark globe when central. 

In System II. the diameter of B is assumed seven as 
against ten of A. Hence the light curve is not so deep, 
and the central flat is longer ; lor, the occulting globe 
being smaller than in I., and supposing it to travel at 
same rate as before, it is, for a relatively longer time, 
wholly contained visually within the globe or projected 
superficies of A. While so contained the light of A is 
reduced to a minimum and theoretically does not change. 

In in. the small globe is half the diameter of the large 
one. Here the resulting light change is so small (only 
0-13 of a magnitude) that it would be practically unnoticed 
and undiscoverable by a method of visual observation such 
as Argelander's. Hence it would seem that any companion 
or planet smaller in diameter than -5 of the larger could 
never be discovered by present methods of visual observa- 
tion. If all the planets of our system could be seen 
projected on the sun, as seen from a star, the resulting 
diminution in his light would be absolutely unnoticeable. 

IV. Suppose now that globe B is bright — in fact, just 
the same brightness, surface for surface, as A. Then we 
have a binary system like many known ones, except that 
we are supposing the distance from us so great that it is 
beyond the power of any telescope to " split " the pair. In 



this case we regard the normal light as that of globe A 
plus globe B. Any portion of H projected on A makes no 
difference, seeing that any light obscured is replaced by 
a similar quantity. The quantity of light, therefore, 
outside the central globe — that is, the lune D G F H— 
must be calculated and result added to that of A. This 
has been done for the various positions when a 1, 2, 3, 
etc., and the fourth light curve results. 

In System V. the diameter of B is still regarded as nine, 
against ten of A, but the albedo, or light-reflecting power, 
only half that of A, surface for surface. In this case the 
total light when the globes are separated is that of A plus 
that of B. When in transit, as in Fig. 1, the total light 
is proportional to area of A, plus half area of B, minus 
area of lune D E F G. This has been worked out for 
different positions, and the fifth light curve obtained. 

All these five curves are similar in character, and the 
light curves of all possible varieties of binary systems can 
be thus represented. The amp