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^iM,

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

TORONTO

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I Law Hooks, A

OF CAN/::

TORG NTO,

Plainly Worded — Exactly Described,

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

'Let Knowledge grow from more to more "

— Tenw.son'.

Volume I.

JANUARY TO DECEMBER, 1904.

NEW SERIES

Volume 1.

london:

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

SEP 27 1968 y

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

KNOWLEDGE & SCIENTIFIC NEWS.

111.

INDEX.

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

PAGE

Achromatic Condenser ...

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

,, Experinientti at the Crystal Palace iii, 154

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

,, at the British Association ... 205

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

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

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

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

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

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

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

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

„ ,, Camel 25

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

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

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

„ Fasting 144

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

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

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

Anthropology at the British Association ... 204

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

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

" Argus," Attachable Mechanical Stage ... 47

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

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

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

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

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

Association of Academies, The International... 132

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

.Astronomical Notes

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

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

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

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

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

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

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

Balfour, Rt. Hon. A. J

,, Henry ...

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

Bird Life

,, Migration ...
Birds, Fossil
Birkbeck College

Blondlot " \ " Rays

Blood of Men and Apes ...

f Stars

127

'I. 154

197

204

77
140

4,S
261
244

241

18, 44

246

Borings on a Coral Island
Botanical Notes

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

,, ,, Presidential Addresses

Brook 's Comet

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

,, Rough-legged

Cachalot Whales

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

,, as an Industrial Metal

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

,, Nicaragua, an Eighteenth

Map of

Cancer, Latest Discoveries Concerning

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

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

,, at the British Association

Chess
Chimpanzee, .An Intelligent

,, and Gorillas

Chlorophane

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

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

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

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

,, .Analvsis of. Book on ...

,, of lobsters

,, in birds ...

,, of nestling birds
,, in beetles

I'A<iK

292

184
190

■97
123

92
96

126

151

106

37. 41. 67. 87, 96
Century

55
14

170

161

99
161

Comet,

I i;o4

Encke's

1903

S7. 79

201

K. 23

294
298

72
16

256

243
302
4, 250, 278
285
214

208

43
186

1G2
70
126
271
140
123
291
220

147. 243.

IV.

KNOWLEDGE & SCIENTIFIC NEWS.

Comet's Tails, Some peculiarities of ...

Conservation of Mars

Constellations, and Ancient Calendars
,, Antiquity of

,, Snake forms in ...

Coral Island, Borings on

Cosmic Physics at the British Association

Cosmogonies, Modern 30, So, 178, 211,

Crocodiles

Crystal, The Structure of

The Birth of

Cuckoo watching over its young

Cunningham, J. T., Discoveries in Cancer

Cygni, Nebulosities in ...

Dalny

Darwin, Francis ...

Davison, C, on Recent Explosions

Dead Sea, Saltness of ...

Denning, VV. F., on November Leonids

,, ,, Canals of Mars ...

,, ,, Observations on Mars

.. Jupiter

Dipleidoscope, A New Form of

" Discovery " Collections

Dolls of the Tombs

Double Stars, Measure of

Dugongs, Similarity to Elephants

Duration of Pregnancy in the Badger ...

Earth, The Vital

Earthquakes, Book on
Eclipse Problems

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

,, Decrease in Weight of ...

,, Weight of

Egyptian Fossils, New ...

Eight-Cell, Stereoscopic Projection of the

Electric Eye

,, Discharges in Air

,, Recording Apparatus, Patent

,, Sparks, Photographs of

,, Traction System

,, Wave Measurement

,, Ore Finding

,, Equilibrium of the Sun

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

,, and Dugongs, Similarity ...

Eliot, Sir John

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

,, Principles of, Teaching the

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

56,

14;

PAGE

281

118

227

3^
200
K. 6
161
109
182
222

14
10

17
205

94
10
21
67

41
148

185

15
16

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

49, 73
131, 244

157
186
269

36
4

15
200
126
291

II,

24.'

133
186
178
16
302

158

, 39

194

35, 57

, 79

lOI

125

162

125

161

...131,

244

••■ 3,

III

162

... K

• 13

■•■ 15,

162

124

246

305

175

...141,

231

... K. 3

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

,, Destruction of by Birds

Flying

Scales
,, Classification of

,, Habits of

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

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

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

,, New Egvptian ...

Birds "'

,, Mammals

,, Coal, Microphotograph of

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

Formation
Funafuti, Coral Island Borings
Fungi, Influence of

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

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

,, at the British Association

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

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

,, ,, Telegraphically Transmitting

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

,, and Fish
Gun, a Ball-Bearing Rifled

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

220

43
194

49
202
163
201
163
222

246

298

196

114
98

1.59
160
187

188

247

73
170

KNOWLEDGE & SCIENTIFIC NEWS.

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

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

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

246,
. 16,

241

'-5

103

206

290

109

162

247

293

Ibis, Glossv, in the Orkneys ...

126

Indigo

2, S3

Insects, Protective Resemblance of ...

• 51.

,, African ...

Pest

188

,, Terrifying Masks

208

Instincts, Primeval

Instruments, Geodetical

International Association of Academies

•.^2

Invar ... ...

176

Ivory, Supply of ...

..1S9,

2 -'3

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

Jones, Chapman, on Photography

117, 146, 174, 219, 286

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

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

Jovian Longitudes, Method of Determining ... 123

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

>» ,, >, ,, Camel ... 25

i> ,. ,, ,, Carnivora 61

M ,, Fasting Animals ... . . 144

>» ,, Later History of the Horse 171

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

Magnetism, Terrestrial ...
,, Sunspots and

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

,, of Central Asia

Mammoth Skull in Kent

Mantis

Marriott, W., on Meteorology

Mars, Canals on ... ... ... ••■37,

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

,, ,, Is there .Snow on

Moon ?
,, ,, .Solar Atmosphere

,, ,, .Snake Forms in C

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

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

,, Practical

Meteors, Leonids
Microscopical .Society, Roval

Table' ...'

Microscopy

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

Mites

Monkeys and Altitutle ...
,, Brain of

Mont Pelee, The Obelisk of

Moon, Photographic Atlas of the

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

... 96,

ji)i

2 1

42
246

268

2.[f)

13<J

87, 96,

26(1

242

...141,

231

the

IS"

on-

227

291

ep-

126

242

24. 50

. 7^>

167

K. II

, 21

75. 105

,'<>.^

225

24, 250,

306

)les

171

...104,

'34

<)6

3«

r,4

124

2fK1

N-rays, Phenomcn.-i

National Physical Laboratory ...

Natural History Specimens

Nature Printing ...

Nautilus and Flying Fish

Nebula;

,, Forms of

.\nd the Milky Way

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

18, 44, 92

102

23
238

l(>2

41
21 t

2^16

.•788

9
25'

1K4
98

VI.

KNOWLEDGE & SCIENTIFIC NEWS.

Obelisk on Mont Pelee 38

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

,, Harvard College ... ... ••. 241

,, Lowell 24'

„ Paris ■ -;43

• Old Riddle and the Newest Answer," bv

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

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

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

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

,, In Surrey ... ... ... ■. 268

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

Paca-rana ...

Palolo Worm, The

Panorama Military Telescope ..

Paradise, Birds of, in England

Parasitism, The Development of

Patents, Recent ... . . . • ■•■ 23,

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

Pelee, Mont

Penguin, The Emperor ... ....

Pericin, Dr. F. M., on Indigo

Pheasants, Hybrid

Photographic .Vtlas of the Moon

Sun

Photographs, Transmission by Telegraph

,, ' Animated, of Plants

,, Of Solar Granulations ...

,, With the Yerkes Telescope

Photography of Electric Sparks

,, Registration of Star Transits by

,, In Natural Colours

,, Pure and .Applied

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

,, Deterioration, Book on
Physiology at the British Association

,, Primer of ...

Plants, Animated Photographs of

Plover Kill Deer

Pond Life Tanks ...

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

Preserving Specimens for Microscope ... 47

Primeval Instincts

Printing Telegraph

Protective Resemblance of Insects

Protyle : What is it ?

Pvcraft, W. P., on Osprey Plumes

(See Ornithological N
Coloration of Nestlina; Birds

Q-

Qnaggas and Wild A.^jscs

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

268
71
177
267
114

lOI

6
96

175
38
98

253

160

55
83

12 2

124

286
17
99

163

204

238

83
187

7fi
282

■ 76
42
18

51
80

128

tcs.)
271

293

Radiation, A Novel Phenomenon

,, In the Solar System

266

,, Variation in Solar ...

186

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

07.

248

,, Bacteria and

127

,, Of Chemical Reactions

282

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

■'J7.

126

,, Chlorophane and

,, .-^nd Heat

,, Emanation ... ...

126

,, Book on ...

133

,, Electroscope

184

Rainfall Last Year

Ramsay, Sir W., on New Gases and Radium

Ravens Nesting in Captivitv

126

Rays, " N," '

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

245

Reade, T. Millard, " The Evolution of Earth

Structure "...

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

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

15-

162

,, Classification of ...

Resemblance of Insects ... ...

51.

137

Roberts, Dr. Isaac, Death of ...

184

Royal Society Medals ...

295

Rubber, A New Plant ;.

220, 266,

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

Salmon in Fresh Water ...

Saltness of the Dead Sea

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

Satellite

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

Saturn

School on the Ocean

-Scintilloscope

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

,, ,, Grevy's Zebra

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

Sea, Saltness of the Dead

Sea Sickness, Apparatus for Preventing

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

Secondary Battery, Patent

Sedgwick, .\dam ...

-Selenium, Conductivity of

Sensitive Plant, Photo of

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

Shark, An English

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

Shimose

Single-Phase Motor

Smell, N-rays and

Smithsonian Expedition to Observe the 1900
Eclipse

Snake Formation in Constellations •••227-,

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

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

,, Cannibalism in 222

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

296

223

119

287

159

20, 266, 287

264

236

59
170

258

160

158
24

158

93
92

159
301

293

KNOWLEDGE & SCIENTIFIC NEWS.

Vll.

Sociology, Variability in
Solar-activity and Magnetism

,, Atmosphere

,, Eclipse of 1900

,, Granulations

,, Parallax

,, Photometry

,, Radiation, Variation of .

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

Spencer, Herbert,

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

,, Double, Measure of

,, Catalogue ...

,, Spectroscopic Binary in Pegasus

,, an Interesting" Variable .

,, Colour of \'ariable

,, of Secchi's Third Type .

,, ,, Fourth Type

,, Binary
Stars, Radial Velocities of

,, Secchi's Fourth Type .

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

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

,, Projection

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

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

,, Mechanical State of the

,, Photographic Atlas of

,, Electric Equilibrium of the
Sunspots ...

,, and Terrestrial Magnetism ..

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

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

Telegraph, Printing

,, Transmitting Photographs

,, Wireless

Telephone, Wireless
Telescopes, Large v. Small

,, "Panorama" Military

I'AGi-;
214
291
150

159
122

■5^
1"
186
187
206

94
16

159

284

■ 1.'?

116

148

96
123
12^
I.S8
186

158

1 8

70,

12-?

26'l

9
17

q2
127
2g6

89
160
201
184

119

186

I.ST
96, III)
265, 290

4.=;

iqi

18
56

72
160

K. 12 40

Teletyping

Temperature, Mean
Thylacine, The

Tibetan Animals ...

Touracon, A Nestling

Traction System, Electric

Transmission of Photographs by 'lelcgraph

Turbines, Patent ...

Turkeys, Brush, Breeding in Conlinenicnt

i'.\r.K
IS

.S9

216

292

49. 73

23
24.3

Variability in Sot-iology ...

214

W-locities, Kadi:il, of Stars

of I he Piei.ides

TS7

X'enus, Observ.-itions on

\"ipcrs' Poison

1 89

X'olcauic Obelisk ...

. iCk),

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

,, Plant, Photo

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

,, Destruction of

Wind-driven filectricity Works
Wireless Telegraphy Experiments

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

Elephants ... ... ... II

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

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

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

Stars 186

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

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

131

24, 50, 76
84

1 66
42
96

125
36
72

246
10

•77

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

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

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

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

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

Zoological Notes

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

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

Vlll.

KNOWLEDGE & SCIENTIFIC NEWS.

ILLUSTRATIONS.

PAGE

Aeroplane..

III, ii3> 154-5

Animated Photographs of Plants

83-86

Arctic Exploration

192

Rricteria and Radio-activity

127

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

197

„ Henry, Portrait of

204

nirds, Nestling ...

273

Biitternies "

... 52, 137, 210

Camel, Ancestry of the ...

Cancer, Discovery

15. .^9

Capo Jumping Hare

170

Carnivora?, Ancestry of the

Chimpanzis and Gorillas

300

Constellations, Snake Forms in

227-9

Coral Island, Borings on

33' 34

Crystals, The Birth of

183

Darwin, Mr. Francis, Portrait ...

205

Dolls of the Tombs

185

Electrical Ore Finding ...

157

Elephants' Ancestry

11-14

Eliot, Sir John, Portrait

200

Flowers, " Physiotype "

239

Fossil Coal ...

305

Fungi

...141, 231, K. 3

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

Indigo Plants

Insects with Terrifying Masks

Jupiter

Kummeter

Lamb, Prof. Horace
Lunar Apennines

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

Mars

Meteorological Charts ..

Mont Pelee, Obelisk

Nebula; of the Pleiades
Nebulosities in y Cygni

Osprev Plumes
Ovster Fisheries ...

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

Radium and Radio-activity
Resemblance of Insects

PAGE

... 67, 87

168-9

... opp. 38

289
opp. p. 10

129

177-8
203

'75
29

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

206

290

... K. 17

253
208

opp. K. 8

245

199

opp. 64, 65

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

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

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

Wind-driven Electricity Works
Wright Aeroplane

Young, Prof. Sydney, Portrait ..

Zebra, Grevy's

205

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

216

37
4

259

Jaxvary. 1904.]

KNOWLEDGE.

Founded by RICHARD A. PROCTOR.

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

CONTENTS.

P*OK
1

Central Asia and Tibet

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

Modern Cosmogonies. VI.— World Building out of

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

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

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

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

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

tetters :

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

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

A Foo Bow. By Maey Fraseh 13

Obituary;— Hebbebt Spencer 13

British Ornithological Notes. Conducted by Haeet F.

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

Notes 13, 22

Notices of Books 14

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

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

trated) 10

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

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

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

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

CENTRAL ASIA AND TIBET.*

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

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

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

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

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

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

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

line Hence I had to keep my eyes upon the

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

rippling song to the irrespimsive sand Very

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

KNOWLEDGE.

[January, 1904.

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

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

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

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

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

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

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

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

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

1904.]

KNOWLEDGE

FUNGI AS LINKS IN THE CHAIN OF LIFE.

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

By G. Jl.vssEE.

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

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

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

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

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

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

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

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

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

'., * m '^

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

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

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

KNOWLEDGE.

[January, 1904.

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

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

fihlM^.

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

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

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

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

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

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

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

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

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

Jantary, 1904.

KNOWLEDGE

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

KNOWLEDGE

[Jantjaby, 1904.

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

MODERN COSMOGONIES.*

VI.— WOllLD-BUILDING OUT OF METEORITES.

By Agnes M. Cleeke.

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

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

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

■f The Sew Astronomy, p. 197.

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

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

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

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

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

Jakuaky, 1904.]

KNOWLEDGE.

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

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

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

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

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

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

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

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

KNOWLEDGE.

[January, 1904.

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

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

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

JUPITER AND HIS SURFACE CURRENTS.

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

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

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

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

r 1 ^ ' 1

m 1 1 ■

1 ' 'I ' 1

L 1 '

1 ^

..\,

W
H

Oh
O

i<3 .-

Janiaby, 1904.]

KNOWLEDGE.

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

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

No.

Latitude.

Rotation
Period.

Kemarka.

1 I +80° to +31°

2 I +J4'' to +2*°

b. m. s.

9 55 37-5

f9 ot .30 )

1 9 56 30 (

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

+21° to +20°

48
49

30 J

S. component of N. Temp. belt.

+ 20° to +10°

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

+ l<i° to-12«

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

-12° to -lt°

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

- 12° to -18°

S. component of S. Equatorial belt.

-14° to-2'?>

.=»

Great Ked Spot.

- 18° to - 36°

.55

18-5

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

-30° to -50°

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

- .^iJ" ±

Ed^re of S. Polar sbadinf^.

These cun-ents must be discussed more in detail.

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

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

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

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

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

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

KNOWLEDGE

[jANUARy, 1904.

Number of Spots
observed.

Rotation

Period

h. m.

9 50

24-2

9 50

24-7

9 50

237

9 50

28-6

9 50

27-8

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

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

ITear.

1898
1899
1900
1901
1902

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

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

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

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

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

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

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

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

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

January. 1904.]

KNOWLEDGE.

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

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

The accompanying diagram will enable the reader to

5 STcmperaIn Zone
5 TempcraJe Zone
5 Tropical Zone

Equatorial Zone

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

S Polar Shadinq
.^ S.Temperate Belt

^S.Tefnperate Bell

SEquatonal Bell

Equatorial Band
N Equatorial Belt

N Temperate Bel I
N N Temperate Bell

N Polar Shading

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

THE SHOWER OF LEONID METEORS IN 1903.

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

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

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

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

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

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

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

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

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

Ellison, Rev. W. F. A., Enniacortlnj.—lUi. 45iii. to
12h. 45m., 5 Leonids; 12h. 45m. to 13h. 45m., 16 Leonids;
13h. 45m. to 14h 45m., 36 Leonids; 14h. 45m. to 151i.,
11 Leonids; loh. to 15h. 15m., 0 Leonids! Three fireballs
seen, 13h. 40m., 153' + 43° to 185' + 28° (Taurid) ;
13h. 58m., 160=" + 18° to 166° + 12° (Leonid) ; and
14h. 19m., 210' -|- 65° to 273° + 58P (Leonid).

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

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

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

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

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

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

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

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

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

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

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

observed.

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

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

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

KNOWLEDGE,

[January, 1904.

Point of radiation. loD^ + 22^°.

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

Hcttrrg.

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

LARGE VERSUS Sil.lLL TELESCOPES IX
PLANETARY WORK.

TO THE EDITORS OF KNOWLEDGE.

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

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

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

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

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

THE ORCHID CEPHA.LANTBERA GRANDIPLORA.

TO TBE EDITORS OF KNOWLEDGE.

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

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

Fig. 1.

Fig. 2,

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

24, Iffley Road, C. E. Clark.

Hammersmith, W.,

November 16th, 1903.

Janvary, lOOL]

KNOWLEDGE.

A FOG BOW.

TO THE EDITORS OF KNOWLEDr.E.

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

Beckley. Mary Frasek.

i3'b\t\xatv.

HERBEKT SPENCER.

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

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

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

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

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

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

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

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

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

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

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

i^otcs.

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

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

KNOWLEDGE

[Januaky, 190i.

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

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

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

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

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

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

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

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

I^otfccs of Boons.

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

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

Jasu.ujy, 1904.]

KNOWLEDGE

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

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

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

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

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

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

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

KNOWLEDGE.

[January, 1904.

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

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

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Direction of Bair in Animals and Men. By Walter Kidd, M D.,
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The Cosmos and the Creeds. By Capt. AT. U=borne Moore.
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The Sir/ns of Life. By Augustus D. Waller, M.D , F.R s. (Murrav.)
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Essai/s and Addns.^es, 1900—li)0:i. By the Et. Hon. Loid
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/School Oeometri/. Part V. By H. S. Hall, Ji.A., and F. H
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St Anselm. Froslogivm ; Monologium ; An Ajpendix in lehalf
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Evolution and Adaptation. By Thom.as Hunt Morgan, TH. u.
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Fducaiion .- Intellectual, Moral, and Physical. By Herbert
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Annual llej^ort of the Smithsonian Institution, 1902.

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

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

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

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

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

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Eoss Limited Abridge Catalogue, 1903.

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THE ANCESTRY OF THE HORSE.

By E. Ly'dekkee.

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

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

After this inspection of the skeleton of the tapir, we

Januarv, 1904.]

KNOWLEDGE.

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

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

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

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

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

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

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

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

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

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

KNOWLEDGE

[Jakcaby, 1904.

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

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

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

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

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

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

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

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

Januaby, 1904.]

KNOWLEDGE.

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

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

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

Passing on from certainty to conjecture, it is probable

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

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

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

KNOWLEDGE.

[January, 1901.

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

MICROSCOPICAL RESOLUTION.

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

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

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

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

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

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

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

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

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

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

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

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

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

Jascasy, 1901.

KNOWLEDGE.

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

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

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

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

NOTKS AND QUERIES.

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

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

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

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

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

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

KNOWLEDGE.

[Januaby, 1904.

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

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

THE FACE OF THE SKY FOR JANUARY.

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

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

Sunspots may now frequently be observed.

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

The Moon: —

Phases.

H. M.

Jan. 3

O Full Moon

5 47 A.M.

(T Last Quarter

9 10 P.M.

., 17

% New Moon

3 47 P.M.

„ 25

]) First Quarter

8 41 P.M.

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

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

Disappearance.

Beappearance.

c 6

4«

a
Is

a .

5»

•<
m

g
o

h. m.

1 °

b. m.

d. h

Jan. I in Tanri I o-2

6 8 P.M.

129

170

6 49 P.M.

214

2,V!

13 21

„ 3 26 Gemiuorum

.VI

1 34 A.M.

1 66

, 2 .32 A.M.

««

274

15 4

., 5

o LeoDis

a-8

1013 P.M.

129

167

11 9 p.m.

2.i9

?,95

18 1

■ > 26

D.M + 12°436

,=«■!»

7 19 P.M.

, 2.i

8 11 P.M.

:iO!»

ifSl

9 4

>. 28

B.A.C. 15215

5-8

6 16 P.M.

'. 7U

1 7 28 P.M.

271

11 3

„ 30

A Geluinoram

3 6 A.M.

106

4 3 am.

275

234

12 11

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

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

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

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

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

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

Bay.

West.

East.

Day.

West.

East.

3 2 O 1 4

3 O 1 2 4

3 1 O 2 4

2 O 3 4 •

1 O 2 4 •

2 10 3 4

2 O 1 4 3

O 1 2 3 4

J O 4 3

1 3 O 2 4

4 O = 2

3 2 O 4 1

4 3 1 O 2

3 4 1 2 O

4 3 2 O 1

4 3 O 1 2

4 3 1 O 2

4 2 1 O 3

4 ® 2 •

4 2 0 3

4 2 O 3 •

4 O 1 2 3

4 2 1 O 3

4 1 ® 2

4 O 1 3 2

4 3 2 O 1

I O I

3^20

3 2 O 1 4

3 O J 2

3 1 O 4 •

Tlie circle (O) represents Jupiter ; 0 signifies that tlie 9at«llite is
on the disc ; • signifies that the satellite is behind the disc, or in the
shadow. The numbers are the numbers of the satellites.

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

cannot be observed.

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

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

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

respective positions on the 16th being : —

Right Ascension. N. Declination.

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

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

26^

24"

^ o"

1 b"

-^-,-^

■

••

— t. \

•

■

.• i.

•

^r^

k22

« .

•

■ ••

. •

^^l

•

-6-

C4."

C l""

-■"

.-^^l

Chart showing path of Xeptune in 1904.

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

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

KNOWLEDGE.

Metror Showers :-^

Date.

Badiout.

Name.

Clmraoteristiis.

R.A.

Deo.

Jan. 2-3

230
21)5

+ 53
+ 53

Qviadrantids
K Cygnids

Swift ; long patlis
Slow ; bright

South

West

East

North

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

Zenith . Perseus, Auriga (CapeUa).

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

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

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

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

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

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

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

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

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

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

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

Diagram of c Orionis.

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

dbfss (Column.

By C. D. LococK, h.a.

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

l\itions of Dec'euiber Problems.

No. 1 (W. Geary).

K,;y-moi!fi.—\. B to B7.

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

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

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

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

If 1.
1.

No. 2 (C. D. Locock).

Key-move. — ]. Kt to K8.

. K to B4, 2. Q to R7.

. KtoK6,orKt6, 2. QxPch.

Solutions received from "Alpha," 4, 4; W. Nash, 4, 4;
G. A. Forde (Major), 4, 4; "Looker-on," 4,3; G. VV.
Middleton, 4, 4; " Quidam," 4, 4; J. W. Dixon, 4, 4;
C. Johnston, 4, 4 ; H. S. Brandreth, 4, 0 ; H. F.
Culmer, 4, 4 ; T. Dale, 4, 4 ; J. Jones (Salford), 4, 4.

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

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

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

Result op Solution Tourney, 1903.

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

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

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

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

The above award will remain open for one month.

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

KNOWLEDGE.

[January, 1904.

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

PROBLEMS.

No. 1.
By A. H. Human.

Black (8).

i _..m m

M, WM ^ § i

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

M 9 m.

WniTE (P).

White mates in two moves.

No. 2.
By J. C. Candy.

Black (3).

■mm. mm

m * ^.

H H

I ■

White (5)

White mates in three moves.

SOLUTION TOURNEY, 1904.

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

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

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

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

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

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

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

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

CHESS INTELLIGENCE.

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

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

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

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

SUBSCRIPTION.— Annual Subscription, throughout the world,

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

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

Volume ; po3tage extra. Cases for Binding sold

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

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

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

Publisher of Knowledge.

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

see

UDomledge & Selentifle Neiiis

A MOXrillA JolRNAL OV SCll'NClL

Vol. I. No. i.

[new SERIES.] FEBRUARY, 1904.

r Entered at "i
LStalioners' Hall. J

SixPKNCE. By Post, 7id.

Introduction.

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

Ancient Calendars a^nd
Constella^tions.

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

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

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

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

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

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

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

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

By the Hon. limme-

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

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

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

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

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

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

(2) This date accortls with the tradition of the

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

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

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

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

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

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

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

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

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

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

Feb., 1904.]

KNOWLHDCIK c^- SCII'XTIFIC NEWS.

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

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

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

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

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

A Motor AeroploLFve,

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

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

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

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

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

A Wright Machine— A side view.

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

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

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

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

^.^^^^^
Electrical Novelties-

Giant and Miniature
S\ins.

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

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

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

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

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

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

Feb., 1904.]

KNOWLEDGE i^- SCIENTIFIC NEWS.

the distance of Aldebaran. Hence the real brightness of

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

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

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

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

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

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

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

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

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

Ceylon
Pearl Oyster Fisheries.

Professor Herdman's Report to
the Colonial Government.

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

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

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

Feis., 1904.]

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

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

iNative Divers employed by l*rof. Herdman.

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

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

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

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

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

lart^e shell, is about a month old.

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

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

One (tf the enemies

Half natural si/e.

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

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

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

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

Three transplanted Oysters showinjj rapid growth. I

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

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

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

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

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

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

Astronomical Notes*

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

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

As regards pearl -formation, some pearls or pearly

Sir W. Ramsay on New Gases and Radium.

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

Feb., 1904.]

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

5olar Activity and Terrestrial Magnetism.

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

Stellar Magnitude of the Sun.

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

Double Spiral Structure in Hercules.

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

Botanical Notes.

A New Rubber Plant.

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

A New (ienus.

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

Root Formation.

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

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

British Orrvithological Notes.

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

REVIEWS OF BOOKS.

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

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1 904.

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

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

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

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

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

The SoLltness of the
Deocd Sea.

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

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

The Nebulosities round
/ Cygni.

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

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

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

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

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

NORTH.

THE NEBULOSITIES ROUND v CYGNI.

—

Feb,, 1904,]

KNOWLEDGE cS: SCIENTIFIC NEWS.

The Ancestry of the
Elephants,

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

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

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

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

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

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

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

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

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

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

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

I'bil. Trans , 19031;,

Section lb.

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

Tep.., 1904.

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

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

(fig- 3^)-

There is not much doubt that, with so remarkably

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

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

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

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

tooth (B). — Middle Miocene; Europe.

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

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

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

Some of the short-chinned species which form the genus

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

fYW\)

Fig. .?b.

Feb., 1904.]

KNOWLEDGE & SCIENTIFIC

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

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

(All figures much reduced, as indicated by fractions.

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

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

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

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

Fig. 5a.

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

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

The Latest Discovery
Concerning CoLrvcer.

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

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

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

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

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

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

Feb., 1904.]

KNOWLEDGE & vSCIENTIEIC N1«:WS.

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

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

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

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

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

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

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

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

Zoological Notes.

liy R. LVDEKKEK.

Similarities of Elephants and Dugongs.

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

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

KNOWLEDGE .^ SCIENTIFIC NEWS.

[Feb., 1904.

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

Classification of Reptiles.

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

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

Duration of Pregnancy in the Badger.

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

Evolution of Marsupials.

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

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

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

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

Death of Prof. Karl von Zittel.

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

The Electric Eye,

Curious Experiments with Electric Sparks.

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

A further modification was the introduction of a square

Feb., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

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

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

The Altimeter.

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

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

Continental Physical
Notes.

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

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

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

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

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

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

\V ega
6 X io"\

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

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

St.ir.

Maenitudr.

Illumination in I.ux

Sun . .

.. - 20-6 .

. I2O'0O0

Moon

.. - I3'2 .

0'2

Star first maKnitude

.. + I

I '05 X 10-"

Star sixth maHnitudi.-

.. + 5

97 X 10-''

Star fourteenth magnitude

.. -+- 14

(j& X 10 -12

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

Electric DischaLrges in the Air.

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

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

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

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

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

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

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

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

The Printing Telegraph

The Berlin Teletyping Central Station.

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

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

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

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

Feb., 1904.]

KNOWLEDGE cS: SCIENTIFIC NEWS.

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

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

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

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

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

The Face of the Sky for
Febrviary.

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

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

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

Date.

Axis inclined to W. from
N. point.

Centre of disc, S of
Sun's equator.

I-

5 •-

13°

38'

6°

21'

15 ••

17°

20'

6°

52'

■•

25 ■■

20-

28'

10'

The Moon : —

Phases.

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

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

33 P-m-
56 a.m.

5 a.m.

9 a.m.

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

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

D. H.

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

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

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

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

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

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

Day.

West. ' East.

Day.

West.

East.

1034

24O13

2O134

i043«

0234«

0324

1O324

32O14

321O4

31O24

3O124

3O1*

13O24

1023

2O134

42C13

12O43

4023«

4O1S

41O32

432 o«

432 0 1

4321O

4321 0

43O5

43O12

413O2

4i02«

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

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

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

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

Meteor Showers : —

D'BJram Illustrating Occultation ol Aldebaran.

Radiant.

Date.

R A.

Dec

Near to.

Characteristics.

Feb. 5-10

.. 15
20

75'
236
iSl"

+ 41"
4- 11"

+ 34"

7;.'\urigae
a Serpentis
Cor Caroli

Slow; bright.

Swift ; streaks.
Swift ; bright.

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

Zexith . .\uriga.

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

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

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

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

North . Ursa Minor, Draco, Cepheus, UrsaMajor

to the right of Polaris,

Feb., 1904.]

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

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

Telescopic Objects: —

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

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

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

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

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

The Showerof November Leonids in 1903.

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

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

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

Estimated magnitudes

■■ 4-^

>l — 4

Radiant point

■ ■ 151 + 25

151 -f Zi

Height at beginning

77 miles

81 miles

Height at ending . .

■ • 52 ..

60 ,,

length of visible path

■• 30 ,,

24 ..

Velocity per second . .

■ ■ '« ,,

44 ..

Observers

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

\V V D.. A. King,

Bristol. Sheffield

I W. F v..

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

January 6, 1904. W. F. Denning.

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

Magnification of Objectives and Eyepieces

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

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

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

[Feb., 1904.

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

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

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

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

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

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

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

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

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

Feb., 1904] .

KNOWLEDGE & SCIENTIFIC NEWS.

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

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

p p' f

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

P
I

P"
D +

and the ratio

D
d

P'
P

we obtain

, or more simplj' f = p'

D + d'

New Spectrometer Ta.ble.

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

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

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

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

Recent Patents.

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

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

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

London Sept. 10.

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

carbon compound, and hydrogen is passed over a suitable catalytic

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

a reaction chamber or series of chambers. The hydrocyanic acid

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

to produce a cyanide. The carbon compound may be carbonic

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

Water gas may be employed for supplying a mixture of carbonic

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

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

iron may form the catalytic agent.

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

Feb., 1904.]

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

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

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

vary an other-
in an electric

71, Huntley
LLKR, c;., 14,

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

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

FIC I

LAST YEAR'S WEATHER— FEBRUARY, 1903.

DISTRIBUTION OF MEAN TEMPERATURE.

^40

RAINFALL.

'?
L,

'J—j- ?n il.

■J 4.0 f

'^^ '°'0 'bo? 3° 58 0-99

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

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

UDomledge & Selentifie flems

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

Vol. I. No. 2.

[NEW SEKir.s]

MARCH, 1904.

r Entered at
LStationers' Hall.

si.\i'i:nci;.

Contents and Notices. See Page VH.

TKe Arvcestry of the
CoLmeL

By R. LVDEKKER.

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

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

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

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

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

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

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

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

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

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

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

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

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

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

Fig. 2.— 5lvuli of Poebrotlierium

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

Mar., 1904.]

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

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

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

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

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

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

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

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

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

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

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

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

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

KNOWLEDGE & SCIENTIFIC NEWS.

I Mar., 1904.

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

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

Here a brief diversion must be made to notice an
extraordinary North American Miocene form, which is off
the mam line. This is the giraffe-necked camel (Alti-
camdas), a creature of the size of a giraffe, with similarly
elongated neck and limbs, and evidently adapted for
browsing on trees. The feet and number of teeth were
generally similar to those of Procamelas. Unlike the
giraffe, the length of the limbs is due to the elongation
of the bones of the upper segments (femur and tibia) and
not the cannon-bones : while the fore-limbs are not
higher than the hind ones. The length of neck is due
to the elongation of the anterior neck-vertebra-; if the
hinder ones had been lengthened, the hei.ght of the body
would have been increased without any compensating
advantage. This creature affords one of the most extra-
ordinarv instances of special adaptation known to science.

The remaining space at my disposal must be devoted
to certain considerations concerning the birth-
place and geographical distribution of the group.
It is claimed by Transatlantic pahfontologists
that North America was the original home of
the Camelidii, and so far as the earlier members
of the group are concerned, there is nothing at
present to justify a contradiction of this. The
case is, however, \-ery different with the latter
forms. We have seen that in North America
the formation of a complete cannon-bone did
not take place till tlie Pleistocene, at which
epoch true camels also made their first appear-
ance. But such camels, with complete cannon-
bones, were in existence in India in the early
pliocene. Ob\ iously, therefore, the evolution ot
these animals must have taken place somewhere
in Asia; this \iew being supported by the oc-
currence there of the aforesaid Pnraeamelas.
1 lence it is quite probable that some of the
earlier stages of the evolution of the group may
have been carried out in ;\sia, when that conti-
nent was united by way of Pehring Strait with
North America. The Siwalik camel, it may be
added, may ha\'e gi\en rise totlie existing two-
humped Bactrian species ; while from the ex-

tint t Russian and Roumanian camels the single humped
Arabian species may have sprung.

W'ith regard to the llamas of South America, palaeonto-
logy goes to prove that the ancestral forms first
obtained entry into that contintent from the north dur-
ing the Pliocene period, when free communication
was established between North and South America.
Now all these ancestral forms, of which there are several
distinct generic types, appear to have complete cannon-
bones. Consequently, unless we are prepared to admit
that these compound bones have been independently
evolved in the camels and the llamas, the latter cannot
have been derived from the known North American
Pliocene forms, in which the union of the constituent
elements of these compound bones was incomplete.
Consequently, it seems a probable supposition — and this
is supported by the above-mentioned structural resem-
blance between the cheek-teeth of the Siwalik camel and
those of the llamas — that the latter animals, like the true
camels, were evolved in Eastern Central Asia, whence
they reached South America by way of the Pacific
border of the northern half of the New World, possibly
over land long since submerged.

The PKotogroLphy of
Electric Spa^rks.

The Photography of Some Electrical Phenomena
was the subject of a lecture delivered on January 25,
1904, at the Camera Club, Charing Cross Road, by Dr.
George H. Rodman.

The lecturer commenced by describing t!ie method
that he had adopted in obtaining the photographic repre-
sentation of electric sparks from a lo-inch induction coil
actuated by accumulators. It seemed to matter but little
what voltage was used in the primary circuit, and the
results shown were produced at a voltage varying from
fi to 24 in the primar)'.

Single Fo.siiive Di.scharge.

Mar., 1904.]

KNOWLEDGE c^- SCIENTIEIC NEWS.

Sinsjle and multiple discharges were discussed ; the
former occupying a very short space of time, possibly

about of a second. Numerous representations of

20.000 '^

sparks taken under different conditions were shown, and

Single Discharg:c bL-twccn Points.

attention was called to the marked difference between
the positive and negative discharge, the former having a
brush-like appearance, and the latter invariably showed
a characteristic fern-like representation on the plate.

The lecturer showed excellent examples of the in-
creased intensity of the spark when a spark gap was
introduced into the secondary circuit, and in passing re-

.Single Positive Discharge on Florir.

marked that this was the e.xplanation of the use of a
spark gap employed in connection with the sparking
plug of motor vehicles.

Examples of sparks from brushes and spheres, in addi-
tion to ordinary point discharges, revealed many extra-
ordinary effects ; and in all the characteristic features of

the positi\e and negative discliarges were invariably
present. The results. Dr. Kodman cxphiined, were
obtained on Imperial platfs, wliicli were subsiMiuentiy
developed in the usual manner with a pyio suda
solution.

The production of the photographic image of
coins placed on the surface of the emulsion, and
connected up with one or other terminals of
the coil furnished some highly interesting
results; and in these cases the characteristic
features of the positive and negative discharges
were well shown.

On passing a single discharge on these coins
with subsequent development of the latent
image, a very distinct representation of the coin
with its inscription clearly legible was produced,
and the same effect was obtained in a much

Single Negati\e Discllarge on Coin.

clearer manner when a multiple discharge of
current extending to i-2oth sec. was used.

In this experiment when a discharge was
produced with two coins attention was called
to the remarkable appearance that the plate on
development presented — the image of botli
coins being multi])le. Dr. Rodman stated that
he had up to the present been unable to deter-
mine the cause of these multiple images, and,
in order to arrive at a conclusion as to the
cause of these nimbus-like shadows, had adopted
various devices, but had failed with them to elucidate
the matter.

Assuming that they were the result of reflection, films
had been used instead of the glass plates employed in tlie
other experiments. Backed plates had also been made
use of, but the multiple shadows still presented them-
selves. To exclude the possibility of their being pro-

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

duced by retiection from the edf,'es of the coins, these
had been painted with non-actinic colour.

Finally, it was thought that the coins might have been
thrown into a state of agitation, and had mo\-ed daring the
passag'e of the current, and to exclude this possibility

trend taken by speculations as to its origin. They have
become more subtle, more far-reaching, yet less confi-
dent. They have ramified in unexpected directions, but
rather tentatively than with the full assurance of attain-
ing absolute truth. Laplace considered only the solar
system, from which he arbitrarily e.xcluded
comets ; on the \ast sidereal world he
bestowed barely casual attention. Sir
William Herschel, on the other hand,
occupied himself exclusively with the
growth -processes of nebuUf, relegating the
details of planetary evolution to a position
of secondary importance. Later, the spectro-
scope having become available for dis-
criminating generic difl'erences among the
suns in space, their relative ages, the order
of their succession, their mutual affinities,
laimed predominant attention. Just now.

Sinj^le Positive Oischarge on two Coins. Both Coins in .Spherical Connection.

they had been enclosed and supported in a couple ot
circular holes made to fit the coins in a card at the time
of exposure. This peculiar feature of the experiment
was met with when coins of unequal size and of varying
metals were employed, and was also noticed when the
glass insulating plate was replaced by an india-rubber
pad.

Modern Cosmogonies.

VII. Cosmogony in the Twentieth
Century.

By Miss .\gnes Clerkk, F.K.A.S.
pROSPECTl\E and retrospectix e inquiries into physical
conditions stand \ery much on the same footing. The
same degree of uncertainty attaches to results of both
kinds ; the same qualifications need to be applied to
them ; a similar reserve is understood to accompany our
admission of them. The reserve grows more marked
as science unfolds to our surprised apprehension the
multiplex possibilities of Nature. The time has gone by
when " men of light and leading " could draw cheques
for unlimited amounts on the bank of public credulity.
Not that the balance has diminished, but that it is other-
wise employed. Most of us, in these days, have learnt
to "look before and after" for ourselves; and we in-
stincti\ely mix the pr(j\erbial grain of salt with what is
told to us, even on the highest authority. Ideas are on
the move ; dim vistas are opening out ; much that lies
lieyond the verge of actual experience is seen to be
possible, and sedate reasoning may at any moment
suffer outrage by fantastic discovery. Hence, dogmatism
is at a discount.

The secular parallax allccting men's views of the
universe is nowhere more strongly apparent than in the

however, the flood of ideas is too high to
be restrained within separate channels ;
cosniogonists look far afield ; they aim at
obtaining a general sur\ey of relations
baffling in their complexity. To some ex-
tent they have succeeded ; parts are
beginning to find their places in a great
whole ; links are seen to connect phenomena
at first sight seemingly isolated ; on all
sides, analogies are springing into view.
The unwearied circling of the moon, and its
imperturbable face, remind us how a sun
may have been born ; the fiash of every
meteor suggests the mode by which suns die.
The filmy traceries of comets intimate the nature of the
force acting in nebulae ; the great cosmic law of
spirality is distantly hmted at by the antipodal disturb-
ances of the sun. Thus, one set of facts dovetails
into the next ; none can be properly considered apart
from the rest.

The limitations of the human mind, nevertheless,
require a subdivision of labour. Individual efforts can-
not grapple with the whole of the known and the know-
able ; and the larger part of both is included in the scope
of modern cosmogony. It deals with all that the skies
hold, visibly or invisibly ; draws unstintingly on time
past and time to come ; concerns itself equally with
gradual transformations and sudden catastrophes, with
the dissipation and concentration of energy, with the
subtle interplay of matter and force, with physical and
ultra-physical, chemical and electrical modes of action.
But let us consider a little more particularly how things
actually stand, so as to collect some definite ideas regard-
ing the lines of advance practicable and promising for
the immediate future.

To begin with our domestic circle. The insecure state
to which Laplace's scheme has been reduced by the
assaults of numerous objectors has found compensation
in the development of tidal theory. Much light has
thereby been thrown upon planetary pre-history. The
relations of planets to the sun, and of satellites to planets,
have been rendered comparatively intelligible. Notice-
able above all is the discovery thence ensuing of the
earth's critical situation, just outside the boundary of the
region where planetary rotation was destroyed by sun-
raised tides, and with it the prospects of planetary
vitality. Moreover, the consequent dubious state of the
inchoate terrestrial spheroid accounts for the peculiar
mode of birth of the moon, and the distinctively binary
character of the earth-moon system; while the variety
perceptible in the circumstances of the different planets
precludes the employment of any single recipe for their

Mar., 1904.]

KNOWLEDGE c\: SCIENTIFIC NEWS.

development from a primal vortex. The forces concerned,
we can now see, acted in a far more complex manner
than could formerly have been supposed ; and their
balance was proportionately more delicate. To which
side it would have inclined in a given case must tiien
often be incalculable, or calculable only with the guid-
ance of the known result. The strict bonds of reasoning
have tlius become somewhat relaxed, and difficulties tiiat
looked formidable have, in the long run, proved not to
be insuperable. But conviction has also grown faint.
The old, imposing fai;ade of theory remains erect ; the
building behind it has been for the most part pulletl to
pieces, and the architect has yet to be found who can
reconstruct it to our satisfaction.

On one point we have, nevertheless, acquired certainty.
It is now known that comets with their dependent trains
of meteors are aboriginal in the solar system. They are
no unlicensed intruders, but collateral relations of the
planetary family. Possibly, they represent waste scraps
of world-stuff which escaped the action of the formative
machinery ; and if so, they exemplify its primitive tex-
ture. Not that their composition need be, on this sup-
position, identical with that of the planets. A sifting of
elements would have been likely to accompany the pro-
cesses of cooling and contraction. Comets were perhaps
made (so to speak) of the white of the nebulous egg,
planets of its yolk. But in any case, we may safely
regard the glimmering fabrics of acetylene and cyanogen
that occasionally illuminate our skies as shearings from
a wide-spreading, fleecy haze, flung aside before " the
starry tides " had as yet begun to " set towards the
centre." In one respect, the quality of these relics is
a surprise. They show no chemical affinity with
nebula?. Their spectra are radically different from
nebular spectra, gaseous or continuous. They accord-
ingly lend no countenance, although not fatally adverse
to the view that the sun was once, in the distinctive
sense, a nebulous star.

The grand topic of sidereal succession is no longer
abandoned to fruitless surmises. Broad lines have been
laid down, along which — so far as we can at present see
— progress must inevitably have been conducted. And
one fact of overwhelming significance in this connection
is entirely of recent discovery. The multitudinous
existence of obscure bodies in space had, indeed, been
foreseen as a logical necessity long before Bessel founded
the " Astronomy of the Invisible" ; but it has been sub-
stantiated almost wholly by modern spectrographic
methods. Decrepit or dusky suns are assuredly no
imagmary product, but a potent reality ; though it
would be too much to assert that all have sunk to
extinction by the same road.

We stand, too, on firmer ground than our predecessors
in respect to the history of stellar systems. That its
course is mainly prescribed by the influence of tidal
friction has been ably demonstrated by Dr. See. Tele-
scopic double stars can be led back, by the aid of this
clue, to an initial stage, when they revolved close
together, very much like the earth and moon in Professor
Darwin's theory ; and it was owing to their v oluminous-
ness, and the unequal attractions it engendered, that
their orbits became enlarged and elongated to the degree
generally observed. Spectroscopic binaries, moreover,
illustrate earlier modes of circulation ; they present us
with couples fully separated, and still separatmg, as well
as with others barely divided, and revolving almost in
contact. Nay, they include specimens, we are led to
believe, of globes conjoined into the apioidal figure
theoretically investigated by Darwin and Poincare,
which may be regardedas preparatory to the dev elopment, '

by iission, of two mutually revolving stars from one
primitive rotating mass. One of these supposed dumb
bell systems is the variable V Puppis ; and if tlie eclipse-
rationale of its obscurations be confirmed by the spectro-
scope, there is no gainsaying the inference that it is com-
posed of two stars actually contiguous, if not commingloil.

Now compound stars are by no means of exceptional
occurrence. Their relative abundance has been found
to augment rapidly with every advance in our knowledge
of the lieavens. From the measures of stellar radial
velocity lately carried on at the Ycrkes Observatory by
Professors l'"rosl and Adams, it appears that the propor-
tion of binary to single stars considerably exceeds Pro-
fessor Campbell's earlier estimate. Of those giving
helium-spectra, at any rate, there are most probably as
many of one kind as of the other. But why the distinc-
tion, it may be asked ; and the answer is not far to seek.
Helium-stars are the most primitive, and form the
closest, and most readily apparent systems. A
physically double star must always remain such.
There is no law of divorce by which it can put away its
companion, although their relations must alter with time.
But their alteration tends continually to enhance the
difficulty of their detection. For as the members of a
pair are pushed asunder by tidal friction, their velocity
slackens, and the tell-tale swing of their spectral lines
diminishes in amplitude, and finally, by its minuteness,
evades observation. And since the majority of spectro-
scopic satellite-stars are very imperfectly luminous, their
eventual telescopic discovery, when far enough away
from their primaries to be optically separable from them,
would rarely ensue. It must then be concluded that half
the stars in the heavens (let us say) broke up into two or
more bodies as they condensed. What follows? Well
this. Half the stars in the heavens were, from the first,
incapacitated from becoming the centres of planetary
systems. To our apprehension, at least, it appears
obvious that a binary condition must have inhibited the
operations of planetary growth. These innumerable
systems are doubtless organised on a totally different
principle from that regulating the family of the sun. The
Nebular Hypothesis, even in its most improved form, has
no application to them ; the Rleteoritic Hypothesis still
less. Mathematical theories of fluid equilibrium, com-
bined with a long series of changes due to tidal
friction, afford some degree of insight into the mode of
their origin and the course of their development. Yet
the analogy with the earth-moon couple, which irre-
sistibly suggests itself, is imperfect, and may be mislead-
ing, owing to the wide difference in state between plastic
globes approaching solidification and sun-like bodies,
radiating intensely and probably gaseous to the core.

The world of nebulae presents us with complete cycles
of evolutionary problems, which can no longer be treated
in the offhand manner perforce adopted by Herschel.
The objects in (luestion are of bewildering variety ; yet
we can trace, amid their fantastic irregularities, the
underlying uniformity of one constructive thought.
Nearly all show, more or less markedly, a spiral con-
formation ;' and a spiral conformation intimates the
action of known, or discoverable laws. 1 heir investiga-
tion must indeed be slow and toilsome ; its progress may
long be impeded by the interposition of novel questions,
both in physics and mechanics ; nevertheless, the lines
prescribed for it seem definite enough to give hope of its
leading finally to a clear issue. And when at last some-
thing has been fairly well ascertained regarding the
past and future of nebulous spirals, no contemptible
inroad will have been made on the stupendous enigma of
sidereal relationships.

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1934.

Its aspect, if we venture to look at it in its entirety, is
vast and formidable. Not now, as in former times, with
a mere fragment of creation — a single star and its puny
client-globes, one of which happens to be the temporary
abode of the human race — but with the undivided,
abysmal cosmos, the science of origin and destiny con-
cerns itself. The obscure and immeasurable uncertain-
ties of galactic history invite, or compel attention. We
know just enough to whet our desire to know a great
deal more. The distribution of stars and nebulae is easily
seen to be the outcome of design. By what means, w-e
cannot but ask ourselves, was the design executed ? How
were things ordered when those means began to be em-
ployed ? How will they be ordered when all is done ? For
an ultimate condition has, presumably, not yet baen
reached. And if not, agencies must be at work for the
perfecting of the supreme purpose, which are not,
perhaps, too subtle for our apprehension. Meanwhile,
facts bearing on sidereal construction are being diligently
collected and sifted ; and we shall do well to suspend
speculation until their larger import is made known.

The inquisitions of science do not cease here. They
stri\e to penetrate a deeper mystery than that of the
scattering in space of stars and nebulie. What are they
made of is the further question that presents itself.
What is the nature of the primal world-stuff? Whence
did it obtain heat ? By what means was motion im-
parted to it ? If it be urged that such-like topics elude
the grasp of finite intelligence, and belong to the secrets
of Creative Power, we may reply that we are not entitled,
nor are we able to draw an arbitrary line, and impose a
nc plus ultra on our thoughts. Tiie world has been, by
e.xpress decree, thrown wide to their excursions, and it
is not for us to restrict their freedom. W'e need not fear
getting too near the heart of the mystery ; there is no
terminus in the Unknown to which we can travel by
express: in a sense, we are always starting, and never
get nearer to our destination. But that is because it
retreats before us. We do, in truth, advance ; and as
we advance, the mists clear, and we see glimpses beyond
of imperishable order, of impenetrable splendour. Our
enquiries need not then be abandoned in despair at the
far-reaching character they have spontaneously assumed.
From the earliest times there has been a tendency to
regard varieties of matter as derivative. They have
been supposed to be procured, by supra-mundane agency,
or by the operation of inherent law, from some universal,
undifferentiated substance. We moderns call that sub-
stance " Protyle,"" and believe ourselves to be in experi-
mental touch with it. The implications of this view we
shall consider in the next chapter.

' A term signifying " first matter," constructed from corre-pjnd-
ing (ireek words by Roger Bacon, and revived by Sir William
Crookes.

The Conductivity of Seleniunrv.

Mr. E. A. llopius, in an investigation recently presented to
the Russian Physico-Chemical Society, has made a series of
experiments with an apparatus constructed by Mr. M. Kohl
and another apparatus designed by himself on selenium sup-
plied by the firm of E. MerU, Darmstadt, the former apparatus
beinf; illuminated by a standard amy! acetate burner at dis-
tances ranging from 10-200 cm., and the other by a Nernst
lamp placed at the same distance. The measured current
intensity agreed fairly well with the hypothesis of a direct
proportionality between the increase in the conductivity of
selenium and the cubic root of the intensity of illumination.

Borings on Ql Corad
IslacHLd.

The Atoll of Fvinafviti.

Xeari.v a quarter of a century ago Charles Darwin
penned the following words in a letter to Prof. .Alexander
Agassiz : " I wish that some doubly rich millionaire
would take it into his head to have borings made in some
of the Pacific and Indian atolls, and bring home cores
for slicing from a depth of 500 or 600 feet." The pro-
found interest which Darwin had himself long previously
aroused by his theories regarding the structure of coral
reefs and their mode of origin could not do otherwise
than henceforth make the subject an integral part of
geological science, and one. too, of striking significance.
It was, therefore, to be expected that the hopeful
words of the master-naturalist would ripen with time
to bear fruit in effort. Not, however, until 1893 did

Sand iv/'t/i some cora/ b/ocks.

■M.

■52 ft. 9 in.

'■■'<a.-:

65 n.

■^

/06ft.

Cora/ reefs and blocks iv/Ch
■some se.nd.

Sand ivitb some cora/ b/ocks.

Fig. 1.— Structure of abandoned Bore.hole, Expedition i.Sc,6.

a project for such a survey become fairly launched, and
then chiefly through the strenuous endeavours of Prof.
W. J. S"illas, F. R.S., who succeeded in at last promoting a
"Coral Reef Committee." Prof. T. G. Bonney, F.R.S.,
assumed the chairmanship, and on this body several of
the most competent among English geologists, with
other authorities, consented to serve. It is unnecessary
to say that, whatever the latter-day millionaire may do
for science, none made his appearance at this initial stage.
The primary idea was to investigate, by means of a
boring, the depth and structure of an oceanic coral reef,
and thus make it tell its life story. Ultimately it was
decided to attack the problems surrounding the question
at Funafuti, an island in the Ellice Group in the Pacific
Ocean, and a comprehensive scheme for an exploring
Expedition was drawn up in i8g6. Professor Sollas
being unanimously designated as leader. Although the
difficulties that lay in front were by no means under-
rated at the commencement, yet the news of the failure
of the first attempt in 1896 was indeed unwelcome.
(I-"ig. I.) However, nothing daunted, a second Expedi-

[Mar., 1904.

KNOWLEDGE & SCIENTIFIC NEWS.

tion was organised in 181)7, under tlie diieclion of Prof.
T. \\". l-df;e\vorth David, of Sydnej', and a tliirdin i8y8,
with Mr. .\. V. Finckh as leader, for the further prosecu-

Flg, 2. — .Model of Atoll, showing tEcneral shape and Submarine contour.

tion of the work. The (inal result was the achievement
of a drill horint,' to the extraordinary depth of 1 1 14J feet,
and the hrinyjinj^ of a cor ', by which means the coniposi-

tion of an atoll in its

zoological and chemical
aspects has been actually
determined. How re-
i )ice<l the great naturalist
iif Down would ha\ebeen
(■.)uld he ha\e li\ed to
witness the realisation ul
his wish. We can pic-
I ure his eagerness to write
al once to 1 looker, and to
Wallace and .\gassiz.
I lis personal opinions re-
garding the dcNclopment
of coral reefs would not
have weighed for an in-
stant, since his open
mind had already dictated
the characteristic sen-
tence, "if I am wrong,
the sooner 1 am knocked
on the head and annihila
ted, so much the better."

Although much scien-
tific literature has centred
around Funafuti in the
inler\ening years, it has
not been possible to
pilot the whole scien-
tific story of the borings

Fijf. 3. — Hard Breccia Ma.ssts on Shore.

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

to completeness until to-day, but it is now told
in a handsome monograph just issued by the Royal
Society, to which source we are indebted for our illustra-
tions.

The configuration of the atoll is seen on reference to
the model (Fig. 2^, and its fanciful rescnblance to

the shape of a human head (view from the compass
letter S) has not escaped notice. The longest continuous
stretch of reef is 16 miles in length, and the most elevated
point abo\'e high water, 16 feet; while the general depth
of the waters of the lagoon is about 20 fathoms. One
peculiar feature of the atoll is its submarine cliflf, re-

Fig. 4.— Hurricane Beach. Fcnafuti. and li\ing "Liihothamnion " kecr.

Professor Edgeworth David

the whole atoll elevated

enable the portions

present a clift" face

Fiz- 5.— A Cluster ol the alga " Halimeda.'

garding which
remarks that were
140 fathoms, it would
above the sea-level to
300-600 feet in height.

Although we speak of Funafuti as a coral
island, in its fauna corals are the accessory
rather than the essential reef-builders, and
of the latter none aie more abundant and
contributory to reef-rock than the calcareous
algae Litlwthamnioit and Halimeda. Indeed, a
classification of the chief reef-forming or-
ganisms assigns their relative importance
thus: — (i) Species of Lithothamiiion, (2) Hali-
meda, (3) Foramiiiifera, (4) Corah. And Mr.
Mnckh, in a biological chapter, tells us, fur-
ther, that a coral once established adds to
the coral island by its growth only in the
same way as a tree once established adds
by its growth to the extent of a forest. In
the living state and by itself it cannot form
a solid mass ; dead, however, its skeleton
supplies material which the Litlwthamnion and
Halimeda unite together with the remains of
other calcareous organisms to make reef-rock
— mounting thus " On stepping stones of their
dead selves to higher things." (Figs. 3, 4.)

Some interesting e.xperimentswere conduc-
ted relative to the effect of exposure to the

1904.]

KNOWLEDGE >.^- SCII-XTIFIC NEWS.

sun's rays and the powers of endurance to lieat of
corals and of Lithothaiimion, a point on which Darwin
had speculated. It seems that except the Poiitcs, all
other forms of coral succumbed within two hours'
exposure, and it was evident that the essential life-gift
alike to coral and plant was a constant supply of fresh
sea-water.

Among the contributions to the monograph certainly
the most industrious of all is Dr. Hinde's report on his
examination of thin sections of the materials obtained
from the reef borings and those made beneath the lloor
of the lagoon. Upwards of 500 microscopic surface
slittings were prepared for diagnosis in Professor Judd's
geological laboratory at the Royal College of Science.
.\s already mentioned, the main boring, begun in 1897,
was taken down to 1114^ feet, and it may be added that
the diameters of the cores brought up in the drilling
apparatus were, top to 68 feet, about 4 inches; 68-210
feet, about 3J inches; 210 toboring limit, about 2| inches.
.\11 these cores ranged in length from i inch to 3 feet.
Dr. Hinde supplies an elaborate description of a detailed
inspection of the several lengths of core that were placed
under examination for the detection of organisms, and we
cannot do better than quote here Professor Judd s general
conclusion thereon, namely, that " from top to bottom the
same organisms occur, sometimes plants, sometimes fora-
minifera, and sometimes corals predominating ; but in the
whole depth bored the same genera and species of these
various groups of organisms take their part in the "build-
ing up of the mass." (Fig. 5).

.\ large amount of space would be necessary to even
summarize the many points of research apart from
boring and sounding operations embraced by this truly
classic exploration in the far Pacilic. There was made,
however, we must not omit to mention, a magnetic sur-
vey by H.M.S. Penguin (Captain Field) ; a series of
meteorological observations ; and a thorough study of the
natural history of the island of Funafuti.

The numerous helpers in the two continents have
reason to be proud of the evidence of their long-continued
efforts, and undoubtedly the scientific results of the sur-
vey will prove of the utmost value in current discus-
sions which concern the present-day re\ised \ iew of the
development of coral reefs.

Modem Views of
Chemistry.

By 11. J. H. Fenton, F.K.S.

It may happen that there are some of our readers who
are interested in the study of Chemistry, but who have
not had the time or opportunity of following the very
rapid and important advances which have been made
in the science, especially in the departments of physical
and organic Chemistry. In the present articles, which
are addressed to readers of this class, it is proposed to
give brief sketches in outline of some of the more im-
portant developments which have occurred during recent
years.

We will in the first place refer to the great changes
which have occurred in our views with regard to the
nature of solution and the chemical and physical changes
which may take place in dissolved substances ; the
advance of knowledge in this department has resulted in
what is sometimes called the •' New Cheniistr}-," which

would scarcely be recognised as the same science by one
who had been a good chemist twenty-livf years ago, hut
who had not kept pace with the times.

It may be mentioned in passing that it was the custom
formerly to restrict the term "solution" to liquid mix-
tures— that is to solids, liquiils, or gases dissolved
in licjuids; hut we may now speak of solutions of
gases in solids and even of solids in solids ; a solution
IS in fact, generally speaking, any homogeneous
mixture of two (or more) substances in which the pro-
portions may, within certain limits, be varied con-
tinuously. I'sually one speaks of one of the
constituents as the solvent and the other as the dissolved
substance or "solute " ; but this is only an arbitrary dis-
tinction. In the case of an aqueous solution of common
salt, for example, we might regard the mixture either as
a solution of salt in water or of water in salt; for if a
dilute solution be sufficiently cooled it becomes saturated
with respect to water, and solid water (ice) separates out,
leasing a stronger solution of salt, just as when a \'ery
strong solution is cooled it becotnes saturated with re-
spect to salt, and the latter separates in the solid state,
leaving a weaker solution of salt, i.e.. a stronger solution
of water. It was at one lime thought that solution con-
sisted in a sort of loose chemical combination between
the sohent and dissolved substance, and this idea seemed
to be supported by the fact that many salts and other sub-
stances combine with water to form definite hydrates,
which may be isolated in the crystalline form. But it
does not follow that tliese hydrates continue to exist
when the substance is in solution, and the probability is
that, in dilute solution at any rate, they do not exist.

Certain membranes exist naturally, and may be pre-
pared artificially, which will allow water to pass through
them, but will not allow the passage of dissolved sub-
stances such as sugar, salt, &c. If now one separates a
solution of sugar from pure water by means of a mem-
brane of this kind water will pass both ways through the
membrane, but more will pass into the sugar solution
than out of it, so that its volume tends to become larger
and the solution weaker. If, however, the volume of the
solution IS kept constant, that is, if it is not allowed to ex-
pand, the pressure will increase instead, and will con-
tinue to do so until a certain maximum pressure is
reached. This maximum (osmotic) pressure depends
upon the temperature, the strength (or concentration) of
the solution, and the nature of the dissolved substance. It
is found to vary with the temperature and concentration
according to the same laws which regulate the pressure of
a gas, and, further, the actual pressure produced is the
same as that which would be exerted by the same sub-
stance (theoretically in the case of sugar) if it were in the
state of gas at the same temperature and volume.

A large class of substances (such as sugar, urea, and
most other organic substances) behave, therefore, in
exactly the same way when dissolved in a solvent as
they would in the gaseous state — as regards the relations
between temperature, concentration, and pressure — only
that what we understand by " pressure " in the gas state
must be interpreted as "osmotic pressure" in the case of
solutions.

By making use of Avogadro's hypothesis— that ecjual
\olumes of gases contain, at the same temperature and
pressure, the same number of molecules — we can com-
pare the molecular weights of gaseous elements or com-
pounds by weighing equal volumes of them under the
same conditions; and now by extending this hypothesis
to substances dissolved in liquids we can compare their
molecular weights in a similar way. It may be done in
the latter case by measuring (directly or indirectly) the

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

osmotic pressure which is produced at a certain tempe-
rature and volume by a given weight of the substance.

If we apply this method to the determination of mole-
cular weights of substances in water solutions, it is found
that, although most of the organic (and some inorganic)
compounds give perfectly normal results — (results, that
is, which agree with vapour density determinations and
with general chemical considerations) — most salts, acids,
and bases give results which are apparently abnormal,
the osmotic pressure produced being too high. A dilute
solution of potassium chloride, for example, gives an
osmotic pressure almost exactly double of that to be
expected by the application of Avogadro's hypothesis.
That is to say that one molecular weight of potassium
chloride gives twice the osmotic pressure which one
molecular weight of sugar (urea, &c.) gives under the
same conditions.

It was suggested that this result might be explained
by supposing that the salt is " hydrolysed " by the
water — i.e., that caustic potash and hydrochloric acid are
produced. Since they would be formed in exactly equi-
valent quantities, it would not, of course, be possible to
detect their presence by the ordinary tests. But such an
explanation will not account for the fact that hydrochloric
acid itself behaves " abnormally " also, giving about
double the expected effect.

The theory of Arrhenius not only accounts for all these
"abnormalities," but offers in addition a most elegant
explanation of a large number of facts in connection with
the behaviour of salts and other substances in solution,
including the phenomena of electrolysis. This theory
assumes that most salts, and the strong acids and bases,
are largely if not entirely dissociated when dissolved in
water (and in some other solvents) into constituent parts
or " ions," and that these ions differ from the same sub-
stances, as we know them in the separated state, in that
they are associated with enormous electric charges. A
molecule of potassium chloride, for example, dissociates
into an atom of potassium associated with a positive
charge, and a chlorine atom with an equal and opposite
negative charge. These charges are given up at the
respective electrodes when the salt is electrolysed and
the potassium and chlorine are obtained in their ordinary
" neutral " state.

A revolutionary hypothesis of this kind was viewed,
perhaps naturally, in the first instance with suspicion and
dislike, and even at the present day it is not quite univer-
sally accepted, but the active opponents, at any rate those
who have the courage of their opinions, are becoming
daily few and far between. The application of
this ionic dissociation hypothesis in explaining various
well-known chemical phenomena is an extremely fasci-
nating study and it is proposed to give various examples
in illustration of the application at a future time, fust
one may be mentioned here in conclusion.

A question which agitated the minds of chemists for a
great number of years was of the following form: What
happens when two different salts— say, sodium chloride
and potassium nitrate— are mixed together in aqueous
solution ? Do they remain as they are or do they " change
partners," forming sodium nitrate and potassium chloride?
A large number of experiments were made with a view of
throwing light upon this question, but in most cases the
problem appeared to be incapable of solution. It was
apparently of no use to attempt the isolation of the differ-
ent salts since the equilibrium would be disturbed by their
removal, and it seemed only admissibletn employ methods
which required no removal from or addition to the solution.
Attempts were made, for example, to throw light upon
the problem by observing the thermal, volume, or colour

changes which occurred on mixing the solutions, and
although a certain amount of information was gained by
such methods, they were in most cases anything but con-
clusive.

This much-debated question then — which metal is
united with which acid-radicle ?— is (as a general case in
dilute aqueous solutions) now at once disposed of by
the ionic dissociation hypothesis, which gives the answer
— No metal is united to any acid-radicle !

Wind-Driven Electricity
Works.

l>y Dr. Ali-red Gradenwitz.

Professor Latour, of the Askov Popular Academy
(Denmark), has for some years b^en engaged on behalf
of the Danish (jo\'ernment in investigating the problem of
utilising wind power in connection with small electricity
works. If, however, the dynamo be direct-coupled to the
wind motor, the results obtained are unsatisfactory on
account of the exceedingly variable speed of the wind. As
pointed out in an address recently delivered by Professor
Latour before the Copenhagen Technical and Hygienic
Congress, he was met with difficulties in designing a suit-
able regulator for controlling the speed of the dynamo.
At present, however, these difficulties appear to have
been overcome, and an electricity central station near
Askov has been worked with wind power for a year with
satisfactory results.

The arrangement of a similar electricity works is repre-
sented diagrammatically in fig. i. The regulating device
itself is made up of two different parts. The mechanical
regulating device is intended for maintaining at constant
values the peripheric force transmitted to the belt disc of
the dynamo. The two belt discs R R are mounted on a
movable arm A, bearing a counterweight P. The
resulting tension of the belt is thus kept constant, depend-
ing on the weight of the belt discs as well as on the counter-
weight P. The ratio of the resulting belt tension and
the maximum peripheric force susceptible of being trans-
mitted by the belts is, however, practically constant.
The peripheric force transmitted by the wind motor to
the belt disc R accordingly cannot exceed a given value,
the torque of the dynamo remaining below a corresponding
value. Any surplus energy developed by the wind motor is
lost as heat with the friction of the belt. A constant torque
of the dynamo axle will, however, correspond with a
constant current intensity in the armature. In the case
of the magnetising intensity employed, the load is in fact

Fig. I.

1 004.]

KNOWLEDGE .S; SCIENTIFIC NEWS.

2,7

practically proportional to the speed, so that the intensity
of the current may be regarded as constant. This is
further demonstrated by the author's measurements.

The current from the dynamo is used to charge an accu-
mulator battery represented diagramniatically in P'ig. i.
The cut out switch F is closed, pro\ided the current in-
tensity be not inferior to its normal constant value. The
dynamo D therefore works at a variable speed. In the
case of the wind being so strong as to absorb part of the
energy by the friction of the belt, the system will work in
the following way : .\ssummg the accumulator battery to
be nearly discharged and the crank of the cell controller
to be adjusted for the total charge of the battery, llie
dynamo will run at a speed so high as to be quite suffi-
cient to charge the battery with the normal current of a
dynamo (e.g. 50 amp.). As the charge increases, the
dynamo will automatically increase its speed and load
so as to make the charging current constant. The cell-
controller will have to be resorted to in charging in
exceptional cases only — if, for instance, the charging
and discharge of the battery takes place at the same
time.

The electrical regulating device is situated in the inter-
rupter S, being mainly an ordinary minimum current
interrupter, disconnecting the dynamo as soon as the
current decreases below the normal number of amperes.
This arrangement is necessary to prevent the accumu-
lator battery from being discharged through the dynamo
when the strength of the wind is small. The interrupter,
however, will automatically insert the current as soon as
the wind again assumes a greater strength. To attain
this result, the current interrupter is provided with a ten-
sion regulator, inserting the current as soon as the speed
of the dynamo has sufficiently increased. In the case of
variable strengths of the wind, the plant may thus accumu-
late any amount of wind available, the interrupter open-
ing and closing the connections continually. On the
switchboard there are in addition two ammeters and one
voltmeter.

A small electricity works arranged in accordance with
the foregoing principle has, as above mentioned, been in
operation in Askov since the beginning of last autumn,
supplying the inhabitants of the neighbouring commu-
nities with electric current. The constant normal current
supplied by this installation is 60 amps, at tension of 220
volts. As a reserve, however, in cases of several days'
calm weather, a petroleum motor had to be installed.
The plant has so far given every satisfaction, requiring no
superintendence worth speaking of. The man in charge
of the machine was away fer|whole days, so that there
was no supervision except "Jin^^the morning and the

The W'ork.s at A.skov.

evening. The capacity of the accumulator battery is
sufficient to supply the maximum amount of energy
required during 48 hours. As regards the economical
side of the question : The (irst cost at .'VsK-on- has been
about 16,000 Kr. (a Kroner is about is. id.), out of which
3000 Kr. are set aside for the cost of pstroleum nioliir.
The electric current is supplied to consumers at the
same price as in Copenhagen. The receipts for energy
sold work out at about 2800 Kr., and the expenses al
about 800 Kr. per year. There will thus remain
2000 Kr. for the amortisation of the plant, which is more
than sufficient with a capita! of i6,ooo Kr. The price of
energy could therefore be further diminished. In ihe case
ofsniall electricity works intended for the use of a limited
number of houses, the petroleum motor may be replaced
by a horse-driven contrivance. Moreover, in the case of
the proprietor of the works being his own consumer, the
consumption of current may be regulated according to
the actual intensity of the wind; in the case of calm
weather, there will for instance have to be no thrashing
done, cVc. The first cost will thus be considcraoly
diminished; according to I'ref. Latour's calculation, a
plant suitable for a farm would be installed at a cost of
3000 to 4000 Kr.

The Canals on Mars.

Ix a communication to the Royal Astronomical Society
on June 12, 1903, as reported in the Olwrvaloi'v for July,
Mr. Maunder called in question the objective reality of
the canals on Mars, explaining them away as psycho-
logical phenomena " due to the integration by the eye
of markings far too small to be observed by the observer."
He based his argument on the fact that copies of draw-
ings of Mars without the canals, made by beys of from
12 to 15 years of age placed at \'arieus distances from the
drawings, contained lines resembling canals amounting
to five canals per head as a maximum at a distance of
25 feet, the diameter of the disk being about 6 inches.
Unfortunately, the report gives us no information as to
the closeness of coincidence of the lines with canals that
have been actually observed, nor even as to the agree-
ment between the lines drawn by different boys. It is
difficult to see hew the drawings to be copied could have
contained actual Martian markings that were " far too
small to be observed," whose integration produced lines
in the positions in which canals have been observed ;
but if the drawings were not sufficiently accurate to show
such markings, the lines must have been produced by
markings peculiar to the several drawings, whose resem-
blance to anything on the planet is highly improbable.
In drawing inferences from a comparison of artificial
experiments with natural phenomena, it is certainly
essential to the value of the results that the artificial and
natural phenomena shall be substantially identical, and
that the observations shall be made under practically the
same conditions in both cases. On a later occasion, Mr.
Maunder himself strenuously insists upon the necessity
for a very close resemblance between the phenomena and
between the conditions of observation in such cases. In
criticising Mr. Lowell's application of the results of his
experiments on the " visibility of fine lines " (the Oliscrva-
tory for September, 1903), Mr. Maunder says "there is
actually no resemblance between the case of observing a
wire in space and that of observing a line drawn on a
surface " ; nevertheless, he seems to find a sufficiently
close resemblance between the observation of a flat
picture (inaccurate, at best) with the naked eye in a

KNOWLEDGE .K: SCIENTIFIC NEWS.

[Mar., IC04.

lighted room, and the observation of an illuminated ball
surrounded by the blackness of night, seen through the
mirage of its own atmosphere by means of a telescope.
Those who draw conclusions from observations should be
very careful in their reasoning, bearing in mind that
induction, while a powerful instrument in the construc-
tion of theories, is absolutely useless in their proof or
disproof. A theory of physical phenomena can be dis-
proved only by showing that it leads by deductive
reasoning to necessary conclusions that are inconsistent
with observed facts. ;\Ir. jMaunder's theory may explain
sufficiently well the lines on the copies of his drawings,
but it no more suffices to disprove the objective reality
of the canals observed on Mars than it does to prove
that there are only fi\-e canals, as seen by his boys.
The fact that an effect may be due to one cause, while it
may certainly also be due to another, affords no pre-
sumption that it is due to the first rather than to
the second, especially when the one explanation is
based upon artificial experiments and the other is
natural.

Mr. Maunder's argument assumes that the canals are
seen as very faint lines, so faint that their existence is
doubtful even to experienced observers ; this may be true
when they are observed through any but an exceptional
atmosphere — and the atmosphere of Flagstaff is one of
the exceptions. There, even under ordinary conditions,
at the proper Martian season most of them are so easily
and certainly seen that there is no reasonable doubt about
them. Before Mr. Maunder ever disco\ered the psychical
effect, Mr. Lowell was perfectly aware of it himself, and
had studied it experimentally, which experiments he has
continued to the present time, with the result that he
finds a clear line of demarcation between confusion of
real and imaginary up to a certain degree of definite-
ness of the real, and an instant consciousness of the dif-
ference between the two above that limit. The brain is
not only conscious of the image, but directly conscious
of reality as opposed to illusion. If Mr. Maunder's
drawings had contained some canals for comparison
with the imaginary lines, this difterence would probably
have been apparent.

The beha\iour of the canals, their waxing and waning
with the advance of the Martian seasons, is proof positive
that they are not due to the integration by eye of perma-
nent faint markings, and it is more difficult to account for
the gradual and regular advance and retreat of such
markings along the line of a canal than for the growth
and decadence of the canal itself. Mr. Maunder's ex-
planation seems to substitute an uncertain and almost
impossible phenomenon for a very certain and probable
one._ From 8,500 determinations of the canals, Mr.
Lowell has recently shown that they come into sight
after the melting of the polar cap in times that are
directly proportional to their distances from that cap
measured in latitude. The enormous improbability of
any such agreement in 375 drawings, the number he
used, is so great as to run into the millions to one.

The logical conclusion of Mr. Maunder's argument, if
valid, is that no faith is to be put in the reality of things
seen, if anybody has e\ er been deceived in the appearance
of such things. The scientific \-alue of facts would then
be liable to complete emasculation by the ignorance
carelessness, or male\olence of an observer. It is time
an end should be put to the inquisitorial fashion of re-
fusing credence to scientific discoveries until they shall
have received the official recognition of the self-constituted
authorities, especially when those authorities do not
represent experts in the subject in (juestion. That it is
useless to continue the observation of planetary detail,

because henceforth no reliance can be placed on what
observers may tell us they have seen of such, can only be
the doctrine of what may be called an " impressionist "
school of science. If Mr. Maunder claims that his ex-
planation is simply one mode of accounting for the
appearance of the canals, he is practically throwing
doubt upon their existence without taking the responsi-
bility for it.

In the course of the discussion of Mr. ]\Iaunder's com-
munication, Professor Newcomb said : " We all know
how one improves by practice, and I think there is such
a thing as improvement of the art of seeing things dif-
ferent from what they really are." This is a gratuitous
slur upon scientific obser\ation, to be justified only by
the heat of a violent quarrel, and inexplicable under the
present circumstances. Surely, Professor Newcomb
cannot believe that the statements of an observer are
any the less credible because he has had experience ?
No ; these experiments show conclusively that observers
must be trained to their work, that even descriptions of
phenomena are of little value unless made by those who
are experienced in observing phenomena of the kind de-
scribed. The reports of such observers must be accepted
as truly indicative of fact until they shall have been
proved to be false, which can be done only by direct
appeal to observation. Williaii Edward Story.

Worcester, Mass., U.S.A., January 2, 1904.
[Mr. Story criticises the paper communicated by Mr. Evans and
myself to the R AS. without first having done us the honour
of reading it. This method has some disadvantages; one being
that many of Mr, Story's remarlis have no bearing at all on the
questions with which we actually dealt. Want of space pre-
vents my dealing with the details of Mr. Story's paper in the
present number of "Knowledge," but if the subject suffi-
ciently interests its readers I may return to it on a later occasion.
For the present, it is sufficient to enter a strong protest against
Mr. Story's quite uncalled-for attack upon Professor Newcomb.
— E. Walter Malnder.]

The Obelisk of Mo\ii\t
Pelee.

Wb. reproduce herewith a remarkable photograph taken
by Mr. E. O. Hovey, for which we are indebted to our
contemporary, the Scientific American. It represents one
of the most peculiar and interesting phenomena of the
recent eruptions of Mount Pelee. This was the growth
of the tooth-like column of rock which arose out of the
centre of the crater. It was first observed (by Professor
Lacroix) in October, 1902, amid the dense smoke and
steam overhanging the mountain. It was then estimated
to be about 295 feet above the rim of the old crater. Put
subsequent observations proved it to be steadily growing,
and after some months had attained a height of over
1000 feet. Professor Heilprin noted a growth of about
20 feet in four days.

\'arious explosions and movements of the earth altered
the relative height of the obelisk. It rose and fell and
large portions became detached. Bit by bit it then
receded again, sinking as much as 150 feet during one
night, but frequently rising again temporarily. This
continued during many months, till finally it disappeared
within the cone.

The cause of this curious apparition can but be vaguely
surmised. It has been suggested that the vent of the
volcano in olden days had become filled with solidified
lava, and when the first outbreak occurred this whole
mass was raised bodily up, as a cork is forced upward
from a bottle.

■ K'iowie.l;f .'- S. iV itr/i.- .Vft,s."

The Obelisk of Morvt Pelee.

Mar., 1904.]

KNOWLEDGE cS: SCIENTIFIC NEWS.

The Face of the Sky for
MarcK.

By \\. Shackleton, F.K.A.S.

The Si'N. — On the ist the Sun rises at 6.4S, and sets
at 5.3S: on the 31st he rises at 5.4.1, and sets at 6.2q.

The vernal equinox occurs on the 21st, when the Sun
enters the Sign of Aries at i a.m. and Spring commences.

Sunspots may frequently be observed, and for plotting
their posiiions the following table may be used.

Date.

Mar. I

.. II
.. 21
.. 31

Axis inclined to \V. from
N. point.

21'' 48'

24^ o'

25° 31'
26" 21'

Centre of disc, S of
Sun's equator.

7' 14'
7" 12'
f>' 57'
6 30'

Date.

Phases.

Mar 2 ..
.. 0 ■•
.. 17 ••
., 24 ..
.. 31 ••

Full Moon
I^si Qnarier
New .Moon
First Quarter
Full Moon

II. M.

2 48 a.m.

I r am

5 39 am

9 37P-m-

o 44 p.m.

The Zodiacal light should be looked for in the west for
a few hours after sunset.
The Moo.v : —

The Moon is in perigee on the 1st and 29th and in
apogee on the 14111.

Occulta-tions.

The following 'are the more interesting occultations
\-isible at Greenwich during convenient hours ; it will be
seen that on the 22nd the Moon is in the Hyades : —

Saturn is a morning star rising a little more than ,in
hour before the sun.

Uranus rises after midnight and is situated rather low
down in the sky near the star 4 Sagittarii.

Neptune, as will he seen on reference to the chart in the
January number, is about midway and 10' south of the
line joining the stars v and u Geminorum.

Telescopic Objects: —

Double Stars. — y Leonis, X.'' 14'", N. 20' 22', mags. 2,
4; separation 3"-8. In stead\'air, the prime reciuisite for
double star observations, tliis double inav he well feen in
a 3-in. telescope with an eyepiece magnifying about 30 to
the inch of aperture, hut on most nights one with a
power of 40 is better.

The brighter component is of a bright orange tint,
whilst the fainter is more yellow.

1 Leonis, XI.'' 19'", N. 115', mags. 4^, 7A ; separa-
tion 2"-2. A pretty double of different coloured stars
the brighter being yellow, the other blue. This object
requires a favourable night and a fairly high power on
small telescopes.

a Leonis {I\ff;iiliis) has a small attem'ant about i ScV
distant, and of the >^'5 magnitude, and easily seen in a
3-inch telescope.

u. Canum X'enat. (Co;- Cai'oli), XII.'' 52", N. 38' 50',
mags. 2-5, 6-5, separation 20" ; easy double, can be seen
with moderately low powers, even in 2-in. telescopes.

Meteor Showers : — •

Radiant.

Date.

R.A.

'Dec.

Near to.

T Leonis
f( Draconis
ii Ursae
f Draconis

Characteristics.

Mar. 1-4
„ 14
.. 24
., 28-

h m.

II 4
16 40

16 44

17 32

4- 4
4- 54
+ 58^'
4- 62°

Slow; bright.
Swift.
Swift.
Rather swift.

The Stars. — About the middle of the month at 9 p.m.
the positions of the principal constellations are as follows :

Disappearance.

Reappearance.

Date.

Star's
Name.

Magni-
tude.

.Vngle from .^ngle from

Mean Time. Mean Time.

\. point \'ertex N. point Vertex

March

22 .

23 ■

e' Tauri
75 Tauri
D.M. 4-
B.A.C. 1391
1 1 T Tauri . .

fi33

10.41 p.m.
10,35 P "1-
II. I p m.
11.39 p.m.
I ! . I p.m.
10. II p m.

223

324'
270

274
293

272"

184°
28.5
232
238

252''
236

Moon's
Age.

\(<
If)
ifi

17
16

The Planets. — ^lercury is in superior conjunction
with the Sun on the 26th, and throughout the month is
too near the Sun for observation.

Venus is an inconspicucus morning star during the
month ; also, as she only precedes sunrise by about an
hour, she is badly placed for observation, and is becom-
ing more unfavourably situated as she is approaching
conjunction with the Sun.

Mars sets about 2 hours after the Sun on the ist,
and about i^ hours on the 31st ; on account of his small
angular diameter, he is an insignificant object in the
western sky shortly after sunset.

Jupiter is in conjunction with the Sun on the 27th,
and therefore is only visible during the early part of the
month after sunset.

Ze.mth . No bright constellations in the zenith.

South . Cancer and Hydra on the meridian ;
Gemini high up, Procyon and Siriiis, all a litlle to
the \y. Orion is to the S.W., and Leo (AVi';////s)
to the S.E. high-up.

West . Taurus, Aries near setting, Auriga
{CapcUa) high up. To the N.W. Perseus, also
Andromeda low down.

East . N'irgo (Spied rising), Bootes (Anttirus).

To the N.L. I'rsa .Major liigh up, (^orcjna, Her-
cules, and Vega low down.

North . /Wfov's ; to the right, Ursa Minor, Draco;
below, Cygnus, Cepheus ; to the left, Cassiopeia.

Minima of Algol inay be observed on the i'')th at
o h. 7 m. a.m., i8th at 8.56 p.m., and 21st at 5.45 p.m.

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

A Photographic Atlas
of the Moorv.

VoLiMi; LI. of the Annals of the Harvard College Observa-
tory is devoted to a photographic atlas of the Moon. This
marks an epoch in selenography, not only because it is the
first complete photographic atlas of the Moon yet pulilished,
but because every part of the Moon is represented under five
different conditions of illumination — sunrise, morning, noon,
evening, and sunset. This fivefold presentation is of the
greatest importance to the selenographical observer, as the
change in appearance of most of the lunar formations during
the course of the lunar day is so great that a photograph
taken at one time becomes almost unrecognisable if compared
with the Moon at another. It constitutes a record in another
particular, namely, that the entire series of photographs were
taken within the short period of seven months. Yet a third
feature of the atlas lies in that this was the first time that a
long focus telescope has been successfully employed in this
department of astronomy. Such telescopes ha\e been em-
ployed with success upon the corona in recent eclipses, but
their application to the systematic record of the Moon was a
new departure.

This work is the result of one of those enterprises which the
measureless energy of Prof. E. C. Pickering, and the corre-
sponding munificence of the American public, have brought
to completion within the last few years. An expedition under
Prof. \V. H. Pickering, who has had much experience of the
superb observing conditions both of .-Xrequipa and Arizona,
was sent out from Har\ard College to the Island of Jamaica,
and reported so satisfactorily on the " seeing," that at the end
of 1900 he took out there a photographic O.G. of i^-inches
aperture, and 135 ft. 4 in. focal length. This was set up at
Mandeville, 20M0 feet abo\e the sea level, and used as a fixed
telescope in conjunction with a heliostat. The seeing did not
prove to be quite equal to expectation, and a yet more serious
drawback was experienced in the want of flatness of the
heliostat mirror. In most cases, therefore, the aperture of the
photographic telescope had to be diminished to 6 inches, and
the exposures lengthened accordingly.

From the photographs taken by the expedition, 80 were
selected, each y in., by 4 in., to form the complete lunar atlas,
the Moon being divided for the purpose into sixteen different
regions, each shown, as noted above, under fi\e different con-
ditions of illumination. The parallels and meridians were
laid down on a photograph of the full Moon, taken on 1901,
August 21), the positions derived by Franz from measures of
five negatives of the full Moon take'n at the Lick Observatory
being taken as standards. Professor Franz's positions are
undoul)tedly the most accurate yet published, and Professor
Pickering devotes the last chapter of his book to an inquiry
as to whether the altitude of a lunar mountain can be deduced
from the discordances between its apparent co-ordinates on
the lunar surface, as measured under different conditions of
libration. The result, howe\er, is not very encouraging, the
displacement to be measured being very nearly of the same
order as the errors of observation, as Mr. S. A. Saunder has
recently pointed out," and a far more extensive series of
me.isures than any yet published are required in order to
satisfactorily solve the question of lunar altitudes. The third
chapter is devoted to the consideration of lunar change ; the
cases of Eratosthenes, Pliniiis, and Pallas being lightly alhided
to, whilst Linne, Plato, and Messier, with its companion
Messier A. are treated with considerable detail. The enlarge-
ments of Plato and Messier, especially the former, by no means
justify Professor Pickering's claim that " these are the first
photographs published, so far as I am aware, showing the details
of the floor so plainly th.it they may l>e clearly distinguished."
They are certainly not equal to the photographs of Plato
in MM. Loewy and Puiseux's .Atlas. Another point on which
Professor Pickering lays himself open to some criticism is the
uncompromising way in which he habitually speaks of bright
spots on the Moon being "snow," or "hoar frost," or " ice "

• Observatory, iyo.|, Fobni.iry, p. y6.

whilst dark spots are often as unhesitatingly described as
■• patches of vegetation." While not wishing to ignore the
very considerable amount of evidence which Professor
Pickering has elsewhere presented in favour of these, his
views, they cannot yet be regarded as more than mere opinions,
and it is hardly legitimate for him to express himself as if they
were altogether beyond challenge.

" Ann.'ils of the Astronomical Observatory of Harvard College,"
Vol. LL, a Photogr.iphic Atlas of the Moon, by William H. Pickering,
Cambridge, Mass. Published by the Observatory, 1903.

La>.rge v. Small Telescopes on
Planets.

To THK Editors ok " Knowledge."

Sirs. — I was much interested in Mr. A. Stanley Williams's
letter in the current number of " Knowledge." No doubt
there is reason in his suggestion. But to my mind there is a
much stronger reason for the greater relative defining power
of small telescopes when used on planets over their perform-
ance on double stars, which seems to be generally overlooked.

( )n double stars, I Iielieve. the rule of 4-56 seconds of arc
divided by the aperture is generally accepted as the limit of
the telescope's di\'iding power, and this agrees very well with
theory. But it only holds good when the objects to be sepa-
rated are sufiiciently bright to cause strong interference
effects. Now the details on a planet are seen against a back-
ground nearly as bright, and except at the edges the contrast
is ^•ery feeble, so interference phenomena .are less appreciable.
Therefore I hold that the 4-56 seconds-over-aperture rule does
not apply. Mr. .\. Stanley Williams, in his first paragraph,
also seems to imply a doubt of ordinary rules holding for lari^c
areas, but I maintain that small telescopes will separate details
on a planet very much closer than the above rule would
allow. And so would, and sometimes does, a comparatively
large aperture, but the magnification needed to tone down the
light to utilize the larger aperture needs better atmospheric
conditions, so that it is comparatively rarely that such aper-
tures can be used with full effect. If we take 40 diameters to
the inch of aperture as about the best ratio for viewing, say.
Mars, one will on most nights find the seeing good enough to
use the 120 needed by a 3-inch. But apply that rule to the
40-inch Verkes, and how often can a power of 1600 be
employed to advantage ?

A few years ago I made some experiments to test the sepa-
rating power of I inch of aperture directed to black spots on
white paper. I found that i inch would divide dots separated
not more than i second of arc. and lines 07 second apart ;
and that it would show a single black line o'S second in
width, which was, of course, separating white areas divided
by that amount only. I think these experiments, which
can readily be repeated by anyone who wishes, show
that when interference effects are negligible, one may expect
a telescope to go far beyond the usually accepted limits. But
if more were needed, Mr. and Mrs. Maunder have supplied it
in the paper published last July in the B.A.-A. Journal
alluded to by Mr. Williams in his letter to " Knowledge."
There they show that a black line on unglazcd paper was seen
sharply defined with the unaided eye under an angle of only
2'S seconds of arc. Taking the pupil of the eye when fully
dilated at the extreme of one quarter of an inch, this is
equivalent to 07 second of arc for i inch, which agrees well
with my own experiments detailed above, though I consider
it much more noteworthy, as the retina is composed of hexa-
gons that at the nodal point of the lens system 01 the eye
subtend an angle of about 23 seconds of arc, and th.at such a
coarse structure should show a line only 2'8 seconds wide as
sharply defined seems to bear out what Mr. Maunder says in
his last paragraph, that : " A straight line is that which gives
the least total excitement in order to produce an appreciable
impression, and therefore the smallest appreciable impression
oroduces the eff'ect of a straight line."

H. W.\KE.

Whiteha\en, January 11, 1904.

Mar., 1904.]

KNOWLEDGE & SCIEXTIEIC NEWS.

ASTRONOMICAL.

Mr. Denning's Observa.tions of Mars
in 1903.

In the Astroiu'iiiisilw S'liiliiichten, No. 3426, Mr. F. W. Demiiiig
gives the main results of his observation of Mars with a lo-inch
reflector, in the Spring of 1903. The powers that he used
ranged from 252 to 4S8. but the one most commonly employed
was 312. He noted that occasionally there were decided
changes in the visible appearance of certain markings, and
these changes were obviously not due, either to uncertain
seeing, or to the varying inclination of Mars, but, in the
observer's opinion, to local vagaries in the Martian atmosphere.
Thus, on May 6 and 7, he saw a white band dividing the canal
Nilus, not seen on March 31 or April 2, and not shown on the
charts, .\gain, on May 21. the northern region of the Syrtis
Major was very dark, with a white cloud on its southern edge,
but on May 23 and 24 the whole Syrtis Major was very faint,
as if veiled by the cloud spreading northwards. As regards
the " canals," Mr. Denning says : " ,\ large number of
irregular dusky streaks ^canals), different in tone and direction,
were observed. Some of these were very distinct, as, for
example, Nilosyrtis, Protonilus, Indus, Ganges. Cerberus,
Casius, &c., while others, as Phison, Euphrates, Gehon, were
feeble or extremely faint and delicate. Many of them were
knotted or strongly condensed in places, and particularly so at
those points where either a junction or intersection of two of
them occurred." Mr. Denning considers these streaks as
certainly objective. He says that they were single, though in
a few instances two of them w-ere placed tolerably near to-
gether, running in appro.ximately parallel directions. He is
emphatic that the " prolific system of double canals delineated
by some observers had no existence " during the period of
observation, as far as his eye and telescope could determine.
Comparing these recent observations with those made in
February, i.S6g, Mr. Denning deduces from I2,ij6 rotations of
Mars, the value 24 h. 37 m. 22-7 s. for the rotation period.

The Double Carvals of Ma.rs.

Mr. Lowell, in Bulletin No. 5 of bis Observatory, gives
evidence against the hypothesis that the gemination of the
Martian canals is an interference effect. If it were so, the
width between the two components of a double canal should
vary inversely as the aperture. To test this, Mr, Lowell ob-
served a number of double canals with the full aperture of his
telescope ^24 inches), and then with that aperture reduced to
18, 12, and 6 inches. His measures of the drawings made
under these several conditions showed that the apparent
angular separation did not increase as the aperture was
diminished ; that the separation was invariable within the
limits of observation for any particular canal, but differed for
different canals, bearing no relation to the width of an inter-
ference pair of lines.

Mr. Lowell's ObservaLtions of Ven\js
in 1903.

In Bulletin No. 6, Mr. Lowell classes the markings to
be made out upon Venus under two heads. The first includes
the collar round the south pole and the two spots on it, and
the nicks inward from the terminator. Of these Mr. Lowell
states he has ahvaysbeen certain, and "they alone are sufficient
to show that the planet's rotation is an affair of about 225
days." The second class include the long shadings from the
centre of the disc to the terminator, and of these, also, Mr.
Lowell asserts " the objectiveness beyond the possibility of
illusion." It will be seen that in this assertion Mr. Lowell is
withdrawing his withdrawal of these markings which he pub-

lished some eighteen months ago in tlir Aslivnoniisclti'
Xiichrichltii. No. 3.S23. Mr. Liiwell furtluT adds that these
streaks "bear no resemblance whatever to the ' canals '. of
Mars, They are faint streaks or spots. . . . Tlu-v .ire not
of even width, are not dark, and shai^iicul,^ .^ , . I'urllier-

more, they are of a much higher order ortlill^iMtv c;l'vul(i»jj,s
the conditions of visibilitv arc such as to sliilWajo ohsersi-r iTuT

'canals' of Mars with ease,

^i.^o saowajo^kse .
aiuty, it wcreliSfTess to

attempt this much harder plaiic*'.* Vjl-!ijt'il6^i^|}37s,WW' Lowuli
Bulletin ch- la Socictc'^:\str,mnn,,,,ur^}»l l-i>mflU:

etle^

wrote in the

" Lcs configurations out tonjours dJiHrt ■^
en veritc que celles de la Lune. ' In
for December, 1S96, lie wrote ; " The markiii,L;r. .nr iHuiniisi
and well defined ; their contours standing out sharply against
the lighter parts of the disc. . . . The seeing must l)e dis-
tinctly bad to have the more prominent among them not discer-
nible." This would seem to show that the definition at Flagstaff.
Arizona, has changed seriously for tiie worse in the last seven
years, whilst a comparison of the drawings of Venus, given in
ttie Bulletin, with those of M.ars, such as in I'opitli::-
.Istroitiiiny for y\pril. iiS()5, would not lead to the conclusion
that there was any essential difference lietwcen tlie streaks on
the two planets.

Calcium and Hydrogen Floccxili.

A memoir of quite exceptional interest is given on the
subject by Professor G. F. Hale and Mr. Ellerman in Volum.
III., Part I., of the Puhlutilioiis vf the Yirkcs Observatory
Its subject is the minuter study of the surface of the sun by
means of the spectroheliograph. The first point brought out
is the essentially granular structure of the calcium fiocculi,
the entire surface of the sun showing a fine mottling when
photographed on the l)right K-hne, The next point is the
study of these calcium clouds at difi'i-rent levels, the result of
the examination bringing out in a striking manner the way in
which the calcium bright clouds expand as they rise higher.
The detection of the dark hydrogen fiocculi is another feature,
and the fact that they often correspond, though not precisely,
with the bright calcium fiocculi. Last of all the discovery of
dark calcium fiocculi was established, and the necessity for
further work with spectroheliographs of much higher disper-
sion, and working upon larger images of the sun, is insisted
upon. The memoir is illustrated by fifteen extremely fine
photographic plates.

The Nebulae.

The Siiictccnth Century (iiui After for I'ebruar}' contains
an article on " The Nel)ul;c," l>y the Rc\'. ICdnumd Ledger
(iresham Lecturer on Astronomy, whicli summarises with
admirafjle clearness and precision, the state of our present
knowledge respecting these mysterious objects, and the con-
nection with them of the stars.

ZOOLOGICAL.

At the meeting of the Geological .Society lield on January 20
Dr. A. Smith Woodward, of the British Museum, definitely
determined th(^ .systematic position of the cretaceous fishes of
the genus I'tycliudus, whose large, quadrangular, ridged crush-
ing teeth are such familiar objects to collectors in the chalk-
pits of the south-east of England. It has long been known
that I'lychudus was an elasmobranch fish, and Dr. Woodward
himself had some years ago pointed out the probability of its
being a ray, or skate, rather than a shark. The truth of this
conclusion is fully demonstrated by a specimen of the jaw
cartilages recently discovered near Lewes, which serve to show
that these fishes were allied to both the eagle-rays and the
sting-rays, and probably, therefore, the ancestral type of bolli.
A photograph was shown at the meeting of a splendid .\mcri-
can specimen of the dentition of Ptychudus, witfi the teeth in
their natural position, forming longitudinal rows.

* ;;■-

Fossil Birds-
Certain fossil bird reiriains were discussed by Dr. C. W.
.Andrews at the meeting of the Zoological Society held on

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

January ly. From Madagascar the speaker described a pelvis
and thigh-hone of an ostrich-lil<e bird closely allied to the ex-
tinct roc LJipyoniis) of that island, but regarded as generically
distinct, under the name of Mullcyoritis.. Much greater interest
attached to a fragment of another bird of the same group from
the Eocene strata of the Fayum district of Egypt, for which
the name F.nmuiiiis was suggested. Possibly the discovery of
this specimen might serve to demonstrate that all the ratitc
birds ha\e a common ancestry, and are not. as some suppose,
isol.ited members of a number of distinct groups which have
lost the power of flight independently of one another.

A Sub Species of Gira.ffe.

M the meeting of the abo\ e-named Society, on February 2,
the local sub-species of girafl'e formed the subject of a com-
numication by Mr. Lydekker. It was shown that, as in the
case of the boute-quagga, or BurchoU's ;;ebra, a number of
local forms readily distinguishable by their colour and mark-
ings, and (in the case of the giraffe) to some extent also by
difterences in the skull, are recognisable as we proceed from
north to south down the eastern side of the Continent. In
both instances it seems advisable to regard their local forms
as races, or sub-species, rather than species. The northern
tonus are characterised by the presence of a large frontal horn
and the white legs; but, as we proceed south, the median
horn gradually becomes reduced to a mere boss, while the
legs aci|nire spots right down to the hoofs. In the latter
respect giraffes show a modification, exactly the opposite of
that presented by the boute-quaggas, in which the legs lose
their stripes as we proceed south. Some of the East African
giraffes are very remarkable, developing, in certain instances,
rudimentary horns on the occiput, or o\er one eye, or dis-
playing a marked sexual difference in colour. A race from
the south of Lada was named in honour of Major Powell-
Cotton, the celebrated explorer, and a second, from the
Northern Tranb\aal, after Mr. Rowland Ward, of Piccadilly.

Ca.chalot Whales.

In the I'lilil of January j reference is made to the occurrence
ol (juite a number of sperm-whales, or cachalots, in the North
Sea and North Atlantic ; no less than se\en adult bulls lieing
definitely known to have been captured. As a rule, these
whales are confined to tropical and subtropical seas, only a
few old bulls occasionally straggling northwards. In the pre-
sent instance a whole herd must have thus wandered out of
the proper latitude. Recently Sir William Turner has re-
corded the capture of an old bull in the Shetlands in igoi,
also mentioning that a herd was seen off the Faroes in iSyy;
while in the Field of January jO Mr. T. Southwell refers to
accounts of herds of these whales straying northwards in 1723
and 1752-53.

The Primeval Instincts.

A discussion has been going on in the columns of the Field as
to the reason why horses when getting up from the recumbent
posture raise themsehes first on the fore-limbs while ruminants
do so on the hind-limbs. It appears that tapirs, apparently
rhinoceroses, and swine follow the horse-fashion ; an associa-
tion which demonstrates that the movement is not dependent
on the presence of a third trochanter on the fenmr of the
Perissodactyla (hor.ses, tapirs, and rhinoceroses). One writer
has suggested that the ruminants' mode of rising is for the pur-
pose of bringing the horns into action for defence as soon as
possible, but against this is the case of the rhinoceroses.
I'ossil;ly the raising of the hind-legs first may be connected
with the function of rumination and the complex form of
stomach correlated therewith. One correspondent stated,
however, that an ass rises like a ruminant, which, if true, upsets
all theories.

New Ma.mmals.

An instance of the pace .it which .Vmerican naturalists are
increasing zoological nomenclature is atlorded bv a paper by
Dr. 1). G. Elliot recently published by the Field Columbian
Museum of Chicago, in which no less than twenty-seven ap-
parently new forms of manunals arc described. Hitherto
there has been supposed to be only a single species of glutton,
ur wolverine, but tlie author describes the .\laskan represen-

tative of that animal as new, under the name of i;ulo lutcus.
A new race of bighorn sheep {Ovis caiunlcnsis cremnobates) is
also recorded from the San Pedro Martir Mountains of Lower
California and Mexico.

Bird Migration.

Mr. W. Eagle Clarke, who is well known as an authority on
the subject of the migration of birds, made a month's stay last
autunm on the Kentish Knock Lightship, and the results of
his \aluable observations are detailed by him in the Ihit,. It
recpiired a good deal of courage to brave the hardships and
discomforts inseparable with life on a lightship 21 miles from
the nearest point of land, but Mr. Clarke was so engrossed
with watching the birds which passed the ship by day and
were lured to its light by night that he seems to have hardly
noticed the discomforts involved, .'\part from the valuable
details regarding the various species of birds migrating and
the directions in which they were travelling, as well as many
other points which we have not space here to discuss, Mr.
Clarke makes some remarks of high importance with regard
to some of the phenomena of general interest connected with
bird migration. As an explanation of how birds find their way
during migration it has been suggested that the great height
at which they fiy enables them to see enormous distances.
But Mr. Clarke, while not denying that birds sometimes do
migrate at great elevations, disposes of the theory that they
depend on this means for finding their way. During all the
time he was on the Kentish Knock Lightshii) the migrants of
every species flew close to the water. Vet whatever the
weather or state of the sea they kept a straight and apparently
unerring course for the coast 21 miles distant. Mr. Clarke
reaches the conclusion from this and other facts that liirds are
endowed with a sense of direction. Such a statement is, of
course, in no way an explanation of the mystery as to how
birds find their way, since we have no conception of the
nature or workings of such a "sense." But the evidence that
they do not find their way by sight is of the utmost import-
ance. Those interested in bird-migration should not fail to
read Mr. Clarke's latest and very valuable contribution to our
knowledge of the subject.

Burrowing Fishes.

In h'lihiiiitli MiiLiwnsis.a. publication devoted to the descrip-
tion of the results of a recent expedition to the Malay Penin-
sula, a writer records a remarkable habit on a part of one
species of the nuid-haunting fishes of the genus Pcriophthalmui.
These fishes make burrows in the nmd, and retain a pool
above the same, by preventing the water from flowing away
during low fide by means of a circular well built by them-
selves.

One of the most remarkable paheontological discoveries is
recorded from North .America, where an Eocene lemur is
believed to be allied to the curious aye-aye iChii'omys) of
Madagascar. The extinct form is named Parihtiiroinys.

Papers Rea.d.

In addition to those already mentioned in special para-
graphs, reference may be made to the following zoological
papers read at various scientific societies. .At the Linntean
on December 17, Mr. H. J. Fleure discussed the origin and
evolution of the gastropod molluscs known as Ducogloisa, of
which the limpet is a famiUar example. At the same Society
on Jamiary 21, the Rev. T. R. R. Stebbing read a paper on
the Crustacea obtained during surface dredgitig from H.M.S.
lifsearcli, in the Bay of Biscay, during the sunnner of ii)00.
On January ly, before the Zoological Society, Mr. O. Thomas
described a new subspecies of the aoul(<;((;i7/((ii(i-»;H;t' /•/»!,';) from
North-East Africa. At the same time Mr. G. A. K. Marshall
presented a monograph of the beetles of the genus IlippurliiHUi.
Dr. W. Kidd called attention to the importance of the arrange-
ment of the hair and the distribution of hair whorls in the
classification of mammals. Dr. W. G. Kidewood described
the skull of the giraffe, as seen in vertical transverse sections ;
and Mr. F. E. Beddard read a note on the brain of two lemurs.
At the meeting of the same Society on February 2, in addition
to Mr. Lydekker's paper on girartes, a communication was
received from Mr. tX Thomas on a collection of mammals
from .Namaqualand, including a new species of strand-mole

Mar,, 1904.]

KX0\\L1:DGK c^ SCIl'NTIFIC NEWS.

{Baihi/irgiis); and Mr. Bedd.ird discoursed on the arteries of
the base of the brain in certain nuunnials. Two papers by
Mr. G. .A. Boulen,t;er were also taken at the same nieetinf;, the
one dealing with throe new fishes from the Niger, and the
other with the type L-pecimen of the West African catfish
known as Clariiis /<i;'iiv/is. Ai the meeting of the same
Society, held on February 16, Mr. C. Crossland presented the
third instalment of a dissertation on the marine fauna of
Zanzibar and British ICast .Vfrica, dealing in this instance
with the polychietous annelids : and also a second paper
describing a collection of the same group of organisms from
the Mahay Peninsula. The third paper, by Sir C. l-.liot, dealt
with certain nudibranchiate molluscs from '/Cannhav and
British East Africa.

A New GaLzelle from the White Nile.

Considerable iiUerest attaches to the description by the
Hon. Walter Kothschild, in .W; iVii/tv /<i(ilof;iCiC, of a fine new
species of gazelle from the banks of the White Nile, which it is
proposed to call Giiztllii alhoiiotalti.

BOTANICAL.

HhKK LiNUEMi Til, of Bcrliii, has published in Cirtaitiora,
1903, Heft iS and 23, the results of his experiments on the
propagation of plants by means of their leaves. Horticul-
turists have long been accustomed to use this means of pro-
pagation in a few plants, notably in the Gluxinia and certain
Crassulaces, among which Bryuphylluin calycinuin is a well-
known example. It was, however, probably not suspected
that the leaves of so many plants could be made to produce
roots. In his first communication Herr Lindemuth gives the
names of twenty-eight species, of nearl)' as many different
genera, in which his experiments have been successful. These
include such plants as the Foxglove {Digitalis purpurea), the
Musk [Miinulus moschatus), the Tomato, and the Vine. The
leaves of thirteen species, including the Potato, Monkshood
(Aconilum Xapcllus), and the common bedding Geranium
{Pelargonium zoitaU) refused to root at all. Usually the roots
were produced quickly — in the Vine in sixteen days, in
Veronica in seven days, and in the African Marigold in eight
days — but the amount of time required, and, indeed, success
at all, was shown to depend very much on the season when
the experiments were made. Thus, in the Vine, roots were
developed in sixteen days in .August ; but complete failure
resulted in September, when the leaves perished. In his
second communication, the author records success with thirty-
four additional species, including three of those with which he
had met with failure before. The results so far obtained shovv
that few of the leaves thus experimented on will form buds,
only five having done so. In the case of a species of Citrus,
the leaves rooted and persisted for months and even years
without any further development. — S. A. S.

Recent Research in Agricuhure-

Mr. Hall, the Director of the Rothamsted i:xperimcntal
Farm, lecturing at the Royal Institution on " Recent Research
in Agriculture," dealt with the growth of wheat, still an impor-
tant crop in Great Britain, despite the fact that the area under
wheat has shrunk from more than four million acres in i860
to less than i,.Soo,ooo at the present time, and that we only
now produced about seven million quarters, and had to im-
port more than 25 million (luarters. The English yield
averaged, however, more than ji bushels per acre, consider-
ably greater than that of any other country, and double or
treble that of the chief countries who send us wheat. The
lecturer then showed, by examples drawn from the Rotham-
sted experiments, that the production of wheat could be
greatly raised by the use of manures, but that this process
soon ceased to be profitable—"' high farming is no cure for low
prices." A further difficulty to be faced by the English wheat
grower is the comparatively low price of this product, the best
Manitoba or Russian or Argentine wheat realising 20 to 25 per

cent, more than the best English wheat. This dillereiicc of
price is due to the greater '• strength " of the flour made from
such foreign wheats, meaning by " strength " the capacity to
make more and larger loaves for equal weights of lloiir used.
The lecturer illustrated tlie point by exhibiting loaves baked
from eijual weights of luiglish and .American llour, the
.\niorican one being decidedly larger ;iiid more attractive in
appearance. For some time the lecturer had been concerned
with ;in en(|uiry initiated by the National .Association ol
Millers, and helped by the Board of .\griciilture, as to the con-
ditions which brought about " strength " in flour, and how
ICnglish wheat could be impro\ed in this respect. Climate
being one of the chief factors, the lecturer contrasted the
ICnglish climate with thai of the Hungarian Plain and of the
North West. The development of wheat, the r.ite of forma-
tion of the grain, and the migration of the nitrogenous con-
stituents into the grain was then studied at Rothamsted, and
compared with similar results obtained in Hungary ; all tend-
ing to show that strength is associated with a short period of
ripening. Strength is dependent on the nitrogenous content ol
the wheat, but the attempts to correlate it more exactly with
total nitrogen, with gluten, or with the ratio between gli.adin
.uid glutenin, as certain French and .American chemists have
done, fail to show consistent results. Climate is not, however,
everything in causing strength, for even among b^nglish
wheats some are much strongc'r tlian others. Certain
foreign varieties also when introduced into this country retain
to a very considerable degree their strength, at any rate for
three or four years. However, they generally give crops con-
siderably below the English stand.ird, though for late spring
sowing some of the best, like No. i Hard Manitoba, .are prob-
ably ecjual to .any lingllsh varieties. As "strength" is a
(|uality inherent in the variety, it is capable of improvement
by cross-breeding .and selection, and a considerable amount of
% ery promising work has idready been done in this direction,
the disideralum being increased strength with the cropping
powers of the best I-Inglish varieties. The lecturer exhibited
various loaves made from English and foreign varieties of
wheat grown in this country to illustrate the foregoing points.

PHYSICAL.

Photography in Natura.! Colours.

Thl principal novelty of a process lor obtaining photographs
with natural colours, just brought out in Berlin, is the fact
that any ordinary negative may be made to give chromatic
prints with the original colours. Suppose a view of a lands-
cape to be taken with an ordinary plate; the sky being blue,
will throw on the plate the most efficient light, so as to pro-
duce on the negative the thickest dark layers. The leaves of
the trees, on the other hand, will produce less intense effects,
and still less will be the action of the red portions. Now the
in\ entor, Oberleutnant von Slawik, .an .Austrian, has designed
a special kind of pigment paper, bearing a nuinber of super-
posed dye-stull layers ; underneath there is a red layer, in the
middle a green, and above a blue layer. Now the most
strongly C(jvercd portions of the negative -representing the
sky — will evidently be the least translucent, the light actually
penetrating being able to act only on the upper blue layer,
rendering insoluble only the chromium jelly constituting this
layer. The thinnest portion of the negative, corresponding
for instance to a red wall, will in printing transmit the
greatest amount of light ; all three pigment layers thus being
struck l)y the light will become insoluble down to the loA-est
red layer. The green leaves will, as above shown, give rise
to a covering of the plate of medium intensity, a medium
amount of light penetrating the paper at the corresponding
portions of the plate, this amount of light being just sufficient
to render insoluble the two upper blue and green strata,
whereas the lowest layer will remain unaltered.

.After printing, the paper, as usual, is pressed on another
sheet of paper, when the coloured layers are transferred from
one sheet to the other, the printing being afterwards "deve-
loped " with warm water, in the way usual in pigment printing

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

After the transferrins the low layers of the original paper
will in the new paper be uppermost. The warm water will,
therefore, be able to rinse off any jelly layers which have
not become insoluble by the effect of light. On the portions
corresponding to the sky, the green and red layers which are
not struck by light will be removed, the blue layer only
remaining. In the red wall, where the light as above shown
has penetrated all the existing layers down to the lowest red
layer, which, after the transferring is above all the remaining,
no alteration will be produced, while in the portions corre-
sponding to the green leaves only the red layer, which
now covers the green colour, will be washed off by
the water, when the green colour becomes visible, covering
the blue layer lying underneath. In practice, it has been
found advisable to use a larger number of coloured
layers instead of those corresponding to the three funda-
mental colours only, so as to produce all the shades required ;
up to 14 pigments are thus used. The abo\e process has
been developed in the laboratory of Dr. Ad. Hesekiel
and Co., Berlin. .As a matter of course, any old negati\-es
taken at any time may be made to reproduce the true colours
of the original. — A. G.

The Blondlot or N-Rays

In view of the interest which has been imparted to M. Blond-
lot's X-rays by the investigations of Professor Charpentier,
and also by the doubts which ha\e been thrown on the real
existence of the rays, we have thought that it might be inter-
esting to collect the ascertained facts and observations con-
cerning these rays. For this summary we are chiefly indebted
to a series of articles contributed 'by Mons. La\ erune to
Casinos.

The X-rays were discovered bv M. Blondlot, of Xancv.
while studying Rontgen rays. By endeavouring to pass rays
through a sheet of aluminium, he separated quite a new group
of radiations. The rays he found were such as to penetrate
alumunum. black paper, or wood. They could be polarised
and might be deflected or diffused, but they produced neither
fluorescence nor photographic action. They were invisible,
gave no sensation of light, but augmented the brilliancy of an
electric spark.

It is this property which enables us to detect the ravs. They
are incapable of exciting phosphorescence in bodies which caii
ac(imre this property from the action of light ; but when such
a body, sulphuret of calcium for instance, has first been ren-
dered phosphorescent by exposure to light, then if submitted
to the action of these rays, especially if they are focussed bv
a quartz lens, one can see the brightness of the phosphor-
escense perceptibly increase. In the same way if one directs
them on to a little flame of gas at the end of a metal tube
pierced by a very minute orifice this flame, entirely blue,
becomes whiter and more luminous. We are now furnished
with these means of detecting the presence of these radiations.
M. Blondlot, struck with certain analogies that they present
with the radiations discovered by Professor Rubens in the
emissions of the Auer Burner, asked himself if the X-rays
were not identical. An Auer burner .was enclosed in a kind
ot Lantern of sheet iron closed at all points, with the exception
ol the openings for the escape of air and the gas from com-
bustion, and so arranged as to prevent the passage of any
light. A rectangular window opened in the iron at the light of
the incandescent mantle was closed bv an aluminium sheet
I mm. in thickness. The chimney of" the Auer burner is of
sheet-iron. A slit was opened opposite the mantle, so that
the luminous rays which emanate from it might be directed
on to the aluminium sheet. Outside the lantern in front of

he alummmm sheet was placed a biconvex lens of quartz, and
behind It an exciter giving little sparks. It was ascertained
that the spark is of greater or less clearness according to
the distance at which it is placed from the slit. M. Blondlot
proved the existence of four distinct kinds of radiations.
\V hen one directs a pencil of these rays either on to an
electric spark, or on to a little flame, or a phosphorescent
•substance previously exposed to light, one can see the li<'ht
emitted by these different sources increase in brilliancy

The greater number of artificial sources of light and heat
emit X-rays. The sun emits them, as the following experi-
ment shows : A completely dark and closed room has a
window exposed to the sun, this window is shut by inside
oak shutters, 15 millimetres in thickness. Behind one of
these shutters, at a distance of i metre, is placed a tube of
fine glass, containing a phosphorescent substance of sulphu-
ret of calcium for example, previously slightly insulated. If
now in the trajectory of the sun's rays, which are supposed to
reach the tube through the wood, there is interposed a piece
of lead, or even simply the hand, even at a considerable
distance from the tube, the brightness of the phospho-
rescence diminishes. If one takes away the obstacle it re-ap-
pears. The interposition between the shutter and the tube
of several sheets of aluminium, of cardboard, of a piece of oak
three centimetres thick, does not prevent the phenomenon
from taking place. All possibility of heat radiation, properly
so called, is therefore excluded from hypothesis.

Certain substances appear to have the power of storing up
X-rays, and afterwards emitting them ; but the rays appear to
penetrate a metallic mass, in this sense, very slowly. Thus,
if one side of a sheet of lead two millimetres thick has been
exposed to X-rays for some minutes, that side only has become
acti\e. An exposure of several hours is necessary for the
activity to reach the other side. .-Muminium wood, dry or
moist paper, paraffin have not the property of storing up
X-rays. Sulphuret of calcium has it. Having enclosed a
dozen grammes of this sulphuret in an envelope, and then
having exposed the envelope to X-rays, M. Blandlot proved
that its neighbourhood sufficed to reinforce the phospho-
rescence of a little lamp of sulphuret previously exposed to
light. This property explains why the increase of the phos-
phorescence of the action of X-rays takes an appreciable
time both to be produced and to disappear. Owing, in fact,
to the storing up of the X-rays, the different portions of a lump
of sulphuret mutually augment their phosphorescence, the
storing up is progressive, the store is not instantly exhausted,
so that when one directs the X-rays on to the phospho-
rescent sulphuret their effect slowly increases, and when they
are suppressed their effect is only gradually extinguished.
Following on the experiments made by M. Charpentier on
the emission of X-rays, experiments to which we shall return,
M. Blondlot conceived the idea that certain bodies might ac-
quire the property of emitting rays from compression. He
proved that pieces of wood, of glass, of indiarubber com-
pressed by means of a carpenter's vice, become, during the
compression sources of X-rays.

Bodies which are themselves in a state of forced equilibrium,
or molecular strain, as tempered steel or hammered brass, are
spontaneous and permanent sources of X-rays. One can show
it by means of tlie phosphorescent screen, and by another in-
direct method — that of the increased action of a pencil of light
upon the eye when it is accompanied by X-rays.

The shutters of the laboratorj- are almost closed, and the
face of the clock fixed to the wall sufficiently lighted for it to
appear faintly as an indeterminate grey stain upon the wall at
a distance of four yards. If the observer, without changing his
place, directs towards his eyes the N-rays emitted by a brick
or pebble, previously insulated, he sees the face whiten, distin-
guishes clearly its circular shape, and may e\en succeed in
seeing the hands. When the X-rays are suppressed the face
again darkens. Xeither the production nor the cessation of
the phenomenon are instantaneous.

.\s in these experiments the luminous object is placed very
far from the .source of the X-rays, and as besides, in order that
the experiment should succeed, it is necessary that the rays
should be directed not towards this object, but towards the
e)-e, it follows that there is no question here of an increase of
the emission from a luminous body under the influence of X-
rays, but rather of the reinforcement of the action received by
the eye, which is due to the X-rays which are joined to the
rays of light. One can replace the brick by a sheet of
tempered steel.

The energy that the emission of X-rays represents is
probably borrowed from the potential energy which corres-
ponds to the forced state of tempered steel. This expenditure
is doubtless extremely feeble, since the effects of the X-rays
themselves are so, and thus explains the apparently illimit-
able duration of the emission. A sheet of iron that is bent
so as to take a permanent deformation emits N-rays, but

Mar., 1904.]

KXOWI.KDGF. .'V SCIENTIFIC NEWS.

the emission ceases at the end of some minutes. A block of
aluminium struck with a hammer does the same, but the
duration of emission is much shorter. In these two cases
the molecular constraint is temporary, and the emission of
N-rays also. Torsion produces analogous results to com-
pression.

Professor .V. Charpentier's investigations of N-rays are
second in importance only to those of their discoverer. He
sought for the radiation of N-rays chiefly with the aid of phos-
phorescent screens of sulphuret of calcinm. but found that
screens coated with platinocyanide of barium, whose fluores-
cent intensity he rejjulated. with the aid of a salt of radium,
covered with black paper, would give more satisfactory results.
By these two processes of research, he discovered that N-rays
can have several other origins than those of the sources of
light indicated by M. Blondlot. He recognised that the little
phosphorescent or fluorescent object increased in luminous
mtensity, when it was brought near the body. Moreover this
augmentation is more considerable in the neighbourhood of a
muscle, and so much the greater as the muscle is strongly
contracted. The same thing occurs in the neighbourhood ot
a nerve, or of a nervous centre, where the effect increases witli
the degree of activity of the nerve or of the nerve centre. By
this means, in spite of the delicacy of the observation, one can
recognise the presence of a superficial nerve, and follow it.
These effects are not only observed by contact with the skin.
they are perceptible at a distance. They are transmitted
through substances transparent to N-rays (aluminium, paper,
glass, &c.), and stopped by the interposition of substances.
which are opaque to the same rays, lead (incompletely) or wet
paper. They are not due to an increase of temperature in
the neighbourhood of the skin, for they continue if several
sheets of aluminium are interposed, or of cardbo.ard separated
by layers of air and forming a calorific screen. These rays
are reflected and refracted like N-rays.

M. Charpentier has produced foci, manifested by the maxima
of brightening by the aid of convergent glass lenses. The
position of these foci, or maxima, although difficult to
exactly determine, permitted recognition of the fact that the
indication of refraction of rays emitted by the body was at
least of the class and size of that determined by M. Blondlot for
N-rays. It might be asked if the human body really emitted
these rays, or if it only stored them up during the day or in
the Ught, in the same way as the insulated bodies studied by M.
Blondlot. After a sojourn of nine hours in complete darkness
the phenomena were the same, and were still more easy of
observation, because of the more perfect adaptation of the
eye. The nerves and nervous centres, when they are the seat of
an excitation, emit the rays in greater abundance. Charpentier
has been able to determine the area of the heart ; he has also
been able to follow the trajectory of a superficial nerve ; he
has been able to recognise the topography by certain psycho-
motor zones in the cerebral surface. He has seen in fact, that
if the subject of the experiment happens to speak, the de-
tective screen, when advanced at the same moment towards
the region of the cranium which corresponds to the zone of
articulate language, at the level of the left frontal convolutions,
is more brightly illumined than when he kept silence. The
researches of Charpentier suggest that the radiations called
N-rays are not all alike, but must in reahty result from an
assemblage of radiations of attributes as diverse as their origin
some being emitted especially by the elements of the nervous
tissues, and others by those of the muscular tissues. This
theory is in accord with the physical observations of M. Bond-
lot. Experiments already dating from several months have in
fact shown to this eminent physician that the bundles of N-
rays broken up by a prism spread themselves into a sort of
spectnim, which establishes beyond proof that all the broken
rays — rays whose wave length, incomparably smaller than
that of light rays — are unequally refrangible, and conse-
quently possess each individual attributes. The wave length
has been recently determined as not greater than S micro-
millimetres — about the one millionth of a centimetre.

We have received from Mr. H. J. (ilaisher a copy of his
March catalogue of ■■ remainders," which we notice contains
many valuable and useful volumes in zoology, botany, and
the various other branches of natural and applied science.

The Super-Solid.

Hints towards a Conception of the
4th Dirrvervsion.

I!y C. E. Bi;nham.
Sp.i^cE, as we conceive it, comprises length, breadtli, and
thickness, and it is hardly possible to imagine a fourth
direction which is none of these. Further than that, our
minds are so constituted that we seem to see that such a
n w direction could not be. When we have traversed
any material substance longitudinally, and across, and up
and dov.n we appear to ha\e traversed it exhaus-
tively. There is no direction which is not one of these -
or, as we might say, there could be no direction which is
not one of these three or intermediate between them.
This is so as to all material substance, and that it is so
as to space in the abstract we feel equally convinced,
because by space we mean nothing else but the length,
breadth, and thickness which matter occupies or might
occupy.

Yet, as everv appreciative reader of Abbott's Flatland
knows, there is more to be said on this matter. Suppose
a race of beings whose senses were such that they had
never had any reason to suspect thickness as a property
of matter, but were only conscious of length and lireadth,
would it not appear to them that length and breadth
filled all space, and that a third dimension was as im-
possible as It was mconceivable ?

Such a race of beings, conscious only of two dimen-
sions, is indeed not unimaginable. Some have even
theorised that a sightless snail, crawling from surface to
surface, has no concept of any third dimension, but
exception might be taken to the blind snail as an e.xample
of a Flatlander, for possibly his body might occasionally
lap the two sides of a flat stone as he curled over the
edge of it. But one can imagine a blind snail-like being
of such minuteness that the smallest particles of all other
matter were much larger than its body. Such a crea-
ture, though three-dimensional itself, might well have no
suspicion of any dimension beyond infinite surface. It
matters not in the least whether no such snail exists.
The fact remains that such existence is imaginable, and
that it is evident that in such a state of existence sceptic-
ism as to the possibility of a third dimension of matter
would be just as deep and instinctive as ours is against
the possibility of a fourth.

We may conclude, then, that our limiting of the num-
ber of dimensions possible to space to three, is due to the
circumstance that as we are constituted our senses cannot
conceive a fourth. To say that, therefore, a fourth does
not or cannot exist is to go further than we have warrant
for. But though we cannot see or by any sense perceive
a fourth dimension in addition to length, breadth, and
thickness, we may be able reasonably to infer something
about the character of such a hypothetical dimension,
assuming, for the sake of discussion, that it may exist.

Some of the properties of a fourth-dimensional " super-
solid" have been dealt with by more than one writer,
notably by Spottiswoode, in his Presidential Address to
the British .\ssociation at Dublin in 1878, and by
Howard Hinton, in his interesting little volume on the
subject of the Fourth Dimension.
I A suggestion is often met with that Time is the fourth
! dimension of matter. Time may indeed be looked upon
as a svmbol of the fourth dimension -an illustration of
the possibility of a direction which is neither up nor
down, nor from side to side, for in time are there not for-

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

as a
point, line,
meaningless

ward and backward directions which are neither of these'
and which are extraspatial ? But, except in this figura-
tive sense, the introduction of time as a solution of the
fourth-dimensional question is merely a confusion of the
problem. Time does not belong to the same category of
thought with length, breadth, and thickness. Point,
line, surface, solid - these follow each other
development in orderly sequence, but
surface, solid, time— these terminate in a
1:011 sequitiir.

Again, we may say that as a point is to a line so is a
line to a surface, or we may say that as a line is to a
surface so is a surface to a solid. This is intelligible, but
to add, as a surface is to a solid, so is a solid to time, or
to any portion of time, is unintelligible nonsense. More-
over, the concept of time does not strike one as being (as
the conception of a sphere would be) impossible to
Abbott's Flatlanders, whereas it ought to seem even
more so if it were actually two dimensions ahead of
them. Indeed, it ought to seem impossible to oursehes,
unless we are fourth dimensional beings.

But without confusing the issue by incongruously
introducing the concept of Time into the province of
Space, let us see what may reasonably be conjectured as
to tourth-dimensional existence.

The elements of the inquiry are strikmgly illustrated

by Hinton in some such way as the following :

Two points joined = One line.
Two lines joined = One square.
Two squares joined = One cube.
Two cubes joined = One (?).
The series may iie set out in this way: —

tion of more than three-dimensional form. The figure for
the super-cube would, in fact, be like this:—

>j. ^--

,y^y^

^ ^

:^./

Fig. I.

As the drawing of a cube to a Flatlander would seem
to be only two squares on the same surface united by
hnes also on that surface, so to us the above figure can at
most only convey the idea of two cubes united by lines or
perhaps by surfaces. We shall see this better if we draw
the figure m perspective stereoscopically and examine the
result m the stereoscope, when the two drawings will
blend into one apparent solid. Here is such a stereoscopic
diagram of the super-cube : —

No, of Terminal
Himensions Points.

Joining
Lines.

Point

Line

S(|uare

Cube

Siij)er-rul)e

Before we proceed to deal with the perspective repre-
sentation of the last in this series of figures, the super-cube,
it will be well to put ourselves back in imagination into
.Abbott's Fldtland, and to consider what would be our
b'latlander's impression of the perspective representation
(jf the ( ube. '• Here is no third dimension," he would
say ; ■' here are but two squares with lines joining them."
lo us, who are accustomed mentally to connect such a
figure with the similar retinal image which a solid cube
forms in our eye, the concept of a third dimension is
conveyed by association of ideas, but with the Flat-
lander no such association of ideas would exist, because
he would have had no experience of " thickness,"

him a Flatland
ines. .Similarly,
a full-face view of a cube would of course be to
him simply a square, and in fact cannot be otherwise
rendered on a flat surface.

Now our relations to fourth-dimensional diagrams must
be analogous. It is possible that we miglit make a
pictorial rendering of a super-cube on paper, which to a
being with senses capable of appreciating fourth-dimen-
sional space would be suggestive of a fourth-dimensional
super-solid, but to us, with no association of ideas to aid
us, the figure must not be expected to afford a representa-

experience
and the figure would remain for
one — two squares joined by four "

Fig. 2.

This slide, when seen in the stereoscope, shows us a
peculiar looking figure, apparently three-dimensional.
Now just is the perspective drawing of the cube suggests
one tliree-dimensional figure to us but to the Flatlander a
pair of united squares, so the above stereogram repre-
sents a pair of united solids to us, but to beings with
fourth-dimensional perception it might convey the notion
of one super solid.

It becomes e\'ident, therefore, that while our senses are
(as at present) limited to three dimensions, we cannot ex-
pect in the way thus far indicated to get any nearer to a
concept of the super-cube.

\'et there remains an experiment which carries us just
a step further, and brings us to the \'ery verge of a solu-
tion of our problem.

Before we make this experiment it will -again elucidate
the matter if once more we imagine ourselves for the
moment in Flatland. There the drawing of a cube directly
facing us would, as we have seen, be only one square, or
more strictly one square exactly behind another. To the
Flatlander, who does not know what " behind " means, it
would be as though the two squares occupied the same
space at the same time.

Now the analogy from this is obvious, for in the same
way under similar < ircumstances the super-cube of fourth-

Mar., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

dimensional perception would to our perception seem like
two cubes occupying the same space at the same time.
They would really represent two separated rubes, but
sejjarated in a direction neither up nor down, nor side-
ways, nor cross-ways — in a direction of which we, with
our three-dimensional conceptions, have no coj^nizance, just
as the I'latlander had no cognizance of the meaning of a
square being " behind " another square. The ()erspecti\e
view of the cube when not seen full face would show tlie
Flatlander the two squares only partially occupying the
same space at the same time. In like manner we may
put it that the super-cube, if presented to us broadside,
would look like two cubes occupying the same space
at the same time, while in other positions the two cubes
would only partially occupy the same part of space.

Now of this we can get some sort of representation by
an interesting experiment with the stereoscope. Just as
two flat drawings will give a representation of solidity
when appropriately drawn and placed in that instrument,
so two solids viewed through it will give some sort of idea
of the super-solid.

The experiment is striking and remarkable. Place in
the centre of the field on each side in a stereoscope a
solid cube. On looking through the instrument the two
combine, and one cube is apparently seen. Now while
looking at this one cube move slightly either of the culies
as it lies in the stereoscope, and it w-ill be seen that our
apparent one cube was composed of two occupying the
same space at the same time. With the movement of
one cube it is seen to pass partly out of the other, and we
have an impression as to our super-solid exactly the
counterpart of the Flatlander's impression of the cube as
shown to him in the perspective drawing, first full face
(the two squares occupying the same space and appearing
as one) and then a more side view in which the two
squares only partially occupy the same space.

Using a cube on one side in the stereoscope and a ball
of approximately the same size on the other the effect is
still better seen, and without moving either the strange
spectacle is revealed of a sphere and a cube occupying
together the same part of space.

The experiment affords, of course, but a suggestion of
the fourth dimension, yet taken for what it is worth that
suggestion is pregnant and of no small interest.

Conducted by F. Shillington Scales, f.r.m.s.

Microscopical Materia.1.

By the kindnoss of Mr. \V. S. Rogers, of I'pper W'arling-
ham, I was able la.st month to offer to the microscopical readers
of " Knowledgk anij Scikntific Nkws" some "Comfrey"
leaves (Symphytum ojjkuiale), which show well the beautiful
basesof the leaf hairs. Mr. Rogers states that the appearance
referred to is not seen in the leaves when fresh or when dried
underpressure, but would seem to be brought into prominence
by the blackening of the leaves when they lie fermenting on
the ground in autumn. He adds that the material is intract-
able to handle, the dried leaf being brittle and inclined to curl,
and he has therefore punched them into '^ inch circles. They
should, of course, be mounted as opaque objects. I regret
that by a printer's oversight this notice was omitted last
month, whilst the coupon was omitted the month before, thus
causing unnecessary trouble to my many correspondents.

Preserving Specimens of Orthoptera.

A recent number ol tlir American J fin mil c/ .IpplicJ
Mtcioscopy contains some interesting suggestions for preserving
specimens of Orthoptera. .'\s the writer says, (heir compara-
tively large size, juicy bodies, when alive or just killr-d, lirittle-
ness of limbs and antenii.e wlien dried, llieir pronencss to
fading after death, and their liability lo the attacks of mould
and nuisciun pests, all seem to conspire against their preser-
v.itiou. The larger and more showy specimens are best
known, and the smaller and less brightly coloured forms are
either entirely unknown or ha\e come to the notice of the
\ cry few specialists who have ventured into an .almost forsaken
field. There is, therefore, a rich field for investigation for
any microscopist who is in want of a fitting direction for his
studies.

Placing these insects in alcohol and other li(|iiid preserva-
tives has, in fact, overcome the objection to the soft juicy
bodies that so (juickly shrivel and liecome discoloured wlien
treated by the ordinary means of pre.serving insects ; but il
has the disadvantage of ijuickly effacing the many bright
colours conunon to such large niuubers of them, and even
changes miiuite structural characteristics, ,so as to render the
insects difficult of recognition. It al.so adds greatly to the
space taken up l)y the collection, and renders their trans-
portation difficult. Still it is an effective preservative
against insect pests, such as Dcnncstcs, Sec. Orthoptera can,
however, be handled "taxidermically " — ('.f., stulTed much as
birds, &c., are stuffed. Instead of throwing the insects into
spirits, they should, when captured, be killed in the cyanide
bottle. The specimen being then hold in the fingers and
thumb of the left hand, with a fine, sharp-pointed pair of
scissors open the .abdomen by cutting across the middle of
the two basal segments on the lower side, then reverse and
cut the opening a trifle larger by nearly severing the third
segment. Then extract all the insides (intestines, crop,
ovaries, &c.). along with the juices, using fine forceps for this
purpose, and wipe out the inside with a small wad of cotton.
This being done, the insect may be pinned into a box or
wr.ipped in paper and packed away for future use.

The "stuffing "is carried out as follows. Cut some raw
cotton into short pieces, and fill up the insect through the
opening made as above, using similar fine forceps and taking
care not to stretch or distend the ,al)domen beyond its original
dimensions. When the filling is completed draw the edges
of the severed segments carefully together, and press the sides
of the abdomen into sh.ape with the fingers. This can all be
done, after a little pr.actice, in four or five minutes' time. It
will be found that the insect will not decay or turn dark, the
original colours will be almost entirely preserved, and there
is but little danger of attack by museum pests, on of the mould
which so frequently spoils objects which .ire long in drying.

Mouldy specimens can often be saved by being pl.iced in a
tin box between wet cloths or blotting p.ipers well sprinkled
with dilute carbolic ,icid, and left for twenty-four hours to
thirty-six hours, or until sufficiently soft not to break when
h.indled. Then pour some alcohol into a dish, and .add to it
about one-twenfieth as much liquid carbolic acid. With a
camel-hair brush carefully clean the entir(^ insect, taking care
to wash every portion with the niixttue of alcohol and acid.

In arranging in the cabinet the suggestion is made that
nuich sp.ace can be economised by directing long antennas
backwards along the sides of the insect, and by folding and
crossing the legs beneath the body. In the Saltatoria. or
jumping forms, the pin should be inserted near the back edge
of the pronotum, a little to one side of the middle, .and direct-
ing it to the rear, letting it pass downward through the meso-
thorax, tliereliy tightly fastening together the two sections of
the body. In the other forms, Bliillnidfd, Mmtlniiltn. and
Plmsiiinuic-ii, the pin should be inserted l)ehind the pronotiuu
through th(t middle of the body, taking care to select a solid
portion for this purpose, without running the pin through the
basal portion of any of the legs.

The "Argus" Attachable Mechanical

Stage.

This stage was designed for use with the "Argus" micro-
scope, noticed in the January issue of " Knowlkdgh," p.age 21,
but it can be fitted to any ordinary microscope, being attached

KNOWLEDGE & SCIENTIFIC NEWS.

[Mar., 1904.

by means of a thumb screw only. It is decidedly original in
design. .\ friction wheel, actuated by a single milled head, is
in contact with a broad brass plate attached to the clips which
hold the slide. A steel spring gives the necessary pressure,
and the spindle bearing the friction wheel and milled head is
movable on a vertical pin. A glance at the illustration will
make the principle clear, and it will be seen that the stage

S^^^j

BOjI

,^■■1

travels readily m a \ertical or horizontal direction, or in any
intermediate diagonal direction, according to the position in
which the milled head is held whilst rotating. Check pins in-
dicate the horizontal and vertical positions respectively. By
this means not only are rectangular movements obtained, but
any desired diagonal movement is obtained in addition. The
whole stage works with great smoothness and sensitiveness.
The mechanism is entirely on one side of the stage, so that
none of the working parts are in the way of the instrument.

Quekett Microscopical Club.

The 409th ordinary meeting of the Club was held on Decem-
ber is. at 20, Hanover Square, W., the Vice-President, A, D,
Michael, Esq., F.L,S., in the chair, A most interesting col-
lection of diffraction gratings of various kinds was on view,
and the exhibitor, Mr, Julius Rheinberg, F,R.M.S,, briefly
described them and pointed out the curious optical effects
obtainable. Among the most interesting of the exhibits was
a reflecting diffraction grating on plate glass, silvered on the
grating side, ruled by Colonel L. Paxton, of Chichester, It
consisted of intersecting systems of circles. Each system
consisted of a series of excentric circles, the locus of their
centres being an intermediate circle. When exposed hori-
zontally below a flame, an observer stationed a few yards
away could see four intersecting rings of light stereoscopically
projected several inches in front of the mirror, whilst a
similar system of rings was seen several inches behind the
mirror,

Mr, Rheinberg then read a paper ''On an Overlooked Point
concerning the Resolving Power of the Microscope." It dealt
with a discovery made from the theoretical standpoint some
years ago by Dr. Johnstone Stoney, F,R.S,, which had only
recentlv been practically demonstrated — viz., that an objective
would resolve and separate two dots or Imes of a known
distance apart, although unable, owing to its N,.\,, to resolve
a series or band of dots or Hues at equal similar intervals.
The experiment was practically demonstrated to the Club, a
Grayson test plate of 15,000 lines to the inch being used for
the purpose, with a Zeiss S mm, apochromat. and a 27 mm.
compensating ocular.

Mr. D. J. Scourfield, F.R.M,S,, then gave an epitome of the
third part of his Synopsis of the British Fresh Water Entomo-
straca. It dealt with the ( Jstracoda, of which we have about
62 species, nearly all widely distributed ; the Phyllopoda, of
which there is only a single form now recorded, another form,
.•l/j».s£((Hi-n/o>-;«/s,being apparently extinct: and the Branchiura,
with two species, one lieing extremely rare. This was the con-
cluding portion of Mr, Scourfield's valuable series of papers
on the British Entomostraca,

The 410th ordinary meeting of the Club was held on
January- 15, the President, Mr,-(ieorge Massie, F,L,S,, in the
chair. There was a large attendance, Mr, C, Rousse-
let, F.K.M.S., read a paper ou '■.\ New Freshwater Poh'zoon
from Rhodesia," which was illustrated both by a diagram and
by specimens shown under the microscope. The polyzoon
referred to differs in many ways from all other known species,
and is especially characterised by the production of elliptical

statoblasts having five spines at each end, the spines being
armed with minute hooks,

Mr. J. T. Holder exhibited an interesting series of lantern
slides of Foraminifera from photographs taken by himself.
The specimens varied much in size, some of the large groups
being J inch in diameter, and containing several hundred
selected specimens from -jifj to i inch in diameter. .\ 4-inch
objective was used, and in spite of the difference in focal plane
the photograph was quite successful. Other photographs were
taken with 2-inch and i-inch objectives. The exposures varied
from a few seconds to three quarters of an hour, an isochro-
matic screen being invariably used. The camera and ap-
paratus emploved were also shown on the screen.

Mr. Earland ga% e a brief description of the slides, and con-
gratulated Mr, Holder on his success, and especially on the
way in which the glassy transparency, which was one of the
most beautiful features of the hyaline Foraminifera, had been
reproduced in the photographs. .'Attention was particularly
drawn to Frondicutaria aluta from Cuba, found at the depth of
700 fathoms. The genus was now almost extinct, but was
abundant in Secondary times. .\t present it was found in
numbers in only two small areas in the world, each widely
distant from the other, namely, the Caribbean Sea and the
shores of New Guinea. .Attention w-as also called to the great
difference in the form and structure of the specimens shown
on the screen. This was due to the different methods of
growth, which, in turn, w-as a result of the difference in size of
the primordial chambers. It was a typical instance of dimor-
phism, and the two specimens represented the megalospheric
and microspheric types respectively. Two especially interest-
ing slides were Polystomella craticiilata and Orhulina uiiii-ersa.
In the first the foraminifer was show-n side by side with
a cast of the animal's body, the cast being quite perfect,
and exhibiting every detail of structure, the canal system
and primordial chamber being sharply marked on the
screen. In the slide of Orhulina iinivirsa some of the
spherical details had been laid open in order to show
the internal Globigerina shell. This was shown in various
stages, from the perfect shell, attached by five spines to the
inner surface of the sphere, and not distinguishable from a
pelagic Globigerina, to the last disappearing chamberlet. The
mystery of these internal chambers, which were only found in
a small percentage of specimens, was unsolved ; but a theory
had been invented to account for them. It was supposed
that the pelagic Globigerina, in order to protect its delicate
spinous shell from the action of the waves, formed a spherical
shell outside it, and the internal shell being then of no further
use was gradually absorbed ind disappeared. A number of
photographs of rock-sections next exhibited showed Foramini-
fera ill situ, and exemplified the important part played bv
them in the structure of the earth, more important than all
other animals put together. They were amongst the very
earliest inhabitants of the earth, their remains being found as
far back as the Lower Cambrian strata, and some of the
genera, perhaps even species, found there were still in exis-
tence. They formed enormous masses of limestone in carboni-
ferous times, and the gault and chalk were largely composed
of their remains. But they reached their greatest develop-
ment in Tertiary times, when the famous Nummulitic and
.\lveolina limestones were built up by them, the deposits
stretching in an almost unbroken series across Europe and
the western half of Asia, reaching a thickness in places of
many thousand feet. Their modern representatives were both
small and infrequent.

In addition, a number of marine organisms, admirably pre-
served, were shown under microscopes on behalf of Mr, H, J,
Waddington, a former member of the Club,

Royal Microscopic.\l Society, December 16, Dr. Henry
Woodward. F,R,S,, President, in the chair. Mr. F, W, Watson
Baker exhibited under microscopes an exceedingly complete
and valuable series of slides, 16 in number, illustrating the
development of an ascidian from the fertilization of the ovum
to the larval stage. The slides were prepared by a gentle-
man well known to many of the Fellows, who had been
most successful in his management of marine aquaria. Dr.
G. J. Hinde read a paper " On the Structure and .^.ffinities of
the Genus Pomsphara." which was illustrated by diagrams,
mounted slides under microscopes, and specimens, many col-
lected by Dr, Hinde in his garden at Croydon, which had

1904.]

KNOWLEDGE .t SCIENTIFIC NEWS.

been weathered out of the chalk. — January 20, Annual Meeting
the President, Dr. Henry Woodward, F.K.S., in the chair.
The Curator, Mr. C. Kousselet, e.xhibited an old microscope
by Plossl, of Vienna, which had been sent on approval. It
has a folding tripod foot which carries a short column sur-
mounted by a compass joint for inclining the instrument. To
a hinged attachment of the compass jomt a triangular steel
bar is fixed. On this bar slides a bracket, having a curved
arm, to which the body of the microscope is secured. A
rack is sunk into the base or b.ack of the triangular bar for
the coarse adjustment, the pinion of which is contained in the
sliding bracket. The stage, which is also carried by the
triangular bar, has slow rectangular movements of very
hniited extent. There is also a micrometer movement, right
and left, for measuring objects, and a fine adjustment lor
focussing. There are six object glasses which can be used
separately or in various combinations of two or three glasses.
Among the apparatus is a lenticular prism for illuminating
opaque objects and two diaphragms for reducing the diameter
ot the reflecting surface of tne mirror. The ballot for officers
and Council for the ensuing year was then taken, and Dr.
Dukinfield H. Scott, F.K.S., was elected President. The other
business of the annual meeting having been disposed of. Dr.
Henry Woodward, the retiring President, proceeded to give
his annual address, taking as his subject " The Involution of
Vertebrate Animals in Time." His paper was illustrated by
diagrams, drawings, and slides, about So in number, shown
upon the screen.

A Novel Electric Traction System.

In No. 2 of the EUktrotechnischer Anzcigcr E. Leuggenhager
describes an electric railway traction system which is being
developed at the present luoinent by a Swiss " Studiengesells-
chaft," appointed for the purpose of finding out an electric
railway system suitable for that country, which, on account of
her dependency on the foreign coal market, evidently should
endeavour to utilize her wealth in hydraulic power. Speeds,
on the otuer hand, are limited there on account of the steep
gradients, small curves, and numerous stoppages. The system
in question uses steam locomotives hentai by electricity. Elec-
tric heating, as is well known, will work with the highest
possible ethciency, so that the total efficiency will mainly
depend on the output of the mechanical part of the locomo-
tive, being the steam-engine proper. Any coal steam loco-
motive could readily be converted into an " electrothermical' '
locomotive by simply replacing the fire-box and boiling-tube
of the boiler by a number of parallel electric heating-walls
rumiing througnout the boiler and being co[nposed of two
copper or iron sheets. The author suggests using in this con-
nection the well-known Prometheus heating elements. The con-
sumption of current would depend on the consumption of steam.
Let the boiler be designed lor accommodating 4000 litres of
water, which are to be brought within 3 hours from 10' up to
about igo^ C, corresponding with a steam pressure of 50 kg.
per sq. cm. In the case of an efficiency only as high as 90 per
cent, the following data would be obtained : 4000 1. of water
would require, in order to be brought to the above tempera-
ture, 4000 X iSo = 720.000 kg. cal. ; i kg. cal. = 1275 eft.
watt, hours, therefore 720-000 kg. cal. = about goo eii. kw.
hours, or, distributing this amount over 3 hours = about
300 kw. A consumption of steam of 1000 kg. per hour would
accordingly require a supply of current of about 225 kw. As
regards the advantages inherent in theelectrothermic system,
the resistance of the steam accumulator against current shocks
should be mentioned. There is the further advantage of both
direct and alternating currents being practicable in this con-
nection, any desired combination being suitable. The mean
efficiency of electrothermic locomotives, being about the same
as that of an electromotive machine ot the same size, would
be about 5o to 70 per cent., whereas the total efficiency of a
railway system, on account of the more advantageous utiliza-
tion of tne load, would be higher for the former. Further-
more, the adoption of electrothermic service may take place
gradually, being much easier than that of electromotive
service, on account of the lower cost of the conversion and
the easiness with which the personnel may be trained for the
new service. A possible conversion of electrothermic into

electromotive railway service would finally be readily made
should the electromotive service in future be so improved as
to become superior to the electrothermic system. — A.G.

Geodetical Irvstrvirrvents.

I'roiii Mr. James Hicks, of llatton Ganlen, we have rcceivcil a
calaloguc ol the new types oi liaiul surveying instriuncnts designed
and patented by Sir Howard (hubb. I-".K,S. 'iliese extremely
ingenious and tisclul instruments were designed by the inventor
primarily (or the use ol those wliose work in surveying required
simple, portable, and easily compreliensible instruments lor rapid
work, file principal advanl.ages common to all the instruments
.ire tlie film surface of the glass, which is of a kind capable both of
rellecting and transmittin.n a considerable portion of the light which
lulls on It ; and the adoption of the collimator system for parallel-
isiny ra\s. Hy the use ol the Keynolds-tjrubb film, light Irom two
diflerent directions can be directed into tile eye of the oliscrver
without recourse to the inconvenient old method which was known
;is "dividing the pupil." The collimator system of parallelising
rays has also great atlvantages in convenience and simplicity of
observation. Among the instruments to which these methods
have been specially and advantageously applied are the small clino-
meter and prismatic compass and a level. Mr. llicks also com-
prises in liis catalogue of these new types ol hand surveying in-
struments, an optical square fitted lor use with the naked eye, an
attachment for a telescope, a graphonieter, and a pocket surveying
instrument.

REVIEWS OF BOOKS.

Who's Who, ys. Od. (A.&C. Black), grows stouter every year,
and now contains no fewer than 17,000 biographies. Its great
usefulness is so well recognised that it need not be dilated
upon. Some few of the biographies might, one would think,
be curtailed, especially as regards " recreations," one of which,
we note, reads " homely table games of cards, chess, Ijack-
gammon, halma, cribb,age, &.c." Otherwise, the succinct ac-
counts of the lives of every Englishman of any note are most
complete, and just what one requires.

Who's Who Year Book, is., is a small book containing the
tables which were formerly incorporated in Who's Who, but
which have been deleted from time to time to make room for
the evcr-increasin.g number of biographies. These tables are
most useful for reference, including as they do not only .such
as are to be found in many other annuals, but also lists of
Koyal Academicians, Bishops, Newspapers and Magazines,
l^seudonyms and Pennames, Principal Schools (with number
of pupils and cost), I'ellows of the Koyal Society, Societies,
&.O., Chairs and Professorships, Heirs of Peers, iS;c.

The Englishwoman's Year Book, 2s. 6d. (.'\. &. C. Black), " aims
at giving some idea of the extent of women's work and
interests, and some guidance to those who want to help their
fellow-creatures, whether as individuals they live lives of
which their own home is the centre, or take a wider view of
their opportunities and responsibilities,'' and has a wonderful
mass of useful information packed into its 350 pages.

BOOKS RECEIVED.

[I'he notice oj books in this column does not preclude the revieio of
them at a later date).

Studies in Hcterogenesis, by H. Charlton Bastian, M.A.,
.M.D.Lond., F.K.S. (Williams and Norgate, one vol.; price
31s. 6d.) .\ monumental work, illustrated with more than
eight hundred micro-photographs, and summing up the whole
number of instances of the apparent transformation of the
substances of parent matrices into new forms of lite. The
author examines the alternativ'C explanations of these pheno-
mena— (i) That the resulting forms of life are due to the
invasion and multiplication of parasites within what appear
to be parent organisms ; (2) that the resulting forms of life
are in reality heterogenetic products originating from the
very substance of the organisms from which they proceed — -
and gives his reasons for adopting, after prolonged and care-
ful study, the second of these theorems.

KNOWLEDGE & SCIENTIFIC NEWS.

AR., 1904.

The Worship of the Dead, by Colonel J. Gamier. (Chapman
and Hall, one vol.). Colonel J. Garnier.s work on "The
Worship of the Dead" (Chapman and Halli deals with the
origin and nature of Pagan idolatry and its bearing upon the
early history of Egypt and Babylonia. The voluminous
materials collected by previous writers on the subject are
here set forth within a moderate compass and in a readable
form. The book is profusely illustrated with interesting
examples of the statues of ancient gods.

Cassell's Popular Science (Cassell and Co.). edited by Ale.x-
ander S. Gait, with contributions from T. C. Hepwort'h, Pro-
fessor Bonnev. Frank Weedon, John Fraser. F.L.S., Wilfred
Mark Webb. F.L.S., Dr. .\ndrew Wilson. Dr. Bernard Hol-
lander, and William Ackroyd, F.I.C. The subjects range from
radium to carnivorous plants, and from the transit of Venus
of 1SS2 to the working dynamo. The articles, of which there
are some sixty, are clearU- and well written, and in every
respect justify the title under which they are collected.

British Tyroglyphida, by Albert D. Michael. F.L.S., F.S.S.,
&c. Vol. II. (Printed for the Royal Society.) This volume
contains the description, with plates, of the genera and species
of the British Tyroglyphids. from the genus Chortoglyphus
to the Tyroglyphus Wasmanni. .\ list of foreign species is
added.

The Old Testament and Historical Records, bv Theophilus
Pinches. LL.D. lOne vol. Second Edition. S.P.C.K.l In
the second edition of the " Old Testament in the Light of the

Historical Records and Legends of Assyria and Babylonia,''
Dr. Pinches adds some exceedingly valuable and interesting
matter on the Laws of Hammurak. together with a translation
of the laws and notes on Delitzch's lectures on this subject.

A School Geometry. Parts I.-V. By H. S. Hall, M.A.. and
F. H. Stevens. M..\. (Macmillan. One vol. ; price 4s. 6d.) —
This is a publication, in one volume, of a geometry for schools
based on the recommendation of the Mathematical Associa-
tion and on the new Cambridge syllabus.

Descriptive Chemistrj-, by Lyman C. Newell. Ph.D. One
vol.. with supplementary vol. of experiments. (London:
D. C. Heath; price 4s. 6d. and is. 6d.i — Intended for teachers
who wish to emphasise the facts, law-s. theories, and applica-
tions of chemistry. The experiments have been prepared for
limited laboratory facilities.

■^^ rf^> -^i ^^ ^*i

CKess Problems.

Owing to the great amount of matter which we have on hand
we have felt it necessary to again postpone pubhshing the
Chess Problems. We should be very glad to have the opinions
of those interested in this subject as to the continuance or
otherwise of the Chess Column.

LAST YEAR'S WEATHER— MARCH, 1903.

DISTRIBUTION OF MEAN TEMPERATURE.

RAINFALL.

♦•96

1^2 It

/ ■■■5S«(

"'^^ AoeV. 3 86 V*

2 02

C^I30i 6-24.. «^ '♦e2» . 180 ...

,1 65

* S6»^_/-^

9L,

The general distribution all o>fr <iur islands agreed \ ery fairly
with the normal, but the actual \alues\\ere above the average
in all localities excepting the west and north of Ireland.

3-74. *"^.^ 3,90

339

Rainfall »a.- considerably in excels of the average over the
countr>' generally, but was rather deficient on the east coasts
of England and the north-east coasts of Scotland. Over the
western half of the Kingdom the excess was very large, the
amount at manv stations being more than double the average.

KDomledge & Selentifie flems

A MONTI II A' JOURNAL OF SCIENCE.

Vol. I. No.

[new skrifs ]

APRIL, 1904.

E Entered at 1
Stationers' Hall.J

SIXPENCE.

> Contents and Notices. — See Page VII.

The Protective
Resemblance of Insects.

By Percy Collins.

The story of insect life has many phases of entrancing,'
interest ; nor is this altogether surprising when we
remember that the earth, the air, and the water are alike
peopled by the vast army of the six-footed. These varied
conditions of life have left their mark not only upon the
habits and movements of insects, but upon their colour,
their form, and their instinctive attitudes of repose. So
that although insects are more diverse than any other
natural group of living creatures, the explanation is
simple; they are and have been subjected to almost every
condition under which life is known to be possible.
Thus, to the entomologist, every difference of form,
colour, or attitude seems worthy of serious investigation.
He realises that an unusual tint or a quaint pattern carries
with it a definite meaning — that it is in some way linked
to the ancestral history of its possessor. Often enough
this meaning is mysterious. But occasionally the colours
and form of an insect, or of a group of insects, can be
explained as the direct outcome of certain known in-
fluences. Not infrequently such interpretations reveal
the fact that the shape or colour of an insect, or both in
combination, are mainly responsible for its well being.
The creature's peculiar appearance either mystifies its
enemies or enables it to approach unobserved the smaller
insects upon which it preys. The whole subject, to
which the general term " mimicry " is commonly applied,
constitutes one of the most fascinating phases of entomo-
logical study.

The simple protective resemblance of an insect may
be either general or special. That is to say, the protec-
tion may originate in the mere likeness of an insect's sur-
face colouring to that of its customary surroundings, or
it may consist in an actual reproduction in both form and
colour of a certain object with which the creature is
commonly associated tliroughout its life.

Instances of general protective resemblance must be
familiar to observers in all countries. The numerous
moths which are accustomed to rest for hours together
upon rocks or tree trunks are oft-cited examples. Con-
spicuous among tliem is the whole genus Calocala, the
various species of which are widely distributed in the
Pakvarctic region and elsewhere. These moths have
brightly coloured hind wings, the usual tint — which has
given to them their popular title of " Red-underwings "
— being some shade of crimson or pink. When they are
on the wing they are sufficiently conspicuous, and are
liable to be snapped up by a hungry bird. But when at
rest upon a tree trunk in tlieir customary attitude of
repose, the soft grey or brown colour of their fore wings
produces a general effect so well in keeping with the

Catocala sp, Japan.

Catocala sp. Japan. At rnst on bark.

rough surface of the bark, that they are' extremely diffi-
cult to detect. Their colour pattern alone constitutes a
most effectual hiding.

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

The same may be said of countless other moths, especi-
ally of the great Noctiia group ; and it is interesting to
trace how closely the colour of the fore wings in a given
species corresponds to its habitual resting place. The
appearance of all kinds of bark, of moss}' twigs and of
lichen-covered rocks is faithfully reproduced ; nor is it
necessary to search beyond the moths of our own islands
for striking examples.

Many butterflies, especially of the great group .Vvw;/'/ia-
liiuv, possess — in the tints of their under side— a general
resemblance to the ground upon which they habitually

Hamanumida dedalus. Africa.

settle. Moreover, many species seem to have acquired
the trick of inclining their folded wings out of the
perpendicular, by this means covering, or minimising,
their own shadow, as well as bringing the protectively
coloured underside into more prominent view. This
habit may be observed in many of our common " brown "
butterflies — for instance, in Pyrarga mcgaera and in Satyvus
semde. In connection with this apparently acquired aid
to protected resemblance, the habits of Hamanumida
dcdalus, an African butterfly, are exceedingly interesting.
It is authoritatively stated that this insect rests in West
Africa with its wings folded over its back after the

soil, is exposed to view. In South Africa, on the other
hand, the same insect sits with its wingsexpanded, show-
ing the brownish grey upper side which harmonises with
the colours of the rocks in that region.

Many of the Coleoptcra, from their colour, are almost
indistinguishable when resting upon lichen-incrusted bark.
The accompanying photograph of a Longuorn from
Bhutan admirably illustrates this phase of general protec-
tive resemblance. Although the insects are in full view,
the casual glance quite fails to detect their presence.
This surprising result is largely gained by the manner in
which the colour is, as it were, cut up into dark and light
patches. This is particularly noticeable in the long
antenna", the sharp outline of which is entirely effaced
from their being coloured in alternate lengths of black
and grey.

Turning from general to special protective resemblance,
we find a number of extremely interesting and remark-
able examples, especially among exotic insects. The
butterflies of the genus Kallima — " leaf butterflies," as
they are popularly called — bear striking testimony to the

Hamanumida dedalus. (Underside.) .Mrica.

common habit of butterflies, in which position its tawny
under surface, which agrees with the general tone of the

Apallmna ducalis. Male and Female. Bhutan. On Lichenous Bark.

powers of natural selection. When flying in the full
sunlight, their wings flash with colour, but directly they
come to rest upon a twig they are, to all appearances,
brown and withered leaves. This sudden transformation
is made possible by the tinting of the under surface of
the wings, and by the curiously erect attitude which the
insect is able to assume — its wings drawn upright over
the back and its head and antennae concealed between
their anterior margins. When we consider the mar-
vellous accuracy of the colour imitation, the uncommon
shape of the insect's wings and its unusual pose, the leaf
butterfly must still be ranked as one of the most amazing
instances of protective resemblance yet recorded, not-
withstanding the many marvels which have been brought
to our notice within recent years.

The larvae of moths grouped under the title Geome-
tridcT usually bear a curiously accurate resemblance to
liitle twigs or sticks, both in shape and in their brown

April 1904]

KNOWLEDGE & SCIENTIFIC NEWS.

Kallima niachfs. India. Two Specinjens at rest among leaves.

or grey colouring. Moreover, this deception is materially
heightened by the unique attitude of repose obtaining
among these caterpillars, which differ from most lepidop-
terous larva; in possessing only two instead of five pairs
of pro-legs. These are placed at the extreme posterior

riul 111 the body, while the three pairs of true legs at the
other extremity arc usually exceedingly diniinuti\e. 'l"he
perfect stick-likeness is gained in the following manner.
The caterpillars of the GconulridfC usually feed at night.
When daylight comes, or under Ihe stimulus of alarm,
they take a tirm hold upon ilic iwig with their four pro-
legs and stretch out their cylindrit al body stiff and
straight at an acute angle. In this position they are
capable of remaining, absolutely motionless, for liours
together. But to counteract the terrible strain which the
attitude would impose u])()ii the body of the caterpillar,
each usually spins a strong, though practically invisible
silken thread from its mouth to the twig fin which it rests.
A family of insects remarkable above all otliers for the
almost universal protective resemblance of its members
is the Phasmida. In order to understand these creatures,
which are numerous in all tropical countries, it is neces-
sary to know something of their habits, llnlike their

Three Caterpillars ol Hemerophila abruptaria. l-.iifilaml

ClitumnuA Sundaicus. Stick-hke I'h.isiiiiil,

near relatives, the Mantidce or " praying insects," which
are voracious insect eaters, the Phasmida' are exclusive
vegetarians, feeding greedily upon the leaves of the plants
which form their resting places. In movement, Phasmids
are extremely sluggish, and many of the species — being
apterous or possessing, at most, only rudimentary wings —
are incapable of flight. Thus, they are much exposed to
the attacks of birds and other insectivorous creatures —
have been so, in all probability, forages past. This per-
secution might be supposed to foster any variation in
shape or colour likely to be of protective value. And, as
a matter of fact, the whole of the Phasmidce, almost with-
out exception, have undergone striking modifications in
the direction of special resemblance.

As a rule, the bodies of these insects have become
greatly lengthened, while the legs are long and slender.
Those known popularly as " walking sticks," of which
the Cliluinnus sundaicus shown in the accompanying photo-

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

graph is a good example, are generally of a uniform
brown tint. Many of the species have curious knotty
protuberances, or even prickles, upon their bodies and
legs, this, of course, adding much to the stick-like aspect

winged Phasmld, showing two portions into which each win^^ is divided.

of the insect. After examining a dried specimen of a
"stick" Phasmid, one does not need the assurance of
foreign collectors to believe that these creatures are prac-
tically invisible when at home among the branches of
their native shrubs.

Winded Phasmid. at rest among grass blades.

Other Phasmidce — fairy-like creatures with exquisitely
coloured wings — resemble grass rather than twigs when
at rest. Their bodies, legs, antennae, indeed every part
of them, with the exception of certain portions of the
wing area, is green. Their first pair of wings is rudi-
mentary ; but their hind wings are ample, gauzy, and
fan-like in their manner of folding. A narrow strip at
the anterior margin of each wing is thickened and green
in colour, contrasting strangely with the gauzy area,
which is usually bright pink. Under this narrow cover,
the whole of the bright, flimsy portion of the wing is
packed away when the insect comes to rest. And so
closely are the wings folded that the casual observer
imagines the creature to be apterous. It is, indeed, the
exact counterpart, of a crumpled or slightly-thickened
grass blade, while its legs and antenna;- are too slender to
attract much notice.

Phyllium sp. Female. Ceylon.

Perhaps the most remarkable genus of the Phinmid<r
is PhyUiuni, whose members — unlike the majority of their
allies, which we have seen to be slender and lengthened
— have the body and legs flattened into leaf- like plates.
In some instances this design of leaf resemblance is
carried out with amazing accuracy and attention to
detail. Every portion of the insect seems modified to the
one end. Its body is flat and leaf-like ; its wings and
wing cases (where present) look like leaves; while even
its legs are flattened and fitted with leaf-like appendages.
To crown all, the colour of these insects, when alive, is the
brightest and freshest of vegetable greens; so that, when
crawling among herbaceous foliage, a species of PhyUiiim
is, to all appearances, not an insect at all, but just a
moving mass of leaves.

Certain species of the Mcmhracidtc, which are ratlier
small, frog- hopper-like insects, have a most curious
thorn-like or knot-like appearance. This is gained by an
unusual de\elopment of the pronotum, which is produced
behind into a long process, or, it may be, into a kind of
shield. In the case of Ltnbonia spinosa, from Brazil, this

April, 1904.]

KNOWLEDGE .^ SCIENTIFIC NEWS.

process extends completely over the insect, and is drawn
upwards to a point. In fact, it is an exact imitation of a
sharp vegetable thorn, from which it is indistinguishable.
Thus, the Umboiiiii lias merely to crouch down upon a
thorny twig and withdraw its legs beneath the shieUl-
like pronotum to be completely hidden.

The above examples include some of the more striking
instances of protective resemblance, both general and
special. They must not, however, be regarded as even
typically exhaustive, for sticks, leaves, .mosses, and
lichens, though common patterns, are by no means the
only objects copied in insect colour and form, blowers,
seed pods or seeds, patches of mould or decay — even the
droppings of animals and birds are all prototypes for
insect disguise. Moreover, the modilications of form and
the varieties of colour and marking which ha\e been
called into being by the need for protection are too

Umbonia spinosa. Bra/il. (.Middle "thorn" on upper part of Stoiii).

numerous even to tabulate. In the course of his investi-
gations, every observant student will constantly have new
and striking instances brought to his notice, even though he
may never wander beyond the confines of his own county.
But it should be recollected that to form a true esti-
mate of the protective value of an insect's colour and
form, it is absolutely essential to study them in relation to
their habitual surroundings; for, as a rule, it is<iuite im-
possible to tell from a casual examination whether a
special appearance is protective or not. A butterfly in a
cabinet drawer is merely a scientific specimen. Its colours
may be bright and beautiful, dull and unattractive, as the
case may be ; but suspended above a surface of white
paper, they have no special significance. On the other
hand, when the insect is alive and among its natural sur-
roundings, its colour and shape are often seen to have a
direct bearing upon its well-being. Thus the study of
living specimens cannot be too strongly urged upon the
student — not of entomology alone, but of every branch of
natural history.

^^^^^^

A RATHER unexpected geographical discovery has been made by M
Gabriel Marcel, who in a Paris shop found an Eighteenth Century
map on which is shown the project put forward by M. de la Bastide
for a canal across the .\merican isthmus by the Nicaragua route.
The map. which is finely e.xecuted, is printed on silk, and from its
shape was clearly intended for the decoration of a fan. It shows
three ships in sail on the Lake of Nicaragua, and marks the
suggested route to the west of the lake Though M de la Hastide's
project is a matter of geographical history — he wrote a memoir on
it in 1791 — the map's existence had been hitherto unsuspected. His
was a plausible project, but he did not by any means realise its
difficulties, for he was a theorist who never visited the spot, and
who depended on the very inaccurate maps of other people

Professor
Adam Sedgwick.

The Man and his Work.

When, just over 30 years ago, at a meeting lieUl in the
Senate House, Cambridge, the idea was first mooted of
a memorial to Professor Adam Sedgwick, if was said of
him in the words of Shakespeare, " His life was gentle;
and the elements so mixed in liim that Nature might
stand up and say to all the world. This was a man."

It is well at this moment, wlien the Sedgwick Musemn
is an actual connnemoration, to recall the up-bringing
and achievements of the subject of this splendid allusion.

The son of a Yorkshire clergyman, Sedgwick', at tiie
close of his early education, proceeded to Trmity College,
Cambridge, duly took a degree, and was classed as 5th
Wrangler. In 1810 he was made a Fellow of his College,
and engaged in teaching; and in 1 81 6 was ordained. Hut
it was not as a divine that his repute became established,
but as a leader in British geology, a soldier in the early
campaigns of the science. Klected Woodwardian Pro-
fessor of Geology in iSiS, although knowing, we are told,
. omparatively little of the study he was to teach, it
seemed as if he was predestined for its successlul pro-
secution, and it was not long before he stepped into
the front rank as an original iiuestigator. His lectures,
which formed a novel feature when he entered up(}n
the duties connected with tiie Woodwardian Chair, at-
tracted general attention, while at the same time the
Professor lost no opportunity of promoting and en-
couraging the extension of natural science teaching in
the curriculum of university studies. Those were early
days in geology — in fact, the long-clothes stage and the
authorities looked askant at the iconoclastic science,
mindful, too, of what it might bring in its train. Un-
doubtedly, in the case of many other men, efforts to
obtain the recognition of geological and allied studies
would ha\e been foredoomed to failure in the face of
the frowning repressiveness which prevailed at Cam-
bridge. But Sedgwick was endowed with special quali-
ties for the task in hand, and never deviated from the
chosen path. Moreover, his charming personality and
adornments of character disarmed permanent opposi-
tion. Of these characteristics there is ample testimony
in the opinions (jf his contemporaries. Three prominent
hopes possessed his heart in the earliest years of the
Professorship, in his own words expressed thus : —
" First, that 1 might be enabled to l)riiig together a
collection worthy of the University, and ilfustrative of
all the departments of the science it was my duty to
teach ; secondly, that a Geological Museum might be
built by the University, amply capable of containing its
future collections ; and, lastly, that I might bring to-
gether a class of students who would listen to my teach-
ing, support me by their sympatliy, and help me by
the labour of their hands." The fulfilment of these
hopes is, of course, a matter of history.

Sedgwick was the author of a lengthy series of papers
in British geology, but he wrote no separate woriv. In
particular is he known for his elucidation of the Pala;o-
zoic system, in which he collaborated with Murchison.
He investigated the Magnesian Limestone of the North
of iMigland, and the geology of Wales engaged his
earnest and successful study. He was elected a Fellow
of the Royal Society in 1821, and in 1863 was awarded
the envied Copley medal -a year previous to the award

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

made to Darwin — for his observations and disco\eries
in tile Palaeozoic series of roclvs, and more especially for
his determination of the characters of the Devonian
system. Other honours were showered upon him, both
at home and from abroad, including, in the former
category, the Presidency of the Geological Society and
of the British Association.

As a contemporary of L)ar\vin, Professor Sedgwick
was confronted with that naturalist's theory respecting
the evolutionary order of Nature. His attitude was uni-
formly hostile to the hypothesis, and he would have
none of it. In this connection it is interesting to note
that, at the time of the publication of the " Origin of
Species," Darwin was exceedingly sore at the " rabid
indignation " displayed by Sedgwick, nevertheless he took
occasion to refer in affectionate strain to the veteran
geologist's noble heart and instincts.

Sedgwick never married. He continued his occupancy
of the professorial chair until his death, in i>^73, which
took place at the ripe age of eighty-eight, and he was
buried in the ante-chapel of Trinity College.

Finally, let these words of his further proclaim the
man : " My labour is its own reward. It gave me health,
and led me into scenes of grandeur which taught me to
feel in my heart that I was among the works of the great
Creator."

Telegraphically Trans-
mitted PhotogrsLphs.

By Dr. Alfred Grauenw it/.

Many attempts ha\e been made to transmit handwriting,
photographs, drawings, (S;c.. by telegraphic means, and the
more or less successful solutions which have been suggested
for this problem of late years are numerous. Selenium cells, as
shown by Herr Ruhmer's successful experiments in the field
of wireless telephony, give a ready means of detecting and
transmitting by telephone even very slight fluctuations in the
intensity of a source of illumination, and afford means ol con-
verting these fluctuations into oscillations of an electric current.
If a hght ray and a selenium cell be simultaneously drawn
along over opposite sides of a photographic plate, llie different
shades of the various portions of the plate will result in con-
tinuous oscillations of the current being produced in the cir-
cuit of the cell This is a common feature with all the sending
devices used in the instruments of this class. The current
oscillations are made to act on the receiving apparatus, which
will reconvert them in turn into fluctuations of light. The
design of the receiving apparatus has hitherto been the weak
point with all these systems, because the electric currents
transmitted are so Aery small. Hut a satisfactory solution of
the difficulties so far met with seems to be aflorded
apparatus of I'rofessor Arthur Korn.
presented before the French Academy

by the teleoptical
^Iunich, as recent! v
of Sciences.

While engaged in investigating the radiations given off by
the electrodes of a tube exhausted to a pressure ranging be-
tween 0-2 and 2 mill, as Hertzian vibrations were applied to
the electrodes. Professor Korn noticed the extreme seubitive-
ness with which these radiations would react on small altera-
tions in the circuit. This sensitiveness suggested a possible
utilisation of those radiations which were photographically
most efficient, in connection with a method of electrical tele-
photography.

The apparatus, based on the above principle, is shown in
fig. 1.

The photographic film a uf the receiver rotates in front of a
small window c (0-25 mm x 0-25 mm) in an exhausted tube /),
like a roller, in front of the \ibratiug membrane ot a phono-

graph. The surface of the tube is coated with black paper
and tin-toil, lea-i-ing only the window. By means of high fre-
quency currents (Tesla currents), luminous radiations may be
produced inside the tube, and these, after passing through the
small window, will make photographic impressions on the sen-
sitive film. The latter is moved synchronously with the image-
holder A of thesending-apparatus(afilm bearing the photograph
to be transmitted wound on a glass cylinder), which is traversed
by a very thin beam of light B C D while passing, line per line,
before a selenium cell D placed inside the cylinder. .According
to the different shades in the photograph transmitted, thesele-

SoKlif of

Light

'SjjtA I

Gxj^^acciXXf

Fig.

nium will receive more or less light, while an electric current,
passing through the selenium D and the telegraphic wire F up
to the recei\'ing apparatus, will undergo corresponding varia-
tions of intensity, thereby regulating the intensity of the
radiations of the receiving tube. This is provided for in the
following way: The active electrode e of the tube being con-
nected to one of the poles />, of the secondary coil of a Tesla
apparatus, by inserting fields of sparks formed by the points

Original Photograph.

Transmitted Photograph. ^ .»

nil, uij, of a galvaifometer needle / and two fixed points", fj, L,
the intensity of the radiations given off by the tube will be
more or less great, according to the distances nij fj and m,
and (2, which are variable along w-ith the transmitted currents
passing through the galvanometer i'. By the use of this
arrangement, a means is afforded of making the intensity of
the radiations of the receiving tube correspond with the in-
tensity of the light striking the selenium of the sending-
apparatus, thus reproducing line per line of the original photo-
graph.

April, 1904.1

Tlu

KNOWLEDGl*: \- SCIENTIFIC NEWS.

well.

i.ij lui- Litciiii may. as wen. serve as a
telautographical recciviiif;-apparatu:s. i.e. an apparatus for re-
producing handwriting, drawinsr. &c.. at groat distances. In
this case, only sonic ver\' slight alterations will liave to be
made, and .i BakewcllCaselli transmitter used. The
speed attained is relatively very high. It has been loinid
possible to reproduce from tueiitv to fortv words in the

Orig:inal Photograph.

original handwriting iu the course of \.hu-e minutes, and in th<
case of shorthand much higher speeds may be arrived .it.
The transmis.sion of photographs, of course, is slower, princi-
pally on account of a certain inertia of the selenium. Tin-
progress lately made in connection with the construction of
seleniimi cells', however, makes much higher speeds very prob-
able. The time at present required for telepholographing a
portrait is about half-an-hour.

Transmitled Photograpli.

Figs. 2 and 3 show the telegraphic reproduction of a photo-
graph and a telautographic specimen respectively. The in-
ventor wishes us to state that part of the imperfections of tlie
photo, especially the stripes, is due to the e.xperiments having
been made in the Physical Laborator\- of the Munich Univer-
sity, where the pressure of the battery and, accordingly, the
intensity of the source of light, would undergo frequent fluctua-
tions.

Modern Views of
CKemistry.

By II. J. II. l-E.MON, l-'.K.S.

In our last coiiunimiiation \\c indicated \er\ Ijrieth', in
outline, the nature ol the ionic-dissuciatiiui Ii\ polhesis,
and mentioned Slime of the expeiiniental fads upon wbicli
it is basi'd ; we propose now to ^i\e a few illustr.il ions oi
the manner in, which the lupothesis li;is been applied to
the explanatioir or inlerpret.ilioii ol sonic well known
chemical and physical laiis.

\\ hat is an ;u'id r' l'!\ei\one who is al all ai(|uamled
with the cleinenlar\ huts ol cheniislrx has a lairh clear
conception in his own mind what the term implies, but
attempts to frame an exact definition .are not always
satisfactory. If an acid is " an\' liydroi^eii compound
which can exclKuii.j(; its liy(ir<)<ien, wholly or [lartly, for a
metal when the latter is presentetl to it In llie form of a
hydroxide," we must include as acids substances suih as
zinc hydroxide and aluminium hydroxide, the distinction
between acid and base heiny relative rather than .abso-
lute. It was at one lime proposed lO' restrict the term
" true acid " to a. c,om|)oiui(l which can behave in the
abo\e manner even in presence of much water, and such
a restriction woidd, it is true, exclude substances like
zinc hydroxide, but it would al.soi exclude some com-
[loimds like silicic acid which are looked upon as acids.
Other definitions, such .is " a salt of hydrogen," " a
compound which can evolve water by its action, 011
caustic potash," or " a compound of hydrofjen with an
elect ro-ne£^ative element or group, ' ("an generally b(^
foimd f;uilt with, and there is often a tendency to define
the terms " acid," '' salt," " base " in a circle.

The ionic-dissociation hypothesis now comes to the
rescue with an elegant and .simple definition. ,\n acid,
it says, is :\ ccuiipoimd whose aqueous solution contains
free hydrogen ions. \\'hat we call acidity or acid-pro-
perty in a solution is due to these ions, and is more prf>-
noiinced as their concentration is greater, /.(■., the more
there are in a gi\en \-olunie. A base, on the other li.uid,
is a compound wlio.se aqueous solution conlains Irec
Indroxvl (() II) ions, and when an acid neutralises a
base the only change which takes place (provided the
solution is dilute and the acid and base are " strong ") is
the union of the free hxdroxyl and hydrogen ions to
form water. It will beobser\ed that, according to this
conception of the m.itter, neither the metal or acid
radicle takes any part in the change ; they remain as
free ions throughout —

H + K + M + O H =M -f- R -f- 11 0 H

(where K is the acid radicle and M the metal).

It must not be forgotten that the older definitioiis
alluded to above are practical ones, whei^eas thi.s ionic
definition depends entirely upon hypothesis ; the latter,
however, affords a remarkably simple explanation of
many well-known facts. When, for example, equivalent
weights of strong acids (say, hydrochloric or nitric)
neutr.-ilise strong bases (say, caustic potash or soda), the
quantitv of heat evolved is always the same. This fact
is easilv understood on the above supposition, since in
each case the only change in the arrangement is the
union of hvdroxyl with hydrogen.

If the ;icid or base, or both, are not " strong,'' the heat
change on neutralisation w ill be different from that in the
previous case. Thif. is explained by saying that the
weaker acids and bases arc not entirely in a state of

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 19O4.

" ionisation " or dissDciation to begin with, and require
to be further broken up bsfore the hydrogen and hydroxyl
can combine.

What exactly is to be understood by the strength of an
acid or a base was for a long time the subject of dispute.
It used to be said that sulphuric acid was stronger than
hydrochloric or nitric acids, because it " turned them
out" from their combinations with bases. Sodium nitrate,
for example, when distilled with sulphuric acid, gives
sodium sulphate and free nitric acid. The test of strength,
however, when applied in this manner, is not legitimate,
since the nitric acid is not given a fair chance ; it is re-
moved from the sphere of action by vaporisation. A
much more rational way of arranging the encounter
was that devised by Thomsen when he mixed, in
dilute solution, one eijuivalent weight of each acid
with one equivalent weight of base. Here there is in-
sufficient base to satisfy both acids, and all the substances
concerned, before and after the action, remain dissolved
together without any removal. The two acids then strive
for the base, and the one which gets most of it is the
" strongest." In this way it is possible to arrange the
acids in the order of their "strength," and experiment
showed that hydrochloric and nitric acids head the list in
such an arrangement.

Sulphuric acid proves to be only about half as strong
as nitric or hydrochloric acids— a result altogether at
variance with the older ideas.

The problem has been attacked also from various

other points of view : it is known, for example, that the

salts of weak acids or weak bases may undergo what is

called hydrolysis in aqueous solution, that is to say that

Salt + water = acid + base.

Such an action can easily be shown in the case of
ferric chloride or sodium borate. It was proposed, there-
fore, to classify acids as weaker or stronger accordmg to
the extent to which their salts were " hydrolysed " by
water under similar conditions.

Again, there are many chemical changes which are
found to be greatly accelerated by the presence of acids,
and if these changes happen to be sufficiently slow to
enable one to map out the rate of change, it is possible
to compare the influence of different acids. Results
obtained in such ways agree, on the whole, remarkably
well with the order of "strength" as measured by the
"stri\ing for base " method.

The electric conductivity again was found to be better
for the stronger acid ; and the same is true with regard to
the deviation from the " normal " osmotic pressure abo\e
referred to (Article I.). Such observations were largely
instrumental in leading up to the new theory. If one
" believes in ions,"'^ it is a comparatively simple matter
to explain, in terms of the hypothesis, what is meant
by the " strength " of an acid. The strongest acids, like
nitric and hydrochloric acids, undergo complete, or nearly
complete, ionisation when dissolved in a moderate volume
of water, whereas the weaker acids, like acetic or hydro-
fluoric acids, are ionised to a less extent. In other
words, a moderately diluted solution of hydrochloric acid
contains a (relatively) large number of free hydrogen ions
in a given volume, and an equivalent quantity of acetic
acid contained in the same volume gives rise to (rela-
tively) few free hydrogen ions.

But ionisation increases as dilution increases, so that
we arrive at the conclusion, which sounds paradoxical at

first, that when their aqueous solutions are infinitely
diluted all acids would be equally " strong " \

The strength of an acid, then, depends, according to
these ideas, upon the concentration of the free hydrogen
ions which is attained when an equivalent weight of the
acid is dissolved in water and the solution made up to a
given volume. But how are we going to measure this,
or compare it, say, in the case of two given acids ?

The complete explanation of the way in which this can
be done would perhaps be out of place in a brief sketch
like the present one; we will merely attempt here to give
a very rough indication of the principle.

The electric conductivity of an acid in solution depends
upon the number of free ions present in a given volume
and upon the speed with which they move. If we
determine (directly or indirectly) the molecular con-
ductivity of a given acid (i) when the solution is
moderately dilute, and again (2) when it is infinitely
dilute, it can easily be shown that the first number
divided by the second will tell us the extent to which the
acid is ionised in the moderately dilute solution. We
can then make similar experiments with other acids
under the same conditions, and so compare the extent to
which each is ionised. Assuming for simplicity that
each acid splits up into two ions, one of w hich, of course,
is hydrogen, it is evident that the one which is most
ionised is the strongest under the given conditions, i.e.,
there will be more free hydrogen ions in a given volume
of solution.

The extent of ionisation of the acid can also be arrived
at from other considerations, such as the deviation from
the normal osmotic pressure (see Article I.); but the
electric conductivity method is the most generally applic-
able.

The Problem of Cancer

By Felix Oswald, B.A., B.Sc.

• At the present time il is well to look upon this ionic explana-
tion as a very efficient and complete working hypothesis, and not
to regard it, as is often done, in the light of a creed or dogma.

The failure of bacteriologists to discover a cancer-
bacillus has facilitated future investigation regarding
a probable cure for cancer by narrowing the issue
and disposing of a fruitless line of research. On the
other hand, the recent important discovery of Professor
Farmer and his colleagues, that cancer-cells agree with
reproductive cells in only containing half the number of
chromosomes in the nucleus after nuclear division, re-
calls the experiments of Galeotti,'" in 1693, with regard
to the unsymmetrical and irregular nuclear division in
cancer-cells. It appears probable that the efficacious
preventive treatment of cancer is to be sought in the
direction indicated by these experiments, which have
hardly received the attention they deserve. Briefly
stated, Galeotti treated acti\ely dividing, epithelial cells
of salamanders with dilute solutions of drugs such as
antipyrin, chloral, quinine, cocaine, nicotine, potassium
iodide, &c. The action of these substances caused
asymmetrical and tripolar division of the nucleus,
exactly similar — as the accompanying figures will show
— to the asymmetrical and tripolar division which takes
place in cancer-cells in a human subject. The remark-
able similarity between these pathological occurrences

* Beitr. zur patholog. .\natomie und zur allgem. Pathologie,
XIV. 2 ; Jena, 1S93-

April, 1904.

KNOWLEDGE .^ SCIENTIFIC NEWS.

points to the inevitabu .:: .usion that <a:: ^:
primarily due to an irritant poisonous substance, that
such substance is secreted, in a spot liable to disease,
e.g., in glandular tissue, and that the blood is unable to
carry off or neiitralise the deleterious matter.

The problem of an ultimate cure for cancer would
seem, therefore, to lie in the chemist's sphere rather than
the surireon's, li:.. firstly, in the careful analysis of fresh
cancerous tissue, and the isolation of the irritant prin-
ciple; and, secondly, in thediscoxery of an antidote to be
injected into the system just as antitoxin is injected for
diphtheria, to assist the blood in its function of eliminating
the injurious substance. It is a suggestive fact that antago-
nistic drugs are known to the substances which Galeotti
used in creating the pathological nuclear divisions so

A, — Epithelial Cells of Salamander, showing (i.^ iin.symmetrical
nuclear division after treatment with 0*05 per cent, anti'pyrin solu-
tion; 'ii.) tripolar di\ision after treatment with o'5 percent, potassium
iodide solution. B. — Human Cancer Cells, showing; <i.i unsymmetrical,
and ii.) tripolar nuclear division. [Both after Galeotti

similar to those of cancerous tissue, e.g., strychnine is
antagonistic not only to nicotine, but to chloral, to which
atropine also shows antagonism.

The similarity between cancer-cells and reproductive
cells in containing only half the usual number of chromo-
somes compared to normal somatic cells, and the further
discovery that the nuclei of all the cells in the sexual
generation (prothallus) of a fern show this reduction,
would seem to indicate that the occurrence of cancer-
cells in the bodies of man and higher animals shows a
tendency to a reversion to the remote state of things
when every single cell of the reproductive generation
partook of this peculiarity of the reproductive cell. It
•would be interesting in this respect to ascertain whether
the cells of the sexual generation in lowly creatures of
the animal kingdom, such as liver-flukes, jelly-fish
(Aiirelta), and some Tunicates (Salpa), &c., which exhibit
an alternation of sexual and asexual generations, show
the same condition as the fern prothallus in the vegetable
kingdom.

Rare Living Animals
in London.

By P. L. ScL.\TER, F.R.S.

I \ the annual reports of the Zoological Society of London
will always be found a section containing a list of the
species new to the collection exhibited during the pre-
ceding year, and though, as we all know, it is continually
becoming more difficult to find " something new " in any
class of objects, it will be seen, on reference to the
reports, that even in the most recent years the list of
novelties is by no means a short one. There are, in fact,
always a considerable numlier of recent additions to the
Zoological Society's living collection of mucli interest,
and well worthy of representation by the facile fingers of
the artist, which we believe to be a much more generally
effective way of bringing the points of their shape and
structure into notice than the cheaper and more fashion-
,ible photographs of the present day.

It is with great pleasure, therefore, thai 1 ha\e under-
taken to write a few remarks on some of the rare and
interesting animals in the Regent's Park that have lately
formed the subjects of Mr. Goodchild's skilful pencil.

1. The Thylacine.

(Thylaciniis cyiwirphaliis. )

In the late Sir William Flower's excellent " Introduc-
tion to the Study of Mammals " the threefold division of
that order, originally proposed by Blainville, into " Or-
nithodelphia," " Didelphia," and " Monodelphia" is fully
maintained, although, for good reasons, Huxley's change
of these names into " Prototheria," " Metatheria," and
" Eutheria " is adopted, as being " far less open to objec-
tion." The Metatheria, as Flower points out, are repre-
sented in the present epoch by numerous species which
offer considerable dixersities in appearance, in structure
and in habits, although they all agree in many anatomical
and physiological characters which gi\e them an in-
termediate position between the Prototheria and the
Eutheria. The most important of the latter set of
characters is that the young of the Metatheria are brought
forth in a rudimentary condition, and are nourished by
milk injected into their mouths from the maternal
mamma;, to which they are firmly attached for some time
after their birth. During this process the young, in
nearly all cases, are sheltered in an abdominal pouch or
marsupium, whence the Metatheria have received the
more familiar name of " Marsupials."

The Marsupials then, as we will call them, are usually
divided into two sections, the Diprotodonts and the Poly-
protodonts. Of the former of these, which with a few
unimportant exceptions are vegetable feeders, the best
known are the kangaroos of Australia and the adjacent
islands, while of the Polyprotodonts, which are carnivo-
rous and insectivorous, the finest and largest representa-
tive now living on the earth's surface is the Thylacine of
Tasmania, the animal represented in the accompanying
drawing.

On first seeing the Thylacine alive the uninformed
spectator would naturally take it for a dog or a wolf.
And indeed in general external appearance the Thylacine
is excessively like one of these animals, but it is, never-
theless, undoubtedly a Marsupial in every essential part
of its structure, and like most other members of th«5

KNOWLEDGE & vSCIENTIFIC NEWS.

[April, 1904.

Metatherian group carries its new-born young in an
abdominal pouch. It is also at once distinguishable from
a wolf by its long, tapering, and thinly-haired tail, as is
well shown in our picture, and by the curious transverse
stripes on the bark, wliich are very prominent in the
living animal.

The Thylacine is a native of Tasmania, and is not
found in any other part of the world, although in a former
geological epoch an allied form, which has been named
Thylacinus speUnis by Professor Owen, existed in the
adjacent parts of Australia. In Tasmania the Thylacine

is the only specimen of the Thylacine now alive in
P-urope.

The first living Thylacines ever received by the Zoo-
logical Society were a young pair presented by their
Corresponding Member, Mr. Roland Gunn, of Launces-
ton, in 1849. They had been captured in snares on the
upper branches of St. Patrick's River, about thirty miles
N.E. of Launceston, and lived many years in the Regent's
Park. The same generous friend, learning that these
animals were no longer alive, sent a second pair in 1863,
which likewise did well in the Society's Gardens. Thyla-

Tlie Thylacine {Tliyhimiin ninurf-luiliis).

is said to be popularly known as the " tiger " or
" hyaena," from its rapacious habits, but is also often
called, more appropriately, the " Tasmanian wolf."

In former days, when Tasmania was first peopled by
luiropeans, the Thylacine was common in all the rocky
and mountainous districts of the island, and at that time
found an abundant supply of food in the native kangaroos
and bandicoots. But when sheep were introduced into
the Colony, and bred in large numbers, the Thylacine
soon learned to attack the sheepfolds, and consecjuently
became an object of persecution to the Tasmanian shep-
herds, whose fierce hostility has now brought it to the
verge of extinction. Of late years, indeed, very few
living specimens of it have reached Europe, and the
Zoological Society is fortunate in having secured the fine
young male example now figured, which was obtained
by purchase in March, 1902. So far as 1 know, this

cines in captivity are very active in their mo\'ements
when excited, but somewhat nocturnal in their habits.
They are usuall)' fed on nuitton.

>^ "^i -"^ ^^ "^i

Blake's Historica.1 Cha-rts.

Mh. ^\"ILLI.\^r Pii.AKK h.is compiled a series of Historical
Charts, designed to show in a sort of bird's-eye view the
course of Enslish IIistor\- in different year periods. Chart
No. I. gives a general vieu of English History from 1066 to
igoa. Chart No. H., intended to be used with the other
Charts, and a most useful supplement to them, gives contem-
porary European rulers from 1066 to igo2. Succeeding
Charts cover various pliases of English History from the
Roman Dominion in Britain to the reign of Queen Victoria.
The Charts have been very carefully compiled at the cost of
immense labour, and are designed for the use both of students
and teachers.

April, 1904..]

KNOWLEDGE & SCIENTIFIC NEWS.

fir

The Ancestry of the
CaLrnivoraL.

By K. LvnrKKKK.

CoMTAKi;!! with the more advanced types of ungulate, or
hoofed, mammals, such as the horse, the camel, and the
true ruminants, all the Camivora are in many respects
much less specialised animals, more especially as regards
the structure of their limbs. By this I mean that
although all of them are thoroughly adapted to their own
special mode of life, while in many instances they are
some of the most active, most highly organised, and
most intelligent of all animals, yet they depart much less
widely from the primitive type of mammals in general
than is the case with the more specialised ungulates, or
indeed, than ungulates collectively. In none of them
for instance, docs the number of toes on each foot ever
fall below four, while in some cases the typical five digits
are retained in at least one pair of feet. Then again,
although in the members of the cat tribe specialisation is
displayed by the development of sheaths for tlie protec-
tion of the sharp and sickle like claws, the terminal joints
of the toes are always of the primitixe claw-like type
the unguiculate form, as it is termed by naturalists, and
never make any approacli to either nails or hoofs. More-
over, all the Carni\ora are characterised by the absence
of that tendency to a reduction of the number of the
bones in the limbs by the fusion of two together and the
disappearance of others, which, as we ha\e seen, form
sucli striking features in the evolution of the more
specialised t)pes of hoofed animals. .Such consolidations
and reductions in the bony framework are indeed striitly
correlated with and necessary to the develipment of a
small number of hoofs on each foot, and are, therefore,
from the very nature of the case, conspicuous by their
absence in the Carnivora. Indeed, if we except the
frequent disappearance of the collar-bones, or clavicles,
the skeleton shows none of that anialf;atnation or loss
of some of its elenients, coupled with the e.\cessi\e
development of others, which are such noticeable features
in the more specialised ungulates.

Then, again, the teeth of the Carnivora, though ad-
mirably adapted to the special needs of their owners, are
much less widely removed in structure from the primitive,
or generalised, mammalian than are those of the higher
hoofed mammals. The cheek-teeth, for instance, never
display that heightening or broadening of the crown,
coupled with those deep infoldings of the grinding surface,
seen in the molars of the horse and the ox. Moreover,
unlike what so frequently takes place in the ungulates,
the front teeth are always well developed, and rarely fall
below the typical mammalian number of three pairs of
incisors and one of canines, or tusks, in each jaw. In-
deed, when a reduction in the number of the teeth does
take place, as in the cats, whose short jaws do not leave
room for the full complement, such reduction takes place
at the hind end of the series.

Among living Carnivora the group which is in the
whole the most generalised and the least widely removed
from the primitive ancestral type is that of the dogs —
including under this name not only the animals properly
so called, but likewise wolves, jackals, foxes, etc. To
enter into a consideration of the structure of the skeleton
would obviously be an impossibiliiy on this occasion, and
it must accordingly suffice to mention that while thetypical
number of five toes are retained in the fore-foot of nearly
all members of the group, in the hind foot there are only

four ; and that although collar-bones arc developed, yet
they are reduced to mere rudiments. One other impor-
tant circumstance in coniU'Vj^u-^wilii i'kirJi^rt'-^^ iiiusl,
however, be noticed. If tno ikjVu"^ (TT Uu; wnsfTor car-
pus, of a dog be compared wYl'l^'^Wifr? ^ mau or of

;h:fr'^u;;;:r^r::::«sSK>^^

elements. This is due to tTie fusion of iwi of the bones,
the scaphoid and lunar ; dKP tAiki)iHid£)^clI^Jhtliteristic
of all modern Carnivora, in which the coni])nund bone is
known as the scapho-lunar.

One other feature — and this connected with the denti-
tion— is very characteristic of modern land Carnivora.
In the skull of a cat, dog, or wolf (fig. 1 ) it is well known
that one pair of teeth in the side of ea( ii jaw dilier
markedly in size and structure from all the rest, the upper
biting upon the lower pair with a more or less scissor-
like action. It is with this pair of specialised teeth that
a tiger or a lion cuts up the masses of flesh torn from its
prey into convenient lengths for swallowing ; and these
formidable weapons are consequently known as the car-
nassial, or flesh, teeth. Curiously enough, these teeth
do not serially correspond with one another. It will be
seen, for instance, both in fitfure i ;in(l fi<rure 2, that while

r^^

K^H##fV-

Fig.

-5ide view o( skull of Wolfto show the carnassial teelh.

the upper carnassial is the fourth from the tusk, the cor-
responding lower tooth is the fifth from the latter; liotli
the species in the two illustrations referred to ha\-ing the
full typical series of anterior cheek-teeth. Nor ir, this all,
for whereas the upper carnassial has no deciduous pre-
decessor (" baby-tooth "), the corresponding lower tooth
succeeds a deciduous baby- tooth. Conscrjuently, the
upper carnassial — to employ technical language- belongs
to the premolar series, while the lower carnassial is one
of the true molars.

Now, when we find two organs which do not serially
correspond with one anotlier, modified for some particular
function, it may be at once taken for granted that this is
a highly specialised condition which did not obtain in
the beginning ; and this we shall find to hold good in the
case of the (Carnivora.

hVom the general presence of this peculiar type of den-
tition, all the modern Carnivora, together with many of
their extinct relatives, are collectively known as theCar-
nassidentia. Not that it must be assumed that this
feature is common to them all. In the bears, for in-
stance, the carnassials, although still displaying traces of
the characteristic structure, have become comparatively
small and weak teeth, much smaller than the grinding
molars behind. And this degeneration (for by means of
fossil forms the feeble carnassials of the bears can be traced

KNOWLEDGE & SCIENTIFIC NEWS.

April, 1904.

into the fully-developed ones of the dogs) may be
explained by the nature of the food of bears, which does
not require the action of scissor-like teeth.

.\t(ain, in the seals and walruses there is no trace of a
differentiated pair of carnassial teeth ; such a type of
dentition being unnecessary to animals living on a fish
diet. In the case of the eared seals and walruses, there
is little doubt that the absence of differentiated carnas-
sials is due to degeneration, these creatures being
apparently related to the bears. The case of the true, or
earless, seals is more uncertain : and it has been sug-
gested that these creatures inherit their distinctive type
of dentition direct from an extinct group referred to
below. .Vgainst this is the circumstance that they
possess the compound semilunar bone in the wrist, which,
on the above view, would imply the fusion of the two
elements entering into its composition in two independent
instances.

Reverting to the existing members of the dog tribe, it
will be noticed that the skull (fig. i) is characterised by
its elongated form and relatively large brain-cavity. The
teeth fall short of the typical mammalian number of 44
only by a single pair — namely, the last pair of molars in
the upper jaw. Consequently there are only two pairs
of teeth behind the upper carnassial. In the lower jaw
the last molar is \ery small, and evidently on the point
of disappearance. As regards the other teeth, it must
suffice to mention that the carnassials are strongly de-
veloped and possess a perfect shearing action, the lower
one having a large tubercular portion for masticating
behind the cutting blade ; and that most of the premolars
(other than the upper carnassial) carry accessory cusps
on either side of the main cone. It may be added that
all the existing members of the fatnily are digitigrade —
that is to say, they walk on their toes instead of on the
sole of the foot, which is raised above the ground and
covered with hair.

A large number of extinct dog-like animals have left
their remains in the Tertiary strata of both Europe and
North America ; those from the newer formations being
nearly allied to existing types, while the older forms are
more or less decidedly different. One of the most im-
portant of these extinct types is the Oligocene and
Miocene genus Cynodictis, which is without much doubt
the ancestral type of the true dogs (diiiis) of the present
day. Although generally having the same dental formula
as the latter, Cynodictis exhibits distinct signs of affinity
with the ancestors of the civets. On somewhat the same
platform of evolution as Cynodictis is the North American
Daphanus, of which the skull is shown in fig. 2. In this
animal it will be seen that a small third upper molar
(the third tooth behind the carnassial) is retained, thus

bringing up the number of the teeth to the typical 44.
In general characters, the dentition is very similar
to that of modern dogs, but there are fewer accessory
cusps to the premolars, and the posterior portion of the
lower carnassial is adapted for cutting, instead of for
grinding. The dogs of this genus are further remarkable
for the shortness of their JAws ; and it has accordingly
been thought that they may ha\-e been the ancestors of
the modern wild dogs (Cyon) of Asia.

Great interest attaches to another type of Tertiary dog,
the A inpliicyon of the Miocene and Oligocene strata of both
hemispheres, some of the species of which attained
dimensions rivalling those of a bear. This interest is
due to the fact that these giant dogs, which had 44 teeth,
and partially plantigrade feet, were the actual ancestors
of the modern bears, with which they are connected by
certain extinct genera. We thus establish the derivation
of bears from dogs of a generalised type.

All the foregoing extinct general types of dogs may,
however, themselves be apparently derived from a still more
generalised form from the Middle, or Bridger, Eocene of
North .'\merica, known as Vulpavus. In this animal,
wnich can only be tentatively included in the dog family,
the skull (fig. 3) is characterised by its long and narrow

Fiit. 2.— Skull of iMiili.Tiuit, a primitive Dog from the Middle Eocene
strata of the United 5tate.s, with a crown view of first and second
lower molars. 'After Dr. Wortman.)

Fig. 3.— Skull of Vulpai'ui, an ancestral type of Dog from the
Bridger Eocene. (After Wortman.)

form, and the small size of the brain-cavity. The teeth,
of which there are 44, are of a decidedly dog-like type, but
the outer front angles of the upper molars assume a cutting
character, and the bkide of the lower carnassial is much
taller and narrower, and also more obliquely placed,
than in the dogs, while the second and third lower
molars, although much smaller, present a decided re-
semblance to the carnassial. Moreover, the lower pre-
molars have large fore-and-aft cusps, differing in character
from those of the true dogs. Unfortunately, the struc-
ture of the wrist is unknown, but it is quite possible the
scaphoid and lunar bones may be separate. The hind
as well as the fore feet were five-toed.

More or less nearly allied to Vulpavus are certain other
Lower Tertiary Carnivora, exemplified by the genus
Vivevravus, which are regarded as forming the most
primitive family of Carnassidents at present known.
They have five-toed feet, with the scaphoid and lunar
of the carpus separate; and the dentition, in which the
number of the teeth may be either 44 or 40, difters
from that of Vulpavus by minute details, to which it is
impossible to refer on this occasion. In certain numbers
of the family, such as Oijdectes, the last two lower
molars are exceedingly like the carnassial, and have
their crowns but little lower, although these teeth retain
the essential carnassident feature of being smaller than
the latter. In other respects, the dentition of these
primitive forms comes very close to that of the under-
mentioned creodonts, with which the Viverravida also

April, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

agree in their divided scaphoid and lunar. As indi-
cated by the name of the typical ijcnus, the ]'ii(ii(iviJu-
are re,t;arJed by .\nierican pala-ontoloi^ists as the ances-
tors of the ci\ets (r/rvM/iL-) of the old world; and it is
not improbable that they were likewise ancestral to the
primitive dogs. If it be added that there is evidence to
show that the members of the weasel tribe are also
sprung from a more or less nearly allied Eocene group,
we shall have accounted for the origin of four of the
most important families of existing land Carnivora,
namely dogs, bears, civets, and weasels. As regards
hya?nas, there is little doubt that they are closely related
to civets, with which they appear to be connected by a
number of extinct forms, such as IitHI:eiiiiw.

Leaving the raccoon family alone, it may be added
that there is still some degree of uncertainty with regard
to the origin of the cats (Felida-). Unless, l)owe\ er, they
trace their origin direct to the undermentioned creoclonts,
there seems to be considerable probability that they
are derived from the imperfectly known family of primi-
tive camassidents termed PaLconklidte, all the members
of which are characterised by their short jaws and cat-like
dentition. In the typical Palteonictis, which dates from the
\\"asatch, or Lower, Eocene, the carnassials are somewhat
imperfectly differentiated from the other teeth ; but in
.Ulurotherium of the Bridger they become well characterised

Having thus traced, more or less definitely, most of
the principal families of existing land Carnivora to
generalised forms which are evidently on the bordeiland
between the Carnassidentia and some more primitive
type of Carnivora, we have to turn our attention to what
is known with regard to the latter.

WU*V^

Fig. 4.— 5kull of Sinop.:, a North American Creodont. (After Wortman.)

Such primitive type is represented by the Eocene and
Oligocene Carnivora collectively known as Crecdontia,
of which the American'5(H(?/'a or Stypolophus" (fig. 4) and
the European Hycenodon and Pterodon (fig. 5) are well-
known representatives. In addition to other features
which cannot be noted here, these creodonts are collec-
tively characterised by three long, narrow, small-brained
skulls, by the fact that the scaphoid and lunar of the
wrist are usually distinct, and, above all, by the non-
development of a pair of differentiated carnassial teeth.
In place of these, the lower jaw (fig. 5) has all the three
molars of a cutting type ()«', )«-', w;^) ; and it will be
further noticed that these teeth differ from the corre-
sponding teeth of a carnassident by the circumstance
that they increase in size from the first to the third,
instead of decreasing. These animals all have five- toed
feet, in which the thumb and the first toe may he
opposable to the other digits.

Unless these creodonts have given rise to the true seals
of the present day, they seem all to have died out during
the Tertiary period without leaving any descendants.
Moreover, they appear to have been derived from some
still more primitive stock independently of the carnas-

* Represented in Europe by ihe closely allied Cynohyctnodon.

sidents, with the earlier forms of which latter they were,
however, evidently allied. In other words, camassidents
and creodonts appear to be (h\eri;ing branches from a
single primitive stock-, which proh.ibiy li\t\l iluring the
Secondary, or Mesozoic, epoch.

^'^k: AJ;:-d'%f

FiK. ;;.•

-Lower Jaws of Creodonts and Marsupials.

2 PtfTudon, 3 H(trU;i'i lift, 4 TiiijlacintiH.

What were these Mesozoic ancestors, is the next ques-
tion which presents itself.

.V comparison of the lower javvs of the creodont
Hyctnodon and Pterodon with that of the marsupial 1 hyla-
cinus, as displayed in fig. 5, shows at a glance that the
dentition in all three is of the same generalised type ;
this being especially indicated by the form and relative
dimensions of the three molars. It is true, indeed, that
in the marsupial there appear to be four of these teeth ;
but this is due to the fact that the tooth in advance of
these (m.p. 4) is a persistent milk-tooth, which is not
replaced, as in the creodonts, by a permanent premolar
(pp. 4). Certain South American extinct types such as
Borhyana (fig. 5 — 3) are intermediate in regard to the
number of teeth replaced between creodonts and mar-
supials, in Iho latter of which only one (pp. 3) is so
changed, and it is consequently a difficult (juestion to say
whether these South American forms .should be classed
as creodonts or marsupials.

Be this as it may, it is (juite evident that creodonts
and marsupials are nearly related, and have probably
both sprung from Mesozoic ancestors. The next ques-
tion is whether these Mesozoic ancestors should be
called creodonts or (in a wide sense) marsupials. Un-
fortunately the degree of preservation of the compara-
tively few and imperfect known remains is such as to
preclude a definite answer being given to the ques-
tion. Dr. Wortman, to whose opinion I attach great
value, inclines to the belief that they were marsupials.
Personally, basing my opinion on the restricted tooth-

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

change of the latter, I am more disposed to call the
Mesozoic forms primitive creodonts, and to consider
creodonts as the ancestors of marsupials, rather than
vice vena.

The whole question is, however, absolutely bristlint;
with difficulties and uncertainties, and involves the dis-
cussion of a number of technicalities which cannot
possibly be touched upon here.

With this, then, I must lea\e the subject, merely
adding that after having traced the specialised modern
Carnivora into early types closely allied to the primitive
Creodontia, and ha\ing also pointed out the existence of
a near affinity between the latter and the carnivorous
marsupialia, the question naturally arises whether the
middle Mesozoic mammalian forerunners of these groups
may not themselves be the descendants of the carnivor-
ous mammal-like reptiles (theriodonts) of the early part
of the same epoch, which have a typical carni\orous
type of dentition. If so, the dog and civets of our own
day have a truly ancient pedigree.

Is there Snow on the
Moon ?

A Study of the Lunar Apervrvirves.

I5v E. Walter MArxL.F.R, F.R.A.S.

Tin: principal object in the accompanying Plate, which is
reproduced from one of the superb photographs taken by
MM. Loewy and Puiseux, with the great equatorial
coude of the Paris Observatorj', is the range of the
lunar Apennmes, by far the grandest mountain
chain upon the moon, and the one which, at first
sight at least, most stronLrly resem-
bles those of our own earth. It is
shown in its entire length of more
than 400 miles from the fine ring-
plain Eratosthenes, in the extreme
right-hand upper corner of the
Plate, which forms the termination
of the range to the south, down to
the grand promontory of Mount
Hadley, more than 15,000 feet in
height, in which it ends towards
the north. About halfway between
the two extremities of the range is
the magnificent headland of Mount
lluyghens, according to Schmter
nearly 21,000 feet in height, the
highest summit on the moon with
the exception of some of the peaks
on the ramparts of the ring-plains
of the south polar cap. A third
great promontory. Mount Bradley,
lies nearly midway between Mount
Huyghens and Mount Iladley and
reaches a height of about 16,000 ft.
The highland region, of which
the Apennines form the north-
eastern face, is roughly triangular
in shape. By far the loftiest and
steepest face is that overlooking the

great Mare Imbrium towards the east. The north-west-
ern face looks over the Mare Serenitatis, whilst the Sinus
.■Estuum and the Mare \'aporum bound the region on
the south.

The area of the Plate is not one which includesm any
of the circular formations so typical of the moon, but
some of those which are shown are very striking. Three
great ring-plains are seen on the floor of the Mare Imbrium.
These, in order of size, are Archimedes, the largest and
most eastern, Aristilles, the most northern, and Autoly-
cus, the smallest of the three, just opposite the broad
gap which separates the Apennines from the Caucasus.
On the opposite side of this opening, and slightly further
from it, the celebrated crater Linne is seen as a small
white spot on the floor of the Mare Serenitatis. Toward
the extreme upper left-hand corner of the Plate, near the
border of the same Mare, stands the bright crater Sul-
picius Gallus, and amongst the actual highlands of the
Apennines are the two craters Conon, just behind Mount
Bradley, and Aratus, a little further north towards Mount
Hadley. These seven are the most notable circular
formations in the Plate. In general, the lunar mountains
take the form of rings or polygons, as in the case of these
se\en objects, and do not make continuous chains as on
the earth. To this rule the Apennines constitute the
most conspicuous exception, but a detailed exanrination
of them shows that the differences between them and
the great terrestrial ranges are numerous and significant.

The first feature of the Apennine highlands to claim
attention is the nearly triangular form of the area they
cover. This is a necessary consequence of the roughly
circular form of the great Maria which border them.
Wherever we have a number of circular depressions con-
tiguous to each other, the more elevated interstices must
necessarily approximate to triangles. .And this being the
case, it follows that the forms of the highlands ha\'e been
determined by the Maria and not the reverse. In other
words, the highlands existed first and acquired their
present outlines through the later formation of the
surroundinij Maria.

Ma rr
■ Ji'rriii/aiis

Arc/ianedes

Jristilles

'KxowLKPi-.E A Scientific News." — .-Ifi.'.', />«'/.

I-
O

■1S3M

Aprii , 1904 ]

KNOWLEDGE & SCIENTIFIC NEWS.

r.^

The next feature to be noticed is the general slope of
the repon. Towards the Mare Iinhriiun on the cast,
the face presented by the Apennines is exceedingly bold
and steep; towards the Mare Serenitatis an<l Mare
\'ap)orum on the west and south the highlands sink
down iiradmllv.

Pijf. I.— Morning.

The result of such a formation upon the earth would
be obvious. There would be a deposition of moisture
over the whole highland region, either in the form of
snow or water, and this moisture would move downwards
towards the plains either as streams or glaciers. lUit it
would move with very different speed and different effects
upon the two faces. On the steep escarpment facing east

Fijf. 2. — Forenoon.

neither water, snow, nor ice could rest. The moisture
would be quickly thrown off, descending in waterfalls or
avalanches down to the plains, and wearing away the
cliff face into a great number of narrow gorges or gullies.
The liebris would be deposited at the foot of the cliffs,
and the torrents would car\e their way some distance
into the plain, as a rule in a direction at right angles to

the range, smoothing out and covering all irregularities
which ran parallel thereto. What we actually see upon
the photograph is as unlike this as could well be imagined.
The liase of the range in the Mare Imbrium is confronted
by a line of low hills, wrinkles as it were on the surface
of the plain, suggesting by their parallelism to the range

rijf. .?. Noon. J

that no effecti\e amount of moisture, either as rain or
snow, had been deposited on the eastern slopes nf the
Apennines since the Mare Imbrium was formed.

r)iit the main drainage of the region would be in the
opposite direction, because the chief catchment area would
be the broad gentle slope towards the west and south.
Here the tendeury would lie for the moisture, whether it

ri^. 4.— AUf rnoon.

was in the form of ice or water, to unite small streams
together to form larger ones. Important risers or glaciers
would have their origin in this region, and would work
their way downwards excavating broad valleys. The
erosive effects, if not so rapid as on the east face, would,
from the better presentment to us, be even more con-
spicuous, and there should be no difficulty in detecting

KNOWLEDGE & SCIENTIFIC NEWS

'April,

1904.

the deposit of alluvium at the mouths of the great water-
courses. We do indeed find valleys and ra\ines on the
western slopes, but these often are so blocked or show so
many irregularities of level that they cannot be held to
be water channels. If this was their original nature, then
the more recent history of the moon must have entirely
changed their appearance ; we see nothing to remind us
of the characteristic arrangement of a drainage area on
the earth. More than that, we find in the neighbourhood
of Sulpicius Gallus a dark band parallel to the edge of
the Mare Serenitatis, as if the Mare w-as actually deeper
here than further out in the plain. Such a channel would
have inevitably been filled up by the alluvium washed
down by rivers draining the highland district.

It is very instructive to watch the apparent changes
produced in any region of the moon by the progress of
the lunar day. The fi\e photographs of the regions of
the Apennines shown in figs. 1-5 are reproduced from
Professor W. H. Pickering's " Photographic Atlas of the
Moon," noticed in the last number of " Knowledge,"
and will give some idea of the great value of this syste-
matic mode of study which Professor Pickering has

F'g.-5- — Evenin;?.

carried out. It will be seen at once that the change in
the lighting produces an immense change in the general
appearance of the region. The five photographs we may
describe for purposes of reference as showing the district
at morning, forenoon, noon, afternoon, and evening ;
descriptions which are only roughly correct, but which
will suffice for reference. It will be seen at once that the
appearance of relief vanishes almost entirely at noonday ;
it increases directly in proportion to the obliqueness of
the illumination, and is very marked in the last photo-
graph of the series taken almost at sunset. The two
great craters, Archimedes and Eratosthenes, are prac-
tically lost at noon. At this time the brightest objects
are the glittering peaks of the Apennine range, the rampart
of Conon, and the white mantle surrounding Aratus.
In early morning and late evening the gradual slopes of
the highlands towards the west, and their steep declivi-
ties towards the east, are the regions which respectively
shine out most conspicuously. But it is the latter which
are by far the most brilliant ; and, looking at the fifth
photograph, there would seem not a little to justify Pro-
fessor W. H. Pickering's description of them as snow
covered. " Many of the higher summits of the Apen-
nines," he writes, " are brilliant with snow, although the

sun is just setting upon them, whilst the slopes of the
intermediate valleys and of the foothills are dark."

Professor Pickering's interpretation of the brilliancy of
the eastern slopes of the Apennines involves several
assumptions. He considers that the deposition of snow
will vary on the moon according to the elevation of a
district and according to its distance from the equator.
But it should be borne in mind that elevation on the
moon will not be nearly as effective in producing con-
densation as on the earth. The action of gravity at the
lunar surface is but one-sixth of what it is with us. This
would have a two-fold effect. Whilst here w-e reach a
region of half the surface pressure at a distance of three
and a half miles, on the moon we should have to ascend
more than twenty-one miles to obtain the same pro-
portional diminution, whilst the feebleness of gravity
would make any upward motion of the atmosphere ex-
ceedingly slow. The cooling of an ascending current of
air by expansion, here the most efficient cause of con-
densation, would there be practically inoperative, and the
great tenuity of the lunar atmosphere would tend in the
same direction. There would scarcely be any perceptible
difference in the readiness with which condensation
would take place between the plains and the mountain
summits.

The comparison of the five pictures, too, does not sup-
port the inference that the bright regions are snow-
covered. The western gentle slopes are by no means so
bright under their best illumination as the steep eastern
escarpments are under theirs. Yet it is on the former that
we should expect the snow to lie, whilst as they are best
lighted by the morning sun, that is to say, just as they
emerge from the long lunar night when the snow should
be thickest, we should expect them to be far more fully
covered, and therefore more brilliant than the steep
eastern slopes could be at sunset, after having undergone
the continued action of the sun during the whole length of
the lunar day. The changes in illumination are indeed
just what w-e might expect from the varying incidence of
the solar rays, provided that there was some difference in
the reflective power of the different surfaces. And in
this case there is no difficulty in pointing out a sufficient
cause for the steep slopes being more brilliant than the
gentle. Mr. Davison (" Knowledge," December, i8g6,
p. 278) pointed out that objects on a slope from, the mere
effect of the expansion during the heat of the day and
contraction under the cold of night, would steadily creep
downwards. There would thus be a very slow but con-
tinuous transference of free solid particles from the
summits of the mountains towards the plains, uncovering
fresh surfaces in the higher regions, and this creeping
effect would necessarily be much more rapid on such
steep declivities as the eastern face of the Apennines
than on the gradual slopes towards the west. If then
the very tenuous atmosphere which we may readily
believe to exist upon the moon be capable of effecting
some slight tarnishing or darkening effect in the course
of centuries, or if the deposition of meteoric dust, which
must be much the same as upon our earth, slowly coats
our satellite with a thin dark veil, we shall find a sufficient
explanation for the difference in albedo of the mountain
peaks and of the great plains.

This explanation is emphasised by the consideration
of a point which Professor Pickering brings forward in
proof of the existence of snow deposit. He points out

• I use the terms "east" and " west" throughout this paper,
from our point of view. An inhabitant of the moon would, of
course, regard the slopes facing the sunset as the western slopes.

April, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

that though the central regions of the disc are as " rough
and mountainous as that near the pole " they are very much
darker. It is hardly the fact that the equatorial regions
are as rugged as those of the North Pole, hut when we
compare the equatorial regions with the polar under the
same conditions of foreshortening as well as of illumination
the latter have no evident superiority in brightness. It
is abundantly clear why the regions near the edge of the
disc, whether polar or equatorial, appear the brightest,
for it is just here that the darker valleys are concealed
from us and that the steep mountain slopes are presented
to the fullest advantage.

The question as to whether there are anywhere upon
.the moon deposits of snow is too large a one to be settled
by an appeal to the evidence which even so grand and
extensive a formation as the Apennines and their high-
lands can afTord, but so far as they are concerned the
verdict would clearly seem to be in the negative. It must
always be difficult to distinguish upon the moon betw^een
changes which are simply due to changed illumination,
and therefore which are apparent only, and changes
which are real but are strictly seasonal, for the period of
both will be the same. But in this particular region both
theory and observation seem to unite in discountenancing
the idea of snowfall and in ascribing the apparent changes
in the brightness of the Apennine highlands purely to
the varying incidence of light on surfaces of different
reflective power.

The CaLrvQLls of Ma^rs.

By \V. F. Denning, F.R.A.S.

Recent observations and discussions in reference to the
canals of Mars have been very important and will be
the means of clearing up doubtful points and putting our
knowledge of the planet's surface configuration on a well-
assured basis. The fact that many of the spots on I\Iars
represent real features give them a special interest, for the
other large planets of our system appear to be too densely
involved in atmospheres to exhibit the material conforma-
tion of their globes.

Schiaparelli discovered the canaliform aspect of ;\lars
in 1877, and the general correctness of the Italian astro-
nomer's work has been affirmed by many of the leading
planetary observers in subsequent years. But the path
of the pioneer is difficult and apt to carry one a little
astray through its general direction may be accurate
enough, Schiaparelli has not been successfully followed
in all the details included in his charts of Martian topo-
graphy, nor has the doubling of many of the canals been
corroborated. But apart from the latter peculiarity his
delineations form the best working basis for present
observers, and carry us tar beyond the charts of Green,
whose well-executed drawings are marred by the fact
that he was over-scrupulous as to the insertion of details
not prominently distinguishable.

Schiaparelli has no doubt delineated the canals undei
aspects too straight, hard, and uniform. P'or the most
part the telescope displays them as really faint pencil-
like streaks or veins, knotted with darker regions and
by no means of equable width or even tone. Though
classed under one name and drawn in a uniform way
they certainly represent very dissimilar objects.

Some of the canals are due to contrast, and r-
apply to the boundaries between dusky areas toned a
little more deeply than the outlying parts of tlie ruddy
surface.

Others are pretty consistent with their title, being

formed of streaks apparently connectin , i%nown

spots, and sometimes meandering over extensive tracks
of the surface.

Others again are composed of small irregular con-
densations, lying approximately in rows and roughly
blended together under the aspect of bands in which
much detail may be momentarily glimpsed. With ordi-
nary telescopic power, however, tlieir general appearance
on the small disc is that of streaks or canals, and tiie
observer (igures them as such, being unable to satisfac-
torily define their structure in detail.

In Marcii, 1903, I i)egan a series of careful observa-
tions of Mars with a lo-inch reflector. I'avourahle
weather during tlie ensuing two months enabled me to
examine the planet on 26 nights, when 36 drawings were
made. On the first few nights 1 detected some of the
canals under absolutely certain characters. .\ consider-
able number of those shown in Schiaparelli's charts were
identified, and the result of my scrutiny was to prove the
general correctness of his drawings. Hut I utterly failed
to recognize the supposed double canals. To my eye,
the lines were invariably single under the highest powers
I could effectively apply, and I am bound to conclude
that the gemination is not a real feature.

Mars in the Spring of 1003. LonifUude, 2O5 .
io°inch Kefltctor. Powers, 312 and 375.

During my observations several striking changes were
remarked in prominent objects, and these were probably
occasioned l)y atmospheric movements on tl^e surface of the
planet. The presence of clouds or obscuring vapours
must, however, havealTected relatively small regions, for the
markings were usually visible from night to night under
similar aspects, allowance being made for the variable
definition.

The white spots formed striking features, and especially
so when on or near the edge of the disc. They appeared
to be equally as permanent as the dark markings.

From observed transits of the Syrtis Major, compared
vith some I obtained with a 4y-in. refractor in February,
. ^69, I determined the rotation period as 24h. 37m. 22-7S.
from 12,135 rotations.

There are really many distinctions in the canal-like

markings ; some of them are quite broad and diffused

hadings, while others are narrow-, delicate lines. The

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

dusky knots (called Oases by Lowell, who claims to have
discovered them) were distinctly seen here in 1S84, 1886,
and other years. In Natuvc for June 3, 1886, I refer to
the canals as •' linear shadings with evident gradations in
tone and irregularities occasioning breaks and condensa-
tions here and there."

The ingenious experiments conducted by Messrs.
Maunder and Evans {Montlily Notiiis, June, 1903) e.xplain
some of the observational results without throwing doubt
on the whole canal-system of Mars, as some readers have
supposed. Certain of the canals are indeed so conspi-
cuous as to form objective features comparable in point
of distinctness and certainty with the dark belts of [upiter
and Saturn.

If we could greatly enhance telescopic power and
examine Mars under a sufficiently amplified disc, the
canals would probably look very different to those shown
in the miniature views supplied in ordijiary instruments.
We should see them as large blotchy bands of dusky
material having no resemblance whatever to sharply-cut
waterways. The south equatorial belt of Jupiter consists
of a series of spots, and it presents a curious transforma-
tion under magnifying powers of 50 and 300. With the
former it forms a \ery dark narrow streak, but with the
latter it is broken up into masses of flocculent material
covering an extensive track.

If the existence of the Martian canals has been doubted,
it is partly the fault of certain observers who ha\e greatly
multiplied the real number of these objects, drawn them
under unnatural aspects, and elaborated the general
appearance of Mars in a manner palpably inconsistent
with telescopic revelations.

Mr. Story remarks that " it is time an end should be put
to the inquisitorial fashion of refusing credence to scientific
discoveries." It is true that certain forms of criticism
merely harass and embarrass observers, without effecting
any useful purpose. On the other hand, we cannot unre-
servedly accept everything offered us in the way of
observation, real and \isionary, objective and subjecti\e.
Astronomical history would form a curious medley of
fact and fiction (chietiy the latter) if all the supposed
" disco\eries" of past years were credited and reiterated.
Criticism has occasionally proved a wholesome and
necessary corrective to results of abnormal and unsup-
ported character.

Conflicting testimony in planetary observation is usually
attributed to the differences in telescopes, eyesight, and
local atmospheric conditions. But the more potent cause
is to be traced to the observers themseKes, who differ
widely in their discretion, judgment, and interpretations.
One man will accept and possibly elaborate extremely
delicate features very imperfectly and uncertainly glim psed.
Another will absolutely reject similar appearances. Two
things conae actuely into play and are directly opposed,
viz.: (i) The dominating deaire to glimpse novelties and
gain repute by eclipsing past records ; and (2) the
necessity of accepting only what is certainly and steadily
seen to the exclusion of all doubtful features. On these
points obser\ ers differ vastly ; some of them do not
sufficiently realise their responsible positions, and hurriedly
make records not justified by telescopic evidence; others
are perhaps too punctilious and apt to reject details which
are real, though only faintly and fitfully glimpsed.

In judging the quality of results it should be remem-
bered, as a most important factor, that the individual
characteristics of the observer play a very prominent
part. Some people possess the faculty of seeing objects
double. (Jthers will invariably discern novelties where
none are visible. Others, again, will detect canals as a
necessary feature of a planetary disc. Thus Mercury and

Venus have been supposed to display these markings very
conspicuously. Phenomenal vision will not explain the
anomalies alluded to. Objective markings are capable of
being corroborated without any difficulty. The spots on
Saturn were distinguished by many observers shortly
after their discovery. There is no reason why canals
should prominently diversify IMercury and \'enus as seen
by one observer, while as viewed by others the discs of
those planets appear, under the best circumstances, abso-
lutely free from such markings. On many occasions during
the last few years the beautifully defined disc of Venus
has been examined by the writer, but not the v^estige of
a canal has ever revealed itself; yet at the Lowell Obser-
vatory, Mexico, " the markings are perfectly distinct and
unmistakable, invariably visible, and nothing but a very
unsteady air can obliterate them " [Montlily Notices,
Vol. L\TI. 1896-7, pp. 149 and 402).

Flammarion was probably quite correct in his expres-
sion (" Knowledge," November, 1897) that " the maps
of Venus made up to the present time are illusions."

But our present concern is with l\Iars. The story of
his canal-like markings is a true one, though it has been
occasionally exaggerated, and it will survive all the oppo-
sition levelled against it by sceptics and incapable ob-
servers. The northern hemisphere of the planet seems
replete with dusky streaks forming the canals. They
may not indicate water courses, and their real aspect may
be something very dissimilar to that displayed in ordinary
telescopes, but with the means employed observers are
correct in representing many of them as lines and bands
of shading connecting the more bulky spots.

The Spinthariscope.

The ingenious mstrument to which Sir William Crookes
gave the name of the Spinthariscope, and which he de-
vised to show the torrent of rays or the fragments of
atoms which are continually being shot out from radium,
is now a familiar object to most scientific people. The
instrument as is well known consists of a little screen of
zinc sulphide or blende, at a slight distance from which
a fragment of radium bromide is situated on a pointer.
,\s the emanations from the radium strike the screen
they produce an effect similar to that which a bullet pro-
duces when it strikes a target, and by means of a magni-
fying glass the phenomenon is rendered clearly visible.
The instrument is now made by Messrs. A. C. Cossor,
and one of them which has been sent to us shows the
scintillation with remarkable clearness and \i\idness.
It is, perhaps, the most ingenious, and certainly
the most lasting, scientific toy that ever has been
produced.

Some time a^o, in a lecture to the Camera Club, Mr. Duncan
deitroyed the poetic belief, relating to the nautilus, which is
expressed in Popes lines:

" Learn of the little nautilus to sail,

Spread tliine oar and catch the driving gale " —
bv remarking that the little sails which the nautilus was popularly
and poetically supposed to spread were, in fact, never raised at all,
but were always tightly clasped about the shell. In a paper con-
tributed to the Xatuittl History Miigit::inc. Captain Barrett Hamilton
disturbs an idea relating to the wings of the flying fish that is at
least ecjually widespread. In the true frying fish Captain Hamilton
says the " wings " are never moved as organs of flight. They may
vibrate or quiver under the action of air currents, or a shifting a
little of their inclination by the fish, but the whole motive power
is supplied by the powerful tail. The wings are a parachute to
augment the action of this propeller. Their motions are in no way
comparable to those of the v.ings of a bird.

April, 1904.]

KNOWLEDGE cS: SCIEXTIEIC NEWS.

The Face of the Sky for
April.

By W. SiiACKLETON, F.K.A.S.

The Si'N. — On the ist the Sun rises at 5.3S, and sets
at 6.31 ; on the joth he rises at 4.37, and sets at 7. ly.

The equation of time is negligible on the 15th and
i6th, hence these are convenient days for the adjiistniont
of sun dials or for laying down a meridian line to a close
approximation.

SunsjXits are of frequent occurrence ; their positions
may be located by the use of the following table : —

Date.

Axis inclined to W. from
N. point.

Centre of disc, S of
Sun's equator.

\pril 5 ••
.. 15 ••
.. 25 ..

26" 29'
20° 14'
25" 14'

6° 111
5° 27'
4° 34'

The Moon : —

Date.

Phases.

April 7 . .
.. 15 ••
.. 23 ..
., 29 ..

(T Last Quarter

• New Sloon

]) First Quarter

O Full Moon

H. M.

5 .53 P-m-

9 53P-m

4 55 a.m.

10 36 p.m.

Occulta.tions.

The following are the principal occultations visible at
Greenwich at convenient times : —

Saturn is a morning star, rising at 3.15 a.m. near the
middle of the month ; he is situated in Capricormis, and
conseciuently low down in the sky.

I'ranus rises on the isl alunit 1.30 a.m., ami on the
30th at 11.30 p.m.; througlioul llie month the pi. met is
close to 4 Sagitlarii, Ix-iiig only si.\ minutes wt-st anil
having approximately the same declination as the star.

Neptune is getting more to the west, and sets about
.S.30 p.m. near the middle of the month. He is describ-
mg a retrograde path towards >; Geminorum ; his posi-
tion with respect to that star may be seen on reference to
the chart given in the January number.

IMeteor SiiowiiKs : — ■

Radiant.

Character-
istics.

Dale.

R.A.

Dec.

Name.

h. m.

Apr.ij-May i

16 0

+ 47°

T IlFrculids

Small , short

,, 20-2I

17 20

4- 30'^

TT 1 lerculids

Swift; 111. white

,, 20-2J

IS .,

+ ii'

Lyrid Shower Swifi

.. 30

icj 24

+ 59"

0 Oraconids

liather slow.

The Sr.\RS. — About the middle of the month at 9 p.m.
thepositionsof the principal constellations are as follows:
Zenith . Ursa Majur.
North . I'nlaiis : to the right, Ursa Minor and

Draco; to the left, Cassinpeire and I'crseus ;

below, Cepheus and Cygnus.
South . Leo and Hydra; to the south-east, \'irgo;

to the south-west, (leniini (high up), Procynn, and

Siriiis (setting).
West . Taurus, Pleiades, and Orion, all rather

low down.
East . Antiinis, Corona, and Hercules; to the

north-east, Vi-ga rising.
Minima of Algol may be observed on the 7th at
10.38 p.m., loth at 7.27 p.m., and 30th at y.io p.m.

Date

April 2

„ 4
,,28

,,29

Star's
Name.

49 Librae . .
B.A.C. 339«
m Virginis . .
B..\.C 4S2S

Magni-
tude.

5-6
5-9
53
6-0

iJisappcarance.

Mean Time.

II. 4 p.m.

925 pm-

10.6 p m.

9 40 p.m.

Angle from
N- point

94
118^

Reappearance.

103-
75'

Mean Time.

12.9 a.m.
10.33 p.m.
11.18 p.m.
10.37 p.m.

Angle from
N. point.

Moon's
Age.

297
284°

303"
327°

d. h.

17 17

9 o

13 o

14 o

The Planets. — Mercury should be looked for in the
N.W. shortly after Sunset from the 15th to the end of the
month. .Vbout this time the planet is in the most favour-
able position for observation for the present year, and sets
about two hours after the sun. On the 21st he arrives at
greatest easterly elongation of 20 1 1', and although this
is not so large as the autumnal elongation, the greater
inclination of the ecliptic to the horizon at this time puts
the planet into a much more favourable position tor
observation.

The diatneter of the disc is 8"-o.

\'enus cannot readily be observed, as she only rises
about half an hour in advance of the Sun, and is thus
lost in the bright dawn.

Mars is practically unobservable, as he sets before it
is really dark.

Jupiter was in conjunction with the Sun towards the
end of last month, and is therefore too close to the Sun
for observation.

Tei.i;sc()Mc Oi3Jec'is: —

Double Stars:—-, N'irginis, Xll.'' 37"% S. o'-' 54', mags.
3, 3 ; separation 5"'7. Hinary system ; both components
are yellow, though one is of a deeper hue than the other.

3-m.

An eyepiece of a power of 30 or 40 is reijuired
to effect separation.

rr Bootis, XIV.'' 36™, N. 16^ 53', mags. 4, 6; separa-
tion 6". K'equires a power of about 40.

I Boc/tis, XIW' 41"', N. 27° 30 , mags. 3, 6i; separa-
tion 2"-7. Very pretty double, with good colour contrast,
the brighter comiwjnent being yellow, the other blue green.

;. Bootis, XI\'.'' 47™, N. 19' 31 , mags. 5, 7; separa-
tion, 2"'4. Binary ; one component being orange, the
other purple.

Clusters :— M 3 {Canes Vauitici). XUl.'' 38"% N. 28 48'.
This object, though really a globular cluster of myriads
of small stars, appears more like a nebula in small tele-
scopes. It is situated between Cor Carnii and Anturus,
but rather nearer the latter.

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

ASTRONOMICAL.

M. Ja.nsserv's Photogra.pKic Atla^s of
the Sun.

Some twenty-eight years ag(i, M. Jansscn set on foot a
photographic study of the solar surface at the Meudon Obser-
vatory, of a somewhat special kind. His object was to obtain
the greatest possible sharpness of definition, and for this pur-
pose he had an objective constructed for him by I'razmowsUi
which brought the rays near the G line of the Fraunhofer
spectrum, and practically these alone, to a well-defined focus.
In conjunction with this instrument he used collodion plates,
sensitised by bromo-iodide, in which the iodide predominated,
with a small range of sensitiveness which corresponded to the
region of the spectrum for which the object glass had been
constructed. The photographs were therefore obtained
almost by monochromatic light, and were exceedingly' sharp.
The objective employed had an aperture of 0-135 metres and
focal length of 2 metres, a secondary magnifier enlarging the
image of the sun in the telescope some 15 diameters. Some
of the most characteristic and best defined from the store of
over 5ooo negatives which have now been accumulated at the
Meudon Observatory have been reproduced, enlarged four
times from the originals, in a superb atlas, recently published
by M. Janssen. These plates, 30 in number, and 21 inches by
i<S in size, are on a scale of about 4 feet to the solar diameter,
and show the intimate structure of the solar surface with a
minuteness and detail never seen in any previous publication;
the minute granulation of the surface and the dift'ercnt forms of
the reseau photospherique being most admiralily illustrated.

Some Peculiarities of Comets* Tails.

In an article in " Popular Astronomy," illustrated by a
number of beautiful photographs. Professor Barnard draws
attention to some peculiarities apparent in the photographs
of some recent comets which do not seem to be sufficiently ex-
plained by the well-known theory of Professor Bredikhine of
the repulsive action ex-ercised by the sun upon the cometary
nucleus. The comets specially remarked upon are those of
Swift, 1902 : Brooks, 1893 ; and liorrelly, 1903. The remark-
able way in Avhich the tail of Brooks' Comet was contorted and
broken on October 22, 1893, seems to clearly indicate that it
had encountered some resisting or disturbing medium. The
case of Borrclly's Comet was not less remarkable, but of a
diflerent kind. Here a tail, itself apparently uninjured, was
sec'U at a distance from the head. In this case there seems to
have been a slight but sudden change in the direction of the
emission of matter from the comet's head, thus cutting off the
supply from the first formed tail. The detached tail, however,
showed no clear evidence of acceleration in its motion, and
this would suggest that the sun had little to do with its flight
into space.

Radial Velocities of Twenty StaLrs of the
Orion Type.

Amongst the Decennial Publications of the University of
Chicago IS a Memoir by Messrs. Edwin B. P'rost and Walter
S. .-Vdams upon the motions in the line of sight of twenty stars
of the Orion type. The photograjihs of these spectra were
obtained with the Bruce spectrograph attached to the great
refractor of the Yerkes Observatory. I'he comparison spectrum
was always that of titanium, and sometimes, in addition, iron
or chromium, or else a helium tube wliich also gave the
hydrogen lines. The absolute velocities of the twenty stars
observed was evidently very small, and when corrected for the

solar motion gave 7 kiloiuitri-- a second as the mean of the
twenty radial velocities. The proper motions of these twenty
stars (not their i-lciI radial velocities, as Professor Frost's
memoir has been curiously niisreadi are exceedingly small ;
the mean for nineteen of them only being o"oi5 on a great
circle, which is much smaller than for solar stars of corre-
sponding brightness, and indicates that the Orion type stars
are, as a class, very remote. A classification of thirty-one
stars of the type is given at the end of the paper, according to
the character of the lines of helium, silicon, nitrogen, and
o.xygen in their spectra.

The Starrs of Secchi's Fourth Type.

Another of the Decennial Publications is a Memoir by Pro-
fessor Haleand Messrs. EUerman and Parkhurst onthe spectra
of stars of the type of 152 Schjellerup, the Fourth Type of
Secchi's classification. The spectra of eight stars were
examined, and some most important conclusions reached. A
great number of bright and dark lines were detected over and
above the violet flutings of cyanogen, and the flutings of the
Swan spectrum. Of the dark lines, a large number were
measured, showing the presence of carbon, hydrogen, mag-
nesium, sodium, iron, calcium, and other metals recognised m
the sun. The carbon and metallic vapours appear to be very
dense, and to lie immediately aliove the photosphere ; above
these dense vapours are others giving rise to the bright lines,
of which about 200 are present. None of these could be
identified with certainty, but a few may possibly correspond
to the bright lines of the W'olf-Rayet stars, which the Fourth
Type spectra resemble in some other characteristics. Many
lines widened in sunspots are represented by strong dark lines,
suggesting that these stars may be largely co\ered by spots
akin to those of our sun. Some twenty per cent, of the Type
appear to be variable, exceeding the proportion observed in
the case ofThird Type stars. Professor Hale suggests that the
Third and Fourth types should be classed together as pro-
bably having developed from stars like the sun through loss of
heat by radiation.

ZOOLOGICAL.

The Colours of Lobsters and Prawns.

ExPKKiMENTb uiidert.ikeii many years ago were belie\ ed to
demonstrate that the colouring of Crustacea was largely, if not
entirely, of a protective nature. F"or instance, when prawns
or young lobsters were placed, in broad daylight, on black
dishes, the pigment-bearmg bodies, or " chromatophores,"
in their integument were observed to expand, with ihe result
that a dark type of coloration in harmony with the tone of
the surroundings was produced. Conversely, when the
creatures were placed on a white dish, the pigment bodies
contracted, with the resulting production of a pale tone of
coloration, harmonising so tar as possible with the back-
ground. Moreover, if the crustaceans were deprived of sight,
no such adjustment of colouring occurred, although it took
place immediatelv that vision was restored.

From these and other experiments, it has become the cur-
rent opinion that the pigments of crustaceans are superficial
and sporadic in distribution, that they are confined to single
cells— chromatophores — of the epidermal or connective
tissues, and that they are either protective in function or form
a waste functionless product of development.

Recently, the subject has been taken up anew by Messrs.
Keeble and Gamble, the results of whose investigations
appear in the Philosophical Tnuisiutiuiis of the Royal Society.
While fully recognising the paramount influence of background
on the colours of crustaceans, the authors find themselves
compelled to adopt an attitude of reserve and indecision in
regard to most ol the foregoing points. They state, for in-
stance, that even the protective function of colour is not
definitely determined by experiment : while pigment in crus-
taceans may be deep-seated, and may also occur in complex
organs not 'functionally related to one another, l-'urther in-
vestigation is necessary before anything definite can be
predicated as to colour-function in these creatures.

April, 1904.]

KNOWLEDGE .^v SCIENTIFIC NEWS.

Arv English Spiral-Sawed Shark.

For many vears certain remarkable bodies, somewhat resem-
blins a large watch-sprinj; armed on the convex side with teeth,
have been known from the Carboniferous and Permian rocks ol
various countries ; the most nearly complete coming from
Russia. There has, however, been much uncertainty as to
their true nature. At first they were supposed to be the fin-
spines of fishes ; but the aforesaid Russian specimens clearly
showed that they belong to the front of the jaws of sharks, and
that they are true teeth, which are mounted upon their sup-
porting base in such a manner as to form a spiral. Hence the
name of spiral-sawed sharks for the group to wliich they per-
tained. Hitherto this group has been known only from North
America, .Australia, Japan, and Russia; the type genus being
Edesttis. Recently, however, Mr. E.T. Newton, in the Qiuirhi-ly
Journal of the Gcohi^ical Society, has described part of the
" saw " of one of these remarkable sharks from a marine band
in the Coal Measures of Nettlebank, North Staffordshire.
giving the name of Edcstus triscrraliis to the species it
represents.

The Medusa of Lake Tanganyika.

The discovery of the Freshwater Nfedusa, Limiioclida Tan-
giinyiku, in Lake Victoria, which was announced to the Zoo-
logical Society of London at their meeting in December last
by Professor Rav Lankester, is an event of some scientific
importance, as this remarkable form had been previously be-
lieved to be entirely restricted to Lake Tanganyika, and to be
one of the most significant pieces of evidence in favour of Mr.
Moore's theory of Lake Tanganyika having been formerly
connected with the ocean. When Professor Lankester
exhibited his specimens he was not quite certain that they
had been obtained in Lake Victoria, but we believe that
further information recently received leaves absolutely no
doubt on this point, the specimens having been tak(Mi in Kavi-
rondo Bay by Mr. Hoble\-. Moreover, confirmation on this
subject has been furnished by a French Naturalist, M. Ch.
Gravier who obtained nine examples of this Medusa in the
Bay" of Kavirondo on the i6th of September last year, as has
been announced by M. Perrier to the French Academy of
Sciences. ^L Perrier agrees with Professor Lankester in con-
sidering the Medusa from Lake Victoria to lie identical with
that of Lake Tanganyika, and of this we believe there is no
doubt.

Some people have thought that this remarkable discovery is
rather a serious blow to the theory of the " halolimnic" nature
of Lake Tanganyika, but Mr. Moore does not seem to be at all
disconcerted by it. In a letter to Nature (of February i8th) he
maintains that so far from this fresh piece of knowledge
"being in any way antagonistic to the view in question," the
existence of the Medusa in other Lakes is "exactly what one
would anticipate, supposing the halolimnic theory to be
correct." Mr. Moore thinks that it may be explained in
two ways. It is quite possible, he believes, that the Medusa
may be a recent importation into Lake Victoria from Lake
Tanganyika, caused by the opening of new trade-routes
between the Lakes, and the carriage of water in gourds and
other vessels from one lake to another. If this shall be found
not to have been the case, then future researches will probably
result in the discovery of the rest of the " halolinmic fauna,"
or part of it, in Lake Victoria. This, it is maintained by Mr.
Moore, would confirm the view that he has already put for-
ward, " that the ancient sea from which the halolinmic relics
sprang spread nmch further towards the east than was at first
supposed."

To settle this and many other interesting problems it is
certainly advisable that a much more accurate investigation of
the Fauna and Flora of Lake Victoria should be made than
has yet taken place. Lake Tanganyika seems to have more
attention paid to it as yet than Lake Victoria.

The Palolo Worm.

In a recent issue of our contemporary, the A meruan
Naturalist, Mr. W. McM. Woodworth gives an interesting
account of the palolo worm of Samoa and Fiji. For more
than half a century the appearance of swarms of these worms,
apparently always just before the full moon, in October and
November, has been familiar, and it has also been known that

the worms forming those swarms are always imperfect. It is
now ascertained tliat these palolo arc the slender posterior
generative portion of the annelid known as liiiiiiic viriilis,
which at the swarming season becomes detached and free-
swiunning. This portion is very much longer tlian the proper
body of the creature, which is, however, much stouter. The
complete worm dwells in coral-reefs, into which it burrows ;
and, curiously enough, its existence there was quite unknown
to the Samoans, to whom the demonstration of its presence by
Mr. Woodworth came as a revelation. The worm only attains
its full dimensions shortly before the swarmint^ season.

A Precious Product.

According to a writer in the February number of tlie
/Zoologist, a lump of ambergris, weighing about 4! lbs., w.is
taken from tlu' intestines of a male sperm-whale killed last
June between Iceland and Norway, in about tlie latitude of
Trondhjem ; a very unusual resort, by the way, for cetaceans
of this species. Ambergris, which is very largely used in pcr-
fumerv, is solelv a product ofthe sperm-whale, and appears to
be a kind of biliary calculus. It generally contains a number
of the hornv beaks of the cuttlefishes and squids, upon which
these whales chiefly feed. Its market price is subject to con-
siderable variation^ but from £3 to £4 per ounce is tlie usual
average for samples of good quality. Mr. T. Southwell, the
writer referred to, states, on the authority of a correspondent
in the sperm-oil trade, that in 1898 a merchant in Mincing
Lane was the fortunate owner of a lump of ambergris weighing
270 lbs., which was sold in Paris for about 85s. per ounce, or

£i^'i^''- ... ,, .

African Insects.

Descriptions and illustrations of the entomological f.iuna of
Tropical -Africa are in course of publication in the Annaks of
the Congo Museum, issued at Brussels. In one of the two
latest parts, Mr. K. Lameere describes the longicorn beetles of
the sub-family Prionina:, while in the other Mr. H. Schouteden
writes on certain groups of flower-bugs. Both meiiioirs are
illustrated by coloured plates remarkable for their beauty of
execution.

Papers Read.

At a recent meeting of the Royal Society a communication
was read on the pharmacology of Indian cobra-venom, based
on experiments made by Captain R. H. Elliot, of the Indian
Medical Service. On the 3rd of March, at the Linnean Society,
Dr. J. G. de Man described certain species of the crustacean
genus Piild:inoii from Tahiti, Shanghai, New Guinea, and West
.Africa. The papers read at the meeting of the Zoological
Society, held on March ist, included one by Mr. K. T. Leiper
on A vagina incola, a new genus and species of the Proporiiia-,
with a note on the classification of the group ; and a .second,
by Dr. Einar Lijunberg, of Stockholm, on two specimens of
hybrid grouse of which the exact parentage is known. The
papers read at the meeting of the same Society on March 15
comprised one by Mr. F. E. Beddard on the anatomy of li/ards,
one by Mr. Lydekker on certain points in connection with the
skull and colouring of the extinct quagga ; a second by the
same author on the distinctive features of the Asiatic wild asses,
respectively known as the Chigetai and the Kiang ; one by
Mr. R. J. Pocock on a new African monkey, and one by Mr.
P. J. Lathy on additions to the list of Dominican buttertlies
{Rh op aloe era).

Certain interesting specimens were exhibited at the Zoolo-
gical Society's meeting on March i. In the first place. Dr.
(ilinther directed attention to hybrids between Reeves's
pheasant and the silver pheasant. Next, Mr. Thomas exhi-
bited the skull of a large buffalo killed by Colonel Delnie-
Radcliffe in S.W. Uganda, which was believed to indicate a
distinct local race of Bos caffer. The same gentleman also
displayed a new species of fruit-bat from P'ernando Po,
remarkable for its small bodily size. Thirdly, Mr. J. G.
Millard exhibited a collection of skins in illustration of the
life-history of the grey seal, whose geographical distrilnition
was discussed. A few other minor exhibits were likewise
made.

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

Corrigenda.

Owiiif,' to an unfortunate oversight, the author of the article
on the Ancestry of the Camel and writer of Zoological Notes
in the March Number had no opportunity of revising the
proofs ; the followin.t; corrections are therefore necessary.
P. 25, ist Col., line 17 from bottom, for ga:elhi rtMil f;ii:c!le.

,t ,, 2iid ,, ,, 20 ,, top ,, are ,, is.

.. ^fi. .. .. .. 10 ,. ,, ,, Li)ita ,, Uinta.

27. 'St .

., 26

, ,,

., Procamelas

Prociiinelus.

4 .

. bottom

,, Pliancheniu

, Pliauchenia.

.. 2nd ,

., I'J

> >i

,, Camelas ,

, Cavielus.

28, I St .

,. 28 ,

top

,, Aliicamclas

, Alticavielus.

.. 25 .

1 ..

,, Procamelas

, Procamelus.

s ,

, bottom

,. Paracamelas

, Paracamchis.

4-', ..

.. 33 ,

, top

., La da

, La do.

.. 2nd ,

ist line

.. A'»/0

, Giilo

.. .,

line 35 .

bottom

, Maiayensis

, Malayenses.

.> ..

.. 24 ,

, Parachivomys ,

Metachiromys

,. ,.

12 ,

, Soemmeringi

SLcmnierringi.

BOTANICAL.

The rare occurrence ofstamens developing inside the ovary has
been recently met with in a Caryophyllaceousplant, Mclandi-yum
ruhnim, and is made the subject of a paper by Professor F.
Bucbenau in the Bericlitc lier DeutscJitu Butuiiisclieii Gesdhcluift.
XXI. The material was collected in the neighbourhood of
Marburg, Germany, having tirst attracted attention on account
of the absence of petals. A closer examination revealed great
irregularity in the structure of the ovary and in the number of
the stigmas, and on making a section of the former it was
found to contain six to nine, sometimes ten, well-developed
stamens arising from its base, the central placenta, with the
ovules, being altogether wanting. Dr. M. T. Masters, in his
V'fgvtiilih- Teraioloi^y, refers to a Myrtaceous plant, Dicckca
itiosmicfoliii. in which a similar abnormality was found. The
ovary contained no ovules, but numerous stamens, in various
stages of development, were attached to the inside walls. In
other respects the flower appeared to be quite normal.

The standard work on the flora of South Africa is, of course,
the Flora Ciipciisi.-i. which was begun bv Harvey and Sonder,
and is being continued under the editorship of Sir \V. T.
Thiselton-Dyer. This work, of which anew part hasjust been
issued, gives full descriptions, with synonomy and localities, of
all the known flowering plants of Africa south of the tropics,
and is necessarily bulky and expensive. Professor Henslow's
South Afruaii Fluu-crini; Plants, lately published by Longmans,
Green, and Co., will be welcomed by those who seek a handy
inexpensive work on the South African flora, but who do not
require the fulness of the Flora Capi-nsis.

The very imperfectly known flora of Siam is being investi-
gated by Mr. F. N. Williams, who has commenced an enumera-
tion of the plants of this country in the last number of the
Bulletin lie VHcrhkr Boissier. His work is based on the material
in the Kew Herbarium. Collectors have paid very scanty
attention to this flora, and several sets of plants, said to be
from Siam, are shown to be from localities outside its boun-
daries, and cannot, therefore, be included in his enumeration.
Some preliminary remarks on the flora were made by the
same author in the Journal of Botany of September, 1903,
where he mentiors the interesting fact that the well-known
commercial product, Siam benzoin, is obtained not from Siam
but from a locality in the Lao province of French Indo-China'

PHYSICAL.

Chlorophacne.

Chlorophane is the name given to those varieties of Fluorite
(Fluorspar Calcium Fluoride), which possess to a noticeable
extent the property of " thermo-luminositv," that is to say,
of spontaneously emitting light when heated. The tempera-
ture at which this phenomenon takes place is not the same in
all cases, but varies with different varieties of the mineral —
the heat required being generally between 300 and 400' C.
On first heating little or no light is emitted, until what mav be
called the " critical temperature " is reached, when the Chloro-
phane glows brightly and continues to glow for some hours

after cooling to ordinary temperature, but more feebly. The
colour of the light varies, blue and green predominating.
Hagenbach found that the spectrum of phosphorescent Fluorite
consisted of onl}^ nine bands, four blue, two green, two yellow,
and one orange. .As the relative intensity of these bands is
continually changing, it is easy to understand the different
colours pre,sented by different varieties of this mineral. The
pure white Fluorite does not possess the properties of Chloro-
phane, apparently the presence of some other salt or impurity
is necessary, as in the case of phosphorescent Calcium Sul-
phide.

* * *

ChlorophaLne a.rvd P.adium.

Madame Curie states [Chanual .V.ai, \'ol. L.X.X.WUL,
No. 2293, p. 223), that: "Fluorite when heated undergoes a
change, which is accompanied by the emission of light.
If the Fluorite is afterwards subjected to the action of
Kadium an inverse charjge occiu's. which is also accom-
panied by an emission of light." This being so, what
effect would be produced by first acting upon the Fluorite
with Kadium, and then applying heat ? The following
experiment was devised for the purpose of ascertaining
this. A small crystal of Chlorophane was exposed for six hours
at a distance of two millimetres from 10 milligrams of Kadium
Nitrate (Giesel's preparation) in such a manner that only the
(3 and 7 rays acted upon it. The initial fluorescence excited
under these conditions was fairly bright, and persisted after
removal but slightly diminished in intensity, and when kept
at uniform temperature fell to half value in two to three days,
dying down to negligible quantity in six to seven days. The
changes in thermoluminosity were very marked, a very slight
rise in temperature, such as that produced by placing the
crystal in the palm of the hand, sufficing to increase the
luminosity about 100 percent. This increase is at the expense
of the duration of retained fluorescence. The "Alpha" rays
of Kadium are without appreciable effect on Fluorite. Careful
observations made with a Bismuth plate covered with a
deposit of Markwald's Kadio-tellurium (Polonium ?) of sufficient
radio-activity to cause a piece of Willemite to glow brightly
when in close contact, gave only negative results. It would
be of great interest to know the exact nature of the change
occurring in the chlorophane, whether it is of a chemical or
physical kind. — Ernest L. Arnibrecht, M.P.S.

[N.B. — The writer also finds that the above properties are
not confined to Chlorophane, but are also shown by Kunzite,
with which very pretty experiments may be made on above
lines.]

Wireless Telegraphy Experiments between
Germany and S\veden.

The Berlin Gesellschaft fiir Drahtlose Telegraphic some
time ago installed two wireless telegraphy stations on the
Norwegian Loffoden Islands, the two points chosen being
50 km. distant and separated by high continuous rocky masses,
so as to oppose serious obstacles to the passage of the electric
wave. These stations were designed for dry cell operation, in
order to ascertain whether communication over distances as
high as 50 km. would be possible with such small amounts of
electric energy. This, however, was found not to be the case
as the primary energy of a limited number of dry cells proved
insufficient, a cpnsumption of about 200 watts being necessary
to overcome the obstacles on the passage of the electric waves.

The experiments between Germany and Sweden, as con-
templated for some time past, were begun on December i6th,
when wireless telegraphy communication was secured between
Oberschiinweide, near Berlin, and Karlskrona, a Swedish naval
station, over a distance as high as 450 km. The results so
far obtained are said to be quite satisfactory.

The " Telefunken " system used is a combination of the
Braim and Slaby-Arco schemes which, we learn, is being fre-
quently used with the Swedish Navy.

The Nationa.! Physical La.boratory.

One of the prominent even tsof the past month w.is the annual
visitation and inspection of the important standardizing and
testing laboratory at Bushey House, Teddington. Erstwhile
a Koj'al domicile, the mansion and adjacent buildings are now

April, 1904.]

KNOWLEDGE c^- SCIENTIFIC NEWS.

devoted to experimental work di'siL;iu ,, , note the joint
interests of the nation's manufacturing industries (in the con-
duct of which appUed knowledse is requisite) and theoretical
inquiry of a scientific character. Probably few of the .general
public who visit Bushey Park in such numbers are aware of
the proximity of the National Physical Laboratory, still less
of its. aims, .although it is a public institution maintained by means
of the taxpayers" money. Here, however, a great work is unob-
trusively going forward.whose benefits spread themselves far .and
wide. Many .and varied are the investigations pursued. In
electricity, for example, is one on the effect of temperature on
the insulating properties of materials used "in dynamos,
motors, and transformers; in thermometry a researcli on the
specific heat of iron at high temperatures ; in metrology, the
standardization of the steel yard and nickel metre; and in
metallurgy a series of tests on nickel steel. Then, in the de-
partment of engineering, experts say that the inquiries in
hand are eminently useful to a producing country such as
England is, and hopes to remain, despite her foreign competi-
tion. Comprised in electrotechnics are tests on electrical
instruments, ammeters, wattmeters, voltmeters, and other in-
dispensable adjuncts to the needs of industry, .\gain. in
chemistry, optics, and photometry, the record of investigation
bears the same tendency.

The laboratory is, of course, a young organisation as yet ;
but its operations are ramifying in all directions under the
able giuidance of Mr. K. T. Glazebrook. F.R.S. But, as Lord
Rayleigh, the Chairman of the General Board, pointed out the
other day, unless adequate funds are provided to meet the
national purposes of the foundation the institution must fail
in accomplishment, and a starved laboratory would jirobably
prove a worse evil than none at all. Besides, it should be
borne in mind that Paris and Washington have recently fol-
lowed the example of London in initiating standardising
establishments intended to help national industries each, too,
is subsidised in a far more liberal way than in our own case.
The necessity for making better provision for the needs of the
laboratory has lately engaged the earnest attention of the
Executive Committee, and representations have been made
to His Majesty's Treasury- on the subject. A detailed scheme
for the future organization and development of the institution
has been drawn up and submitted. This, if approved, will
entail a revision of the existing Parliamentary grant-in-aid.
but in view of the special functions of the laboratorv, and the
sphere of usefulness that lies before it, strong hopes are enter-
tained of a favourable issue to the appeal.

COR.R.ESPONDENCE.

A Novel Electric Traction System.

To THE Editors ov •' Knowledge."
Sirs, — The scheme described under the above heading in
your March issue, taken from the Ekctrotechiiisclwr Aii^.cii^cr,
presents such curious features that one is inclined to doubt
whether it has been put forward seriously. To use electricill v-
heated steam-engines in preference to electric motors would
appear, at any rate at first sight, as an absurdity, as the
following considerations will show.

It may be safely assumed that the internal thermal efficiencv
of a steam locomotive does not exceed 10 per cent., I'.t'., only
10 per cent, of the thermal energy carried by the steam froin
the boilers into the cylinders is converted into work on the
piston. So that, accepting 90 per cent, as the efficiency of the
electric heaters, and assuming the mechanical efficiency of the
engines to be as high as go per cent., it follows that of the elec-
trical energy supplied to the V)oiler all that is available for
propulsive power is go per cent, of 10 per cent, of 90 per cent.,
i.e., about S per cent. Against this the ordinary electric loco-
motive would have, as stated in the article, an over-all
efficiency of 60 to 70 per cetit., or even more.

Now although the actual energy for a water-power installa-
tion in a sense costs nothing, the plant to develop it is very
costly ; and it may be safely predicted that it would not pay
to use a generating plant and transmission system eight or
nine times too large to save scrapping the steam locomotives.

This very large ratio .against the electro-thermal system
would, it is true, be reduced by the fact that every locomotive
would to some extent act as an eiiualiscr of the demand on the
power-houses, reducing the excess plant that would ha\e to be
installed ; but the larger system worked from one powerhouse,
the less this advant.agc would becoTuc ; .ind in ;iny c.isc the
excess of power retjuired by the electro-thermal system would
be enormous.

Even if under any conceivable conditions such a system
might prove advantageous, it is certain that the figures put
forward to justify the proposal are mitirely erroneous; and
this confirms one's doubts as to the scheme having emanated
from any authoritative ([uarter.

The first point to be noted is that it is proposed to raise
the temperature of the water from 10" to up C. recpiiring
iHo calories per kg.; but lyo" C. is said to correspond to a
steam pressure of 50 kg. per sq. cm. As a matter of f.ict,
iqo° C. (= 374" F.) corresponds to satur.ited steam at about
170 lbs. per square inch (above atmosphere), whilst 50 kg. per
sq. cm. is equivalent to 710 lbs. per square inch. However, as
pressure is not referred to further by the writer this discre-
pancy does not matter much.

But next it is said that to raise 4000 litres of water through
180" C. will take 4000 X 180 = 720,000 calories; this is true
if it remained water, but this amount of heat is by no means
enough to convert the water into steam, i.e., to provide the
so-called latent heat of evaporation. So that, whilst it might
be correct to say that a consumption of 1000 kg. of hot water
per hour at lyo" C. would take zz^ kilow.itts, it is very far
from the truth to say the same of 1000 kg. of steam.

To convert 1000 kg. of water at 10- C. into steam ;it i()o' C.
will take, not 180, but about 635 calories per kg.; in other
words. 635,000 calories per hour must be provided ; and if
I calorie in the boiler requires i'275 watt-hours, the electrical
energy will have to be supplied at the rate of 810 kilowatts, or
more than three-and-a-h.alf times the figure given.

.\n electric locomotive taking 810 kilowatts might be relied
upon to give 700 to qoo effective horse-power; the electric
steam locomotive taking the same electrical power, and evapo-
rating steam at the rate of 1000 kg, per hour, would not give
more than 100 to 125 effective horse-power, if so much.
Your obedient servant,

.A K SOLD G, Hansard.

53. Victoria Sti'eet. Westminster, S.W'.,
March cj, 1904.

Snake Stones.

To THE Editors or " Knowledge."

Sirs. — Some time ago I was much interested in a series of
articles in the scientific column of a weekly paper on the
subject of " Snake Stones." Nothing was said at the time in
connection with Brazil, and as I lived in th.it country for
several years it may be interesting to some of your readers to
have a word on the subject. " Snake stones " are not stones
at all. at any rate not in Brazil, and I should think they would
be much the same all over the world. • In the articles above
referred to there appeared to be gr*-at doubt as to what they
are. The only ones used in the part of Brazil where I was
were made from the horns of young deer, burnt or carbonised
in a peculiar manner, which leaves it very suctorial, and which
is kept as a close .secret by a very few men who make them
for sale or barter, and try to make out that they have alu)ost
supernatural power to heal snake bites. They are usually
sold in pairs, and are not by any means common. In form
they are about one inch in length, four-sidcKi, and slightly
tapering to one end. When anyone is l>itten by a snake, one
of these " stones " is placed on the spot and held close, while
a band of some sort is tied tightly round the limb a little way
back towards the trunk. The " stone " is allowed Jo remain .
on the wound until its own weight makes it f.dl ofl, when it is'
presumed all the poison has been extracted. It is then
dropped into milk and allowed to soak. It is said th.it if
the person is to get healed theiailk will turn to ,i dark bniwn.
colour, the fact being, I suppyse.'fMat the blood held by tge .
stone has that effect. As usual 'with these things, there are
many superstitious beliefs in connection with these "stones,"

■^.%

KNOWLEDGE & SCIENTIFIC NEWS.

[April, 1904.

and the cure is supposed to be miraculous; whereas I suppose
that it is really due to the great capillary attractive force they
possess, which extracts a certain amount of blood, and with it
the poison. After being thoroughly washed out and dried
they are ready for another occasion. Yours truly,

James Searle.
[Some experiments recently made in the Government Bac-
teriological Laboratory of Natal ha\e shown that the
mysterious curative properties ascribed to snake stones
are quite illusory. — Editor.]

The Ancestry of the Elephants.

Sir, — In the very interesting article on the above subject
by Dr. Smith Woodward in the February number, I notice
that he calls the fig. No. 6 on p. 13— (Head of Tetrabelodon
angustidcus restored) — a fanciful sketch. As a matter of fact,
there has been introduced into it a series of circular wrinkles
evidently copied from those on the proboscis of the African
elephant figured just above it. But it is clear that, as this
proboscis was not pendent, no such wrinkles would appear.
Moreover, it would seem more probable that its form would
not be circular, but rather shaped to fit the elongated chin.

In that case the mouth would act as a long pair of leathery
tweezers, very suitable (with the help of the incurved tusks)
for gathering in large mouthfuls of long, quick-growing marsh
vegetation. The sharp incisors would enable this to be
quickly cut off, and the ponderous animal could without delay
move his weight on to firmer ground to masticate the food at
leisure.

As the species moved further north to harder ground and
tougher vegetation, a more prehensile grip would be useful
rather than a speedy way of gathering food together, whereas
the incurved tusk and elongated mandible would not only be
useless but highly inconvenient. Thus as the proboscis
became longer and rounder, the lengthened chin disappeared
entirely ; and the mammoth with its highly developed molars
was able to subsist even on the hard and tough vegetation
within the Arctic Circle.

Herbert Drake.

Verwood, Dorset, February 26, 19(^4.

REVIEW OF BOOKS.

Animal Studies, by David Starr Jordan, Vernon Lyman
Kellog, and Harold Heath. (New York and London :
Appleton and Co., 1903.) This admirable little treatise is one
of the " Twentieth Century Text Books," and bears a very
close resemblance to the volume on " Animal Life " — also of
this series by the same authors — reviewed in the columns of
"Knowledge" in igoi. It differs indeed, mainly, in the
addition of several chapters on Classification ; and on the
economic value and past history of animals. As an elemen-
tary text book of Zoology it must take high rank among works
of its kind, and will doubtless find a ready sale in this
country. Here and there, however, great opportunities have
been missed, and more or less serious mistakes are made.
Thus, in the chapter on the Classification of Birds, the auks
and pufiins are placed with the grebes and divers, the authors
having been apparently led astray, like the older systematists, by
the curious structural resemblance which these birds present
in common. As a matter of fact, however, the resemblance
to the grebes and divers which the auks, puffins, and guille-
mots present are entirely adaptive. Their nearest relatives
are, without question, the plovers and gulls. So, too, with
the gulls and terns, these have nothing whatever to do with the
petrels and albatrosses with which they are associated in this
book. The resemblances which they severally present are
again adaptive. It is equally misleading to place the owls
with the accipiters. Turning to the mammals, we may remark
that, as with the birds, the classification adopted is antiquated.
Nevertheless, in spite of the defects to which we have drawn
attention, the work is one which we can heartily commend.

Pictures of Bird Life, by R. B. Lodge (Bousfield;, illustrated j

27s. 6d. net. — Mr. R. B. Lodge has produced a most delightful
book. The illustrations, which are very numerous, are all re-
produced from his own photographs of birds and their nests
taken from life. We see many such photographs nowadays,
but none better than those reproduced in this book. There
are eight full-paged plates reproduced by the three-colour
process from photographs coloured by hand. We must con-
fess that we would sooner have had these photographs with-
out the colouring, which, in most cases, is not altogether true
to Nature. The letterpress is interesting, and often very in-
forming. Mr. Lodge has made the most of his opportunities,
and tells us how and where he obtained his photographs. He
has photographed birds in the Dutch marshes, Spanish inaris-
mas, and Danish marshes and forests, and in many places in
England besides. He gives many valuable hints to those who
would take up bird-photography, and describes several in-
genious devices and tricks which he has himself used with
success. The most notable of these is his automatic electric
photo-trap, whereby he traps the bird's portrait by hiding the
camera and inducing the bird by bait or otherwise to touch a
piece of silk, and thus set an electric battery at work to release
the shutter of the camera. Many of Mr. Lodge's observations
on the habits of the birds which he has watched so long and
so closely while trying to secure their portraits are most valu-
able. He may not have discovered much that was unknown,
but his remarks are the result of direct and careful observa-
tion, and this can never be without great value. There are
several repetitions in the book which might have been avoided
by more careful editing. The sentence, " The Hooded Crow
I do not remember seeing so far south" (Enfield) (p. 124),
might be put in a less ambiguous form. The bird is, of course,
to be seen commonly further south than London. Mr. Lodge
will find that the vibratory noise made by woodpeckers is
heard not only in the spring (p. 138). But these are only
small points, and are only mentioned in view of a possible
second edition of this excellent book.

BOOK NOTICES.

The Grant and Validity of British Patents for Inventions, by

James Roberts. .M..-\., LL.H. (John Murray, one vol. ; price
25s.). This work has been written for and from the point of
view of the inventor. It is intended to enable him to confine his
claims to what can be supported and to avoid errors in his
specification. The first part consists of the principles and
rules affecting the grant and validity of British patents, and
the practice respecting the atnendaient of specifications both
before the Comptroller-General and the Law Officers of the
Crown; the second part of abstracts of cases, illustrating
the application of these priuciples; and the third part, the
statutes and rules. The scope and tenour of the book are such
as to make it useful to practising lawyers as well as to inventors.

Mathematical Crystallography, by Harold Hilton, M.A.
(Oxford : The Clarendon Press). Mr. Hilton's expressed
purpose is to collect in this volume those results of the
mathematical theory of crystallography which arc not provided
in the modern text books on that subject in the English
language. He includes a valuable summary of the geometrical
theory of crystal structure which the labour of Bravais Jordan.
Schneke, Fedorow. Schoenflics. and Barlow have now com-
pleted. It is a student's book ; an advanced, but an extremely
valuable one.

Zoology, Descriptive and Practical. (Two Vols. D. C.
Heath; price 4s. 6d. and 2S.) — The general plan of the
volumes is to introduce each of the larger groups of animals
by a careful study of a typical representative.

BOOKS RECEIVED.

The Naturalist's Directory (L. Upcott Gill) :— Introduction to
the Study of I'hvsical Chemistry, by Sir William Ramsay— a
wholly admirable allocution to stude'nts. (Longmans, Green.)

Martins Up-to-DateTables of Weights and Measures. (T.Fisher
Unwin.)

April, 1904]

KXOWLl'DGl-: lS: SClENTll'lC Xl-WS.

Modern Navigation, by W. H:ill. K.N. (Organised Scionce
Sories.i L'niversitv Tutorial I'ross. _

SeconJ Stage Botany, by J. M. Lowson. (Organiseci Science
Series. I Iniver^itv Tutorial Press.

Entropv.bv lames Svvinbunu-. iConstable.l

The .Modei Engineer Series.— X-rays, Simple Experiments n
Electricity, The Locomotive, Acetylene Oas. ( IVrcn al Marshall.)

A School Geometry. Tarts 1. IV.. by H. S. Hall: IV. and
v.. F. H. Stevens. (Macmillan.)

We have received from Messrs. Nalder Bros., ot \\ est-
minster, their catalogue of Electrical Testing and Scientific
Instrument!!. The catalogue is, in itself, an e.\trenuly in-
teresting summary of the investigations now binng carried on
in various departments of research, and special attention may
be directed to the photometric apparatus.

Tin following hocks an- in pnpurtttUm at the Claraulon Press i -
Suess' •' Das Antlitz der Erde." authorised English transla-
tion, by Dr. Hertha Sollas. edited by Professor W. J. Sollas,
with preface by Professor Suess for the English translation.
Koval i-vo. ,, ,

"Index Kewensis Plantarum Ph,anerogamarum. Supple-

mentum secundum. 4to.

Goebels -'Organography of Plants," authorised English
translation, by I. Bayley Balfour, M..\., F.K.S. Vol. II.
Roval Svo.

Mr. Henrv Frou.dc u-ill also publish shortly :—

•• \ History of the Daubenv Laboratory," bylK. T. Gunther.

Conducted by F. Shillington Scales, f.r.m.s.

Royal Microscopical Society.

February 17, Dr. Henry Woodward, Vice-President, in the
chair. An old microscope by Bate was exhibited, probably
made early in the last century. Mr. Stringer contributed a
paper on an attachment for reading the lines in a direct-vision
spectroscope, and Mr. E. M. Nelson a paper on the vertical
illuminator. The author said that, after lying in abeyance for
25 years, the vertical illuminator had lately come into notice
for the examination of opaque objects, and especially for the
microscopical examination of metals. He criticised the four
forms of this apparatus at present sold, namely, those known
as the ToUes, Beck, Powell, and Reichert forms, and said
that a vertical illuminator must not be an oblique illumina-
tor, but must be capable of illuminating the full aperture of
the objective with a parallel beam of light. It must not impair
the use of the objective for ordinary work, and must, there-
fore, not be a permanent attachment. The reflector must be
placed near the back lens, and there must be some method
for regulating the illumination. Mr. Nelson found that the
Powell form, which, like Beck's, consists of a nosepiece con-
taining a reflector, more nearly conformed to these conditions,
but the reflector should be made much larger and the hole in
the side of the nosepiece should be as large as the Society's
gauge. To obtain the best advantage with vertical illumination
oil-immersion ol>jectives should be used. The distance from
the source of light to the mirror and thence to the objective
should be equal to the distance from the eyepiece to the
objective. At the hole at the .side of the nosepiece there should
be a carrier for diaphragms of various sizes in preference to a
wheel of diaphragms or an iris. There should also be a strip
of metal with a slit in it which could be drawn across the hole
in the nosepiece, and the direction of the slit should be in a
line with the edge of the flame of the microscope l.uiip.
Another paper l)y Mr. Nelson, "On the Influence of the Anti-
point on the Microscopic Image Shown Graphically" was also
read. The author referred to a papt^r in tlic Journal for 1903
on "A Micrometric Correction for Minute Objects." wherein he
stated by way of illustration that, if one of the minute spinous

hairs on a blowfly's tongue was exaiuiiied on a bright ground
and on a dark ground, a considerable difference in the sizes of
the two images was diseeniilile, aiul that the diflerence was
caused by anti-points. .\ talile was also given showing the
amount to be ailded to the niicronietric ineasureinent of the
image seen on the bright ground to bring it up to its true \ alue.
Mr. Gordon, who had originated the theory of the anti-point,
had made accurate drawings of the two images of the hair,
and the ratio of the breadths of the hair in the drawings was
as 45 to 05. Applying the corrections given in the table to
the measurement of the apparent size of the hair on a bright
ground, the actu.il size works out to 12 per cent. more. A
ditference in the apparent size of objects when viewed on a
bright or dark ground was recognised many years ago, but
never explained, but M r. Gordon's admirable anli- point theorem
has unlocked the riddle. Mr. Keith Lucas followed with a
paper "On a Microscope with (Geometric Slides," the principle
enunciated being .applied by the author of the paper to the
fine and coarse adjustments' and to the sub-stage of a micro-
scope, which was illustrated by lantern slides.

The Qviekett Microscopical Club.

The aniiu.il gem ral meeting was held on 1 i bruary 19 at
20. Hanover Sipiar.-, the President, George Massee, ICsq.,
F.G.S., in the chair. .Xfter the usual business had been trans-
acted, a ballot was taken resulting in the election of Dr.
Edmund J. Spitta, L'.K.A.S., as President for the ensuing year.
Mr. Frank P. Smith was elected Editor in succession to Mr.
D. J. Scourfield, and Mr. Arthur Earland, Secretary. Dr. G. C.
Karop, who has held the secretaryship for over twenty years,
goes into well-earned retirement, carrying with him the grati-
tude and esteem of all the ineml)ers. The other ofticers werc^
re-clectcd.

The President delivered his annual address, dealing with
the commoner fungoid diseases of garden trees and plants.
These may be divided into two groups, according to whether
the mycelium of the fungus is situated in the woody tissues of
the plant ("perennial mycelium "), or whether only the season's
growth, the leaves and fruit .are affected. The first division,
of which the well-known " peach-curl " is an instance, is by
far the more serious of the two, it being practically impossible
to cure a plant which has become badly infected. In the
second division, the plant becomes automatically purified, for
a time, on the removal of the infected leaves, &c., either artifi-
cially or in the course of nature, and if suitable measures are
taken to prevent the germination of the spores in the following
season, the plant may be wholly cured. Fire is the best
destructive agent; the infected leaves should be burned.
Spraying is ineffectual, for the mischief is under the surface,
and spraying tends to spread the disease to fresh hosts by
washing the spores off the infected plants.

The chief causes of fungoid disease in cultivated plants are
overcrowding and the use of chemical manures, which kill the
nitrifying bacteria of the soil and stimulate the plant to an
excessive and weakly growth.

After the usual votes of thanks. Dr. Spitta was installed in
the Presidential Chair, and in returning thanks for his elec-
tion, referred t<i the analogy between the fungoid diseases of
plants and the zymotic diseases affecting man, especially
typhoid and diphtheria.

It is an open secret among microscopists that the (.Hiekett
Club's position at 20, Hanover Square has lately been some-
what precarious, owing to the general rise in rents and the
keen demand for accommodation in the building of the Royal
Medical and Chirurgical Society. I am therefore glad to be
able to say definitely that the Committee has succeeded in
obtaining an extension of their tenancy in their old quarters,
with retention of all their present accommodation, though at .1
considerable increase of rent, which will, I trust, be justified
by a corresponding increase of membership. To the amateur
microscopist, especially the Londoner, the (Juekett Club, with
its very low subscription of los. per annum, without entrance
fee, offers many advantages. The announcement was made at
the annual meeting that a new catalogue of the Club's fine
library of about ijoo volumes was in course of publication,
and this should still further increase the popularity of the
Club. Applications for membership and inquiries relating to
the Club should be addressed to the Hon. Secretary, Mr. A.
Earland, 31, Denmark Street, Watford, Herts.

KNOWLEDGE & SCIENTIFIC NEWS.

L, 1904.

The Journal of Applied Microscopy.

I am informed by Messrs. .\. E. Staler and Co. that the
-American Journal of Applied Microscopy will be discontinued
after the appearance of the November and December numbers
of last year. This is a matter for sincere regret, as the journal,
though distinctly technical, was a really valuable one. and it is
unfortunate that it should not have met with sufficient support
to justify its continuation. We are none too well supplied
with microscopical literature, and it is strange that endeavours
to provide for our deficiencies in this respect do not meet with
more support. I fear that in the case of the journal referred
to. the unfortunate and recurring arrears of publication, due. I
believe, to the regrettable illness of the Editor, was respon-
sible for the loss of no little support. Those of our readers
who may wish to complete their sets may be glad to know
that Messrs. Staley have a large number of back numbers in
stock, and will be pleased to send them-to any subscribers for
the sum of 2d. each.

New Pond Life Tanks.

Messrs. Flatters and Gamett. of Deansgate, Manchester,
have sent me for inspection a new tank for the study of pond
hfe. It is made of one solid piece of glass, and is not unlike an
ordinan,- large goblet with flattened sides and square corners,
standing on the usual round stem and foot. The sides are
polished on the outside to prevent the usual distortion due to
the une\ enness of glass, and the depth from front to back is
such that an ordinary pocket lens can be conveniently used. '
The size of the tank sent to me was 4J inches high, 4 inches
wide, and i, inch deep, and it was very steady. Leakage was

of course impossible, the tank was easy to clean, and the price
very moderate — namely. 3s. gd. I understand these tanks are
made f inch high. liinch wide, and f inch deep at about half
the price of the stand mentioned above, and also in a larger
and more elaborate form, lined with opal glass and mahogany
frame at the ends and bottom.

Preserving Orthoptera.

Mr. J. \V. Williams, M.R.C.S., F.L.S., writes to me. in con-
nection with the note last month on preserving orthoptera,
that he has found dipping the specimens into a weak solution
of albO'Carbon in benzole is a better preservative against
inould than the carbolic acid plan therein suggested, and a
better curative also for mouldy specimens. Mr. Williams
says he has tried this plan consistently with satisfactory
results.

"^i ><^ >^> >^> -^^

Chess Colviran.

With reference to our note last month requesting
opinions on this subject, we have to state that, having
only received nine replies, of which seven were in favour
of the retention of the Chess Column, we feel that the
subject is not one of sufficiently widespread interest to
warrant our devoting the space to it, and, therefore, we
must, for the present at all events, discontinue the
Notes and Problems.

LAST YEAR'S WEATHER— APRIL, 1903.

DISTRIBUTION OF MEAN TE.MPERATURE.

RAINFALL.

3 0?

^ p^ — -^
' 57 . y

■JOk' 2 2S '2 °'

^4^

The greneral distribution over Scotland differed from the
normal, the isotherms ha\ing a north and south direction
instead of west and eaj»t. Elsewhere the differences were less
marked. T he actual \alues were, witliout exception, below
the average the deficienc> as a rule being from 2- to 3;^=.

Rainfall was ver>' irregular both as regards the quantit>'
and the frequency, there being localities of excess and of
defect in each district, iome stations having twice as many
days with rain as others in the same neighbourhood.

KDomledge & SeleDtifie Hems

A MOXTIILV JOURNAL OF SCIENCE.

Vol. I. No. 4.

[new series.]

MA\', 1904.

r Entered at "1
LStationers' Hall J

SIXl'ENCH

Contents and I\'otices. — See Page VII.

Racdio-Activity OLnd
R^QLdium.

By W. A. Shenstone, F.R.S.

1.
\\ E owe the discovery of radioactivity, and therefore
that of radium, to an accident, though the phenomenon
itself might almost be said to be a common one. Radio-
activity was first noticed by M. H. Becquerel, who, stimu-
lated, perhaps, by Rontgen's brilliant discovery of tie
X rays, was looking, in 1S96, for yet other new radiations.

The accident was as follows : There is a salt known as
potassium and uranium sulphate which, when it is exposed
to sunlight, becomes for a moment self-luminous, and
Becquerel was studying this phenomenon photographic-
ally.

His experiment consisted in placing crystals of the
salt above photographic plates well protected from light
by means of black paper, and then exposing the salt,
which was outside the black paper, to the direct light of
the sun. When he did this it became evident that some
radiation or some emanation was produced which could
penetrate the paper, for the photographic film immediately
below the salt was so acted upon that when the plate
was developed he obtained a silhouette of the crystals
more or less like that shown in fig. i, though this par-
ticular silhouette was given by a little radium bromide,
and not by the uranium salt studied by Becquerel.

Fig I. — Silliouetti given iv Radium,

One day, just as everything was ready for an experi-
ment, clouds covered the sun, and Becquerel put away

his plates with the crystals upon them, thinking them
spoilt. Several days afterwards liedevcloped the plates and
found to his surprise that thesiliioucttes were particularly
strong ones. lie found, in short, that the sun was not needed
to stimulate the salt; that this latter, without any such
stimulant, radiated or emitted something which was able
to penetrate black paper and act likr light on a sensitive
photographic plate. Me found as the result of further
experiments that this was no temporary quality of the
salt. It persisted for days and months, and, as he dis-
co\-cred subsequently, even for years. I'"urther, the same
power was possessed by other uranium salts and by the
metal uranium. Anyone who can take photographs can
verify all this for himself quite easily.

The radiations thus discovered by Becquerel are called
■'Becquerel Rays." They resemble the Riintgen rays in
many respects, and at one time were regarded as due to
Rimtgen rays. Thus, they cause damp dust free air to
deposit fog, make air conduct electricity, will pass througii
such substances as paper, glass, paraffin, quartz, sulphur,
Iceland spar, and thin layers of metal e\en more freely
than Rontgen rays, and they cannot be reflected, re-
fracted, nor polarized like the waves of which ordinary
light is composed. It was found, further, that they are
not homogeneous, but consist of several different
radiations which can be filtered off from each other as it
were, and can then be distinguished by their separate
characteristics.

Bodies which emit these remarkable radiations are
said to be " radio-active." As we shall see presently,
other metals besides uranium are radio-active, and also
the waters of some springs, as, for example, the waters
at Bath, and even solid earth.

Becquerel's great disco\-ery soon proved prolific. It
suggested to Madame Sklodowska-Curie the idea that
the great radio-activity of specimens of pitchblende,
which exceeded that of the uranium present in them, nuist
be due to special constituents, and so in her hands and
those of others led to the discovery of polonium, radium,
and actinium. And the remarkable properties of these
new substances in their turn have started new ideas or
revived old ones in several departments of science.

Madame and Monsieur Curie and their colleague, M.
Bemont, discovered polonium and radium, and INI . Debierne
was the discoverer of a third substance of the same class,
actinium. The method of working was to separate the
components of the pitchblende, which is a very complex
mineral, and to study the radio-active power of each con-
stituent. The results obtained with the bismuth and
barium from this mineral arrested attention, and presently
it was found that the former was associated with the sub-

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

stance now called polonium, and the latter with the radium
which plays such an important part in modern science.
Neither polonium nor actinium have as yet been isolated
in the form of a salt. The former in many ways resembles
bismuth, and its nature still remains doubtful. Radium,
on the other hand, yields salts — e.g., a bromide, a chloride,
and a nitrate. Its combining weight has been fixed by
Madame Curie at 112-5, and 225 is suggested for its
atomic weight. Itexhibitsadefinite flame spectrum, which
has been recorded by Messrs. Runge and Precht, and
which is given in fig. 2, whilst its spectrum in the ultra
violet has been studied by Sir William Crookes and
others, and affords a means 'of idcntilying it.

Fig. 2, — The Flame Spectrum of Radium.
The line <i has the wave length 4S26, b 6329, c 6349, d 6653. There
are bands about b c and <i as shown above.

Radium is generally regarded as an element, but as the
total quantity of the pure radium salts yet made would be
insufficient to fill a small egg cup, this statement must
still be taken with some reserve. The so-called pure
salts of radium possibly may be mixtures, but, for the
present, in the absence of any evidence to the contrary,
we may assume them to be salts of a new and peculiar
elementary substance radium.

Radium the element has not been isolated. Its salts
are so valuable, and the process of separating it probably
would be so wasteful, that it seems unlikely anyone will
attempt to prepare elementary radium at present.

The process of purifying a radium saU has not been
very frequently described, but it is simple enough in
principle. The raw material is the residue left after the
uranium has been extracted from pitchblende. A ton of
this material suitably treated may yield 10 or more kilo-
grams of a mixture consisting chiefly of the sulphates of
barium, lead, iron, and calcium, with a trace of radium.
This is converted into carbonates by heating it with a
solution of carbonate of soda, and the carbonates are
dissolved in hydrochloric acid, which converts them into
chlorides. The lead and iron in the mixture of chlorides
thus produced are got rid of by means of sulphuretted
hydrogen and ammonium sulphide, and the remaining
barium, calcium, and radium are reprecipitated as car-

•

Fi<;. 3. — Kailiographs of radium salt and uranium taken
siniultaneouslv.

bonates, again converted into chlorides, and then washed
with strong hydrochloric acid to remove the calcium
chloride. The residue consists of barium chloride con-
taining a trace of radium chloride. This is dissolved in
hot water and allowed to crystallize partially. The
crystals, which contain most radium, are separated
from the liquid portion, and the latter is then
evaporated to recover the remaining salt, and each of the
two portions thus produced is similarly fractionated. By
systematic work of this kind products were obtained first
nine hundred times as radio-active as uranium, then five
thousand times as active, then fifty thousand times, and
at last, it is said, a million times as active as the stan-
dard substance, the removal of the barium salt at the
later stages being facilitated by using solutions of hydro-
chloric acid in place of water for dissolving the mixture
of barium and radium chloride.

Some idea of the difference between the activity of
uranium salts and of radium may be got from fig. 3.
On the reader's right is the silhouette a, given by
one-sixth of a grain of radium in fifteen minutes. The
area about the faint dark mark above b a little to
the left of this shows the effect of a much larger quantity
of a uranium salt, the two being exposed side by side
over the same plate. The uranium salt, as will be seen,
gave no sensible result at all. The small dark mark
above b was added to indicate the centre of the area
exposed to the uranium.

The salts of radium, in their ordinary reactions,
resemble those of barium rather closely, but in other
respects they are remarkably different. Thus, they are
visible in the dark, and continuously evolve heat ; so
that a heap of a radium salt is always hotter than the
air around it. So great is the amount of heat evolved
that a gram-atom of radium gives out in a year as much
heat as a gram-atom of hydrogen when it is burnt in the
oxyhydrogen flame, and, moreover, as far as we know,
the radium would go on giving out heat at this rate for
many centuries. Its powers are destroyed to a great
extent if it is strongly heated (see emanation), but are
recovered spontaneously after a few weeks on cooling.

Radium, or rather its radiations, are very destructive.
A piece of cambric placed above a box containing a
little radium salt was found by Lord BIythswood to be
pierced with holes after two or three days. A photo-
graphic film exposed to one-sixth of a grain of radium
bromide in the author's laboratory for four hours by Mr.
W. D. Rogers (who has kindly prepared many of the
figures given in this article) yielded no silhouette because
the film was completely disintegrated and its remains
washed away during the developing process ; and the
caustic powers of radium salts, as is well known, are
thought likely to prove useful in surgery, and have some-
times produced very unpleasant effects when specimens
of the salts have been kept too long near the human body.
Its power of making air conduct electricity is shown by
the way in which a tassel of silk electrified by rubbing
with india-rubber collapses when radium is brought near
it, and by the rapid collapse of the lea\-es of a charged
gold leaf electroscope under similar circumstances. But
the prettiest way of observing this property of radium
is as follows ; —

Connect a spark gap at b, fig. 4, with an induction
coil and with a vacuum tube a — a large vacuum
tube gives the best result — as in the following figure.
Arrange matters so that the coil gives a very steady
discharge at the spark gap, and then draw back the
point and plate till the discharge just passes through the
vacuum tube, only an occasional spark crossing at b.
Then bring the radium close to the spark gap. When

\Y. I904..J

KNOWLEDGK & SCIENTIFIC NEWS.

you do this the vacuum tube will go out and the discharge
will not be re-established at the spark gap till you remove
the radium salt.

V\g. 4-

The coil must not give too strong a discharge, and the
discharge must be very steady. If this is secured, the
experiment can be brought off with great certainty every
time.

{To be coniinufd.)

Modern Views of
CKemistry.

By H. J. H. Fenton F.R.S.

A FEW further illustrations may be given of the simple
explanations which the ionic-dissociation hypothesis
affords of the properties and reactions of salts in solution.
Smce salts are highly ionised when dissolved in even a
moderate quantity of water, the properties of the solution
represent the joint or added properties of the ions into
which the salt has split up. The colour of the solution,
for example, is that of its ions ; solutions of most common
cupric salts are blue and nickel salts green. This is
because the acid-radicles (sulphate, nitrate, &c.) happen
to give colourless ions and the colours observed are
therefore due to the metallic ions. Most permanganates
are pink and manganates green in solution, because the
metallic ions (potassium, sodium, &c.) happen to be
colourless and the colours here are due to the acidic ions.
It is interesting to observe in this connection that some
ions may be correctly represented by the same chemical
symbol and yet show different colours and other proper-
ties in solut'on. Both the manganate ion and the per-
manganate ion are represented by the symbol ^MnOj,
yet one is green and the other pink. The copper
ion again is blue when in the cupric state, but colour-
less in the cuprous state. This is explained by saying
that the electric charge associated with the ion is
different in the different states. A well known and
simple experiment in illustration of the above views may
be made as follows : Dissolve some dry cupric chloride,
which is brownish yellow, in a very little water ; the
solution appears green. Dilute it, and it becomes blue ;
add a strong solution of hydrochloric acid or sodium
chloride and it turns green again. Repeat the latter part
of the experiment, using mercuric chloride instead of sodium
chloride, and the solution remains blue. The "ionic"
explanation is that the very strong solution first made

contains some molecules of cupric chloride (impure
yellow) mixed with copper ions (blue) and tliis mixture
gives to the eye the appearance of green. On diluting,
the cupric chloride molecules are further ionised, giving
therefore less yelk)w and more blue. If, however, a
strong solution of a metallic cliloride is added, its chlorine
ions, being in great concentration, prevent the further
ionisation of the cupric chloride, according to well known
principles which will be discussed later. It happens,
however, that mercuric chloride is an exceptional salt in
that it is only very slightly ioniseil when it is dissolved in
water; there are scarcely any free ciilorine ions in its
solution therefore, and it can have little influence in
checking or reversing the ionisation of the cupric chloride.

The colour-changes of the indicators which are used
in analysis, such as litmus, may be explained in a similar
way. We may regard these indicators as behaving like
very weak acids and the colours they show in acid solu-
tions, where they are very little, if at all, ionised, is the
colour of the compound or molecule — red in the case of
litmus. But now on adding an alkali a salt is formed,
and this, like nearly all salts, is highly ionised in solution,
so lliat we now see the colour of the acidic ion — blue in
the case of litmus. The colour-changes of other well-
known indicators can be similarly explained ; in phenol
phthalein the molecule is colourless, tlie acidic ion pink,
wOiereas in the case of methyl-orange the molecule is
pink and the acidic ion yellow.

rrhis very simple and attractive cxphuiation of the
colour-changes in indicators has, it must he confessed,
received rather a severe " shaking " owing to certain
recent observations, and it is probable that the effects
depend rather upon changes of constitution in the indi-
cator.!

Not only th^ colour but the reactions of a solution of
a salt are considered to be due to its ions; a solution of
ferrous, or ferric chloride, for example, gi\es a precipi-
tate with alkalis due to the iron ion and a precipitate
with silver nitrate due to the chlorine ion. Potassium
ferrocyanide, however, gives no precipitate with alkalis,
although it contains iron, and chloral gives no precipitate
with silver nitrate although it contains chlorine. The
potas-iuni ferrocyanide contains its iron associated with
cyanogen as a complex group, and when dissolved gives
potassium ions and ferrocyanide (l'eCr,N(,) ions; none of
the iron, as such being present in the ionic state. Cliloral
again gives a solution which contains no chlorine ions ;
the chlorine is combined with the other elements as an
undissociated molecule.

Mercuric cyanide has long been known as abnormal in
its behaviour, since it answers scarcely any of the usual
tests either for mercury or for a cyanide. It can he shown
in \arious ways, however, that the salt is practically dis-
solved unchanged ; its solution contains neither mercury
ions nor cyanide ions. The poisonous character both of
mercury salts and of cyanides is assumed to be due to
their ions ; therefore we should expect mercuric cyanide
to be non-poisonous. This is stated to be the case,
although it does not appear that any ardent supporter of
the " ionic " theory has had the strength of mind to try
its effects upon himself.

The most "chemically active" substances then in
solution are those which are most ionised. It does not
follow, how^ever, that all chemical changes which may
take place in solution are necessarily ionic changes. It
has been shown, for example, that certain salts and acids
undergo immediate double decomposition when dissolved
in solvents in which no ionisation occurs.

The action of a strong acid upon the salt of a weak
acid was formerly looked upon, as indicated above, as

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

due to the strong acid appropriating the base and turning

the weaker acid out. For example —

Sodium acetate + hydrochloric acid = sodium chloride +

acetic acid.
But the ionic view is quite different. Here we assume
that sodium ions + hydrogen ions + chlorine ions +
acetic ions give sodium ions + chlorine ions + slightly
ionised acetic acid, the change consisting in the union of
hydrogen ions with acetic ions, the others remaining
unchanged.

It is well known that many salts which are "normal "
in the chemical sense yet give an acid or an alkaline
reaction \vhen dissolved in water. Thus sodium borate
or sulphite shows an alkaline reaction, whereas aluminium
sulphate or ferric chloride react acid. This may be ex-
plained by assuming that the salt is partly hydrolysed by
water in the first instance, giving acid and base in equi-
valent quantities. But if the base is strong and the acid
is weak the former will be largely, and the latter slightly,
ionised ; so that the solution will contain an excess of
hydroxyl over hydrogen ions, and will therefore react
alkaline. If the base is weak and the acid strong, there
will, for similar reasons, be an excess of hydrogen over
hydroxyl ions, and the solution will be "acid."

Many of the ordinary chemical changes may be repre-
sented as consisting in an exchange of electric charges
between the ions, or in the assumption of charges by
neutral substances whereby they become ionic, and a
corresponding loss of charges by the ions whereby they
become " ordinary " or neutral substances. When dilute
hydrochloric acid acts on zinc, for example, the metal
passes into the ionic state, assuming positive charges ;
whilst the ionic hydrogen gives up its positive charges,
liecoming ordinary hydrogen gas, the chlorine remaining
in the ionic state throughout. When stannous chloride
is converted in stannic chloride, in solution, by chlorine,
the change may be regarded as consisting in the assump-
tion of two additional positive charges by the tin ion and
the assumption of two equal and opposite negative charges
by two atoms of neutral chlorine, which thereby becomes
ionic. In this action the tin is said to change its valency
from two to four (;.f., from the stannous to stannic form),
the valency, in fact, being in this sense measured by the
number of unit charges with which the atom is associated
when in the ionic condition.

Modern Cosmogonies.

VIII.— Protyle: Wha.t is it ?

The la.te Mr. H. C. FYFE.

1 1 is with the deepest regret that we have to record
the death of one of our contributors, Mr. Herbert
Fyfe. Mr. Fyfe was only thirty years of age, and
his death, though not entirely unexpected, was
none the less sudden. He leaves a gap in scientific
journalism that none can fill as well as he. Pos-
sessed of extraordinary industry and energy, and
gifted with a quite unusual capacity for assimilating
the mam details of the matter in hand, he wrote
articles on many subjects besides the one which
was his chief interest — " Submarine Warfare " —
and his work never missed its mark. The loss to
scientific journalism is great; but the loss to his
wide circle of friends is irreparable. One of the
kindest and most generous of men, one of the most
helpful of colleagues, he leaves behind him a
memory not alone of goodness of heart or sound-
ness of mental fibre, but of a moral nature that was
a great example of courage and sweetness.

By Miss Agnes Clerke {Hon. Mem.), F.R.A.S.

The notion of a primordial form of matter meets us at
every stage of cosmogonical speculation. It is the out-
come of an instinctive persuasion that, if we could only
" lift the painted \e\\ " of phenomena, the real business of
the universe would be found to be proceeding in the
background, on a settled plan, " without haste or rest ;"
that uniformity is fundamental, diversity only inciden-
tal ; and that the transformations of the one simplified
substance might be represented by a single formula, the
discovery of which would place in our hands the master-
key to the locked secrets of the universe. Among
untutored thinkers, some familiar kind of matter, idealised
and generalised, commonly stood for the typical world — ■
stuff". Water was the first favourite. Thales, the "wise
man " of Miletus, procured his Cosmos by precipitation
from an aqueous solution, and many savage tribes have
de\ised analogous expedients. Anaximenes preferred
air for the universal solvent ; Heracleitus substituted
fire, and set on foot a scheme of what is now often
designated " elemental evolution." From the perpetual
" flux of things," he conceived that the four substances
selected by Empedocles as the bases of Nature were not
exempt ; and a fragment of his scheme survived in
Francis Bacon's admission of the mutual convertibility
of air and water. In the main, howexer, the author of
the " Novum Organum " adhered to the Paracelsian
doctrine of an elemental triad,- while rejecting the saline
principle, and retaining, as the material substratum,
sulphur and mercury. f

These twilight fancies faded in the growing light of
chemical science ; yet the mental need that they had
temporarily appeased survived, and had somehow to be
satisfied. An " Ur-Stoft " was still in demand ; but the
nineteenth century characteristically attempted to supply
it by weight and measure. Dalton's combining equiva-
lents afforded the warrant for Prout's hydrogen hypo-
thesis. The problem to be faced was to find a unit-atom
by the varied combinations of which all the rest of the
chemical atoms might be formed. The condition indis-
pensable to be fulfilled was that their weights should be
exact multiples of that of the unit, and it came near to
fulfilment by the hydrogen-atom or semi-atom. It was,
nevertheless, a case in which approximate agreement was
of no avail ; the adverse decision of the balance finally
became unmistakable ; and Prout discreetly fell back, in
1831,1 upon the resource of deriving hydrogen itself
•' from some body lower in the scale." His hypothesis, in
short, dissolved into a conjecture. It had only emphasised
the stipulation that the " Protyle" of the ancients must
be sucli as would likewise serve for the unification of all
the chemical species.

Meanwhile, the theoretical search for it had been
carried on in widely different fields of inquiry. Laplace's
speculations, Herschel's observations, had led to the con-
ception of some kind of " fire-mist" as the genuine star-
plasm. But its nature and properties remained indefinite,
or were assigned at the arbitrary choice of adventurous

' First introduced by Basilius Valentinus. See Fowler's Novum
Orgiiinim, p. 57C. note.

t Thus recurring, as Mr. I'owler remarks (loc. cit.), to Geber's
earlier view.

I Dut of Nalioiuil Ihoj^Viiplty, V I .\L\'I , p 426.

M.A

1904.J

KNOWLEDGE & SCIENTIFIC NEWS.

cosmogonists. So the " shining fluid " of space was
"everything by turns and nothing long," until Sir
Wilham Muggins, in 1S64, o'l^'^^' 't spectroscopic indi-
viduality. The " recognition -mark" of nebulium is a
vivid green ray, by the emission of wliich it is known to
iiave a concrete existence, ^'et th,' little that has besides
been learned about it discountenances its identification
with the mattria informis of anti(iue philosopliy. This we
should e.xpect to be the subtlest of all substances. Pro-
fessor Campbell, however, has gathered indications tliat
nebulium is denser than hydrogen. Its luiiiinosity, at
least, which is invariably associated with that of hydro-
gen, extends further in the same formations; it seeks a
lower level. The nebulium-atom is not, then, the
chemical or the cosmical unit.

This evasive entity, or something that curiously simu-
lates it, has proved to be of less recondite origin. Sir
William Crookes is amply justified in claiming the
venerable designation of Protyle for the " radiant mat-
ter " first produced in his vacuum-tubes nearly thirty
years ago. The discovery was astonishing and unsought ;
and its significance has not yet been measured. Matter
assumes the " fourth state," in which it is neither solid,
liquid, nor gaseous," under the compulsion of an electric
discharge in high vacua. At an exhaustion of about
one-millionth of an atmosphere, the manner of its transit
abruptly alters. Conduction gives way to convection.
Luminous eflects are abolished. The tubes cease to
glow with brilliant, parti-coloured stria; the poles are
no longer marked by shimmering halos or brushes ;
only a green phosphorescence is seen where the glass
walls of the receptacle are struck by the stream of pro-
jected particles. They come, with half the velocity of
light, exclusively from the negative pole, the positive
pole remaining inert. Hence the name " cathode-rays."
bestowed by Goldstein on the carriers of electricity in
highly-exhausted bulbs.

These mysterious, sub-sensible agents possess certain
very definite properties. Their paths are deflected in a
magnetic field ; they can traverse metallic films ; and
their investigation in the open, thereby rendered feasible,
has shown them to possess photographic efficacy, and
the faculty of l)reaking down electrical insulation ; more-
over, they transport a negative charge of fixed amount,
and have a determinate momentum. They are then
assuredly no mere pulsations of the ether ; unless our
senses " both fail and deceive us," their quality is ma-
terial. Material, yet not quite with the ordinary
connotation of the term. The most essential circum-
stance about the cathode-rays is that they remain un-
modified by the chemical diversities of the originating
gases. t X hydrogen tube yields identically the same
radiant matter as an oxygen or a nitrogen tube. Here
then at last ^ve hav'e within our grasp undifferentiated
substance — matter not yet specialised, neither molecular
nor atomic, matter destitute of affinities, exempt from
the laws of combination — matter in its inchoate, and
perhaps ultimate, form ; in a word, the far-sought
Protyle.

Already, in 1879, Sir William Crookes conjectured the
infinitesimal missiles propelled from the cathode to be the
" foundation-stones of which atoms are composed." i
.■\nd in 1S86 hejpronounced them more decisively to be
the raw material of atoms, which, to Sir John Herschel's
apprehension, bore the unmistakable stamp of a " manu-

• Crookes, I'bil. Trans. Vol. CLXX , p. 1O3

t J. J. Thomson, The Discharge uf Ehclricilv through Gases, p. 195 ;
Phil. Mag. Vol. XLIV. . p. jii ,

j Science, June 26, 1903.

factured article." Nor did his recent commentator re-
frain from attempting distantly to divine the method of
their construction, or from laying his linger on the by-
products and residues associated with it,' , although \\{\
felt compelled to relegate the cosmic factory to the edge
of the world, where inconcei\'al)le things may happen.
All this, indeed, seemed, in the late Victorian era, like
mounting the horse of Astolfo for a trip to the moon ; and
sane common-sense pronounced it fantastic enougli to
" make Democritus weep and Heracleilus laugh." I Hut
we have since learned from Nature hersell some tolerance
of audacities.

Step by step, the new order uf ideas has irresistibly
come to ihe front. It owed Us origin to Sir William
C'lookes's skill in producing high vacua, and the con-
secjuent development in his tubes of radiant effects.
Then, in 1879, uni\ersal importance was claimed for
them, and matter in the ''fourth state," by a revival of
the dreams of the ancients, expanded into a kind of
visionary Protyle. Philipp Lsnard made the next ad-
\ance towards its actualisation by slipping it, in 1894,
through an aluminium window, and watching its
behaviour towards ordinary matter. Two years later,
l^bntgen-rays made their entry on the scene ; and before
the end of 1896, Becquerel, hurrying along the track of
novelties, came upon the momentous discovery of radio-
activity.

A revision of ideas has ensued. Some time-honoured
assumptions have had to be discarded ; so-called laws
have been found to need ijualification ; the (jid system of
physics is consequently out of gear, and much time and
patient labour must be expended upon the adjustment of
the new and improved system destined to replace it. The
leading and indisputable fact of the actual situation is
that a number of hitherto unsuspected modes of energy
lia\e been disclosed as widely operative in Nature. All
are of a " radiant " character. They travel in straight
lines with enormous speed ; they start from a material
base, and pr(.)duce their several effects on reaching a
material goal. Now these effects are closely analogous,
notwithstanding that the rays themselves are radically
dissimilar. Those of the cathodic kind are corpuscular.
They consist of streaming particles, each, according t(j
Professor J. J. Thomson, of about one-thousandth the
mass of the hydrogen-atom. Others — the noted "alpha
rays " — are atomic ; they are supposed to aggregate into
helium. Finally, the Ii<)ntgen variety are ethereal ; they
are composed of light-vibrations reduced in scale, and
augmented correspondingly in frequency. What is most
remarkable is that these various forms oi activity gise
rise, by different means, to very much the same results.
They are, in fact, distinguishable only by careful observa-
tion. They possess in common, though not to the same
degree, the faculties of penetrating opaijue matter, of
impressing sensitive plates, of evoking fluorescence ;
while under the impact of cathode and Rontgen rays, as
well as of ultra-violet light, insulated electric charges
leak away and evanesce. There is, however, one clear
note of separation between cathodic and X-rays in the
sensibility of the former, and the indifference of the latter,
to magnetic intiuence. Thus alone, it would appear, is
electrified matter set apart from what we call ether. If
tlying corpuscles could be obtained in a neutral condition,
the distinction would vanish. But this is evidently im-
practicable. Indeed, advanced physicists abolish the
material substratum of the corpuscle, and assign its attri-
butes to the associated atom of electricity. It is, at any

* i'roc. Chem. Sociely, March 28, iSSJi.
t Times, Marcli 30, 1888,

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

rate, undeniable that the cIclUil.lI relations of matter
become more intimate as our analysis of its constitution
goes deeper. Ether, electricity, matter, all seem to merge
together in the limit; their distinctions ultimately evade
definition. So animal and vegetable life appear to coalesce
in their incipient stages, and de\elop their inherent differ-
ences with ad\ance towards a higher perfection.

The various branches of inorganic nature, too, possibly
spring from a common stock. C)ur powers of discrimina-
tion fail to separate them as we trace themdownward ;
but that may he because of the inadequacy ofthe guidirg
principles at our command. A larger synthesis is de-
manded for the harmonising of multitudinous facts, at
present grouped incongruously, or left in baffling isola-
tion, and it is rendered increasingly difficult of attainment
by the continual growth of specialisation. Year by year
details accumulate, and the strain of keeping them under
mental command becomes heavier ; yet what can be
known must, in its essentials, be known as a preliminary
to extending the reign of recognised law in Nature.

Sooner or later, however, the wealth of novel expe-
rience recently acquired will doubtless be turned to the
fullest account. Just now, we can grasp only tentatively
its far-reaching implications. They have a very im-
portant bearing on the hoary problem of the genesis of
visible things. The (juestions of what matter is, and of
how it came to be, have been cleared of some of the
metaphysical cobwebs involving them ah aniiquo, and
insistently crave definite treatment by exact methods.
We should, indeed, vainly aspire to reach — or to com-
prehend, even if we could reach — an absolute beginning.
To quote Clerk Maxwell's words : " Science," * he wrote,
"is incompetent to reason upon the creation of matter
itself out of nothing. We have reached the utmost limit
of our thinking faculties when we have admitted that,
because matter cannot be eternal and self-existent it
must have been created." The discovery that atoms
disintegrate into corpuscles does not then bring us any
nearer to the heart of the mystery ; but it is eminently
suggestive as regards secondary processes.

Acquaintance with ultra-atomic matter, begun within
the narrow precincts of " Crookes' tubes," has advanced
rapidly since " radiology " took its place among the
sciences. For, from the time when Becquerel first saw
a plate darkened by the photogenic projectiles of
uranium, and Madame Curie sifted radium from the
refuse of the mines of Joachimsthal, the lines of proof
steadily converged towards the conclusion that chemical
atoms are not only divisible, but that their decay pro-
gresses spontaneously, irresistibly, in fire, air, earth, and
water, as part of the regular economy of Nature. To
explain further. Radio active bodies are composed —
according to Rutherford's plausible hypothesis — of atoms
in unstable equilibrium. The gradual changes incidental
to their own internal activities suffice to bring about
their disruption. And their explosi\'e character is ob-
viously connected with their unwieldy size, since
uranium, thorium, and radium, the three substances pre-
eminent for ladio-activity, possess the highest atomic
weights known to chemistry. The precarious balance,
then, of each of these complex, though infinitesimally
small, systems is successively overthrown, regardless of
external conditions or environment, their constituent
parts being hurled abroad with .the evolution of an
almost incredible amount of energy. Their products
include cathode-rays; matter in the "fourth state,"
matter a thousand times finer than hydrogen, is ejected
in torrents from the self-pulverised atoms of radium.

* Ency. Brit., ait. Atom.

Moreover, the issuing rays are equivalent to currents of
negative electricity. Each corpuscle bears with it an
electron, or is itself an electron ; for the choice between
the alternatives is open. In either case, we are con-
fronted with matter apparently in its ultimate form ; and
to that form ordinary, substantial bodies tend to become
reduced. Electrons may fairly be called ubiquitous.
They occur in flames, near all very hot masses, wherever
ultra-violet light impinges on a metallic surface" ; they
are freely generated by Rcintgen and cathode rays ; they
are the agents of electrical transmission in conductors.
Everywhere throughout the universe, then, atoms are in
course of degradation into corpuscles. But no informa-
tion is at hand as to the scene or mode of their reconsti-
tution. The waste and decay are patent ; the processes
of compensation remain buried in obscurity. Indeed,
Sir William Crookes anticipates the complete submer-
gence, at some indefinitely remote epoch, of material
substance in Protyle, the " formless mist " of chaos. He
assumes an identity between the past state and the future,
leaving, however, the present unexplained. The break-
up of matter, in fact, does not render its construction the
more intelligible. Running-down is an operation of a
different order from winding-up. It is an expenditure of
a reser\e of force. It needs no effort; it accomplishes
itself. But to create the reser\-e for expenditure demands
foresight and deliberate exertion ; it implies a designed
application of power. Now each atom is a store-house
of energy representing the force primitively applied to
reduce some thousands of free electrons to the bondage
of a harmoniously working system. Its disruption is
accompanied by the dissipation of the energy previously
accumulated in it ; and that atomic systems are not cal-
culated for indefinite endurance is one of the most sur-
prising of modern discoveries. The secret of their
original construction is, nevertheless, still impenetrable.
That they are composed of Protyle — that their clustering
members are corpuscles moving under strong mechanical
control — is more than probable. And the law of order
adumbrated by what are called the " periodic " relations
of the chemical elements shows that their concourse was
very far from being fortuitous. But beyond this point,
there is no holding-ground for definite thought. \\'e are
ignorant, too, whether the process of building matter out
of Protyle is at present going on, or was completed once
for all in the abysmal fore-time, decay being now defini-
tive. Nor is it likely that we shall e\er succeed in cap-
turing with recognition a brand-new atom freshly minted
for cosmical circulation.

' Fleming, P/Df. A'l^ii/ /«s///H(f, Vol XVII., p. 169.

A Free Public Reference Library, having distincti\e charac-
teristics, is in course of formation by the London County
Council at the Horniraan Museum, Forest Hiil. The primary
intention is to encouratje the study of Geology and the biolo-
gical sciences (Botany, Zoology, and Anthropology') — especi-
ally as represented in the Horninian Museum collections — by
providing the best books on these subjects, more particularly
the works of admitted authority which, by reason of cost and
a relatively small demand, are not ordinarily found in libraries
freely accessible to the general public. Although undue im-
portance is not attached to merely descriptive works, a dis-
tinctive feature of the library is the prominence given to the
special books necessary to a detailed study of any section of
the Archa-ology or the Natural History of the British Islands.
Text-books. manuaL, and monographs are supplemented by
works on the theoretical aspects of every branch of science
with which the library is concerned, and books designed to
stimulate individual observation and inquiry, including the
most recent manuals, British and American, of " nature-
study," are liberally provided.

May, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

Animated Photographs
of PloLrvts.

Hy Mrs. Dlkini-ikld H. Scott.

The kinematograph has now been in use for many
years for successfully reproducing rapid movements of
living objects, such as the boat-race, an express train
in motion, or the Coronation procession. "Its use for
showing, at an accelerated speed, sloh' movements which

the screen and tin- spectators can liavc tlic pleasure
of seeing the earth rriisixl up by the swelling seed, the
seed-coat thrown ofi", the seed-heaves emerge, straighten
themselves out, and then the lirsl leaves burst forth.

If the plant is a climbing one such as tlie I'rench l>ean,
another plate will show the point of the stem swaying
round in large circles till it comes into contact with its
support, and twines round and round the stick provided
for it. Professor Pfeffcr, of Leipzig, in 1900, devised a
\-ery perfect apparatus of this sort for class demonstra-
tion, the photographs being taken by electric light with
a film kineniatotjraph. I'.ul the expense of this appa-

Sparmannia a.fricana.

•MiKiS

I IK. 14.

t"'S- IS-

1 1 shows the general appearance of
the inflorescence, taken at 5 a.m.
riowers just opening lr()ni the ritjht
po.sition.
Kig. 12. Photograph 10 shows bud on the left
swelling.

f-ijf. i.i.

-Photograph Ho. The bud is half open,
and the bud on the right is in the
vertical position, read> for opening.

Hig. 14. Photograph 150. ISoth flowers open.

Fig. 15.— Phot ,>graph 220. Still further open.

cannot be watched by the eye, and which last over a
considerable period of time has, no doubt, often been
thought of, but has not been put to much practical test.
In fact I know that some years ago, two eminent pro-
fessors of science visited one of the popular places of
entertainment to watch a boxing match on the screen,
with a view to obtaining hints for the use of the kine-
matograph for scientific purposes. I did not hear that
the experiment went any further.

In the plant world there are many fascinating sub-
jects possible. If photographs of a germinating seed are
taken by the kinematograph at regular intervals during
many days until the seed has germinated and sent up
its seed leaves, the photographs can be thrown on

ratus is too great for the use of amateurs, as, exclusive
of the initial expenditure, each new film costs go marks =
£^ los. I hope to explain in the following pages the
method of working a smaller and less expensive appa-
ratus, which is within the reach of the ordinary amateur
photographer.

The first plant selected for experiment was Sparniannia
africana,''- a native of South Africa well known in our
greenhouses. A photograph is given of the inflorescence
of this plant (fig. ii), which gives some idea of its general
appearance. It is a plant which belongs to the same
order as the Lime Tree, and has many attractive features ;

Annals of Botany, Vr>!. XVII.. No. LXVIII. Sept , 1903.

Figy

SparmaLnniac a-frica-na..

-10. Shows stages selected from the Kammatograph photographs in the opening of a bud.

p.g. I. Watch the bud.

Fg.

I ig .1.

fig. 4.

Fig. .■;.

Fig. 0.

Fig.

Fig. X.

Fig. 9.

Fig. 10.

KNOWLEDGE & SCIENTIFIC NEWS.

May, 1904.

the buds, which hang down round the stem, only open in
sunli,t,'ht at a temperature of not less than ahont 60° F.
26° C., the flowers shut up every night at varyin,t,' times
according to their age, opening again each morning for
several days, and each day the flower alters in appearance.
This can be seen in the drawing — the buds are hanging
round the stem — one flower is just opening; there are
two older flowers and several in an upright position
which have closed, and are about to form fruits.
Then the stamens are sensitive, and when touched move
away from the stigma. The way the flowers are arranged
on the stem is also interesting ; the buds hang down at
flrst, then move upwards during the night, and then bend
again into the vertical position before openmg as in fig. i
bud. There is a little joint or pulvinus on each flower stalk
where the bend takes place ; when the fruit is ripe a layer
of cork is formed at this joint and there the fruit is de-

differs in size. It is capable of taking 350 photographs.
When ready for use, the disc is put into the machine,
which is light proof, and by means of a handle at the
side can be rotated, so that every part of the plate
is exposed before the small oblong opening in front
of the lens and the photographs appear in a spiral
on the disc. In ordinary kineniatograph work, the
handle is rotated at a uniform speed and a series of snap-
shots are produced, but for the work now required, it is
necessary to take time exposures, as photographs must be
taken at all times of the day and in all weathers ; a large
number of photographs are only wanted when rapid
movements, such as that made by the stamens when
touched or when a bud is opening, are taking place.

For miny parts of the day a photograph taken once
every quarter of an hour is sufficient.

The practical difficulties in this kind of photography

Weather Plant lAbms prccatonus

^iiiiMiHiim fl

-J'. ■■■•

■'^4».

"';-.

%^iWI9||^ ■

•

Fig-. 22.

Fig. 23.

Fig. 24.

Fig. 22. — Photograpli. Position of leaves at
2.18 p.m.. on Marcii 31, 1P04.

Fig. 23. — Pliotograpli. Position of leaves at
5.15 a.m., the whofe rachis is
moving up, tiioiigti tlie leaves
are not yet open.

Fig. 24. Photograph. Position of leaves at
10 a.m., April 1, 1904.

Fig. 25.— Shows the night position.

Fig. 25.

tached. This plant seemed, therefore, a very suitable
one for experiment. I aimed at photographing the in-
florescence at intervals wliile young, so as not only to
show the opening of the flowers, their closing at night,
and the movements of the stamens, but also the develop-
ment of the inflorescence from bud to fruit. I hoped in
this way to show the progress of the plant during several
months in a few minutes on the screen.

My first experiments with a film kinematograph,
though successful enough to encourage me to proceed,
had many defects ; the machine was not constructed for
this sort of work, and the maker was unable to help in
adapting it. The celluloid film would not stand the
constant damp of the greenhouse, and this was only one
of the many difficulties encountered with this machine.
My most successful experiments have been with the
Kammatograph, in whicii the photographs are taken on a
glass disc instead of a film. The disc, 12 inches in dia-
meter (half of one is shown in fig. 16) is suspended in a
metal ring; it is coated with a sensitive emulsion, just
like any ordinary photographic plate, from which it only

are rather overwhelming at first, but I have now over-
come the principal ones, and think that anyone who
cares to try the experiment for himself will find it
fairly easy. The expense of each negative plate is 2s. 6d.
and the positive is also 2S. 6d., so that the total cost of
each completed kinematograph picture is 5s., plus the ex-
pense of developing. If this is done professionally, each
plate costs is. to develop, thus bringing the cost up to
7s. The developing and printing are extremely simple
compared with a film negative, as all the 350 photographs
are developed and printed at the same time and in the
same way as an ordinary plate ; this seems to me a great
practical advantage.

Two principal points must be considered : —
I. — The apparatus must be quite rigid, as the slightest
movement would spoil the whole result. Mr. Kamm has
now devised a very satisfactory stand for this purpose.

2. — Each photograph must be exposed uniformly, and,
as they have to be taken at all times of day and night,
this at first was one of the greatest difficulties. By the
use of Wynne's actinometer, this difficu'ty was completely

May, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

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KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

removed. I at first used
night exposures ; but this

r.ia,:;T.eb!u:ii
was very

laborious work.
I now use an incandescent lamp fed by methylated
spirits, but for those who are fortunate enough to
have electricity an arc lamp is best of all. When once
the right e.xposure is found all further difficulty in this
direction is removed. No doubt the ideal method would
be to ha\e a clockwork apparatus for turning the machine
which at the same time turned on the light and exposed
the plate, as Professor Pfefter has.

The Sensitive Pla.r\t. — Mimosa seusitiva.

This plant closes its leaves when touched, and also
naturally shuts them up at night. The leaf is divided
into two piniur, each divisi'^n bearing numerous leaf-
lets. The best way to make them work is to light a
match and put it under the end pair of leaflets at the
tip of one of the pinna of the leaf. The first pair of
leaflets then shut, then the second, and so on till the

Climbing Plant {Mucuna nivca"\.

Fig 29.

Fig. 20.

Fig. 28.

Figs. 26 and 27.-Pliotographs. Show the tip of the stem turning round the support.
Fig. 2S.-Photograph. Shows the same tip appearing on the other side of the support.
Shows the tip applied closely to the support.

Fig. 20. — Photograph.

whole pinna is closed ; the same stimulus then closes the
two leaflets next the stalk of the neighbouring /jwm,, and
the leaflets close one after the other till the tip of the
leaf is reached. Every leaf on the same branch follows
suit, .\fter some time the leaf-stalk falls, another leaf
closes m the same way, until the effect of the stimulus is
at an end. These photographs are taken as quickly as
possible consistent with giving the right exposure, and
require a whole plate.

A second plate shows the leaves reopening, taken at
intervals of about five minutes: the exposures were con-
tinued until the leaves shut into the sleep position for
the night.

The more common species, .1/. pudica, serve equally
well lor experiment.

The Weather ¥^\3.r\i.—Ahnts precahriiis.
There has been much discussion about this plant lately
as to whether it really predicts the weather to be expected
in the future. I have a series of photographs extending

over one complete day, whici. ......v. the regular day and

night movements of the plant. The plant was kept in a
glass case sheltered from wind and sun at a temperature
not below 73° F. = 22-5° C. The plant was placed with
the rachis (midrib) of its youngest leaf facing north. The
photograph was begun at 11.30 a.m. on Thursday, March
31, 1904, and continued until 10.30 p.m. It takes up the
sleep position at 4.30 p.m. Then the photograph was
begun again at 5 a.m. on .\pril i, while the leaves v.-ere
still shut. As the sun rises the leaflets gradually open,
and each leaf raises itself so quickly that one can watch
the movements easily.

The kinematograph seems to afford a means of defi-
nitely settling this question. The photographs give an
unbiassed record of the movements of the plant and the
weather reports, barometrical and thermometrical read-
ings, records of earthquakes, &c., can be provided by the
various meteorological stations, so that if a re-investiga-
tion is ever considered necessary after Professor Oliver's*
exhaustive report on the subject the data
could in this way be obtained.

Climbing Plants. — This is a very fas-
cinating subject for the Kammatograph.
( )ne has to focus the support on which
the plant is climbing and to keep
the tip of the climbing stem in the held.
.\s the plant grows in length the Kam-
matograph has to be raised. In showing
the photograph with the lantern a jerk
will be noticed every time this is done,
so if it can be arranged to alter the
stand every morning one can see how
much the plant has twined each day.
Anyone who takes the trouble to photo-
graph a climbing plant will be surprised
at the very curious movements of the tip.
The way in which it circumnutates, turn-
ing to every point of the compass, then
gives a twist when it comes into contact
with its support, is very fascinating.

The real difficulty with the climbing
plant is that it grows and climbs just
as much at night as it does in the day,
so that if it is not photographed at night
there is an interruption when projecting
it with the lantern corresponding to the
beginning of each new day. I am afraid
a perfect photograph of a climbing stem
will not be attained without clockwork
apparatus, as the trouble involved of sitting
up all night for at least a week would be too much to
expect, even of the most ardent photographer.

The plant illustrated is a Calcutta stem-climber,
Muciina invca. It was photographed for a week from
6.30 a.m. to 11.30 p.m.

I hope in these few pages that I may have succeeded
in interesting some of the readers of " Knowledge " in
the work of making animated pictures of plants, and
shall be only too glad if I can be of any use to anyone
who wishes to try these experiments. The illustrations
of such a subject are naturally disappointing, as they
cannot appear animated, but if anyone will take the
trouble to cut out the ten figures of the opening bud of
Sparmannia africana (Figs, i-io) and paste each on a card
or luggage label, and fasten them together closely at the
'ower end, by letting each figure pass before the eye they
appear animated and will give some rough idea of

will

what the plate will show when projected with a lantern.
• Kew Bulletin, Jan , 1890.

M.'

AY, 190;

KNOWLEDGE & SCIENTIFIC NEWS.

The ** Canals" of Mars.

A Reply to Mr. Story.

Hv K. Walter Mainiiek, I'.K.A.S.

Several correspondents having expressed a strong wish
that I should give some reply to Mr. Story's letter on
this subject, I will endeavour to do so ; not without
reluctance, as the line which Mr. Story took seemed, in
my opinion, hardly likely to advance our knowledge.

If I may briefly summarise Mr. Story's objections
to the paper communicated by Mr. Evans and myself
to the Royal Astronomical Society last June, they
come under three heads. He objects to me as the
author, to the methods employed, and to the deductions
drawn.

The first objection is of course a somewhat delicate one
for me to handle. It deals rather with the personal than
with the scientific, and I have no inclination to fill the
columns of Knowledge with detailed evidence of my
claim to be considered an " expert " on the subject of
Mars. Let it suffice that as long ago as 1877, I had
made a thorough study of the planet, using the fine
12^-inch Merz refractor of Greenwich Observatory. In
1892 and 1S94 I also used the 2S-inch Grubb refractor —
certainly one of the most perfect objectives in existence.
I give two or three examples of my earlier drawings, from

Fig. I.

-Drawings of .Mars made witli the I2,=incii Refractor of
tile Royal Observatory, (ireenwicii.

H, M.

I. 1877 September 29th 10 10
3. 1879 November 5th.. 13 5

It. M.

J877 September 241I1 11 43
lf5Sj January yth 12 2

which it will be seen that I had recorded some of the
markings now familiar to us as " canals " and " oases,"
even before Schiaparelli had published his results, and
quite a number before they had been generally recognised
by observers.

So much for the person, next for the methods. Mr.
Lowell and Mr. Story both appear to object to the

employment of terrestrial experiments to elucidate plane-
tary appearances. Mr. Lowell's opinion to tiiis effect
may be found in his letter published in the " Observa-
tory " for January, 11)04, p. .[g : '• Permit mc, in con-
clusion, to point out to you . . . that the only evidence
germane to the matter is to be got from astronomical
observations directed to that end." But as Mr. Story
points out, Mr. Lowell himself has set on foot terrestrial
experiments for the express purpose of drawing infer-
ences with respect to his observations of Mars, and Mr.
Story approves of his so doing. Kliminating what is
common to the two cases, the one of which meets with
Mr. Story's approval, and the other with his disapproval,
the only residuals are Mr. Lowell on the one hand and
myself on the other, and the statement is reduced to the
simple proposition that he approves of Mr. Lowell and
disapproves of me, irrespective of our actions. In other
words, his second objection is but a more diffuse way of
restating his first.

But to take the matter seriously, let us see prt;cisely
what is the point where Mr. Lowell's \'iews and my own
diverge. It is not in the chief markings of Mars. Mr.
Lowell sees and draws these substantially as I saw and
drewtheni in 1X77, and as Beer and Miidler drew them in
1830. It IS not in respect to the appearance of the
" canals " ; 1 observed and drew " canals " as far back as
1S77, and though of course Mr. Lowell has seen and
drawn far nion; " canals " than I have, those that I saw
were substantially of the same character as his ; and in
the discussion of this cpiestion 1 have been most careful,
both in writing and speaking, always to point out that 1
was not throwing doubt eithtrr on the fidelity or the skill
of any of the observers of Mars. Mr. Evans and myself
wrote : •' It would not be in the least correct to say that
the numerous observers who have drawn 'canals' on
Mars during the last twenty-five years, have drawn what
they did not see. On the contrary, they have drawn,
and drawn truthfully, that which they saw." (" Monthly
Notices" \'ol. LXIIL, p. 499.) Nor have I ever
asserted or assumed " that the canals are seen as very
faint lines, so faint that their existence is doubtful even
to experienced observers." 1 know the reverse by actual
experience.

We agree on a third point. Mr. Lowell is absolutely
convinced, and in this 1 am quite at one with him, that it
is not possible that an actual network so geometrical
as that which he represents can be the result nf
purely physical causes. Mr. Story has no doubt seen
the very fascinating book which Mr. Lowell published
on "Mars" in November, 1895, and has read the pages
148-154.

After this we differ. Mr. Lov/ell attributes this con-
fessedly utterly unnatural network to the handiwork
of intelligent beings who have woven over their
planet these "grotesijue polygons" to use Schiaparelli's
expression.

This, be it nijted, is inference, not observation ; and an
inference which demands the assumption that, were i\Iars
brought much nearer to us, or our power of seeing greatly
improved, these grotesque polygons would still persist,
and would never resolve themselves under better seeing
into markings which we could reasonably ascribed to the
unaided processes of Nature.

My inference is different; the unnaturalness may be
due to the imperfection of our seeing. I rely on well-
known facts respecting the theory of vision and the
structure of the eye, and the eye is our necessary instru-
ment for observation. We have no right to resort to the
unknown and the artificial, before we have exhausted

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

the known and natural methods of explaining a pheno-
menon. My inference is one based on the observed
effects of known causes; Mr. Lowell's inference is an ex-
cursion into fairyland.

We know that the smallest single dark marking on a
bright ground which can be seen by an observer of per-
fect sight, without optical assistance, must have a
diameter of at least 34 seconds of arc. This diameter
depends upon the size of the rods and cones of the eye
which receive the visual impression, and compose the
sensitive screen. It is therefore an inevitable limit. .\s
this diameter is necessary for the object to be merely
perceived, or, in other words, to create any sensation at
at all, it follows that in order that the actual shape of the
object may be recognised, its diameter must consider-
ably exceed this limit, otherwise it will be seen as a truly
circular dot, whatever its actual shape.

This is the case for small isolated markings just
within tlie limit of visibility. The case is different for
extremely elongated markings ; the increased length of
a marking will compensate for diminished breadth up to
a certain limit, but not beyond it. For a Ime of indefi-
nite length the limit of breadth approaches two seconds of
arc. A line of a breadth below one second of arc is
invisible, no matter what its length ; but it must have a
breadth many times this amount before it can be seen as
anything else than a mere line — before irregularities in
shape and breadth can make themselves apparent.

In naked-eye vision, therefore, there is a considerable
range within which small objects, whatever their true
shape or nature, can only be seen as dots or as lines.
The result is that these two forms are certain to come
in evidence whenever we are dealing with objects too
minute to be fully and properly defined.

The problem becomes more complicated when we are
using optical assistance, as there is a limit of definition
belonging to the telescope as well as to the eye. But
the principle remains the same ; the result of adding the
limitation of the telescope to the limitation of the eye
being that the actual magnification of the telescope can
never be nearly as effective as it is nominally. A power
of 300 on the best telescope in existence, and under the
best atmospheric conditions, would never show the
features ot the moon as distinctly as they would be seen
if the moon were brought 300 times as near.

Mr. Story and Mr. Lowell both object that terrestrial
(or, as they are more usually called, " laboratory ") expe-
riments are altogether beside the mark when applied to
the interpretation of astronomical observations. The
contention is a ridiculous one, and if logically applied
would render it impossible to determine the instrumental
errors of a transit circle by the use of meridian marks,
collimators, or mercury trough, or the personal equation
of an observer, except by actual stellar observation.
They would also foibid us to identify the lines of solar
or stellar spectra by comparison with those of any terres-
trial element.

Hut since it is contended that Mars alone can give us
valid information on the subject, to Mars let us refer.
If we turn to the drawings made by Beer and Miidler in
1830, two small objects exceedingly like one another
appear repeatedly. These are two dark circular spots,
the one isolated, the other at the end of a gently curved
line. Both recall the "oases" which figure so largely
in many of Mr. Lowell's drawings, and the curved line
at the termination of which one of the spots appears, is
not unlike the representation which has been given of
several of the " canals." There can be no doubt that in
the year 1830 no better drawings of Mars had appeared
than those to which 1 have referred, and that in

representing these two spots as truly circular Beer and
Madler portrayed the planet as they best saw it. The
one marking we call to-day the Lacus Solis, the other the
Siinis Siihifus, and we can trace the gradual growth of our
knowledge of both markings from 1830 up to the present
time. The accompanying sketches of the same region

'/^

^ *

Fig. 2. — Sinus 5aba;us and Lacus Solis.

Sinus Sab.-eus

Lacus Solis

Beer and Miidler i»30.
Lockyer . . 1862.
SchiapareMi . . 1890.
Beer and Miidler 1S31.
Lockyer .. 1S62.
SchiaparcUi .. i8go.

by Lockyer, in 1862, and by Schiaparelli, in 1890, illus-
trate well how the character of the markings revealed
themselves with increased telescopic power and experi-
ence in the observer.

•' At first it seemed a little speck
And then it seemed a mist,
It mo\ ed and moved and tooli at last
A certain shape I wist.

A speclv, a mist, a shape."

If Beer and Madler, in 1830, had argued that the precise
circularity of these two spots, as they appeared to them,
was proof that they were artificial in origin, would they
have been correct? Would not the answer have been
valid that a spot too" small to be defined must appear
circular, and that, therefore, the apparent circularity pro-
bably covered detail of an altogether different form ?
We know that it would. Yet it is that same argument
in a far stronger form against which Mr. Lowell and
Mr. Story are contending to-day. Beer and Madler only
drew two of these spots ; Lowell shows over sixty.
Beer and Madler's two spots seemed to them precisely
alike; how utterly different those two spots appear to us
to-day the diagram may serve imperfectly to indicate.
Mr. Lowell's sixty or more " oases," with one or two
exceptions, appear all of the same character. Will any-
one dream that if the next seventy years brings telescopic
development equal to that shown in the last seventy, the
present uniformity of Lowell's "oases" will persist, any
more than the likeness of the two spots observed by Beer
and Madler? We need not even wait for the seventy
years. Up to the present moment I have carefully
avoided anything like criticism of the drawings of any
observer of Mars. I have repeatedly stated that I ac-
cepted them as being both faithful and skillul representa-
tions of what the observers saw. Ijut it is necessary
here to point out that the extreme simplicity of type of

May, 1904.]

KNOWLEDGE c<t SCIENTIFIC NEWS.

both "canals" and "oa<:es," as sliown by Mr. Lowell, is
not conriniied by the best obser\ers. In tiie last number
of " Kniiwi.epgk " Mr. Denning writes (p. 67) : " There
are really many distinctions in the canal -like markings ;
some of them are (juite broad and ditTused shadings,
while others are narrow, delicate lines." The Rev.
T. E. Phillips has recently insisted strongly (" Monthly
Notices," \'ol. LXI\'., p. 40) on the same fact, and 1
could increase the testimony indefinitely. There can be
no doubt that the best observers not merely agree in
stating that the "canals" differvery widely in their charac-
teristics, but they also agree closely in the characteristics
they assign to special "canals." With regard to I-owell's
observations 1 can, of course, speak only with reference
to those which he has published, but speaking with re-
ference to these there can be no doubt that he fails to
e-xhibit that wide variation in character between cer-
tain "canals" upon which these and other leading
observers are fully agreed. This seems to me clear
proof (so far as his published drawings go) not of superior
conditions and skill -on Mr. Lowell's part, but of
a most marked inferiority in one respect or the
other. Whether it be the location of his observatory
that is at fault, or the definition of his telescope, or his
own personal skill in observation, or most probable of all,
in delineation, the fact remains that- -despite the multi-
plicity of his observations and the perseverance, which
cannot be too highly praised and too fully recognised,
with which he has observed Mars in season and out of
season — he has failed to record difTerences apparent to a
consensus of other first-rate observers. Especially he
has failed to recognise what Denning and Schiaparelli
had recognised as early as 1884, that many of the
" canals " were very far from being straight lines of
uniform breadth and darkness, but showed evident
gradations in tone, and irregularities occasioning breaks
and condensations here and there. Of all the thousands
of drawings of Mars which I have examined, those that
most perfectly corresponded to Mr. Lowell's were the
work of a young novice and were made in by no means
an ideal station, using a small home-made telescope.

It is made an argument in favour of the actuality of the
" canals " that they have been seen with such distinct-
ness, or with such frequency. The argument is based
upon a very complete ignorance of the appearance of the
fictitious "canals" observed in the experiments made by
Mr. Evans and myself. I have myself been completely
taken in by a little drawing on which the Syrtis Major
and Sinus Sabseus were shown. As I looked at it by
far the most insistent feature was a straight, narrow,
intensely black line corresponding to the Phison. Yet
that astonishingly vivid impression was really due to the
integration of two or three feeble lines, irregular, broken,
and serpentine curves, and half a dozen utterly invisible
dots. If I had looked at that drawing a thousand times,
or if a thousand other observers had examined it under
the same conditions as to distance, they could only have
seen what I saw — a dark, straight line, as sharp as if cut
by a graving tool.

The change in the distinctness of the "canals," con-
sequent on the progress of the Martian seasons, was no
discovery of Lowell's; the fact was realised by Schiapar-
elli very early in his observations. But so far from
rendering it more probable that the "canals" indicate
artificial water-ways, it affords a most serious argument
against their having that character. For water cannot
flow uphill, yet the water from the melting polar snow,
according to Lowell, must flow upwards to reach the
equator. If, with Lowell, we consider the dark markings
on Mars to be vegetation rather than water, they would

change in appearance with the seasons whether they were
of natural origin and irregular shape, or were artificial and
symmetrical; and Mr. Lowell's S500 ohser\ati()ns do not
increase the probability of his theory more than 85 or Hh
would do. .\ " canal " or an " oasis," if seen only as a
straight line or a circular dot, that is lo say, if seen only
in the simplest possible form, affords no proof that the
precise form under which it appears has any actuality.
It is only when the object begins to show detail that we
are sure that we are beginning to sec it as it is. And one
of the most convincing testimonies that Mr. ICvans and
myself have been following the right line has been shown
by the attitude which the most experienced observers of
Mars have adopted towards our intjuiry. They have
claimed, as Mr. Denning did in last month's " Know-
i.EDc.E," that certain "canals" are undoubtedly real, for
they have been resolved or partially resolved into minuter
details, being "composed of small, irregular condensa-
tions." Others they have admitted may be "canals"
only in appearance, being actually either " the edges of
half-tone districts or the summation of very minute
details." In both the claim and the admission they are
in perfect accord with the position held by Mr. Evans
and myself. On the other hand, Antoniadi, Bariiard,
Denning, Molesworth, Stanley Williams, have all held
themselves aloof from the bizarre delineations and yet
more bizarre theories which Lowell has promulgated.
Most striking of all, Mr. W. H. Pickering, who preceded
Mr. Lowell in his argument that the water supply in
Mars is restricted, and in the recognition of the system of
" oases," who further has had the opportunity of observ-
ing with Mr. Lowell's telescope and in the climate of
Arizona, has not only frankly accepted our position, but
has supported it by direct photographic proof. Mars,
unfortunately, does not lend itself to photography, but
the Moon does; and Mr. Pickering has found confirma-
tion of our experiments as to the building up of straight-
line systems from imperfectly seen details by comparing
his drawings of certain lunar formations with actual
photographs.

Stimulus and Sensation

By J. Reynolds Green, Sc.D., F.R.S.

If we contemplate the enormous variety of form and
structure which we find to exist among plants, and en-
deavour to study the reasons which we can readily trace
for the diversity in these respects, the conviction is
forced upon us that the story which is hidden there is
one of stress and struggle, the result being a correspon-
dence between the plant and its environment, so that
the former can take advantage of all that is offered to
it by the latter, and can resist successfully such dele-
terious influences as are inevitable from its situation.
Hence different environment entails different structure.
Moreover, as the en\ironment is continually changing
in some respect or other, the organism is continually
involved in the struggle to adjust itself to the alterations
thus besetting it. in the absence of power to maintain
satisfactory relations, the plant becomes unhealthy, and
after a time it perishes. Health, indeed, is but the ex-
pression of a satisfactory equilibrium gained and main-
tained between the plant and its surroundings.

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

As we cannot deny the extreme probability, perhaps
we may say the certainty, that all plants now living have
been descended from some primitive form, we can find in
the history of different races the enormous effects which
long-continued struggle for successful adaptation to a
changing environment can achieve. The effect of change
upon a single individual may be, indeed, must be, slight ;
but long-continued influence upon long series of descen-
dants brings about a marked ctunulative effect, and
though we see little change in a generation, we are obliged
to admit relatively enormous modification in the course
of time. But though we can see little alteration in the
individual, we may argue backwards and realise that no
great change could occur in a race except by modifications
of successive indi\'iduals of it. We must, therefore, look
minutely to the individual to see what the properties are
which in long years can effect such modifications of both
form and structure as we find.

We have then to study what we may call the adapta-
tion of the organism to its environment. At the outset,
we must admit that such adaptation can take place only in
two ways. Possibly, all plants whose constitutions are
not in harmony with the changed conditions will perish,
leaving more fortunate ones to carry on the race.
This postulates that the plants of any particular genera-
tion are themselves varying slightly in their physiological
properties. Possibly, on the other hand, the individual
organism is possessed of a power of appreciating changes
in its surroundings and of modifying its own behaviour
accordingly. It may well be that both these hypotheses
are to a certain extent true, and that they are co-operating
to bring about the results we see.

There are strong grounds for accepting the latter of the
two views as playing a very prominent part in the
changes of the past. We can see certain phenomena
occurring under our own eyes which are capable of in-
terpretation in the way suggested, which, indeed, are
inconsistent with any other hypothesis. A plant acted
upon by a certain definite external influence modifies its
way of behaviour in an equally definite manner. It is
difficult to deny to the plant the power of perceiving the
influence brought to bear upon it. The effect of the in-
fluence is technically called a stimulus, and the percep-
tion of a stimulus by the plant is known as a soisatioii.
We have two factors then to consider, one external, the
other internal, to the plant.

A more complicated question arises here. Is the percep-
tion of a stimulus, is a sensation, to be interpreted as
implying any kind o{ consciousness ? We have a stimulus,
we have a response. What can we say of the interpreta-
tion of the one by the plant which makes it bring about
the other ? The problem is very difficult to speak with con-
fidence upon in the present state of knowledge. The
human mind shrinks at once from taking the affirmative
view. No doubt, in the higher sense in which we interpret
the word, no consciousness can have part in a vegetable
organism, for this sense implies ihuus^ht. It is difficult
to suggest that a purposeful response implies any kind of
volition. These operations are the immediate functions
of the well-organised and most highly-developed nervous
centres of the highest animals. But certain facts can be
adduced which, at any rate, hint at the existence of such
a limited consciousness as implies an appreciation of the
nature of the surroundings.

To discuss this question at any lenj^th would, however,
take us beyond the purpose of this article. We must
confine ourselves to the question of stimulus and sensation
as far as we can see them both at work in the course of
ordinary vegetable life, leaving the full interpreta-

tion of the relation between them to be set aside for the
present.

The nature of a stimulus first concerns us. We may
take it for granted that there may exist for every plant,
at any rate theoretically, a condition of adjustment when
it is in absolute harmony with its environment — when
temperature, illumination, moisture, rest, and whatever
else affects it, are perfectly as the organism wants them,
and when consequently its life is lieing regulated to the
utmost advantage. Such a condition can be only
momentary in any case, for the surroundings are in a
constant state of change in many of these particulars, and
the living substance of the plant is also exhibiting con-
tinual motility. For the maintenance of health, or even
of life, it is essential that variations in the one shall be
adequately responded to by variations in the other. The
impossibility of securing indefinitely such a continual
adjustment of relations is the cause of the cessation of
life.

Such an alteration of the environment constitutes a
stimulus. It may affect the plant in a hundred ways,
causing various methods of response, and various degrees
of intensity of response.

There are, however, other factors influencing its
life which are not so easily realised by observation.
Changes may arise in the condition of the living sub-
stance of the plant, set up perhaps by disturbances in its
interior. The normal cause of chemical change associated
with the nutritive processes may undergo a marked change
in consequence of an alteration of the distribution or the
direction of the stream of food in the plant's interior.
Injury to the body of the plant may involve a re-distribu-
tion of energy or of material within it, which may have
far-reaching effects upon the course of the vital processes.
Variations in the supply of food, which may range be-
tween absolute starvation and over-engorgement, may
produce very great changes not only in the outer life of
the plant, but in the substances it produces in the course
of its nutritive processes, and in the energy which it
liberates. An insufficient supply of oxygen may provoke
an almost entirely new series of chemical changes in
connection with the production of such energy. These
various factors and many others which might be quoted
are to. be regarded as stimuli, some of them internal no
doubt, but all equally real and equally well appreciated
by the plant as the more obvious external ones just de-
scribed. Even more obscure stimulations may arise
from chemical changes in the living substance itself,
leading to a series of responses which, as they do not
appear immediately related to \isible stimuli, are often
called automatic.

To appreciate more fully the part played by stimulation
in the life of a plant, we may briefly consider a few of its
more obvious forms. Consider the lateral incidence of
light upon a growing seedling or young plant. If the
latter is placed so that one side of its stem is more bril-
liantly illuminated than the opposite, a curvature soon
appears in the part that is actively growing. This is of
such a nature and takes place to such an extent as to
cause the axis of the plant to take up a position in which
it is parallel to the direction of the incident rays. It
manifests itself in some cases very slowly, in others com-
paratively rapidly. This response to the stimulus of un-
equal illumination on its two sides is not confined to the
stems of seedlings, but may be seen to a greater or less
degree in parts of many adult plants. It is a matter of
common observation that geraniums grown in a windoAv
all bend their steins and petioles towards the illuminated
side.

May, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

In other cases the same stimulus may be responded to
in quite a diflerent manner. When certain younf^ roots
are exposed to it they curve so as to place themselves in
the same position with regard to the incident rays, but
with their growing apices in the opposite direction.
\"arious tendrils, peduncles, and other organs respond in
a similar manner. Leaves tend to place themselves
across the incident rays.

Among the obvious difficulties which beset the course
of a root in making its way through the soil is that of
impinging more or less directly upon some particle which
it is unable to displace. In practice it is nearly always
found to be able to grow past such an obstacle. The
situation affords us another example of stimulus appre-
ciated and responded to. Contact with the apical portion
of the young root causes an immediate departure from
the straight line of growth. The behaviour of the organ
can be studied on a germinating bean with great readi-
ness. If such a structure be kept in moist sawdust till
the young root emerges, then be transferred to a moist
chamber and suspended therein, a small piece of hard
substance, such as card-board, can be attached by
a little cement to the side of the lip. The root at once
begins to curve away from the side thus touched, and if
the stim.ulation is maintained for some time the resulting
growth will cause the root to grow into a loop. If a
tendril of Passi flora gracilis have a small loop of thread
laid upon a certain portion of it, it will curve at once and
in about two minutes will assume the form of a helix.
Other tendrils behave in a similar way on coming into
contact with different hard supports, though the rapidity
of their response varies considerably.

The nature of the response must, however, be con-
sidered before we can associate it in any co-ordinated
fashion with the stimulus. Such co-ordination between
the two must be put in evidence if we may fairly deduce
such an appreciation as we can call sensation.

The first thing that strikes an observer is the evident
purposeful character of the response. The position
assumed in relation to the incidence of the lateral light is
that which will ensure an equal illumination of the sur-
faces of all the leaves. These spread out at approxi-
mately equal angles with the stem in all its sides, and
hence w^hen the stem is parallel to the light source the
greatest amount of sunlight falls upon the green surfaces
of the plant, where the work of forming sugar under the
influence of such light is taking place. The opposite
effect produced upon roots is calculated to press them
closely into the soil, where their absorbing hairs can have
free play. The curvature of the tendril assists it to
secure a holding for the plant, so that its weak stem
escapes being trodden down and its leaves are enabled to
reach light and air.

A less obvious consideration is afforded by the fact
that the parts of the plant receiving the stimuli are in
cases strictly localised. The receptive part of a root is
just behind its apex ; that of a young seedling stem is in
about the same position. Not only is this part localised,
but it is situated in quite a different part from that which
effects the movem.ent. The latter is caused by grov.-th
some half-inch or so nearer the base, at a part which is
quite insensible to stimulation.

Another consideration which bears upon the question
is that an extremely small stimulus is able to bring about
a very considerable effect, and that there is no simple
ratio between the intensity of the stimulus and the extent
of the response. An instance of this is afforded by the
behaviour of the tendril of Passiflora already described.

We can, therefore, associate stimulus and sensation and
point to the response of the plant as evidence of both.

Saturn.

.At the beginning of May Saturn rises 2i hours before the
sun .ind telescopic observation may be renewed, tliouf,'h the
planet will scarcely be far enoiif^h west of the solar orb to be
presented under very satisfactory conditions. The ensuing
apparition of this attractive object is likely to prove of great
interest. His southern declination will he 3' less than it was
last year and this ought to bring about an improvement in the
definition.

In the summer of igoj Saturn displayed the evidences of
considerable activity in a niunber of bright and dark spots, of
irregular form, distrihntcd in about N. lat. 35' along the polar
side ofthe northern equatorial beU (" Knowleoge," Dec. iy03).
In June, July, and Augnst these markings were frequently
seen, though but few observers appear to have retained them
in view during the autumn mouths. The rotation period of
the chief spot or spots was variously determined as follows :—
Observer or Period. Days of We«<5rence. -^

Authority. li. 111. Observation. ,>> . v

K.Graff .. 10 39 o' 3 , ^5«. >^''* 3S830t V^ V

J. C. Sola .. 1038-4 3f-. ^5£.. JVac/i. 389ij<\\ T

" - ■ 10 380 18' .-• ■ -Sj V V^

10 38-8 ' 40 ^5<.j;aj(ii\547. ^,v

P. Fauth
'E. E. Barnard

L. Brenner . .

10 38-0
h. in.

H. W. Wilson 10 38 4iS|a\>'7S!' ^'^.?^^^'; '°^

•(;. W. Hough..
•G.W. Hough..
tW. F. Denning

10 38 27'
10 38 30'5
10 37 56 4

24^'

129

l^ilIihNot. Dec, 1903.
Monthly Not. Dec, 1903
Monthly Not. Jan., 1904.

* In these cases the identifications were uncertain and the resulting periods
probably excessive.

f Mean value derived from observations of i8 spots.

As soon as Saturn can be successfully examined it will be
important to ascertain whether the markings continue percep-
tible. Possiblv, at the present time, the northern hemisphere
shows nothing'more than the beautifully symmetrical belts and
zones which usually stripe the disc. The material of the
differently tinted irregularities seen in 1903, which proliably
resulted from extensive eruptions affecting the atmospheric
scenerv, may have amalgamated with the ordinary bands of
the planet and quite lost their distinctive outhnes. And the
region affected mav remain (juiescent for a time to be again
disturbed by further outbreaks in the near future. The phe-
nomena occurring on Saturn are, no doubt, very similar to
those visiblv taking place on Jupiter, and observation has
taught us that on the latter planet one disturbance scarcely
subsides before another forces itself into prominence. The
spots common to certain latitudes of Jupiter possess some
physical resemblances, and are characterised generally (though
not invariablv) by nearlv identical rates of motion, according
to the longitudinal current in which they are placed. The
same thing is likely to be displayed on Saturn, and the few
following years may be expected to furnish useful evidence on
this point.

The spots on Saturn remained fairly conspicuous objects m
December, 1903, and observers will probably redetect them
during the present spring. If so, it will be desirable to obtain as
many transits as possil)le, 90 that the individual objects may
be satisfactorily identified and their periods of rotation rede-
termined. ,•,.,, r ,.

The markings referred to certainly exhibited some of the
vagaries which occasionally affect the features on Jupiter, for
the rate of their motion underwent a decided acceleration at
the close of the apparition. Several of the principal objects
which, during the summer, gave a period of lohrs. 38 ruin. 3 sec.
conformed witli a shorter period of 10 hrs. 37 min. 50 sec.
during the latter part of the autumn.

In regard to Saturn, the year 1903 will be remembered as
one of considerable historic interest, for the rotation of the north
temperate region was found to be 235 minutes greater than that
derived by Professor Hall from his equatorial spot of 1876,
and the fact rendered conclusive that this planet, like Jupiter,
displays atmospheric spots affected by large proper motions.

Mr. Crommelin's " Ephemeris for Physical Observations of
Saturn. 1903-4" {Monthly Notices, December, 1903) will be
found extremely useful in the further study of this interesting
object. w. F. Den.ning.

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

The Do\ible

Stereoscopic Projection

of the Eight-Cell.

By G. H. Bryan. Prof. Sc. D., F.R.S.

In connection witli Mr. Benham's paper on " The Super-
Solid," it will be noticed that the diagrams of pairs of
connected cubes, even when seen through a stereoscope,
fail to convey the impression of being the projections of
a regular figure.

A much better idea of the regular character of the
" super-cube " or "eight-cell," as it is called by most
writers, and of its connection with four-dimensional
space can be acquired by choosing the jilane of projection
in such a way as to give the dia^jram a more symmet-
rical form, and by using two different stereoscopic pro-
jections instead of one.

space containing the first, second and third dimension,
the other view^ represents the aspect of the same " eight-
cell " projected in a space containing the first, second
and fourth dimension.

Either of the two aspects shows a solid figure, which
is symmetrical but not perfectly regular. It is not difficult,
however, to convince oneself that the four-dimensional
figure of which the two aspects are simultaneous projec-
tions is regular.

In regard to the fact that in either view two of the
vertices (not the same two) appear inside the solid pro-
jection, a comparison of the two aspects will show that
they are not really inside, but only look so owing to the
direction of projection. This property is exactly analo-
gous to the fact that if we draw the trace of a cube by
projection on a plane, the projections of two of the ver-
tices will be inside the polygon formed by the projec-
tions of the remaining vertices. It is only when the
cube is viewed as a solid, or studied by means of its pro-
jections on different planes, that we become aware that all
the vertices he on the boundary of the cube.

-A. complete account of the regular figures possible in

In the anne.xed series of diagrams the central figure
represents a symmetrical plane projection of the " eight-
cell." It is not the only projection which is symmetrical,
but it is a convenient one in which the edges and sides
are well separated, and are nowhere near overlapping in-
conveniently.

When this figure and the figure to :he left of it are
viewed together through a stereoscope, the fines will
stand out in relief, giving the impression of forming a
solid figure in w'hich the point H is nearest the observer,
and K is furthest always. The points C, P appear to h& inside
the solid, and to be in the straight line joining E and N.

Now let the central and the right hand figure be
brought into view in the stereoscope, and it will be ob-
served that the whole aspect of the figure has altered.
This time P is at the front of the figure and C is at the
back, while the points H and K which were previously
the nearest and furthest points appear to be inside the
figure in the straight line joining Q and B.

As the same central figure is used in both cases, the traces
of the two stereoscopic solids on the plane of the paper
are, to all intents and purposes, the same. If, as assumed
they both represent ditt'erent aspects of the same figure
the distances of the different points from the plane of the
paper in the first place must be entirely independent of
the distances from the plane of the paper in the second
case. These distances therefore correspond to different dimen-
sions of space.

In fact, if the first stereoscopic view represents the
projection of a four-dimensional " eight-cell " in a solid

four-dimensional space, corresponding to the five regular
solids enumerated in our text books of elementary solid
geometry, is given by Mr. S. L. Van Oss in the Trans-
actions of the Amsterdam Academy for 1899. The
largest number of faces a regular solid can have is 20,
the figure being known as an icosahedron, but in four-
dimension space, the maximum number of boundaries is
600, and the projections of the "600 cell" shown in Mr.
Van Oss's diagrams are very beautiful and symmetrical.
An interesting variation of the experiments described
in this paper may be made by cutting out the two
extreme figures and placing them simultaneously in the
stereoscope, then inverting one of them and again placing
in the stereoscope. In this manner two other aspects of
the eight-cell w^ill be seen. The scale of stereoscopic
relief will, howe\er, be different to what it was in the
previous observations, but this will not much matter.

N-rays and Smell.

Thh controversv concerning the objective reality of the
N-rays suggests "that to the proverb concerning the difficulties
of accounting for taste, we shall have to add other maxims
about the difficulties of accounting for sight and smell. On
the oue hand. M. Blondlot, Professor Charpentier, and M.
Edouard Meyer continue in their respective spheres of investi-
gation to add new facts each week— by means of papers read
before the Academie des Sciences — to the common knowledge
of the N-rays. On the other hand, Professor J. G. McKendrick
and Walter Colquhoun, as well as other observers in Great

May, 1904.]

KNOWLEDGE & SCIEXTIEIC NEWS.

Britain, have failed to find any trace of the rays as ol)jecti\ c
realities ; Professor C. C. Shcnolc has criticised, in a way which
demands an answer, M. Blondlot's experimental methods and
his alleged measurement of the N -ray's wave length ; and Herr
O. Lummer has suggested, in a paper read before the German
Physical Society, that the observed phenomena are due to pro-
cesses in the retina of the eye (•• the contest between the rods
and cones of the retina "). Meanwhile, the French observers
go on undismayed by the stain of criticism and objection, and
in Cosmos (April 2) Professor A. Charpentier gives the result
of his observations on the connection between X-rays and the
sense of smell. The N-rays, he observes, exercise a very dis-
tinct action on the olfactory sense. It can be shown if the
nose is approached during the action of smelling by a body
capable of producing N-rays, such as a piece of tempered steel
or the closed fist, that the sensation of smell is increased. The
experiment must be made with all necessary precautions, in
still air, very slowly, with gentle and regular breathing, the
odorous substance being maintained at a fixed distance nearly
approaching to the extreme limit at which the olfactory organs
can perceive it. The source of N-rays can either stimulate
the sense of smell when the limit of perception is almost
reached, or increase its intensity where it is already in exist-
ence. In both cases, the action is perceptible. It takes place
when the source of the rays is approached to the root of " the
nose or the base of the nostrils." If the mass of muscles in
the thumb are placed against the nose, the slightest contrac-
tion of these muscles produces the effect already mentioned.
Essence of cassia was the odorous substance usually made use
of by Professor Charpentier, but the same results have been
obtained by him from very different scents — essence of
lavender, thyme, cloves, mint, camphor, ether, iodoforme,
ammonia, and acetic acid among them. The N-ray action
penetrates thin sheets of aluminium, and it is useful in order
to eUminate the currents of air produced, in spite of all pre-
cautions, by displacing the source of the rays, to place a large
sheet of this metal against the outside of the nose, and to con-
duct the experiment on the other side of it.

N-rays can, moreover, influence the olfactory sense when
thev are made to act at certain points on nerve centres if, for
instance, the substance, which is the source of the N-rays, is
placed near the middle of the forehead immediately above the
place where the eyebrows meet. The effect is especially
striking when the source of the rays is placed on the summit
of the cranium a little in front of the place of union of the
frontal and the two parietal bones.

This effect of N-rays is not confined exclusively to the
organs of perception. The scent is increased to some extent
when the radiating source is put near the flask containing the
odorous substance at too great a distance from the nose to
influence it directly. Professor Charpentier continues: "In
the same way I have observed that the substances thus
mentioned distinctly emit N-rays which traverse cork, and alu-
minium, but are stopped to a great extent by lead, and can
give rise, like the other sources, to secondary radiations. As
for the action of N-rays on the other senses, I have found, to
begin with, a very distinct effect on the sense of taste. If a
trace of some highly flavoured substance is put on the end of
the tongue such as camphor, aloes, salt, or sugar, keeping the
mouth open, the breath held, and the palate raised so as to
avoid all olfactory influence, the approach of a radiating
source, such as a ball of tempered steel, reinforces or creates
the sense of taste. The same thing happens when salt or
other substance is diffused in the mouth instead of keeping it
on the end of the tongue. .Are there points of the brain on
which N-rays can act by determining an increase of the sense
of taste? After experiments with different parts of the
cranium, I h.ave only found a certain degree of action in one
parietal zone, next to that which acts on vision, perhaps a little
behind it. The study of hearing is more difficult, because of
the precautions to be taken in order to prevent the currents
of air displaced by breaking the source of radi.ition interfering
with the conditions of arrival of the sound. It can be done,
however, by making use of secondary radiations. Now, in
taking as the .source of sound a watch held at the extreme
distance at which the sense of hearing c-an perceive it, I have
only clearly proved some increase of sound when the terminal
plate was placed right above the ear at 7 to S centimetres from
the orifice of the ear, which appears to confirm the idea of an
excitation affecting the central centres of hearing.

The Single-Phase Motor
in Germany.

Thi-: single-phase tr.ictiou motor which has been designed
by the Union IClectric Company, Berlin, according to Wmter
and luchberg's data, and which is being tried on the Johan-
nisthal-Spindlersfeld suburban line, near Berlin, is thus de-
scribed bv our Berlin correspondent :

The motor includes a stator similar to those of ordinary
induction motors, containing a single-phase coil arranged in
notches, and a collector armature which is designed like the
armature of a direct current motor, and to which two sets of
brushes with axes perpendicular to one another are fixed.
The first set, the axis of which coincides witli the axis of the
stator coil, is short-circuited. It carries tlie working cmrents
proper. These are induced by the field 0 in the direction of
the axis of the stator coil of a series transformer that is niserted
in the main-current circuit, and carries only magnetising cur-
rents. The magnetising currents produce a transversal field
F perpendicular to the field </>. by which, in conjunction with
the stator current, the efficient torque is produced. The
presence of two separated fields enables the motor to work

5ingle"Phase Motor in use on the Spindlersfeld Railway.

without sparking. The electro-motive force generated in a
winding that is short-circuited by a brush through the induc-
tion of the field F is perfectly compensated as the speed of
revolution increases, by the electro-motive force due to the
rotation in the second field ip. That would be impossible in the
case of monophase series motors, where, in the winding short-
circuited through a brush, an electro-motive force independent
of the number of turns, and incapable of being compensated,
is induced.

Moreover, by the rotation of the armature, an electro-motive
force is induced in the exciting circuit of the armature which
is able not only to compensate perfectly the undesired electro-
motive force of self-induction of the circuit, but at the same
time the electro-motive force correspondmg to the primary
and secondary leakage. With an increasing number of revolu-
tions the power factor will thus approach the value cos <(> = i,
this value being maintained constant within wide limits on
account of the unique regulation. Without any prejudice to
motor efficiency, the air gap may therefore be made as great
as in the case of direct current motors, and open stator
notches may be used instead of closed notches. The ratio of
the exciting' transformer is regulated by the insertion or dis-
connection of windings. In the case of the series transformer
being adjusted for a given ratio the motor will behave in a
way (juite similar to direct current series motors, lioth the
current intensity and the torque having the maximum value at
rest and decreasing for incre.ising angular speeds. In the
case of the ratio of the series transformer being diminished,
the characteristic curve of the motor is displaced so as to

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

have the same torque as previously observed with a given
numl^er of revolutions Mj appear only at a number of revolu-
tions Mi (superior to Mj). The same number of revolutions
will now correspond with a hij^her torque than before, the
torque at rest being evidently also higher.

The motor is started by altering the ratio of the regulating
transformer. The current of the c.xcitor brushes being thus
interrupted at rest, the primary coil of the series transformer
will act as a reaction coil, and the whole motor will be traversed
only by a very small current. It will thus be unnecessary to
open the primary coil of the motor when stopping. It is suffi-
cient to open the exciting circuit (low tension coil) because the
motor works only in the case of the exciting circuit being
closed.

The motors of the Spindlcrsfeld cars have an output of
about 100 H.P. hours: they have four poles and a monolateral
air gap of 3 mm. The total weight of a motor, including the
small toothed wlieel, is 2140 kg., the weight of the exciting
current transformers common to both motors being iioo kg.
As regards the arrangement of the connections, the direct
current multiple unit system of the Union Elektricitats GescUs-
chaft has been used and slightly modified. Two cars are being
used in connection with the johannisthal-Spindlersfeld trial
runs, in addition to three trailers, each 16 tons in weight. The
experimental trains arc run on the same track as used for the
regulation steam trains, and are inserted between the steam
trains according to a fixed time table. The cars are designed
for a maximum speed of 40 km. per hour, though speeds as
high as 60 km. are sometimes reached. The motors have
given full satisfaction even in the case of the highest strains,
the whole train, including two motors and three trailers
(155 tons), being often arranged and driven by the two motors
only. The perfect independence with respect to the line ten-
sion has proved a special advantage as compared with the
rotary current system, two-thirds of the line tension having
been sufficient to maintain the regular service, while starting
and running at a speed of about 30 km. was possible with
40 per cent, of the motor tension.

A. G.

Recent Explosions.

By Charles Davison, Sc.D., F.G.S.

Interesting evidence with regard to the propagation of sound
by the atmosphere is afforded by the firing of heavy guns
during reviews and sham fights, and by explosions in manu-
factories of dynamite and nitroglycerine. Examples of the
former class have been given in two recent papers. ■ During
the great naval review at Spithead on June 26, 1897, held in
honour of the late Queen's Diamond Jubilee, the sound of the
first salute was heard as far as Weston, near Hath, at a distance
of 71 miles. Again, on July 18, 1900, when the I'rench Presi-
dent visited Cherbourg, a sham fight took place between
two portions of the French fleet, giving rise to disturbances
that were mistaken for earthquakes at many points along
our southern coasts. The reports were heard from
Dawlish and Exmouth on the west, to Brighton and
Henfield on the east, the distance from Cherbourg to the
latter place being 107 miles. Lastly, during the funeral
procession of our late Queen, on February i, kjot, the
minute-guns were heard as far as Alderton, near Wood-
bridge, in Suftblk, which is 139 miles from Spithead,

In the present paper, I propose to describe similar
evidence derived from two recent explosions, the first at
Hayle, on January 5, of the present year, the second at
Avigliana, near Turin, on January 16, 1900!.

♦ "The distance to which the firing of heavy guns is heard ; "
Nature, vol. Ixii., 1900. pp. 377-379: "On tlie audibility of the
minute-guns fired at Spithead, on February i: " Knowledge,
vol. xxiv., i9oi,pp- 104-105.

f For the account of the H,-xylu exiilosioii, I have relied on the
reports which appeared in the M'estern Morning AVa-s (Plymouth),
and on replies to ,a letter whicii the ICditor of that paper kindly
inserted. Dr. M. Baratta has puljlislicd an interesting report on
" Lo scoppio del dinamiti-ficio cH .\vigliana c la geo liscia (16
gennaio, 1900) : " Turin, 1900.

The HaLyle Explosion of January 5, 1904.

The works of the National Explosives Company at Hayle
are situated on waste land, known as Upton Towans, about two
miles north-east of Hayle and between three and four miles
east of St. Ives. To reduce all risks to a minimmn. the
separate buildings are isolated as much as possible ; and, to
lessen the loss of life, in case an explosion should occur, the
number of men employed in any building is always small. It
was no doubt owing to the observance of these precautions
that the loss of life during the recent disaster was compara-
tively slight.

At the time of the explosion (10.55 a.m.), nitro-glycerine was
flowing down a gutter from the precipitating house to the
filtering house, the latter lying about 400 yards north-west of
the former. Only one man was working in the precipitating
house and three men in the filtering house. It appears tliat
the precipitating house was the first to explode, and that,
owing to the temporary connection by means of the gutter,
the filtering house followed immediately. This conclusion
rests on the evidence of an eye-witness ; on the fact that
persons to the south-east of the houses heard two reports
separated by from li to 2 sees., while those in the opposite
direction heard only one; and on the cDndition of the gutter,
which was not covered by the debris from the precipitating
house. Both houses were, of course, destroyed, and their
occupants killed instantaneously. As to the cause of the ex-
plosion, it can only be surmised — but the surmise is a probable
one — that it was due to the fall of some heavy weight, cither
of one of the lead cups used to catch the droppings from the
taps, or, more prol^ably, of the lid of one of the tanks. In any
case, the disaster must have been purely accidental in its
origin.

The results of the explosion were visible for several miles
around the works, chiefly in the breakage of glass. At Hayle,
many windows were blown out. At St. Ives, the damage was
estimated at not less than £200, but its distribution was par-
tial, some houses suffering and others close at hand escaping ;
and it is worthy of notice, though the peculiarity has been
recorded before, that the windows, especially in houses facing
the works, were blown, not inwards, but outwards. Similar
damage also occurred at St. Erth (3* miles from the works), at
Leedstown (4 miles), and, though to a mtich less extent, at
Penzance (distant 9 miles).

A suiall oscillation of the ground was also noticed in the
surrounding district. At St. Ives, according to my informant
quoted above, the vibrations could not be distinguished from
those produced by an earthquake. At much greater distances
windows were shaken ; but this must have been caused by air-
waves. Observations of this kind were made at several
places in Devon, at Ivybridge and Modbury (68 miles), near
Torrington (74 miles), at Paignton (83 miles), Torquay
(85 miles), and Teignmouth (88 miles).

The distribution of the places where the reports were dis-
tinctly heard is shown in the sketch-map in fig. i. To the

Scalt al Milts

HaTtlanS

Fulford

Fig. 1.

May, 1904."'

KNOWLEDGE & SCIENTIFIC NEWS.

north-oast, the explosion was audible around Holsworthy
(62 miles from the works), Hartland (fiS niilosK and Torring-
ton: and to the east at many places in South ncvon as far as
Exeter, which is not less than ()o miles from the centio of dis-
turbance. Thus the sound must have beon heard over nearly
the whole of Cornwall, and the ,i,'reater part of Devon, or over
a total land-.area of about 3000 sijuaro miles.

In the case of the minute-guns fired .at Spithead on Feb-
ruary I, icjoi, a curious anomaly was observed. In the imme-
diate neighbourhood of Spithead, the sound-waves were
almost or quite inaudible, and it was only at a distance of
50 miles or more up to about So miles that .they attracted
general attention. Owing to contrary winds, the somul-waves
were refracted over the heads of observers near at hand, and
were brought down again by favourable winds to the earth's
surface at greater distances. The Hayle explosion affords
another instance of this remarkable eft'ect. .\t Camborne,
which is only 4 miles east of the works at Hayle, no one,
according to one of my informants, seems to liave heard the
reports, and, he adds, the wind at the time was blowing in the
contrarv direction.

The Aviglia-na. Explosion of January
16. 1900.

The little town of .Avigliana hes in the valley of the Dora
Kiparia, a tributary of the Po, about 14 miles west of Turin.
As at Hayle, the various buildings which constitute the dyna-
mite factory are isolated from one another, the whole being
comprised within an area of about 50 acres.

The first and greatest explosion occurred in the building in
which the nitro-glycerine was prepared, and which, at the
time, was estimated to contain about 400 kilogrammes of this
material. This was followed by the explosion of nearlv 12,000
kilogrammes of dynamite and fulminating cotton contained in
magazines which were probably ignited by the fall of burn-
ing materials from the first building destroyed.

Scale oi TVTiles

O 10 7J) io UO io

A-t^UTtO^

Pai

I
I

a. '

\
I

\
o \

1 \

1 ^

Fig. 2.

The curves in the accompanjnng sketch-map (fig. 21 give
some idea of the distribution of the damage and other effects
due to the explosion. The area of maximum destruction was
practically co-extensive with the factory itself. At Avigliana.
which is about half a mile distant, all the window-panes were

broken, and in several of the oldiu- houses cracks were made
in the walls .-ind arches. Similar, (hough somewhat slighter,
damage occurred at several neighbouring places, all inclndid
within the curve marked n, which cmilains an area of .iliout
So stjuare miles. Outside this central area lies a /one bounded
by the curve h, containing about iSo s(|uare miles and reach-
ing to the western suburb of Turin, within which manv, but
not nearly all, windows were broken. In the next zone, lying
between the curves b and r, the air wave was strong enough
to make doors and windows rattle. It will be noticed that
the dynamite factory is at some distance from the centres of
all three curves, the last of which (i ), indeed, extends 40 miles
east of Avigliana and only eight mil(;s to the west.

Beyond the latter curve the only effect observed was a
rumbling sound like that of distant thunder or a cart of wood
being unloaded. This was heard at i-onsiderablc distances in
some directions, but the peculiar form of the curve (/ which
bounds it is in part, no doubt, owing to a defective series of
observations. Towards the south-east it reaches as far as
S.avona (75 miles), towards the east to Pavia (87 miles), and
towards the north-east as far as Lugano (qij miles). On (lie
other hand, towards the west the sound was inaudible at Susa
and Fcnestrelle. 1> )lh of which are only 17 miles from Avig-
liana.

Dr. Mario Haratta, who has stuilii'tl this ex])losion, considers
that the restriction of the curves towards the west is in great
part due to tlie form of the land-surface. Without under-
rating the effects of the wind, the direction of which at the
time of the explosion is unknown, he points out that tlie path
of the waves would be obstructed by the mountain ranges
lying to the west and south-west, wliile the open ground along
the valleys of the Dora and Po would allow free passage to the
sound-waves in other directions. Comparing the curves of
lig. 2 with a contour-map of the district, he finds that the
rc]-)ort of the explosion was never he.ard in places situated at
an altitude of more than 1000 metres.

ASTRONOMICAL.

A new form of Dipleidoscope.

In a brief note communicated to the Royal Dublin .Society,
.Sir Howard Cirubb describes a simple little instrument for
readily determining the true time by observation of the sun.
The instrument in (juestion, the dipleidoscope, was originally
devised more than sixty years ago by E. J. Dent. It consisted
of a right-angled prism so placed that the sun, when near the
meridian, could be viewed in it obliquely, when two images
were seen, the one due to rcllection from the first surface, the
other to double reflection from the- two inner surfaces. The
two images would therefore appear to move in different direc-
tions, and when the prism was properly set would overlap
when the sun was on the meridian. The instrument, however,
as originally devised, was open to some serious ol^jections.
The one image of the sun was faint, the other excessively
brilliant, and neither being magnified, the observation was
only a rough one. By covering one-h.alf of the prism with 'a
film of sulphide of lead, and by adding a lens of 20 feet focus,
Sir Howard Grnbb has been al)le to make the two images of
equal brightness, and sufficiently large for an imskilled
observer to determine tlie lime to the nearest second.

# « *

RegistraLtion of Sta.r Transits by
Photography.

Sir Howard (irubl) has made an exceedingly in,i<enious yet
simple suggestion for getting over the difficulty which has been
experienced in employing photography to register star

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

transits. The photographic plate must be made to travel
if the registration is to be extended to the fainter stars, and
the rate of motion should vary with tlie declination of the
star. The suggested solution would place the object glass of
the transit instrument in its horizontal axis, and the photo-
graphic plate would travel on the arc of a circle, the centre of
which coincided with the centre of the object-glass. This arc
would be carried by a polar axis, the prolongation of which
would pass through the centre of the object-glass. If the
polar axis were driven uniformly by clock work, as in the
ordinary equatorial, the plate would always move at the
pniper rate for the declination of the star to which the tele-
scope was pointed, and would .ilways lie in the focus of the
transit telescope.

* ♦ ♦

Burnham's Mea.sure of Double Stars.

.•\mongst the decennial publications of the University of
Chicago is a memoir by Frnfessor S. W. Biirnham on his
" Measures of Double Stars," made with the 40-inch refractor
of the Verkes Observatory in igoo and igoi. The memoiris
one of very great importance, because the work undertaken
by Mr, Burnham was the re-observation of stars which had
been neglected, in most cases entirely, for some seventv or
eighty years. The majority therefore are wide, or verv wide,
pairs, and could have been successfully dealt with by the
instruments in the possession of not a few amateurs, so that
the devotion to them of the largest telescope and the most
gifted ob.server in the world is something to be regretted. But
since there was none other fulfilling the dutv, Mr. Burnham
has performed a great public service in discharging it, and
incidentally has succeeded in discovering some eighteen new
pairs, some of which are evidently of \'erv high interest.

* « *

Mr. Lowell on Changes in the Ma.rtian
Canals.

Three papers reccntlj' published by Mr. Lowell carry his
researches on Mars a distinct stage fmiher. Two of these are
issued as Bulletins Nos. 7 and 8 of the Lowell Observatory,
and deal with the variation in colour of the Mare Erythasum
and the alternating appearances of the canals Thoth and
.\menthes. The third paper, entitled "The Cartouches of
Mars," was communicated to the .American Philosophical
Society. In this last Mr. Lowell discusses some 375 drawings
of the planet, made during the opposition of 1903 from
January 21 till July 26. Eighty-fivo canals were observed, and
each canal on the average might have been seen one hundred
times. For each canal a curve or " cartouche " was drawn
out to exhibit the percent.ige of times that it was observed
wlien, from the presentation of the planet, it should have been
visible, for different intervals after the sunmier solstice. The
mean cartouches for the different zones are far from being
convincing, and represent the smoothing out of many discord-
ances. It may be granted, however, that there is some slight
resulting evidence that on the whole the date of greatest dis-
tinctness for a canal falls later in the summer of Mars in pro-
portion to its distance from the pole. This darkening of the
canals proceeds towards the equator at a speed of 53 miles a
day. Mr. Lowell considers this as motion in the face of
gravity, the equatorial radius of Mars being eleven miles
greater th.in the polar, and as demonstrating that the canals
are waterways and that the water is raised to this height by
artificial means. The Thoth and the .■\menthes offer a case,
according to Mr. Lowell, of alternative canals, the one canal
being visible in one season and the other in another. Mr.
Lowell also finds that the Mare Erytha;um shows a distinct
bl';e-green tint at the time when he infers there is most moisture
in the region and a chocolate-brown when there is least, a
change he ascribes to the decav of vegetation.

* * *

Sunspots and Terrestrial Magnetism.

Professor Ricco contributes ;in inijiortant memoir on this
subject to the Societa degli S])ettroscopi It.aliani. He refers
at length to Mr. Maunder's recent paper on the nineteen great
m.agnetic storms of the last thirty years, and fully adopts his
conclusion that there is a real connection between sun-spots
and such storms. Mr. Maunder found that the storms began on

the average 26 hmii-. ilter the transit of a great spot across
the central meridian of the sun. Professor Ricc6 finds that
the maximum violence falls about 455 hours after the transit.
As the mean duration of a storm is a hours, the two deter-
minations are almost precisely in accord. Referring to a num-
ber of suggestions which have been made to explain the sun's
influence on terrestrial magnetism. Professor Ricco appears to
favour that of Arrhenius, who suggests ions, driven from the
solar surface by reason of the pressure of radiation : their
velocity being nearly tliat indicated by the interval mentioned
above.

ZOOLOGICAL.

Ea.rly Opening of the Bright Eye.

In a note to certain observations on the gestation of the
badger, published in the March number of the Zoolof;ist, Mr.
A. Heneage Cocks records the following \ery remarkable cir-
cumstance : " I have never seen the fact noticed," he writes,
■• that the right eye of young mammals opens before the lelt.
I do not remember an exception among wild animals, nor even
among domestic animals, though it is very likely some occur
in the latter class. From the time the lids of the right eye
begin to part to the time the left eye is fully opened takes
generally from 36 to 40 hours." The fact is as new to us as it
is to Mr. Cocks, and requires an explanation. The suggestion
naturally occurs that the phenomenon is coimected with
"right-handedness" in the human species; but before such an
explanation can be accepted, we want to know whether car-
nivorous and rodent mammals, and the membersof such other
groups as have the young blind at birth, display a similar
preference for using the right limb. The horse, it is well
known, di.splays a decided tendency to " lead with the left
foot ; " but in this species, in common with other ungulates,
the young are born with their eyes wide open. And what
holds good in this respect with domesticated horses may not
obtain among carnivores and rodents.

The "Pearl Organs " of Fishes.

Tiie males of certain species of North American fishes
develop during the breeding season what are known as " pearl-
organs." These are hard spine-like thickenings of the epi-
dermis, sometimes forming rows on the sides of the tail and
on the anal fin. Their use long remained unknown. Mr. J,
Reigh ud, of Michigan Universit}', finds, however, that they
are employed by the males of some species for fighting and in
building their nests, while in all the species they are used for
holding the spawning female.

Whale Collisions.

Two instances of the sudden destruction of whales by colli-
sion have recently been recorded in the daily papers. In the
one instance the look-out on a liner noticed a large whale dis-
porting himself OT the surface of the water immediately ahead,
but, thinking that the monster would get out of the way in
time, the vessel was allowed to pursue her course. Instead,
however, of moving, the whale .remained where he was, and
was caught " amidships " by the bows of the steamer, which
cut him conipletelv in two. For two or three miles, it is said,
the vessel ploughed her way through water crimsoned with
the leviathan's blood. The second case is recorded in a tele-
gram sent from Vladivostok on March 30. " A violent ex-
plosion," runs the message, " recently occurred at sea in
Possiet Bay, the cause of which could not be ascertained.
Two days later the bodj' of an enormous whale was washed
into the bay by the tide, the creature having evidently collided
with and exploded a mine."

Monkeys aLnd Altitude.

A recent issue of the ^//i of the Roval Academy of Rome
contains an account of the effects produced on baboons and
monkeys bv conveying them to a high elevation on Monte
Rosa. The ill effects seem more pronounced than in the case

May, 1904.]

KiNOWLEDGE & SCIENTIFIC NEWS.

of human beings. The action of the low haroiuetiic
pressure appears very similar to that of uarootics, prodiuing
at first unusual activity and excitement, follovved l)y sleepiness,
iusensibility, aiid, finally, death.

The Brairv of Man a-nd Apes.

For many years Professor G. lUliot Smitli, of the Msjyptian
Government School of Medicine, has been devotinj; his atten-
tion to the study of the brain in man and other mammals.
Recently, in the Anntoinischc'r Aiizcirffr Ijcnay, he has pub-
lished a preliminary account of what appears to be an exceed-
ingly important discovery. The human brain, as known by
European specimens, has been supposed to difter from that of
apes and monkeys by the absence of the so called simian fold
(" Aftenspalte ■') on the posterior portion of the main hemi-
spheres. On studying a large series of Itgyptian ,ind Sudani
brains. Professor Smith finds, however, that this simian fold,
or sulcus, can be distinctly recognised.

" It is easy," he writes, •' to select examples from the series
of Egyptian and Sudanese brains in my possession in which
the pattern formed by the occipital sulci on the lateral surface
of the hemisphere in individual anthropoid apes is so exactly
reproduced that the identity of every snUus is placed beyond
reasonable doubt. . . . .\nd if we take individual examples
of gorilla brains it becomes still easier to match the occipital
pattern of each of them to numerous human brains. . .
It is easy to appreciate the difficulties which have beset inves-
tigators of European types of brain, and to understand the
reasons for the common belief in the .absence of the supposed
distinctly simian sulci in the lateral aspect of the occipital
region of the human brain."

Thus disappears one more of the supposed structural dis-
tmctions between man and his nearest relatives.

Zebra Ta-ming at the Zoo.

AUintere.sted in the progress of the Zoological Society's .Mena-
gerie in the Regent's Park, and the attempts now being made
to render it more attractive to the general public, will have
heard with unfeigned regret of the sudden death of the Grevy
zebra stallion shortly after the first trial at breaking it for the
saddle. With regard to the experiments made for timing all
the specim<?ns of the zebra at present in the collection, it
appears that the smallest and quietest of the three mares was
some time ago broken in with very little trouble. ( )n March 15,
'•Jess," a larg<'r and somewhat less docile mare, was taken in
hand, with most successful results; and the same afternoon
the third mare was handled with equal success. .All three
mares have since been going about quietly in harness, although
it was deemed advisable not to take "Jess," as being by far
the most powerful, beyond the limits of her paddock. On the
following day. March 16, the Grevy stallion was taken in hand,
although it was never intended that he .shoidd be employed
for riding purposes. Although some temper was displayed by
the stallion, he was eventually broken w ith complete success.
During the next two days he seemed perfectly well, bat he
showed signs of being out of condition on Saturday, and, after
refusing to get up on the morning of the Sunday, he died that
night.

The post-mortem examination was made on Wednesday,
March 23, by Dr. Salaman, Director of the Pathological Insti-
tute at the London Hospital. The immediate cause of death
was heart-failure, but Dr. Salaman was unable to find evidence
of the actual cause of failure ; the complete absence of signs
of injury or disease being similar to the case of a Grant's
zebra examined by hiiri at the beginning of March, which
had died in the Gardens without having undergone any
training or breaking-in.

Although it is obviously impossible to be certain that the
death of the Grevy was unconnected with the breaking-in, it
is satisfactory to know that there was no sign of injury to any
of the internal organs. The bones were, however, unusually
brittle, and the stallion was much older than had been sup-
posed. Our readers will be glad to hear that this untoward
event is not to be allowed to interfere with the progress of
zebra-training.

The Collections of the "'Discovery."

According to tln' daily papers, the re>-ults of llie expedition
of the " Discovery " to the .\ntarctic do not appear lo havi'
■added anything very striking to our biological knowledge.
So far as zoology is concerned, the most important item is,
perhaps, the discovery of a " primitive type " of insect. \'alu-
.able information with regard to the bird-life is, however, said
to have been obt.dned. Most important of .all a]ipe,irs to be
the discovery of a number of fossil-plant remains, which are
said to confirm the theory of a former land-connection, by
wav of " -Vntarctica," of the southern continents and isl.uids.

BOTANICAL.

An Abnornnal Fern.

.[spiiliuiii iiiioiiuihiin is a fern fovmd growing at high eleva-
tions in Ceylon. It closely resembles the British A. iiaiU'tiluiii,
of which it may be merely a form, and very remarkable on
account of the sori being developed on the upper instead of
the under side of the fronds, the usual position for them. The
plant is now in cultivation in this country, its large liandsome
fronds rendering it of consideral)le horticultural merit. The
species was first described by Sir William Hooker nearly half-
a-century ago under tlie name of i'dlijpotliuni annnuilum, and
he regarded it ;is an abnormal form of P. veslitum. He found
that the indusium was entirely absent even in the youngest
stages of the fructification, while in P. vestituin it was very
earlv deciduous. Other ferns are known to occasionally
develop a few sori on the upper side of the frond, as in Dcpana
Moiiii-i, wh('re they are confined chiefly to the margin, ;uid
sometimes in AspU-niiiiii friihuinanes. Sir Willi.iin Hooker
refers to a specimen of this species, collected in Italy, in
which, in addition to the numerous sori on the under side of
the frond, there was one pinna "bearing a solitary sorus on
the disc of the upper side." In the specimen from which Aspi-
dinni anotnaliim was first d(^scril)ed a few sori were found on
the under side of two or three pinnules of a frond.

A Primitive Food.

Professor F. W C'oville h.is ju;,! pulilished an interesting
paper on a primitive food of the Klamath Indians, produced
bv a congener of our yellow water-lily (Niiphar lutcuni), and
known under the native name of Wokas. This plant is A'.
pulyscpiilum. called by .American botanists N ipupluca polyscpahi,
and is found in great abundance in the reservation occupied
bv the Klam.ith Indians in the south-western corner of the
plateau of eastern Oregon, at the eastern foot of the Cascade
Mountains. A huge marsh in this reservation, known as the
Klamath M.arsh. contains no less than ten thousand acres of the
Wokas, which fiourish to the exclusion of almost every other
kind of vegetation. The seeds are subjected to various tedi-
ous processes by the natives and ultimately furnish a wholesome
farinaceous food, which is regarded as a great delicacy, and
which Professor Coville thinks might be successfully brought
into commerce as a bn-akfasl food, though he does not con-
sider the cultivation of the plant for commercial purposes to
be feasible, and the supply of the seeds would be dependent
on the wild crops. The order Xympha-^acea; is not impnrtant
economically. The seeds of the Victoria rei^ia are eaten by
the natives of Guiana and Pirazil, and the stem of the Sacred
Lotus (Xiliinihiuni ■ipriiiisuin) "is used as food in India and
China, though probably only in times of scarcity."

PHYSICAL.

On a Novel FLadiation Phenomenon.

Mr. J. J. Taidin CHAnoT-- some time ago ascertained whether
selenium in its conductive modification, being sensitive to
light, may give rise to radio-active phenomena. To this effect
he used a selenium cell of the Shelford Hidwell type, the

* Physihal Zcitschr., No. 4, pp. 103-104, 1904.

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

effective mass of which was uniformly distributed on the sur-
face of a platinum wire. After having been in the dark for
many weeks, the platinum selenium surface was covered, at a
red illumination, with a sheet of silver bromide jelly to which
a sensibiliser absorbing the yellow and green rays was added,
an aluminium strip bent at right angles being interposed.
After the whole system had been kept in the dark for another
48 hours, the same experiment was repeated, using a fresh
silver bromide jelly sheet, while a current of about no
microamperes traversed the selenium. Now the following
results were observed on the developed jelly sheet : —

In the first case, some bright spots corresponding apparently
to the outline of the aluminium angle were noted on a dark
background, whereas, in the second case, a dark silhouette
of the whole of the angle without any details resulted on a
bright background, some brighter narrow transversal bands
being visible at the same time. These bands were produced
more efficiently in the case of repeated expositions, thus
allowing of ascertaining that they are due either to the parallel
platinum wires or to the selenium interposed between each
two of these, or finally to the points of contact between the
platinum and selenium, where the Peltier effect must give rise
to an evolution of heat either positive or negative, on the
passage of the current.

On continuing these experiments. Mr. Chabot noted the fact
that the back of the plate bearing the platinum selenmm wire
was equally capable of affecting the silver bromide jelly, dark
silhouettes on bright background being then obtained. As to
the question whether these results are an evidence of the
existence of some novel radiation, or else an emanation from
the surface of conductors, the author hopes to publish in due
course some further investigations allowing of more definite
conclusions being drawn.

R-adium a-rvd Heat.

In the course of an experimental investigation of the in-
fluence of radium on the rate of cooling of a body placed in a
gaseous medium, Mr. Georgiewsky. in a paper recently read
before the Russian Physico-Chemical Society, arrives at the
following conclusion : —

1. The rate of cooling of heated bodies in the various gases
is not modified under the influence of radium.

2. The rate of cooling of non-electric heated bodies placed
in one of the gases examined (hydrogen, lighting gas, air and
carbonic acidi on being exposed to the action of radium is
augmented in the case of the heated bodies being electrified.
The rate of cooling in this case will augment not only under
the simultaneous influence of the a, S and 7 rays of radium,
but as well under the exclusive action of ;3 and 7 rays,

3. The increase in the rate of cooling of a heated body is
greater as the body is negatively charged.

4. The relations existing between theincreasein the thermic
conductivity and the potential of a charged and heated body
may be represented by means of curves analogous to those by
which Mr. Townsend expresses the connection between a : p
and X : p for the same gases {Pliil. Miif;. 6 ser. V. 5, p. 571).

A. G.

ORNITHOLOGICAL.

By W. P. Pycraft. A.L.S.. F.7.S,, M.R.O.U.,&c.

Breeding Habits of the Common Buzzard

[Buica vulgaris).
Professor J. H. Salter gives an exceedingly interesting
account of his observations on the nesting halrits of the
Common Buzzard in the '• Zoologist " for March. Of the
three young which are almost invariably hatched, he remarks
that, in the hill districts, the oldest bird will commonly kill one
or both of the younger nestUngs ; apparently for the' purpose
of securing their share of the food brought by the parents. In
support of this view he points out that this unnatural behaviour
is not noticeable when the young are reared in the more fertile
valleys where food is plentiful.

He also describes a curious habit which the parents have
of decking the lining of the nest with freshly-plucked leaves
and twigs, especially of birch, and rowan, and bracken.

Birds breeding in Wales furnished the material for this
extremely interesting history.

* ± *

Greenland Falcon in Donegal.

It has just come to light that .in inunature bird of this
species was trapped in Donegal in December last. This
makes the thirty-second record of this species for Ireland,
and the tenth for Donegal.

Nutcracker in Northamptonshire.

A trap set for " vermin "in February last, at Ty well, captured
instead a Nutcracker, whilst one is reported to have been seen
in Devonshire during the same month.

The Emperor Penguin.

A statement has been going the round of the daily papers
to the eftect that one of the results of the newly-returned
Discovery Expedition to the Antarctic has been the capture
of the Emperor Penguin, a bird which had " not previously
been found in these regions." Of course this is a mistake ; but
we are glad to learn that the eggs of this bird have been taken,
for they have not hitherto been, and will therefore form
a welcome addition to the collections of the National Museum
at South Kensington.

All communications intended for this column should be
addressed to : —

\V. P. Pycraft,

Natural History Museum,

South Kensington.

'^i "^i '^^ ^^i ""^i

REVIEWS OF BOOKS.

First Causes.

The Old Riddle and the Newest Answer. By John Gerard
S.J., F.L.S. (Longmans.) The old riddle which the Rev
John Gerard tries, not to answer, but to state, is that which
asks whether it is possible to explain the universe without
admitting the existence of a Creator. The answer he gives is
that no theory which has yet been formed can relieve us from
the necessity of imagining a First Cause ; there must have
been a God. a Divine Intelligence greater than any intelligence
which man can attain. Mr. Gerard's conclusion is well stated
in a quotation from the late Professor Baden-Powell — "That
which requires thought and reason to understand must be it-
self thought and reason. That which mind alone can investi-
gate or express must be itself mind. And if the highest concep-
tion attained be but partial, then the mind and reason studied is
greater than the mind and reason of the student. If the more
it be studied the more vast and complex is the necessary con-
nection in reason disclosed, then the more e\"ident is the va.st
extent and compass of the intelligence thus partially mani-
fested . . . ." But though we have no quarrel with the
conclusion that Mr. Gerard reaches, and though we may admit
that it has been expressed in varying forms by the greatest of
scientific men — by Kelvin, by Lamarck, by Sylvester, even by
Huxle}- — there is a distinct objection to the means he has taken
to reach it. He opposes the theory of Evolution by the doc-
trine of Design. A very large part of his volume is occupied
by an attack on Darwinism, which we cannot even admit to be
a fair attack. Darwin's theory is not infallible: its too zealous
advocates ha\e sometimes stretched it farther that it can legiti-
mately be held to go. In any case it is but a working model,
and, like the atomic theory, or the theor}^ of the ether, or the
chemical theory of ionic dissociation, or the new theories
based on radio-activity, it is to be regarded not as a complete
explanation, but as a hypothesis which enables us to account
for many of the facts. Even if it were completely true, it
would not prejudice the belief in a Creator; if it were proved
entirely mistaken it would not strengthen that belief. Why

May, 1904.]

KNOWLEDGE & SCIENTIFIC NFAVS.

then assail it as a factor in the argument ? If, on the other hand,
the Darwinian theorj- be assailed on other than dialectic or
theological grounds, then the tirst necessity is to be scrupu-
lously fair, meticulously exact. W'c have not sp.ace to consider
critic.-iUy all the quotations which Mr. Gerard brings forward
as evidence against it : but we may briefly refer to one part of
his case, which is contained in the chapters on the geological
record. He (piotes with approval the attacks which Mr.
Carruthcrs made in 1S76 .as President of the Geologists' Asso-
ciation, and later in book form (iSySl, on the incompleteness of
the bot.anieal fossil record, and its failure to show any connect-
ing link between the greater divisions of plants. But Mr.
Gerard entirely ignores the work which has been done since
iSgS by Professor A. O. Seward, Dr. 1). H. Scott, and Pro-
fessor F. W. OUver in fossil botany, and the opinions expressed
by them. To quote but a single instance: Dr. D. H. Scott
and Professor F. W. Oliver have within the last twelve months
shown reason for connecting the Ferns with the Cycads; and
have exhibited in Lyginodendron a seed-bearing fern. Not,
however, to go into too great detail, we may quote from Pro-
fessor Seward's British Association address an observation
made by Darwin himself on the imperfection of the geologic
record, " The crust of the earth, with its embedded remains.
must not be looked at as a well-filled nniseum. but as a poor
collection made at hazard and at rare intervals." And the
transitions of form and species are not incompatible with evo-
lutionary theory.

A Chemical Conceptiun of the litlier. 15y I'rofessor I).
Mendelceff. (London : I^ongmaus, Green, and Co.) The
discovery of the radio-active properties of some of the metals.
and the probability which Lord Kelvin remarked, that most
substances are radio-active to a greater or less extent, has
been one of the corroborative facts to sustain the electro-
atomic theory of matter. That theory has been hesitatingly
received by many chemists, who have not hesitated to dispute
the objeeti\e reality of atoms — regarding them merely as
vehicles for expressing relations between the elements — and
who have seen in the extension of the theory so as to take in
"atoms of electricity" or "electrons," or "twists in the
ether," an unprovable hypothesis which they do not need to
explain chemical inter-action. The attack on the physicists'
conception of the atom of matter as an imperceptibly small
system of forces in which electrons revolve at enormous speeds
and possibly in concentric rings (not unlike a solar s3'stem in
miniature, or the rings of moons about the pl.met Saturn) has
not hitherto been very well directed. It has in at least one
instance put forward an untenable explanation of some of the
facts of radiation ; and while ignoring the fact that the
•■ electron " theory does explain the radiation of radium and
thorium very well, has offered no alternative theory. Pro-
fessor MendeleefTs theory of the ether removes, however, the
latter reproach, and offers a supposition which, though await-
ing the test of mathematical examination on the part of the
physicists, is an extremely interesting one. He boldly sweeps
away the anomalies of believing the ether to be an all-
per\'ading substance — rigid as steel, yet interpenetrating all
matter; frictionless, but without weight — by imagining it to be
a gas that has weight and substance, though it is of such
extreme tenuity that it is capable of interpenetrating .ill
other substances and incapable of offering a measurable
resistance to their passage among its molecules. Its in-
susceptibility to chemical combination is to be regarded as
similar to a similar inertia on the part of helium or argon, or
the gas emanating from radium ; its imponderabihty is not
real, but due merely from the absence of an)' known means of
weighing it. Professor Mendelceff calculates that this theory
w'ould fulfil the requirements mathematically demanded from
it if the ether, the lightest element, and its particles and atoms
had an atomic weight nearly one-millionth that of hydrogen,
and travelled with a velocity of about 2250 kilometres a
second. We need not follow Professor Mendeleeff's theory
in all its details, but it will not be uninteresting to summarise
the way in which it responds to the demands put on it to
explain radio-activity. Although the ether, or, as he calls it,
the lightest of gases, x, has no power to form stable chemical
compounds, it would not be deprived of the faculty of dis-
solving in, or accumulating about, large centres of attraction
— like the sun among heavenly bodies, or the heavy uranium
and thorium atoms. If the ether be a gas x it must naturally

accumulate from all parts of the universe towards the heavy
suns, just as the gases in the atuiosphcre accumulate in a drop
of water. Similarlv it will acemnul.ile towards the heaviest
atoms of thorium or uranium. 1/ siuli ii spcciiil acciimiilitl'uin
of ctlur atoms iihoiit tlu- iiioleciilcs of rndium and thorinin lie
adiiiissihlejlicij mifiht lie expcctid to cxiiiint fccuUar phenomena
dctci-mincd by the emission of 11 portion of this ether held hy
partielen of normal mean vehicily and by new ether enlerinf;
into the sphere of attraction. In short, the theory of tlic great
Russian chemist is not unlike in form that explanation sug-
gested l>v Sir William Crookes and Dr. Johnstone Stoney, .-ind
partly confirmed by Lord Kelvin, that the radiation of radium,
thorium. lS:c., is sustained by energy from without rather than
from within.

The lissential Kaffir. II is to the human interest of the
Kafhr that Mr. Dudley Kidd devotes himself in his valuable
and entertaining book, "The Essential Kaffir." (Adam and
Charles Black.) He uses the word Kaffir in its broadest
sense to include all the dark-skinned tribes of South Africa;
his information concerning the people of whom he writes is
intimate and varied, comprising the gleanings of a dozen years,
repeated visits to their tribes, visits in which he associated
with tliem in terms of intimacy, slept in their huts, watclied
thi-ir h.ibits of life and their social and religious customs,
memorialising them in many admiraljle and curious photo-
grai)hs which add greatly to the value .uid interest of his book.
There is, for instance, the photograph of the mother feeding
her baby with sour milk out of her hand, while a lean dog
watches the operation with symp.ithetic inteiest. In the next
])hotogr.iph the dog is buing utilised as a napkin to lick the
b.iby's face clean, while the mother holds its unwilling counten-
ance- steady with one hantl while she guides the dog's head
with the other. Mr. Kidd describes a night spent in a Kaffir
hut in company with the Kaffir family and such household
pets as a e.alf, a dog, roosting fowls, and others who shall be
nameless, but who could scale even sandbanks of Keating.
One feels as one reads that self-sacrifice in the cause of know-
ledge could go no further. Very interesting are the chapters
on Kaffir mental characteristics, on their nmsical instruments
and games, and on their religious beliefs. Of their mental
powers he notes the curious fact that the native children some-
times absorb knowledge with a singular precocity, but as they
develop their brains, as it were, seem to stop growing, tlieir
energies appear to be absorbed in their bodily development, and
whether caused by " meclianical formation of the bones of the
skull or not, must fie left to men of science to settle ; yet the fact
of stunted mental development remains." At the same timi'
the natives are remarkable for their extraordinary memory of
facts which interest them, such as the precedents in a legal
case. In a book where every page is interesting, an adequate
idea of its contents can hardly be given in so short a space.
All such people as the Kaffirs here described must rapidly
lose much of their individual character in contact with other
civilisations, and a book th.it crystallises their essential charac-
teristics from intimate observations lias a more than ephe-
meral interest.

Physical Chemistry in the Sciences, by Jacobus Vaii't Hoff.
(Chicago: The University Press.) To the Decennial publica-
tions of the University of Chicago have been added the series
of lectures which were delivered there by the German chemist,
Van't Hoff, and which deal with " Physical Chemistry in the
Service of the Sciences." The lectures, lucid, terse, concen-
trated, deal with Physical Chemistry in Pure Chemistry, in
Physiology, in Geology, and in Industrial Chemistry. T'loni
the last-named cliapter we may make an cxtnact which should
be very serviceable in bringing home to the British nation the
true reason for the growing strength of the German competitor
in industries that for many years were chiefly British. " There
exists in Germany," says Van't Hofi', " a very beneficial co-
operation between laboratory work and technical work. Both
go as far as possible hand in hand. After physical chemistry
had made several important advances, and was firmly estab-
lished in such a way th,al pure chemistry was assisted by co-
operation with it. Professor Ostwald judged correctly that this
co-operation would be valuable in teclinic.il directions. In this
beliefhe founded the I':iectro-Chemical Society. . . . All the
most conspicuous chemical industries of Germany are repre-
sented in the Society, which has its own organ of publication.
Nor has the stimulus to this co-operation come purely on the

100

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

scientific side. That it comes from botli parties may be seen,
for example, in the fact that a year ago Professor Goldschmidt,
of the University of Heidelberg, was asked by the Director of
the ' Badische .'\nilin-und-Soda Fabriken ' to give a series of
lectures on this branch of science before the chemists of the
factory, and did so with great success. .An opening up of new
points' of view, rather than immediate practical results, was
expected to flow from these lectures," all of which should

A plate of tin affected by Tin Disease ^enlarged one and a half times),

[Fwni ^'Physical Chem^ityy in the Sciences'^}.

strengthen a case, already overwhelming, for the establish-
ment of English Charlottenburgs. From V'an't Hoff's lecture
on Industrial Chemistry, «e take also a plate illustrating a
curious so-called disease of tin. It is rather a transition of
tin from one form to another, and has been recognised as of
actual occurrence since the time of .\ristotle. Van't Hoff de-
scribed the beautiful methods, largely due to the investigations
of Schaum and Cohen, by which the conditions which influence
this extraordinary change have been determined.

BOOK NOTICES.

Geometr}'. In addition to •' .\ School Geometrv (Parts
I.— IV. ; IV., V.)," by H. S. Hall, M..\., and F. S.'stevens,
M.A. (Macmillani, which we received last month, and which
provides a course of elementarj' geometry based on the recom-
mendations of the Mathematical Association and on the
schedule recently proposed and adopted at Cambridge, we
have received also " Elementary Geometry " (Parts I. and II.),
by Cecil Hawkins. M..\. (Blackie), which departs e\en more
boldlv than other works based on the tenets of mathematical
reform, and which, with practical illustrations, takes pupils
and classes, not through the routine of Euclidian propositions,
but acquaints them by progressive stages with the ascertain-
able properties of '• Intersecting Straight Lines," '• The
Triangle," " The Circle,'' " Polygons," and so on to areas and
to numerical theorems treated numerically.

Domestic Economy Reading Books, \ol. il., "The Marshfield
Maidens and the Fairy Ordma," by Mrs. W. H. Wigley
(Thomas Murby, 3, Ludgate Circus Buildings, E.C.). — Simple
lessons in household duties are conveyed in narrative form.

Logarithims for Beginnings, by Charles PickworthlWhittaker
and Co., 2, White Hart Street, E.C.). — A simple introduction
to the study of the subject, intended to give a more detailed
and practical explanation of logarithms and their \arious
applications than is to be found in text-books on algebra and
trigonometry.

Worked Problems In Higher Arithmetic, by W. P. Workman
and K. H. Chope (,W. B. Clive, University Tutorial Press). —

A collection of problems in higher arithmetic, intended espe-
cially for students who are preparing for Civil Service E.xa-
minations. It will also be of service to teachers.

Tables of Multiplication, Division, and Proportion, by Robert
H. Smith. M.I.M.E. (Archibald Constable).— These elaborate
tables will be useful in the ready calculation of quantities and
costs, estimates, interests, wages and wage premiums, Li;c.

The Story of Creation, by Edward Clodd (Watts and Co
Sixpenny Edition, with numerous illustrations and good type).
— It gives an account of the theory of evolution in clear and
popular form, dealing with the distribution of matter in space,
the past life history of the earth, present hfe forms, the origin
of life and of species, and social evolution.

An Agnostic's Apology, and other Essays, by Sir Leslie
Stephen, K.C.B. (Watts and Co. Sixpenny Edition.) — Con-
tains Essay on " Materialism," Newman's " Theory of Belief,"
■■ Toleration."

Remarkable Comets, by William Thynne Lynn, B.A.,
F.R..A.S. (Sampson Low, .Marston, and Co. New Edition). —
It reviews briefly the most interesting — perhaps we should say
the most popular — facts in the history of Cometary .Astro-
nomy.

A Safe Course of Experimental Chemistry, by W. T. Boone,
B..-\.. B.Sc. (W. B. Clive, Unisersity Tutorial Press).— .\ short
course of chemical experiments, designed to train students in
solving elementary problems by experiment, in accuracy in
their work, and in reasoning from observation. It is espe-
cially intended for the London matriculant who intends to
take the Intermediate Science Examination, or for students
in training colleges who have to take the prescribed course in
general elementaiy science.

Second Stage Botany, by J. M. Lowson, M.A., B.Sc, F.L.S.
(W. B. Clive. University Tutorial Press). — This is an adapta-
tion of the •■ Text Book of Botany " to the requirements ot the
second stage examination of the Board of Education, South
Kensington. The first part of the book deals with morphology,
histology, physiology ; the diagrams and illustrations are
numerous and clear, and will be very helpful to students.

Modern Navigation, by William Hall, B..\. (W. B. Clive,
University Tutorial Press), is intended primarily as a text-book
for students of navigation and also as a handbook for navi-
gators. It will be found useful in the various examinations of
the Royal Navy, the Mercantile Marine, and the Board of
Education. The explanation of compass deviations and
tides will introduce the student to more detailed works on the
subject.

Pocket Edition of the Works of John Ruskin (George .\llen).
— A small and pretty edition of Ruskin reprints, light to hold,
and pleasant to read. '• Sesame and Lilies," which deals
with ''The Mystery of Life and its .Arts," and insists that
'• those of us who mean to fulfil our duty ought first to live on
as little as we can ; and secondlj' to do all the wholesome
work for it we can, and to spend all we can spare in doing all
the good we can."

The Crown of Wild Olive ; Essays on '■ Work and War and
the Future of England," and " Lectures on .Art" — Essays 011
the Relation of .Art to Morals and the Relation of .Art to
Use. These three volumes contain some of the most
strenuous common-sense and right-thinking in Ruskin's
works.

Messrs. John Wheldon and Co., of Great Oueen Street, have
issued a clearance catalogue of a miscellaneous collection of
books. The volumes include works on botany, entomology,
and ornithology. There are especially to be noted some
works on fungi and publications relating to meteorology.

Messrs. Isenthal's new catalogue is well worth attention for
the completeness of the Rontgen-ray and allied apparatus
which their manufacturers ofl'er. The very large and greatly
increasing numbers of devices used in electro therapeutics
and in the new methods of the light treatment of disease are
specially noticeable.

Messrs. Harry W. Cox's new catalogue of X-ray and
high-frequency apparatus includes an extension of their
pre%iously issued practical hints to beginners. These hints,
covering work with X-ray coils, mercury and other interrupters,
and describing the best methods of connecting rheostats and
charging accumulators from the mains, are extremely useful,
and mucli to the point. They add distinctly to the % alue
and interest of the catalogue.

May, 1904.]

KNOWLEDGl' cS: SCIENTIFIC NEWS.

101

BOOKS RECEIVED.

A Sysleraatic Survey of the Organic Colouring Matters, l>v A. G.
Green. F.I.C., F.C.S. ^MacmilUii.) .-is. net.

My Airships, by .\. Santos Dmnont. (Giant Richards.')
Illustrated : 6s. net.

Five Years' Adventures in the Far Interior of South Africa, li\-
l\.("iordonl"innMiin.i;. (John Mnrray.) Illustrated; .;s. 6d.net.

Radium and all About It, by S. Hottone. (Wliittaker cS: Co.)
Illustrated : is. net.

A Text Book of tieology, by W. Jerome Harrison, I'.G.S.
(Blackie Cv: Son.) Illustrated :' .^s. 6d.

Dyes, Stains, Inks, Varnishes, i'olishe-, &c., In- Thcmias Holas,
F.C.S.. I-M.C. iDaubarn A: Ward.) Illustrated: 6d.net.

Metal-Working, l)v [.C. I'earson. (Murray.) Illustrated. 2s.

Practical Slide Making, by G. T. Harris! F.K.P.S. iIlitTe.)
Illustrated : is. net.

Phylogeny of Fusus and Its Allies, by .Vniadens W. Grabau.
(Smithsonian Institution.)

Researches on the Attainment of Very Low Temperatures, by
Morris W. Travers, D.Sc. (Smithsonian Institution.)

Nature's Story of the Year, by C. .V. W'itchell. ( Mslier Lnwin.)
Illustrated : 5s.

Notes on the Composition of Scientific Papers, by T. C. .\llbult,
M.A., M.D., ,.S;c. (M.icmillan.i js. net.

TKe AitcKison Prism Field Glasses.

The .■\itehison Prism Field Glasses, specimens of which have
been sent to us for review, represent a considerable .adaptability
alike of mind and of method on the part of British opticians.
The eftectiveness and popularity of the Continental prism
sjlasses were such as to leave no doubt in the mind of
opticians that in imitation lav the only form of successful
competition, and that to imitation must be added improve-
ment. In consequence a t;reat deal of money has been spent
with this end in view; and the .\itchison glasses represent a
very gratifying measure of achievement as a return on the
outlay of expense and ingenuity. The principal features of the
glasses that we have before us are the use of large object
glasses, variable diaphragms, and improved means of
focussing. With the larger object glasses are used prisms and

I«PR1SM-/XI?

The Black Line with arrow head shows the path of rays of light in
the New Aitchison Prism Field Qlass.

lenses of a higher index of rtfr.iction than ordinarily employed.
The prisms are very much larger than in the German glasses.
The introduction of variable diaphragms is a quite nt'w
departure in the construction of field glasses. A p.air of Iris
diaphragms are in this case introduced into the tubes close to
the object glasses and ground together so that they are
worked simultaneously from the toothed wheel on the central
pillar. By this means, as in tlie photograpliic camera, .all
unnecessary rays can be cut off when the light is brilliant,
and in dull weather and at night the whole available aperture
of the object glasses can be used, thereby effecting an immense

ad\ .intage over the old form with fixed diaphragms. Another
benefit is the rigidity of the body, which is secured by
casting the two lubes and crossbars in one piece inste.id of
building them up in separate parts as hitherto

University College Lectures.

Th- /ollou'iiig Courses 0/ Lectuycs wilL he dclivo'c.i duri)h^ May

at the University CoUcj^e, Loiu/oii.
Coursoof K) Lectures on the HISTORY OF M()Dl';im

I'lIILOSOl'llV, by Mr. .\. Wolf, M...\. First

Lecture, .\pril 26th, 4 p.m.
Course of Lectures on COM PAR ATI Vb: LAW, by

I'rof. Sir John Macdonei.i,, ^L.\., LL.L)., (".]].

Commencing April 26th.
Courseof 10 Lectures on the HISTORY OF ARCHL

TLCTUKAL DICXliLOPMlCNT, by I'lol. F. M.

SniHsoN. Commencing April 2jnd, 11 a.m.
Introductory Course of 12 Lectures on IDICALISTIC

ETHICS, i)y Rrof. G. n.wvts Hu ks, M.A., Ph.D.

Tuesdays and Thursdays, 5 p.m. Commencing

April 26tli.
Course of liight Lectures on POST-ARISToTELl AN

PHILOSOPHY, by Prof. G. JXwves Hicks, M.A.,

Ph.U. Tuesdays, 4 p.m. Commencing May 3rd.

,/*^ •'^ ^^ "^^ -^^

Recent Patents.

FIG. 3

I9,6s2. Electricity, measuring. Naluek, F. II., and
-Xaldek linos, AND Tumnsox, i-\, yueen Street, London.
Sept. s.

Currtnl Meiers. — An am-
meter or volt-meter, having
a soft-iron needle movable
about an axis at right-
angles to the magnetic axis
of a coil .;, is provided with
a magnetic shield h, //* of
soft iron or mild steel,
which may be enclosed in
an ordinary cast-iron cas-
ing. The shield has the

form of a cubical box surrounding the coil, its ends being open. It

may be in two parts, as shown, one overlapping the other tightly.

Or it may be in one piece, the ends of which are overlapped.

23. 73'- Variable=speed mechanism. Mhisckkk Smith, W,
and Mkisciikk-S.mhii, (i V . lioth nf 7, Kiie DruucM, I'aris.
Oct. JO

KL-latoi to variable-speed mechanism,
particularly for use with motorcars and in
connection with friction-ratclietdriving-ap-
paratus, such as isdescribed in Specification
No. 20,135, A.D, igo2. A crank « mounted
on a shaft c has the crank-pin /( mounted on
anut/, wliich can move on ascrew/Mn the
crank ii for producing a variable throw. The
screw /( terminates in a worm-wheel I,
which gears with the worm c on a sliort
shaft carrying a pinion d. The piniun d
engages with both a loose toothed wlieel/,
and a loose inner toothed ring g. The
wheel / is fixed to the disc w so that either
/org can be retarded by a brake. When
either is retarded, the piiiicjii d is caused
to rotate, and, througli it, the screw A and
the nut i relatively to the crank u.

102

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

33.733- Photography.

Oct. 30.

Beck, C, 68, Cornhill, London

Ciimciiis : rallir slidt's : sJiullcis. — Relates to a camera with roller
slide and two shutters, one at the focal plane and one at the lense.
The camera is shown in Fig. i, with the bellows removed The
rollers 12, 11 of the bUnd shutter are mounted between rollers i of
the roller slide. The front 3 is mounted on metal runners 5 fixed in
the middle of the hinged base-board 7. To fold up the camera, the
front 3 is pushed back, the stays 6 are disconnected, and the base-
board 7 is folded up on the back. The camera is supported by a
metal frame 8, which is pivoted to a base-board 7 so that it can be
turned over the end of the latter in folding up the camera. The
focussing is done by moving an arrow on the front along a scale of
distances on the base-board, lines being marked on each side of the
arrow to indicate depths of focus for tlie different lense apertures.
The lense shutter, which consists of two hinged plates 15. is closed
while the roller bhnd shutter is being set by turning the button 25.
To make an e.xposure, the button lO is depressed, a movement
which, acting through the links 17, 18, 20, or through a ffe.xible
shaft, opens the shutter 15, then lifts the pawl 14, which releases the
roller blind shutter, and makes an e.xposure. The blind shutter has
two apertures, one equal in size to the aperture 2 in the back of the
camera, and a narrower aperture for more rapid exposures. There
is an adjustable stop arrangement in the blind roller 12 liy means of
which either of these apertures can be used This stop arrange-
ment consists of an axial screw actuated by the roller 12 and thus
moved lengthwise, till it comes against a stop and arrests the
shutter. For a time exposure, the large aperture of the roller blind
is brought opposite the opening 2 and held there by the pawl 14,
which is locked by a sliding plate 81 The time e.xposure is then
made by the front lense. A method of holding the spools of roller
slides so that they can be easily removed or inserted is described
A spring is placed at one end of the spool so that it can be pushed
back to liberate the other end.

23,858. Therino=electric batteries. Johnson, J Y , 47,
Lincoln's Inn hields. London — (ir,i//'i~ Co., A.: Bli-ii-lnlnissf,
Fianhfi'it-on-tke-Muiii. Ccimnny). Oct. 31.

FIG. I

Consists in the employment of special
shaped bars for use in a thermo-electric
battery. The bar 6, consisting of a
nickel-copper alloy, is bent as shown and
has a barr cast on one end, this bar being
an antimony-zinc alloy to which iron or
cobalt has been added, in order to raise
its melting point and to increase its
mechanical strength. A copper strip;/ is
attached to the nickel at its cold end, to
act both as a support for, and to facilitate
the cooling of. the nickel, whilst a copper
plate is attached to the antimony for the
same purpose. The short horizontal and
vertical arms of nickel, which are heated
to produce the thermo-electric current,
may be replaced by silver, or an alloy of
copper and silver, or copper coated with
silver or gold ; or the short horizontal
arm alone may be so replaced.

12, Kaiserstrasse, Nurem-

9, 749. Photography. Beck, F

berg, Germany. Sept. 9.
Ciimeni s^i;«?s.— Relates to a supporting-device for hand cameras,
which is detachable from the
camera. It consists of a base-
board in two parts ii; b hinged at c.
At the back of the part j is pivoted
a bracket d having a sliding bar e
with an arm /, which is pressed
down on the camera back g and
7 Jll LU '-^i' !! J 'L clamped by the lever /;. The

'i i, ^ nXlXP'^^J front / of the camera is held by a

spring clip which is pivoted to the
front of the part h. When the sup-
port is not in use, the brackets d. i
are folded down flat, and the parts
I', b are folded together on the
hinge r. The camera may be laid
on its side on the support, when the front I rests on the block m,
and the arm / is pushed further down.

23,969. Arc light projectors.

Engelsmann, a., II, Armin-
strasse, Stuttgart, Wiirtem-
berg, Germany. Nov. 3.
Rijii-cters for projecting light
from alternating-current arc
lamps The light from the car-
bons />, I" is reflected by two
annular parabolic mirrors d, f,
that falling on the mirror /being
reflected again by an annular mir-
ror 4', within the mirror <l.

N-Rays

Stored up by
Bodies.

Certain

III the course of hi.s investigations of the N-rays, Professor
Blondlot, as pointed out in a note just read before the French
Academy of Sciences, happened to state an interesting phe-
nomenon. N-rays being produced by an Auer burner enclosed
in a lantern, would traverse first one of the walls formed by an
aluminium foil, to be concentrated afterwards by a quartz
lease on phosphorescent calcium sulphide. The Auer burner
ha\ing been extinguished and taken away, the phosphorescence
would persist with nearly all its brilliancy, and on interposing
a lead screen or moistened paper or else the hand between the
lantern and the sulphide, the latter would be darkened ;
nothing was thus changed by the Auer burner being taken
away but for a gradual decrease in the strength of the effect
observed. Twenty minutes afterwards, they would still per-
sist though being nearly insensible.

On closer investigating, the conditions of this surprising
phenomenon, Blondlot soon noticed that the quartz lense had
itself become a source of N-rays; as, in fact, this lense was
taken away any action on the sulphide would disappear,
whereas by approaching the lense, the sulphide was made to
take a higher brilliancy. The author then exposed a quartz
plate 15 mm. in thickness, the surface of which was a square
of 5 sq. cm. to tlie action of N-rays given oft" from an Auer
burner through two aluminium foils and black paper, when the
plate would become active like the lense ; as, in fact, the sul-
phide was approached, a phenomenon would be observed as
if a darkening veil were taken away from it. In all these
experiments the secondary emission from the quartz adds its
effect to the N-rays directly emanating from the source. This
secondary emission resides throughout the mass of the quartz,
and not only on its surface, as by placing successively several
quartz plates one on another, the effect is found to augment
with each added plate. Islandspar, fluorspar, glass, &c.,
show a similar behaviour. A Nernst lamp filament will remain
active for several hours after the lamp has been extinguished.
A gold piece, on being laterally approached to the sulphide,
subinitted to the action of N-rays, would take a higher bril-
liancy ; lead, platinum, silver, zinc, &.C., would produce the

May, 1904.]

KXOWT.F.DGE \- SCIENTIFIC NEWS.

103

same effects. These actions would persist after the extinction
of the N-rays. as in the case of quartz, though the property of
emitting secondary rays does not penetrate liut slowly the
m.asses of metal.

Aluminium, wood, dry and moistened paper, paraffin, &c.. do
not show this' property of storing up Nrays. Calcium sul-
phide, on the other hand, will exhibit the same effect. This
phenomenon accounts for the fact formerly observed by the
author that the increase in phosphorescence under the action
of N-rays require a cert.ain time both to be produced and to
disappear. .-Vs. in fact, N'-rays .are stored up, the different
parts of the mass of sulphide 'will mutually strengthen their
phosphorescence; as. however, the storing up is progressive,
and as, on the other hand, the amount .stored up is not
e.xhausted instantaneously, the effect of N-rays falling on
phosphorescent sulphide must increase slowly, .and on being

cords of two brothers, dead of hereditary ataxia. Coloured
plates illustrate the lesions of the spin.al cord.

The article in question is extremely interesting to neuro-
logists and medical men, and should be studied by those
seeking the truths of well-deep neurological liter.ature.

To the gener.al scientific reader, who does not wish for
technical details, the .article brings home the lessons of care
that parents should take in inquiring into the antecedents of
those about to m.arry.

Dr. Sanger Brown says, and truly says : '• Hereditary ataxia
is a disease which may be traced through several — at least
four — generations, increasing in extent and intensity as it
descends, tending to occur earlier in life, .and to advance more
rapidly. It usually attacks several members of the same
family. It occurs most frequently between the .ages of 16 and
35. It shows no marked preference for sex. but it descends

eliminated their effect cannot but progressively be extin-
guished.' 'Certain stones picked up in a court where they had
been exposed to the action of sun rays in the afternoon would
give off spontaneously N-rays. preserving this activity for four
days without any appreciable decrease. The surface of these
bodies should, however, be very dry, the slightest layer of
water being sufficient to stop the N-rays.

Hereditary Ataxia.

Among the latest volumes of the Decennial Publications of
the University of Chicago is an interesting article by
Lewellys F. Barker,* which includes a detailed description of
the gross and microscopic findings in the brains and spinal

'"A Description of the Brains and Spinal Cords of Two Brothers,
Dead of Hereditary Ataxia of the Series in the Family Described by
Dr. Sanger Brown," by lewellys F Barker. 'The Decennial
Publications of the University of Chicago.

Family Tree of Hereditary Ataxy.

through females four times as frequently as through males
There is always considerable inco-ordination of all the volun-
tary muscles, and a sluggishness of the movements which they
produce, when the disease is well established. This is
usually noticed first in the muscles of the legs, but in a few
months or years extends to the arms, face, eyes, head and
organs of speech. Sometimes it occurs first in the upper
extremities, and sometimes in the organs of speech."

There is little to be noticed in the macroscopic appearance
of the cord as shown in the illustrations given, but micro-
scopically, there is revealed marked degeneration in the grey
and white matter.

The matter contained in this publication is accurate, and
shows a profound insight and knowledge of the disease treated.
By its study, we are enal)led to know with certainty the
neurone-systems principally involved in the individuals who
are affected, though we are as yet entirely ignorant as to why
just these neurone-systems should be picked out. The letter-
press is clear and large, and the plates are extremely well
done. We must congratulate the University of Chicago Press
Illinois, on the first series of their publications for the
University of that city. — S.G.M.

I04

KNOWLEDGE & SCIENTIFIC NEWS.

[May, 1904.

Conducted hy F. Shili.ington Scales, f.r.m.

MITES.

Cecil \\'ARBrRTOx, M.A.
Why do so few people collect mites ? If we come to think
of it the waste of energy among collectors is appalling,
simply because nearly all are content to follow beaten
tracks, where the chances of new discoveries are rare,
and the same old observation is made for the fifty-
thousandth time. There must be hundreds of people in
England at this moment whose hobby is the microscope,
who are skilful in the manipulation of small objects, and
possess the collector's instinct, but whose imagination
does not get beyond making neat preparations of dia-
toms or rotifers, or Foraminifera. And all the time here
is a group of creatures ideal for the purpose, of great
intrinsic interest, and concerning which a great deal
remains to be discovered. Anyone who attacks the
Acari with enthusiasm is pretty sure to add not one but
many mites to the sum of human knowledge.

Many, no doubt, are deterred by the very fact that so
little is known about these creatures. A moth, or a
beetle, or a rotifer can generally be identified wath com-
parative ease, because the researches of innumerable
workers in these groups have been reduced to a form
convenient for reference ; but how is one to identify a
mite ? There is force in this argument, of course, though
if the difficulties are greater, the chances of distinction
are greater in proportion. In one family of the Acari,
the Oribatida- or " beetle-mites," moreover, this difficulty
does not exist. Just consider, for a moment, the follow-
ing facts.

Hardly a single Oribatid mite was recorded as having
been captured in this country before 1879. In that year
Mr. A. D. Michael published the first of a series of
papers on these creatures, which he has since summed
up in an admirable monograph,'' fully illustrated, and
containing every kind of information which can be of
use to the collector. In this about a hundred British
species are described. Remember that he was absolutely
a pioneer in the subject, and worked at it almost single-
handed in the leisure hours of five years of a busy pro-
fessional life, and that very little indeed has been done
since. He has given his followers a magnificent start :
but is it likely that the mine he discovered and worked
so enthusiastically is anywhere near exhaustion ?

It would appear at first sight that the search for
creatures which seldom e.xceed a millimetre in length,
and are frequently very much less, must be laborious
and irksome. The exact opposite is the case. Cer-
tainly it would be out of the question to go out into the
open, armed with a lens, in search of individual mites, but
there is not the least need for such a proceeding. These
mites live under loose bark, in decaying wood, and
especially in lichen and moss. The necessary equip-
ment, then, for field work is not a lens at all, but a bag,
or several bags. Thus armed the collector starts out to
visit some likely spot that has occurred to him, a moss-
grown wall, or a coppice where the trees are grey with

• Publications of the Royal Society, 2 vols.

lichen, and the ground carpeted here and there with
patches of moss, and with such materials he fills his
bags, bringing them home to work over at leisure.

The study or "den" is now cleared for action. The
apparatus consists of a pocket-lens, some large sheets of
white paper (the white under-surface of remnants of
wall paper is excellent for the purpose), a camel's hair
brush, some ordinary microscope slides, and a low-power
microscope arranged for opaque objects. I know of
nothing better for the work in hand than a Stephenson's
binocular with the one-inch objective. Portions of the
moss are shaken out over the paper, and the dihris
allowed to remain undisturbed for a minute or so. Then
most of the creatures shaken out of the moss will have
found their feet, and will not be dislodged if the general
litter is gently tilted off or blown aside. Numerous little
specks are sure to be left adhering to the paper, and a
moment's observation will show that some of them are
slowly moving. Then the lens is brought into play,
and the moving speck examined, and if it seems to be
one of the creatures sought, it is transferred to a slide by
means of the brush, and placed under the microscope for
a closer study. But there are many other moving
specks, and time is too precious just now to spend more
than a moment or two o\er a single example, so w'e
lightly place a cover-slip on his back, and thus loaded he
is not likely to have moved \ery far when we ha\'e
leisure to look at him again.

If the material is good, the hunt will be found exciting
enough while it lasts, and the '• bag " will be a certain
number of tiny creatures making ineffectual efforts to
walk along on the slippery surface of the glass slides
under the superincumbent weight of the cover-slips.
What is to be done with them ? Well, the more
thoroughly they can be examined while alive, the better,
but those that are selected for the cabinet have to be
killed and preserved in some way or other. In a
collection of mites it is very desirable to have a double
series of specimens, one series mounted as opaque
objects, and the other rendered transparent. Whichever
their destination, the preliminary operations are the same.
The best w'ay to kill them is to pop them into boiling-
water. It sounds brutal, but it is instantaneous, and it
has the advantage that it causes many species to extend
their legs, and those that are not so obliging are generally
in a more or less limp condition, and pretty easily mani-
pulated. Now is the moment when the skill of the
operator comes in. The mites are taken out of the
water with the brush, and placed on white blotting
paper. Then a single specimen is placed on a slide,
turned on his back, and his legs arranged in the desired
attitude under a dissecting microscope. A cover-slip
keeps him in the proper position, and a drop of 2";',
solution of formalin is run in, a slight weight, such as a
flattened shot, being superimposed to prevent the legs
from curling up again. For the even distribution of the
weight it is well to make a tripod with three specimens
and the cover-slip.

Next day the creatures will be found to be rigid, and
ready for dry mounting. If they are to be made trans-
parent, carbolic acid is substituted for the formalin,
which is remo\ed by means of blotting paper as the
acid is added. Some species will require a very much
longer time in the carbolic acid than others, but they
simply remain in till clear, when they are ready for
mounting in Canada balsam, and the collector then has
one specimen which shows how the animal looks when
alive, and another in which minute points of the exter-
nal anatomy may be studied. In this particular group
of mites the chitinous cuticle is generally well-developed,

May,

1904.,

KNOWLEDGE Ov; SCIHXTIFIC XEWS.

I "5

and the creatures lend th(>msolvi'> excellently to dry
mounting.

\'ery wet moss will not yield up its inhabitants on
shaking, and it must be somewhat dried — not too rapidly.
If there is a great deal of coarse ih'hn's, as is sometimes
the case, there is a danger of all the mites being swept
off as the paper is tilted, and to obviate this it is not a
bad plan to use some wide-meshed muslin as a sifter.
The mites and the smaller particles of earth readily
pass through the meshes, and can be distributed exenly
over the surface of the paper with better chances of
successful hunting.

(7V be continued.)

Royal Microscopical Society.

March 16.— Dr. Diikinfield H. Scott. F.R.S.. President, in
the chair. Prof. .\. K. Wright communicated the purport of
his paper " On Some New Methods of Measuring the Magni-
fying Power of the Microscope and nf Lenses Generally." He
described also the piece of apparatus which he had invented
for taking the magnifyiug power of the microscope and for the
rapid measurement of microscopic objects, which he termed
an Eikonometer. It is placed over the eyepiece, without dis-
turbing any of the adjustments of the instrument, and the
object on the stage can then be instantaneously measured.
The Secretary read a short note by ^fr. I£. H. Stringer "On
the Separation of L"ltra-\'iolet Light." Mr. .\braham Flatters
exhibited on the screen a series of 60 hand-painted lantern
slides illustrating botanical histology. The slides were photo-
micrographs of the actual micro-sections coloured accuratelv
to represent the staining, and were much commended.

Queckett Microscopical Club.

The 412th ordinary meeting of the Club was held on
March iS, at 20. Hanover Square, \V., the new President,
Dr. Edmund J. .Spitta. V'.P.K.A.S., in the chair. The Secre-
tary announced that the new catalogue of the Club's Library,
containing some 1300 volumes, had been published, and was
on sale at the price of one shilling.

Mr. T. G. Kingsford exhibited and described some glass tanks
which he had constructed by a new method which did not
involve the use of cement. These were primarily intended
for use as light filters or screens, but they were also adapted
for examination of pond life. The sides were formed of glass
discs (clock glasses) kept at the desired distance by blocks of
.rubber cemented to a rubber band. This rubber band formed
a lining to a similar l)aud of flexible metal, the ends of which
were drawn together by a screw. The pressure of the baud
upon the edge of the discs made a water-tight joint.

The Secretary read a note on the resolution of Amphiphuva
pellucida, by Lieut. -Col. John Thompson, of Brisbane.

Mr. D. J. Scourfield read a note, communicated by Dr.
Vavra, on two Phyllopods from Bohemia, describing the life-
history of these curious Entomostraca.

The Secretary then read extracts from a highly-technical
paper by Mr. T. B. Kosseter, F.R.NLS., "On the Genitalia of
Taenia Sinuosa," the remainder of the paper being taken as
read.

Ne^v Achromatic Condenser.

Messrs. J. Swift and Son have sent me for critical exai7iina-
tion a new achroniatic condenser of the form which is now
rapidly superseding the ordinary non-achromatic type, which

has so small an aplanatic cone as to be nearly useless for really
critical work. Messrs. Swifts condenser is achromatic, its
power is ,'„ of an inch, and its aplanatic cone is between 95
and -96, with a numerical aperture of i. With the top lens
removed the power is about ij inch, but the" aplanatic aper-
ture, as always happens under such circumstances, suffers

.accordingly. dro]iping to -4. The back lens is nearly i inch in dia-
meter. It is notgencrallyrealiscdtliattoobtainthe full aplanatic
aperture of condensers of so perfect a type a definite thick-
ness of slide must be used, and t" obviate this and .it the
same time enable the best results to be arrived at, Messrs.
Swift fit an improved form of correction collar to enal)le the
necessary adjustments to be made. Theprice of the condenser,
without mount, is 4.SS., and the correction collar is 15s. extra. ,

Notes and Queries.

I am glad to be able to announce with the present number the
resumption of the " Notes and Ouerics " column, which, owing
to circumstances beyond my control, but incident to the pres-
sure of other matter in the colunmsof this journal, has hitherto
been held over. In this cohnnn I shall endeavour, ,is hereto-
fore, to answer (as far as I am able) all (jnestions addressed
to me which are of general interest. I wish also, if possible,
to give an opportunity to my readers to publish short notes
on matters appertaining to microscopy, which may interest
them, or on which they may desire to interchange views,
though, of course, limitations of space will necessitate my
exercising a personal discretion in such matters. On many
occasions, bv the kindness of various correspondents, my
predecessor. Mr. Cross, and 1 have also been able to distribute
micro-material to applicants, and I ho]ie that any readers who
may have material of this sort suitable for distribution will
give their assistance in this respect.

Magnification of Objectives and l;\epieces. (Major C. W.
Ta ruAM, I")(voiipor).)

A ,', -inch objective professes to give an initial magnifica-
tion (without eyepiece) of 120 diameters with a lo-inch tiihe.
If it is corrected for and used with a shorter tube it will give a
proportionately lower magnification, i'./,'.. with a 6-inch tube
the initial magnilication will be -,'v-ths of the foregoing, i.e., 72
diameters. This magnification is increased by that of the eye-
piece, which is, of course, itself unchanged, whatever the tube-
length. Thus a -/.-inch objective used with an eyepiece that
has itself a magnifying power of 5 will give with a lo-inch tube
120 X 5 = 600 diameters. With a 6-inch tube the total mag-
nification will be 120 X — X 5 = 360 diameters. Now come
10

in two qualifications: First, that the objective is never quite
in accordance with its professed magnification (based on the
equivalent focal length), and is generally considerably higher
second, th.at the oculars ;ils<i are not what they profess to be,
and, moreover, that many makers will persist in rating them as
if they and not the objectives varied in power according to
variation in tube-length. For instance, your compensating
eyepiece 12 may not be 12, but about half as nuich again,
Zeiss assuming that tlie /.^-inch gives 120 magnifications at
6.^^ inches, and that this is multiplied by a 12 ocular, making a
total of 1440 diameters, whereas, as a m,atter of fact, with this
tube length, the 1440 diameters is made up of objective mag-
nification 72 X ocular magnification 20 or therealiouts! The
compensating eyepieces for the long tube are therefore marked
with their proper magnifications, and those for the short tube
are the same oculars marked down .as if they were 6j times
what they really are. With regard to testing the magnifica-
tions of objectives and oculars yoiuself, you will find detailed
instructions in my article in the I'ebruary issue. If you do
not follow any point write to me again. Meanwhile, I need
scarcely say that any power ocular can be used with any
objective, provided the fatter will bear it.
Mounting Diatoms in (ium Styrax and Monobromide of Naph-
thalene. (G, \. F.VANS, P.ristol.)

I think you will find all that is necessary for mounting
diatoms in these highly-refractive media in Carpenter, page 521
(8th edition): The gum styrax can be dissolved in benxole or
xylol ;ind used as Canada balsam is used, save that more care
must be taken to evaporate the benzole, or other solvent,
before covering with the cover-glass. Monobromide of n.iph-
thalene is solulile in alcohol and ether, but in Carpenter it is
recommended that the mount should be run round with a ring
of wax, then ringed with Heller's porcelain cement (which is
not familiar to nie), and finally closed with shellac.

[Communications and enquiries on Microscopical matters are invited,
and should he addressed to F. Shillinglon Scales, "Jersey," SI,
Barnabas Road, Cambridge.']

io6

KNOWLEDGE & SCIENTIFIC NEWS.

[May 1904.

The Face of the Sky for
May.

By W. Shackleton, F.R.A.S.

The Su.n'. — On the ist the Sun rises at 4.35, and sets
at 7.20; on the 31st he rises at 3.52, and sets at 8.4.

Sunspots and facuhe should be looked for whenever- it
is fine ; the positions of the spots with respect to the
equator and pole may be derived from the following
table :—

Dale.

.\Nis inclined to W. from
N. point.

Centre of disc, S of
Sun's equator.

May I . .

10 . .

20 . .

,, 30 ..

24' 16'
22° 22'

19° 36'
16= It'

3° 58'
3° 0'
1^52'
0" 4 1 '

The Moo.\ : —

Date. Phases.

H. M.

May 7 ..

.. 15 ■•

22 ..

,. 2g ..

'Z Last Quarter
• New Moon
'1 First Quarter
G Full Moon

II 50 a.m.

10 58 a.m.

10 ig a.m.

8 55 a.m.

May 8 ..
22 . .

.\pogee
Perigee

4 18 p.m.
10 30 p.m.

Occulta-tions.

There are only two occultations of fairly bright stars
observable at convenient hours during the whole month.
The particulars are as follows : —

Date.

Star's Name.

.Magnitude ^''-PP- ^^-PPf-

May 17
,, 21

130 Tduri
0 Leon is

55 7.27 p m. 8,20 p.m.
38 9. I p m. g 26 p m.

The Planets. — Mercury will be observable for the
first four or five days of the month ; he should be looked
for in the N.N.W. immediately after sunset at about an
altitude of 15". He is bright enough to be visible to the
naked eye, but any slight optical aid will be of great
assistance in detecting him in the strong twilight. The
planet moves so rapidly that he is in inferior conjunction
with the sun on the 13th.

\'enus is a morning star throughout the month, rising
only a short time in advance of tlie sun, and being for all
practical purposes unobservable.

Mars is in conjunction with the sun on the 30th, and
is therefore out of range.

Pallas is in opposition on the i6th, when the magni-
tude is 8-5. On this date, the minor planet has the same
R..\. as 7 Herculis, but is situated 6" north of the star.

Jupiter is a morning star, rising about 3 a.m.

Saturn is also a morning star, rising about 1.20 a.m.
near the middle of the month ; he is in quadrature with
the sun on the nth.

Uranus rises about 11.30 p.m. near the beginning of
the month, and about g.30 p.m. towards the end of the
month. The planet is situated 4 mins. E. of 4 Sagittarii,
and, observing with a low power eyepiece, can be seen
in the same field of view as the star.

Neptune sets too soon for observation.

Meteors. — The principal shower during May is the
Aqnarids. This maybe looked for between May i-6;
the radiant being in R.A. 22 h. 32 m., Dec. S. 2°., near
the star -n Aquarii.

The Stars. — About 10 p.m. at the middle of the month
the followdng constellations may be observed :

Zemth . Ursa ^lajor.

North . Polaris ; to the right, Draco and Cepheus ;
below, Cassiopeia ; Perseus to the left.

South . I-]o6tes and \'irgo, Avcturus and Spica a
little E. of the meridian ; Leo to the S.W.

West . Gemini and Cancer ; Taurus to N.W. ;
and Procyon to S.W.

East . Lyra (Vega), Corona, Hercules, and

Ophiuchus ; Cygnus to N.E.,and Scorpio in S.E.

Telescopic Objects: —

Double Stars: — ^ Libra?, XI\'.'' 46™, S. 15- 39', mags.
3, 6 ; separation 230" ; very wide pair.

ff Coronae, XVI.'' ii"", N. 34° 7', mags. 6, 61; separa-
tion 4"'4 ; binary.

a Herculis, XX'II.'' lo", N. 14° 30, mags. 2i, 6;
separation 4"-q. \'ery pretty double, with good contrast
of colours, the brighter component being orange, the
other blue.

{Herculis XX'H.^ 11™, N. 24° 57 , mags. 3, 8; separa-
tion 17".

Clusters. — M13 (cluster in Hercules) situated about
J the distance from t) to '( Herculis, and is just visible to
the naked eye. It is a globular cluster, and with a 3 or
4-inch telescope the outlymg parts of the cluster can
be resolved intu a conglomeration of stars.

•'^i ^*^ ^'^ ^*i ^^

Brass Stripping.

Electrolysis, which deposits surface films of metal, has lately
been put to an ingenious industrial use in stripping metals.
Professor C. F. Burgess records a method of stripping super-
fluous brass from the joints of bicycle frames by using an elec-
tric current with a solution of sodium nitrate. The firm which
has adopted the method used to make use of hand lalionr.
which damaged the tubes, and afterwards of chemicals, such
as potassium cyanide, which were expensive and slow. By
this reversal of the principle of electrolytic deposition the brass
can be cleaned off the tube joints in from five to forty-five
minutes at a scarcely appreciable cost.

Calcium as arv Industrial Metal.

Pkoff.ssor Borchers, of Aix-la-Chapelle, has succeeded, after
overcoming many difficulties, in producing calcium by a new
electrolytic process, by which, it is said, the metal can be ob-
tained at a very low cost. It is now being extracted on a
large scale, and there should be a great future before it, for,
while of very common occurrence, calcium possesses certain
properties, such as a great affinityfor oxygen.which should make
It a very desirable innovation in the iron industries. Exposed to
moist air the metal rapidly becomes coated with oxide ; but it
nevertheless possesses many characteristics which may prove
of value in the arts. It is fairly hard (harder than lead), can
be hammered into leaf, and is very light, having a specific
gravity of only 1-58, or much less than that of aluminium

KDomledge & Selentifie Neuis

A AlOXTllLY JOURNAL Ul- SCILiNCE.

Vol. I, No.

[new series.]

JUNE, 1904.

r Entered at
LStationers' Hall

]

SIXPICNC

Contents and IS'otices. — See Rage VII.

RoLdio-Activity acrvd
R^aLdium.

By W. A. SiiKNSTONE, I'.R.S.

II.

The discovery that radium gives ofT, unceasin'^ly, the
radiations discussed a little later, and the early observa-
tion that in many respects these resemble the Kiintgen
or X-rays naturally suggested that possibly a few
milligrams of radium miglit ad\antageously replace the
comparativelj' complicated equipment required for the
so-called X-ray photography, and accordingly this very
interesting side of the subject has excited some interest.
Whether radium rays will ever replace the usual
apparatus for the production of Rontgen rays remains to
be seen. But some very interesting results have un-
doubtedly been obtained, as my readers will gather from
the following series of very excellent radumi radio-
graphs which I am allowed to introduce by the kind
permission of Mrs. Gifford, of Chard, who has been
working on this subject with great success. The con-
ditions are given under each plate. Fifty milligrams of
highly-purified radium bromide in glass tubes were used.

Fig 6 — The radium salt was enclosed in two light bags. Exposure,
24 hours, at a distance of 9-65 cm. Medium plate. Most of the
objects will explain themselves. The rectangular figures at the
top are produced by blocks of glass, that to the right by ura-
nium glass The crystal near the larger block was fluor spar,
the amorphous mass at the bottom on the reader's right is Kauri
gum.

The trouble which arises in regard to the use of radium
salts for work of this kind, 1 am informed, is this : Thai
it is diflicult, if not impossible, to concentrate the acting
salt into a sufficiently small space. The radiations
used, in short, are too din'use.

Fir,. 7. — Taken under much the same conditions as 6, but througli
a plate of aluminium and with a 10 hours' exposure.

The distinctive characters of radium which were first
recognised were what are commonly known as " its
radiations." But almost more wonderful and mysterious
than these is the " emanation," which has been .so
carefully studied by Professor Rutherford, of Montreal.

The Radiations of Radium. — These have been classified
as a, /3, and y ray.';. The last resemble Riintgen rays.
They are unaffected by a magnetic field, and are intensely
penetrative, passing through sheets of lead of consider-
able thickness, and these rays alone of the radium rays
can penetrate the eyelids freely, so that they can be
identified by the sense of diffuse light, of which one
becomes conscious when a few milligrams of a radium
salt are held near the tightly closed eye in a dark room.

One of the greatest achievements in physics during the
latter half of the nineteenth century was the discovery,
by Prof. J. J. Thomson, of Cambridge, and his colleagues,
in the cathode stream of the Crookes* vacuum tube,
of particles so small that about 700 of them would be
required to produce a mass equal to that of an ;itom of
hydrogen. These particles carry negative charges of
electricity, and so are deflected by magnets; they will
pass through thin sheets of metal, cause damp, dust-free
air to form mist, and they make air conduct electricity.
They move with a velocity equal to one-tenth that of
light. They are often called " Electrons." * Now the

• This terra was originally applied to the charge of electricity

carried by an atom of hydrogen in electrolysis.

io8

KNOWLEDGE cV SCIENTIEIC NEWS.

(■June, 1904.

ji rays of radium exhibit just these properties, only
they move even more rapidly, sometimes, indeed,
several times as rapidly as the electrons in the cathode
stream, and are more penetrative. Hence the ,3 rays
may be considered to be " electrons."

The a rays were the last discovered. These are far
heavier than the others, and are very easily stopped.

Fig. S- — Taken without bags, at a distance of 4 cm. and with
5 hours' exposure. The dark shadow on the reader's left was
produced by uranium : above it was a crystal of fluor spar
The rectangle at the top was caused by glass, and the dark
object below this was a threepenny bit.

They can be deflected by powerful magnets, and the de-
flection is in the opposite sense to that of the rays of the
cathode stream, which shows they carry positive charges.
Sir \\'illiam Crookes has shown us how to recognise
them by letting them strike screens covered with phos-
phorescent zinc sulphide, as in the " spinthariscope."

Such substances as fluor-spar, kunzite, diamond,
willemite, and barium platino-cyanide become luminous

Fig. g. — .\ necklace of various jewels set in metal. No bag. Taken
with a rapid plate in three and half hours at a distance of 44 cm

if the rays of radium fall upon them, much as they do
under the influence of cathode rays, the effects produced
being exceedingly beautiful.

The Emanation of Radium. — If radium be heated strongly,
or if it be dissolved in water, a substance is given ofT which
mixes with gases, and which, when freed from impurities,
has the properties of a gas. This substance can be con-
densed at the temperature uf liquid air in a glass tube,
and is then phosphorescent. It can be re-evaporated.

Its removal deprives the radium of 70 per cent, of its
heating power, and the energy of the emanation is so
great that it is calculated that if a whole cubic centimetre
could be collected in one place it would probably melt the
containing vessel. It is radio-active, and therefore must
be supposed to be in a state of change, like radium.

The transformation of radium into its emanation and
the connection between this change and the radio-active
phenomena which accompany it have been investigated
by Professor Rutherford. The phenomenon, as it appears
to him, occurs in several successive stages. The heavy
atoms — for radium has very heavy atoms — of radium dis-
intregrate, throwing off positively charged particles, whose
masses compare with those of hydrogen atoms, whilst
new forms of matter lighter than radium remain behind,
occluded as it were in the remaining radium. These re-
sidues are also radio-active and undergo further change of
a similar kind stage after stage until at last a, ,if, and 7 rays
are all expelled.

Professor Rutherford suggested on certain grounds that
probably helium would be found among the products of the
disintegration of radium, which led Sir William Ramsay
ind Mr. Soddy to seek it. They find that though the

FiG. 10.— No bag was used in this case Rapid plate. Distance
44 cm. Time of exposure, two hours.

emanation of radium when first liberated by dissolving a
radium salt in water contains no helium, yet this element
may be detected in the same emanation after a few days.
For the present, therefore, we regard helium as the ulti-
mate product of the disintegration of radium, or at least
as the only such product yet detected.

The discovery of radium and of its unique properties
raises some important questions : —

I. — Whence does radium derive its vast supply of
energy ? It has been suggested by some that it acts as
a transformer, picking up energy in some way from its
environment and giving it out again as light, heat. Sec,
in the course of its disintegration. Another school (and
this predominates at present) regards radium as a
form of matter endowed with relatively vast stores of
potential energy ; and it has even been suggested, origi-
nally, I believe, in order to compose certain differences
between the physicists and the geologists on the subject
of the age of the sun, that the energy of the sun would be
accounted for by the presence of no more than three or
four grams of radium in each cubic metre of its substance.
Though, except such evidence as may be derived from
the presence of helium in the sun, we have not much
actual fact to support this latter hypothesis.

One of the latest contributors to this most interesting
problem is Lord Kelvin, who finds the second hypothesis

JlNE, IQ04.T

KX(n\i.]:n(;i' \- sciextific xr.ws.

log

difficult to accept, and pouits out that if two globular
flasks, such as those in figure 12, one containing a
black cloth A and the other a white one B be plunged in
vessels of water and exposed to a source of radiant heat
such as the sun, then the water in the vessel surrounding
A will be hotter than that surrounding 1!, so long as the
experiment is continued ; as may be proved by the
pressure on the mercury at C, or by observing ther-
mometers placed near A and B.

Fig. II. — Time, eight and a half hours. Distance about 7 cm.

Now the suggestion is that radium salts may absorb
energy in this sort of way from some radiation in the sur-
rounding ether, and that we know far too little as yet
about radium and about the wave disturbances in the
ether to dismiss this explanation of the mystery of radium
from consideration before further experiments ha\e been
made.

2. — Is the production of helium from radium " a
transmutation"; does it foreshadow similar transmutations
among the better known and more plentiful elements,
e.g., the transforming of lead into gold or vice versa ?

It is, I fear, impossible to consider the question in this
form seriously till we know much more al)out radium.

On account of its spectrum, the character of its salts,
and their general alliance with the calcium group,
radium ranks as an element. Yet if we are exact we
cannot truly say radium has never been decomposed, for we
explain its most characteristic properties by supposing
that every specimen of radium salt is disintegrating spon-
taneously and resolving itself gradually into other formsof
matter. Hence, it can hardly be regarded as an element
in the sense in which oxygen is considered to be
an element at this moment. The question before us,
therefore, is this — Are the other elements radio-active
like radium and its companions ? Do these also,

though we do not yet recognise the fact, undergo
similar transfornialions, only at a far slower rate ?
If they do, or if we can prove that some of tiie
lighter elements, c.;,'., oxygen, sulphur, or sodium, do so,
then the whole ([uestion of the nature of the elements, the
very basis of chemistry, must come up for revision. At
present the position may be taken, provisionally, to be
something of this kind. The elements may, for the
moment, be di\ided into two classes.

{a) Those which have relatively light atoms, and whicli
are not, so far as we know at present, subject to
disintegration, and are not radio-active, such elements,
for example, as helium, oxygen, sodium.

{!>) Tile radio active forms of matter such as radium,
uranium, thorium, which exist in larger particles and
exhibit many of the characters of the elements, but
which disintegrate, throwing ofiF among their products
atoms of elements of the more familiar type.

Whatever the truth may be, and it seems likely we may
long seek the answer to this big question, it is clear tliat
the study of radio-active matter must greatly enlarge,
iven if it does not re\olutionise, our ideas about the pro-
. esses by which tlu: older and more familiar elements have
iieen generated.

The

Structvire of Crystals.

By H,\i;oi.i) 1 1 11. ton.

It is proposed in this paper to give a brief account of the
modern geometrical theory of crystal structure. The
units of which a homogeneous medium is composed are
called •' molecules " ; they are either chemical molecules

•^

V'Z. 1.

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

or definite aggregates of these. The molecules of such a
medium are either all of the same kind (of the same
size, shape, iSrc.) ; or else they are half of one kind and
half of another, the molecules of the two kinds being re-
lated in the same way as a right-handed and a left-handed
glove, that is, two molecules of different kinds may be
placed so that they are reflections of each other m some
plane. The two kinds of molecules are represented in
the diagrams liy the letters p and q. The molecules of
the medium are arranged according to certain laws of
" symmetry," that is, every molecule of the medium

through a distance t parallel to the axis ; (4) a reflexion
in a plane called a " symmetry-plane " ; (5) a reflexion
in a point called a " centre of symmetry " ; (6) a gliding
reflexion, /.f., a reflexion in a plane (called a "gliding-
plane ") followed by a translation parallel to the
plane ; (7) a rotation through an angle a about a
line followed by a reflexion in a plane perpendicular
to the line. Each of these movements leaves un-
altered the distance between two given molecules ;
they may be considered as equivalent to only two
distinct movements, (i) and (2) being particular cases of

•

/C>

•

Fig. 2.

(supposed of infinite extent in all directions) is brought
by certain so-called "mo\'ements" into the position pre-
viously occupied by some other molecule of the medium
(the medium is said to be " brought to self-coincidence"
by such a movement). These movements are of seven
different kinds:— (i) a translation, i.e., a shifting of each
point of the medium through the same distance in the
same direction ; (2) a rotation through an angle o,
about a straight line called a" rotation-axis" ; (3) a screw,
i.f., a rotation through an angle a, about a straight
line called a " screw-axis " followed by a translation

(3) and (4), (5), and (6) of (7). The movements are
illustrated by figure i in which the molecule i is brought
into the positions now occupied by molecules 2, 4 by
reflexion in the planes B, A (perpendicular to the plane
of the paper) ; and into the position of molecule 3 by a
gliding reflexion in B. The molecule 2 is brought into
the position of molecule 3 by a translation, and of mole-
cule 4 by a rotation through iSo" about the intersection
of A and B. A medium may be brought to self-
coincidence by an indefinite number of different move-
ments, but the presence of certain symmetry-elements

June, 1904.]

KNOWLEDGE c^- SCIENTIFIC NEWS.

1 1 1

(i.f., rouii.. ;; .1^.;^, ... rew-axes, &c.) necessitates or pre-
vents the existence of other elements. For example, if a
medium is brought to self-coincidence by a gliding-
reflexion in a plane, it must be also brought to self-
coincidence by a translation parallel to that plane. It is
assumed that every crystalline medium is brought to
self-coincidence by three very small but linite translations
not lying in the same plane — a fundamental hypotiicsis
which is justified by remembering that the physical
properties of a homogeneous crystalhne medium in a _i;inn
direction are the same in every part of the medium. It
follows from this assumption that the angle a. of move-
ments (2), (3), (7) must be a multiple of 60 ' or of 90". It
may be shown that the number of distinct arrangements
of symmetry-elements is 230 — a geometrical problem
solved independently by Fedorow, Schoenllies, and
Barlow. One such arrangement is shown in figure 2.
The system of molecules there given is supposed extended
indefinitely in the plane of the diagram, and over and
under it at distances 2/,, 4Z, 6z, . . . are placed
similar and similarly situated systems so as to fill all
space. It is evident that tlie collection of molecules so
formed has the lines perpendicular to the plane of the
paper, and passing through the points marked o and 9
as rotation-axes (a = 120"), has the planes parallel t<j
these axes, and passing through any two adjacent points
marked O for symmetry-planes, and has the planes half-
way between these symmetry-planes as gliding-planes.
Such a collection of molecules is one of the six different
geometrically possible ways of representing the structure
of a medium (such as tourmaline, potassium bromate,
&c.), which crystallizes in polyhcdra having a rotation-
axis for which a = 120' and three symmetry- planes
through that axis making angles of Go" with each other
(and having no other symmetryelenient).

Again, suppose that half-way between two neighbour-
ing systems of molecules in the collection just described,
we insert the system obtained by rotating figure 2 through
180^ about one of the points marked O. The collection
has the lines perpendicular to the plane of the diagram,
and passing through the points marked • as rotation
axes for which a = 120°, the lines perpendicular to the
planes of the diagram, and passing through the points
marked O as screw-axes for which a = Go" and t = z,
and the lines half-way between any two adjacent rotation-
axes as screw-axes, for which a = 180' and t = z. The
collection has the same symmetry-planes and gliding-
planes as in the previous case, and has also gliding-planes
through the screw-axes perpendicular to the symmetry-
planes. The collection is one of the four different
geometrically possible ways of representing the structure
of a medium (such as zincite, wurtzite, iodyrite, &c.),
which crystallizes in polyhedra having a rotation-axis
for which a = to' and six symmetry-planes through that
axis making angles of 30'^ with each other.

It must be remembered that it has not been proved
that a collection of molecules, such as has been described,
is one which can exist in stable equilibrium under the
influence of the mutual attractions of the molecules. On
the dynamical theory of crystal structure hardly any work
has yet been done, but the geometrical theory is now
fairly complete.

Gkksham College Lectukes. — A course of lectures on
"Recent Solar Researches" was delivered at Grosham Col-
lege during Whitsun week by Mr. E. Walter Maunder,
F.R.A.S. The subjects of the lectures, delivered on succes-
sive evenings, were " Changes and Movements of Siinspots,"
" The Structure of Sunspots," " The Solar /Vtmosphere," and
" Solar Periods and Influence."

Aeroplane Experiments
at the CrystOLl PoLlaLce.

r>y Major liADiiN-l'oWKLL.

Ir has often bee'ii supposed that one of the greatest
difficulties to be overcome before successful aerial navi-
gation can be achieved is the practical balance of the
apparatus in mid air. Whether or not this will really
prove a stumbling block it is impossible, with our present
experience, to state with irertainty. Several inventors,
it is true, have had considerable dillicultics in the initial
starting of their machines, which have had a way of toppling
over as soon as they ha\e been launched into the air. It
seems just possible, however, that if the machine could

Starting.

be properly trinuned before starting, all such dilhculties
might be overcome. We know that small models, if
dropped from the hand or lightly thrown forward, will
easily upset, if not properly balanced, but which, if the
weights be carefully adjusted beforehand, will fly steadily
enough on their downward course. But it is extremely
difficult to calculate the position of the centres of gravity
and of pressure, and practical trial is the only certain
method of getting this balance, ilow, then, is it possible
to test practically the balance of a machine which we are
loth to launch into mid air because we are afraid of its
toppling over ?

With a parachute or surface dropping perpendicularly,
the weight should, of course, be in the centre of area ;
but if a more or less flat surface be progressing through the
air horizontally, it is found that the centre of pressure ad-
vances towards the front edge, and, therefore, if the weight
be in the centre, the plane will rapidly rise in front, and will
soon overbalance and shoot down backwards, liut the
more rapidly the machine is travelling, the more does the

112

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

centre of effort advance. It would, therefore, seem to be
necessary to shift the balance in accordance with the
speed. The anp;le presented by the aeroplane also causes
this point to vary, so that experiments with the tilting of
the aeroplanes are also necessary.

It is often supposed that, in addition to what we may
call the " passive " or " fixed " balance, we must take into
account the action of the air currents on the wings.
These may be the result both of the eddies caused by the
progression of the planes through still air and of gusts of
wind blowing against them.

These actions and re-actions are little understood.
Some authorities think that a large flying machine will
be blown about like a piece of paper in the breeze, while
others declare that a hea\ y machine progressing at a

principal experimenters in this line have unfortunately
lost their lives through some small deficiency in their
apparatus, and if tried over land there is always the
danger that any small mishap may result in the machine
losing its balance and precipitating its operator to the
ground. Such machines, at all events as hitherto de-
signed, cannot well be tried over water for several obvious
reasons.

Moreover, such apparatus would usually progress com-
paratively slowly. Now, to support itself in the air an
aeroplane must move along at a very considerable speed,
and the questions of balance and of steering are un-
doubtedly much dependent on the rate of progress.

One of the simplest means of giving an initial speed to
any body is to cause it to run down an inclined track

^■l^K-V^^^'^^-itfS&^ii^.. ..-«^I^K:.-

»v5 ^^"

Aeroplane leaving the Track.

speed far greater than that of the wind will scarcely be
affected by it.

Another problem calling for practical solution is that
of steering. Vertical and horizontal rudders may seem
a simple expedient, but it is doubtful if they form the
most efficient means of steering. A bird has no vertical
rudder, and tests with large gliding machines have
pro\ed them to be not entirely satisfactory.

It is therefore manifest that before we can build a
proper airship we must make a series of trials with some
apparatus progressing through the air and carrying an
aeronaut to direct its course. Several experimenters have
tried gliding machines, which have been designed either
to soar down the face of a hill in the teeth of a wind, or
to be drawn along by a string. But in addition to other
drawbacks, these systems have the serious objection of
being very dangerous to the operator. .Mrcady two of the

and to shoot off into the air at the bottom. If means
are adopted to pre\ent the machine from leaving the
track before it gets to the bottom, and if it is then pro-
jected over a sheet of water, there can be but little chance
of a serious accident.

I therefore decided, some months ago, to erect such a
track, and conduct a series of experiments. Existing
" water-chutes " at once suggested themselves as ready-
made tracks, but, after examining several, and even making
experiments with aeroplanes on them, I came to the con-
clusion that such were not suitable to the purpose. They
are not steep enough to get up sufficient speed, they are
not sufficiently turned up at the bottom to shoot the
apparatus off in a horizontal direction, and rails and lamp-
posts interfere with large wings. Besides, it would be
difficult to arrange any method by which the aeroplane
could be prevented from rising off the track before

June, 1004 1

KXOWI.l'.DCI' \- SCll'XTIl'IC Nl'WS.

113

c
c

O
u
di

114

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

arriving at the bottom, which it is very apt to do in
gusty weather.

By the courtesy of the Mana<:;ement of the Crystal
Palace, the magnificent grounds of that institution have
been placed at my disposal, and a most suitable spot was
soon found beside the Intermediate Lake. Mere I have
had a larsje staging erected, of which the accompanying
photographs will give a good idea.

Mr. C. J. Pilomfield, the well-known architect, very
kindly undertook to superintend the details of construc-
tion. This staging is of wood, the upper end beinj,' some
30 feet abo\-e the level of the lake. '1 he incline is one in
two, the lower end forming a curve of '10 feet radius.
The "take off" is on an upward incline of one in ten,
the lowest portion of the track beint; about ten feet from
the outer end, which is six feet above the water level.

The rails are composed of solid slabs of oak securely
bolted lo the structure, and projected inwards so as to
allow of runners enijaging on their under sides as well as
on the upper. They have a gauge of 2 ft. f> in. These
are carefully smoothed and greased to minimise friction.
The flying apparatus consists of a boat, flat-bottomed,
and with a considerably rockered stem, about 20 feet
long over all, by 2 ft. 6 in. beam. From the sides of this
project runners of oak to slide on the rails, and also some
projections which are to engage the under sides of the
rails in the event of the wind lifting the wings on one
side, and thus prevent the machine being overturned or
lifted upwards off the track.

The rate of descent is found to be 50 feet per second
near the bottom, but this speed is, of course, diminished
slightly during the upward incline before the boat leaves
the track. An electric chronograph is to be fitted so that
the speed can be measured over various sections of the
track. The track is only just completed, and the proper
man-carrying boat is still in hand.

The photographs show a skeleton pattern boat which
was constructed to better get at the most suitable
dimensions and shape. This, as may be seen, was
fitted with two rectangular aeroplanes, each 12 feet by
5 ft. 6 ins., so that the area of this model is 132 square
feet. Later on it is proposed to apply other shapes and
forms of aeroplane to compare various patterns, and tails
of different designs will also be tried.

I propose shortly to start making regular trials and
shall hope to be able to give full accounts of these in the
next number of " Knowledge & Scientific News."

Mr. J. Semenoy (see Journal dc Physique, Feb., 1904) causes
electric sparks to jump between two gas flames or a flame and
a metallic electrode, or else between two metallic electrodes
separated by a small gas flame. By this arrangement the
glow is eliminated, so as to enable the spark proper to be
examined separately. In fact the metallic vapours constituting
the glow are blown aw.ay by the gas stream of the flame.
The image of the spark is projected by means of a con-
vergent lense on the vertical slit of a direct-vision spectro-
scope, the axis of which is perpendicular to the plane of the
spark gap.

Semenov's experiments go to show that dirtric currents in
gases are a molecular phenomenon ; this would be in accord with
Professor Bouty's researches on the dielectric cohesion of
gases, which is also a molecular property.

Such currents are attended l>y the dissociation and projec-
tion of matter, the paths of which are in each point of the
spark orientated in a plane perpendicular to the line of current.
On account of the projection of matter taking place round the
spark, a vacuum must be produced along the spark, the
atmospheric pressure throwing into this vacuum the air and
metallic vapour surrounding the electrode ; this is obviously
one of the causes of the transport of matter taking place from
one pole to the other. — A. G.

The Development of
Parasitism.

r.y J. Re'ixolos Grei:n, Sc.H., I'.K.S.

The early ancestors of all plants now existing are
generally held to have been aquatic organisms of fairly
simple type, and of not very complex structure. Without
going back to the extremely simple protoplasmic entity,
whose nature cannot be said with certainty to have been
vegetable rather than animal, we must admit the exis-
tence of a I'ace of plants, each of which was capable
of living for and by itself, of carrying on all the functions
of nutrition, and of reproducing itself. The power of
nourishing itself involved a further power; it must have
been able, under the infiuence of the rays of the sun, to
construct or.Ljanic food material from the inorganic simple
compounds furnished to it by its enviromnent. The
possession of this power was one of the earliest acquired
marks of distinction between the animal and vegetable
organisms, for though traces of it may be found in the
former, they are but traces ; and it is uncertain how far
they actually pertain to the animal world. The vege-
table organisms on the other hand, bavin"; once acquired
the power, have retained and developed it till it is now
recognised as their special and distinctive feature.

This peculiar property of constructing organic material
from inorganic, on which all physical life depends, is
associated with the presence in the vegetable organism
of a peculiar green colourin,<i matter, known as chloro-
phyll. The pigment is in nearly all cases found associated
with peculiar differentiated portions of the living sub-
stance, known as plastids, which, though commonly small
ovoid bodies lying in the general protoplasm of the
organisms, may in the more lowly forms assume curious
shapes. The power of food construction from inorganic
materials and the presence of these chUiraplasiids go
together, and the possession of what is often called
this chlorophyll apparatus is the distinguishing feature of
most plants.

Endowed with this apparatus, exposed to the rays of
the sun, supplied with such simple inorganic substances
as the carbon dioxide of the air, the water and the
nitrates, sulpliates, and phosphates of the soil, the plant
can fight its own battles and reproduce its race.

In studying the vast field of vegetation that the face
of the earth presents us with, however, we come across
many types which are not nourished in this way, which
have no power of food-construction, and which can only
live, animal fashion, on organic materials ready made for
them.

Looking more closely into the habits of such plants,
we can distinguish between two classes of them, one
thriving on dead, decaying organic matter, the other
preying upon living organisms.

The latter form the great group of parasites, a degraded
class which thrives by robbing other organisms of the
food they fiave acquired, and by taking from them
their own vital fluids, causing malnutrition and death.

The study of parasitism as seen in the \egetable king-
dom illustrates very fully the law which is so well
illustrated in the processes of the evolution of the races
of both animals and plants, that disuse is followed by
atrophy. Whether the parasitic plant lives at the ex-
pense of another plant or whether it attacks an animal
organism, the result is the same — the disappearance of its

Jl-NE. 1904.]

KNOWLEDGE c^ vSCIENTIEIC NEWS.

115

chlorophyll appai.iUi>. the loss of the power of food-
construction, and a consequent degradation of structure,
always found accompanying such impotence.

The development of the parasitic habit has not taken
place among one group of plants alone, and the parasitic
plants are not therefore connected with one another by
any ties of descent or inheritance. Parasitism has been
acquired by simple and by complex plants, and ap-
parently more than one chain of circumstances has k^d up
to it.

Among the simpler families wc find the great class of
bacteria, or germs, in many cases parasitic, liiough others
live on dead organic matter. Such as the latter are
designated sapropliytis, and in many cases they mark a
halfway house to parasitism. A group of somewhat
higher type is aflorded by the fungi or moulds, which, like
the former, include both saproph3tic and parasitic
forms.

From their structure these parasitic fungi are closely
allied to the filamentous alga- or sea-weeds, from whicli
it is clear that they have been deri\ed. There are many
families of these aquatic organisms, distinguished from
each other by their peculiar methods of reproduction.
There are corresponding groups of fungi, and from com-
parison of them there can be little doubt that the fungi
have been developed from the alga^ which they resemble.

The process of their development, though based upon
existing forms of both, can be fairly satisfactorily traced.
We have, however, only prohability to point to, for we have
not very satisfactory transitional forms. The main differ-
ence between the two is the presence of the chlorophyll
apparatus in the one and its absence from the other. This
involves, however, a change of habit of life which has led
to modification of the structure of the plant body.

It is not very difficult to see how the parasitic habit
probably arose in these lowly plants. Their bodies are
not differentiated into definite members like the higher
plants, but arelitile microscopic spheres or flat plates,
or filaments. Many of them now are found to be
living in a soit of association with each other, not help-
ing each other further than by supplying mechanical sup-
port. If we imagine a comparatively large form support-
ing a number of smaller ones, we can see that its death
and decay would present to those adhering to it a con-
siderable amount of organic material ready for consump-
tion. Such a source of food supply may well ha\e been
utilised, for its absorption would relieve the adhering
plants from much labour of construction. A saprophytic
habit thus assumed would be likely to be permanent,
and the manufacture of the now unnecessary chlorophyll
apparatus would gradually die out.

The forms thus acquiring saprophytism have betn many
and varied in their form. The great majority have
been filamentous, consisting of long threads known as
hyphd . These threads permeate the mass of the decaying
organic matter. Such are many of our common moulds,
which are developed now so easily upon syruppy sub-
stances.

The passage from this comparatively harmless way of
getting food to the destructive form of parasitism is not
very difficult We can trace it in many of the fungi
which are at our side today. Instead of waiting for the
death of the plant to which the fungus is attached, the
latter in many cases kills it by secreting and pouring out
a toxic substance or poison which causes a local death of
the tissue with which it comes into contact. Into this
dead nidus the filaments of the intruder then grow, and
so its establishment takes place in the interior of its host,
such growth being preceded by a destruction of the latter,
the materials so formed being the food of the fungus.

This conduct marks a stage very near to the establish-
ment of the true parasitism, which involves only the feed-
ing of the intruder on the materials of the host plant,
prior to death and decomposition. This change of nutri-
tive method soon follows, the intruder gaining the power
to assimilate the juices of its host without any such de-
composition. Then the gradual weakening of the host is
the sign of the in\-adi,'r, which has ceased to manufacture
the toxin or poison which was at one period a necessary
phase in the process of the nutrition.

We cannot point to organisms which are at present in
the early stages of this transformation of nutritive pro-
cesses, but certain fungi can be found which have hardly
passed beyond that of the loss of the chlorophyll appa-
ratus. One which is known as Pythiitm attacks young
lettuce seedlings, causing the disease known as dniiipinf^
of. This illustrates the change ; it has no green colour,
and gains all its food from the lix'ing tissue of the seed-
lings, but its structure, and especially its modes of repro-
duction, are strikingly lik'e those of the alga? to which it
is related. The reproducti\e cells which it forms, their
shape, and structure, the mode of their formation, andlheir
general behaviour are strikingly algal. Among the
various species of the genus we find forms whicli are
gradually losing these algal peculiarities, andare beginning
to show the degradation of structure which always is
associated sooner or later withthe parasitic mode of life.

Besides these pathogenic forms, bacterial and fungal,
associated emphatically with a diseased condition of the
host plant. Nature shows us others which are much
higher in the scale of organisation, belonging iiuleed to
the highly organised flowering plants. When we pass
in review a series of these parasites we find the same
succession of events, the acquirement of parasitism ac-
companied by a loss of the power of constructing organic
substance and a progressive degradation of the whole
organism.

In tracing the development of the habit among these
higher plants we find suggestions that it originated in a
different way from that which we have noticed among
the fungi. Saprophytism is not unknown among the
flowering plants, but it has apparently had no part in the
development of parasitism. The origin of the latter
must be looked for in the close relationship often found
existingamong plants which were originally nothing more
than neighbours, by virtue of which they came to help one
another in a peculiar manner in the struggle for existence.
This relationship, known as symbiosis, is a union of two
plants for their mutual benefit. It is seen in many cases,
conspicuous among which we have the lichens, peculiar
organisms consisting of an alga and a fungus living in
close relationship with each other, each contributing a
share to the well-being of the compound organism.

The origin of such symbiosis among the higher plants
can be seen in the case of a group of plants often known as
roolparasilcs. They include many members of the Natural
(_)i(ler ScrophuliU'iiKr, e.g., the yellow-rattle which grow
in pastures and waste ground. The roots of these plants
are growing freely among the roots of the other plants,
the grasses, &c., of the pasture. Coming into contact
with these, the irritation of the contact causes a swelling
to arise upon the root of the rattle, and from this growth
delicate filaments emerge which penetrate the grass root
and set up an intimate relationship between the two,
which become so far united that liquid matter can pass
with comparative ease from the one to the other. The
relationship so set up is not particularly harmful to the
grass ; indeed, it seems to be beneficial to both symbionts,
bringing about in a way an eijualisation of the nutritive
material that both are engaged in making. It involves

ii6

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

no diminution oi i.ic < ulorophyll of either, and no degra-
dation of structure.

.\ further stage in the acquiremeni of tlie parasitic
rather than the symbiotic habit is exhibited by the mistle-
toe and its allies. We are most of us familiar with the
mistletoe, an evergreen plant with pale greyish-green
lea\es, found growing on the poplar, apple, uVc. It arises
in all cases from the germination of seeds deposited by
buds in the bark of the branches of the host. The young
rootlet of the mistletoe inserts itself into the bark, and
penetrates the soft tissues of the cortex as far as the j-oung
wood. Subsequent growth and development, which are
accompanied by the co-incident grow-th and increased
thickness of the branch, lead to the establishment of a very
close union between the tissues of the two, and as the
plumule of the seed develops and the upper portion of the
mistletoe plant increases, the two are so firmly joined that
the organic food of the host is easily absorbed by the
intruder. The relationship is still symbiotic, for while
during the greater part of the year the host plant feeds
the mistletoe in preponderating measure, in the winter,
after the leaf-fall of the host, the evergreen guest contri-
butes to the nutrition of both. The plant shows, however,
the beginning of the inequality of symbiotic eflfort which
is the antecedent of parasitism. Co-incident with this w'e
find the beginning of the degradation of the chlorophyll
apparatus, the mistletoe possessing leaves of very grey-
green colour.

The inequality thus established can be traced a stage
further in the genus Orohaiichc, the so-called broom -rapes,
which are far from uncommon among our wild plants.
They consist of a large fleshy stem ending in a spike of
flowers ; the stem bears a few almost rudimentary
leaves which are almost brown, having but little green
matter in them. The broom-rape is found seated upon
the roots of some other herbaceous plant, and is furnished
with a greatly thickened and swollen base by which the
attachment is made. The swelling is cfue to the absorp-
tion of nutritive matter from the host plant, which is now
almost the only source of food possessed by the intruder.
Parasitism is practically established; the chlorophyll
apparatus of the broom-rape is rudimentary and abortive,
and the burden of feeding both falls upon the host plant
which suffers in consequence.

The common Dodder shows as yet another stage. The
plant infests many herbaceous plants, especially clover.
The seed germinates on the ground, and the young embryo
twines itself around some neighbouring stem. Having
established its hold, it forsakes the ground, and in all its
subsequent growth it twines more and more fully round
its host. The long twining stem bears no leaves, and
contains no chlorophyll. At intervals along its course it
puts out sucking root-like filaments, which perforate the
host and set up a close union between the tissues of the
two. So fed, the Dodder flowers and seeds, altogether at
the expense of its host.

Our own flora shows us no more complete instance of
a parasite than this. In some tropical areas a parasite
can be met with which lives entirely wrapped up inside
the tissues of its host. The degradation of its structure
is complete, for its anatomical complexity is reduced to a
very close resemblance to the hyphal network of a fungus.
I lere and there an outgrowth of the plant penetrates the
surface of the host plant, and develops into a flower,
which in some cases has an enormous fleshy body. The
parasitic habit now dominates the plant ; it lives only to
produce its flower, it has lost all trace of normal struc-
ture, it obtains everything from the internal tissues of its
host, and stands before us indolent, atrophied, and yet
triumphant.

The AvitobiograpKy of
Herbert Spencer.

The late Mr. Herbert Spencer has written his " Auto-
biographj- " (Williams and Norgate) in a vein of exceeding
seriousness. Other men who have written their autobiogra-
phies endear themselves to their readers by their unconscious
revelation of character, even their human weaknesses. Mr.
Herbert Spencer had no human weaknesses ; he appears in his
autobiography as the personification of abstract thought. It
is true that he was a dutiful son; indeed, in speaking of his
mother, he approaches more nearly to tenderness than on any
other occasion, but even here he displays that detached clear-
sightedness that characterises all his relations in life. •• Of
my mother's intellect there is nothing special to be remarked,"
he comments, and adds with that one touch of feeling already
mentioned. " speaking broadly, the world may be divided into
those who deserve little and get much, and those who desene
much and get little. My mother belonged to the latter class :
and it is a source of unceasing regret with me that I did not
do more to prevent her inclusion in this class." The reader is
feign to share her son"s retrospective sympathy for Mrs.
Spencer when he learns something of her husband's irritating
characteristics. " He held, for instance, that everyone should
speak clearly, and that those who did not ought to suffer the re-
sulting evil. Hence, if he did not understand some question
mv mother put, he would remain silent ; not asking what the
([uestion was, and letting it go unanswered. He continued
this habit all through life, notwithstanding its futility. " Mr.
Spencer arraigns his earlier Huguenot and Wesleyan pro-
genitor? in the same scientific spirit, tracing in his own
character kindred traits derived from them. " That the spirit
of Nonconformity is shown by me in various directions, no one
can deny, " he says in conclusion. ■' The disregard of authority,
political, religious, or social, is very conspicuous. Along with
this there goes, in a transfigured form, a placing of principles
having superhuman origins above rules having human origins,
for throughout all writings of mine relating to the affairs of men.
it is contended that ethical injunctions stand above legal in-
junctions."

The elder Mr. Spencer postponed his son's education on
grounds of health ; but, desulton,- as it was, at thirteen he bad
acquired considerably more general knowledge than is com-
mon at that age. Of Latin and Greek, he knew '• nothing
worth mentioning." Of English grammar or history, he was
entirely ignorant, and the deficiency in bis literary education
makes itself felt in the roughness of his English; but, on the
other hand, " my conceptions of physical principles and pro-
perties had considerable clearness, and I had a fair acquaint-
ance with sundry special phenomena in physics and chemistry,"
.\ far more important mental acquisition, and one in which
school education is conspicuously deficient, was what Mr,
Spencer describes as the habit "of intellectual self-help,"
which his father was continually inculcating. Shortly after he
was thirteen Herbert Spencer went to continue his education
at the house of an uncle, where be seems to have derived more
benefit from mental and moral discipline than the actual ac-
quisition of knowledge. Soon after his return home he entered
on a brief career as a teacher, his father's profession. In 1S57
he obtained a post under Mr. Charles Fox, Permanent Re-
sident Engineer of the London division of the London and
P)irmingham Railway during its process of construction.

" I arrived in" London on the Sth November, 1S37. . . .
The Queen, who had but lately succeeded to the throne, and was
not yet crowned, dined with the Lord Mayor in the City on the
qth of November, and the occasion called for a State Pageant.
It was the only Royal procession or display of allied kind
which I ever saw. " He adds later: '• I was quite alive to the
responsibihties of my post and resolute to succeed. During

JlNE, 1904.]

KNOWLEDGH \- SCII-NTIFIC NEWS.

117

the whole of my sojourn hi London, lasting over six nioiiths, 1
nevor went to a place of anuisement ; nor ever road a no\ el or
other work of light literature." It was surely this ituapacity
for healthy recreation, ingrained l>y his education, that was
largely respousilile for the ill-health .tnd nervous strain w ,th
which Herbert Spencer had to coiiteud during his later years.
t)ne cannot read without a smile his grave aniul.ldv^■r^iolls on
the eoenpanions with whom he was thrown at tlie ( iigiiuering
oflicesat Worcester, to which he subsequeutly went. " I'nlike
the pupils of Mr. Charles Fo.\, quiet youths, carefully In ought up
(two of them being sons of dissenting iniiiisteisl. the junior
members of the Birmingham and Gloucester stalV belonged
largely to the ruling classes, and had corresponding notions
and habits." . . . "The superintendence was not rigid.
and the making of designs was intei perseil now with stoi lis not
of an improving kind, now with glances down on the pas.sers
by, especially the females, and resulting remarks; there being
also a continuous acconipaninient of whistling and singing,
chiefly of sentimental ballads." .\mong these young men
Herbert Spencer was, however, able to form one coiigtnial
intimacy, which we remark upon becau.se it instances .igain
that detached ijuality ofmindaUeady mentioned, tli.it liabil ot
appraising his fellows, even his most intimate fiiends. " lie
was the son of Dr. Jackson, at that time foreign Secret. iry to
the Bible Society. Of somewhat in)gainly build, and with an
intellect mechanically receptive, but without much thinking
power, my friend was extremely conscientious. ' . . . ".As
sociation with a man whose intellectual powers weie above niv
own would have been more advantageous," he adds.

.About this period. Herbert Spencer notes that religious
belefs were slowly losing their hold, "the creed of Christen-
dom being evidently alien to my nature, both emotional .iiid
iutellectiial." "Criticism," he coiitinnts, " liad not yet shown
me how astonishing is tlie supposition that the Cause liiim
which have arisen thirty millions of .Suns, with their attendant
planets, took the form of a man, and made a bargain with
.Abraham to give him territory in return for Allegiance." " I
had not at that time." he continues, " repudiated the notion
of a deity who is pleased with the singing of his praises, and
angry with the infinitesimal beings he has in.ide when they
fail to tell him perpetually of his greatness." an extraordinary
crudeness of statement " of the Creed of Christendom," wliich
can only be accounted for by Herbert Spencer's Noiu on-
formist antecedents.

In 1S41, Herbert Spencer returned home, partly to i)insue
a course of mathematical study, and jjirtly to carry out his
father's idea of an electro-magnetic engine. Neither scheme
was pursued. It is curious to find him continually comment-
ing on his "constitutional idleness," which "has t.iken the
form of inability to persevere in labour which has not .in
object at once large and distinct." The years that followed,
though they were apparently desultory and futile iroin the
point of view of material advancement, were of crucial im-
portance in the history of Spencer's subsequent career, .uid
in determining the bent of his genius. He instances, as a stc p
in his mental development, the letters on social ipieslions
contributed by him to the Xoiicuiijoniiist, an organ of th(-
Advanced Dissenters, letters which originated in political
discussions with an uncle, who introduced liini to the editor : —
" Had they never been written. Social Statics, which
originated from them, would not even have been thought
of. Had there been no Social Statics, those lints of
enquiry which led to 'The Principles of Psychology'
would have remained unexplored. .And without that
study of life in general, initiated by the wiiting of these
works, leading presently to the study ot the relations
between its phenomena and those of the inorganic
world, there would have been no System of Synthetic
Philosophy.''
Meanwhile, he was besides variously occupi d journalisti-
cally and otherwise, and in 1S50 appear(;d his first book,
" Social Statics ; orlhe Conditions Essential to lliiman Happi-
ness Specified." "Assuming happiness as the end to l)e
achieved, it regarded achievement of it as dependent on
fulfilment of conditions, conformity to which constitutes
morality."

After the appearance in 1S55 of his second book " The Prin-
ciples of Psychology," he suffered from a serious breakdown
in health which enforced a long period of idleness. To these
two books Mr. Spencer appends with characteristic aloofness

of mind two hypothetical reviews, criticising his own .ugu
mcnts .iiul suinmaiising his doctrims. .-Xs soon as his he;illh
w.is sullicii'iitly recovered, he set to woik upon his " .System ol
Synthetic Philosophy." He describes himself at this time as
"a nervous inv.did " " h.iving only iirecarious resources," and
his undertaking, so inonuinental .a task, necessitated ;i heroic
struggle with physical weakness. Aftii the public. ition of the
first e.irly part of the work he found hiinseU obliged to decide
upon the abaiulonmtnl of his design. His parents wer(^ in
need of his support, and he had already trenched considerably
upon his small capital. The proposal iinniediatelv called
forth the following generous response fioin J. S. Mill:

" It is right that you should be indeinnilied by the readers
and puicha.sers of the series for the loss you have inciured l>y
it. 1 should be glad to contribute my part, and should like to
know at how niucli yon estimate the loss, and wlu-tlu-r you
will allow me to speak of it to Iriends.uid obl.iin ^>ubscriptions
lor the remainder."

The propos.il was (■ventually declined. The de.ith of the
elder Spencer lessi^ned his son's responsibilities, and .American
.admirers placed 7000 dollars to his credit in public securities.
01 Herbert Spencer's rel.itions with his contemporaries we
have hardly space to jpeak. One instance must hulTue ol the
shrewd but inercilets clear-sightediu ss with which lie esli
mated the mental .and moral calibre of his ac(|uaintances. ( )f
Cailyle lit- .says: " He has, strange to say, been elas.sed as a
philosopher! Considering that he either could not or would
not think coherently — never set out from premises ;inil
reasoned his way to conclusions, but hal>itually ihalt in intui-
tions and dogmatic as.sertions, he lacked the trait which, perhaps
more than anv other, distinguishes the philosopher properly so
called. He Licked :ilso a further trait. Instead of thinking
calmly, as the philosopher above all others does, he thought
in ;i |)assion. It would take much seeking to'find one whose
intellect was perturbed by emotion in the same degree."

Photography,

Pvire a-rvd Applied.

]jy ClIAIMAN JnxKS, I'.I.C, I'.C.S.

In introduciii.L,' the first of the Photographic sections to
the readers of " Know 1 1 ik.i ," it is lit that I shoulil s:iy
soniethin;^ as to llu- geiitial character of the matter that
they may i xpcct to liiul in this part of the jomiial.
li\ci)oiie may now lie considered to lake a practical
interest in photography, just as everyone knows how to
write his own language intelligibly. Therefore it will be
my endea\oiir to deal with matters connected with the
practice of tlu- ait :is ojjpoi tunity seems suitable. A few
perhaps lake an iiiteresl in photography for its own sake;
and as the pure science of to day may be regarded as the
ap|)lied science of tomorrow, I shall hope to draw the
attention of readers to notable items of progress in photo-
graphy, even though their immediate application may
not be very obvious. Hut in all cases it will be my
endeavour as far as possible to meet the needs of all who
take the trouble to read these notes, and to enable me to
do this 1 shall welcome any suggestions or questions of
general interest, anil the account of any photographic
experiences, whether in connection with scienlilic work
or the general practice of the art.

'I'lic Rcmicriii'^ of Colony. — It is a notable sign of the
times that the only films now made by the Kodak Com-
pany are colour sensitised or isochromatic. .Although

ii8

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

colour-sensitised plates have been available for many
years, and in photo-micrography and other scientific work
they have long been considered as indispensable, even
those who know the advantages that they offer too often
appear to lose their critical sense as soon as they take
their cameras out of doors. It is a mistake to suppose
that the proper rendering of variously-coloured objects is
an artistic matter; it belongs to the realm of science, and
the reason that it is neglected is that we have got so used
to the conventional errors in the representation of coloured
objects in monochrome by photography that they do not
offend the eye as errors in outline do. Another reason
is, I think, that it has so often been represented of some
colour-sensitised plates that they do not need a coloured
screen, that many who have seen the results of their use
without that assistance have been unable to find any
advantage in them. There is no available colour-sensi-
tised plate that will give an advantage worth having
in ordinary work by daylight, even if detectable by
critical examination, unless it is used in conjunction with a
coloured screen. The sensitiveness to blue light is so
overpoweringly great that the little added sensitiveness
to green, yellow, or red is lost unless the blue light is
reduced. And the deeper the colour of the screen the
more correct will the resulting photograph be so far as
the use of well-known commercial screens (or light filters
as some call them) is concerned. By the injudicious use
of dyes it is easily possible to absorb so much blue that
this colour photographs as if it were black, while yellow
and green will appear as if white. It is safest not to use
a screen that requires the exposure increasing to more
than about eight times, unless one has some guarantee
that it is suitable. At about this stage, and beyond it, it
becomes necessary to adjust the screen to the particular
plate that is to be used. It is a mistake to suppose that
a coloured screen renders exposures outrageously long.
The screen that probably requires a greater increase of
exposure than any other on the market, the "Absolutus "
screen made by Messrs. Sanger Shepherd, and Co. to
suit Cadett's spectrum plates, and it requires exposures
out of doors to be increased about forty times, as a rule
only needs the giving of a few seconds' exposure instead
of a fraction of a second. For hand-camera work, it is
well to have a screen that needs the exposure to be
doubled, and also one that requires it to be increased to
four times or more for use when circumstances permit.
It is well worth the little extra trouble involved if only
tor the sake of the improvement that will be manifest in
the skies, especially when these are partly or wholly
cloudless.

Catatypc. — This interesting process seems to be still in
the dcnibtful stage so far as its practical uses are concerned.
It was patented nearly three years ago by Messrs. Ostwald
and Cirus, and is one of the results of Professor Ostwald's
investigations in connection with catalysis. Finely
divided metallic platinum or siKer causes the decomposi-
tion of hydrogen peroxide when merely brought into con-
tact with it. If, therefore, a photograph in which the
image consists of metallic silver or platinum is flooded
with a solution of peroxide of hydrogen in ether, when
the ether has evaporated the peroxide will be decomposed
where it is in contact with the finely divided metal, and
if the original is a negative there will be on it an invisible
positive image in hydrogen peroxide. By pressing such
a treated photograph against a gelatine film for about
thirty seconds, a notable quantity of the peroxide will be
absorbed by the gelatine, and such a " print " can be de-
veloped, or made to give a visible result in many ways.
An alkaline siher solution will give a black image of
metallic silver, an alkaline lead solution a brown image

of lead peroxide, and so on. By treating such a print
with a f( rrous salt, the peroxide will convert the ferrous
salt inti a ferric salt and this will render the gelatine
insoluble in water. If the gelatine has been mixed with
a pigment, as in ordinary carbon tissue, and the print is
developed by means of warm water as an ordinary carbon
print is developed, it is stated that this method of pro-
ducing carbon prints gives the print ready for develop-
ment in about two minutes instead of the time usually
required to sensitise the tissue with bichromate, dry it,
and expose it behind the negative. The process may
also be available for photo-mechanical work, for it is
stated that gelatine that has absorbed peroxide of hydrogen
will take up a fatty ink after the manner of chromated
gelatine that has been exposed to light. It is to be hoped
that we shall soon hear more of the practical applications
of these methods.

(To he continued.)

The Antiquity of the
Constellations.

Tl) THE EdITOUS of " KNOWLEDGE."

Gentlemen, — Let us hope that Mr. Maunder may tell us
more about the origin of the constellations. The late Mr.
Proctor was very bold and fixed the date at which they were
invented (or revealed) at 2170 B.C., neither more nor less. Mr.
Robert Brown, too, one would gather, was given (liUe Balbus)
to rashness in speculation.

Mr. Maunder puts the approximate date at 2800 b.c. But
some difficulties suggest themselves on the brief summary of
his arguments, f./,'. : —

(i) The centre of the space not included in the ancient
constellations must have been the S. pole of the period
when they were designed.

But do we Unow all the ancient constellations ? A recent
w-orli, " Sphacra " (referred to below), gives, not 48, but some
150. Many are duplicates (and the variants are curious and
interesting). Others are quite unidentified, i'.,^'., the market
place, the two skulls, tlie stag with two snakes in his nostrils.

(2) The tradition of the four royal stars marking the

colures.
But Rcgulus was a " royal " star for an obvious astrological
reason. It was the heart of the royal beast, the lion, and was
supposed to rule the fates of kings. (The star called Cor
Hydrae, or the serpent's heart, denotes trouble through
women.) If t!ie Persians called other stars "royal" they
may have liad ecpially good (or bad) reasons of the kind.

(3) The date gives the only symmetrical position for the

actual constellations of the Zodiac.
But then- is a strong tradition that they were originally
eleven, nut twelve, and their position otherwise is far In mi
symmetrical.

(4 1 The ascending signs at this date laced east ; the
descending west.
But why did three face nowhere iu particular ? Manilius
gives amusing explanations.

(5) There arc traditions of Taurus leading the Zodiac.
Possibly, l)ut the familiar lines of Vergil in the first Georgic
do not prove this.

It is not safe to base arguments on poetry, and, iu fact,
Seneca finds fault with the agriculture of this very passage
(Ep. 86): "()nr Virgil considered effect more than truth and
wished to please his readers, not to teach farming." But the
astronomy is right enough. Virgil is thinking of .'\pril, and
Ovid's lines (Fast IV. 88) arc the best explanation ; —
Nam. quia ver aferil tunc omnia, densaijue cedit

Frigoris asperitas, fetaque terra patet ;
Aprilem memorant ab aperto tempore dictum.

When that Aprillt with his showrts soote
Tlie drought of March had perced to the roote.

Jlne, 1904.]

KNOWLEDGE lS: SCIENTIFIC NEWS.

119

AccordiDg to ColunK'll.i the sun enters Taurus on April 17,
and the dog sets with the sun on the last day of the numth.

My principal object in writins; this letter is to call attention
to the German book {" Sphaera," by Fran/ Boll, Leipzig ;
Teubner. 1903) above referred to, which gives new Greek
texts, and sheds a flood of li.ght on the history of the constella-
tion signs.

The new texts arc astrological, and indicate a promising
field of investigation.

One vexed problem which is incidentally solved is that of
the so-called Zodiacs of Dendera, which, though neither
Zodiacs nor pictures of the heavens at any date, arc shown to
be of capital importance in a new direction.
I am. Gentlemen.

Your obedient Serv.ant,

T. K. AnNOLD.

23. West Side, Wimbledon,
Feb. iS, 1904.

[Mr. Arnold has not quite understood the significance of Dr.
Franz Boll's valuable work. The new Greek texts discovered
and discussed by him have no direct bearing on the origin and
antiquity of the constellations. They were found in late
mediaeval manuscripts and consisted of excerpts from astro-
logical writers of the first to (he fifth centuries of our era.
The chief interest attaches to the discovery of some texts of
the writings of the Babylonian astrologer Teucros ; perhaps
better known to P'nglish readers as Zeuchrus, who lived about
the Christian era or in the first century a.d. Mr. .Vrnold has
apparently been misled by Dr. Boll's use of the word " sterii-
bildcr." The additional constellations of which Mr. Arnold
speaks are mostlv not " constellations " at all in the sense in
which we ordinarily use that word, i.e., groups of actual stars,
but are simply decanal symbols. The •• decans," or portions of
the ecliptic ten decrees in length — th^(^e therefore to each sign
of the Zodiac — go back to a great antiquity, but are necess.Trily
of much later date than the original ma])|>iug out of the constel-
lations. For the actual constellations are most irregular in
length, and the division into decans implies that the ecliptic had
been previously divided into twelve equal parts, bearing
only a rough relationship to the constellations and not
corresponding to the actual stars, though the new " Signs "
naturally took their names from the old " Constellations."
The symbols attached to the 36 decans are therefore not
truly stellar at all ; they partly look back to the Egyptian
system of placing the year under the protection of 36 deities,
partly to the association of each of the twelve zodiacal
constellations with its " paranatellont;i " or extra-zodiacal
constellations, and p.artly to the desire of the astrologers to
have a fuller supply of prognostics to work with than the
twelve signs .ilone could give. Thus the " Agorii," or Market
Place, mentioned by Mr. .\rnold, was in tlu' second decau of
Libra; and was clearly lint an enlargement of the idea sug
gested by the Balances, of buying, selling, and weighing.
It is not a question of an actual star group bearing
that name. It simply indicated the middle ten degrees of
longitude of the •' Sign " Libra. The •' two skulls " are neither
new nor unidentified. Dr. Boll himself points out that they
are mentioned Ijy Albnmasar, one of the best known of
mediieval astrologers of the Ninth Cintmy a.o. They are
placed, usually with other symbols, in tin- third dee.in of
Libra, and quite possibly are nothing but a very coniipt form
of the " He.ivenly Twins," Adonis and Aphrodite, Tannrmz
and Istar, /.I-., the Sun and Moon. 'I'here is no reason for sur-
prise that so much variation is found in the symbols attached
to the decans and their sub-divisions. They never had the
authority, for they had not the antiquity, of the consti'Ilations,
and many, no doubt, owed their origin to the caprice of indi-
vidual astrologers, or to an imperfect understanding of symbols
employed in foreign systems. Dr. Boll's work supplies some
interesting cases of the wide differences shown in m.iimscripts
professedly based upon the same original authority.

.^s to another point raised by Mr. Arnold, the conslellaticins
of the Zodiac, so far as we can trace them with cert.unty,
were always accounted twelve, even if only eleven separate
figures were shown. The Scorpion had a double portion
allotted to him in schemes which did not display the B.ilance ;
sometimes, as in tlx^fireek sclu-me, his claws extended to the
feet of Virgo; sometimes a second scorpion took the place nosv
held by the_Balance. But it will be noted that Libra is recog-

nised by the astrological scheme ; so lliat whenever tin: B.il-
ance was introduced it nnisl liave been before the working out
of systematic astrology, and befoietlu- division of the "signs"
into '■ decans."

Mr. Arnold's explanation of the name of Kegulus does not
lead us far. It leaves unexplained why a lion was designed in
that part of the sky. But if Kegulus got its name of •' King "
wlien it marked actually the higlic-st point of the ecliptic, on
account of its pre-eminent position, it would not be very
mmatural that the form of the ■• King of Beasts" should be
figured out round it. The Southern l''ish and the Scorpion
.are certainly not ''royal" beasts at .ill: the Hull ([ueslion.ibly
one ; so that no astrological reason is likely to have gained
that title for l^omalhaut, Antares, and .'\ldebaran. But their
relation to the other cohues being so simil.ir to that which
Kegulus held to the colure of the sunmier solstice may well
have caused thetitle to be extended to them ; especially astlie
date indicated agrees so will with (h.it suggested by the un-
mapped space in the south.

I'he three signs which face nowhere in particul;u' are Libra,
which had no face to turn, and Pi-sces and (iemini, which had
each two, looking in opposite dii'cctions. DoiibtU'ss the
ancients had some special reasons for making the h'ishes swim
away from each other, and the Twins face each other, but I
fear it would be only guess-work to suggest them now. It is
clear that tlie nine remaining signs, which have all one face
apiece, are arranged as I state.

Is not Mr. Arnold a little inconsistent in saying that " it is
not safe to base arguments on poetry" and tlu;n immediately
proceeding to adopt the methotl he condemns ? And how
does lie know that V'ergil was thinking of .-Xpril ? The n^al
significance of the familiar quotation from the Geurgics lies in
the fact that not only did the Kam actually "open the year"
in Virgil's time, but that it was generally recognised as doing
so. The i|uotations from (.)vi(l and Columella are as little re-
levant to the ([uestion before us as the one from Chauct;r.

Dr. Boll's examination of the planisphere of Denderah is
sutficient to show, what has long been recognised, that th.at
monument can throw no light upon the anlicinity of the con-
stellations.— E. Wai.tku Maunuku.J

The MecKaLrvicoLl StaLte
of the S\jn.

i!y I'rofeshor K. A. S.\mi'son, I'Mv.S.

A Gi.ANCic backwards at tlie theories wliitli have altenipted
to give a reasoned and connected view of current knuvv-
le(l,t;e of the Sun sugf,'ests that kn()wled,t,'e and theory are
coriiplenientary, .so much more detailed and precise was
tlieory when little or nothinj.; was known. It was from
little more than the tlarkiiess of the sunspots, with
Wilson's theory that they were de[)ressions in the photo-
sphere, that Sir William I lerschel elaborated his doctrine
of a Sun with iuhabiiaiits and luxuriant vej,'etation ; ■ and
if it is now clear tlnit we shall need an imaj^ination as
intrepid as 1 lerschel s to realise the state of the Sun, it is
no less clear that it must be a vastly more creative
imatjination. 'J'hankstophotof,'raphy,of which M. Janssen
has for so long given us such admirable examples, thanks
above all to the spectroscope, which, in its latest ap[)lica-
tions in the spectrolieliograph, actually maps out the
forms of clouds of hydrogen and calcium at different
levels of the Sun's atmosphere, we seem to have the
means of gaining some real knowledge of the structure
as well as the composition of the Sun's atmosphere.
N(jr are these the only signals that tlu;ory should hold
its peace. A fresh discussion of the sl.atistics of sunspots
and prominences by Sir Norman Lockye^r has shown

* The doctrine is not yet extinct ; t have mel jiersuns, hardly in
middle life, who learnt it at school, and held it without question.

120

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

that the familiar eleven-year period is resolvable into the
separate progresses of three or four simpler elements,
which overlap one another and severally arise and dis-
appear within seven or eight years; and a consideration
of the Stonyhurst magnetic records by Father Cortie has
served to prove how indefinable in the present state of
our knowledge is the bond coimecting magnttic storm
with solar outbursts. In the presence of rapid and
promising developments on the one hand, and increasing
doubt upon the other, reserve in formulating any theory is
unavoidable. No great confidence can be placed in
arguments not based upon consideratijns which are of
the widest generality, and cannot under any circum-
stances lie falsified; such, for example, as the laws
by which such a body must graduilly condense under the
infiuence of gravitation and loss of heat. Even here it is
necessary to make somewhat sweeping assumptions before
any precise conclusions can be drawn, and there is con-
siderable disagreement among the results at which
ditferent authors have arri\ed. Vet 1 believe some plain
and necessary outline can be drawn which will co\er
many of the most prominent facts. Though such an in-
vestigation relates more directly to the conditions prevail-
ing within the body of the Sun than to the state at the sur-
face, with which it might at first appear that we were alone
concerned, its bearing upon the latter question is intimate.
Thus Professor Schuster has said that the main differ-
ence between stars which show a spectrum like our Sun,
filled with metallic absorption lines, and those which, like
Vega, show only the absorption of hydrogen, is neither
m(jre nor less than the UKjre thorough mixing up of the
atmospheres of the former ; " if we could introduce a
stirrer into a Lyrac there can be no doubt whatever
that the low-temperature lines of iron would make their
appearance." If this be true, the stirrer we are seeking
consists of more or less violent convection currents, and
in order to form a just estimate of how efficient these
may be we should study that instability which in great
or small degree is always present where convection
currents exist.

Instability with bodily interchange of mateiial does
\isibly exist in the Sun, and must do so, or else its face
would soon be covered with a dense luask of relatively
cold matter; it is radiation which sets this instability up,
and the key to understanding it is some comprehension
of the process of radiation. For example, it should be
realized very clearly that a comparison of the radiant
energy emitted by two bodies is no comparison of their
temperatures unless they are in similar stales ; thus a
solid body maintained at a certain temperature radiates
sensibly as from its surface; but if it be finely divided,
and its parts scattered, it will radiate enormously faster
from the same temperature, since its surface will be
enormously nuiltiplied. Mence, if a sunspot appears
nearly black in comparison with the rest of the disc, or
if, as in M. Janssen's photographs, we see the whole
surface mottled over with minute brilliant spots upon a
darker background, the simplest explanation is that the
brighter parts represent matter diffused in cloud, and the
darker parts are relatively dense and conglomerate.

In my opinion, the whole internal state is dominated
by radiation, for apart from this source of loss of heat,
there is no reason why the body should not settle down
to any law of distribution of its matter in which the
density did not increase from the centre outwards. But
I must profess myself a total disbeliever in the state
of affairs whicli it is commonly asserted would in con-
se<]uence arise.

This state is Lord Kelvin's well-known " (^onvective
Equilibiinm " of temperature. I )iscuisiiig in 1862 the

state of the earth's atmosphere, and observing how winds
and other currents mingled together with great rapidity
portions of air which had been widely separated. Lord
Kelvin adopted the hypothesis that the temperature at
different levels must be such that this indifferent mingling
should not change it ; in other words, the excess of heat-
energy possessed by a portion of air at a lower level of
the atmosphere, and at consequently greater pressure and
density, must be just sufficient to expand the same por-
tion to a pressure and density in equilibrium with those
at any level above to which it may be transported. The
same law he afterwards adopted as regulating the whole
internal state of the Sun, and many other eminent
authorities have followed him, the latest and not the
least of whom is Professor Schuster. If it is true of the
Sun, we must allow that the Sun's density diminishes
somewhat rapidly from the centre outwards, while the
temperature from the surface to the centre rises with a
great rapidity, which is maintained without much decline
right throughout the whole body and reaches millions of
degrees centigrade before one-tenth of the radius has
been measured.

No doubt we must be prepared for some extravagances
in theorising upon matters so little known, but it is
at any rate safe to keep as far as possible from tempera-
tures measured in millions of degrees ; and in spite of
the long acceptance of the theory of convective equili-
brium in the Sun and the formidable array of authority
by which it has been adopted, I confess I can find no
reason why it should be supposed to exist. On the
contrary it appears to me that if we can imagine it to be
artificially set up, it would require forces to maintain it
for which the circumstances make no pro\'ision. For if
a body of gas were arranged according to this law, behind
some screen which prevented it from losing energy by
radiation, and the screen were then removed, wliat would
happen ? All portions would commence to lose heat, the
outer portions very rapidly by mere radiation; but the
inner portions also, in part by radiation, because they
were less screened outwards than inwards, but chielly
because the outer chilled portions which had already
lost the heat that allowed them to maintain themselves
at the higher level descended upon them and shared in
their stores. This would go on without any attempt
on the part of the body of gas to restore the state of con-
vective equilibrium, because no instability would occur
which would give rise to convective currents mingling to-
gether the matter from separated regions, until the body
had departed materially from the rapidly- varying density of
convective e(iuilibrium and had passed that of a density
uniform throughout the mass. Even then the currents
would only be proportionate to the degree by which a
uniform density was overstepped, and except at the outer
surface, where it is impossible to escape from a high
degree of instability and conser]uently violent convective
currents, the density would apparently be left in a state
which might perhaps fluctuate a little, but would be but
very little removed from a state of uniformity. It would
follow that the temperature was also substantially the
same throughout the bulk. Or again, if we reverse our
attitude and suppose a body set up with density and
temperature nearly uniform throughout its body, but on
the whole very slightly increasing outwards and therefore
liable to slight convective currents— excepting at the
surface — and ask what forces would be found which could
materially disturb such a state, none can be mentioned.
Kadiation which appeared as an acting cause lending to
set up such a state will be inoperative when that state is
attained — excepting again the surface — and conduction
also, if we cho'e to consider it, would be inoperative with

Jl'NE, 1904.]

XOWLKDGi: .V SCIENTIFIC N i:\VS.

121

NORTH

I-

SOUTH

Photograph of a Group of Spots and of the GranulaLtions of the Solar Surfa.ce,
taken at the Meudon Observatory, 1884, April 1, lOh. 46m.. G.M.T.

122

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

a uniform temperature. At the surface, however, there
will be a wide difference ; between the rapid loss by
radiation and the rapid restoring currents from below,
no permanent or equable balance can be maintained ; the
slow currents from within, which tend to make their way
outwards under the tendency of the bulk to settle down
with greater condensation in its outward parts, here burst
forth with a violence which all can see, and having
parted with their energy, return nearly as precipitately.
I Radiation, then, is the dominating factor in the distri-
bution of temperature and density within the Sun, and
it will be noticed that in showing it to be so no assump-
tion has been made as to the law by which it proceeds.
If we wish to put our conclusions in a numerical shape,
such assumptions cannot be escaped. For example,
Stefan's well-established law of radiation, according to
the fourth power of the absolute temperature from the
surface of a " black body," does not apparently permit
any conclusions to be drawn as to the law by which a
gas would radiate. Between imperfect physical know-
ledge on the one hand, and mathematical difficulties on
the other, nothing can be done except to produce a more
precise illustration of the foregoing argument, and to
show that the conclusions will stand scrutiny. This I
have done in a paper published some nine years ago.""

There are two other general problems presented by the
Sun which appear to invite solutions upon general
mechanical principles. The first of these is the eleven-
year period in solar activity. But as to an efficient cause
for it, or even any calculable phenomenon which could
follow its phases in a similar period, we seem to be still
quite in the dark. An attempt has been made to repro-
duce such a period by a combination of tidal effects pro-
duced by Jupiter and Saturn ; but the result is uncon-
vincing, because the tide produced must be at most very
minute, and the coincidence of period is dependent upon
a hypothesis for which no reason can be assigned as to
the relative intensity of effect of the two planets. In
fact, we know as yet too little of the phases of this cycle
to hope to theorise upon it successfully. Any real ex-
planation must cover the more detailed description which
Lockyer has given, to which allusion has been made
above.

The second problem to which I refer is the law of rotation
of the surface, by which the equator of the Sun rotates most
vapidly, and parts in lower latitudes rotate more rapidly
than parts in higher latitudes. The law was discovered
by Carrington from motions of the spots, and was at
first believed to refer to the spots, but in the hands of
M. Dun&r, the spectroscope has proved that the property
belongs to the whole photosphere. If we do not mark
off the photosphere from the rest of the body of the Sun,
this law contains, I believe, no mystery. If we suppose
that in the course of its condensation in the past the
inner strata of the Sun were to be found rotating faster
than those outside them, it can be proved that as soon as
the body had condensed to a compact Huid consistency
so that the internal friction of its relative motions came
into play, a law of rotation identical with that exhibited
in the vSun woulil deselop. But perhaps more striking,
though less complete than a mathematical proof, is an
illustrative experiment that was carried out some years
ago by M. Beloposky, who filled a glass globe with water,
carrying powdered stearin in suspension, and whirled it
on a whirling machine until a uniform rate of rotation was
taken up by the whole. The glass was then stopped and
the motion of the water as exhibited by the particles in
suspension was watched. The circumstances were now

•Memoirs Royal Astronomical Society. Vol. LI.

in substance just such as I have sketched above, and the
apparatus exhibited just such relative motions as the
Sun displays, individual particles travelling spirally from
the equator towards either pole, with an angular motion
which was less for greater latitude, ultimately passing
inwards radially into the body. This last detail seems to
convey also a suggestion of activities limited to special
zones that may prove fruitful.

Photograph of the Solar Granula-tions.

In the accompanying plate we give a reproduction on a
reduced scale of part of one of the magnificent photo-
graphs of the solar surface, recently published by
M. lanssen in the " Atlas," which we noticed in the
April issue. The wonderful manner in which the
minute structure of the solar photosphere is brought out
in M. Janssen's superb photographs is due principally to
the care which he has taken to secure two points — the
one that the photograph shall be taken by light which is
practically monochromatic, so that the image is as sharp
as it is possible to obtain it ; the other that the exposure
shall be extremely short, so as to accentuate minute
differences of brightness in the most luminous portions
of the disc. It will be noted that the photograph is so
under-exposed that in the present reproduction the penum-
bra;' of the spots are perfectly black. They were not
absolutely featureless in the original, but were exceedingly
faint, the darker portions of the sun being thus sacrificed
in order to secure the maximum of detail in the more
brilliant parts. The intensely granular nature of the
disc and the thatch-like structure between the spots are
very clearly seen. This particular region of the sun
does not show any strongly developed instance of the
blurring of the granules ; but here and there small
smudged regions show themselves.

The original of this photograph was taken on April i,
1884, at loh 46"^ G.M.T. The group of spots in the
centre of the field is the one numbered 1343 in the
Greenwich series. It was a sudden outburst, the day
of the photograph being only the second of its exist-
ence. Its area at the time was 177 millionths of the
sun's visible hemisphere, or slightly over 200 millions of
square miles. The group increased in size with great
rapidity. On April 2 its area was nearly five times as
great as on April i, and l)y April 6 the group was one of
the largest seen during the entire 1882-1884 maximum.
It returned to the visible hemisphere on April 21. I )uring
the thirteen days that it was under oliservation at this
return, it was gradually diminishing in area; the leader
spot being as usual a circular spot of regular structure,
and much more stable than the rest of the group. Before
the group disappeared at the west limb on May 3, the
leader was the only survivor. The leader was seen again,
still as a well marked circular spot, during two further
returns. It slowly diminished in size, and was last seen
on July 12, when it had shrunk to an area of no more
than six millionths of the solar hemisphere. The entire
life of the .group was thus 103 days.

The scale of the accompanying photograph is one of
^^ inches to the diameter of the sun.

Mr. J. \V. Jarvis, l'\r,.S., St. Mark's College, Chelse.i, S.W.,
has been appointi-d Cl.iss Secretary and Class Treasurer to
the London C.eolosical Field Class. The excursions this
season are to Mcrstham on April 30, and to I'urley, Henley,
Wimbledon, Aylesford, Leighton, liedford, Chislehurst on
succeeding Saturdays.

Jl-NE, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

ASTRONOMICAL.

Comet 1904. ' (Brooks).

After an interval of seven months, during which no comet has
been under observation in the northern liomisjihcrc, a now
comet was discovered by Professor W. H. Brooks, director of
the Smith Observatory, Geneva, U.S.A. The new object, as
the following elements by Herr E. Striimgren will show, has
almost exactly the same perihelion distance as the comet dis-
covered by M. Giacobini, December 2, 1902. Only one other
comet is known with a perihelion distance greater than these,
namely, that of 1729. An examination of the Harvard photo-
graphs taken before the discovery of Brooks' comet furnished
six plates, showing objects which might possibly be identical
with it. These were taken on March 1 1 and 15, and April i, 5,
13, and 16. The first two places have not as yet been satisfac-
torily included in any orbit, and possibly the images shown on
these two plates do not in reality belong to the comet. The
nebula; N.G.C. 6555 and 6564 are in the innnediate neighbour-
hood of the place indicated by the plate of March 11. At the
present time the comet is receding both from the earth and
from the sun, and is slowly diminishing in brightness. This
makes the twenty-fourth comet discovered by Professor
Brooks.

Elements.

T = 1904, Feb. 28, 8130 M.T. Berlin
u = 50° 51' 30"

a= 275° 17' 3^-

i = 124° 59' 38"
logq = 0-42951

1904-0

Methods of Determining Jovian
Longitudes.

In the " Monthly Notices " of the Royal .Astroiioniical Society
for March, 1904, Mr. Stanley Williams institutes a comparison
betv/een the method of determining tiie longitude of markings
on Jupiter by estimating the times when they appear to be
exactly in mid-transit with the method of measuring their dis-
tances from the two limbs of the planet Ijy a micrometer ; and
he gives good reason for thinking that the first and simpler
method is, in the hands of a practised observer, not at all
inferior in accuracy to the latter. The micrometric method
h.as been supposed the better from the comparison of measures
of the s.ame object made on the same night ; oljviously transits
of any object can only be compared ;is taken on difierent
nights. Mr. Williams has in this paper compared micru-
metric measures made of objects on different nights, and finds
that they show no superiority in accuracy over the method of
transits.

* * *

Change from Taurus to Aries as First

Sign of the Zodiac.

The same number of the " Monthly Notices " contains a paper
by Mr. and Mrs. Walter Maunder, in which they show that
there are clear indications in Assyrian records of two distinct
methods having been in use for the determination of the begin-
ning of the year. The earlier was that of the seleniacal setting
of Capella. This involved the recognition of Taurus as the
first constellation of the zodiac, and was no doubt in opera-
tion as early as 2000 B.C. The second was the direct deter-
mination of the equinox by some form of time-measurer.
Other advances io connection with this seem to be indicated ;

the recognition of the ecliptic as distinct from the equator; of the
ascending node ; of the nature of the motions of some at le;ist
of the planets; and the division of the ecliptic was elTeeted
into twelve equal signs as distinct from the twelve irregular
constellations. The dale when tlu;se changes took place
cannot have been very different from tliat when tlie star
Hamal, the briglitcst of the constellation Aries, marked the
spring colurc, i.c'., about 700 B.C., and the remarkable out-
burst of scientific activity which is thus indicated was in ;ill
probability associated with the great literary activity of the
reign of Assurbanipal.

The Astrographic Catalogue.

It is now seventeen years since the delegates of seventeen
different nationalities met in Paris, under the presidentship of
Admiral Monche-z, to consider the question of a photographic
chart of the whole heavens, down to the stars of the fourteenth
magnitude, with a catalogue of stars to the eleventh magni-
tude. The latter portion of the programme is now beginning
to be realised ; the Potsdam observatory has already produced
three volumes of its catalogue; the observatories of I lelsingfors,
of P.aris, and of the l-'rench colonies have also begun to pul)-
lish ; and the Astronomer- Royal, at the meeting of the Royal
Astronomical Society, already alluded to, presented the first
volume of the Greenwich catalogue, covering one half the
Greenwich section. The introduction to the catalogue con-
tains a number of exceedingly interesting discussions ; of the
effect of personality on the measurement of the places of
stellar im;iges, of the probable error of the measures, and ol
the determinations of photographic magnitudes. The accuracy
of the measures of position are of the same order as of obser-
vations with the transit instrument ; the probable error of the
position of a star, in arc of a great circle, deduced from the
measures on one plate is + o'26" in R.A., and + o'ZiS"
in Declination. In the investigation of photographic magni-
tudes, it was found that in passing from one exposure to
another the law, exposure X brightness equals constant, held
almost exactly, except in the case of the shortest exposures,
which gave fainter stars than would be expected in accordance
with the law.

Distribution of Stars of the Third and
Fourth Type.

In a discussion of the distributiun ul'the coloured stars, Ilerr
Freidrich Kruger gives in the " Astronomischc Nachriehten,"
No. 3947, a table dealing with 3>Soo stars of the third and
fourth types of spectra. These are distributed into eiglit
zones, each twenty degrees in breadtli, the galactic eijuator
running through the middle of the fifth zone. The table shows
that about 4 per cent, of the stars of the third type of spec-
trum are known to be variable, but 14 per cent, of the fonrth
type. Both cluster towards the galactic equator, but tliat
clustering is nuicli more evident with the fourth (ype stars.
These two relations were drawn attention to by Professor
Hale in his recent " Memoir on Stars of the h'ourth Tyi>e."
A curious point of difference between the two types is shown
by Herr Kruger's table, namely that whilst tlie numbers of the
third typi: show but very small increase with diminution of
magnitude, the faintest class of the fonrth type includes more
than all the other six classes combined.

The Spectroscope Binary, Iota Pegasi.

Professor W. \V. Campbell discovered in i'-ii)9 llial Iota
Pegasi was a spectroscopic binary, and Mr. Heber D. Curtis,
from a very thorough discussion of forty-three photographs of
the spectrum extending over six years, has obtained very
accurate final elements for it. The period found is 10-21312
d;iys, and the velocity — 4- r2 kilometres. The orbit is nearly
eiicular, the eccentricity being o-oo«5, so that the epoch of
periastron is not very certain. Dr. R. G. Aitken examined
the star in 1901 with the 36-inch refractor of the Lick
Observatory, but was not alile to detect any evidence of
duplicity.

124

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

The adaptation of the Forty-Inch Visual
Refractor of the Yerkes Observatory
to Photography.

In till' original design of the forty-inch refractor of the
Verlies ( )bservatory, no provision of any Uind was made for
direct photography ; there is no gniding telescope to enalile
lengthened exposnres to be given, nor photographic corrector
to firing the actinic rays to a focns on the sensitive plate.
Mi. (i. 'I'. Ritchey has overcome the first difficnlty by means
of an eyepiece magnifying abont one thons.uid diameters,
placid in the side of a donble slide carrier. A small diagonal
prism receives the light of the gniding star, and refiects it at
right angles into the eyepiece, and this with its accessories
are monnt<'d on a slide which can be moved to any desired
position on tlie upper side of the rectangular bo.x, and firmly
clamped there, so as to assist in finding a suitable guiding
star. The star is brought to the intersection of the cross-lines
in the ejepiece, and is Uept there throughout the exposure of
the sens live plate. The observer sits with his eye at the
gniding eyepiece and his fingers on the two screws which
move the slides, and thus he introduces any minute correc-
tions of position which he sees are necessary. These correc-
tions may be on account of either the irregular movementsof
the driving clock of tlie telescope, or more frequently from the
tremors in the atmosphere. The latter irregularity may
reipiire correction several hundred times in a minute, and a
practis-'d ob.=erver can introduce between one and two
hundred per miunte. The other difficulty — that the instru-
ment is a visual one — Mr. Kitchey has obviated by the n.se of
a delicately tinted yellow screen. This screen utilises the
ravs of light which are most freely transmitted by a large
objective; since it is a well Unown fact that while only a
small percentage of the yellow rays are lost by transmission
throirih a Large and necessarily thick ol)jecti\e, a veiy large
percentage of the blue rays are. Consequently the forty-inch
visual objective, thus used with a yellow screen, and plates
sensitised to the yellow rays, is scarcely less rapid, if at all,
ni photographing stellar images, than an ofiject-glass cor-
rected for blue rays would be. In two hours it registers stars
of approximately the seventeenth magnitude, which are at
the visual Hunt of the instrument ; and in five hours can
register stars of a magnitude fainter. The yellow screen is
formed from two tliin and transparent plates, finely ground
flat and highly polished. One of these plates, wliich are S by
10 inches, is flowed over with a collodion film of a delicate
yellow tint, and when the film is dry, this is covered with
Canada balsam, and the other plate bound on it as a cover
glass by adhesive tape. When in use it is laid close upon
the sensitive plate, nothing separating them but the tape.
Mr. Ritchey has been most successful in photographing por-
tions of the moon's surface, and close clusters of stars, and
in Vol. VHI. of the Decennial Publications of the University
of Chicago, several very fine specimens are given, notably one
of the lunar cnitcr Theophilus and its surroundings, which
perhaps shows the detail on the moon's surface more clearly
than any otlicr photograph ever taken. In the photographs
of the clusters Messier 13 and 15, the original neg.itives and
transparencies from them show the star images separ.ite and
distinct, even at the very centre of the cluster, but in the pro-
cess reproductions given in the volume the smaller and nearer
stars are mi^rgcd together. With nebula; the yellow screen is
not so successful since these are lich in their proportion of
green rays, which do not come to the same focus as the
vellow.

■«• * *

Photographs with the Two-Foot Reflector
of the Yerkes Observatory.

Seven very fine specimens of Ihc woi k done with the two-
foot reflector of the Yerkes ( )bservatory are published in
Vol. VIII. of the Decennial I'nblications of the University of
Chicago. These are of the two giant nebula- of Orion and
Andromeda ; of the spiral nebuhe Messier ;5 Tiiangnli and
Messier 51 Canum Venaticoriin ; of the c.irded-wool-like
nebulosity in the Pleiades; and of tlie torch-like nebuhe in
Cygnus known as N.G.C. 6960, and N.G.C. ht)i)>. These two
last form part of the same extended nebulosity, but they

present some striking differences in their relationship to the
stars. In the first ease the nebula seems to act as a wall or
barrier separating a region strewn very thickly with stars,
from a sparser field ; in the other case no such difference in
the numlier of the stars seems to exist on the two sides of the
nebul.i, which itself appears to lie in a district of few and small
stars.

'i^<ti^t^(ti

ZOOLOGICAL.

Mosquitoes in England.

Di'Siu rr; the coldness and wetness of the season, mosquitoes,
according to the " Report on Economic Zoology," issued by
the Trustees ot the f-Sritish Museum, .appear to have been
unusually numerous in England last summer, and to have
caused much annoyance and inconvenience. They were
■\cry prevalent in parts of b^ssex, especially in the neighbour-
hood of hipping I'orest, and also in Kent and Surrey, notably ■
along the \allcys of the Thames and the Kennet, and in the
marshes bordering the lower courses of the Thames and the
Lea. They were also reported as having caused much annoy-
ance near Bristol, at Great Staughton, Huntingdonshire, and at
Weston-super-Mare, Worplesdon, Colchester, Canterbury,
and Birchington. Although complaints of mosquito bite are
received almost yearly from the Thames Valley, last summer
the in.sects in question .seem to have been unusually virulent,
causing such swellings that medical attendance was in soiiie
instances recjuisitioned. The species most abundant were the
conmion gnat [Cithx pifticm) and the banded gnat {Tlicubalilin
auniiUitii), the latter of which does not usually attack man. This
reminds us that we fail to see the reason for dropping the
good old English word "gnat" in fa\our of the foreign
'" uioS(]uito," now th.il both are known to be the same.

■X- * -X-

A Deer-like Antelope.

Hitheito there has been supposed to exist a sharp distinc-
tion between deer and .antelopes, according to the nature of
their horns ; but recent discoveries iu North .America tend to
show that this distinction is only a fcatnre of the present day.
Deer, it is almost superfluous to mention, have deciduous
bony antlers, while in antelopes the horns are covered with
hollow sheaths, which are never shed and never branched.
The .American prongbuck resembles antelopes in its skeleton,
but its horns are forked. The new fossil type combines the
skeleton and teeth of an antelope with the antlers of a deer.

New British Mouse.

According to a note by Mr. W. IC. Cl.irkc inthi Proceedings
of the Royal Physical Society of Edinburgh, the mou.se of the
l-";croe Islands is a large and stouter built animal than the
rommoii house mouse, from which it also differs in colour.
It is therefore regarded as representing a distinct local race
of that species. St. Kilda has also a pecnli.ir mouse of its own.

A Rare Bird at the Zoo.

The Zoological Society's menagerie in the Regent's Park
has recently received an interesting and valuafile addition in
the form of a specimen of the South American boat-billed
stork {Citiuhroiiui cochhnr'ui). It is many years since this
species, which, by the way, must not be confounded with the
shoe-bill of the White Nile, has been represented in the
collection.

•>;■*»

New Egyptia-n Fossils.

(ircal interest .attaches to the dcscri|ition by Dr. Fra.is, of
Stuttgart, of certain very remarkable fossil niammaliau
remains from Lower Tertiary marine strata in the Mokattam
range, near Cairo. These specimens serve to show that a
gigantic Tertiary whale-like creature, known as Zcui^kniun
(of which the remains were first discovered in North America),
is the direct descendant of the primitive land Carnivora of

June, 1904.]

KNOWLEDGE cS: SCIENTIFIC NEWS.

125

the eaily Tertiary: the nowly-discovorcd tonus bciiii;
actually the inissinj; links. Hitherto, /cii-^hhiini itsrHhis horn
•jnuT.ilK los^.inifd as an aiicestr.il ty|H' of wlial.-, Iml lliis.
accorilins; to Dr. Kiaas, is incorrnt ; lliit criMtiirc, .illlioM^li
mariiu', liavinj; no sort of allinily willi the Ci lacci. It this
be fo, we have still other niissiiij; links to disiovi 1. iiaim ly.
the progenitors of the latter ponp.

Fish Scales.

We may now, it seems, ascertain the a.s^c- of the co<l and
haddock sent to ns by our fishmonger by the examination of
their scales. For it appears, aceordinii; to recent rese.irciics,
th.at the scales of these fishes, like those of carp, d<\< lop at
intervals certain well-marked rings, which appear to indicate
the limits of the annnal growths.

An American Hedgehog.

The discovery in the middle, or Oligocene, Tertiary deposits
of Dacota of the remains of an extinct specitsof hedgehog may
not appear to non zoological re.aders a matter of nmch ini
portance. In reality it is ,a fact of the v< ry greatest interest,
for hitherto the hedgehog tribe {liiiiuucidu) has been regarded
as an exclusively Old World group. The discov('ry of the
fossil .American species (which has been made the type of a
new genus, under the name of Pnttluiix, and is described in
the xixth volume of the HulUlin of the .American Museunii
serves to strengthen the view of those who maintain that thi'
northern coimtries of both the Western and ICasleni Henii
spheres form but a single zoological region ; .and th.at formeily
there was comparatively free conmiunication l)etwecn llicm in
the neighbourhood of Hehring Sea, under climatic conditions
which permitted of temperate forms passing from one conti-
nent to the other. When we know ninreof th<' Tertirny fauna
of Eastern Siberia, it is probable that the number of groups of
animals confined to one or the other JKniiisphere will be still
further diminished.

Fish Destruction by Birds.

At a recent meeting of the I'lella.-I Natural Ili-tnry and Philo-
sophical Society, Mr, J, l>rown gave reasons for concluding
that there are 2,000,000 gulls in the I'nited Kingdom, and that
duriog the herring season each bird destroyed 200 fry per dav,
or i2,(X)o during the two months of the sea.son. These, if they
had come to maturity, would h;i\(' been worth /"24,ooo,ooo.
He, therefore advocated the di^struction of the gulls, each of
which cost the nation /'12 in two months in consequence of
their protection by -Act of parliament. If we add to the dam-
age done to herrings by gulls tlu' loss inliicted on these and
other fishes by cormorants, shags, gannet:-', guilU-mots, Xc,
there can be no doubt that the supply of food fishes is enor-
mously (bminished ; and it seems little short of folly to be
spending vast sums of mone)' on the m.iiulen.ance of fish-
hatcheries at Piel and other places, and at the same time to
do all we can to ensure the destruction of valuable fishes
by encouraging the increase of their natur.il enemies. I->irds,
are, no doubt, charming adjuncts to scenery — both on tin;
coast and inland — but such ornaments may be bought too
dearly.

■k * *

The Destruction of Whales.

In the course of a \ ery iuleresting |)a|)iT on whales and
whaling contributed to llie April number of the Annals oj
Siollisli Sdtiiral lUstorij, Mr. T. .S jutliwell tells us that whereas
between the years i.Si.( and 1.S2; no less than 12,907 Oeeu-
land whales were killed olf Greenland and in Davis Straits by
British vessels, only 127 were accounted for in the ten years
ending with 1902. Comment is superlluous.

Papers Read.

At the meeting of the /nological Society, heUl on April 19th,
Mr, O. Thomas exhibited the skull and skin of a h.artebeest
from Uganda, which were regarded as representing a new

species; and .also skulls of the North .Australian rock-w.illabv,
a s^pecies rem.arkable for developing an unusually Large sc-rie-i
of molar teeth, whioli are eonliniiously slieil .uid renewed.
This s.une geulK-m.ui, in coll.d)oiMtion with Mr, Schu.iuii,
n-.ul .1 p.iper on trteutyoue species of mauini.als eollirteil
during the work ol the Hoinid.ir\' C'oiuniission between I'lrilish
and Ciermau l-^ast .Africa, of which three were reg.irded as new
to sci(Uice. Mr. liedd.ird contributed the second instaliu<'nl
of a series of papers on the anatomy of li/artls, dealing in this
inst.ince with the South .Anieric.in leguixin; Mr. ISonlenger g.ivc
addition.d information with regard to the skeleton of the ixtinct
Scots reptile I lU-ifclnin ; while Dr. Uroom described the sti uc
ttire and mode of articulation with tln' fkiill of the lower |.i\v
of some of the extinct mammal like reptile^ of South .Abica.
l'"in;dl\', Mr, Druce gave descriptions of three-aud-tvvcnty le-w
South American butterfiif s. At the meeting of the same bodv
on May 3rd the following four p.ipers were re.id, n.iimU' : Mr.
'I hom.is on the osteology .and systematic imsition of llu-
M.dagasy bat .Wvve/'di/i; iinrilii ; Mr. Beddard on c 11 l.iin
features in the vascular system of ch.amcli-ons and other
li/ards; Mr. .A. D. Iniins on the gill r.ikers of the sturgeons
of the genus Patyihlon \ .lud |)|. Kideudod on the skulls of
cert.ain bou\' fishes. .A sketch was exhibilcil ol a young
.African eleph.ant rem.irk.-ible for the .■unoinit ol h.iir on ils
body; and .1 |)liotogr;iph was shown of the last <)ii.igg.i living
in the menagerie. .At the Cicolo'^icd .Socii'ty on .April ^ytli.
a new species of fossil scorpion from thi' (d.diueasure-; of
L.auc.-ishire was described by Messrs. Baldwin .lud Siilc lille.

Mr. W. Koyal-D.awson writes; — With reference to the Note
in last month's " Knowi.i-.dgi- " ip. ijfi) on the prior oiieuing of
the right eye, I may state that out of a litter of eight t;ime
whit(; rats born a short time ago no less th.in seven opened
the right eye first, while the eighth showed no lenden(;y to do
so. I think this will suffice to confirm the su]iposition that
the right eye is the first to be opened in the order Ro.tcnt'ui.

%^^'i'i^

BOTANICAL.

An ;disfr.icl of Mr. (i. Massee's interesting [iiper "On the
Origin of Parasitism in h'uugi," which has r('C(nitiy been pub-
lished in full in the I'/iilnsa/'Inial I rtinsntlinns of the Royal
Society, is given in the Society's Procccdini^s, ;ind also in the
Annuls 0/ lUiliin;/ for April. The author explains why it is
that a certain parasitic ftmgus is often only eap;ible of infect-
ing one particul.ir species of plant. Though the spores of
these fiingi germinate freely on the sutface of any pkint when
moist, inlection is confined to the particul.ir species of pl.iut
which is the usu.al host of the p.ar.asite. This sel'_cli\e power
is .atlriliuti d to chemolaxis. The presence of sacehajosi; in
the cell sap of the' host plant is found to induce iuleclion by
many sapioph)lic ;uul par;is tic fungi, unless Ihe inlbieuce of
this .itli active or posit i\ely chemotaclic substance is overcome
by the presericc of a more powerbil negatively cheniotactic or
repellent substance. Apples, though eout.iiuiug siceharosi,
are immune Irom the attacks of I'ntiytis luicri-ii, which pre_\ s
on a greater number of dilfi'reul pkmts lh;iu any olhi-r known
par.isitic s,,(;cies. This ininumity is due lo the presence of
malic acid, which is repellent or neg;itively cheniotactic lo
the germ lubes of this particular fungus, l^xperinieuts havc^
shown that a fungus can be induced to attack the leaves of a
pl.int, on whic-h it is not ordinarily parasitic, by injecting into
them the subst.aiice which is known to be jiositivcly eheme-
faetic to its germ tubes.

In the Annuls nj Ilaliiny for .April, Mr. J. P.ukiii c.ills ;itl<'U-
fion to the nectaries on the bud-scales of the Para Rubber
tree, llcvca hnisilicnsis, apparently the only plant that pos-
sesses them on these organs. The l'"uphoibi;ice;e, to which
llivi-a belongs, contain numerous species in which extra-fior.il
nectaries ;ire jireseut, usually on the stem or on thi^ l.iniin.a or
petiole of the leaf. Ilci'ca akso has them on the leaves, and
various n-ferenccs to these have been made by writers, but
the nectaries on the Inid-scales seemed to ha\e been over,
looked altogether. This is probably due, as the author

126

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

explains, to the fact that an adult tree of the Hcvca " puts forth
fresh foliage annually, and the bud-scales being caducous,
are merely evident while the shoots are in the immature con-
dition." The honey secreted by the nectaries encourages the
visits of ants, whose presence assists in safeguarding the
developing foliage from the attacks of injurious insects.

PHYSICAL.

The Emanation from Radi\im Bromide.

Til show the diltusion of the cuianation from radium bro"
niide. Mr. T. Indricson, in a paper recently read before the
Russian Physico-Chemic.al Society, used a long tube, the in-
ternal surface of which was coated with a layer of zinc-
sulphide. On connecting the apparatus with a test-tube
containing a solution of radium bromide, luminescence was
found to appear and to be prop.agated throughout tlie tube.
On rcpc.iting Ramsay's experiments, the author found that
the yellow helium line did not coincide with the yellow lines of
the spectrum given by the emanation, but was situated between
the two yellow lines of the emanation. When the serpentine
coil conununicating with the tube was dipped into lir|uid air. a
strengthening of the lines corresponding to the helium line was
noted in the spectrum of the emanation, while between the
two yellow lines above referred to a third line, coinciding with
the yellow line of helium, appe.ai-ed. The lines of helium do
not exist in the spectrum given by the emanation of a freshly-
prepared tube, but only appear afterwards. On observing the
gases set free on the dissolution of radium bromide, it was
observed that the helium lines did not appear as long as the
spectrum tube preserved its phosphorescence in the dark.
After four days this phosphorescence would disappear, and the
lines of helium could be noted in the spectrum. — A. G.
* * *

Action of Ratdium on Metals.

In order to investigate the action of radium on metals,
N. Orloff, as pointed out in a paper recently read before the
Russian Fhysico-Chemical Society, covered, in April, 1903. an
ebonite capsule containing 0-03 gm. of radium bromide with
an aluminium plate o'oi mm. thick, instead of the mica gene-
rally used. In the course of July the author, on opening the
capsule, noted on the surface of the aluminium turned
towards the radium some protuberances of the same aspect
as the surrounding surface of the aluminium, and resembling
small drops of melted metal. These protuberances proved to
be radio-active, producing a photographic image on acting for
some minutes through bl.ack paper : and even after six months
they were found to emit invisible radiation without any appre-
ciable weakening. The author thinks that a stable alloy is
formed by the accumulation of material particles given off
from the atomic systems of radium, around small aluminium
nuclei. — A. G.

•* ■» *

On Radio-Active Ennanation from
Water and Oil Fountains.

In a paper published in No. S of the Physikalischc Zcitschrijt
(April 15, 1904), Prof. F. Himstedt arrives at the conclusion
that radio-active bodies giving off a gaseous emanation are
widely diffused throughout the earth ; these emanations are
absorbed by water or by petroleum, and after having been
conveyed along with the latter to the surface of the earth, will
thence diffuse into the air. Because of the many analogies
noted between these emanations and radium emanations, the
author thinks it possible that both are identical. In this case
the ores of uranium, from which radium emanations are de-
rived, would either be widely diffused or else there would be
some further matters possessing, though to a lesser degree, the
property of giving off emanations. Considering that the ab-
sorption coefficient of water, as well as of petroleum, with
respect to this emanation, is found to decrease for increasing
temperatures, while hot fountains, on the other hand, show an
especially high activity, the hypothesis is suggested that the
amount of radio-active mineral increases with increasing
depth. The radio-active components of the earth should,
therefore, possibly be allowed for in estimating the tempera-
ture of the earth's mass. — A G.

ORNITHOLOGICAL.

By W. P. PvcRAFT, A.L.S., F.2.S., M.B.O.U.,&c.

Gloss ylbis in the Orkneys.

The "Annals of Scottish Xatnnil History " for May contains an
account of a Glossy Ibis, Ibis Jnlcindlus, shot a mile west of
Stromness on September 19 last. According to Mr. Eagle
Clarke this is only the second occurrence of this bird in the
British Islands, the first having been shot in iSjy near Kirk-
wall. Some mistake has certainly been made here; for which
Mr. Eagle Clarke can hardl\- be responsible. So good an
ornithologist doubtless knows that at least thirteen instances
of its occurrence in Great Britain are recorded, one of these
being from .Vberdeen-shire — October 4, 1880. According to
Mr. Ussher there are no less than twenty-two instances of its
occurrence in Ireland.

* * •*

Rough-Legged Buzzard in Co. Down.

The Rough-legged Buzzard. iUitm tiii^opns. is only a rare
visitor to Ireland. According to the Irish iS'iitnralist (May)
a specimen v/as shot in November last in Co. Down —
the fifth in Down. This appears to be the tenth recorded
instance of its occurrence in Irish territory.

Stone-Curlew: Co. Donegal.

An example of this rare visitor to Ireland was obtained on
< )ctober 12 last in Co. Donegal. This is the first time of its
occurrence in Donegal. Only ten other cases of its occurrence
in Ireland are on record, and eight of these, it is interesting
to note, were obtained on the East Co.ast.

* * *

Ravens Nesting in Captivity.

Instances of ravens breeding in captivity are rare; and
cases of successful rearing are still more so. Mr. W. H.
St. Quintin's note in the Field (May 7) to the effect that he has
in his aviary a pair of young that are nearly ready to leave the
nest is therefore of considerable interest, especially so having
regard to a certain police court prosecution which took place
some time ago.

* * *

Great Crested Grebes at Richmond.

Mr. Gordon Dalgliesh sends us some interesting notes on a
pair of these birds which he has had under observation since
April 17 last. They have taken up their quarters in the Penn
Ponds and appear to be breeding. When preening the breast
feathers, he remarks, these birds turn over on to their backs
and do not perform this operation when sitting upright as one
would imagine. " The female, when she landed, did not stand
upright, but dragged herself along on her belly."

Colour, and Coloration in Birds.

An extremely interesting and important paper on this sub-
ject was read by Mr. T. Lewis Bonboteat the Linnean Society
on Ma}- 5, to which we hope to be able to refer later.
Briefly, he contends that bo;h colour and coloration are prim-
arily due to physiological causes, and that the varied patterns
and tmts of plumage which distinguish different species are
determined by the action of natural selection on these " ex-
pression points " of "vigour."

There is an intimate connection, he contends, between the
bleaching process which takes place previous to moulting, and
the development of conspicuously marked areas. These in-
deed, he holds, are nothing more than permanently fixed
bleaching, or intensification areas, which he terms " pitcilo-
meres."

Messrs. Newton and Co., who have held appointments to
the Royal Family continuously since i860, have this week
been honoured by a Warrant of Appointment as Scientific
Instrument Makers to H.R.H. the Prince of Wales.

June, 1904.]

KNOWLEDGE e^- SCIENTIFIC NEWS.

127

Ba^cteria and RoLdio-
Activity.

By the kindness of Pr. Al.in (irccn wc are aMe to repro-
duce two photot^aplis sliowins the effects that liactcria wliich
have been snlniiittod to the action of radium lironiidc, produce

Tuberculosis hacilli.

on photographic plates. Small masses of bacterial growth were
exposed to the li and -, rays of 10 milligramiiies of virtually pure
radium bromide. In a large number of inst.uiccs such masses
when removed from the influence of tin; radium and placed
between two thin sheets of glass, themselves 'not radio-active,
were capable of so affecting the sensitised film nf a photo-

graphic plate with which they were brought in contact that, on
(levelopment in the ordinary way, the platfi showed a dark
area corresponding to the shape of the l)acterial mass. The
photo-actinic rays proceeding from the bacteria which had been
exposed to radimu were capable of affecting a photographic
plate through a double layer of lead foil. The rays thus
(Miiitted seem to coincide with the ;:f rays of radium, for they
are slopiied by a suOicieut thickness of lead. If any 7 rays
are emitted bv the bacteria they do not appear to affect the
photographic plate. It will be remembered that some years
,igo Or. Johnstone .Stoney remarked that the microscopic
dim(Misions of bacteria might lie due to the necessity of
deriving their energy from the slower moving molecules of
substances with which llii^y were in contact, and more lately
il hasbfcn suggest(;d that the energy of radium might be due to
th(! .ni.dogous power of that element to derive ils <'uergy from
outside som-ces by sifting out the molecules of different speeds
impiTiging on it. This theory, now recciveil with Ic^ss uu.ini-
mity than the Kutherford-Ramsay-Soddy theory of the dis-
integration of the atom, is neither confirmed nor disproved by
Or. Al.in Creen's experiments, which appear to show thai
bacteria, so far as ac(|uired radioactivity iseoueerne<l, beha\e
like other substances. ( )ne of our jiholographs shows the
blur made by a mass of tubercle bacilli on a plate; the other
the elfect similarly produced by anthrax spores. The .acquiicd
radio-aclivitv lasts in some instances for over six weeks.

A Stereoscopic Single
Lens.

A Ni;\v method of obtaining stereosco|nc photographs, .and
stereoscopic effects when looking at them, has been designed by
Or. M. Von Rohr, of the Carl Zeiss firm. Its peculiarity is
that the effects are obtained by a single lens directed at single

Spores of Anthrax.

Viewing througli the Single Lens Stereoscope.

I 28

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

photographs. The photographs are taken with olijectives of a
focal length below that of the range of distinct vision, which in
normal sighted people is about ten-and-aquarter inches.
Such a photograph viewed in the ordinary way wonid appear
to 1)0 out of perspective and its parts out of proportion, thougli
.some of this impression could l)e to some extent removed or
remedied by magnifying the photograph.

The accomp.inying figure indicates a method Ii\- which the

Single l-ens Stereoscope, with Photograph.*;.

ej'e can obtain a virtual distance-image magnified of the
photographs. The apparatus will, in the case of normal
vision, bring the different parts of the photograph under the
same visual angles as those obtaining at the moment of photo-
graphic exposure. ,\n achromatic magnifying lens is u.sed,
the focal distance of which is similar to that of the objective
used in photographing the object, and which is free from dis-
tortion for objects situated at i ,', inches from the nearest lens

Fig. 3 (Single Lens Stereoscopy).

surface. The lens (fig. /,) is fiee roni astigmation but not from
curvature of field. Therefore when using it the accommoda-
tion of the eye nnist be altiirc^d accoi'ding as the central part
or the m.irginal part of the photogr;i])hic print isunderinspec-
tion ; and the nature of the eye accouunodadon will v.iry for
short-sighted, long-sighted, and old-sighted people. Hut if all
the directions arc carefully followed, an eye ot normal vision
will j)erceive through tlu'lens, not the photograph as it appears

to the unaided eye, but a far distant im.ige of it, free from dis-
tortion, and under the same conditions of apparent size, dis-
tinctness, perspective, light and sh.ide as those under wliich
the objects themselves would be .seen with the short photo-
graphic objective that has been mentioned. Consei|uently
the small photograph thus conveys to the eye a much more
natural effect than a landscape photograph can possibly do;
and unconsciously the vision forins in the mind a correct per-
ception of relief and dist.mces. Thus although the stereo-
scopic effect is not of the s.ime kind as that produced in ordi-
nary stereoscopes, the effect of solidity- is strongly evident
and perceptible. A.(.i.

"Osprey" Plvimes, Real
and "Artificial."

By W. P. PvcRArx, A.L.S., F.Z.S,, \c.

Without doubt the most beautiful of feather orna-
ments is that commonly known as the " Osprey " plume.
Mow this name came to he used is a mystery, for the
feathers in question are not obtained from the ( Isprey, wliich
is a bird of prey, but from various species of Herons, those
known as " Efjrets " furnishing the most hif^hly prized
varieties. It is from the French form of this word l^gret,
that the term " aigrettes," often used instead of " O.sprey,"
is derived. Naturally, the possibilities of these plumes
as head-dresses, both for men and women, have been
widely appreciated. Only in the Army, however, have
they been worn by men in this country, and the practice
has now been happily abolished. To induce our country-
women to follow this lead, the most strenuous efforts ha\e
been made within recent years to spread a knowledge of
the consequences which follow from the encouragement
of the traffic created by their demands. Though at last
there seems some prospect of success attending these
efforts, unless progress towards tliis end is more rapid, the
extermination of the hapless victims is inevitable.
This in itself would be an end much to be deplored, but
the nameless suffering and pain, which accompanies this
extinction, makes the "passing of the Egret" a pitifully
sad story.

To many women the broad outlines at least of this
matter are already well known, and, as a result, numbers
have decided to leave such ornaments severely alone.
( )thers, unable to break the spell wielded by these seduc-
tive plumes, have compromised, by forswearing what
they believe to be real "Ospreys," and wearing, instead,
what they fondly imagine to be an artificial product.

In purchasing " Ospreys," at least in most milliner's
shops, whene\er scruples are manifested, the assistant
professes to ha\e doubts about the genuineness of tlie
plume, retires to the Manager, and returns, assuring the
anxious customer that a mistake has been made, that,
after all, the plume is artificial. This fact, long known
to the authorities at the British Museum, was shame-
lessly admitted, only a few days ago, by the Manager of
a large shop in London. " But ladies," he remarked,
" arc hard to please, . . . Their consciences have to
he soothed, and the assistant, rather than lose valuable
custom, readily sells the article as artificial ! "

In the wholesale trade the word artificial appears to
ha\ e been used in a technical sense, long before the agita-
tion against the wearing of "Ospreys" began. Inferior
" ( )sprey " plumes and feathers of birds other than Egrets
or their allies, which have been disguised to simulate
" Ospreys," ofe known by the wholesale buyers as
'' iiiiififKih."

Jl-NE, 1904.]

KNOWLEDGE .'t SCIENTIFIC NEWvS.

129

Hut let It bo (Jistiiutiy uiulerstooi.1 that the assertion of
the retail milliners, that the plumes sold hy them as arti-
ficial are made of quills split up, or of whalebone, or of
any other material, are absolutely fiilsr.

The broad facts concerning " Osprey " or " aigrette "
plumes and their origin are briefly these. The " aig-
rettes'" of the milliner are the long, loose, waving plumes
taken from the backs of different species of small 1 leroTis,
the white plumaged species, some ten in number, being
the most \alued. The finest kinds are ttiose from the
Little Egret, Garzetta garzetia, and the Black-footed
Egret, Garzetta iiigripes. In both species the plumage is
pure white, and the long " train" feathers are of a pecu-
liarly loose, flowing type, of great delicacy, and recurved
at the tip. It is this latter peculiarity that gives them
the peculiar value. The little ICgret occurs in Southern
Europe, China, and Japan, S. I!urma, India, Ceylon,
Malay .\rchipelago, and Africa.

Fig. I.- Three plumes of a whte E^rct. G:ir:c:lJ i;nrr.,tl:i, used for the
purpose if making "ospreys" or "aigrettes." Note the extreme
length and slenderness of the "barbs" or thrcad = Iike branches of
the feather.

The black-footed species has a more restricted distri-
bution, being found only in Java, the Molluccas, and
Australia.

A third species, Leucophoyx candidissima, also produces
recurved plumes, but these are not so fine as in the
two just enumerated. This bird occurs in temperate and
tropical America.

In all the species on which this war is waged, some 16
or 17 in number, these feathers are of great length. In
some — e.g., Mesophoyx intermedius — they may attain a
length of 17 inches. From a bundle of such, as many as
four separate plumes could be cut. The delicate ter-
minal portions of the feathers furnish the " genuine
Osprey " of the wholesale trade, and fetch a high price ;
whilst the three lower segments are sold as " artificials "
often at a ridiculously low price — so low that it has often
been contended that they could not on that account be
real feathers. But the tips pay for the whole bundle and
leave a profit ; the lower portions of the feather, there-
fore, may well be sold cheap.

Besides the w'hite Herons — some ten species in all —

llutic aie MjMUil others laid under contribution. These
birds are of varied colours, and the plumes are sold as
" red " or " ash " Ospreys, and so on, as the case may be.
But "artificials" are manufactured, in a sense, by
manipulating the feathers of birds other than Herons, so
as to produce what is at best a crude resemblance to the
real plume. Probably the majority of these are made of
what are known in the trade as " Vultures' " feathers,
which are really the quill or " fiiglU" feathers of the 1\ hea or
South American Ostrich. The method of preparing them
is interesting. The shaft of the fjuill is split down the
centre, so that one half of the "vane" of the feather
adheres to each half of the stem (fig. 3). By spirally
twisting this stem (fig. 4), the barbs forming the right or
left side of the " vane " of the feather are made to form
a series of long, slender filaments spirally arranged
around a central shaft. The efTcct produced, though
graceful, is really quite difTerent to that of the " Osprey"
(fig. i). Moreover, tlie whole plume is hea\ier in
appearance. I'eathers so treated are sold as artificial,
and there is enough truth in the statement to be really

Fi^. 2.— An osprey plume as sold at the milliners. In this case the
plume has been dyed black. It is made up of two portions— a few
valuable tips stuck into a bunch of stumps— i.e., "ligret" plumes,
from which the tips have been removed.

dangerous — dangerous inasmuch as whether sold as
artificial " Ospreys " or as " Vultures' " plumes, the
slaughter of Kheas is encouraged. Indeed, theextinction
of this bird, in a wild state, seems to be rapidly approach-
ing. Annually slain by thousands for the sake of its
feathers, this Rhea has already been extirpated from
much of country it formerly inhabited. That this
should be so is deplorable, for the Rhea is a bird of the
utmost scientific interest and importance.

An equally crude imitation of the real " Osprey " is
made by treating Peacocks' feathers in the same way as
that just described in the case of the Rhea.

But obviously the stump ends of real Egret feathers,
or the split and spirally twisted feathers of the Rhea and
Peacock, cannot he called artificial feathers. But what is
one to do ? some of my readers may ask. How can the
Egret feathers be distinguished from those of the Rhea
or Peacock ? Do not try. Firstly, this is the work of
an expert ; secondly, the sale of the imitation " Osprey "
does but encourage the slaughter of another species. If
the Egret is spared, the Rhea must die.

I30

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

It should be made a punishable offence to sell feathers
under the desi,L,'nation of " artificial," for thereby incal-
culable harm is done, and women are again and again
made parties to a traffic they abhor. True, some do not
care ; but many do. To sell feathers of any kind as
artificial is to obtain money by fraud. A man can no
more be justified for selling as artificial that which is
real, than for selling chalk and water as milk.

To give an idea of the appalling waste of life which the
trade in "Ospreys" is responsible for, we may remark
that in London alone, last year, the produce of 196,000
birds was sold ! As many were probably sold in the
markets of Paris and Berlin, since London no longer has
the monopoly of the feather trade.

1 "g- .?•- Portion of a quill leather of a Rhea, i rorti the left side a large
piece of the stem has been cut. liy twisting this round, the barbs
become i.solated and simulate, crudely, the "osprev" plume. Such
plumes are sold in the shops as "imitation ospreys," or as
"vultures'" feathers.

Unfortunately for the Egrets, these feathers are worn only
during the breeding season, and by both se.xes. As a conse-
(]uencethe slaughter of the adult birds at this time ensures
the death by slow starvation of thousands of young. Really
ihe prosecution of such butchery is devilish ; but what
shall be said of those who, knowing this, yet purchase
these ghastly trophies ? To write temperately on this
aspect of the subject is difficult. The accounts published
by Mr. W. E. U. Scott, an American ornithologist of
the highest standing, are positively sickening. Yet he
purposely refrained from making anything but the
baldest statements of fact ; so much so, that those who
do not know him, as the writer does, might accuse him
of callousness. In his investigations, made in 1886, into
the condition of some of the Bird Rookeries of the Gulf
Coast of Florida, he found that since his last visit, si.x
years previously, whole colonies of birds, numbering in
their palmy days many thousands of individuals, had
been absolutely wiped out by " plume-hunters." These
ghouls travelled in bands of sometimes as many as 60 in

a band. Let me quote two or three passages from his paper
asasample. \'isiting thebreedingplaceof thereddish Egret
in Charlotte Harbour, he writes : " This had evidently
been only a short time before a large rookery. The trees
were full of nests, some of which still contained eggs, and
hundreds of broken eggs strewed the ground everywhere.
. . I found a huge pile of dead, half-decayed birds
lying on the ground, which had apparently been killed
for a day or two. All of them had the ' plumes ' taken
with a patch of skin from the back, and some had the
wingscutoff. . . ." Again: ". . . theexlermina-
tion of a Brown Pelican Rookery . . . is a very fair
example of the atrocities that have been and are still
being committed to obtain ' bird plumes.' . . . One
afternoon, when Johnson (his informant) was absent
from home, hunting, the old Frenchman (A. Lechevallier)
came in with a boat and deliberately killed off the old
birds as they were feeding their young, obtaining about
one hundred and eighty of them. The young, about
three weeks old, to the number of several hundred at
least, and utterly unable to care for themselves in any
way, were simply left to starve to death in their nests, or
eaten by raccoons and buzzards."

One feels sorely tempted to add to this catalogue of
crime if only in the hope that it may stir up some com-
punction in the minds of those directly concerned.
Nowadays, unfortunately, we have become saturated
with a spirit of scepticism, which is nowhere more in-
jurious than in questions of this kind. " But is it not all
horribly exaggerated ? It really can't be true, you know ! "
is the cry of some to whom I have related these horrors.
Others shrug the shoulders and say : "We really must
not be sentimental ; let us set to work, quite dispassion-
ately, and collect evidence." And there they leave the
matter !

Statements have appeared from time to time to the
effect that Egret farms, on the lines of Ostrich farms, have
been started both in Tunis and in America. The Ameri-
can farm was visited some time since, and found to con-
sist of half-a-dozen birds in a small cage in a back yard.
.\ detailed and glowing description was published in a
German paper in 1896 of the success which had attended
the establishment in Tunis. But the statement that the
birds were fed on the carcases of horses, mules, and
donkeys, aroused one's suspicions, and these are con-
firmed by the assurance that the birds are deplumed
i'u'icc a year. The long plumes, as a matter of fact, are
worn only during the breeding season, and therefore the
story of the double crop proves too much. After careful
enquiry, I cannot find that there is a shadow of truth in
any part of the story. But it has caused much mischief,
since plumes have been sold as the product of such
farms.

Buyers of these feathers in milliners' shops are often
told that the feathers are not plucked from the bird at
all, but picked up off the ground. It is probably true
that here and there a moulted feather is picked up in fair
condition, but these can always be recognised by their
soiled state and brittleness. They are useless for decora-
tive purposes. Though normally white, these plumes,
it should be remarked, are often dyed, but that does not
make them " artificial."

From the illustrations to this paper there can be little
difficulty, really, in distmguishing the " Osprey " plume,
taken from the Egret, from the imitation " Osprey " made
of Rhea feathers, or from the feathers of the Peacock.
Undoubtedly, and unfortunately, the Egret plumes are
the more graceful. Were this not so, one might hope to
persuade those w ho consider feather ornaments of this
kind necessary, to adopt the wearing of Rhea feathers, if

June, 1904

KNOWLEDGE & SCIENTIFIC NEWS. Vs^l-d^-^) i

it can be shown that these birds can be farmed at a profit,
as in the case of the Ostrich. So far, however, all en-
deavours to start a new industry of this kind appear to
have ended in failure.

It is to be hoped that even imitation " Ospreys " will
be eschewed in future, until some substitute for real
feathers can be found which will possess the airy •,'race
of the genuine " Osprey," or until they are made of
feathers taken from birds bred for this purpose, or from
some domesticated species. As it is, the good resolution

Hig. 4. -An "imitation o>prey" as sold in milliner's .shop; said to be
made of vultures feather's. It is really made by splitting and
twisting feathers of the Rhea, or South American Ostrich.

to wear only imitation "Ospreys" would create as much
mischief as the wearing of the genuine plume, since the
species called upon to furnish the " imitation " would
themselves sooner or later suffer extermination.

Finally, "Imitation Ospreys" are simply made by
using the feathers of other birds, and up to the present
time these have been of wild birds. The statements
that imitation or artificial Ospreys are made of split
quills, whalebone, or other material, are all absolutely
false.

Electric
Wave MeaLSvirement.

Dr. J. A. Fleming, F.R.S., exhibited at the Royal
Society Soiree a very ingenious and interesting device
for the measurement of electric wave lengths. The
principle of the method will be grasped by anyone who
has watched sea waves impinging against and rebound-
ing from a sea wall. The returning waves sometimes
reinforce and sometimes neutralise the oncoming ones,
so that here we have a wave crest raised above its
fellows, and there a wave neutralised or eliminated. If
the waves were all quite regular, and were uniformly
propelled and reflected, these points of reinforced and
eliminated waves would be fixed. We should in short
have "nodes" and "loops" of force in the train of
waves. Dr. Fleming's apparatus for showing the nodes
and loops of an electric train of waves consisted of a

spiral of fine wire, along which the discharge of two
Leyden jars propelled vibrations varying in number
between a quarter of a million a second. The re-
sultant electric wave travelled along the spiral at about
fifteen hundred miles a second, was reflected and
returned, thus establishing on the wire stationary electric
waves, just as stationary aerial waves are produced in an
organ pipe. The position of the nodes and loops was
ascertained by use of a series of carbonic dioxide vacuum

<rr.

A, B.— Lonji coil of 5,000 turns of

No. .((> wire.
W. liurth wire.
Li, Lj.— l-eyden Jars, each '0014

mfd. capacil>.
X. Variable Inductance Coil, o-2.;o

microhenry's.
I. Induction Coil — lo-inch spark.
S. — Spark balls.

lubes, which glowed when near a loop — the point where
the oncoming and returning waves joined to produce a
region of maximum electric force. Some further details
of the apparatus are as follows : —

The long solenoid of silk covered wire has 5000 turns
and a total length of 643 metres. This solenoid has
parallel to it an adjustable earth wire and a divided scale.
The solenoid is connected to one point on an oscillatory
electric circuit consisting of a couple of Leydens having
a capacity of 0-00068 mid. and an adjustable inductance
of o to 230 microhenrys and a silent discharger. When
oscillations are set up in this circuit by induction coil
discharges, and the fretjuency adjusted, stationary electric
waves are set up in the solenoid.

The position of the first node is always well defined.
Theory indicates that the distance from the end of the
solenoid to the first node should be to the distance
between the first and second nodes in the ratio of 1:2-5,
and that the distance between the first and second nodes
should be half a wave length. Experiments with this
apparatus give a mean value of i : 2-4 for the above ratio
for the first five odd harmonics.

The inductance of the long spiral is 100 microhenrys
per centimetre of length and its capacity is 26 x 10"" of a
microfarad per centimetre of length. From these data
the velocity of the wave along the spiral is found to be
about 196 million centimetres per second.'' From the
wave lengths experimentally determined the correspond-
ing frequencies are then found, and these agree substan-
tially with the frequencies as calculated from the induct-
ance and capacity of the Leyden jar circuit that is
employed. Thus, corresponding to the first odd har-
monic the node is 64 centimetres from the end. The in-
ductance in the jar circuit is then 79 microhenrys, and
the frequency as determined from the node -position and
wave-velocity is 720,000 complete oscillations per second ;
whilst from the jar circuit inductance and capacity it is
690,000, or in fair agreement. The practical interest of
the apparatus lies in the fact that it is in actual use for
measuring the lengths of wireless electric waves such as
are sent out from the station at Poldhu, in Cornwall.

5 X I06

4 /Capacity of Jar in
» microfarads

Frequency

See Dr. Fleming's Cantor Lectures, 1900

Induction of Coil
in c.m.s.

132

KNOWLEDGE & SCIENTIFIC NEWS.

[JlNE, 1904.

The International
Association of
Academies.

The chronicle of scientific movements of the past
month would be incomplete without a record of the meet-
ing in London of the General Assembly of the Inter-
national Association of Academies, an event which
brought together a singularly noteworthy gathering of
men of science and of letters. .\n assemblage of such
cosmopolitan and select character as this was, comprising
the representatives of the premier academies of the world
in the departments of knowledge, had not hitherto been
seen in the metropolis. We have been privileged to
receive and welcome from time to time the various foreign
deputies to the peripatetic meetings of the British Associa-
tion, as well as those attending the meetings of chemical,
medical, and allied learned bodies, but never a congress
of the world's academies. This necessarily stands on a
plane distinct from composite gatherings held under
auspices such as the above mentioned, responsible though
they be in themselves, and worthy of all respect.

The reason lies upon the surface, and is easy to state.
An amalgamation of academies strikes a new note, for it
is based on the wider authority that may be derived from
international co-operation, regularly organised, and made
applicable to the advancement of learning in its broadest
aspects. Here is an effort to open up useful avenues of
knowledge, and break untrodden ground under the stimu-
lating influence of a common purpose. And what of the
need for an organisation possessing these aims and
characteristics ? The answer is that its inception is the
actual and perceptible response to aspirations long enter--
tained by men of science and learning of various countries.
It may be recalled that Sir Michael Foster, at the Dover
meeting of the British Association in 1899, uttered these
weighty words : — " Xo feature of scientific inquiry is more
marked than the dependence of each step forward on other
steps which have been made before. The man of science
cannot sit by himself in his own cave weaving out results
by his own efforts, unaided by others, heedless of what
others have done and are doing. He is but a bit of a great
system, a joint in a great machine, and he can only work
aright when he is in touch with his fellow-workers."

From general considerations of this nature, reference
may pass to the initial steps that led ultimately to
the foundation of what is now denominated the Associa-
tion of Academies. Germany, the home of the greatest
of all academicians, Leibnitz, had zealously fostered for
many years a union of the Eoyal Societies of Gottingen
and Leipsic, in collaboration with the academies of
\ienna and Munich, called a " cartell." This met
annually, turn by turn, at convenient centres for the
purpose of discussing matters of science and learning
in which a partnership of effort was beneficial for the
several ends in view. It so happened that the scheme
of the Royal Society of London (now in active operation)
for the promotion of a universal and continued catalogue
of scientific literature on an international basis was one
of the subjects submitted to the cartell at its meeting at
Gottingen in the year 1S99, at which, it should be
mentioned, English representatives were present by
special invitation. The latter, however, at the time,
had been coupled with the expression of a wish that the
Royal Society would consider the question of itself join-
ing the cartell. To this cordial and significant desire
for an extension of the boundaries of the cartell's sphere

of work — it could mean nothing else — the delegates were
empowered to say that the Society was disposed to join
if the principle of a plan for the founding of an inter-
national combination of the more important societies
and academies of the world was conceded, and, in fact,
made the objective. The little set of foreign academies
agreed, and the next move forward lay in the calling of
a conference at Wiesbaden in the same year, to consider
the general agreement previously arrived at, and to
discuss the lines of establishment of the amalgamation
thus forecasted. Here it is not out of place to recall that
the English delegates on this occasion were Sir .\rthur
Eucker, Professor A. Schuster, and Professor H. E.
Armstrong.

It is beyond the limit of our space to fully detail the
subsequent and steadily progressive history of the move-
ment for an international alliance. Statutes and laws
were, however, formulated, and one by one the adhesion
of the greater societies and academies of the world was
obtained. The appointment of an international council
was ratified, whose duty it should be to conduct the
business of the .Association in the intervals of the tri-
ennial meetings of a plenary General Assembly, such as
that which has just concluded its deliberations. Further,
the decision was taken that the first gathering of the
latter body should be held in Paris in 1901 — an event
which virtually marked the birth of the International
Association. To M. Gaston Darboux, the distinguished
Permanent Secretary and doyoi of the Academy of
Sciences of Paris, fell the privilege of acting as Presi-
dent. By a unanimous vote London was then chosen as
the venue of the next Assembly.

The delegates who have attended the Congress repre-
sented the full complement of constituent academical bodies,
and were drawn from the cities of Amsterdam, Berlin,
Brussels, Budapest, Christiania, Copenhagen, Gottingen,
Leipsic, London, Madrid, ^Munich, Paris, Rome, St.
Petersburg, Stockholm, \'ienna, and Washington. In
the case of London, the Royal Society delegation was
composed of eighteen Fellows, including Sir William
Huggins, its venerable President ; while the British
.Acadrmy, which is now, of course, within the pale of the
Association, was represented by Lord Reay, the Presi-
dent, and six other Academicians. Among notable
foreign men of science and of letters present were the
Count de Franqueville, M. Moissan, Sefior Jose Eche-
garay. President of the Royal Academy of Sciences of
Madrid, Dr. Viktor von Lang, of \ienna. Count Balzani,
and Prof. Svante Arrhenius, the eminent Swedish
chemist.

Among the subjects that have been under consideration
during the Congress may be mentioned a scheme
for carrying on magnetic observations at sea, with the
view of establishing a comprehensive magnetic survey
around a parallel of latitude— a project requiring inter-
national co-operation to be completely successful. Seis-
mological and geodetic investigations were under discus-
sion—domains of inquiry in which scientific men of
various nationalities are just now much interested. The
British Academy promote a scheme for a lexicon of the
Greek language; the Academies of Copenhagen and
Berlin put forward a plan for a Corpus Medicorum .Vnti-
quorum. Then the important question of the establish-
ment of an institute for the purpose of investigating the
anatomy of the brain was under reference — a subject on
which great unanimity prevails among foreign and
English men of science. The above are instanced merely
to indicate a few of the matters of scientific and literary
interest that are before the Association in some stage
or other.

June, 1904 ]

KNOWLEDGE & SCIENTIFIC NEWS.

133

The labours of the plenary Assembly were lif^htened
during the period of meeting by a series of hospitalities
planned by the Royal Society, the Lord Mayor, the
University of London, and a number of representative
men of science ; those carried out by the last-named
being of a particularly cordial and pleasant nature. In
addition, the I'niversities of Oxford and Cambridge
arranged visits, and the conferment of degrees upon cer-
tain of the foreign delegates took place.

REVIEWS OF BOOKS.

Aeronautics. — " My Airships," by A. Santos Dnnioiil (Grant
Richards ; 0/- net), is not a student's book. It is a popular work,
and it does not, even when judj;od by this modest standartl, artord
very much more information than the diiiijent newspaper reader
might have gleaned from thi: files of tlu; daily papers. It is
prolific in anecdotes of M.Santos Dumont's adolesccnce.and it
is charmingly illustrated by photographs of all his tlying
machines and most of his accidents. These photographs arc
indeed the most valuable feature of the volume, and furnish
an idea of tlie evolution of the navigable form of airship,
or balloon. M. Santos Dumont does not furnish any positive
data as to the exact speeds at which he has been al>le
to drive his sliips; but he assumes tliat they travelled at a
higher rate than that which Sir Hiram Maxim, for ex.imple,
thinks that an airship of the balloon type can be driven.
" When, therefore, I state that, according to my best judgment,
the average of my speed through the air in those llighls (llights
with No. 6 in uj02| was between 30 and 35 kilometres (18 and
22 miles) per hour, it will be imderstood that it refers to speed
through the air whether the air be still or moving, and to speed
retarded by the dragging of the guide rope. Putting this ad-
verse influence at the moderate figure of 7 kilometres (4;' miles)
per hour, my speed through the still or moving air would be
between 37 and 42 kilometres (22 and 27 miles an hour)." If
this can be taken .as trustworthy then tliere seems to be
not the slightest reason why M. Santos Duniont should not
" lift " the Grand Prize of S 100,000 which the St. Louis Exposi-
tion is offering for the best average times made over a fifteen-
miles triangular course, provided that the average speed is
not less than i8| miles an hour. Two points are specially to
be noted about M. Santos Dumont's method and the possibilities
he claims for it. One is that he is never foolhardy, and keeps as
close to the ground as he can, since nothing is to be gained by
height. The other is Ih.at he maintains that the chief difficulty
in driving against the wind is not the " push " against the front
of the balloon ship, but the suction or pull at its stern. The
defect of the compilation is chiefly one of omission. One
might well imagine after reading "My Airships" that M.
Santos Dumont alone had done anything worth recording
in the sphere of balloon propulsion, A few allusions are made
to M. Giftard's unproductive experiments of fifty years ago,
but the verj' successful achievements of MM. Reuardand Krebs,
who practically accomplished almcst as much as M. Santos
Dumont has done, are merely referred to as " the trials of
such balloons . . in 1883 had been repeated by two con-
structors in the following year, but had been finally given up in
1885," And yet he says: " Before my experiments succeeded,
were they not called impossible ? " Moreover, no allusions
whatever seem to be made to the Lebaudy balloon, which,
according to all accounts, has surpassed the author's machines
in speed, in distance travelled, and in the number of successful
return trips.

Geology. — Messrs. Blackie and Son have published a fifth
edition, revised, of Mr. Jerome Harrison's "Text-Book ot
Geology." It is an admirably compact text-book in its present
form ; the new photographs arc as welcome as they were
necessary ; and the addition of a table showing the range in
time of invertebrate fossils is extremely and distinctively
useful.

Builders' Quantities — Mr. H. C. Grubb has written " Builders'
Quantities" (Methuen and Co.) with the intention of giving
sufficient and necessary information to technological students
for the City aud Guilds examination on the subject, and to

candidates for the Board of Education examination on Build-
ing Construction. The book is eurincutly practical, and is not
without acute interest for those whose dealings with builders
consist solely in paying their bills.

Radium. " Radimu, and .Ml .M>i>ut It " (Whittakcr aud Co.),
by S. R. Boltone, is a cheap handbook which does not justify
its subsidiary title. It is, none the less, a h.indy suunnary of
the more popularly interesting facts about radium, and it adds
a rather hasty suunnary of some of the theorii-s concerning
radium activities, ending with the doubts cast by Sir W,
liuggins' examination of the spectrum of radium on its final
degradation into helium.

Entropy. Mr. James Swinburne repeats in "luitropy"
(('unstable) those views on thermodynamics which he has
been repeating with consider.ible satislaetiou (o himself both
before and since he read his disturbing paper on the " Re-
versibilily of Thi'rmodynamics " to the Physical Section of the
British .Association last year. Since its publication it has
been denounced by tlie chief opponent of Mr. Swinburne's
views as liki-ly to be extremely disturbing to earnest engineer-
ing students ; but it has at any rate been productive of some
interesting and spirited rejoinders from Professor Perry. As
.in example of Mr. Swinburne's lively style, we may quote the
following passage : "The unit of heat, which is quite an uu-
necess.ary nuisance, has no name, for British thermal unit is
not a name; it is an opprobrious epithet."

"Metal Working," by J. C. Pearson (Jolni Murray; 2s.), is an
admirable guide to the practical manipulation of tools for the
working of metals. Tlie sulijects treated of are divided under
the various headings, such as " l'"iling," " Scraping," " Solder-
ing," " Riveting," iS:c., and each operation is not only clearly
described, but good outline figures and numerous jihotogr.iphs
add greatly to the value of the deseriptioiis, so that any one
mastering this little work may consider himself a fairly expert
metal worker.

BOOK NOTICES.

I Flowering I'lants and Perns. A second edition of the " Manual
and Diction.iry of the Moweriiig Plants and Eerns " (("am-
bridge University Press ; 10s. Od.), wliieh Mr. J. C. Willis origin-
ally wrote in two volumes, has now been pulilished in a single
volume to its great advantage in accessibility of information
.and general usefulness. Mr. Willis's work, modest in aim,
and described by its author as a mere coir.pilation, is of en-
cyclopjedic value to the student of botany. As in the first
edition, its staple contents are a dictionary in which the whole
of the families and the important genera of flowering plants
are dealt with ; and this general information is supplemented
by special treatment in Part I. of the morphology, natural
history classification, geographical disposition, and economic
uses of the flowering plants and ferns. To the new edition
has been added a mass of additional material; and new
features are the articles on outfit, on collecting and preserving
material, on observing and recording, and on general field
work — a method of botanising which receives too little .itteii-
tion. We cannot pay the wi)rk a higher compliment than that
of saying that Mr. Willis's expressed aim " to render the work
sufficiently complete forthe requirementsof botanical students,
schoolmasters, travellers, residents in outlying districts, and
the considerable class of ])eople who have an indirect interest
in botany, and need some general work of reference on that
subject . . ." has been completely and triumphantly at-
tained. At the same time the student at home will l)e able to
make constant use of it as a treatise of reference in general
morphology and geology on plant distribution and systematic
botany.

War in tiie Far East, - W'e have received from Messrs, Virtue
and Co. for review the first volume of a history of the Russo-
Japanese War, "War in the P"ar East," by E. Sliarpe (Irew.
Vol. 1, which is attractively bound and illustrated, deals with
the preliminary history which led to the outbreak of war. The
evolution of Modern Japan is traced ; the relations of Japan
with Korea and China are described, .and an account is given
of the Chino-Japanese War. It is shown how the interven-
tion of luiropean Powers in the settlement of Peace negotia-
tions and the sub.sequent Russian encroachments led inevitably
to the present crisis in the P'ar East.

134

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

Conducted by F. Shillington Scales, f.r.m.s.

MITES.

Cecil Warburton, M.A.

(Coniinucd from page 105.)
Akp now, perhaps, a somewhat more detailed account
of the animals we are looking for may not be out of place.
That they are not insects, but arachnids, is doubtless
perfectly well known to readers of " Kxowledge." They
are without antenns, and have normally eight legs when
mature. The_ Oribatida are blind, but when eyes do
occur in the mite tribe they are simple and not compound.
The Arachnida of this country are represented by the
spiders, the harvestmen, the " false-scorpions," and the
mites. The false-scorpions, or Chelifers, are unmistak-
able, and the spiders are distinguishable at a glance from
the mites because of the narrow pedicle or "waist " which
joins the two portions of their body. The characters
which separate the mites from the harvestmen are not
quite so obvious, but the latter have the abdomen more
or less distinctly segmented, and have always two eyes
on a turret in the middle of the fore-part of the body. In
practice there is little danger of confusing the two groups,
as very few mites, except the easily recognised ticks, are
equal in size to the smallest British Phalangids or har-
vestmen. All mites live on fluid nutriment, some deriv-
ing it from animals, others from plants, and their mouth
parts are accordingly adapted for piercing and sucking.
It will be useful, perhaps, to give in this place a short
review of the principal acarine groups, and to indicate in
a few words the general condition of our knowledge with
regard to them.

First of all, then, we have two families of very minute
worm-like mites, the Eriophyidre (or Phytoptida-) and
the r)emodicida\ The former are generally known as
gall-mites, and are responsible for various plant diseases,
a familiar example being the disease of " big bud " in
black currants, which is caused by Eriophyes rihis. The
Demodicidae are animal parasites, and the best-known
example is Demode.x foUiciiloriim, parasitic in the hair
follicles of man. Then follow the Sarcoptidre, or itch-
mites, extremely unattractive creatures, which are external
parasites of various vertebrate animals. All the above,
possessing a certain economic importance, have neces-
sarily attracted more or less attention from those who
study the diseases of animals and vegetables, but from the
faunistic point of view there is much ignorance with re-
gard to them in this country. For further information
we may refer the reader to Neumann's " Parasites of
Domesticated Animals," which has been translated by
Dr. Fleming, and to Connold's handsome volume on
" British \'egetable Galls."

We next come to the Cheese-mite tribe or Tyrogly-
phids, which feed chiefly on decaying animal or vegetable
matter. They are a small group of soft-bodied mites,
generally white in colour, and the British species have
recently been monographed by Michael in the publica-
cations of the Ray Society. Then follow the Oribatids,
with which we are pnncipally concerned in the present

paper, and they are succeeded by the ticks or Ixodidae.
Though their comparatively large size has probably made
the ticks the most familiar examples of mites to the
uninitiated, yet we are only beginning to know some-
thing ^.bout them, and recent investigations in their
direction are again entirely due to their economic impor-
tance as the medium by which various dread diseases are
communicated to man and domestic animals — chiefly in
foreign countries. Neumann's " Parasites " may again
be consulted, and the same author has written a Revision
of the Ixodida;, but the British ticks are only very
slightly known.

The same may be said of the Gamasida?, free-living
predaceous mites, examples of which are sure to be found
among the moss in which we are seeking the beetle
mites. They run rather quickly and use their long front
legs chiefly as feelers. A serious attempt to deal with
the British species is very much to be desired.

Other families of free-living mites, also clamouring for
attention, are the Bdlellida? or snouted-mites, and the
Hydrachnida' or fresh-water mites, and then we come
to the Trombidiida?, which include the velvety scarlet
" harvest mites," and the Tetranychidre or spinning
mites, a familiar example of which is the " red spider,"
so obnoxious to fruit growers. Almost the only English
work which professes to deal with these groups is Murray's
British Museum hand-book entitled " Economic Insects
— Aptera," a book necessarily long out of date, and not
free from grave errors. It is abundantly clear, therefore,
that much remains to be learnt with regard to the British
Acari, some families of which are practically untouched
by any recent investigator.

And now for a few final words concerning the Oriba-
tida8, which afford in many respects the best introduction
to the study of the mite tribe. Four stages are distin-
guishable in the life-history of these mites — egg, larva,
nymph, and imago. In some species the transformation
or metamorphosis is very complete, there being hardly
any resemblance between the nymph and the imago,
while in others the change is not so striking. The eggs
are relatively very large, and the larva; which hatch out
may be recognised as such by the fact that they possess
only six legs. The fully-grown creatures are generally
slow moving, and with hard or leathery integuments.
Their body is usually pretty clearly marked off into two
regions, the cephalothorax and abdomen, though only in
one genus, Hoploderma, are these capable of independent
movement. Whether a mite is an oribadid or not may
be readily determined by examining the cephalothorax,
for in this family there is always present a pair of curious
sense organs known as pseiidosiigniatic ovf^atis. They are
modified hairs, of varying shape, proceeding from the
centre of two circular pits with raised edges situated near
the sides of the hind part of the fore-body, near the com-
mencement of the abdomen. Their peculiar shape and
disposition are of prime importance in determining the
species of one of these creatures. In the nymplis the
legs always terminate in a single claw, but the images
may be either monodactyle or tridactyle. The nymphs
moult three times before the mature stage is reached, but
in some cases the cast skins are never entirely thrown off,
and the adult mite walks along with the three nymphal
skins still adhering to its back.

These mites differ very much in the general appear-
ance they present, some being smooth, glossy, and beetle-
like, while others have a rugged, leathery appearance
and are furnished with warty prominences, or bristle with
hairs and spines. Some of the more hairy species have
a remarkable habit which is a distinct nuisance to the
collector. They cover themselves — doubtless for pro-

June, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

135

tective reasons — with particles of dirt, which entirely
alter their appearance, and are by no means easy to
remove completely, and these grotesque moving particles
of dust and lUbris have to undergo very rigorous ablutions
before they are ready for the cabinet.

Roya-l Microscopical Society.

April 20. — Dr. Hy. Woodward, F.K.S., Vice-President, in
the chair. A large tank microscope, ni.ide by Thomas Ross,
presented to the Society by the Committee of the Qiiekctt
Microscopical Club, was exhibited. It was made not later
than the year 1S70, and was dcsisiied for the purpose of
examining objects contained in aquaria. It was a beautifully
made and highly-finished instrument, having nearly every
conceivable adjustment. The annual exhibition of Pond-Life
was given this evening by Fellows of the Society, assisted by
members of the Onekctt Microscopical Club.

Quekett Microscopical Club.

The 4ijth ordiu.ary meeting of the Club was held on
April 15, at 20. Hanover Square, W. — the President, Dr. K. J.
Spitta, V.P.R..-\.S., in the chair. A paper was read by Mr. W.
Wesehe, F.K.M.S., " On some new Sense-organs in the Diptera."
The paper was well illustrated by diagrams and drawings.
After briefly reviewing the investigations of Packard, Flatten,
Forel, Lubbock, and others into the senses of taste, smell, and
hearing in insects, the author proceeded to show that he had
found processes homologous with the " taste-hairs " of Krae-
peUn in some Orthoptcra, Coleoptera, Diptera. and Hymenop-
tera. Organs were then figined on the antenna; of Gastro-
philusctjui, L., Stratiomys chamckoii . L., and Bihio hoiinlnniis. L.,
which were thought to be typical olfactory organs. Both the
antenn<E and palpi of insects were considered capable of re-
ceiving the stimulus of several senses, but their capacities
differed so much in various genera and species that a general
rule could not be formulated. The author had found new sense
organs on the femora of maTiy Diptera which he was unable to
assign to any sense of which we have conception. Other
organs of quite different construction had been found on the
libias of some minute Fmpid;e. Their functions were quite
unknown, and several experiments which had been made with
a ^ew of discovering the functions had yielded only negative
results.

Journal of the Quekett Club.

The April number of this Journal, wliich has just reached
me, contains sever.al useful articles and notes, amongst which
are a note by Mr. F. J. Cheshire concerning Abbe's test for
aplanatism, and a simple apertometer derived therefrom, the
apertometer being figured on a separate plate, so that it can be
cut out and used on the microscope in the way described by
the author. Mr. F. P. Smith, the new Editor of the Journal,
contributes a note on the spiders of the subfamily Erigoninse;
Mr. Rheinberg a note on an overlooked point concerning the
resolving power of the microscope ; and Mr. Scourfield con-
cludes his synopsis of the British fresh-water Entomostraca,
including the Ostracoda, Phyllopoda, and Brancliiura.

Microscopic Slides.

In the advertisement columns of this magazine will be
found a notice relating to the sale of duplicates of slides from
the collection of Mr. J. Hornell, of Jersey. Many of my
readers will be familiar with these beautiful preparations,
which include botanical as well as zoological subjects, and as
they are now being dispersed, and are offered at quite nominal
prices, I have felt myself justified in calling attention to
them.

Practical Botany and Geology Classes.

I have been much interested in receiving from Mr. J. M. li-
Taylor, Curator of the Free Museum at Paisley, particulars of
field rambles held in that neighbourhood from .'\pril till the
close of the public schools in July, with a view to giving
students a practical acquaintance with nature. The plan is
excellent, and well worth being taken up by other of our many
Free Libraries. Excursions are held twice 1 week, namely

on Wednesdays and Fridays, leaving Paisley at 5.40 p.m., or
such other time as may be agreed upon, many of the excur-
sions being in brakes so as to get well into the surrounding
country. For the last five or six years during each session the
class has brought in from its field rambles the typical wild
plants, grasses, ferns, &c., of the time and district, and these
have been placed on view in the Free Museum with their
English ancl scientific names attached. Fresh specimens of
plants were added twice weekly, and lists thereof published in
one of the local daily papers. Nature knowledge was studied
practically at these excursions with the help of the camera, a
portable microscope, and a dredge for streams and ponds. At
the New Year a four days' exhibition was also held. By the
kindness of a local lady, Mrs. Poison, of Lcven Castle, prizes
of microscopes were offered to the members of the class for
the best collection of dried, mounted, and named wild plants,
grasses, and ferns ; aiul a microscope was likewise offered to
working men and women who would also make a dried collec-
tion, with names (which were obtained from specimens shown
in the Museum), but who were not members of any class or
Natural History Society, where names of plants were given.
This prize was gained by an ex-mason. For members of the
class each collection had to contain 400 specimens; and for
the collection made by working men and women there must
be 200 specimens. It is to be hoped that so excellent a scheme
mav find manv imitators.

Notes and Qvieries.

Chrysanthemum Fungu8. (C.H.C.)

I have submitted the chrysanthemum leaves to Miss
E. M. Gibson, who has for some time been investigating this
fungus in tlie Cambridge i;niv('rsity Botanical Laboratories.
I learn from her that it is quite a new species, having only
been discovered some six or seven years ago, and has been
described, as far as present knowledge allows, by Dr. Ernst
Jacky, in the Zcitschrift f. Pflaur.cii-Krankhcitin, Vol. X. (ujoo).
It has been tentatively named " Uredo-chrysanthemi," but
though Mr. Massee, in the Gardener' a Chronicle speaks of other
stages teleuto or aecidio spores have not hitherto been
definitely found, or at least the evidence is not complete.
Miss Gibson says she has herself quite failed to find any other
stage than the nrcdo spores, as on the leaf you sent me.
Apparently the fungus, though unquestionably injurious, is not
necessarily destructive to the plants, but various species living
under similar conditions, show a curious variation in suscepti-
bility to attack, especially under high cultivation. .So far the
conditions favourable or otherwise to the fungus have also
not been determined.

Making Rock Sections.

Mr. C. H. Caffyn, of Hornsey, writes with regard to rock
sections: " I tried to make sections, as recommended in the
text-books, with emery powder on a piece of zinc or glass, but
it was a very long jol), and the results wore not altogether satis-
factory, and were quite out of proportion to the time employed.
I then thought it could perhaps be done with ordinary emery
cloth, and I find this does very well, and takes much less time.
I first chip off .as thin a flake as possible, and grind one side
flat on ' F ' emery cloth. Then I use No. i and then No. o,
and then polish on a piece of No. o that has been rubbed
down with a bit of itself to take the surface off. The piece of
rock is then stuck on a bit of plate glass with ordinary mucil-
age—I use Stephen's gum. When dry, the rock can be rubbed
down as mentioned above. Great care must be taken when
rubbing on the No. o to finish, as the section is apt to crumble
at the edges. When it is thin enough (which I generally judge
by reading print through it), put the piece of glass and section
in ordinary water till the section floats off the glass. Then
wash with a sable brush to remove all gum. Soak in methy-
lated spirit to remove water. Evaporate spirit, soak in ben-
zene, and mount in balsam and benzole." Mr. Caffyn has
sent me some slides to look at which have been made in this
way, and which seem quite equal to those made by the
ordinary process.

[Communicationi and ciKiuiyies on Microuopical mailers are invileU,
ami should he addressed la F. SliillhigUm Scales, ■■ Jersey," SI.
Barnabas Road, Cambridge. \

136

KNOWLEDGE & SCIENTIFIC NEWS.

[June, 1904.

The Face of the Sky for
June.

By \V. Shackleton, F.R.A.S.

The Sun. — On the ist the Sun rises at 3.51, and sets
at 8.5 ; on the 30th he rises at 348, and sets at 8.18.

The sun enters the sign of Cancer on the 21st at 9 p.m.,
when summer commences.

The equation of time is negligible on the 14th.

Sunspots have been very conspicuous of late, whilst in
addition spectroscopic observations of the Sun's hmb have
shown many fine prominences.

The positions of the spots with respect to the equator
and a.\is may be derived from the following table : —

On the 1st Saturn rises about midnight, and on the
30th about 10.15 P-™- The northern surface of the ring
plane is presented to us.

Uranus is in opposition on the 19th, hence about this
date he is on the meridian at midnight. The apparent
diameter of the planet is 4". In consequence of his low
altitude, it is rather difficult to see the planet with the
naked eye, but any slight optical aid renders him easily
visible. The appended chart shows his position in
Sagittarius.

Date.

Axis inclined to W. from
N point.

Centre of disc, N of
Sun's equator.

June 5 ..
.. 15 ■■
.. 25 ..

13° 54'
9''45'

5= 21'

0° 3'
1° 15'
2° 25'

The Moon :-

Date.

Phases.

H. M.

June 6 . .

., 13 •■

20 . .

,. 27 ..

([ Last Quarter
• New Moon
5 First Quarter
0 Full Moon

5 53 a.m.
9 II p.m.
3 II p.m.
S 25 p.m.

Occulta-tions.

The particulars of the only occultation likely to be
observed during the month are as follows : —

Date.

Star's Name.

June 24

Magni-
tude.

Disappear-
ance.

Reappear-
ance.

d Librae

43 I 11.55 pm. 10 30 a.m. (25th)

The Planets. — Mercury is a morning star in Taurus,
he is at greatest westlerly elongation on the 8th, when
he rises about an hour in advance of the sun.

Venus is a morning star, but too near the Sun for
observation.

Mars is in conjunction with \'enus on the 19th, and
therefore also out of range.

Ceres. — The minor planet Ceres is in opposition on
the 5th, when the magnitude is 7-4. On this date the
asteroid has the same declination as the star 4 Ophiuchi
but is oh 1 8m 41s west of the star.

Jupiter is a morning star, rising about i a.m. near the
middle of the month.

Saturn is in the eastern portion of Capricornus near
the star 3 ; the planet is at the stationary point on the
1st, after which date his motion is retrograde.

Path ok Uranu.s in Sagittarius : —

Neptune is in conjunction with the Sun on the 27th,
and consequently is unobservable.

Comet a 1904. About the middle of April the first
comet of the year was discovered in Hercules by Brooks,
at Geneva, N.Y., U.S.A. It is a faint telescopic object,
diminishing in brightness, and is slowly moving along
the borders of Draco into Ursa Major. Early in June,
it should be near the star i Ursae Majoris.

The Stars : —

Positions of the stars about lo p.m. : —
Great Bear, Cor Caroli.
Ursa Minor, Cepheus, Cassiopeia.
Lyra, .Vquila, Saggittarius, Cygnus.
Hercules, Ophiuchus, Corona, Libra,

Zenith
North
East
South

Scorpio.
West

~N.\V.

-S.W. : \'irgo and Bootes.

Quadruple star.
The star can be
(mags. 4-6, 4-5:

Leo, Cancer.-
: Capelhi.

Telescopic Objects: —

Double Stars: — ,3 Scorpii, XM-i^o™, S. 19' ^i', mags.
2-0, 4-0; separation i3"-i.

( Lyra-, XVIII." 41'", N.39'^ 32'.
better known as the " double-double.'
divided into two components «' and
separation 207") with the slightest optical aid and under
favourable conditions the naked eye alone is able to
effect separation; using a power of about 150 on a 3 or
4-inch telescope, each of these can again be divided, t^
mags. 47, 6-3 ; separation 3"-o; f'^ 4-9, 5-2, 2"-^.

f Lyrre, XVHI." 41'", N. 37° 30', mags. 4-3, 5-9;
separation 44". \'ery easy double ; power 20.

i Lyra', .XVni.''5i'", N. 36" 49 ', mags. 5-5, 5-9; naked
eye double. Glorious field for low powers (I Ff 66).

S Serpentis, XX'III.'" 51'", N. 4^ 4', mags. 3-9, 4-2;
separation 22". Fine pair in small telescopes.

Clusters and Nebula-. — M80 (Scorpio). A compact
globular cluster half way between a and 3 Scorpii ; looks
like a nebula in small telescopes.

M57 (Ring Nebula in Lyra). Easily found by setting
the telescope J of the distance from jS towards y. Rather
faint object, but readily seen as a small ring in a 3-inch ;
it is the only annular nebula visible in small telescopes.

KDomledge & SeieDdf le Nettis

A MONTHLY JOURNAL OF SCIENCE.

Conducted by MAJOR B. BADEN-POWELL and E. S. GREW, M.A.

Vol. I. No. 6.

[new series.]

JULY, 1904.

r Entered at "1
I Stationers' Hall. J

SIXPENCE.

j Contents and Notices. See Page VII.

Flower Mimics acnd
Allviring Resemblance.

By Percy Collins.

Not the least curious insects which gain protection from
their enemies by means of a likeness to surrounding
objects are those which may be described as flower
mimics. Of these, some remarkable instances have
already been described, nor is it unlikely that others,
equally striking, remain to be discovered. Among
butterflies, one may often trace a likeness between the
resting insect and the buds or blooms amongst which it
has settled. This flower resemblance is seen in the case
of our common "white" butterflies, which, when settled
among such blossoms as those of the pea tribe, have an

n'liiMgf -m^

Group of Orange-tip Butterflies and Cow Parsley.

undeniable general likeness to the unopened flowers.
Again, a contributor to the Speaker recently pointed out
the resemblance of the resting " wood white " butterfly
{Leucophasia sinapis) to the flower buds of the corn
wheat — a plant invariably abundant in the woods fre-
quented by this dainty insect. The present writer is

able to substantiate this ohservalion, being familiar with
one of the few remaining dij;tricts wherein the " wood
white " is still fairly common.

A more specialised case of tloral simulation is seen in
the " orange-tip " butterfly {Eiuhloc mi'dinniiii-s), aninscct
familiar to all lovers of the outdoor world, 'i'he upper
surface of this butterfly's wings are white marked with

A Species of Fl^ilit from Perak. (Somewhat enlarged.)

black, with (in the male only) two large orange areas in
the fore wings. The colouring of the underside, which
is identical in both se.xes, seems designed in imitation of
a small truss of the tiny white florets of some umbellifer-
ous plant, such as the hedge parsley. Such pale or
white flower masses are among the commonest blossoms
of the hedgerow in the springtime, when the "orange-tip "
butterflies are on the wing. It is, of course, extremely
doubtful whether the butterflies have any knowledge of
their protective colouring ; nor is there any ground for
supposing that the insects select the neighbourhood of
umbelliferous blooms as resting places. At the same
time, it seems quite admissible to suppose that the colour
likeness of E. aiyduiiniies to florescence common in spots
frequented by the insect is likely to stand it in good stead
as a protective disguise. The underside of the hind
wings, between which the fore wings are folded when
the insect is at rest, are mottled white and green — the
white patches resembling tiny florets, while the green
represents the background of vegetation against which
they are supposed to be seen. Those who have not ob-
served the " orange tip " butterfly in nature may judge
of the closeness of the protective resemblance by a glance
at the accompanying photograph.

Several of our common " blue " butterflies have wings
mottled and spotted on the under surfaces in a manner
which suggests the plantain heads and grass flowers
amon'r which these insects are accustomed to rest. And

138

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

as these butterflies are accustomed to go to roost long
before twilight has settled in, it is quite likely that their
shape and colouring protect them from the attacks of
birds.

Perhaps the most curious case of protective flower
resemblance is that vouched for by Professor Ciregory,

Individuals of a Species of I'Uila grouped upon a Plant Stem. Note
flower-like appearance.

and described in his work, " The Great Rift \'alley."
The insect in question is a species of Flata, which is a
genus allied to the scale-msects, and to the Apliida.
The species described by Professor Gregory is indigenous
to British East .Africa, and is dimorphic — a certain
number of indixiduals of each sex being bright pink in

colour, while others are bright green. These insects
resemble the green fly, or Aphida, in habits, sitting
motionless on plant stems for long periods and feeding
upon the sap. The manner in which the individuals of
the present species are said to group themselves is very

W'j^w^Sk 'j2K

MhBJ^^

^^^^ ' ^^fll^Htd!^^BI&

-,m i

;_^i,^

A green Mantid, from Ceylon, lying in wait among foliage.

Brown Mantid. from Usambava, at rest on bark.

remarkable. The pink ones sit upon the lower part of
the stem, while the green ones have their place above,
towards the extremity. Further, the developing larvae,
which secrete long filaments of a waxy substance, and
are quaint, fluffy little objects, sit beneath the pink indi-
viduals at the lowest part of the stem. Thus, the exact
appearance of a spiked inflorescence is simulated.
The fluffy larvre have a distinct likeness to seed
poJs. Tiie pink individuals might be mistaken
for drooping flowers, while the green ones, higher
up the stem, look like so many undeveloped
buds. Professor Poulton, however, has re-
marked that the grouping of green and pink
insects in Professor Gregory's observation was
probably accidental.

So far, we ha\ e examined only instances of
protective resemblance — instances, that is to
say, in which the colours, or the colours and
form, of an insect are seen to be of value to it as
a means of escaping detection. W'e have now
to consider cases in which the appearances of
insects, while possibly screening them from
the attacks of their enemies, have the additional
advantage of enabling them to approach un-
observed the creatures upon which they them-
selves prey. Such instances of resemblance
may be termed aggressive.

The curious "praying insects," or Mantidie,
afford many striking examples of aggressive
resemblance. The whole of this large family
is insectivorous in habit, and the majority of

Jl'LV, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

the species are either green or brown in colour. So that
when sitting motionless among foliage, or upon the bark
of trees, they are not only inconspicuous to such
enemies as birds and lizards, but are also hidden from
the small insects which form, in the main, their food.
The MantidcE are almost all sluggish in their move-

Another view of same insect.

ments, seeming to be aware that the needs of their life
will be best served by tranquillity, rather than by effort.
They sit motionless in the sunshine — brown species upon
bark, green species amongst foliage — and wait. At most
their activity consists in a stealthy stalking among the
leaves until they come within striking distance of their
victims. The first pair of legs in Mauiida is useless for

I spci u's, liDwever, have been described. 'i"he colours may
be restricted to a certain area or may suffuse the whole
surface of the insect. And when these insects assume
I their characteristic attitudes amongst vegetation, these
! colours often give them a curiously flower-like aspect.
t Now, it is well known that highly specialised flowers rely
mainly upon the aid of insects to secure cross-
fertilisation, and that honey is secreted as a
bait to attract the winged visitors. It has,
moreover, been demonstrated that the colours
and markings of flowers attract honey-gathering
insects. Hearing these facts in mind, it is not
dilficult to realise that a quaintly shaped and
brightly coloured Mantis, hanging motionless
fiinong green foliage, might, at times, be
mistaken by other insects for a flower. That
such mistakes actually occur has been vouched
for by several observers.

Dr. Wallace mentions an insect {Ilymciwpiis

liiconiis), discovered by Mr. Wood JViason,

which attracts insects to their destruction by

its flower-like shape and pink or white colour.

Parts of the insect's legs are so flattened as to

simulate the petals of the supposed flower. In

this instance, the whole of the Mantis looks

like an orchid, but in the case of Itloliiim

diabolicum, from Mozambique, a drawing of

which is exhibited in the Natural History

Museum at South Kensington, only the under

surface of the thorax and fore-limbs have a flower-like

colour and form. The body, wings, and hind legs are

greenish or brown, in harmony with the foliage by which

they are partially hidden when the insect is lying in wait

for a meal.

Perhaps the most authentic instance of alluring resem-
blance is that described on the authority of Dr. J. Ander-
son. The Mantis is Gongylus gongyloides from Southern

Raptorial Limbs of a Typical Mantid.

walking, but is wonderfully modified to serve as
"clappers" for seizing prey. In the use of these limbs
the insects are very rapid and dexterous, not only cap-
turing insects which have settled upon a leaf, but even
grasping them when actually on the wing. The rows of
sharp spines with which the modified femur and tibia are
armed make it impossible for the prey to escape when
once the Mantis has seized it.

It has been said that most of the Maniida are either
green or brown in colour. A few brightly-coloured

c;fH(y2(/»s (/w«/,'i//on'''s, from Southern India.

140

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

India — a species which has been known to naturalists for
upwards of three centuries, but of whose strange habits
nothing was discovered until comparatively recent years.
Living examples of Goiigylus have been thus described :"
" On looking at the insects from above they did not
exhibit any very striking features beyond the leaf-like

Prothorax, Raptorial Limbs and Head of G. Onnniiloidrif in Fiower=
mimicking pose. The insect is hanging head downwards.

expansions of the prothorax and the foliaceous append"
ages of the limbs, both of which, like the upper surface
of the insect, are coloured green, but on turning to the
under surface the aspect is entirely different. The leaf-
like expansion of the prothorax, instead of being green.
is a clear, pale lavender-violet, with a faint pink bloom

G. <;on;(j i„i /«, as above. Raptorial Limbs expanded to seize prey.

along the edges of the leaf, so that this portion of the
insect has the exact appearance of the corolla of a plant,
a floral simulation which is perfected by the presence of
a dark, blackish-brown dot in the centre, over the pro-
thorax, and which mimics the opening to the tube of a
corolla. A favourite position of the insect is to hang
head downwards among a mass of green foliage, and,
when it does so, it generally remains almost motionless,

• Pro. Asiat. Soc. Bengal, 1S77, p. 193.

but, at intervals, evinces a swaying movement as of a
flower touched by a gentle breeze ; and while in this
attitude, with its fore-limbs banded violet and black, and
drawn up in front of the centre of the corolla, the simula-
tion of a papilionaceous flower is complete. The object
of the bright colouring of the under surface of the pro-
thoracic expansion is evident, its purpose being to act as
a decoy to insects, which, mistaking it for a corolla, fly
directly into the expectant, sabre-like, raptorial arms of
the simulator."

_.*-

Houlk

■/;'

-■ /

fe)

y^aaTMO^MA

Z:^ Troe Am. ntCr.

x,^

^^ TiItlo.

G, Gor.ni/: ^:'h\'. Key Diagram of Prothorax. Raptorial Limbs and
Head; and Ventral .Surface: Insect hanging head downwards.

A more perfect combination of protective and alluring
resemblance than the above could hardly be conceived.
The green colouring of the body and legs of the Goiigylus
harmonises with the foliage amongst which it rests, and
affords an effective hiding from the sharp eyes of insecti-
vorous birds. The unusual shape and brightly-coloured
under side of its prothorax and fore-limbs constitute a
lure, by means of which the Mantis attracts to itself the
smaller insects upon which it feeds.

Colour-PaLttern in Beetles.

In \'o1. X. of the Decennial Publications of the Chicago
University, United States, \V. L. Tower gives the results of his
study of the development of colour and colour-pattern in
beetles and other insects. The colours of insects are of two
kinds. On the one hand, there is the dermal or typo-dermal
coloration, coeval with the group itself, and disposed in spots
and strips correlated with the underlying vital organs. On
the other hand, there is the coloration produced by scales or
modified hairs, which is of much later origin. The latter type
of colouring is solely ornamental, its development has had no
relation to the vital organs, and is, consequently, much more
diverse than the original colouring, which it tends to obscure.
.•\ good example of the difference between these two types of
colouring may be observed in the contrast between the dull
browns and yellows of the ground-beetles of the Catabus
genus, and the gay colouring of the Vanessa group of butter-
flies. Dermal colouring begins in the fore part of the body,
where the muscles first harden, and thence spreads to the
back. It is obviously concerned with the hardening of the
Cuticula, which has a tendency to turn brown, a fact which
accounts for the predominance of browns and yellows common
in beetles and cockroaches.

Jii.v. 1004.

KNOWLEDGE c<t SCIENTIFIC NEWS.

The Inflvience of
Fvingi

For Good on OtKer Forms of Life.

Geo. Massee, F.L.S.

In discussing- the various phases included under the
subject of the influence of fungi as fa\ouring, either
directly or indirectly, the welfare of other forms of life,
in the order of their relative importance, the first to
claim attention is that of fung-j pla)ing the part of
vegetable scavengers.

When bread, cheese, or other organic substances be-
come muddy or mildewed, the general opinion is thai
a certain amount of decay has taken place, and therefore
mildew appeared as a consequence of such preliminary
decay. This idea, however, is not correct, the mould or
mildew being the original cause of decay, or change ol
composition of the body attacked. The spores of fungi
are always present in large quantities in the air, and
consequently alight on everything not specially pro-
tected. The reason why mouldy food is not universal,
seeing that it is so much exposed to the air, is due to the
fact that fungus spores can only germinate, and produce
a vigorous mycelium, under certain well-defined condi-
tions as to temperature, moisture, and the supply ol
proper food in an available form. The conditions under
which fungi can grow most vigorously varies for every
kind. Taking temperature, there is a maximum and
minimum of heat, above or below which the spores can-
not germinate, hence no growth takes place ; some-
where between these two extremes there is an optimum
point, at which the spores germinate and form the most
vigorous mycelium, provided other conditions are also
favourable.

Cold storage, whether practised in the primitive
manner of placing- cooked food in a cool place ; the
freezing of raw meat; or the storing of ripe fruit in a
cool room for preservation, simply means keeping the
substance at a temperature below the minimum point at
which the spores of the fungus or bacterium known to
attack such substance can germinate.

No fungus spore can germinate in the absence of
moisture. Again there may be too much or too little
water for very robust growth, and in the case of
heat, there is an optimum or best proportion under
which growth proceeds most actively.

Some few fungi, as the common blue-green mould
{PeniciUium glaucum), and the grey mould (Bolrylis
ciiierea), show little or no discrimination in the choice of
food, and may appear on almost every kind of dead or
decomposed plant remains, and also on many animal
products. The majority of fungi are, however, very
fastidious in the selection of their food, numerous para-
sitic species being confined to one particular kind of
host-plant ; whereiis some fungi have carried this selec-
tive power to such an extreme as to l>e actually limited
to one particular variety of a species for their food
supply.

As scavengers the fungi mostly exercise their in-

lluonco on mcml>crs of the vegetable kingtlom. Leaving
for future consideralion the ha\()C. wrought by parasitic
lungi on perfectly healthy and vigorous plants, we have
slill left a very large number known as suprop/iytcs, a
term which includes all fungi tliat obtain their liuxl
from dead organic matter.

When leaves fall in the autumn, or dead br;uiches
fall to the ground, or even when whole trees arc blown
down, the current opinion is that they decay as a matter
of course ; but no one who has not studied the matter
can realise the influence exercised by fungi in hastening
their decay, and the compar.itivcly rapid conversion of
such dead substances into water, ga.ses, and soluble

I. "Horn of Plenty" {I'vih yilh'S ro)tiucoi.iui'U>^}', Nat. size.
An edible funjcus.

salts, which can again at once bo utilised as food by
other plants.

It is almost impossible to examine any twig or le.af
that has been lying for some time on the ground, with-
out detecting tlio presence of fungi, either under the
lornii of mycelium in the tissues, when, examined under
the microsco'pe, or as fruit in the form of .-i toadstool,
etc., on the surface. Now these fungi have fed on the
twig or leaf — in other words, have converted part of it
into a toadstool. 'I"he latter soon perishes in turn and
becomes converted into water, saJts, etc., as stated
above. This condition of things continues until the leaf
or twig becomes thoroughly disintegrated and crumbles

142

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

to powder, forming' humus in wliich other plants can
grow and find food.

Finally, fungi are responsible for the hollow trunks of
trees. The fungus first gains an entrance into the tissue
of the trunk tlirough the end of a broken branch, care-
less pruning, the hole made by a woodpecker, or some
other accidental wound. Once in the tissues the mycelium
spreads quickly, and in the course of time the heart-wood
is rendered brittle, and eventually becomes resolved to
powder, wliicli is removed by wind ;md rain through any
openings that may exist, and a hollow trunk is the
result.

Tlie almost constant presence of moisture, and vary-
ing temperature, are the main factors that admit O'f
fungi effecting the rapid disintegration of dead vege-
table matter in woods, etc. As is well known, wood
that has been properly seasoned remains sound for
centuries, but if allowed to^ become damp, then fungus
scavengers, under the guise of " dry rot "' {MeruUus
lacrvmans), or other forms, at once commence the work
of disintegration.

.A.S an article of food, the nutritive properties of fungi
have been much over-rated in the past. It was [x>inted
out that owing to their nitrogenous nature they stood on
a par with animal food, whereas in reality modern
analysis proves tliat the comf)osition of fungi varies
very much in different kinds; and fromi a nutritive stand-
point the common mushroom (Agaricus campesiris), the
kind most generally eaten in this country, ranks with
cabbage rather than with beef.

This fact, howe\er, by no means proves that fungi
are comparatively useless as food; in fact, the oyster,
from the purely nutritive standpoint, ranks little above

fungi and cabbage, nevertheless it is considered a
luxurj^; and in the same sense, fungi may be regarded
rather as luxuries than otherwise, and are of use in
rendering more pleasant to the palate substantial
articles of food.

Tliere are in Britain at least fifty different kinds of
fungi that have been thoroughly tested as to their edible

2. Veasts: a, beer yeast \>iacrh^ro>iiyc(i rerevisiiF) , x, single plants; w
showing reproduction by buddinfr ; 7), wine yeast iS/tfcharomin;:.^
€tilip.muU:uii), X .single plants; tt showing reproduction by budding.
Mag. 800 times.

3. Ergot iChiTicepd luri.uu'ii]; a, growing on an ear of rye; ''. ergot
removed from its host-plant; c, ergot producing its second form
of fruit after lying on the ground throughout the winter. Nat. size.

properties, and from amongst these the great variety
presented, so far as taste and aroma are concerned, is
undoubtedly sufficient to meet the requirements of the
most fastidious.

Aroma is most pronounced in the subterranean fungi,
which include several edible kinds of truffle. The use of
the strong smell to these fungi is to indicate their pre-
sence to various animals to whom they serve as an
article of food ; by this means the spores are dispersed.

From among tfie number of species eaten in England
by mycologists, the one we consider best of all is a fun-
gus which, although by no means uncommon, and during
certain seasons very abundant on the ground in woods,
is probably quite unknown to the majority of people.
It is known as the " horn of plenty " {CraicrcUus
cornucopioidcs), on account of its resemblance to the
allegorical Cornucopia, as represented in pictures. The
general form is that of a long, narrow funnel with a
wavy mouth, two to four inches high, inside blackish-
brown, outside grey. This fungus cannot possibly be

Jri.v. 1004.]

KNOWLEDGE & SCIENTIFIC NEWS.

143

mistaken for any otiier less desirable, kind, and w Iumi tlio
first prejudice has been ovcrcomo, it will doubtless l^e
added to the list of t;ible delicacies.

A peculiar funyus of a somewhat gelatinous consis-
tency and brownish-red colour, having; a resemblance in
shape a human e:ix, and popularly known as " Jews'
liars " (Hinicola aurlciihi-liidiia'), is not uncommon on
dead elder trees, and although not usually included
under edible species in this country, is perfectly safe to
eat, and a closely-allied species {H. polytriclia) is
esteemed as a luxury by the Chinese, by whom it is
cultivated on a large scale. When dried, the price of
this fungus rang-cs from .£30 to £50 per ton, the retail
price being about one shilling per pound. This fungus
occurs in abundance in \cw Zealand, where it is
collected for the Chine.se market, the annu.nl value of
the exports ranging between £15,000 and X-(o,ooo.

These amounts are, howexer, entirely eclipsed bv tlu'
hundreds of millions of pounds sterling expended

4. Fungi t^rowiog on insect.s; a, '-, Curdijcrpg mi/itartt ; '/, conidial; li
axiferous form of fruit; buth are growing on th.; chrysalis of
some inject; c,Cordtjeep% a>i:ularix, growing on a caterpillar. Nat.
size.

annually on products depending entirely on the work
done by a lew closely allied and lowly organised species
of fungi known as \'easts {Sacc/iaromyccs). I'he pro-
ducts alluded to are fermented or alcoholic liquors ;
wines, Ix-crs, and b.ome-made ginger-beer alike owe the
amount of alcohol they contain to the activity of yeasts.
The yeasts are very partial to sugar as food ; in the
production of wine, the sug-ar is present in the juice from

the crushed grapes ; in Ijreu ing lie<'r tin- starch pr<'s<'nt
iiii barley is converted into sugar during the preliminary
process of malting. In either case yeast is added to the
sugary extract, and wheni tlu- prop-cr leni|)eralnrc is
maintained, fermentation takes plarc. Such fermenta-
tion is the index of the \ital arti\il\- uf the \t'asl or
lungus present in. the solution.

1,'nder such favourable condilions as regards tempera-
ture and food supply the yeast grows very r.apidlv, in-
creasing in numbers by a rapid vi'gvtative or non-sexual
method called budding-. During this acli\ity the sug:u-
is u.sed ;vs food, and the by-producls, or lli(',<-;e portions of
the sugar not utilised by the fungu.s, .-iri' gixcn off under
the form of carbonic-acid g:i,s and alcohol res[wi-li\cl\'.
The former is the cause of the bubbling or efferxescence
as it escapes intoi the air, the l;ilter remains in Ihe
lir|uid.

In olden limes, the sweet wort or g?'ape juice was left
expO'Scd tOi the air, .and fermentation was effected by
yeast cells present in the air coining inito' (~onta,ct with
the liquid. .\t llie pi-esenl time llie \c,isl Is ridded to
the liquid, and in some breweries pure cultures of differ-
ent forms O'f yeast are used, depending on the (|u.ilily,
flavour, or keeping- power of the beer desired.

V'east is quite as indispensable to llie I)al<er as to tin;
brewer. To the latter it has beeni shown that alcohol is
the by-product ol most value ; whereas to the baker, who
utilizes the yeast for the purpose of leax'eiiing bis dough,
the carbonic-acid gas is most im|)orlant. The fungus,
being thoroughly mixed with the <loug'hi containing-
sug-ar and water, coim-mences active growth, ;md flic
carboinic-acid gas liberated bubbles up tlirougli tlie
tenacious dough and converts it into' a liL;lit, s])oiigv
mass, 'lire alcohol formed is dis.sipated (luring the
process of baking-.

\\'ith one important exception liirgi are not used
medicin:illv, unless the lanious t'liinoe rungiis is ad-
mitted. The oine included in tlie Hritish- l'li;irniacnp<ela
is Ergot (Claviceps pur piirea)^ the sclerolium of a fungus
parasitic on the ears of rye and numerous olher grasses,
.-mtl h;is ;i wide distribution.

When flowers of rye, wheat, or p;isliire grasses are
infected by the spores of ergot floating in tlic air, the
part developing; into a grain under noi-ni:il i-on,ditions
bec-o^n-ies changed into^ a black, horn-sli.-iped hoflv .-ibout
half an incli in length, and coirposerl of a srlid iiia^s ■
O'f mvc<.-liiim, termed a, sclerotium ; this is llu" l'^r!7(;L "i
part used medicinally. It cont.'iins a siib.sf.-inij^j^alird
lirgotine, which, although iJoisonous, is (>£^'real'',v;ilut;;<
as a medicine. ' -^ r\'>\'^

When the h'rgot is mature its surface is eo\erG^^with
myriads of very minute conidia, or summer-sporeSjjC
wliich are immersed in a somewhat yisod,'. sweet SM^V
stance that is \c.ry attractiye tO' fhe.^'Vn'irl Otheri' small
insects, who, in \isiting one grass floaver after another,
disperse the conidia, and thus elfect the distribution of
the fungus. When the grass <lies iiii the .•iiitumn the
Ergots fall to the gronnd, .and remain unrliangerl until
I'le following- spring;, when a new form of Iniil grows
frofin the sclerotium, the spores of wlii<'li infect the
gr;iss flo'Wers in the spring-.

Xo'twithstanding- its medicinal value, b'rgol is said to.
cause serious diseases to human beings when, it is
ground up along- with grain toi form flour, and when
e;iten by horses or cattle it causes abortion.

The Chinese fungus alluded to, and called " summer
p'rmt, winter worm " bv the Celestials {Cordyicp^
sinensis), is interesting as being one of a small g-roup of
funL'i that develop on living- insects. .Some attack
moths, wasps, Ac, but the majority are met with on

144

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

caterpillars. Although the caterpillar is alive when
infection takes place, it slowlj- dies, and its body be-
comes filled with a dense mass of myccliiini, from which
one or more simple or branched, cl<)n4,'-aled Iruiting-
bodies spring at a later period.

One very beautiful fungus belonging to this section is
not at all uncommon in this country-, it is called Cordy-
(cps militaris, and is generally found growing up
amongst moss in damp places in woods. It is club-
sh.iped, one to three inches high, and of an orange-red
colour. If the stem is carefully followed down, it will
be found to spring from the pupa of some moth or
butterfly.

At the present time the knowledge that certain fungi
attack and destroy insects has been turned to practical
account. Fungi attacking insects injurious to crops, as
locusts, cockchafers, <.tc., are cultivated on a large scale
for the purpose of .securing quantities of spores. These
spores are preserved in small sealed glass tubes until
required. When an army of locusts appears the con-
tents of one or more tubes are mixed with water and
placed on bread or some other substance eaten by the
locusts. The spores thus eaten germinate quickly in
the bodies of the insects, and death soon follows. Now
a^ it is the custom among locusts tO' eat their dead
friends, the infection spreads at a great rate. By such
means large areas have been cleared of destructive
locust swarms in -South .Africa and elsewhere.

Before the discovery of lucifer matches, a large hoof-
shaped fungus {Polyporus fomentarius), growing on the
trunks of trees, was used throughout Northern Europe
for making amadou or tinder. The thick, brown woody
flesh of the same fungus, cut intO' slices and beaten until
it assumes the appearance of felt, is used at the present
day in Germany for the manufacture of chest protec-
tors, caps, purses, bedroom slippers, and various other
articles. .V good assortment of such, along with ex-
amples of the fungus and the felt, are exltibited in the
Cryptogamic room, No. 2 Museum, Kew Gardens,
where many other interesting forms of fungi are also
on view.

The fact that Lichens differ from other plants in being
partly fungal and partly algal, the two collectively con-
stituting the plant, is well known. This condition of
things is called symbiosis, vmtualism, or commensalism ;
\\ hich means tliat each benefits respectively by the par-
ticular kind of work done by its neighbour, the total
result of such mutualism being that Lichens can grow
luxuriantly in IfKalities where neither fungi nor alga?,
as independent plants, could flourish. It is important to
understand clearly the difference between a parasitic and
a symbiotic fungus. TTie former is always injurious,
without txjnefiting in any way the plant it is parasitic
upon. The symbiotic fungus benefits, without in anv
u ay injuring, the plant it is associated with.

.Symbiosis between fungi and other plants has of late
years been shown to be much more general than \\as
suspected. In many forest trees, as spruce, larch,
silver fir, oak, beech, hazel, A-c, the fine rootlets that
supply the plants with food are entirely surrounded by a
dense weft of fungus mycelium, which acts on the
humus in which the plant is growing, in other words,
converts the humus into food tli.-it can be absorbed bv
the r(x>t of the tree from the fungus surrounding it.
The fungus and the rootlet it surrounds is called a
mycorhiza.

Heaths, orchids, ferns, and all flowering plants not
possessing chlorophyll possess mycorhiza, on which the
l.-.st named are entirely dependent for their food supply.

FoLStirvg AnimoLls.

Bv R. Lydekker.

The fact that a large number of species of mammals
and other animals undergo more or less prolonged and
continuous fasts during the period of their winter or
summer sleep is familiar to us all. .A.nd although un-
doubtedly remarkable, the phenomenon is not such as
to excite any great wonder or surprise in our minds ;
for during the periods of such slumbers the more active
functions of the body are to a great extent suspended,
while those that are carried on act slowly and entail
comparatively little waste of tissue and energy. More-
o\ er, before the period of the winter torpor or hiberna-
tion takes place, many of these animals, such as bears,
accumulate large stores of fat on various parts of the
bixly, which suffices to supply all the waste entailed by
the respirators' function during the period in question.
Fat is also accumulated by certain species, such as the
mouse-lemurs of Madagascar, previous tO' the summer
sleep, or aestivation, and is used up in a similar manner ;
such summer sleeps being, it should be noted, under-
taken for the purpose of avoiding the season of great
heat and drought, when food is difficult or impossible to
prixrure. Other species, on the contrarv, like squirrels,
dormice, and hamsters, lay up supplies of food in their
winter c|uarters, on which they feed during waking
inter\-als in the torpor, sO' that the fast is by nO' means
so prolonged or so continuous as in the case of the first
group. There are, however, yet other animals, such
as bats, among mammals, frogs and toads among
amphibians, and the We.st African lung-fish among
fishes, which apparently neither put on fat nor lay up a
store of food during their period of torpor ; which in
the case of all of them is unusually prolonged. Bats, for
instance, generally remain torpid throughout the winter
months ; while the .A.frican lung-fish passes the whole of
the dry season comfortably curled up within a nest
formed bv the caked and dried mud of the river bed.
In all these latter cases the fast must accordingly be
prolonged and of a severe type.

Nevertheless, whether partial or continuous — whether
mitigated by a store of fat or food or not — all such fasts,
as already said, take place when the chief functions of
the bodv are more or less completelv in abeyance.

In marked contrast to the above is the case of cer-
tain members of two widely sundered groups of
animals, which undergo a protracted voluntary fast
during the breeding season, when the bodily functions
are in their highest activity, and there is a strain on the
whole system which is unknown at other times. How
the creatures manage tO' exist at all under such circum-
stances is little short of a mar\-el ; nevertheless, not
only doi they exist, but for the greater portion of the
time they are in the very pink of condition, and it is
only when the breeding season is over that they fall
away and require a period of rest and good feeding in
which to recruit their energies.

The creatures in question are the sea-lions and sea-
bears on the one hand, and the salmon on the other.

The fact that the adult males of sea-lions and sea-
bears, which constitute the family of eared seals, or
Otariidce, fast while on shore w-ith their " harems "
during the breeding season has been known for a long
time ; but it is onlv recentlv naturalists have satisfied
themselves that the salmon abstains from food, almost,

Jui-Y, 1904.]

KXOWT.F.nGE & SCIENTIFIC NEWvS.

145

if not quite, entirely durinjj the period of its sojourn in
fiesh water.

As roijards the fastint; of the eareti seals, we may
take the case of the fur-seals on the I'ribiloff Islands, in
Berinj;^ Sea, as described by Messrs. Jordan and Clark
in the Report of the L'nited States Kur-Seal ln\eslii;a-
tion, publisiicd in 1898.

As regards the females, or cows, it is stated that after
their first landings they do not leave the islands for ten
or twelve days, during: which peri(xl they must, of
course, abstain from fo<xl. \\ hether such periods of
fasting are regular or not is, however, at present un-
known ; but it is certain tluit neither the cows nor the
young bulls (bachelors) fast for any considerable part
of the summer, if for no other reason, from the circum-
stance that they maintain a uniform condition througlir
out the season, always showing- a plentiful stock of
blubl>er, and never looking worse at one time than at
another.

\'ery different is the case w ith the old bulls, which
come ashore about May i, and do' not again go to sea
till al)out July 25, during the whole of which time they
remain entirely without f(Kxi. Like many hibernating
mammals in autumn, they are quite laden in spring- with
fat or blubber, which is gradually absorbed while on
shore, leaving the :mim;ds thin and greatly reduced at
the close of the breeding season. With regard to the
condition of the old bulls as the)' leave the islands after
iheir long- fast, some degree of misconception appears
to obtain, for although they are undoubtedly much re-
duced in condition as compared with their state in the
spring-, yet they are by no means so poor, either in body
or spirit, as has been reported. So long- as they remain
on the breeding-grounds they retain sufficiejit fighting
power and courage to make themselves masters of the
situation, and it is only when they move down to the
sandy beaches, preparatory to« taking to the water, that
they become tame and tractable.

Turning now to the case of the salmon, it may be
mentioned that, so long ago as the year 1880, Professor
Ruesch published a refx>rt upon observ-ations made on
Rhine salmon, w-hich tended to show that while in fresh
water these fish, contrary to popular opinion, seldom or
never feed. In fact, among- two thousand salmon exa-
mined, in only two — and these kclts, or out-of-condition
fish- — -w-as any trace of food found in their stomachs,
which in most cases were wrinkled up and contracted,
showing that they had not contained food for a long
time. These observations have been fully confirmed by
the exf)eriments and examinations recently undertaken
on behalf of the Fi.shery Board for .Scotland ; while
these, ag-ain, have been checked, and in some measure
corrected, by the independent investigations of Dr. K.
Barton. The net result of all these observations is to
render it practically certain that from the time they
leave the sea until the completion of the spawning opera-
tion .salmon, as a njle, take no food of any kind. As re-
gards kelts, or spent fish, much the same appears to be
true in their ca.se also, but from time to time traces of
f(Kxl have been detected in the stomachs of such fish,
showing that they occasionally seize and swallow a
tempting morsel. In some slight degree the latter
circumstance tends to confirm the popular idea that
kelts are more greedy than salmon : the term " hungry
looking kelt " being common among fishermen. Never-
theless, the popular idea is in the main wrong, since
most kelts ("unless, perhaps, in cases where they are pre-
vented from getting back to the sea owing- to the low-
ness of the water) fast as completely as salmon while in

fresh water. It may thercloie be taken as an estab-
lished fact that the true feeding-ground of the salmon
is the ocean, and that while in fresh water these fish pre-
serve a more or less strict and coiiiplcle fast.

.Much the same is true of the Pacific species of sahnon,
which belong to a distinct genus (Oticorliyncliiis), and
afford a large proportion of our supply of tinned salmon.
After leaving tidal waters the throat of the-se fishes be-
romas contracted, and their stomachs are almost always
found to be empty.

'' The tendency to feed," write Messrs. Townsend and
.Smith, " becomes less the longer they remain, and when
one has seen the enormous runs of salmon that some-
times actually crowd the streams, so that it would be
impossible to wade without stcjiping upon them, it be-
comes apparent th.-it they could not make their rapiil
journeys to the head-waters of the largest rivers and
have time to feed, and that there could not be food
enough to supply them if they required it. If such
hordes should become hungry while on the spawning-
grounds hundreds of miles from the sea, one could
imag-ine the effect on the sp.-iwning operations.

'' .As a matter of fact, the salmon, after leaving tide-
water, li\es on its own supply of fat and blood. Its flcsli
I'ccomes less an<l less re<i, and the fish becomes thinner
as it advances up stream

" The degree of emaciation reached and the extent of
the injuries received by the salmon by the time it has
spawned preclude the possibility of its recovering, even
if it reaches salt water alive. Death is a natiir.il result
of the conditions."

In thus starving and spawning themselves to death
Pacific salmon (of which there are several kinds) differ
markedly from our own Salmo salar — by far the finer
and nobler fish — ^which may return to its sp;iwning-
grounds for several years in succession.

.As regards the origin of the fasting habit in salmon,
it might at first sight be supposed that all the nemhers
of this group were originally sea fish which acquired the
habit of entering rivers to spawn, and that, finding the
food to be obtained in fresh waters unsuitable to their
taste, they refrained from feeding-. Apart, however,
from the question whether the group may not have been
originally a fresh-water one, there is the fact that young
salmon — parr and smolt — feed greedily in ri\ers, where
the former are hatched.

The authors here cited suggest that, " in the process
of evolution, the salmon may have lost the desire to feed
in fresh water through the competition met with in the
ascent of the rivers, the great distance to be traversed,
and the lack of food in any stream necessary to* supply
as greatlv increased a pf)pnlation of fishes as occurs in
the spawning season."

Whether or no this be the true explanation in the case
of the members of the salmon group, the voluntary fast
undertaken during the breeding season bv those fishes,
and bv the old males of the sea-lic/ns and sea-bears, is
one of the most wonderful physiological phenomena to
he met with in the whole realm of organised nature.

.^ Continental invention for automobile signals makes
whistles of the hollow spok&s of the wheels. These are
operated by the air a/Ction, oif the wheels in. turning, and
controlled by a series of small rubber balls. The balls
are contrf>lled froim the seat, their release opening the
valves in the spokes and producing a peculiar whistling
noise ea.silv heard above the noise of traffic.

146

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

Photography.

Pvire dLrvd Applied.

By Chapman Jones, F.I.C, F.C.S., &c.

At the recent con\-ersazione oi tlie Ro}al Society there
were many exhibits that owed tlieir orig-in, at least
partly, to photography, such as an optical bench for
testing- lenses, by Messrs. R. and J. Beck, three-colour
photographs projected by a lantern in which spectrum
colours were used instead of coloured screens, by Sir
W. de W. Abney, and photographs and photo-micro-
graphs of vario'us kinds. But the exhibits tliat seemed
to me the most striking- were the stereoscopic trans-
parencies, by Mr. Francis Fox, of the Simplon tunnel,
now in course of co^nstruction through the Alps, and of
the \'ictoria Falls, and also some three-colour lantern
slides by Mr. E. Sangei'-Shepherd. The first showed
how perfectly stereoscopic transparencies, well mounted,
convey an impression of the actual object. And when
such views are supplemented as these were by samples
of the rock taken from the tunnel, one obtains as good
an idea of the actual circumstances as is possible with-
out visiting^ the place itself. Indeed, it is doubtful
whether a visit would give much more information to
the ordinary observer. The three-colour lantern slides
were of various spectra, and produced with such a
degree ol fidelity that they might well be used for
lecture demonstrations when it is desired toi show
spectra rather than the means of producing them. It,
for example, it were wished to sho'W the spectra of the
rarer gaseous elements recently isolated, the use of
such slides would give quite as good, if not better, re-
sults than the production of the actual spectra, without
the cost and risk of employing tubes of the gases them-
selves, and the trouble of fitting up spectroscopic ap-
paratus. Moreover, the slides would probably give a
more representative effect, because thev would be made
under the most suitable conditions, instead of having
to get the result during- the exigencies of the lecture,
and the projection on a screen would be much
preferable to the necessity that often arises in such
ca.ses of pro'\-iding instruments for the direct eye ob-
servation of the few members of the audience that are
f(jrtun;ite enough to- gain access toi them.

Rc'-crsa/. — The reversal of the image is one of the
must inleresting and n-ivslcrious of photogfraphic
phenomena. Professor K. \\'. \\'ood has catalogued
five kinds or types of reversal, ;ind it has been suggested
th.'it at least one more should be added to- these. 1
think, l-iowe\er, that these should be called methods
ratlier than kinds of reversal, and believe that there is
g-ood reason for considering that there are probably
only two kinds of reversal, which I suggest might well
be called progressive and retrogressive respectively.
That is one in which the effect of the light action is con-
tinued, and one in which it is undone. If the effect is
resrarded as a rotary one, then that part which rotates
would continue, in the first case, to rotate in the same
direction, while in the second case it woiild turn in the
backward direction, both arriving at, or tending to-
wards, a zerO' or p.seudo-zero point. It does not follow-
that retrogressive reversal would of necessitv leave the
sensitive substance in just the sanie state a.s it was be-
fore it h:id been affected by light. I shall probably
return to this subject on another occasion.

Reversal in Shutter-Speed Tests. — My present intention
was not to theorise on reversal, but to refer to a practi-
cal result of the Clayden effect; that is, reversal of the
developable condition that has been produced by a short
exposure to. an intense light, by means of a subsequent
comparatively long- exposure to a feeble light, the latter
not producing reversal when it precedes the former. In
the use of Wynne's shutter-speed tester, a convex
polished metal button moves in front of a graduated
diagram, and it is photographed while the sun shines
upon the whole arrangement. The length of the streak
of light produced by the moving button indicates the
period of the exposure. By moving- upwards or down-
wards the pendulum that carries the bright button,
several tests may be made on the same plate, if the
camera is not moved. Under these circumstances the
comparatively feeble light from the diag-ram produces
its effect over the whole surface of the plate during
each exposure, including those parts where the bright
light from the button imping-es on the plate, and this
gives the superposed intense and feeble exposures which
are liable to give reversal. I made seven tests on each
of a few plates, and generally the first streak was re-
versed, the second and third were hardly discernible,
the exposure effect from the bright button being incom-
pletelv reversed and the result neither one thing nor
the other. 1 find that it is best tOi start with, the longest
exposure and to let the others (generally not more than
three) follow. When giving 8, 6, 1^7, and J hundredths
of a second in the order stated there was no' reversal.
But 20, 3, 2, I, and ? hundredths of a second gave
reversal for ij divisions and a feeble effort for the next
4 divisions (each division equivalent tO' tlie hundredth
of a second) of the beginning' of the first streak. Tlie
rest of the streak representing the first exposure, and
all the others were represented by good black lines on
the plate. With a series of 27, 11,7, and 2 hundredths,
4.5 divisions at the beginning of the first were reversed,
the next 10 were feeble, and the remainder good strong
images. Tlius the Clavden efiect interferes som.etimes
in ;i verv practical wav under vei-y coimmon-place
circumstances, and it is desirable tO' bear this in mind
when giving- multiple exposures, as is often done in
experimental work. In the particular case referred to,
if the sunlight were constant in its brilliancv, the streaks
on the plate would all have practically the same ex-
posure, the long-er exposures simply giving- longer
streaks. But the leng-th of the exposure would affect
the general illumination of the plate by the surface of
the diagram, and it seems that it is desirable tO' have as
little as possible of this tO' jnUovj or to> be superposed
u|-)on the exposure effect due to the brilliant light re-
flected from the polished button.

S pirit Levels. — \o camera intended for general work
is complete without some means of showing; when the
sensitive surface is perpendicular, and in by far the
greater number of cases a circular spirit level is the most
convenient and effective apparatus for this purpose.

Messrs. Taylor, Tavlor, and Hobson many years ag-o
introduced the level shown in section, and were there-
by successful in obviating the leakage which, before

July, 1904.]

KXCnVLT-DGK c'v SCIENTIFIC NEWS.

147

tlien, was rarely avoided. The glass, H, is united to
the cell. A. liy the ela.stic ring", D, the whole beinii- held
tosjcther and protected by the outer casing- K. They
have now introduced a level made on exactly tlie same
lines but with the tlan§:e for attachment to the camera
at the upper part instead of the lower part of the body,
so that the level, when fixed, presents a surface almost
flush with the woodwork, as shown in the second

figure. These will be useful in cases where the others
were impossible. There is one matter concerning- the
fixing^ of levels th;it is not always attended to, namely,
that their sole use is to show when the plate is vertical.
They must, therefore, be fixed to that part of the
camera that carries the plate. If the back of the
camera swings, the level must be attached to the back;
it would be useless on the base-board, except only when
the swing-back was not in use, and it was certain that
the plate was perpendicular to the base-board.

Notes on the R.et\jrn. of
Ei\cke's Comet.

This comet will be favourably visible this year during-
the autumnal montlis. I'erihelion will be reached on
1905, January 4, but it will probably be picked up in
some of the large telescopes employed in cometary work
in .August and September next. Its nearest ap-
proach to the earth will occur in, the third w-eek of
November, when its distance will be about 35 millions
of miles.

On October 4 the position of the comet will be about
midway between the stars /? -Andromedae and o Trian-
guli. Moving- westwards it will be found 5° N.E. of /i
I'egasi on November i. Its appiirent motion will in-
crease, and in November and December be directed to
S.W. Early in December the comet will be close to
the brilliant star a -Aquilse (.Altair). At about this period
it will be easily visible in smaJl telescopes, and may
possibly be within reach of the naked eye.

This will form the 36th return of the comet (and the
29th observed apparition) since it w;is first discovered
by Mechain in 1786. .At intervals of 33 years (including-
10 p>eriods) the jserihelion is reached at nearly the same
time of the year as before, and in 1904 the favourable
prasentations of 1805, 1838, and 1871 will be repeated.
In the three years last mentioned the comet was visible
to the naked eye. Drawings of its physical aspect in
1871 appeared in Monthly A'o/ices, XXXII, pp. 26 and
217, and Astronomical Register, X., p. 13.

The comet has been seen at every return since 1819.
The following- is a list of its perihelion passages, ob-

servers, and perio^ls. The average duratioii of a r<'\(ilu-
tion from 36 returns appears lO' be 1,206}, days. The
nature of the orbit was deterniincd from the observa-
tions in 1819.

R^eturrvs of Encke's Comet.

I'lr.l.L

Hull.

Ollsc TM-r.

\h-.c

UVLlUl.

Pcrioil
n.iys.

• I7S6

I. .

Jan.

Mechain

1786

Jan.

1795

. Dec.

C. Herschel

1795

Nov.

1204 (3)

t IS05

. Nov.

Thulis .. ..

1S05

Oct.

1208 (3)

iSig

1. .

. Jan.

Pons

1818

Nov.

1204 (4)

1S22

II. .

. May

-3

Kumlier . . . .

1.S22

June

12 I 2

1825

III. .

. Sept

Valz .. ..

1825

July

■3

I 212

; i«29

. Jan.

Struve . .

182S

Sept.

1 5

I2II

I<Sj2

i. .

. May

Mossotti . .

I, S3 2

June

I 2 1 0

•' 1835

II. .

■ Aug.

Kreil

■835

July

I2I0

IS38

. Dec.

Boguslawski ..

i8j8

Aug.

I2II

1842

i.' .'

. .\pril

(ialle .. ..

1842

Feb.

I2I0

■S45

IV. .

• Aug.

Walker .. ..

iS-t5

July

I2I4

1 8.(8

11. .

Nov.

G, P, Bond ..

1848

Aug.

1205

1852

I. .

. Mar.

Hind .. ..

1852

Jan

1204

1S55

IV. .

luly

Maclear . .

1855

July

1204

1S58 VIII.

Oct.

I.S

Fiirster . .

TS58

Aug.

1205

1862

I. .

. Feb

Furster . .

18O1

Sept.

1207

1865

II. .

May

D'.\rrcst.. ..

i8f..5

|an.

1206

186S III. .

. Sept

Winnecke

iS(>8

July

1206

1S71

V. .

Dec.

Winnecke

1871

Sept.

I2CO

1S75

I. .

April

Holden .. ..

187.5

Jan.

1202

1S78

II. .

Julv

2(,

Tebbutt .. ..

1S78

Aug.

1200

S 1881

VII.

Nov.

Hartwig . .

1 88 1

Aug.

I20S

1885

I. .

Mar.

Tempel . .

1884

Dec.

1208

I88S II. .

June

Tebbutt . . . .

1 888

July

i2og

I8gi

III. .

Oct.

Barnard . .

1 89 1

Aug.

1207

1895

I. .

Feb.

Perrotin, Wolf

1894

Oct.

1206

1S3S

III. .

May

Grigg .. ..

iSgS

June

1207

190 1

I. .

Sept.

Wilson . .

1901

Aug.

1207

U 1905

I. .

Jan.

) -

—

1207

* Discovered near the star ^Aquarii. Observed on two nights (Jan, t7 and 19)

only.
i Independently discovered by Pons, Bouvard. and Huth, on Oct. 20, 1805. It

had a tail 3 ' lon^j,
; Distinctly visible to naked eye at end of November.
•"Boguslawski picked np the comet on July 30.
S visible to the naited eye at Bristol in October.
Computed date of perihelion passage.

There were se\en unobser\ed return,'
between 1786 and 1819, coinpuled by
occurred as under : —

1789

1792

1799

1802

1809

1812

tO' perihelion
■".n<-ke to have

May 19.

September 4.

.April II.

.August 2.

March 12.

June 26.

October 13.
Encke found the period of the comet in 1789 to have
been 1,212 days 19 hours. .Seagrave, in L'opiihir
Astronomy, 1904, February, gives the present period as
1,206 days 20^ hours, and says the time has decreased
\erv nearly six days. This decrease would amount to
about four hours per revolution. He gives an ephemeris
for the coming return, but it has not been corrected for
perturbations, and will, therefore, not accurately repre-
sent the path of the comet. No doubt Mr. Crommellii
V ill supply a reliable ephemeris in later months. The
comet, having: a very interesting history as the first one
known belonging- to the Jovian family, as having-
suggested the idea of a resisting medium, and as having
a smaller orbit than that of any other comet, should be
followed by everyo^ne possessing a telescope next
autumn as it travels from .Andrometia slowly through
Pegasus and .\quila southwards to Capricornus.

W. E. DENNINti.

148

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

Jvipiter,

It is fortunate that in recent years Jupiter has been
studied attentively at every opposition. The markings have
been watched from the time when the planet rose about
two hours before the sun to the time when he set about two
hours after it. In fact, the observations have generally
ranged over nine months of the year, and have been only

*x (*/Cy //("

C^^it/ii.r: 1: A-i

discontinued when Jupiter approached near the sun-
Since iSi)8 we have gained a useful insight into the rates
of motion of the various currents, and of the positions
and changes of the belts. This continuous study of the
Jovian surface must be maintained. It will ultimately
prove of great value in elucidating the changes taking
place in the velocity and aspect of the various spots, and
it may be the means of revealing periodicity either as
regards the motion or appearance of certain features.

In and since the year 1898, the writer, at Bristol, has
found the rotation periods of the chief currents as
under : —

Year.

N.Temp

N. Trop.
h m. s.

Eqja.

Red Spot

S. Temp.

h m. s.

h in s

h. m. s.

189S

0 55 50- 1

9 55 26- 3

9 50 236

9 55 4I-S

9 55 20 5

iSgg

.. .. 53-5

,. ,, 2S.S

., ,,246

,. ,.4l-9

.. ,. 18.6

1900

• i .. 30.0

,, ,. 24.1

,, .. 41-7

1 90 1

,. .. 5^ -^

,. ..316

.. .. 29.1

,. „ 40 9

,. .. 19-

1902

,. .. 5''j-5

.. ., 2g.S

,. ., 26.7 ., ,, 39.0

,, ,. 18.7

1 90 J

,. .. 54 3 .. .. 319

,, ,. 279 ., „ 41.6

,. .. 1S.5

Somewhat similar observations and reductions have
been made in recent years by Professor G. \V. Hough,
Captain Molesworth, Rev. T. E. R. Phillips, and ^Ir.
A. S. Williams. When the work has further progressed
through future years it will be important to compare all
the accumulated materials to see whether some useful
deductions cannot be made from them.

The mean periods of rotation from all observations in
the table are : — N. temp, spots = 9 h. 55 m. 53 s,,
N. trop. spots = 9 h. 55 m. 30 s., Equatorial spots =
9 h. 50 m. 26 s., Red spot = 9 h. 55 m. 41 s., S. temp, spots
= 9 h. 55 m. 19 s. Thus the N. temp, spots move slower
while the equatorial spots move quicker than any others
observed in recent years. Of course, the most interest-

ing object on the planet is the great red spot which for a

long period has been so faint as to have scarcely merited
that dtsignation. But it was a little p'ainer during 1903
than in the few preceding years, and possibly it will be
still darker during the present summer. The following
are a few times when this marking will be onor very near
the planet's central meridian. If the spot should not be
visible the conspicuous hollow in the S. equatorial belt
will show its position, and the time of transit of the latter
object should be taken.

Date Transit of Red Spat.
1904. h. m.

June 2 15 25

7 '4 34

9 . . . . . . . . 16 12

14 15 21

19 14 29

21 16 8

24
26

13 38
IS 16

To the \arious other markings particular reference
need not be made. In recent years they have, however,
been very numerous, and many of them conspicuous.
Any spots which may appear near the poles of the planet
should be watched with great attention.

■ W. F. Denning.

The Leg ©Liid Foot of a.
Spider.

At the con\ersa/iiMie of the Royal Society this photo-
micrograph, which forms our full-page illustration, was
h;liQwn, with many others. The aim of the exhibitors,
Messrs. Arthur M. Smith and Richard Kerr, w.is to
point out the value of direct photography on to a \i by
10 inch plate and to show its advantages over enlarge-
ments made from smaller neg-atives. The details ob-
tained at once by combining an unusually large camera
u ith a monocular microscope are greater than those
secured by ordinary amplifying methods. Tliis illustra-
tion represents aiv enlargement of 260 diameters and
has been obtained by a one-inch objective and a l(x;al
length of 37 inches approximately. The negative has
received no touching up whatever.

The expyedit'ons at present jiJIoat and organising for
discoveries in the North Pole regions, as summarised
by the American Inventor, are (1) that of the Russian
r.aron E. Toll, wlio left the island of Kotelnoi, in the
New Siberian group, over a year ago, and has not since
Ijeen heard from ; [2) the new Ziegler expedition, com-
manded by Captain John Haven, which left New York
last spring, reached Tromsoe near the end of July, and
upon attempting to make Frtmz-Josef Land met with
obstacles which have deferred further attempt till next
spring ; (3) an expedition projected by Captain Drake,
who will sail for Madivostok and Point Barrow in
.Vkiska, whence he will later make a "dash for the
Pole ■' ; and (4) Lieutenant Peary's new venture, which
was :mnounced in the early part of September. The
Norwegian Amundsen is supposed to be among the
island.s of British North .America, in search of the
magnetic pole.

The Leg and Foot of a Spider.

I50

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

The Solar Atmosphere
at Different Levels.

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

In " Knowledge" for October, 1903, we published a fine
[jhotO'g;raph o^f the sun in K-line, taken oni April 27,
1903, with the Ruml'ord .spectroheliograph attached to
tire great 40-inch refractor of the Yerkes Observatory,
Ijy Professor Georg-e K. Hale and Mr. Ferdinand Eller-
nian. Tliis spectroheliograpli, a photoigraph o-f which
was given in the same number, lias a train of twoi prisms
of 60", set at minimum deviation, for the K-line. I he
collimator and camera lenses arc of the portrait lens
type by N'oigtlander with apertures <y{ 6^ inches. They
are of equal aperture and focal length (33 inches), and
niay be focusscd singly or together by means oif a rod
connecting- the pinions which move each lens in
its tube. The tubes of collimator and camera are
parallel tO' each Oithcr, the light from the colli-
mator being- reflected Ironi a, plane mirror on to
llie fust surface of the prism train. If required, a
much higher dispersion can be obtained by substituting-
a grating-, ruled with twenty thousand lines tO' the inch,
fi r the above mirror, the first order spectrum being em-
ployed. The second slit of the instrument is, of course,
placed close tO' the focus of the camera lens, and the
gieat 40-inch telescope is made toi move slowly ini de-
clination, by means oi a slo'W motion electric motor, the
sun's ima.ge consequently mo-ving- at a. uniform rate
acro'ss the first slit, whilst the photographic plate is at
the same time driven at the same rate across the second
slit by m.eans of a shaft led down the tube of the tele-
scope from, tlie motor. The moition of tliie focal imag;e
of the sun, produced by the motor, is aboiit one minute
of arc in. foiur seconds, when, one set of gears is em-
ployed, and in twenty-four seconds when another. The
two' slits are each 8 inches in length, and are given
the proper curvature necessary tO' eliminate the distor-
tion of the solar image. But, as the focal leng1;h of the
great refractor is 64 feet, and the image of the sun, in
the principal focus is consequently a little over 7 inches
in diameter, the aperture of the spectrohcliograph is
not quite sufficient for a full in-iage oif the sun, and
occasioned the falling- oiff in brig-htness at the twoi oppo-
site limbs of the sun, noticed in the plate published in
■■ Knowledge," opposite p. 229 in. the last volume.

At that time Professor Hale wrote: — '' By setting the
.second slit on various parts o,f the K-band it is possi-
ble toi photograph sections of the calcium flocculi at
different elevations above the photo«phere. Tfijs is due
I'l the fact that the width of the K-band is determined
by the density of the vapour; hence, if the slit is set near
the outer edge of the laroa.d band, it cam receive light
only from the calcium vapour, which is den.se enough
to produce a band of this width. When the slit is set
near llie centre of the band it receives light from all the
vapour King belo,w the corresponding level. But as the
v;ipour expands as it rises, a given photograph always
shows the structure corresponding tO' the lowest density
(h.igliicst level) of the calcium \,-ipoiir competent toi pro-
duce a line of the necessary width. I shall publish very
soon a. series of photographs shmving how spots are
successively co'vered by o,verh.a.nging calcium clouds in
photographs taken at different levels."

'i'h.is promise has been fulfilled in the recently pub-
lished Memoir on the Rumford .Spcctrolieliograph whacb

forms \'ol. 111., Part 1., of the Publications of the
V'erkes Observatory, from which we are enabled to re-
produce four photographs out of the great number by
which the Memoir is illustrated. The four chosen,
Figs. I to 4, represent the great spot group of 1903,
October 9, as photographed with the slit placed in
three different positions on the H-line of calcium and
upon the centre of the F-line of hydrogen.

In the last number of " Knowledge," we reproduced a
portion of one of M. Janssen's superb photographs of
the solar surface, showing in a very distinct manner the
curious structure which, it presents. The minute
granulatio,n whichi the disk thus either shows tO' the eye
under the most perfect conditions of seeing, or reveals
to the photograpliic plate when the precautions taken

Fig. 5. H and k lines on (he L>isl\, in the Chromosphere, and in a
Prominence ui).

by M. Janssen are employed, has its parallel also In the
structure shown. Ijy the calcium " flocculi " (to adopt
the word suggested b\' Protessor Hale, and generally
accepted), re\ealed b\- the spectrciheliographi. l''rom
the greater difficulties of the work the granulation
shown by the flocculi is not in general so' minute as that
shown on |a.n.ssen's photographs, and in many cases
their granules appear to have run together to form the
great fleecv clouds sO' conspicuous in the photograph
reproduced in October of last year. Professor Hale, on
the working hypothesis which he at present employs,
considered the minute floccular granules as columns of
calcium v.apour, rising- abo've the columins of condensed
\ap0'urs of which photospheric granules are the
summits. The question arose whether these larger
calcium clouds wore made up of similar columns of

JflY. 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

151

MyMjji

^^ t ''-^p

i *i

Sr^

1
1

■^••»*^

f-'ig. I.— 1903— Ottober, i;d., 3I1., 42 m. Calcium Flocculi, Low H Level.

Fig. 2. — 1903 — October, od., 3 h., 43 m. Calcium Flocculi, Middle Hj Level.
THE UREAT SL'NSPOT OF 1903-OCTOBER.

It2

KNOWLEDGE & SCIENTIFIC NEWS.

rjuLv. 7904.

Fig. 3. 1903 -October, 91!., 3 h., 30 m. Calcium Flocculi, H Level.

il^

ttat:

^mmmm

IHHi

Fig. 4.-1903 October, 9d., 1 h., 4m. Hjdro;.;eii I'locculi
THE QREAT SUNSPOT OF 1903— OCTOBER.

July, 1904.]

KN(nVI.i:i)GE & SCIENTIFIC NEWS.

^13

calcium vapour, aiid the method by wliicli I'rolessor
Halo ende;i\ oured to answer this question is one ol
yroat ingenuity and interest.

Kelerring to I'ig- 5, which is extractetl Irom one ol
tl'.e plates ol the same .Memoir, the 11 imd K lines are
there seen as photographed on the disk in the chromo-
sphere and in a prominence. L'pon the disk the H antl
K lines iire seen as usual as broad and dill use bands.
These, in the chromosphere, are replaced by bright lines
whicli are fairly defined. \t tlie top of the figure, in a
prominence, these bright lines thin out into^ very much
narrower lines, changes wliich correspond to the differ-
ent phases of the bright lines of calcium, obtained when
a considerable quantity of calcium vapour is introtluced
into an electric arc. Under the.se circumst;mces, broad
bands, bright in the centre ;uid fading towards both*
edges, appear in the places of 11 and K. The width of
these bands decreases towards the outer part ol the arc
where the calcium vapour is least den.se ;uid relatively
cool; wliilst in the centre of the broadest purl ot the
bands a tliin dark line is seen, due to the absorption ol
this cooler rarer vapour in the outer part of the arc. So
it is no doubt with the calcium vapour surrounding the
sun. The darkness of the calcium bands, H and K,
would be due to the calcium vapour being cooler than
the photosphere below it, whilst their breadth would
indicate that in this lowest stratum it is of considerable
density. Higher up, as we see in the behaviour of the
bright H and K lines at tlie limb, the density of the
\apour is diminished, and the lines are fairly well de-
lined. For distinctness of reference. Professor Hale
denotes the broad diffu.sed bands as H, and K,, whilst
the narrower lines he calls H^ and K. ; the very thin
lines seen in the upper cliromosphere and prominences
being H, and K^. It will be noticed, on examina-
tion of the calcium, lines on the disk, that at times we
have a bright H.^ or Ko line, superposed on the broad
dark band H, or Kj whilst this bright line is bisected
again by the extremely narrow dark line Hj or K..

The explanation of the principle upon which Professor
Hale works will now be evident. If the second slit be
placed at the edge, say of the K, line, it is manifest
that only that calcium vapour which is sufficiently dense
to produce a line broad enough to reach the slit can act
on the photc^aphjc plate. The up[>er rarer strata of
calcium vapour, giving lines of smaller breadth, will lie
outside the slit, and their light will therefore be screened
from tlie plate. Under these circumstances the photo^
graph obtained is virtually that of the lowest stratum of
calcium vapour. If the slit be set nearer to the centre
ol the line, but not at the centre, it is clear that, as be-
fore, tlie highest strata giving lines too narrow to
enter the slit will be shut out from recording their pre-
sence. But it may be urged that it mig-ht nevertheless
include regions lying below it where the crdcium vapour
is dense enough to produce a broader line. However,
as Professor Hale puts it, " Since the calcium vapour is
rising from a region of high pressure to one of much
lower pressure, it must expand as it rises, and therefore
a section at any level should, in general, be of a larger
area tlian a section of the same flocculus at any lower
level. As a consequence of the increasing extent of
the vapour with the altitude, and the increase of bright-
ness observed when passing from K, to K^ a photo-
graph corresponding to a given level is not necessarily
affected in any considerable degree by the existence of
the denser vapour below, except in cases where the
high-level vapour does not lie immediately above the
low-level vapour." Broadly speaking, therefore, and
not using the term " level " in too precise a .sense of

altitude, it would seem lh;it this ingenious method does
give us a view of the distribution of the more or less
heated columns of calcium vapour at various levels
alx>vc the surface of the --un.

The first three photographs in the accompanying
plate.s show the well-known great spot of last October 9
as photographed with the slit at different positions on
the great H-line. l-'ig. 6 in the text gives the same spot
as photographed in the ordinary manner. In all three
of the calcium photographs some of the salient features
of the great spot group can be detected. The little
nearly circular herald spot, the heavy compact form (►(
the [irecedrng half of the great group, the sinuous bridge
which traverses it Irom west to east, and the more com-
()lex structure of the following half of the group, can
be made out at each of the three " levels." Hut whilst
the bright fiocculent matter is ijuite restricted in ari'a
and granular in chaiacter in the lirst photograph, it in-
crea.scs in brightness and becon-.es muclt more coherent
in character, extending over a much wider area as we
pr(K--ced from the first tO' the second photograph, and
again from the second to the third. Indeed, the bright
clouds of the third photograph all but hide the great
sunspot from view. The three pictures taken together

-adPad

3^^

Fig. 6. The Great Sun.spol of lyo,?. October t). Photographed with
the Ureenwich Photoheliograph.

seem to afford, therefore, clear indications ol the ex-
panding of the vapours as they rise.

The fourth plKvtograph (Kig. 4), representing the same
area ol the sun, differs from them totally in appearance.
This was taken on the h'-line of hydrogen. The little
pioneer spot can still be identified, and some portions nf
the umbra of the great spiH that followed it. lUil Ihe
spot as a whole is hardly rtx'ognisable, although its oul-
line is not concealed by spreading' masses of bright rluuds
a'v in the third calcium photograph. Indeed, not a few
of the bright structures seen in the calcium photographs
are here represented by dark forms. The character,
toO', of these forms differs; the hydrogen structures
suggesting storm and stress, whilst those of calciinii
rather are appropriate tOi the processes of quiet precipita-
tion. It should, however, be borne in mind that, where-
as on the explanation here given, in the calcium photo-
graphs we are dealing with t|uite restricted strata of the
sun's atmosphere, tlui hydrogen photograph gives us the
summation oif the effects of many str.ita. For as the
hydrogen line is much narrower than the twoi giant
lines of calcium, it is not possible to isolate small por-
tions of it in the same way.

154

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

Aeroplane

Experiments.

Bv jMajor B. Baden-Powell.

In the last number of " Knowledge & Scientific Xews"
was described the apparatus which I have erected at the
Crystal Palace for givinj,' initial impulse to a man-carrying
aeioplane in order to test the balance and steering arrange-
ments. Since this account appeared many more e.xperi-

very slowly. This difficulty was, of course, soon over-
come by planing away about J inch from the inside of
the rails. Then various trials with different forms of
lubrication for the runners showed difficulties with this
method, and resulted in the application of small wheels
to the sides of the boat in place of the oak runners. The
track itself was also altered, as it was found that the
"take off" at the lower end was rather too steeply in-
clined and detracted from the speed. On June 8 the first
trials were made with a man in the boat, and several
fairly successful descents were made, bolh by Mr.
J. T. C. Moore Brabazon (who has kindly given me

Ready to Start.

Pho:u by Kussell.

ments have been conducted, although we have learnt
what a vast amount of small details need alteration and
adjustment before good resultscan beobtained. Repeated
trials showed that the boat sliding down between the in-
clined rails did not nearly attain the speed which it should
have accomplished according to theory, and it was only
after many days that one cause of this was discovered.
Although the gauge of the track had been carefully tested
on completion, and though the inside of the rails appeared
to be perfectly straight, a subsequent measurement of
the gauge, after the structure had been subjected to many
days' alternate sunshine and rain, proved that the wood
had swollen and warped so that there was a slight con-
traction about halfway down. This was just sufficient
to cause the boat, in its descent, to become slightly
jammed between the rails, but not sufficient to stop its
way, so that to all appearances the apparatus simply ran

most valuable assistance in these trials) and by myself.
The size of the aeroplanes used on this occasion was
insufficient to make a good glide, the total weight of
the apparatus amounting to some 270 lbs., and the area
of the aeroplanes (each 12 ft. by 5 ft. 6 ins.) to only
132 square feet. It was considered desirable to try the
apparatus with this small aeroplane, with the object of
testing the strength of all parts, and in this respect the
results were most satisfactory. The boat, consisting of
rough boards and battens screwed and nailed together,
covered with canvas, stood a lot of very rough usage, and
scarcely suffered at ail from its plunges into the water.
The aeroplanes were of thin cambric, stretched on
bamboos of about liins. diameter at the butt ends. These
were fixed to the boat, but otherwise not stayed or trussed
in any way ; and though they bent upwards considerably
during the descent through the air, pro\ed to be amply

Tr--

KNOWLEDGE & SCIENTIFIC NEWS.

155

Another Glide.

I i'h.oto. by RuiUll.

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

strong enough for the work. By constructing the wings
on this principle, instead of so staying them as to be
rigidly liorizontal, an advantage was gained in that while
on the track the ends were not caught by any side wind,
and yet, while supported in the air, a considerable diedral
angle was formed which gave the desired transverse
stability. On June 13, some larger aeroplanes were
fitted. These were of hexagonal shape (being, in fact,
constructed of old man-lifting kites), and were each of
118 s()uare feet area. The arrangement may be seen in
the last photograph. The lower end of the track had

feet was spread in front of the same hexagonal aeroplanes,
and some fairly successful glides were made, although,
of course, the weight per area (i'24 lbs. per square foot)
was still very excessive when compared to the propor-
tions which previous experimenters with aeroplanes have
applied.

Now that the general arrangement and practical
working of the apparatus has been well tested, it will be
possible to make more exact trials. It is proposed to fit
on an upper aeroplane and other additions to make the
total supporting surface up to some 430 square feet, and

Paddling Ashore After Descent

lPli,>lv ly himell.

now been altered by removing the end support so as to
allow the ends to droop. This is shown in the two
photoijraphs of the apparatus in the air, the boards
having sprung back into the horizontal position after
having been depressed by the weight of the boat. As
the boat left the track, it was canted forward so
that it shot downwards into the water too abruptly
to make a good glide. There was, moreover, on this
ocasion a considerable head wind, which often in-
terfered to some extent with the apparatus attaining
a good speed, but which was not found to be so
serious as might be thought. The usual time of descent
from the top of the track to the take-off was just
3 seconds, being sometinii-s extended to 3^ seconds. On
June 18 further trials were made, after a number of minor
improvements had been effected. The lower end of the
track was now rigidly supported and set so as to be
exnctiv horizontal. A triangular "beak" of iS square

it then seems probable that we may be able to make some
useful glides, full accounts of which 1 hope to send in for
the next number.

Chicago is considering a new machine tO' mend the holes
which all too frequently make their appearance in
asphalt streets. A committee has g^one to Pittsburg
from Chic;igo toi test the device, and if it proves tOi be
able to do what is claimed for it, it will proliably be
adopted in, other cities besides Chicago. .'\spha!t mend-
ing as it is done at present is both a tedious and ex-
pensive job, and a machine which would do' good work
automatically would find a ready field.

lO.!.]

KNOWLEDGE & SCIENTIFIC NEWS.

157

ElectricQLl Ore Finding.

Prospecting by TelepKorve.

In the early part of June, Professor Silvanus Thompson,
F.R.S., delivered a kind of informal lecture on the l>aft-
Williams method of locating metalliferous deposits by
means of electricity : and the system, xyhich has been
the subject of investis;ation for some time, may now be
regarded as having passed from the uncertainty of ex-
periment into the sphere of practical usefulness. Its
usefulness has some limitations, some of which Professor

The Apparatus.

Photo by Burrows.

Silvanus Thompson indicated. It depends for its success
on the difference in electrical conductivity displayed be-
tween the lode of metal which it is desired to locate and the
soil in which the lode is found. Therefore, although the
system has been undeniably successful in locating veins
of galena and of zinc blende, it does not follow that
its success would be equally marked in locating other
metals existing in other matrices ; and it is by no means
certain that the results could distinguish between a small
thickness of rich ore and a number of stringers containing
an equal amount of ore so distributed as to be com-
mercially worthless. Still, the system is capable of
showing great development ; it is at present by no means
a mere scientific curiosity ; and even if it were, it is well
worth attention.

We may best begin its description by an illustration.
If a flow of electricity were to take place between two
points at the top and bottom of this page, the electric
flow would not take place in a single straight line, but

would arrange itself in a number of lines with a greater or
less resemlilance to the lines of force between the poles of
a magnet. ]5ut if on the page a bar of metal were laid,
then the position of thes(> lines would be disturbed— as a
log in a pond would disturb the concentric ripples that a
stone thrown into the pond's middle would otherwise
produce. Similarly, if w'e cause a current to How
between two points on the earth's surface, a held of force
in the earth's crust is formed ; and, as Sir William
Preece showed some twenty years ago, the lines of flow
of the field can be studied with a telephone'circuit con-
nected to earth by portable electrodes. In Messrs.
Williams and Daft's apparatus, the two transmitting
electrodes (between which the current is to be sent) are
earthed usually about 100 yards apart. The circuit in
w'hich they are the two points is fed by an indiution coil
which can deliver a very heavy secondary (Iis(-lKirge into

J'hul.i by Hill

istening to the Telephonic Communicators.

a glass condenser. Two spark gaps — in series and in
parallel — are inserted in the circuit. The breaks are of
two types ; one of the pendulum type, and one which is
designed to give a " make" of any desired length and a
break of unusual abruptness. The receiving (or tele-
phone) circuit, which is to explore the lines of force
created, consists of two telephone receivers, each of 500
to yoo ohms resistance, connecting to the exploring elec-
trodes through a series of parallel switch.

While the current passing between the transmitting
electrodes is suffering its "make and break," the tele-
phones attached to the other or receiving electrodes, which
are immersed in the soil about seventy feet apart, enable
the investigator to " hear " the current as it passes. It
sounds in the telephone receiver like the tap of a wood-
pecker, and it can be heard even when the two telephone
electrodes are immersed in the earth several miles away
from the immersed transmitting electrodes. In practice,
it is not usual to explore at distances more than half a

158

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

mile away from the transmitting electrodes. If the field
is entirely uniform, then the telephones will show, by the
sounds of the tapping in them, that the direction of the
lines of How of the current is approximately in accord-
ance with the theoretical diagrams as shown in text
books.

Now we come to the (juestion of the variations from
the normal, caused by underground deposits of metalli-
ferous bodies. Lodes are electrically divided into two
classes, those w-hich are better conductors than the
enclosing rock, and those which are, comparatively
speaking, insulators. A good conducting lode changes
the shape and intensity of the normal field in a remark-
able manner — elongating it in the direction of the strike.
Waves passing into the lode at great depths are brought
up to the surface. Hence, over the apex of the lode
there is a concentration of energy and a correspondmg
increase of the sounds in the telephones when in the
neighbourhood of the lode. In this way the position of
the lode is easily ascertained, and, on exploring with the
receiving electrodes further and further away, no sounds
are heard whatever, except over the path of the lode.
By moving the electrodes, a point is found where the
sound suddenly ceases in some cases, but is again audible
on moving the electrodes a little further. This point of
equipotential and consequent silence occurs when the
electrodes are so placed that the apex of the lode is mid-
way between them. Absolute silence is not invariably
attained, but in the case of conducting lodes, a diminution
of sound always occurs. If the operator is nearer to the
transmitting base and is receiving some of the normal
waves which are travelling on and near the surface at an
angle to the direction of the lode's strike a cross field is
observed when the lode is between the electrodes, and
the telephones give broken and discordant sounds. With
lodes which act as insulating bodies, the field is never
elongated, but possesses its normal shape. The waves,
on encountering the lode, are brought to the surface of the
-ground on account of their inability to pass through,
and, consequently, are all concentrated in the space
between the apex of the lode and the earth's surface.
When the telephone electrodes — being moved across the
field at right angles to the direction in which it is ex-
pected the ore bodies strike — arrive at a point over a
lode of this kind the increase in sound is sudden and
intense, as might be expected when we consider the
great depths from which the insulating body causes the
waves to be brought.

There are many other ways of examining and testing
the lie of veins and lodes; and the skilled investigator is
able, by a suitable restriction of the electric field and by
adjustment of the potential of the transmitting current, to
apply tests for the depth of the lode. Much has probably
yet to be done in elaborating the -possibilities of this
method, and in simplifying or codifying its applications, so
as to render it accessible in ordinary use ; but of its use
and of its interest no doubt need be entertained.

-rrfe-^r^

The Japanese explosive, Slilmosc, has been said to be
more powerful than oil her dynamite or guncotton.
.Shimose docs not explode on percussion, or by fire,
and is not injured by wctling. When it is exploded,
by a chartje of fulminite, it te.irs a hole gfreator than
would result from the use of a similar quantity of
dynamite, and, unlike th.it substance, its force is equally
exerted in all directions.

ASTRONOMICAL.

The Solar Parallax.

At the last meeting of the Royal Astronomical Society on
June 10, Mr. A. K. Hiaks read a paper on the determination of
the Solar parallax from the measurement of photographs of the
minor planet Eros, taken at the Cambridge Observatory, and
at several other co-operating observatories. The value ob-
tained agreed very closely indeed with that secured several
years ago by Sir David Gill from observations of the three
minor planets — \'ictoria, Iris, and Sappho ; Mr. Hinks getting
8"796, as against Sir David Gill's S"-So2. -At the Academie
des Sciences of Paris on June 6. M. Bouquet de la Grye gave
the result of the measurement of the photographs of the transit
of \"enus, 1SS2, obtained by the French expeditions. These
gave values varying from S"'7S6 to S"'7y2.
* * ■*

An Interesting Variable Star.

Xumbcr 6760 ot ChdiiJIer's Catalogue of X'ariable Stars is a
4th magnitude star, bearing the name of Kappa Pavonis. Its
variability was discovered by Dr. Thome in 1871, and it has
been the subject of a very careful scrutiny during the last
thirteen years by Dr. A. \V. Roberts, of Lovedale, South
Africa. The period of variation is about nine days, and the
range from magnitude 4 to magnitude 5-5. The period of
increase is slightly shorter than the period of decline —
M — m = 4-71 days, whilst m — M = 4-38 days; but when
all the observations are brought together and compared with
the ephemeris, it is seen at once that there is a small syste-
matic v.'iriation in the length of the period — a variation which
goes through all its phases in the course of eight years. This
would be explained if we regarded the variable as travelling in
an orbit seventy times as large as that of the earth, in a period
of eight years, implying that it was revolving round an invisible
primary of a mass 5000 times as great as that of the sun. It
is, of course, possible that this secular variation may be
accounted for in other ways, and may even be purely obser-
vational in character; but it suggests that the star should
make a very promising subject for the most careful heHometer
and spectroscopic observations.

■if -jr *

The Stars of Secchi's Third Type.

The distinguishing feature of the spectra of these stars —
'■ Aiitarian '' stars, as Sir Norman Lockyer calls them, after one
of the brightest examples of the type — is the system of seem-
ingly dark flutings. sharp towards the violet, and shadirg off
towards the red end of the spectrum. Until quite recently
the origin of these flutings has remained without any ^a'is-
factory explanation, and indeed, the question has been debated
as to whether the spectrum should not be regarded as one
consisting parily of bright flutings fading towards the \iolet,
rather than as one consisting wholly of absorption flutings
fading towards the red. Professor .A. F'owler, of l!.e Royal
College of Science, South Kensington, in a papt r recently
communicated to the Royal Society, appears to have given a
satisfactory solution to this long-standing problem. He finds
that the flutings are truly absorption eff'ects, ai d that they
correspond within the possible limits of en or with the
flutin,gs of titanium. The flutings in question co:ne out in the
arc spectrum, if a liberal supply of titanium oxide be used
with a very long arc. As yet Professor Fowler has not been
able to decide completely whether the flutings are due to the
vapour of titanium itself or tothat of itsoxide. It is interesting
to note, especially in view of the correfpondences which
Professor Hale has found in stars of the fourth type to the
lines typical of the spectra of sunspots, that Miss Gierke last
year, in her book " Problems in Astrophysics," definitely

1 1' I V. 1004.

KNOWLEDGE & SCIENTIFIC NEWS.

159

suggested the enquiry as to the presence of titanium ami its
usual associate, vanadium, in stars of tlie third type on
account of the importance of those two elements in suiispot
spectra.

■>r >r -)i-

The Fifth Satellite of Jupiter.

Miss E. E. Dobbin, whilst a student at the \erkes Observa-
tory in the summer of tqo2, undertook, at the request of
Professor Barnard, an investigation of the relative worth of
the orbits deduced for the fifth satellite of Jupiter by Or.
Cohn and M. Tisserand. Later, she undertook a complete
discussion of the problem, using only the observations of
Professor Barnard, in order to secure greater homogeneity.
The observations ranged from 1892 to H)0 5 inclusive, and her
discussion gives the following elements of the orbit : —

(n) = 47"-96i

rfP = 2'''42g daily, or 887"'20 yearly.
I' = 227°-IO, !■—/,= KJi^'So
« = 722"63i6 daily
The most noticeable feature of these results is the smalliiefs
of the eccentricity as compared with that obtained by Dr. t'ohn
and M. Tisserand. Miss Dobbin is doubtful wluthcr the
change is real, and denotes a progressive perturbation wliich
will end in reducing the ellipse to a perfect circle, or is an
accidental one, and the question can only be decided after
another decade of observation or more. The satellite was
noted to be ahead of its ephemeris place in i<)02 and njoj.
This was due to the initial value of the longitutle of the node
being too small by o''7, or i''4, by which amoiml thi' orbit
should be moved forward.

* * *

Orbit and Spectrum of Delta Orionis.

About four years ago M. Deslandres found that Delta
Orionis varied in its velocity in the line of sight, or, to use a
shorter phrase suggested by Dr. Hartmann, was an "oscillat-
ing" star. M. Deslandres deduced a period for it of i-gz days,
and a very eccentric orbit. The star was then placed on the
observing list at Potsdam, and Dr. Hartmann, having obtained
more than 40 plates of its spectrum, has carried out a new
discussion of its orbit ; for which he finds the period, 5 days
17 hours 34 minutes 48 seconds + 17 seconds, and an eccen-
tricity, O' 10334. In other words, the orbit is nearly circular.
But the striking discovery lies here: whilst the lines m general
are characteristically hazy, and show periodical displacements,
one line, the K line of calcium, though always exceedingly
weak, is always narrow and sharp, ctmi takes no part in the
periodic liisjtlacemeiit shou-n hy the other lines. Dr. Hartmann
concludes that this K line cannot be due to the spectrum of
the fainter component of the star, but that a cloud of calcium
vapour must lie between us and Delta Orionis, producing this
absorption. An analogous phenomenon was displayed by Nova
Persei at one time in 1901, and Dr. Hartmann notes that the
component of the solar motion for both Delta Orionis and
Nova Persei almost exactly corresponds to the velocity indi-
cated by these stable calcium lines, implying that in both cases
the intervening calcium clouds are almost completely at rest rela-
tively to the stars from which the elements of the sun's way have
been computed. The distance from us of this cloud cannot be
determined, but its extent might possibly be ascertained by
observations of the K line in neighbouring stars.

* * *

Sunspot Variation in Latitude.

An interesting discussion took [ilace at the last meeting of
the Astronomical Society on June 10 on the above subject.
Dr. \V. J. S. Lockyer recently communicated a paper to the
Koyal Society, stating that " Sporer's Law of Spot Zones was
only approximately true, Sporer's curves being the integrated
result of two, three, and sometimes four ' spot activity track '
cur\'es, each of the latter falling nearly continuously in latitude."
The Rev. A. L. Cortie and Mr. Maunder both read papers on
the same subject, the former showing that the limiting lati-
tudes for large sunspots rose from miniuuun to maximun)
instead of falling in the manner described by Dr. Lockyer, and
that the " spot activity tracks " of which he spoke had no real
existence. Mr. Maunder showed that the Greenwich Sunspot
Results for the last thirty years fully confirmed Spiirer's Law,
and proved that there was but one general zone of tpot acti-

vity in each hemisphere. When e\ery separ.itc spot group
was plotted dowMi according to its solar latitude, it was S(-en
at once that tliere were no such separate downward moving
" spot activity tracks " as Dr. Lockyer had described.

•X- X' »

The R-oya.1 Observator'y', Greenwich.

The annuiil report of the .Vstronomer Royal to tht' Hoard of
\'isitors was read on S.iturday, June 4. The year's record
had been destitute of sensational incidents, the most note-
worthy being the great magnetic storm of October 31-Novem-
ber I. Hut the report records the completion, or near approach
to couiijlction, of a number of most important enterprises.
The publication of the first volume of the " Astrographic
Catalogue" was noticed in " Kno\vi,i:dgk " last mouth. The
photography for the Greenwich section of the " Chart and Cata-
logue " is complete, and the progress made in the observation
of the reference stars for the astrographic plates has been so
satisfactory that it is expected that the work will be com|)leted
next year. The revision of " Groombridge's Catalogue lor
iSio " and the determination of 4000 proper motions therefrom
are complete, and the results are about to be published. Con-
siderable |)rogr<'SS has been made with the measurement of the
photographs of b'ros, taki-u ni njoo and kjoi for the solar
parallax. The rainfall of the year 1903 was 35'54 inches, the
heaviest ever recorded .-it Greenwich during the calendar year,
but the amount of sunshim- registered was a little above the
average, and the number of oliservations made with the transit
circle suffered no diminution through the unprecedentcdly wet
character of the year.

«- * -x-

The Smithsonian Expedition to observe
the 1900 Solar Echpse.

The Smithsonian Institution sent an expedition under Pro-
fessor S. P. Langley to observe the total eclipse of May, 1900,
at Wadesboro, S. Carolina, which was especially interesting in
view of the fact that its leader had observed the famous eclipse
of 1878, two complete solar cycles earlier, at Pike's Peak.
Professor Langley observed with the same 5-inch telescope
that he had used on the former occasion, and says that "the
inner corona was filled with detail, but far less sharp and
definite than he .saw it on Pike's Peak in 1S78. He could not
identify any connection between the coronal structure and the
presence of prominences, while his impression was that the
details contained more ngival curves than straight streamers.
Having in mind the wonderful structure seen with tiic instru-
ment in the clear mountain air 22 years before, the impression
was a disappointing one." This absence of connection be-
tween the prominences and the coronal structure was not
borne out either by visual or photographic observations at
other stations or by the photographs taken at his own camp,
for in his general sunnnary and conclusion Professor Langley
says that "large prominences were present, and these appear
to have been associated with regions of coronal disturbance."
He goes on to say that " the etjuatorial streamers were fol-
lowed on photographs to nearly four solar diameters, and were
then lost by reason of diminished intensity rather than as
appearing to end." This coronal extension, though not so
great as that photographed by Mrs. Maunder in ludi.i in
1S98, seems to be greater than any secured in any of the
other expeditions in 1900. The feature, however, in the
Smithsonian Expedition which excited the most interest
was the use of the bolometer, and though its results were to a
great extent negative in character, they were no less important.
Professor Langley says: "In the bolometric observations the
heating eft'ect of the inner coronal radiations was recognised
and found unexpectedly feeble. The results seem to indicate
a comparative weakness of the infra-red portion of the coronal
spectrum, alike inconsistent with (lie hypothesis that it radiates
chiefly by virtue of a high temperature, or acts chiefly as a
reflector of ordinary sunlight. This, taken in connection with
the appe;n'ance of the corona, seems to support the hypothesis
that the principal source of its radiations is of the nature of an
electrical discharge. The well-known polarisation of itsoiiter
portions, and the pn^sencc of faint dark lines in the outer
coronal spectrum, announced many years ago by J.iussen and
confirmed by the photographs of Perrine in the eclipse of 1901,
prove that a small portion of the coronal radiation is due to
reflected photospheric light. But the photographs of the

i6o

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

coronal spectrum by Campbell in i8g8, and Perrine in igoi'
indicate that the principal part of the coronal light is not
reflected sunlight. Many are disposed to believe the main
source to be the incandescence of particles due to the proximity
of the hot photosphere, but so far as the writer is aware the
spectroscopic evidence is equally in accord with the hypothesis
of a glow electrical discharge. An example of such a discharge
is found in the aurora of the terrestrial atmosphere, but while
we can hardly deny the possibility of its existence in the case
of the sun, the above observations do not seem to the writer to
be conclusive on the point." It seems of the highest importance
that bolometric observations should not be neglected in the
eclipse of iqoj.

ORNITHOLOGICAL.

By W. V. PvcRAFT, A.L.S., F.Z.S., M.H.O.L'., &c.

Breeding of the White Stork a.t Kevv.

Thl pair of white storks {Ciiviiia atlni] at the Koyal Botanic
Gardens, Kew, have again succeeded in hatching out nestlings,
this being the third successive year. In igo2, five eggs were
laid, but from those only three proved fertile, and only one
nestling was ultimately reared. Last year torrents of rain put
a speedy end to the domestic bliss of these interesting captives,
the voung being drowned in the nest. To avoid a similar
catastrophe this year, a roof lias been erected above the nest,
which stands on a mound between the trunks of two large
trees. In spite of every care, however, on the part of the
keepers, and the assiduous attention of the parents, only one
of the four birds hatched out now remains. This, it is to be
hoped, will survive.

* * »

Guinea-Fowl in a R^oma.n Dust-he&p.

A find of considerable interest and importance has just been
made at Silchester in the course of the excavations being made
there by archaeologists. The find in question was the tarso-
metatarsus of a guinea-fowl, which had recently been recovered
from a Roman kitchen midden. That this bird was highly
prized we may gather from the fact that around the leg, during
the bird's lifetime, a bronze ring had been placed, and the
remains of this, much corroded, encircled the bone when
brought to the Natural History Museum for identification.

The value of this discovery lies in the fact that though the
guinea-fowl is believed to have been originally introduced l)y
the Romans, no similar remains of this bird have hitherto been
found in this country. That our domesticated guinea-fowls of
to-day are the descendants of those introduced l>y the Romans
is hardly probable, though at what date they were re-introduced
into our islands, or even into Europe, is unknown.

* * *

Hybrid PheasaLnts.

The remarkably fine series of hybrid pheasants in the
collection of the Duke of Bedford was exhibited by Dr.
Giinther at the meeting of the Zoological Society on June g.
All had been killed, at various times, in the coverts at
W'oburn, and were the results of crosses between the many
different species which have from time to time been liberated
there. Some of these birds were of great beauty, but un-
fortunately they presented characters so subtly blended as to
make it impossible to do more than hazard a guess at their
parentage. That results of considerable scientific value
would accrue from a series of properly conducted experi-
ments made with a view to reproducing the crosses which
these birds suggest, there can be no doubt. It is with a
view to stimulate some such experiments that we now bring
this matter before those of our readers who have the necessary
space and material at their command.

Mr. J. L. Bonhote, who is now engaged in a series of ex-
tremely valuable experiments in the hybridization of ducks,
in commenting on this exhibition, remarked that, judging from
his experience, hybridization tended to reduce vigour, and
that hybrids were either markedly inon-, or conspicuously
/«s, ornamented than their parents. Further, he insisted that
the less coloured birds were the more fertile, and the more

coloured less fertile. As a word of warning in determining
the origin of wild hybrids, he remarked that hybrids tend to
produce the characters of species which were not the parents.

',i '.r 7f

The Eggs of Darwin's R^hea.

The Hon. Walter Rothschild exhil)ited at the Ornithologists'
Club on Wednesday, June 15, the first eggs of Darwin's Rhea
laid in this country. They were laid in Tring Park, and were,
he remarked, relatively larger than those of the Common
Rhea, though the latter is much the larger bird. When freshly
laid they were of a bright green colour, but rapidly faded to a
parchment hue. In their green colour and more polished
surface they further differ from the eggs of Rhea Americana.

* * *

Twite Breeding in North Devon,

Mr. Pearson exhibited at the meeting just referred to the
nest and eggs of the Twite {Linoln iiiontium). This nest was
found on the ground under a low bush on May 5. The
parents were not taken, but were watched within 20 yards of
the nest.

* -X- *

Yel ow-legged Herring Gull at Dover.

Mr. C. N. Rothschild, at this meeting of the Club, announced
the fact that he had seen what he had no doubt was the
yellow-legged Herring Gull (Lanis ccichiiiiuuis) flying in Dover
Harbour on April 18. The conspicuous light yellow legs of
this bird were plainly seen.

PHYSICAL.

An Apparatus for Preventing
Sea-Sickness.

An ingenious apparatus has just been brought out in Ham-
burg, Germany, by Mr. O. Schlick, a naval engineer. This
apparatus is designed both to augment largely the period of
oscillation of the rolling movement of a ship and to diminish
at the same time the amplitude of oscillation, both eft'ects
being based on the gryoscopic action of a fly wheel installed
on board and performing a rapid rotation. The vertical axis
of the apparatus is enabled to perform a pendulating move-
ment in the central plane of the ship. The latter, on account
of the rapid continuous oscillations of the wheel, is rendered
insensitive to the effect of wave-motion, so as to eliminate
practically any rolling movement. As the effect exerted by
the device is rather energetic even with the smallest lateral
oscillations of the ship, there will be no propagation of the
motion. Thus the production of any strong balancing move-
ment will be avoided, in contradistinction to the effects ob-
served in the ease of drift keels, which are not brought to
bear before the rolling movements have assumed a high
intensity. As regards the underlying principle of the appara-
tus, it should be remembered that a rotating body will oppose
to any inclination of its axis a resistance the higher as the
rotation is more rapid, and the weight of the body more con-
siderable. As the forces producing the rolling movement of
a sjiip need not be of an excessive intensity (in fact it is well
known that 20 to 25 men running in proper time from one
side of the deck of a large steamer to the other will produce
rather considerable rolling movements of the ship), the weight
of the apparatus need not eitlier be very high. Mr. Schlick
calculates that in the case of a ship 6000 tons in weight, a
lo-ton fly wheel, 4 m. in diameter, will be quite sufficient.
There will therefore be no diificulty in using the Schlick ap-
paratus on ships of moderate dimensions, such as, for instance,
cross-Channel steamers, where they will largely contribute to
augmenting the comfort of the passengers.
* * *

On Wireless Telephony by means of
Hertzian Waves.

In a recent issue of L<( Kncygia EUclricii, Madrid (May 25,
11J04), Mr. G. J. de Guillen Garcia records some interesting
experiments made by him, iu conjunction with his son. In

KXCnVLEDGF c^ SCIENTIFIC NEWS.

ifii

connection with some wireless telegraphy researches, the son
of the author happened to note that in the tcleplionc of the
Tommasi coherer, located at the receiving station, there was
a "sound difference," which varied in accordance with the air-
gap in the interrupter of the Khumkorff apparatus. This
suggested the idea that a similar apparatus would bo capalilc
of transmitting the human voice to a distance without the
agency of the wire. The e.xpernnents had to be put off for
some time because of the lack of a suitable outfit ; but the
author was eventually enabled, through the courtesy of Pro-
fessor Marcel, of the Barcelona Seminary, to carry out his
idea. The experimental ;irrangenient is a rather simple one.
At the transmitting station there is a Rhumkorff apparatus
3cm. in spark length, as well as the necessary oscillator, a small
antennae, and an earthed conductor. Between the transformer
(i.(., the Rhumkorff" coil) and a small battery of Grenet cells,
there is a special microphone acting both as manipulator and as
interrupter. The autom.itic interrupter of the induction coil is
stopped, while the condenser is used for enforcing the oscil-
lator spark. At the receiving station, there is a Tommasi
coherer, connected to the receiving antenna;, and the earthed
conductor. In a telephone receiver, the noise produced l)y
the Hertzian waves on traversing the coherer is noted. On
approaching the mouth of the microphone and singing or
speaking, even,- sound vibration will be attended by an inter-
ruption in the passage of the electric current through the
primary circuit of the transformer, the number of sparks in the
oscillator thus being varied. The underlying principle shows,
therefore, some analogy with the mechanism in an ordinary
telephone. Any results so far obtained in the reproduction of
singing are said to be quite satisfactory, whereas the rendering
of language leaves much to be desired. The feeble point seems
to be the difficulty of designing a microphone of sufficient
intensity. Mr. Garcia, it is true, has remedied the imperfec-
tions of his apparatus to a certain extent by using a condenser
and augmenting the potential difference. This, however,
could not be driven too far, lest electric arcs be formed.
» * *

On the Chemical Effect of Cathode Rays.

Dr. E. Bose, of Gottingen University, has for two years
past made a close investigation of the simplest possible case
of a chemical action of cathode rays, with a view to ascertaining
whether or not the chemical conversion due to the rays is a
purely electro-chemical phenomenon according to Faraday's
law (see Physiltalische Zeitschyift, No. 12, June 15, 1904). X
solution of caustic potash, saturated in the hot state, was ex-
posed for a long time to the effect of cathode rays in a con-
venient outfit allowing of a large electrolyte surface — in fact,
about 200 sq. cm., being radiated upon intensely, when a
reduction, attended by the formation of hydrogen, was noted.
The amount of electricity absorbed by the electrolyte was
measured with the aid of a hydrogen voltmeter under reduced
pressure, this electricity being drawn off through a platinum
electrode sealed into the bottom of the testing tube. As the
hydrogen present in the vacuum where the discharges took
place was partly dissociated into hydrogen and oxygen, a
mixture of hydrogen and oxygen, containing hydrogen in
excess, was withdrawn by means of the mercury air pump,
and, after the gases due to this dissociation were eliminated
by an explosion, the hydrogen in excess could be measured,
and its pure condition confirmed. Now, in the case of the
chemical effect of the cathode rays following Faraday's law —
i.e., being a purely electro-chemical phenomenon — the amount
of hydrogen derived from the vacuum should be strictly the
same as the one evolved in the voltmeter. A high degree of
accuracy, it is true, was not to be anticipated, on account of
the smallness of the effects and amounts of electricity in
question, but the invariable result of the experiments was in
opposition to the foregoing hypothesis, 1030 and even more
times the amount obtained m the voltmeter being derived
from the vacuum. There must, therefore,be, besides the electro-
chemical action, another chemical effect of cathode rays, due
obviously to the kinetic energy of the cathode ray particles,
this hypothesis being borne out by the theoretical considera-
tions of the author. It is shown that, in the most favourable
case, an amount of hydrogen even 1600 times the electro-
chemical amount would be obtained. But it should be
remembered that, in most cases, the greater part of the
kinetical energy of the rays is simply transformed into heat.

New Self-Recording Barometer.

The new self-recording b.uomrter which Mr. W. II. Dines
has designed, and which is made by Mr. J. Hicks, of ll.itton
Garden, grapples in an original and satisfactory way with the
two problems of the recording barometer — the ditHcully of
registering very small dilferencos, and of ensuring a high
degree of accuracy. The curve traced by the recording pen
is accurate to the one-two-hundredth part of an inch. The
ends aimed at are attained by reducing the friction between
all moving parts, and by the ingenious device of an automatic
correction for temperature. The pen moves with a float in
the lower cistern (the motion being multiplied by a lever) ;
and this float is in the form of a hollow cylinder floating mouth
downwards in the mercury. A rise of temperature lowers the
level of the mercury in the lower cistern ; but at the same
time it makes the float swim higher in the mercm-y, because
the air in the hollow cylinder expands with the same increase
of temperature. The volume of air in the hollow float is so
adjusted as to make the compensation perfect. Another use-
ful device is the addition of what we may call a stationary pen,
which is fi.xed to the frame, and which draws a line of refer-
ence on the reel of paper wound on the clock drum of the
barometer. Any error in spacing tlie chart of the drum, or
any carelessness in placing the chart on the drum, is thereby
rectified, since this line can be taken as the zero line.

ZOOLOGICAL.

The English StodLt.

The English stoat, according to Captain G. E. H. Barrett-
Hamilton, differs from the stoat of Scandinavia — the true
Mustela ci'inineii of Linn;eus — by having the tail coloured
uniformly all round, instead of with the under surface much
lighter than the rest. Moreover, it does not usually turn
white in winter. Consequently, it is regarded as a distinct
race — Mustela (or Puturius) cnniiiea stabilis.

* * *

Habits of African Fishes.

Some very interesting observations, based on specimens
kept in the Aquarium, on the habits of many species of fish
from the Nile are recorded in the Director's report of the
Zoological Gardens at Giza, near Cairo, for last year. Many
of these refer to the long-snouted fishes of the family Morniy-
ridiC, all of which are peculiar to the African riv'ers, and some
of which have a muzzle comparalile to the trunk of an
elephant. In a natural state all these fishes appear to be
thoroughly nocturnal, but in captivity they soon learn to move
about during the daytime, when they will search for the
chopped worms on which they are fed. Specimens of the
long-nosed species, known as Monnyrits kannume, generally
spend the day lying quietly at the bottom of the tank, but
after nightfall become very active, searching energetically
after food. When a light is thrown on them their eyes shine
in a very remarkable manner, sometimes appearing white and
sometimes gleaming red. They have also a curious habit of

swimming tail-first.

* «• »

Classification of Fishes.

Considerable modifications of the generally-accepted
classification of fishes are suggested by Mr. C. T. Kegan in the
May number of the "Annals and Magazine of Natural History.'
The sturgeons and their extinct relatives are, for instance,
regarded as the most primitive representatives of the bony
fishes, and froni this group is derived the bisher of the Nile
and the other members of the now nearly extinct section of
fringe-finned ganoids; while from the latter are descended the
lung-fishes (such as the (jueensland baranumdaand the South
American and African lung-fishes), which have generally been
regarded as constituting a distinct order by themselves.

* * *

Alligators a.nd Crocodiles-

A remarkable dis[)lay of ignorance and inaccuracy has been
recently displayed by a correspondence in the St. James's
Gazette with regard to the alleged occurrence of alligators in

1 62

KNOWLEDGE & SCIENTIFIC NEWS.

[July, {904.

Australia. The first writerstated that these saurians abounded
on that island continent ; this was derided by a second, who
asserted that alligators were confined to America. A third
correspondent correctly pointed out that an alligator is also
found in China, but made the absurd mistake of asserting that
the Australian representatives of the crocodilian order belong
to the genus 1 omistunui, represented solely by Schlegel's
gharial of Borneo and Malacca. The strange thing about dis-
cussions of this nature is that people will rush into print with-
out consulting some standard work on natural history (such as
the " Royal Natural History"), or, still better, the invaluable
series of British Museum "Catalogues," which, although they
afford an absolute mine of authentic information, seem to be
quite unknown to the amateur zoologist. It should, however,
be mentioned that the term "alligator" has a double signation
— a popular and a technical— either of which isperfectly legiti-
mate. In the popular sense it is applied to all the broad-
nosed crocodilians (in the same manner as rooks are generally
called crows), in the zoological sense it is confined to two or
three species of the former, respectively inhabiting North
America and China, unless, indeed, the caimans of South
America are included under the same title.

* * *

Some Giant Fossil Reptiles-
One of the most gigantic of known fossil reptiles has been
hitherto so generally known as Bvontosaurus that it is somewhat
a shock to find that this term, according to Mr. E. S. Biggs, of
the Field Museum at Chicago, must give way to the earlier
Apniosaurus. Of this monster, which attained a total length
of something like sixty feet, two practically complete skele-
tons are known, one of which is preserved in the Field
Museum, and the other in the Museum at Yale College. Of
not less interest are the skeletons of giant toothless ptero-
dactyles (Ptcranodon and Nyctosaurus) which have been
recently set up in American museums, some of these having a
span of wing of fully fifteen or sixteen feet. The former
type, which by some authorities is believed to have had a
curious backward prolongation of the skull, is also peculiar
in possessing a ring of bones in the eye, like birds. Ptero-
dactyles probably seized and held their prey solely by their
beak or jaws, but some of those dinosaurs, or giant land
reptiles, which habitually assumed the upright posture seem
to have used their fore-limbs for this purpose. For in-
stance, the relatively small Oinilliomimiis alius appears to
have raced after its prey, which was firmly gripped by the
long and powerful claws of the front paws.

* * *

A Horn Exhibition.

At the exhibition of sporting trophies recently held at
Berlin, the number of specimens of deer antlers displayed was
very great ; many of them being remarkable for their large
size or symmetry of form. Kaiser Wilhelm was one of the
exhibitors. Medals were offered for the finest specimens.

* * *

Sale of Great Auk's Egg.

A fine specimen of the egg of the great auk was sold the
other day at Stevens's auction rooms for two hundred guineas,
or two-thirds the price realised by an example sold a few years
ago. In 1S38 this egg was bought for £2. while in 1S69 it was
sold for £b^. In 1898, after it had long been supposed to be
broken, it was found among the effects of the daughter of the pur-
chaser. In connection with this subject, it may be mentioned
that a number of skulls and other bones of the great auk have
been recently discovered in an old rubbish heap at Caithness:
one of the skulls being now exhibited in the Geological De-
partment of the Natural History Museum.

* * *

Papers Read.

At the meeting of the Zoological Society held on May 17th,
there was exhibited, on behalf of the Duke of Bedford, a sketch
of a hind and fawn of Pere Davids deer {Ehiphurns tlaviJinnus)
from Hainan — a species previously believed to be now repre-
sented only by specimens living in European menageries. The
fifth of Sir C. Eliot's scries of articles on the naked-gilled
molluscs of Zanzibar and East Africa was read; as was also a
p;iper by Mr. Boulenger on a tree-frog from British Guiana
which carries its eggs on its back. Mr. B^ddard contributed

notes on the anatomy of certain snakes belonging to the
python family; and Dr. G. S. Brady furnished an account of
water-fleas and other minute crustaceans collected in Natal.

• • «

Flying Fish.

" Quill Pen " writes from Las Palmas : " In your number
for April I notice a note on flying fish. I have, during the
last year or two, frequently watched them as opportunity
offered in the South Atlantic and Indian Oceans, and at times
followed the flight of one through a glass, and am inclined to
think the 'wings' may occasionally be used as organs of
flight. When using them as such the fish appears to assume
a more vertical position, resuming the horizontal position
again when using them as .i parachute. I have seen this ver-
tical position assumed twice during a flight, in both of which
progression appeared to be aided by distinct movement of
the wings."

The Nautilus a.nd Flying Fish.

Mr. George Hcnslow writes: "In a note on p. 68 of the
April number are some remarks upon these creatures. I
watched both as carefully as possible through an opera glass
on board ship, and the appearance of the Nautilus at a
distance was that of a white, square sail above the water. As
the vessel approached, the ' sail ' turned out to be the shell
seen endwise. How any motion of the expanded fins of the
flying fish may be effected, it was not possible to observe ; but
the fish can do more than skim in a straight line. They can
rise over an approaching wave, and dart to the side if neces-
sary.

REVIEWS OF BOOKS.

The Analysis of Colour. — The value of Professor A. G. Green's
"Systematic Survey of the Organic Colouring Matters"
(Macmillan) resides in its completeness and its terseness. It
is not a book to be read in an armchair by the pleasant light
of the study lamp: but a manual of severe facts, formulie, and
symbols which present to the chemist, the manufacturer, the
calico printer, the dye merchant, and the patent agent every
accessible means of reference to the composition of the vast
array of synthetic colouring matters that are sweeping away,
by virtue of their cheapness, the vegetable dyes. If we say
sweeping away, instead of " swept away," it is because, as
Professor Green reminds us, the sharp line of demarcation
between the artificial and the natural organic dye-stuffs can
no longer be maintained; and the artificial production of
indigo and the new synthetic products in other groups of
colouring matters are tending still further to obliterate the
distinction. If, indeed, one general conclusion emerges salient
from the tables and records of the organic colouring matters,
it is that there is no finality in the chemistry of colour. The
volume before us consists of two parts, in the first of which
Professor Green deals with the raw and intermediate products
of artificial colour manufacture, extending them so as to
include the most recent methods and material ; and in the
second of which he edits a dictionary of the colouring matters,
based on the German tables of Drs. Schultz and Julius, which
indicates as briefly as is compatible with clearness the com-
mercial and scientific names, the empirical and constitutional
formuljE, the methods of preparation and employment, the
patents, and the literature of each colouring matter. The
first volume on these lines was published ten years ago. Since
that date 59 of the 454 colouring matters then described
have become obsolete. On the other hand, 300 new colouring
matters have been added. These figures do not exhaust,
even in a numerical sense, the change and development in
colour manufacture. Another 16 must be added to the
695 artificial colours to embrace those which are in a tran-
sitional state, between the employment of natural dyes and
the supersession of such d)'es by new syntheses. But beyond
and above these facts is the far more important one that in
the manufacture of colour, no patent, no discovery, confers
lasting profit on its discoverer or owner. A discovery in
industrial chemistry is like a message sent by wireless tele-
graphy; it can be tapped by any scientist in the neighbour-
hood who is provided with the appropriate apparatus.

T>-

lO'M.

KNOWLEDGE & SCIENTIFIC NEWS.

i6-.

Consequently advancement .ind wealth in the manufacture of
what we may for convenience call the " coal tar " dyes are to
be secured not by any isolated success or happy stroke of
fortune, but by continuous application of economical methods,
by unceasing chemical research, and by the cooperative
efforts of a school of chemists. It is because the German
manufacturers have realised these facts and English manu-
facturers have not, that the rewards of the discoveries of
Perkins' mauve, Hoft'man's violet, A. G. Green's primuline,
have not been reaped by England, where they were first made,
but in the long run by the German firms who have applied
to colour making the levers of trained research and organised
equipment. It is for this reason that 90 per cent, of the
patents in Professor Green's tables are of other than English
origin.

In Praise of Gardens. — The most complete justification that
we can find for Mr. John Halshani's " Every Man His Own
Gardener " (Hodder and Stoughton) is in a pass.ige from his
Introduction : " If there be one pursuit that can be commended
as a general recreation, a hobby good for all temperaments,
ranks, and employments, it is gardening. It is a stand-l)y
that will come in with its solid results to fill any hiatus in the
progress of our loftier concerns. If a party go into the cold
shade of Opposition, or a company into li<iuidation ; if a book,
a picture, a play be damned, it is good to be able to shut one's
gates on the mad world, and find one's marrowfats podding,
one's nectarines reddening, faithful to their master's hand,
heartening him to survive the earthquake even as they have
done. There is no vote of censure, no critical cat-o'-nine tails
which can touch that part of his work ; and if he cares to try
the popular suffrage again, he may find that people who have
trodden on his pearls are not by any means incapable of
relishing his peaches." That is not onl\- a piece of extremely
good writing, but it expresses in the fittest terms the reason
for the love which most good Englishmen have for their
garden ; and it is a sufficient indication of the charm of a
charming book. If Mr. Halsham's book were only charming,
that would not, perhaps, be, in the eyes of many people, either
a sufficient excuse for its title, or a sufficient reason why they
should buy it. But it is full of the most practical information
on soils and tilths, cropping, seed-sowing, manures, pricking,
the hotbed, plagues and pests, potatoes and pruning, cut-
tings and bulbs. It is a compendium for the amateur
gardener of town or country, and it is delightful reading for all
who love " the massy-bronzed pears on the south wall, and the
cauliflowers paling from cream to pure white under the green
tent of their leaves " ; or " who balance the gay fulfilment of
the sweet-pea with the green promise of the marrowfat."

Miss Eleanor Ormerod. — In the autobiography of " Eleanor
Oimerod, LL.D." (John Murray), which is edited by Professor
Robert Wallace, of Edinburgh, appear a number of Miss
Ormerod's letters to Dr. Fletcher. In one of them she
humorously suggests that surely it should be recorded of her
that " she introduced Paris-Green into England " ; and in that
phrase is summed up much of the charm, the modesty, and
the persevering usefulness of Miss Ormerod, her life, and her
work. She was born nine years before the accession of Queen
Victoria ; and one might say of her, without fulsomeness or
exaggeration, that she was one of the great women of the
Victorian Era. Beginning with no greater advantages than a
love for living things, she attained a position in which she
ranked as one of the first economic entomologists of the day.
For half a century she was a close student ; for half of that
time her Annual Reports and pamphlets on injurious insects
and common farm pests were beacons which lit the path of a
revolution in agricultural entomology. The real work that she
did is known to thousands of people, and is to be found in
her correspondence with entomologists and agriculturists all
over the world. The less concrete summary of it may be in-
ferred from the impression which she made on her contem-
poraries and co-workers. She was Consulting Entomologist
to the Royal Agricultural Society, Lecturer at the Royal Agri-
cultural College ; medals were conferred on her by scientific
societies, not of her own country alone, but France and
Russia. She was an LL.D. of Edinburgh, and many foreign
societies at home, in the Colonies, and abroad were honoured
by her fellowship. Space forbids that we should attempt
even a brief summary of the main features of her scientific
achievement. For that we mustreferreadcrs to this admirable

biography and autobiography, which reveals Miss Ormerod as
she appeared to all who were privileged to know her, even for
the briefest period, or in the most .accideutal way, as the
kindliest as well as one of the cleverest and most modest
women of our time.

Physical Deterioration. Logical and clearly put, Mrs. A. Watt
Smyth's views on " Physical Deterioration, Its Causes and
Cure" (London: John Murray), miglit also prove of great
instructional value if the right classes of people could only be
made to read them. But in attril)uting the deterioration in
physiiiue of the poorer classes of English people to life in towns
and in suggesting as remedies for it a greater regard for per-
sonal cleanliness, a purer supply of air, milk and other food,
Mrs. Watt Smyth comes perilously near th(' pitfalls of over-
generalisation. As an instance of the snari^ into which this
tendency to generalisation may lead, we may quote one extreme
instance, while admitting that it does not injure the general
argument in favour of leading a hc^althy physical life if proper
physique is to be attained. " The physical and intellectual
i)eauty of the ancient Greeks," says the author, "of which
proofs innumerable have been handed down in their literature
and works of art, resulted . . . from their public games " !
Nothing is less proved or less probable than that the intellectual
success of the Greek nation resulted from anything of the
kind. If it were true, then we might expect the highest intel-
lectual product of our time to arise from the ranks of those
who win Sheffield Handicaps or appear in the incomparable
acrobatic feats of the modern music-hall. To the intellectual
and political success of the Greeks, their geo-political position
was probably the first contributory cause ; and their wise
hvgienic rules of life were a consequence of success already
attained. Similarly, if the factory laws of Great Britain were
perfect; if the abolition of primogeniture made small holdings
likely ; if a greater imaginative sense drove poor English
people to fresh air and pastures new in the Colonies ; if, as a
race, we were more thrifty and less self-indulgent — then the
national physique might improve and public games become a
well-ordered rite. But none of these initial causes, whose
absence we have indicated, is by itself the universal panacea
for good health; and we must decline to believe that even
continued residence in towns is the sole cause of national
physical deterioration. But having thus pointed out what
we think to be the chief defect of this book, that it takes
things too much for granted, and argues from generalities
assumed to be truths, we have nothing but praise for some of
the " cures " suggested. Purer milk is one of them, on which
legislation ought to insist with much greater emphasis ; and
the prevention of children's work in hours when the}' should
be at school is a thing on which we should insist with much
greater emphasis than Mrs. A. Watt Smyth has courage to do.
The abolition of the half-timer, and the insistence that the
years of a boy's or girl's education should be devoted to
education alone — intellectual and physical — these are among
the greatest remedies for the intellectual as well as the physical
stagnation of the masses of the people.

Geology. Mr. W. Jerome Harrison's " Text-Book of
Geology " (Blackie and Son) has reached a fifth edition. A
valuable addition is a table showing the Range in Time of
Invertebrate Fossils. This useful book has been otherwise
revised and brought up to date in accordance with the most
recent additions to our knowledge of rock formation.

Chronology. In " Astronomical and Historical Chronology "
(Longmans, Green and Co.), Mr. William Leighton Jordan has
set himself the task of showing reason for such ;i reformation
of historical chronology as would bring it into accordance
with the method of numbering the years B.C. which has been
adopted by astronomers. In other words, he seeks to prove
that the astronomical method of placing a zero year between
the B.C. and A.D. years is intrinsically superior to the historical
system which places i B.C. and i A.D. in juxtaposition.

Geometry. "Constructive Geometry" (Blackie and Son),
by John G. Kerr, LL.D., is arranged for a first-year's course
in science. Its subject matter is virtually the same as that of
the first three books of Euclid, but from the construction and
examination of drawings the pupil is taught to form ideas
about the properties of lines, points, circles, &c., which it is
hoped will assist his subsequent comprehension of Euclid's
method of dealing with abstract principles.

164

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

Conducted by F. Shillington Scales, f.r.m.s.

Collecting Land and Fresh-Wa.ter
Mollusca.

Some useful hints on collectin.s; land and fresh-water
mollusca were given some time ago in the " American Journal
of Applied Microscopy " (September, 1902), which has now un-
fortunately ceased publication ; and I think an abstract of
some of these hints may prove of service to those who have
not seen the larger article. For land shells a " Ferriss " hoe
is very useful. This is made by getting a small light-handled
garden hoe, and having the blade cut down at a machine shop.
It should be about three inches wide on top, and taper to a
sharp point ; the handle being cut off so that it is as long as a
walking-stick. This makes a most convenient tool for turning
over logs, breaking up rotten wood, and digging around stumps
and among dead leaves. A pair of fine curved-pointed forceps
is necessary for picking up small species. Small glass bottles
should be carried, as the smaller species are apt to get lost in
the dirt and slime if put in the same receptacle as the larger
ones. It is better not to put the small species in alcohol as
they are collected, as they are then killed at once with the
animal more or less extended. If put in a dry bottle and left
a few hours they will withdraw into their shells, leaving the
aperture clear and fit for examination. This is especially
necessary with the Piipidac, where the arrangement of the
teeth around the aperture is a specific characteristic. For the
larger species tin cases of a convenient size for the pocket are
most convenient, and specimens from different localities should
be kept separate as far as possible. For the fluviatile species
a dipper is necessary. This can be made from an ordinary
tin one, by removing the bottom and substituting one of fine
wire cloth. By removing the end of the handle the dipper can
be slipped on to the end of a stick when in use. This is
especially useful for sifting the mud and sand from the bottom,
where so many small species live, which would otherwise not
be found. It will probably be more convenient and thorough
to empty the contents of the dipper into a pail, and to carry
the whole home before attempting to pick out the shells.
The whole mass can then be spread out into the sun to dry
and become friable, after which the shells can be easilv
separated and picked out, an ordinary reading glass being
used if necessary.

The land species love dampness and darkness, and are,
therefore, to be looked for under logs, bark, and leaves in
suitable localities. Many species bury themselves in rotten
logs, which must be broken up with the hoe. Accumulations
of dead leaves around fallen trees, thick grass .and thickets
along the margins of ditches and streams will usually repay
examination, and should be carefully gone over with fingers
and hoe. Coniferous forests are usually quite barren of
molluscan life. Nearly every permanent body of water has
its molluscs, varying according to its character. Some species
are found only in rapid-flowing water, others only in still
water and ponds. The low places in woods, which dry up in
summer, have a number of species not found elsewhere, and
which bury themselves in the mud when it dries. Sand banks
in rivers and lakes have many of the smaller species.

The larger Helices should not be put into alcohol, as this
makes subsequent removal of the animal almost impossible.
They should be boiled as soon as possible, nearly hot water
being useless. A small wire strainer with a long handle is
convenient for holding the snails during this process, and
saves difficulty in fishing them out, with consequent risk of
over-boiling. The time varies according to the size and species,
say from 10 to 60 seconds. If not boiled enough the muscular
attachment is not loosened, whilst, if boiled too long, the
animal is apt to break in two, and thus give trouble in ex-
tracting. Only a few should be boiled at a time, as they
"pull" easier while warm. When boiled, the animal must

be slowly and carefully pulled out, too much haste causing it
to break, leaving the apical whorls in the shell. The curved
points of the collecting forceps serve the purpose, and hooks
of different sizes can be made from safety pins tied to small
wooden handles. A small fine-pointed dental syringe is very
useful in starting the animal, or in case it breaks, in which
case soaking in alcohol for twent^'-four hours usually causes
sufficient contraction of the remnant to enable it to be washed
out by the syringe. After extracting, the interior of the shell
must be well syringed. Any mucous must be removed by
small sponges attached to fine copper wire, or when dry it will
disfigure the specimen. The outside must be scrubbed with
a soft nail or tooth brush, no oil or acid being used on any of
the land shells. In the small species the animal can be left.
After keeping in a dry place for a short time the animal will
retire far into its shell, which must then be put into 25 per
cent, alcohol for a day or two, and then dried in the air, after
which no offensive odour will be left. Either before or after
drying the shells can be cleared by shaking in a bottle with
fine clean sand.

In the operculate species, it is desirable to retain the oper-
cula, or part of it. These are easily removed from the animal
and. after being cleaned, should be put inside the shell, and
the aperture plugged with cotton wool. All foreign matter,
both inside and outside the shell, must be carefully removed
by thorough washing: deposits of lime or oxide of iron on the
water species can be removed with oxalic acid, either by im-
mersion or brushing with a soft brush, but the operation must
not be too prolonged or the shell will be injured.

The larger bivalves can be well washed, and. if necessary,
scraped off with the knife, as soon as found, care being taken
not to injure the epidermis. They can be boiled, when the shells
will open and the animals be easily removed, or the muscles
which hold the valves together can be cut with a thin-bladed
knife and the animal scraped out, care being taken not to break
the edge of any fragile species. All traces of animal matter
must be removed; and, after thorough washing, the valves can
be tied together with string until thoroughly dried, but coloured
twine must not be used as it is apt to stain the shells. Any
incrustations can be removed with oxalic or muriatic acid, but
the specimens must be frequently washed and care used. The
smaller bivalves are best put into dilute alcohol for a day or
two and then dried. If left too long the shells are apt to open,
which looks unsightly.

Both in collecting and cleaning, the specimens from each
locality should be kept carefully separated and labelled, as the
study of the geographical distribution of the mollusca is most
important, and to be of value must be based on accurate
work.

Ground Glass for Diagrams for Lantern
Slides.

There are several photographic methods of making lantern
slides of drawings and diagrams, of which the wet-plate pro-
cess is perhaps the best : but recently it occurred to me to try
a simple method, which has given most satisfactory results,
though I do not remember to have seen it suggested elsewhere.
All that is necessary is to draw or write with a hard pencil — a
6 H for choice — on ground glass squares 3^ X 37, of as finely
ground glass as possible, then to flood the ground side of the
glass with dilute Canada balsam in xylol or benzol. Cover with
an ordinary lantern-slide covering glass, and bind in the usual
way. The only precaution necessary is to avoid imprisoned
air-bubbles, and this is not difficult when a dilute solution is
used. The glasses must, of course, be first carefully cleaned.
The result will be that the ground glass is made transparent,
whilst the pencil lines become more distinct.

Royal Microscopical Society.

May IS, KJ04. The President, Dr. Dukinfield H. Scott,
F.K.S., in the chair. The Secretary called attention to two
microscopes that had been presented to the Society. One was
made by Ladd about 1S64. It had chain movements to the
coarse adjustment and to the stage, the motion being particu-
larly smooth and free from back-lash. The fine adjustment
was effected by a lever hanging from the milled head of the
coarse adjustment, by means of which a very slow motion
could be given. The other instrument was a small portable
microscope, bearing no date, but similar to one made by Cary.
Mr. F. W. Watson Baker exhibited a new objective changer,
made by Watson and Sons, also a device designed by Mr. W.

July, :

KNOWLEDGE & SCIENTIFIC NEWS.

i6^

Rosenhain for mounting specimens of irregular shape, such as
sections of metals, so that the polished surface to be examined
was normal to the optic axis of the microscope, thus obviating
the necessity for a levelling stage. .\ third exhibit consisted
of troughs, invented by Mr. T. G. Kingsford, suitable for fluids
for light filters, or for examining aquatic life. They were con-
structed in various sizes of two flat discs of glass, such as were
used for modern clocks, clipped round the edges by a thin
metal band, leaving a suitable opening at the top. The band
is drawn tight by means of screws near the ends, leakage
being prevented by a lining of rubber strips. These tanks can
be readily taken to pieces for cleaning, and will withstand
sudden changes of temperature. .\ note by Mr. A. A. C.
Eliot Merlin on Mr. \elson"s new formula amplifier was read.
The amplifier consists of a negative lens placed in the rear of
the objective, and was calculated by Mr. Nelson for the author.
to enable him to make some delicate microscopical measure-
ments. With the usual arrangement of a low-power eyepiece
and screw micrometer, the magnification atTorded by high-
power objectives was insufficient to ensure accuracy in .all
cases, and it was not desirable to use more powerful eyepieces
as the spider lines then appeared too coarse. The author
found the amplifier yielded especially good results when used
for micrometrical purposes, and he suggested its application
to students' microscopes for quickly obtaining an increase of
magnifying power. Mr. Xelson's formula for the amplifier
was given. .\ note on Grayson's 120,000 Band Plate, by Mr.
Nelson, was then read. "The band was resolved strongly
by an apochromatic oil immersion J-inch, i'43 N.A., and a
5 ej'cpiece. It was also resolved by a semi-apochromatic
j,7-inch, I-3 N..-\., and 5 eyepiece, and by an old achromatic
water immersion ^V-inch, f2 N..\., but in the last case the
lines appeared to have irregularities. The 90,000 band was
resolved by an apochromatic |-inch, "96 N.A., with some difli-
cultj'. The author remarked that the latest books on physical
optics state that -p~5^-i;-inch is the theoretical limit for micro-
scopical vision. Mr. Nelson stated that ruled lines are more
difficult to resolve than diatoms of equal fineness. He said
the best screen is made from a saturated solution of acetate
of copper, many times filtered, lo which a very small ((uantity
of methylen blue should be added. Sunlight with a Heliostat
was used, and the light made oblique in one azimuth. The
theoretical resolving limit for oblique light may I'oughly be
taken at 100,000 times the N.A. of the objective. Dr. Hebb
remarked that when this plate was exhibited at the Royal
Society's Conversazione some of the lines, though resolved,
appeared weaker than others. Mr. E. E. Hill said this was
due to the objective used having an aperture of only fi N.A.
Mr. Conrad Beck exhibited some flower seeds.

Quekett Microscopical Club.

The 414th ordinary meeting of the Club was held on
May 20, at 20, Hanover Square, W., the President, Dr. E. J.
Spitta, V.P.R.A.S., in the chair. Mr. H. Wallis Kew, F.Z.S.,
gave an interesting account of the False-Scorpions or Chelifers,
illustrating his description with a number of lantern slides.
The Chelifers, or lobster mites, as they are popularly called,
form a distinctive though little studied Order of the Arachnida.
They have been known to science ever since the time of
Aristotle, who classed them with the true Scorpions, a mistake
which was perpetuated for over 2000 years. Of retiring habits
and minute size they may be found in all quarters of the world
in suitable places. Shunning the light they conceal them-
selves under bark, or among mosses and dead leaves, where
they lie motionless until their prey wanders within the reach
of the terrible pedi-palps or forcep-like claws of the second
pair of appendages, which instantly close on the victim, and
transfer it to the cheUcerae, the smaller forceps near the
mouth, by which the victim is held while the juices are sucked
out.

Mr. Kew referred at some length to the habit, peculiar to
this Order, of attaching themselves by the forceps to the legs
of other insects, by which they are transported from one place
to another. Sometimes more than one Chelifer is found on
the same insect, and there are recorded instances of as many
as six, eight, and ten being found so attached. The habit has
been known for over a century and has been recorded from
ever}' quarter of the world, but its object is still one of the
puzzles of science. They do not appear to be parasites, and
the fly appears too large to be a victim, so it has been sug-

gested that they are merely stealing .1 ( In- ip 1 ulr .11 iIh ilys
expense.

Mr. 1). J. Scourfield then gave a description of .Apstein's
Ouautitativo Plankton Net, which liad been devised for the
determination of the exact (piautity of organic life in a given
volume of water. The net h.id been used successfully on the
.Scotch lochs, and a specimen net, with photographs showing
the method of use, was exhibited to the members.

Daphnia and Vorticella.

Mr. Caffyn.of llnrnscy, writes : " I have recently collected
a qu.antity of the Great Water h'lea at Dorking, and practically
every one of them is covered with Bell Animalcules. I think
these are chiefly K/'is/v/is, but there are a few I 'or/uv/Ar. In
Points and Rock Pools. Mr. Henry Scherren says, on page 157,
that it has been stated that thecommtm water-flea never bears
about with it any of the Bell Animalcules that flourish so
luxuriantly on the Cyclo/'S P.; this is stated to be due to a
slimy film. Mr. Scherren goes on to state that he does not
know as to the film l)eing there or not, but he thinks plenty of
the Dciplinia could be found bearing those Vortici-llidans, and
he s.iys that he has lieen told by pond-hunters that they have
seen them in this state. I do not know if the matter has been
definitely proved before ; if not, 1 can certainly verifv it now."

Notes and Queries.

W. N. Bone, Hove.

I am glad that Mr. Warburton's articles on Mites have
decided you to take up the definite study of the Acari. There
is so much work to be done here that is well within the powers
of anyone who is interested in the subject. L'nfortunately,
the literature of the Acari is in a very unsatisfactory and in-
complete slate, and I am afraid I can give you no useful
references other than those mentioned in the articles referred
to. You will find the pages devoted to the subject in •' Car-
penter " useful as a beginning, however. The articles on
Spiders and Mites in the forthcoming volume of the Cambridge
Natural History are contributed by Mr. Warburton, and are
now in the Press. With regard to killing the very smallest speci-
mens, Mr. Warburton tells me that there is nothing better
than boiling water, and that yon must try to straighten the
legs with a camel-hair brush, under a lens. He says chloro-
form increases this ditticulty.
J. C. Miller, Wlllesden.

.As far as I can gather from your description and drawing,
the infusorian referred to must surely be the common Ptira-
nia-cinm, or "slipper animalcule." Its length is generally
about 200 to 260 M (m = 'ooi millimetre, and is the standard
of microscopical measurement). It is of a very much lower
order of life than Hydra, and is really unicellular, though the
radial striations of the pronounced cortex give it a nuflti-
cellularlike appearance. There is therefore no definitely
marked-otf body cavity or enteivn, ihoap^h. it has a "buccal
groove" which leads into a fairly definite mouth, but this
communicates direct with the semi-fluid protoplasm within.
There is a large nucleus, and a smaller luicronucleus, and two
contractile vacuoles, which you may have mistaken for eyes.
When feeding, the animalcule swallows with a sort of gulp,
which carries the particle of food inwards enveloped by a globule
of water, which is gradually absorlx-d later, and any remaining
particles subsequently ejected at a soft place in the cortex, which
may be looked upon as a potential though not a true or
actual anus. It is probably this enveloping globule of water
and the curiously sudden nu^thod of swallowing that you have
mistaken for a " bag." I am sorry to have left your question
so long unanswered, but it has been due to circumstances
beyond my control, as explained last month.
Mlcro-Funjti for Distribution.

By the kindness of Mr. C. H. Caffyn, of Hornsey, I am able
to offer a limited quantity of specimens of micro-fungi, mostly
named, suitable for mounting as opaque objects. Those wish-
ing to avail themselves of this offer should apply without delay,
utilising and complying with the terms of the coupon to be
found in the advertisement pages of the current issue of this
magazine.

'Communications and enquiries on Microscopical matters are invited,
and should he addressed to F . SItillington Scales, "Jersey," St.
Ilariiabas Road, Cambridge.]

1 66

KNOWLEDGE & SCIENTIFIC NEWS.

[July, 1904.

The Face of the Sky for
July.

By W. Shackleton, F.R.A.S.

The Sun. — On the ist the Sun rises at 3.49, and sets
at 8.19; on the 31st he rises at 4.23, and sets at 7.49.
The earth is at its greatest distance from the Sun on the
5th, when the diameter of the Sun is a minimum, beinir
31' 30'-66.

Sunspots and prominences may usually be observed
on clear days, though the change of solar activity to
maximum is proceeding somewhat slower than in recent
cycles.

The position of the Sun's axis and equator may be
derived from the following table ; —

Date.

Axis inclined from N.
point.

Centre of disc, X of
Sun's equator.

July I ..

II ■ ■

21 ..

., 31 ••

2° 36' W.

1° 56' E.

6= 23' E.

io= 35' E.

3° 4'

4° 7'
5^ 3'
5 50'

The jMoon : —

Date.

Phases.

July 5 ••

Last Quarter

,. 13 ••

•

New Moon

.. 19 ••

First Quarter

.. 27 ..

Full Moon

H. M.

54P-m

27 a.m

49 pm

42 am

The Planets. — Mercury is in superior conjunction
with the Sun on the gth, and therefore during the earlier
part of the month he is out of range. Towards the end
of the month he is an evening star, and sets about 8.45
p.m.

\'enus is unobservable, being in superior conjunction
with the Sun on the 8th.

Mars rises only about an hour in advance of the Sun,
and therefore for all practical purposes is unobservable.

Jupiter rises about 11.20 p.m., near the middle of the
month. He is in quadrature with the Sun on the 22nd,
and in conjunction with the Moon at i a.m. on the 7th.
The polar semi-diameter of the planet is iS'-j on the
i6th.

Saturn is coming into a more suitable position for
observation in the evenings ; he rises about 10.15 p.m.
on the 1st, and about S.i5p.m. on the 31st. Near the
middle of the month the planet is on the meridian about
2 a.m.

The apparent diameters of the outer major and minor
axis on the 8lh are 42"-7 and io"-3 respectively, whilst
the polar diameter of the ball is i7"-o.

The planet will be near the ^loon on the evening of
the 28th.

Uranus is becoming more favourably situated for
observation at convenient times, being on the meridian
about 10 p.m. on the 15th. His position on the confines
of Sagittarius and Ophiuchus may be seen on reference to
the chart in the last issue.

Neptune is out of range for observation.

Meteors. — The most conspicuous shower is the 5 Aqua-
rids, which occurs on the 28th ; they are slow moving
and long. The radiant is situated in R.A. 339^ Dec.
S. 11°.

Comet a. 1904 is but a poor object, faint and beyond
the range of small telescopes.

The Stars : —

About 9 p.m. near middle of the month: —
Zenith . Draco, Hercules, Lyra.
South . Corona, Serpens, Ophiuchus, Libra,

Scorpio.
East . Delphinus, Aquila, Capricornus ; Saggit-

tarius to the S.E.; Pegasus and Cygnus to the

N.E.
West . Bootes, Great Bear, Cor Caroli, Leo,

Virgo.
North . Ursa Minor, Cassiopeia. Capella on

horizon.

Telescopic Objects: —

Double Stars: — 5 Serpentis, XW*" 13™, N. 2" 13',
mags. 5' I, 10; separation 10".

^Serpentis, XW" 41"", N. 15^ 44', mags. 3-5, 10;
separation 31".

t Cephei XXH.'' i™, N. 64^ 8', mags. 4-7, 7; separa-
tion 6".

S Cephei XXII.'' 26™, N. 57-' 55 , mags. 4-2, 7 ; sepa-
ration 40". A pretty pair for small telescopes, yellow
and blue. It is also a variable star ; period j'' g*', with a
quick rise to maximum in i"^ g''.

Clusters. — M5 (Libra). A compact cluster situated
about one third of a degree north of the double star
5 Serpentis ; when seen through a pair of opera glasses
it appears like a large nebulous star.

N.G.C. 6633. Cluster in Serpens. About one-third
of the way between e Serpentis and a Ophiuchi (visible
to naked eye).

The Government Plant Bureau of die United States has
just issued sugg'estive information to the American
farmer as to the value of many weeds. Hundreds of
tons of dried weeds are annually sent from Europe (not
much from Eng'land) to the United States, mostlv for
their drug" value. For instance, last year saw ten tons
of dried dandelion roots cross the Atlantic. These
were worth a trifle over twopence a pound, or a total of
some £^30, all of which might be considered as wage
earned in Europe. In the same period, 250 tons of
burdock, used for blood diseases, and worth as much
per pound as dandelion, accompanied them. Ten tons
of poison hemlock, fifteen tons of tansy, sixty tons of
hoarhound, are a few other annual importations of
weeds which have earned the malevolent hatred of the
.\merican farmer. Thorough as ever, the Plant Bureau
gives full directions as to when to gather the various
roots, leaves, or flowers ; how to dr\' them, <tc. " \\'hat-
cver ma}- he said of paternal government," remarks the
Agricultural Economist, " the practical interest which
.\merica takes in the welfare of her greatest industrv' is
proving of very real value to her ag-ricuiturists."

KDouiledge & Selentif je flems

A MOXriILN' JOTRXAL OF SCir.NCE.

Conducted by MAJOR B. BADEN-POWELL and E. S. GREW, M.A.

Vol. I. No.

[NEW SERIES]

AUGUST, 1904.

C Entered at n
Stationers' Hall. J

SIXPENCE.

Contents and Notices. — See Page VII.

ProLcticaLl Meteorology.

I. "TerT\pera.tvire of the Air.

By ^^'II.I.IAM Marriott, F.K.Mct.Soc.

It is curious what vajjue ideas many people have respect-
ing the weather, and of the instrimients eniployetl for
recording its changes. The word " ghiss " is often used
indiscriminately for the Barometer and for the Thermo-
meter; and the word " Barometer" is also occasionally
used to indicate the Thermometer, and vice versa. It is not
supposed that any of the readers of " Knowledge " have
fallen into these errors, but perhaps some information on
meteorological instruments and the results derived from
their observation may be of service.

We are all affected in some way or other by weather
changes, and our feelings tell us when it is cold or warm ;
but for systematic observation of these changes it is
necessary to have a definite standard for comparison, and
for this purpose we use the Thermometer.

It goes without saying that everj'one knows that a
thermometer consists of a fine glass tube with a bulb
blown on at one end, and that it is partly filled with some
liquid, usually mercury or alcohol, which expands on
being heated, and contracts on bemg cooled. The tube
is marked off in degrees so that the changes of the
liquid can be measured on a definite scale. The Fahren-
heit scale is the one used m this country, in which the
freezing point is 32", and the boiling point 21?. ". On the
Continent the Centigrade scale is generally employed, in
which the freezing point is o", and the boiling point 100'.

For meteorological purposes the thermometers should
be sensitive instruments and of the best construction, and
they should be verified at the Kew Observatory in order
that their errors may be determined and the necessary
corrections supplied. In order to obtain the highest and
lowest temperatures self-registering thermometers must
be used. The maximum thermometer may be either on
Negretti and Zambra's or on Phillips's principle. In the
former the tube is bent near the bulb, and the bore
greatly contracted ; the mercury, in expanding, is forced
through this contraction but is not permitted to recede
into the bulb on a lowering of temperature. It therefore
remains at the highest temperature. In Phillips's ther-
mometer a small air bubble divides the mercurial column,
the detached portion remaining at the extreme position
to which it has advanced, thus registering the highest
temperature.

In the minimum thermometer spirit is employed, and

in it theiL- is immersed an index. When the temperature
falls the spirit draws the index along with it, but on
rising again the spirit passes the index, leaving it at the
lowest point to which it iiad been drawn.

In order that these instruments may indicate as nearly
as possible tiie true temperature of the air, and that the
results at various places may be comparable with each
other, they are placed in a .Stevenson screen, with their
bulbs 4 feet above the ground (Fig. i.) This screen,
which is a louvre boarded box painted white, is placed
in the open over grass, and away from walls, i.S;c.

In this country it is the recognized custom to read the
thermometers at <) a.m. and to enter the reading of the

Fiif.

-Stevenson Thermometer Screen.

maximum thermometer to tlje previous day. For all
practical purposes the mean temperature for the day may
be obtained by adding the maximum and minimum
readings together and dividing the result by 2, thus :
Max. 65-0^ min. 43'o" = mean 54'o°. From these two
thermometers we are thus able to obtain for each day the
highest, the lowest, the mean, and the range of tempera-
ture. They do not, however, indicate at what times the
extremes took place, so it is the custom at first-class
observatories to employ photographic self-recording in-
struments for this purpose. Previous to the introduction
of photography it was the practice at the Royal Observa-'
tory, Greenwich, from 1840 to 1847, for the observers to
read the thermometers every two hours, day and night
which was a very laborious proceeding. At the observa-
tory on Ben Nevis hourly observations are regulirly
made, as it is impracticable to employ self-recording
instruments in that extremely damp and cold climate.

i68

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

The photographic self-recording instruments are very
costly, and need special buildings for their equipment,
and so can only be employed at first-class observatories.
By the introduction, during recent years, of the Richard
pattern of self-recording instruments, it is now possible
for observers to provide themselves at a moderate cost
with a small but useful thermograph, which can be
placed in the Stevenson screen, and which will give a
continuous record of the changes of temperature for a
whole week.

Fig. 2.— Summer and Winter Diurnal Ranjie of Temperature.

The following values show the annual diurnal range of
temperature at Greenwich, based on the 20 years' obser-
vations 1 849- 1 868, those with the + sign indicating that
the values were above, and those with the — below the
mean for the day ; —

Mid.

— 3'-4

6a.m

-3^8

Noon

+ 5" I

6 p.m

4- 2 0

I a.m.

— 3-7

7 "

— 2 6

I p.m

+ 5-7

7 "

+ 05

2 ,.

— 40

« ,,

— II

2 ,.

+ 59

8 .,

— 0-8

3 ..

— 4-3

9 ..

-f 0 7

3 ..

+ 55

9 ..

— I -8

4 ..

— 4 "5

10 ..

+ 2 -5

4 ..

+ 4-f'

10 ,,

— 2-4

5 ..

— 44

II ,.

+ 39

5 ..

+ 34

II ,.

— 3 "

It will thus be seen that the temperature is at its

minimum just before sunrise, and attains its maximum
between i and 2 o'clock in the afternoon. Fig. 2 gives
the summer and winter diurnal range of temperature.

We might possibly imagine that the temperature would
progress uniformly day by day from its lowest point in
winter to its greatest height in summer. But such is by
no means the case. The variability of temperature is
very great.

A striking instance occurred in January, 1901. At
Swarraton, near Alresford, Hants, the minimum on the
gth was as low as — i'9°, but the maximum on the loth
was as high as 49'2°, thus showing a range of 51-1" in two
days. In consequence of this great variability, it will be
understood that observations must extend over a large
number of years before the daily irregularities can be
smoothed out. Even 50 years is not long enough to
produce a smooth curve, as will be seen from Fig. 3, which
gives the mean temperature on every day at Greenwich
for the 50 years 1 841 -1890. This Fig. is reproduced
from a paper by Mr. W. Ellis, F.R.S., in the Quarterly
Journal of the Royal Meteorological Society, vol. xviii., p. 238.

Some of the interruptions in the annual march of tem-
perature are very marked. These are not confined to the
south of England, but extend over a much wider area.
Dr. Buchan some time ago investigated the temperature
of Scotland for a number of years, and showed that the
following interruptions occur : —

Six cold periods.

( I July 12-15

Three warm periods. -' 2 Aug. 12-15

I 3 L)ec. 3- 9

These interruptions are, no doubt, associated with cer-
tain types of weather which are accompanied by winds
from definite directions. Generally speaking, the effect
of the wind is as follows: —

N. winds depress the temperature throughout the year.

N.E. winds do the same, except in summer, when their
effect is small.

Feb.

April
May

14
■4

4
5

June
Aug.
Nov.

29-July

6
6

4
II
12

Uc^. Jan.

9 7 13 31 -32 Zt

Feb

March-
es 2J

e 1! 30

May

JxjijLe
S n 23

Jufy

ft 23

K 7i

Sep.

Octc

3 IS 27

Jiau

Dec

' 79 JJ

—

A t<

aA/^i

o^Y

../

K/\

\\l

- \

'^1

55°

(

■i

SO"

' 1

]

1 1

' ! j

■ ' ^ "Vv'

^I^

'. 1

/ '

1 <

i i i

. /

' (

•v

' ' A/V

j \

.c-'^liT ' _ _

.i_*.*VV ^. : : i i

\i\/

V V ^ , /^\ Y ^

1 1 '

A/A/\, // \ '

! L 1 1

'"^Vi^

^^ » V

1 1

•;

i , 1 1

1 1

.. . 1

T "

' ' ' 1

F)?> 3* — Temperature on each day of the year. 1H41-1HQO.

AUGVST, 1904.]

KNOWLEDGE c^^: SCIENTIFIC NEWS.

169

E. winds lower the temperature very nuich in winter,
and generally raise it in sunmier.

S.E. winds do nearly the same, but less iiiarkrdly in
winter.

S. winds raise the temperature much in wintei, hut
scarcely aflect it in summer.

S.W. winds do nearly the same.

W. winds decidedly raise the temperature in winter,
and lower it in summer.

N.W. winds lower the temperature generally, but
mostly in summer.

The most satisfactory way to ascertain the distribution
of temperature over a country is to prepare an isothermal
chart. This can be done by plotting on a map the tem-
peratures at a considerable number of stations, and
joining up the readings of the same values by lines which
are called " isothermals." From an examination of such

the coasts ; the temperature thus not rising to the ex-
tremes which are experienced at inland stations.

The temperature declines wilii increase of altitude at
the rate of nearly i ' in 300 feet ; so, in preparing isother-
mal charts, the temperatures must be corrected propor-

Fig. 4.— Isothermals over the British Isles. Winter.

maps, it is seen that the range of temperature is greater
over inland districts than near the coast. The sea has a
great equalizing effect on the temperature of the air
round the coasts, while inland the ground is warmed up
to a greater extent by the sun during the day, and is
chilled by radiation at night, and so has a more marked
efTect upon the air temperature.

Isothermal charts of mean temperature for the British
Isles fo r the winter month of January and for the summer
month of July are given in Figs. 4 and 5. These are
based on 25 years' observations, 1871 — 1895, ^"<i "^^^
from a paper by Messrs. R. H. Scott, and F. Gaster, in
the Quarterly Journal of the Royal Meteorological Society,
vol. xxiii., p. 275.

The influence of the warm water of the Atlantic is
very clearly manifest in the January chart in the higher
temperatures on the western and south-western coasts
than over the central and eastern districts. In the
summer the sea has a moderating effect on the air round

Fig. 5. Isothermals over the British Isles. Summer.

tionately for the height of the station above sea-level.
The observations on Ben Nevis give a reduction of i" in
270 feet. Experimental observations in the free air are
now being made with self-recording instruments raised
by kites, in order to secure more complete data for deter-
mining the rate of decrease of temperature with altitude.

In the valuable series of meteorological oljservations
which is issued each year from .Stonyliinst Obserxalory
a taljle is published from wiiich it ap|)ears that last
year's weather, un[)ii-asant and surprising as it was,
i)roke few old records at meteorological stations out-
side London. It was a year which, as Father .Sid-
greaves observes, will probaby be known for some time
to come as the " wet year," but it was not the wettest
known. For example, though its rainfall (at .Stony-
hurst) was 58.9 in., and ir in. above the average, it
was more than 3 in. below the 62.1 in. of the year
i8()'i ; and though rain fell on 21,1 days, this was not so
bad as the 319 days out of 365 on which rain fell in
1872. .'\ fact which emerges from Father .Sidgreave's
notes, though it is not coimected with last year's
weather, is that between the highest recorded reading
of the barometer in the last lifty-six years, which w;is
30.507 on January y, 189O, and the lowest, on Decem-
ber «, 1886, of 27.350 in., there is a difference of 3.247
ill. That we may take to be ec|ual to a difference in
pressure on the human frame of not less than a pound
• ind a half to the square inch — not less than a weight of
half .1 ton on the whole human body.

I/O

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

R^a^re Living AnimoLls
London.

By P. L. ScLATER, Dr.Sc, F.R.S.

11.— The Cev-pe Jumping HaLre,

1 1 'cdctcs Cajfcr. 1
This is, indcjci, a rare animal in London, and I be-
li_>ve that the specimen from which Mr. Goodchild has
prepared the accompanying sketch is the only repre-

The general colour of the Jumping Hare is tawny
brown, becoming paler on the sides and almost pure
white beneath. There is also a well-marked white
stripe on the body in front of the thighs. The eye is
large and the ears are rather long and somewhat
pointed; they are thickly clothed with hairs at the base,
though nearly naked at their upper ends. The fore-
limbs are short, with five pointed toes which are usually
carried close to the body and are not very perceptible
in the ordinary attitude of the !i\ ing animal. The hind
legs are strongly developed and much lengthened, the
tarsus being as long as the foot from the knee to the
ankle. There are onlv four toes to the hind-limb, of

II. — The Cape Jumping Hare i/VA/cs Cajjcv).

sentative of the species that has as yet been l^rought
ali\e to this country.

'I'he '■ Jumping Hare " of the Cape Colon v, the
" -Spring-haas " of the Boer farmers, is a well-known
inhabitant of the high interior plains of South .-\frica,
and has attracted the attention of travellers and settlers
there from the earliest times. As long ago as 177S it
was described by the learned Russian naturalist, Pallas,
as Mils cajjcr, and shortly afterwards Buffon, in the supple-
ment to his "Histoire Xaturelle," gave a fairly accurate
account of it as the Grande Gerboisc du Cap, from notes
and sketches furnished to him by Forster. Other well-
known authorities on South Africa who have written of
it are Sparrman, Thunberg, l.c \ aillant, and Rurchell,
the last-mentioned naturalist having carefullv described
it in his "Travels in the Interior of South Africa,"
from observations made in Griqualand West, where, at
his time, it was by no means uncommon.

which the third is the longest, and all are armed with
solid hoof-like nails. The tail is nearly as long as the
body (about 20 inches), .ind is covered with long hairs;
it is brown above and paler beneath, with a large
terminal black patch.

The Spring-haas is nocturnal, or, at any rate,
crepuscular, in its habits. It lives in small communi-
ties on the open veldt, both in the plains and in the
mountain-ranges, and makes large and deep burrows in
the ground, whence it emerges towards sunset, being
rarely seen in the bright daylight. When chased in
the open it proceeds in great bounds like a Jerboa or
kangaroo, for which its highly-developed hind legs are
admirably adapted, and it is even said to move fastei
up hill than down. Its food is entirely of a vegetable
nature, and consists of roots and green stuff of all
sorts. Its tlesh, according to Le \'aillant, is very good
to eat, and in his days was much appreciated b-- the
Hottentots and Caffers.

Al'GUST, 1904.]

KXinVLKDGE cS: SCIENTIFIC NEWS.

171

The Jumping Hare is widely distiibutccl o\cr the
open districts of Soutli .\l'ric:i. In his rccx'nlly-puh-
lished \vori<: on the Mammals of the Cape Colonv and
adjacent lands, Mr. W. L. Schiter tells us that it is
fi>und throughout the higher and drier districts of the
country, extending northwards to Angola on the west,
and the 'IVansvaal and Rhodesia on the east, but not
apparently occurring in Xyasalaiid or Mozambique.
'1 he Si>uth .African .Museum contains examples of this
animal from the Tort Elizabeth, Albany, (iraaf-Reinet,
and Middelburg Divisions of the Cape Colony, and Mr.
Sclater states that it is also found throughout the
Orange Ri\er Colony, the upper part of Xatal, (iriqua-
l.ind West, Beehuanaland, and (ierman .South-West
Africa.

The Spring-haas is \ery rarely met with in capli\ity.
As already stated the specimen now figured is, 1 be-
lieve, the only one ever brought to England alive,
although I have once seen an example in one of the
Continental Zoologic.il Gardens. The Zoological
Society's specimen was presented to them in iSg8 by
Mr. William Champion, F.Z..S., of Durban, Xatal, and
received at the Gardens on March 31 of that year. It
has lived in good health and condition ever since, but is
rarely to be seen outside of its box in the day-time, un-
less the keeper be specially summoned to exhibit it.
. The Spring-haas has been arranged by some authors
among the Murine Rodents and by others ne.ir the
yerboas, to which it exhibits much superficial re-
.semblance. Rut there is no doubt that its strongly-
marked characters require it to be placed in a family
by itself, and Mr. Oldfield Thomas, who has recently
published a general revision of the Order Rodentia, has
put the I'edetidiE at the commencement of the Hystrico-
morphine series, which is probably its most natural
position. Mr. !■". (j. Parsons, the author c f an
elaborate essay on the anatomical structure of Pcdcia
in the Zoological Society's " Proceedings " for i8g8,
has come to nearly the same conclusion.

I'rofessor Joh\ .Milne has made the suggestion that the
displacement of position of the eaj'th's poles, which is of
an irregular kind and which can be traced tO' no known
law, may be due to movements of the earth's crust, and
that, therefore, the magnitude of the change in position
of the poles might be expected to correspond in some
way to the number and frec|uency of gre;it earthquakes.
This theory has been reviewed by M. A. de Lapparent,
w ho was the French secretary at the recent International
Congress of Academies, in an article entitled " The
Wandering Poles," and he finds that the measurements
made by the Meteorological Institute at Rome, under
M. Cancani, corroborate the Milne conclusions in a re-
markable way. Since great earthquakes and earth
tremors result apparently from movements that take
place in the earth's crust — an ocean bed sinking or a
continental mass rising — it seems natural that this
factor should contribute effectively to the change and
distribution of terrestrial mass, and should, con-
sequently, affect the position of the earth's axis, con-
jointly with the annual exterior causes. If this con-
clusion he a correct one, then by observing astro-
nomically the irregularity in movement of the earth's
poles we should be supplied with a mean.s of auscul-
tating the variations in the crust of the earth. The
science might almost be called the new astrology, since
wc might perceive in the apparent motions of the stars
cataclysmic action, pfvssibly of direct influcn<-e on man's
destiny, on the earth.

TKe Later History of
the Horse.

In the January number of A'wcri'/iv/i;!' I gav<' a briel
sketch of the gradual evolution of the specialised,
siiigle-locd, modern horse — or, rather, of all the mem-
bers of the genus Kqnns — from earlii'r ihree-loed and
four-toed mammals ol a more gi'ueralised type of bodily
structure. In that article only a single short paragraph
was devoted to* the spetMal origin of the domesticaled
horse, lack of .space preventing this important, although
exceedingly dillicull, aspect of the subject from re-
rei\ing the attention it deserves. Im the present article
it is my intention to discuss somewhat more fully the
little that is known concerning the history of Eqiius
caballits, as the doimesticated horse and its immediate
wild relatives are tcrnied by naturalists.

Diu'ing the late prehistoric, or .Xcolithie, perio<i, when
|)riir.e\al man. had replaced the rude chipiied Hint im-
plements and weapons of his I'aheolithic forefathers by
a more ad\ancccl type, in uhlili the siuface was ground
smooth and polished, as well as in the Pakeolilhic period
itself, horses are defmitely known to* have been exceed-
ingly common throughout Western and Central Eiu-ope
in a wild state. Thisis fully attested by the abundance
of their skulls, teeth, and bones ini the superficial de-
posits of this country, such as the turbary of the I.ea
N'alley near Walthainstow, and a, gravel-bed at Audloy
End, and in niunerous caves on the Continent, like that
of La Madelaine in France. Although, attempts have
been made toi distinguish twoi species ol true hor.se froni
the prehistoric deposits, it seems practically certain that
all the remains are inseparable from Eqiius caballtis,
as typified by the ordinary domesticated horse of lSlo;rtlv
Western luirope. Careful ex^rmination of' all available
fossil skulls — that is to say, of the specimens in the
British and other Londoiii museimis, as well as the
figures of those from Continental localities given in
scientific works — indicates, moreover, that the Neolithic
and Pakeolithic horse agrees with the ordinary modern
breeds of Western Europe in the complete absence of
any remnant of the depression, in front of the eye for
the reception of the face-gland or larmier, which forms
such a distinctive feature in the skulls of their early
Pliocene three-toed ancestors, the Hipiiarions, and of
which a distinct trace persists in their probable im-
mediate progenitor, the extinct Eqiins sleiioins of the
later Pliocene epoch of this country and the Continent.

Their semi-fossilised skulls and skeletons represent,
however, by no' means the whole of what we know con-
cerning the prehistoric horses of Western Europe.
Primitive man, as represented in this particular instance
by the cave-dwellers of La .Madel.aine, was, fortunately
for us, something of an artist, albeit of an extremely
■ pre-Raphaelite " type, and has left us crude, although
unmistakable, sketches of several of the contemporary
m.-immals he was accustomed to. hunt or tame, among
which are some of the hor.se. In the main, these rude
sketches of the prehistoric horse present a very strong
general similarity of type, and portray a clumsy-headed
and short-limbed brute, with a.n upright or " hog "
mane, and a rough tangled tail, which was probably
only sparsely haired near the root. A couple of sketches
of this type are reproduced in figure i.

172

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

Such Neolithic ariid Paleolithic horses were evi-
dently \evy closely allied tO' the tarpan, or wild or semi-
wild horses, which a century agO' abounded on the plains
of Southern Russia; a neai-jy allied type still apparently
surxiving in the form of the wild ponies — the so-called

\/r^ l^-^i

Fig. I.— Horses sketched by the Cave = dweUers of La Madelaine.

Przewaiski's horse — of the borders of tlie Gobi desert,
which seem tO' be, at most, nothing" more than a local
wild or liaJf-wild race of the domesticated horse. In
these animals the mane is upright or slightly falling
over at the summit, the tail is tliin and scantily haired
at the base, while the head is heavy and ass-like, and the
limbs are short. In cofour the Aloiigoliaii ponies are
dun, with dark brown, manes, tails, and legs,
and frequently with the muzzle whitish; but the tarpan
seems toi liave been a moiuse-coloiured animal. Probably
the prehistoric horse was very similar in. colour to- one
or other of the twO'.

Although most of the sketches ol tlie contem-
poraneous horse left by primitive man indicate animals
of the type referred tO' above, it should be mentioned
that a few of these sketches show a somewhat different
lorm; and from, this fact it has been suggested by some
writers — amoing them Professor K. Munro,* O'f Edin-
burgh, whoi has lately written on this subject — ^Lhat two
distinct forms of ancient wild horse are recognisable in
Western Europe, the one having a smsdler head and
longer limbs than the othei'. In some instances we must
probaljly attribute tliese differences in the sketches o^f
the ancient horse to incapacity on the part of tlie artist;
and this for two reasons. In the first place, none of
the skulls of Neolithic and Pala^ofithic horses that
have come under my notice exhibit aiiiy differences of
the above nature; and, in the second place, judging from
what obtains among mammals at the present day, it
would be in the highest degree improbable that we
sluHild have two closely allied species of true horse
mhabiting the same locality contemporaneously. If,
Dfi the other hand, we credit the artist with having given
correct portraits of two distinct types of true horse,
then it is practically certain that the animals he por-
trayed were domesticated. It should be mentioned,
however, that a sketch from, the Resslerloch Cave,
Switzerland, which has been taken tO' represent a second
species of true horse, is probably intended for the wild
ass.

The question as to whether the horse was or was not
(idnicsticated by the PaheoJithic and Neolithic hunters
of Western Europe is one very difficult to answer.
From the abundance of its remains in the neighbour-
hood of stations occupied by contemporary man, it
seems well-nigh certain that during thel periods in
question the horse formed an important article of food;
and it has been a natural inference that the animal was
kept in a domesticated state by the primitive himter, as
well as pursued for the sake of its flesh. Sir William
I'lovver, for instance, wrote as folloiws :—

" These horses were domesticated by the inhabitants
of Europe before the dawn of history. Caesar found
the ancient Britons and Germans using wax-chariots
drawn by horses."

This view Professor iMunro, in the article already
cited, refuses tO' accept; his opinion being that the horse
was never domesticated by the Pala;ofithic and Neo-
lithic hunters of Western Europe. This opinion is
largely based on the rarity of the remains of this animal
in English " barrows," or tumuli, as well as in the
waste-heaps of the ancient Swiss lake-dwellers. It is
also urged tliat the absence of portraits of mounted
men among the sketches left us by the cave-dwellers
points to the same conclusion.

To the latter objection I do not think much import-
ance can be attached. The rarity of horse-remains in
the tumuli, etc., may be fully admitted as an undoubted
fact ; but since horses, at least on the Continent, seem
tO' have been used for food at this period, the absence of
their bones is, perhaps, just as remarkable whether
they were known only in the wild state, or in botli the
wild and domesticated condition. Here it may be re-
marked that in " Prehistoric Times," Lord Avebury
observes " tliat the horse was very rare, if not alto-
gether unknown, in England during the Stone age."
This, I take it, applies onlv toi the domesticated breed,
since it is quite certain: that the animal existed in a wild
.state in Britain at this time. Nevertheless, the sentence
is apt to be somewhat misleading, and it is for this
reason that it is quoted.

An argument in favour of the domestication of the
horse in Western, Europe has been drawn, from certain
sketches fonnd in Continental caves, which have been
supposed to represent this animal bitted and bridled.
As to the value of this evidence, I do' not feel competent
to offer an opinion, but I doufit if it can be dismissed
by the suggestion (of Professor Munro) that these
sketches may depict wild horses being led in halters or
lassoes to the home of their captors for slaughter as
food. If they be bridled horses at all, I think there
cannot be much donbt that they were domesticated.
My opinion with regard to- the supposed two' types of

* " On the Prehistoric Horses of Europe, and their Supposed
Domestication in Palseolitliic Times." Proc. R Phys. Soc.

Edinb., 1903, pp. 70-104, pi. i.

Fig. 2.— Hog-maned Horse from a Grecian sculpture.

horses represented in other sketches has been, already
expressed.

Another important point in this inquiry is how we
are to account for the origin of the domesticated horses
possessed by the ancient Britons and Germans in

AUGL'ST, 1904.]

KNOWLEDGE .S: SCIENTIEIC NEWS.

^7i

Cjpsar's time unless they were the descendants of the
native prciiistoric breed; for it sccnis scarcely likely
that the Britons, at any rate, could have imported a
foreig'n breed. Unfortunately, \vc know nothing what-
ever with rejfard to the physical characteristics of these
horses. If the ancient British war-horse were an
animal of the type depicted in the Madclaine sketches,
there would be little doubt as to its being an inditjenous
breed, for, as I shall show directly, the domesticated
horses of South-Eastern luirope and Western Asia be-
lonsj'ed to a long-maned breed of threat antiqiiitv.

What we, in fact, really want to know is whether
naturally hogf-maned horses of the tarpan type were
ever domesticated in Europe; and to this question there
seems, unfortunately, no possibility of giving- a decisive
answer.

It has, indeed, been suggested to me that the hog-
niancd horses represented on the frieze of the Parthenon,
which was completed in the year 4;^8 B.C., and those on
the so-called Amazons' .Sarcophagus, dating from the
first century B.C., are animals of this type. .Xnd since
at least most horses in Greek sculptures from about
the year 500 B.C. to the Christian era display similar
hc^-manes, the suggestion appears at first sight very

-'^%

'')

Fi^. 3. — Long-maned Horses of the Assyrian countries.
iFrom Lajard's "Nineveh.")

plausible. I am infofmed, however, by Mr. Cecil Smith,
of the British Museum, that until about the year 500
B.C. the Greek horse is represented with a long flowing
mane. .About the latter date, or, perhaps, a little
earlier, .Athenian vases begin to show horses with hog-
manes, after which such a type becomes predominant,
if not universal, in the sculptures. Etruscan vases, on
the other hand, generally show long-maned horses.
From this, I think, it is perfectly evident th.it the short
manes of the horses on the Parthenon friexe and other
GrfEcoRomaa sculptures are the result f)f cutting. It
follows from this, on the assumption that a long mane;
is the result of domestication, that the Greek and
Etruscan horses belonged to a very ancient breed.

If, now, we direct our attention to the sculptures of
horses from Ximrod, Persepolis, and other ancient
cities of Western Asia, as shown, for instance, on pages
224 and 225 of Vaux's "Nineveh and I'erscpolis "
(1850), and on the plate facing page 334 (herewith re-
produced) of the abridged edition of Layard's
" .Vineveh," we find that they all have long flowing
manes, and tails of such length as to be, in some
instances, looped up. These horses, moreover, ap-
pear to be of a finer and more .Arab-like shape than
those in the Greek sculptures. A similar type of mane
and tail is displayed in some of the horses depicted in
the ancient Egyptian frescoes, as in the one represent-
ing the "Tribute of the .Arvadites " given on page 67

of Gosse's "Ancient h'gypt " (1847). Here the whole
shape and make of tlw horse is decidedly of the Arab
type. In some of the other figures of horses in the
work last mentioned, .is those on page to8, the pendent
character of the mane is not so unmist.ik.ibly dis[)Iayed,
although I think it was the artist's intention to repre-
sent this type.

.As to the date lh.it horses were introduced among
the Babvlonians and .Assyrians, there docs not appear
to he any definite record; but from the f.ut that in the
sriilpturc's the horseman when going to w;ir is always
represented with an attendant on foot leading his horse
and carrying one or more of his weapons, it has been
suggested that riding was a comparatively new art.
In h'gypt the evidence is more satisfactory, as the hoT.se
r", not represented on ;iny of the frescoes antecedent to
til'' i8th dynasty (alxiiil igoo n.c), after which it gradu-
ally becomes more numerous. In all these inst.-mces,
it may be observed, the horse is invariably used only
for war, or in state processions — ^never for drawing
Ijurdens or in agricultural operations.

The ancient Egypti;ins doubtii'ss received their horses
from Assyria and the Babyloni;in countries. .As tO' the
origin of the Assyrian and Babylonian horses, sO'Uie
difference of opinion has prevailed, but it appears tO' me
most probable that they came from some part of Central
.Asia, such as the Turcoman countries. They certainly
were not derived from Arabia, where the horse is
definitely known toi have been a comparatively recent
introduction. Neither, I think, was Africa the place
of origin, as has been suggested by soime, for the very
sufhcient reason that we have nO' evidence of the exist-
ence on that continent of either wild or half-wild true
horses at any period.

From the foregoing it would appear that we have
decisive evidence of the existence in Egypt so long ago
as 1900 B.C., and in the .Assyrian countries (if the above
inferences be correct) at a considerably earlier period,
ol a long-maned breed of Aral>like horse totally unlike
the wild tarpan or the prehistoric horse familiar to the
•,:ave-dwellers of La Madclaine. .Such a breed must have
been the result either of a long ;mtucedent domestica-
tion, or must have been produced from a wild species
furnished with a long mane and t;iil. Probably the
former view is correct so far as the development of the
mane and t.'ii! is concerned, although, as shown below,
it is most likely that tiie I)ree(l traces its origin to a
species distinct from the tarpan and prciiistoric iinrse of
Western Europe.

That such a breed should have been introduced into
CJermany and Britain in pre-Ca-s.-uian times — at all
events, in such numbers as to obliterate all traces of
crossing wilii the wild horses which abinmdcd in those
countries during that period — seems to me in the high-
est degree improbable; rmd I therefore cannot at present
see any valid reason for refusing to- credit the view of
I'iowcr that in Palaeolithic and Neolithic times the
iiuiigenous hog-mancd wild horses were domesticated
I)y the aborigines.

When advocating this view. Sir Williami was, how-
ever, careful to- add that it is " doubtful whether the
majority of the horses existing now are derived directly
from the indigenous wild horses of Western I'^urope,
it being more prob.'ible that they are the descendants of
horses imported through Greece and Italy from Asia,
derived from a still earlier domestication, followed by
gradual improvement through long-continued attention
bestowed upon their breeding and tr.'iining."

In other words, this, broadly speaking, is equivalent

174

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

to saying- that at some early period ai breed of long--
niancd horses was introdi:ced from the cast into Europe,
wiiich resukod in soi nvwiifyinK the original hc>ij--!nancd
stock as to render floavin^^ manes universal; and if this
be the case, we have to attribute a mixed, vr dual,
orit^in to the ordinary, or so-called " cold-blooded "'
horses. Traces of the indigenous ijlood may, perhaps,
be detected in the apparently stouter build of the horses
of the Greek sculptures as compared with those oi the
l^t;;-yptiaa frescoes and Assyrian bas-reliefs.

In comparatively modern times another importation
of eastern blood is definitely known to have taken place,
which, by careful restriction, has resulted in the pro-
duction of the existinij thnrouylibred. The Arabs and
Harbs from which this thoroug-hbred strain origfinated
were themselves, in all probability, the direct unmixed
product of the aforesaid long--ma,ned horses of ancient
Assyria, Babylonia, and Ef^ypt, which we have seen
reason to. believe arose from a totally different stock to
the hog-maned breed of Europe.

With reg-ard toi the ultimate ancestor of the thorough-
bred and its early Asiatic prot^enitor, opinions differ.
IVofessor Ridgeway,* of Cambridge, has reccntl\-
'Suggested that Grevy's zebra {Equiis girvyi), of Somali-
land and North-East Africa, is the prohable ancestor of
the thoroughbred stock. Such a solution of the ques-
tion, will not, however, I venture to. think, commend
ilself for a moment toi competent zoolog-ists, and I need
not," therefore, attempt its refutation,.

From the occurrence in a horse-skull of eastern origin
in the British Museum of a remnant O'f the cavity for
the face-gland of the Hipparions, and of a fainter trace
of the same in the skull of the thoroughbred " Bend Or,"
I have been led to suggest that the thoroughbred and
eastern breeds generally may be derived fro'm an
extinct Indian, species — 'Eiiuhs. sivahnsis — in which this
face-gland was comparatively well developed; and that,
as might have been expected, easterui horses retain
traces of the face-gland cavity, which, as we have seen,
has been completely lost by the prehistoric horses of
Western Europe, as it is by their presumed cross-bred
existing descendants. It must be confessed that the
evidence in favour of this theory is at present slender;
and the examination: of a series of skulls of Arabs and
thoroughbreds is necessary to test its probability. As
it is, all that can be said in its favour is that it affords a
working hvpothesis which accords well with the facts.

In conclusion, I may mention that a correspondent
has informed me that a few years agO' be owned a horse
which showed distinct external traces of the face-gland,
in the form of a well-marked depression in front of each
eye. The horse referred toi was believed to have been an
Argentine, and if this be true, another very curious
point arises. Certain extinct South American horses,
constituting the genus Onohippidium, are characterised
by the enormous size of the cavity for the face-gland,
which was no. doubt functional. From the condition of
their remains they certainly lived till a comparatively
recent date; and it is possible they may have survived
till the Spanish exploration of South .America, for if the
horses seen in Argentina by Cabot in 1530 were indi-
genous (and it is very difficult to. understand how they
could have been introduced'), they must certainly have
been Onohippidiums. Could my correspondent's horse
have been one of their cross-bred descendants?

•"The Origin of the Thoroughbred Horse.'
bridge Phil. Soc . vol cxi . pp 141-14J (1Q03).

I'roc. Cam-

Photography.

Pvire a^rvd Applied.

By Ch.'vpm..\n Jones, F.I.C, F.C.S., &c.

Reversal Further Considered.— There is_ no room
for doubt that the developable condition is of
a more complex character than it is often sup-
posed to be. Sir William .^bney showed some
years ago that the result was not uniform, although the
time of exposure multiplied by the intensity of the light
was constant, if the light intensity varied— that is, the
result of the action of an intense light for a short
period is not the same as that of a weak light for an
equi\alent longer time. The action seems to me to be
comparable to the difference between the few blows of
a heavy hammer and the many blows of a light
hammer, though I do not wish to suggest that the
analogy is complete. The different effects produced by
various forms of radiant and other energy are more
especially noticeable when the action is allowed to pro-
ceed beyond what would produce a normal result, or
when one kind of energy is allowed to follow another.
Professor R. W. Wood has distinguished five " types "
of reversal (better, perhaps, called met/tods of reversal),
namely : (i), ordinary over-exposure, the same light
being allowed to continue to act ; (2), reversal pro-
duced by developing the plate while it is illuminated liy
lamp-light or feeble daylight ; (3), the result of exposure
for a minute or two to light between developing and
fixing ; (4), the Clayden effect, a longer feeble exposure
following a short intense exposure ; (5), reversal pro-
duced by treating an exposed plate with a solution of a
bichromate containing nitric acid, drying, and fogging
by exposure to candle-light before developing. Pro-
fessor Wood also found that Rontgen rays prevent the
reversal of spark images by candle-light, that is, they
negative the Clayden effect ; but that the normal effect
of Rontgen ravs c;ui be reversed by lamp-light. He
arranges the following methods of producing the de-
velopable effect in order : (i), pressure marks ; (2),
Rontgen rays ; (3), light shock (that is, an intense
light acting for a short time, one-thousandth
of a second or less) ; (4), lamp-light ; and finds
that any one can be reversed by subsequent ex-
posure to any other that follows it in the list, but not
Ijy any that precedes it. Mr. Skinner has since ob-
served that radium will reverse electric spark images
(analogous to the Clayden effect), and by prolonging
the exposure actually obtained a re-reversal. It has
been stated that the continued application of Rontgen
rays will not produce reversal. I do not know of any
record of reversal produced by pressure. Perhaps the
first three methods of producing the developable effect
given above are unable to cause reversal of the normal
result produced by each respectively. We want an
experimental investigation of these and similar matters
made under more definite conditions than any th.at have
yet been published.

An Effect of Colour Screens. — A question that has
been mooted occasionally, is as to whether a colour
screen causes the light that it transmits to produce a
greater effect (in the production of a developable
image) than the same light would without the screen,
when for example, the spectrum is photographed.
General Waterbouse recently stated that he had found
a chrysoidin screen to .apparently confer greater sensi-
tiveness to red than the unscreened plate showed.

August, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

175

Now, according to Professor R. W. Wood, the CI:iy-
dcn cflfcot does not depend on wave-length, liiit only on
time and intensity. It is, however, quite likely that the
red screen prevented a feeble general illumination of
the plate, and it appears possible that in this way it
stopped a certain reversing effect, and so caused the
plate to appear more sensitive to the red light. The
various results produced by different causes, as detailed
above, justify such a suggestion.

What is Rezcrscif .' — One may well ask what is it that
is reversed and what is it that is changed in all these
experiments? Silver bromide, silver iodide, gelatine,
and often potassium bromide are present in the film.
It has been suggested, I believe, that there is some
occult combination between the gelatine and the silver
salts, but there does not appear to be any evidence to
support this notion. It has long been known that
silver iodide retards the reversal of silver bromide, and
this is probably the chief if not the only reason for its
introduction intti commeriial plates. If all the experi-
nients on exposure-effect and reversal re-
ferred to were made on plates of known
composition, including simple gelatino-
bromide films, we should certainly get more
information than we have. .A given com-
mercial plate is not always the same. All
makers strive to improve, and improvement
means change. I think, too, that there is
very good reason for doubting Professor
Wood's time-limit of about one-thousandth
of a second for what he calls the " light-
shock " effect. Different illuminants and
different plates might give other time-
limits. My own results that I described
last month, obtained by the use of Wynne's
shutter-speed tester, indicate that a modi-
fication or amplification of Professor
Wood's deductions from his experiments is
necessary. All the experiments and results
here referred to must be regarded as f)nly
initiatory.

Ever-Set Shutters. — An "ever-set" shutter
has the obvious advantage that it is always
ready for use, and that is really the mean-
ing of the word invariably used to describe
such apparatus. It would, however, be
rather more correct to describe them as
never-set, for when an exposure is made the
shutter is not released, but the whole move-
ment of the parts that move is effected by
pressing the trigger or pinching the ball. The
closing is generally effected by springs, in which
case the opening has to be done against the pull of
these springs. Other things being equal, therefore, an
" ever-set " shutter requires more force to operate it
than one that is set by a separate operation and merely
released for the exposure. If the camera is held in the
hand this extra force required means more risk of
movement, and if a pneumatic ball is used when the
india-rubber or its connections are in a poor condition,
it means more risk of failure to operate the shutter.
Rut as is general in such cases, it would be wrong on
this account to condemn " ever-set " shutters as a
class, for as a matter of fact some of them require very
little force to operate them, less, probably, than the
force needed to release some of the shutters that are
" set " by a separate movement. But the fact re-
mains that the same shutter working under the same
conditions will need less force to release it when it is
previously set than to operate it without the previous
setting.

Pea^t and its Mode of
FormaLtion.

By F. E. I''RiTstH, n.Sc, Ph.D.

Whenever plant-remains are deptvsiteti at a rate which
exceeds the rate of decomposition, we get a mass of
semi-decayetl \egetable substaiure of a brownish or
blackish colour and of soft consistency, which we call
peat. Several conditions are necessary to admit of such
a deposit being formed, the most important being in-
sufficient drajnag'e (i.e., accumulation of more water
than is removed) and lack of the ordinary rapid ag'ents
of decomposition. The silting up of a river or of a
lake, or the destruction of an area of forest, may both
lead to the formation of a swamp, which gradually b'^
comes firmer and drier bv the advent of marsh-plants;

Upland Wood. Heather and Bilberry Krowing in Peat formed in the Wood.

as their remains accumulate a layer of peat is slowly
formed. Under ordinary circumstances all plant-re-
mains are rapidly dex;onipnse(l by tiie vario^us organisms
occurring in the soil — ^mainly bacteria, but moulds and
a number of animals also take some part in the process.
This det~ay is especially rapid in warmer climates, inas-
much a.s the growth and activity of the above-mentioned
organisms is much increased at higher temperatures,
and, consequently, peat is almost unknown in the
tropics. In colder regions, however, an abundant
vegetation, together with incompetent drainage, is
generally too much for the agents of decomposition
and, when a layer of peat has once originated in this
way, the process goes on more and more rapidly owing
toi the antiseptic action of the organic acids, formed by
the, part i;d de<;ay of the vegetable substance.

Mr. C. E. .Moss has recently published an interesting
study of the peat moors of the F'ennines. A large
portion of the summits and slopes are occupied by such
moors, which are quite wanting, however, on the steeper
slopes, leading down to the lowlands. Three different

176

KNOWLEDGE & SCIENTIFIC NEWS.

■"Al'gust, 1904.

types of these moors can be distinguished acccrdingf to
the characteristic plants which grow on them; of these
the cotton-grass moors are by far the most extensive
with a vegetation in which one of the two species of
cotton-grass {Eriophorunt vaginaium and E. angusti-
folium) are the prominent forms. The other two types
of moors occur round the edges of the first, one type
being characterised by the abundance of heather
{Calluna Erica), the other by the essentially grassy
character of its vegetation. The cotton-grass moors
are richest in peat, which here extends to a depth of
10, or even 20-30 feet, whilst the other two types of
moor are much poorer in peat, which is usually not as
much as five feet in thickness and often ven.- incon-
siderable. When we come to inquire into the origin of
these peat-moors, all the evidence seems to point to
their being due to the destruction of an original forest.
Numbers of place-names occur on the Pennine slopes

Cotton-grass .Moor in June. Cotton Grass in Fruit.

which indicate a forest, although the onlv trace of it, to
be found now, lies in the buried timber, which has been
found enclosed in the peat. Probably the Roman in-
vasion was the cause of the destruction of a great deal
of this primitive woodland, and the fallen logs probably
serv-ed to dam up a number of the streams, which arose
on the hills, and to otherwise interfere with the drain-
age. The resulting swamps would readily become
populated by bog-forming mosses {Sphagnum, Hypnmri),
which are always present in the upland woods, whilst
the previously existing vegetation would soon be
smothered. From such marshy centres the bogs would
spread out in all directions and probably even come to
occupy ground which was even primarily devoid of
forest, .'\fter some time the remains of the mosses will
have formed a sufficiently consistent layer for the estab-
lishment of tvoical mar.sh-plants, such as the cotton-
grasses mentioned above, and so the entire develop-
ment of such a peat-moor can be traced. On the slopes
of the Pennines the better drainage will not have ad-
mitted of such peat-formation, and, consequently, the
original forest has here again been more or less re-
established. On many of the limestone r(x;ks, which

einerge from the peat, a thin layer of this latter is
found, and here it may actually be seen in process of
formation. The necessary moist basis for the settle-
ment of mosses is in these cases given by a layer of blue-
green or green Algae of a slimy consistency or by the
growth of small Lichens. The mosses grow rapidly
and form a thin layer of peat of a dry character, on
which a slightly divergent flora is usually developed.

The above-described method is no doubt not the only
way, in which extensive pent-areas may develop, for the
silting up of any fair-sized area of water v.ill, given the
suitable conditions, lead to the formation of an exten-
sive moor, and it is by no m.eans necessary that the
silting up should be caused by the destruction of wood-
land. There seems, however, no doubt that the Pennine
moors owe their origin to such a cause, and it would be
no insuperable difficulty to reverse matters and again let
forest cover their slopes. At the present day the huge
area of peat is quite neglected, and there
appears not to be a single peat factorv in the
whole district.

AuMiNii'M does not readily lend itself to
plating, because th; plated metal tends
quickly to scale off, and the defect has been
attributed to the microscopically thin film
of oxide which forms on the surface of the
aluminium, h new method of dealing with
the metal is to immerse it in soluble
fluorides, together with some free hydro-
fluoric acid ; and thus not only to remove
the oxide film but to prepare the surface of
the aluminium for the reception of a plate of
other metal by roughening its surface. The
aluminium is then quickly rinsed and im-
mersed in a bath of zinc and aluminium
sulphates, and while in the bath a film of
zinc is deposited on it by the ordinarj'
methods of electro-plating. Other metals
may now be plated on the zinc. An
electrolytic film of gold will, however,
disappear in the zinc, so that if it is re-
quired to give a gold plating to the aluminium-zinc sur-
face this surface must further be coated with copper.

The German physicist. Dr. Guillaume, has discovered a
new alloy, which he has named Invar. This peculiar
product is formed of certain proportions of nickef and
steel and has the ability to withstand heat without ex-
pansion. When made in a certain way it even con-
tracts slightly on being heated. Its importance is easily
seen when it is considered that all instruments of pre-
cision suffer errors from changes in temperature.
Measuring apparatus, and particularly time-pieces, will
be greatly benefited ; the ability to make a pendulum
certain to stay of a constant length, regardless of
thermal influence, will be regarded with enthusiasm by
astronomers. Other uses have already been found for
it, particularly in surveying apparatus. If it is suffici-
ently reliable to replace the ice bars used in triangula-
tion work, it would effect a great saving in time and
money.

Ai'c.rsT, 1904.]

KNOWLEDGE & SCIENTIEIC NEWS.

177

The •* Panorama "

Military Telescope.

1?V I)k. ALIKEU CiKAUKNU 1 I /.

The field of view of a telescope is necessarily limited,
and whenever the observer wishes to inspect the w hole
of his horizon, lie is compelled to turn round his whole
instrument, while his body has to follow this rotation.
This drawback is obviated in the so-called
" panorama " telescope, where the desired range of

"::1-4 — Q-9-

Fig. I.

vision is secured whilst the eye-piece part of the instru-
ment may remain immovable. It is obvious that the
necessary condition for practical use will be that, apart
from the magnification produced by the instrument,
the observer should receive the same impression of the
horizon as if he viewed it with the naked eye. If,
therefore, an ordinary telescope, either terrestrial or
astronomical, were arranged as represented in figures
I and 2, with a total reflection prism turning round its

-1-^ — e-^

Fig. 2.

vertical axis in front of the objective, in order to obtain
the panorama effect, the image produced would under-
go an angular distortion equal to the angle of rotation.
Anything placed on the top in figure i would, after a
I So" rotation of the reflection prism, appear to lie be-
low ; the image thus being turned also by iSo".
The prism combination to be chosen for the internal
optical construction of the panorama telescope had,
therefore, to fulfil the following conditions : —

1. The image should be erected, simple astro-
nomical eye-pieces being used instead of the awk-
ward terrestrial eye-pieces.

2. The image, whilst exploring the surrounding
horizon, should be kept in position, presenting itself
to the observer as it would appear to the naked eye
looking around.

The Goerz firm has designed several types of
panorama telescopes, and the one described below was
especially intended to be used as a pointing telescope in
connection with guns. The optical elements of this

I iiiiiiiiiKiinui ai e >lu)Wii ill liguic j, wlicie A i.-> a total
retlection prism, B the erecting prism, C the objective,
I) a prism separately represented in figure 4, and () an
astronomical eye-piece.

The rays from the object, penetiating the prism A,
are deflected downwards into the prism U, erecting
them in one direction. After traversing the objective
C, the prism D will produce a lateral change as seen
from figiue 4. The image of the object is, therefore,
produced at the centre of the eye-piece diaphragm E,
in a position corresponding to reality, where it is viewed
through the astronomical cye-piecc in enlarged size.

The prism B has a square cross section, an import-
ant feature being the fact that a rotation by iSo''
around its longitudinal axis will result in the image
being turned by 36o''-, the image thus rotating at twice
the angular speed of the prism. In order, therefore,
to obtain an image corresponding to nature, the prism
H should be made to follow the movement of the prism

Fig. i.

\ at half its angular speed. To secure this effect, the
latter is inserted into the casing U, being fitted below
with a toothing and rigidly connected to the spiral
drum H. The latter may be made to rotate on the
box K, which is screwed inside to the casing V and
outside to the cap G. In the casing V rotates the
tube L, being also pro\ ided with a toothing at its
upper end, and bearing at the top the framing which
contains the prism B, and below the objective C. In
the two toothings the double pinion M engages, the
ratios of gearing being so designed as to impart to the
tube L an angular speed of the same direction as that
of the [)risni A and of half its value.

By acting on a .screw .solidly mounted in the cap (i
arid engaging into the toothing J of the spiral drum II,
the reflection prism .4 and accordingly the prism B, are
turned round, thus producing in the field of view the
characteristic panorama effect.

In the case of the panorama telescope being used
fiom a protected observing stand, the immovable [)osi-

178

KNOWLEDGE & SCIENTIFIC NEWS.

[AucfST, 1904.

tion of the observer will enable him to choose an ob-
serving post of the smallest possible dimensions, thus
decreasing the chance of its being destroyed by the
projectiles of the enemy. It may be used as pointing
telescope for guns in direct or preferably in indirect
pointing.

The design of the telescope has obviously to be
adapted to the special use it is intended for. While

Modern Cosmogonies.

By Miss Ag.nes Clerke.

IX. — The Inevitable Ether-
Ether is the fundamental postulate of physics. Its
existence, nowise apparent, is in all manner of ways

Fig. 5. — The Panorama .Military Telescope.

in a stationary observing post a relatively great field of
view, a strong magnification, and high accuracy in
reading the position of the optical axis are the most
important factors, in the case of an instrument used as
pointing telescope in connection with a field gun,
dimensions as small as possible, light weight, and solid
mounting of the lenses and prisms will be of the ut-
most importance.

implied. The properties that must be assigned to it
are, indeed, arduous of conception. We need the aid
of forced analogies to enable us to realise, even imper-
fectly and indistinctly, the manner in which it dis-
charges functions obviously somehow discharged. But
in the last resort, everything is obscure; if our thought-
borings go deep enough, they always reach the incom-
prehensible.

August, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

179

The original ether was the " quintessence " of tlie
ancients — a kind of matter vaguely imagined as pure
and incorruptible enough to serve for the raw material
of the heavenly bodies, the four common elements being
reserved exclusively for sublunary use. The distinction,
however, eventually broke down. All the spheres,
from the frimum mobile to the \ery surface of our low-
earth, are pervaded by a subtle mode of action, de-
manding for its transmission machinery of a finer kind
than could be constructed out of gross everyday matter.
The phenomena of light, when they came to be atten-
tively studied, imperatively required a medium, uni-
versally diffused, evasive to sense, accessible only l^v
processes of reasoning. Hooke and Newton accord-
ingly brought the ether through the Horn-gate of
dream-land into a region of reality, where it became a
subject of legitimate speculation to men of science.
The task, however, of definitely specifying its qualities
was not taken serioush' in hand until the beginning of
the nineteenth century, when the establishment of the
undulatory theory of light supplied tangible holding-
ground for ideas regarding the vehicle of transmission,
and rendered the ether a fixture of thought.

A great deal is demanded from it. We cannot afford
to set up an establishment of ethers; one factotum must
suffice. Incongruous otlices are devolved upon it. It
has to be Atlas and Mercury in one. It is the universal
supporter and the universal messenger. Whatever
kind of influence, or form of energy, can pass from
world to world, is conveyed by its means. If " action
at a distance " be inadmissible (as Newton himself held
it to be), the pull of gravity must be exerted through a
.medium; and common sense insists upon its identilica-
tion with the transmitting medium of light and electri-
city. That its dictate is actually complied with is
rendered virtually certain by Hertz's discovery that an
electric explosion starts an undulatory disturbance in-
distinguishable, except in scale, from luminous waves;
coupled with the indications derived from Mr.
Whittaker's recent mathematical researches to the
effect that a swifter beat of the same ethereal wings
bears the mandates of gravity. The unity of the medium
may then be regarded as finally ascertained; the com-
plex interactions of sundry different " fluids " need no
longer be taken into account. To provide one with the
capabilities implied by the services we perceive it to
render is, indeed, a sufliciently formidable task.

In popular apprehension, the ether of space figures
as a finer kind of air. No idea could be more mislead-
ing. The elasticity by which air transmits the longi-
tudinal waves of sound is totally different from the
elasticity by which ether propagates the transversal
waves of light. Air yields to pressure; disturbance
hence produces in it undulatory condensations due to
oscillations of the gaseous molecules along the line in
which the audible commotion travels. Ether, on the
contrary, appears to be entirely incompressible; it con-
veys no vibrations directed lengthwise. Now this is
extremely perplexing. We have no experience of a
kind of matter absolutely rigid to pressure, while yield-
ing, albeit with intense reluctance, to distortional
stresses. A jelly-like solid makes the nearest, though
a very distant approach to fulfilling the indispensable-
conditions; and a solid ether was accordingly in vogue
until long past the middle of the nineteenth century.
For a solid, it had very peculiar qualities; th:it, for
instance, of offering no resistance to motion. It was,
in truth, obviously a mere temporary expedient — a
scientific fiction which might pass muster until replaced
by something Cf)rresponding less distantly with the
fundamental fact. M last, on the advent of the

electro-magnetic theory of light and the modified con-
ceptions which it brought in its train, the solid ether
withdrew behind the scenes. Its properties, thoiii;h
inconsistent and unconvincing, h.-ul not been chosen
arbitrarily; they were imposed by the neccessities of the
situation; and when these varied, s[)tH:ulators naturally
had recourse to fresh inventions.

The most plausible is that of a medium neither solid,
liquid, nor gaseous in the ordinary sense, but in the
ideal state of a " perfect fiuid." Out. of such an ether,
Lord Kehin, with exquisite ingenuity, constructed his
" vortex-atoms," which " had their day and ceased to
be." Other ideas now prevail. The present tendency
of physical science," the late Mr. I'reston wrote in
l.Syo,-'- " is to regard all the phenomena of Nature, and
even matter itself, as manifestations of energy stored
in the ether." The more closely we look into the things
around us, the more strongly the persuasion is forced
upon us that what we call ether, electricity, and
matter are really varied forms of one primal substance.
Two comprehensive schemes of molecular physics, rest-
ing upon the basis of this unifying thought, have lately
been elaborated, one by Dr. I.armor, the other by Pro-
fessor Osborne Reynolds. They have nothing in
conmion except the largeness of their synthesis. In
every respect they arc radically unlike, save in regard-
ing the intangible ether as the one material actuality.
Dr. Larmor, however, is not quite confidently explana-
tory. He presents no cut-and-dried theory of the uni-
verse; its haunting mysteries are not ignored in his
efforts to rationalise them. Thus, he is vividly aware
of the diOicullies besetting the endowment of the ether
with the type of elasticity which it is rcognised to
possess. He can only surmise that it results from
particular modes of motion — from " kinetic stability
ensuing upon a special dynamical state. The medium
may thus be thought of as pervaded by "a structure of
tangled or interlaced vortex filaments, which might re-
sist deformation by forming a stable configuration."!
But the details of any such scheme of action are
evidently far too intricate to be unravelled offhand;
what concerns us here is to point out that no simple,
structureless fluid can avail to maintain cosmical com-
munications.

Dr. Larmor's conception of the ether, reduced to its
lowest terms, is that of a " rotationally elastic
medium."; In other words, it resists being turned
round an axis. The forces, however, continually act-
ing upon it are of a gyratory nature; and hence arise
strains, betrayed to our apprehension by electrical
phenomena. Each " electron " is held to be the nucleus
of some kind of distortion or displacement, § and
carries with it, as it moves, a field of force. Out of
these "point charges," material atoms are variously
built up. They are " structures in the ether," encom-
passed by " atmospheres of ethereal strain," not — as
they were formerly taken to be — " small bodies exert-
ing direct action at a distance on other atoms accord-
ing to extraneous laws of force. "11 Obviously, the
new- view brings to the front extremely subtle questions
regarding the nature of " dynamical transmission "!| —
w-hat the propagation of energy essentially consists in,
and by what mechanism it is effected ; and they are,

♦ Theory of Light, 2nd Ed., p. 28.

t Encyclopedia liril.. Vol. XXV., p. 106.

t Report Brit. Asa., 1900, p. 626.

{ Aether and Matter, p. 26.

'i Nature, Vol. LXII , p 453-

■I Larmor. Report lint Ass , ujoo, p. 625.

i8o

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

for the present, unanswerable. Electricity is, on the
theory we are attempting to sketch, positi\e or nega-
tive according to the direction of the originating strain.
.•\ positive electron might be imagined to resemble a
spiral nebula of the right-handed sort, a negative one a
left-handed spiral, or vice versa. The analogy is, per-
haps, fanciful ; yet it helps towards obtaining a mental
picture of objects which, insignilicant and elusive
though they appear, may be the initials and ultimates of
this strange world.

The forces, at any rate, by which it is at present kept
going are evoked ad libitum by the pioneers of modern
research from the ethereal plenum. The actualities of
matter are potentialities in the ether. " All mass," in
Professor J. J. Thomson's opinion, " is mass of the
ether, all momentum, momentum of the ether, and all
kinetic energy, kinetic energy of the ether.* Only if
this be so, he adds, " the density of the ether must be
immensely greater than that of any known substance."
The condition is startling, but in dealing with such sub-
jects, we must not be too curious about anomalies.
They come, as the ghosts appeared to Odysseus in
Hades, at first one by one, then in an awe-inspiring
swarm. Yet, in spite of the perplexities they occasion,
we can discern with growing sureness of insight the
amazing reality of the universal medium. It is, in a
manner, the only reality. For what is manifest to sense
is subject to change. We can conceive that the visible
frame-work of material existence might crumble and
dissolve, like "the baseless fabric of a vision," into
seeming nothingness. But a substance that is inap-
prehensible is, to our limited ideas, imperishable. The
ether is, indeed, the seat of intense activities, wnich lie
at the root, most likely, of all the processes in Nature.
An absolutely uniform medium, however, can scarcely
be imagined to energise or react. Some kind of hetero-
geneity it must possess; and the heterogeneity, pro-
duced, in Dr. Larmor's view, by strains, is associated
in Professor Reynolds's theory, with structure.

The " Sub-Mechanics of the Universe " are here
made to depend upon the fitting together of ineffably
small, ideally rigid grains. A misfit gives rise to
matter, which might hence be defined as " ether out of
gear "; and the misfit can be propagated endlessly from
one range of granules to the ne:;t. This propag.ition
through the ether of an abnormal arrangement of its
constituent particles, without any transference of the
particles themselves, explains the phenomena of matter
in motion. A concrete existence belongs to the ether
alone. It is composed of round, aboriginal atoms, the
diameters of which measure the seven hundred thousand
millionth part of the wave-length of violet light, t
They are packed closely together, yet not so closely but
that free paths are left to them averaging in length the
four hundred thousand millionth part of their diameters.
This inconceivably small relative motion sulfices, never-
theless, to render the medium elastic; is, indeed, " the
only cause of elasticity in the universe, and hence is
the prime cause of the elasticity of matter." The
medium so formed is ten thousand times denser than
water; it exerts a mean pressure of 750,000 tons on the
square inch; the coefficient of its transverse elasticity is
9 X 10-1 (in C.G.S. units); which gives a velocity of
transmission identical with that of light for vibrations
of the same type, while longitudinal waves are propa-
gated 2.4 times more rapidly. The scheme further in-
cludes a plausible rationale of gravity and of electrical
effects; so that there is much to warrant the claim of
its author to have excogitated " the one and only con-
ceivable purely mechanical system capable of account-

ing for all the physical evidence, as we know it, in the
universe. "

The machine, to be sure, lacks motive power; but
that is a want which no human ingenuity can supply.
Its source is obscured in the primal mystery of creation.
And, as regards the preliminary assumptions required
for the constitution of an atomic ether, inclined though
we might be to cavil at them, we should, perhaps, act
more wisely in following Dr. Larmor's advice by ab-
staining from attempts to explain " the simple group of
relations which have been found to define the activity
of the ether. We should rather rest satisfied," he
tells us, " with having attained to their exact dynami-
cal correlation, just as geometry explores or correlates,
without explaining, the descriptive and metric pro-
perties of space.' ; Yet one cannot help remarking
that the properties of space are not ordinarily modified
to suit demonstration, while those of the ethereal
medium are varied at the arbitrary discretion of rival
cosmogonists. In the future, when they come to be
more clearly ascertained, they will, perhaps, form the
basis of a genuine new science. Already, the study of
ethereal physics excites profound interest and atten-
tion. Nor is it possible to ignore the gathering indica-
tions that it will impose qualifications upon principles
consecrated by authority and hitherto regarded as
fundamental. The grand modern tenet of the con-
servation of energy, for example, may need a gloss; it
may prove to be admissible only with certain re-
strictions. The second bulwark of the scientific edifice
is even more seriously undermined. For the " strain-
theory " of atomic constitution necessarily includes the
conception of opposite distortions corresponding to
positive and negative electricity. And the further in-
ference lies close at hand that these, by combining,
may neutralise one another. The coalescence, then, of a
positive and negative electron should result in the
smoothing out ol the complementary strains they stand
for; and there would ensue the annihilation of a pair of
the supposed ultimates of matter. The event might be
called the statical equivalent of the destruction of light
through interference. That its possibility should be
contemplated even by the most adventurous thinkers is
a circumstance highly significant of the subversive
tendencies inherent in recent research. Already, in
May, 1902, Professor J. A. Fleming^ pointed out that
" if the electron is a strain-centre in the ether, then
corresponding to every negative electron there must be
a positi\e one. In other words, electrons must exist
in pairs of such kind that their simultaneous presence
at one pt)int would result in the annihilation of both of
them." The consequence thus viewed in the abstract
finds concrete realisation, if Mr. Jeans's suggestion be
adopted,!! in th;.- processes of radio-acti\ity, which may
consist " in an increase of material energy at the ex-
pense of the destruction of a certain amount of
matter." "There would, therefore, be conservation
neither of mass nor of material energy."

No longer ago than at the opening of the present
century, such notions would have been scouted as
extravagant and paradoxical; now there is no escape
from giving them grave and respectful consideration.
Scientific reason has ceased to be outraged by hypo-
theses regarding the disappearance of mass and the

* Etcctytcitf an I Multcr, p. 51.

t The Stiuiturc of llic Viiiveisc, Kedu Loctur

I Natnic. June, Vol. I, XII, |i. 451.

§ Pi'Oiiiiliiigs Royiil Inititutinn, Vol, W'll, jj

II Nalure, Vol. LXX, p. 101.

e, June 10, 1902, p 14.

August, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

181

cle\elopmcnt of energy. Mass and energy may, alter all,
be interchangeable; they are, at any rate, kept less
rigidly apart in our nieclitations than used lornierly to
be the case. Xor can we assert with any conlklence
that partial subsidences into, or emergences Ironi, the
surrounding medium is for either a slieer impossibility;
the universal framework, on the contrary, presents it-
self to us in the guise of an iridescent fountain leaping
upward from, and falling back towards, the ethereal
reservoir.

To the very brink of that mysterious ocean the
science of the twentieth century has brougiit us; and it
is with a thrill of wondering awe that we stand at its
verge and survey its illimitaole expanse. The glory of
the heavens is transitory, but the impalpable, invisible
ether inconceivably remains. Such as it is to-day, it
already was when the t lat Lux was spoken; its
beginning must liave been coeval with that of time.
Nothing or everything according to the manner in
wfiich It is accounted of, it is evasive of common
notice, while obtrusive to delicate scrutiny. Its nega-
tive qualities are numerous and balliing. It has no
effect in impeding motion; it docs not perceptibly
arrest, absorb, or scatter light; it pervades, yet has
(apparently) no share in the displacements of gross
matter. Looking, however, below the surface of
things, we find the semi-fabulous quintessence to be
unobtrusively doing all the world's work. It embodies
the energies of motion; is, perhaps, in a very real
sense, the true ■prtmum mobile ; the potencies of matter
are rooted in it ; the substance of matter is latent in it ;
universal intercourse is maintained by means of the
ether ; cosmic influences can be exerted only through
its aid ; unfelt, it is the source of solidity ; unseen, it is
the vehicle of light ; itself non-phenomenal, it is the
indispensable originator of phenomena. A contradic-
tion in terms, it points the perennial moral that what
eludes the senses is likely to be more permanently and
intensely actual than what strikes them.

Pure science has usually, at all times and in all coun-
tries, been poorly paid, and we are reminded by an
article by Father Tondorf in Popular Aslronomy that the
great Repler had to supplement pure astronomy by
doubtful astrology. Kepler did not believe in astrology.
" Your error," he writes to a friend, '' is one common to
the greater part of the school of doctors, who fancy
that fortunes drop from the skies. Naught conies thence
save light ' — but he had to supply horoscopes in order
\.y supplement an insufficient income. Some of those
v.ho applied to him for predictions from the stars were
half convinced with him tluit Astrology wiis the '" foolish
little daughter of Mother .Astronomy," as witness the
following letter to Kepler from Zeheutmeyer, secretary
of Baron von Heberstein : " You are a man busied in
scientific investigation and in reading the future in the
stars. Please inform me whether these heavenly bodies
indicate anything in particular regarding this section of
tiie country. The 15aron, my dear sir, is extremely
anxious to give you, a man of such authority, a say in
this matter. 1 am far from ignorant of your conviction
that nothing can be foretold with certainty ; in fact,
that the science of a.strology is a vague and tre^icherous
art. However, you know how man hankers after news,
and how he would have nature forewarn him of the
future. I pray you, then, send me something. Harbour
no fear. Wliat you send shall be considered strictly
confidential."

Sunspot VaLriaction in
Latitvide.

I>V W'll.lIAM |. .S. I.IX K^ li.!, M..\.

.1).

In the .\slronomiral Xotes m this journal lor July relcr-
ence was made to a \cry l)ricf discussion which took
place at the Royal .'\slrononiical Society on June 10 on
the abo\c suljject. As this note seems to suggest that

M\\\

. 1870.

/A
_r<:_ A^ I860

lLL yil 1681.

<^^

I /

}^\

- -/ ', I L

' I

;

,;^

^y^- ^

■ 1

1
1 1

,1^ I8B3

1684.

1865

188ft
1667

"~^^

..^^

1688

1889.
1690

1661

1865

1672

1886

40 20 - 0 - 10 40

40 30 20 10- 0 MO 20 30 10
S N

Pijf. I. — The di)tted lines indicate Hijc- 2.— 5nme typical curves,

the loci of miivenient of the ind.- showinif the distribution of spotted

V idual maxima of spotted area or area per 3^ /.ones.

the ■:! ot-activit'j tiiUki,

tlic results I have puljlished (Roy. Soc. I'roc. vol. 73,
p. 142) are entirely in disagreement with (hose set forth
by Father Cortic, perhaps I may be permitti^d to make
the following remarks : —

Mention may first be made as to tin- meaning of the
term " spot-activity track," which 1 think has been
somewhat misunderstood by both I'alluT Cortie and
.Mr. .Maunder. The accompanying figure (Fig. i),
whi<-h includes a complete sunspot cycle, may, per-
haps, help to make this term clearer. ICach jjair of
cur\es above each horizontal line represents the varia-
tion in latitude of spotted area throughout a year as
determined by summing up the spotted area for each

l82

KNOWLEDGE cSj SCIENTIFIC NEWS.

[August, 1904.

zone of 3° in width, using the values for each degree
of latitude as published by Greenwich Observatory. A
ghmce at those curves will show : —

(ti) that many of them have more than one in-
dividual maximum;

(/') that these individual maxima do not ahvajs re-
main from year to year in the same position as re-
gards latitude (though sometimes they do maintain
the same for two, three, or four years together as
can be gathered from the curves in my paper).
Ky joining up these maxima from year to year there
appears to be a general drift from high to low lati-
tudes; that is, the positions of the regions (zones) in
which the spotted area is greatest change from year
to year in a direction towards the equator. These
lines of drift of the individual maxima, or their loci of
movement towards the equator, are the ipot-activiiy
tracks. They are not tracks on the solar disc as seems
to have been inferred.

.\n argument greatly in favour of this method of
treating these multiple points of maxima indi\idually
is that we have a needed explanation of the anomalies,
pointed out by Spoerer and Hraun, of the mean latitude
curves. The accompanying figure (Fig. 2) will give the
reader some idea of the distribution of spotted area for
several selected years, showing that although the
spotted area extends over broad zones there are
prominent subsidiary maxima included in those zones
wliicli should not be neglected. Against each of these
pairs (if ciu'ves the date of the nearest sunspot maxi-
mum (ir minimum has been inserted.

The writer of the note is quite in error when he says
that Father Cortie showed " that the limiting latitudes
for large sunspots rose from minimum to maximum in-
ste;id (if falling in the manner described bv Dr.
l.ockyer. " Father Cortie rather corroborated than
op[)nsed my result. .-\s a matter of fact I pointed out,
as one of the main results of my investigation, that out-
bursts of spots in high latitudes are not restricted
simply to the epochs at or about a sunspot minimum,
lull occur even up to the time of sunspot maximum,
and further, that there was a tendency after a sunspot
minimum for each successive spot-activity track to
make its appearance in latitudes higher than those just
preceding it. This result I considered important since
it was not in harmony with that which would be ex-
pected by Spoerer's Law, i.e., that the highest spot
latitudes occur about the time of sunspot minimum
when a new cycle is in process of commencement.

"Notes on the Composition of Scientific Papers " (Macmillan
and C'o.i.liy Dr. T. ( litiord .All butt, Ivigius I'rufessor of Physics
at Caiiibridt;e, have been compiled in the hope of improving
or forming the literary style of scientiiic students. In the
course of the year I'rofeasor AUbutt tells us, in his humorous
and engaging preface, he has to read some hundred theses
for the degrees of M.B. and M.U. — '"in composition a few are
good, the greater number are written badly, some very ill
indeed," so as " to obscure, to perplex, and even to hide or
travesty the sense itself." It is difficult to say how far a sense
of style can be imparted, but Professor AUbutt gives sound
and excellent advice on the use of words and the construction
of sentences, which might with advantage be taken to heart by
others than scientific students.

"The Honey Bee" (Houlston and Sons), by T. W. Cowan,
F.L.S., F.G.S., F.R.M.S., the well-known authority on bee-
keeping, has reached a second edition. This comprehensive
little volume, with its elaborate diagrams and illustrations, is
valuable alike to the student and the bee-keeper.

The Birth of Crystals.

Tim researches of Dr. Otto \on Schron, Professor of
Pathological Anatomy in the University of Naples, ga\ e
meaning some ten years ago to the expression " the
living crystal." He showed that living matter, largely
albuminous in character, takes the crystalline form,
and, while still living and crystalline, obeys so many of
the laws and manifests so many of the properties of
inorganic crystallisation that its crystalline character
may be said to be established. F'rom these experi-
ments he drew the inference that crystallisation in its
terrestrial origin was a manifestation of life — of vital
energy. In short, that a crystal grew for the same
reasons that a plant grows, or the brain grows, or an
amceba grows ; that the vital forces stirring the one
are no more than a different form of the forces that
develop the other. The "living crystal," the "vital
crystal " which, for example, he discovered as one of
the products evolved by various of the bacilli that he

Alum in the Precr>stalline .state, showing appearance of lines
of direction marking future axes. Enlargement, 280.

examined, became thus, in his theory, the bridge be-
tween what had heretofore been called living matter —
animal and vegetable — and dead matter — mineral. The
first crystals which set him on the road to this theory
were the crystals of the .Asiatic cholera bacillus, which
he examined as long ago as 1886. They were long,
needle-shaped prisms. Other bacilli examined exhibited
distinct crystals of different forms. The bacillus
siihtiln, for instance, formed bayonet rhombs ; the
biiallus icimaformis hexagonal prisms ; the tubercle
bacillus develops square rhombs ; anthrax, elongated
rhombs ; any given bacillus being immediately identi-
fied by its crystal, which never varies in the shape
assumed in its original formation. These objects are
perfect crystals in form ; yet, as anyone may see, they
are alive, and their life, their motion, and their repro-
duction are as \isible and undoubted as their death
when it ensues is undoulited. Their death occurs when
all the li\ing matter which originally formed part of the
cryst.il has eliminated itself. On death they become
the crystals th.it we know, ordinary mineral crystals.
.Such were the beliefs and theories, rather freely
stated, of Von Schron ; and their interest at the present
time lies in the re-statement by MM. F. di Brazza

August, 1904.]

KNOWLEDGE c<^ SCIENTIFIC NEWS.

183

and P. Pirenne in the Revue Sciciitifique, of the hypo-
thesis that crystals have a kind of life, of a lower grade
than that of plants, but still real life. These writers
found tlieir theories on phenomena observed under a
microscope during the growth of a crystal from a
solution. These phenomena have several features in
common with the growth of a living cell.

^M-:-^i'

-J'

Salicylic Acid in Precr>stalline state, stiouinjr birth of multi-
polar cellules resembling nerve cells. linlarj^ement, 2'Su.

If we dissolve salt in water until the liquid is
saturated and then modify the conditions by lowering
the temperature, we see crystals of the dissolved salt
appear. The process apparently simple, and depend-
ent on easily-stated chemical and physical laws, ap-
pears none the less to originate in a series of

Lsrge Petro-cellule uf Quartz, showing two protoplasmic sub-
stances, and nuclear petroblast. Enlargement, 750.

phenomena that have a remarkable similarity to vital
phenomena. .■\ccording to MM. di Brazza and
l^irenne : "At the beginning of the crystallisation a
tiny globule is seen to be differentiated from the uni-
form mass, being easily recognisable on account of its
difference in refractive power. Studied closely, this
globule shows within it a slight ' petroplasmic net-

work,' which shows an analogy with the formation of

animal and vegetable lells

"Then are seen appearing in the lulwnrk sni.ill ob-
scure points called ' [JotrobLists, ' uliicli, wlu-n (ilis<i\i(l
under high magnilying power, srcni t(i he at llu- rviilrc
of a dark substance c;ilk-d ' dculcrolillioplasni,' and on
the periphery of another cIcaitT sulislanrc nanu-d bv
\'on Schron ' prulolitlioiilasm. ' I lie lunn.itiDn nl Ihr
crystal results from these two substaiu-es. . . Crystals
have different origins, but . . . the pefropl.ismic kind
is bv far the most coniinon. In the stiifc l)f1\M'iii the
two substances constitiiling the petroblast, the globule
changes form by an annulai' enl.irgenieni ; the rins; then
is deformed and ,111 angle is iormed \\lii<h I'rcjlessor
von Schron calls the ' priniilix e doiuinaiil anisic,' be-
cause it gives the direction ol llie lutm'e civstal. .Soon
a second angle lornis cjpposile the first, called llie
'diagonal angle' MnalU llu- meeting-points of llie.se
two opposed angles lorm new .•ingles c.illed 'second-
ary.'

llie ervstal, u liose loiin.ilive phases \\i- li.i\e llms
stuilied, can move about, .ind also presents the

■

«^,

\- ., :

., i

Salicylic Acid in Precrystalline state, shuwini^ numerous
petrublasts with nuclei, linlargement, '>io.

peculiarity of being .able to reproduce ilsell in lliii'C
ways — by division, genirnation, and endugeny.

" I. By division. II we take, in special condi-
tions, a crystal of recent formation, we shall see it
separate into two individuals which draw apart with a
rotatory movement.

" 2. By gemmation. The phenomenon takes jikice
ill the following manner : the petroblasts develop, reach
the surface of the crystal, continue to deyelo[), and are
detached, causing waves around the crystal.

" 3. By endogeny, the most originjil case. A little
crystal forms inside the mother crystal, comes to the
surface and issues from it with a double movement oi
[jrogression and rotation.

" Life in crystals can be explained by the struggle
for existence, which is ardent even here. In f.ict, if
during their growth two crystals come into contact,
the weaker will completely disappear, absorbed by the
stronger. . . . The crystal seems actually to be ;i
living being, and, as we have said, it should have its
special pathology. This is really the case, according
to Von Schron, who has discovered fifteen kinds of
disease in crystals, some of which are hereditary — cases
of bifurcation, torsion, and erosion, which are confirina-

1 84

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

tory of the new theory. When its vital cycle has been
complete, the crystal then becomes old and is i'ossilised.
It is then inert."

What is the origin of the little globules whence,
as has been stated above, all crystals arise -^ Have they
germs or seeds of some kind ? \'on Schrcin thinks not.
He regards the inception of the crystal as real
spontaneous generation. Al. di Brazza, however,
criticises this attitude. He asks :

" Why can we not ascribe to the molecule, this in-
finitely small constituent part of things, the primary
generative faculties and substitute for the formula; of
Redi and \"ircho\v* a new one : Oiniic viviitn ex mulccida
[all life from the molecule]? "

This hypothesis the writers submitted to \'on Schion,
who reallirms his belief that the crystal has absolutely
no pre-existing nucleus, molecular or other, in the solu-
tion in which it arises.!

* Omnc cclhda c cclluld.

t Professor Von Schriin remarked in his earlier papers that in
the preparation and development of bacilli four products were
evolved. They were — i., a colourless liquid which forms the envelope
about the spore-forming bacillus; ii., gas; lii., irregular masses of
albumen; iv., crystals.

(Dbituary.

DR. ISAAC ROBERTS. F.R..S.

It is with exceeding regret that wc have to record the sudden
death on Sunday, July 17, of Isaac Roberts, U.Sc. (Dublin),
F.R.S., F.R.A.S. There is no need to tell the readers of
" Knowledge " of the contributions which Dr. Roberts made
to the science of astronomy by his photographs of stars,
clusters, nebulae, and comets. Many of these he published in
its pages, and his last contribution— three beautitul presenta-
tions of Comet Borelly (c 1903)— in the October number of
last year, must be fresh in the minds of all. Since iSyo he
devoted himself almost entirely to astronomy at his residence,
Starfield, Crowborough, where he built an observatory,
equipped with a 20-inch reflector and a 5-inch Cooke refractor.
In earlier years he had also made a study of geology, and was
elected a Fellow of the Geological Society in 1S70. In 1SS2
he was elected a Fellow of the Royal Astronomical Society ;
he served on its Council for some years, and was awarded its
gold medal in 1895 for his astronomical researches. In 1S90
he was elected a h'ellow of the Royal Society, and in 1892 the
University of Dublin conferred on him the hon. degree of
Doctor of Science. In October, igoi, he married Mdlle.
Dorothea Khnnpke, D.-es-Sc, who had previously been head of
the Bureau for measuring the plates of the International Cata-
logue in llu: National Uljservatory at Paris. In 1893 and 1899
he publislicd two volumes of photographs of star-clusters and
nebuhe, photographs which, if his work is continued, will
afford ere long evidence of the nature of the changes which
are going on in the stellar universe. Dr. Roberts was born
in 1829.

CAPTAIN WILLIAM NOBLE. F.R.A.S.

English astronomy h.is sutfcred a very grievous loss in the
death of Captain William \ol)lc, of Forest Lodge, Maresfield,
L'ckfield, Surrey. He was l)orn in 1828, and for some years
was a member of the Rifle Brigade, .ind after his retirement
from the service he took an active interest in the politics and
business of his county, l)eing a Justice of the Peace for many
years before his death. He took a great interest in many
scientific subjects, but liis chief pursuit was astronomy, and he
was elected a l'"cllovv of the Royal Astronomical Society on
June 8, 1855, and served on its Council with but short inter-

missions from 1867 until 1902. He was an original member of
the British Astronomical Association, was its first President,
serving from 1890 to 1892, and contributed largely to its success.
He conmiunicated many papers to the " Monthly Notices" of
the Royal Astronomical Society, to the "Journal" of the
British Astronomical Association, to the " Observatory," to
" Knowledge," and to the " English Mechanic." To thelast
periodical he contributed for many years a fortnightly letter,
under the signature of a " Fellow of the Royal Astronomical
Society." He had also the author of " Half-Hours with a
3-inch Telescope," a book of great practical value and aid to
amateurs beginning a study of the Moon and planets. He
was himself a good observer, and his drawings ot Jupiter and
Mars and of portions of the Moon are both truthful and
accurate. He was a most engaging personality. It was not
only that he took an interest m astronomy and the work of
astronomers, but he manifested his interest in a breezy and
genial fashion. He had always ready to help by word or
letters the novice in the science that he himself loved. His
death took place on Saturday, July 9, 1904.

PROFESSOR THEODOR BREDICHIN.

Professor Theodor Bredichin died on May 14, 1904, after
a short illness. Russia has lost in him her most eminent astron-
omer and the one who has had most influence on the develop-
ment of astronomy, both as Professor and as Director, success-
ively, of the two largest Russian observatories — Moscow and
Pulkowo. He was born on December 8, 1830, in Nicolaieff,
and was educated first at the Richelieu Lyceum in Odessa,
and then in the University of Moscow. He was elected Pro-
fessor of Astronomy at the University in 1857, and in 1873
was made Director of its observatory. Here he initiated
observations of stellar spectra, of the places of stars, and the
determination of gravity through observations of pendulums.
But bis great work was his research on the forms of comets
with which was connected his theory of meteors. In i8go he
succeeded O. Struve as Director of the great Pulkowo Obser-
vatory, and here he remained until 1894, when be resigned
his Directorate and retired to Petersburg to pursue his comet-
ary investigations. He was elected a foreign Associate of the
Royal Astronomical Society in 1884.

At the Royal Society's conversazione was exhibited
a little instrument devised by the Hon. K. J. Strutt
and called a radium electroscope, in which the de-
parture of negative ions from a speck of radium en-
closed in a scaled vacuum tube perpetually charges the
leaves of an electroscope also inside the sealed tube.
The action is probably not perpetual, but so long as
the radium lasts, say 30,000 years, the tiny leaves of
the electroscope will go on opening and shutting so
many times a minute, like a clock or a perpetiud motor.
But this spectacular form of motion is not the limit ol
the radium electroscope's potential activities. Mr.
Harrison Glew has devised an arrangement by which
the periodical discharges of the electroscope, when the
lea\ es touch the side of the sealed glass tube (in which
;i w ire connects two inner coatings of zinc foil to earth),
rings a bell or prints a record of every contact of the
lea\es. Each discharge from the outside terminal of
zinc foil and wire, when the leaf strikes the inner foil,
is sullicient to ;ict on a " coherer " similar to that which
is used in wireless telegraphy. The "coherer," as in
a wireless telegraphic system, is put in a bell circuit,
and each time it is acted on, as it might lie acted on by
a train of Hertzian waves, it rings :i bell. In Mr.
'Glew's experiments, with a three milligrammes speck
of radium, the bell was rung every se\enty seconds.
Thus we might devise a perpetual " minute bell."

August, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

185

The Dolls of the Tombs

The Bervi Ha.sa.n Excava.tions.

Bv the kindness of Mr. John Garstang', director of the
Beni Hasan I£xca\ ations, we are able to reproduce
some photog;raphs of the extraordinarily inlerestint;
models and the fascinating- dolls which Iiave been found
by him in the excavated tombs of Beni Hasan. Our
thanks arc also due to the Council of the .Vnthropo-
logical Institute, in whose journal, J\Iii>i, ^^av, 1903
and July, 1904, the photographs have already appeared.
These models, placed in their rocky tombs 4,000 years
ago, were recently exhibited at the -Society of .\nti-
ciuaries' Rooms, Burlington House, and proved witliout
doubt the most attractive archaeological exhibition of the
year. Some of the models have been shown in London
before, and Princess Henry of Battcnberg was an
interested visitor, not at Burlington House alone, but at
the excavations themselves in Egypt. The attraction
of the dolls is of a double kind. It lies not only in the
knowledge that they are the handiwork of 4,000 years

string Dolls. Tomb 420.

ago, or that they represent the life of those times as
well as the probable superstition that the presence of
such dolls in tombs ensured for the human body buried
there the company, assistance, and service of slaves,
.soldiers, and equipment in the Paradise where the soul
had gone ; but it is to be found also in the extraordinary
vividness of the df)lls themselves. They are sometimes
rudely carved, but they are always lifelike. There arc
dolls in granaries and dolls in war-galleys — wonderful
dolls these, with a world of expression in their glaring
eyes, though the eyes are only two dashes and a dot —
and a w-ondcrful vigour in the way their wooden arms
strain at the sweeps. You can almost hear the yell of
the steersman and the crack of his whip. Then there
are dolls baking, kneading, butchering ; and a wooden
bullock with meek legs bound together is ready
decorated for the .sacrifice. The wooden priests stand
near with wooden gestures of uplifted piety. In one
galley the dolls are pla3'ing chess ! Then there are
dolls of historic interest ; the dolls that point to a
Libyan irruption and a renaissance of new ideals in the
art of dolls ; and a beautiful wooden portrait doll, with
an archaic smile on his well-cut lips and determination
writ plainly on his jaws and fist. Lastly, there are the
real dolls of that forgotten day, dolls that were made of
string and had curly locks of threaded beads — such

were the dolls that little Xoith-IIetep or .\ycsha played
with 4,000 years ago.

Of the exc:ivations, Mr. (iarslang writes : — " It was
early in December, 1902, that excavations commenced
in the vicinitv of Beni Hasan. The site is on the east
bank of the Nile, where the river approaches somewhat
closely to the limestone cliffs lh:it bound the \allev,
some fourteen miles southward fiimi Mini.i, a great

i;.iat of Twenty Oars. Tomb 116.

town of Middle l^gypt. The site has long been famous
for its long gallery' of Middle Empire tombs, which are
hewn in the living rock, well up the slope. These are
decorated in their interior with scenes, painted with
realism upon the dressed surface of the walls, which
are the more interesting in (hat they represent, in many
cases, incidents of daily life in the home and in ihe
fields, as well as the rites perl.-iining to the dead, in the
age to which they belong, more than 2, coo years n.c.
Historically they belong to the feudal period of Ivgypt,
when the Government was in the hands of powi-iful
chieftains — hereditary owners of the soil, and they
bridge over the intervening years during \\lii<li the
monarchy slowly regained its authority, and was finally
re-established by Amenemhat III.

These great rock-hewn chambers, for 1I10 most jiart,
indicate the burial places of these feudal lords, whose
great sarcophagi were placed in small recesses at the
foot of deep square shafts within them. It might have
been suspected that the court officials of these great
chieftains, who kept up regal pomp, would seek burial
in the same vicinity ; and that the tf)mb furniture and
burial deposits placed with them might illustrate more
fullv the civilisation and culture of the age : such was,

The Making of Beer. Tomb 116.

indeed, the quest of this expedition. The necropolis
w-as discovered ranging along the face of the cliff, just
below the famous gallery ; and 887 tombs were found
and excavated during the two years' work. The pre-
sence of these was already indicated, indeed, by the
numerous open mouths of shafts sunk in the lime-
stone.

The first tomb discovered and entered gave an indica-

i86

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

lion, '{'he shaft harl been found filled 1)\' dt-siL;ri with
1,iil;c masses of roek and the door of the ihanilier was
closed V, iih roiit;h-(h'essed stones built up like a door.
On i( inoxing' these the interior showed the tomb of
a eourlier n.amed Antcf, imdisturbed and preserved in
its entiret}' as it had been left by the anrient Egyptians
at his funeral, 4,000 years before. The wooden
sarcophagus, with its lines of religious formula? and
text painted in hieroglyphic cliaracter upon it, lay
within, head to the north, and the painted " eyes of
Osiris " towards the 0.1st. I'pon it, and by its side.

Boat with Armed Man.

wi-ri' little wdoflen models of rixer and sailing lioats, a
gr.inar\ , a grouii ol persons baking, a man brewing,
another leading an o\, a girl carrying ;i brace of birds
in hri- h.ind and a basket on her head. The o.arsmen
still <linging to their oars, through all the lapse of
ye.ars, and the paint was fresh upon the \\(io(len figures.
It was a wonderful sight ; one which rewards a life-
time. Within the sarcophagus were the bones of
.Ante!, wrapped around with a linen cloth, which was
still preser\ed, while the body had decayed. His
pillow, a wooden one, was bv his head, and a pair of
sandals at his feet.

This first tomb entered proxed characteristic of the
w hole number, and the result is a wealth of information
as to the life and ritual of the Egypt of that distant
day.

ASTRONOMICAL.

A Possible Varia-tion of the Solar
RaLdiation.

Tm-: .Islrn/^hysirtil Jniiniti! for June opens with a paper by
Professor S. F. Langley, in which he shows cause for conclud-
ing that there was probably a fall in the solar radiation at the
end of March, 1903. The determination of any such variation
in the solar constant is one of extreme difiiculty owing to the
great and varying effects of the absorption exercised by our
.itmosphere, and Professor Langley puts his results forward
with all due caution. But the introduction of automatic
methods for registering the observations of the bolometer, and
improvements in the instrument itself, so that the zero of the
galvanometer remains almost unchanged for weeks together,
justify the attempt to ascertain if any such variation can be
detected. The chief difficulty lies in the calcid.ition of the
total absorption exercised by our atmosphere so that the
radiation recorded at the observing station may be corrected

so as to exhibit the radiation as it would be recorded were the
atmosphere removed. The only method at present available
is by the comparison of observations made with the sun at
different altitudes, and acting through different thicknesses of
air. The measurement and reduction of a series of from five
to ten holographs of a single day involves so much labour that
a single computation of the solar constant takes about a week.
The effects due to the atmospheric absorption having been
allowed for, a series of observations made at the Smithsonian
Astropbysical Observatory, from October, 1902, to March,
1904, appears to show that the solar radiation itself fell off by
ai)Out 10 per cent., the change l:>eginning late in March, 1903.
Such a change should be followed by a decrease of tempera-
ture on the earth less than 7-5" C, and on comparing the
observed temperatures at .S9 stations in the North Temperate
/one, an average decrease of temperature of over 2° C. was
actually found to be shown; stations far from the retarding
influence of the oceans showing the greatest variation. The
mean temperature curve of the S9 stations shows a striking
correspondence with the curve of the solar constant during
the fir=t 8 months of 1903, but rises in the last 4 months.
This ri.se may be due to an increase in the transparency of the
earth's atmosphere, the Smithsonian observations indicating
that there was a great falling off in such transparency from
I'ebruary to August, 1903, but a recovery later, though the
in iximum value recorded in 1901-2 was not fully attained.

-)t * *

The Electric Equilibrium of the Sun.

An import. nit paper by Professor Svante Arrlieuius was
communicated to the Royal Society on June 2 by Sir William
Huggins. Professor Arrhenius had previously pointed out
that several electric and magnetic phenomena might be con-
nected with the pressure of radiation. The gases in the solar
atmosphere are practically ionised by the ultra-violet radia-
tion ; the negative ions condensing vapours more easily than
positive ions. A large majority of the droplets formed by con-
densation in the sun's atmosphere arc thus negatively charged
and driven away, charging with negative electricity the atmo-
spheres of celestial bodies, c.i,'., the earth, which they meet.
Calculating the speed with which these particles will move
through space, Arrhenius finds that on the average they
would reach the earth in aliout 46 hours. Now Ellis and
INIauuder have shown that the magnetic storms commence
26 hours in the mean after the sun spots which probably
cause them reach the central meridian of the sun. Ricco
found that the height of the storm is attained on the average
about 45'5 hours after the transit of the spot : a result prac-
tically coinciding with that of Ellis and Maunder, and with
the speed deduced by Arrhenius for these negatively electri-
fied particles.

But a difficulty arises here, for the emission of these par-
ticles from the sun should result in its soon assuming so
great an electric charge of positive sign as to hold back the
negative particles. But if these drops should agglomerate
the potential increases, and larger masses are formed which
can part slowly with their negative charge in the form of
electrons traversing space with a velocity much less than that
of light. Such electrons would, in general, not pass by many
suns without being caught by them. In this way. Professor
Arrhenius suggests that the supply of negative electricity to
the suns is proportional to their deficiency in it. This balance
supposes that the chief forces driving the particles away from
tlie sun are, like the pressure of radiation, not electric ; but
for the negative electrons caught by the sun, forces other than
electric are relatively insignificant.

* * *

Mr. Yendell's Observations of the Colovir
of Certairv Variable Stars.

In the Astronomical Jounui} for June 20, 1904, Mr. Paul
S. ^'endell gives an extension of Professor Chandler's examina-
tion of the colours of the variable stars {A. J., \TII., 137) to
the more recently discovered variables. The observations
were made with a screen of a full blue colour, formed into a
double eye-glass, so that it could be used either with the naked
eye or with the binocular, and an examination of the spectrum
of the light transmitted by this glass showed a large absorp-
tion throughout the whole of the red and yellow. The obser-
vations were carried on more or less continuously from 1893

August, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

until icx>i, and the cases of 53 stars are discussed. Tlicse 55
stars are divided into three classes accordins; to their types of
variation. There .are ei,t;ht sliort '• period stars of ll\c
t; .\i]ail;e .and ,.i Lyra* types: seven of types wliich m.iy he
called intermediate with periods of from 4(1 to 163 days ; .md
38 stars which are distinctly of the louf^-period type. In the
first class, where the stars h.ave .a short-period variability, there
does not seem to be any sussestiou of a relation between
colour .and length of period. In the second class, or '• inter-
mediate " stars, there is evident a marked progression in the
lengths of their periods, corresponding to that in their
observed colours. In the third class, consisting of 5S long
period stars, the correspondence between depth of colour and
length of period is so marked as to point strongly to some
real connection between the two. confirming Chandler's dic-
tum that •' The redder the tint, the longer the period." The
variation .also seems to become increasingly irregular.

* * *

The Spectroscopic Binary, ,3 Aurigae.

Not quite a ye.ar ago. Mr. (',. A. Tikhot'f. from a discussion
of spectrograms of .-( .Auriga' taken at the Fulkowa ( )bser\a-
tory, concluded that the star is not merely double but (pi.-ul-
n;ple, being composed of two groups of bodies, each of whicli
consists of a star with strong lines and a second star willi
weak lines. The revolution of the two groups takes place in
slightly less than four days, but of the stars in each group in
one-fifth of this time. This inference was based on the com-
plex appearance occasionally presented by the H^line; and
caused Professor Vogel to set on foot a new seri(;s of observa-
tions of the star. These have not led him to support Mr.
TikhofTs views. By a very slight alteration of the adopted
period he was able to bring the 85 observations at his disposal
ver>' satisfactorily on a single curve ; and he concludes that
there is no sufficient reason to accept the quadruple structure
of the system. With a circular orbit and a period of ,5'<)59<)
days, and a rehative velocity of 222km., the mass of the system

comes out .as 4-5 sin ^ / that of the sun, and the distance of the
two bodies apart as 11 sin i = 12.000.000 km. The radial
velocity of the system is found by Vogel to be — 2t + i km.
agreeing well with those found by Deslandres and Tiklioff.

* » *

The Visibility of Lines a-nd Wires.

Mr. Lowell is following up liis earlier experiments as to
the extreme limits of visibility of lines and wires, and in
Bulletin 10 of the Flagstaff Observatory, he gives the results
obtained by two of his assistants. These found it possible to
glimpse or suspect a line or wire when its angular width was
only o"'8 of arc. No marked difference was found between
the limit for a blue line ruled on white paper, and that for a
wire seen against the sky.

* ■)(■ *

Radial Velocities of the Pleiades.

The Pleiades in general do not give spectra favourable for
determinations of radial velocities; they lack the metallic lines
seen in Sirian and solar stars, and the lines of helium are
usually weak and diffuse. Mr. Walter S. .Adams has been able
to deal with six stars of the group with some success; the
speeds deduced in kilometres per second being as follows : —
Merope + 6, Atlas + 13, Electra + 14, .Alcyone + 15,
Taygeta + 3, whilst Maia was found to v.ary in velocity.
Merope was ob.served with most difficulty, Maia with least ;
the first four stars showing spectra like those of nebulous
stars, whilst Taygeta and M.ii.i should possibly be regarded
as not physically connected with the nebulosity.

An Expedition for Solar Research.

Professor G. E. Hale is conducting an expedition to Mount
Wilson (58S6 feet), near Pas.adena, California, for the purpose
of making special investigations of the Sun. The chief instru-
ment will be the Snow horizont.il telescope recently constructed
at the Verkes Observatory. This consi.sts of a 30-inch C( clost.it,
with a 24-inch subsidiary mirror by which the light can be
deflected on one of two concave mirrors also of 24 inches
diameter. One of these has a focal length of 60 feet, the other
of 145 feet. The latter giving a i6-inch solar image will be
used in conjunction with a spectroheliograph of 7 inches aper-

ture .and 30 feet focal length. Throe foc.il slits will be used
together, so that three different parts of the sjiectrum mav l»'
photographed simultaneously. Thedo-foot mirror is to be also
used in connection with .i spectroheliograph, but a special
attempt will be maile to photograiih with it sonu' of the
brighter stars, using a stellar spectrogr.iph provided with a
large concave grating .and mounted in .1 constaul tempcr.iture
Laboratory.

* * X-

Eclipse Problems.

In the Pof'uUif Science Monthly for Jime, 1004, Professor W.
W. Campbell discusses the more important points of eclipse
problems. He first considers the (piestion of intramercm iai
planets. The experience of icjoi w.is almost but not (|uite
conclusive .against their existence ; if simil.ar successful pholo
graphs were taken in L.ibr.idor, Spain, Tunis, and Egypt in
1905 the (juestion would be settled one way or other. The re-
versing layer comes next. Additional work with more power-
ful instruments in perfect adjustment is reepiired ; and
esp<'cially photographs taken on continuously moving pl.iles
are needed, since exposures of two or four seconds iutegr;ite
the ch.anges which are going on. The chief problem is the
corona, since we do not yet know wliellier the m.aterial of the
stre.imers is moving outward, inw.u'd, or in both directions, or
in neither. It is essenfi.al that idcuticd instruments of long
focus be employed in at least three widely separated stations to
photograph the corona with .1 connnou scheme of ex|)osures.
Professor Campbell regards this (|uestion of coron.il movement
as the most import.mt of the coming eclipse. ( )ther problems
are the sources of light and heat for th(; outer corona, calling
for thcrmogr.iphic and polarigraphic observatiiuis ; the bright-
line spectrum of the inner corona in 1(105, ^f sun-spot maxi-
mum, comparing the thickness and uniformity of this siralum
with the results obtained ,it the recent eclipses at minimum ;
the .accurate determination of the wave length of the truly
coronal lines so that a serious effort may be made to represent
them by a simple couunon law, ;is with hydrogen and helium.
Professor C.-inipbell concludes with insisting on the need lor
insuring against person.al failures by at once making the fullest
possible preparation. I'''ailurcs in the p.ast have been Largely
due either to attempting too large a programme for the time
of totality, or more usually to want of adequate experience of
the instruments or methods employed.

ORNITHOLOGICAL.

Bv W. P. PvcRAFT, A.L.S., F.Z.S., M.B.O.LL, &.c.

Killdeer Plover in Aberdeenshire.

Ki;ai)i;rs of this column will prob.ibly be interested in the
fact that I have just discovered an undoubtedly Piritish-killed
example of the Killdeer Plover [.litiialitis. vmifcra) in the Uni-
versity Museum of Aberdeen, though for tiiirty-seveu ye.irs it
has passed for the common ringed Plover (./■,'. hi(ilicuta). The
label on this specimen runs as follows : " Cluiriulrins hinticuta,
Ringed Dotterel, sliot .it Peterhead by Andrew Mnrr.iy,
jun.. Esq., 1867."

From this Libel, which is yellow with .age, there can be no
doubt but that this bird was presented by the donor simply
as a common ringed dotterel. To .allay all doubt, Professor
J. Arthur Thomson, in whose care this bird now rests, has
kindly interviewed Mr. Murray for me, and he distinctly
recollects the circumstance in connection with this incident.

The Killdeer Plover is .admitted into the British list by Mr.
Howard Saunders on a single example shot at Tresco. Scilly
I.slands, and described in the Zooloi;iHt for 1SS5, p. r 12.

* * *

Yellow-legged Herring Gull at Dover.

At the Last meeting of the Ornithologists' Club, held June 15,
the I Ion. N. Charles Rothschild recorded that he had observed
in DoverH.arbour, on April 18 Last, a bird which he considered to
have been an example of the \'el low -legged Herring Cidl {l.iinis
cachinnaus). The bird in question was flying in company with

1 88

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

several of the common Herring Gull (L. «):, md passed

unusually close.

The bird was noticed to have orange legs, not only by his
brother, the Hon. Walter Rothschild, but also bv the Hon.

F. R. Henlev.

» * *

Longevity of Eagle Owl.

Mr. E. G. B. Meade-Waldo has just forwarded to the
Natural Historj- Museum a female Eagle Owl (Dtdio igitavus),
which had lived seventy-two years in confinement, having
been brought from Norway in 1829: and during the last fifty
3'ears had reared no less than ninety 3'oung.

The mate of this bird is now fifty years old, and still vigorous.

Although the Eagle Owl is reputed to live to a great age,
there are surprisingly few similar instances recorded where the
age has been definitely ascertained. A golden eagle which died
at Vienna in 1719 was known to have been captured T04 years
previously ; and a falcon, of what species is not recorded, is
said to have attained an age of 162 years. A white-headed
vulture taken in 1705 died in the Zoological Gardens at Vienna
in 1S24, thus living 118 years in captivity.

Herring Gull Laying in Confinement.

I have recently obtained circumstantial evidence of the fact
that a Herring Gull {Lams Ar^entatus) has, after twenty-two
years in captivity, commenced egg-laying. Two eggs were
laid by this bird during the present spring, at intervals of a
week. Both were quite normal in size and colour, and. after
laying the second egg, the bird commenced to sit. but the eggs,
of course, were infertile. Wild Herring Gulls frequently
approached her, but of these, strangely enough, she took no
heed.

* * *

Breeding of Crested Screamer in
Confinement.

A pair of Crested Screamers iChauna chavavia) have just
successfully hatched out three nestlings in the Gardens of the
Zoological Society. Careful observations kept during the
period of incubation .show that the male takes a full share of
the brooding, which lasts three weeks. The young are said to
resemble goslings, but not very closely. They are }'ellow in
colour, and have no stripes. They are described in the Field
for July 9 as having no down, but being clothed in feathers
which are miniature copies of those of the Khea. This descrip-
tion is somewhat remarkable, and demands further considera-
tion.

* * *

Allen's Gallinule at Sea.

.\x\ example of Allen's Gallinule (Porphyriola AUeni) has just
been sent to the London Zoological Gardens. It was taken
at sea, 140 miles from the nearest land — the west coast of
Africa. \ similar instance occurred in 1S79, when a specimen
was taken on board a ship off the coast of Sierra Leone.

ZOOLOGICAL.

Arn\adillos in North America.

With the exception of one or two species, ranging into Texas
and the adjacent States, armadillos, both recent and fossil,
have hitherto been supposed to be confined to South and
Central America, inclusive of Mexico. The discovery is, how-
ever, announced of the skeletons of extinct members of the
group in the Lower Tcrtiarj', or Eocene, formations of the
United States. In place of the bony armour characteristic
of the existing and later Tertiary members of the group, these
primitive armadillos appear to have had their backs protected
merely by a shield of hard leathery skin. '1 he discovery must
profoundly modify current views as to the origin of the
South .American fauna, indicating apparently that armadillos,
at any rate, wereinmiigrauts into the southern half of the New
World from the North.

An Insect Pest.

One of the most terrible of insect pests appears to bs the
minute black fly of the Mississippi Valley, commonly known as
the buffalo gnat, from a fancied resemblance in outline to the
buffalo, or bison. The buffalo-gnat chiefly attacks the larger
kinds of live stock, although it will occasionally bite, and even
kill, human beings. In the year iS74it is stated that in a
single county in Tennessee these insects killed stock to the
value of /loo.ooo; while within a single week one parish in
Louisiana lost 3,200 head of live stock. Horses and mules,
during such visitations, are killed while working, or before they
can be got under cover when grazing ; while in some of the
cities on the Mississippi the running of tramcars has been ren-
dered impossible.

* * *

G\ills and Fish.

Confirmation of the view expressed in our last issue as to
the serious extent of the damage caused to our sea-fisheries
bv gulls is afforded by a note in the Field of July 11, from
^ir. J. A. Harvie-Brown, a well-known field naturalist.
-According to this gentleman, there can be no doubt that cer-
tain species of gulls, if not indeed all, are fir too numerou?,
not only on account of the fish they destroy, but also owing to
the destruction they inflict on the eggs and young of other birds.
Mr. Harvie-Brown goes, however, further than this, and con-
siders that much of the bird protection in this country is
downright harmful.

* * *

A Rare Rodent.

Everything comes to him who waits. -\s noticed in our
summary of papers read. Dr. E. .A. Goeldi has recently com-
manicated to the Zoological Society a notice of certain
rodents living in the Museum at Para, Brazil. The species to
which these rodents belong (Diiioinvs hranicki) has been hither-
to known only by a single specimen which was found early one
morning about the year 1S73 wandering in the courtyard of a
house in Lima, Peru. Although it was considered by its
describer to indicate a family and genus whoss nearest relative
is the Paca (Calogcnys piica), the suggestion has been made that
it was a hybrid between that animal and some other large
rodent. The specimens now living at Para suffice to dispel
this theory ; and when Dr. Goeldi's description is published
we shall be able to appreciate the true affinities of this re-
markable and interesting creature.

* * «

The Orkney Vole.

Unusual interest attaches to the discovery by Mr. J. G.
Millais in the Orknej'S of an entirely new species of short-
tailed field-mouse, or vole, which is described in the /^(wlogisl
for July under the name of Mici-olus oirndeiisis. Having no
affinity with the red- backed, or bank, vole {Evotoiiiys glnriolm),
the Orkney species comes nearer to the common field-vole
{Micnitns aqrestis). from which it differs not only in proportions
and colour, but likewise in the structure of its cheek-teeth.
It is, therefore, nothing in the way of a sub-species, but a per-
fectly distinct species, which does not appear to present a
near relationship with any other known member of the group.
That such a totally distinct type should turn up in the Orkneys
is certainly most surprising, and it suggests a number of pro-
blems in the geographical distribution of animals. Mr. Millais
is to be heartily congratulated on having been the means of
making known such an important and interesting addition to
the British mammalian fauna.

■i^ -^ --^

Papers R^ead.

At the final meeting for the session 1903-4 of the Zoologica
Society of London a large number of exhibits were made and
papers taken. Among the exhibits, reference may be made to
a series of hybrid pheasants killed in the coverts at Woburn
Abbey belonging to the Duke of Bedford ; and likewise to a
skull of the Cape crowned crane, showing bony processes sug-
gestive of the horns of mammals. Living specimc ;is of hairless
rats and mice were also shown. The papers included one by
Colonel J. M. Fawcett on certain butterflies from the North-
West Himalaya and elsewhere, and a second, by Mr. .^. G.
Butler, on seasonal changes in butterflies. Captain R.
Crawshay contributed notes on the prey of the lion, directing

August, 1904

KNOWLEDGE & SCIENTIFIC NEWS.

i8g

special attention to a number of porcupine quills found buried
in the fore-paws of one of these animals. Mr. F. E. Beddard
read papers on certain features in the anatomy of three groups
of reptiles, namely skinks, sea-snakes, and the Australian
skinks of the genus '/"i/ii/Hii. Next came the communication
by Ur, Goeldi on the South .\mcrican rodent Diiioiiiys hianicl-i
to which special reference is made in an earlier paragraph of
these " Notes.'" Dr. C. Satunin described the black wild cat
of Transcaucasia as a distinct species ; while Mr. Lydekker
contributed notes on a new race of buffalo from Hast Central
Africa, and on a new species of tufted deer (Elaplivdus ichaui^-
tnsis) from Ichang, Central China. Finally, Dr. A. S. Wood-
ward read a paper on two skulls of primeval salamanders, or
lab)-rinthodonts, from strata of Triassic age, the one from
Staffordshire and the other from Spitsbergen. At the last
meeting for the session of the Geological Society of London,
Mr. \V. F. Gwinnell described the vertebral column of a small
plesiosaur from the Rhictic strata of W'estbury-on- Severn,
Shropshire. Hitherto the plesiosaurian vertebra; obtained
from this horizon have consisted only of isolated vertebr;c.
At the final meeting for the session of the Linnean Society
held on June 16, Dr. W. Kidd read a paper on variations in the
arrangement of the hair on the neck of the horse, in which it
was sought to test the validity of the theory that certain pecu-
liarities in hair — arrangement among them — are generally
due to mechanical causes. Mr. J. Cash contributed a paper
on British freshwater rhizopods.

« * «

The Poison of Vipers.

For some time it has been known that the serum prepared
from cobra-poison and known as Calmette's antivenin is to
a great extent effectual against the results of the bite of the
snake itself. Experiments have recently been undertaken by
Dr. Rogers, of the Indian Medical Service, with a view of
ascertaining whether a similar serum has equally good effects
against the results of the venom of the Indian sea-snakes and
other members of the colubrine group whose bite is poisonous.
The results of these experiments have been published in a
recent issue of the " Philosophical Transactions," and serve to
show that the poison of all these snakes has the same effect,
namely, paralysis of the lungs. Accordingly, there is every
probability that such poisonings may be neutralised by a
serum Uke Calmette's antivenin, although this must be of
much greater strength in order to be effective. On the other
hand, it has been found by Dr. Rogers that the poison of
snakes of the viperine group, such as the true viper, pit-vipers,
and rattlesnakes, belongs to an altogether different category,
causing paralysis of the heart. To fight this effectually it
would seem necessary to prepare from vipers' venom a serum
analogous to Calmette's antivenin ; and until this be dis-
covered, only empirical methods of counteracting the effects
of the poison can be emploved.

* ' * »

The Supply of Ivory.

During a recent visit to the London Docks, Her Majesty
the Queen was informed that the stock of ivory then shown
represented, on an average, the annual slaughter of some
20,000 .\frican elephants. This statement has been contra-
dicted in two letters in the daily papers. In one of these
Messrs. Hale, of 10, Fenchurch Avenue, state that at least
85 per cent, of the supply is " dead ivory, " mainly obtained
from hoarded stores of the African native chiefs, who are
shrewd enough to put their commodities on themarket only in
driblets. The most interesting part of the letter is, however,
the statement that the great bulk of this hoarded ivory is
obtained from " elephant cemeteries " — spots met with here and
there in the jungle where elephants have resorted for cen-
turies to die. Much of the ivory that comes to the market
may, therefore, according to this letter, be several hundred
years old. The marvel is why it is not devoured in the jungle
by porcupines, as certainly happens with tusks of the Indian
elephant which are left in the jungle. The letter adds that
very little ivory is now obtained by hunters.

* * *

Popular Economic Zoology.

The following is culled froni the •' Woman's Column " in a
recent issue of a local paper : " There are two divisions of
pearls, the Oriental, by far the most valuable, and the baroque

The latter are embedded in shells, and have to be cut out — a
process at once diflicnlt and delicate, needing to be performed
hy very practised workers. The Oiienlal, of course, are
found in fish. The pearl, although one of the most beautiful
of jewels, and a particularly dainty gem, has a curious origin.
It is formed by the saliva of fish, and it is supposed lliat a
grain of sand, perhaps, or some otlier ctjually initating foreign
matter, has caused the fish discomfort, and it has covered the
sore with saliva, pursuing the process continually until a
pearl of considerable size becomes formed. This is proved
by the fact that when a pearl is cut in half .always a small
speck is found in the centre." .\nd this in an age when we
have technical education and science lectures all over the
country, to say nothing of special memoirs on the origin of
pearls in various scientific journals !
* ♦ »

Striped Hawkmoth in En{?land.

In his '■ British Moths," published in ift;.), the late ICdw.ird
Newman, in describing the species known as the striped
hawkmoth (DiU-philci livuniica), stated that most of Ihe speci-
mens alleged to be British were really of Continental origin,
but that there were a few undoubted British examples of this
beautiful moth. According to the Entom(ilot;i\t for June, the
present year will be notable for the number of specimens of
this species taken in this country, no less than eiglit being
recorded in that issue. The localities where these captures
were made are Carlisle, Yelverton (near Plymouth), Worm-
well (near Dorchester), Marsemoor (near Gloucester), Bourne-
mouth (where another specimen had been taken earlier in the
year), Brockenhnrst, and the Isle of Wight (2).
» » »

A Link between Birds aLnd Reptiles.

It is a well known fact that in certain groups of birds —
notably the petrels and albatrosses — the horny sheath of both
the upper and lower half of the beak is composed of several
distinct pieces. In a communication to a Swedish Zoological
journal (Arkiv fur Zoologi, vol. i., p. 479), Dr. E. Lonnberg
identifies these elements with certain scales to be found on
the head and lower jaw of lizards and other reptiles. If these
conclusions be well founded, we have another link in the
chain connecting birds with reptiles.

BotaLrvicQLl Notes.

By S. A. SK.A.N.

The genus Begonia, in some of its numerous repre-
sentatives, is met with nearly everywhere where plants
are cultivated, and though differing very markedly in
their vegetative characters, all its species are generally
easily recognised by their flowers. When the order
Begoniacea; was elaborated for Bentliam and Hooker's
Genera Tlantarum, the number of species of Begonia
known was about three himdred and thirty, natives of
the warmer parts of Asia, Africa, and America. One
of the most recent additions to the genus is dealt with
by Dr. Trelease in the Fifkeiilh Annual Report of the
Missouri Botanical Garden. The new species, appro-
priately named by Dr. Rose Begonia unifolia, is re-
markable in possessing only one leaf. It belongs to
the tuberous-rooted group, and its scape, bearing a
few, rather small, nearly white flowers, arises from the
sintis of the single rounded leaf. The plant is peculiar
in its habitat, for it was found growing on rocks, with
its roots penetrating into crevices ; and the large leaf
is closely adpressed to the surface of the rock, serving
an important function in protecting the lower portions
(jf the plant. It is a very distinct species, having only
one close ally, B. monopliylla, a little known plant from
New Spain.

I go

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

1 he United States Department of Agriculture lias re-
cently issued a useful bulletin, by Dr. G. T. Moore and
Mr. K. F. Kellerman, on " A Method of Destroying or
Preventing the Growth of .-Mgae and certain Pathogenic
H.icteria in Water Supplies." The presence of .^Igae
in water frequently causes trouble, and many of the
methods recommended for getting rid of it are im-
practicable, inasmuch as their adoption would spoil the
water. According to the writers mentioned above, " it
has been found that copper sulphate, in a dilution so
great as to be colourless, tasteless, and harmless to
man, is sufficiently toxic to the Alga: to destroy them
or prevent their appearance. A solution of one part
of the sulphate to about 50,000,000 parts of water has
been found fatal to Spirogyra, and one part to
4,000,000 appears to be destructive to the blue-green

Alga-."

* » *

In an interesting paper by Prof. D. H. Campbell in
Tcrreza for June, on the " Resistance of Drought by
Liverworts," which are usually considered to be
moisture-loving plants, attention is drawn to the re-
markable vitality exhibited by the fronds of the " gold
back fern," Gymnogrammc triangularis, which grows in
the neighbourhood of Stanford University, California.
In the resting season the fronds of this fern do not die
down, as is commonly the case in ferns, but they dry
up and persist, and to all appearance are dead. How-
ever, on placing such a frond in water its freshness and
activity are quickly restored by the absorption of water
through its superficial cells. The prothallia of this
fern are able to survive complete drying up. Some
were allowed to remain perfectly dr\' during the whole
summer of 1903, and on receiving water in the autumn
produced numerous young plants. Prof. Campbell
refers to certain devices in Liverworts for preventing
excessive loss of water during periods of drought. In
some the growing point is protected by hairs or scales,
which sometimes secrete mucilage ; while the life of
others is continued by the development of tubers,
which, being more or less subterranean, are less in-
fluenced by a dry season.

The British Association.

1\ a fortnight's time, at Cambridge, the British
Association will once more engage in its annual tourna-
ment of meetings and discussions, and the swing of
the scientific and social pendulum will proceed for a
week as smoothly and hospitably as loyal endeavour
can ensure. That the Right Hon. .\. J. Balfour will
deliver an address as the in-coming president, is a
circumstance which must naturally lend distinction and
fclat to the congress.

So long is it since the Association met at Cambridge,
that it is permissible to indulge in a brief retrospect in
order to call up from the past some of the doings of
the former gathering. The last occasion of meeting
in the university town was in the year 1862, under the
presidency of the Rev. Prof. Willis, F.R.S., Jacksonian
Professor of Natural and Experimental Philosophy.
The Association was then holding its thirty-second
meeting, while it now inaugurates its seventy-fourth.
.Among the presidents of sections was Prof. G. Gabriel
.Stokes, who filled the office for .Mathematics and
Physics, and it was at this meeting that the late
Master of Pembroke presented his valuable report on

Double Refraction. Mr. Francis Gallon — happily
still among us — was president of the section apper-
taining to Geography and Ethnology. Huxley, too,
was there, presiding over the proceedings of Section D.
Tyndall discoursed on the Forms and .Action of Water.
Sir Rutherford .Alcock, in Section E, read a com-
munication on the civilisation of Japan, of which it is
interesting to note that his pregnant sentences stand
forth to-day in honour of Japanese progress. The
race might tell us with truth, he said, that for cen-
turies they had had under their own laws, customs,
and institutions, a degree of peace, prosperity, and
freedom from foreign wars which no country in
Europe had enjoyed during any century of its exist-
ence. They were possessed of so many excellent
qualities and such an aptitude for a higher civilisation
than they had yet attained, that within a very few
years not only might we see them make a great and
unexampled advance, but reach a trade development to
which it was really difficult to fix any limit. Sir Roderick
Murchison read a letter from Livingstone, dated
Shupanga, River Zambesi, informing him in pathetic
terms of the death of his wife, and the darkened
horizon it occasioned. The attendance at the con-
gress reached a total of 1,161.

.As regards the forthcoming assembly, it is reason-
able to expect that the special attractions of Cam-
bridge, coupled with the presence of a Prime Minister,
will raise the inconveniently low average of attendance
which has prevailed during the past three years of the
.Association's meetings. Such a result was seen at its
Oxford gathering in 1894, when the Marquis of Salis-
bury was President. Nevertheless, the British Associa-
tion cannot afford to rely upon quadrennial fortune,
and its friends are concerned not only to secure the
adhesion of a greater number of annual members and
other stead)' supporters, in consonance with the activi-
ties of modern science, but to improve the attendance
at the congresses of the general public. There has
been a steady decline in numbers in recent years. At
Glasgow, in 1901, the attendance was 1,912, and the
receipts ;£r2,o46 ; at Belfast, in 1902, they were, re-
spectively, 1,620, and ;^i,644 ; at Southport, last year,
1,754 and ;^i, 700, the former nearly i,goo less than at
the Southport meeting in 1883. -As a matter of course,
grants for scientific purposes decrease with lessened
prosperity' while other avenues of usefulness remain
unopened. Good attendances prophesy revenue, and a
satisfactory balance-sheet connotes ability to make
allotments for such investigations as are deserving of
recognition and help. Congressional bodies, in fact,
cannot nowadays despise the legitimately commercial
side of their gatherings, and the British Association in
this respect should " wake up."

Certainly no one would wish to extend carping
criticism to an organisation which has done yeoman's
service in the interests of science and of national en-
lightenment. .Apart, however, from the foregoing
considerations, there would appear to be channels for
improvement. Take, for instance, the sectional ad-
dresses. Some of these have latterly become in-
ordinately long, and suggest limitation. Curtailment
in the addresses of a President of the Association
would not be good policy, nor is it required. The man
of science elected to that honourable office has some-
thing to say, and should have space for his utterance.
But those who fill the chairs of the sectional com-
mittees might surely give pause, and compress. The
tendency is towards enlargement, and accompanying
aggrandisement of tyf)e ; this weighs heavily on many

August, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

igi

men, who unwillingly rifle their brains and imagina-
tion for words, words, words. The presidential ad-
dress of 1902 occupied 48 pages of the familiar brick-
coloured volume. In the committees, certain presi-
dential discourses extended to J5, 19 (two cases), and
iS pages of closely printed matter. True, there were
compensations evident in a modest venture of 9 pages
in one instance, and of 8 pages in another.

The one-year rule applicable to the occupancy of the
presidential chair is a golden fetter around the neck of
the Association. In all likelihood the distinguished
men who are at present compelled to retire annually
would be willing — nay, proud — to serve for a longer
term, at anv rate for a biennial period. Under such
conditions they might reasonably hope to be of real
service to the Association each in turn and according
to his opportunities, with corresponding lienelit to the
whole organisation.

The Report of the .Association, containing addresses
and papers read in the sections, we take leave to say,
should be in the hands of members earlier in the year.
At the moment of writing, the volume for the South-
port meeting, held in 1903, has not vet appeared.
Perhaps it will be laid on the table at C.unbridge.

Finally, may we not with advantage quote the ob-
jects of the British Association? They are: — To give
a stronger impulse and a more systematic direction to
scientific inquiry ; to promote the intercourse of those
who cultivate science in different parts of the British
Empire ; to obtain a more general attention to the ob-
jects of science , and a removal of any disadvantages
of a public kind which impede its progress.

[A British Association Siipplctnent <»f "Knowledgi; \ Slientific Xkws*' wil'
be published during August, — Editok.J

REVIEWS OF BOOKS.

New Land. — One might well call Otto Sverdrup's history of
his four years' work on the north coast of Greenland (" New
Land : Four Years in the Arctic Regions." by Otto Sverdrup,
translated trom the Norwegian by Ethel Harriet Hearn ;
2 vols.; London: Longmans, Green, and Co. ; price 36s. net)
an Arctic Odyssey. There is something in this book which
has the space and largeness of purpose of an epic. It is a
large book. It is full of detail. But through it all runs a
singleness of purpose and a sense of vividness which removes
it far from an impression of travel, a record of exploration, a
summary of achievement, and places it before one as a human
document. The story of four years of the life of brave and
earnest men who were hemmed in by the harshest of Nature's
conditions — in journeyings often, in sickness often, in hunger
and thirst often, in perils often. It is on this aspect of the
volume that we would soonest enlarge. Their scientific value
as an addition to the knowledge of the Polar seas and land is
admitted and established ; and they occupy a place by right on
the bookshelves of the geographer, the naturalist, the geologist,
and the meteorologist. But, as Lord Kelvin said when some
years ago the question of an Antarctic expedition was first
mooted, the best ground on which to appeal for help for such
work is the ground of "exploration." That word has a magic
for people to whom scientific results are of little import ;
and " exploration " of that fascinating kind in which the ex-
plorers seem real people of like passions and weaknesses with
ourselves is to be foinul at its best in Captain Otto Sverdrup's
tale. Its introduction is characteristic. Says Captain Sver-
drup : " A few days after our return from the first Norwegian
Polar Expedition, we were lying in Lysaker i5ay unloading the
Fram, when Dr. Nansen came on board. ' Do you still wish
to go on another expedition to the North?' he asked me.
'Yes, certainly,' 1 answered, -if only I had the chance.' He
then told me that Consul Axel Heiberg and the firm of brewers
Messrs. Ringues Brothers were willing to equip a new scientific
expedition with him as leader. The Norwegian Government

gave the Fram, and added ;f iioo to the cost of the enterprise.
As an exploratory expedition, the main object aimed at was the
investigation of the North Coast of Greenland by way of South
Sound and Robeson Channel, and the determination of the
island character of Greenland. The captain was to have a
free hand, and there was no (luestion of reaching tlie Pole.
They were to go for two or three years ; but after passing their
third winter at the head of Choose Fjord, they looked forward
to release ; in the sunuuer they still found themselves ice.
bound. In the sunuuer of iqoi they advanced a distance of
only nine miles, and five miles of an impenetrable l)arricr still
stretched between them and the freedom of the open sea.
It was not till .\ugust, 1902, that the Fiam, having broken the
bonds of her long imprisonment, reached Norway, and received
the welcome that the Norwegians and the whole world was
ready to give them. The expedition had been a great success,
and geographically it had added greatly to our knowledge of
the Peary .Archipelago; had established an outlet from Hayes
Bay; had dtMimited to the west Ellesmere Land,Grinnell L.uid,
Gr.'uit Land: and had l)rought b.iek many valuable geological,
botanical, zoological, and meteorological data all of which are
tabulated and sunmiarised in the capitally translated and
beautifully illustrated volumes that Messrs. Longmans have
published.

But, as we have said, the charm of this work for the general
reader lies in the manner of Captain Sverdrup's telling. He
has the sailor's gift of telling a good yarn, (jiiite early in the
frozen solitudes of the north he encountered a fellow explorer
— a meeting of which we reahse .dike the strangeness and un-
expeeteduess. It was Lieut. Peary, whose ship had been ice-
boimd off Cape Hawkes. But he only stopped a few minutes
— for all the world as if tliey had met on a suburban station
platform with trains to catch. He would not even stay to take
coffee. " I took Peary down to the sledge, and watched him
disappearing at an even pace, driven by his Eskimo driver.

We talked of nothing else, .and rejoiced at

having shaken hands with the explorer, even though his visit
had been so short that we had hardly liad time to pull off our
mittens." The incident is briefly told, but it is wonderfully
vivid ; as vivid as that unconscious word-picture that Sverdrup
draws of his vessel in its ring of ice and silence : " There
lay the Fram stout and defiant like a little fairy house in
the midst of the Polar night." It is in this little fairy liouse
that the four years homely epic of travel takes place. It is here
the Doctor dies, and is buried with tears and prayer. It is
here that they have their merrymakings ; their procession with
banners on Constitution Days (May 17th) ; their newspaper,
" riu- Friciuily One," and their Christmas festivities. Do you
wish to learn how gay and natural a touch there is in this
book ; you will find it it in the pages that tell of Christmas
Day. "When the Christmas tree was brought in, everybody
was quite silent for a moment — and then the merriment broke
loose in earnest. .As it stood there, with its glittering gold and
silver tinsel, and its red and white candles, in the midst of our
darkness here, it seemed to be a greeting from home and from
above. It seemed as if we were being told that there was still
life, and that the light was not really gone. We thought that
we were sitting amid our dear ones, could take them by the
hand, could feel that they really lived ; it was as if happy
thoughts had been sent to us — and thus we li;id to shout for
joy and makt; a horrible noise, uuich worse than our four-footed
friends outside in the snow. And what was a sob within us
found expression in a terrible hubbub, especially when all the
Christmas presents were undone. They were chiefly children's
toys — for men who felt like children ! Drums, trumpets, fire-
works, dolls, Noah's arks, sneezingpowder, scratching powder,
marzipan pigs, and things of that kind. There was merriment
beyond compare, and practical jokes without end."

It was not all simple gaiety among the travellers. The
death of the doctor, followed by another death, plunged them
presently Into depression, a depression deepened by their
comparative ignorance of medicine and the obsession for the
I " oncoming Pol.ar night." But when one of the crew dislocates
his shoulder, the accident, though serious, maintains in Sver-
drup's pages a cheerful view. There is a good deal of humour
in it.

" What had we better do for Olsen's arm ? We found
some diagrams and vari )us directions as to how a dislocation
should be reduced, and after some consideration, chose the
way which seemed the easiest and most simple. The opera-

192

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

tion would have been easy enough had we dared to chloroform
our patient, but we had no desire to attempt such a thing.
Several days had elapsed and the arm was swollen]] and angry.

for that tie could better grapple with. For this purpose we
first tried naphtha, but that did not do ; ho disliked the taste
of it so much that I could not bring myself to force it on him.

The Fram in Winter Quarters.

CaITAIN S\EKl)Rll'.

Start for the Journey.— Spring, 1901.

Inexperienced as we were we should probably torture poor | We had things that tasted considerably better. I sent for a
( )lsen most horribly before we got his arm info place again. liottle of the very best cognac, and began to give hnn dram
I therefore decided to make him thoroughly drunk— the effects I after dram. But it really was too much to expect hnn to drmk

ACGl'ST, 1904.

KNOWLEDGE & SCIENTIFIC NEWS.

193

himself half seas over in dry nips all alone, without any other
diversion, so I sat down and talked to hini about evorythinj;
I could think ot. At first he was very unich taken up with his
arm, but from that we went on to the expetlition in .i;eu< ral,
then to shootins; iu general, and lastly, after inuumerabli! ex-
cursions landed, in the Lofloden Islands iu which he was
patriotic.dly interested. In this way I brought him little by
little into brilliant spirits. He grew livelier at every dram.
Fosheim and Simmons, who had been chosen for the deed of
bone-setting, sat awaiting the propitious monieni, following
with much excitement his various st.ages of development
during om- potations, while I t.alked myself blue in the face to
get him to drink more and hark on the crisis. It was not long
before Olsen himself began to be highly pleased at the whole
performance, decLaring it was the most amusing entertainment
he had ever t.aken part in. When he had swallowed about
half a bottle of brandy we thought he must be about ripe to
be taken. We accordingly placed him on a chest, and the
bone-setters began their work, but no, the collar would not go
in at last, however, we heard with unspeak-
able relief the crack of the arm .as it slipped into its socket.
As for Olsen. notwithstanding all he had taken tiown, it h.ul
not much eflfect on him. While we were doing our work, the
pain and excitement h:id kept him sober, but the instant
the ann was in its .socket he became dead drunk." The
operation in the result proved quite successful. We have not
space for further extracts from this deeply interesting book.
We may say of it in conclusion that its interest and value arises
from its es-sentially human aspect. Even the dogs become the
reader's as well as the writers friends ; and Sverdrup gives us
some quite new views about the l-^skimo. In short, he is a
shrewd observer, a kindly critic, a good writer, and a man to
the backbone. His book is worthy of him.

Zoological Notes for instruction in schools, of a kind which
is likely to attract as well as to instruct children, are being
published by Messrs. .-Vslier and Co., of Coveut Garden. The
plates, large in size and printed in colour, are ( ierman in origin
and manufacture (Schroder and Kull's P>iological diagrams) :
and if, on the one hand, they are w.anting in artistic feeling,
the amount of information they convey of the characteristic
surroundings, occupations, attitudes, anatomy and allied
species of the animals pourtrayed is surprising. It is probable
that such plates leave a stronger impression on a childish
mind than others more artistic or more photographic.

"Our Country's Animals" (Simpkin, Marshall, Hamilton,
Kent and Co.), by W. J. Gordon, is one of a very use-
ful popular series of Natural History. Each volume is
illustrated with coloured plates, so that the amateur observer
of Nature in country rambles may be able to identify the stoat
that runs across his path, the field-mouse that rustles away
into the hedgerow as he passes, or the water-rat that his
coming startles into diving from the bank into the stream. He
may learn, besides, something of their species, habits, and
characteristics.

"The Nature Library" (Fisher Unwin). "Quiet Hours with
Nature," by Mrs. Brightwen, is in p<art republished from the
" Girl's Own Paper." The author's loving observations of bird
and insect life are prettily and sympathetically recorded ; and
her book is as pleasant to read as it must have been to write.

"Nature's Story of the Year." by Charles A. Witchell, of the
same series, also records his observations of Nature, though in
a less sympathetic spirit. No true lover of Nature could shoot
a bullfinch in cold blood because it attacked his fruit trees.
His book nevertheless contains much that is interesting.

" A Modern Zoroastrian " (Watts and Co.), by Samuel f^aing,
deals with scientific and moral questions, and proceeds from
the study of ether and energy to consideration of religions and
philosophies. It is addressed to the general reader.

"Ethics of the Great Religions " (Watts and Co.), by Charles
T. Gorhani, is a useful survey of the principal religions of the
world, and the features they have in common.

"The Ethics of the Dust" (George Allen, pocket edition). In
this little book, which was written in the form of graceful and
fanciful conversations with children, Kuskin attempted to ex-
plain some of the principles of mineralogy and to awaken an
interest in the study of the subject.

"The Lion Hunter" (John Murray), by Hon. Aleyn Gordon
Curnming, which appears in a new edition, is the record of five
years' adventures in the interior of South Africa, covering a
period which began as long ago as October, 1843, so that the
writer traversed much of what was then unknown country.

BOOKS RECEIVED.

(ieography, — We have received lor review the iiiiietietli
edition ot Dr. J.uues Cornwcll's " School Geography ' (Simp-
kin, Marshall, Hamilton, Kent, and Co.). This coiii|)reheiisive
and clearly-arranged text-book should be useful to (enclicrs.
Its facts ;irc judiciously select<'il. and tlie information given
about each country is divicU'd imdrr the heads of physical atid
political geography so that the tcachci's work is simiilificd as
f.ir .IS possible.

fieography for Beginners (Simpkin, Marshall, llaiiiiltou, Kent,
atul Co.). bv the same author, contains (he principal facts in a
simplified form.

Photography.— Practical Enlarging (lliffe and Sons), by John
A. Hodges, appears in a sixth edition. It is intended for the
use of hand camera workers, or those who make use of .iny
small cameras. Bromide enlarging, as tlie most popular
method, is very fully dealt with, and full directions arc also
given for the more el;d>orat<' methods of making enl.irged
negatives.

Practical Slide Making lllilfc and Co.), by G. T. Harris,
F.K.I'.S., is intended to supply trustworthy information con-
cerning all the best known methods of making lantern slide
transparencies; it is clearly written, aiul well adaptc<l lor
pr.actical purposes, with good print and a strong binding.

Photography. — Mr. W. Jerome Harrison's " Photography
for All" (lliffe and Sons) suifers from the defects of its
qualities. It is designed for the instruction of thosf! — among
others — who handle a camer.i for the first time; and it is
sometimes too elementarj'. This would not be a great defect
if it were uj) to date; but that it is not, and the ways it
recomnutids of doing things .-nc not alwavs the best ways.

The Photographic Dealer's Annual (Marshall, Brookes and
Chalkley) is what it aims .at bring — largely .1 trade |)ul)lii-atioii.
But its articles are well written and to the point ; and it is
an extremely useful "who's who" and "what's what" to the
practical [)hotographer.

Engineering. — The Model Engineer Series (IVrcival Marshall
and Co.) is a series of cheapl)' printed and fully illustrated
popular handbooks ; price, fxl. each.

The Locomotive is a simply-written introduction to thi^ study
of locomotive engines, distinguishing between their dilTerent
types ami explaining them.

' X-Rays, by K. F. Howgrave-Graham, A.I.E.IC, aims .it giving
the student some idea of the course of (■x])erinnnt and dis-
covery which led to the present state of scientific knowledge
of Kimtgen rays.

Static Electricity, by Percival G. Bull, M.A.,Oxon., describes
simple experiments illustrating electrical laws and phenomena,
and deals with the various means of producing elfctricity ; and
with electrical attraction and repulsion. It is designed for the
use of young students, and is very clearly and simply written.

Patents Simply Explained gives directions for the patenting
of inventions and the registration of trade marks and designs.

Mechanical Drawing, by F. E. Powell, is designed as a guide
to the apprentice or student, and describes the use of drawing
instruments, and the "reading" of drawings; it also gives
directions for preparing practical illustrative sketches.

Acetylene Gas, by Cyril N. Turner, is a practical handbook
on the uses .and generation of .acetylene gas ; and is designed
to enable amateur meclianics to produce it in an inexpensive
way.

We have received from Mes.sr.s. Adam Hilger, Ltd.,
their new list of .spectroscopes ;md spectroscopic
accessories. The list is well and conveniently arranged
antl the information it affords concerning spectroscopic
instruments alike for general and for special work is of
practical service to the investigator. The most inter-
esting pages are those which reproduce lilm replic.-is
of Rowlandson's diffraction gratings, which are ruled
with 14,438 lines to the inch — a m.arvel of scicntillc
handicraft ; and of the Michelson echelon diffr.ution
gratings.

194

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

Conducted by F. Shii.lington Scales, f.r.m.s.

Gelatin Plates as Light Filters.

A recent number of the "Journal of the Ro3'al Microscopical
Society" t;ives an abstract of a method described b}' a German
writer for maUing gelatin plates which ma}^ serve as substitutes
for glass light filters for microscopical and photomicrographical
purposes. A solution of the best gelatin, such as is used for
making dry plates, is made in the usual way, the proportion to
the water being as i to 200. To the filtered solution 3 cubic
centimetres of 1 to 50 aqueous solution of alum are added.
The films are made by pouring the gelatin on a glass plate
placed on a levelling stand. \Vhen quite dry the gelatin is
overlaid with a film of collodion stained with some aniline dye.
Red plates may be made as follows: Dissolve (i) 2 grni.
aurantia in 40 com. of absolute alcohol, (2) 5 grm. rose Bengal
in 20 com. methyl alcohol. Then mi.\ 20 com. of (i) with
10 com. of (2), and add go com. of 4 per cent, collodion.
Yellow plates can be made by adding 20 c.cm. of a saturated
alcoholic solution of aurantia to So c.cm. 4 per cent, collodion.
The gelatin plates may be doubled so as to strengthen the film,
or one may be placed on either side of the coloured layer.
The advantage of using coloured screens when endeavouring
to photograph ot)jects stained in such a way as to give little
contrast on a photographic plate is obvious to all, and expert
photomicrographers depend largely upon such means of dif-
ferentiating. In an early number of this magazine I hope to
give a brief and elementary account of the ordinary procedure
in photomicrography, mainly for those who are photographers
and who wish to utilise their knowledge in order to photo-
graph microscopic sections, but find their results unsatis-
factory, through want of knowledge of a few elementary rules
of procedure.

Dry and Immersion Objectives.

Several inquiries have been sent to me as to the relative
advantages of dry and immersion objectives, and though the
subject is adequately treated in the various microscopical
text-books, a few words upon the matter may be of service.
Let us assume that an extraordinarily wide-angled dry lens
can embrace an angle of 170° from an object placed un-
covered on the slide, though, of course, so large an angle as
this is really barely possible. Then a cover-glass placed over
the objective will produce a certain amount of refraction,
according to the well-known law that rays of light from a
medium (in this case glass) entering another less dense (in
this case air) are refracted away from the perpendicular.
By this refraction a large portion of the extreme rays, which
ought to enter the objective, will be refracted, some being
even totally reflected, and so fail to enter it. If a denser
medium were to take the place of the air, this refraction
would be minimised, and if it were as dense as the cover-
glass, it would be practically non-existent. This resolves
into the fact that an oil-immersion objective of 82", a
water-immersion of 97', and a dry lens of 170', all admit ap-
proximately the same amount of light. Therefore a water-
immersion, and still more an oil-immersion can be made to
admit light of an angle much greater than the widest angled
dry lens. There is therefore a great gain of light, and with
the increase of aperture there is a corresponding gain of
resolving power. There is yet a further gain of working dis-
tance. There is still a further gain, sometimes overlooked,
due to the fact that the intensity of the rays are less as they
become more oblique, but that they increase in intensity
according to the density of the medium, in a ratio, in fact,
that is measured by the squares of their refractive indices.

linough has been said to show the advantage of the immer-
sion system of objectives. It follows naturally that the term
angular aperture no longer expresses the value of an objective,
and thus a new system of rating has sprung into existence, due
to Professor Abbe, which takes into consideration the refrac-
tive index of the medium, whether air, water, or oil, as well as
the angular aperture. The formula is ;; si;; m, where n is the
index of refraction of the medium in front of the objective,
and ti the sine of half the diameter of the emergent pencil of
light at the back of the objective. This is the " Numerical
Aperture," or N.A. Finally, there is yet another advantage.
Any variation in the thickness of the cover-glass in a dry lens
upsets the corrections of the objective, and must be corrected
by a collar which adjusts the position of the individual lenses
which make up the objective, or by an adjustment of tube
length. Water has a refractive index nearer to the cover-
glass than air, and therefore the necessary corrections are
much less serious ; but cedar oil has almost exactly the same
refractive index as crown glass, and so there are practically
no corrections required. Of course, immersion-lenses are
always high powers, and equally, of course, it is not quite as
convenient, and is now and again impracticable, to use such
lenses. It is scarcely necessary to add that a dry lens
cannot be used as an immersion lens, nor an immersion lens
in any other medium than that for which it is constructed.
Immersion condensers are made in order to reduce aberra-
tions, and to enable a cone of light to be passed which is pro-
portional to the wide apertures of immersion objectives, and
with an oil immersion condenser, an oil immersion objective,
and an object mounted in Canada Balsam, we have a con-
denser, a connecting medium, a slide, a moimting medium, a
cover-glass, again a connecting medium, and finally an objec-
tive, which arc. to all mtents and purposes, one homogeneous
whole.

Wa.tson's "Fa.cility" Object-Changer.

Messrs. W. Watson and Sons have sent for inspection a
new object-changer of novel construction. It is square in
shape and screws on to the end of the draw-tube in the ordi-
nary way. On the under side are a pair of opposite jaws, a
quarter of an inch wide, which open by means of the handle
shown in the illustration, and when released eng.age the threads
of the objective screw and carry it up to the shoulder where it

is firmly and squarely held in place. It is made of Magnalium
and so is very light ; it is only half an inch thick, and it pro-
vides a rapid and easy method of changing objectives. Most
workers have found that they possess one or more objectives
whose screws are not cut strictly to the proper gauge, and to
obviate this Messrs. Watson provide rings of absolute gauge to
fit such objectives, and ensure accurate gripping in the jaws
of the object-changer. These rings do not interfere with the
fit of the objective in its box.

Roya-l Microscopica.1 Society.

June 15th.— Dr. Dukinfield H. Scott, F.K.S., President, in
the chair. Mr. T. H. Powell exhibited PUurosif^ina aii^iilatiim
under a ,i„-inch, 1-35 N.A. apochromatic homogeneous immer-
sion objective made by him. Professor Hartog exhibited a
slide prepared and lent to him by Professor Vejdovsky showing
the first segmentation spindle and centrospheres in the embryo
of Khynchelinis. This was so large as to be visible with a
pocket lens and was distinctly shown under a J, -inch objective
and " B " ocular. Mr. Beck exhibited a portable microscope
designed by Mr. Arthur Hollick. It was daily used for the
examination of botanical subjects, but was equally useful for
other purposes. The mirror was so mounted that it could be
used above the stage for illuminating opaque objects, swing-
ing on a centre that was at the level of the object. An ingeni-
ously contrived rotating cell, made of cardboard, forming a
convenient revolving object holder, and a simple method of

ArcvsT, 1004.1

KNOWLEDGE 8z SCIENTIFIC NEWS.

195

mountins; in pillboxes were described. Another point ol
interest w.isthe coniinj? down of the objective to snch size as
to admit as imieh, and no more, light than could be utilized
by the back lens : this reduction of the front of the objective
facilitated the illumination of opaque objects. Professor
J. D. Everett read his paper, entitled " .\ direct proof of
.\bbe"s theorem on the microscopic resolution of gratings."
In the subsequent discussion Mr. J. W. Gordon, Mr. Conrad
Beck, and Mr. Kheinberg took part. Mr. Beck explained
.\bbe"s experiment with a grating on .the stage showing doub-
ling of the lines by means of a triple slit in the focal plane of
the object glass. This he had brought at Professor Everett's
request in illustration of the paper. Mr. Kheinberg followed
with some remarks on the influence on image gratings of phase
difference among their spectra, which he illustrated by an
arrangement he had prepared of a microscope that showed the
movement of lines in the image of a grating by creating a
phase difference amongst the spectra in the back focal plane
of the objective by means of an .\bbe glass-wedge compensa-
tor. Mr. F. \V. Millett's paper, the 16th of the series, on the
recent Foraminifera of the Malay .\rcliipelago was taken as
read. Mr. F. Enock then gave his lecture on '■ Nature's
Protection of Insect Life," which was illustrated by a fine
series of lantern slides of colour-photographs of living insects.
The following were elected Honorarv Fellows of the Society :
Gaston Bonner, Jacques Brun.Vves Delage, S. Ramon yCajal,
B. Renault, J. J. Harris Teall, Sylvanus R. Thompson, and
M. Treub.

Quekett Microscopical Club.

The 415th ordinary meeting of the Club was held on
June 17, at 20, Hanover Square, \V., the President, Dr. E. J.
Spitta, V.P.R.A.S., in the chair. An unusuallv large number
of new members were balloted for. .Mr. C. D. Soar, F.R.M.S.,
read a paper descriptive of two new Fresh-water Mites,
Psiiidd/cltria scoiirfieldi, discovered in Cwmm Glas, North
Wales, by himself, and Midccpsis crassipcs. found at Oban by
Mr. Taverner. The President then gave an interesting lecture
and demonstration " On a Method of Suiting Screens for the
Photomicrography of Stained Bacteria." He was assisted by
his son. Dr. Harold Spitta, who exhibited a number of lantern
slides and diagrams illustrative of the method and its results,
and by Mr. Conrady, who manipulated a second lantern fitted
with a large spectroscope, by means of which a series of
beautiful and interesting spectra were thrown upon a sepa-
rate screen. After comparing and contrasting the differences
between the eye and the photographic plate in the matter of
colour sensation, Dr. E. J. Spitta went into a comparison of
the various orthochromatic plates upon the market. By test-
ing each plate under long and short exposures with a spec-
troscope, he found a wide difference in their relative sensibility
to colour, a difference which he illustrated by means of photo-
graphs of the spectrum taken on each kind of plate. Having
ascertained by this means the limit of their sensitiveness in
the presence of colour, which he termed the " eye " of the
plate, he was enabled to construct contrasting screens by
means of which the maximum contrast was obtainable.
Photographs of bacteria stained with Lofiler'? blue, gentian
violet, and carbol fuchsin, the three principal bacteriological
stains, were exhibited, taken with and without the contrasting
screens. The results were most striking, the improvement in
detail and definition being very marked.

H. W. Harvey, Norfolk,

I would suggest your getting M. C. Cooke's " Microscopic
Fungi," which forms a good introduction to the study of the
subject.
T. H. Astbur>-, Wallingford.

In answer to your (|uery as to Mr. Warburton's article on
"Mites," Mr. Warburtoii says he uses concentrated carbolic
acid for clearing. I am aware that this sometimes leads to
difficulties in subsequent mounting in Canada balsam, but
Mr. Warburton says he has no difficulty with it. With regard
to the parasitic growths upon Piiniiis prolifcricornh, if you
will send me the Iieetle I will see what I can do with if.
.Miss B. B. Bryant, Bath.

By the blow-fly Calliphora vamiioria is understood. It
has a yellow, golden, or white head, brown eyes, black thorax,
and blue abdomen with black stripes and long black hairs.

i'hc tlesh-rtv is S,ii\iipluti^(i caninriu. It has .a head yellow in
front, with feathery .intenn;e, reddish eyes, grey thorax, with
longitudinal black lines, black abdomen with four square
white spots on each segment, .uid bl.ick hairs on .all the body.
Dr. Sharp has kindly given nie the following particulars : " By
blow-flies and meat-flics I think people mean the same thing,
viz., the blue CuUiphoni s. Hut the flc^sh-fly is a very different
insect — a grey-striped and black insect with red eyes — Surcoph-
af;a carnaria. There is rather a difficulty .as rcg.irds Sarcopliuf^a,
because there are different species : though horribly awake they
apparently difter greatly in economics, the .S'. carnciria being
viviparous. As regards the blow-flies, both Calliphova voiui-
toriii and C. t-iytlinici-plui!ii are equally common here; one has
a yellow face with black beard on if, th(^ other a black face
with yellow hairs. No doubt witli most people they pass as
all C. ervthroccphala. Siircopliaga has the abdomen mottled a
sort of s<]uare pattern, it has very large pulvilli on the feet, is
a quite different shape from Calliphora, and keeps in the
countrv on the look out for carcases. There is still a great
deal of much interest to be discovered about these coinmon
flies, which, though disgusting to most people, are pliysiologic-
ally at the top of the animal kingdom." " A List of British
Di'ptera," by G. H, Verrall { jnd edition) may be procured from
the author, Sussex Lodge, Newmarket. With regard to
mounting flies whole, I would suggest your trying a weaker
solution of potassium hydrate and longer immersion. The
object of this soaking is mainly to dissolve out the contc'Uts of
the abdomen, &c., after which the object is washed first
thoroughly in wafer and then dehydrated in alcohol, and
finally so.aked (for a few days, if necessary) in turpentine to
make it transparent, then cleared in clove-oil and mounted in
Canada balsam. If this does not prove satisfactory, I would
suggest treating the wings separately and mounting on the
same slide, or mounting another fly dry fi)r comparison.
A. Morley Jones, Ealing.

Vour query has not reached me before, but you do not
say what are the Zoophytes to which you refer. Generally
speaking, the method of mounting would be narcotisation by
cocaine by gradually adding a one per cent, solution to a
small quantity of water containing the specimens, or killing at
once by a drop of osmic acid, washing in water, staining if
requisite, again washing, and finally mounting in glycerine
jelly.
George Phelps, Warminster.

I am afraid the only reference I can give you on the subject
of Trombidiid mites is to the article on Mites in "Carpenter."
Mr. Michael's monographs in the Ray Society's publications
deal only with the Orihatidie and cheese-miles. The forth-
coming volume of the Cambridge Natural History will have a
short account of the Tromhidiidw, and I understand from Mr.
Soar that a number of " Das Tierreich" shortly to be published
will contain a full list and description of every species. As I
have said to another correspondent, the literature with regard
to mites is in a very incomplete state.
A. Robinson, Portsmouth.

An objective corrected for a short tube docs not perform as
well with the long tube; but it is so much a matter for a
critical eye and critical illumination that I fear I cannot advise
you how to ascertain the length of tube for which your objec-
tives are corrected if your own work has not shown it to you.
I would suggest, however, your obtaining a slide of the pro-
boscis of a blow-fly, and,'using the edge of the lamp-flame,
carefully focus first the objective upon the slide, and then the
lamp flame by means of the condenser, so that with a mode-
ratelv low po%ver a distinctly marked band of light lies across
the field. The fine hairs on the tip of the proboscis (not the
long ones on the edge) are those to be looked at, and the iris
diaphragm must be sluit down just enough to cut off any excess
of light, and not enough to cause any thickening of the fila-
ment-like points of the hairs, or any refraction rings around
them. Then use the highest-powered eyepiece you have, and
note whether the objective performs best when the tube is
fully closed or fully extended. As a matter of fact, nearly all
students' series of objectives, whether of English or Continental
make, if comparatively recently made, are corrected now for
the short tube.

[Communications and enquiries on Microscopical matters arc invited,
and should be addressed to F. Shillington Scales, "Jersey," St.
liarnalias Road, Cambridge .]

ig6

KNOWLEDGE & SCIENTIFIC NEWS.

[August, 1904.

The Face of the Sky for
August.

By \V. Shackleton, F.R.A.S.

The Sux. — On the ist the Sun rises at 4.24, and sets
at 7.47; on the 31st he rises at 5.12, and sets at 6.4S.

Sunspots, faculaE', and prominences have been fairly
conspicuous of late.

The positions of spots with respect to the equator
and poles may be derived by employing the following
table : —

Date.

Axis inclined from N.

point.

Sun's equator.

Aug. I ..

11° o'E.

5° 55'

II ..

14° 47'

6° 32'

,, 21 ..

iS° 9'

6° 58'

.. 31 ■•

21= 2' E.

7' 12'

The Moon- :-

Date. Phases.

H. M.

Aug. 4 . . d Last Quarter
II . . • New Moon
iS .. J) First Quarter
,, 26 .. 0 Full Moon

2 3 p.m.

0 58 p.m.
4 27 am.

1 2 a.m.

Au=.

Perigee (222,; ju ,
Apogee (252,500

18 a.m.
12 am.

The Planets. — Mercury is an evening star, setting
about 8.40 p.m. on the ist. He is in aphelion on the
17th and at greatest elongation on the 20th, hence the
proximity of the time of aphelion to that of greatest
elongation makes the angular distance from the sun large,
and amount to 27' 24' E ; the position of the ecliptic in the
evening sky at this time of the year, howe\er, counter-
acts the otherwise fa\ourable coincidence of greatest
elongation and aphelion.

\'enus is an evening star in Leo, setting abeut 7.50
p.m. on the 15th.

Mars is a morning star in Cancer, rising about two
hours in advance of the Sun.

Jupiter rises about 10.15 p.m- on the ist, and about
8.30 p.m. on the 31st. Towards the end of the month he
will be the most conspicuous object in the sky about
10 p.m., looking east.

He is at the stationary point on the 20th, after which
his motion is retrograde or westerly.

The equatorial diameter of the planet on the 17th is
44"-8, whilst the polar diameter is 2"-g less.

Saturn is now well placed for observation, being a very
conspicuous object in the S.E. at 10 p.m., not very high
up. The planet is in opposition to the Sun on the loth,
hence this is the most favourable time for making obser-
\ations of the white spots which were seen last year and
used for the determination of the period of rotation, giving
a value of 10 h. 38 min.

The polar diameter of the ball is i7"-4, whilst the major
and minor axes of the outer ring are 43"'4 and ii"*4
respectively. The northern surface of the ring is pre-
sented to us at an angle of 15 to our line of vision.

Uranus is on the meridian about 8 p.m. near the middle
of the month, when he is about 10 minutes west of the
star 4 Sagittarii. His path on the borders of Ophiuchus
and Sagittarius may be seen on reference to the chart
appearing in the June number.

Neptune is not suitably placed for observation, rising
about 5 a.m.

Meteors : —

Date.

Radiant.

Aug. 10-12
Aug 21-25

a d

45- +57^^

291° -j-Go"

Great Perseid shower: radiant
moving E.N.E. about i''
per day.

0 Draconids ; bright slow
meteors.

The Stars : —

About 9 p.m. at the beginning of the month the con-
stellations to be noticed are : —

Zenith . Lyra ( Vega), Hercules, Draco.

South . Sagittarius, Scorpio, Ophiuchus, Aquila;

Aquarius and Capricornus to the S.E.
West . Bootes, Corona; Great Bear to the X.W.,

Virgo and Libra, S.W.
East . Cygnus, Delphinus, Pegasus, Aries;

Andromeda and Cassiopeia to the N.E.
North . Ursa Minor, .Vuriga (Ca/^/Zrt on horizon).
Minima of Algol occur on the 14th at 11.22 p.m. and
on the 17th at 8.10 p.m.

Telescopic Objects: —

Double Stars: — Polaris, mags. 2-i, 95; separation
i8"-6. The visibility of the small star is used as a test
for a good 2-inch object glass.

i Sagittae XIX.'' 45'", N. 18" 53', mags. 5, 10; separa-
tion 8"-6.

a}, a- Capricorni XX.*" 12", S. 12' 51', mags, a' 4.5,
a'- 3'8 ; naked eye double, separation 373", very easy with
opera glasses.

7 Delphini XX.^ 42™, N. 15' 46 , mags. 4-1, 5-0 ; sepa-
ration ii"-8. Very pretty double for small telescopes;
brighter component yellow, the other light green.

Nebula;, &ic. — Dumb Bell nebula in \'ulpecula, nearly
4^ due north of y Sagittae. Rather faint object in a
3-inch.

(M 8) Cluster in Sagittarius; large luminous field of
small stars ; fine object in pair of field glasses. .About
a degree E. of the star 4 Sagittarii and near to the
present position of Uranus.

.Messler, of Berlin, Germany, and Gaumont, of Paris,
France, have finally succeeded in combining the grapho-
phone and the biog'raph so that perfect synchronism is
attained. It is now possible to see the pictures of a
cavalrj' drill and hear the commands as they issue from
the officer's lips. .\ singer accompanies her gestures
with the proper words and tones, creating- an illusion so
perfect as to make it in many cases almost impossible to
believe that what is seen is not life itself. It is hoped
that the invention may be so developed that it will be
possible to reproduce on the screen .scenes from all coun-
tries, accompanied with the appropriate sounds and
languages. The educational value of such a perform-
ance would be much greater than that of the unaccom-
panied, silent biograph.

KDomledge & Seiendfie fleuis

A MONTHLY JOURNAL OF SCIENCE.

Conducted by MAJOR B. BADEN-POWELL and E. S. GREW, M.A.

SIXPENCE.

Vol. I. No. 6. [NKW series.] SEPTEMBER, 1904. [s, ,!*;,",''';"' iVaii 1

CONTENTS AND NOTICES.— See Page VII.

THE BRITISH ASSOCIATION

Presidentia^l Address.
SectionsLl Addresses. .

One of the most interesting and most largely attended meet-
ings of the British Association during recent years began its
sessions at Cambridge on Wednesday, the 17th of August.
The unique position which Cambridge occupies in the history
of science, and the great part which she has played in its de-
velopment, joined to the attrac-
tions which an ancient Univer-
sity always extends to visitors,
drew a representative gathering
not only of British men of
science, but of distinguished
foreign physicists, zoologists,
biologists, and economists. The
Presidential address of the Right
Hon. A.J. Balfour was delivered
on Wednesday evening, and was
heard by an audience that was
as brilliant as it was crowded.

The President, the Right Hon.
A. J. Balfour, said that the
meetings of the -Association had
been held for the most part in
crowded centres of population
where the surroundings never
permitted them to forget, were
such forgetfulness in any case
possible, how close was the tie
that bound modern science to
modern industry, and that was no
doubt as it should be ; the inter-
dependence of theory and prac-
tice could not be ignored without
inflicting injury on both, and he
was but a poor friend to either
who undervalued their mutual
co-operation. Yet, after all, since
the British Association existed
for the advancement of science,
it was well that now and again
the members should choose their
place of gathering in some spot
where science, rather than its
applications, knowledge not
utility, were the ends to which
research was primarily directed.
If that were the case, surely no
happier selection could have been made than the ([uiet courts of
that ancient university — for there, if anywhere, they trod the
classic ground of physical discovery. Unless he was led astray by
too partial an affection for the old university, there was nowhere
to be found in any corner of the world a spot with which had
been connected either their training in youth, or by the labours

I'hiito. hij thf London Sti'ri'osrojnr t'o ]

THE RIGHT HON. A. J. BALFOUR, M.P., President

of their mature years, so many men eminent as the originators
of new and fruitful physical conceptions. He said nothing of
Bacon nor of Darwin, the Copernicus of biology, for his sub-
ject was not the contributions of Cambridge to the general
grosvth of scientific knowledge. He was concerned rather

with the illustrious physicists who
had learned or taught within a
few hundred yards of that spot
— a line stretching from Newton
in the Seventeenth Century,
through Cavendish in the Kigh-
teenth, through ^'oung, Stokes,
and Maxwell in the Nineteenth,
through Kelvin — who embodied
an epoch in himself — down to
Rayleigh, Larmor, and the scien-
tific school centred in the Caven-
dish Laboratory, whose physical
speculation bade fair to render
the closing years of the old cen-
tury and the opening years of
the new as notable as the great-
est which had preceded them.
What was the task which the.se
physicists had set themselves to
accomplish ? Whither led their
•' new and fruitful conceptions ? "
Physics was often described as
the " discovery of the laws con-
necting phenomena." That was
a misleading expression, because
the phenomena investigated were
things that could not appear to
beings so poorly provided with
sense perception as ourselves.
Hut apart from the linguistic
error, was it not also inaccurate
to say that a knowledge of
Nature's laws was all we sought
when investigating .Nature ? The
physicist sought for something
deeper than the laws connecting
possible objects of experience.
His object was physical reality,
which might or might not be
capable of direct perception
— a reality which was in any case independent of it ; a
reality which constituted the permanent mechanism of that
physical universe witli which our empirical connection was so
slight and so deceptive. If, then, one of the tasks of science,
and more particularly of physics, was to frame a conception
of the physical universe in its inner reality, then any attempt

ig8

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

to compare the different modes in which from time to time
this intellectual picture has been drawn could not fail to
suggest questions of the deepest interest. With those which
were purely philosophical the character of the occasion pre-
cluded him from dealing : with those that were purely scientific
his own incompetence forbade : but there were some questions
near enough the dividing line to induce one to consider them.

He would take, therefore, for his point of departure the
closing years of the Eighteenth Century, a little more than
a hundred years after the publication of Newton's'- Principia.''
If at that period the average man of science had been asked
to sketch his general conception of the physical universe he
would probably have said that it consisted essentially of
various sorts of ponderable matter, scattered in different com-
binations through space, exhibiting various aspects, but through
every metamorphosis obedient to the laws of motion ; always
keeping its mass unchanged, and exercising at all distances a
force of attraction on other material masses, according to a
simple law. The late Eighteenth Century physicist might
have added the so-called " imponderable " heat to the categorv
of ponderable matter, together with the two ■• electrical fluids."
and the corpuscular emanations supposed to constitute light.
In the universe as thus conceived '-action at a distance " was
the most important form of action, the principle of the con-
servation of energj' was undreamed of. clectricitv and mag-
netism played no great part in the whole of things, nor was a
diffused ether required to complete the machinery of the
universe. Within a few months of the date assigned to the
hypothetical physicist came an addition to this general
conception of the world designed profoundlv to modify it.

A hundred years ago Voung opened, or re-opened, the great
contro%-ersy which finally established the undulatory theory of
light, and with it a belief in an interstellar medium of which
undulations could be conveyed. But this discoven,- was much
more than the substitution of a theory of light consistent with
the facts for one which was not. Here was the first introduc-
tion of a new and prodigious constituent — the ether — into the
scientific world picture. Unending space was no longer thinh-
strewn with suns and satellites. It was now filled with a con-
tinuous medium. It gave promise of strange developments.
It could not be supposed that the ether, if its reality were once
.admitted, existed onlv to convey through interstellar space the
vibrations of light — the vibrations which happened to stimulate
the optic nerve of man. Intended originally to fulfil that
function, to that it could never be confined. It conveyed light
and radiant heat and electrical waves and Hertzian waves
and waves to which the human perception makes no response.
But that was not all or nearly all. If we jumped the centurv
from 1S04 to 1904 and attempted to give in outline the
scientific world picture as it now presented itself to contem-
poran.- speculation, we should find not only that it bad
been greatly modified by new laws and new disco\eries,
but chiefly by the more and more important part which elec-
tricity and the ether occupied in any representation of ultimate
physical reality. Electricity in 1700 was no more to the
philosophers than the hidden cause of the insignificant pheno-
mena by which amber or glass, when rubbed, attracted small
objects brought into their neighbourhood. It was fifty years
before its effects were perceived in the thunderstorm ; a hundred
years before it was detected in the form of a current : one hundred
and twenty years before it was connected with magnetism ; one
hundred and seventy years before it was connected with light
and with " ethereal radiation." But to-day there were those,
the protagonists of the electric theory of matter, who regarded
gross matter as the mere appearance of which electricity was
the physical basis. Such theorists thought that the elementarv
atomwasitselfbutacollectionof monads or electrons, which are
not electrified matter but electricity itself — that those systems
differed in the number and arrangement and relation of their
electrons, and that on those differences depended the various
qualities of atoms. Finally, that, while in most cases those
atomic systems might maintain their equilibrium for periods
that seemed almost eternal, yet they were not less obedient to
the law of change than the everlasting heavens themselves.

But if gross matter was a grouping of atoms, and atoms
were systems of electrical monads, what were these electrical
monads ? It might be that, as Dr. Larmor had suggested,
they were but a modification of the ether — a modification
roughly comparable to a twist or a knot in the ether.
Whether that were accepted or not. it was certain that these

electrical monads could not be considered apart from the
ether. Their qualities depended on their interaction with it.
Without it an electric theon.- of matter was impossible.
Surely here was the most extraordinary of revolutions. Two
centuries ago electricity seemed but a scientific toy. It was now
thought by many to constitute the reality of which matter was
but the sensible expression. It seemed possible now that it
might be the stuff out of which that universe was wholly built.

Nor were the collateral inferences less surprising. It used
to be thought that mass was an original property of matter ;
neither capable of explanation nor requiring it ; in its
nature essentially unchangeable ; sufl'ering neither augmenta-
tion nor diminution under the stress of any forces to which it
could be subjected ; unalterably attached to and identified
with each material fragment. But if the new theories \\ ere
accepted, those views must be revised. Mass was not only
explicable, but explained. So far from being an attribute of
matter, it was due to the relation between the electrical
monads of which matter was composed and the ether in which
thej- were bathed. So far from being unchangeable, it changed
when moving at very high speeds with every change in its
velocity. Perhaps, however, the most impressive alteration
in the cosmical picture was in its view of the distant suns and
their satellites — the stars visibly incandescent and in process
of transformation from the nebula whence they sprang to the
frozen darkness to which they were predestined. What of
the invisible multitude of heavenly bodies in which the process
had been completed ? According to the ordinary view they had
reached a state when all possibilities of internal movement were
exhausted. At the temperature of intersteUar space chemical
action and molecular action would be impossible; and the
stars and their constituent elements had no source of
replenishment of their exhausted energ\- except by some
celestial collision. But this view must be profoundly modified
if we accepted the electric theory of matter. We could no
longer hold that if the internal energy of a sun were as far as
possible converted into heat which could be radiated away,
then the sun"s whole energv- would be exhausted. On the
contrary, the amount thus lost would be absolutely insignifi-
cant compared with what remained stored up within the sepa-
rate atoms. The system in its corporate capacity would become
bankrupt. The wealth of its individual constituents would
remain undiminished. They would be side by side without
movement, without affinity, yet each, however inert in external
relations, the theatre of violent forces, by the side of which
those that shattered a world and revealed it as a flaming new
star to the astronomer's telescope were negligible.

In common w ith all living things, we seemed to be practically
concerned with the feebler forces of Nature and with energy in
its least powerful manifestations. Chemical affinity and co-
hesion were, on this theory, no more than the slight residual
effects of the internal electrical forces which kept the atom in
being. Gra\itation. though it were the shaping force that
concentrated nebute into suns and satellites, was trifling com-
pared w ith the attractions and repulsions between electrically-
charged bodies : and those again sank into insignificance
beside the attractions and repulsions between the electrical
monads themselves. The irregular molecular movements
which constituted heat, on which the very possibility of organic
life seemed to hang, could not rival the prodigious energy-
stored within the molecules themselves. Vet this prodigious
mechanism seemed outside the range of our immediate inte-
rests. We li\ed merely on its fringe. It had no promise of
utilitarian value ; we could not harness it to our trains, ^"et
not less did it stir the imagination. Its marvels were greater
than those which in the starry- heavens had from time
immemorial moved the worship and wonder of mankind.

The President went on to comment on the acute intellectual
gratification which the theorv- awakened, a satisfaction almost
cESthetic in its intensitj' and quality. It was, he said, a senti-
ment possibly derived from an instinct, not hghtly to be
ignored, in favour of the belief that the material world should
be a modification of a single medium rather than a composite
structure. These obscure intimations about the nature of
reality deserved, he thought, more attention than had yet been
given to them. That they existed was certain. The difficulty
that arose was when experience apparently said one thing and
scientific instinct persisted in saying another. That these new-
views of matter diverged violently from those suggested by
ordinary- observation was plain enough. No scientific educa-

Sept., 1904.]

KNOWLEDGE & SClENtlFIC NEWS.

199

tion was likely to make us in our unreflective moments regard
the solid earth on which we stood, or the organised bodies
with which our terrestrial fate was so closely bound up. as
consisting only of electric monads. Not less plain was it that
an almost equal divergence was to be formed between these
new theories and that modification of the "commonsense
view of matter " with wliich science h.ad lieen in the main
content to work. What was this modification of common
sense? It was roughly indicated by an oUl philosophic de-
duction drawn between what were called tlio " primary "
and "secondary " qu.alities of matter. The primary qualities.
such as shape and mass, were supposed to possess .m exis-
tence quite independent of the ob.server. The secondary
qualities, such as warmth and colour, were supposed to have
no such independent existence, being no more than the resul-
tants due to the action of the primary qualities on our organs
of sense-perception. .\nd there, no doubt, common sense and
theory parted company. Such was the theory on which
science had in the main proceeded. It was with matter thus
conceived that Newton experimented. To it he applied his
laws of motion; of it he predicted tmiversal gravitation.

Norwasthe case greatly altered when science became.is much
preoccupied with the movements of molecules as it was with
that of planets. For molecules and atoms were at least pieces
of matter, possessed of those '• primary " qualities supposed to
be characteristic of all matter. Hut the electric theory carried
us into a new region .altogether. It was not content to account
for the secondary qualities by the primary; or the behaviour of
matter in atoms. It analysed matter whether molar or mole-
cular into something that was not matter at all. The
atom was now no more than the relatively vast theatre
in which the electric monads performed their evolutions ;
while the monads themselves were not regarded as
units of matter, but as units of electricity. So that matter
was not merely explained, but was explained away.
The point to which he desired to call attention was not to
be sought in the divergence between matter as thus conceived
and matter as the ordinary man supposed himself to know it,
but to the fact that the first of those two quite inconsistent
views was wholly based on the second. That was surely
something of a paradox. We claimed to found all our scientific
opinions on experience, and the experience of the universe
was our sense-perception of the universe ; yet the conclusions
which thus professed to be founded on experience were to all
appearance fundamentally opposed to it. Our knowledge of
reality was based on illusion. The very conceptions we used
in describing it to others, or in thinking of it ourselves, were
abstracted from anthropomorphite fancies which science for-
bade us to believe and Nature compelled us to employ. An
added emphasis was given to these reflections by a train of
thought that had long interested him, though he acknowledged
that it had never seemed to have interested anyone else.

Sense-perceptions supplied the premises from which we drew
all our knowledge of the physical world. From them we learned
that there was a phj'sical world. But in order of causation
they were effects due to the constitution of our organs of sense.
What we saw depended not merely on what there was to be
seen, but on our eyes. What we heard depended not merely
on what there was to be heard, but on our ears. Now eyes
and ears had been evolved by the slow processes of natural
selection. .'\nd what was true of sense-perception was also
true of the intellectual powers which enabled us to erect on the
frail and narrow platform that sense-perception provided the
proud fabric of the sciences. Hut natural selection worked
only through utility. Our powers of sense-perception and
calculation were worked out ages before they were effectively
employed in searching out the secrets of physical reality.
Natural selection possessed no power of prevision. Our organs
of sense-perception were not given us for purposes of research,
nor was it to aid us in meting out the heavens or dividing the
atom; but our powers of calculation and analysis were evolved
from the rudimentary instinct of the animal. It was presum-
ably due to this that the beliefs of all mankind about the
material in which it dwells were not only imperfect, but
fundamentally wrong. It might seem singular to say that
down to, say, five years ago our race had without exception
lived and died in a world of illusion, and that its illusions were
not about things transcendental or divine, but about what it
said and handled, "the plain matters of fact," among which
commonsense daily moved with its most confident step and

its most self-satisfied smile. And that was either because too
direct a vision of physical reality was a hindrance in the
struggle for existence or else because with so imperfect a material
as livuig tissue it was impos.sihle to arrive at right vision.

If that conclusion were accepted its consequences ex-
tended to other organs of knowledge besides those of
perception. Not merely the senses but the intellect nuist be
judged by it. Considerations like these did luidoubtedly
suggest a certain mevitable incoherence in any general scheme
of thought which was built out of materials provided by natural
science alone. Extend the boundaries of knowledge as far .as
you pleased; draw the picture of the universe as you would;
reduce its infinite variety to the all-pervading ether; trace its
evolution to the point of the developnu:nt of the race and the
birth of the scientific handful of men who looked round on
the world, and, seeing, judged it and knew it for what it was—
perform all these things, and though you might indeed have
attained to science, in no wise would you have .-ittained to a self-
suHicing system of beliefs. One thing at le.ist would rem.iin
of which tiiis long-drawn suspense of causes and effects gave
no satisfying explanation; and that was knowledge itself. In
conclusion, the President asked the forgiveness of his audience
if he had overstepped the; ample boundaries within which the
searchers into Nature carried on their labours. His first desire
had been to rouse in those who, like himself, were no special-
ists in physics the same absorbing interest in what he felt to
be the most far-reaching speculation about the physical uni-
versi^ Ih.at h.id ever claimed support ; and if in doing so he
h.ad been tempted to show that the farther such speculations
were carried the more needful it was to complete our scheme
of thought by considerations not drawn from his mere exami-
nation of the'inanimatc world, even those who least agreed might
perhaps be prepared to pardon.

Section A.— Mathematical a^nd Physical
Science.

Professor Hokaci; Lamb, M.A., LL.D., F.R.S., was born
in 1849; was Second Wrangler at Cambridge in 1872 ; Fellow
and Assistant Tutor of Trinity, afterwards Professor of
Mathematics at Adelaide 1876-1S85) and at Manchester. He

Plioto. Ii!i I.ii/ii!i,lle, l.ta.\

PROF. HOKACli LAMB.

200

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

h:is written on various branches of mathematical physics, and
has pulilished a bool< on Hydrodynamics. He was elected a
Fellow of the Koyal Society in iS(S4 ; Koyal Society Medallist,
1902 ; and is Honorary LL.D. of Glasgow and D.Sc. of
Oxford. Professor Lamb is President of the London Mathe-
matical Society.

Professor Horace Lamb's address to the Mathematical and
Physical Section was a consideration of the place occupied by
the late Sir Gabriel Stokes, who took the presidential
chair of the Section when last the Hritish Association met at
Cambridge, in the development of iMathematics. The aspect
of Stokes' work to which attention was specially directed was
its historic or evolutionary relation to the work of his prede-
cessors and followers in that field. The review of this work
led to the consideration of the question of the part which
abstract conceptions played in the development of science; of
the uses, for example, of theories of matter or of electricity, of
the atom, of the ether, of tbe universe. Professor Lamb con-
cluded his paper with a pertinent quotation from the address
which Stokes delivered at Cambridge in 1862, and which was
one of the shortest ever delivered ; —

" In this Section, more perhaps than in any other, we have
frequently to deal with subjects of a very abstract character,
which is many cases can be mastered only by patient study, at
leisure, of what has been written. The question may not un-
naturally be asked, If investigations of this kind can best be
followed l)y quiet study in one's own room, what is the use of
bringing them forward at a Sectional meeting at all ? I believe
that good may be done by public mention, in a meeting like
the present, of even somewhat abstract investigations; but
whether good is thus done, or the audience wearied to no pur-
pose, depends upon the judiciousness of the person by whom
the investigation is brought forward."

Sub-Section.

John KiAUT, K.C.I.K.,

Cosmic Physics.

Sir John I-Imot, K.C.I.K., M.A., F.R.S., was educated at

St. John's College, Cambridge.

i86g. — Bracketed Second Wrangler. First Smith's Prize-
man. Elected Fellow of St. John's College.

November. — Went out to India as Professor of Mathematics
in Engineering College, Koorkha.

Photo. I'll Hoiirlif <f- Shcitheril. |

SIR JOHN ELIOT.

1872. — Transferred to Muir College, Allhabad, also as Pro-
fessor of Mathematics.
1876. — Transferred to Calcutta as Professor of Physics, Pre-
sidency College, and Meteorological Reporter to the
Government of Bengal.
1886. — Appointed to officiate as Meteorological Reporter to
the Government of India, and in 1888 appointed
permanently.
i8gi. — Also appointed Director-General of Indian Obser-
vatories, when the Scientific Observatories at Bombay
(magnetic), Madras (astronomical), and Koodookund
(solar physics), were placed under the control of the
head of the Meteorological Department.
Has written numerous reports and meteorological
memoirs; also a "Handbook of Cyclonic Storms in the Bay
of Bengal." to serve as a practical book of reference to sailors
in that area.

Chief changes in India Meteorological Department during
his ri-^iiiu- : —

(i.) Large extension of storm warning and flood warning

work.
(2.) Large extension of area of meteorological observa-
tions, chiefly in India, Persia, and the Indian
Ocean.
(3.) Large extension of work of collection of meteoro-
logical data of the North Indian Ocean and Indian
area, and tabulation and publication of daily data
with chart.
(4.) Unification of the rainfall ; reporting systems and
publication of complete annual data for the Indian
Empire, &c., &c.
Also took a considerable share in the arrangements for the
establishment of a Solar Physics Observatory in India, and
for the commencement of a magnetic survey of India.

Sir John Eliot's address to the sub-section of Cosmical
Physics dealt chiefly with that department of meteorology which
has attracted most attention, and has held forth the greatest
possibilities of development daring recent years — the theory of
weather types. Sir John Eliot's duties as an official meteor-
ologist in India have enabled him to speak with the greatest
authority on this subject ; and his observations on the regularly
recurring weathertypes of the Indian Ocean are to be regarded
as the starting-point of these new methods of investigation. He
divided his theme at Cambridge into two parts — (i) A Brief
Sketch of the Broad Features of Tropical Meteorology in their
Relations to the General Meteorology of the Indo-Oceanic
Region; and (2) Illustrations of Abnormal Features of the
Meteorology of that Area for the Ten Years ending in igo2.
Following on the illustrations which he gave of the uses
of seasonal forecasting in India — uses which are identical,
in many instances, with the prosperity or the desolation
of millions of people — Sir John Eliot urged the establish-
ment of a system of Imperial meteorology. He would co-
ordinate the meteorological system of the British Empire, and
establish a central office for the investigation of problems of
Imperial meteorology. The area to be dealt with on the
ludo-Oceanic area was partially covered by a number of inde-
pendent meteorological systems, including those of Egypt,
East Africa, Central and South Ceylon, Mauritius, the Straits
Settlements, and Australia. Large areas were unrepresented,
and the departments controlling the systems w'orked indepen-
dently of each other. He suggested a combined system, of
which the following might be the leading principles : —

( 1 ) The extension of the field of observation by the establish-
ment of observatories in unrepresented areas, and the syste-
matic collection of marine meteorological data for the whole
area.

(2) The collection and tabulation of the data necessary to
give an adequate view of the larger abnormal features of the
meteorology of the whole area.

(3) The direction by some authoritative body of the
work of observation, collection, and tabulation of data, in
order to secure the use of similar methods for the thorough
discussion of the data.

(4) The preparation of the summaries of data required as
preliminary to the thorough scientific discussions, and for the
information of the officers controlling the work of observation
in the contriliutory areas. The earliest publication of the
data should be regarded as essential for use of oflices issuing
seasonal forecasts.

SlU'T., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

201

r scientific discussion of all the larger abnormal fea-
tures in any considerable part of the area and their correla-
tion to corrcspondini; or related variations in tlie remainder
of the area bv a central office furnished with an adeiniate
staft'.

(6) Possibly, suthcient authority on the part of tlie central
office to initiate special observations required for the elucida-
tion of special features for which there are no arrangements
in the general work of the various systems.

Section B. Chemistry.

Professor Sydney Young, D.Sc. F.R.S., is the third son of
Mr. Edward Young, of Liverpool, and was born on Decem-
ber 29 at Farnworth. near Widnes. He entered Owens
College in 1S76, becoming an .-Vssociato of the College in i.SSo,
and in the same year was awarded the Scholarship in Chemis-
try in the B.Sc. final of London L'niversity. He proceeded to
his D.Sc. degree three years later. At Owens College he

PROP. SYDNEY YOUNG.

conducted an investigation on " Alcoholic Thiorides," and at the
University of Strasburg. where he spent a year in Professor
Fittig's laboraton,', he carried out researches on " Ethyl-
valero-lactone " and other compounds. In 18S2 Dr. Young
was appointed Lecturer and Demonstrator of Chemistry in
University College, Bristol, and during the following five
years he was engaged in original work, chiefly in physical
chemistry, jointly with Professor Ramsay. On Professor
Ramsay's migration to London and occupation of the Pro-
fessorship of Chemistry at Gower Street, Dr. Young was
elected to the Chair of Chemistry at University College,
Bristol. He was elected a Fellow of the Royal Society in
1893, and is a Member of the Council of the London Physical
and Chemical Societies. He was appointed last October to
the Chair of Chemistry in Trinity College, Dublin, in succes-
sion to Professor Emerson Reynolds ; and this year, as an old
Associate of Owens College, Manchester, received the B.Sc.
degree of the new Victoria University. His important work
on " Fractional Distillation " was published last October.

Professor Sydney Young's Presidential address to the
Chemical Section was a review of the state of knowledge of
the chemical properties of mixtures, beginning with a summary
of Kopp's work during last century on the molecular volumes
and boiling points of chemical tompouuds and eudiug with the
researches of Professor Kuenen. Professor \oung defined the
investigations of the behaviour of liquids when mixed logctluT
as referring to ((() their miscibility, infinite, partial, or inajipre-
ciable; (/i) the relative volumes of the mixture and its com-
ponents; and (V) the heat evolved or absorbed ; .lud he uiMit
on to outline the modes of investigation appliiil to these
phenomena.

Section C. Geology. -Earth Scvilptvire.

Mu. AiBUKV Stkauan. F.K.S., M.A., F.G.S., District Guulo-
gist on the Geological Survey of England and Wales ; born
London, April 20, 1852. F.ducated at Eton and St. John's
College, Cambridge.

Pj/Zi/jfo/io/is.— Geological Survey. Memoirs on Chester,
Rhyl, Flint. Isle of Purlicck and Weymouth, South W.ilcs
Coalfield, and contributions to scientific journals.

AUBREY STRAHAN.

Mr. Aubrey Strahan's address to the Geological Section
was an attempt to outline the Earth Movements and Earth
Sculpture, gradual or cataclysmic, which resulted in the
geological formations and the external landscape of the
British Isles as now known. With such a history, he con-
cluded, and with the knowledge that mountain ranges had
been built in other parts of the world l)y upheavals of almost
recent date, thev had more cause to wonder that the internal
forces of the globe had left this region for so long, than reason
for believing that such phenomena had ceased. Slow changes
of level were still occurring; and these might be the outward
manifestation of more complicated movements in progress at
a depth. The President offered a conjecture as to what
appearance the globe would have presented had it not been
enveloped with an atmosphere and covered for the most part
with water. If these had not existed, the old scars, caused by
the belts of crushing and buckling, would have remained,
unsoftened by denudation, uncovered by sedimentation. The
Earth would then have appeared to the inhabitant of another

202

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

planet as enciMiip i^si d in a network of fine lines; and one
was prompted to ask whether our astronomers distiugnished
in any other planet markings attributable to this cause.

Section D.— Zoology.

William Batkson, M.A., F.R.S., Fellow of St. John's Col-
lege since 1.SS5. Born Whitby, 1.S61, son of l\ev. W. H. Bateson,
D.D., Master of St. John's Colle,.;e ; married Beatrice, daughter
of late Arthur Durham, Sjtiior Surgeon to Guy's Hospital
(1S96). Educated Rugby School and St. John's College, Cam-
bridge. Balfour Student iSSy-iSgo.

Pulilicatlons. — Materials for the Study of Variation, 1S94;
Mendel's Principles of Heredity, 1902.

Mr. William Bateson, F.K.S., took for his address to the
Section of Zoology a subject with which his name has long
beenconsp.cuously identified — " The Facts of Heredity and of
V'ariability of Species as Exhibited by the Practical Examina-
tion and Experiment of ' Breeding.' " The breeding pen was
to the zoologist, said Mr. Bateson, what the test tube was to
the chemist, and he insisted that the investigation of the
problems of heredity by experimental methods offered the sole
chance of progress with the problems of evolution. When
Darwin wrote his '• Origin of Species," that work which
crowned the great period in the study of the phenomena of
species, seemed to be, paradoxically enough, the signal
for a general halt. The treatise brought the origin of species
fairly within the grip of human iatelligence for the first time,
but, perhaps because it seemed to imply that the specific
differences in species were brought about only by the lapse of
immense periods of time, it turned men's thoughts to other
subjects that were more amenable to the limits of a human
life's investigation : and so the wide field from which Darwin
drew his store of facts had remained for some forty years un-
explored. Mr. Bateson went on to examine the corollaries to
the Darwinian hypothesis which other theories had con-
structed. Among them, for instance, was De Kries' theory of
mutations — by which species at a certain period in the long
history of their generations become imbued with a tendency
to change— and of greater importance to the student of
Iieredity were the laws due to the investigatory genius of
Mendel. The general conclusion to which investigation
appeared to point was th.at Nature exercised selective opera-
tions no less potent than those which man put into operation
in his experiments in breeding. In more scientific language,
the true corollary to \'irchow's aphorism that every living cell
sprang from a living cell, was that " Every variation froiu type
is founded on a patliological accident." In conclusion the
President stated the limitations of the knowledge of heredity.
'■ There are others who look to the science of heredity with a
lofiier aspiration ; who ask. Can any of this be used to help
those who come after to be better than we are— healthier,
wiser, or more worthy ? The answer to this cpiestion is \o.
almost without qualification. We have no experience of any
means by which transmission may be made to deviate from its
course; nor from the moment of fertilisation can teaching, or
hygiene, or exhortation pick out the particles of evil in that
zygote, or put in one particle of good. Education, sanita-
tion, and the rest, are but the giving or withholding of oppor-
tunity."

Section E.— Geography.— Mankind and
Mountains.

Mi;. Doll}]. as Fklshfili.i., F.K.(,.S.. has supplied us with the
following particulars: Born 1S45. Travelled first in Alps 1S54;
was constantly taken there liy parents and imbibed tastes for
mountains early; climbed Mont Blanc iS6j, made long journey
including inany - new " peaks and passes in 1864, recorded in
" Thoiion t Trent," privately printed journal, now rare. Visited
Caucasus after journey in Svria in 1S68 (described in " Travels
into Central Caucasus and Hashaii ") ; ascended for fir.st time
Elboug and Kasbeh, returned to Caucasus in 18S7 and 1889,
ascending Tetwald .and other peaks; crossed Caucasus eleven
times by eight different passes— see '• The Exploration of the
Caucasus," a luxurious book illustrated by Vittorio Sells;
visited Sikkim in 1899 and made first tour of Kawgchcnjung.i
penetrating Nepaulcso valleys and crossing a pass of over
20,000 feet after the heaviest snowlall ever known in that
region (see " Round Kawgcheujuuga "). My Alpine tours are

recorded in "The Italian Alps," 1S75. I was for some years, in
succession to Sir Leslie Stephen, editor of the Alpine Journal ;
have been President of the .Alpine Club ; was for thirteen years
an Hon. Secretary of the Royal Geographical Society, and am
now Chairman of Committee of the Society of Authors, Presi-
dent of the Society of Geographical Teachers, and Treasurer
of the Hellenic S )ciety. I edited two editions of the Royal
Geographical Society's " Hints to Travellers " and also two
editions of " Murray's Handbook to Switzerland," and have
contributed to the Badminton Library and various periodicals.
I know, besides, the .'Vlps, Norway, Italy, Corsica, Algeria,
Spain ; travelled in Greece this spring and climbed Taggetus
and Parnassus.

My father was one of the solicitors to the Bank of England.
I am a landowner in Susse.x. I had a large share in remodell-
ing the publications of ths R 5yal Geographical Society, and
have worked for the improvement of in ips, ordnance and
private, in this country.

Have written articles on historical subjects connected with
mountains, " Pass of Hannibal " ; and physical, " The Con-
servative .Action of Ice." I received in 1S93 one of the gold
medals of the Royal Geographical Society and a gold medal
at the Paris Exhibition, 1900, for my " Exploration of the
Caucasus."

Mr. Douglas Freshfield's address to the Geological Section,
" Mankind and Mountains," was highly historical in its survey
of the place which mountains occupy in Nature, and their
influence, both spiritual and material, on mankind ; but it
raised several points of topical interest, including the topo-
graphy and physical peculiarities of the Himalayas; the
period of shrinking and advance of the Swiss glaciers with
their hypothecated reference to sun-spot periods; and the
question of the influence of mountain heights on respir.atioii
and physical endurance. The President remarked that the
advance to Lhasa ought to throw much light on this subject.
The experience of most mountaineers in the last few years
had tended to modify the belief that bodily weakness increased
more or less regularly with increasing altitude. Mr. White,
the Resident in Sikkim, and Mr. Freshfield himself both found
on the borders of Tibet that the feelings of discomfort and
fatigue which manifested themselves at about 14,600 to 16,000
feet tended to diminish as they climbed to 20,000 or
21,000 feet.

Section F.— Economic Science and
Statistics. Hovising the Poor.

Professor William Smart, LL.D., has been kind enough to
supply us with the following biographical particulars which he
very modestly, but quite wTongly, supposes are "not of much
interest."

'■ When a student I broke down through overwork ; and,
giving up all hope of a professional career, catered my father's
business, where I remained for .some 15 years, going through
all the stages, from office boy to commercial partner. My
firm was one of the Clark's, now incorporated with the great
thread 'combine' of J. & P. Coats. The factories were in
Glasgow and New Jersev, and so I obtained that knowledge of
practical manufacturing under Free Trade and under pro-
tective conditions which, as one may imagine, has done me
some little service in my last book, Tlic Rtturn to Protection.

"It was at my initiative that the Glasgow Municipal Commis-
sion on the Housing of the Poor was constituted two years
ago, and my presidential address reflects the experience gained
thereat.

" I need only add, I think, that the Adam Smith Chair in the
University of Glasgow was founded in 1896, and that I am the
first occupant of it. I am a Doctor of Philosophy of Glasgow
and an LL.D. of St. .Andrews."

Professor Smart, addressed the Section on some of the
problems of housing the poor, on which, as a member of the
Glasgow Municipal Commission, he had been engaged in
examining during the last two years. That Commission
arose out of the necessity which had presented itself, con-
tingent on the extensive demolition of insanitary and unsuit-
able dwellings in Glasgow, of housing the poor whom the
extensive municipal operations were turning out. It incpiired
into the causes of o\ercrowding ; the remedies to be adopted
in curing and preventing overcrowding ; and the important

KNOWLEDGE ct SCIENTIFIC NEWS.

203

problem of the extent to which the municipality was justified
in itself building and owning houses for certain of the poorer
classes. Professor Smart's address considered mainly tlic
building and owning of houses as a branch of municipal
activity, and examined the particular circiimstancos which

Photo, bij T. it R. Annan, d- .Sun..]

PROF. WILLIAM SMART.

might suggest a revision or relaxation of existing principles.
Taking the question of principles first, he pointed out that for
a municipality to add a new competitive industry to its activi-
ties was a serious matter from three points of view. In the
first place, house-owning was a business of a special kind and
one in which success was not certain. In the second place
the municipalit\' entered into direct competition with its own
ratepayers, and that in a way quite distinct from the case in
which a municipality might provide all the water, gas, elec-
tricity, or tramway service which its citizens might demand.
In the third place, the municipality, by pledging the public
credit for a new debt, was probably preventing, immediately,
or in the future, the expansion of municipal activity in other
directions. These considerations were not decisive against
municipal housing, which in some respects was as necessary
for the protection and encouragement of the community as the
provision of gas or water. For example, a sanitary and com-
fortable house among quiet neighbours was a direct condition
of the efficiency of labour and was quite definitely one of the
factors of wage-earning. In other words, a good house, as
compared with lodging in a slum, brought with it the possi-
bility of paying for it. The point which especially suggested
municipal house-owning was that municipal control over
certain classes of houses was necessary in wage-earners'
interests. But while the attractiveness of a clean city, to
be by these means secured, was one thing, the attrac-
tiveness of low rents, which to the poor man's mind was
an equally large consideration, was quite another. Was a
municipality, in its desire to provide a clean city, to provide
also low rents at the expense of the general ratepayer ? Pro-
fessor Smart drew attention at this point to the two proposi-
tions usually made on this head : the first, that there was a
class which could not afford to pay the higher rent ; and the
second, that that was a valid reason for the municipality

providing them with a lower one. With regard to some people
alleged to be unable to pay the higher rent, he ;igain urged
that the improvement in their surroundings would make them
better wage-earners; with regmd to other people, to whom
this view could not be held to apply, .1 municipality which
propped them up by giving them lodgings at less than the
market rate was supporting the employer in lowering the
mininuim wage, and was aiding in tlic undesirable object of
attracting more and more unskilled labour, and hopeless,
helpless people into tlie towns. These, then, were ihe general
arguments against nnmicipal building on a large se.ile, or, as
one might say, "on principle." There remained the s])cci;d
circumstances in which a Cnrpnralion like (Glasgow was
justified in building municipal dwelling-houses or lodgiri^-'
houses. The first case was that in which the Corpor;ition, in
order to benefit the city as a whole, was pulling down ins.ini-
tary or crowded areas, and dispossessing working pcojjle r>f
their homes; and the second case was that in which, in order
to fulfil modern hygienic rcquiremt nts, a kind of house was
being made necessary by municipal regulations, which could
not be let at the old and cheaper rents. The chief tiling that
;i numicipality had now to do was to see that the old prob-
lems of insanitary and overcrowded houses, whicli its own
in.action had allowed to come into exisleiiee, should not
recin\

Section G.— Engineering. — Discovery and
Invention.

Thk Hon. Chakles Parsons, D.Sc, F.R.S., fourtli son of
the third Earl of Rosse. Educated — PrivateTuilion, St. John's
College, Cambridge. Scholar, 187^. Eleventh Wr.ingler,
1876. Elected E.R.S., 189S. Rowed "in L.U.B.C ist Boat and

hii liiliot d- Fri/.l

THE HON. CHARLES PARSONS.

won the College Pairs, 1876. Is proprietor of the engineering
works, C. A. Parsons and Co., and Managing Director of the
Parsons Marine Steam Turbine Company. He has developed
the steam turbine and made it suitable for the generation of
electricity and the propulsion of war and mercantile vessels.

--^

204

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

In addressing the lingineering Section on the subject of
'_' Invention," the Hon. Charles Parsons considered the subject
inits evolutionary aspect, not as a phenomenon suddenly
arising out of some happy strol<e of fortune, but as the con-
sunmiation of the successive laljours of a number of workers.
From this point of view invention was discovery phis develop-
ment. Generally what was usually called an invention was
the work of many individuals, each one adding something to
the work of his predecessors, each one suggesting something to
overcome some difficulty, trying many things, testing them
when possible, rejecting the failures, retaining the best, and
by a process of gradual selection arriving at the best metliod
of accomplishing the end in \iew. For example, the first true
internal-combustion engine was the cannon. In 1(180 Hug-
gens, and ten years later Papin, tried to use gunpowder as a
means of obtaining power by exploding it in a large vessel with
escape valves. That was a mistake due to ignorance of
thermo-djnamic laws, which would have taught them that the
best results would be obtained by exploding under pressure.
A century later Street tried to use the vapour of turpentine as
an explosive mixture, but his machine failed from bad con-
struction, and Brown, a generation after that, tried Hnggens'
residual vacuum method and failed. Then came Wright in
1833 with a good gas engine, Barnett — who improved on this
design — Bansanti, and Matencci each adding something or
subtracting something, till Lenoir in 1866 made the first real
.•md practicable engine. F"rom the consideration of the inven-
tion the President passed on to the inventor, his difficulties and
the obstacles placed in his way by patent laws, and the small
reward for his services compared with the benefits he con-
ferred on his fellows. In the course of his address, the Pre-
sident mentioned two inventions, the undertaking of which
would be of great service to mankind, but the practical rewards
of which to the individual inventor were so small and so diffi-
cult to secure adequately to him that they could hardly be
undertaken by private eft'ort. One was the problem of aerial
navigation, which could only be successfullv solved by an
organised and adequately trained body of engineers, and the
expenditure of a large sum of money. ' The other was the ex-
ploration of the lower depths of the earth — the deepest borings
or shafts in which were at present little more than a mile. The
President described a hypothetical method of sinking ashaftto
great depths, and offered an interesting estimate of the cost.
For £500,000 a shaft two miles in depth could be sunk in ten
ye.ars ; for ;f 1,100,000 a shaft of four miles could be sunk in
twenty-five years; and so on. A shaft twelve miles in depth
could be sunk in 85 years, and would cost £5,000,000. The
temperature of the rock at that depth would be, he estimated,
2y2 degrees Centigrade.

Section H,— Anthropology,— The Pitt

R-ivers Collection.

Mr. Hhnrv Balfour, M.A., was born in 1863. Educated at
Charterhouse School. Entered Oxford University in 1881 as a
commoner of Trinity College. After taking degree in the
Honour School of Comparative Anatomy, acted under Pro-
fessor H. N. Moseley as Assistant Curator of the Pitt Rivers
Ethnological Collection (presented to the University in 1884).
After Professor Moseley's death, became Curator of the Pitt
Rivers Museum, which had developed considerably. Elected a
member of the Council of the Anthropological Institute of
Great Britain in i8gi, and its President in 1903 and again in
ig04. Elected in 1903 to a Research Fellowship at Exeter
College, Oxford. Corresponding member of the Anthropo-
logical Societies of Paris, Rome and Florence. President of
the Oxford Fencing Club.

The address of Mr. Henry Balfour to the Anthropological
Section was in the main a description of the ethnographical
collection of Colonel Lane Fox. which is better known as the
Pitt Rivers collection, from the name which Colonel Lane
Fox took in 1880. The President's avowed object in consider-
ing this subject was first to bear witness to the very great
importance of General Pitt Rivers' contribution to the
scientific study of mankind in general ; and to defend the
system of arrangement which has been adopted in respect of
his ethnographical collection. Its collector based his first
in()uiries on the theory that the weapons which man used were

Photo, hn Hitls ,f- Saunrlers.j

HENRY BALFOUR.

built up by a process of evolution ; and he was led to believe
that the same principles must probably govern the develop-
ment of the other arts, appliances, and ideas of mankind. On
this belief and principle his collection was formed.

Section I.— Physiology.— Correlation of
Nerve = Arcs.

Professor Sherrington, M.D. and D.Sc, Cambridge;
LL.D. Toronto; made Fellow of Royal Society in 1893 ; and
Honorary Member of the Academy of Medicine in Vienna.
Has been given the Marshall Hall Prize and the Baily Medal-
His chief work has been on the nervous system. Eight years
Lecturer on Physiology at St. Thomas's Hospital, London,
and four years Professor Superintendent of the Brown Insti-
tute, London.

Professor C. S. Sherrington began his address to the Phy-
siological Section with a definition of the points of view from
which physiology studies the nervous system. They were
three. One of them regarded its processes of nutrition. Such
processes could be followed in the nerve cell, as in other cells.
But the cells of the nervous system had certain functions which
were specialised ; and one of these was the power of the ner-
vous cell to transmit states of excitement — a power which was
called conductivity. The examination of this property was
the second problem. The third was the investigation of the
way in which by this conductivity the separate cells and units
of an animal body were welded into a single whole, and how
from a mere collection of organs there was made a single
animal. It was one of the general problems of this third
branch of inquiry to which Professor Sherrington invited the
attention of his hearers ; and the problem was concerned witli
the chain of conduction, and with the ways in which the nerve
arcs, from a sense organ to a limb muscle, for example, are
connected.

Sept., 1904.]

KNOWLEDGE c^ SCIENTIFIC NEWS.

205

Photo, bjf Soper & SUdmnn.]

PROF. C. S. SHERRINGTON.

Section K. Bota.ny.— The Preception of
the Force of Gravity by Plants.

Mr. Francis Darwin, I'.K.S., President of Uh- Botanical
Section, is the third son of Charles Darwin and of Emma
Wedgwood, and was born 184S, at Down. (The Editors of
" Knowledge and Scientific News "asked Mr. Darwin if he
would be kind enough to oblige them with some biographical par-
ticulars, and those that he has furnished are so interesting
that it is thought desirable to leave them in their present
form.) Mr. Darwin writes: — "I was educated at Trinity
College, Cambridge (M.A., M.B.), and St. George's Hospital.
London. When a medical student I worked at the Brown
Institute under Dr. E. Klein, and this was my first real bit of
education in science. Dr. Klein gave me some original work
to do, part of which served as my thesis for the Cambridge
M.B. Dr. Klein's influence made me desire to take up natural
science rather than the practice of medicine, so that I was
only too glad to accept my father's proposition, that I should
act as his assistant. I lived at Down, working with my father
till his death in 1882. I then moved to Cambridge where I
ultimately became Reader in Botany and Fellow of Christ's,
my father's ol<l college.

" My scientific work has been in Physiological Botany, on
which I have published various papers. My ' Practical
Physiology of Plants' (1894) (for which the late E. H. Acton
wrote the chemical part) has had some influence on the teach-
ing of this part of botany, and is now in its 3rd edition. I
also wrote a little book, ' The Elements of Botany' (1895),
which gives the substance of my lectures to medical students.

" In 1887 I brought out 'The Life and Letters of Charles
Darwin.' In 1892 an abbreviated version in one volume was
published, giving the autol)iography, my personal recollec-
tions, and a selection of the letters.

" In 1903, in collaboration with Mr. Seward, I brought out
' More Letters of Charles Darwin,' two volumes made up
chiefly of letters which could not be included in the ' Life,'
but also containing materi.il obtained since 1887. During the
present summer I shall lesign the Readership of Botany and
my Fellowship, and propose to live in London.

"Through the kindness of the Committee of the Chelsea
Physic Garden, I am for the present pnn idcd with a labora-
tory, and with house room for my fatlier's library, which I
have been permitted to deposit in the lecluro-room at the
Physic Garden."

Mr. Francis Darwin's address to the Botanical Section
was a summary of the knowledge that has been gained of the
ways in which plants become sensible of the influence ot
gravity, and .adjust themselves to its suggestions. As long ago
as 1824 Dutrochct imagined that tlie movements of plants-
were dictated at the suggestion of changes in their siir
roir- ''■ •■■it'-r-r th:iii thit tlic,- v.rrn thr ilircct ;ind nrcos?arv

Photo, by KUiot {■• Fnj

FRANCIS DARWIN.

result of such changes. Mr. Darwin has been in the habit of
expressing the same thing in other words, using the idea of a
guide or sign-posts, by the perception of which plants were
able to make their way successfully through the difficulties of
their surroundings. The force of gravity was one of the most
striking features of a plant's environment ; and in the sensi-
tiveness of a plant to this force we had one of the most wide-
spread instances of a plant's ability to read a signpost and
direct its growth accordingly. Mr. Darwin's paper reviewed
the ways in which what might be called the sense-organs
of plants transmit the knowledge throughout its organism,
and the ways by which in theory these sense organs are
affected by the outside influence.

Sub= Section. —Agriculture.

Dr. William Somervklle, M..A.., D.Sc, owned and fanned a
small estate in Lanarkshire till 24. From 24 to 28 studied agri-
cultural science in Edinburgh University during winter, and
travelled on the Continent during summer. Secured Vans
Dunlop Scholarship and went to Munich in iS«8 to study
forestry. Appointed Lecturer on Forestry, F.diiiburgh Uni-
versity, 1S89. Professor of .'\griculture and Forestry, Durham
College of Science, 1891. Professor of Agriculture, Camljridge,
and Professorial Fellow of King's College, 1899. Assistant
Secretary to the Board of Agriculture, with charge of the
Branches of Intelligence and Education, 1902. Started experi-

206

KNOWLEDGE & SCIENTIFIC NEWS.

'Sept., 1904.

meota farms in Northumberland and Cambridge. Chiefly
identified with experimental work on finger, and, toe in
turnips, and with the influence of manures on the feeding
properties of pasture. Graduate of Edinburgh, Munich, Dur-
ham, and Cambridge. Has served on Departmental Com-
mittees on Forestry, Sheep Parasites, and Fruit. Written a
good deal on agricultural and forestal matters.

Dr. William Somerville. the President of the new Sub-
Section of Agriculture, took for his subject "Recent Work ii'
.•\gricultural Science " ; and dealt successively with the latest
experiments at Rothamsted : German work on the storage cf
farmyard manure, forestry, the Woburn Fruit Station, and
the improvements in the scientific variation of crops. Dr.
Somervelle also devoted son:e paragraphs to that fixation by
electricit)' of atmospheric nitrogen, which, as Sir William
Crookes hoped, might some daj- provide us with artificial
nitrates and cheaper manures and soil stinuilants. This work
was going en well, said the President, and he believed agricul-
ture would not have long to wait before it was placed in

attempt to define the limits of investigation which science
might usefully set itself in dealing with education. In the con-
sideration of these limits it was necessary to give due regard
to right ideals of moral and social progress as a primary part
of the whole ; and it was necessary to decide what methods of
investigation were appropriate and what were inappropriate
to the duty of education. The Bishop of Hereford went on to

Pholo. hy MojTal.]

DR. WILLIAM SOMERVILLE.

PUoto. btj IT. H. Btt.-lii,.
THE RIGHT REV.

THE LORD BISHOP OF HEREFORD.

possession of " that most powerful agent of production." The
President also reviewed the partial failure of the attempt to
supply artificially the bacterial organisms which are naturallv
found at the nodules of leguminous plants, and so stimulate
their growth. These bacterial cultures — "nitragin," as the
experimental samples were called — had been a failure of late
when applied on a large scale ; but both in Germany and the
United States, where faith and belief in the value of
"nitragin" was considerable, the experiments were being
vigorously pursued with what was called " improved nitragin."

Section L.— Educational Science.

The Rt. Rev. John Percival, D.D., Bishop of Hereford.
Born 1S34, son of William Percival. Brough, Sowerby, West-
moreland, and Jane, daughter of William Longmire, Bolton,
Westmoreland. Married first, 1S62, Louisa, daughter of James
Holland (died 1S96), and second, 1S99, Mar)' Georgina,
daughter of the late Frederick Symonds, F.C.S., Oxford.
Educated at the Grammar School. Appleby, Westmoreland,
and Oueen's College, Oxford, of which he was a Scholar.
Junior Mathematical University Scholar 1S55, Double First
Mods and Finals ; M..A., i,S6i. Fellow of Oueen's College,
Oxford. Ordained, 1S60. .Assistant Master^Rugbv. Head-
master Clifton College, 1S62-1S7S. Prebendary of Exeter,
1S71-S2. Canonof Bristol, 1SS2-7. President Trinity College,
Oxford, 1878-S7. Headmaster Rugby. 1SS7-1S95. Bishop of
Hereford since 1S95.
The Presidential address to the Educational Section was an

criticise the various defects in the national outlook on educa-
tion : and in the various systems of primar\% secondary, and
public school education ; and he laid down the general
principle that one of the things needed for the general improve-
ment of our secondary education was that every private
school, of whatever kind, should be liable to public inspection
and public report thereon : that a licence should be required
for every such school : and that the staff and their qualifica-
tions, and the remuneration given to each of them, the sanitary
condition, suitability and educational equipment of the pre-
mises, should all be considered in connection with the giving
or withholding of a licence.

THE FOREIGN GUESTS.

Upwards of 200 American. Canadian, and foreign men of
science attended the Cambridge gathering of the .Association.
We append a few details respecting the scientific achieve-
ments of some of the more familiar names. !imit;itions of space
forbidding extended reference.

AincyictDt and Canadian. — Professor W. O. Atwater, who
lectured in the physiological section on " Nutrition Experi-
ments on Man in the United States," has occupied the chair
of Chemistrj' in the Wesleyan University, Middletown, since
1873. On the establishment of the Connecticut .Agricultural

Sept., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

207

Experiment Station — the first of its kind in the United States
— he became Director, and engas^ed in the important nutrition
investigations promoted l>y Congress in connection with the
Experiment Stations of the United States Agricultural Depart-
ment. The Carnegie Institution has granted £1000 in further-
ance of this work, and £1300 to Dr. .Arthur tjamgee, I'.K.S.,
of Moutrenx. for the preparation of a report upon the results
so fai' attained. Professor .-Vtwater has published numerous
papers in physiologj'.

Prof. W". B. Scott, of Princeton University, New Jersey,
is best known for his labours in the elucidation of the fauna
of Santa Cruz; also for investigations connected with the
Prmceton Expedition to Patagonia. The results of the latter
will be completed during the next few years in eight
volumes, somewhat after the model of the '• Challenger "
series of zoological reports. Mr. J. Pierpont Morgan has
given a subsidy towards the issue. The first instalment,
under the editorship of Professor Scott, bears ample testimony
to the importance of the researches, while being highly
creditable to American zoological workers.

Prof. A. B. M.\c.\lllm, who holds the Chair of Physiology
in the University of Toronto, is well-known for his researches
in histology and physiology ; and is a teacher of repute. He
took a prominent part in the founding of the Canadian
Marine Biological Station at St. Andrews, North I^runswick,
as well as that at Canso, Nova Scotia. He is the author ot
many papers, including, " On the Distribution of Iron in Ani-
mal and Plant Cells" (Brit. Assoc. 1S1J7) ; and "On the
Localisation of Potassium in Animal and Plant Cells" (Brit.
Assoc. 1903).

Prof. A. Lawrencic Kotch, a distinguished meti-orologist,
is Director of the Blue Hill Observatory, U.S.A., librarian of
the American Academy of Sciences, and a Chevalier of the
Legion of Honour. His observatory was established in 1885,
and from thence have been issued from time to time the
results of novel investigations of the upper air. He was the
first to obtain accurate meteorological records over the
Atlantic by means of cloud observations and self-recording
instruments lifted by kites.

Prof. John DEwtv is Director of the School of Educa-
tion and Professor of Philosophy in the University of Chicago.
He held formerly similar positions in the Universities of
Michigan and Minnesota. Professor Dewey is an authority
upon ihe p.sychology of numbers, and author of a work on the
Theory ol Ethics.

Prof. K. W. Wood, of the Physical Department ol the
University of Wisconsin, who belongs to the younger school
of American physicists, is well known in English scientific
circles. In igoo, he read a paper at the Royal Society on
the '• Photography of Sound Waves," and at the Society of
Arts on the " Diffraction Process of Colour Photography."
He is possessed of striking experimental originality, which
gives him such a mastery over simple forms of apparatus as
to make those accustomed to work only through the medium
of more elaborate means somewhat envious of his laboratory
and teaching methods. On the occasion of one of his summer
visits to San Erancisco, struck with the beautiful miniature
mirages to be seen during sunhght on certain of the flagstoned
sidewalks, he set himself with success to secure a photograph
of the phenomenon. At the recent meeting Professor Wood
contributed a paper on "Colour Photography."

Prof. Ka.ms.\y Wright, Vice-President of Toronto Univer-
sity, is also Curator of the Biological Museum and Professor of
Biology in the University. His writings upon the comparative
anatomy of vertebrates are numerous, fie has prepared a
special report upon the Fish and Fisheries of Ontario.

Foreign. — M. VvES Guyot was formerly Minister of Public
Works in Paris. The publications of the Cobden Club, of
which he is an honorary member, have made his writings on
economic subjects, and particularly on the tenets of Free
Trade, familiar in this country. .\1. Guyot was recently the
recipient of the " Guy " Medal of the Royal Statistical Society
for his paper, " The Sugar Industry on the Continent."

Dr. Josef Korosi, Director of the Bureau of Municipal Statis-
tics at Budapest, is a distinguished member of the Hungarian
Academy of Sciences. Under his supervision valuable reports
are i=sucd from li.ne to time dealing with mortality and other

branches of the science of Demography or Vital Statistics. A
voluminous paper on "N.ilality" was coininiinicated per-
sonally by him to llie Royal Society in i8y.;, and afterwards
published in the I'liilosophical 'Jrcinsitiiidiis.

Dk. Paul Guoth is Professor of Mineralogy and t'ryslal-
lography in the University of Munich, and Keeper ot the
Collection of Minerals. His studies have earned for him a
European reputation. In 1877 he established the ZcUschrift
fiir Kiystiilloi^i-tiphic- und Mincralofiic, and in 190.;, to mark the
^5lh year of issue of the journal under liis (;ditorship, an
linglish Conuiiittce of Mineralogists, (ieologists, and others
presented the Professor with his portr.ait, painted by Griilzner,
of Munich. On the occasion of his visit here, the University
of Cambridge conferred on him tlu^ degree of Doctor of
Science.

Dk. A. SoMMEKFKLD is Profcssor of Mechanics in the Royal
Technical School, Aachen, Prussia. In a paper on the
" Scientific Results and Aims of Modern Ap[)lied Mechanics,"
lately published, he has emphasised the desirability of a more
practical application of the principles of mechanics from the
teaching standpoint.

Pkof. Oscak Mo.ntki.ius of the State Museum of History
and of Numismatics, Stockholm, is eminent for his researches
upon the ancient civilisation .and antitiuities of Sweden and
other Scandinavian countries. It may \n: mentioned that the
subject of his contribution at Cambridge- namely, the evolu-
tion of the lotus-ornament — had already received attention at
the hands of Mr. W. H. Goodyear in the Amcruan Juurmil
of Archicoloi;y, iSyi, in his paper, " The Giainmar of the
Lotus." The results of Professor Montelius' study will be
awaited with interest.

M. Hi:;>ui BEcyUEKEL, Professor of Physics in the Hcole
Polytechnicpie, Paris, has a world-wide reputation on account
of his epoch-making experiments with the mineral uranium,
whence has sprung the new knowledge, " radio-activity."
In i8g6 he discovered that salts of uranium emitted a radia-
tion which was capable of affecting a photographic plate after
traversing thin metallic screens ; also that the rays possessed
the power of making gas through which they passed a
conductor of electricity. Many will recall Professor J. J.
Thomson's evening lecture at the British Association meeting
of igo2, " Becquerel Rays and Radio-Activity." Professor
Becquerel comes of a line of distinguished physicists. His
grandfather and father were both foreign Members of the
Royal Society, the former a Copley Medallist of that body ;
while the Professor himself has received its Riimford Medal.
He was awarded the great Physics prize of the Nobel Institute
last year, conjointly with M. and Mine. Curie.

Dr. Ekich von Duvgalski, Professor of Geography in the
University of Berhn, was Scientific Director of the recent
German Antarctic Expedition in the Gnu\s, which sailed early
in igo2, and returned last year after accomplishing much
successful work. Dr. von Drygalski read a paper dealing with
the results of the Expedition before the Geographical Section
of the Association.

Du. R. LivY, ot the Italian Ministry of War, Rome, is a
distinguished anthropologist. His attendance at Cambridge
was specially sought in ortler that his experience in methods
of anthropometry might be available in discussions in Section
H. on the advantage of a British anthropometric survey. Dr.
Livy has recently embodied the results of anthropometric
investigations among the troops of the Italian Army in the
work, "Anthropometric Milit.iires."

Comparative Legislation.— Included in the second part of
Vol. V. of the "Journal of Comparative Legislation" (John
Murray) are articles on Englisli and Continental inilitary
cjdes, by J. E. K. Stephens; " Obeah " in Jamaica, by S.
Leslie Thornton ; International Railway Transport, by G. C.
Pnillimore; and contributions concerning the Antwerp Con-
ference, by Mr. Justice Kennedy and T. G. Cower, K.C. ; and
on a Council of the Empire by the Hon. W. P. Reeves and
Professor T. E. Holland, K.C. Sir John .M.acdoiiell writes on
Contracts for Labour, and the Lite Sir William Rattigan on
the great jurist Bartolus. The volume is prelaced by a portrait
and a biogiap.iical no. ice of the Rt. Hon. R. B. Ilaldane.

2o8

KNOWLEDGE & SCIENTIFIC NEWS.

[Sspt., 1904.

Terrifying Ma^sks acrvd
WoLrnirvg Liveries.

By rEKcv Collins.

It has been suggested — and the theory lias received, to
some extent, the support of experimental proof — that cer-
tain kinds of insects derive protection from the grotesque-
ness or hideousness of their appearance. An oft-cited
example is the very remarkable-looking caterpillar of
Stauvopus fani, the lobster moth. This insect was at one
time considered a great rarity in England, and as such
was much prized by collectors. Of recent years, how-
ever, it has been found in considerable numbers in the
beech woods of the Upper Thames valley, and entomolo-
gists have had ample opportunity to examine its appear-
ance and habits in the wild state.

Professor Poulton describes the resting caterpillar as
possessing a considerable resemblance to a withered leaf
irregularly curled up — the likeness being gained by the
combined effect of the creature's colour, its curiously
modified legs, and the manner in which these are
arranged.

It is clear, therefore, that this remarkable larva is con-

Larva of Vh,uro,;,miin I'ornllus, in terrifying attitude (drawn from lifel.

cealed from its enemies by a protective likeness to its
habitual surroundings. But it has yet another means of
defence at its disposal. Should it be disturbed by a rust-
ling of the leaves and twigs in its immediate neighbour-
hood, and become convinced that its disguise has been
penetrated, it immediately assumes what has been called
its " terrifying attitude."

In this position it is described as looking very like a
large spider, but with all the characteristic points in a
spider's appearance greatly exaggerated for the sake of
effect. The legs and body are, for the time being,
arranged in such a manner that the creature seems
changed from a harmless caterpillar into something
strangely disquieting to look upon.

In thus mimicking the attitude and appearance of an
exaggerated spider, the lobster moth caterpillar is really
trading upon the reputation of a well-recognised noxious
creature ; and the defence has been shown by experiment
to be of no little avail against the attacks of birds and
other insect-eating creatures, which exhibit varying
degrees ofalarm and disgust at sight of the caterpillar in its
terrifying attitude. But, as several observers have pointed
out, it is more than likely that the spider-like appear-
ance exists mainly as a special safeguard against the insect
enemies of Staiiivpiis fagi. In conmion with the larvx of
tnost Lepidopterous insects, this caterpillar is liable to

the attacks of ichneumon flies, which deposit their eggs
upon or beneath its skin. In the majority of instances such
" stung " larv.-E die miserably ere they are able to assume
the imago state ; and it is only reasonable to assume that
any trick or device calculated to scare away these insect
foes would directly benefit the species by enabling a

Larva of Chat'iucawpa (//lein'r, showing "eye spots" on fourth and fifth
segments of body.

greater number of its caterpillars to arrive at maturity.
And as a large and presumaijly ferocious spider is a vision
of dread to all the lesser denizens of the insect world, the
lobster moth caterpillar's terrifying mask is probably very
effective.

Aldus sp. Central America. As it appears when running; and v\hen,

under the stimulus of alarm, it has drawn its legs and

antenna; beneath its body.

Similar instances of what looks like trading upon the
reputation of some well-known noxious creature occur
among insects, and in some instances the prototype
ieems to belong to some widely difl^erent group of living
creatures. Thus, a South American caterpillar mentioned
by Mr. Bates startled everyone to whom it was shown

Sept., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

jog

by its snake-like appearance ; while amons our native
species the larva^ of the two elephant hawk moths
(Chiuroiampa elpenor and C. (■orcdlns) are striking; instances
of a protection gained in a similar manner.

Like the caterpillars of the lobster moth, those of the
elephant hawks are ditlicult to detect when they are at

Larvie of Euchdia jnrnbtftr.

home among the leaves of their food plants, owing to
their brown — or more rarely green — colouring. But
when actually discovered, or when thoroughly alarmed
by the rustling of the leaves, the caterpillar draws back
its head and the first three segments of its body into the
fourth and fifth segments. What then happens is well

iletfwma themUto. Ex Rio Granda iblack, with "clear" areasi.

described by Professor Poulton. " These two rings (the
fourth and fifth segments) are thus swollen, and look
like the head of an animal upon which four enormous,
terrible-looking eyes are prominent. The effect is greatly
heightened by the suddenness of the transformation,
which endows an innocent-looking animal with a terrify-
ing and serpent-like appearance."

This description applies to the C. dpcnor. In the case
of C. poncUus the eye spots on the fifth segment, though
present, are comparatively inconspicuous. It is a curious
fact that these strange markings do not attract particular
attention when the caterpillars are quietly at rest or feed-
ing. As soon, however, as they asstune their terrifying
mask, under the stimulus of apprehended danger, the
staring " eyes " — owing to the swelling of the segments
as the head and first three body rings are withdrawn —
become enormous and prominent. All field entomologists
who are familiar with tiiese caterpillars in the wild state
are willing to bear testimony to their startling appear-
ance when they have assumed their terrifying attitude.

\"ery similar eye spots, probably of a like protective
value, are seen upon the thoraces of certain Central
American beetles of the genus Alans. As in this case the
markings are delineated upon the hard surface of the
thorax they are not really more marked at one time than
another. Yet their terrifying apjpearance is enhanced
considerably when the beetle assumes the attitude with
which it responds to indications of approaching danger.
In common with most species of the great " click-beetle"
group ( FJateridcrj to which the genus Alans belongs, these
insects are capable of folding their legs and antenna' so

Meliitva m^'satis.

Ex Columbia. S. A. ired, brown; anterior area « of fore-
wings black, spotted whiter.

closely beneath the body that they are completely hidden,
and of remaining perfectly (juiescent in this attitude for a
long period of tune. A glance at the accompanying
photograph will give the reader some idea of the weird
appearance of an Alnus beetle under these conditions.
It cannot be said to resemble any other living creature,
noxious or innoxious. Yet its appearance is sufficiently
forbidding to discourage hostile attack.

In dealing with the first part of our title we have
briefly discussed several insects which are able, at will,
to masquerade as something terrible and alarming. They
can put on, as it were, terrifying masks, and scare away
their would-be persecutors. Bui the protection thus
gained is the outcome of bare-faced bluff, and it is con-
ceivable that the enemy may one day discover and profit
by this fact. Warning liveries, on the other hand, are
anything but meaningless bluster. They indicate that
the creatures distinguished by them possess certain
noxious characteristics which render them unwholesome
or unpalatable.

At the present day, students of entomology accord a
fairly general acceptance of the theory of warning
coloration as explaining certain extremely strikmg
colours and colour contrasts which occur throughout
the insect world. In cases of protective colouring, the

210

KNOWLEDGE & SCIENTIFIC. NEWS.

[Sept., 1904.

insects resembls more or less closely those objects by
which they are habitually surrounded — the protection
becoming more certain in proportion to the completeness
of the likeness. But with warning colours, exactly the
reverse is ^the case. Insects assignable to this class are
not coloured to be hidden, but in order that they may
readily be seen.

It is believed — and in many instances this is definitely
known to be the case — that such conspicuously coloured
insects possess some hurtful (|uality which renders them
inedible, and that their showy livery acts as a warning
to insectivorous creatures in general. The reason why
warning colours are thought to benefit a species is
explained in the following manner. Insects are, for the
most part, very frail creatures, and one peck from a bird
bent upon testing the edibility of (say) a caterpillar,
would, in all probability, result in the creature's death.
Thus, the mere fact of its being unsuitable for food
would be of no avail in savins; its life. But if the cater-

I— i/.;.i.inia ,h„rith„,:vi. 2—HeluuJ,ifi,iu,iina. Ex Trop. South America.
The Heliconiida; have all dark brown or black wings, lined or
spotted with very brilliant colours.

pillar were coloured in a manner sufficiently striking to
become impressed upon the mind of the bird, a distinct
advantage to the species might be expected to result.
For the bird, presuming it to be capable of learning a
lesson, would give up " experimental tasting " in so far
as insects coloured in a similar manner were concerned.
As an example of a warning colour combination by
no means uncommon in the insect world, the caterpillar
of the Cinabar moth [Euchclia jacobacT) which is zebra
striped in alternate bands of black and yellow, may be
cited. This larva has been proved to be nauseous in
taste, and to be rarely eaten by birds or other insecti-
vorous creatures old enough to have gained experience
in " the ways of the world." The same yellow and
black striping is to be seen upon the bodies of many
species of wasps and bees— insects which would prove
very unsatisfactory eating on account of their poisonous
stings.

The theory of warning coloration was first suggested
by Dr. A. R. Wallace to account for the extremely
bright colours exhibited by certain caterpillars. It has
since been applied to whole tribes of insects, of all
orders ; and so strong is the evidence in its fa\-our— the
result of systematic experiments conducted in various
latitudes with birds, lizards, and other insect-eating

creatures — that what was originally a theory may now
fairly be regarded as a well-established fact. Indeed, so
distinct are the colours and colour combinations possessed
by inedible species, and so unlike are they to the colours
of insects which do not possess noxious qualities, that
the student is frequently able to tell at a glance whether
a given species is an example of warning coloration or
not, even though he may never before have seen it.

Amongst butterflies, the examples of warning liveries
are particularly striking.

.Icrat'd sp. Ex Sierra Leone (fore wings sooty, black spots; hind wings
brick red, black spots .)

In South America, the "protected" species — as those
which possess some noxious quality are usually termed —
are exceedingly numerous, and are well typified by such
genera as MdJwma, Mclinca, and Hcliconiiis. These
butterflies are rendered inedible by the acrid or evil-
smelling juices contained in their bodies. Even in the
case of long-dead specimens which have been temporarily

Aiii'iini^i ochl<a. Ex 5outh Africa iblackish = brown, with white areas},

relaxed for setting, the unpleasant odour of these juices
is very apparent, resembling the scent which is left upon
the fingers after handling a ladybird beetle. Such
butterflies, in common with other evil-tasting species in
other parts of the world, are slow and measured in their
flight, fluttering in an unconcerned manner from flower
to flower as though experience had taught them that
they have little to fear from birds, reptiles, monkeys and
other enemies to insect life.

Although the species of warningly coloured butterflies
are exceedingly numerous in the New World, tliey arc

Sept.. 1Q04.I

KNOWLEDGE & SCIENTIFIC NEWS.

211

b\ ;;„ :...,..,: ...... ,.^,.oiued ill olhcr parts of the ^lob.-.

In Africa, the £;enera Acrafa and Aiiuiuris have a wide
range, and are represented by many well-marked species.
While in the Indo-Malayan region the great sub-family
of the Diinaiiuie, all the members of whicii are rendered
conspicuous by their warning liveries, is a dominant
group.

The accompanying photographs represent a few
common and very typical warningly coloured butter-

DanaU t-dmjn<H. Ex Philippines (white and blacki.

flies, and a glance at them will give the reader a better
idea of the special designs associated with inedibility than
could be gained from a mere description. It will be seen
that the aim is to produce a startling effect ; one, more-
over, that will not easily be overlooked or confused.
On contrasting such warning liveries with the tints of
insects which are wholly or partially protectively coloured
to harmonise with their surroundings, it becomes very
obvious that designs so different must have been pro-

Danaia Chtyaippus. Widely distributed in Eastern Hemisphere fulvous-
brown, marked with black and white .

duced in response to equally diverse circumstances. It
is, moreover, worthy of note that warningly coloured
butterflies, as a rule, differ little in the tinting of the
upper and under surfaces of their wings ; whereas
butterflies unprotected by inedible qualities, even tiiough
they may possess brightly coloured upper surfaces to
their wings, usually have them tinted beneath in harmony
with leaves, bark, sand or rock. Thus, as soon as they
settle with folded wings, their protective colouring comes
into play.

Modern Cosmogonies.

By Miss .-\gni;s Ci,i:rki;.

X. — The Forms of Nebulae.

.Siu \\'ii.i.i.\.M lii:KsciiEl.'s celestial surveys lirst made
the classification of nebuhe [)racticable. Until he
Iieyan grinding specula at Halh very few such objects
were known, and those too imperfectly for the effectual
discrimination of their differences. Arrangement pre-
supposes comparison, and comparison some variety of
■specimens to be compared, which became available
only through Ilerschel's scrutiny. The rapidity and
penetrative power of his oljservations in this field
almost passes belief. He detected with discernment.
Discovery and enrolment did not satisfy him ; he was,
besides, keen to note analogies and contr.nsts, likenesses
and dissimilitudes. He could not see without ;it the
same time setting in order w hat he saw ; and the law
of order that commended itself to him was founded on
an evolutionary principle. The contents of the heavens
seemed to fall spontaneously, as he regarded them, into
genetic sequences ; and the neliuke with particular
facility. The criterion adopted was that of progressive
condensation. Development must clearly, he judged,
be attended by contraction and local brightening.
Diffused milky tracts represented cosmic formations in
their most rudimentary form ; they assumed, through
the unremitting action of gravity in drawing their
particles together, a more compact texture, riiore
definite shapes, and a heightened lustre.

L5ut things ha\e changed somewhat in aspect during
the last hundred years. Herschel's simple rule of
.arrangement, although of unquestioned validity, needs
to be supplemented by others. Much auxiliary know-
ledge has been acquired since it was formulated. In
.ittempting to estimate the comparative antiquity of
nebula, we no longer depend exclusively upon one set
of indications. The conclusions drawn from their im-
mediate inspection can at least be checked by the study
ol their spectra and distribution.

The .Milky Way might be figuratively described as
tile nursery-garden from whicli the parterres of the
universe are stocked. A primitive condition is usually
•assigned, not without good reason, to any class of
objects markedly tending to collect in its plane. And
this is the case with gaseous, or " green " neljuke.
.Moreover, their materials appear to be in a highly ele-
mentary state tif it be permissible to speak of one kind
of matter as more elementary than another) ; their
spectra including no rays due to metallic incandescence,
but mainly those of nebulium, hydrogen, and helium.
These substances, inconceivably attenuated, constitute
the vast irregular formations placed by Herschel at, or
near, the start of cosmical development. And so far
he has been justified by the outcome of modern re-
search. But he has not been justified in his descrip-
tion of planetary ncbukc as " very aged, and drawing
on towards a period of change or dissolution." For,
despite their determinate shape and definite boundaries,
they do not appreciably differ in composition from
iiel)ul;eof the " irregular " class, and must be reckoned
as, in a manner, coev.il with them.

There is, on the whole, a concurrence of evidence
that gaseous nebulffi are at a very early stage of
growth. They are the least elaborated of sidereal ob-
jects ; they seem, many of them, barely to have crossed

212

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

the threshold of creation. Their mutual relations in
time are, however, by no means obvious. 1 hey can-
not easily be disposed in any kind of sequence. Each
of the great nebula;, at any rate, exhibits features and
occupies a position shared by none of its fellows. The
most discerning cosmologist cannot pretend to say that
the .Argo nebula, for instance, is of greater or less
antiquity than the Orion or the "America" nebula.
They are individual growths, simultaneous, not
successive. The line of development indicated for
them is rather towards the formation of star-clusters
than of diverse nebular species. Thus the Pleiades
may illustrate the probable future condition of the
Orion nebula, the contained stars having gained pre-
dominance, though still wrapt in filmy swaddling-
bands, later, presumably, to be shaken off.

I^lanetarv nebula? have much more in common than
irregular nebula?, and their minor varieties might, with
some plausibility, be associated with differences in rela-
tive age. They are marked chiefly by the character of
the nuclear star which, in nearly all such objects, ap-
pears to act as the pivot of the surrounding vaporous
structure. The supposition lies close at hand that it is
designed as a provision for the nourishment of the star
— that the star gains in mass and light at the expense
of the nebula, which it is eventually destined to absorb
wholly and supersede. On this view, planetaries like
the green glow-lamp at the pole of the ecliptic (N.G.C.
6543) should be regarded as the most advanced, while
Webb's planetary in Cygnus (X.G.C. 7027) would
exemplify an inchoate condition. In the former the
central star is of 9.6 magnitude, and sharply stellar ; in
the latter it is double and diffuse,* perhaps a wide
binary system in embryo.

The question is, howev-er, still open as to the real
nature of the connection between planetaries and their
central stars. The pabulum-theory is a promising con-
jecture ; but no facts with which we are acquainted
stringently enforce it. Ideas on the subject will need
complete revision if the traces of spirality noted from
lime to time in some of these peculiar objects prove to
be of radical significance. The oadi, distinctive of the
"Owl nebula" (N.G.C. 3587) as originally shown by the
Parsonstown reflector, consisted of luminous traceries
coiled round /ico interior stars, t but the appearance was
either due to illusion, or became effaced by change,
since the camera has refused to endorse it as genuine.
The " helical " planetary in Draco, i however, is doubt-
less essentially a spiral conformation § ; and Professor
Schacberle, by means of exposures with a thirteen-inch
reflector of twenty inches focus, has compelled not only
the Ring nebula in Lyra, II but the Dumb-bell in Vul-
pecula to betray the surprising secret of their whorled
structuri-. Both these nebulic give a spectrum of
bright lines, and invention is baffled by the problem of
building up gaseous m.iterials into strongly charac-
terised edifices. The materials, however, mav not be
purely gaseous ;• or we possibly see (as Professor
Darwin long ago suggested) merely illuminated stream-
lines of motion furrowing .-m obscure mass. But if
this be indeed so, there is the further question to be
asked : AVhat direction does the motion take? Do the
tides set inward or oxitward?

•Keeler, Lick Publications, Vol. III., p. 21.4.

IRosse. Trans. Roy. Dublin Sorictv, Vol II,. p. 93.

J First detected as such bv Holden .ind Schaeherle in 1SS8,

Monthly Notices. Vol. XI.VIII. p. 38S.
S Deslandres. Bull. .-Islr., Feb. 1900.
'! .4str. Jour, Nos. 539, 547
"^Maunder, Knou'lcdge, Vol. XIX , p. 39.

Our spontaneous impressions are all in favour of
concentrative tendencies. We cannot easily shake off
centripetal prejudices. Our lives are passed under a
regimen of central attraction, and we naturally incline
to universalise our experience. Hence Herschel's
scheme of sidereal evolution invites at first sight ready
acceptance. Stars seem as if they could not act other-
wise than as foci of condensation in nebula; ; the lucid
stuff involving them must, apparently, with the efflux
of ages, settle down towards their surfaces, and be-
come absorbed into their substance. Such processes
indeed, apart from counteracting causes, belong to
the inevitable order of Nature ; but these may, and
probably do, exist. From sundry quarters the con-
viction is pressed upon us that cosmic bodies can drive
out matter as well as draw it in. Repulsive forces
insist upon recognition, and their effects become more
palpable the more attentively they are considered.
Under certain conditions they get the better of gravity ;
and stars may possibly, like cocoon-spinning insects,
expend their organic energies in weaving themselves
unaccountably educed envelopes. The example of
Nova Persei is fresh in every mind, but we make no
pretension to decide the controversy it raised. A dog-
matic pronouncement is unadvisable where the un-
known elements of the question obscure and outweigh
those that are known. .A less slippery foundation for
reasoning is afforded by the permanently visible spiral
nebula;, and features charged with an emphatic mean-
ing have been revealed in them by photographic means.

Looking at the entire contents of the nebular
heavens, we find the spiral type very largely pre-
dominant. It claims more specimens, and emerges
more distinctly with each development of delineative
power. Its chief prevalence, however, is among
" w-hite " nebulee, showing continuous spectra.

They are vastly numerous. Gaseous nebulae are
reckoned by the score, white nebulae by tens of
thousands. Moreover, they collect near the poles of
the Milky Way,* while the gaseous variety crowd to-
wards its plane, both branches of the family thus
manifesting galactic relationships, though of an
opposite character. Now these facts of distribution
are not without indicative import as to relative age.
There is a consensus of opinion that objects showing a
marked preference for the Milky Way are at an earlier
stage of growth than those withdrawn from it, and the
inference derives countenance from the circumstance
that nebulae situated in high galactic latitudes shine
with continuous light, those near the galactic equator
with interrupted radiance. Vet it would be rash to
assume that any individual nebula traverses these
successive stages. The series could be satisfactorily
established only if we could point to a number of inter-
mediate instances, which seem to be almost wholly
lacking. We cannot trace in nebular as we can in
stellar growth the insensible gradations of progressive
change- They are, perhaps, complicated in nebulae by
influences of a different kind from those which have
gained the ascendencv in stars. Diffusive effects may
in them be more conspicuous than concentrative
effects ;t or a balance may be temporarily struck be-
tween antagonistic tendencies.

Spiral conformation is the real crux of nebular
cosmogonv. The conditions from which it arises are

* Dr. Max Wolf places the point of nebular concentration in
R.A. 12'" 53", D. + 61° 20', that assigned to the galactic pole
being in R.A. la*" 49™ , D, + 62^. Kiinigstulil Publ. Bd. I. p. 174.

tT J. J. See, " Repulsive Forces in Nature." Pop. Asir., No.
100. Dec. 1902.

Sept., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

113

met with only in the sidereal heavens, but are there
widely prevalent. Thoiiyh remote from our experi-
ence, they are fundamental in the realms of space. If
we could define and comprehend them we should he in
a better position for determinin"^ the cosmical status of
nebulje.

The choice is open between two rival theories of
nebulous spirals. The first is the more obvious, and
readily falls in with admitted mechanical princijiles.
Sir Robert Ball has adopted and ingeniously adxocated
this view.

A globular collection of promiscuously revolving
particles inclines, if left to itself, to flatten down into
a disc. The reason is this : In a system of the kind,
moment of momentum is invariable, while energy con-
stantly diminishes. To render the contrast intelligible
we have only to consider that moment of momentum is
the algebraic sum of all the products of mass and
motion in the aggregation, reduced to, or projected
upon its " principal plane," while energy is independent
of the varied directions of velocity. Collisions con-
sequently involve no diminution of moment of
momentum, but combine with radiative waste to pro-
duce a steady loss of energy. Inevitably, then, the
system will assume the form in which it possesses the
minimum of energy that is consistent with the main-
tenance of its original momentum ; and it is that of a
disc extended in the principal plane. Retrograde
movements will by this time have become eliminated ;
the constituent particles circulate unanimously in one
direction ; and Sir Robert Ball adds that their circula-
tion, owing to the more rapid rotation of the central
mass, is along spiral paths. * They would accordingly
present the twisted conformation so commonly ob-
served in the heavens, and might even include sub-
ordinate centres of attraction, fitted to ripen and
strengthen into a full-blown retinue of planets. .Such
are spiral nebula? regarded in their direct mcchanic.-il
aspect. .Spherical ncbuhe are their immediate progeni-
tors ; suns, with or without trains of dependent worlds,
their lineal descendants.

Let us, however, consult some autographic records
and weigh attentively what these peculiar objects tell
us about themselves. We see at once that their curving
lines are not laid dow n at hap-hazard, but according to
a strictly defined plan. Spiral nebuhc are not formed
like watch-springs by the windings of a single thread.
They are always two-branched. From opposite ex-
tremities of an elongated nucleus issue a pair of
nebulous arms, which enfold it in double convolutions.
Their apparent superposition and interlacements oc-
casion, in the Lyra nebula, the noted effect of a fringed
and ruptured annulus, and it is of profound interest to
perceive that even in gaseous masses the same cf)M-
-Structive rule prevails as in the great Whirlpool in
Canes Venatici.

It is, however, almost irreconcilable with the
hypothesis that an influx of material is in progress.
Falls due to gravity could not be limited to two narrow
areas on the central body. Matter ejected from it
might, on the other hand, quite conceivably follow this
course. Interior strain could easily be supposed to
cause yielding along a given diameter, and nowhere
else. Solar disturb;inces partially and dimly illustrate
such a mode of action. Diametrically opposite
prominences are not unknown. They indicate the
action of an explosive force right across the solar
globe. Similarly, the formation of a spiral nebula can-

* The Earth's Beginnings, pp. '243-7.

not be rightly apprehended otherwise than as the out-
come of long-conlinued, oppositelv directed eruptions.
The history of the hea\ens imolves the law ol
spirality. The scope ol its (ioniiiiion conliiuialh' widens
.is research becomes intensified. 1 lu' lluygenian
" portent " in the Sworil of Orion now figures as
merely the nucleus of the " grcnt winding Nebula"
photographed by Professor W. II. I'ii kering in 1889.
That the vast nebulosity encompassing the I'lei.ules is
an analogous structure seems eminently probalilc,
Ihiiugh the brilli.ancy of the enclosed stellar group
obliterates most traces ol its ground-plan. 'i'he
magnitude of the phenomenon, we are told by Professor
Harnard ' who (k^tected it in i<Scj3 by means of :i ten-
hours' exposure with the VV'illard lens, transcends our
[)owcrs of realisation. It covers 100 sc|uare degrees of
the sky with intricate details. About four minutes of
arc to the north-west of the King in Lyra lies .-i small
nebul.a discovered visually by Professor Karnaid in
i8()3, and photographically resohed by Keelcr into .1
delicate spiral. It is a two-branched, Irll-liaiuKd
spiral, as the large adjacent object has .also pioved to
be. One is, in fact, the miniature of the other, and ihey
are now shown, bv Professor .Schaeberle's short-focus
reflector, to be linked together by winding folds of
nebulosity into a compound spirrd system. The Dumb-
bell is held, on the same authority, to be similarly con-
ditioned, and the analftgv fre((uently noli'd in the
.aspects of these remarkable formations has thus be-
come incalculably widened in scale.

The galactic relations of the Magellanic Clouds are
not easily defined. They are within the Milky Way,
yet not of it. Enigmatical excrescences upon the uni-
verse, they suggest an origin from gigantic eddies in
the onflowing current of sidereal arrangement. Their
miscellaneous contents are, at any rate, disposed along
eddying lines. Mr. H. C. Russell's photographs I
rendered t.his, in 1890, to some extent m.anifest, and
their indications were ratified by the Arequipa plates
from the study of which Professor flickering gained
the conviction that the great Looped Nebul.i, 30
Doradus, is the structm-al nucleus of the Nubecida
Major. " It seems," he wrote, 1 " to b"e the centre of
a great spiral, and to bear the relation to the entire
system that the nebula in Orion bears to the great
spir.al nebula which covers a Large p;ut of lli;if con-
slell.ation."

On all sides, in the sidereal heavens, v\e can discern
the signs of the working of a law of convolution.
Sometimes they are patent to view ; sometimes half-
submerged ; but they can generally, with attention, be
disentangled from overlaying ajjpearani'es. They are
exhibited by stars no less than by nebida>, as the late
Dr. Roberts pointed out from convincing i)hotogra])hic
evidence ; the " hairy " ai)pen(lages of globular
clusters betray them by their curvilinear forms ; they
miH-t us in every corner of the wide nebular re:ilm'.
.M.-iny investigators recognise in the Milky Way itself
the stamp of spirality. Stephen Alexander, of Xew
jersey, S regarded the majestic galactic arch as a four-
branched .spiral, resulting from catastrophic breaches
in a primitive, equatorially loaded spheroid, thesti-eams
of matter eject(-d by which shoidd, owing to their lower
angular rotation, lag behind as they retreated from
the nucleus, and thus flow along helicoidal lines.
R. .'\. Proctor subsequently devised convoluted

'Monthh Notices. Vol. LX., p. 259.
1 Sec K,wideJi;e. Vol. XIV., p. 50,
; Ihuvard Annals, Vol. XXVI, p. 206.
J Astr.Jour., Vol, H., p, 100, 1852.

214

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

galactic streams, which, however, corresponded im-
perfectly with what the sky showed. And Al. Easton -
has designed an elaborate scries of spires, originating
possibly from that vague entity, the " solar cluster,"
the projection of which upon the sphere may, he thinks,
account for the noted peculiarities of the Milky Way.
Our interior situation, nevertheless, makes it extremely
diflicult to determine the real relations in space of the
star-streams circling around it. The observed facts
are, perhaps, equally compatible with many other
structural schemes besides those based on the idea of
spirality ; and the wiser course may be to adopt none,
for the present, with settled conviiiion. We can, how-
e\er, gather one sufiiciently definite piece of informa-
tion regarding the history of the Cosmos. All the in-
mates of the hea\ens, stellar and nebular, represent
quite evidently the debris of a primitive rotating
spheroid. Its equator is still marked by the galactic
annulus, its poles by a double canopy of white nebula.
The gyrating movement which it once possessed as a
whole doubtless survives in its parts, but ages must
elapse before the fundamental sidereal drift can be
elicited.

'Astrjfli.Ji'iir , Vol XII. p. 158.

Vacriacbility in

Sociology.— I.

By J. Collier.

To most readers, perhaps, and certainly to all non-
biologists, the chapter in Darivitiisin on the variability of
species in a state of nature must have been nothing less
tlian a revelation. Did the elder naturalists believe tnat
Nature, ha\ing once for all formed her moulds and
run into them her myriad species, had then gone to
sleep ? Here she was shown to have broken all moulds
or to be incessantly making new ones. Did thinkers
who accepted Darwinism, but were unwilling to aban-
don metaphysics, mythologically conceive of the
creative power as pushing ever upwards along certain
definite lines towards a dimly perceived goal? Here
was the old Proteus found to be mocking all predeter-
mined plans, flowing in all directions, taking all shapes,
and masquerading in all guises. The entire vegetable
and animal world was observed to be, as Heraclitus
of old vaguely guessed, in constant flux. Every organ
;uid every attribute of every species knows of no
stationary state, but changes continually, and on this
base of shifting quicksand is securely founded the
whole theory of biological evolution. On the same
foundation rests all social evolution. A rich harvest is
impossible in a still unploughed field, but an initial at-
tempt is now made to prove that the same universality
of variation prevails among sociological as among bio-
logical species.

Political.

The social organism resemlsles certain low animal
organisms, and like them varies in size. By annexa-
tions, renunciations, and losses, a country thus varies
from one generation to another, and such variations
may affect its specific character. The composite
Austrian Empire, before Hungary was granted its old
franchises, was predominantly German, and its
chancellors were German ; with the enfranchisement of

Hungary it became almost Hungarian, and had a
Hungarian chancellor ; since the annexation of Bosnia
and Herzegovina in 1S78 it has become pre-eminently
a Slavonic power, and naturally has a Slavonic chan-
cellor. By the annexation of Alsace and Lorraine in the
seventeenth century, E'rance gained a footing on the
right bank of the Rhine and at the same time acquired
a notable influence over German courts and German
literature ; since its lo.ss of them, its political and
literary influence has almost vanished. World-wide
Spain controlled the policy of the Papacy in the six-
teenth century, was dominant in the Council of Trent,
and deeply influenced the literature of Europe ; without
her empire she has shrunk to the dimensions of a
merely national organism. The extent of the English
county measured the personal force of the count or
earl and varied with that ; how significantly this con-
traction or expansion may affect a whole people, we
perceive from the part that the two large provinces of
Yorkshire and Lancashire played all through last cen-
tury in the public life of England.

The relative dimensions of social organism continu-
ally vary. The French ancicii regime was the scene of in-
cessant conflicts among the executive, legislative, and
judicial bodies. By their refusal to register royal
edicts and ordinances, by the amendments they made
in them, and the regulations they annexed to them,
the parlcniciits (courts of justice) constantly encroached
on the legislative power. They encroached on the
Executi\e by claiming the right to control the ad-
ministration and the finances. During the agitated
period of the Fronde they carried the assertion of these
prerogatives to the point of civil war. On the other
hand, the king trenched on the Judicature by the hear-
ing of appeals, by evocations to the privy council of
cases pending befere any of the courts, and by grant-
ing leave to individuals to plead before the privy coun-
cil in the first instance. The same variations are ob-
servable to-day. Lender the Second Empire the Judica-
ture was subservient to the Executive ; it has long
been subject to the Executive or the Legislature in
turn. These, again, continually encroach on one
another's sphere, now the one and now the other
basing the pre-eminence. The Judicature, in its turn,
p )aches on the preserves of the Legislature. " At a
lime of much hastily and recklessly devised legisla-
tion," remarks the Vicomte d'Avenel, " it illuminates,
corrects, completes, or lets fall into desuetude the in-
tentions of the law-makers. Reflecting changes of
cpinion and manners," he adds, "the jury is also
slowly re-making the penal code, repealing some of its
provisions bv refusing to give effect to them, modifying
others, ;ind practically instituting new penalties."

It was long a Liberal tradition that the history of
England records a steadfast constitutional develop-
ment from despotism to freedom. Its real evolution
might be graphically exhibited by means of such a
" diagram of variation " as will be found on p. 67 of
Wallace's Darwinism. While the dimensions of the
Kingdom or Empire have, on the whole, advanced, like
the body of .Sciurus there outlined, the chief organs —
the Executive, the Legislature, and the Judicature —
have grown by a succession of zig-zags, like the head,
tail, and feet of the same animal. Now this or the
other power is on the crest of the wave, now in the
trough of the sea ; and the variations are often steep
and abrupt.

It is equally an American tradition that the same
three great organs of the national life of the United
States have each been so effectually confined within
their peculiar spheres that they have never left them.

Sept., 1904.]

KNOWLEDGE & SCIENTIFIC NF.WS.

215

The illusion is less and is yet real. All thnuiL;h tluir
history each has pushed out in this direction and in
that. Rach has repeatedly tried to encroach on the
domain of the others. Sometimes the I'resident has
the upper hand ; sometimes Congress is on top ; and
the ."supreme Court is continually repressing the ex-
pansion of Congress. The Senate and the House ( f
Representatives are theoretically equal, hut the Senate
has grown at the expense of the House. In the .States
and the cities the Executive rises and falls with the
character of the (iovernor or the Mayor ; President
Cleveland was popularly known as the \'eto Mayor be-
cause of his unllinching exercise of his powers.

Ecclesiastical.

Perhaps it may he laid liow n as ;m axiom that all
Churches and all religions have hived off sects and
doctrinal varieties in exact proportion to their vitality.
Buddhism has shown the fertility proper to hot coun-
tries, though it is not in the hottest countries that it
has produced the most. While only eighteen sects
were counted in Ceylon and Tibet, Chinese Buddhism
has rejoiced in ninety-six.

Hinduism is equally marked by a propensity to de-
velop new forms. Sir Henry Maine describes the Sikh
religion as having a tendency to throw off sub-sects,
each with no\elties of doctrine and practice ; and he
adds that the same process goes on all over India.

L'nder the monotonous surface of Islam there is
incessant variation. According to Haron d'l--st()urnelle.s
de Constant, the Algerian sects are innumerable and too
fugitive to be seized. They appear, then suddenly dis-
appear, and unexpectedly reappear elsew here ; they
melt into one another, cross and ramify, change their
name and their doctrines.

Karly Christianity is the classical arena of sects and
heresies. Eternal truths, it has been well said, arc
those on which man has varied most. " Every year,
nay, every moon," wrote an ancient bishop, " we
make new creeds to describe invisible mysterii'S." Gib-
bon distinguishes eighteen ;\rian sects, but declines to
discriminate among the thousand shades of difference
between Xcstorius and Eutyches. In i<''43 a Jesuit
historian reckoned that there had been ninety heresies
in all, but the estimate falls far short of the reality.

The half-ossified Greek Church furnishes the same
evidence of vitality. Those best acquainted with
Russia assert that new sects are there continually
coming into existence, and that in such numbers as to
defy numeration.

A winding-sheet has long lain over the soul of Spain,
but its religious activity was at one time as great as
its military and colonial ardour, and a Spanish pro-
fessor has written a history of Spanish heresies in four
big volumes.

Catholicism has various types. The sensuous
Catholicism of the Italian differs from the sombre
Catholicism of the Spaniard or the semi-Protestant
Catholicism of the German. Travelling over tler-
many, M. Lavisse found different shades of piety in
different countries, showing the rich variety of the
religious sentiment. There is a great gulf fixed be-
tween the Ultra.montane Catholicism of Maynooth and
the very modern Catholicism of Baltimore.

Protestant Christianity is constantly hiving off new
sects : some twenty years ago the Times estimated that
700 distinct denominations were spread over the surface
of England. In the United States the number must be
still greater. " From Roger Williams and Ann
Hutchinson down to Abner Kneeland and William

Garrison," writes l-'merson about Boston, " there
never was wanting some thorn of innovation arid
heresy."

Military.

Incessant variation on an Ininuitable base is .ulmitted
by French military critics to be a summaiy ol the
history of the art of war. Procedures in use to-day
are thrown aside to-morrow ; rules valid one year are
found to be inapplicable the next ; and the tactics and
strategy of one campaign are obsolete in its successor.
Weapons arc taken up, and dropped, and takiMi up
again. Thus, the lance, which was being disused alter
the wars of iS()6 and 1870 had apparently shown its
inutility, came again into fashion before iSijo ; about
two years ago (so it was staled) all German ca\alry
regiments were to be armed with it ; since the Hcur
war it has been almost superseded by the rifle. The
primitive mode of lighting was by straggling bands ;
as nations grew more crowded their armies fought in
mass, and soldiers scorned to dodge a bullet or a
shell ; since iH7<} troops light in looser formation, as il
the individual had come to be of more account, .'\bout
1.SS9 charges of cav.alry in mass were again favoured ;
since the .South African war individualist lighting has
once inort' come into vogue ; but Germ;m military
critics predict that in future h"ur()])i'an wars battles will
be fought by gigantic masses, .\mong minor varia-
tions the .South African war gave new birth to the
mounted rilleman and the kli.aki uniform.

Ceremonial.

Habits and customs, manners and fashions obey the
same unchangeable law of change. Recreations vary
with the season and the year, and new ones are con-
tinually being devised. Croquet, tennis, rinking,
cycling, golf, and ping-pong chase one anotlier off the
field. Fashions in dress are still more fugitive. 1 he
succession of female fashions is believed to embody
the genius of caprice, but it could readily be shown
that there is no excess in female attire that has not
been matched and outdone by some whim or extrava-
gance in male attire. While admitting that women's
dress reveals " a great instability in details," Professor
George Darwin holds that it " retains a general
similarity from age to age." In point of fact, the
costume of men and women alike, in every single item,
has varied incessantly, in women no more than in men,
in men no more than in women. With the vanishing
of such a])paritions as Cintj-Mars, Beau Brummell, and
Count d'()rsay is not the scope of variation in male
clothing sensil)ly lessened? \ot by a hair's breadth.
The splendour is gone, but the variety remains. The
diagram of a century's coats would show hundreds of
variations. A simple calculation would prove that so
plain an article of male attire as a pair of trousers is
susceptible of thirty or forty different shapes, and the
tailor runs the gamut of most of them in a round of
years.

Linguistic.
Mechanical inventions are so many variations in the
practical sphere, and the records of the Patent Office
show that a successful invention is only one among
hundreds that have never come to fruition. But the
grand human invention is language, and it, too, has
grown by the selection of chance varieties among the
myriads to which hand and voice are ever giving birth.
The alphabet (to single out those arising from the art
of writing) has been the theatre of endless variations
that have not ceased even since the art of [)rinting laid
its leaden bands on the fluid mass. Place all existing

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KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

or extinct alphabets in parallel columns, and all will be
perceived to have sprung from a single ancestor —
Phoenician or transformed Egyptian. The developrnent
ha.s taken place in the manner of all organic evolution.
Spontaneous slight variations, due to accident, con-
venience, necessity, or caprice, have made all of the
daughter-alphabets to differ sensibly from the mother-
alphabet. In some letters a diagonal stroke has been
substituted for the perpendicular ; in others, a curve
gradually approaches the straight line, which ultimately
prevails. The position of an angle is changed ; a
flourish is added to a letter at the bottom ; a cross
stroke has a preponderance to one side ; a triangular
or circular top degenerates into a thick line ; other
characters rise above or descend below the line, or
shoot out at an angle ; and so on. How far such
fanciful variations may carry an alphabet we perceive
in Black Letter or Old English, which, or a congener
of it, has been stereotvped into the modern German
alphabet. Even printing does not arrest development,
but gives increased scope to it. The variants of the
artist who designs calendars and initial letters are of
the same nature as those which made the Etruscan
and Greek alphabets to differ from the Phcrnician.

Litera-ty and Aesthetic.

The range of variation is, perhaps, widest in poetry,
where the free spirit moves in an ideal world and half
creates its own objects. First, the rhythm varies. The
ancient Greek poets, Chaucer and the earlier English
poets, and all who trusted to their ear, "counted in
each line the accents and not the syllables."
With the loss of inspiration and the stiffening
of the resthetic sense, the fashion set in of
mechanically counting the .syllables, and we have
such poetry as Pope's. Chatterton and Coleridge
revived the old practice, converted it into a method,
and varied the double by a triple rhythm. Scott multi-
plied the variations, ringing the changes on " the posi-
tion of the accent in each foot, the number of the
accents, and the number of the syllables in each foot."
Next, the line, couplet, or stanza varies. In the first
history of English literature that has been fruitfully
impregnated by the evolutionist idea. Professor Mac-
millan Brown has luminously traced the variations of
metrical forms through the second half of the
eighteenth century. Two stand out conspicuous — the
heroic couplet and blank verse. In Milton blank verse
reaches the high-water mark by its cunning inversions,
its complex harmonies, and its sublimity. Then it is
displaced for half a century by the heroic couplet.
When it comes back its character has completely
changed. Descriptive in Thomson, stilted and ethical
in Akenside and Warton, simple and straightforward
in Cowper, picturesque and suggestive in Rogers and
Campbell, narrative in Southey and Landor, austere in
Wordsworth, and plastic in the Brownings, it is once
more richly musical in Tennyson. The rhymed couplet
runs a similar gamut of variations. Lastly, the struc-
ture of the poem varies. There are five standard types
of the sonnet ; there are six chief variations of it in
Italy, where it has been most cultivated ; the French,
too, have delighted in experimenting on it, and there is
a succession of English varieties ; while the sextet, or
group of six concluding lines, has been rhymed in
eighteen different manners.

It might be better to say nothing than to say too
little on the highest province of man's activity, but a
single instance may be adduced from the zesthetic
sphere. Hardly anything seems more likely to be

stereotyped than the music of an oratorio. Yet great
diversities have marked both the score and the per-
formance of the Messiah. The score has been edited
by a succession of musicians. Mozart supplied new
harmonies and new accompaniments. Hiller in-
corporated a version of his own with Mozart's score.
Bridge tried to restore it as Handel left it. Prout fills
up vacant harmonies, eliminates some additions, re-
stores Handel's orchestration, and deletes Mozart's
false counterpoint. To changes of score have been
added variations of performance : the harpsichord has
been disused ; the organ is larger ; the composition of
the orchestra has varied at different periods ; as have
also the proportions of the band and the chorus. There
have been many ^lessia/is.

.Such are a few examples, culled from a multitude, of
variations among sociological species. Evidently, the
genius of variety, which has made the outer world so
Ijright to eye and ear, has clothed in shapes as multi-
form the far more complex world of man's social
strivings and achievements. May we not conclude that
civil as well as natural history presents unasked all
those new openings and new paths which, selected and
pursued, lead to higher stages of ci\ ilisation ?

Some Tibetan Animals.

By R. Lydekker.

Naturalists are speculating whether the opening-up
of Tibet, which is practically sure to follow the present
expedition to Lhasa, will result in the discovery of any
new animals of special interest. So far as the smaller
mammals, such as mice, rats, squirrels, shrews, &c., are
concerned, it cannot be doubted that systematic collecting
will be sure to yield a certain number of new forms.
With regard to the larger mammals, the case is, how-
ever, different, and it would be unwise to expect that any
strikingly new type is likely to turn up, although important
information will doubtless be obtained in due course with
regard to the mode of life and the nature of the habitat
of several of the mammals already known to us. The
reasons for taking this somewhat discouraging view as
to the prospects of discovering new animals of large size
in Tibet are as follows : —

In the first place, although few Europeans have hitherto
actually reached Lhasa, the country has been traversed to
the northwards of that city from east to west — notably,
by ^Messrs. Bower and Thorold in 1892 — by travellers
who have done all in their power to collect specimens of
the fauna; while many sportsmen, naturalists, and collec-
tors have penetrated far into the interior from either the
eastern or the western border. ^Moreover, the typical
Tibetan fauna inhabiting the high plateaus above 14,000
feet is closely allied to, if not absolutely identical with that
of Eastern Ladak, which lies within the limits of Kashmir
territory, and has therefore for many years past been
readily accessible to Europeans. On the other hand, the
mammals of the somewhat lower and apparently more or
less wooded districts forming the cistern portion of
Tibet range into the north-western provinces of China,
such as Shansi and Kansu, where they have of late years
been collected by ;\Ir. F. W. Styan, an English tea-
planter. Not that our information with regard to the
mammals of Eastern Tibet depends by any means solely
on the collections made in Kansu and Shansi. On the
contrary, the great French missionary explorer, Abbe

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KNOWLEDGE & SCIENTIFIC NEWS.

217

David, succeeded many years aijo in penetratinix into the
heart of the Moiipin district of Eastern Tibet, whence lie
brought back a number of mammals belonging to types
previouslj' unknown to science. Practically all that has
resulted from subsequent exploration and collection is to
prove the extension of the range of these peculiar types
into Western China, and to add to them a few species
differing only in comparatively trivial features. The
absence of any distinctly new types in this West Chinese
fauna seems to point to the improbability of any striking
novelty among the larger types of animal' life remaining
to be discovered in Tibet.

Of the strange animals first brought from Eastern
Tibet by .\bbe David, and subsetjuently obtained by Mr.
Styan in Western China, by far the most remarkable is

Fij:. I.— Great Pand;i.

the creature now known to naturalists as the great panda
(.■Eluropus melanohucits), although at one time denominated
the parti-coloured bear (fig. i). In appearance this animal
is, indeed, strangely bear-like, although far inferior
in bodily size to most members of the IJrsida ; the rudi-
mentary tail, plantigrade feet, short ears, and broad head
being all ursine features. Moreover, it is not a little
remarkable that a species of true bear {Ursiis pniiiwsus)
inhabiting Tibet not infrequently presents a type of
coloration approximating to that of the great panda, in
which the legs and under-parts, together with a band
across the shoulders and a ring round each eye, are sooty
black, while all the rest is pure white. On the other
hand, when the face of the great panda is compared with
that of the much smaller and long-tailed arboreal animal
inhabiting the Eastern Himalaya, and known as the true
panda (.blunts fulgens), a marked resemblance can be
detected, and when careful comparison between the teeth

Fig. 2. —Teeth of right side of jaw of (ireat i*anda.

and skeletons of the two animals is made, it becomes
apparent that the great panda is much more nearly related
to the long-tailed species than it is to the bears. In fact,
these two animals appear to be the Old W^jrld representa-
tives of the raccoons and coatis of America, and thus
afford one more instance of the close affinity existing
between the faunas of Eastern Asia and North America.
The teeth of the great panda (fig. 2) are most beautiful
and interesting objects — on the whole approaching much
nearer to those of the lesser panda than to the ursine
type. Of the habits of the great panda, we are at present
in complete ignorance ; but on this point we may hope
in time to be enlightened by the opening-up of Tibet.

Whether we may e\cr expect to sec such a wonderful
creature alive in the Regent's Park, it is diflicult even to
guess. Probably tlie great panda is a native of the more
or less wooded districts of ICastern Tibet, and not of the
arid and elevated central plateau.

The same must undoubtedly be the case with the
Tibetan snub-nosed monkey {Rhhioj^ithecus roxellatuv)
(fig. 3), which was likewise the lirst-known representa-
tive of a new generic type discovered in the Moupin
district of Eastern Tibet by the .\bbc David. It has,
however, been subsecpicntly obtained in Szechuan, while
a second representative of the genus has been discovered
in WW. China and a third in the mountains bordorin"

rtta

^mmm

Fig .?.— Orange Snub-nosed Monkey.

the Mekong River. That the Tibetan representative of
the snub nosed monkeys, at all events, is a native of a
cold climate may be inferred from its massive and
"chubby" build and its thick coat, which in winter
forms a long silky mantle of great beauty on the back.
As to the peculiar form of the nose, so utterly unlike that
of ordinary monkeys, the suspicion arises that it may be
in some way connected with life at a high altitude, seeing
that the Chiru antelope, to be noticed later on, has gone
in for a very strange development in the way of noses.
At present, however, we are very much in the dark as to
the relative height of the districts in which these strange
monkeys are found.

Nothing special need be said with regard to the above-
mentioned Tibetan bear, except that it appears to be a
peculiar species. The mere mention that the snow-
leopard (FcUs uncia) is an inhabitant of the Tibet plateau
must likewise suffice, seeing that this handsome cat has
a wide range in Central Asia.

Several species ofdeer are found in or near Tibet, although
all of them appear to be confined to the wooded districts
bordering the arid central plateau. The finest of these
is undoubtedly the shou {Ccrvus ajftnis), a species allied
to the red deer, inhabiting the forests somewhere near
the head of the Chuinbi Valley, in Sikhim. This deer is
very rare in collections, where it is represented n^ainly
by skulls and antlers, but it is probable that specimens
will before long be forthconu'ng. A young individual is
stated to have been killed during the early days of the
Tibet expedition. Thorold's deer (C. alhirostris) is a
rather smaller and much darker coloured species, readily
distinguished by its white muzzle and the comparatively
simple antlers. It exhibits the relatively heavy build
characteristic of species inhabiting cold countries. This
fine deer was first obtained in the wooded districts to
the north of Lhasa by the Russian explorer I^rzewalski,
and subsequently by the English traveller Dr. Thorold,
to whom the Pritish Museum is indebted for its speci-
men. The third deer peculiar to the country is the
Tibetan tufted deer (Elaphodus ccphalophus), a species of
the approximate size of a roebuck, and typifying a
peculiar genus. In general character this deer is nearly
related to the Indian and Malay muntjacs {Cci'viiliis), the

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KNOWLEDGE & SCIENTIFIC NEWS.

[^EPT , 1904.

bucks being armed with similar long tusks in the upper
jaw, but the antlers are even smaller than in the latter,
being reduced to mere knobs, and there are distinctive
peculiarities in the skull. This interesting deer was first
obtained by the Abbe David in the Moupin district of
Eastern Tibet, but a second species was soon afterwards
secured near Ningpo, in Eastern China, while a third kind
has recently been described from the mountains rear
Ichang, in Central China.

In hollow-hon.ed ruminants (oxen, sheep, antelopes,
iS:c.) Tibet is specially rich, many of the species being
peculiar to the country, where se\ eral of them are con-
fined to the high central arid plateau. The first place in
this group must undoubtedly be assigned to the yak
{Bos grniniiciis), one of the finest and largest of the
wild oxen, specially characterised by the great growth of
long shaggy hair along the flanks and under-parts of the
body and the well-known bushy tail. In this country,
unfortunately, a somewhat false impression of the yak is
prevalent, owing to the fact that all the specimens hitherto
imported belong either to a small domesticated breed from
Darjiling, or to half-breeds; the latter being generally black
and white, instead of the uniform black distinctive of the
pure-bred and wild animal. None of such half-breeds
can compare with the magnificent half-tamed animals
kept by the natives of the elevated Rupsu plateau, to
the south of the Indus, where they afford the only means
of transport by this route between Ladaic and India.
And even these Rupsu beasts are inferior to the wild yak,
which stands nearly six feet at the shoulder. These
magnificent animals are absolutely confined to the arid
central plateau, on some parts of which, hitherto closed
to Europeans, they are said to be comparatively
numerous.

Another native of the same bare plateau is the Tibetan
argali, or wild sheep (Oris iiwwoii Itodgsoni ), amAgnihcent
animal, with horns of wonderfully massive proportions in
the old rams. Since, however, this species is only a local
variety of the true argali of Central Asia generally, it is
of less interest than the types exclusively confined to the
country. The same may be said of the shapoo, or Tibetan
urial (Oris vignei), which is the typical race of a smaller
race of wild sheep, whose range extends in one direction
into North-Western India and in another into Persia. A
third species of wild sheep, the bharal, or blue sheep (Oris
nahtira), readily distinguished by its smooth and peculiarly
curved horns and close grey-blue coat with black points,
is, however, absolutely characteristic of the arid Tibetan
plateau, on which it is found in large flocks. On the
other hand, the Asiatic ibex (Capra sihirica), which
frequents the more craggy ground instead of the rolling
uplands, is a species with a very wide distribution in
Central Asia.

Although the yak and the bharal may be regarded as
representing by themselves distinct subgeneric types, all
the hollow-horned ruminants hitherto mentioned are
members of widely-spread genera. We now come, how-
ever, to a remarkable species which is the sole represen-
tative of a genus quite apart from any other, and abso-
lutely restricted to the arid central plateau. This is the
graceful chiru, or Tibetan antelope ( Pantholops liodgsoni),
of which the bucks are armed with long, slender, and
heavily-ridged horns of an altogether peculiar type (fig. 4),
while the does are hornless. Eossibly this handsome
antelope may be the original of the mythical unicorn, a
solitary buck, when seen in profile, looking exactly as if it
had but a single long straight horn. Although far from
uncommon, chiru are very wary, and consequently
difficult to approach. Like all Tibetan animals, they
have a firm thick coat, formed in this instance of close

woolly hair of a grey fawn colour. The most peculiar
feature about the chiru is, however, its swollen, puffy
nose, which is probably connected with breathing a highly
rarified atmosphere. This antelope has never been ex-
hibited alive in a menagerie, and, as is the case with the
other large mammals of the central desert plateau of
Tibet, it would probably not live if removed from its
native uplands to ordinary levels. A second antelope
inhabiting the same country as the chiru is the goa
('G(7^('//rt/'/(-('/t-fl;/rfi(/(;j, a member of the gazelle group charac-
terised by the peculiar form of the horns of the bucks
and certain features of coloration, whereby it is markedly
distinguished from all its kindred save one or two other
Central Asiatic species.

The most remarkable of all the Tibetan hollow-horned
ruminants is, however, the takin {Biidorcas taxtcolor), of
which the typical representative inhabits the Mishmi
Hills, in the south-east corner of the country, immedi-

Fig. 4.— Head of Alale Chiru.

ately north of the Assam \'alley, while a second variety
is found further east, in the Moupin district. The takin,
which may be compared in size to a Kerry cow, is a
clumsily-built brute v;ith yellowish-brown hair and
curiously curved horns, which in some degree recall those
of the South African white-tailed gnu. Its nearest re-
latives appear to be the serows of the outer Himalaya
and the Malay countries, which are in many respects
intermediate between goats and antelopes. As it lacks
the thick woolly coat of the chiru and the goa, there
can be little doubt that it inhabits a country with a less
severe climate than that of the Central Tibetan plateau,
and it is probably a nati\'e of the more or less wooded
districts of comparatively low elevation forming the out-
skirts of Tibet. It is one of the few large animals that
hitherto appears never to have fallen to the rifle of a
European.

With the large and handsome wild ass or wild horse
(for it is, to a great extent, intermediate between the two),
locally known as the kiang, we return once more to a
characteristic denizen of the desert plateau forming the
heart of Tibet. The kiang [Eqnus hemionus kiang) stands

Sept., io

KNOWI.KDGK .K; SCIl'NTIFIC NM'WS.

2ig

close on 13 hands at the shoulder, and is of a bii^ht red
bay in colour, with the muzzle, under- parts, and lep;s
dazzling white. Its ears (Fig. _s) are relatively much shorter
and its hoofs much liroader than in the true wild asses of
Africa, from which it also differs markedly in colour,
while its cry is soniewhat between a bray and a neigh.
In the higher and more open parts of Ladak, kiang are
to be seen in large numbers ; and they come galloping
round the convoy of the traveller in circles, with their
heads carried high in the air, so that the face is almost
horizontal. Whether the kiang is entitled to be ranked
as a distinct species, or whether it should be regarded
merely as a variety of the chigetai or wild ass of Mongolia
and the lowlands of Central Asia generally, is a moot
point; but, be this as it may, the creature is absolutely
confined to the central desert plateau of Tibet, where in
winter it develops a coat as thick and rough as a door-
mat, in order to afford effectual protection against the
rigours of that season at such an altitude.

r.)

Fig. 5. Head of Kiang.

In addition to the foregoing list of large mammals,
Tibet is likewise the home of a number of peculiar species
of smaller size. Among these it must, however, suffice
to make mention of only two on the present occasion.
I'irstly, there is a remarkable species of water-shrew,
differing in many respects from the common water-shrew
{Neoiiiys fodieiis), and accordingly referred to a genus by
itself under the name of Neciogale eli'g(in<;. Of that genus
it is the sole known representative. When we are fully
acquainted with it, the Tibetan palm-civet (Paradoxuriis
laniger), at present known only by a single skin obtained
so long ago as 1836, will prove almost as interesting a
species, for it is quite probable that it will turn out to be
generically distinct from the palm-civets of India and
the Malay countries, from which it differs by its woolly
coat.

Such a large number of peculiar generic and specific
tjpes of mammals restricted to a continental area of the
comparatively small size of the Tibetan plateau is a
feature unparalleled elsewhere, and to find an analogous
instance we must take the case of an island like Celebes,
which has been isolated for ages from all surrounding
lands. It would seem, therefore, that Tibet has been
similarly isolated, so far as immigration and emigration
of its animal fauna is concerned, for a vast period of time ;
an insulation due, doubtless, to its great elevation above
the sea-level, and the consequent severity of its climate
and rarity of its atmosphere. Climatic peculiarities of
this nature can only be endured by animals specially
adapted to such conditions of existence ; and it is accord-
ingly only natural to expect that when once the Tibetan
fauna had become modified for the needs of its environ-
ment it would have remained permanently isolated from
that of the surrounding countries.

Photography.

Pure and Applied.

By Chapman Joni.s, F.I.C, F.C.S., &c.

Artificial lllitmination. — It seems not unlikely tliat all
our present methods of artificial illumination will be
regarded as elementary and crude in the not very distant
future. We aim at getting enough light, but arc not at
all particular as to its quality. When the colour of an
artificial light is modified, it is generally with the idea of
making the lamp more ornamental, rather than for the
sake of the light itself, for shades and globes are made
of all varieties of tint. The result is that coloured
objects appear difl'erent according to whether they are
\-iewed by daylight or lamplight, the variation extending
even to the character of the lamplight. For a long time
we were contented with analogous photographic discre-
pancies, using only plates that render bright yellow and
red as if they were dark grey or black, and some dark
blues as if they were white, but we are now becoming
alive to the importance of such errors. I have a piece
of plaid material that has broad stripes of a light brick
red, and a dark blue, which if photographed on an
ordinary or even an isochromatic plate, shows no trace
of the pattern. A photographic falsification of this kind
would not be tolerated, but such a change as I noticed a
little while ago, when a blue silk dress appeared to be a
rich brown by the artificial light provided, would
probably either pass unobserved or be regarded as a
curious and unavoidable incident. It may be argued
that daylight changes, and so indeed it does. Reds are
hardly distinguishable from black, and blues and greens
become grey as the night approaches, and twilight is the
more beautiful because of it. But to bring the changes
that are associated with the dying day into the full glare
of a brilliant illumination ought to offend our good taste.
A step forward in artificial illumination has recently been
made by Messrs. W. M. Gardner and A. Dufton in the
construction of a lamp for colour matching. They
employ an arc light, and by means of suitable media
absorb that part of the light that is excessive, and so
obtain an illumination which they state " is precisely of
the same character as that of good daylight from a north
sky, and has the advantage over ordinary daylight of
being perfectly uniform and unchangeable." Although
intended only for matching colours, the same principle
might be applied to ordinary illumination, and this offers
a far greater and more important field for such modifi-
cations of artificial lights.

The VariahiUly of JJaylig/il. — The changeable character
of daylight has a very large inlluence on photographic
work, and therefore must be studied by those who would
get better results than are obtained by the careless snap-
shotter. As the sun gets low the daylight gets markedly
more yellow, and we ha\e from time to time been in-
structed that the excessive l>lue sensitiveness of gelatino-
bromide plates becomes so far negatived on account of
this change that it is not necessary to obviate it by the
use of a yellow or orange-coloured screen. Whether (jr
not this is so depends on what the photographer wants
If he seeks to photograph an evening effect as if it were
lit by such light as is given by the sun only when he is
high up in the heavens, while the general effect is such as
can be obtained only when he approaches the horizon,
then he may omit the coloured screen. But if his aim is
to photograph the scene before him as it is, there is as

220

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

much need for the yellow screen at sunset as at midday.
The changes in light obviously affect all coloured objects.
If a photograph in natural colours is made so success-
fully that it is an exact reproduction of the original as
seen by full daylight, it may be different from the
original when they are compared by evening light, be-
cause the colours of the photograph are only imitations
of those of the object, and they may, and probably will,
be differently affected by the change in the character of
the light. If anyone desires a good illustration of the
effect on colours of daylight of different kinds, he has
only to get one of the separating black papers from a
" premo-film-pack " as supplied by the Kodak Company,
and see how the red printing on it appears by ordmary
daylight and again by twilight. He may find in the
latter case that the inscription has apparently vanished,
or, if he can see traces of it, he will probably be unable to
decipher it. If the red constituent of the light has gone,
a pure red will appear black and be indistinguishable
from it.

These changes in the light that reaches us from the
sun are generally ascribed to the terrestrial atmosphere,
particularly the aqueous vapour in it, and the fact that
the light from the sun has to pass through more and
more of the atmosphere as it sinks lower and lower.
But the sun also has an atmosphere, and it is possible
that variations in this may contribute to the changes that
we observe. Professor Langley, who has worked at this
subject for about thirty years, especially by means of his
bolometer, has recently stated that there is " an increasing
probability that the solar radiation itself varies in a
degree appreciable to our present means of daily observa-
tion, and a strengthening of the belief that it probably
varied through much greater ranges in the past, and may
do so again in the future."

Thi Keeping of Sensitive Plates. — The time that sensitive
material can be relied upon to maintain its good qualities
is of great practical interest. Plates in England, if stored
so that they shall be reasonably free from foul air, will
last a long time in good condition if the emulsion is not
very rapid. I recently had occasion to use some " spec-
trum " plates that are six years old, and found that they
had a full red and green sensitiveness, that they worked
clean, and, generally, were in good condition. They are
rather slow, for the most rapid spectrum plates are six or
eight times as fast. Slow plates of all kinds, if well
made, will keep in good condition for an astonishing
length of time. Ordinary fast isochromatic plates I have
found when a year or so old to require about double the
exposure they did when new, but otherwise satisfactory.
The ultra rapid plates, whether colour sensitised or not,
should be used as soon as possible after purchase. I
have found such plates when a few months old to be only
half as fast as at first, and to show considerable fog. It
is obvious that a higher degree of sensitiveness must
mean a want of stability, for sensitiveness and stability
are directly opposed to each other. While, therefore, it
is the makers' aim to provide plates that will keep well
under all ordinary conditions, the user of them should
bear in mind that high sensitiveness in plates means that
they are affected by very feeble forces, and as it is im-
possible to keep them isolated from adverse influences
whatever care is taken in their preservation, the more
sensitive a plate, other things being equal, the shorter its
life.

The Thornton I'ickard Co. has sent us a prospectus of their Annual
Competition, open to users of their apparatus. The prizes this
year consist of twenty equal amounts of £i in cash. The Com-
petition closes on October i, End full particulars and entry forms
may be had free on application to them at Altrincham.

ASTRONOMICAL.

The Ninth Satellite of Saturn.

It will be remembered that five years ago Prof. W. H. Picker-
ing announced the discovery of a new and faint satellite of
Saturn with a period of about a year and a half. The satellite,
to which he gave the name of Phcebe, was discovered upon
photographs taken with the 24-inch Bruce telescope. Eleven
photographs, taUen by Mr. Frost at the Arequipa Observa-
torv, under the direction of Prof. Bailey, have enabled Prof.
Pickering to follow the satellite from April 16 to June 9 of the
present year, and to correct its epbemeris ; and a full discus-
sion of its orbit will appear in a few weeks, in a forthcoming
volume of the Annals of the Harvard College Observatory.

Comet 1903 (Borrellyi and Light = Pressure-
in a paperin the " .Astrophysical Journal " forJuly.Mr. S. A.
Mitchell deals with the question of the formation of cometary
tails by the influence of light-pressure. The researches of
Bredichin had shown comets' tails to be of three different
tvpes according to the intensity of the repulsive forces which
Bredichin explained as electrical in nature. This Lebedew
showed not to have a sound physical basis, but .-^rrhenius has
recently substituted the pressure of light. For a little cube of
water with an edge of one micron, the pressure of the sun's
light on it, at the sun's surface, is exactly equal to its weight ;
for a smaller cube the pressure would he greater than the
weight, and hence the particle would be repelled. Measures
of the angles between the tails of Comet Borrelly and its
radius vector, made by Mr. Sebastian .Albrecht on thirty-two
photographs taken between June 22 and .\ugust 18, J903, gave
somewhat discordant results for the principal tail, but the
mean of the best values gives the repulsive force as i8'47
times gravity. The values for the secondary tail agreed much
better, and their mean was i'S24; the last four values gave a
mean of 1-460, seeming to show the existence of a third tail,
and this appeared to be corroborated from the photographs of
August 12 and 15. The size of the particles forming the tails
would be respectively o-i, i, and 1-33 microns. Mr. Mitchell
concludes that there seemed to be a lagging even behind the
direction given by the repulsive force : in other words, that
the value of the repulsive force may increase as the comet
approaches the sun. This increase, he considers, is in part at
least real, and due to the more violent action of the gases
liberated as the comet approaches the sun.

The Position of the Galactic Plane.

A most important and lucid paper by Professor Simon New-
comb has been published on the position of the galactic and
other principal planes toward which the stars tend to crowd.
He states the problem thus : •' It is well known that the sky
appears to us poorest in stars in the regions around the poles
of the galaxy, and that it continually grows richer at a rate
which is slow at first but more rapid afterwards, from the
poles to-vard the galactic circle." Within the galactic girdle,
the thickness of the stars in space is approximately constant,
but in the Milky Way itself it is obvious that it consists of
agglomerations of stars which have often fairly well defined
boundaries ; the stars here are much thicker than outside the
girdle. The chief object of this paper is to determine this
principal galactic plane, and abo to determine whether the
non-galactic stars condense towards this same plane or towards

1904]

KXOWT.l-PGI' c^- SCIENTIFIC NEWS.

221

other planes. Professor Newcomb m.ikes no hypothesis as to
the .ictiial thickness of stars in space, but considers only their
apparent distribution in the sky ; and the prol)lcin is thus
stated for mathematical discnssion : " Let us suppose a plane
taken at pleasure passing through our position in the universe,
which point we take as the origin of coordinates. This plane
will cut the celestial sphere in a great circle. The perpendi-
cular distance of a star from the plane will then be represented
by the sine of its distance from the great circle. Let us form
the sum of the squares of these sines for the whole system of
stars which we consider. The value of this sum will vary with
the position which we assign to the plane. The principal plane
of condensation, as I define it, is that for which the sum in
question is a minimum." The working out of these expressions
of condition gives a cubic equation whose three roots are the
three principal planes of the system of stars; the smallest root
corresponding to the plane of condensation, and the other
planes being at right angles to it. If the system of stars should
lie on a great circle then the value of the smallest root, corre-
sponding to the plane of condensation, will be iiero. In con-
sidering the galaxy a difficulty came up with regard to the
great bifurcation between Cygnus and Aquila, and Professor
Newcomb therefore considers two cases, one including the
branch in the galactic system, and one omitting it. In neither
of the two cases does he find that the central plane of the
galaxy is accurately a great circle in the sphere ; in other
words the solar system does not lie quite centrally within the
band of the Milky Way. Next Professor Newcomb considers
" The Belt," or band of bright stars which first -Sir John
Herschel and later Gould showed as lying on a great circle
which cut the plane of the galaxy at an angle of about 20".
Professor Newcomb shows indeed that this angle of deviation
from the plane of the galaxy is only about 11*.. from the con-
sideration of 36 of these bright stars which do not exhibit large
proper motion. Thirdly, he considers the plane of all stars to
mag. 2'5 ; of all stars to mag. y$ ; of all the lucid stars ; and
finally for the Wolf-Kayet or Fifth Type stars. The following
table gives the positions of the poles of these planes : —

Galactic plane (omitting branch)
Galactic piano (including branch)
Gould's Belt, as found by Gould
The Belt, from 36 stars of small p.m
Plane of all stars to mag. 2-5
Plane of all stars to mag. 35
Plane of all lucid stars
Plane of the fifth type stars

From a consideration of the richness of the galactic region,
Professor Newcomb concludes that if the galactic agglomera-
tions were excluded from consideration, the crowding of the
lucid stars towards their principal plane would be scarcely, if
at all, greater than what we might expect as the result of the
irregularity of chance distribution, and that we should still find
a continuous increase in the richness of the sky from the poles
to the galactic circle, where it would probably be nearly twice
as great as at the poles.

BOTANICAL.

R.A.

Dec.

192"' -8 .

. + 27-2

igi"-! .

26--8

I7l'^-2 .

30-0

179 C .

• ^6:4

iSi 2 .

17-4

180 'O .

2r-'-5

iSo -o .

21-5

190 9 .

26 7

Though the ovary of the oak (Qiunus) is usually more or
less perfectly three-celled, and each cell contains two ovules,
the mature fruit, known to everybody as the acorn, nearly
always contains only one seed, and therefore produces only
one seedling. Professor Coker, in the January number of the
Botanical Gazette, refers to acorns which invariably contain
two or three seeds, and one is illustrated giving rise to three
vigorous seedlings. These acorns were produced by a rock
chestnut oak {Qucrcus pniiiis), found near Baltimore, Mary-
land. The same writer has met with a two-seeded aconi of
O. vdutina, but in this instance the other acorns of the same
tree were one-seeded.

Professor Coker also has an interesting note in the same
publication on " Spore Distribution in Liverworts." He alludes
to the fact that terrestrial species usually have their capsules
raised on elongated stalks, while in the case of those that grow

on trees the stalk of the capsule is seldom long, as in the
latter the position of the plants some dist.incc' above tlic
ground ensures the distribution of the spores on the dehis-
cence of the capsules. He sliows, however, that in Poiilla
platyphylhi, though the vegetative shoots arc closely ad-
pressed to the bark of the tree, the fertile ones, just before
the ripening of the spores, bend away from it and often
project .a centimetre or more. In consequence of this the
spores get more exposure to winds, which prevent their fall-
ing and remaining amongst the leavers of the parent plant.

In recent volumes of the CmiiptiS Riiuliis, Monsieur G.
Bonnier has some interesting and important papers giving the
methods and results of his cultural experiments on plants in
the Mediterranean region, with a view to the modifications of
their anatomical structure. The experiments have been
carried on at Toulon, and at Fontainebleau, thirty-seven miles
S.S.K. of Paris. Fifty peremiial species were selected, each
of which was split into two portions, one for cultivation at
Toulon, the other at Fontainebleau. The plants were pro-
cured from the latter place, and the soil in which both sets
were cultivated from Toulon. The results obtained are very
interesting. Toulon has a less uniform climate than h"on-
tainebleau, and is drier in sununer, conditions which would
be expected to le.id to some modifications of the infernal
structure of the stems and leaves. The plants grown at
Toulon have acquired the same peculiarities of anatomical
structure as those of the plants of the same species found
growing wild in that locality. The annual ring of wood was
thicker and contained vessels of a larger calibre, while the leaf
characters were more xerophytic than in the Fontainebleau
specimens. Instances of remarkable variations in size and
habit of plants grown in different latitudes and at different
elevations are familiar to most botanists, and an extensive
knowledge of such variations is most important to the systema-
tist, who is often perplexed in determining whether characters
with which he has to deal are of specific value, or whether
they merely represent the influence of local conditions.

'S^^rrrs-

ORNITHOLOGICAL.

Bv W. P. PvcK,«T, .V.L.S,, F.Z.S., M.B.O.U., &c.

InfaLnticide by a Meadow Pipit.

Lord Balfourof BuRLEicH,inaletterto the Fitld for July 16,
describes, on the authority of his keeper, how a meadow-pipit
ejected its own young from the nest in favour of a young
cuckoo.

The foundling, it appears, emerged from the shell some forty-
eight hours after the first of the young pipits, but a few hours
later the pipit was found outside the nest. Knowing nothing
of the evil reputation of young cuckoos he replaced the nest-
ling and watched for the hatching of the remaining eggs.
This took place a few hours later, and he then saw what he
believed to be the hen bird " remove first one and then the
other and deposit her own offspring outside her home. Not
being yet satisfied, he put two of the young ones back into the
nest, and to avoid possibility of mistake watched operations a
second time. He again saw the unnatural mother eject her
own young in favour of the stranger. The young cuckoo was
fed and tended by both titlarks and a few days after left the
nest."

This account is certainly of extreme interest and is probably
unique. There can be no doubt about the fact that norm.dly
the young cuckoo performs the work of eviction. Indeed,
according to most observers, this little monster is specially
endowed by Nature with a hollow back into wliich the victims
are forced by the wings and held there till the edge of the nest
is reached, when they are toppled over. Concerning this
hollow back we shall have something to say later.

This letter was followed by another (July 23) from a corre-
spondent who, after reading Lord Balfour's letter and finding
dead wagtails outside the nest, came to the conclusion that

222

KNOWLEDGE & SCIENTIFIC NEWS.

[Se

1904.

this eviction must have been the work of the parent wagtails,
owing to the tender age and and helplessness of the cuckoo.
But this is purely supposition.

Cuckoo Watching over its Young.

The cuckoo would appear to be a much maligned bird, or at
least to be credited with fewer virtues than it really possesses.
In the Ficiii of August 6 a writer describes how a young and
full-fledged cuckoo was seen on a lawn making '■ a noise more
like squeaking than chirping," whilst overhead two old cuckoos
were hovering. On three consecutive days the same thing was
observed. In this account, however, there is no mention of
their tender solicitude taking a more practical shape, since
neither of the old birds appear to have fed their putative off-
spring. Since the cuckoo is well known to be a polygamist,
he is probably at most only mildly interested in anv of his
numerous oft'spring which must be scattered over the area of
his sojourn during his short stay in this country.

Sexual Differences in the Wing of the
La-pwing.

Hitherto the sexes of the lapwing ( I '(!);t7/!(5 cristatiis) have
been regarded by ornithologists as almost indistinguishable.
In the Fitld (July 161, Mr. F. W. Frohawk shows conclusively
that a very ready distinction maj' be drawn between the sexes
at all ages, inasmuch as in the male the primaries from the
3rd to the loth are both broader and longer than in the
female ; so much so that in the outstretched wing the primaries
of the male form a broad round fan projecting conspicuously
beyond the line of the free edge of the secondaries. Further,
in the male the secondaries grow shorter from without inwards
so as to impart a sinuous line to the free edge of this region of
the wing. It is strange that in so famihar a bird this difference
should so long have remained undetected. As Mr. Frohawk
points out, it is probably this great fan-shaped expansion of the
wing which makes the remarkable flight of the lapwing at the
breeding season possible.

Decrease in Weight of Incuba.ting Eggs.

Mr. H. S. Gladstone, in the last number of the Ibis, contri-
butes an [extremely interesting note wherein he shows, by a
series of careful weighings, that eggs lose in weight during
incubation. Experimenting with pheasants' eggs he shows, in
a table of averages, that between the first day and the twenty-
third the loss is as much as 2 drs. 12 grs. Weighed every
fourth day the loss on the average varies between 9 and 10 grs.
The history of any single egg is sometimes very striking; thus
an egg which, just laid, weighed 17 drs. ig grs. at the twentv-
tbird day only turned the scale at 13 drs. 10 grs.

Blue throat near London.

Mr. F. Chubb, in the ZvoUif^ist for Julv. records the occur-
rence of the Blue-throat (Cvmfti/i/a suai'a) at Sheen Connnon
on June 17. There can be no doubt about the identification
m this case, for he remarks: -'What struck me first was the
beautiful band of light blue round the throat. ... as it
settled on a fence within a few vards of where I stood."
Though he could not make oat the colour of the spot in the
throat, Mr. Chubb inclines to the belief that this bird was of
the red-spotted species, and in this we agree. The white spot
would have been conspicuous ; moreover it is a much rarer
visitor.

Long eared Owl Nesting on the Ground.

Since the long-eared owl (Asio ottis) very rarely nests on the
ground it is interesting to note that a further instance has
occurred at Witton Park, near Blackburn. A description of
the nest, together with an excellent picture of the female and
young, appears in the Zoulugist for J uly.

ZOOLOGICAL.

Gibbons in Sumatra.

According to Dr. \V. V'olz, who has recently been travelling
in the country, the two banks of the Lematang River in the
Palembang district of Sumatra are respectively inhabited by
diff^erent species of long-armed apes, or gibbons. On the
west bank is found the siamang {Hylobates syndactylus), while
the country to the east of the river is the home of the agile
gibbon, or wau-wau (//. a,i;ilis). It is notnecessary tocapture,
or even to see, specimens of the two species in order to satisfy
oneself as to their limitations, for they may be readily distin-
guished by their cries, the siamang calling in a single note,
whereas the cry of the wau-wau forms two notes. The re-
markable thing about their distribution in Palembang is that
the two species are found in company throughout the rest of
Sumatra; and even in Palembangitself they inhabit the moun-
tain districts, where the river is so narrow that they could
easily leap over it, and yet they keep to the opposite banks.

Papers R^ead.

At the meeting of the Entomological Society of London held
on June i, Colonel Sainhoe read a paper on Tropical
African moths of the family Giomctrida: ; Mr. W. L. Distant
contributed some notes on additions to our knowledge of the
cicalas (Cicadidiz) ; the President communicated an article by
Mr. G. F. Leigh on series of butterflies of the species Papilio
ceiu-a and Hypulimnas iiiisippus ; while Mr. E. Saunders de-
scribed collections of Hymenoptera from Majorca and Spain.

"f^ * *

Wild Asses and the Quagga.

The August issue of the Pruccedin^s of the Zoological Society
of London contains two coloured plates of Asiatic wild asses
now living in the Duke of Bedford's park at Woburn. The
two species portrayed are the kiang, or wild ass of Tibet, and
the chigetai, or wild ass of Mongolia. The description of the
two animals is by Mr. Lydekker, who, we understand, has
written a paper on wild asses generally, which will shortly be
pubhshed in Xovitiifes Zoologici^, the official journal of Mr.
Rothschilds splendid private museum at Tring. To the
journal first mentioned Mr. Lydekker also contributes some
notes on the extinct quagga, in which he confirms the alleged
existence in the skull of that species of a vestige of the cavity for
the face-gland which was fully developed in the ancestral three-
toed hipparion. He also refers to the recent gift to the British
Museum of a portion of the head-skin of a quagga shot in the
forties, which had been made into a sheath for a hunting-
knife.

* * *

The Lily-Cradled Bat.

A gorgeously coloured Oriental bat [Ctrivuii!ii picta), whose
wings are brilliant orange and black, has been generally sup-
posed to owe this coloration to a protective resemblance to
the decaying leaves and ripe fruit of the plantain, among
which it commonly dwells. A correspondent of Captain
Stanley Flower has, however, stated in one district of Siam
this bat reposes in the flower of the Cala lily. The colour of
this Uly is not stated, but it may be presumed that it is some-
what similar to that of the bat. In commenting on the state-
ment. Dr. Jentink, of Leyden, remarks that " it sounds like a
wonderful tale, a golden red and black coloured bat sleeping
in a Uly-fiower ! " Can it be that the plaintain bat has a
double colour-adaptation — to the plantain in India and to the
Cala lily in Siam ?

« * ♦

Alleged Cannibalism in Snakes.

In a recent issue of the Journal of the Bombay Natural
Historj- Society numerous instances are cited of snakes
devouriug one another ; this kind of diet being stigmatised as
'• cannibalism." Seeing, however, that in all the instances
cited in this particular communication the devourer was
of a different species to the one devoured, this is
surely a misnomer. We might as well say that it is canni-
balism on the part of a great grey shrike to kill and eat a
sparrow, or of a rat to devour a field-mouse. When, as
happened some years ago in the Zoological Society's Menagerie

Sept., 1904.'

KNOWLEDGE & SCIENTIFIC NEWS.

223

a python devours one of its own kind, \vc have an undoubted
case of cannilvilisni ; but it is highly improbable th.it acts of
this description ever take i>lace in a state of nature.

» * *

Black Leopards.

Many people persist in believing that the black leopard is a
distinct species. .\n addition.al piece of evidence that this is
not the case is alTorded by a correspondent of the huluiii I'iclil
newspaper, who writes that in the Bhanio district of Upper
Burma he reiently found a pair of leopard-cubs, one of which
was black and the other of the ordinary spotted type. The
tendency to blackness, or melanism, it may be noted, is most
marked in hot. moist climates, like that of the district in
question.

« * *

The World's Consumption of Ivory.

Our contemporary tlie /••,>if^ist lor M.iy List contained .1
verj' interesting article on the supply of ivory from the Congo
Free St.ate, and of the world's annual consumption of tills
commodity. .As regards the latter item, it .ippears that the
total reaches the enormous figure, on an average, of 647,000
kilos., of which India and China take 144,000 kilos., the rest
going to European markets. As regards the price of ivory, it
may be mentioned that .average tusks fetch froui 24 to 25
francs per kilo., white the round and full tusks of from 6 to .S
centimetres in diameter realize as much .is 30 francs per kilo.
On the other hand, the price of inferior descriptions is only
from 13 to 15 francs per kilo. A kilo, we may add. is equal to
2'204 lbs., that is to say practically ai lbs.
» * *

The Classification of Reptiles.

The relationships of the diiferent orders of living and extinct
reptiles and the best mode of illustrating these in systematic
classification are discussed by Mr. G. A. lioulenger, of the
British (.\atural History) Mu.seuin, in the August issue of
the Zoological Society's !''>-iici\-iliiii;s, at the end of a paper
on the skeleton of a curious little reptih; from the New
Red Sandstone of Elgin. It has of late years become
more and more evident that the remarkable e.\tinct anonio-
donts of the equivalent of the New Red Sandstone in .Africa
and el.sewhere differ very widely from all other reptiles, and
approach inammals, of which they were undoubtedly the
ancestors. For the first time this has been fully and definitely
recognized in classification by Mr. Boulenger, who now divides
reptiles into two brigades, the one including the anomodonts
and their immediate relatives, and the other all the rest. The
former brigade is termed Keptilia Theromora (= Thero-
raorpha),or .Mammal-like Reptiles, and the latter (from which
birds took their origin) Reptilia Herpetomorpha, or Reptile-
like Reptiles. In view of the fact that the latter combination
is nothing less than tautology, the substitution of Reptilia
Ornithomorpha (Bird-like Reptiles) maybe suggested; and
the two brigades would then be respectively known as the
Theromorpha and the Ornithomorpha. There can be no doubt
that Mr. Boulenger's classification is much superior to the
one recently proposed by Professor H. F. Osborn, of New
Haven, CS..\.

» » *

Corrigendum.

In the article on the Later History of the Horse in our
August issue cuts 2 and 3 are unfortunately transposed.

CORRESPONDENCE.

Sa.lmon irv Fresh Water.

Dr. Thom.\s B. Tucki;v writes: — That salmon never feed in
fresh water I cannot credit, notwithstanding all the evidence
adduced to the contrary. That no food has ever been found
in the stomach of a salmon caught in fresh water I can well
believe. I have the evidence of a man who fished the Black-
water in the South of Ireland ever since he could fish. This
man died only a couple of years ago. He was a grown man
before I was born, and I am a grandfather. This old man
told me only the ye.ar before he died that he had never found

.anything in a salmon's stomach. Nay, he told me of a salmon
which he once gatTed, supposing it to h.ive been a fish which
li.id broken away from some angler .and which had been
caught by the attached piece of line in a snag. To his astonish-
ment, he found that the fish was stone-blind, and h.id only
rudimentary eyes; it was, however, pluni]), and had all the
appearance of a newly-run fisli. But I have instituli^d
iiupiiries among the fishermen who take salmon in nets at
the mouth of Fowey Harbour, and also .unoiig those who
catch them in the tidal part of that river, ,ind thev have
assured my informer that, though in the habit of repeatedly
cleaning salmon after their capture, tliey h,i\c never found
any food in such salmon. Now, it is quite incredilile lh.it
salmon never feed either in the se.i or during their sojourn in
rivers, ;ind it is much more probable that the s.ime causes
operate on the salmon in both their salt and fresh water habi-
tats. We know how greedily they rise ;it the .artificial lly, an
object, to be sure, like notliing on e.irth or in the water, but
still the salmon must liken this bait to some natural object,
or they would not be .so fre<|uently caught by means
of it. A salmon's sole idea of a salmon fiy must be that
it is something eatable, otherwise it would not open its
mouth to get caught by the hook. But whatever objection
may be brought forward about the artifici.d fly, wli.it cm one
s,iy .about the worm, the minnow, , and the shrimp '.' The worm
the salmon h.is often seen floating by; the minnow .and the
slirinip swimming about in dozens, is it to be sujiposed that
the fish will only take one or the other of the latter when they
have a piece of gut attached to them. Such reasoning is truly
a rciluctio ml ahsurtliiiii .' I dares.ay th.it salmon find it hard to
support themselves in rivers, but Mr. .Mlalo, in his " Natural
History of the British Islands," states that " Salmon-roe is a
deadly and illegal bait for the fish themselves." Salmon-roe
is, I know, a deadly bait for trout. I liavc not heard of its
being used for salmon, but I am sure, if we are to judge by
the rest of his work, that he knows what he is writing about.

The true solution of the matter, I think, will be found,
when we know e.\ac(ly what the salmon's usual food is. I
should guess that in the sea it consists of jellyfish or some such
soft gelatinous food, that its digestion is very raiiid, and the
undigested residue \ery trifiing; and that in rivers the ova of
fish may make one of its principal meals. I have .also thought
that the iridescent colours of the artificial fly may, to the
salmon, similafe the appearance of jellyfish, some of which
when floating in the water display all manner of delicate and
beautiful colours. This, of course, is mere conjecture, but I
cannot fancy that a salmon swallows ,i mixture of gold twist
and jay feathers for the fiin of the thing, any more than I can
believe the old fox-hunter when he assertid that Reynard
liked being hunted.

REVIEWS OF BOOKS.

We have received from Messrs. Newton and Co., of Meet
Street, their new X-Ray catalogue, which includes informa-
tion of a comprehensive kind regarding the " .Apps-Newton "
induction coils, the mercury breaks of improved iiatterns, and
other apparatus for both experiment.il and pr.ictical work.
Messrs. Newton announce the install.ition on their premises
of an extremely useful switchboard equipment, by means
of which customers can make themselves familiar with its
use, and with the proper manipulation of their instruments.

The Ndiilidnif'loii Imlilutc and 'J'cchnical Optics. — In connec-
tion with the extremely useful classes in Technical Optics
which have been developed at the Northampton Institute by
Dr. Mullinciix Walmsley, and which have received the warm
support of the optical trade, a scholarslii]i has been instituted
by .'VIessrs. Aitchison, tobe called the " .'\itchison .Scholarship,"
which will defray the cost of the course of instruction of the
student who wins it in the Institute's IXiy Coursesof Technical
Optics for two years, and will leave him a small bal.ince in
addition. The full cour.se, as at present contempl.ited, extends
over two years, and consists of lectures, laboratory work,
drawing office work, tutorial classes, and workshop practice.
Partial courses, extending over three years, have been arr.inged
for those already engaged in some optical trail(>, and the
scheme must command the warmest supiiort of all interested
in British Technical and Optical industries.

224

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

Conducted by F. Shillington Scales, f.r.m.s.

CoccidoLe.

With Notes on Collecting a^nd
Preserving.

By /Xlice L. Embleton, B.Sc.

As greenhouse and garden pests, " scale insects " and
" mealy bugs " are only too well known to the florist
and horticulturist, for they abound in most climates,
particularly in the tropics. They are easily dis-
tinguished from other insects, being strikingly different
in many ways. The brown " currant scale "
(Leca7iium coryli) will serve as an example; or the brown
" peach scale " {Lecatmim persicum), both very serious
enemies to the fruit-grower in this country. The de-
scription applies almost as well to the dreaded vine
pest (P. I'iiis), which plays much havoc in wine-pro-
ducing countries, and equally truthfully to the common
brown scale on ferns and palms grown indoors
[Lccaiiiiim hanhphaericuni). These insects, and many
others, are very similar in appearance, and also agree
in .being of considerable economic importance. A
sketch of the scale found on the bark of currant bushes
will suffice to illustrate the general nature of these
creatures. In the adult stages they are firmly fixed to
the host plant, and appear as small brown convex
elevations, about one-eighth to one-sixth of an inch in
length; the convex dorsal shell still bears some trace of
a keel-like ridge running from back to front, sending
out transverse branches connecting this keel at right
angles to the limiting circumference. This description
is of the female, for the male is winged, is less common,
and has but a short life, so it may be left out of the
present description. To return to the adult female of
Lccanium coryli, it is found that under this hard, shining
brown carapace she lives and breeds. In the winter
her enveloping shell fits close to the surface to which it
is attached, and it needs care to remove the creature
uninjured; but in July one finds that the rounded
mother-shell is nothing but a tent covering a heap of
substance that looks like pink dust, but which is,
in reality, the mass of eggs of the coccid. In a short
time these eggs give rise to small yellow six-legged
larva?, which move about restlessly all over the parent
plant. It is interesting to note that the larvae of most
species seek to avoid light by creeping into crevices in
the plant. At the end of about ten to fourteen days
these active larvas stttle down, and become fixed to the
host plant by means of the long thread-like proboscis
vhich is then buried dreply into the vegetable tissues;
the nourishing sap being drawn up bv this apparatus.
The creatures have now assumed the characteristicallv
" scale " mode of life, the white waxy powder which
has until now coated them disappears, and gradually
the mature condition is reached, and the cvcle begins
once more.

In different species there are, of course, minor dis-

similarities, but in these characteristic features many
species are alike. Some species, such as the currant
brown Lecanium, produce at least three broods of young
in the year.

Dactylopitis destructor or D. longiftUs will serve as an
example of mealy bugs. They are also easily
recognised, for they possess such distinctive charac-
teristics that there is no fear of ambiguity in identifica-
tion ; this is more particularly the case with
D. longiftlis, which is marked by the long white
posterior filaments in the female. The most common
species in our greenhouses is D. destructor. Though
they are such common and destructive insects, yet
there is very little literature to be found on the sub-
jects either of their life-history and habits, or morpho-
logy. However, it is known that they are very prolific,
the female of D. destructor laying usually from 400 to
600 eggs at a brood. They are embedded in a white
flocculose network of waxy threads, which cover the
eggs and quite effectually protect them from attacks of
other insects. The female feeds all the time she is
depositing her eggs, and the end finds her nothing more
than a little dry piece of dead skin, with the mass of
eggs behind her. Before egg-laying commences she
measures about 4mm. in length. In two or three
weeks the young hatch out of the eggs, and after a
day or two they leave the protection of the white floccu-
lent covering and begin to wander about actively.
They possess at this stage very conspicuous antennas
and legs, and are of a pale yellow colour. In one such
brood there may be a dozen males ; these soon separate
themselves from the rest to construct a special little
fluffy cocoon, from which, after two or three days, the
winged male emerges. It is provided with three pairs
of eyes, and lives but a very short time. D. longifilis
is not oviparous like D. destructor, but is viviparous.
It is a larger creature, but not so prolific, though it is
as general a feeder as the allied species. These pests
are very abundant in hothouses, where the artificial
conditions of relatively constant temperature, moisture,
and food supply give them a specially favourable en-
vironment, and their rate of production is consequently
very rapid.

America suffers even more from the ravages of
Coccidae than we do in this country ; perhaps its most
destructive insect is the -San Jose, or Pernicious scale
(Aspidictus pcrnkiosus). It is so widely disseminated,
and has become so firmly established in the principal
deciduous fruit regions of the United .States, that its
extermination is now, in most cases, out of the ques-
tion ; it is looked upon as a permanent factor to be
regularly dealt with. There are, of course, the pre-
ventive ;md quarantine measures against introducing it
into new regions on nursery stock, but once it has a
foothold the only certain method of destroying it is
the hercjic measure of digging up and burning all in-
fested trees. But orchards can be made profitable
even if the scale be there, by controlling its spread by
means of insecticides. The San Jose scale is found in
Japan, being apparently of recent origin ; probably it
came on .Vmerican fruit trees, chieflv from California,
where it has been longest established, and where its
ravages are most serious. But it is interesting to note
that in Japan the San Jose has met its match, in the
person of the little twice-stabbed ladybird beetle
(Chilocoriis similis). This beneficent little creature is the
enemy of Japan's destructive scale, Diaspis pcntagona,
and, fortunately, it has taken just as readily to the
introduced species, and very materially checks its in-
crease. {To be continued.)

Sept., 1904]

KNOWLEDGE >.\; SCIENTIEIC NEWS.

225

Microscopica.1 Table.

A correspondent, writing over the initals J. Q. T.
writes from Queensland Australia : — "At various times
I have seen in your columns descriptions of work-tables
for microscopy, and I venture, therefore, to send a
description of how I made my own. The top of my
table is made of half-inch pine, 36 inches by 16 inches,
and is raised on four legs 30 inches from the ground.
To make the table steady, I screwed on cross-pieces at
both back and front, and at the sides, as illustrated.
The lower front and back cross-pieces were 2 2i inches
from the upper cross-pieces, and upon these 1 screwed
two narrow boxes 22 J inches in height, 16 inches deep,
and 9 inches wide. To the front of these I .ittachcd
doors by means of i-inch hinges, and arranged a
simple wire hook to fasten them, though a small lock
or bolt would doubtless be preferable. The cupboards
thus constructed contain as much as possible of my
apparatus, excluding, of course, stock-bottles of re-
agents, etc., and are fitted with shelves in the follow-
ing way. In the left-hand cupboard there is only one
shelf for my objective jar (in this climate it is only safe
to keep object-glasses in an air-tight j;ir with calcium

....

- 36---

*r^^-5

(■ ifc >.

1 [

i - -I

;--q'-

«0

1 I

1 r

I ■ [

1 1

09T View

JsideVi'ew. L

turn-table, brushes, htittles of cement and varnish, etc.,
and so on. If work has to be left suddenly, a bell-jar
is placed (jver the niii-ros(-ope to protect it from dust.
To the front right-hand corner of the table is screwe<l a
piece of i inch pine, 2 inches wide and S inches deep,
so that 4 inches are on the t.-ililc and 4 inches pro-
ject ; to this is clamped a small microtome. Wlicn
using the table as a support for a photo-micrograpliic
camera it was found to vibrate unpleasantly, and this
I obviated by the following simple device. Eight
pieces of 2-inch wooti, each 4 inches square, were
taken, and in four of these holes were drilled to take
the feet of the table-legs, and they were then screwed
to the top of the other four pieces of wood with pieces
of rul)l)er between (1 made use of some old rubber tyre-
tubes). All tile bottles except those containing mount-
ing media are lilted with corks and rubber-capped
pipettes. I'o !.;i\i' the table a finished appearanci' I
stained it with the following mixture, which was re-
commended some years ago in the -American ' Journal
of .Applied Microscopy ' : (a) Copper sulphate, 25 parts ;
potassium chlorate, 25 parts ; water, 200 parts. Dis-
solve the salts in hot water, apply hot, and give a
second coat when the lirst is dry. Then apply (/')
aniline oil, 12 parts; hydroc-hloric acid, icS parts;
water, 100 [Kirls. This second solution must be ap-
plied cold. The power of the stain is much increased by
subsequent washing with hot soap-suds and water.
This stain gave a line black, which is not affected even
by nitric or sulphuric acid if they are C|uickly wiped
off. My water supply consists of a large bottle (con-
taining about 80 ozs.) placed on a shelf to the right of
and above my table. From this comes a siphon of
glass tube with rubber joints (rubber being perishable)
ending in a fine jet a few inches above the table rmd
closed by a clamp. The sink is a large enamelled
bucket to receive waste liquids, and there is a tin box
for waste paper, broken glass, etc."

Foot %uQt5l

^'°'b- Iconic

'rrrrrs-

Notes and Queries.

f^caatrjT jioQrd. \

chloride), immersion oil, and purely optical accessories.
In the space beneath I place the microscope itself in its
case. In the right-hand cupboard the shelves are much
more numerous, and are fitted so as to run in grooves.
The upper shelf contains the reagents. For this I took
a thick 2-inch board, pierced it with holes from one
inch to three inches diameter, and then screwed it on
top of a i-inch board as shown in the sketch. .'\t
one end T gouged out a groove 8 inches long, 3
inches wide, and i inch deep to serve as a useful
receptacle for section-lifters, brushes, etc., which
should be conveniently at hand. It should be noted
that the 2 inch holes in this shelf are the proper size
to hold Grubler's 100 cc. reagent bottles, which I have
found very useful. The bottles containing fixing,
staining, clearing, etc., fluids are placed each in its
proper hole, and on starting work the board is brought
out and placed on the table. The shelf below is
utilised to carry slips, cover-glasses, troughs for pond-
life, etc. In the next shelf are kept note-books, pens
and pencils, ink, paper, camera lucida, and other
accessories for recording observations ; below this a

Reversal of Image in Using Beale's Camera Lucida.

A correspondent writes : " In m.'tkinf; drawings of sections,
when it is desired to sketch in the outlines by using the camera
lucida and to put in the details freehand with direct vision,
Beale's reflector, with its jiartial reversal of the image is
notoriously awkward to work with, but its principal fault may
be counteracted by the following procedure, so far as work
with the lower powers is concerned. Put the slide upon the
stage upside down, i.e., with the cover-glass underneath, and
focus through the thick glas.s slip, sketch the rough outlines,
&c., of the section, then remove the reflector, reverse the slide
so as to focus through the cover-glass as usual, and with a
higher power if necessary, fill in the finer details frc^ehand,
using direct vision. Kach part of the section will thus be
found in its proper place in th(^ outline sketch. Care must
betaken not to knock the cover-glass sideways when removing
it. If the stage aperture is small, the slip can be supported
at the ends by pieces of glass." Another correspondent, Mr.
C. H. Caffyii, suggests drawing on a sheet of paper placed on
a piece of carbon or black-leaded paper, by which means the
outlines will be found reversed when the paper is turned over,
and can then be filled in without the use of the camera
lucida.

{Communications and enquiries on Microscopical matters are invited,
^ and should be addressed _[to /•'. Shillington Scales, '^Jersey," St.
IJarnal'iis h'mid, Cainlirnt^'e ]

226

KNOWLEDGE & SCIENTIFIC NEWS.

[Sept., 1904.

TKe Face of tKe Sky for
September.

By W. Shackleton, F.R.A.S.

The Sun. — On the ist the Sun rises at 5.14, and sets
at 6.46 ; on the 30th he rises at 6.0, and sets at 5.39.
The equation of time is zero on the ist.

Autumn commences at noon on the 23rd, when the
Sun enters the sign of Libra.

There is a total ecHpse of the Sun on the 9th, invisible
in Europe, the shadow path lying entirely over the
Pacific Ocean.

Sunspots, facuLT, and prominences are fairly numerous;
at the time of writing, three groups of spots, as well as
a considerable amount of faculae, are visible.

The positions of the spots, &c., with respect to the
equator and poles may be derived by employing the
following table : —

Date.

Axis inclined from N.
point.

Centre of disc, N of
Sun's equator.

Sept. I ..
II •■
21 .,

Oct. I ..

21° 19' E.
23° a'
25° 12'
26^ n' E.

7° 13'
7° 14'
7° 2'
6" 38'

The Moon :-

Date.

Phases.

H. M.

Sept. 3 ..

9 ••

.. iG ..

„ 24 ..

C Last Quarter
• New Moon
J First Quarter
0 Full Moon

2 59 a.m.
8 43 p.m.

3 13 pm-
5 50 P-m.

Sept. 9
.. 23

Perigee
Apogee

7 12 p.m.
6 o a.m.

OccuLTATioNS. — The Moon passes through the
Hyades about midnight of the 29th, when many of the
stars are occulted ; Aldebaran suffers occultation soon
after sunrise on the morning of the 30th.

The Planets. — Mercury is in inferior conjunction
with the Sun on the i6th, after which date he is a morn-
ing star in Leo.

Venus sets too soon after the Sun to be suitable for
observation.

Mars is a morning star on the confines of Cancer and
Leo, rising about 2.25 a.m. on the 15th.

Jupiter is the most conspicuous object in the sky, look-
ing nearly due E. about g p.m. On the 15th he rises at
7.15 p.m., and is on the meridian at 2.16 a.m. The
equatorial diameter of the planet on the 14th is 48"-4,
whilst the polar diameter is 3"-i smaller.

The planet is near the Moon on the e\-ening of the
26th.

The configurations of the satellites, as seen in an in-
verting telescope at 12.30 a.m., are as follows: —

The circle (O) represents Jupiter ; 0 signifies that the satellite is
on the disc ; 9 signifies that the satellite is behind the disc, or in
the shadow. The numbers are the numbers of the satellites.

Saturn is a very conspicuous object in the sky looking
S. about 10 p.m. ; he is on the meridian at 0.30 p.m. near
the middle of the month, and although rather low down
in the sky he well repays observation, for even with sinall
instruments the planet is a beautiful object. The polar
diameter of the ball is iy"-o, whilst the major and minor
axes of the outer ring are 42"'5 and ii"-/ respectively;
thus the ring plane is inclined to our line of vision at an
angle of 16", the northern surface being visible.

Uranus is on the meridian about 6 p.m. near the
middle of the month, hence the best time for observation
is immediately after sunset. He is practically stationary
throughout the month, and is situated about 12 minutes
W. of the star 4 S.Tgittarii.

Neptune does not rise until after midnight.

The Stars : —

At the beginning of the month, at 9 p.m., the following
constellations are to be observed: —

Zenith . Lyra, Cygnus.

South . Aquila, Delphinus, Aquarius, Capri-
cornus, Sagittarius; Serpens, Ophiuchus, and
Scorpio to the S.W.

East . Andromeda, Pegasus, Pisces, and Aries ;

Pleiades on horizon.

West . Hercules, Corona, Bootes.

North . Ursa Major, Ursa Minor ; N.E., Cassio-
peia and Perseus; .Auriga (CapcUa) low down.

Minima of Algol occur on the 6th at 9.53 p.m., 9th at
6.42 p.m., 26th at 11.36 p.m., and 2gth at 8.25 p.m.

Telescopic Objects: —

Double Stars :-— r Ursa- Majoris XHI.h 20'", N. 55° 26',
mags. 2, 4; separation I4"'4.

j- Aquarii XXII.'' 23™, S. o"-35', mags. 4, 4, separation
3"-2. Both components are yellowish.

fl Cygni XlX.h 27"^, N. 27° 45', mags. 3, 5 ; separation
34". The brighter component is yellow, the other blue;
very easy double in small telescopes with a power of 20.

Cluster (M 11) in Aquila or Antinous. K.A. iS" 46"
Dec. S. 6 23'. Very pretty object for 3 or 4 inch tele-
scope ; it is an easily resolvable fan-shaped cluster, with
an Sth magnitude star in apex and an open pair of the
same magnitude just outside it.

KDouiledge & Selentltie flems

A MONTHLY JOURNAL OF SCIENCL.

Conducted by MAJOR B. BADEN-POWELL and E. S. GREW, M.A.

Vol. I. No. 9.

[new series.]

OCTOBER, 1904.

r Entered at "|
LStationers' Hall.J

sixricNCic.

CO^T^^^'TS.~See Page VU.

Sna^ke Forms in the
ConstellaLtions

And on Babylonia.n Boundary
Stones.

By E. Wai.tf.k Maunder, F.R.A.S.

Amongst the spoil brout;;ht by various explorers from
Babylonia are a number of small sculptured stones,
commonly known as boundary stones or landmarks.
These are inscribed with texts in archaic Babylonian
and Assyrian characters, and record the transfer of
lands and estates, or grants and renewal of grants. But
besides the inscriptions, most of them carry a number
of figures sculptured in low relief. Some of these are
certainl)' astronomical; others are probably so. There
can be no mistake about such a figure as is seen in the
middle of the second row of the stone shown in the
accompanying photograph (see !• ig. 1). I he slab in
question was one found at Susa, whither it had been
taken from Babylonia, and contains the record of a
land grant by Mclishikhu, King of Babylon, n.c. 1200.
The stone itself is in the Museum of the Louvre. The
figure shows a " Capricorn " — that is, a goat with the
tail of a fish. On another stone, a representation of
Sagittarius has been found, in which not only is the
composite figure shown of the archer — half-man, half-
horse, drawing his bow to the head of the arrow — l^ut
the archer has a wing, stretched back exactly like the
flying cloak seen in the designs of our star atlases
to-day. .About composite figures of this definiteness
there can be no mistake ; they are obviously constella-
tional in origin.

The case is a little different with such forms ;is the
.scorpion, the bull, the dog, or the eagle, since these
forms are not specialised in the constellations ; but
their occurrence in such close connection with symbols
manifestly stellar, renders it probable that they are of
the same character. The argument with respect to the
scorpion — a form continually seen — is stronger. N'ot
only is the attitude of the scorpion always precisely
that of the /lodiacal animal, but a very fine boundary
stone of the reign of Xebuchadnezzar I., King cf
Babylon, date about n.c. 1120, shows, as well as a
.scorpion, a vigorous composite figure which appears
to have been formed by combining the symbols of the
three neighbouring constellations, Aquila, Sagittarius,
and Scorpio.

It is not surprising that the .serpent should be con-
spicuous amongst these sculptured forms ; it figures so

largely in pagan mythology that its absence would be
more surprising I ban lis presence. \'et here the posi-
lions assigned to (lir \arious serpent lornis are
pi'culiar, and seem to ine to bcir a niaiiilesl rclaliim to
the positions occupied by tlie \arioiis snakes .iiid
dragons of the celestial sphere.

.So far as 1 know, although it has ollen hmi noted
that Drat^o is coiled symmetrically alxjut the pole

Fig. 1. — Boundary'.stone in the l.ouvre.
* Approximate date, B.C. 1200.

{Front n I'hotO'jraph hij Mfx/TS. W. A. Mit'ueU.)

of the ecliptic, no astronomer has ever called attention
to the very remarkable po^itions occupied by two great
cnnstellatiens, Mydra .iiul Ser|)ens in the primitive
sphere. The reason of the oversight has been simply
that astronomers have been led astray as to the date of
the origin of the constellations by preconceived notions,
and have entirely neglected the evidence which the
stellar figiu'es themsehes supplied of their antiquity
and place of origin. .\s I ha\e had occasion to point
out in this magazine before, the area in the southern
heavens left untouched by any of the constellations
handed down to us by Aratus, is clear proof that the

228

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

work of primitive constellation-making was carri^'d out
on an organised plan, and came to a conclusion at a
definite epoch. The date of that conclusion was,
roughly speaking, 2700 or 2800 B.C. ; the place some-
where not far from Sj. Lat. 40°. For there, and there
only, did the portion of the heavens covered by the
traditional figures correspond precisely to that rising
at some time or other in the year above the Imrizon of
the place.

Fig. 2.— Circumpolar Constellations, B.C. 2685. Zenith of N. Lat.io^.

If we take a precessional globe, move the pole back
some 64° or 65" of precession, corresponding, say, to
about 2700 B.C., and adjust the globe for N. I^at. 40°
— in other words, set it to the time and place when the
constellation figures were first defined — what do we
find? First of all the Great Dragon (see Fig. 2) clearly
is arranged so as to link together the north pole of the
heavens and the north pole of the ecliptic. It is as
nearly as possible synunetrical with regard to the two ;
it occupies the very crown of the heavens. With the
single exception of the Lesser Rear which it almost sur-
rounds, Draco is the only constellation that never sets.

Next Hydra. Here we have an arrangement even
more striking. As Fig. 3 will show. Hydra at this
time lay right along the equator, extending over about
1050, or seven hours of Right Ascension. Thirdly,
.Serpens. As Fig. 4 will show, the snake carried by
Ophiuchus not only writhes itself for some distance
along the equator, but struggles upwards, straight
along the autumnal colurc, reaching and marking the
zenith by its head. It is scarcely conceivable that this
threefold arrangement, which is not suggested by any
natural grouping of the stars, should have been carried
out as a matter of pure accident. It must have been
intentional. l'"or some reason or other — possibly for
the simple one that a snake was the animal form that
best lent itself to such a purpose — the equator, the
colure, the zenith, and the poles were all marked out
by these serpentine or draconic forms. Possibly in this
striking but immistakable relation we may find an
explanation of the old myth that a total eclipse of either
sun or moon was caused by a dragon ; of the adoption
of the Dragon's Tail as the sign of the nodes of the
moon's orbit with the ecliptic ; and of the term

" draconic " or " draconitic " month for the period
taken by the moon to pass from the ascending node
round to the ascending node again. It may be noted
that in Fig. i in the second row of figures, just succeed-
ing the Capricorn, there is a little house or altar sur-
mounted by a symbol identical in form with the
Dragon's Tail symbol, which we use to-day for the
descending node.

l.?ut now let us turn to the boundary stones and see
where and how the serpents are presented to us there.
In Fig. 5, which is a photograph of No. 90,829 in the
British Museum, and shows another boundary stone of
The reign of Melishikhu, the dragon is seen on the
very top of the stone, coiled in an attitude much like
that of Draco of the sphere. In Fig. i, we find the
snake stretched out straight at the base of the stone
like Hydra along the equator. In Fig. 6 (No. 90,840
in the British Museum), \\e have the snake bent sharply
at right angles, lying partly, therefore, at the base of
the sculptures, and partly up the side, in an attitude
recalling that of Serpens along the equator and up the
colure. The snake in Fig. 7 (No. 90,835 in the British
Museum, of presumed date about iioo B.C.), rises
straight up the stone, and it is not certain whether we
should identify it with Hydra or with Serpens. But
the positions of the snakes or dragons in the first three
instances are sufficiently striking as to suggest that
some 1,500 years after the original designing of the
constellations, and when both colure .and equator had
mo\ed from their primitive positions, the tradition of
the original purpose of these serpentine figures still
remained.

There arc three symbols, \crv clearly seen on the

FiK. ?. — Equatorial Constellations, near the Summer Solstice,
B.C. 2085. Zenith of N. Lat. 40 .

boundary stone from the Louvre (Fig. i), and on the
actual stone No. 90,840, though partly hidden on the
photograph through the effect of foreshortening, which
are of very considerable interest. They are present,
though less distinctly seen, on the other two stones ;
indeed, with but one or two exceptions they are a
feature of all stones of the class. These are a crescent
moon " on its back," and two stars, usually of different
forms. The first is an eight-rayed star, the second a

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

circle containing a four-mycd star. These we know,
from actual inscriptions on some stones of the kinti, to
be the symbols of the patron deities oi the first two
months of the year ; the first month being- presided
over by the moon-god, the second by a pair of deities,
the " Heavenly Twins."

There is a special significance in both these symbols.
The -Accadian and .Assyrian \-ears were luni-solar, the
months being actual lunations, and twelve months
constituting a normal year. But since twelve months
are eleven d.iys short of a solar year,' a thirteenth
month must be intercalate'd about e\ery third year, or
the beginning of the year will quickly travel backwards
amongst the seasons. The Mahomedan year, which
consists of twelve lunar months, does this, and its fasts
and feasts bear no relation to the seasons. But the
.\ccadians evidently wished their year to conform ;is
closely as possible to the solar year, and the method
which they eniploycd to secure this result was both
simple and efficient. The first new moon of the year
was recognised by the presence near it in the evening
sky of a bright star, unquestionably at one time the
star Capella. It might happen that on the first even-
ing, when the thin crescent was perceived, it would be
close to Capella, and the two objects would set to-
gether. Twelve lunar months later the new moon
would be observed again, but these twelve months
being eleven days short of ;i complete solar year the
moon would be some ii° less advanced in longitude
than it was on the former occasion. But since the
moon's daily motion in longitude is about 13", the
moon and Capella would set nearly together on the
following evening — the second evening of the month.

Fig. 4.— Equatorial Constellation.s, near the Autumn Hquinox,
B.C. JfiX.";. Zenith of .N. l.at. 40

.At the end of another twelve months it would not he
until the third evening of the month that Capella ;md
the moon set together, and in a fourth year it would
probably be on the fourth evening. But this, again,
would involve that the two objects would set together
on the first evening of the following month, which

would, therefore, be the true first month of the year.

In other words, the third ye.ir, that is to say, any year
indicated by the setting together of the moon and

Capella on the third evening of the month, would be a
yt^ar thirteen months in Iciii^th ; ollur ve.ars would be of
twelve months.

If Capella were observed setting with the moon at
the beginning ol the first month, would there be ;niy
bright star seen with il :il llic beginning of the second
month? There would be two— Caslor and Pollux —
which would serve, should the evenings ol llu' first
month have been cloudy, to luniish just the same

r'n:- 5.— lioundary. stone, No. 00,820. in the British Museum.
Date, about 1200 B.C.

{From ft Phutorjraph hij Meanrn. W. A. Maiutill.)

indic.-ition as to whether the year would be an ordinary
cine or an intercalary one, that Capella had given in
the first month. There arc no bright stars suitably
placed to continue these indications for the succeeding
iniMiths of the ye:ir.

This method by which the new moon was praetic;illy
used as a pointer for determining the return of the sun
to a definite constellation at the end of the solar year,
is utterly unlike the methods which writers have sup-
posed the ancient astronomers were accustomed to use.
But we know from an existing inscription, that it was
actually employi-d ; it was eminently simple ; it re-
(|uired no instruments or star maps ; it may have been
in use long before the constellations were mapped out ;
;ind though rough, it was perfectly clficient, and would
give the mean length of the year with all the accuracy
that was then re(|uired. It had one drawback, which
the ancients could not have been expected to foresee.
The effect of precession would be to throw the be-
ginning of the year gradually later and later — roughly
speaking, by a day in every seventy years, and the
time no doubt came when it w.is noticed that the
seasons no longer bore their traditional relation to the

230

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

months of the year. With Capella, as the star of the
first month, the year would commence, on the average,
with the spring equinox about 2000 B.C. ; if Castor
aiul I'olhix were originally used for the first month ot
the year then the corresponding date would be
4000 B.C.

Now we can see the significance of this threclold
symbol, so often seen on votive slabs and boundary
stones — the moon " on its back " together with two
stars. It is simply a picture of the sunset sky of the
first evening of the first month of the year, some 6,000
years ago. The crescent is shown on her back, be-

Fig. (I.— Boundary •stone. No. 90,840, in the British Museum.
Date, about I loo B.C.

{From a I'holoijrapk hij Mv/isrg. W. A. MunselL)

cause then, on the first e\ening of the month nearest
the spring e(|uin(i\, she is more nearly in that attitude
than at any other time throughout the year.

I would suggest th.it these three figures, the simple
representation of wh.it .ill the primiti\e observers saw
year after year through many centuries in the evening
sky at the beginning of the first month, were handed
down througii long ti;idili(in .is emphatically the
symbols of the year ; but th.il in pidccss of time a cer-
tain change took place in the precise significance
attached to them. At some time between 40G0 B.C.
and 2000 B.C., men must h;ive recognised that the be-
ginning of the year was falling too "late. The obvious

remedy would be to shift that beginning by a single
month, where Capella would be ready precisely in the
right position to act as index star. Whilst Capella was
fulfilling this oflice it is probable that a separation was
made in the three symtaols. The crescent " on its
back " would be still the appropriate sign for the first
month of the year, but Castor and Pollux would now
indicate the second. When the months were assigned
to various deities the moon-god inevitably presided
over the month of which the sign was the crescent ;
and the deities of the two great lights, Tammuz and
Istar, would as naturally be associated with the pair of
stars. Later still, Istar mav ha\e been identified rather

102

90835
BOUNDARY STONE.
INSCRISED WITH A SERIES OP TEXTS
REFERRING TO THE OWNERSHIP OF
A CERTAIN ESTATE DURING THE REIGNS
OF NABO UKiN'APUl andNINIB KUDURUSUR,
KINGS or BABYLON. APOu-r B.C. lOOO. ;

Fig. 7.— Boundary-stone in the British Museum.

(From a Photograph by Messrs. »'. A. MamcU.)

with the planet Venus than with the moon, since the
latter was already symbolised in the first month, so
that -Signor .Schiaparelli's explanation of the three signs
may hold quite good for latter times. That it did not
hold go(xi in earlier times we may infer from the well-
known triumph.-il stele of Naram .Sin, in which the
twin stars are shown exactly similar in design, which
could hartlly lia\e been the case if at that time they
represented objects so dissimilar as the sun and the
planet X'enus.

[The photograplis of boundary stones from the Louvre pnd the
British Museum are reproduced by tlie kind permission of
Messrs W, .\. Mansell, of 405, Oxford Street, by whom they
were taken] .

Orr.. 1004.1

KNOWLEDGE & SCIENTIFIC NEWS.

231

III. TKe Influence of
Fvingi

For BslcI on OtKer Forms of Life.

Bv George Massee, F.L.S.

Fungi arc looked upon with a certain aniouiU of
justifiable suspicion by the majority of people, on ac-
count of their poisonous properties. Some kinds are
undoubtedly very poisonous, but the dangers attendant
on eating fungi have been much exaggerated. The
percentage of edible fungi, compared with the whole
number, excluding the microscopic forms, is mucii
greater than in the flowering plants.

A very considerable number of the cases of fungus
poisoning recorded annually are in reality not due to
having eaten poisonous fungi, and may be explained
as follows. In the country, when fungi are abundant,
they are frequently not used sparingly, in the sense of
a relish, but often constitute the greater portion, if not
the only dish for a hearty meal. If a meal of this
nature is accompanied or followed by the drinking of
alcoholic liquor, more especially spirits, the fungi eaten
coagulate and form an indigestible mass, which to say
the least causes much discomfort, and may become
serious. Strong tea acts in a similar manner to
alcohol. An oyster supper followed by a copious
supply of whisky would in most instances produce
similar unpleasant results.

Nevertheless all such instances are recorded as cases
of poisoning by fungi.

This is not the place to enter into an explanation of
the differences between edible and poisonous fungi; it
is, however, necessary to state that the old fables on
the subject, such as the separable skin of the cap, or
the blackening of a silver spoon when brought into
contact with the cooked fungus, are absolutely unre-
liable.

Above ninety per cent, of the cases of poisoning by
fungi, both in Europe and North America, is due to
partaking of one particular kind of fungus called the
" Death cup " (Agaricus flialloides). The popular
name is derived from the presence of a loose cup-like
sheath surrounding the base of the stem.

The presence of a cup at the base of the stem is not,
however, the hall-mark of all poisonous fungi; in fact,
some among the best known of edible fungi have a
similar cup, and it is the sum-total of characters pre-
sented by the " Death cup " that enables it to be re-
cognised with certainty.

The " Death cup " is very abundant in woods in
this country, but does not grow in open pastures like
the common mushroom. When full-grown, the cap
is slightly convex, smooth, and usually of a very pale
primrose colour ; the gills remain permanently white ;
the stem is from four to five inches in length, white,
and bearing a loose white collar some little distance
from the top ; the base is surrounded by ?. loose cup-
like sheath having a ragged edge.

Lack of space forbids entering into a detailed ac-
count of the numerous diseases caused to members of
the animal kingdom by fungi — " Thrush " (Oidium
albicans), appearing in the mouths of infants ; " ring-

worm " [Ac/iorion Schociilcnii), a disease which passes
from man to animals ; " Muscardine " {Botrylis
knsHimt) proves very destructive to silkworms. Men-
lion has already been made of the diseases of other
insects caused by fungi.

In speaking of fungi benelicial to other forms of life,
it was stated that wo bcnelited to the extent of
hundreds of millions of pounds sterling annually
through work done by fungi. On the other hand, it
is equally true that we annually lose at least an equal
amount, due to the injury caused by parasitic fungi.
In support of this statement, which, perhaps, might
be considered as improbable, it may be well to give
soMH- ollirial statements. The Prussian Statistics
lUneau announced a loss of ;£,2o,628, 147 on wheat.

The "Death. tup" Vun^uti lAi^nyUut iihuUuUh'i). Natural size.

rye, and oats grown in Prussia, caused by grain rust
during the year 1891. Wheat rust caused a loss of
;£.'2, 500,000 on the wheat harvest of 1890-91 in
Australia. In the year-book of the United States De-
partment of Agriculture for 1898 the loss of cultivated
crops caused by fungi for that year is estimated at
^40,000,000. A fungus disease called peach leaf-curl,
which proves very destructive to peach trees, does
injury to the extent of ^.600,000 annually in the
United States. No oflicial statements as to the
amount of injury done by fungi to cultivated crops are
issued in this country, but it is quite certain that we
suffer as much in this respect as other countries.
English cucumber growers suffered a loss of at least
^20,000 during the year T901, caused by the ravages
of a microscopic fungus parasite.

The question naturally suggested by the above state-
ments is. Can nothing be done to prevent, or at least
to reduce, such enormous losses? In answer it may be

232

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

stated that at the present day provisions are made in
almost every civilised country for studying fungus
diseases, and for imparting practical information on
the subject to farmers and horticulturists. In this
country the Board of Agriculture is the headquarters
in this' matter, aided by various colleges and societies.
.Svmbiosis or mutualism are terms expressing a con-
dition of things where parasite and host mutually bene-
fit by their u'nion. Lichens are the most pronounced
examples of this condition of things, and even here the
combination retains rriany of the characteristics of a
more pronounced type of parasitism, where the plant
attacked suffers from every point of view without any
compensating factor. For instance, the_ algal and
fungal constituents of a lichen each loses its own in-
dividuality, and is incapable of performing those
functions' which are natural to it as a free and in-
dependent entity.

:1J

The Hawthorn Cluster=cup Fungus. ( 1 1 The first condition parasitic on
a Juniper branch inatural size) ; (2I the second condition growing
on a living pear leaf (natural size).

In many other instances where a parasitic fungus
attacks a particular host plant, the latter is not killed,
but on the other hand the part attacked, which is
often sh.arply localised and modified, continues to grow
from year to year. This is very clearly seen in the
dense tufts of branches popularly known as " witches'
brooms " or " birds' nests," so common on many of
our forest and fruit trees.

Such developments, which are frequently of large
size and very conspicuous, present marked differences
in structure ;ind habit to the normal portion of the
tree on which they arc grdwing. I'Or instance, the
branches of "witches' brooms" .alwavs grow erect,
the leaves are feebly developed and almost destitute of
chlorophyll, and are hence incapable of assimilating
food ; finallv, such portions nexer bear flowers. Now,
from the above statement, it will ha\e been gathered
that such combinations of fungus and host plant are
incapable of furnishing themselves with food, and in
realitv lead in turn a parasitic life on the normal part of
Ihc tree of which thev form a portion.

It mav, perhaps, be well to state that not every
" bird's nest " seen in trees is caused by a fungus.
For example, the dense tufts so common in many birch
trees are caused by a very minute mite.

Allusion has already been made to the fact that
many fungi assume a very different appearance both in
form, size, and colour, during different periods of their
development. These contrasts are in many instances
so pronounced that the various phases of one and the
same fungus were at one time considered as entities or
distinct species, and allotted positions in the classifica-
tion of fungi widely separated from each other.

Loose smut of oats, V M tla'^o avfUir , (1) Ear of oats infected (natural size);
(2) spores of the fungus highly magnified) ; (3) spores germinating
and producing minute secondary spores (highly magnified).

Our knowledge at the present day that certain forms
are but links in the chain of one species depends on
what are termed pure cultures. This means that one
form or condition of a fungus, grown under condi-
tions which prevent the possibilit}' of contamination
from outside sources, eventually produces the second
condition ; while this, in turn, again gives origin to
the first condition.

As an illustration of a fungus appearing under two
remarkably different forms, and growing on different
plants during certain stages of its life-cycle, may be
mentioned the destructive parasite popularly known
as hawthorn cluster-cups. The first or spring condi-
tion, called Gvmno^porangium clavariafnrme, grows on
the common juniper tree, where it causes the infected
branches to assume a swollen or gouty appearance.
During the month of Mav these swollen portions be-
come covered with dull orange-coloured, gelatinous,
finger-like bodies about half an inch long. When
examined under the microscope, these orange gela-
tinous masses are seen to consist entirely of a ma.ss of

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

233

spores, each spore being divided liy a cross-wall into
two equal portions, and supported on a \ cry lon.i^
slender stalk. The mycelium of this condition of the
fungus is perennial ; that is, it remains living in the
infected jimiper branch from vear to year; consi'qucntly,
when a branch is once infected, the disease continues
to spread, the swelling continues to increase in size,
and a crop of spores is formed every spring. If the
orange masses of spores are carefully observed they
will be seen eventually to become covered with a
delicate whitish bloom, resembling in" appearance the
bloom on a plum or a grape. Examination under the
microscope shows that this apparent bloom consists in
reality of a mass of exceedingly minute spores, or, as
they are usually called, secondary-spores, produced by
the much larger prexiouslv formed orange spores.

These secondary-spores, which are produced in
enormous quantities, become free when mature, and
are distributed by wind, birds, insects, &c., and those
that happen to alight on the moist surface of young
leaves of pear trees, or on the voung shoots, Ic.ives, or
fruit of the hawthorn, germinate and enter the tissues
of the living plant, and in course of time produce the
second form of fruit, at one time considered as an
independent fungus, and called Rocsieliti. The spores
of this form are in turn dispersed b}' wind, &'c., and
those that alight on a juniper branch give origin
eventually to the form of fruit found only on juniper.

The feature to remember in the abo\e account is the
fact that the spores produced by the form of the fungus
growing on juniper cannot directly infect a juniper
again, but can only infect pear or h;iwthorn ; on the
other hand the spores produced on pear or hawthorn
cannot directly infect either of these pl.ints, but only a
juniper plant. The spores cannot infect any other
plant except the three mentioned.

The very injurious rust of wheat, Puccinia graminis,
which abounds wherever this cereal is cultivated, is a
fungus having four different forms or phases included
in its life-cycle. Two of these appear in the spring on
the young leaves of the common barberry, and less
frequently also on the fruit of this shrub. The first
condition to appear on the leaves, under the form of
minute, inconspicuous yellowish clusters of pimples, are
the spermogonia, structures of unknown functions, and
by some considered as aborted male organs. These
are quickly followed on the opposite side of the leaf by
clusters of minute, cup-shaped bodies with notched
edges, and filled with myriads of very minute golden
spores. The last mentioned stage of the fungus was
once considered to be an independent plant, and was
named Aecidinm bcrheridis. It is popularly known as
" cluster-cups," and is a very beautiful object when
examined with a pocket-lens, or under a low power of
the microscope. The spores produced in the cups are
scattered by wind or carried by various insects or
animals, and those that happen to alight on the voung
leaves of \vheat soon germinate and enter the tissues
of the ^vheat leaf, and after the space of a few days
rustv-orange streaks appear bursting through to the
surface of the leaf. These rusty streaks consist of
masses of spores belonging to the third condition of
the fungus, once called Vrcdn liueavis. The spores of
this form are produced in immense numbers and in
rapid succession throuirhout the summer months, and,
being scattered by the various atrents enumerated
above, it can be readily understood how quickly an
epidemic of rust can spread when a few wheat plants
in a field have once been infected.

During the autumn when the wheat is approaching
ni.ituritv, the devcloiiment of UrcJo spores ci-ases, and
a fourth form of spore, the last in the sequence of
(lexelopmcnt, appears on the Icaxi's of the wheat plant.
This is the Puccinia stage. These spores remain in a
dormant condition until the following sjiring, when
thev germinate .and produce \crv minute secondary-
spores which, w lien pl.iicd 011 a barberry leaf, give
origin again to the s[n'nnoi;oiii.i ,ind " cluslcr-cup "
conditions, and the cycle of dcvclopnienl commences
anew.

The " .Smuts " and " Hunts " are also very de-
structive to cereals, forming a dense mass of black
soot-like spores in the cars. Some species infesting
wheat ha\e a very unpleasant odour resembling de-
caying fish when rubbed between the fingers. The
life-historv of the .Smuts (Ui/ilago) is peculiar.

The minute bku-k spores are scattered by wind, and
remain in tlie soil unlil the following spring, when
they giM-minate, and the t;erm-tui3cs enter the tissues

'v»Jl^

rheconidial or first .stase of u fundus called sV/irnfiiim friirliiti-na, very
ciimmon on tile fruit of the apple, pear, plum, cherry, &c. It
causes tlie fruit to become dry and "mummified" (natural size).

of seedling cen'.iK. The fungus grows in the tis.sues
of the host-plant without doing any apparent injury
until the ear is formed, when the fungus develops in
the position normally occupied by the grain, and in
due time its mass of black, powdery spores bursts
through the tissues of its hosl-planl. In all cereals
except maize the fungus can only infect the plant
during the seedling stage. When a month old the
fungus mycelium can no longer enter the tissues.
Space prevents more than a passing allusion to the
numerous diseases caused by fungi to forest and fruit
trees. Larch trees, especially when grown in low
damp districts, suffer severely from a small and very
beautiful cup-shaped fungus, orange inside, _ snow-
white and minutely woolly on the outside. Fruit trees,
more especially apple, arc too often killed by a fungus
which destroys the bark and produces a cankered ap-
pearance, finally killing the branch attacked.

Neither are fruits exempt, the numerous _ blotches
and rotten patches on ripe fruit being in most instances
attributable to fungi.

234

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

Astronomy in the Old

Bv ^^liss ]\I. A. Orr.

The Jews were forbidden to study and forecast the
movements of the heavenly bodies, lest they should be
led away into star worship and star di\'ination. So says
the Talmud. Yet some knowledge of astronomy is neces-
sary to a nation, and especially to her priests; for only
by observation of the heavenly bodies can the dates of
festivals be accurately fixed. How far did this knowledge
extend with the Jews ?

Professor Schiaparelli, who has written learnedly and
sympathetically on ancient Greek astronomy, now essays
to answer this question, by studying the text of the Old
Testament, and comparing it with the best translations
and commentaries.'" The data are scanty, and unfortu-
nately just where we might expect to find light — namely
in the ancient Jewish calendar — we are in the dark. The
month was evidently lunar, from its Hebrew name, and
from the frequent mention of festivals of the new moon ;
the year was as clearly solar, since the three great yearly
religious festivals were all connected with the seasons.
But a solar j'ear does not contain a whole number of
lunar months, and the problem of bringing the two into
accord has taxed the skill, and tested the knowledge, of
primitive astronomers of all nations. W'e cannot be sure
how the Jews solved the problem. They counted twelve
months in their year, and no mention is made of extra
days or intercalated months. Some such device, however,
there must have been. Some writers assume that astro-
nomical observations were made, which would have been
the only exact guide. Professor Schiaparelli thinks, with
some others, that a thirteenth month was added whenever
it was apparent that the crops would not otherwise be ripe
in time for the offering of first-fruits, which was made on
the fifteenth day of the ist month. In this way direct
terrestrial observations of the seasons would be used to
correct a calendar founded on celestial phenomena. The
Jubilee period of 49 solar years is almost exactly equal
to 606 lunations, and this would have given a useful
cycle ; but there is no reason to think that it was used
for this purpose.

In connection with the custom of reckoning the day
from evening to evening, derived perhaps from the
method of beginning the month with the first appearance
of the crescent moon, Schiaparelli suggests an explana-
tion of the curious phrase " between the tv/o evenings."
(See marginal translation at Exodus xii. 6 and xxx. 8.)
The evening, he says, was divided into two parts, the
first beginning at sunset when it was still light enough
to work, the second at the moment when a crescent moon
would be visible, and ending when it had become quite
dark and all stars were visible. The second evening
would begin, on an average, half an hour after sunset,
and an hour before dark. This was the beginning of the
new day, and it was then that Aaron lighted the lamps
and burned incense.

How were night and day divided ? There is no word
for hour in Hebrew, but only in the dialects which took
its place in Palestine after the Exile. The word in the

* " L'Astronomia
(Milan : Hoepli.)

neir Antico Testamento, " G. Schiaparelli.

book of Daniel is Aramaic, and the expression " that
same hour" means merely "immediately." Much has
been written about the so-called dial of Ahaz. The fact
is, as Schiaparelli points out, that the word which in our
Authorised Version is given first as " degrees " and
then as "sun-dial" is in the Hebrew the same, and
means literally " steps." A glance at the marginal
notes will show that the rendering is a hypothesis
of the translators. Hezekiah, living about 700 B.C.,
may have possessed a sun-dial, brought from Baby-
lon or elsewhere, but there is no internal evidence
to prove that he had ; and it seems quite as
likely that the passage : " Behold, I will bring again the
shadow on the steps, which is gone down on the steps of
Ahaz, ten steps backward" refers to a flight of palace
steps which the sick king could see from his bed, and
that he marked the lapse of time by the creeping of the
shadow from step to step. If dials were used, there
would surely be some mention of divisions of the day
more exact than " in the heat of the day," " early in the
morning," &c.

The Hebrew week, with its seventh sacred day, Schia-
parelli thinks had no connection with the Babylonian
unlucky seventh day, since that was bound up with the
lunar month, while the former was an independent
period.

A few stars and constellations are mentioned in the
Old Testament, but it is sometimes difficult to know
which are meant. Most commentators agree that the
Kesil and Kimah of Job and Amos are Orion and the
Pleiades, but there is a curious passage in Isaiah : " The
stars of heaven and the Orions (Kesilim) thereof," which
the Authorised \'ersion renders "the constellations
thereof," and the \'ulgate " the glory of them." Probably
Orion is here put for any constellation, being bright and
well known. " The sweet influences of the Pleiades " is
a free rendering of a puzzling expression. No one knows
what was really meant by the " chains " or " delights "
of the Pleiades, for the literal meaning is one of these.
Some have thought it an allusion to the time of year in
which the Pleiades were visible ; Maury saw in it a
reference to Alcyone as the central sun of the universe !
To the present writer it seems that in this passage Job
is challenged to form or break up the constellations
which had been set in heaven by an immutable Divine
decree : " Canst thou bind the Pleiades into a cluster, or
scatter apart the stars of Orion ? "

The Authorised \'ersion translation of Arcturus in the
eighth and thirty-eighth chapters of Job is open to ques-
tion. It is more often thought to be Ursa Major ; but
Professor Schiaparelli gives weighty reasons, too many
to detail here, for believing it to be Aldebaran, and the
" sons of Aldebaran " the Hyades.

Less convincing, but ingenious, is the suggested ex-
planation of Job xxxvii., 9 : " Out of the Inner Chambers
comes the south wind, from Mezarim the cold." " The
Chambers of the South " are also mentioned in the ninth
chapter of Job among constellations, and Professor
Schiaparelli thinks that they were a Jewish constella-
tion, containing the brilliant stars of Argo and Centaur,
the inner chambers (= penetralia) of a house being where
jewels and precious things are kept. IMezarim should be
a northern constellation fo complete the antithesis : cor-
rect the reading to Mizrajim, the Threshing Flails, and
this aptly describes the forms of Ursa Major and Minor.
The Septuagint translates Mezarim as Arcturus, but
means (says Grotius) Arctos — i.e., Ursa Major. So old,
then is Shelley's mistake : — •

" Daisies, those pearled Arcturi of the earth,
" The constellated flower that never sets,"

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

235

Of the planets, there can be little doubt that \'enus is
named in the splendid apostrophe : " How art thou fallen
from heaven, O Helcl, Son of the morning ! " It has
been thought that X'enus and Jupiter were meant by the
Gad and Meni (" that troop " and " that number ") of
Isaiah Ixv., 2, but this is doubtful. If Kaivan, rather
than Chiun, is the correct reading of Amos v., 26, Saturn
is here intended, for that was his name among the
ancient Arabs and Syrians. The passage would read :
" Ye have taken Sakkuth your king, and Saturn, the
star of your God, images which ye have made for your-
selves."

The only other name in the Bible which is certainly
connected with stars is that of Mazzaroth. " Canst thou
bring forth Mazzaroth in his season ? " is asked of Job,
immediately after the mention of Orion and the Pleiades
quoted above. A name so nearly alike that it can hardly
fail to be the same thing occurs in one other place. In
the reform of Josiah, the burning of incense to " Baal, to
the Sun, and to the Moon, and to Mazzaloth, and to all
the host of heaven," was abolished. For etymological
and other reasons, Mazzaroth, or Mazzaloth, has been
variously translated as Lucifer, Sirius, Ursa Major, the
northern stars generally. Corona liorealis, Orion's belt,
the constellations of the Zodiac, the stations of the Moon,
the planets. Professor Schiaparelli, without venturing to
decide absolutely, favours the first, chiefly for the follow-
ing reasons : —

(i) A plural noun is used with a singular pronoim,
suggesting the dual nature of Venus as morning and
evening star.

(2) " In his season " indicates a periodical appearance
and disappearance.

(3) The position of the name in the sentence, coming
after Sun and Moon, but before all the host of heaven,
suggests a star inferior only to Sun and Moon in bright-
ness.

We may, however, be permitted to suggest tliat
Mazzaroth was perhaps superior to the host of heaven in
importance, not in brightness; and, if so, this argument,
as well as the two others, would apply equally well to
the constellations of the Zodiac. They are plural,
though the Zodiac is singular; and their chief feature is
periodical re-appearance.

But Professor Schiaparelli reminds us also of the three
constantly recurring symbols on Babylonian monuments,
which we know represent Sin, Samas, and Istar — that is,
Sun, Moon, and Venus. The "host of heaven," when it
means something more than simply the stars in general,
he regards as all the planetary and starry deities of the
Babylonian Pantheon, the " spirits of heaven."

The attempt to formulate a Hebrew cosmogony does
not appear to us altogether successful. It is difficult to
accept the view that, because Job speaks poetically of the
sky as " strong, and as a molten looking-glass," while in
a Psalm it is likened to a curtain, therefore the Hebrews
recognised two heavens, one above the other, the higher
containing the stars ; nor does it seem like serious criti-
cism to try to locate the " treasuries" of hail, snow, and
wind.

The truth is that the ancient Hebrews felt no intellec-
tual need, as did the Greeks, to construct world schemes
in order to explain natural phenomena. The universe
was to them, as Professor Schiaparelli himself observes,
simply the marvellous and inscrutable manifestation of
one supreme Power. It will doubtless be a surprise to
some to find that a whole book can be filled with the
astronomy of the Old Testament.

Photography.

Pure and Applied.

By CiiAi-MAN JoNiiH, I'M.C, P.C.S., iS:c.

Measuring Apparatus. — Photographic operations and
apparatus for their investigation are far from perfect
from a scientific point of view. There are no instru-
ments, so far, even if there are methods, that can fitly
be described as " standard," so that every investigator
who seriously devotes himself to the subject lias first
to examine experimental methods and then, generally,
to design the apparatus that he considers will prove
most suitable. There are a few fundamental matters
that too often do not receive the consideration that they
demand by reason of the general want of experience.
It is obvious that in all experimental methods it is
waste of trouble to eliminate a very small error while a
large error remains. It is very diflficult to enforce this
principle even in the most obvious cases, as, for ex-
ample, in the common case of weighing a measured
quantity of liquid. Here, if the smallest difference in
measurement is equal to a drop (say -02 gram), it is
useless to refine the method of weighing beyond about
a tenth of its weight (say 002). One may admit the
correctness of this principle, and yet easily fall into the
error of neglecting it, especially when the larger source
of error is not particularly obvious. It is sometimes
easier to see the mote than the beam. It seems to me
possible that Messrs. C. K. K. Mees and S. E.
Sheppard have made this kind of mistake in designing
the apparatus described in the next paragraph, and
this suggestion receives a certain amount of confirma-
tion by fhe fact that they refer to my opacity meter as
an opacity balance, and to the opacity balance that I
subsequently described as an " improved form " of the
earlier instrument. Neither of these two instruments is
an improved form of the other, they are distinct instru-
ments. The meter measures the opacity by comparing
the light that it transmits with the original light, and
the measurement is absolute in the sense that the
estimation depends only on the correct adjustment of
the meter, the observer's experimental ability, and the
opacity measured. The balance cannot do this at all.
It merely serves to comp.ire similar opacities on the
same plate, as, for example, in evaluating the results
of an experiment by means of a light-scale of known
value produced on the same plate. The meter, of
course, can do this also, but the balance serves this
one purpose better, being more convenient and more
.accurate for it th.an the meter. The balance will not
even serve to estimate opacities by comparing them
with a standard opacity scale, such as the circular
graduated screen (incorrectly called a sensitometer)
first produced by Mr. W.irnerke and now made by
Messrs. .S.ingcr .Shepherd and Co., because in the
opacity bal;ince the light transmitted that is scattered
is lost. The proportion of this scattered light is very
large, and I have shown it to vary between wide limits
according to the nature of the deposit in the film, and
to vary even in different opacities in the same plate.

Tlte Apparatus used by Messrs. Mees and Sheppard.—
In the current number (July) of the Journal of the
Royal Photographic Society, Messrs. C. R. K. Mees and
S. K. Shepp;ird describe the apparatus they use in their
photographic investigations, and which they intend for
use in "scientific photochemical research and plate-
making and testing." A machine for coating small
quantities of plates for experimental purposes has a

236

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

bed of plate glass supported on levelling screws, along
which is drawn at constant speed a piece of glass
covered with velvet on its under side and carrying the
plates to be coated. The trough that holds the emul-
sion is made of platinoid, it is surrounded with a large
hot-water bath, and to pass the emulsion to the plates
it has a slit below, that is made with great accuracy
and adjustable like a spectroscope slit. The trough is
7 cm. high and i cm. wide. I should have thought
that the alteration in level of the emulsion during the
coating would have caused a variation in the thickness
of the layer deposited, but there appears to be no
mention of this. As a constant light, the authors
employ a small area screened off from an acetylene
flame. 'J'o graduate the light, a rotating disc with
apertures in it of the ordinary kind is used, but it was
made with special accuracy and calibrated before use.
Much convenience and advantage results from enclosing
the disc in a case with an opening and grooves on one
side to take the slide that contains the plate, and a
camera-like extension on the other containing a flap-
shutter for starting and closing the exposure, cells for
colour screens, and a diaphragm. It need not be used
in a dark room. For developing the plates, which are
one inch or an inch and a half wide, a thermostat con-
taining about 10 gallons of water is used, with a
stirrer, and a regulator of the ordinary Reichart type,
the developer being contained in vertical glass tubes.
During development the plates are rotated in the tubes,
being suspended from vertical spindles for this purpose.
The authors appear to find that this movement is better
than a rocking movement with the plate horizontal, but
still not perfect. I should have thought that this
method would give a difference according to whether
the end of the plate with the longest exposure was
placed uppermost or otherwise, because at this end
there must be the greatest change in the developer,
and the vertical mixing effect produced by the regular
rotation of the plate on a vertical axis in a tubular
vessel must surely be very small. For measuring the
opacities the authors use a Hufner spcctro-photometer,
but with several nn)dilications to fit it for this particu-
lar work. I may be mistaken, but I cannot find from
the description that the difficulty of the scattered light
is met in any way. It is easy to measure something,
and with considerable accuracy, but if the something
measured is indefinite the results cannot be very
valuable. It is better to sacrifice a little accuracy if
necessary for the sake of knowing exactly what is
being dealt with. Perhaps the authors have taken
more precautions than are obvious for their descrip-
tion. Regarding the apparatus as a whole, it appears
to me that it presents many points of advantage that
future workers will profit by, but I am convinced that
there are many matters that need investigation before
the results obtained in working with it can be accepted
without qualification. I have sought only to give a
general idea of the apparatus ; those interested will, of
course, refer to the original paper.

A iXc/ta-nlis/'s Camera. — The possibility of getting
good typical photographs of living things has been
amply demonstrated during the la"st few years, and
many photogra|)hers ha\e dcx'oted themselves to this
kind_of work. That results of the first quality can be
obtained with an ordinary camera when supplemented
by home-made contrivances, has been shown by the
brothers Kearton ; but the methods which thev follow
are possible for only a very few and appreciated by
still fewer. Hence the demand for special facilities.
One of the most recent cameras that has been devised

to meet this demand is the " Birdland " camera de-
signed by Mr. Oliver G. Pike and constructed by
JNIessrs. Sanders and Crowhurst. It is a hand camera,
for Mr. Pike's method of work is to follow the bird he
wishes to photograph, focussing it meanwhile with one
hand upon the full-size reflex finder, and to release the
shutter with the other hand as soon as the bird is in
the desired position. The well-known Anschutz focal
plane shutter is made to form a part of the camera,
and an especial part of the apparatus is the connection
of this with the mirror of the finder so that when the
release is actuated the mirror moves out of the way
immediately before the opening in the blind passes
across the plate. The whole movement follows so
quickly on the touch of the trigger that there is no
sensible interval, nor is there any jar or noticeable
noise. The camera has many conveniences, the chief
of which are a mirror in the finder hood, so that the
image can be observed and focussed with the camera
level with the eye, and the possibility of opening the
front and drawing the lens forward, as shown in the
figure, to allow of one combination of the doublet, or
a lens of greater focal length, being used. The sensi-

tive material is carried in double backs, changing
boxes, or roller slides. A camera of this kind is, of
course, eminently suitable for almost any work in
which a moving object has to be photographed at a
critical moment, and that this particular instrument
serxes the purpose well is abundantly demonstrated by
the photographs obtained by its aid by Mr. Pike him-
self and by Mr. F. Martin Duncan. A small selection
of these is reproduced in the pamphlet describing the
camera, which can be obtained on application to the
makers.

The Scintilloscope.

One of the small defects of the cleverly-devised instru-
ments for displaying the scintillations which are produced by
the bombardment of radium is. that the speck of radium is
placed on a tiny pointer, which is between the spectator's eye
and the screen of pitchblende or other material that is bom-
barded. Consequently, the pointer partly obscures the effects.
In a little instrument sent to us, and called
(dew's " Scintilloscope." the defect is reme-
died in an ingenious way. The instrument
is in two parts, one part of which is the usual
magnifying lens. The other part, detach-
able, is a double screen. The upper part of
the screen is a thin plate of pitchblende polo-
nium, or thorium, all of which are extremely
sensitive to the impact of the "alpha"
rays that proceed from a radio-active material.
The lower or underneath part of the screen consists of a plate
coated with some such material. The alpha rays strike
upward, and produce scintillations of great brilliancy on the
pitchblende or polonium above. The instrument is fitted with
one, two, or three screens, and the difference in the effects
produced is very interesting.

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

237

Sunspot VoLriaLtion in
Latitvide.

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

In his letter, under the above title, in the August num-
ber of this journal Dr. Lockyer complains that I-ather
Cortie and myself have misunderstood, the meanint; of
the term " spot-activity track " which he has
originated. I think this complaint has no justification
in fact. Certainly, for myself, I did not suppose that
he intended the term to apply to the proper motion of
any individual spot, but it is abundantly clear that he
did intend to intimate by it that the spots were
gathered together in certain districts or regions,
separated from each other by broad barren intervals,
and that these districts, rich in spots, moved continu-
ously downwards towards the equator ; so that the
entire " eleven-year period " was the summation of
three, four, or five separate and distinct shorter cycles
cf activity. Dr. Lockyer himself applies the term
" zone " to these districts ; he has drawn them in his
diagrams as distinct, widely separated, areas, each
one moving continuously towards the equator ; and his
descriptions of them perfectly accord with his dia-
grams. He writes : —

" From sunspot minimum to minimum there are
three, but generally four distinct ' spot-activity
tracks,' or loci of movements of the centres of
action of spot disturbance." (Proc. R. S., Vol.
LX.XIIL, p. 147.)
Again : —

" These ' spot-activity tracks ' have possibly a
terrestrial equivalent in the variations from year
to year of the positions of the ' Zugstrassen ' or
cyclone tracks of Kiippen, it having been found
that cyclones in general, which move in the
direction of the great mass of air carried by
primary currents, have a strong tendency to
pursue somewhat the same tracks according to
the place of origin." (Ibid, p. 147.)
Vet again : —

" .Spoerer's Law of .Spot Zones is only annroxi-
mately true, and gives only a very general idea
of sunspot circulation. Spoerer's curves are the
integrated result of two, three, and sometimes
four ' spot-activity track ' curves, each of the
latter falling nearly continuously in latitude."
(Ibid, p. 152.)
Again, speaking at the Royal Astronomical Society,
on 1903, May 8, Dr. Lockyer said : —

" The general idea about the spot zones is that
spots begin in a zone in high latitudes (about
+ 30° to + 35°), and this zone gradually ap-
proaches the equator until the spots vanish
about latitude ± 5", the new cycle commencing
again in + 35". \ow a glance at this diagram*
shows that this is far from correct, because
sometimes there are two, and occasionally three
spot zones in existence in one hemisphere at r)nc
moment. Take the case of the year 1893, when
you have three zones. The curves of .Spoerer
are, therefore, very misleading, for by taking
the mean position of several spot zones you
arrive at a latitude in which spots may not exist
at all." (Observatory, 1903, June, p. 236.)

•The diagram of my paper communicated to the Society at this
meeting, 1903, May 8

It was because these descriptions answered to no-
thing on the sun that I communicated a " Note on the
Distribution of .Sunspots in 1 leliographic Latitude"
to the Royal Astronomical -Society at its last meeting.
I explained therein the nature of the mistake which
Dr. Lockyer had made with regard to the maxima on
w hich he based his paper, and that his method of join-
ing them up so as to show apparent fines of drift was
not only purely arbitrary, but was often against very
distinct and positive evidence.

Is Dr. Lockyer 's statement that his " spol-aclivity
tracks " " are not tracks on the solar disc," and that
his paper, read before the Royal .Society in 1904,
I'ebruary 11, has been "misunderstood," intended as
a uillulrawal of these descriptions and detinitions of
" spot-activity tracks " which I have quoted — in fact,
of all the main body of his paper? If so, I think it
was a pity to publish in " Knowledge and .Scientiiic
News " a diagram to explain how he had been led to
take up a position which he now finds to be untenable.
Dr. Lockyer objects to the note on p. 159 in this
journal for July, and claims that I'^ather Cortie rather
corroborated than opposed his result. I do not so
read Father Cortie's paper. His words are : —

" These facts, however, as to the persistence of
the disturbance in definite regions at some
epochs, and dearth of spots at others, do not
lend much countenance to the view of the varia-
tion in latitude being affected by a series of
' spot-activity tracks.' " (Monthly Notices, Vol.
L.\IV., p. 766.)
The last two sentences in Dr. Lockyer's letter form
a claim wiiich ought not to have been made. He says :
" I pointed out, as one of the main results of my
investigation, that outbursts of spots in high lati-
tudes are not restricted simply to the epochs at
or about a sunspot minimum, but occur even up
to the time of sunspot maximum." (" Know-
ledge & Scientific News," 1904, August, p. 182).
Dr. Lockyer's "investigation," so far as it relates
to the years 1874-1902, consisted solely in taking the
results of my p.iper, prepared by the desire of the
.\stronomer Royal for the Royal Astronomical Society,
1903, May 8, and adding the figures there given, in sets
of ten, of five, and of three. A computer of average
skill would do this easily in a couple of hours. But the
effect of this treatment would not be to bring out the
fact to which he alludes, but rather to obscure it. He
found the fact ready to his hand, explicitly set forth in
three-fold fashion in this paper of mine upon which he
was avowedly working. It was set forth in the dia-
gr.'ims, in the numerical tables, and in the brief pre-
liminary text. The latter ran thus : —

" -Spots in a higher latitude than 33° were at all
times rare, and when seen were never large or
long-lived. Taking them as a class by them-
selves they were seen irregularly, appearing ;it
times which did not seem to bear any fixed rela-
tion to any one of the four chief stages of the
sunspot cycle — minimum, increase, maximum,
and decline. Omitting these spots in very high
latitudes— a term which would cover a zone 10''
wide in each hemisphere, from 33° to 42°, for
no spots were observed in a latitude greater than
420 — the years of maximum, 1883 and 1893,
showed spots in practically every latitude be-
tween 30" north and 30° south, and they were
numerous from about 8" to 240 in both hemi-
spheres." (Monthly Notices, Vol. LXIII,
P- 4-S2-)

238

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

A New Depacrture in
Nactvire Printing.

By T. E. James.

The production of impressions of leaves, ferns, lace,
feathers, or other natural and artificial objects by
methods adapted to illustrate their outlines and sur-

Fig. I. — Blackberry Leaf.

face features, has long engayed the attention of ex-
perimentalists. The records of old attempts in these
directions are, indeed, of singular interest. They point
to extraordinary industry on the part of workers in the
art, though this frequently outstripped manipulative
skill, a circumstance, perhaps, not to be wondered at,
considering the means at hand, and the operative
difficulties.

We read of an observer who, in i()50, obtained nature-
prints of the dried leaves of plants by the aid of sooty
depositions. When the leaves were placed between
paper and carefully rubbed over, the adherent smoki-
ness was transferred, leaving a pictorial representa-
tion of the objects. Prof. Kniphof, of the University
of Erfurt, published at Halle, 1757-61, his " Herbarium
\'ivum," a curious work in twelve folio volimies, which
contained no fewer than twelve hundred printed plates
of natural impressions. A single plant specimen is
depicted on each plate, in many cases portraying its
whole aspect, all the ex.imples Ijeing hand-coloured.
The title-pages carry a border of plants, introduced
for ornamental purposes; and on some of these appear
butterflies in brilliant natural hues. It seems that
printer's ink was used to obtain the initial impression,
combined with pressure on the object. Kyhl, of Copen-
hagen, was also engaged in 1833 '" inventive methods.
He describes his process thus : — " As a correct copv
of the productions of Nature and .'\rt must be of great
importance, I submit a method I have discovered,

whereby copies of most objects can be taken, impressed
into metal plates, which enables the naturalist and
botanist to get representations of leaves, scales, etc.,
in a quick and easy way; these copies will give all the
natural lineaments with their most raised or sunken
veins and fibres; and the artist can, by means of this
invention, make use of Nature's real peculiarities; while
the merchant can produce patterns of delicately-woven
or figured stuffs, laces, ribbons, and so forth." Sub-
sequently, in 1851, Dr. Branson communicated to the
Society of Arts his views on the practicability of
adopting the electrotype process for the accurate re-
production of original impressions, when the latter
were taken in gutta percha. This marked a long
stride in advance, and following it, came the
adoption of lead as a mould, coupled still with the
electrotype system of casting a durable copy. At this
stage, Worring, of Vienna, made many notable im-
provements, which led to important practical results.
In 1S59, appeared the nature-printed " Ferns of Great
Britain and Ireland " (Bradbury), and, in 1859-60,
Johnstone and Croall's " Nature-Printed British Sea-
weeds." Mention should also be made of a paper in the
X'ienna Dcnkschripcn, in 1894, which was illustrated
by nature-printed plates of beech leaves, in sepia
monochrome.

The ingenious " Physiotype " reproducing system,
now being brought to notice, is due to the inventi\ e skill
of Mr. Francis Sheridan, who has patented the process.
In this, inks or other fixing media are superseded,
the novelty of the method consisting in the use of a
fine powder, the chemical action of which is responsi-
ble for the fac-simile. The modus operandi, as carried
out by Mr. Sheridan, is exceedingly simple. An object

Fig. 2.— Leaf of Woundwort.

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

239

T ',,

P ^-"^.m^.

■k

Figs. 3-4. — " Physiotype " Impressions of the Poppy and Foxglove (natural size}.

240

KNOWLEDGE & SCIENTIFIC NEWS.

[(_)CT., 1904.

for reproduction is placed upon white paper, and suit-
able pressure is applied by the hand or other means.
The operation leaves no visible trace of ;ui impression,
nevertheless, when a small quantity of the powder is
lii^htlv passed over the paper, an impression appears
on the surface, delineated as a print in the style of our
illustrations. Each is absolutely permanent. The
author claims a wide rang-e of application for his pro-
cess in nature-printing:, and printing: by contact. Its
adaptability for the rapid production of impressions of
the thumb and finger, of the palm of the hand, or sole
of the foot, may be very readily demonstrated, and
strictly " while you wait." Representations of flowers.

Fig. 5.— Oak Leaf.

leaves, grasses, ferns, wood sections, and similar
natural objects are also within its province ; as well as
fac-similes of lace and other patterns, and the designs
on coins and medals. One of the advantages of the
" Physiotype " print is tliat it can be used as an
artist's lithograph and transferred to stone, zinc, or
a'.uminium. By this means it is possible to print off
any number of impressions, and to produce them, if
required, in one or several shades of colour.

The precise applicability of " Physiotype " records,
and the development of the process as a nature-print-
ing method need not be discussed here. But,
if we may say so, it would certainly appear
to provide a welcome auxiliary to the teaching of
botany in tlie field. The production of a self-picture of
the leaves, fruit, or other parts of a freshly-gathered
plant is readily obtainable by its means, and the results

arc of a decidedly attractive and instructive character. As
an adjunct to the pursuit of " Nature Study,'' it should
prove of great value in stimulating the latent observa-
tional faculty of children. With the interesting pro-
spect before them of producing a pictorial fac-simile of
a living leaf, flower, or section, boys and girls might

Fijj. 0. — Impression of a Section of Wood.

be the more easily persuaded to collect material from
the countryside. For example, a series of leaves might
be brought together illustrative of their composite
qualities of structure, that is to say, of contour, vena-
tion, serration, difference between upper and lower side,
and so forth. The teacher would apply the lesson. Our
photographs from "Physiotype" impressions of leaves
(figs. I, 2 and 5) demonstrate the point. Again, entire
specimens of plants are susceptible of teaching effort,
where the mode of inflorescence is noted, form of
bud and corolla, attachment of anthers, the presence
of stipules, hairs, and other characters of growth.

Fig. 7. — Finjrer Prints showing: Whorls (reduced).

Some examples of common plants in flower at the
time of writing: were gathered and submitted to the
" Physiotype ' process. Each was essentially a living
specimen, and no more was done in preliminary
manipul.ition than to use such slight pressure as would
ensure the flatting down of the plant in a natural

Oct., 1904.]

KNOWLEDGE & SCIENTIEIC NEWS.

241

position before laying; it upon the white paper which
was to receive tlie invisible impression. Our ilhis-
trations (figs. 3-4) are of the poppy and foxglove.
With practice, no doubt, it would be possil)le to ob-
tain even better results than are here given. Still tht'v
very fairly represent the outcome of a pro\ ision.il trial
to secure the reproducticMi of living plants.

Fig. 8. — Ifnlargement of a Rolled Flnger = print.

Wood sections are well adapted for fac-simile.
Fig. 6 is from a sample kindlv lent bv Dr. Russell,
F.R.S.

The final illustrations (figs. 7-8) demonstrate fingei
printing.

On all grounds .Mr. Sheridan deserves to be con-
gratulated on what we must recognise to be an
exceedingly interesting development in nature-printing.

Birkbeck College.

The new session of Birkbeck College, which l)egins on
Monday, October 3rd, will be opened by an address delivered
by Dr. Mackenzie on " The Influence of Pure Science on
Progress." Among those who will deliver lectures or
addresses on the Wednesday evenings during the coming
session are the Dean of Ely, Colonel Sir 'J'honias Holdich,
Sir Robert Ball, and the Kev. J. M. Bacon. From the calen-
dar of the session 1904-1905, which comprises the usual day
and night classes for the preparation of candidates who enter
for the preliminary, intermediate and final examinations for
the London University Degrees in Science and Arts, we learn
that during the first term last year the class entries were,
evening, 3i6f); day, 5.S2. During the year sixty-four students
passed examinations of the University of London (seven with
honours), while other distinctions — scholarships, exhibitions,
prizes, certificates, and medals -were gained at the examina-
tions of various boards and societies : twelve students were
successful in the examinations for Assistant Surveyor of Taxes,
ten gained appointments as Assistant Examiners in the Patent
Office,andothersobtainedgoodappointments in other branches
of the Civil Service. Beyond this testimony to the practical
service of the " Birkbeck " to the persevering student, other
testimony must be borne to the excellent work it is doing in
spreading the systematic practical knowledge of science
among its widely distributed constituency.

ASTRONOMICAL.

ij^ical ( )l>ser\alory,

vard

ns, iiisll-tifnViilQp

Mr. A. Law',

WJts)Jv^-

one at the tilt:

AnnaLls of the Harvard College
Observatory.

Two contributions have recently been issued under the aus-
])ices of Harvard College. The first of these is the volume for
1901 and 1902 of the I?lue Hill M
and the expense of its public;iAjljn oiiiy
College, all the expenses of thealfcervyig stat
and investigations being borni^oy t'fifllljj/
rence Rotcli. In addition to ni.iint.iroiiig tl
tions -ind automatic records at three station^
Hill Observ.itory itself, a second -ftLJhc lia&^fyfa^^ (irelt
Blue Hill, and a third at the Neponsel^.flliiy-^rs^'eral inves-
tigations were undertaken, chief amongst which *.aP(ft<.'lE^-
ploration of the air with kites. Mr. Rotch is the American
member of the International Conmiittee for Scientific Aero-
nautics, and as far as possible flew his kites on the specified
international days, and when flights were not made on these
days, it was due to lack of wind at the ground, as a velocity
of at least six metres per second is required. If it is desired
to certainly fly a kite on any particular day, Mr. Rotch advises
the instalment of the apparatus on a steamer, which by creating
a wind through its motion will enable a sufficient current of
air to raise the kite. He advises by this means an investiga-
tion of the meteorological conditions above the trade- wind and
doldrums. Other investigations have also been conducted on
the audibility under various weather conditions, at Blue Hill ;
of the effect of weather conditions on the optical refraction of
the lower atmospheric strata ; and of the electrification of the
air and the quantity of carbon dioxide contained in it. These
last measurements seem to indicate that there are two maxima
of potential during the day, which are not always well defined,
and sometimes merge into one, occurring about noon or a little
before, and in the majority of cases there is a steady fall of
potential from about z p.m. until late in the evening, when the
electrification seems to reach a constant and low value.

The second contribution from Harvard College is the
determination by Mr. W'inslow Upton, during the year 1896-97,
of the position of the Arequipa station in Peru. Briefly it
results : —

Latitude, — 16' 22' 28-0".

Longitude, 4h. 46m. ii'73S. west of Greenwich.

Height above sea-level, 2451 -4 metres — 8043 feet.
Harvard College itself issues its circular (No. 74) on variable
stars of long period, and urges that in such cases it is useless
for observers to employ Argelander's exact method of
sequences. As it is, when the measures made at different
observatories on the same night are comp.ired, they often
differ by half a magnitude or more, owing chiefly to the red
colour of most of the long-period stars. The resulting
magnitudes would be nearly as good if the observer would
merely state that the variable was surely brighter than one
star and fainter than that next it in the sequence, without
attempting to estimate grades. Considering the large number
of variables of which we have no current observations, our
knowledge of their variations could thus be greatly and easily
increased.

» * »

Bulletins of the Lowell Observatory.

A numlier of interesting bulletins (Nos. 9-13) have arrived
from the Lowell Observatory, and indicate the varied and
valuable researches that are carried on there. In No. g Mr.
Lowell gives a new determination of the position of the axis of
rotation of Mars, championing the direct and observational

242

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

method aa u.-ud by Schuiparelli, rather than the direct method
used by Struve, of the calculation from the nodal or absidal
precession of its satellites' planes. Incidentally Mr. Lowell
points out that there is a strong discordance between the
results of Schiaparelli and Struve. Mr. Lowell's own results
are as follows : —

Position upon the Earth's

Equator 315" 32'. R.A., 54' 51' Dec.

Intersection of Martian
Equator and Martian

EcHptic 85' 56'. 24'' 32'.

Inclination of Martian

Equator to Ecliptic . . 22 55'.

In No. II Mr. V. M. Slipher gives a list of five stars which
he suspects to be spectroscopic binaries. These are .Alpha
Androniedie, .Alpha Librs, Sigma Scorpii, X Sagittarii, and
Epsilon Capricorni.

In No. 12. on " The Cartouches of the Canals of Mars," Mr.
Lowell restates his conclusions : (i) The canals develop down
the latitudes after the melting of the polar cap, the develop-
ment proceeding across the equator into the planet's other
hemisphere ; and they do this alternately from either pole.

(2) The canals are from their behaviour inferably vegetal.

(3) They are of artificial construction.

In No. 13 Mr. Slipher gives plates and details of the spectra
of Neptune and Uranus. He notes that he finds indications
that free hydrogen is very plentiful in the atmosphere of
Neptune, and is abundant on Uranus, but not so much so as
on Neptune. He also considers that some unknown light
gases related to hydrogen and helium might also be present and
account for certain unknown bands. Helium he could not
observe with certainty owing to the insensitiveness of his
isochromatic plates in the D region of the spectrum.

In one matter astronomers certainly owe a debt to Mr.
Lowell — namely, for his introduction of new words — words
that are at least new to the very limited astronomical vocabu-
lary. The expression " cartouches " is a case in point ; and
another is oft'ered by bulletin No. 9, where he says that "for
direct handling of the subject the planet's polar caps offer the
most trustworthy ' helves.'" We scarcely think the use of the
terms "expurgated" and "unexpurgated" in the same bulletin
so happy. They suggest Mr. Bowdler, and that Mr. Lowell's
bulletins are unsuitable reading for the young person.

* * *

The Royal Astronomical Society of
Canada.

The Astronomical and I'liysical Society of Toronto has
been accorded the above new title, and has just issued its
selected papers and proceedings for 1902 and 1903, which
prove very interesting reading. The President's address for
1903 reviewed the recent researches in cosmical physics. Mr.
\V. H. S. Monck gives a valuable catalogue of aerolites, and
Mr. .Arthur Harvey follow's it by a paper on " Shooting Stars
and UranoUths,"with special reference to the Mazapil (Mexico)
meteorite. He supplements Mr. Monck's catalogue, and con-
cludes that "aerolites are evenly distributed throughout space
and move at various angles with the plane of the ecliptic," so
that there is no evidence to show that there are drifting clouds
of matter in space which might be the exciting cause of solar
and our own magnetic disturbances. A second paper by Mr.
Harvey is practically a continuation of the same subjects, and
is called the " Vagaries of the Mariner's Compass." In this is
passed in review the researches which have been variously
carried on both in terrestrial magnetism, on auroral displays,
and on the solar work at the Greenwich and Yerkes observa-
tories. The final paper is on " Women's Work in Astronomy,"
by Miss ICIsie Dent. This is a most disappointing one ; it is
undiscriminating and full of errors. What is most striking is
the number of omissions of the names of American women
astronomers. The writer places both Mademoiselle Klumpke
and Madame Flammarion at the Paris Observatory, and she
places Lady Huggins in the same rank as the last named, both
as deriving their astronomical rank solely from their husbands'
position — a gross injustice to Lady Huggins. Miss Dent is
unaware that Miss Klumpke left the Paris Observatory some
three years ago to marry Dr. Isaac Roberts. She describes
Miss Elizabeth Brown as having been sent to Russia in 18S7
to observe the Total Solar ICclipse of that year by the British
Astronomical Association, which was not in existence until
three years later.

Meteoric Observation.

Mr. W. F. Denning writes from Bristol : —

" Perhaps more mistakes have been made in this department
than in any other field of astronomy. Certainly some of the
observations have been very wild, and more obviously calcu-
lated to excite ridicule than to win confidence. In this, as in
other branches of observation, it would have been better had
certain observers never essayed to do anything, since their
results are affected by personal equation or individual idiosyn-
crasies of such marked character that their work rather
damages than benefits the cause. There is no doubt that the
majority of the radiants hitherto determined are useless, being
either pseudo positions or so inaccurate that their elimination
is desiralile. Their retention and combination with correct
radiants have the effect of detracting from the value of the latter.

" To attempt to detail the errors made in this branch would
serve no useful purpose, and it would occupy a large amount
of space. One observer, a few years ago, watched the Per-
seids, and saw the meteors shooting not from the radiant, but
towards it. Numbers of meteors were recorded in Camelo-
pardus and surrounding constellations, but all of them were
dashing towards the radiant !

" Another observer noted that many Perseids, after traver-
sing their paths, made return journeys along the same paths.
He also saw many large cloud-like meteors, and the sky
produced flashings, coruscations, &C., which he attributed to
meteoric action.

" Other observers frequently record meteors whose paths
are suddenly bent or crooked. Others, again, frequently note
curved paths, and some observers see meteors which sud-
denly stop and shoot back nearly in an opposite direction.

■• Practice, experience, and care will not always form a good
observer. The most essential quality is self-aptitude or natural
capacity which varies greatly in different individuals. Meteoric
observers, like poets, are born, not made. Education can never
ensure very high proficiency unless the learner possesses
inherent qualities which materially help him to acquire it.

" .As far as m\" experience goes, there have been observers
whose radiants cannot be relied on to within lO' ; there have
been others whose positions can be depended upon to within
2° or 3°. Unfortunately it is often impossible to certainly
single out the good from the indifferent positions, and so our
accumulated results form a curious medley of precise and
pseudo results. Though this is undoubtedly the case, however,
we know the correct radiants of a considerable number of
showers.

" F"ortunately we have many reliable observers working
to-day at this department, and I need only mention the names
of Astbury, Backhouse, Besley, Bridger, Brook, Alex. Herschel,
and King.

" Other good men, such as Blakeley, Booth, Clark, Corder,
R. P. Greg, Wood, and a few more, have relinquished labours
in this field.

" Prof. Alexander S. Herschel has accomplished a vast
amount of valuable meteoric work during the last 45 years,
and this department of astronomy will ever stand indebted to
him as one of its most able and tireless pioneers."

A NeNv Chart of Mars.

Herr Leo Brenner has recently issued a new chart of .Mars
from observations made in Lussinpiccolo from 1894-1903.
The chief feature of the chart is the indication of the minor
markings, "canals" and "lakes," in different colours accord-
ing as they have been discovered by Schiaparelli, Lowell, or
by Brenner himself. The result is a network of lines so close
and intricate as to prove to demonstration that it cannot
possibly represent any real and permanent features of the
surface of the planet. The majority of these markings,
exceeding three hundred in number, if actually observed must
belong to one of two classes ; they must either be pure illu-
sions on the part of the observer or must be perfectly
ephemeral markings on the planet, possibly of the nature of
meteorological change. The leading markings, the great
"lands" and "seas," are shown under forms so stift' and
rectangular, and with so little of detail, as to indicate that
Herr Brenner enjoyed very few advantages as to atmosphere
or telescopic definition, or else that he was singularly unfor-
tunate in profiting by them.

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

243

A Scheme for the Comparison of
Climates.

Is it possible to express the pU is.mtness or unploasaiitness
of .1 climate on a scientific scale ? Captain W. F. Tyler,
F.R.Met.Soc, has attempted to form such a scale. Con-
cluding that the two dominant factors intlucncing our sensa-
tion of comfort are temperature and huuiidity, he has coined
the word " hyther " — apparently from the first syllables of
"hygrometer" and "thermometer" — to indicate this joint
effect. .-V perfectly pleas.ant day is registered o on this hyther
scale, and an intolerably oppressive one as 10. Captain
Tyler's own observations of " hyther " extend over several
years, but in the end of the summer of 1902, he was able to get
the cc-operation of eleven other observers for the systematic
observation of "hyther" throughout the month of August.
The results of the comp.arison showed that most persons
would require a considerable amount of practice before their
observations could be considered trustworthy, but some
approach was made towards the establishment of a definite
law connecting the temperature and humidity witli the
hyther sensation. .-Vt the same time there were indications
that some other factors, possibly barometric pressure or electric
conditions, had an appreciable influence upon the sensation.
The subject seems well worth working out on a more extended
scale.

* * *

The Paris Observatory.

The annual report of the I'aris Observatory for 1903, pre-
sented to the Council on March 22 of the prescut year, deals
with a number of researches of speci.al interest. The seventh
section of the Atlas of the Moon has appeared, containing
seven plates which seem the most successful yet issued, and
in some respects to show a considerable advance over the best
\-iews of the moon obtained by the eye at the telescope. With
respect to the .•^strographic Chart, eleven plates have been
passed as satisfactory, and thirty-five charts containing the
triple images of 47,300 stars h.ave been distributed. It is hoped
that the second volume of the Photographic Catalogue will
appear by the end of the current year. The determination of
the solar parallax from the photographic observations of Eros is
advancing towards completion. Of standard stars 1 66 1 meridian
observations have been made, and 10,858 photographic obser-
vations of comparison stars, of standard stars, and of stars
near the path of Eros, Three important researches based
upon new methods are included in the programme for the
future work of the observatory : the first relates to the deter-
mination of latitude and of its variations; the second is for
the precise determination of the constant of aberration, two
portions of the sky, distant go", being presented in the field of
the instrument at the same moment by means of a double
mirror; and the third relates to the employment of M. Lipp-
mann's photographic object-glass in meridian observations.

* * *

R^e= discovery of Encke's Comet.

Encke's comet was re-discovered at the Kiinigstuhl Obser-
vatory on September ti at i3h. i6-gm. local mean time. Its
right ascension at discovery was i' 46' 16", and its declination
N. 25' 24'. This is the thirty-sixth return of the comet since
its discovery in 1786; the twenty-ninth during which it lias
been observed.

BOTANICAL.

By S. \. Skan.

The Comptcs Rendiis, vol. cxxxvii., contains some valuable
observations on the germination of seeds of orchids by Mons.
N. Bernard, whose experiences warrant his making the inte-
resting and rather remarkable statement that germination, at
least in the case of some seeds of CattUya and LacUa with
which he experimented, is wholly dependent on the presence
in the embryo of a filamentous endophytic fungus. In a fort-
night after sowing the seeds some minute spherules, rendered
evident by their green colour, were produced. Some of the

epidermal cells of these bodies elongated into short papillaj,
but did not form any true hairs. It was observed that in
aseptic sowings, even after the lapse of five montlis from the
time when the green spherules made their appearance, no
further development of the seeds had taken place. Many
were destroyed by mould, sooner or later. If, however, the
.seeds in the state indicated were transferred to a tube in
which was .a culture of a certain hyphomycelous fungus,
further growth almost immediately resulted, and it was found
that the hypha' of the fungus had penclr.ited the median part
of the suspensor and the adjacent cells of the embryo. In
fifteen d.ays the seedlings had assumed their characteristic
top-shaped appearance, developing a terminal bud and long
absorbing hairs. In the cultures, besides the fungus which
Mons. Bernard regards as necessary to germination, a
coccobacillus was present, but it did not appear to have any
effect, either in hindering or promoting germination; if, how-
ever, other fungi or bacteria were substituted for the particu-
lar kind of fungus found to be essential, the seeds, instead of
germinating, were destroyed.

\ rose which h.as created a great deal of interest in horti-
cultural circles is the subject of one of the plates in the Sep-
tember number of the lUitanical Mai^azinc. The late Sir
H(;nry Collett met with this rose, to which he gave the name
of Rosa f;if;itiilcit, as a very striking object in the forests of the
Shan Hills in Northern lUirnia, and it was through him that
seeds were received .at the Royal Botanic Gardens, Kew, in
1888. No ditlii'ulty was experienced in getting the seeds to
germinate, and the seedlings soon developed into plants
remarkable for the enormous length of theu' shoots, one of
these in the Temperate House reaching a length of fifty feet.
N'isitors to the Succulent House may have observed the
robust specimen planted in the central bed there, which had
grown along the roof, and then out through a ventilator into
the open air. 15ut though growths were produced in almost
embarrassing freedom, no llowers have ever been borne by
the Kew plants. Indeed, it is believed that only in two
gardens in this country has the plant flowered at all. From
one of these — .'Mbury Park, Guildford — the material was
obtained from which the Dutanical Maf^azinc drawing was pre-
pared. The flowers are white, or white tinged with yellow,
and are from four to six inches in diameter. The same rose
was found first in Manipur, and it is now known to occur in
Western China.

ORNITHOLOGICAL.

By W. B. BvcR.MT.

Brush Turkeys breeding in Confinement.

Mk. BivRTLINg, in the August number of the A^'uiitlural
Magazine, concludes his notes on the breeding of the Brush
Turkeys ('ralci;alla UHluimi) in the Gardens of the /Zoological
Society.

His account, though short, is extremely interesting and of
considerable scientific value.

Some time since, these birds constructed a mound of the
usual type, and deposited therein a number of eggs. The
nestlings being overdue, it was at last decided to at lea.st par-
tially explore the mound, and this resulted in exposing three
eggs. These lay about one fool apart from each other, and some
18 inches from the surface. They were placed with the large
end upwards, and had certainly not been turned, as a deep
hole, of the shape of the egg, was left on its removal. More-
over, the egg did not touch the bottom of the hole, inasmuch
as the small end was quite white, whilst the rest of the shell
was stained by contact with the mould.

A further search revealed a chick, evidently dazzled by the
sudden glare of the light. The "(|uills" of this bird were
nearly 3 in. long, and as it could fly fairly well, he says,
'■ 1 have come to the conclusion that the yoimg remain at
least 36 hours, or longer, in the mound before making their
appearance, as three others, hatched in an incubator, were not
nearly so advanced when hatched."

The shell is very thin, so that the young do not chip round
the upper part of the egg in order to make their escape, but

244

KNOWLEDGE & SCIENTIFIC NEWS

[Oct., 1904.

appear to shatter the walls of their prison by giving a violent
wriggle. They do not immediately obtain freedom, however,
but still remain encased in the inner membrane of the shell,
which is rnptured some hours afterwards.

When first hatched the primaries and secondaries are
ensheathed in a " thin filmy covering " which gives the wings
the appearance of being still undeveloped, but directly the
chick dries this membrane peels off, leaving the bird ready for
flight.

At three weel;s the black feathers of the adult plumage
are distinctly visible through the " down," and at six weeks
the birds are almost indistinguishable from the parents.

* * *

Breeding of the Tataupa Tinamou.

(Crvptuyns tataupa.)

Mr. Seth-Smith is the first to have succeeded in breeding
this rare bird in confinement, and as nothing was hitherto
known of its habits at this time his short description thereof
in the AviciiHural Magazine for August is of considerable
interest.

The eggs are incubated by the male only. From the
moment he began to sit the female resigned all interest in the
matter: indeed, if she approached, her mate rushed at her open
mouthed so that she fled in terror ! Before leaving them the
eggs were most carefully covered up. After the escape of the
young from the egg shell the male broods them for some hours
before bringing them out into the open.

The female does the courting, calling to her mate and then
running to him, and displaying in the most curious attitudes.

When alarmed these birds adopt the peculiar device of
throwing themselves forward on the breast and throwing the
tail in the air so that the under-tail-coverts form a screen to
hide the body ; which in consequence becomes hard to dis-
tinguish from the surrounding herbage and undergrowth.
Even very young chicks, when they suspect danger, squat and
turn up their sprouting tails, but whether instinctively or in
imitation of the parents the author does not say.

* * *

The Weight of Eggs.

In our last issue, it will be remembered, we referred to a
paper on the loss of weight of eggs during inculjation. The
/o.)loi;ht for August contains some extremely interesting notes
on the range of variability in the weight of eggs of wild birds,
which is much greater than one would have imagined. The
eggs of the Charadriidje were used to furnish the matei'ial for
this investigation, and the strictest care was used to select
only unincubated eggs, thus eliminating the error due to loss
from this cause. The weight of the whole clutch, and not of
single eggs, is given. Altogether, about a dozen species have
been studied in this connection, and four or five clutches of
each species have been weighed. In Jigialits hiaticula, the
lightest clutch weighed 45'i48 grammes, the heaviest 50'450
grammes; in Charadrius pluvialis the differences were ijO'iOy
grammes and isi-agg grammes; in I'aiwtlus vulgaris, io6'62i
and iiy434 grammes; in Numciiiiis arquatiis, 320'ii4 and
348'ii6 grammes; in Totanus caliiiris, 82'i64 and g2'6S7
grammes. It would be interesting to compare the relative
differences in weight between the birds of the species
enumerated and their egg clutches, and to note the difference
between the activity of their young on hatching. So far, no one
seems to have noticed whether this differs to any appreciable
extent among the different species of Charadriid;e.

* * *

The Systema.tic Study of Bird Life.

The foundation of an Ornithological Observatory is an
event which may be said to mark an epoch in the study of
ornithology. Such an establishment has just been started in
the United States. It is to be known as the " Worthington
Society for the Investigation of 15ir<l Life," and has been
erected and endowed by its founder, Mr. C. C. Worthington.
on his estate at Shanee, Monroe County, Pennsylvania.

The programme laid down is exhaustive in its comprehen-
siveness, but we may draw special attention to one or two of
its particularly interesting items. In the first place particular
attention is to be paid to life histories. Observations on an
elaborate scale are to be made so as to embody as many

details as possible concerning the growth, food, and habits of
individuals in a wild state. The study of the vexed question
of variations, their nature, and cause ; and colour changes
with respect to age, sex, moult, season, and climate should
yield much. The problems of heredity, experiments in hybri-
dising, and psychological observations are to be carried on in
specially constructed aviaries. Another important feature is
the proposal to test the possibility of breeding insectivorous
and otlier useful birds with a view to re-stocking depleted
areas, as has been done in the case of fish by the Fish Com-
mission.

The carrying out of this great enterprise has been entrusted
to Mr. W. E. D. Scott, tlie Curator of the Ornithological
Department of the Princeton University. This augurs well
for its success ; indeed we know of no other man who is so
peculiarly fitted for such a task. He will be aided by a staff
of assistants.

We cannot refrain from expressing a desire to see a similar
institution at work in this country. Perhaps the Board of
Agriculture may be induced to consider the matter.
# * *

Snap-shots from Bird Life.

We have peculiar pleasure in bringing to the notice of our
readers a very wonderful collection of stereoscopic pictures
which have just been issued under the above title. Every
picture has been taken from life — and about their genuineness
there can be no question — by M. P. L. Steenhuizen, of Amster-
dam. Though these photographs were taken in Holland, all
the birds in the series occur in Great Britain. A more mar-
vellous and a more beautiful collection it would be impossible
to imagine, and at the present time they are probably unique.
Since there are no less than 48 slides in all, we cannot give a
list of the subjects, and we find it peculiarly difficult to select
any for special mention, for all are alike exquisite. But to
give an idea of the variety of the selection, we may mention as
especially striking the nest and eggs of the pheasant, the nest
and young of the marsh harrier, the nest and young of the
spoonbill, the nightjar and its eggs, and the nest and eggs of
the great reed warbler.

I shall be glad to give p.articulars to those who may desire
to procure copies of this really wonderful series.

PHYSICAL.

Electrical Wave Measurement.

In the June number of " Knowlkdge," a description was
given of the means which Professor J. A. Fleming, F.R.S.,
employs to investigate the propagation of electric waves along
spiral wires; and a diagram was appended to show the vvay in
which the apparatus can be employed for measuring the length
of waves used in wireless telegraphy. We reproduce the dia-
gram again below : —

A, B.— Long: coil of 5,000 turns ot

No. 36 wire.
W. -Earth Wire.
Li. L^. — Leyden .lars, each "0014

mfd. capacity.
X. — Variable Inductance Coil, 0-230

microhenrys.
I. Induction Coil— 10 inch spark-
S. — 5park halls.

In practice the method consists of establishing stationary
electric waves on the spiral wire, and of deducing, by mathe-
matical reasoning, the wave length of the induced wave. The
experiments described previously in " Knowledge " were
made with a long helix of insulated copper wire, wound in one
layer on a wooden rod. Wood, however, has since been
found to be unsuitable for obvious causes ; and an ebonite rod

Oct., TO04.

KXCnVI.KPGE & SCIFNTIFIC NEWS.

245

has been substituted. The hehx of wire consisted of 5000
turns, the length being joo centimetres. If such a helix is
placed in connection with an oscillating circuit consisting of a
condenser or Leyden jar, a spark gap, and a variable induct-
ance, stationary waves can be set up on the helix by adjusting
the inductance in the oscillating circuit. In order to detect
the nodes and antinodes of these stationary oscillations. Pro-
fessor Fleming makes use of a vacuum tube, similar to that used
in spectrum analysis, and preferably one filled with the rare
gas. Neon. Rarefied Xeon seems to be extremely sensitive to
the presence of variable electric force through it ; hence, if
such a tube is held perpendicular to the helix, .and moved
parallel to itself along it, it glows brightly at the antinodes, but
not at the nodes. In this manner the internodal distances
can be measured with considerable accuracy, and the wave-
length of the stationary oscillation measured.

Now the velocity with which the wave is propagated along
the spiral can be shown to be inversely proportional to the
square root of the product of the capacity and inductance of
the hehx per unit of length. Professor Fleming has perfected
of late years methods for measuring very small capacities and
inductances, and in the case of the above-named helix the in-
ductance is equal to 100,000 centimetres per centimetre,
whilst a capacity of the helix is ,"„ of a micro- microfarad.
(I micro-microfarad = lo^' microfarad.)

From these data the velocity of propagation of electric
waves along the helix can bs shown to be 235.030.000 centi-

along it can be calculated as above shown, and hence the fre-
quency of the oscillating circuit becomes known. If this
freciuency is divided into the velocity of light, reckoned in
feet, it gives the wave-length in feet of the wave radiated from
the associated aerial, provided that the aerial radiating wire
has been tuned to be in resonance with this oscillating
circuit.

This instrument also pnivides tin- means of measuring sm.all
inductances, and also the frequencies in oscillating circuits,
which are much higher th.ui those wliich can be determined
by photographing the spark.

Thought R^a-ys.

M. di BvAzzh, a student at Liege, who sent an account of
Becquerel's work on radio-activity to the Scculo A'.V. for
January, 1903, now describes the I-r,ays as discovered by
himself when repeating the N-ray experiments of M. Blondlot
and of Professor Charpentier. Charpcntier succeeded in
demonstrating that the human body emits Nrays. He found
that the phosphorescence of certain substances is increased
when they are brought close to a nerve or contracting muscle,
i.t\ muscular work is accompanied by a marked emission of
N-rays. By means of a simple apparatus, a lead tube 7 cm.
long (lead was chosen because it was opaque to the human

Professor Fleming's Kummeter.

metres per second. This figure is confirmed in the following
manner: The capacity and the inductance in the oscillating
circuit are both measured when the first harmonic oscillation
is formed on the helix, and under those conditions the h.alf
wave-length was found to be 140 centimetres, whilst the
frequency in the oscillating circuit, as calculated from the
capacity and inductance, was found to be o'iS47 x lo".

Having, therefore, the wave-length and frequency, we find
their product gives a velocity of 235,000,000 centimetres per
second, which agrees with the figure determined from the con-
stants of the helix.

The best form of inductance to be employed in connection
with the oscillating circuit is a square of one turn of wire; the
employment of spiral coils leads to errors due to passage of
a dielectric current from coil to coil. The improved instru-
ment which Professor P'leming has now constructed, and
which is based on the foregoing considerations, he calls a
"Kummeter." It is constructed as follows: A long ebonite
rod is wound over closely with silk-covered wire in one layer,
and this is supported on insulating stands. On this long helix
slides a metal saddle having some layers of tinfoil interposed
to make good contact between the saddle and the helix. This
saddle is connected by a flexible wire with the earth. One
end of the helix is furnished with an insulated metal plate,
which is placed in apposition to another metal plate connected
to the oscillating circuit of the transmitter. The process of
measuring the wave consists in sliding the saddle along until
a Neon vacuum tube indicates the presence of one node half-
way between the saddle and the plate. When this is the case
the distance from saddle to plate is one wave-length of the
stationary wave on the helix.

From the constants of the helix the velocity of the wave

rays, and accordingly lessens diffusion), closed at the end by
a sheet of paper, or bit of silk covered with phosphorescent
calcium sulphate, it is possible to observe the different nervous
centres of the cerebral cortex. Thus by placing it in appo-
sition with Broca's centre (the centre of articulate speech)
while the patient is talking, variations are produced in the
luminosity of the phosphorescent calcium sulphate. In
another experiment, Charpentier saw the phosphorescent
substance shine all down the line of its application to the
spinal cord. Charpentier concluded that the emission of rays
goes pari passu with activity of function, whence we should be
in possession of a new method of stuilytng nervous and mus-
cular activity. Di Brazzil claims to liave demonstrated what
Charpentier only surmised, i.e. that " the brain is the seat of
active radiation." The I (Italy) rays differ from the N in
that they can pass through moist substances, and are not bent
nor refracted. Di Brazzi observes them directly and indirectly.
In direct observation he applies a phosphorescing screen
treated wiih platinocyanide of Ba.,or other phosphorescent
substances, to the patient's head. The screen is faintly illumi-
nated by a radiographic tube (tubo-focus) enclosed in a
wooden box. When the subject concentrates his will, curious
oscillations appear in the luminosity of the screen in relation
with the patient's psychical activity. When his attention is
not concentrated, the light does not flicker. The rays are not
emitted equally from all parts of the head. They are nil at
the forehead and upper part of Broci's centre, increase at
the temples and eyes, and reach their maximum behind the
ears. In photography, precautions must be taken to secure
uniform length of exposure (di Brazza introduces an automatic
interrupter), sensitivity of plate, conditions of development,
6cc. Di Brazza always uses ortho chromatic plates.

246

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

Wireless Telephony.

In order more closely to investigate the phenomena attend-
ing the disruptive discharge of a Kuhmkorff coil, Mr. F.
Lifchitz, as recorded in a paper recently presented to the
Russian Physico-Chemical Society, places a concave mirror on
the axis of the Ducretet commutator working the coil. On
account of the synchronism, a fixed image of the spark is
obtained on the screen instead of a Federsen band, as
obtained in the case of the rotation of the mirror being much
more rapid. The image observed is a single one in the case
of the spark length being maximum, 2, 3, etc. images — up
to some dozens — being realised as the distance of the electrodes
from the spark becomes less. In order to be able to record
these observations, the author fitted a photographic plate
instead of the mirror verticallv to the axle of the commutator,
when the images of the sparks followed up each other at in-
creasing intervals, beginning with -rs'-sHn second. This goes to
confirm Hertz's opinion, according to which the discharge of
the coil would carry an amount of electricity much greater
than that of an electrostatic machine in virtue of the more
rapid increase in potential. The number of impulses obtained
for the same length of spark varies directly as the intensity
of the current traversing the primary circuit. Now let the
commutator of the coil be replaced by a microphone acted
upon by the voice of the experimenter. Each letter pro-
nounced will result in a series of disruptive discharges, the
series of impulses being the longer as the pulsations are
stronger. The vibration thus set up may be received by the
aid of a decoherer. A whole series of vibrations following up
e.ach other at intervals of some 10,000th of a second will result
in a single variation in the resistance of the decoherer, being
the greater as the series is longer, and the time necessary for
producing decoherence being of some thousandths of a
second.

ZOOLOGICAL.

By R. Lydekker.

The Blood of Men a.nd Apes.

At the Anthropological Congress recently held at Grcifswald,
Professor Uhlenhuth described at considerable length the re-
sults of experiments he had undertaken with the view of ascer-
taining whether any closer affinity exists between the blood of
the man-like apes and that of man than between the latter and
the blood of the lower monkeys and mammals in general.
1 he result is to show that, although it is perfectly easy to dis-
tinguish between human blood and that of the lower mammals,
it is much more difiicult to demonstrate under the microscope a
satisfactory distinction between the former and that of apes
and monkeys. But this is by no means all ; for, whereas the
resemblance is greatest between the blood of man and that of
man-like apes, it becomes less strongly marked when that of
the lower Old World monkeys is compared, still less so in the
case of the American monkeys, and least of all when the blood
of the lemurs is under comparison. This is exactly what might
have been expected to occur, seeing that the lemurs dep.art
most widely of all the Primates from the human type.
» » »

The Gorillas a.t the " Zoo."

The recent arrival at tlie Zoological Society's menagerie of
two apparently healthy young gorillas was an event of great
importance and interest. Unfortunately, the elder of the two
{aiat 5^ did not long survive, succumbing to a disease which
was apparently already in its system at the time of its pur-
chase. The other and younger animal, which was supposed to
be three years old, has also died. Only two gorillas have pre-
viously been exhibited in the Regent's Park. The first of
these was a young male, purchased in October, 18S7, from Mr.
Cross, the well-known Liverpool dealer in animals. At the
time of arrival it was supposed to be about three years old,
and stood zh feet in height. The second, which was a male,
and supposed to be rather older, was acquired in March, iSq6,
having been brought to Liverpool from I'rench Congoland by
one of the African Steamship Company's vessels. It is de-

scribed as having been thoroughly healthy at the date of its
arrival, and of an amiable and tractable disposition. Neither
of these animals survived long.

So long ago as the year i.St5, when the species was known
to zoologists only by its skeleton, a living gorilla actually
existed in this country. This animal, a young female, came
from French Congoland, and was kept for some months in
Wombwell's travelling menagerie, where it was treated as a
pet. On its death, the body was sent to the late Mr. Charles
Waterton, of Walton Hall, by whom the skin was mounted in
a grotesque manner, and the skeleton given to the Leeds
Museum. Apparently, however, it was not till several years
later that the skin was recognised by the late Mr. A. D.
Bartlett as that of a gorilla ; the animal having probably been
regarded by its owner as a chimpanzee.

Of the two recent arrivals at the " Zoo.," one appears to
belong to the true gorilla (Aiithrflpopitluriis i^orilln), while the
other represents the red-headed gorilla, which has been de-
scribed as Gorilla castuiwicips. It is now definitely known that
there are several local forms of gorilla, of which one inhabits
East Central .Africa ; but naturalists are by no means in
accord as to whether they should be regarded as species or
sub-species. If the latter view be adopted, the gorilla should
be included in the same genus as the chimpanzee (Anthro-
pi'pitlu-ciis}, but, if the former course be followed, it would pro-
bably be better to regard the various species as representing
a genus (Gorilla) by themselves.

Whether it will ever be possible to keep a specimen in cap-
tivity in this country till full-grown remains to be seen. Since
the above-mentioned 3-year old example was only 2 J ft. in
stature, gorillas must probably take something like 15 or 16
years to reach maturity.

* * »

Fossil Mammals in the Ganges Valley.

An extremely interesting discovery of the remains of extinct
mammals has recently been made during excavations under-
taken for the foundations of the Ganges bridge at Allahabad,
India. The remains include those of one or two species of
hippopotamus, of a wild ox, and of an elephant, all belonging
to extinct species. .Apparently all these species are identical
with those long known from the valley of the Narbada, con-
siderably further south in India ; but it is possible that the
Ganges bones, like others discovered in the early part of last
century in the valley of the Jumna, may belong to a somewhat
later portion of the Pleistocene epoch. In all probability the
creatures they represent were cotemporaries of the early
human inhabitants of India; and the special interest of the
discovery lies in the possibility that it may give rise to inves-
tigations for the purpose of ascertaining whether human
remains may not occur in the same deposit. In connection
with the former existence of hippopotamuses in India, it may
be remarked that we have yet to learn why these animals died
out while elephants survived.

* * «

Mammoth Skull in Kent.

We have also to record a very interesting palseontological
discovery at Erith, in Kent. A short time ago it appears
that while some labourers were working in a sand pit at
that place, they came suddenly upon an entire skull of a
mammoth, at a depth of about 2^ feet from the surface, with
tusks close on six feet in length. L'nfortunately they forth-
with proceeded to exhume the prize, which of course at once
fell to pieces. Had it been properly treated with size and
plaster, it might have been extricated whole, when it would have
formed a most valuable specimen, as only one entire British
mammoth skull is known.

* * *

The Later History^ of the Horse.

This subject was discussed at the late meeting of the British
Association by Professor Ridgeway, who urged that while the
ordinary "cold-blooded " horses of Europe and Western Asia
trace their descent to a dun-coloured stock more or less nearly
resembling the Mongolian wild ponies, Arabs and thorough-
breds are descended from a l>reed whose colour was bay. fre-
quently with a white star on the forehead .and a white ring on
the fetlock. This ancestral bay stock, it is urged, originally
came from North Africa, whence it migrated into Western

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

247

.Asia. There is imich in this theory to attract the best atten-
tion of the zoologist, althoiisjh the absence of any evidence
that wild horses ever existed iu North .Vfrica mihtates against
an African origin for the bay stock. Moreover, when the
author suggests that the white " stocking " on the fetlock of
the Arab recalls the white rings on the foot of the zebras he is
treading on dangerous ground, although he appears to have
abandoned his wild theory that the .Arab and the thoroughbred
are descended from Grevy's zebra.

CORRESPONDENCE.

The Later History of tKe Horse.

'l\i ihil Eoirons oi- '• Know li-.ix.k."
Sirs, — Mr. Lydekker, in his interesting paper c Ksou-
LEDGE," .•\ugust, 1904, p. 171), makes a very usual error in
dealing with the relative degrees of finish exhibited in I'aheo-
lithic and Neolithic iinplements. Without previous know-
ledg3 of the subject of prehistoric inipleincnts, a reader would
gather that all I'aheolithic inipleinents are rude, and that all
Neoliths are ground or polished. This impression would to a
certain degree receive confirmation l)y a visit to ISioomsbury.
Nothing in truth could be more misleading. If I'alaolithic
implements are regarded as a cla?s, they show, especially with
regard to later types, a remarkable proficiency in the working
of flint. The only type which as a class can be termed rude
are the oft-abused 1-oliths : the l^abeoliths certainly do not
merit such a term, .\gain. it was the exception during Neo-
lithic times to grind or polish implements. It is not a little
significant to point out that, viewed as a class. Neolithic
implements are actually ruder than PaUeoliths — the propor-
tion of polished or ground impUnnents to those showing only
rough workmanship is infinitesimal. I am aware that the
museums do not illustrate this condition of things, but it is an
old grie\ance of the man in the field that on this point the
museums are misleading.

Might I suggest that the blocks of Tigs. 2 and 3 in Mr.
Lydekker's paper appear to be wrongly placed ?

^'ours faithfully,

J. KussiiLi, Lakkhv.
Bromley, Kent.

A Ba.ll-Bearing Rifled
Gui\.

In spite of the improvements of modern firearms, the device
by which rotation is imparted to the projectile as it leaves the
gun-bore has remained stereotyped. \'et a brief considera-
tion of the method of " rifling ' which imparts the rotatory
motion will show that it must interfere with one of the funda-
mental aims of the gun designer, which is to get his projectile
out of the gun with the greatest velocity possible. The pro-
jectile, in order that it may be susceptibleof receiving rotatory
motion, is provided with a band of metal into which the edges
of the rifled groove have to force their way. Consequently a
large portion of the energy developed by the charge is dissi-
pated in heat in the gun barrel. .'\n American inventor, Mr.
Orlan C. Cullen, has devised a method, quite sitiiple, and to
all appearance practicable, of avoiding this waste of energy.

He uses a cylindrical projectile of perfectly smooth, bard
steel, travelling upon the smooth and almost frictionless
path aftbrded by hard steel ball bearings. In the barrel a
number of grooves, usually eight, are cut of completely circular
section, except that a small arc is cut off so that each com-
municates with the bore by a narrow slot. Into these grooves
are fitted steel balls, which project through the slots to the
extent of about one-twentieth of their diameter, with the result
that the projectile travels upon a rolling bed which offers the
least possible resistance to both its forward and its rot.itory
motions. At first sight it might be supposed that the arrange-
ment would not be gas-tight. That, however, is not the case ;

the projectile is made to fit closely to the balls, and its elasticity,
combined with that of the walls of the grooves and of the b.ills,
insures that the gas dors not escape p.ist the bullet, which,
moreover, may be imagined as moving so easily and so r,i|)idly
that the gas has scarcely time to gel ahead of it.

The races, or grooves, in which the balls revolve .it the
breech end extend back to the powder cliumber, the projectile
lying so that its head just engages with the first ball in each
groove. .Vt the muzzle end the; grooves are closed with what
the inventor terms recoil-cushions, the twist of the grooves
ceasing for a short distance from the muzzle in order to admit
of their insertion. These cushions .are constructed either with
glvcerine or with steel springs, but, whichever device is used,
matters are so arranged that tlie compression transmitted
along each row of balls begins as soon as the projectile rulers
the bore and is complele as it leaves the muzzle. In this way
the inventor claims that recoil is done away with; the bullet
has a course so open and free from resistance that the initial
recoil is very small, and what there is is taken up by the recoil
cushions, the tendency of the bullet being rather to drag the
gim after it than to kic-k it away behind it.

In regard to performance, the inventor stales that lie gets
40 per cent, greater average velocity, penetration, and range
than can be obtained with the same weight of projectile and

.Sectiun^ showing Rifling and Ball iiearings.

charge in guns made on the old system. His • 50 ; gun has a
muzzle velocity of -j^oo foot-seconds, and .1 point-blank range
of 650 yards, compared with the 480 of the I'ritish service rifle
of the same bore, using exactly the same charge, and, while the
latter can drive its bulli;t through 72 one-inch boards, the
Cullen gun can penetrate 116. The Cullen gun of the same
calibre is 6 ins. or 7 ins. shorter, though its weight is about the
same, because the barrel is thicker, and its rifling makes four
complete turns, against three in the Lce-lCnfield. The balls
used in the grooves of a rifle of this calibre are one-tentli of
an inch in diameter ; in a 4-in gun they are lliree-quarters of
an inch.

.'\nother advantage claimed for the gun, due to the compara-
tive absence of friction between the bullet and the ball bear-
ings, is that the barrel does not heat ; so markedly is this the
case that with Maxim guns it is said to be possible to dispense
with the cooling jackets which have given so much trouble in
Tibet. The absence of recoil (which, however, can be obtained
by contracting the bore, if it is wan ted for any reason, as for work-
ing the Maxim-firing mcchanisiii) again has important conse-
quences, since it does away with the necessity for complicated
carriages and mountings intended to take up the recoil. Mr.
Cullen has a sixpounder which he fires regularly with no more
elaborate mounting than a block of wood, and he claims that
his guns, except when they are so heavy as to require
mechanical appliances for training, could quite well be used
with the anti(|ue gun-carriages which now serve no more use-
ful purpose than to afford a pictures(|ue decoration to some of
our public places. Ships, loo, should no longer need to have
their structures specially strengthened iu order to withstand
the strains set up by the firing of their ordnance.

248

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

REVIEWS OF BOOKS.

Radio-Activity. — Three books have recently been published
on radio-activity and the properties of radium ; and of these
three, that written with the title of •' Kadio-Activity." by Pro-
fessor Rutherford. D.Sc. F.K.S. (Canibridi;e: University
Press), niav be taken as the standard work on the subject. To
Professor Rutherford more than to any other one person is
to be ascribed the proof of the disintegration theory of radium ;
and the demonstration that the rays and the emanations which
are characteristic of radio-active substances are merely
svmptoms of the decay of the elements. We use the word
••"proof," though the proof is far from complete, and the in-
ferences which Professor Rutherford draws from the proper-
ties of the a, ,rf, and 7 rays of radium, or from the conversion
of the gaseous emanation of radium into helium, are still dis-
puted by many chemists. If the inferences which Professor
Rutherford draws are the right ones, then we should e.xpect
nearly all substances to be more or less radio-active. Pro-
fessor J.J. Thomson, at the recent meeting of the British
Association, declared that, in his opinion, they were so ; and
though Professors Elster and (jcitel, whose work in radio-
activity entitles them to the most respectful hearing, did not
accept all Professor Thomson's conclusions, it is hard to see
how they are to be refuted. As Sir Oliver Lodge has re-
marked, if we accept the electric theory of matter, then one
might almost say that there is no need to piove the radio-
activitv of ordinary matter, for the burden of proof should
rather lie on the shoulders of opponents of this view, who
must show that it is not. If we are then to take the most
generally-accepted view of the reasons for the phenomena of
radium, a view which is now accepted by one of the greatest
of the earlier sceptics. Lord Kelvin, we must allow the views
put forward in Professor Rutherford's" Radio-Activity" to be
the only ones that can endure the test of examination. They
are, in a nutshell, that all the phenomena of radium are caused
by the splitting up of the atoms of which radium is composed,
aid their dispersal as electrons, or as new combinations of
electrons. The alternative view that there was something in
the constitution of radium's molecules or atoms which enabled
it to draw supplies of euergv- from the surrounding ether, or
from some other unknown sources of energy, has been declared
by Sir William Ramsay to be supererogatory. ."^mong the
special features of the book arc the historical treatment of the
discovery of the various phenomena of radium : The heat
emission (MM. Curie and Labordel ; the 3 rays: Sir William
and Lady Muggins's spectroscopic researches; a discussion
of the possible origin of polonium ; and a full account of the
results obtained by Sir William Ramsay and Mr. Soddy in
the production of radium emanation from helium.

Mr. Soddy's book, "Radio-Activity" (the "Electrician"
Publishing Company), bears to Professor Rutherford's larger
work much the same relation that Puckle's " Conic Sections,"
which was sometimes called Puckle's •' Salmon," bore to Dr.
Salmon's classic volume. This, however, is hardly fair to Mr.
Frederick Soddy, who is an investigator of great brilliance
and a writer of uncommon clearness, modesty, and per-
spicuity. He describes in the most admirable way the experi-
ments in which he has been associated both with Rutherford
and Ramsay, and his book, while not as exhaustive as that of
his former colleague, puts in a concise form the speculations
and conclusions to which the experiments gave rise. There
is at the end of his book a chapter called " Anticipations,"
which in its title, if not in its subject matter, is perhaps
a little rash, but, as Professor Horace Lamb has said, •'even
in mathematics something must be risked." and Mr. Soddy's
speculations on the vistas of theory opened to our eyes by
radium are interesting to the point of enthralment.

The third book which we have to include under this notice
is " Radium," by Leonard A. Levy and Herbert J. Willis
(Percival Miirshall and Co.); l>ut in so including it we are
bound to confess that w-e do it something more than justice.
It is not a text-book, nor yet is it quite a popular work in the
style of " Kadium-and-all-about-it," but is something between
the two. To those who wish to get a gener.d vit-w of radium's
properties, sufficiently accurate, and not at all heavy in com-
position, we may recommend it as a preparation for more
substantial works.

The History of Painting in Italy. — The full title of Crowe and
Cavalcasselle's incomparable work, the first two volumes of
which have just been re-published by Mr. John Murray, and
the remaining four of which, edited by Langton Douglas and
the late Arthur Strong, are to follow in due course, runs " A
History of Painting in Italy. Umbria, Florence, and Siena,
from the Second to the Sixteenth Century." But the substi-
tution of one substantive for another is justified by the fact
that the history which Sir Joseph Crowe was assisted by
Signor Cavalcasselle to compile, remains now. as it was then,
distinctively and unalterably the history of the evolution of
the painter's art in Italy. As Mr. Langton Douglas incontro-
vcrtibly remarks, notwithstanding all that has been done in
the last forty years, by archivists on the one hand, and by
connoisseurs on the other, with the object of elucidating the
history of the central Italian Schools, this book continues to be
the standard authority upon the subject. It is in one sense
more than that. It is one of the few books of scientifically
accumulated facts, of which it might be said that an English
work is the admitted European authority. In the collection
of " co-efficients " on which to base theories the Germans are
apt to beat us. This work has all the laboriousness of German
effort without any of the repellent appearance of it ; it is, in
short, a work of art as well as a monument of human learning.
It is encumbered with few of those theories which are ac-
counted precious in one generation only to be forgotten in the
next ; but to the student who considers art from the point of
view of its evolution, it presents all the raw materials for
theory. If ever there should arise some Darwin among the
historians of painting — which perhaps the painters might pray
heaven to forbid — he would find no other work than this by
which he might trace the gradual evolution of a style or a
method ; the tendency to variability could be illustrated from
these pages ; the mutations arising from the accident of
genius could be dated and their influence assigned. This is.
however, to let one's imagination run away with one to an
extent that would have been severely discountenanced by the
authors, whose practice it was to admit no fact that had not
borne the test of the severest scientific questioning ; and we
iiiav fitly conclude this notice of a famous book by the state-
ment of the necessary facts concerning the new edition. The
original edition, now quite out of print, and very rarely to be
bought, and only at a great price, was enriched with few illustra-
tions. Its unique exactness and comprehensiveness was its
sufficing recommendation. Thenew volumes are illustrated with
all the resources of modern photography. Sir Joseph Crowe's
additions to the first four volumes, amounting almost to re-
writing, have been incorporated ; and to the original text
most valuable notes by Mr. Langton Douglas and Mr. Strong
have been added in smaller type. The first two volumes are
"Early Christian Art" and " Giotto and the Giottesques."
The Sienese School, the Florentines of the Quattrocento
and Cinquecento and the later Sienese and Umbrians will
follow.

The Classification of Flowering Plants. — Dr. Albert Rendle's
task in the latest volume of the Cambridge Biological Series,
"The Classification of Flowering Plants " (Cambridge Univer-
sity Press), is to present to the student the considered results
in classification which are afi'orded by the latest research in
systematic botany. This, the first volume, deals with the
Gymnosperms. pines, cedars, spruces, &c., and with the
Monocotyledons, the lilies, grasses, and palms. The Dicotyle-
dons will appear in the second volume. Historically, the
general introduction is of the greatest interest, for here is to
be found a clear comparative summary of the successive
schemesin which Luin;Eus,Jussieu,andthe DeCandolles sought
to express the resemblances and relationships of the flowering
plants. Dr. Rendle has done something more than present
summaries of these classifications; his method of presenting
them is an essay in comparative criticism. In the rest of the
book Dr. Rendle adheres to the most generally-accepted
models of classification. That of the Gymnosperms includes
the latest palarontological discoveries of Drs. D. H. Scott and
Oliver. In discussing the Monocotyledons, the arrangement
of Dr. Engler is the one to which he adheres. There may be
some difference of opinion in respect of the nomenclature
adopted in the classification of the Monocotyledons; but of
the value of the work as a standard text book there can be but
one opinion. It is extremely well illustrated.

Oct. ici: "

KNOWLEDGE & SCIENTIFIC NEWS.

249

British Mosses. — The doclared object of the first edition of
" The Student's H.indbook of British Mosses." by M. N. Dixon
and H. G. Jameson (Snmfield, I'astbounie : Wholdon. London),
was to provide a practical handl)Ool< to the mosses of these
islands in snch a form as to be accessible to students: and we
are pleased indeed to see that after eif;ht years this modestly-
stated ambition has been rewarded by the call for a second
edition. It is a reward far from immodest for a book which is
in the highest degree useful, not to say indispensable, to the
student : and which is compiled with a wealth of care such as
perhaps would be taken by no one but the painstaking race of
botanists for whom the consciousness that genius is the
cap.acity for taking small pains must be a frequent, .md. we
hope, a not altogether barren consolation. Since the pulilici-
tion of the first edition sonic thirty species or subspecies have
been added, tSgcther with ,a corresponding number of varieties
of greater or less value. Recent research has added more
precise knowledge of older varieties and has sometimes made
changes in nomenclature necessary. It has not been possible
to interpolate these additions to knowledge bodily in the
volume without some alteration in its arrangement : but the
changes that have been made in a classification, with which
the authors had every reason to be satisfied, have been made
with extreme care. The authors believe that such as are m.uU-
will be found to be improvements, a belief which criticism
may endorse.

Electro Chemistrj'. — To the series of text books on Physical
Chemistry ^Longmans. Green) to which Sir William Ramsay
wrote the general introduction, Dr. Lehfeldt has contributed
the volume on '• Electro Chemistry." This volume deals with
the theoretical side of the subject only ; the application of
the theory to the practical consideration of primary and
secondary cells, to electrolysis, and to the solution of chemical
problems is to follow. The relation between quantity of
electricity and quantity of chemical action is elucidated in a
chapter ranging from the consideration of Faraday's laws of
electrolytic deposition to the Arrhenius theory of dissociation
and its corollaries in respect of the conductivity of mixtures.
The relation between electric intensity and the intensity of
chemical action follows as a sequence to the first, and con-
siders the theories of concentration, polarisation, &c., under
the comprehensive heading of the theory of chemi-electro-
motive force. \ chapter which the preface obligingly states
can be missed by those who are not interested in pure
chemistry, but which will probably not be missed by anvone
who desires to keep in touch with the modern theories of
chemical solution, is interpolated by Mr. C. S. Moore, on the
relation of Chemical Constitution to Conductivity. The con-
centration of information in the text book is not its least
noticeable feature.

Kinetic Theory. — In "Applications of the Kinetic Theory"
(Macmillan), Professor W. P. Hoynton cndea\ours to present
the probable or possible relations to one another of the facts
of electrolysis, of osmotic pressure, and the general pheno-
mena of dissociation and solution, as seen by the light of the
kinetic theory. In successive chapters, the kinetic aspect of
ideal gases, of gases with molecules that have dimensions, of
the conduction of electricity and heat; of vaporisation ; of the
behaviour of molecules within a liquid: of solutions; of disso-
ciation and condensation, are dealt with. The volume is one
of great suggcstiveness to advanced students of physical
chemistry, and though the author disclaims any originality of
treatment, he displaysjudicial and selective powers of analysis
and arrangement of the highest order.

Visceral Inflainmations. — It has been said that there is a
fashion in diseases; and in this casual observation there is the
grain of truth that increased knowledge implies more precise
classification of diseases ascribed loosely to causes and symp-
toms which may be merely incidental. Thus, as we are re-
minded by the papers and addresses which Dr. David B. Lees
has collected in "The Treatment of Some Acute Visceral
Inflammations" (John Murray), the knowledge which in the
last twenty years has been gained of pneumonia, appendicitis,
. rheumatism, and the acute inflammations of the heart and
kidneys, has resulted in an apparent increase of the number
of cases classified under these heads. As an instance of what
we mean, we may (juote the cases of appendicitis, which for
generations past have been ascribed to varying causes, many

of them totally unfounded, but which are now grouped under
the primary cause of an acute local iufl.-unmation. Similarly,
the increase of knowledge in bacteriology has trausfornied
the view taken of diseases such as pniMuuouia, and is throw-
ing new light on many rheumatic allectious. But the advanc(^
of treatment of these diseases has not kept pace with the
advance of knowledge of their causes; and the treatises of
those who, like Dr. Lees, have euqiloyed sixteen years of hos-
pital work in the practical consideration of them, have the
highest value, and are of the highest interest inside and out-
side the medical profession alike. It is, of course, as a text-
book of medical treatment that such a volumi- is compiled;
but we h;ive no hesitation in according it notice iu columns
which are chiefly intended for the review of general scientific
literature. Its chief contents are lectures on carditis,
pneumonia, empyema, pleurisy, appendicitis, and nephritis,
with other papers on he;irt affections, their connection with
rheum.itism, especially in children ; and some of the heart
symptoms which follow influenza.

Common Animals. — Among the many good points of " The
Natural History of some Common Animals," by Oswald H.
Latter, M.A. (Cambridge L'niversity Press), is the extreiui'ly
natural and logical way in which it teaches elementary zoology.
Mr. Latter would divorce from elementary teaching of this
subject the notion that structure must occupy the first, and
almost the only, place in any method of study; and would
impress on the minds of tlie instructed the necessity for
learning function as well. In this way, .as we believe, lies the
best chance and opportunity of impressing on the mind of tlie
young student a liking for the subject; and in impressing on
his memory the relatively important details. Mr. Latter has
thus chosen a few animal types as the best to suit his purpose,
and has taught something about everything conceruiug them.
The types selected are the Earthworm, Leech, Crayfish, Cock-
roach, Dragonfly, Wasp, Fresh-water Mussel, Snail, Slug,
Frog, To.'id and Newt, and some of the common internal para-
sites of domestic animals, and of these he has given a full
biological and bionouiical n.arrative. Of its kind this book is
one of the best that has yet been written ; its manner and
matter are alike excellent.

Practical Geometry. — The " Practical Geometry for Begin-
ners " (Macmillan and Co.), which has been compiled by
W. L. Neve Foster and F. W. Dobbs, is based on the sound
logic that the best way of preparing the youthful mind for
theory is to suggest to it concrete values of lines, angles,
perpendiculars, radii, and all the other furniture of geometry.
Thus the book teaches geometry with the box of matliematlcal
instruments, and a triangle no longer rem;uns a symbol A BC
or D E !■", but is something tangible, measureable, comparable.
This is but a hint of the method which eventually [)roceeds to
the practical verification of theorems and laws, and which
may be couunendcd as practically useful and educationally
interesting. ^

Technical Thermometry. — The Cambridge Scientific Instru-
ment t'ompauy sends us a copy of their list on "Technical
Thermometry," together with an intimation that the lists can
be obtained from them, on application, by readers of " Knovv-
I.ICDGK." The list is a summary of the latest methods and
appliances in electric thermometry ; and, apart from its use to
students, it is of instructional value in defining the practical
applications of electrical thermometers in annealing furnaces,
in boilers and superheaters, and in explosive sheds. The
thermometer, and, above all, the exactly and inst.intancously
recording thermometer, has become, in recent years, of the
utmost importance to chemical works, to the brewing industry,
and to engineers and manufacturers in increasing numbers.
The catalogue before us is a summary in brief of the instru-
ment's use and practice.

The new catalogue of Messrs. Isenthal and Co.'s Electric
Heating Apparatus forms a not iminteresting record of the
various uses to which any householder can turn the electric
current supplied to him from the mains. l'~or readers of
" Ksowi.KDGH " the list is chiefly of service in detailing the
uses to which electric heating apparatus can be put in the
laboratory or the hospital, liut the limits to the purposes to
which electricity can be applied in the dwelling-house, the
kitchen, the workshop, and the factory are becoming enlarged
every day.

250

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

Conducted liij F. Shu.lington' Scales, f.r.m.s.

CoccidsLe.

WitK Notes on Collecting and
Preserving.

By Alice L. Emhli;tox, B.Sc.

[Continued from page 224.)

As regards the possible introduclion of the San Jose
into Europe, there is little cause for alarm, for the
climatic conditions and the character of fruit-growing
in this continent would make it hard for this scale ever
to become a serious factor here.

In the West Indies enormous damage is done to
crops of all kinds, and yet it is only within the last
decade of the 19th century that attention has been
paid to scientific work on economic entomology. The
sugar-cane pests in particular are responsible for a
heavy, regular loss to the planters ; investigations are
now, however, being carried on with a view to finding
remedies and controlling methods.

It is best to begin with measures of quarantine
against the introduction of new diseases. Preventive
measures ought to be adopted, for it is of enormous
importance if an outbreak of a disease can be avoided,
and it is only by a knowledge of the life-histories of the
pests that an attack can be predicted and controlling
conditions set up, such as, for example, alternation of
crops and trap-crops. If, however, the insect is
already established, then suitable remedial measures
must be applied, either by the direct use of poisons, or
by the indirect control through the presence of enemies
to the injurious insect. Fortunately for the horti-
culturist, Cpccidae have innumerable enemies, and the
problem of their control is largely solved by the action
of checks provided by Nature, such as birds, lizards,
bats, etc. Apart from these there arc the multitudes
of insects that prey upon Coccidae, either as predators
or parasites ; these tend, in a state of nature, to keep
the balance right, but this equilibrium becomes much
upset by the artificial conditif)ns set up in cultivated
countries where it is impossible to avoid this disturb-
ance of the influence of natural checks.

The Coccidae are hosts for numerous minute insect
parasites, as well as being food for the predaceous
ladybird beetles (Coccinellidae), which are among their
most important natural enemies. Among the many
thousands of minute Hymenopterous insects in the
world to which have been given the popular name of
" Chalcid flies," there is prob.ably no single family
that is of more interest and importance from an
economic point of view than that of the Encyrtidae.
The various species composing this family, like the vast
majority of Chalcid flies, live parasitic.illy in the eggs,
larvfe, pupse, and imagoes of other insects, and hardly
a single order of six-legged insects is wholly free from
their attacks. But in this family, and more especially

in the sub-family Encyrtinae, the species are of more
particular interest and importance for the economist,
since so many of them are found attacking and destroy-
ing Coccidae. The work on the development and life-
histories of these small creatures is of necessity very
minute, seeing that the hosts are usually only one or
two millimetres in length in the adult condition ; and
yet little can be done in the matter of encouraging these
beneficial creatures unless their life-cycles are well
known. Much of the work demands special methods
for the microscopic preparations. To illustrate this we
mav take the well-known brown scale on ferns and

5 tn.m.-

Fig. 1.

Fig.

2.-

Hg.

3.-

Hg.

4.-

Fig.

5--

Fig.

6."

Fig.

7--

EXPLANATION OF FIGURES.

Portion of Fern=frond attacl^ed hy Lecanium hemi^phacricum \ar.

/iltciiin, the Coccid being parasitised by Comyz in/vlix.

Egg before separation of the two masses.

Egg after losing the >olk = niass.

First observed larva with bifurcated tail. Length. '75 mm.

Larva showing spiracles.
— Prepupa in situ in the host, inverted position. /i^host;

/■ = parasite; pi plates.
-Cpmys iu'lUx. j, dorsal view. Length, 2 '.s mm,

awn by F. ShiUiugton Scales after dtai^'iiiris by Miss A. L. Embleion,

palms {Lecaitium hemisphaericum), which is parasitised
to an enormous extent by a minute Encyrtid (Comys
infelix). On a fern frond that has, say, 200 Coccidae
upon it, at least 190 of these will be killed by the
Comys. The female of this little fly measures 2.5 mm.
in length, and is black, with fuscous patches on its
wings. It is very curious that the male is extremely
rare, for whereas the females occur in myriads, the
males have only once or twice been obtained. In many
ways the life-history of this fly, as far as at present
known, is extraordinary and unique. The newly-

Oct., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

251

hatched female is found to have ovarian tubes in which
are eggs in various stages of development. The
youngest appear as oblong protoplasmic masses in the
tube ; later each of these masses in the chain becomes
constricted in the middle ; this becomes more
accentuated, until the egg assumes a dumb-bell shape,
the two parts being connected by a narrow neck, on
which there is a curious papillated valve or lip. Be-
fore this egg is laid in the Coccid host, one division
disappears, so that the egg as found in the host is an
oval body with a stalk which is found to iun to the sur-
face of the host's carapace, where its mouth is plugged
with some dark substance. The position of the para-
site egg is constant, being always dorsal and
posterior, a little to the left. In an allied form,
Encyrlus fiisicollis. Professor Marchal, of Paris, has
found that each egg gives rise to upwards of a hundred
embryos — the host being a caterpillar.

The larva; of Comys mfeltx passes through various
curious and complex conditions, peculiar chiefly for the
means it adopts for breathing ; the most startling being
that of the prepupa, where the host trachea' appear to
be themselves utilised and connected with the parasite
spiracles, and respiration goes on with the aid of these
borrowed tubes. Another curious feature is that the
prepupa seems to evolve a modification of the
Malpighian tubules of the larval form, and to get rid of
its spare uric acid in sacs containing rosettes of red
uric acid crystals, these sacs being applied to the sides
of the parasite's body, and left behind on the old pupal
skin when the fly escapes.

{To be concluded.)

NeNvton's Rings in Microscopica.1
Objectives.

A Correspondent sends the following note : —

" The modern method of testing optical curves on
glass to ascertain that they are accurately formed is by
means of what is known as proof plates. These proof
plates are made of glass, having ground and polished in
them the precise curve required. When the lens is
finished, the proof plate is put in contact with it, and if
the two are coincident — i.e., the two surfaces of the lens
and the proof plate respectively make optical contact —
coloured rings, known as Newton's Rings, will be seen.

" For immersion objectives used on the microscope,
the full power of the objective can only be developed
when specimens are mounted either in a medium of suit-
able refractive index, or are actually adherent, and in
optical contact with the under side of the cover glass. If
a slide of the diatom Pleurosigma angulatum be searched
over with a lens, say, of i-in. power and a deep eyepiece,
specimens will be found on which coloured rings — some
round, some elliptical, others of a nondescript shape —
will be seen, and it is in the centres of these appearances
that the frustule, or a portion of it, is in optical contact
with the cover glass. Having located this position, if an
oil immersion objective be used, immensely superior deii-
nition will be found to be obtained at this point of optical
contact than can be secured on other parts of the diatom
which may not be so close to the cover."

Cleaning Oil-Imnrversion Objectives.

Dr. Henri \'an Heurck calls attention to the advan-
tage of using saliva as a means of cleaning oil-immersion
lenses. He first cleanses the objective and slide with a
piece of old dry linen of fine texture, then moistens an
end of the linen with a little saliva, and gently rubs the
objective front with it, using a magnifier to see if the

cleaning is perfect. Owing to the slightly alkaline nature
of the saliva the cleaning is perfect, and practically instan-
taneous; and Dr. \'an Heurck says he has used this
method since 1878, and has never found it to fail, whilst
it keeps the front of his objcctixes as clear as when new.

Popular Microscopical Lectures.

I have received the annual list of lectures proposed by
the Extension Section of the Manchester Microscopical
Society for the ensuing winter. The scheme is so admir-
able and so well arranged that it deserves more than a
mere reference, lirielly, some 54 difl'erent lectures, selected
from the infinite variety of subjects dealt with by the micro-
scope and illustrated mostly by lantern slides, are arranged
to be given by some 20 members of the foregoing Society.
They are given to outside associations of all kinds who
make the necessary application, and, except in cases
where such associations are supported out of public funds
or are commercial speculations, are given free of charge
other than the reimbursement of actual out-of-pocket
expenses. The result is the bringing of scientific know-
ledge and information before those who would be unable
to pay large fees to professional lecturers, and the exten-
sion of the knowledge of microscopy and natural history.
Nowadays the microscope, whilst becoming daily more
and more necessary to the professional, finds many com-
petitors for favour with the amateur, and lectures of the
kind arranged by the Manchester Microscopical Society
should bring home to many the fascination of the micro-
scope as a recreati\e as well as educational instrument.
It would be well if the Quekett Club could see its way to
adopt a similar scheme ; in so large a district as is em-
braced by the Metropolis there should be no lack of
applicants for the services of its lecturers, and the result
could not fail to be of benefit to microscopy, and, inci-
dentally, to the Club itself.

Notes and Queries.

Wm. Watts, Bristol.

Total length, -055 to '06 mm. Head, '0045 mm. long,
•0025 mm. broad, •0015 mm. thick. Middle piece or body,
•006 mm. long and less than '001 mm. in diameter. Tail,
•045 mm. long and finer than the middle piece.

J. M. Dunbar, East Griquaiand.

I am sorry that I do not know of any good book dealing
with the microscopical examination of adulterated foods.
Such an examination is really a matter for the specialist, and
the microscopical examination would be only part of a wider
examination, chemical and otherwise. If you can read
German, perhaps Dr. Herman Hager's " Das Mikroskop und
seine Anweadung," published in Berlin, might serve as an in-
troduction. It could be ohtamed from Williams and Norgate,
Covent Garden, London, for about seven shillings and postage.
I wonder if any of my readers know of any other book ?
Microscopical Material.

Mr. W. S. Kogers has kindly sent me for distribution a
quantity of capsules of Funaria bygromdrica, the peristomes
of which make very beautiful dry mounts, and are curious
owing to the changes they undergo when wet and dry respec-
tively. I shall be glad to send a few of these to any reader
enclosing a stamped addressed envelope together with the
coupon appearing in another part of this issue. In case the
lids have not been shed they may be removed with a fine
needle, but great care is requisite.

' Communiciitions and enquiries on Microscopical matters arc invited,
and ikould lie addressed to F. Shil!ini;tun Scales, "Jersey, "St.
Barnabas Road, Cambridge.]

2\2

KNOWLEDGE & SCIENTIFIC NEWS.

[Oct., 1904.

The Face of the Sky for October.

By W. Shackleton, F.R.A.S.

The Sun.— On the ist the Sun rises at r,.i, and sets
at 5.37 ; on the 31st he rises at 6.53, and sets at 4.34.

Sunspots, facula', and prominences are fairly numerous.

The positions of the spots, &c., with respect to the
equator and poles may be derived by employing the
following table : —

Date.

Oct

The Moon : —

Axis inclined from N.
point.

Centre of disc, N of
Sun's equator.

26" 11' E.
26° 29' E.
26° 2' E.
24' 49' E.

6° 38'
6' 2'
5° 15'
4' 17'

Date.

Phases.

H. M.

Oct. 2 ..

d Last Quarter

I 52 p.m.

.. 9 ••

• New Moon

5 25 a.m.

,, 16 ..

D First Quarter

5 54 a.m.

., 24 ••

0 Full Moon

10 56 a.m.

., 31 •■

5 Last Quarter

II 13 p.m.

Oct. 8
.. 20

Perigee
Apogee

The only occultation of the brighter stars visible
before midnight is that of 96 Aquarii, magnitude 5^, at
7.49 p.m. on the 20th.

The Planets. — Mercury is a morning star in Virgo;
he is at greatest westerly on the i St., subtending an
angle of 17^54' W., when he rises nearly 2 hours in
advance of the Sun. The planet is in superior conjunc-
tion with the Sun on the 31st.

Venus is an evening star m Libra, but is too low down
in the S.W. at sunset to be suitable for observation.

Mars is a morning star in L50, rising about 2.15 a.m.
on the 15th.

Jupiter rises about sunset throughout the month, and
forms a very conspicuous object in the sky, looking due
E. about 7 p.m. The planet is in opposition to the Sun on
the^ i8th, when the apparent equatorial diameter is 5o"-4,
whilst the polar diameter is 3"-3 smaller.

At 10 p.m. on the 23rd the planet is in proximity to
the Moon, being only i'4 to the North.

The configurations of the satellites, as seen in an in-
verting telescope at midnight, are as follows

Day.

West.

East.

Day.

West. East.

423O1

1O432

41O3

4OJ3

4O213

421 O3

42O3 •

4203

413O2

43O12

43120

34r-J

432 U I

234 0 1

41O32

I031

4O123

C2I34

21O43

2I034

2O134

O40x©^'».,

3O24 •

3O124

312O4

32O14

3014

1O324

O1234

The circle (O) represents Jupiter; © signifies that the satellite is
on the disc ; • signifies that the satellite is behind the disc, or in
he shadow. The numbers are the numbers of the satellites.'

Saturn is suitably placed for observation in the early
evening, being on the meridian about 7.30 p.m. and
setting at midnight on the 15th. Throughout the month
the planet is nearly stationary in Cancer ; he is near the
Moon on the evening of the 17th.

The ring is widely open and we are looking on the
northern surface at an an.L,de of 16'; the polar diameter
of the ball is i6"-2, whilst the major and minor axes of the
outer ring are 4o"-8 and ii"'5 respectively.

Uranus is on the meridian about 4 p.m. and sets in
the S.W. about 8 p.m., near the middle of the month.
He is close to the star 4 Sagittarii.

Neptune rises about midnight on the last day of the
month. He is situated in the constellation Gemini, as
shown on the chart in the January number. The planet
is in quadrature with the Sun on the ist, and at the
stationary point on the nth.

Meteors ; —

The principal shower of meteors during the month is
the Orionids.

Radiant.

Date.

R.A.

Dec.

Characteristics.

Oct. 8-29
(18 to 20 maximum)

92-

If N.

Swift, streaks.

The Stars : —

About 9 p.m., at the middle of the month, the following
constellations may be observed : —

Zenith . Cygnus, Cepheus, Cassiopeia.

South . Pegasus, Aquarius, Capricornus, Fomal-

haut.

West . Lyra, Hercules, Ophiuchus, Corona ;
Bootes to the N.W. ; Aquila to the S.W.

East . Andromeda, Perseus, Aries, Pleiades ;

xVuriga to the N.E. ; Cetus to the S.E.

North . Ursa Major, Ursa Minor, Draco.

Minima of Algol may be observed on the 2nd at
5.14 p.m., 17th at 1. 19 a.m., 19th at 10. 8 p.m., and 22nd
at 6. 57 p.m.

Telescopic Objects; —

Double Stars; — 7_Arietis i'' 48"^, N. 18° 48', mags. 4-2,
4-4 ; separation 8"-8. Easy double, power 30 ; notable as
being the first double star observed telescopically.

7 Andromeda i"" 58™, N. 41^-52', mags. 2-i, 4-9, sepa-
ration io"-2. The brighter component is intensely yellow,
whilst the other is greenish blue. The fainter star is
remarkable for being a binary, the components of which
are now less than i" apart.

Nebul.e ; — ■

Nebula in Andromeda, easily visible to the naked eye,
and readily found by referring to the stars ft and v Andro-
medas. Seen with a 3 or 4 inch telescope, it appears to
be an extended oval, which is in reality composed of
spiral streams of nebulous matter.

(32 M.) Nebula close to the great Andromeda nebula,
and situated about 2^ to the south. It is fairly round,
and appears somewhat like a star out of focus.

(18 ^ v) lies about the same distance north of the great
Andromeda nebula that 32 M does south ; it is faint, but
large and elliptical.

KDouiledge & SeleDtifie fleuis

A MONTHLY JOURNAL OF SCIRNCR.

Conducted by MAJOR B. BADEN-POWELL and E. S. GREW, M.A.

Vol. I, No. lo. [new series] NOVEMBER, 1904.

r Entered at -i
LStalioners' Hall.J

sixpp:nce.

CONTENTS. See Page IX.

Indigo.

Hv I)K F. MOLI.WO I'l'UKl.V.

On"e of the oldest and most valuable of colouring
matters is indigo. Its properties and use were known
in India and Kgypt many years before the christian
era. It is described by Pliny, who says it was used
as a paint, and from what he savs it would appear
that the merchants of his time were not very much
better than some in our own da\s, l)ec;iuse the iiidiijo

Fig. I.— Indijjofera tinctoria.

was often adulterated with chalk or the excrements of
pigeons, and Pliny gives tests by which tiie pure pro-
duct might be known. It was not until the i6th
century that indigo \\;is introduced into luu'ope. Wiicn
it was first introduced, however, the sellers of indigo
encountered great opposition, and it was not until con-
siderably later that its use became :if all general.

It w;is the cultivators of wo;id who opposed its iiitio-
duction so violently ; they contended that the dye w.as
fugitive, an<l was also a pernicious ;md corrosive
|)oison. .So !^re:it \\;is their iiilliiciK-c .ind opposilicin

that Henry IV. of France issued an edict in which it
was made a capital offence to use or sell this [M'rnicious
drug, or dexil's food, as it w;is called. There was also
a statute in I'^ngland which prohibited the use of
indigo, and to this day that statute has, I believe, ne\'er
been repealed. The interesting point about the opposi-
tion of the woad cultivators is that uoad itself is a
variety of indigo, .and the blue dye with which the
ancient Britons anointed their skin, in pla<'e of w.irmer
clothing, was, in fact, indigo blue.

The indigo plant, /i/di go/era tinctona, is shown in
I'"ig. I, the woad plant, Uaii% linctona, in Fig. 2. As
;i matter of fact, woad is, to ;i certain extent, still
grown in Lincolnshire and in the south of France and

254

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

Hungary. It is not generally used for dyeing per se,
but is employed in the preparation of certain indigo
vats.

The indigo plant is herbaceous, and grows to a
height of from three to four feet, having a single stem
about half an inch in diameter. The land on which
the pl.'uit is grown is ploughed in October or Novem-
ber and sown with the indigo seed at about the end of
March or the beginning of April. The plant is of
rapid growth, and is cut for the first crop in about
the middle of June to the beginning of July — if 'the
weather has been propitious, usually at the earlier
date. The indigo plant is cut when it is just mature,
as indicated by the opening of the flower buds. After
about eight weeks a second crop is obtained, but the
yield of indigo is not so good as from the first crop.

Treatment of Plants.

We will not here describe all the different methods
which are employed for obtaining the indigo from the

tranquil the liquor is run off into the beating vats. At
this stage it varies in colour from a pale to a golden
yellow — the darker the colour the greater the yield of
indigo, but the light-coloured liquor, though yielding
less, gives a finer product. In the beating vat the
liquor is agitated by means of wooden paddles or
shovels, which are worked by hand. (In many fac-
tories the beating is now done by machinery.) As the
beating is continued the yellow liquor gradually
changes from green to blue, and finally solid indigo
begins to separate out. After the beating is finished
tlie blue fluid containing the suspended indigo is run
into the settling tank, where the indigo slowly falls to
the bottom, leaving the clear liquid above. The super-
natant liquor is then run off and the mud of indigo
[Jumped up into a caldron and boiled. This boiling
serves to prevent a second and destructive fermentation
setting in, which would both spoil the quality and the
qLiantity of the indigo ; it also serves to wash it and
remove impurities. After boiling it is run on to a

Fig. 3-

plant, but will merely give an idea how the process is,
in general, carried out. It must, in the first place, be
understood that the indigo does not exist in the free
state, /.(•., in the form of :i blue dve, but is there as
a ghicosidc — th.at is, combined with a kind of sugar
called iiidif^Incui, and this compound has first to be
split up before the indigo can be obtained.

The indigo plants after cutting are tied up into
bundles, and the bimdlcs carefully and tightly packed
into vats built of brickwork and lined with stone or
cement. When the vat is completely filled with the
indigo plant, beams of wood are wedged across the
bundles .and water is run in so as to completely cover
the plant. The object of wedging the bundles down is
to keep them below the water and to prevent them
being forced out when they swell, after the water has
been added. In a short time an active fermentation
sets in, which generally lasts from 10 to 15 hours ac-
cording to the temperature of the .'lir and the condition
of the plant. As soon as the fermentation becomes

large filter called the dripping \at, which may be from
JO feet long by 10 feet wide and 3 feet deep, the size,
h(>\\e\er, \ari.'s in clilTerent works.

.Alter draining lor about ^4 hours the pasty indigo
is placed in perforated cloth-lined wooden boxes and is
subjected to a gradually increasing pressure until no
more liquid runs out. It is then cut into small blocks
with a knife or brass wire, in much the same way that
cheese is cut ; the blocks being usually about 3 inches
square. The cubes of indigo are then placed on a
trellised staging covered with matting, which is con-
tained in open sheds and dried by exposure to the air,
direct sunlight being carefully excluded. The quantity
of indigo obtained from each fermenting vat varies
from 30 to 50 lbs.

I''ig. 3 shows in a somewhat picturesque manner
.111 indigo factory. A is the fermentation vat
with the pfxsts DD to hold the bars HH, which are
em|iIoycil to press down the bundles of the indigo
plant. \\ is the pipe through which the fermented

Nov., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

^55

liquor is run into tlie beating vat I>. The 1)catcr.s OM
arc held by tlie wooden fork X. C is tlie precipitating
tank witii the stops L, which are used for entering the
vat to clean or empty it. Q is the outlet for the
supernatant liquor. P is the well from which the water
is obtained with the trough ("iG leading into the fer-
menting vat. \' is the drying house in which the
staging for placing the indigo is shown at t.

It has already been stated that the indigo is not
found in the free state in the plant itself, but in the
form of a g/iicosii/r called indiain, which must be
split up in order to obtain the indigo. This spilling up
process is supposed to take place during the fermenta-
tion, but by the fermentation the indigo blue is not
directly formed, a jjroduct called indigo white being
produced. Xow indigo itsi'lf is not a soluble substance,
but indigo white is, and can be obtained from indigo
blue by taking away part of its oxygen. When, then,
this solution of indigo white is run into the beating
vat and agitated, air becomes mixed with it, and from
this it takes up oxygen, becoming converted into (he
insoluble indigo which is precipitated out.

As indigo blue or indigotin is insoluble in water, it
follows that it cannot be used directly as a dye without
being first made soluble. In order to dye with indigo
it is first converted into indigo white by means of re-
ducing substances — that is, substances which will take
away a portion of its oxygen. It is to aid in the
formation of indigo white that woad is .iddcd to the
vat, because it helps to set up a certain kind of fer-
mentation (butyric f rmentation). .'\ typical woad vat
contains from 20 to :;5 lbs. indigo, from li to 5 cwt.
woad, 20 lbs. bran or flour, 5 to 20 lbs. madder, and
24 lbs. slaked lime. The precautions necessary in
preparing the vat cannot be entered into, but the
operator must be skilful and experienced, the
art of preparing the bath often being handed down from
father to son.* When the vat is ready, which usually
takes from two to three days, the wool or other goods
are moved through the licjuid for from 20 minutes to
over an hour by means of a machine called a " hawk-
ing machine," they are then taken out of the vat and
exposed to air, by which means the indigo white be-
comes oxidised to indigo blue.

Indigo blue is one of the fastest if not the fastest of
blue dyes, and it is extremely stable to light and wash-
ing. The only fault it has is that it is apt to rub — that
is, to colour other substances blue which are in contact
with it, e.g., the linings of dresses, Kc. Very many
attempts have been made to substitute other dyes in
place of indigo, but it has always succeeded in holding
its own, most other dves lacking the rich hv..' and
bronzy appearance produced by indigo.

A few years ago the Indian indigo manufacturers
woke up with a start and found that there was an
artificial indigo on the market — that is, an article
which was made entirely by chemical means, and which
was not dependent upon the growth of a plant. This
artificial or synthetical indigo is made from products
obtained from coal-tar and has exactly the same con-
stitution and properties as the product produced from
the indigo plant.

The manufacture of synthetical indigo is one cf the
greatest triumphs of chemical science. For more than
20 years German chemists had been engaged upon the

* It must, of course, be understood that there are a great \ arietv
of methods employed in preparing an indigo bath .different ba'hs
being required for different kinds of work.

problem of how to prepare indigo on a manufai-turing
scale. I'rofes^c.r \()n l>ai-\er had .-ilready in 1S7S
discovered wh:it tlu constitution of indigo was, and
had been able to prepare it in small quantities in the
laboratory. But the problem of how to make it in
quantity and cheaply toolc more than 20 years to
elucidate, and the expenditure of enorinous sums of
money. Chemists all the world over were aware of
the facts, but the indigo j^lanters with a sublime in-
difference, unmindful of the fact that the great madder
industry, and the manufacture of alizarine from this
plant, had been abandoned owing to the advent of the
coal-tar colour industry, went their w;iy, Ire.-iding in
the old unscientific foofsti-ps ol Iheii' forelal hers - we
had almost said of the ancient I'^i^yptians — until tliey
were startled, as one of them pictures(|uely said, " hy a
l)olt from the bhie." Svntlietical indigo was a
realitv.

.\s might be expected, there is a great deal of con-
troversy as to the rival merits of natural and syntheti-
cal indigo. As ,1 mailer of fiict, indigotni, the bhie
c ;louring principal of indigo, w hether synthetically
prepared or obtained from the plant, is exactly the
same substance. But the indigo obtained from the
plant is not pure, as it contains besides other impiu-i-
lii-s small (|uantilies of indigo red, indigo brown,
,infl a gummy substrmce Called indigo-gluten, .-nid
the presence of these is said to impart a finer tone
to the dyed articles. On the other hand synthetical
indigo is quite pure, and the quality is always the same.
The methods of the indigo planters have been un-
scientific in the extreme ; now that the horse has been
stolen they are Ircking the stable-door and have called
in scientific adviix'. lm[)rovements in the manufacture
and better agricultural methods may, and probably will,
postpone the final triumph of the synthetical indigo ;
but it is to be feared that this once flourishing industry
will shortly be a thing of the past. It must be admitted
that during the list six of seven years, since the intro-
duction of synthetical indigo, the weather conditions
have made it very difficult for the planters to obtain
good crops, but even taking this into account the
following figures, taken from a recent issue of The
Times, are striking in the extreme. In 1894-5; there
were 1,688,042 acres under cultivation for indigo ; in
1502-3 the acreage had sunk to 574,654 ; the output of
indigo had during the same period fallen from 237,494
cwt. to 73,908 cwt. For the five years, 1899 to igoo,
the average export of indigo was 148,000 cwt. in
1903-4 it sank to 60,410 cwt., and the average price
from 203 rupees for the iimiiiid (Sj Uis.) to 14S
rupees.

A good deal of the land, at one time under culti\a-
tion for indigo, is now being planted with sugar, and
it is a matter of gre;it importance for India that as the
indigo is gradually forced out — we trust that the pro-
cess may be a slow one — its place should be taken by
some new product.

The subject of indigo cultivation and manufacture
has been brought before readers of " Kxowi.eooe " in
f)r(ler to bring home the absolute importance of scientific
knowledge and scientific researcli. If the Indian
inanufacturcrs had at the first sign of the appearance
(jf synthetical indigo, in 1878, exerted themselves to
understand the scientific problems underlying the pro-
ductif)n of indigo from the plant, we might not to-day
see a waning industry. One has only to look at the
wonderful progress of the beet sugar industry to see
what can be done when chemical and agricultural im-
provements are carried on side by side.

256

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

Modern Cosmogonies.

l:!y Miss Agnes Ci.erke.

XI. — The Procession of the Survs.

I'FiiiNfiMENA are fum-lions of lime ; .Tiid the form of
the funrtion has to Ijo clcterniincd in each partieuhir
case. That is what the liistorical method ct)mes to ;
.ind its use is prevalent and almost compulsory. \\'e
can no Ioniser be satisfied with ;i simple bird's-eye view
of the iinixerse ; our thoughts are irresistibly driven to
grope into its past, and to divine its future. Static
conceptions sulliced for our intellectual forefathers.
Thev aimed at establishing the equilibrium of things,
while we see them in a never-ending" flux. One .aspect
of them calls up the next, and that .another, and so on
<id infinHiiiii ; we cannot, if we would, balance our
ideas on the pivot of the transient present.

'Ihe immutable heavens of the ancients strike us to-
da\ as the inxention of a strange r.ace of beings. We,
on the contrary, see them with .Shelley as a " frail and
fading sphere" — a "brief expanse," the seat and
scene of change. The " fixed " stars long ago broke
;iwav from their nifiorings, and began to flit at large
llirongh sp.ace. Of late, a less obxious, more intimate
kiiul ol mobilifv has been attrilnited to them. (iroo\es
ot indi\idu.il dc\ el(i|iment seei'n prepared for them,
along which thev shilt as the tardy ages go bv ; and
since e\erylhing that grows must decay, the orbs cf
heaven, too, incur the doom of mortality. Modern
science, howe\er, has done much more than extend to
them the dismal philosophy of the phrase, " ioiii passe,
ii)!(t cassc, ioiif hissc." The grandiose enterprise has
been not unsuccessfully essayed of tracing in detail tile
progress of sidereal evolution, and of marshalling the
vast stellar battalions in order of seniority. This has
been rendered feasible by the disclosures of the spectro-
scope. Apart from their guidance, the tr.ack might
have been glimpsed here and there, but could never
have been laid down with any approach to definiteness.
Herschel found for it a icrm'tmis h quo In nebulae of
various forms, but attempted to pursue it no further.
We do not hesitate to run it on, from station to station,
right down to the Icnniiuis ad qiicm — not, indeed, with-
out the perception of outstanding difTiculties and in-
securities. They appear, howe\'er, to be outweighed
by a certain inevitableness of self-arrangement in the
visible facts.

The argument from continuity is that mainly relied
upon. An unbroken succession of instances is strongly
persuasive of actual transition, pro\ided only that a
principle of de\elopment (so to call it) may reasonably
be assumed as influential. A series of mineralogical
specimens, however finely differenced, does not suggest
the progressive enrichment of one original mass of ore.
In the stars, on the other hand, a species of vitality may
be said to reside. They are not finished-ofT products',
fnit self-acting machines. They are centres of energy,
which they dispense gratis, supplying the cost out' of
their ()wn funds. And Ihe process is not only obviously
torminabli', hut must be accompanied by constitutional
alterations, which might be traceable by'subtle methods
of enquiry. They are traceable, unless we arc decei\ed
by illusory appearances.

-Secchi's classification of the stars was unwarped bv
any speculative fancy. It was purely formal ; it aimed

only at providing distinct compartments for the con-
venient arrangement of a multitude of differently
characterised items of information. Then by degrees,
the close gradation of one class into the next came to
be noticed; the partitions melted away; the methodised
array showed itself to be in movement ; and the bare
framework took shape, under the auspices of Z(')llner
and Vogel, as a cosmic pedigree. The white stars
were set forth as the progenitors of yellow, yellow of
red stars ; ;md the insensibly progressive reinforce-
ment of the traits of relationship between the successive
types went far towards demonstrating some partial, if
not a complete, correspondence of the indicated order
with the truth of things. It has since been found
necessary to divide the first stellar class into helium
and -Sirian stars ; and here, too, essential diversity
shades off imperceptibly into likeness approximating
to identity. All the groups hang together ; the entire
scheme is on an inclined plane of change. Helium
stars, as the^■ condense, pass into Sirian, these into
solar stars ; which finally, reddening through the in-
crease of absorption, exhibit the badge of post-meri-
dional existence in fluted spectra. The finality of the
red st.age is, indeed, very far from being absolute, but
what lies Ijeyond is matter of conjecture.

There are se\eral good reasons for taking helium
stars to be the "youngest," or most primitive of the
amazing assemblage that sparkle in the vault o{
he.aven. The first is their affinity with nebulae. Every
star, perceived to be involved in folds or effusions of
shining haze, has yielded — if liright enough for profit-
able examination — a spectrum of helium quality.
I'urther, they arc rcmark.ably tenuous bfidies. It has
been ascertained with some definiteness, from the in-
vestigation of stellar eclipses, that helium stars arc
commonly, perhaps invariably, of far slighter consist-
ence than the sun. Radiation, however, is maintained
bv contraction ; hence, orbs at the outset of their course
must be, f)n the whole, the most diffuse. A third note
of youth is membership of embryo systems ; and this is
affixed very markedly to helium stars. One-third, cer-
tainly, probably one-half of those lately submitted to
trial by Professors Frost and Adams proved to have
spectroscopic companions. They are pairs believed to
ha\e been recently (in the cosmic sense) divided bv
fission. And this is an operation which must, we
should suppose, be undergone early, or not at all.

The spectra of helium stars are peculiar and sugges-
ti\'e. Thfise belonging to Miss Maury's earliest
groups — many of them visibly nebulous — bear next to
no traces of metallic absorption, showing instead lines
of oxygen, nitrogen, and of hydrogen in all its three
series. The conditions, accordingly, needed to produce
the " cosmic " modification of hydrogen arc realised in
these inchoate bodies. What those conditions actually
are, we cimnot tell ; vet it may be confidently surmised
that they will prove to be of an electrical nature.
Hydrogen resembles the metals in being electro-posi-
tive ; it collects at the negative pole during the electro-
lytic decomposition of water. There is, however, an
unmistakable tendency In primitive sidereal objects to
display absorption-rays of electro-negative rather than
of electro-positive elements. It is conceivable that hy-
drogen may be capable of altering its behaviour in
this respect; and that the molecules radiating the
Pickering and Rydberg series, in afldition to the more
familiar Huggins series, have, in fact, through some
corpuscular re-arrangement, assumed the electro-nega-
tive quality properly characterising a non-metallic
substance. The association of this form of hydrogen

Nov., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

with oxvyon and nitrotjeii in early helium stars todlcl
thus be more naturally related to the simultaneous
quasi-disappearnnce from them of the spectral badges
of metals.

I'he helium-line most distinctive of this stellar
family is situated well up in the blue. It appertains
to the same \ ibrational sequence with D ,, which is
also represented, at anv rate in Rigel, a somewhat
" advanced " Orion-star. Here, too, we meet a fairly
prominent magnesium-ray, lying below the blue helium
emanation ; while as yet iron is unapparent. Numer-
ous fine, faint streaks, due to its absorption, emerge,
however, when the -Sirian type is fully reached, and
they are mostly of the " enhanced " kind. When the
spark-discharge is substituted for the arc as the source
of illumination, certain lines in the resulting spectrum
brighten relatively to the others ; and these have been
distinguished by -Sir Xorman I-ockyer as " enhanced."
Now, the rule is strikingly prevalent that the absorp-
tion-rays in white stars arc of this class ; yet it can no
longer be interpreted as indicating for them an ex-
cessively high temperature. Rather, it would seem
that electrical conditions, still imperfectly defined, arc
in question ; and their gradual removal, or subsidence,
is, beyond doubt, largely instrumental in bringing
about the transition to the solar stage. The efface-
ment of helium-absorption is even more perplexing.
No sooner does iron begin to show than it vanishes.
There is still a faint trace of its " blue " line in \'ega ;
none survi\es in .Sirius.

In spectra of the solar type, two great bars of violet
light are stopped out by calcium ; otherwise, metallic
arc-lines predominate, while those of hydrogen are no
longer so powerfully emphasised as in white stars.
Moreover, the whiteness of the unveiled .Sirian photo-
spheres has become tinged with yellow owing to the
development of a shallow envelope partly impermeable
to blue rays. For this reason, the comparative exten-
sion of their ultra-violet spectra affords, for stars of
different types, no secure criterion of relative tempera-
ture. Sound in principle, it becomes inapplicable when
the unknown factor of general absorption comes into
play. The energy-curve of the solar spectrum as it is,
can be determined ; the energy-curve of the solar
spectrum as it would be if unaffected by general ;ih-
sorption, has to be constructed from inference. Rut
only bare photospheres give congruous results. Hence,
there are no valid grounds for asserting that .Sirius is
hotter than the sun, or the sun than Betelgeux. It
may be so, but the evidence at present available is
inconclusive. The appearances expounded in this
sense may bear quite different meanings.

The reasons for holding that solar mature into
.\ntarian stars are of the same nature, and of equal
cogency with those tending to prove their own de\clop-
ment from luminaries of earlier types. There is a
similar continuity of specimens. They can be ranged
one after another in an unbroken series, in which, as
we descend the line, primrose shades into orange,
and orange into red, general absorption arrests an in-
creasing percentage of the blue radiations, while
specific absorption becomes strengthened by dusky
flutings of titanium. Carbon-stars arc less easily
located. Dr. \'ogel regarded them as co-ordinate with
the Antarian class. The two varieties of red stars
with banded spectra descend, in his opinion, from the
common stock exemplified by our sun. Professor Hale
also favours this view, some attendant anomalies not-
withstanding. His photographs have certainly estab-
lished for carbon-stars links of relationship both with

the .\nt.iri;ui and the solar families ; vet the fad re-
mains indisput.able th.it the carbon type is, to ;i great
extent, isolated from all the rest. Tokens ol a genuine
migration towards it are lew and obscure.

The ultimate fate of both tribes of red stars cm only
be conjectured. .Most \;iry in brightness, some to the
\erge of periodical extinction ; ;ind variability m.iy be
a svmptom of interior dilapidation. The constitution,
however, of such objects is still enigmatical. They
appear to be exception;illv remote and inaccessible to
enquiry. \o indications have hei'ii g.ithered as to
their density or intrinsic light-power. \'ery little is
known about their moxcinents. They rarely form

binary combinations, and tliosi' that they do ft)rm are
almost always relali\ely lixed. .\o red star travels in
a computed orbit ; only one, >; deniinorum, ficcurs on
the long list of spectroscopic binaries. The revolu-
tions of this curious svsteni ought to prove, when
thf>roughlv inxestigated. of hi?;b interest and instruc-
tion.

Coupled stars offer special op[)ortunities to students
of cosmogony. They are ol)\iously contemporaries ;
they have started f.iir ; identical influences have acted
upon thetn ; hence differences in their standing can
only result from dissimilarities in mass or composi-
tion. It is comnionlv l.aken for granted that a body
cont.iinlng less matter than its fellow must dexclop
f.-istcr, and incur the fin.il f|uenching sooner. But .Sir
William and Lady lluggins ha\e adverted to the pro-
bability of the very opposite being the case. Powerful
surface gravity may, fhev considi'r, ser\e to hastc'ii the
tr.ansition from a .Sirian io ;i solar spectrum ; and we
should then have giant siuis liki- C'apella achanced in
type while at a very early stage of condensation.
This, perhaps, explains the remarkable spectral rela-
tions of contr.isted stellar pairs. AKv.ays, so far as
we vet know, the .Siri.an spectrum is yielded by the
lesser star, the mass of wlii<-h, judging by analogy,
must be small even below the proportion of its faint-
ness. It is true that the distribution of mass in binary
systems is often widely different from what might have
been anficipatetl. Certain pnr|)lish satellites, for
instance, of undetermined spci^tr.al quality exercise a
gravitative sway of surprising force. .Some results of
this kind, lately obtained by Mr. Lewis and others,
are likely to prove of fiimlamcntal importance to
theories of stellar exolution.

What we know of " dark stars " has been mainly
derived from the observation of stellar systems. They
are assumed to be the denizens of a stellar Hades, dim
wanderers amid the shades, who " have had their day,
and ceas<>d to be" as suns. In the "cold obstruc-
tion " of these viewless orbs the grand cosmical pro-
cession is held to terminate. Their presence attests
the downward progress of decay, and gives logical
completeness to the argument for de\clopment. ^'et
there are circumstances warning us against too full an
assurance th.at their status is really that of skeletons
at the fe.-ist of light. They are very frequently foimd
to be in close attendance upon brilliant white stars.
Thus intimately, if incongruously coujiled, they circu-
late, and compel circulation in brief periods, as mem-
bers of systems just, it might be said, out of the shell.
What are we to think, for instance, of the obscure
b)dy spectroscopically discovered to control the re-
volutions of the chief star in the Orion trapezium? It
is evidently comparable in mass with that imperfectly
condensed'luminary ; is it credible that it has already
traversed all the stages of stellar existence, and cooled
down to planetary rank? So violent an assumption

258

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

should, at anv r.ilr, not be made without due considera-
tion ; and wc ni.-iv more prudently hold our judgment
in suspense as to whether glol)es so circumstanced —
and they abound — sliould be regarded as effete, or as
abortive suns.

Speculations on the exhaustion of stellar vitality
have, however, lately become inextricably involved
with the complex problem of elemental evolution. A
dim inkling has been acquired of the working in the
universe of obscure forces, availing, we can just see,
to falsify manv forecasts. The theory, at least, of
the dissipation of energy needs important qualifica-
tions. Nor was it propounded by Lord Kelvin with
dogmatic certainty. He carefully noted the possibility
that in " the great storehouses of creation " reserves
of energy might be provided by which the losses in-
curred through radiation could be, wholly or in part,
made good.* The anticipated possibility is, perhaps,
realised in the phenomena of radio-activity. But if
we enquire how, we are met at the threshold by diffi-
culties connected with the origin of helium. Helium
appears to result from the disintegration of radium, its
generation being accompanied bv the setting free of
enormous quantities of energy. Its copious presence,
then, argues long-continued and lavish expenditure of
heat and light. Yet it is as a constituent of highly
primitive orbs that it is chiefly conspicuous. Gaseous
nebulse, too, include immeasurable supplies of it, while
it is incompatible with whatever we seem to know
about them to suppose that radium at any time entered
into their composition. In truth, however, the genesis
of the elements has not yet been made the subject of
coherent speculation. Current ideas regarding it im-
ply a double course of change, by aggregation first,
and subsequently by disintegration. .'\nd this should
give us a two-fold series of elements. On one side,
there should be fixed sur\iyals of the advancing pro-
cess, on the other, products of decomposition, continu-
ously evolved, and even now accumulating. If the
claim of helium to take rank among these last should
be finally established, our conceptions of the nature
and history of nebulce might have to undergo a strange
in\ersion ; but the outcome of the researches in pro-
gress is still uncertain, and may be far off.

It is, however, quite clear that the electronic theory
of matter supplies no genuine explanation of the source
of energy in the universe. What is given out when
the atoms go to pieces must have been stored up when
they were put together. Whence was it derived?
This is_ the fund.imental question which underlies
every discussion concerning the maintenance of the
life of suns. It is unanswered, and probably un-
answerable.

•Thomson and Tail, Natural Philosophy, Appendix E, p. aq,
edition 1S90.

Physiology.— Mr. E. H. .Starling is to be congratulated on the
little •' Primer of Physiology" (John Murray). It is an attempt
to convey with as few technic.1l terms as possible the leading
ideas which make up present-day physiology. That is rather
a formidable task in a book of some thirty thousand words;
but Mr. Starling not only does succeed in conveying a very
clear idea of the way in which the normal processes of life are
carried on, but does it without the sacrifice of any essential
fact, and with— as for example in the chapter on serums — the
illumination of the latest theory.

Racre Living Animads
in. London,

By P. L. .Sci.ATER, Dr.Sc, F.R.S.

III. — Grevy's Zebra.

The herd of Grevy's zebra in the Zoological Society's
Gardens in if,o3, consisting of a male and four
females, was, in my opinion, one of the finest groups
of the class of mammals ever shown by the Society.
Unfortunately, both the males have lately died,
but an aduit and three younger females still re-
main, and exhibit the form and markings of_ this
beautiful animal — the most remarkable of all the living
members of the Equine Family.

.^s to the perfect distinctness of Grevy's zebra from
all the various forms known as Burchell's zebra and
its other congeners there can be no longer any ques-
tion. The larger size, broader ears, white belly, and
entirely different style of banding render this splendid
anima! recognisable at first sight, as will be seen by
Mr. Goodchild's drawing, which has been taken from
the adult female of this species placed by her late
Majesty Queen Victoria under the care of the Society
in 1S99, and still living in the Regent's Park.

Although probably well known to that most ob-
servant naturalist, Emin Pasha, who appears to have
met with this animal in Latako in the Equatorial Pro-
vince of the Sudan, the first specimen of Grevy's zebra
to arrive in Europe was a living example, sent as a
j' resent by the Emperor Mcnelek in 1882 to M.
Grevy, then President of the French Republic, and de-
posited in the Jardin des Plantes.* This was long
before the " Fashoda incident," when France, in the
eves of the Abyssinians, was more potent than
lingland. On hearing of the arrival of this novelty I
hurried over to Paris to inspect it, and was rather dis-
appointed to find the zebra already dead and an in-
habitant of the Mammal-Gallery of the Museum
d'Hisiflire Naturelle. I saw at once, however, when I
came to examine the specimen, that it was widely
different from all other known zebras, although I had
some little difficulty in persuading my friends at the
Zoological Society that such was really the case.

in iSgot I was .able to give the Zoological Society
further evidence of the distinctness of Equiis grtvyi
from the other zebras, and to show that its distribu-
tion extends from the southern frontiers of Abyssinia
into Somaliland. .\ flat skin, obtained for me in
Western Somalilrmd by Herr Menges, through the kind
intervention of Herr Carl Hagenbeck, was found to
belong unquestionably to Eqtiiis grevyi, which, in fact,
appears to be the only zebra met with in that country.
In his excellent work on Somaliland I Capt. Swayne
gives us the following particulars concerning his ex-
periences with this animal : —

"Grevy's zebra, although first described by the
French, had been shot in Somaliland by Col. Paget and
myself on our expedition of 1893. I found it at Durhi,

♦ See Proc. Zool. Soc, 1882, p. 721. The specific name Eqinis
grevvi was based on this specimen by tlie late .-Vlphonse Milne-
Edwards (La Natiiie, No. 474).

+ See P.Z.S., 1S90, p. 443.

; "Seventeen Trips Through Somaliland Py Capt. H. G, C.
Swayne, RE. ; I.-mdon, 1892,

Nov., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

259

in Central Ogaden, between the Tug Fafan and the
Webbe, about tliree hundred miles inland from Ber-

bera, and shot seven specimens This zebra is

very common in the territory of the Rer Aiiiiiden and
Malingur tribes. The country there is covered with
scattered bush over its entire surface, which is stonv
and much broken up by ra\ines, the gener.il elevation
being about two thousand five hundred feet above the
sea-level. The zebras which I saw (probably not more
than two hundred in all) were in small droves of about
half a dozen each, on the low plateaux covered with
scattered thorn-bush and glades of t/ttra-grass, the soil
being powdery and red in colour, with an occasional

Rurchell's zebra in great herds among the mountains
of the Boran country, but no Gicvy's zebra until Lake
Stephanie is reached. Here you lind the ranges of the
two species overlapping to a certain extent, but about
Lake Rudolph I met oni\' with Gn'vy's zebra."

It is probable, therefore, that the (iirvy's zebras
l)r(night from Abyssinia wi-i-e oijl.iincd from tin-
country north of l.ake Rudolph.

The Grdvy's zebras exhibited in the Zoological
Society's Gardens have been altogether six in number.
The first p;iir, which were presented to (Jueen X'ictoria
by the Emperor Meneiek, arrived on .August 14, iSgg.
The ICmpcror subse(|uently sent two females of the

(jrevy's Zebra.

{From an Adult Fciiitile in the GarJens of the Zoological Society of I.onilnn.)

outcrop of rocks. In this sort of country they are
very easy to stalk. I saw none in the flats of the
Webbe valley, and they never come so far north as the
open grass plains of the Haud, Durhi, south of the
Fiifan, being, I think, their northern limit."

.About the range of Grevy's zebra on the Abyssinian
side, and whence the living animals sent to Europe bv
the Emperor Menelek were obtained, we have no such
exact information. In 1895 the well-known American
traveller, Dr. Donaldson Smith, gave us the following
account of the distribution of Gievy's zebra so far as
he was accjuainted with it : —

" Commencing 20 miles east of the .Shebeli River,
the range of Grevy's zebra extends about 120 miles to
the west ; it is limited by the second and eighth degrees
of latitude. On passing the Juba River you find

same zebra to King l^dward, which were placed under
the Society's care on July 12, 1902, and in the follow-
ing year a fine young pair was presented to the .Societv
by Lieut.-Col. Sir j. L. Harrington, K.C.B., H.M.'s
1-Lnvoy at the .Abyssinian Court Both the males have
been unfortunately lost, and the present stock in (he
Society's Gardens consists of females only. There are
also one or more females of Grevy's zebra in M.G. the
Duke of Bedford's menagerie at Wohurn.

The form of the group of Burchell's zebras that
extends furthest nf)rth, and is probably that which Dr.
Donaldson .Smith alludes to as in some places " over-
lapping the range " of Grevy's zebra is commonly
called Grant's zebra (Eqtius grantt). There is one
example of this zebra also in the Zoological .Society's
Gardens at the present time.

26o

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

NaLtvirocl Mvimmies.

Bv Francks a. W'ei.hv.

I\ the ancient parish church of \'enzone, situated in the
extreme north of Italy, some twenty miles above Udine,
at the bifurcation of the valley known from time im-
memorial as the Canale di Ferro (long the high-road to
Germany, and still to Carnia — up which, on the one
hand, the railway passes to the Austrian Frontier at
Pontebba, while, on the other, the historic River
Tagliamento flo^s down from the Carnic Alps to the
plain of Friuli) are thirteen tombs that possess the
natural property of mummifying, or, more properly,
desiccating, the bodies deposited in them. In the course
of one year or less, more certainly in two, such bodies,
clothed and placed in wooden coffins, are as a rule
completely transformed, and become dry and light, and
vellowish-grey in colour. The skin remains intact and
resembles parchment ; the bones are perfect, held in
place by the dried ligaments and articular capsules,
more or less covered with muscular and tendinous
fibres, which, with the nerves and blood-vessels, ad-
here together in a desiccated mass. Teeth, hair
(beard, eyebrows, eyelashes), and nails are all pre-
ser\ed in astonishing perfection, the fluid parts of the
body alone disappearing. When extracted from the
tombs, the mummies .'ire covered with a layer of dark
yellowish nioidd or fungus, that disappears little bv
little, and the cutis, at first blackish and flexible, be-
comes a pale yellow, in colour and texture exactly like
sheepskin. Thev are extremely light in weight, vary-
ing from three to six kilograms.

The process is not effected with equal rapidity in all
cases, and fails altogether in some instances (in which
ordinary dissolutiftn then takes place) — the reasons for
this not having been discovered. The tombs in the
church are twenty in number, but only thirteen, as
said above, have this property of desiccation, and of
these, again, seven succeed much better than the
others. All are constructed with brick walls, cemented
with common lime, and closed hermetically with slabs
of stone or marble. It is, however, a curious fact that
the process is not inhibited by the free admission of
air and water, one of the most perfect mummies having
actually been discovered floating in water. In dimen-
sion the tombs are about i metre 90 in depth, bv 1.50
in width, and 2.00 in length. The inscriptions on the
covers show that they belonged for the most part to
ancient and noble families of \'enzone, but three at the
foot of th" choir deser»e special mention. The first
held the remains <T one Boleslaus, Duke of Schlesia,
who had, perhaps, returned from the Crusades in the
suite of the Emperor Conrad III., in 1149 ; in another
rested .\goslino, Prior of Briim in Moravia, and Bishop
of Concordia, \'ic;ir Patriarchal, who on June 22, 1392,
was slain on the banks of the Tagliamento bv Nicoi^i
Savorgnan for complicity with the Patriarch in the
murder of Federico .Savorgnan, his kinsman ; and the
third must have covered a pilgrim, since the stone is
inscribed with the words, 'hie jaccl Laiircntiiis de
Bacia, and a rude sculpture of a hand holding a
pilgrim's staff.

The first mummy was discf>\ered in 1^37, when, in
rebuilding the Chapel of the Rosario, a "sarcophagus
inside the church (now^ standing outside the Xorth

door) was opened. ^^■ithin it was found a coflfin in good
preservation, and within that a handsomely-clothed
mummv also in good preservation. The tomb bears
the arrns of the Scaligeri, with two sculptured angels
carrying away the soul of the departed. From its
velvet wrappings, the mummy presumably belonged to
this familv. Unfortunately all the ancient records of
X'enzone were destroyed by fire in 1547, so that no
previous documents exist to throw light on this, and,
perhaps, earlier discoveries. The Gobbo (Hunchback),
as he is called, is still preserved, and, like the rest of
his companions, shows no sign of perishing from ex-
posure, though he has suffered considerably from the
rough handling of injudicious visitors. For many

ij^-

years no more was thought of the phenomenon, until
in the i8th century other similar mummies were dis-
covered in other tombs, after which a number of
successful experiments were made (eighteen up to
1S31, twentv-one after that date), until burial in the
church was prohibited for sanitary reasons. The last
two were exhumed in September, igoi. The
\'enzonese frequently go to look at their relatives, and
take pride in recalling familiar characteristics. The
broken arm, e.g., of one of the latest subjects, is
demonstrated with much satisfaction.

Xapoleon I. visited V'cnzone in 1807, and proposed
to make .in Imperial Necropolis in the little mountain
city, but upon his downfall the project was abandoned.
Francis I. of .Austria, in i8ig, and Ferdinand I. in
i<S4.S, also visited this strange cemeferv.

The thirty-two extant mummies are ranged round

Nov., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

261

the wall of an adjacent chapel, the ancient Oratory of
S. Michael — a grim and ghastly company. From
waist to knee they are clad in a decorous white kilt or
loin-cloth, the ecclesiastics being somewhat grotesquely
distinguished by liirettas. Rosaries are still clutched
in some of the poor desiccated fingers ; the hands of
one arc clasped over his bre\ iary. Women as well as
men are there ; the erstwhile notion that cmly the male
sex were susceptible of mummification having been
exploded by the discovery in 1826 of a very perfect
female subject, who had died of typhuS in 1816. The
smaller number of female mummies is doubliess due
to the fact that these tombs were usually reserved for
priests and persons of distinction in the comnumity.

It is notable that the phenomenon occurs not only
in the parish church, but also in the Chapel of S.
Catherine, a little to the east of \'enzone, where is one
tomb in which the remains become completely trans-
formed, and where the body of Don Felice Tavoschi of
Tolmezzo, the well-lo\ed pastor of Venzoiie, who
succumbed to cholera in 1855, is preserved to this day
by the affection of his people. .At Ospcdaletto, too,
three miles nearer Gcmona, five similar tombs aie
known to exist in the ancient I'riory of the Santo
Spirito. And animal remains, in a perfect state of
desiccation, have been picked up upon the plain of
Portis, three miles above \'enzone, on the road to
Tolmezzo ; so that it would appear as though for a
radius of some six miles round W-iizone, human :md
other animal remains, buried in the earth, or more
particularly in the tombs of the churches, are in this
singular manner more or less frequently converted into
mummies.

The phenomenon has naturally gi\en rise to much
scientific discussion, though it appears still to be an
unsolved problem. The latest writer, Dr. Pare (1S70),
exclaims with pardonable sarcasm that " had such a
rare phenomenon occurred within ig Italian miles of
Paris instead of Udinc, the French .Academy would
have appropriated it, would have subjected it to most
searching examination, and would have published
monographs of Atlantean magnitude, which, in pro-
portion as they rose in price, would be treasined in the
most illustrious libraries."

Dr. Ciconi in 1829 suggested that the desiccating
agent might be the calcium sulphate, which, in a more
or less anhydrous form, and mixed with calcium
carbonate, constitutes the soil of Vcnzone and Ospeda-
letto. This comes from the limestone debris of the
Carnic Alps brought down by the Fella and the Taglia-
mento. He points out that anhydrous sulphate of
lime, which absorbs water avidly, was the principal
substance used by Hunter in his celebrated [)rocess for
preserving the human subject, and suggests that the
imperfect desiccation occurring in some of the tombs
would be due to their ha\ing been excavated abo\e or
below the beneficent layer. Marcolini in 1S31 put for-
ward a hypothesis that the acidification of the soil by
hydro-carbo-phosphatcs might be the cause owing to
which the natural processes of corruption were in-
hibited. Stringer! maintained the same idea a decade
later. But Dr. Zecchini in 1861, and Dr. Pare (Direc-
tor of the Hospital at Udine) in 186S-70, independently
brought forward the theory that the desiccation was
produced by a parasitic mould, TJypha bnmbastica Fcrs,
which absorbs the aqueous humours of the body, and
induces mummification. This mould is invariably pre-
sent on the surface of the mummies, covering them
here and there, in greater or less profusion, and per-
sisting for a long while after their exhumation and

exposure. Hul Ijy previous observers it had been re-
garded as the cjli-ct and not as the cause of the
phenomenon. It is ;i micioscopic parasite, composed
ol white fungoid tlocculi, aTialogous to the Hotrytiis or
parasitic fungus that produces " calciiio " in the silk-
worm. In 1870, Dr. Pare made a series of experiments
in which he succeeded, bv sprinkling various animal
remains with Hy[)ha from the X'enzoiie mummies, iii
oljtaining successful preser\ ations of IVogs, eels, antl
cats; while, on the contrary, he failed with lishes
(apparently on accoimt of the scales), and with a (.V-:n\
lamb (perhaps because the Hypha, nourishing itsell
upon the fatty humours of the wool, was luiabie to
attack the body before it underv\eiit decomposition).
He explains the successes and failures in tlic Iniinan
subject by the conflict between the Hypha nr pirserx.i-
tive agent and the processes of ck'comjxjsition, the one
or the other predominating according to circumstances.
It is obvious Iroin his experiments that the phenomenon
is common to all animal remains, and is |jv no means
peculiar to the human l)od\.

Other similar mumjiiies ha\e been lound in the
Cathedral of Tolouse, in the Church of S. Michael
in Dublin, and in the .'mcient Servitc Monastery
of Monte-all-Croce near Uonii ; lint tlicv are less per-
fect than those of Venzone. A par.illel has also been
sought in the mummies found in the burning sands of
.\r;ibia, but at Venzone the phenomenon cannot be due
to heat, as the temperature of the tombs is very low.
Nor is it produced by the action of cold, otherwise the
mummies would decompose at the lem[)erature of the
air, like those of the Arctic Regions. The\' arc im-
pervious to the action of air, and e\en of water ; while
the desiccating and preservative agent is able to resist
even such potent forces as the putrefactive processes
of typhoid fever.

Note. — The probable action of a parasitic finit^us upon the
"Venzone Mummies" is borne out bj' Mr. Massie's article in
■' Knowledge " for October, 1904, in which he mentions the
Hutrytus, by which the silk-worm is completely desiccated, or
calcified —a too-familiar phenomenon in the silk-worm districts
of Italy — and otiier forms of " nuimmifyin^' " fungi.

Further information as to the probable cause of the plinio-
menon at Venzone would be welcomed by the writer, wlio
failed, during a prolonged stay at Udine last year, to obtain
any reliable scientific explanation of it.

Explosion of Starrs.

By Pkoiessor A. W. BickeI'ITo.n'.

Do stars explode? Are the oljservers of Lick and
V'erkes correct when they said that Nova I'ersei had
become a nebula that was expanding at such a rate
that no theory of its origin was tenable, but that a
star had exploded, been converted into gas, and blown
at a velocity of thousands of miles a second to spread
itself throughout the entire universe?

Is it conceivable, with the known laws of matter and
energy, that a force can be generated great enough
to blow a star to pieces? A calculation shows that
were the entire star an explosive, it would have to 1)(;
a score of thousands of times stronger than dynamite.
Is there in Nature anything in which such a store of
energy exists? This tjuestion must imdoubtedly be
answered in the affirmative, and the source of the
energy is the attractive force of gravitation. The force
with which the sun attracts matter, and the enormous

262

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

distance through which this force extends, gives us an
energy so great that, without any original motion, a
particle falling from the nearest star upon the sun
would reach it with a velocity of three hundred and
ninety miles a second. This \elocity would possess
an energy hundreds of millions of times greater than
that of an express train, and the temperature produced
li\ the stoppage of the motion would excel that of an
L'lectric furnace a score of thousands of times.

Hence, in the collision of suns we ha\e an agent
that may generate energy sufficient to cause the sun to
explode, but so enormous is the mass of a sun, that
the energy of collision has been shown to be too small
to blow the sun into a nebula ; but the probabilities of
a direct, complete collision between suns is small in-
deed. Any original motion or any attraction of other
bodies acting during their fall towards one another,
would tend to makcthe impact of a tangential charac-
ter, and it is upon tlie study of tangential impact that
the solution of our problem depends. The velocity
with which two suns would sweep past one another
would be so great tiiat a slight graze would not stop
them. They "would tly past one another, scarred by
the encounter ; but the portions that lay in one
another's path, and that did actually come into collision
would be swept from the reniaintler, would coalesce,
and would form a new Ijody in space. The
tremendous motion would Ijc con\erted into heat, and
the mass of the new hod\ , if the graze were not deep,
might be so small that the explosi\e pressure produced
would blow it into a nebula that would continue to
expand with an enormous \elocity, and every particle
be finally dissipated into free space ; in some cases
leaving the very universe itself.

It is thus seen that the numbers and distribution of
the stars must, on the demonstrated laws of Nature,
produce an explosion ; and it is highly probable that
all the so-called temporary stars that have appeared at
intervals in the heavens, usually increasing in brilliancy
for some hours, or a day or two, and then gradually
disappearing, are caused by p.artial impacts of stars
or, in most cases, of dead suns. For all these bodies
have similar spectra crossed with doubled lines, the
one showing recession, and the other approach,
indicating the two scarred suns that have struck one
another; whilst the brilliant continuous spectrum
seen in all new stars, for some time after the outbreak,
is due to the mass of flaming gas that must expand at
the rate of some milHon of miles an hour.

The \'elocity with which these bodies pass one
another would cause the impact to be o\er in an hour
or less ; and in this time a body is produced with a
higher temperature th.an that of any ordinary star.
'I'his IjrilHant body would soon expand until the globe
of (ire would be thousaiuls of limes the \olume of the
sun.

Hence we need not be surprised ihat Tycho Rrahe's
new star grew to be more brilli;mt than Jupiter, even
more briili;mt llian \'enus at qu.'idrature ; so intense,
in fact, as to be \isiljle at noonday. Nor need we
wonder at its disappearance, for the flight of its myriad
molecules all travelling from the point where the ex-
plosion occurred, would rapidly tend in their radial
outrush to become ])arallel, and the molecules con-
sequently cease to strike one another save at intervals ;
and as molecules only radiate immediately after en-
counters, it is obvious that, as these encounters become
fevyer in number, the luminosity of the mass would
lessen and go on lessening until it was absolutely lost
to vision.

Herschel has told us that the only possible explana-
tion of the character of the many planetary nebula that
he discovered was that they were hollow shells of gas.
Every stellar explosion that is produced by a partial
impact must result, at one stage of its history, in a
planetary nebula that may be permanent or evanescent
according to the attractive power of the new body as
compared with its temperature.

Thus evanescent planetary nebula would be produced
by slight grazes, whereas a deeper graze might pro-
duce a permanent planetary nebula, and still deeper
grazes result in a large ratio of the molecules being
attracted back, and producing a star in the centre of
the nebula. Examples of this arc comparatively
numerous in the celestial vault.

.So that our observers were doubtless right in the
conclusion they came to that " Nova Persei " was a
celestial explosion in which a star had been blown to
pieces. And this fragment of the study of impact
shows how important an agent impact is in astronomi-
cal evolution, for it must be remembered that all kinds
of impacts may take place, from a mere graze up to
a complete impact. Impacts may take place between
dead suns or lucid stars. They may take place between
meteoric swarms, or between star clusters. The impact
of nebuke may range from a mere graze through deep
cuts, up to entire coalescence ; and every form of im-
pact save direct centre to centre must result in rota-
tion, and obviously furnishes an explanation of the
spiral character of so many thousands of nebulae.
.Again, such vast bodies as the two magellanic clouds
may be approaching one another, and after countless
ages may imp.'ict, and should they strike deep enough
into one another, coalescence of a whirling character
would result, giving a galaxy of stars of a double
spiral character, and spreading the poles of the ring
with masses of nebulous matter, a configuration that
exactly corresponds with the structure of our universe,
and hence may we not ask the question, " Is not our
visible uni\erse a result of the coalescent impact of
two previously existing universes, and if so may not
such cosmic systems exist in endless number through-
out the infinity of space? "

.Such are the lofty conceptions that develop them-
selves from the study of impact, carried fearlessly to
its legitimate conclusions.

PKotogroLphy.

Pure and Applied.

By Chapman Jones, F.l.C, E.C.S., ivc.

The Use of Colour Screens n'llh a Loiu Sun. — In the
September number I wrote: — "As the sun gets low
the daylight gets markedly more yellow, and we have
from time to time been instructed that the excessive
blue sensitiveness of gelatino-bromide plates becomes
so far negatived on account of this change, that it is
not necessary to obviate it by the use of a yellow or
orange-coloured screen. Whether or not this is so
depends on what the photographer wants. If he seeks
to photograph an evening effect as if it were lit by
such light as given by the sun only when he is high
up in the heavens, while the general effect is such as
can be obtained only when he approaches the horizon,
then he may omit the coloured screen. But if his aim
is to photograph the scene before him as it is, there is

Xov., 1904]

KNOWLEDGE & SCIENTIFIC NEWS.

263

as much need for the yellow screen at sunset as at mid-
day." I learn from the coluiims of a contemporary
that this passage has " sadly troubled " him and at
least two of his readers. This 1 regret, but would
suggest that those who wish for further explanations
of any matter in these chapters would do well to ad-
dress our editor, or me through him, as then lliey will
be certain of getting such assistance as I can render.
I cannot undertake to read other journals for the sake
of tinding comments on what I say here.

The point of the above extract is that the excessive
blue sensitiveness of the plate is an error of the plate,
and if not compensated will produce its effect in a
photograph taken when the sun is low as well as when
the sun is: high. I'hat if the partial loss of blue light
as the sun gets low (the light becoming yellowish by
reason of this loss) is accepted as compensation in
photographing late in the day, ami the yellow screen is
discarded, then the colours of the objects photographed
will be rendered in the photograph as if they were lit
by a midday sun and the yellow screen were used. It
would be an anachronism to represent an evening .scene
with a low sun as if the quality of the light were such
as we get only with a comp.iratively high sun — Ijut we
are so used to errors of this kind in photography that
our sense of criticism is dulled. The error is in the
plate, and whenever the plate is used the screen should
be used if it is desired to represent the scene as it
appears when photographed.

Indoors it is possible to use a yellow light instc.id of
a screen, and it will be found that ordinary gas or
lamp light will compensate the plate error to about the
same extent as a yellow screen that requires the ex-
posure to be increased four or six times. Rut the
photograph taken by gas light will not render colours
as they appear by gas light, but as they would appear
by a whiter light more similar to daylight. If one has
a colour screen that is made to properly compensate
the errors of colour sensitiveness of the plate, then the
screen should ahoays be used when it is desired to
render colours with the tone values as they appear at
the time of photographing them.

T/ie Royal I' holographic Society's Exhibition. —
Although the relation between the dates of the opening
of this exhibition and the publication of this journal
renders it impossible to refer to any of the exhibits
until after thej' have ceased to be on view, there arc a
few points connected with the scientific and technical
section that it may be of interest to refer to. The
making of a series of consecutive photographs of
changing objects at suitable and st.ited intervals so as
to show the character and progress of the change, is
an application of photography that has much to com-
mend it. There were several examples of such work
this year as there have been in previous exhibitions,
the most notable being a series of seventy photographs
by Mr. W. M. Martin, showing the embryology of a
chicken. Of this series some were taken by trans-
mitted light, some by a combination of transmitted
and reflected lighl, and one by Rontgcn rays ; that is,
the illumination was varied in order to best show the
required detail — a consideration in such work that (Iocs
not always receive the attention that it might. The
application of Rontgen ra3's to the demonstration of
internal and hidden structures was exemplified in a
novel way by Dr. Rodman in a number of radiographs
of Mollusca. The internal anatomy of each shell was
shown with surprising clearness, and the systems of
complex and superposed curves often formed figures of
great beauty.

A portrait taken with ultra-violet radiations obtained
by means of the screen devised by Professor R. VV.
\\'o(_>(J was shown by .Mr. lidgar .Senior. It merely
demonstrates in a striking way the possiljility ol photo-
graphing an object quite in the dark. The portrait
was very passal)ly focusseil, considering that the ob-
ject and the image were both invisible, anti that lenses
are not corrected for the purpose of using them in this
eccentric manner. A telepholograph of the upper [j.irt
of St. Paul's Cathedral, by Mr. .'\. 1"^. .Stiiith, was an
excellent production from a technical point of view.
I'he magnification was twenty-lour diameters, and as
one thousand feet of London atmosphere intervened
between the object and the camera, it was an excellent
illustration of how an almost hopeless task may l^e
siiccessfidly accomplished by selecting suitable ct)ndi-
tions. riifjse interested in Mr. J. Iloit Player's in-
genious method of copying engra\ings, tVc. (Player-
type), will be glad to know that Mr. Player showed
some very satisfactory enlargements produced from
negatives obtained by his process.

Coloured I'llins. — The necessity for controlling the
character of the light that may be available is ever
present with the practical photographer, 'i'oo t)ften he
lias to be content with some commercial article made
for a e|uite different purpose that happens to be sulfi-
ciently near to what he requires to be serviceable.
Bookliinders' cloth, coloured tissue paper, hock bottles,
and other such makeshifts, are still commonly used,
though in a few cases the demand has been met by
more suitable and specially-prepared media. A further
step in the right direction has recently been made by
Dr. G. Krebs, of Offenbach-on-Main, who has put
upon the market a considerable assortment of tough
coloured films, specially made for the various jjurposes
for which coloured media are required. They are
known as the " (Jeka llexoid filters." Man\', if not
all of them, have been prepared from formula;
suggested by Or. Miethe. I have examined several,
and can confirm the statement that they do, practically
speaking, absorb that [i.-irt of the spectrum that they
are stated to in the description of them, ;md that they
form such series as are most generally neetled. There
are a yellow and three red films for dark-room lamps,
transmitting the red and green, the red alone, the red
beyond wave-length 610, and the red beyond about C,
respectively ; yellow films of three depths for use with
orthochromatic plates ; blue, green, ;ind red filters for
three-colour work, and many others of various kinds.
They are obt.iinable in sheets of all sizes up to 15 by
12, and even larger, from the importers, Messrs. A. E.
.Stalcy and Co.

School of Art Wood-Ca.rvirvg.

Tin. School of .\rt Wood-Carvinj;. South Kensington, which
now occupies rooms on the top floor of the new buildiiif,' of
tlie Royal School of Art Needlework in Pxhibition Road, has
been reopened after the usual sunnncr vacation, and wc are
requested to state that some of the free studentships main-
tained by means of funds granted to the school by the London
County Council are vacant. The day classes of the school
are held from 10 to i and 2 to 5 on five days of the week, and
from 10 to I on Saturdays. The evening class meets on three
evenings a week and on Saturday alternoons. Forms of
application for the free studentships and any further parti-
culars relating to the school may be obtained from the
Manager.

264

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1Q04.

A School on tKe Ocean.

.\.MERICA.\ educational enterprise is responsible for the
scheme of a " Nautical Preparatory School " — in
other words, a school on board a ship that is con-
stantly afloat in the various maritime regions of the
world. A vessel of this kind, to effect its purpose, must,
of course, carry a professorial staff, whose members are
qualified to conduct the education of pupils, as well as
look after their moral and material welfare. But the
studies of sea-going scholars of this type, while akin
to those which form the curriculum pursued within
the four walls of a high-grade establishment on shore,
are supplemented by the novel opportunities and ever-
changing environment of a cruising vessel.

The Young America, the craft on which this bold
experiment in educational methods is to be carried out,
is a newly-built full-rigged sailing ship, the keel of
which was laid at Newport, Rhode Island, in the
summer of 1902. She has a displacement of about
3,000 tons, and length of 262 feet, and is claimed to be
of the most modern type of marine architecture. Elec-
trically lighted throughout, the vessel is provided with
all the requisites of up-to-date sanitary and hvgienic
science, and also those which meet the peculiar needs
of a wayfaring ocean school. Two steam launches are
borne, and ten rowing and sailing boats of navy
pattern.

The T Cling America sailed from Newport on her first
voyage in September last, and it is of interest to note
that the maiden cruise of the ship is to this country,
Edinburgh having been selected as the first city or
port of call, and London as the second.

Our visitor carries upwards of 250 American lads, de-
nominated " cadet pupils," and, as at present
arranged, a complete student course for these occupies
four years, during each of which an itinerary of
cruises is performed to various parts of the world. It
is not, however, obligatory to enrol, for the whole
period. In the first year, 16, coo miles will be
traversed. From Edinburgh and London the ship
proceeds to Christiania, Copenhagen, Gibraltar, the
Mediterranean, the ports of the West Indies, and
thence home to the United States, when a vacation
of four months ensues. During the second vear,
Lisbon, Venice, Constantinople, and Santiago com-
prise a few of the ports of call of the cruise. The
third year the ship visits St. Helena, Cape Town,
Bombay, Calcutta, Hong Kong, Yokohama, and San
Francisco. In the fourth and last year, Hawaii,
Sydney, Hobart Town, \'alparaiso, Rio de Janeiro,
-St. Thomas, and Charleston are among the ports of
call. \'acations follow each ended cruise.

At first sight it would seem that here a training-
ship is the central idea of the plan. But the school
on the Toting America, it is requisite to state, is not
primarily designed to train boys for sea service,
though, doubtless, in the nature of things its associa-
tions and influence will in many cases assist what may
be the embryo stages of naval careers of the future.
Strictly speaking, it is a school on a ship, and not, in
the more limited sense, a school-ship. The cadets take
no part in the working of the vessel, except for pur-
poses that accompany the routine of discipline, drill,
gymnastic exercise, and the ability to hand, reef, and
steer. From the last-named operations there is no
escape.

Notwithstanding that the actual work of the ship is

carried on independently of the cadets, the organisa-
tion is planned on naval lines. The Young America is
commanded by an experienced officer detailed under
the provisions of the United States Navigation Laws,
and the disciplinary standpoint is similar to that of the
world-renowned United States Naval Academy. The
cadets are formed into companies, and the companies
into sections, the respective ranks in the latter being :
cadet officers, cadet lieutenants, midshipmen, and pro-
bationers. Boys in the highest grade act as officers of
the watch, performing duties identical with those of
the ship's officers of like rank, only, however (so it is
said), for purposes of physical development, amuse-
ment, or as a reward of merit, the duties themselves
being carried on outside school hours.

A service as well as a dress uniform is worn, while
other articles of clothing conform to the standard
patterns. Such, in brief, is the naval aspect of the
ship's management ; the rest is an affair of the teach-
ing faculty.

A body of 1^ professors conduct what are called
collegiate and commercial courses. The former com-
prises an educational training for cadets who sub-
sequently intend entering American colleges, the L'.S.
Naval or the L'.S. Military Academy, or to secure a
liberal education independently of attendance at any
higher institution. The plan of the latter course is
laid on broad lines, the object of which is to impart a
sound general education, coupled with a practical
knowledge of the world's commerce, derived as much
as possible from personal observation in widely differ-
ing countries. In both sections the teaching of
modern languages is a feature ; those that may be
taken up are : French, German, Spanish, and Italian.
Certain of the cadets are instructed in theoretical
navigation, and steam and electrical engineering.
Considerable attention is to be given to various
branches of science — indeed, in some respects, the
Young America modestly subserves the functions of a
scientific and exploring expedition. Under the fostering
eye of a competent Director of Science, Prof. Porter E.
Sargent, deep-sea dredging will, with suitable equip-
ment, be pursued, and the treasures and wonders of
the tow-net set forth and explained. Then it is hoped
that the visits on shore during the ship's "globe-
trotting " will afford ample facilities for judicious
scientific collecting.

It is not to be expected that the gates of the world
will fly open to these cadet pupils ; and we may hope
that they will not broaden into sea prigs. Still, it
cannot be doubted that the world-wide travel that is
forecasted, in alliance with scholastic training, will be
of high advantage if properly assimilated and adjusted
to the needs of after-life requirements. It is a grand
tour of the seas, and round-the-world itinerary of
cities and sights of peculiar significance. .A broad
hint has been given that America's foreign trade
should ultimately receive stimulus, and new outlets
crop up for the development of her industrial and
scientific manufactures by the educational method in
question. If that be so, surely no one will grumble at
the means adopted to supply the fair promise.

The management of the Young America is vested in
a company, of which Lieut. -Commander C. H. Harlow,
an officer in the L'nited States Navy, is president, and
associated with him are several prominent naval and
industrial authorities.

It should be added that pupils are enrolled on the
roster of the school between the ages of 14 and 19
years inclusive. Bon voyage.

Nov., 1904.

KNOWLEDGE & SCIENTIFIC NEWS.

265

Sunspot VaLrioLtion irv
LoLtitvide.

By Wiii.iAM J. S. LocKVEK, M.A., I'h.I).
From a study of the facts regarding the dislrilnition
in latitude of spots on the surface of the sun, Mr.
Maunder and I e\idently hold different opinions, and 1
do not think that a further discussion ol the subject
will tend either to change them or ad\ance our know-
ledge of this spot distribution.

Perhaps I may, however, be permitted to make a
final reply to some of Mr. Maunder's remarks in your
October issue.

-Speaking of the term "spot-activity track," Mr.
.M.iunder says: " It is abinidantiy clear that he did
intend to intimate by it that the sjjots were gathered
together in certain districts or regions, separated from
each other by broad, barren intervals, and that these
districts, rich in spots, moved continuously dow invar_ds
towards the cc|u;itor." (Ihe italics are mine.)

I am afraid Mr. Maunder cannot have re.id my
paper thoroughly, or even carefully looked at the
figure on page 144.

In the paper I have staled (p. 145), " in tiiis way it
was possible to trace the varying positions, as regards
changes of latitude, of the centres of action or maxima
points of the curves, from year to year . . ."

And on page 147 the term " spot-acti\ ity tracks " is
applied " simply to the changes of positions of the
regions in which they (the spots) are most numerous."

I have nowhere mentioned that these regions were
separated from each other by " broad, barren inter-
vals," as he calls them, for such a statement would be
against all the facts ; if the text and diagrams be con-
sulted, no such general deduction can possibly be made
with accuracy.

It w-as to make this, among other points, clear, that
Fig. I, p. 181, in the .August number of this journal
was inserted, where it will be seen that the portions of
the curves between the individual maxima do not reach
down to the zero line, which they should do if those
regions were "broad, barren intervals." If Mr.
Maunder considers that these " broad, barren inter-
vals " are suggested on the curves marked .'\ in plates
4 and 5 of my paper, then this is another indication
that he has not read it carefully before criticising it.
In describing these curves to which reference has just
been made, I pointed out (p. 146) that they " were
proportionally thickened to indicate approximately the
relative amount of spotted area at these centres of action,
or, in other words, the heights of the maxima points
on the vearly curves. These curves thus indicate for
each year the positions, as regards latitude, of the
particular zones in which the centres of spot-activity
occur. "

Mr. Maunder in his letter states further that he
" explained therein the nature of the mistake which
Dr. Lockyer had made with regard to the maxima on
which he based his paper, and that his method of jf)in-
ing them up so as t') show apparent lines of drift was
not only purely arbitrary, but was often against very
distinct and positive evidence."

I am afraid, however, I cannot accept this explana-
tion which he has so gratuitously offered. To my mind
the larger the sunspot or its greater extent in latitude,
and the longer it exists, the more important becomes
the region in which such a disturbance takes place.
Mr. Maunder evidentiv thinks otherwise.

Ill the imtc uu |).ii;c i ^^) of this journal, which fi'om
its general tone I assume Mr. Maunder wrote, it is
stated th.'it " Mr. Maimder showed that the (Greenwich
Simspot Results for the last 30 years fully confirmed
Spoier's Law," yet Mr. Mainuler now claims priority
for a statement I have made which is not in strict
accord with this law.

.'\ccording to Sporer's Law, formulated about iSHo,
the highest spot latitudes occur about the time of sun-
sjiot minimum. In my paper I suggested that this l.iw
needed modification bec.iuse an analysis of the facts
indicated that : —

[a). Outbursts of spots in high latitudes are not
restricted simply to the epochs at or riboul a
sunspot minimum, but occur even up to the
time of sunspot maximum.
(/'). The spots tended to reach their highest lati-
tudes at or about sunspot maximum,
[c). From sunspot maximiun until about the
following minimum high latitude spots were
for the most i)art consi)icuous by their
absence.

The ;ibo\e three deductions, all ol which can he
gathered from an intelligent exnmin;ilion of the plates
accompanying niv paper, show that the appearance of
spots in high latitudes he.irs a f.iirlv definite relation
to the simspot maxim;i and minima epochs.

Mr. Maunder refers to a p.-iper (Monthly t\'ol. May,
1903) prepared by him by the desire of the Astronomer
Royal, in which his deduction as regards the occiuTenci-
of high latitude spots is as follows : —

" Taking them as a class by themselves, they were
seen irregul.irly, appearing at times which did not
seem to bear .any fixed relation to any one of the four
chief stages of the sunspot cycle — minimum, increase,
maximum, and decline. . . ."

.Since Mr. Maunder's "brief preliminary text," to
which he refers, suggests an irregularity of appearance
of high latitude spots, and my statement restricts this
time of appearance from about a sunspot minimum to
about a sunspot maximum at which the highest lati-
tudes are attained, I fail to see how he can " claim "
the priority of the deduction I made.

Mr. Maunder has further forgotten to mention one
of the conclusions, corrobor.-iting my statement, to
which F'ather Cortie recently arrived, namely : —

" Cireater disturbances are most prevalent in high
Latitudes at or near the times of solar maximum . ."
(Monthly Not., Vol. 64, p. 76O.)

Would not Father Cortie also ha\e referred to Mr.
Maunder's " brief preliminary text " if a statement
equivalent to the abo\e had been pre\iously published
by Mr. NLaunder?

In conclusion I may be permitted to add that it was
very far from my thoughts to take the " results " of
.Mr. Maimdcr's paper as he states in his last letter.
Researches at the .Solar Physics Observatory rendered
it necessary to make a detailed study of simspot ob-
servations, and use was made, bv permission of the
.Astronomer Royal, of data (which at the request
of the .Solar Physics Observatory had been brought
up to date) and not of results derived by Mr.
Maunder.

It seems necessary to point out to Mr. Maunder that
observations are made, collected, and reduced at public
expense, in order that they may be studied by those
who wish to utilise them for the purposes of science,
and are not the " property "of any computer or assist-
ant who inay have been charged with the duty of pre-
paring them for publication.

266

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

ASTRONOMICAL.

The Nebulae and the Milky Way.

It is oRen stated that the iiel)ul;e piopniy bn called — the
"white" nebulie — avoid the galactic region and cluster
towards its two poles. It is manifestly so with respect to the
north pole of the Galaxy, but Dr. C. Easton, in the Astroiio-
iiiisclu' Sdihyiihtcn (No. J969I. questions if the same relation
holds good for the southern pole. The statistics at our
disposal do not bear it out, but this has hitherto been generally
explained as due to the insufficiency of obser\ations in the
southern hemisphere. Dr. Easton shows that this is not the
case ; for since the Galaxy is inclined at an angle of 6o- to
the equator a considerable part of the galactic northern
hemisphere lies to the south ot the equator, and of its southern
hemisphere to the north. Calling the former segment A, the
latter B, we ha\e

Faint nebuhe
Bright nebuUe

A 754 a 1043
A 152 B 71

If nebulas were really distributed on the whole in the same
way in the two galactic hemispheres, and if an}- apparent want
of the expected condensation round the south galactic pole
were simply due to the insufficiency of observations in the
southern hemisphere, then more nebula;, both bright and
faint, should be observed in segment B than in segment A.
There is an increase in faint nebuUe, but a most striking
falling off in l>riglit. This indicates a great increase in the
proportion of faint to bright nebuke in the galactic southern
hemisphere, and it is exceedingly improbable that future
observations in the southern hemisphere will discover so large
a number of nebuUe round the south galactic pole as to bring
it into symmetry with the northern. The distribution in the
tw o hemispheres appears to be different, and Cleveland .Abbe's
theory of an •' ellipsoid of nebulas" with its major axis at right
angles to the galactic plane, seems to accord with this want of
symmetry. Dr. Easton, in the concluding portions of his
paper, regards the faint nebulosities as allied to the stellar
agglomerations of the Milky Way ; the nebuke properly so-
called to the sparsely distributed stars of the general stellar
system, the non-galactic stars.

* * *

Explanation of the Martian a^nd L\ina.r
Canals.

Professor W. H. Pickering, in Popuhir A^trvnninw dccWnas
to follow- Mr. P. Lowell in his heroic scheme of artificial
pumping to account for the flow of water in the Martian
canals. He shows that the lunar canals are dotted by small
craterlets, and are so symmetrically connected with them as
to show a causal connection. Pie therefore suggests that the
canals on the Moon, and by analogy on Mars also, are lines of
volcanic action where the crust has been fractured, and that
enough water and carbonic acid may escape from the centre
craterlet and fiow dow-n its sides to de\'elop the vegetation
upon its slopes, whilst the smaller quantities escaping from
various points along the radiating cracks similarly de\-elop the
vegetation along their course, the " lakes " and " canals " as we
see them being thus regions of vegetation. On account of the
rarity of the atmosphere, the vapours, instead of rising, would
immediately spread themselves along the surface of the ground.

The Monthly Rcvici^ for October contains an article on
"The Markings on Mars: a Plea for Moderate Views," by
Major P. B. Molesworth, R.E. Pew astronomers can speak
on the subject of Mars with the authority of .Major Molesworth,
since his studies of the planet ha\e been carried on under
exceptionally good observing conditions, with the utmost per-
severance, and with great skill in delineation. He concludes

that : (i) The markings on the surface of the planet are more
or less permanent, ^but subject to minor changes. (2) Their
intensity depends in some way on the Martian seasons.
(j) The structureof the delicate detail is the same all over
tne planet, both in the light and dark areas, the only difference
being in the varying tone of the " background." (4) This
detail is " the integration of markings far too small to be
separately defined."

* * *

The Ninth Satellite of Saturrv.

'I he first visual observation of this object was obtained on
August S by Professor 1*^. K. Barnard at 18 hrs. o min. G.M.T.
Itsappareut place was K.A. 21 hrs. 23 min. i-osecs. ; declination,
lO ' 36' S". On September 3 Professor Barnard found no star
was visible in this place. The magnitude of the object was
estimated at i5'5 or i6-o. Another observation by Professor
Barnard is dated September 12, when the magnitude of the
satelhte was given as 16-7.

In the number of the Ubscrvatoiy for October, Mr. Cromiuelin
gives the result of a rough preliminary examination of the
orbit from the very few observations which have yet been
published. He finds that the hypothesis of retrograde motion
suits the observations as given much better than that of direct
motion. This, if established, would be a most extraordinary
circumstance, the other eight satellites moving directly. Mr.
Crommelin gives the siderial period as 443 days, and the
distance 6,gOo,ooo miles, inclination to ecliptic about 6°, to
Satyrn's orbit about 4j '. to Saturn's equator, 30 ". The magni-
tude given by Professor Barnard, i6-7, would correspond to a
diameter of about 120 miles.

* * *

Radiation in the Solar System.

In the course of an address given to the British .Association,
Professor J. H. Poynting gave in clear and succinct form some
of the conclusions which may be drawn from researches in
recent years, both on the temperature effects of radiation and
the effects due to light pressure. Beginning with Stefan's
law, that the stream of energy is proportional to the fourth
power of the temperature, reckoned from the absolute ^ero
273 ' below freezing point on the Centigrade scale, he quoted,
as probably not far from the true value, that the stream of
radiation from the sun falling perpendicularly on i sq. cm.
outiidi: the earth's atmosphere would heat i gramme of water
5*f" C. every second, or would give ^f caloric per second.
Hence he deduced that the mean temperature of the sun's
radiating surface is 6000 ', if the sun radiates as a body would
do which is perfectly black when cool. Further, he gave a
table of temperatures at various planetary distances from the
sun's centre : —

Distance from the Temperature

Sun's centre. Centigrade.

At Mercury's distance. . . . 210° Tin nearly melts.

At V'enus's distance 85° .Alcohol boils.

At Earth's distance 27^ Warm summer day.

At Mars distance — 30 Arctic cold.

At Neptune's distance .. —219' Nitrogen frozen.

Now, the estimated mean temperature of the earth's surface
is about 16° C, which is sufficiently ne.ar the value given in the
table when the radiation from the surface of the atmosphere
and other such conditions are taken into account. Professor
Poynting then points the moral that, given atmospheric con-
ditions on Mars not very unlike those on the earth (as obser-
vation seems to show), even the highest equatorial
Martian temperature cannot be much greater than —38", and
•' it is hard to believe that he can have polar caps of frozen
water melting to liquid in his summer and filling rivers or
canals. Unless he is very different from the earth, his w-hole
surface is below the freezing point."

Turning, then, to the effects of light pressure, he gives the
total eftect on the earth at its present distance from sunlight
as 70,000 tons. Since gravitation depends only on the mass
and light pressure on the surface area, it follows that were
the earth's volume divided up into separate spheres, each
irrJoo cm. in diameter, the pressure of light would balance
the pull of gravitation. If, on the other hand, we diminish the
radiating body whilst retaining its high temperature, we find
similar effects. If it were possible to reduce the sun to a dia-

Nov., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

267

meter of 20 miles, whilst keeping its temperature of Oooo'', a
balance between the pull of gravitation and the push of sun-
light would again be held even. If, in addition, we diminish
the temperature. Professor Poynting showed that two spheres,
each of the density and temperature of the earth, would
neither attract nor repel each other when their diameters were
about 6'S cm:, if they received no appricial>le radiation from
the surrounding region. This last result is of importance in
relation to the meteoritic theory. Seven centimetres is a
large value for the average size of meteorites in a swarm, yet
Professor Poynting"s research seems to intiicatc th.it the ten-
dency of the members of a swarm smaller than these would be
to repel each other and scatter, not to attract each other,
collide and ignite.

BOTANICAL.

Hj S. A. Skan.

Professor .V.NESTi.KK.whose investigations into the poisonous
properties of Vrimula ohcoiiica were the subject of a note in
'• KsowLKDGF. " about three years ago, has now published, in
the form of a brochure of 46 pages .ind four plates. ,a more
comprehensive account of his experiments with various species
of the genus, undertaken to ascertain which of them are
capable of produiiug skin-irritation, and the origin, properties,
and efiects of the poison. Injury is cau.sed most conmionly
by Primula olicoiiuu, to which species the paper is chiefly
devoted; but Professor Nestler has clearly proved that other
species are also poisonous, though less virulent. The well-
known Chinese primrose (/'. siiunsis). P. Su-I'iddii, and /'.
cortiisoiiits, all three of which belong to I'ax's section Sinenses.
in common with P. ohcoiiitn, have been tested and proved
poisonous. Eleven other species, including P. i>JJuiiutlis, P.
Jariiwsa, and the .\uricula (/'. Auricula), were also tested, and
were found to be innocuous. The author shows tliat the irri-
tation of the skin is caused by the yellowish secretion of the
glandular hairs which clothe the underside of the leaves aud
the flower-stalks. This secretion contains largo numbers of
variously-shaped, often needle-like, crystals, and its effects on
the skin appear to be identical with those of menthol.
» * ■»

The Welsh poppy (Mecano/'sis ciimhricii), which is found wild
in Wales and some of the western counties of England, is
probably the only species of the genus known to many of the
readers of " KNt)wi,Er)c;E." There are, however, several
others, some of which, such as M. iiepulcnais, M. W'alliLhii, and
M. lu-tcropliylla, may be met with in English gardens. .Mto-
gether about 20 species are known, and they mostly inhabit
the high-level regions of Northern Indi.i, Western China, and
Tibet. The interesting circumstances attending the introduc-
tion of another species to cultivation are recorded in a recent
number of the ■' Ciardeners' Chronicle." This species, M. in-
tefirifoha, has for a long time been represented in herbaria,
and attracted the attention of Messrs. Veitch, of Chelsea, who
dispatched a collector to the Eastern Tibetan frontier with
the main object of procuring some seeds. The plant was found
growing in great profusion at elevations from 11.000 to 15,500
feet, and was only reached after an arduous journey, during
which the travellers suffered more or less from the r.ircfied
atmosphere, from the cold, and from snow-blindness. Its
seeds were secured and sent to England, and now its large
yellow flowers, which in the wild specimens are sometimes 8 to
10 inches in diameter, have for the first time appeared in our
gardens.

* * *

.A Bath firm of engineers has recently met with some vege-
table matter in the water of the famous King's Bath, of which
the temperature is about 120° F. It was found in a shaft
through which the water from the hot spring rises and over-
flows to fill the bath, and proves to be a filamentous Alga
known as Uscilhiria tlu-nniilis. Mr. G. S. W'est has an interest-
ing paper in the " Journal of Botany," 1902, in which he gives
an enumeration of species of .-Vlga; found in a collection made
in the hot springs ot Iceland, with the addition of a few from

the Malay Peninsula. In Iceland the highest temperature of
the water in which pl.ints were collected was 185' h". The
late Professor W. H. Brewer, in a note published in the
" .\merican Journal of .Science," 1.S66, \LI.. records (hi- pre-
sence of living .Mgie in the geysers of Plutou Creek, California.
In this case the highest temperature of the water found to
contain living plants was about 200^ F.

OR.NITHOLOG1CAL.

l]y W. P. I'VCK.VFT.

Red-baLcked Shrike Breeding in
Confinement.

Di;. A. r.. GiiNTHi-.i;, h'.K.S., is to be congr.itiilated 011 ha\ iiig
succeeded in breeding the Red backed Shrike /.kh/ks cullurin,
in confinement. In the Avicnltural MiiL^a:.inc for Octoljcrhe
gives a long and delightful description of the habits of his
birds botli before .'ind during this momentous time.

Taken from the nest last year, aud reared by h.uid, they
were turned out early this year into a large .iviary. affording
plenty of cover in the shape of large bushes. Towards the
end of May, Dr. Giiuther first made the discovery that nesting
operations were going on by finding a nest in a holly-bush
4 feet from tlie ground, aud containing five eggs. This nest,
be it noted, though built by l)ircls which had never known
freedom, was in all respects typical of the s|)ccies.

On June (1, after 14 days' incubation, hve yoimg appeared —
nearly a month earlier than would be the case with wild birds.
Unfortunately, cold weather soon set in, and this proved fatal
to the callow young, which died on June 14.

The bereaved birds, however, soon began to pair ag.iin.
By June 24 the female was silting on the old nest; on .another
ilutch of five eggs, which, curiously enough, were mure bril-
liantly coloured th.an those of the first clutch. ()n July 7 four
of the eggs had h.itchcd out, the fifth ne.\t day. This last
nestling was conspicuously smaller than the rest, aud died
next day ; another death occurred on the iith. ISy the 2 jrd
two of the three remaining young h,id left the nest: the third
followed next day. But they h.id esidently started too soon,
as the flight feathers were not big enough, aud they had to
spend the next three days on the ground before they could
get back into the bush again.

By August 2S the parents had ceased to feed them, aud they
are still flourishing.

* » *

Birds of Paradise in England.

No less than five Birds of P.ir.uiise arc now living in the
aviaries of Mrs. Johnstone, a prominent member of the .-Xvi-
cultural Society. Three species are represented two King-
birds of Paradise, Citcinui-us rci^ius, to be transferred immediate-
ly, we are happy to say, to the Ciardens of the Zoological
Society, two Lesser birds of Birds of Paradise, Piirndisid minor,
and one (ireat Bird of Paradise, I'lnadi^ia tiputhi, and all
are in excellent condition.

Never before, probably, has Ciuinurus rigiiis been seen alive
in ICurope. It is therefore to be hoped that they will live
long, more especially as they are regarded by many as the
most beautiful species of their kind.

* * »

Immigration of Great Snipe.

During the; end ol Sipleniber these: isl.nids appear to have
been visited by consider,if)le numbers of the (ireat or Solitary
Snipe (Oatliudf^o ninjnr), inasmuch as individual specimens are
recorded as having been shot in Shetland on September 20, in
Caithness aud Dumfriesshire on September 2(S, and in Coventry
on October i.

Though occurring regularly every year in Ivngland, it is
regarded as a rare autumnal visitant both in Scotland and
Ireland.

The Great Snipe is peculiar in haimling much driei' places
than the Common Snipe.

j68

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

Osprey in Surrey.

During the middle of September oue of these magnificent
birds took up a temporary residence near the lake at Cran-
U'igh. and, as might have been expected, was shot almost
immediately — charged with depredations on rainbow trout
which have been introduced there. Since then another of
these birds has been seen, and an appeal has been made by
Mr. John Bickerdyke, in the columns of the FiilJ for ( )ctober i,
fur its protection.

* * *

Aquatic Warbler in Norfolk.

The l-'iclii (October S) records the capture on September 15
at Cley, in Norfolk, of an a<iuatic warbler, Acroiiphuliis aquati-
nts. This is the seventh occurrence of this bird in Great
Britain. The sex of this last specimen is not stated.

* * *

White Waterhen.

The Natural History Museum at South Kensington has just
received a very beautiful variation of the Common Waterhen.
The bird, which was killed at Stour, Dorset, on October 2, is
very nearly entirely white, the red colour of the frontal shield,
and the green colour of the legs, forming ;i very handsome
contrast with the snowy plumage. The red colour of the beak
and the " garter " round the leg, it is interesting to notice,
was very intense, but the green pigmentation of the legs and
toes was paler than normal; the claws, indeed, were nearly
white.

ZOOLOGICAL.

IJy K. LVUEKKKR.

The Mammals of Central Asia.

Ik connection with the article in our September number,
on the mammals of Tibet, considerable interest attaches to
Dr. W. Leche's account of the large m.immals collected by
Sven Hedin during his travels in Central Asia between i^Sgy
and 1902, published at Stockholm, in the sixth volume of tfie
" Scientific Results " of that adventurous journey. Perhaps
the most interesting conclusion is that the wild camels found
in large droves in the deserts of Central Asia are truly wild
.animals, and not, as has been generally supposed, the descend-
ants of individuals escaped from captivity. From the exist-
ence of intermediate forms, the author is led to confirm the
view of the present writer that the Tibetan argali is merely a
local race of the Siberian animal, and that if should conse-
([uently be known as Ovh ammun hodf^soni. He also describes
a stag which appears to be in some respects intermediate
between the Yarkand (Ccrvus cauadensis) and the Lhasa stag
(C. alhirostiis) ; and arrives at the conclusion that the two
forms of bear mentioned in our article belong to a single
species (Ursm pnmwsus).

* * *

Armoured Cat-Fishes.

.Vn important memoir, by Mr. C. T. Regan, of the British
Museum, on a peculiar group of South American freshwater
fishes, which may be popularly known as armoured cat-
fishes, has recently been published in the 'J'raiisiuiioHs of the
Zoological Society. For a long time these fishes were in-
cluded among the SHurida-, or true cat-fishes, as typified by
the wels (Si7»ri(s ,i,'/i(;i(.s) of the rivers of Continental Europe,
but are now regarded as forming ;i family (Lvrkariida:) by
themselves. The majority of the characters by which these
fishes can be distinguished from the Silundic are connected
with the skull and skeleton, but the more typical forms may
be easily recognised by the armour of overlapping bony plates
protecting the body, from which the type genus Loricaria takes
its name; the inferiorly-placed sucking mouth is also very
characteristic. There are, however, certain degenerate types,
such as .1 ixv.s, in which the armour has been completely
lost. Probably these fishes are derived from the Siluridic,
and their recognition of their right to rank as a family adds
one more peculiar type to the fauna of Central and
South .'\merica, which their ancestors m;iy have reached by
means of a former land-coimeetion with Africa, and where
they range from Panama and Trinidad or Porto Rico to
Uruguay. No less than i8g species, arr.inged in 17 genuine

groups, are recognised. It appears that these fishes are in the
habit of anchoring themselves to stones in the river-bed by
means of the sucker-like mouth ; respiration being at such
times effected by taking in water through the gill-openings
and expelling it again by the same aperture in the opposite
direction. Most of the genera are represented in all the
South American river-systems, while even some'of the .species
have a very wide geographical distribution.
-If -X- *

" The Pa.ca-rana.."

In this coluuui reference has previously been made to Dr.
("loeldi's interesting re-discovery of the remarkable Peruvian
rodent Dinoiitys braniclii, hitherto known only by a single indi-
vidual captured in 1873. As Dr. Goeldi's paper is now pub-
lished in the October issue of the Zoological Society's I'ruccid-
iiii;s, a few notes may be added on such an interesting creature.
In the first place, it appears that the animal is known to the
Tupi Indians, by whom it is called the paca-rana, or false paca,
in allusion to the resemblance of its coloration to that of the
true paca {Curln.i^tiiys pam), from which it differs, however, by
its well-developed tail and the absence of cheek-pouches.
The Tupi name mav be adopted as the popular title of the
species. Dr. Goeldi states that the paca-rana is a rodent of
phlegmatic and gentle disposition, which may account perhaps
for its rarity, if, indeed, it be really scarce in its nati\'e home,
which is probably the eastern slopes and table-lands of the
Bolivian and Peruvian foot-hills bordering on Brazil, inclusi\e
of the headwaters of the Purus, Acre, and Jurua rivers. Dr.
Goeldi adds that ho " shall soon have occasion to show that a
scientific exploration of that region will result in a multitude of
great surprises both from a zoological and a pakeontologic.al
point of view, of which the interesting re-discovery oiDinoinijs
hranicln is only a first instalment."

* * *

The Races of Europe.

In his Huxley Memorial Lecture, delivered on October 7,
Dr. Deniker, after referring to Huxley's recognition of two
main stocks, the fair Caucasians, or Xanthochroi, and the dark
Caucasians, or Melanochroi, in Europe and Asia, expressed
the opinion that there are really six well-marked European
races of mankind. These are (i) the blonde, wavy-haired,
long-headed, long-faced, and tall Northern Race ; (2) the
Eastern Race, which is also blonde, but has straight hair, a
rather short head, and broad face, with a short stature ; (3) the
Ibero-insular Race, of Spain and Portugal, which is dark, very
short, long-headed, with straight or retrousse nose, and some-
times curly hair : (4) the Western Race, dark, round-headed,
and short, with round face, broad nose, and thick-set body ;
(5) the .Mlanto- Mediterranean Coast Race, very dark, mode-
rately long-headed, and fairly tall ; and (6) the Adriatic Race,
from the borders of the Gulf of Venice, which is dark and
short-headed, with the nose slender and straight or arched.

# * *

The New Central African Pig.

When Stanley heard of the occurrence in the forest of
Central .\frica of the animal now known as the okapi, he also
saw or received reports of a large species of pig.
These reports have proved true, for Mr. R. Meinertz-
hagen has killed specimens of a wild swine from the eastern
side of the great forest, the spoils of which have s ifely reached
the Natural History Museum. Mr. O. Thomas reports that
these indicate not only a new species, but likewise a new
generic type of wild swine, for which he suggests the name
Hylu(h(i-nis ))hiiieytzha,t;cin. The forest hog, as it may be
called, apparently comes nearest to the wart-hogs (Phaco-
clia-nis) of .Africa, but has a less specialised type of skull and
dentition, and thus serves to connect those hideous creatures
with more typical swine. The tusks, although very much
smaller, have the characteristic curvature of those of the wart-
hog, and there is the same reduction in the number of the
upper incisors to a single pair. The coat of black hair is, how-
ever, much more profuse than in the wart-hogs. Although the
discovery of this new type falls far short of that of the okapi in
the matter of interest, yet it is nevertheless one of very con-
siderable zoological importance. Unfortun.ately, the specim.ens
sent home are too imperfect for mounting. Mr. Thomas's
description of the new animal appeared in Natiitx of
October 13.

Nov., 1904.]

KNOWLEDGE .<c SCIENTIFIC NEWS.

269

An Electric Influence
Experiment.

Interesting Illustration of the Prin =
ciple of the Wimshurst Machine.

Bv Chakles E. Ben ham.

The following simple experiments will bo found ontortainin.!,'
in themselves, and at the same time they will help to elucidate
the principle of the remarkable accumulation of electricity
which occurs in the well-known Wimshurst intluonce machine.

Take four pieces of s; hiss — half-plate negative glass (6' by 4|)
will do very well — and mount a 3-inch circle of tinfoil on each,
a little above the centre, as shown in fig. i. Coat the glass
well on both sides with shellac varnish, which, by the way,
should always be filtered through a few thicknesses of fine
muslin to ensure a good smooth surface.

Fix two of the glass plates, which we will call .\ and B, edge
to edge horizontally, with the tinfoil downwards, holding them
in a \ice. or pushing their ends into a grooved block of wood
as shown in fig. 2.

Lay the two other plates, C and D, with tinfoil upwards, on
the fi.xed plates, C on A and D on B. The tinfoil not being
central, the glass will project beyond the edge of A and H,
thus enabling C and U to be handled and moved as required
in the experiment.

Touch C and D with the finger and they will receive from A
and B respectively an infinitesimal charge of electricity, prob-
ably quite imperceptible, even with a delicate electroscope.
Remove the finger, and then without displacing C turn I) over
on to it, so that the two tinfoils of the upper plates are in con-
tact. The surface of C D will now have the combined charges
of C and D. Touch A, and it will receive by induction a
charge equivalent to this combined charge — still an impercep-
tible one. Lay the pair on B and touch B, which will likewise
receive a similar double charge. Open out the two plates and
repeat the whole process. It will be seen on consideration
that the second time C and D will receive practically double
the charge they first took up. At the third operation they will
again double their last charge, and so on. It is not really
quite double, but taking the accumulation as being practically
in that ratio, it means that in ten operations the original charge
will have increased more than a thousand times. At any
rate, before the tenth time sparks will probably be observed
at each touching of the tinfoils, and will be found to increase
every time until the limit of the capacity of the surfaces is
reached.

To those who are familiar with the principle of the " doubler,"
invented by Bennet more than a hundred years ago. there is
nothing surprising about this method of producing electricity,
but to the tyro, or to persons unacquainted with electric
phenomena, this creation of a powerful and increasing series
of sparks without any manifest original source cannot fail to
seem astonishing.

It is evident that while electricity is produced by this simple
process — and with large plates is produced in considerable
quantities — it would be mechanically inconvenient to construct
an apparatus to go through these intricacies of touching and
transposing glass plates, but a further experiment will show
how the most troublesome part of the process may be dis-

pensed with, and will at the same time illustrate in a striking
manner the very principle of the accumulative power of the
Wimsliurst machine.

For this second experiment only three of tlie tinfoil discs
are required — A, C, and D — and it will be more convenient if
C and D are on one plate. A being fixed as before, lay the
larger plate upon it with the tinfoil C (uppermost) over A.
Charge C by touching as before. Then slide the upper plate
so that D is over A. and, by touching, charge that loo. C anil
I) now have between them double the charge of A, but of
course a charge of opposite sign. C and D cannot be brought
into contact as before, but if the plate is moved so that A is
midway between them (as in fig. j), A will be under the
inlluence of both, and will, when touched, receive a charge by
induction, and a repetition of the process will quickly result in
accumulation, so that all three discs will soon be strongly
charged. On separating them and touching each in turn,
strong sparks will be given off by each.

The application of this principle in the Wimshurst machine
is at once obvious, though it has never perhaps been illus-
trated in this way before. I'"ach sector of the Wimshurst, as
it passes under the brush, is earthed while under the influence
of more than one sector of the other di.sc, for it is within the
field of at least two or three of them. The sector, when
earthed by the brush, is, in fact, in the position of A in fig. j,
while the adjacent sectors of the other disc are etpiivalenl to
C .and D in the above experiment. Kach of the four brushes
of the neutralising rods places a sector at a similar .advantage
for increasing its ch.arge, and hence the ready .accunmlation of
the Wimshurst machine.

.•\fter this it also becomes evident why a certain number of
sectors are advisable for the Wimshurst machine. It will,
indeed, act without any sectors at all, but only while the
brushes are new .and very large, their ends that touch the glass
taking the place of the tinfoil. But in practice, the inventor
of the Wimshurst machine recommended th.it there should
never be less than a certain number nf sectors, the minimum
depending on the size of the plate. The reason for this
minimum would appear to be, in the light of the experiments
described above, that with widely separated sectors the
carriers would not be within the field of more than one at a
time, in which case the multiplication of the charge would not
take place. On the other hand, sectors can be too numerous.
This is not only because of the leakage involved, but also
because the carrier (represented by A in our experiment)
would then be under the inductive influence, not only of the
sectors of the other disc, but also of those to right and left of
it on its own disc, which sectors are charged with electricity of
sign similar to its own, and tend therefore to neutralise the
inductive effect of those on the other disc, which are of
opposite sign.

Gl\jttonous AnimoLls.

By R. LVDEKKER.

Maw kinds of carnivorous animals, such as the larger
members of the cat tribe, are in the habit of
periodically eating very heavy meals, and then abstain-
ing altogether from food for several days, until the
pangs of hunger once more reassert themselves.
Pythons and certain other snakes come under the
same category, as does also the common or medicinal
leech. Such animals clearly are not to be classed as
gluttonous — they might almost as well be included
among fasting animals — they merely take in large sup-
plies of food at long intervals, and, on the average, do
not appear to devour more than a normal amount of
nutriment. Vultures, on the other hand, although
they likewise require a period of abstention from food
of some length after each gorge, do appear to con-
sume very much more than an average quantity of
food, and, therefore, strictly speaking, come within
the scope of the present article.

270

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

The ;:■ I ;■ - I.. '^ :.:•_:: :;.,,;, ;;... ;: ■ ;,., ;,:.i_e 1^

intended are, ho\ve\er, such as are in the constant
habit of consuming abnormally large supplies of food
without taking intervals of unusual length between
their meals. Among wild animals such instances are
rare, but are more common among carnivorous than
among herbivorous or frugi\orous types. Indeed,
among purely herbivorous animals, there does not
seem to be a single species, either wild or tame, which
deserves to be called a glutton. It is true that sheep
and cattle, when suddenly turned into a field of green
wheat or other succulent herbage, will often eatsuch
a quantity as to be in danger of suffocation unless
operated upon with the trocar; Iiut in this case the
evil results are largely due to the nature of the fodder,
which, during the process of digestion, develops a
quantity of highly expansile gases, rather than to
absolute gluttony on the part of the animals them-
selves. \ot but what domestication has a tendencv
towards the development of greedy and gluttonous
habits, as witness the familiar cases of the pig and
the duck, the wild ancestors of which are among the
most active animals, and display no tendencv to over-
eat themselves.

Be the exact position in the present category of the
above-mentioned wild cre.itures what it mav, there can
be no doubt that, as indicated by the first of its popu-
lar names, the glutton, or wolverine (Gulo lusats) is
entitled to a very prominent position among greedy
animals. Xot but what, as is almost universallv the
case in analogous instances, the creature's propensi-
ties in this direction were considerablv exaggerated bv
the older writers. We may dismiss, for instance, as
pure fable the old story that when one of these
creatures had indulged in an extra big gorge it was
in the habit of squeezing itself between the" stems of
two fir trees growing close together in order to get
rid of its meal. Xevertheless, modern testimonv is to
the effect that the glutton thoroughly deserves its
name, and that its eating powers are well-nigh, if not
altogether, unequalled by its compeers in size. It is,
however, very ditlicult to find anything like accurate
data on this point, or, indeed, a statement as to the
weight of the creature. Here occasion mav be taken to
refer to the deficiencies of natural history works in re-
gard to the weight of animals. For instance, in three
well-known manuals of British mammals no mention is
made of the weight of the badger, which might serve
as a basis for an estimate of that of the glutton.
Roughly speaking, the latter weight may, however,
be estimated at between 35 and 45 pounds. Now as
regards the amount of meat a glutton has been known
to eat, the only definite statement within the writer's
knowledge is to the eflfect that one of these animals
consumed 13 pounds at a " sitting," or, at all events,
in a single day. .And since in a wild state the
creature's appetite would probablv be sharper, it can
scarcely be an exaggeration to sav that a glutton can
eat abf>ut a third of its own wei^Iit in a day. If is true
that this is nothing like the proportion of food to
weight that has been recorded in certain smaller
creatures to be noticed later on, but then small animals
have very frequently much greater functional acti\ itv
than larger ones, as witness the muscul.ir power of an
ant or a grasshopper compared to that of man.
Nevertheless, 13 pounds of solid meat is a good record
for a creature of the size of a glutton, which is about
half as big again as a badger.

Not only is its appetite wondcrfullv good, but the
glutton displays extraordinary acuteness and

perseverance in getting at stores of concealed food ;
somewhat tainted carcases forming its favourite boiine-
hcitche. In the forest districts of Arctic North America,
which, in common with similar latitudes in the old
world, form the home of the glutton, the hunters are
in the habit of concealing the carcases of their quarry
in caches for future use ; and from such depositaries it
is almost impossible to keep out the wolverine, which
has been known to gnaw through a solid log of timber
in order to obtain access to the daintv. When access
is gained, the creature will gorge itself to satiety, and,
what is more, will shortly after return for another and
yet another meal, until the supply is finished ; for the
glutton, unlike the larger cats, does not apparently
stand in need of a protracted fast after a carouse, but
has scarcely finished one meal when it is ready for
another.

Most of my readers, it may be presumed, are
acquainted with the wolverine at least by its fur, which
is now largely used for carriage-rugs, samples of
which may be seen in the furriers' shops, where a
stuffed specimen of the entire animal is also some-
times exhibited. Indeed, the specimen now exhibited
in the Natural Hislory Museum was bought ready
stuffed from Messrs. Shoolbred. Somev.hat badger-
like in general appearance, but with a bushy tail of
medium size, the wolverine has beautiful long silky
hair of blackish brown colour relieved by a broad
ellipse of golden tawny.

Our next example of gluttony is afforded by a fruit-
eating bat, one of the group commonly known as
flying-foxes ; the species in question being a native of
India and the Indo-Malay countries as far eastward
as the Philippines, and technically known as Cynnpterus
marg.naius. From its gluttonous habits, this bat is a
great scourge to fruit-growers in the East ; the extent
of its eating powers may be gathered from the follow-
ing anecdote recorded by the late Dr. G. E. Dobson,
in his time the great authority on bats of all kinds : —

" To a specimen of this bat obtained by me at
Calcutta, uninjured," writes this author, " I gave a
ripe banana, which, with the skin removed, weighed
exactly two ounces. The animal immediately, as if
famished with hunger, fell upon the fruit, seizing it
between the thumbs and the index fingers, and took
large mouthfuls out of it, opening the mouth to its
fullest extent with extreme voracity. In the space of
three hours the whole fruit was consumed. Next
morning the bat was killed, and found to weigh one
ounce, half the weight of the food eaten in three hours.
Indeed, the animal, when eating, seemed to be a kind
of living mill, the food passing from it almost as fast
as devoured, and apparently unaltered, eating being
performed alone for the sake of the pleasure of eating.
This v.ill give some idea of the amount of destruction
these bats are capable of producing among ripe fruits."

K close race with this bat in respect to the amount
of food devoured is run by th° common mole, which
is one of the most greedy of all mammals, and will, it
is said, perish of hunger and exhaustion if kept with-
out food for a few hours. Indeed, when we remember
that the mole feeds exclusively on animal substances,
which are much more highly nutritive than those of a
vegetable nature, and that it thoroughly digests its
food, it seems highly probable that the mole, in re-
spect of gluttony, altogether beats the bat.

Whenever a mole is killed, its stomach is almost
sure to be found crammed full of worms, some of
which show every appearance of having been
swallowed whole. The only record presenting any ap-

Nov., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

271

proach to a definite estimate of the amount of food a
mole will consume in a t;i\en time appears, however,
to be one furnished a ijood many years ago by the
late Mr. E. R. Alston, an accurate student and ob-
server of British and other mammals, .\ceordinij- to
this statement, a mole kept in captivitv devoured in
the course of a sintjie day an amount of food estimated
to considerably exceed its own weii;ht. Durinij the
first three days of its captivity it consumed three or
four dozen earth-worms, a larijc frot;, a c|U,intity of
raw beef, the body of a turkey-poult, and part of that
of a second, as well as one or two bl.ick beetles. It is,
of course, a t;r>-';'t P'ty ''i-'t ^n accurate record of the
weight of the food thus devoured was not kept, but
it is quite evident that it was enormous in proportion
to the size of the animal by whom it w.is e.iten. .•\nd
the marvel of it all is that the mole, like the aforesaid
fruit-bat, does not appear to become " stodged " after
meals of this description, but in a very short lime is
perfectly prepared — nay anxious — to commence afresh.

Our last instance of voracity in mammals is taken
from the cetacean group, and it is of so extraordinary
a nature that, were it not attested bv a naturalist of
high and unimpeachable authority, it would appear
absolutely incredible. The species to which the
anecdote relates is the so-called killer-whale, or
grampus (Orca g^ladiaior), a highly carnivorous and
formidably-armed creature, black and white in colour,
and conspicuous on account of its tall dorsal lin when
swimming near the surface. It is a by no means in-
frequent visitor to our coasts, and is the only cetacean
that habitually preys upon warm-blooded animals. In
length it varies between about 16 and 25 feet or rather
more. No statement as to its weight has apparently
ever been published, but, as a very rough estimate,
this may be set down as about four or five tons. Ac-
cording to the w-ell-known Danish naturalist, the late
Professor Eschricht, one of these killers is known to
have swallowed four whole porpoises in succession ;
w'hile from the stomach of a second, about 21 feet in
length, were taken the remains of no less th.in 13
porpoises and 14 seals in a more less digested condi-
tion ; the brute having been apparently choked by the
skin of another seal, parts of which were found cling-
ing to its teeth. In quoting the latter half of Professor
Eschricht's statement, some writers (notably Mr. F. V..
Beddard, in his " Book of Whales ") omit .ill refer-
ence to the more or less digested condition of the seals
and porpoises, so that it reads as though 14 entire
specimens of the former and 13 of the latter were ex-
tracted from the creature's interior, which would be a
manifest impossibility. As it is, the statement that
four porpoises were swallowed in succession is difficult
enough to credit, seeing that a full-grown specimen of
these cetaceans measures about five feet in length.
There can, however, be no doubt that the killer is an
unrivalled glutton among the larger mammals.

•As regards birds, two or three instances must suilice.
The common cormorant (Fhalacrocnrax carbo) is the
very tvpe of gluttony, and when gorged, these birds, it
is said, will not infrequently continue fishing, although
too full to swallow another fish. .After a full meal,
cormorants may frequently be seen sitting motionless
on a ro(-k for hours, with their wings half extended, as
if " hung out to dry." Soon, however, they recover
their appetite, and begin to renew their pursuit of
prey. The amount of fish a cormorant will destroy
during a season must be enormous, and there can he
no doubt that the numbers in which these birds exist

on some parts of our coasts forms a very serious
detriment to the fishing interest.

I'elicans are likewise exireiiu-ly gluttonous birds, as
are .also the great adjutant stoiks of India, which, till
some years ago, formed such valuable sc.-ivcngers in
Calcutta during a considerable part of the vcar, where
they might often be seen standing stolidly on the
nhiidoii in a more or less completely gorged st:ite.
It used to be commonly s.aid in r.-ileutl.i that
;in .-uljutant would swallow even so large a niouth-
ful as a dead cat at a single gulp, and there is every
reason for believing th.it the statement is founded
on fact.

Many instani-es of gluttony ni'ighl doubtless be
found among the lower anim.ils, and cases of the
crocodile and the common pike might be cited
among such; but to do this would entail :i consider-
able amount of space without .iny real increase in our
knowledge, bi^yond that which is conveyed in the
foregoing Instances.

What" the special object of the development of
gluttonous habits in certain particular kinds of animals
may be is very dilTicult to conjeclure. In the case
of the mole, which is a very active animal belonging
to an aberrant and specialised group, it is_ C|uite easy
to understand why an unusually liberal diet may be
essential; the diniculty comes in with regard to creatures
like the glutton, which differ in no essential features
from many of their relatives, who are content with
a comniiss.iriat of a moi'e moderate type.

^^^^^^

The ColoroLtiorv of
Nestling Birds.

By W. P. I'vcRAiT, A.L.S., F.Z..S., &c.

PaLrt I.

IM the pages of " Knovvikdge " for last year, some
may remember, I propounded a theory to account for
the differences which obtain between the young of
nestling birds in the matter of their activity at the
time of their escape from the egg. I propose now
to follow this up with a few suggestions as to the
probable significance of the coloration of nestling
birds.

This subject falls under two different heads : (a)
the coloration of the body as a whole ; and (ji) the
coloration of definite regions of the body. ^ Under
the first section we have all those birds which are
nidifugous, or active from the moment they leave
the shell, and some nidicolous or helpless birds.
These all agree in that they are downy, but they
present different types of coloration, all of which,
however, belong to the protective resemblance
group. Under the second we have some of the
downy forms, and those nidicolous or helpless types,
which, though generally coming into the world blind,
naked, and helpless, yet frequently exhibit brilliantly
coloured markings, generally confined to the mouth.
These coloured areas belong to another category,
and will be discussed in a future paper.

The down-clad nestling, there can be no doubt,
represents the more primitive condition, but it is iiot
so easy to determine whether in any case the primitive
type of coloration has also been retained, or whether

272

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

what appear to be instances of primitive coloration
are really cases of adaptation to environment indepen-
dently acquired.

That the dominant type of coloration among; primi-
tive animals took the form of longitudinal stripes
seems to be a very wide-spread belief. These stripes
are next supposed to have given way to spots, and
these latter either became re-arranged to form trans-
verse stripes, or mottling-s, or disappeared altogether,
leaving a perfectly uniform coloration unrelieved by
any markings, or at least any very conspicuous mark-
ings such as form a pattern. This orderly sequence
seems to imply that these patterns have followed a
preordained line of evolution; and that whatever the
cause of their origin may have been, the later phases
arising therefrom develop independently of the en-
vironment. This is by no means a generally accepted
view.

Eimer supposes " that the fact of the original pre-
valence of longitudinal striping might be connected with
the original predominance of the monocotyledonous
plants, whose linear organs and linear shadows would
ha\e corresponded with the linear stripes of the
animals; and further that the conversion of the striping
into a spot-marking might be connected with the de-
\elopment of a vegetation which cast spotted
shadows. It is a fact that several indications exist
that in earlier periods the animal kingdom contained
manv more striped forms than is the case to-day."
" This supposition," he goes on to say, " is also sup-
ported somewhat by the fact ' that at present strongly
spotted forms mostly occur in places with spotted
shadows, the longitudinally striped more in grassy
regions. . . . Cross-marking is perhaps to be
connected with the shadows, for example, of the
branches of woody plants — thus the marking of the
wild cat escapes notice among the branches of trees.'

That these several types of markings are, in many
cases, direct survi\'als enjoying a transient existence,
like many other vestigial characters, is highly prob-
able, Init in others thev, with almost equal certainty,
represent comparatively recent developments.

Thus the spots in the young lion and the faint traces
thereof in the adult female are almost certainly
remnants of an earlier and more emphatically spotted
phase common to the adults of both sexes. But it is
surely possible that in many cases these markings may
be remnants of an earlier spotted immature stage when
the young derived benefit from the protection these
markings afforded. In such cases the adults may
have been quite differently coloured ?

The possibilitv that the coloration may, in the
ancestral forms, ha\e been of one type for the adult
and another for the immature stages, and that the
ancestral immiiture stages may be reproduced at the
corresponding period of development to-dav, is one
that seems not to h;i\e received fair consideration.
Evidence in l,i\our of this view- will be submitted
presently.

According to the prevailing opinion, we have some-
thing like a recapitulation of past types of coloration,
the markings of ancestral adult stages being repro-
duced in the immature stages of to-day. On this as-
sumption we must suppose either that this immature
coloration is now of no protective value, or that the
descend.ints of these spotted or striped forms, .as the
case may be, require the ancestral adult protective
colours only duiing the period of immaturity ; or that
this coloration belongs to the class of correlated varia-
tions and has no significance in a large number of
cases.

But even this view cannot be reconciled with
Elmer's intreprctation of the significance of these
markings. If longitudinal stripes are the result of
adaptations to foliage of monocotyledonous plants,
and spot marking to an adaptation to foliage of vegeta-
tion which cast spotted shadows, then the longitu-
dinal markings of many animals of to-day must be
quite out of harmony with their environment, and their
survival shows that in these cases at least the corre-
spondence between the markings and the type of
foliage need not be a very close one, since the longi-
tudinal stripes developed to harmonize with linear
foliage serves ecjually well amid foliage which casts
spotted shadows.

Transverse stripes, at least, it must be admitted, owe
their origin to adaptation to totally different environ-
ments. Originallv de\'eloped for the sake of affording
protection amid linear foliage, as in the tiger, for
instance, they ha\e almost certainly been acquired
Je novo in the case of the zebra, where they serve to
protect the animal on account of the absence of foliage
of any sort.

The contention that longitudinal striping was de-
veloped in response to linear foliage is lacking in
cogency. Vertical stripes would have served the pur-
pose better, supposing that the direction of the stripes
was a matter of prime importance. The widespread
occurrence of longitudinal stripes probably depends on
a deeper stimulus.

The definite and orderly sequence of colour, which
many animals exhibit in the course of development,
seems to show that in many cases the markings of the
immature stages are really reproductions of an
ancestral adult livery. This is well seen in cases
where the male and female have a distinct livery. Here
the females and young are often precisely similar in
dress, and bear a remarkably clo.'^e resemblance to the
adult stages of both sexes of more primitive but closely
allied species. Among birds there are many illustra-
tions of this. A large number of animals, however,
afford no clue as to whether the colour of the im-
m.iture indi\idual is ancestral or newly acquired ;
whether it is an ancestral adult or an ancestral juvenile
coloration. The larval Alpine Newt, for example, is
conspicuously longitudinally striped. Even while still
within the egg these markings can be seen. There is
a median dorsal black stripe which bifurcates on the
head, and a lateral stripe, also black. Later, black
pigment cells wander into the transparent ground
colour, and eventually the black upper and red under
surface of the adult is acquired. The stripes of cater-
pillars are not easily accounted for. Are these in-
dependently acquired markings, or inherited ancestral
larval markings? They certainly can have nothing to
do with the adult coloration.

With the birds the problem becomes still more com-
plex, inasmuch as, in the precocious types at least, we
may have three separate plumages : (a) the nestling ;
(b) of the fully-flcdgcd " immature " stage, which may
be the same as that of the female ; and (c) the adult
stage, i.e., the plumage worn by the male only, or by
both sexes.

With regard to the " immature " stage it is worthy
of comment that, as Prof. Newton has pointed out,
" Throughout the class Avis it is observable that the
voung, when first fledged, generally assume a spotted
plumage of a peculiar character — nearly each of the
body-feathers having a light-coloured spot at its tip —
and this is particularly to be remarked in many groups

Nov., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

273

of the oscincs. ..." Concerning this fact, \vliich ap-
pears to have been first indicated by IJlyth half a
century ago, \vc may have more to say on another
occasion. Just now we desire to draw especial atten-
tion to the plumage of the nestling, which does not
appear to have previously occasioned comment.

There seems to be strong presumptive evidence to
show that the primitive coloration of young birds
took the form of longitudinal stripes. Nowhere arc
these stripes seen to better perfection than in the
young of the Kmu. Here, in the very. young bird, we
find a long, thin, white stripe extending from the head
down the back of the neck, and tailwards along the
back on either side of the middle line. Below the
trunk-stripe a second occurs, but towards the end of
the nestling period it is interesting to notice these
stripes appear to increase in number. 'Ihc second,
inferior trunk-stripe of the newly-hatched bird now
extends forward to join the neck-stripe just described ;
and beneath the second, now elongated stripe, a third
appears, and this runs upwards to form a second

Pig. I. — The ncstlinj; of the .Mo<iruk Cas50\\ar>' \Ca^ua>iii.t htii'illi),
showing .«;trongl\ marked longitudinal u hite stripes on a dark chestnut
background. Only faint tracesof stripes are present on the neck, hut
in the Emu they are very conspicuDu.s.

the tips of the rami of each down feather are pr, duced
into long ribbon-like horny processes. But th ,e can
be little doubt but that this peculiar structural modi-
fication of the down feathers is comparatively recent,
since, though these no longer display a pattern, the
down feathers of the neck agree precisely with those
of the I'-mu, in that they ;ue coloured so as to form
very strfingly-marked longilndinal stripes down the
back of the neck, while along the Iron! of the neck
and the sides of the head these stripes gi\e pla<'e to
rows of dots.

.\pteryx, it may be mentioned, has .1 miifonn grev
coloration.

There is no reason to believe that the Grebes are
even remotely related to the Ostriches, yet the nestlings
of these birds di.splay a precisely similar style of colora-
tion— light longitiiflinal str'ipes on a dark ground

It is interesting to note that while in the nestling
plumage of the " Ratile " birds .and the (irebes we
iind a relatively large number of stripes, in all the
forms now to be considered the pattern is almost in-
\';irial)lv formed bv a metlian and two l.ilcral stripes.

Fig. 2.— The nestling of the Great Crested Orel>c U'luli'-ii'f: erislalin).
The neck stripes are llere strongly marked, as in the Rmu.

neck-Stripe, running paridlel with the first ; below
this third a fourth stripe appears ; this extends from
the end of the tibia, upwards and forwards along the
flanks, terminating at the base of the neck. The
continuous neck-stripe, \f). i, breaks up at the base
of the skull into a number of dots in this older bird.
In the very early stages the legs bear curious mottled
markings, but these rapidly vanish.

In the young Cassowary (Fig. i), at an age roughly
corresponding to the second stage of the Emu, only
the faintest traces of spots on the head and neck are
traceable. On the trunk we find five white hands
sharply defined and set off by a darker ground than in
the Emu. The fifth corresponds to the leg and flank
stripe of the Emu, but is shorter.

In the nestling Rhea stripes also occur, but these
are less conspicuous and fewer in number than those
of the genera just described. The neck-stripes arc
obsolete.

The nestling Ostrich appears to differ from the other
" Ratites " in having a uniform coloration. The
trunk, it will be remembered, presents a curiously
grizzled appearance, and this is due to the fact that

In some species these stripes are stronj^ly marked, in
others barely traceable.

But great variability in this matter olitains, even
among the several species of a single family. In the
Tinamous, for example, a medi.an stripe along the back,
extending forwards up the neck on to the head, and a
dark stripe behind the eye, occurs with some fre-
quency. Other of this group are uniformly coloured,
or have a dark occipital i^atrh (yol/inciTcits). In
Rliyudidlii'i the head and ni-ck are spotted, as in the
nestlings of the Ostriches.

The game-birds are undoubtedly, as a group, striped
when nestlings, though in many this striping is giving
way to mottling by the breaking up of the stripes.

The nestling Curassow, e.g., Crax alector, is
conspicuously banded. The mid-dorsal line is marked
with a broad dark chestnut band, tended on either
side by a conspicuous white stripe ; the band com-
mencing on the head, and widening backwards. The
white bars also commence on the head. Again, in the
voung Argus Pheasant we have a similar dark median
band bounded by white stripes. In the young Black-
cock (Lynirus iclrix) the gener.al ground colour is buff,

274

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

the back of the neck bears a median stripe which
bifurcates at the trunk to run down on either side of
the middle Hne in the form of two indistinct Hnes.
The occiput and the rump are of a warm chestnut
colour. But the general effect of this pattern is
mottled rather than striped. This mottling is more
pronounced in the Capercailzie nestlings, and in those
of the Pheasant and Partridge ; probably this mottling
is derived from the breaking up of sfri|3es ; the last
phase of the striped dress being seen in the nestling
Red Grouse.

The nestling stages of the t'hardriifurmes, or at
least the Limicolw and Lari, appear to ha\c been
originally striped. To-day these stripes are most ap-
parent in the Redshank, Woodcock, and Norfolk
Plover {(Edimciiiiis crcpilaiis). In the Redshank we
find a narrow median dorsal stripe extending forwards
up the neck and bifurcating on the crown of the head.
On either side of the median stripe are three lateral
stripes — these stripes are dark on a buff ground. In
the Woodcock the median stripe takes the form of a
broad chestnut band. The lateral stripes are wanting.

Fig. 3.— The nestling of the Common Sn\ifl2 ytj lUuuign c,ilc^tts\. There is
asecond nestling between that in the foreground and the adult. Note
how the stripes in the adult harmonize with the ribboo=like leaves
of the grass.

The .Snipe, however (I'ig. 3), is distinctly striped.
In dalliHagi) calcsln (the Common .Snipe), lor example,
the general colour of the down is of a rich dark chest-
nut, relieved by three \erv distinct white stripes. The
;idult is also, it may be remarked, longitudinally
striped. The Norfolk Plover has the ground colour
of the body of a pale yellov^ish grey, relieved by two
narrow black bars or lines along the back, and a black
stripe through the wing and down the middle of th.e
head.

In the other Plovers the stripes h.ave broken up to
form mottlings as in tin* (lulls. But the general
cdloration is obviously adaptive — procryptic. Thus, in
the Kncit — which breeds in the snow — the down is
white, mottled with grey ; the young Kentish Plover
has the upper parts \ cry pale Iniff, powdered with
black ; and so on. The under parts, as in the case of
nearly all nestlings, are eillier pure white or nearlv so.
Tlv |ac;ma bears strongly-<K-llncd narrow black stripes
(in .1 bright chestnut groinid.

i'he Culls, like the Plo\ers, show lioth striped and
mottled forms, the former being rare. Indeed, so far,
the only striped form I ha\e come across is the nestling

of the Little Tern. The ground colour in this species
is pale relieved by a median and two lateral stripes.
From this we pass to the mottled type, and in many
cases, e.g., Common Gull, the median and lateral
stripes are still plainly visible ; the neck, too, is spotted
just as in the young of Droma'us, also indicating the
derivation of the spots from stripes. The young
Sootv Tern is almost unicoloured, powdered with
minute white points ; and from this we pass to the
completely unicoloured and dark young of the .Skuas.
The Skuas, it is to be noted, are of a uniform dusky
colour.

The Gruiformcs would appear to have been origin-
ally striped, inasmuch as traces of a broad medi;in
band are visible in the young Japanese Crane, while
the young Bustard (Otis tarda) bears a close re-
semblance to the young Gull, being pale-coloured with
dark mottlings.

The voung of the Turnices are striped.
The nestling Rails at the present day are all dusky
in colour, yet the young of the Black-tailed Water-
Hen {'Microti-ibpiiyx veniralis) shows distinct traces of
a median and two lateral stripes.

The .Anseriformes, like the Rails, have now typically
uniformly coloured nestlings. .As a rule the upper
parts are dark, the central light. But the young of
the Mallard and its near allies have their upper parts
relieved bv light-coloured spots — one over the thigh
and one behind the wing. In many Anatidse there is
a strongly-marked superciliary streak, and a streak
passing from the lores to the eye, and behind this to
the base of the skull. These markings appear to be
remnants of an earlier striped condition. The Shel-
drakes depart from this type, having a broad dark
median band which passes upwards along the neck and
invests the whole of the upper part of the head. A
dark patch behind the wing gives the semblance of a
white streak on either side of this median band. In
the \'ariegated .Sheldrake (Casrirca raricgata) the dark
median band expands over the shoulders to form a
transverse band. Whether this peculiar coloration of
the downy Sheldrake is a modification of an earlier
striped condition or a specialised condition it is not
easy to say, but it seems probable that the latter is the
case. The under parts, as in all the other Ducks, are
white. The downy young of Swans and Geese, and
of Chauna display no markings, and are either pale
grey, or pale yellow in colour.

We come now to a number of groups in which the
young appear to be invariably uniformly coloured.
But, it is to be noted, these young are all nidicolous —
born blind and helpless ; and it may well be that these
have long since lost the ancestral striping. Many are
reared in holes, and in those which lav in open nests
the striped pattern of the down would probably afford
no protection.

The Stcganopodes (Gannets, Tropic-birds, Frigate-
birds, etc.) ha\c the young clothed in white down.
In the Ciconi;e (.Storks) the young may be thickly
clothed «ith long white down, or thinlv clad in long
thread-like down feathers, e.g., Herons.

In the Tubinares (Petrels) the down is either white
(.Albatross) or dusky (Petrels). In the .Sphcnisci
(Penguins) it is dark grey or tawny yellow. In the
Colymbi (Divers) dark grey. In the Accipitres it is
white or grey. In the Striges and other Coraciiformes
the down, when present, is either white or grey in
colour.

Among the birds, as in other vertebrate groups,
longitudinal stripes do not necessarily give place to a

KNOWLEDGE & SCIENTIFIC NEWS.

2/5

spotted livery, and tliis to a uniform cohiration. In
the nestlings of the Emu, Cassowary, and Grebe, for
example, the striped dress gives place to one without
markings, and this again to a pafternless plumage in
the adult stage. The Game-birds furnish us with two :
very interesting stages of de\elopment. In some, e.g.,
Quails, the young arc striped ; the first |)ennaceous
plumage — as distinct from the downy plumage — may
be described as a brown or buff colour relieved by vari-
ous shades of darker brown arranged in the form of
streaks, spots, and bars. The adult plumage for both
sexes is similar. In others, e.g., many Pheasants, the
striped downy plumage is succeeded by a dress re-
sembling the immature and adult dress of the Quails.
This dress is retained by the female, but in the male is
succeeded by a more or less resplendent livery. In
other Pheasants, e.g., l%ared Pheasants (C rosso f^lil on),
the speckled dress of immaturity is discarded by both
sexes for one of more or less brilliancy.

The same order of coloration, which obtains in the
life of the individual in one group, is found in another
group only in studying the history of the race. This
may appear to be only another way of saying that the
history of the species is a recapitulation of the history
of the race. Rut in the present connection, it is to be
noted, the most primitive species passes through all the
possible phases in the course of its growth, while the
" race " to which we have referred is of comparatively
recent origin — the Limicoljp to wit. Herein we find
striped forms like the Redshank, or the Snipe, mottled
forms like the Gulls and Terns and some Plovers, and
unicoloured dusky forms like the -Skuas and iXlcida?,
e.g.. Guillemots. In the Terns and Gulls the mottled
nestling gives place to a brown first plumage, which is
succeeded by a more or less unicoloured adult dress
worn by both sexes alike.

Longitudinal markings occur but rarely among
adult birds. Instances thereof are seen in the Snipe,
.-\vocet, Black-throated Di\er, Herons, and Hitterns.
N'ow it is worthy of note that in the Snipe and the
Bitterns, at least, these peculiar markings are known
to be used for protective purposes. The Bitterns when
desiring to conceal themselves adopt a perfectly verti-
cal position, throwing the head and neck upwards and
holding the body perfectly still so that the dark lines
down the neck harmonise with the dark inter-spaces
between the reeds which form its cover. The Snipe
reverses this position, holding the head downwards
and presenting the longitudinally-marked back so that
the tail points directly up\\ards.

From the .'Etiological side it must be admitted we
have much yet to learn in the matter of these stripes.
Where both nestling and adult wear a protective
plumage, it seems strange that in many cases a distinct
livery should be necessary for each stage. But this
may be due to the fact that the environment of the
nestling is quite different to the normal environment of
the adult. The downy young Ringed Plover, for ex-
ample (JEgialitis hiaiiadd), is almost white with dark
mottlings ; the adult is buff-coloured above, white
below, and barred across the head and breast with
black. These bars are apparently protective devices,
for while the kahki-coloured body is invisible, the dark
bars are conspicuous, but they bear a curious re-
semblance to mussels, the empty shells of which occur
on every tide-wash, where these birds commonly feetl.
But there is no need to expect a very close connection
between the two stages in the life-history, for while in
many cases tiie stripes of the downy plumage may well
be ancestral, and, therefore, of extreme antiquity, the

plumage of the species is necessarily of more recent
origin, and is determined by the re(|uirenients of the
environment amid which it has t!e\ eloped.

Finally, wc are brought to tlie question of llie origin
of the stripes. Their remarkably wide-spread
occurrence among vertebrates suggests that they must
be due in the first place to some deep-seated
physiological activities, which determined the de-
position of pigment in certain delinite areas, serving
either as centres of distribution or as screens for the
protection of sensitive regions Irom excessive light.
The reasonableness of this latter view is supported by
the fact that these stripes occur with striking frequency
in " larval " forms, such as of fish and tailed
.Amphibia, where the bands of pigment over-run the
brain, spinal cord, and lateral line organs. Their
occurrence in higher vertebrates would seem to
decidedly weaken this hypothesis ; but it may be that
the ancient fashion of laying down pigment is for some
reason or other adhered to in these groups, just as
gill arches, no longer useful, are also de\el()ped.

It seems hardly likely that these stripes in the case
of the birds have been independently acquired, and
acquired afresh, too, in each group, at least, in which
they occur, solely in response to the need for a protec-
tive livery of this particular type. But the adoption
of this livery as a method of salvation ready to h.-md
seems probable enough.

The existence of whole-coloured forms seems to ha\e
been due cither (a) to the suppression of the stripes in
favour of a \et more protective dusky livery, as in the
case of the voung W'aterhen (p. 274), where they are
just traceable, or of the grizzled covering of the young
Ostrich — which retains the original neck-stripes lost
in the Cassowary and Rhea — or f;3) to the suppression
of pigment to secure a white covering, as in the case
of birds which, being nidicolous, lie helplessly exposed
in open nests to the glare of the noonday sun, and
thereby derive benefit from a white covering. That
there is some probability in this suggestion is shown
by the fact that the Common Buzzard has contracted
a habit of erecting a shelter of green boughs above its
nest, replacing these as soon as the leaves wither.

The question is full of interest, and demands further
study.

REVIEWS OF BOOKS.

Scientific Pact and Metaphysical Reality. — It has lately been
remarked that in tho disturbance of cxistinf; theories which
has been produced by the determination of new facts in
physical science, there .are few hypotheses which seem totally
unworthy of consideration, and few speculations that are, not
valid. One mif,'ht note as an accompanyinj.; phenomenon, that
the scientific world seems to have been stirred at the same
time by a desire to investigate, not the relations of matter and
energy alone, but of mind and energy, and to formulate in as
ex.act a manner as its knowledge will allow the relation of
mankind to its own fate and destiny. Some such design is
apparent in both of two books, of widely different seojic,
which are before us — " Scientific Fact and Jfctaphysical
Reality," by Robert Brandon Arnold (Macmillan), and " Ideals
of Science and Faith" (George Allen) in which the Rev. J. I'".
Hand collects the essays of writers who approach the problems
of man's life or immortality from such widely diflVrent stand-
points as those that we expect to be assured by a physicist
like Sir Oliver Fodee, a biologist like Professor J. Arthur
Thomson, a psychologist such as Professor Muirhead, or
educationists, theologians, or divines like Professor Geddes,
the Rev. John Kelman, the Rev. Ronald Bayne, or Mr. Wilfrid
Ward. The value of such opinions, and of such an assem-

276

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

blage of opinion, lies in its power to induce people, whose
views are as wide as tlie poles asunder on spiritual matters,
to lend an ear to that which other people are thinking.
Tliere are many people, sane, high-minded, and cultured,
to whom the opinions expressed by Sir Oliver Lodge on the
scheme of creation will seem as heretical as any that ever
sent a man to the faggot and fire ; and there are others, not
less kindly, conscientious, or tolerant, to whom the reading
given by clergymen of the importance of religious tenets must
seem illogical to the verge of puerility. There are beyond
these two classes of people — like rays in the ult in -violet or
the iH/ra-red — other thinkers who genuinely believe that it is
wrong to teach what they call superstition ; and other, and
equally worthy people who regard doubt of the Old Testa-
ment as blasphemy. If the prospect of seeing their own views
.stated induces any member of any of these classes of people
to buy this book, it will probably lead him to read the opinions
that are stated side by side with them ; and that is all to tlic
good. In this sense Mr. Hand's collection has a great educa-
tional value, and of its interest there can be no doubt.

The other book which we have joined to his for the purposes
of this review, " Scientific Fact and Metaphysical Reality," is
of a different kind, and demands a different kind of intellectual
equipment for its appreciation. It is, as we take it, an
attempt to state, if not to reconcile, some of the eternal dif-
ferences which are to be recognised between man's conception
of the material universe and the in.'stinctive denial of his own
insignificance in it. " The stars ... by their double
scale, so small to the eye, so vast to the imagination, seem to
set before man the double nature of his character and f.ate,"
wrote K. L. Stevenson. Mr. R. B. Arnold endeavours to
disentangle the paradox of man as a mere collocation of living
cells; and of man created by God for immortality as he has
believed himself to be. Mr. Balfour, in his recent Presidential
Address to the British Association at Cambridge, sought to
exhibit the contradiction between the physicist's theory that
motion was matter, and man's instinctive disbelief — something
akin to Nature's abhorrence of a vacuum — in anything which
should persuade him that matter was a mere state of motion-
that—

The stately palaces, the Eolemn temples,

The round world .
could dissolve like the baseless fabric of a vision, and leave
not a wrack behind. Mr. Arnold's intention is not to exhibit
the paradox, but to reconcile its antitheses ; to show, in short,
that there may be a scientific reason, not for the grudging
admission of the possibility of a superior Being's existence",
but for the acknowledgment of a Divine purpose and a Divine
future for man's soul. We are not sure whether Mr. Balfour's
paradox was sounder than most paradoxes, since the very
latest theory of the physicists is, after all, but a tentatively
built model of the universe which is of the most temporary
value. Theories are only to explain things we do not under-
stand. They are not immortal truths. And if Larmor's and
Thomson's and Lodge's modern cosmogonies are only tem-
porary structures, we are not very sure of the value of
anyone's theories of God and immortality. But the theories
are always interesting, and Mr. Arnold's exposition and his
philosophy are exceptionally so.

The Science and Practice of Photography.— By Chapman
Jones, F.I.C., F.C.S., F.R.P.S. Fourth edition. Rewritten
and enlarged (London: Iliffe and Sons).— The new edition
of this well-known text-book is in many respects better than
the earlier editions. It has been not merely brought up to
date, but re-written, so that, although it is arranged on the
same general lines as before, it is practically a new book. Of
those parts that are obviously new, we notice especially the
chapters on the modern organic developers, the nature of
their constitution, and the methods of their use; the most
lecent lenses and the priticiples involved in their construc-
tion ; the nature of the developable image ; the newer
printing methods, such as the X'elours-Artigue, gum bichro-
mate, ozotype, and Ostwald's c.atatype jirocesses ; and chapters
on photographic measurements and the more exact testing of
photographic plates, besides pages on sensitometrv, acti-
nometry, shutters, the illumination of the dark room, and
many other subjects. In some cases where the subject dealt
of is on the border line of what may be called pure photo-
graphy, references are given to enable the student to continue
his study of the matter if he should desire to do so. .'\lthough

the book is essentially a student's book, it is also a practical
guide, and those whose knowledge of chemistry and optics is
slight will find at least a very appreciable help towards under-
standing the principles of their work as dealt with here in the
few pages devoted to the exposition of the fundamental
principles of these sciences as applied to photography. The
general arrangement of the volume, with the significant head-
lines to the pages and copious index, facilitate reference to any
desired subject. It is an invaluable book.

The Heart of a Continent. — The publication in a cheap edition
of Colonel Vounghusband'sbook. " The Heart of a Continent "
(John Murray), comes at a most opportune moment. Not
only because its author, as the hero of the Thibet Mission, has
a special claim on the interest of the public just now, but
because the travels described in " The Heart of a Continent"
took place partly in the scene of the present Russo-Japanese
War, as he visited Mukden and Kirin, and travelled through
Manchuria. It would be difficult to have a more agreeable
cicerone than Colonel Vounghusband ; his fine intelligence
illumines all he touches, and the entire absence of prejudice
with which he treats all he describes gives it a special value.
We will quote as an instance the following comparison
between the English and Russian Armies : " An English
soldier is perfectly right when he has shaken down on active
service, but in barracks he produces the impression that his
dress is his main interest in life. A Cossack, on the other
hand, whenever one meets hitn, looks as if he were ready to
buckle to and fight then and there, and certainly dress or
appearance is the last thing in the world he would trouble his
head about."

A History of South America. — In his " History of South
America" (John Murrayi, Mr. Charles Edmond Akers has
admirably executed a most useful piece of work. Up till the
appearance of this book, there was no general history of South
America in existence; and the seeker after information had to
glean his facts with pain and toil from writers of divers
authority and nationality. Mr. Akers has provided in one
m.oderatc-sized volume a concise yet readable history of the
South American Republics down to the present day. He has
dealt in greatest detail with the events of the last fifty years,
but the emancipation of Spain's Colonies is briefly described,
and an introductory chapter relates the history of the Spanish
Conquest. Subsequently Mr. Akers deals separately and at
length with the histories of individual States. In a narrative
that is of necessity so condensed there is not much scope for
picturesqneness. The story is one of cruelty and oppression,
bloodshed, and revolution, but it is told tersely and dispas-
sionatel)', though Mr. Akers is a little too much inclined to
judge medieval adventures by the standards of to-day. Here,
for instance, is his estimate of the Spanish Colonists : " The
national character had been formed under malignant influences,
and the outcome was narrow-minded fanaticism, carelessness
as to human life, despotic conduct towards all of lower rank,
an absence of any impartial sense of justice. A lower stan-
dard of the relation of man to man, a narrower conception of
public morality, it would, even in those days, have been diffi-
cult to find anywhere. It was from the scutii of this fanatical
population that the first Colonists came." Mr. Akers goes on to
describe very briefly the ever-to-be-regretted destruction of
Inca civilisation, one of the greatest tragedies of history.
The chapters that follow are a remarkable achievement in
their concise and well-proportioned marshalling of facts in
which one dominant personality after another comes to the
front and is coiispicuous ; and here great interest is added to
the book by the portraits of leaders and presidents from
Simon Bolivar onwards — men with strongly-marked features
and rough exteriors. " Glancing back over the period which
this history covers," says Mr. Akers, in conclusion, " there is
everywhere the sense of human sacrifice, the all-pervading
smell of bloodshed, no matter whether the country under
review is Argentina, Brazil, Uruguaj', or Paraguay. If
these Republics would suppress their military establishments,
and rid themselves of the armaments they have collected,
tranquillit}- would be ensured. They arc fond of posing as
nations while still in their swaddling clothes. The possession
of great stores of war material is a temptation to try conclu-
sions with their neighbours." But even in this respect Mr.
Akers thinks itnprovement is noticeable, and there is a grow-
ing desire for internal and external peace. What is necessary
for the consolidation of peace is the " adequate administration

Nov., 1904.]

KNOWLEDGE cS: SCIENTIFIC NEWS.

277

riglits, and ;i more liberal system ot cdueatiuii." No j^roat
ability, no extraordinary efi'ort, no costly expenditure oi money
is necessary to achieve these results.

Across the Great St. Bernard. — Mr. A. R. Sennett is pos-
sessed of a facile and llnent eloquence, which he exercises
with much effect in " .Vcross the Great St. nern.ard " (I'.emrose
and Sons). .-Mpine climbing is a subject which naturally
affords scope for picturesqueness, and if the reader can over-
look a too exuberant tloweriness of style, he will find sincere
enthusiasm, much interesting matter, and a genuine gift of
observation on the part of his author. Mr. Sennett is a
dauntless cyclist, and, wherever it was possible, his journey
was performed by that means. Among many curious points
of interest he raises is that of the curious physiological pheno-
menon, peculiar to high altitudes, known as maldeniDn-
tapie. Its symptoms are described as follows: "Within an
hour of the hospice I was sei2ed with mal-de-montagne. . .
My throat was dry, my head ached, as did my limbs ;
in the most unexpected manner I dropped in the snow,
with an overpowering desire to sleep there and then." This
form of seizure has been investigated by Professor Mosso. of
Turin. He found that it generally began at a height of i.;.ooo
or 13,000 feet. The symptoms are an extreme lassitude, with
panting for breath, and sometimes vertigo, with nausea, and a
tendency to syncope. Professor Mosso is of opinion that it is
due not only to a deficiency of oxygen in the blood, but also to
a lack of carbonic acid caused by diminution of air pressure.
and he relieved a sufferer from mountain sickness by giving
him carbonic acid gas to breathe, but M. de Thierry, on the
other hand, states that carbonic acid gas exists in nearly the
same proportion at a height of 12,000 feet as it does 5,ooo feet
lower. It is curious that Mr. Sennett was recommended, by
" the good father of the hospice at Simplon, if we felt faint, to
eat the snow I Because," said he, " you may become faint for
lack of oxygen, and mountain snow contains much air."

An Optical Dictionary. — "The Optical Dictionary" (Gutenberg
Press), edited by Mr.Charles Hyatt-Woolf, is a useful glossary of
optical and ophthalmological terms. It is intended for the use
of students and others ; and includes, in addition to strictly
optical terms, a large numberof words relating to photography
and instruments of precision, as well as mathematical terms,
and a certain number of French and German words in
common use.

A German Grammar. — " Whitaker's Modern Method of Learn-
ing German " (Whitaker and Sons), by C. W. Whit.iker and
H. G. Braun,is intended primarily for the use of students who
are teaching themselves. It contains much useful matter, a
simplified grammar, examples of correspondence and con-
versation, exercises and translations. In our opinion the
authors are mistaken in supposing that a student could obtain
any idea how to pronounce the German language from the
accompanying phonetic spelling in the reading lessons. What
open-minded person, for instance, would imagine that " fair-
gnea-goonks-rry-zer "represented the correct pronunciation of
" Vergniigungsreise " ? While the spelling Mesch for Ich and
leesh for lich are surely unnecessarily misleading.

Trees. — The first volume on Buds and Twigs, Professor
Marshall Ward's series on "Trees" (Cambridge University
Press), is well calculated to fulfil the purpose for which it was
intended — that of providing students of forest botany with a
guide to the study of trees and shrubs from the point of view
of the outdoor naturalist. The author seeks to rectify the
existing neglect of the older methods of observation of the
living plant, " which rendered the study of botany so exhila-
rating to the naturahst of pre-labor.atory days." It is a most
attractive little volume, filled with excellent illustrations. It
is so far exempt from unnecessary technicalities as to make it
suitable for the use of the amateur student of Nature, while
at the same time it also includes an introduction to the study
of systematic botany and morphology, and to what its author
describes as " the expert study of forest botany."

The Storj' of the World. — A wise selection of an elementary
text-book of history for Cape schools has been made by the
Government in " The Story of the World " (Wm. Blackwood),
by Miss M. B. Synge. It is published in five volumes, each
one complete in itself. The first, which is in some ways the
best of the series, tells the story of the world up to the time

1 Julius C;esar. The method adoii[ i :.ii uly

with well-known events .and incidents likely to i[npress them-
selves re.adily on a child's mind ; these are described in a
pleasant, popular style, and brielly connected by a historical
n.arrative. The illustrations are attractive and instructive.
The four successive volumes deal with tlie periods from the
Roman Enipire to the Uen.aissance (\'ol. 11.) ; from the Refor-
mation to the Seven Years' War (Vol. III.) ; and from the
.'Vmericau War to Waterloo, " The Struggle for Sea Power "
(Vol. IV.). A volume on " The Growth of the British Empire "
(Vol. \'.), covering the period from Waterloo to 1903, completes
the series.

Photography.- '■ How to Photograph with Roll Cut Films"
(Hazell, Watson, and Viney, Limited), by John A. Hodges,
F.R.P.S. A good manual for the amateur; should be very
popular. Price is. net.

A New Catechism (Watts and Co.). by Mr. M. M. Mangasarian
Lecturer of Independent Religious Society of Chicago, is an
attempt to give, in (juestion and answer form, a popular com-
mentary upon current beliefs, phenomena, and institutions. It
deals with such subjects as Reason and Revelation, the Church
Creeds and Clergy, Death and Immortality. It appears to be
a sincere attempt to face the essential facts of life.

Key to Godfrey and Siddons' Geometry.— Mr. F. A. Price has
done a useful piece of work in ])re|)aring a " Key to Godfrey
and Siddons' Geometry" (C. J. Clay and Sons, Cambridge
University Press Warehouse). A key is essential to a work
of this Kind, and will treble the usefulness of an excellent Text-
book of Geometry for Preparatory Schools.

Philosophy of Herbert Spencer. — Mr. W. H. Hudson has re-
vised and partly rewritten his" Introduction to the Philosophy
of Herbert Spencer " (Watts and Co.), which now appears in a
cheap and popular edition. It is intended as a guide to the
study of the Synthetic System, rather than a summary of it;
it also includes a biographical chapter. It is written in as
clear and popular a style as is consistent with the subject.

Second-Hand Books. — From Messrs. John Wheldon and Co.
we ?iave received a copy of their newly-issued list of miscel-
laneous books, in which, we notice, the various branches of
science are well represented.

Physical Apparatus — Messrs. F. E. Becker and Co. (W. & J.
George, Limited, Successors) have sent us a copy of their new
list of apparatus in the various departments of Physics, in-
cluding Sound, Light, Heat, Magnetism, Electricity, Mechanics,
iS:c. This exhaustive catalogue consists of over 600 pages and
some 4000 illustrations. One of its notewortliy features is
that the reciuirements of science teaching in this country and
its Colonics are always kept in view, and the articles listed
cover the latest developments in their subjects. The method
adopted in the list itself, together with the completeness of tlie
index, is such as to make reference to it simple and expe-
ditious.

Brooks' riexible Curves.— Mr.

Street, sends for our inspection

W. J. Brooks, of Fiti;roy
the devices which he has
patented for assisting
draughtsmen to draw
experimental curves.
These devices are three
in number — a flexible
strip of celluloid or
steel providc:d .along its
length with tabs which
can be held down by
the fingers, a steel
strii) to which any shape can be given by means of a stiff-
hinged linkwark that is attached to the tabs and holds them
permanently in position, and an elaboration of a siinilar
principle suited for drawing long curves. In this third
pattern light wooden cross-bars hinged to the tabs slide
through brass spring-clamps, and are thereby hcM friction-
tight against a long wooden bar running like an abscissa ol
the curve. These devices, together with one or two modifica-
tions and accessories of thein, are as practical as they are
ingenious, and will be found of great service to architects,
designers, engineers, or experimenters in mathematical physics
and to draughtsmen generally.

278

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

Conducted hy F. Shillington Scales, f.r.m.s.

CoccidoLe.

With Notes on Collecting and
Preserving.

By Alice L. Emlilhton, B.Sc.

{Continiud from page 251.)
I-KOM lliis laricl .sketch of some of the puints in the
life-history of Comys mfelix, it can be gathered that
very special microscopic methods are required to do
such a piece of work on Coccid parasites. It has been
found that the eggs can be sectionised while still in the
abdomen of the fly. The best fixing reagent has been
found to be Gilson's fluid (the formula for which will
be found in a footnote), used cold. The specimens

Formula for Gilson's Fluid : —

Nitric .\cid, 46° .. .. .. i9'5 cc.

Glacial .\cetic Acid .. .. 55 cc.

Corrosive Sublimate .. .. 23 75 cc.

Alcohol, 60 per cent. . . . . 125 cc.

Distilled Water . . .. .. noo cc.

were left in nearly half-an-hour, then washed very
thoroughly in 70 per cent, alcohol, and so gradually
taken to absolute alcohol, cleared in cedar wood oil,
and fixed in paraffin (not too hard — certainly not more
than 52 degrees melting point). The sections give best
results for nuclei of eggs when stained by the iron-
akmi-ha-m.-itoxylin method, with eosin as the second
stain ; the nuclei in such preparations show their struc-
ture very clearly, and the mounts are permanent.
The youngest little white larvee are best seen in water
or dilute glycerine, the trachea;, then remaining full of
air, show up dark and well-defined. For some struc-
tural points it is well to treat them with very weak
osmic acid, or, better still, expose them for a minute or
two to the fumes of osmic acid over the mouth of a
bottle containing it. It is inadvisable to use alcohol
with these larvse, as they shrink, and very little can be
ascertained from such specimens. Some aqueous
stains take well on these larvcP, but on the whole those
mounted in water or dilute glycerine, unstained, seem
the most satisfactory, though they have the disad-
vantage of not being permanent.

The crystal-containing envelopes are best seen by
polarised light. The microchemical tests to prove
these crystals to be uric acid also need special care and
methods. Many of the other points in such an
investigation as this must be confirmed by means of
serial sections, to prepare which it has been found best
to fix the specimens in Gilson's fluid, the nitric acid of
which serves to soften the chitine. \'arious stains may
be used, hut to see nuclei the iron-ha'matoxvlin and
cosin will be found to be as good as any — or with
(jrubler's orange G instead of eosin.

The above gives an inadequate account of the
methods of investigating some of the finer points in the

developing and life-history of a Coccid parasite, but,
perhaps, it would not be out of place here to give some
general directions for collecting and preserving Coccidae
themselves. Such directions have been given over and
over again by entomologists of all countries for the
collecting and preserving of Coleopicra, Lepidoptera,
etc., but Coccidae are not, and never have been,
favourite insects for the collector, and so it may not
be superfluous to give here some notes as to the best
methods to be employed for collecting and preserving
these interesting but much-neglected creatures. They
differ so widely from other insects that special methods
are necessary. There is a great field for the collector
in Coccidology, as collections have been made from
very few parts of the world, for, whereas very repre-
sentative collections exist of other insects from North
and South .'\merica, most European countries, Africa,
New Zealand, and India, yet the Coccidae are practically
unknown. The collections that do exist are at best
very local and very incomplete. This is all the more
extraordinary when one remembers how destructive
Coccidae are, especially in tropical countries, where they
are conspicuous on almost every plant. This neglect
has not come about because these creatures are in any
way specially difficult to deal with, for they are re-
markably easily collected, and immense numbers can
be packed in very small space, and sent through the
post without harm befalling them.

As regards localities, though Coccidae are found
north and south of the fortieth parallels, yet they can-
not be looked upon as abundant. Search for them will
be best rewarded in the warmer temperate zones, and
in the tropics, where there is a vast unworked field of
investigation that would richly reward the entomo-
logist. They are found chiefly on trees and shrubs,
ferns and palms ; much collecting may be done by those
who receive plants from the tropics, and importers
have great opportunities not only for collecting these
insects, but also for preventing the introduction of
harmful species.

In collecting it is best to simply gather portions of
the host plant without disturbing the parasites, and to
get plenty of the material, and both sexes where possi-
ble. In preserving it is well to avoid alcohol, for
specimens collected in this way are often useless and
cannot even be identified ; however, it is sometimes
iiselul lor the softer species, but, as much as possible,
Coccidae should be preserved dry. Flat card boxes
serve the purpose best, though envelopes are useful ;
yet boxes have the advantage of saving any parasites
that may emerge ; a full description of locality, date,
etc., should be written on each. Tin boxes being air-
tight give rise to mould, and should therefore be
avoided. With those specimens which are too fragile
to preserve well, a rough sketch of their form should
be made. To keep permanently, place the Coccidae in
glass tubes, with cotton wool stoppers until the speci-
mens are quite dry, and then later put in india-rubber
stoppers.

To mount for the microscope, it is first necessary to
boil away all the soft parts with caustic potash, and
then mount in Canada Balsam, after the usual washing
dehydrating, and clearing procedure.

A Means of Ma^rking the Position of
Objects upon the Cover- Glass.

It is often necessary to mark upon the upper surface
of the cover-glass the position of objects mounted be-
neath it, but it is by no means easy to do so without

Nov., 1904.J

KNOWLEDGE & SCIENTIFIC NEWS.

279

some iiiL-chanical aid. I have found that the simplest,
and perhaps easiest, methcd is to carelnlly bore and
file out a sound cork, or portion of a cork, so as to fit
not too tightly over the end of the objective, leaving a
fairlv substantial margin to give comparative rigidity.
Through this margin^ is bored a small hole pointing
downwards and inwards towards the optical axis, and
holding a tine sable-brush. The marking liquid may
be Brunswick black, or asphalte thinned to a suitable
consistency with turpentine. It is then oiily necessary
to adjust the brush up or down in its obliquely-placcd
hole so as to give a ring of the requisite size, to rack
the objective down towards the cover-glass until the
brush is in contact with it, and to rotate the cork ring
which holds the brush so as to describe the necessary
circle. The rotation should be in the opposite direc-
tion to the hands of a clock so as to avoid unscrewing
the objective on the one hand, or unscrewing the front
lens on the other, and for the same reason this direction
of rotation should be adhered to in putting the cork on
to the objective or in taking it off. Too much black
must be avoided, and the brush must be very carefully
pointed, or the ring is not made neatly and satis-
factorily. .Another method is to fit a cork on to the
objective in the same way but to allow it to project
somewhat, and to press into it a small brass ring with
a carefully ground edge. This ring is painted with the
marking fluid and brought down gently upon the cover-
glass, but it is difficult to make neat rings by this
means, and to be of much use the brass ring and the
consequent hole in the end of the cork have to be much
smaller than the bore which takes the objective, so that
the cork is not easy to file out, and the projecting ring
interferes with the field of the objective with low
powers, and with the focussing with high ones.

Gla.re when using a Vertical Illunninator

Workers on metal specimens who use the vertical
illuminator are aware of the glare which is constantly
present in the field of view, and often to such ;in obtru-
sive extent as to seriously diminish sharpness of
definition and perception of detail. This is generally
due to reflections from the inside f)f the mount of the
objective. This glare may be greatly reduced — in fart,
for practical purposes, eliminated, by placing an Iris
diaphragm close to the source of light and reducing the
aperture through which the light passes, by means of
this diaphragm, to such a point as will remo\e the
objectionable glare. It will be found that this will not
affect the brilliance of the actual image, for only pre-
cisely the amount of light that can be usefully utilized,
no less and no more, will pass through the objective.
A similar arrangement in connection with ordinary
photo-micrography removes the glare which is so often
objected to, from the inside of the body of the micro-
scope.

Notes and Queries.

.1. M. [lunhar, Cast Griqualand.

Several correspondents kindly answer my query last
month by recommendin.;,' Hassairs •' Adulterations Detected "
(Longmans, I057) as a book which deals with the microscopical
examination of adulterated foods. It contains over 200 micro-
scopical illus rations. I am also referred to Rattershall's" Food
Adulteratioi.,' price J5S., wliich has photo-micrographic plates.
This last is an .American publication, but may he had in
London at Spon's.

J. CarriniSton, East London, S.A.

I would recommend you to j^et Lewis Wright's " Popular
Handbook to the Microscope" (iSijp), published by the
Religious Tract Society at 2S. Od. This is quite elementary,
and contains chapters oil some common microscopical objects.
.Mso Cross and Cole's •' Modern Microscopy" (ujc);), published
by Baillicre, Tindall, and (.'ox, at 4s. This deals most clearly
with the microscope and its use on the one hand, and with
mounting methods on the otlu'r. If yon have any special
ditVuulty I shall be glad 1" help yon with it.

J. P. Hodges, firanjietown, Yorks.

'I1i(! Ksohition oi Ainl'hipUuni j-cUmida has long been a
f.ivouvite task with amateurs, but it is really not so dillicult as
it seems. The first retinisite is to have the diatoms mounted
in a medium of suitaljlc refractive index, such as realgar,
though monobromide of naphthalin will do. The objective
should have an aperture of about 1-25 or more, and if the con-
denser is also an innnersion one the result will be the more
satisfactory. Search the slide and pick out a good diatom —
thev vary more than would be imagined. Can-fully centre
the condenser with a low power by means of tlie iris dia-
phragm, then bring the lamp-flame into the centre of
the field, using the edge of the flame and keeping
the tail-rod central. Focus the flame sharply with the
condenser. Now change the objective to the .^jth, and
without altering mirror or lamp recentre the flame and
refocus it. The transverse striations should now be seen
pretty clearly, and will not be improved by closing the
diaphragm. But if not successful proceed as follows : See
that the lamp is exactly opposite the microscope, and the
mirror adjusted so that the lamp-flame lies vertically in the
centre of the field. Adjust the slide so that the diatom also
has its long axis vertically in the centre of the field. Make
all other adjustments as before, taking pains with the centring.
Now beneath the condenser put a stop which has one
slit in it reaching from the edge to the centre, and about
^ inch wide, placing tlie stop so that the slit lies to the front of
the condenser. .\ "slight tilt of the mirror in its gymbals may
be necessary to bring the striations clearly into view, and
a little adjustment within narrow limits sometimi-s worlis
wonders, but the principle is to throw a narrow and very
oblique beam of light longitudinally down the diatom. Of
course the image does not represent the real structure of
the diatom, and that is a point which has been much dis-
cussed. The resolution of diatoms is certainly not a waste of
time ; I question if anything so soon teaches a microscopist
how to use his instrument to best advantage, or if any other
study has given as much impetus to the demand for better
objectives, better corrections, and better apertures, and so
helped to bring about the comparatively recent great advance
in this respect.

Microscopical Material.

Mr. .Mfrc'd Death, of F)Ury St. h;dmunds, has kindly sent
me for distribution a (piantity of ICchiims spines. The cutting
and rubbing them down for mounting is, as Mr. Death says,
somewhat tedious work, Init they make beautiful objects for
either directly transmitted light or annular illumination,
generally known as "dark-ground." Mr. Death gives the
following rhumc of his method of procedure: (i) Make
transverse section, as of any h.ird tissue. (2) Rub one
side quite smooth upon a hone, preferably VVater-of-Ayr
stone. (3) Fasten smooth side upon glass slip with Canada
balsam. (4) Grind section on glass upon hone until suniciently
thin. (3) Remove section from hone by warming over spirit
lamp. (Ol Fass through alcohol into clove oil and mount in
Canada balsam. I shall be pleased to send one or two of
these spicules to any reader who sends me a stamped
addressed envelope, together with the coupon appearing in
another part of this issue, and it will be a convenience to me
if applicants will enclose in the envelope a small piece of
tissue paper in which to fold the minute spicule.

[Commtintcalivns and fm/iihies mi Miii'iKwopiuil matlcn iii-d invilcJ,
and ihuitld he addressed to F. Shillingtvn Scales, ••Jersey, "St.
Barnabas Huad, Cambridge.]

28o

KNOWLEDGE & SCIENTIFIC NEWS.

[Nov., 1904.

The Face of the Sky for November.

By W. Shackleton, F.R.A.S.

The Sun. — On the ist the Sun rises at 6.55, and sets
at 4.32 ; on the 30th he rises at 7.44, and sets at 3.53.
The equation of time is a maximuni on the 3rd, the Sun
being i6m. 21s. before the clocl<.

Sunspots and prominences have been numerous of
late ; at the time of writing five groups of spots are visible.

The positions of the spots, &c., with respect to the
equator and poles may be deri\ed by employing the
following table : —

Date.

Axis inclined from N.
point.

Centre of disc, N of
Sun's equator.

Nov. I ..

II . ■

,, 21 ..

Dec. I ..

24° 39' E.
22° ii' E.
19° 41' E.
16° G' E.

4° II'
3° 6'
i°54'
o°38'

The Moon : —

Date.

Nov. 7 . .
,. 15 ••
.. 23 ••
., 30 ..

Phases.

H. M.

• New Moon

J) First Quarter

O Full Moon

d Last Ouarter

3 37 p.m.

o 36 a.m.

3 12 a.m.

7 38 a.m.

The Planets. — IVIercury is in superior conjunction
with the Sun at the beginning of the month, and towards
the end of the month he becomes an evening star,
setting about an hour after the Sun.

Venus is an evening star setting about 5.45 p m. on the
1st, and about 6.15 p.m. on the 30th. Towards the end
of the month the planet will be observable after sunset,
but low down in the S.W. The disc is gibbous, and has
an apparent diameter of i3"'o.

Mars is a morning star situated on the confines of
Leo and \'irgo, rising at 2 a.m. on the 15th.

Jupiter is in an extremely favourable position for
observation, and is the most conspicuous object in the
evening sky looking S.E., being visible from sunset until
early morning.

The equatorial diameter of the planet on the ist is
5o"-o, whilst the polar diameter is 3"-2 smaller.

At II p.m. on the 19th the planet is in pro.\imity to
the Moon, being only i"i to the North.

The configurations of the satellites, as seen in an in-
verting telescope at 10 p.m., are as follows: —

Day.

West.

East.

Day.

West. East.

21O43

2O134

2O413

13O24

43I02

3O124

4302

3241 0

432U1

432 0

413O2

40152

4U123

412O3

4i03

42O13

-t

413O2

^i02

43O12

30I4

3421O

0 3204

3240

• »s^

O1324

OI234

I ©34

I2034

2O134

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

Saturn is on the meridian about i i hours after sunset ;
hence this is the best time for making observations ; the
brightness of the planet is diminishing in consequence of
increasing distance from the earth.

The ring appears widely open and we are looking
clown on the northern surface at an angle of 16°; on the
5th the polar diameter of the ball is i3"'6, whilst the
major and minor axes of the outer ring are39"-4 and ii"-o
respectively.

The planet is in (juadrature with the Sun on the 7th.

The moon is near the planet on the evening of the 14th.

Uranus is unobservable, setting shortly after sunset.

Neptune rises about 11 p.m. near the middle of tlie
month ; his position in the constellation Gemini will be
seen on reference to the chart appearing in the January
number.

Meteors : —

The principal showers of meteors during the month are
the Leonids and Andromedids. Watch should be kept
for Leonids after midnight of the 14th and 15th, when the
moon will have set.

Radiant.

Date.

Characteristics.

R.A.

Dec.

Nov. 14-16

150°

+ 22°

Swift, streaks.

(Great Leonid

shower.)

Nov. 17-23

25°

+ 43°

Very slow ; trains.

(Great Adromedid

shower.)

Encke's Comet : —

The re-discovery of Encke's comet by photography
with 3^ hours exposure at the Kiinigstuhl Observatory
has been confirmed by a later photograph taken at the
same place, which establishes its identity beyond doubt.
The comet is described as extremely faint and diffuse.
Its approximate position on November i is R..\. 23 hr.
17 ni., Dec. -j- 26° 5]', or a little east of 1^ Pegasi ; it is
moving in a direction W. by S.

The Stars : —

About g p.m , at the middle of the month, the following
constellations may be observed: —
Zenith . Cassiopeia.
South . Andromeda, Pisces Cetus; Pegasus,

Aquarius towards S.W.
West . .Vijuila, Cygnus, Lyra a little north of

west, Corona N.W. setting.
East . Auriga, Perseus, Pleiades, Taurus ; Aries

to the S.E. ; Orion rising S.E.
North . Ursa Major, Ursa Minor, Cepheus;

Draco a little west of north.
Minima of Algol will occur on the .Sth at 1 1 .50 p.m., on
the nth at S.39 p.m., and on the 14th at 5.28 p.m.

Telescotic Objects: —

Double Stars : — v Cassiopeise o'' 43™, N. 57° 17',
mags. 3J, yh ; separation 5"-7. Binary star.

X Arietis i'' 52"^, N. 23°-6', mags. 4, 8; separation 37".
Components white and blue ; easy with power 20.
Persei 2^ 44'", N. 55°-28' ; mags. 4,

separation
28". The brighter component is orange, the other blue.
There are also several other fainter stars very near.

KDouiledge & Seieotilie Ileuis

A MONTHLY JOURNAL OF SCIENCE.

Conducted by MAJOR B. BADEN-POWELL and E. S. GREW, M.A.

Vol. I. No. ii. [new series.] DECEMBER, 1904.

[Entered at n
Stationers' Hall.J

SIXPENCE.

CONTENTS.-See Page IX.

The ConservQLtion of
Mass.

By Alikeu W". Porter,

Fellow of, and Assistant Professor of Physics in, University
College, London.

The principle which is the basis of all analytical
chemistry is expressed by saying that whatever com-
binations or separations are effected in different
materials the total amount of material present remains
constant. The amount of material referred to in this
statement is not measured by its volume ; indeed, in
many cases, this imdergoes considerable change. The
measurement is made by a balance, and the actual
process of measurement consists in counterpoising the
substances under examination — both in the free and
combined states — against given " weights "; the
" weight " so obtained is then taken as being a measure
of the quantity of material present.

We are not now concerned with the illustration of
this very familiar principle, nor with the question of
its practical truth, which is undoubted. Every chemist
trusts in its truth when he expects the results of his
analysis to add up to 100 per cent. But as considerable
interest is to-day felt in the possibility that the law is
not completely satisfied, we intend to examine as simply
as possible the experimental means by which its failure
might be ascertained.

However, in the first place, it is important to have
clear ideas as to what the problem really is. Some
confusion of thought about it is prevalent. This con-
fusion arises from the current confounding of mass
and weight. Can we take the weight of a body as
being proportional to the quantity of material in it?
My housekeeper tells me it is so. Two pounds of
sugar weigh twice as much as one, and there is twice
as much sugar in them. Unquestionably .so — from )ier
point of view; but we must look at things a little more
accurately than my housekeeper docs.

When any material is placed in one pan of a balance
it presses on it with a certain force. This force is said
to be " due to gravity " — a statement, however, which
does not add much to our knowledge. It would be
much more explicit to say it is due to the earth; for
there is every reason to believe that if the earth were to
disappear the force would vanish too. It is this force
w-hich is scientifically defined as being the weight of the

body. \ow if anything has been proved with certainty,
it is that the weight of a body is not always the same.
Hang it on a spiral balance; the extension of the spiral
spring is less if the experiment is made near the
i-quator than near the poles. Or, better still (for a
spiral spring is not very sensitve), place the body on
one of the extremely ingenious spring balances which
have been recently devised, and which consist simply
of a horizontal fibre of quartz supported at one end — a
cantilever, in fact. These are of wonderful sensitive-
ness and constancy also; the same force at the free end
produces the same amount of bending every time.
But a given fragment of material placed on it will pro-
duce a different deflection near the earth's equator than
if the experiment is made near the earth's poles. It
will be different if the apparatus is high up a mountain
than at the sea-level. There is no constancy of weight
c\en for the same body in the same state; this is
acknowledged by all. .So that, after all, it cannot be
the weight that is being taken as a measure of the
amount of material when the principle of the conserva-
tion of material is asserted to be true. The confusion
arises from a peculiarity of the ordinary hal;mce. The
material is placed in one scale pan iqjon which it
presses down. Weights (i.e., st.andard blocks of
material) are placed in the second pan, upon which
they press down. If the two just counterbalance one
another, and if the balance is accurate, they are said to
be equal to one another. The comparison made here is
between the turning power of two weights, and if the
arms of the balance are of the same length, equality
of turning power involves equality of the weights them-
selves. l-!\en in the most accurate analyses, then,
although it is the iveighis of the constituents of any
body which are currently taken as being e(|ual in the
aggregate to the total weight of the body they com-
[lose, yet it must not be forgotten th.it .ill the weighings
• iri' made in the same locality.

.Suppose now that the constituents are weighed on a
sufficiently sensitive spring balance, and that some of
them are weighed near the equator and some near the
polar regions. If what we have said above about the
\ariation of weight with positions on the earth is true,
the sum of the separate weights will not equal the
weight of the compound or mixture. The total weight
of a body is admittedly not conserved, but depends
iijjon the conditions under which it is w-eighed.

This variation canr.ot, however, be detected by an
ordinary balance. Tw'o weights that counterbalance
at one part of the earth will balance everywhere else;
in other words, though the pull of the earth on each
undergoes variation, it varies in the same proportion
for each; and, consequently, if they are equal anywhere,
the equality is universal. It is this peculiarity of an
ordinary balance which has led to the popular notion

282

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

that the amount of material in a body can be measured
by its iccighi. If any other kind of sensitive balance
had been employed it would soon have been realised
that this is not legitimate unless it be assumed that
the quantity of material in a body varies according to
the part of the earth on which it happens to be placed.

If weight, then, is not a satisfactory measure of the
quantity of matter in a body, can we find any property
that is?

If we were concerned only witli matter of the same
chemical kind — for example, iron — and exactly the
same in all respects except that there was a bigger
volume of one than of the other, nobody would hesitate
to measure the quantity by volume. Matter would be
bought by the cubic centimetre, or cubic foot, or the
quart. Two quarts would always represent twice as
much matter as one. But the world is " full of a
number of things," and it is not easy to explain exactly
what you mean if you say that there is as much material
in a certain volume of water as in a certain block of
lead. What is the criterion of equality in such a case as
this when the material is of different kinds? In com-
merce, a certain volume of iron is given in exchange for
a much smaller volume of gold. In some sense, then,
these different volumes are taken as being a measure
of equivalent quantities of the two materials; and if a
fixed relation were preserved between these quantities,
a perfectly sound scientific system could be founded on
such a basis of equivalence. But familiarity with
market fluctuations would soon breed contempt for
such a system; it would be absolutely of no use for
scientific purposes. It has been agreed to measure
quantity of material not in the commercial way ; not
even by its weight, which is nearly satisfactory ; but by
another dynamical way, which, at any rate, till re-
cently, was thought to make the principle of the con-
servation of material precisely true under whatever
circumstances the quantity of matter is measured.

We will explain this method.

When Sir Isaac Newton thought out his Laws of
Motion, he percei\ed that every change of motion is
brought about by the influence of one body upon
another, and, moreover, that this influence is a mutual
one. When two billiard balls strike, the velocity of
both is changed; each influences the motion of the other.
A horse gives motion to a cart, but the cart simul-
taneously retards the motion of the horse. The main
part of the motion of the moon is controlled by the
influence of the earth, and reciprocally the moon modi-
fies the motion of the earth.

Think now only of the simplest possible case, viz.,
that in which the mutually influencing bodies move
along the same straight line; two billiard balls, for
example, moving without spin. When they strike, the
speed of one is increased and that of the other is then
always retarded. Measure, or (since this is not always
easy to dp, and we do not wish to introduce here the
complications of actual measurements) imagine
measured, the change of velocity of each. The ratio of
the changes, _,so far as all experiment has succeeded
in obtaining it, is_ the same for the same two bodies
whatever the previous velocities may have been. For
two billiard balls it would usually come out as
numerically equal to unity; whenever it does so the
masses of the miJucimng bodies are defined as being
equal. If the ratio of the changes of velocity is not
unity, the ratio of the masses of the tivo bodies is defined
as being inversely as the ratio of the changes of velocities,
whatever it may be. For example, if the balls be called A
and B, and A increase its velocity (due to the influence

of B) from 4 to 10 units, while B diminish its velocity
(due to the influence of A) from 6 to 2 units, we have
Increase of velocity of A 6 _ Mass of B.

Decrease ot velocity of 13 4 Mass of A.

Hence in this hypothetical case B has ih times the mass
of A, and no matter what the circumstances of the
influence may be, this relation is found to be constant
for the same two bodies A and B; for example, if A's
velocity increase by 12 units due to B, then B's will
decrease 8 units due to A. The more massive body
has its velocity changed to the less degree; hence, mass,
as we have defined it, is a measure of the reluctance of
the body to be disturbed. A fly alighting on a cannon
ball scarcely affects the motion of the latter; a cannon
ball striking a fly sweeps it apparently irresistibly
before it. In each case the motion of the ball is
changed but little because its mass is so enormous in
comparison with that of the fly.

The supposed constancy of the mass of a body under
every condition makes the mass an eminently suitable
means of measuring the quantity of material in it, and
is universally adopted as such. Thus, in the example
given above, B is said to contain i\ times as much
matter as A. This mode of measuring matter corre-
sponds to considering the quantities equal when the
same kind of substance is present m equal volumes;
but for different kinds of substances the quantities may
be equal when the volumes are very different. A cubic
foot of lead has about 11.35 times as much matter or
mass in it as a cubic foot of water.

In a later number we will show the relation between
mass and weight, and we will then be in a position to
explain the nature of the evidence that has in recent
years been brought forward in the endeavour to prove
that the principle of conservation is not precisely true.

The Radio-activity of
CKemical Reactions.

By A. F. Burgess .AM) B. Ingram, B.A., F.C.S.

It is, ol ctnu'se, a well-known fact that e\ery chemical
reaction is attended by the evolution or absorption of
energy in some form or another. That a chemical
equation does not adequately represent a chemical re-
action has recently been further attested by the work
of Colson, who has found that when a supersaturated
solution of sodium sulphate is made to crystallize it
gives out n,-rays. A mixture of aluminium, sulphate,
and potassium sulphate does not give out Uj-rays until
crystallization [i.e., with formation of alum) is started.

Much interesting research has been done on this sub-
ject, and the more substantial proof has been supplied
by Landolt and Heydweiler, who have succeeded by
means of a balance of high precision in detecting
losses in chemical reactions by radio-activity. In fact,
the discrepancies, which Stas constantly encountered
in his weighings when engaged in his classical research
on the "Indestructibility of Matter," may now be
satisfactorily accounted for on the proof that, in chemi-
cal processes, the loss is due to certain emanations.

Our first experiment (which was entirely specula-
tive) consisted of placing in a light-tight box the

Dec, 1904.1

KNOWLEDGE & SCIENTIFIC NEWS.

283

lollDwiiiy sul)st;inccs ananyccl in ihc posilii)iis as
shown in the diagram. These were coveicd by a sheet

Our lirsl experiment willi the /iiir-coppci- ci uple
beneath llie support C proihiccd llie aici>ii\p:mvini; re-
sult (see V'lg. J,], 'llie exposure lasted <le\iii days

.^-^

Wax.

Amalgam.

Match.

^CL

of ordinary note-paper, and on the top was placed
(film downwards) a photographic plate. We left it
from July 28 until .September 6 (40 davs).

Fig. 1.— July zS-Sept. 6, 1004. 40 days.

It will be observed that the general illuniinatiui:
comes from the centre of the plate directly over the
sodium amalgam into which water had been allowed to
trickle. The obstacles were pieces of plain and per-
forated zinc, copper, and tinned iron. In order to
investigate the cause of this action we exposed our
materials for a period of twenty-one days to the radio-
acti\e effects of gas mantles, and then tried their
effect, as before, for ten days (.September 6 to .Septem-
ber 16). When the plate was developed it appeared
quite clear. Incidentally we observed that unused gas
mantles have precisely the same effect as the used gas
mantles.

Our next experiments were conducted in an iron
box, blackened and made thoroughly light-tight. A
section through the apparatus is given in I'ig. 2.

A, vessels containing chemical reagents.

B, wool connecting them.

C, iron support.

D, note-paper.

E, obstacles.

F, plate (protected) with film downwards.

G, thick sheets of red paper.

Fig. .?.- Sept. 20-Oct. I. 1004.

days. Cii Zn in Sulphitric Acid.

(September 20-October i). Hotli the pieces ul zinc
have become sources of light, llins [)ro<lucing an effect
entirely different from our other results.

It may be stated here that the pieces of zinc used had
not been in use before for any previous experiments.
After an exposure of thirteen days phosphorus in water
gave no result whatever. Our next plate is the result

Fig. 4. Sept. 2.i-0ct. 3, iyo4, loday.'i. Ammonia and llydrocliloric
Acid ifuminKi.

of exposure to fuming ammonia ;in(l hydrochloric acid.
In s[Mte of our precaulioiis to the contr.iry the liquid
managed to crawl up to the plate and affect it as
shown above.

It then occurred to us to try the elfect of a double
reaction, such as takes place when calcium carbide is
treated with water.

(i) CaC, + H.,0 = CaO + C,H,
(2) CaO 4- H.O ^ Ca(() II),

After an exposure of only two days tin- plate was
developed with the accompanying result. The light
[)ortion was the part immediatelv over the vessel con-
taining the calcium carbide. i'he lines were on the

284

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

paper in which the photographic plate had been
wrapped. Another piece of perforated zinc served as
the obstacle. It can be faintly .seen with the shadow- of
the iron support running across it almost parallel to
the edge of the print.

We next tried the effect of rapidly evaporating some
ether in our apparatus. We used a piece of bromide

Fig. 5- Oct. 8=10.1004. 2 days. Calcium Carbide and Water.
Obstacles : Zinc tone piece plain, one perforated).

paper, carefully protected* from actual contact with
the vapour, and placing a penny as the obstacle, we
endeavoured to obtain an " instantaneous " photo-
graph by a three-hours' exposure.

Fig. 7 shows most clearly the effect of a chemical
reaction. Here the piece of perforated zinc can be

Fig. 6.— Oct. 4, 1904. Exposed for three hours to ether vapour.
Obstacle : Penny.

plainly distinguished ihrougli the iron arm of the sup-
port. The obstacle on the right is a plain piece of zinc.
The plate is the result of the slow decomposition of
hydrogen peroxide, H.jO., — Il,(_) 4- O, lasting over
a period of thirteen days.

Our last effort was to expose a plate to some euca-
lyptus oil for a period of thirteen days.

We are not aware that any chemical change goes
on when this oil is left alone, nor could it have evapor-

Fig. 7.-0ct. 8.21, 1904. 13 days. HoOj.

atcd to any extent, seeing that the box was closed the
whole time; vet the plate shows some action of some

* Ether blackens bromide paper on development.

Oct. N = 2i, 1904. 13 dayj. l;iEcaljptus oil.

kind, and we leave it to the efforts of the readers of
" Knowledge " to suggest a satisfactory explanation.

Note. — Will Mr. A. F. Burgess communicate his address to
the Editor.

Spectrum Analysis. — It is not quite easy to classify "-An In-
troduction to Spectrum Analysis" (Longmans. Green), by Dr.
Marshall Watts, which is something between a textbook and a
work of reference. Perhaps its best title is the one that has
been found for it ; and it may be confidently recommended to
students who wish to take up the study of spectroscopic
methods from the beginning. It is divided into two portions ;
the first of which describes spectroscopic work and discusses
the uses of instruments ; the Fraunhofer lines of the solar spec-
trum, the meanings and implications of the " Zeeman Effect,"
and of obser\ations in stellar spectroscopy generally ; the
Michelson echelon diffraction grating; and the work of Pro-
fessor Hale with the spectro-heliograph. The second part of
the book embraces some hundred and eighty pages of cata-
logue of spectra.

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

285

The VitoLl Eacrth.

By Gkenvii.i.e A. J. Cole.

The .-' wness of the processes of mountain-building
and denudation, the coldness of common rock, and the
manifold signs of activity, on the other hand, in the
organic kingdoms, have conspired to make us regard
our planet as a dead mass, the destiny of which is now
concentrated in that of the human race.

There is no doubt that man and his movements
have the supremest interest for ourselves. Ethno-
graphers have discussed the influence of environment,
and have seen the geographic cradle, as it were, re-
flected in the characters of a tribe. But, again and
again, the migrations of peoples, with customs and
manners ready formed, have shown us that man may
finally impress himself on his new surroundings, in-
stead of being forced into their mould. Our pre\alcnt
classical education, moreover, ignoring natural pheno-
mena on the one hand, and the long struggks of
prehistoric man upon the other, tends further to fix
our attention on the dominant position that we have
attained.

But is the earth on which we move so very lifeless
after all? If we construct a diagram to show how
much of this ball, 8,000 miles across, is accessible to
our direct enquiries, we are at once brought face to
face with the enormous possibilities of the interior.
We are familiar with the circulation of water, for
example, between the atmosphere and the uppermost
and disintegrated layers of our rocks; but we may well
ask if all the water, and all the gases, were success-
fully extruded at the period of the consolidation of the
crust. This period, again, is still in progress; the
crust is far from stable, and grows by additions from
below. Substances, till now occluded, may be given
out, when passage is afforded to them during the
movements of the upper layers; others may become
incorporated in the crust, and may ultimately be
brought within our reach, in their Liter modifications,
upon the surface.

Prof. Suess, of \'ienna, has recently pressed home
upon us the distinction between permeating superficial
fluids, as defined by Posepny, and those that are in
reality nascent and come to us from below. We still
meet in newspapers, and in many scientific text-books,
the theory that the waters of volcanoes originate from
inroads of the sea; and the influence exercised bv this
view is emphasised by the clearness with which Prof.
Suess has found it even now necessary to stand out
against it. " The steam of volcanoes," he says,*
" cannot arise from infiltration from the surface, and
such infiltration is clearly out of the question in the
ca.se of the carbon dioxide. Whence, then, do these
substances arise? They proceed from the deeper inner
regions of the globe, and are the outward signs of that
loss of gases, which began with the first consolidation,
and which is not completely over, though localised at
certain points and lines. In this way the oceans and
the whole superficial (-.'adose) hydrosphere became
separated from the body of the globe. \'olcanoes are
not fed by infiltrations from the sea, but the seas in-
crease in volume as the result of each eruption."

• " Ueber heisse Quellen," Address to the Society of German
Naturalists and Doctors at Karlsbad, 1902 (Prometheus. XIV ,
1903, p. 226).

Suess points out that this proposition is not new;
yet it needs repeated allirmalion. I'rom some points
of view, in fact, the interior of the earth, with its
concentrated metals under high temperatures and
pressures, is still young and potent, a planet still
capable of giying off light-rays of its own, were its
stony envelope removed. The incandescent glow of
the material ejected from volcanoes brings us, as
Tschcrmak has indicated, near to the cosmic forces
that are common to the systems of the stars. The
liberation of gases and " emanations " in the past is
no real measure of what remains occluded in our own
(lav. Combinations, moreover, may be possible at the
existing high temperatures in the interior, which lower
temperature and relief from pressure may in time con-
vert into other and even st.irtling forms.

The object of the present paper is to ask for a
suspension of judgment in regard to several questions
which geological instructors are apt to pass over as
well proven. A wise review of this matter appears in
the last edition of Sir A. Geikie's " Text-book of Geo-
logy " (1903, pp. 351-8), where many useful refer-
ences to published papers will be found. We gain
new interest in the water that permeates volcanic rocks
from the amazing eruptions of Martinique and .Saint
\incent in IQ02. The stories of poisonous gases and
fiery exhalations soon gave way before scientific
examination; the burning and scorching effects proved
to be due to hot volc.inic dust, sent forth in such
(|uantitics as to practically exclude the common air.
No n.ime or ordinary combustion was possible until
the dust-cloud relaxed its first closeness and intensity.
Moreover, its very texture and continuity seem to have
been due to the evolution of water-\apour from each of
the myriad particles that were ejected simultaneously
from the vent. But it is difficult in such catastrophic
examples to realise what is actually going on, and what
gases are being liberated so abruptly from the parent
earth. The study of the vapour-jets and hot springs
that remairi in volcanic areas for centuries after activity
in the ordinary sense h;is passed away, has gi\en us
an impressive picture of the immense streams of matter
passing from the inner rocks into the hydrosphere.
The prevalence of carbon dioxide is especially striking.
N'ot only at the famous fJrotto del Cane near .\aples,
but at the far more accessible Grotte du Chicn at
Royat in the Department of the Puy-de-D6me, we
may become immersed in a bath of this dense gas as
it oozes from the pores of solidified volcanic ground.
The opening of a bottle of natural mineral water,
though the " sparkle " in different species occurs in
\ery different degrees, brings us into touch in a more
homely way with the unexhausted vitality of the earth.
Probably no one attributes the carbon of the gaseous
compound thus brought to the surface to the decay of
ancient vegetation within the crust, ^'et the case of
petroleum is probably similar; and here the material is
generally referred to as of an organic origin. A com-
bustible material, however strange its mode of oc-
currence and emanation, seems to suggest from the out-
set fossil forests and old swamps, and it is almost im-
possible to persuade " practical men " that carbon
exists in the earth apart from coal-seams. The very
fact that petroleum is in some cases successfully dis-
tillefl from Carboniferous shales is, moreover,
commonly held to prove its organic origin in all areas.
C'arbon and carl)on-<:ompounds, liowe\er, must have
existed on our globe long before living things arose
upon the surface, and it is no mere speculation to
suppose that much of the material remained unavail-

286

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

able on account of its combination with metals in the
hidden depths.

The occurrence of graphite offers many interesting
suggestions. In Siberia and in the Western Alps, beds
(if graphite may be traced into strata that retain
recognisable vegetable I'eniains. V\'einschenk ■ , who
has "given special :ittention to this matter in recent
years, believes that the graphitic anthracite of the
Alps — which one may see, for example, collected for
fuel on the summit of the Little St. Bernard — passes
into graphite as the result of the intrusion of the ad-
jacent granite. In the .-\rch;can region, however, of
the frontier of Bavaria and Bohemia, Weinschenkj
finds no sign of an organic origin for the beds and
lens-like masses associated with the ancient gneiss.
He urges that the graphite is here deposited from gase-
ous exhalations, whicli were connected with the inflow
of granite in the area. CirLuier's experiments on carbon
monoxide in 1869 lead \\'einschenk to reg;ird this gas
as a very probable source of carbon in the gneisses.
It appears that iron f)rcs at 300° C. decompose carbon
monoxide with deposition of graphite; the little known
metallic carbonyls, moreover, may also be looked to as
furnishing carbon in a volatile foi'm. Such substances,
with carbon dioxide and water, are pictured as
saturating the rocks in contact with the invading mass,
and as taking advantage of any planes of easy penetra-
tion, during the folding of the ancient series. Mica-
schists, with the easy partings offered by the prevalent
mineral, might thus become impregnated in a special
degree; while cavities provided by earth-movements
would ser\ e as chambers of deposition. As years go
on, we shall probably learn more and more of the pro-
ducts vet to emerge from the earth's unknown interior.
While we are on the verge of gaining some ideas on
elemental transmutation, we may e\'en look forward to
the exhalation in due time of substances imknown to us
in our present geological age. Time may be an im-
portant factor in the internal processes of our vital
globe; and who shall say that senility has yet set in?
Is it not at least a fair speculation that life itself m;iy
be a phenomenon expressing a particular phase in the
history of our globe? Life may not be a merelv
external reaction, limited by temperatiu-e, and con-
trolled by cosmic law upon a cooling and indifferent
planet. May w'e not in time see some return towards
the conception of the grc.it Karlh-mother, fostering
her children from within, stimulating them daily
against attack, revi\ing them, perhaps, in hours fif
danger, and fitting them to cope with future changes
bv changes in her own heart's core?

" .Mihandlunfjen der k. baver Akademie der Wiereneclmftf n
II. CI, XXI. Band, irjno.

I IhiJ , XIX Bnnd, i:-'.,;.

AwaLrds to the Wellcome Chemical
' [Research Laboratories, London.

TuK Committee on .Awards of the Loufsiana Purchase Exposi-
tion, St. Loui?. have conferred upon the Wellcome Chemical
Research Laboratories the distinction of a grand prize and
three gold medals, in recognition of the importance and educa-
tional value of the chemical and phannacoKnostical researches
conducted in these lal)oratories under the direction of Dr.
Frederick B. Power.

PKotogroLphy.

Pure and Applied.

By Ch.M'.m.w Jones, F.I.C, F.CS., &c.

Koii/g's Thrce-Colpw Process. — This process, only re-
cently published, has attracted a good deal of attention,
and deservedly so, for it not only illustrates a new
principle as applied to the purpose of colour photo-
graphy, but has been worked out by its author to a
successful issue. Whether or not it will be found to
fulfil the conditions necessary to establish itself as a
standard or commercial process, only time can prove.
It is a triple film method, Isut differs from those previ-
ously proposed, in that each colour is printed out by
light.

Many of the organic dye-stuffs yield on reduction
colourless or leuco-derivatives, which can be oxidized
to reproduce the original colour with more or less
facility, and expf)sure to light generally facilitates
this oxidation. By choosing a dye of a suitable colour,
and one that yields a leuco-derivative of sufiicient
stability to withstand the necessary operations and yet
is sensitive enough for practical printing- purposes, it
is obvious that the colour may be obtained directly by
exposure to light under the negative, and the necessity
for a relief produced by the chromated gelatine process,
or any similar indirect method of getting the required
distribution of the colour, is obviated.

These leuco-derivatives were found to be useless by
themselves or in an inert film, as they then gave only
poor and flat images, but the presence of a nitric acid
ester was discovered to overcome this difficulty.
Pyroxylin being an ester of nitric acid a collodion film
is employed, and mannite nitrate is very suit.able for
further augmenting the sensitiveness. The removal of
the excess of the leuco-derivative after exposure was
at first a difficulty, as ordinary solvents and acids were
found useless for the purpose. But monochloracetic
acid is effective, and it is used as a ten per cent, solu-
tion.

The process consists in coating a suitably surfaced
paper with a one-and-a-half per cent, collodion, to
which the leuco-derivative and other desirable materials
have been added, exposing under the appropriate nega-
tive until the colour is sufficiently intense, fixing in the
chloracetic ,-uid solution, washing, and dipping into a
gelatine solution that contains chrome alum and dry-
ing. The print is again dipped into the gelatine solu-
tion and dried to effectively protect the collodion film
during the application of the collodion th;it is to
furnish the second colour. This routine is repeated for
the second colour .and again for the third, and the print
is finally varnished.

The method of judging when each colour is correctly
printed is not very clear, as it seems impossible to
adjust the depth of tint of the films that are sealed up
by the subsequent coatings. The process is apparently
rather tedious, as there are three collodion films, six
gelatine coatings, and a final coating of varnish to dry.
The obvious objection to the number of films because
of their combined thickness is probably invalid, as the
collodion and the gelatine solution used are weak and
the films they give correspondingly thin. ,\ real diffi-
culty I should have expected to be due to the action of
the chloracetic acid on the gelatine films under the
collodion film that is being subjected to the fixing

r)?c . 1904.1

KNOWLEDGE iS: SCIENTIFIC NEWS.

2<S7

I'jK i ..ii,.ii, lui ^Iculnlcss this possibility has received
attention.

Liimierc's Siar:li McthoJ of Tlircc-Coloiir Fliolograpliy.
— This process, which was described about six months
ago, contrasts \cry emphatically with Konij^'s method
in the simplicity of the necessary manipulation. NO
colour screens or filters are needed, there arc no films
to stain, no colours to produce of the correct intensity
to match one another, no separate nesjatives \\ ith sub-
sequent printinsjs, but merely one exposure, ordinary
development, and then, instead of fixint;, the silver
image is dissolved out and the remaining siKer salt
reduced to the metallic state. Rut if the work of the
photographer himself is simple, it is because of the
complex character of the prepared plate, and pre-
sumably it is the difficulties of manufacture that have
led to the delay in putting the prepared plates on the
market. The plates are made by selecting starch
granules of from 15 to 20 thousandths of a millimetre
in diameter, staining quantities of them red, green, and
violet respectivelv, dr\ing them, mixing them so that
neither colour predominates but that the whole pre-
sents a neutral gray tint, and spreading the mixture on
glass one layer thick. The interstices are filled in with
a fine black powder, and the layer is fixed and pro-
tected by a coat of varnish. On this is put a film of
suitably colour-sensitized emulsion. Exposure is gi\ en
through the glass, and the subsequent treatment of
the plate is as described above. The dyed starch
granules form an irregularly grained three-colour
screen, which ser\es the double purpose of taking antl
viewing.

It is easy to describe such a process, Jjut besides the
obvious mechanical difficulty of prepiiring the plates,
there must be many compromises made before the re-
sult can be passablv satisfactory. The best three
colours for the exposure are not the best three for
viewing the picture, but in this case they have to be
the same. If the stained starch granules are mixed
to the most neutral tint possible, it appears that a
perfectly orthochromatised sensiti\e film would be
necessary. The imperfections of the film in this
matter must be neutralised as far as possible. Indeed,
the difficulties of which the photographer is relieved
have to be overcome by the manufacturer, and in this
particular case they are so many and complex that if
it had not been stated that results have been obtained
in the manner described, we might \erv well doubt tin-
possibility of it.

Lantern Demonstrations. — Optical lanterns are so often
unskilfully used, even on occasions when the best
methods of demonstration might well be expected, and
.sometimes when they are handsomely paid for, that I
wish to take the present opportunity of calling atten-
tion to one matter now, and shall refer to other matters
at a subsequent dale. .\t scientific lectures it is often
necessary to introduce a small piece of apparatus on to
the stage of the lantern, such as an electroscope or
thermometer, for example, in order that its changes
during an experiment may be clearly seen by the audi-
ence. The lecturer must have ready access to the
lantern to superintend or conduct the experiment.
When there is no special provision for such demonstra-
tions, the usual way is to fix up a sheet at the back of
the platform, and to have the lantern at one side near
the front of it. The lantern has to be tipped up to get
the image above the level of the lecture table, its stage
therefore, is sloping, and apparatus put on it is very
likely to shift its position, if not to fall over; the
lecturer when at the lantern is sure to be between the

sheet and some ol tin- autlience, how L'ver he may contort
his body to get it out of the wa\; and as the lantern
is tipped up, and generally to one side of the sheet, the
disc of light is far from circular, antl it is impossible
to focus more than a small p.iit of the nbjccl, even
when it is fiat, at any oni' lime. All llusi' and other
.innovances m;iy be oxercome by the use of a small
translucent screen on the lecture-table with the l;nilern
centrallv placed behind it so as to gi\e a two or three
foot disc, taking care that the lantern is [)ro|)erly pro-
tected bv screens to avoid the possibility of .anv light
that inav leak out from it glaring into the eves of the
audience. The lectmcr would find this arrangcnu-nt
much more conxcnient, .and the audience wotdd sc;' the
projected ima^ge much more clearK-, the l.ict that It
would be smaller than olhciwisc usual liciiig an un-
qualified advantage.

Phoebe, Satvxrrv's Ninth
Satellite.

Hv A. C. I). ('K().\nn I i\.

Tiil-KK is no question that the disi-overy of I'hoebe
reflects the greatest credit on Prof. W. 11. Pickering.
It was no mere accident, but the result of a (U-liberate
sL-arch for additional satellites which he has been
carrying on for manv years, h'ven after the existence
of the satellite is known it is :i tedious matter to
identify it on a photograph, but to lia\e disc-overed it
in this way — one little grev dot among myriads of
others — is, indeed, astonishing. I'rof. Pickering ex-
plains the long delay in the contirniation of the origin.il
announcement by the fact that his attention was called
oft by his photographic work on the moon. In .iddi-
tion to this the unexpectedly large eccentricity of tlu-
orbit {q.12, foiu' times that of our moon) made it iiuiih
more difficult to detect Phoebe on the [jiates taken at
.\requipa in 1900.

.At length the idea occurred to him to extend the
search to a greater distance from .Satiun than he had
hitherto thought sufTicient, and thert% in fact, I'hoebe
was found, near elong.ation, some ^^t' from its
primary, indicatini; a dislance vA nine millions of miles.

It v\as not till a few months ago that the most
surprising leature of all — the retro<;rade motion round
.Saturn — was (lisco\ ered.

It is well known that in doubl • star orbits it is fre-
quently impossible to say whether the upper or the
lower half of the orbit is nearer to us ; in the case of
some bright stars, like .Sirius or a Centauri, the
spectroscope has settled the matter, but in other cases
it remains insoluble. In the same way we could not
tell from a single year's observations of Phoebe whether
its motion was direct or retrograde, and it was e\en
found possible to construct ;i direct orbit which would
represent the observations of 1898 .and igoo without
any large errors. Hut in 1904 the position of Saturn
has ch.anged so much that the direct and retrograde
orbits are at once distinguishable, just as the question
v\ould be settled in the case of a double star il ue
could transport ourselves to ;i \ery distant standpoint,
where we might view the system in another direction;
and it is to be noted that the retrograde motion is
indicated in two entirely different ways : (i), by com-
paring the position of the Perisaturnium, f)r nearest

288

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

point of the orbit to Saturn, in the different years ;
(2), by lea\ing the eccentricity out of account and
simply considering the change of tilt of the apparent
orbit, treated as a circle. Prof. Pickering deduced it
by method (i), and I got the same result from method
(2), being obliged to treat the orbit as circular since I
had not enough material to determine the eccentricity.

The fact that (i) and (2) are in complete accord
establishes the retrograde motion beyond reasonable
doubt, and renders highly improbable the suggestion
made by Mr. Monck and others that the satellite ob-
served in 1904 is a different body from that observed
in 1898 and 1900, both moving in direct orbits. For it
would be a most astonishing coincidence that two
independent satellites moving in direct orbits should be
so related that a single retrograde orbit of large
eccentricity should be capable of exactly simulating
the movements of both.

The retrograde motion is still further confirmed by
the fact that the observations indicate that the node
of the orbit advances (about 3° per annum), since the
node moves in the opposite direction to the revolving
body.

The sidereal period of Phoebe is 547 days, or exactly
i^ years ; the period from " New " to " New " is
about 26 days shorter, or 521 days ; this is also the
average period between successive inferior conjunctions
as seen from the earth. Thus is it alternately east and
west of Saturn, for about 260 days in each position ;
while its maximum elongation considerably exceeds
half a degree, as compared with 10 '.4 for Japetus,
II '.3 for Jupiter's satellite IV., the two greatest
elongations of satellites previously known. The mean
distance of Phoebe from Saturn is exactly eight millions
of miles, while the greatest and least distances are
9j and 6] millions. The inclination of its orbit to that
of Saturn is about 5°.

Even as seen from Saturn, Phoebe would only ap-
pear like a tiny star of the fifth or sixth magnitude ;
so that it might remain undiscovered for ages by
imaginary .Saturnians, just as Uranus, although faintly
visible to the naked eye, was not discovered till 1781.

Its diameter is estimated to be somewhere about
150 miles, slightly greater than that of Jupiter's
satellite V. The two satellites, though similar in size,
present a startling contrast in their motions; Y. is
remarkable for its proximity to Jupiter and its short
period of 12 hours; also for the very rapid motion of
the perijove, which makes two entire revolutions in a
year; this arises from the action of Jupiter's equatorial
protuberance. In Phoebe's case the perturbations pro-
duced by Saturn's oblateness and by the other satellites
must be insignificant. The solar perturbations, how-
ever, assume an importance which they do not possess
in the case of any other satellite except our moon.
Prof._ N'ewcomb estimates that the coefficient of the
cvection is about 40, three times the amount for our
moon; this will shift Phoebe some 2\ as seen from the
earth,^ .ind will, therefore, be a readily measurable
quantity, '{'he apse moves round Saturn about f"
annually in the srmie direction as Phoebe. It is
thought that the effect of Jupiter's action on Phoebe's
motion will also be appreciable; there is a good deal
of matter here awaiting mathematical treatment, and
it is not impossible that some further light may in-
cidentally be thrown on the theory of our own moon.

Prof. Pickering gives some speculations re the bear-
ing of Phoebe's retrograde motion on the nebular
hypothesis. lie supposes the planets to have once
formed rings of matter revolving round the sun; then

since the inner portion of the ring would revolve the
quickest, when the ring coalesced into a planet the
part next the sun would be moving quickest, i.e., the
planet would be rotating in a retrograde direction.
Thus he supposes that all the planets originally had
retrograde rotations, and next asserts that this state
of things was unstable owing to the action of solar
tides, which tended to turn the planet over so as to
make the direction of rotation the same as that of
revolution. This point will need careful examination
by our leading mathematicians, but if we assume it
provisionally it will explain a good many things about
the solar system. Phoebe is supposed to have been
born in very remote ages, when Saturn rotated back-
wards; while Saturn was turned over before the birth
of Japetus and the inner satellites. It also appears
that distant satellites, like our moon, Phoebe, and
Japetus, are compelled by the sun to move in planes
near the primary's orbit ; while near* satellites, such as
those of Mars, Jupiter, Saturn (7 inner), and Uranus
(presumably) are in the equatorial plane of their
primary.

The theory explains the retrograde motion of the
Uranian and Neptunian svstems by supposing that the
solar tides have been too weak at such great distances
to turn the planets over, though Uranus would seem
to have been turned about half way, and Neptune one-
quarter of the way. Thus the new theory tends to
bring these outer planets into line with the others, and
to remove a difficulty which had always been felt with
regard to the application of the nebular hypothesis to
them. Going to the other extreme, the slow rotations
of Mercury ar^d Venus, which are now accepted by
many astronomers, would likewise find an explanation
in solar tides, so that these would seem to have left
their traces on the system from one end to the other.
They were doubtless much more powerful in distant
ages, when the planets were larger and more diffused
than they are at the present day.

* The word " near " is to be understood relatively to the size of
the primary, compared with which Jupiter's satellites are all much
nearer to him than our moon to the earth.

The Inner Nebvilace of
the Pleiacdes.

Ry Dr. Max Wolf, F.R.A.S.
The original plate of the accompanying photograph
was taken by the writer with the " A " lens of the
16-inch Brashcar twin telescope, on December 22, 1902,
with five hours' exposure. The plate was carefully
backed with a black coating, so that the well-known
halation circles do not appear round the bright stars.
The accomp.'inying photograph has been enlarged three
times from the original negative. In order to bring
out the inner nebula; it was necessary to greatly pro-
long the process of copying, so that the fainter outer
nebulae have become over-darkened. The extremely
curious straight lines of nebulous stream are very well
seen. The inclined and partly doubled stream near
Electra* is a defect and not a true nebula. We see
that all the brighter stars of the Pleiades are
systematicallv connected by streams of nebulous matter
beautifully fine in structure.

•Electra is the nebulous star 28 inches from the west side of the
plate, and 37 inches from the south'side.

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.
WEST.

289

I
h

3
0)

n
c

EAST.

igo

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

Sunspot VoLriaLtion in.
LoLtitvide.

Bv E. W.ALTKR Mainder, F.R.A.S.

\)H. Lock^er's object in his two letters would appear
to be twofold. First, to indicate his dislike of a short
note on page 159 of the July number; second, to make
a certain claim for himself. L'nder the first head he
has failed to point out a single inaccuracy in the note,
though his two letters together exceed it in length more
than ten times. I think the note stands vindicated as
having presented in nineteen lines the gist of three long
papers with truth and remarkable conciseness. Under
the second head, Dr. Lockyer introduces much wholly
irrelevant matter, but avoids the only two questions
which really bear on the point of his claim. Did he
make use of a certain paper, and if so, did that paper
already contain the result which he claims as his own,
definitely and explicitly set forth? Dr. Lockyer does
not and cannot deny that he did use the paper in ques-
tion, and that it did so contain that very result.
Whether that result confirms or contradicts Spoerer's
Law, is a matter which has no possible bearing on Dr.
Lockyer's claim to it. Xor is it, in this connection, of
the smallest significance by whom or under what con-
ditions the paper was written, which Dr. Lockyer used,
and wherein he found the result in question.

The Herschel Obelisk
near Cape Town.

We are indebted for the accompanying photograph to
the courtesy of Mr. W. H. Wesley, to whom it was sent
by Mr. Clement Jennings-Taylor, from whose covering
letter to Mr. Wesley, we are permitted to make the
following extracts: —

It inay interest you to know that my house is close to
where Herschel's old residence stood : his monument slandint;
about 100 yards in front. I am sending you a ,i;ood amateur
l)hotOi,'raph of the obelisk taken by a friend, Mr. S. Rutherford,
as I thouK'ht you might like to reproduce it. The obelisk,
which by the way forms the crest of the Claremont Munici-
pality, is very plain, and covers a small round pedestal of
Ktaiiite. This pedestal can be dimly seen in the photograph,
together with the " H " forming part of the four initials cut
deep into and round the same. On the top the date is deeply
cut, " 183S," to see which one has to crawl into the hole. A
1 )rass tablet is shortly to be fixed on one side, and 1 understand
tliat the Council is willing to find half the cost of railing the
monument round. pro\ided the remainder can be raised by
subscription— some /loo to £'150 in till. It has been neglected
of late years, and seeing that the obelisk, with some 50 or
60 feet of ground round it, is public property, it seems a pity
some protection is not arranged for. The ground about is at
present open, except for the schools just in front, but as the estate
has been cut up and mostly sold in lots, it will soon be built
over, and then will come the danger of damage. The monu-
ment is placed astronomically true N. and S., the front or
opening being due south. .'\ pretty view of the Devil's Peak
is seen above, to the left, and the oak trees make an excellent
background. The weather marks on the stone are also
wonderfully reproduced. Strange to say, a great many people

residing in the district and in Cape Town do not know of the
existence of the obelisk, and a greater number probably do
not know who Herschel was or what he did, so the lack of
interest in and care of the memorial stone may be somewhat
accounted for. I was showing it to an acquaintance one

day, when he surprised me with " Oh, Herschel ! that's the
chap who invented the steam engine, isn't it ? " Half an
hour in my little observatory opposite enlightened him on the
subject, though he confessed that " he didn't think it much of
a money-making business."

Ancient Ej^ypt. — The " Short History of .\neient Egypt "
(Constable) which has been compiled by Percy E. Newberry
and John Garstang is almost as concentrated as Bovril is said
to be by its advertisers. But whereas Bovril contains yo per
cent, of water, there is positively no dilution of any sort or
description in this most useful little work. Mr. John Garstang
is known to readers of " Knowledge " by the Beni Hasan
excavations, some account of which appeared in the August
number; and his name, like that of Mr. Newberry, is a gua-
rantee of thoroughness. Into the volume's hundred odd pages
are packed the important events of three thousand years of
Egypt's rise and fall. It aims at a scientific statement of
proven facts, and it ignores theories and traditions. It will
have a few enemies among the theorists, but it will make more
friends — for itself and for historic Egypt.

Dec, 1904.1

KNOWLEDGE & SCIENTIFIC NEWS.

291

ASTRONOMICAL.

Herr Nippoldt on the Connection between
Solar Activity and Terrestrial Magnetism.

In the October number of the Asliofiliysical Journal, Herr
A. Nippoldt, of the Potsdam Maj,'notic Observatory, criticised
a recent paper by Father Cortie on " The Solar Prominences
and Terrestrial Magnetism." The latter had endeavoured to
show that the eclipse spot i;rotip of i()0i, if it may so be called,
by far the largest spot group of the year, had no effect upon
terrestrial magnetism. Herr Nippoldt claims that .a sm.iU l>ut
e\'ident disturbance did take place duriug the pa=sage of the
spot. He is also emphatic that we have no right to assume
that no disturbance has taken place unless m.agnetic stations
near the pole have exhibited no deviations from their normal
curve. He insists that there should be no kind of statistical
definition of the idea of disturbance, that the maximum ampli-
tude can hardly be usable to decide whether or not a curve is
disturbed, and that we may represent the nature of the effect
of the solar action upon terrestrial magnelisni as a sort of
relay action — "the strength of the releasing solar activity need
not have a definite relation to the strength of the magnetic
storm." He therefore desires to sub.stitute for the statistical
method the investigation in detail, and calls for a continued
and uninterrupted registration of the changes occurring on
the sun.

The paper is most disappointingly vague and inconclusive.
The small disturbance of which he gives a trace can hardly
be said to have been ''simultaneous " with the spot, except in
a very loose sense of the term, whilst it is only by a searching
application of the statistical method that we can hope to dis-
criminate between synchronisms which are purely accidental.
and those which may be legitimately taken as establishing
connection.

* * *

Demonstration of the Solar Origin of
Magnetic Disturbances.

Quite a different method of treating this question was adopted
by Mr. E. W. Maunder in a paper read before the Royal
Astronomical Society on November 11. Tabulating all the
magnetic disturbances of 20' in declination and over, recorded
at Greenwich Observatory from 1882-1903, and computing the
heliographic longitude of the centre of the sun's disc for the
time of commencement of each disturb.ince, it became clear
at once that many of these disturbances recurred wlieu the
same solar meridian returned to the centre of the disc. lu
fact more than three-fourths of the total luuuber catalogued
(276) were included in some one of these series. There is only
one conclusion, it was urged by Mr. Maunder, to be drawn
from this relation, namely that the exciting cause of our mag-
netic disturbances was associated with definite limited areas
on the sun. Further the magnetic action, whatever its nature,
did not radiate equally in all directions, like light and heat,
but acted along verj- definite aud restricted lines. The uie.m
rotation period indicated for these areas was the same as that
given in the mean by the sunspots ; the extreme periods were
those given by what we may fairly call the extreme sunspots,
that is to say those on the equator and in latitude 30. Mr.
Maunder found an analogy to these magnetic streau) lines in
the long rays of the corona, as photograi)hed in the 1898 total
solar eclipse. The solar action being of this nature, it is per-
fectly clear that the stream lines from many spots may miss
our earth altogether, and hence a great spot need not neces-
sarily be accompanied by a magnetic storm. On the other
hand some of the disturbances recurred rotation after rotation
when the spots with which they synchronised at their
commencement had ceased to be visible. The paper there-

fore not .lii. I . M: ..,:.i, an entirely new conception of the
solar action ni producing our magnetic disturbances, but sug-
gests that there are definite .ictive .ireas on the sun, intermit-
tent in their activity, of whieli aetivity spot formation is an
important phase.

* * *

The Spectra of R Scuti and W Cygni.

Mr. Ralph II. ("nrtiss has succeeded iu photographing the
spectra of both of these stars, and found the hydrogen lines
bright at maximum. H Scuti gave a spectrum resembling the
solar type ; U' Cygni a banded spectrum, with the bands sharp
towards the violet and shaded off towards the rod.

Rotation Periods of Venus and Mars.

In till.' " Cnniptes Ki'iidus " of the I'.uis Academy, Mr. Lnwell
gives the result of a series of spectrographic determinations of
the rotation of these two planets. For Venus, the; spe(?d of
motion of a point on the equator was found to be practically
nil, the probable error of the observation only amounting to
o'oo.S kilometres per second, the result thus supporting the
idea that Venus rotates iu the same period as her revolution.
For Mars the speed was found as o'228, the computed value
being o'24i. The probalile error in the case of Mars was
0'0j6. The satisfactory result obtained for Mars lends sup-
port to that for the Larger and brighter planet.

W'c deeplv regret to recurd the death of Mr. Frank McClean,
M.A., I,L.d1, F.K.S., M.Inst.C.E. Mr. McCleau was distin-
guished for his important tpeetroscopic researches and his
liberal donations to further the cause of astronomy. His
spectroscopic work included an ekiborate series of compara-
tive photographs of the high and low sun, a fine atlas in which
he studied the comparative photographic spectra of the sun
and the metals, and a great spectroscopic survey of all the
brighter stars in the heavens. In order to render this work
complete. Mr. McClean visited the Cape (observatory iu 1897,
where for six months he carried on his survey of the southern
heavens. In the course of this work, he was able to identify
between 40 and 50 of the lines of oxygen in the spectrum of
Beta Crucis. His bt'uefacf ions to astronomy include his foun-
dation of the Isaac Newton Studentships at Cambridge, and
the magnificent photographic telescope with its fine spectro-
scopic equipment which he presented to the Cape Observa-
tory. Mr. McClean died at Brussels on the morning of
November 8 in his sixty-seventh year.

We heartily congratulate the Astronomer Royal, Sir
W. H. M. Christie, F.R.S., on his promotion to the rank of
Knight Commander of the Order of the Bath (K.C.B. Civil

Division).

* » *

Encke's Comet.

Enckc's Comet has been not only [iliotographed, but has
also been seen and observed by Professor M. Wolf at the Astro-
physical Observatory, Kunigstuhl, Heidelberg, on October 29.
It has also been observed by Professor IC. Millisevich, at the
Observatnry of the Roman College, in Rome, on October 30,
and by Professor E. Hartwig, at the Bamberg Observatory,
on Octolx-r 31. The Comet is nnich fainter than was antici-
pated, and it is feared will never be bright enough to be seen
with the naked eye.

* * *

The Parallax of Alpha. Centauri.

At the station in the southern hemisphere of the Lick
Observatory, located at Santiago de Chile, observations have
been made during the past year of Alpha Centauri, and an
average difference between the radial velocities of the two
components is found of about 5' 17 km. This may perhaps
lie due to the relative orbital motion of the two components,
and, if so, it would indicate a parallax of 076, a combined
mass of the components of i'9 that of the sun; and a mean
distance between the two components of 3-46 X 10'' km.
The parallax thus indicated is almost precisely that resulting
from heliometer observ.ations.

2g2

KNOWLEDGE & SCIENTIFIC NEWS.

(Dec.

1904.

Intermittent Disturbances on Jupiter.

In the Observatory for October, Mr. Denny arrives at the
very significant conclusion that " features exhibiting various
peculiarities of appearance and rates of motion are common
to certain latitudes and break out from time to time, enduring
for certain unknown intervals, then disappearing to be replaced
by similar phenomena." In his recent paper to the Royal
Astronomical Society, Mr. Maunder draws attention to a
somewhat similar intermittent action in the magnetic dis-
turbances observed on the earth which are associated with
certain solar longitudes.

BOTANICAL.

By S. A. Sh

The exhibition of an extraordinary- grass fruit at a meeting of
the Linnean Society was noted in the columns of "Kxowleuge"
nearly three years ago. A full account of its remarkable
structure, written by Dr. Otto Stapf. is now published ia the
last part of the Society's Transactions. The fruit is the pro-
duct of Melocanna bambiisoidcs, which belongs to the tribe
BambusesE of the grass family. It is an arborescent plant,
growing to a height of from fifty to seventy feet, and is a
native of Eastern Bengal and Burma. Unlike the ordinary
fruit of che Gramineae, which is small, often almost minute,
and albuminous, that of Mtlocanna is sometimes as much as
five inches long and two inches thick, globose or ovoid in
shape, and exalbuminous. It is also remarkable in being
viviparous, germinating before it falls from the parent plant,
but this does not appear to be a constant character. Its peri-
carp, instead of the thin, membranous or crustaceous bodv of
the usual grass fruit, serving practically only a mechanical
function, is very largely developed and is fleshy, and serves
partly as a reservoir for food material, a function which is
shared by the scutellum, though this body retains its original
character as a haustoiium. Some albumen, or more cor-
rectly, endosperm, is formed in Melocanna. but Dr. Stapf
shows that at an early stage it collapses " and is finallv
crushed into an apparently structureless film, wedged in
between pericarp and scutellum."

* * *

The latest part of the " Annals of the Royal Botanic Garden.
Calcutta," contains an elaborate monograph of the species of
Diitbergia of South Eastern Asia, by Major D. Prain, Dalbergia
is a large genus of Leguminosae (Fapilionacea;), chiefly in-
habiting the warmer parts of Asia. Its species are trees or
cUmbing shrubs insignificant in their flowers, but several are
important economically on account of their wood. Dalbergia
latifolia is the Indian Blackwood or Rosewood, valuable for
furniture. The Sissoo iD. Sissoo) supplies a timber remark-
able for its strength and elasticity. Like the excellent mono-
graphs of Qitercus, Fictis. and other genera which ha\e appeared
in the '"Annals," Major Prain's work isaccompanied by numerous
illustrations,

* * »

Wiesner, Bonnier, Warming, Schimper, and other botanists
have published observations on the influence of either
humidity, heat, or light on plant structures. Monsieur J.
Bedelian, in a series of papers appearing in the current volume
of the Revue Gincrah de Botaniqiie, shows the combined
influence of these agencies on the growth in a greenhouse of
several common plants which are found growing wild in the
neighbourhood of Paris. Specimens of such plants as the
Daisy, Dandelion, Shepherd's Purse, Plantain (three species),
and Milfoil were selected, some of each species being grown in
the open air and others in a greenhouse. The experiments
were carried on between the montlis of November and May.
During this period, especially, the conditions of heat, light, and
moisture in the greenhouse would be very different from those
prevailing outside. The heat would be greater and more
equable, the light more diffused, and there would be more
moisture in the atmosphere. The influence of cultivation in
the greenhouse on plants which normally produce a rosette of
le;ives adpressed to the soil was shown in a pronounced elonga-
tion of the intemodes whereby the rosette arrargement dis.

■ \ ^ ■ ives tended to become erect, and a marked

increase in si^e was noticed. The internal structure of the
roots, stems, and leaves of each set of specimens has been
carefully examined and compared. In general the plants
grown in the greenhouse have less differentiated tissues, less
wood is formed, cell-walls are thinner, and intercellular spaces
larger.

ORNITHOLOGICAL.

By W. P. PVCRAFT.

A Nestling Toura-cou.

At the last meeting of the British Ornithologists' Club, Mr. D.
Seth-Smith exhibited the onlj- known nestling of a Touracou.
This was of the species known as Eraser's Touracou (Turacns
inacrorhynclius). The unique character of this exhibit was still
further increased by the fact that the bird had been hatched
in confinement in the aviaries of Mrs. Johnstone, at Bury St.
Edmunds.

Mrs. Johnstone is the possessor of a pair of these birds,
which, after a preliminary but abortive attempt at nesting in
June last, succeeded, towards the end of July, in hatching two
eggs, laid in a nest of sticks placed on a hamper-lid in a rhodo-
dendron bush.

Only one egg seems to have hatched out, and the nestling
therefrom lived for four weeks, when it was killed by the cold
nights of September.

Hitherto nothing was known of the condition of the young
Touracou at birth. It was supposed that it would prove to
resemble the young of the cuckoo; but this is not the case,
inasmuch as the young cuckoo remains quite naked till the
feathers appear, while the young Touracou is sparsely clad
with down feathers, and bears a rather close resemblance to
the remarkable and aberrant Hoatzin.

The wings of this nestling were, at the time of death, of
great size, while the rest of the body remained still invested in
its downy coat. Save that it was seen to clamber about the
nefct occasionally during the day. nothing was learned concern-
ing it during life ; but it is probable that the habits of the nest-
lings will turn out to resemble those of the Hoatzin described
in our last issue.

* » *

Short-Eared Owl Nesting in Hampshire.

Mr. Trevor-Battye. iu the A'icultm-al Magiui>!e for Novem-
ber, records the breeding of a pair of Short-Eared Owls {Asio
accipitriniis) on Bransbur\- Common, where a pair of young
birds were successfully reared. This appears to be the first
known instance of the nesting of these birds in this country.

* * *

R^obins Catching Fish.

The Field. October 15. contains an interesting account of a
partv of five robins which were discovered hunting about
among the pebbles in the bed of a small stream, from which
they constantly flew on to a neighbouring wall, carrying some
live object in their beaks. On a visit to the spot being made,
a stickleback kicking vigorously was found. The observer
(who signs himself " W. H."| then retired for about ten yards
and watched their proceedings. The fish was taken from the
water crosswise, and borne from the water to the wall to be
dispatched. There seems to have been no attempt made to
kill the prev before eating, as is done by the kingfisher; but
then the fish was not swallowed alive.

A White Snipe.

A very beautiful white variety of (he Common Snipe {Gal-
linago ca-lestis) has just been received at the Natural History
Museum, South Kensington. This bird was killed at Poltal-
lock, Argyllshire. The only normally-coloured feathers were
a patch on each side of the head, meeting one another at the
crown ; a few scapulars, the tail and under tail-coverts, a few
under wing coverts, and three primaries in the left wing.

Dec., 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

293

Sheep's Wool and Birds* Legs.

At the first meelins of the winter session of the Ornitholo-
gists' Club, Mr. Ticehnrst cxhiliited a series of legs of the
lapwing taken from birds shot on Koniney Marsh during
August last. These were very remarkable, inasmuch as they
showed various stages of necrosis of the lower part of the leg,
caused by the sheep's wool having become wound round the
part atTected.

In one of these legs the wool had been successfully removed
by the bird and only a scar was left. In anotherthe wool had
so tightly encircled the toes that a partial necrosis of one
member had taken place. In a fourth specimen this ligament
had wound itself around tarso-met.itarsus just above the toes,
and in consequence these had all been lost.

A yellow wagtail with feet similarly affected was also shown.
It is worthy of note that we have no records of starlings being
affected in this way.

* » *

Spotted Crake in Antrim.

A Spotted Crake, records the Fiiht. October 22, was shot
near Tempiepatrick, Co. Antrim, on t)ctobcr 8. This makes
the sixth occurrence of this bird in .Antrim.

* * *

Solitary Sandpiper at Rye.

Mr. C. B. Ticehnrst exhibited at the t)ctober meeting of the
Ornithologists' Club a Solitary Sandpi])er {Tdtiiitus solitciniis)
shot at Rye Harbour, Susse.x, on .August 7. This is the fourth
British example of this .American species.

* » »

Ta-wny Pipit at Rye.

At the meeting of the Ornithologists' Club just referred to
Mr. C. B. Nicoll reported that three specimens of the Tawny
Pipit {Anthiis campesliis) had been taken at Kye Harbour
during August last. He himself shot an immature bird of this
species on the sea-banks of Sussex near Bexhill. From the
numerous occurrences of these birds he expressed his opinion
that the Tawny I'ipit was a regular autumn visitor on
migration.

* * »

Lapland Bunting near Pevensey.

Mr. C. B. Nicoll also reported that he had procured an
immature example of the Lapland Bunting (Calccuiiis lap-
poiiicus) near Pevensey on September 28.

* * *

Broad-Billed Sandpiper at Rye.

Now that closer attention is being paid to birds on migration
in the neighbourhood of Rye a number of rarities are being
discovered. Mr. Nicoll, in addition to the records just de-
scribed, also reported the occurrence of an immature Broad-
Billed Sandpiper (Limicola platyrhynclia), which had been shot
at Rye, Sussex. This is the fifth record of the occurrence of
this bird in Sussex.

ZOOLOGICAL.

By R LVUEKKER.

Quaggas and Wild Asses.

The present year has been noteworthy from the amount of
literature devoted to the members of the horse tribe, or
Equida. One of the latest contributions to the subject is an
article by Mr. K. T. Pocock, the Superintendent of the London
Zoological Gardens, on South African quaggas, published in
the November number of the Ainials ami Miif;a;:iiu- 1/ Natural
History. According to the author, we have to deplore the
extermination not of one, but of several distinct forms of these
animals ; the quaggas of the older writers, of which two races
are recognised, being distinct from those exhibited forty years
ago in the Regent's Park and other menageries. Without for
a moment saying that the author may not be right in his view,
it certainly does seem strange that the whole of the quagga-

sk'ns which h.i\e come down to us slumKl dillcr lioui the
animals described by the older zooloj^ists. The Asiatic and
.\frican wild asses form the sul>jcct of a paper by the present
writer published in a recent issue of Novilalcs /ootof^icic, the
organ of Mr. Walter Rothschild's zoological museum at Tring ;
an apparently new race of the " onager " from Central Asia,
now living in the Duke of Bedford's park at Woburn, being
described and figured. The description of one of the two
races of the African wild ass is based on sp<>cimcns killed in
the Lastern Sudan by Mr. N. C. Rothschild, one of which is
now mounted in the British (Natural History) Musetnn, while
there is a second in the Edinburgh Museum, and a third in
Mr. Rothschild's own collection. .As the construction of the
Suakin-Berber railway is only too likely to lead to the exter-
mination of this race, these specimens are very precious.
■<■ :<- «■

The Ancestry of the Horse.

In connection with articles on this subject, which have

.ippcared during the year in '• Knowi.kdgi; " our readers maybe

referred to one by Professor H. F. Osborn on the evolution of

the horse in America, published in the November number of

the Century Magazim-. The author is of opinion that the

modern type of horse (that is to say, the genus Equus) was

evolved in North America, whence it migrated by way of

Bering Strait into .Asia, and so into fuirope and Africa. He

is also inclined to look favourably on the theory that the

blood-horse has a dilTerent ancestry to the ordinary breeds of

ICuropc.

•x- * *

A White Racoon Dog.

I"or nianv years naturalists h.ivc bnii laniiliar with a
remarkable Japanese and Chinese animal which, although
externally somewhat like an American racoon, yet is really
an aberrant member of the dog-tribe. Those who attach im-
portance to external characters, rank the creature as the re-
presentative of a genus by itself, under the names of Nyctcr-
i-uttH pnicyanoiiUs ; while those who consider that geneiic dis-
tinctionsshould rest on important structural differences class
it with the more typical dogs, as ('aiiisprmynuinchs. TIh; New
"i'ork Zoological I'.uk possesses at the present time a pure
white racoon-dog, stated to have been brought from Northern
Jajian, which is regarded as representing a second species, for
which the name NyctiTc-utvs atbus has been proposed.
■A- -X- :(-

A New Snake-Salairvander.

The description (in the Annals and Magazine of Natural
History for October) of a new species of those strange worm-
like Inirrowiug amphibians generally known as eiecilians, but
which may be better designated in popular zoology as snake-
salamanders, would scarcely seem at first a subject for notice
in this column; but, as a matter of fact, this particular case
has a very wide and important interest. The species in
question, which comes from the Kachar district of Assam, is
described by Major Alcock under the name of Htiptif fulhri ;
and it is in regard to the peculiar geographical distribution of
the genus that the interest of the new discovery lies. With
the addition of the new species, the genus Hcrpek is repre-
sented in India, Pan;una, and West Africa ; and, as Major
Alcock remarks, such a distriliution, in the case of a worm-
like burrowing group appears altogether inexplicable on the
theory that continents and ocean-basins are permanent, or, in-
d('ed,'anything like permanent. On the otherhand, the distri-
bution of Hcrpek, together with that of certain sub-littoral
hermit-crabs, which is curiously similar, affords strong sup-
port to the now generally accepted view that India and Africa
were connected by land at a comparatively recent epoch of
the earth's history (th.at is to say, within the lifetime of an
existing highly specialised genus). The two instancesalsoadd
one more link to the chain of zoological evidence which ap-
parently points to a former land connection between Africa
and South America across the Atlantic. The Indo-African
connection, which is supported by geological as well as by
zoological evidence, would explain the presence of ccecilians in
the Seychtllis as well as the absence of the above-mentioned
littoral hermit-crabs from the cast coast of Africa. The alter-
native view to the trans-Atlantic connection between West
Africa and America (apart from one by way of the Pacific)

294

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

would be that these snake-salamanders travelled from a
common northern home down the Eastern and Western
Hemispheres, but this seems almost incredible.
» • *

The Anima.ls of Africa.

The recent discoveries of wonderful new types of extinct
animals in the tertiary deposits of the Fay um Desert of Xorth-
Eastern Africa, and their bearing on the ori.^n of the modern
African fauna, are discussed by the present writer in the
October number of the Quarterly KcvicK-, in an article with the
above heading. The new evidence shows unmistakably that
the Proboscidea (elephants and mastodons) and the Hyra-
coidea (the '"coney" of Scripture and its relatives) were
developed in Africa itself; but it does not appear to invali-
date the long accepted theory that the bulk of the modern
African fauna is of northern origin. It might, however, have
been added that, in view of the discovery of certain antelope
and other remains in the later tertiaries of Africa, the migration
may have been somewhat earlier than commonly believed.
Probably, indeed, there have been several migrations of
African types to the north, and of European and Asiatic
types into Africa,

In this connection it may be mentioned that Dr. C. W.
Andrews, the chief describer of the extinct Fayum fauna, has
brought to notice in the Xovember number of the Geological
iluf(ii:.iitc a remarkably fine shell of the giant land-tortoise,
Tistiiiio amino", of the Upper Eocene beds of the district in
question. This appears to be the earliest of the big land-
tortoises, and may have been the ancestral type from which
those of Madagascar, Mauritius, and the Mascarene Islands,
together with the extinct Indian species, were derived,

* * *

An Intelligent Chimpanzee.

Berlin possesses a successor to the late lamented chimpanzee
" Consul " in the shape of Cor.sul II., of which the following
account has been published. Recently Consul II. appeared
before a meeting of the German Psychological Society, and
was the subject of a lecture by the eminent psychologist.
Professor Hirschlaff. The ape stood on the platform beside
the lecturer in a smoking jacket, top-hat, black trousers, boots,
and shirt. Professor Hirschlaft gave Consul an excellent
character. He has good manners, is of a friendly disposition,
and manifests symptoms of what would be called in human
beings a loving nature. He has no objection to the vicinity of
dogs, cats, or snakes, but is afraid of horses. No traces are
seen in Consul of any special liking for women and soldiers.
Like most apes he delights in children, but evinces an ab-
horrence of dolls, of w-hich he can make nothing, and retires
vanquished from their presence. If Consul is tickled he some-
times shrieks with laughter. When punished he acts like a
child, holding his hands before his face. If discovered at
anything he is forbidden to do he assumes hypocritically an
innocent demeanour, which is distinctly human. He is rest-
less, and cannot sit long in one position, \\'ith an excellent
memory, he is yet incapable of expressing his wants either
by gestures or sounds. He cannot be taught to whistle, nor
does he understand human speech. All he can comprehend
is the tone of a voice or the rhythm of words ; and he cannot
be taught to reckon. Although Professor Hirschlaft said that
the psychological abilities of Consul are separated from those
of human beings by a wide gulf, it is interesting to note how
many complicated actions he can comprehend with the intel-
lectual powers he possesses.

* » ■(

Papers read.

At the first meeting for the session 1904-5 of the Geological
Society, held on November 9, the Kev. Osnmnd Fisher
read a paper on the remains of the extinct southern elephant
[F.lcphas Mcridionali.'.) found in a cleft in the chalk at Dewlish,
Dorsetshire. It was suggested that the cleft was the work ot
man, and was made for the purpose of entrapping the ele-
phants, which fell into it. At the first meeting of the Linnean
Society, held on November 3, Professor Herdman described
certain features in the gills of the Ceylon pearl-oyster. Mr,
A. W. Waters described some Bryozoa from Cape Colony,
several of which he regarded as indicating new species. At the
meeting of the Royal Microscopical Society on October 19,

Mr. W. Colver directed attention to a peculiar laminated struc-
ture at the tip of the antenna of the common flea, which it was
suggested might be an organ of smell. The following papers
were read at the meeting of the Zoological Society on Novem-
ber 15: — On Mammals from Fernando Po, and on Hylo-
choerus, the Forest-Pig of Central Africa, by Mr. O. Thomas;
on the Species of Crow-ned Cranes, by Dr. P. C. Mitchell ;
and on the Mouse-Hares of the genus Ochotona. by Mr. J. L.
Bonhote, The alleged occurrence of Pere David's deer (Ela-
phitrus davidianus) in the island of Hainan was discussed at the
same meeting by Mr. Lydekker ; and various specimens were
exhibited,

« * *

A Ne\v Wild Sheep.

Sportsmen will be interested m the description by Dr, J. A.
Allen of an apparently new species of wild sheep from North-
Western Kamchatka, belonging to the Algali group, as typified
by the magnificent Ovis amnion of the Altai. The only wild
sheep previously known from Kamchatka was O. canadensis
nivicola, a near relative of the northern races of the .-Xmerican
bighorn, Dr, .Allen, whose article appears in the Bulletin of
the U.S, National Museum, proposes to call the new sheep
(). storcki^ in honour of the collector of the type skull.

The Na.ture of Grouse Disease.

.'\mong some of those qualified to form a trustworthy opinion
the view seems to be gradually gaining ground that grouse
disease is due to the presence of parasites (Sporatozoa) in the
blood, and that, as in the case of malaria, the germs of these
parasites are introduced into the blood by the bites of insects,
the carriers in this instance being apparently midges, which
at certain seasons absolutely swarm on the moors. On the
other hand, in a fashionable weekly contemporary, a sports-
man expresses his dissent from the \iew that the infec-
tion is carried by means of the midge. He may be
pardoned for urging that the disease sometimes makes its
appearance at seasons when midges are scarce ; but when
he proceeds to state that " if the midge by biting the grouse,
a thing which has yet to be proved, infects him with virus so
deadly, it is strange that men and deer, whom he certainly
does bite, suffer nothing more than temporary irritation," he
displays ignorance of some of the first principles of the
subject. It may be added that there are still people who
refuse to believe that malaria is propagated by means of
mosquitoes.

* * *

Two More Extinct Anima-ls.

.■\ writer in the I uld points out that two animals have com-
paratively recently become extinct without attracting notice on
the part of naturalists. The one is the great straight-horned
race of the Indian buffalo (Bos biihalis macrocerus), which used
to be met with, although rarely, in the Assam jungles as late as
the "forties." The second is the wolf of the Falkland Islands
(Cants antarcticiis), an interesting but perhaps introduced
species which appears to have been exterminated by strych-
nine during the " seventies."

-.-f -^ ^

Jerboa-s atnd Birds.

.\ curious structural resemblance has recently been pointed
out as existing between the skeleton of the hind-leg of that
pretty little Egyptian hopping rodent the jerboa and the same
part in birds. In both the mammal and the bird the lower
part of the leg is formed by a long, slender cannon-bone, or
metatarsus, terminating inferiorly in triple condyles for the
three long and sharply-clawed toes, the resemblance being
increased by the fact that in both cases the small bone of the
leg (fibula) is fused with the large one (tibia). It is further
pointed out that in mammals and birds which hop on two legs,
such asjerboas, kangaroos, thrushes and finches, the propor-
tionate length of the thigh-bone or femur to the tibia and foot
(metatarsus and toes) is constant, being 2 to 5 ; in animals, on
the other hand, such as hares, horses, and frogs, which use all
four feet the corresponding lengths are 4 to 7, It will, of
cours?, be obvious that the resemblance between the jerboa's and
the bird's skeleton is entirely owing to adaptation to a similar
mode of existence. An interesting point in connection with
the jerboa is that in the young the proportion of the femur to
the rest of the leg is the same as in ordinary running animals.

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

295

Further, at an early stayc 01 dcveiopuRiu ilic tiluil.i is a com-
plete and separate bono, while the throe inetatars.als which
subseijuently fuse together to form the cannon-bone are like-
wise separate.

^- * *

Were Our Ancestors Negroes ?

.An extremely interesting point with regard to the ancestry
of the Enropean or Cancasian naces of mankind has been
recently raised by certain discoveries on the Continent. It
appears that the .-Vnthropological Society of Paris has recently
received two ancient skulls, the one from the dolmen of
Pointe-de-Conquet. and the other from a tunmlus in Brittany,
both of which are distinctly of the negro type. Again, two
other skulls of a similar type have been discovered in the
cave of Baonsso-Ronsse, near Montone; while two more are
recorded from the valley of the Rhone, in \'alais, which belong
to a more modern age. .-Vll these exhibit the characteristic
negro feature of projecting jaws (prognathism), although it is
not stated whether this is accompanied by the large teeth
distinctive of modern negroes.

This indicates that the prognathic type of sknll made its
appearance occasionally among onr prehistoric ancestors, as it
does indeed now and then among ourselves ; whether, how-
ever, this is due to direct inheritance, or whether it is sporadic,
there is no evidence to show. Neither can we pronounce with
any degree of certainty whether our earliest ancestors were or
were not negroes.

R^oyal Society.

Awa.rd of Medals.

StBjOi.vED is a list of this year's recipients of the
medals in the gift of the Royal Society, the presenta-
tion of which took place at the anniversary meeting on
St. Andrew's Day, November 30 : — The Copley gold
medal to -Sir William Crookes for his experimental
researches in chemistry and physics ; the Rumford gold
medal to Prof. Ernest Rutherford for his investigations
into the properties of radio-active matter ; Royal gold
medals to I'rof. William Burnside and Col. Da\id
Bruce, respectively, for mathematical researches and
for researches into the causation of various tropical
and other diseases ; the " .Sir Humphry Davy " gold
medal to Prof. W. 11. Perkin, jun., for his work in
synthetic organic chemistry ; the Darwin silver mcd.il
to Mr. William Hateson for in\estigations in heredity
and variation ; the " Da\id Henry Hughes " gold
medal to Sir Joseph Wilson .Swan for his practic.il
applications of electricity ; the .Sylvester bronze medal
to Prof. Georg Cantor, of Halle, for researches in
pure mathematics.

Copley. — The name of .Sir William Crookes is one
of the most familiar amongst ICnglish scientific men ;
instinctively we associate him with the most fruitful
chapters in the record of physical science of the past
half-century. In his hands spectrum analysis has
yielded a rich harvest of results. I-ong ;igo,

by its aid, he discovered the element thallium.
Electrical science has been consistently advanced
through his deductions and experimental skill, ex-
emplified by a series of investigations, all the more
sure because never hurried. Following the recogni-
tion of radium by the Curies, he became an ardent
student of the problems surrounding its behaviour and
properties. In this connection his researches (with

.^ir janios Dewar) on llu' olloci nl oxlronio culd on llie
em.inations of radiimi may be instanced. Mention,
too, should be made of the invention of the ingenious
Spinthariscope, which demonstrates to the eye those
scintillations proceeding from radiinn nitrate which, in
his own apt words, con\ey the appearance of a
" turbulent luminous sea." .Sir W. Crookes' mcd.illic
roll of honour comprises, in addition to the present
award, the Uoval modal (1875), and the Davy medal
(18SS).

Rumford. — Prof. ICrncst Rutherford, whom, bv the
wav, the Cambridge .School of IMnsicists include in
their ranks, since he was a pu|)il ol I'rof. J. |. Thom-
son, is one of the younger workers in the department
referring to r.idio-acti\e matter. His paper, " On a
Radio-active .Substance limitted by Thorium Com-
pounds," was an introductory of profoimd significance
to those engaged in the higher realms of physical
inquiry.

Kayal. — Prof. \\'. Bmnside is a voluminous writer
on mathem.atic.'il subjects, p;irticularly on the Theory
of Functions (Proceedings, Cambridge Philosophical
.Society), and the Theory of Croups. Col.
David Bruce R.A.M.C., has rendered valuable
ser\ice in that comparatively new field of
inquiry wliicli embraces the study of the causation of
tropical diseases, in particular, " Malta " Fe\er, Tsetse
l-"ly Disease, and Sleeping .Sickness, a department of
work in which |)athology, medicine, and entomology
h.ave each a share as agents of discovery and pre-
vention. Ten years ago he was p.atiently carrying out
investigations in Zululand on the diseases " X'gana
and Tsetse Fly. He showed that in character they
were identical ; further, that the insect known as the
tsetse fly was, in reality, the carrier of the parasitical
organism (Trypanosome), whose presence entailed
p.athogenic consequences. This was a new observa-
tion, .and it marked a long stride forward. .Xs the out-
come of researches conducted last year in Uganda, he
supplied the proof (removed from conjecture) that
.Sleeping .Sickness, or what is now cilJcd Try-
panosomiasis, is induced by a microscopic parasite oc-
curring in the blood of the himian subject ; moreover,
that a spei'ios of the tsetse fly (Glosiiini fii/palis) acts
;is the carrier of the organism. " ..- *»

Davy. — Prof. W. H. Perkin, jun., was formerly
Lecturer and Research .Assistant in the Dyeing Depart- ,,

ment, Yorkshire College, Feeds. He is the author of ' ' //
numerous papers on the colouring matters of plants,
especially those of Indi.an origin. It is, however, for''
his long-continued and fruitful researches a'nd" fWs- •'''^ •■
coveries in synthetic organic chemistry that he receives
the medal.

Danv'in. — -Mr. W. Batoson's investigation of heredity
•and variation problems have attracted wide attention.
He has redeemed from seclusion the labours of the
natur.-ilist .Mendel, and directed a large body of workers
to the important f.-icts indicated by the studies of that
observer.

Hughes. — .Sir Joseph Wilson .Swan's scientific
labours have been concerned principally with the intro-
duction of improvements in the applications of elec;-
tricity and of the chemical arts in relation to
photogr.iphy. The adoption and development of
electricity as a mode of lighting is intimately associ;it;-d
with his invention of the incandescent electric lamp.
He w;is the first to use a filament of carbon.
Origin.ator of the autotype process, he has in other
directions aided photography in the dual aspects of
art and scien<-e.

296

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec , 1904.

Science at St. Loviis.

An exhibition on such a very grand and hitherto un-
equalled scale might have been expected to have intro-
duced some wonderful novelties to the sight- seeing
public, hut, as it so happens, no startling new inventions,
or specially peculiar constructions, have been forthcoming
to add to the attractions at the St. Louis Fair. While
speaking of this as an exhibition on an unequalled scale,

but little attention from visitors. We shall hope to give
a separate and full account of this later on.

On wandering through the vast buildings of Transpor-
tation, Electricity, Machinery, and Varied Arts, one
eagerly looks for some new and interesting object or
contrivance, but in vain. There are huge modern loco-
motives, interesting models of many old engines, motor
cars of all kinds ; there are enormous plants for generat-
ing electricity, turbine engines, and various methods of
electric lighting. Among the latter are two forms still
but little known to the linglish public, the Cowper-

Composite J^icttire ot Iwn Mfreo>coplc Views. e.Tch

^ H. '-^^.-^ 1^1, ill,'..

injr alternate stripes.

^ortiun of Picture ilett hand top corner), enlarged to
<ihow system of stripes.

we njay quote some figures as giving an interesting

summary of the area under roof of shows of a similar
nature.

London, 1851 .. .. .. .. 21 acres.

I'aris. 1867 . . . . . . 37 •■

Philadelphia, 1876 .. .. (JS ..

Paris, iSig . . . . . . . ■ 75 ■.

Chicago, 1893 . . .. .. 200 ,,

Paris, igoo . . . . . . I-5 ,,

St. Louis, 1904 .. .. .. 250 ,,

The total area of grounds occupied increased in an even
larger ratio, the acreage at St. Louis amounting to some
1240 acres.

The excellent design of the buildings and laying out
of the grounds, and the vast number of exhibits render
this a truly notable exhibition, and it seems hardly likely that
it will be exceeded in the near fuUire. The immense cost
is said to be far above the actual profits, which does not
augur well for future rivals. Bad luck, or rather lack of
good luck, has proved very detrimental to the under-
taking, and, notwithstanding the offers of huge prizes for
airships and other attractions, no exhibits of special
novelty or interest have been acquired. To this statement
there is perhaps one exception, and that is in the great
solar-heat concentrator being erected by Prof. Himalaya.
Yet this apparatus, which may not even prove to be as
wonderful as the inventor anticipates, is, towards the end
of October, not yet completed, and therefore has attracted

Hewitt and the Nernst. But these are hardly to be
classed as scientific novelties, and, indeed, are not exhi-
bited as such. The mercury vapour lamp, with its weird
blue effects, is to bs seen in each of the many photo-
graphers' studios, as well as among the illuminations of
the grounds. With many exhibits there is a notable lack
of proper labelling, and many an interesting object may
be passed by unheeded on thi.■^ account. For instance, the
new Edison storage battery is, of course, well to the fore,
but though there are a number of them exhibited there
is no descripti\e account to give particulars, which would,
without doubt, be widely read.

A conspicuous feature in the grounds is the tower
forming the station of the L)e F'orrest Wireless Tele-
graph. But we are now getting so accustomed to this form
of cmmunication that it excites but little more interest
than would an ordinary telegraph office. In the Aeronau-
tical sheds are two or three strange aerial leviathans, though
experts seem agreed in not anticipating any very special
advance in aerial navigation by their means. Besides
various specimens of kites for meteorological work, shown
by the Governments of both the United States and
Germany, are the models of Prof. Langley's aeroplane
machines and a model of the Deutsch airship.

In the Electricity Building are two diflerent instalments
of "Wireless Telephone " apparatus. One is the " Kadio-
pbone," by means of which sound is conveyed along a

Dec, 1904.]

KN(MVI KHGE & SCIENTIFIC NEWS.

297

powerful beam of light, and here is certainly an interest-
ing exhibit, although the system has been before the
scientific world for some years. From a practical point
of view, the invention may seem disappointing, for at the
transmitting end a man shut in a sound-tight cupboard
blows a loud bugle, the sound of which is conveyed by
the searchhght to a distance of only 150 feet, when it is
received on a silenium cell, and is very faintly audible in
a telephone receiver. The other wireless telephone is on
the Miller- ReeceHutchison system, in which the trans-
mitter is connected with a large coil of wire underground,
and the receiving telephone with a coil held in llie hand.

Elsewhere exhibits are given of the properties of liquid
air and of thermit, extremes of cold and heat which may
not be familiar to many visitors.

Of course, several methods of obtaining photographs
in natural colours are to be found among the profusion of
exhibits. Mr. Cowper Coles shows specimens of electric-
ally deposited metals and the differences of surface
obtained by rotating the cores at various high speeds
while the coat is forming.

LEFT EYE

RICH! Ere

Dia^am to show how one eye sees one series of stripes while
the other sees only the other series.

The Delaney system of rapid automatic telegraphy is
one of the interesting novelties shown. This is a perfo-
rated tape machine designed to overcome the tendency
existing in other machines of this sort to blur the dots
and dashes when sent over a long line. In the perforat-
ing apparatus the depression of the key causes a magnet
to operate a punch near the upper edge of the tape, while
the release of the key brings into operation a punch near
the lower edge, so that as the tape is travelling forward
the dots and dashes are distinguished by the angular dis-
tance of the holes. In the transmitting machine the
upper holes give connection to a positive current, while
the lower ones give a negative current ; so that impulses
are sent through the line which are not blurred by the
static capacity of the cable. It is said that in laboratory
experiments messages have been sent at the rate of Sooo
words per minute, and even over lines 1000 miles long a
speed of 1000 words a minute has been attained.

A fascinating instrument to watch is the Telautograph,
for reproducing at a distance handwriting, sketches, and
similar matter — in fact, a " writing telegraph." The
transmitting and receiving instruments are so arranged

that ; n the latter moves synchronously with the

transiuiiimy pencil. The operation is as follows : —

-At the transmitter the sending pencil is attached by
two light rods to two lever arms which carry contact
rollers at their ends. These contact rollers bear against
the surface of two current-carrying rheostats, and the
writing currents pass from the rheostats to the rollers,
and from them to the line wires.

When the pencil is moved, the position of the rollers
upon the rheostats is changed, and currents of varying
strength go out upon the line wires.

At the receiver these currents pass through two
light vertically movable coils, which are suspended in
uniform magnetic fields, and which move up or down
against the pull of retractile springs, according to the
strength of the line currents. The motion of the coils is
communicated to a set of levers of the same length as
those in the transmitter. At the junction of the levers is
mounted the receiving pen, which by the motions of the
coils is caused to duplicate the motions of the transmit-
ting pencil.

The paper is supplied from rolls beneath the trans-
mitter and receiver, and is shifted off the writing platens
as it is used.

Another machine worth looking at is a Hydro-Pneu-
matic Kock Drill in operation, driving holes li inches in
diameter through a lump of solid granite at a rate of
nearly 6 inches a minute. This runs at a speed of about
1000 strokes a minute, the length of stroke being about
an inch, and the tool being turned i-iith of a revolution
each stroke.

An interesting system of obtaining a stereoscopic effect
by means of a lined screen is exhibited, and, as no descrip-
tion of the method seems to have been published before,
it may be interesting to describe shortly the general
principles involved. 1 1 is called the Parallax Stereogram.
Two photographs are obtained by twin stereoscopic
lenses in the usual way, except that a screen is interposed,
formed of fine parallel lines at intervals equal to their
thickness (100 to the inch). Each negative will then
consist of a series of stripes. The negatives are
then exactly superposed so that the stripe left blank on
the one coincides with the stripe containing the picture
on the other. Th e resulting image, presenting a most
sorry effect, may be seen on opposite page. But if
this picture be viewed at a certain distance off, with
the screen suitably interposed, the right eye will only
be able to see one picture, while the left will only be
able to see the other. The result is that the subject
appears to stand out in high relief.

Tiiosr; who have a fondness for Nature in her quieter moods
and a love for Natural History will find in " Notes of an East
Coast Naturalist," by Arthur Patterson (Methuen) a very
charming companion and guide. That the author writes with
a first-hand knowledge of his subject is evident, both from the
originality of his observations as well as from the spirit of
enthusiasm which is manifest in every page. His glimpses of
the bird-life of the mud-fiats, marshes, and sea-shore in the
neighbourhood of Great Yarmouth are really delightful. We
fully sympathise with the author's sentiment against shooting.
Though atone time an enthusiastic gunner, he assures us that
he had derived far more pleasure in studying the bird-life of this
district by the aid of field-glasses. The short sketches con-
cerning the fish fauna of his neighbourhood are teeming with
interest, and contain some shrewd observations well worthy of
careful consideration. As much also maybe said for his notes
on the Crustacea of the district. Space forbids a larger notice
of this book, l>ut we most heartily recommend it. The coloured
illustrations are in many cases extremely good. Hut for the
artist's name on the plates,we should have attributed many
of the figures of the birds to G. E. Lodge and A. Thorburn.

298

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

The Administra^tion. of
Chloroform.

The arrangements for the tntertainmeut of the French
doctors last month included a visit to the fine research labora-
tories that have recently been installed at the headquarters of
the University of London, in the buildint,' which the University
now shares with the Imperial Institute, in South Kensington.

The French visitors were conducted through the various
departments of the laboratory by the Director, Dr. Waller,
and showed much interest in the work at present going on in
electro-physiology, which is made a special feature there. Dr.
Waller subsequently demonstrated the graduated administra-
tion of chloroform as an anajsthetic.

Since the institution of a Special Committee in 1901 by the
British Medical Association to inquire into the administration
of chloroform, and cause of the dangers too frequently attend-
ing it, various forms of apparatus have been brought forward
for the graduated dosage of chloroform. The importance of
the subject must infallibly be recognised in view of the too-
frequent deaths occurring from chloroform anaesthesia, and of
the painful nausea that so often results from its administra-
tion. Nor again, is it sufficient that the apparatus shall be
" capable of delivering graduated amounts 1 if chloroform under
laboratory conditions ; that method or apparatus is the safest
by which under clinical condition?, and in spite of the unavoid-
able irregularities due to the anaesthetist or the ana:sthetised,
greatest uniformity and regularity of chloroform intake shall
be maintained."'- . . . The two forms of apparatus that
conform best with this requisition are the Duliois pump and
Waller's wick vaporiser. The former delivers a known volume
of chloroform and air, at percentages variable from 1-3 per cent,
with gradual and regular induction of anaesthesia, which is
easily controlled. This instrument, however, is complicated
and expensive. The other and more portable form of evapo-
rator is an ingenious adaptation of the wick carburettor used
in certain kinds of motor cars. In overhauling and dissecting
a Daimler car. it occurred to Dr. Waller that " if by evapora-
tion from wicks, enough petrol vapour can be got to drive a
heavy car at high speed, it should be an easy matter to find a
wick surface capable of supplying 1-2 per cent, of chloroform
vapour to, say, 10 or 15 litres of air per minute, i.e., in liberal
excess of the volume of air normally breathed, which may be
reckoned as 5-6 litres per minute. (The average volume of
chloroform vapour required is 100-200 cc. per minute; a wick
carburettor will afford something like 100 litres of petrol
vapour per minute.)" +

The wick vaporiser has been tested clinically at St. George's
Hospital, and the principle of dosage by delivery from wicks
returning a known strength of chloroform vapour in air proved
entirely successful. It should be added that in this and other
similar apparatus the percentage delivered is verified by the
method invented by Drs. Waller and Gcets for i^'c'tf^hing the
CHClj vapour.

For laboratory purposes also the wick vaporiser has ap-
proved itself. K demonstration of the action of choloro-
form on cats and rats, with both forms of inhaler, was given by
Dr. Waller to the French doctors who visited the Physiological
Laboratory of the University of Londcin. The wick vaporiser de-
livers about 2 ; per cent, of CHCL and air. The animals invari-
ably go under quietly with no sign of distress or struggle, and
recover perfectly, even after prolonged ana:-3thesia. The treat-
ment may be repeated day after day with no injurious effects,
and it is even reported in the laboratory that one kitten con-
tracted the chloroform habit, and pleaded for its daily anae-
sthetic.

The anaesthesia of small animals up to 10 or 12 kilos in
weight is induced in a 15 or 30 litre jar, into which air is
pumped through the vaporiser by foot bellows. The anaesthe-
sia is subsequently maintained through the tracheal tube con-
nected with the vaporiser. The depth of anaesthesia is under
complete control, the strength of mixture being raised or
lowered as required by raising or lowering the wicks of the
vaporiser. Frances A. Welby.

' A. D. Waller, " Examination of Apparatus proposed for the
Quantitative Administration of Chloroform." — Lancit, July 9, 1904.

i Pi.. D. Waller, Proc. Physiol. See, Aug. 19, 1904. Vol. xxxi.
Journal of Physiology.

Chimpanzis and
GorilloLS.

Bv K. LVDEKKER.

The recent arrival and lamented deaths of the two
30ung' gorillas at the Zoological Society's menagerie
in the Regent's Park have given rise to a considerable
amount of popular interest in these great tropical
.African apes and their near relatives, the chimpanzis.
.'Vccordingly, it is a fit opportunity to devote an article
in " Knowledge .and Scientific News " to the con-
sideration of some of the leading characteristics of
these two species and their relationship to one another.
In referring to these animals as being represented by
two species only, I am quite aware that I am going
against the views of several of my brother naturalists,
who are of opinion that there are several species both
of gorillas and chimpanzees. My own opinion, on the
other hand (and it cannot be too strongly emphasized
that what does or does not constitute a species is
merely a matter of opinion, and is, moreover, a matter
of little or no importance), is that these so-called
species are really local races, or sub-species; and that
there are only two distinct types of great .\frican apes,
the chimpanzi {Anfhropopiihcctis troglodytes), and the
gorilla (Anthrnpflpithccus gorilla). Here again I fear
that I shall be treading on the toes of some of my
naturalist friends, who prefer to regard the larger of
the two species as representing a genus by itself under
the name of Gorilla ; but from the fact that it is in
some cases very difficult to decide whether a particul.ir
ape should be classed as a chimpanzi or a gorilla, it
appears little short of an absurdity (even admitting
that genera, like species, are merely expressions of
individual, or it may be collective, opinion) to regard
each as the type of a genus by itself. One other point
in connection with preliminaries, and I have done. It
will be observed that throughout this article the
common name of the smaller of the two apes is spelt
chimpanzi instead of the familiar chimpanzee. This
has been done in order to be in uniformity with the
spelling of names like Fiji and okapi, for it is m;mi-
fest that if we spell such names with a final /, we
should do the same in the case of chimpanzi and manati.
It may be added that the two latter names, like okapi,
should probably be pronounced with the accent on the
second, instead of on the final, syllable.

Both the chimpanzi and the gorilla are ranked by
naturalists among the man-like, or anthropoid, apes,
and are the onlv living .African representatives of that
group which includes, however, the orang-utan of
Sumatra and Borneo, and the gibbons of Assam and
the Malay countries. The man-like apes, it may be
observed, differ, among features, from baboons and
monkeys, by the absence of a tail, of pouches in the
cheek for storing food, and of callosities, or hard
patches, on the buttocks, as well as by the circum-
stance that the breast-bone is flattened from back to
front instead of from side to side, being, in fact, a
depressed instead of a compressed bone, and thus
better adapted to permit the free use of the arms in an
upright posture. In all these respects, as well as in
the structure of the cheek-teeth, which are quite unlike
those of monkevs and baboons, the man-like apes re-
semble man himself ; and of all the four existing
generic types of the former, the chimpanzi and the

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

299

gorilla are the two which approximate most nearly to
the human type, the chimpanzi being' structurally the
nearer of the two to man, although the gorilla marks
a step in the direction of the latter by its much less
completely arboreal habits. Roth the African species
are normally black or blackish in colour, and dift'er
strikingly from the orang in that there is no marked
and decided difference in the form of the face and head
in the two sexes ; the male merely showing in this
respect an exaggeration of the structural features of
the female. In this respect they again- show a decided
approximation to the human type. For a long period
both species were believed to be confmed to the tropi-
cal forests of the West Coast of the Dark Continent,
but the chimpanzi was ascertained by Schweinfurth
and Emin Pasha to range into the Xiam-niam country
and Kast-Central .Africa, and quite recently the gorilla
has been found to ha\e a somewhat similar dis-
tribution, so that their habitat may be taken to
include a large part of the equatorial forest belt. That
the ancestor of the group was not, however, a native
of .Africa may be inferred with considerable probability
from the fact that the jaws of a fossil chimpanzi have
been discovered in the later Tertiary deposits of N'orth-
Eastern India; and it is not a little remarkable that in
some particulars the teeth of this extinct Indian chim-
panzi come nearer to those of man th.in do those of
either of the two living .African man-like apes.

Of the two sp(:cies, the chimpanzi has been for much
the longer time known to European science, Dr. Tyson,
a celebrated surgeon and anatomist of his time, having
dissected a young individual, and described it, .is a
pigmy, or Homo sylveslris, in a book published so long
ago as the year i6gg. Of this baby chimpanzi the
skeleton is still preserved, and may be seen any day in
one of the bays of the central hall of the Natural
History Branch of the British Museum alongside the
volume in which it is described. It was not, however,
till nearly a century later (1788) that the chimpanzi
received what is now recognised as a valid scientific
name, having been christened in that year Siniia
iroglndyies by the French naturalist (imelin. In his
classification it was included in the same genus as the
orang-utan, but since such an arrangement scarcely
coincides with modern ideas of systematic zoology, it
is now generally known as Atilhropopithccus troglodytes.
\\'hether any stickler after priority will seek to revive
Tyson's name, and call the creature Anihropopithccm
sylveslris, remains to be seen. If he does so, and the
change be adopted generally, the chimpanzi would
have a much more appropriate designation than it has
at present, the " man-like ape which dwells in the
woods " being infinitely superior to the " m;ni-likc
ape which dwells in caves," since the chimpanzi is an
arboreal and not a spela?an animal.

As regards the history of the second and larger
species, it was at one time supposed that the apes en-
countered on an island off the West Coast of .Africa by
Hanno, the Carthaginian, were gorillas, but in the
opinion of those best qualified to judge, it is probable
that the creatures in question were really baboons.
The first real account of the gorilla appears to be one
given by an English sailor, .Andrew Battel, who spent
some time in the wilds of W'est .Africa during and
about the year 1 ^gr) ; his account being^ preserved in
Purchas's " Pilgrimages," published in the year 1748.
From this it appears that Battel was familiar with both
the chimpanzi and the gorilla, the former of which he
terms engeco and the latter pongo — names which ought
apparently to be adopted for these two species in place

of those now universally in use. Between Ballel's
time and 1846 nothing apj^ears to have been heard nt
the gorilla or pongo, but in that year a missionaiv at
the (iabun accidentally discovered a skull of the huge
ape; and in 1847 a sketch of that specimen, together
with two others, came into the hands of Sir Richard
Owen, by whom the name CioriUa savagci was pi'oposed
for the new ape in 1848. L'nfortunalely Dr. .Savage,
a missionary at the (iabun, who sent Owen inlormation
with regard to the original skull, hiniseU' pro|josecl the
name Troglodytes gorilla in 1847, and this specific name
accordingly stands. The first complete skeleton of a
gorilla sent to ICurope was received at the Museum of
the Royal College of Surgeons in i8,si, and the liist
complete skin appcu's to have reached the Briti>h
Museum in 1858.

Adult gorillas have nevei- been seen alive in captivity
—and probably never will be, as the creature is fero-
cious and morose to a di'gree. In .-uldition to the two
which made such ;ui unfortunately brief sojourn in the
Regent's Park during the present year, a few other
immature examples have been brought alive to this
country. Of these the following account is repro-
duced from the " Zoological Notes " column in a
recent issue : —

■' Only two have, however, been previously exhibited
in the Regent's Park. The first of these was a young
male, purchased ii; October, 1887, from Mr. Cross, the
vyell-knovyn Liverpool dealer in animals. .At the time
of .irrival it was supposed to be about three years old,
and stood 2^ feet in height. The second, which was
a mall', and considered to be rather older, was .-ictiuired
in .March, i8q6, having been brought to Liverpool
from French Congoland by on- of the .African Steam-
ship Company's vessels. It is described as having
been thoroughly healthy at the date of its arrival, and
of an ;unial)le and traiMable dis[)osition. Neither of
these animals suvived long."

So long ago as the year 185:5, when the species was
known to zoologists only by its skeleton, a gorilla was
actually living in this country. This animal, a young
female, came from French Congoland, and was kept
for some months in Wombwell's travelling men.igeric,
where it was treated as a pet. On its death, the body
w.-is sent to the late Mr. Charles Waterton, of Walton
Hall, by whom the skin was mounted m a grotesque
manner', ruid the skeleton given to llv; Leeds Museum.
.Apparently, however, it was not till several years later
that the skin was recognised by the late Mr. A. D.
Bartlett as that of a gorilla : the animal having
probably been rcgarded'by its owner ;is a cliimp.anzi.

Chimpanzis, on the other hand, ai'c comp.aratively
common in captivity, although luost are finite young,
.and only a few sin-vivt' to .-uivthing approa<-hing
maturity.

Between a typical chimpanzi and a typical gorilla
there is no difiiculty at all in drawing a distinction;
the diiliculty comes in when we have to deal with the
aberrant races (or species) of chimpanzi, sonv of
which are so gorilla-like that it is somevvh.at hard to
decide to which species they really pert.ain. The
ordinary chimpanzi, especially in the young state,
is such a familiar animal that a portr.-iit is unnecessary.
In height the adult male does not exceed Wxii feet,
and the colour of the hair is :i full black, while the ears
are remarkably large and prominent, and the hands
reach only a short distance below the knees. The
head is rounded and short, without prominent beetling
ridges above the eyes, or a strong crest along the
middle line of the back of the skull; while the tusks

300

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

of the old males are of no very great length and
prominence. Gentleness and docility are specially
characteristic of the species, even when full-grown;
while in the nati\e state its haljits are thoroughly
arboreal.

What a contrast between such a creature and an old
male gorilla, one of the most savage and untamable
beasts on earth, with the eyes overhung by a beetling
penthouse of bone, the hinder half of the middle line
ot the skull with a wall-like bony ridge for the
attachment of the powerful jaw-muscles, and the
tusks of monstrous size, and recalling those of a
carnivorous animal. These characteristic traits are
well displayed in the accompanying photograph (Fig.i)
of the head and bust of a huge male gorilla shot by
Mr. H. Paschen in the hinterland of the Cameruns, and
now in Mr. Rothschild's Museum at Tring, which also
exhilsits the relatixcly small size of the cars and the
elongated form of the head distinctive of the gorilla.
Another characteristic of this species is the small size
of the thumb and the length of the arm, the latter
reaching to the middle of the shin-bone.

Fig. 1.— Bust of Male Qorilla from the Cameruns.
(After H. Paschen. I

If we had only these two typical forms to deal with,
there would be, as already said, no possibility of con-
founding a chimpanzi with a gorilla. When, how-
ever, we pass into Central Africa we find the chim-
panzis assuming more or less marked gorilla-like traits
which render the distinction in some cases a matter of
difficulty. The first of these aberrant types is Schwein-
furth's chimpanzi [AnlhrnpopilIiccKs troglodytes sclnvcin-
-fiiriln), which inhabits the NIam-niam country, and,
although evidently belonging to the same species as
the typical race, exhibits certain gorilla-like features.
These traits are still more developed in the bald chim-
panzi [A. t. /sc/icgo), of Loango and the hinterland of the
Gabun and French Congoland, which takes its English
name from the sparse covering of hair on the head.
The most gorilla-like of all the races is, however, the
kulu-kamba chimpan/i (A. /. ktilu-kumba) of du
Chaillu, which inhabits Central .\fric;i. The celebrated
ape " Mafuka," which Ii\ed for some time in the
Dresden Zoological Gardens during 1875, ^"d came
from Loango, was app.arently a member" of the bald
race, although it was at one time regarded as a hybrid
between a chimp.anzi and a gorilla. The gorilla-like
features in the head .ire well displaved in the accom-
panying photograph (Fig. 2), which was taken im-
mediately after de.ath.

The.sp gorilla-like traits are still more pronounced in
the subject of tlgurc 3, \vhich is t.ikm from " johaima, "
a female chimpanzi living in Harmun ;m(l H,-iiley's slif)w
in 1899; the figure being reproduced from one illus-
trating a paper on that animal by Dr. Keith. The heavy
ridges over the brow, originally supposed to be distinc-

tive of the gorilla, are particularly well marked in
"Johanna," and they would doubtless be still more
noticeable in the male of the same race, which seems to
be undoubtedly du Chaillu 's kulu-kamba. .Still, the
large size and prominence of the ears proclaim that

Fig. 2. — Head of Female Kulu=Kamba Chimpan/i "Mafui^a.*' (From a
photograph lent by Dr. H. B. Meyer.)

both " Mafuka " and " Johanna " were chimpanzis
and not gorillas. A gorilla-like feature in " Johanna "
is, howe\er, the presence of large folds at the sides
(ala) of the nostrils, which are absent in the typical

Fig. 3.— Female Kulu = k'amba Chimpanzi "Johanna." (From the^plate
in the Zoological Society's /'f("('('(/j'(;/,s- illustrating Dr. Keith's Memoir.)

chimpan/i, hut In the gorilla extend down to the upper

Dr. Keith, who has paid special attention to the
subject, is, indeed, of opinion that, in addition to its
smaller and flatter ears, the gorilla may be best dis-

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

301

tinguishcd from the chimpanzi by tlic presence of this
great nasal fold running to the margin of the upper
lip, bv the large size ajul peculiar characters ot the
tusks and cheek-teeth; by its broad, sliort, thick hands
and feet, of which the lingers and toes are partially
webbed; by the long heel; and by the relative length of
the upper half of the arm as compared with the fore-
arm. .An important distincti\e featme c.f the skull of
the gorilla is the great length of the nasal bones.
Finallv, in life the gorilla is sharply differentiated
from the chimpanzi by its sullen, untaiiialjle, ferocious
disposition.

As regards the relationship existing between the
gorilla and the chimpanzi, Dr. Keith's observations
are so important and so interesting, that they may be
quoted, with a few verbal alterations, at length : —

" .\n examination of all the structural systems of the
.\frican anthropoids leads to the inference that the
gorilla is the more primitive of the two forms, and
approaches the common parent stock more nearly than
does the chimpanzi. The teeth of the gorilla, indi\ idu-
allv and collectively, form a complete dentition, a
dentition at the very highest point of development;
the teeth of the chimpanzi show marked signs of retro-
gression in development both in size and structure.
The muscular development and the consequent bony
crests for muscular attachment of the gorilla far sur-
pass those of the chimpanzi. The muscular develop-
ment of the adult chimpanzi represents that of the
adolescent gorilla. Some of the bodily organs of the
gorilla belong to a simpler and earlier type th;m those
of the chimpanzi. But in one point the chimpanzi
evidently represents more nearly the parent form- — its
limbs and body are more adapted for arboreal locomo-
tion; of the two, the gorilla shows the nearer approach
to the human mode of locomotion. On the whole, the
evidence at our disposal points to the conclusion that
the chimpanzi is a derivative from the gorilla stock, in
which, with a progressive brain-developiiient, there
have been retrograde changes in most of the other
parts of the body. The various races of chimpanzi
differ according to the degree to which these changes
have been carried."

In conclusion it should be mentioned that four types
of gorilla are now recognised by naturalists. Firstly,
we have the true An(hropopitliccu% gorilla tvpiais, vS
the Gabun, in which the general colour is blackish grey,
frequently with a mixture of reddish brown hair on the
crown of the head; while very old males take on ;i
whitish grey tinge on the upper portion of the thigh
and the lower part of the back. .Secondly, there is
A. g. castaneiceps, which apparently ranges southward
to Portuguese West .Africa, and has longer hair, with
the crown ochre-brown, the back grey, and the limbs
blackish. The third form is A. g. bcringeri, founded
on the skull of a male killed near Mount Kirunga.
south of the .Albert Kdvvard .\yanza. in which the males
are bearded. Finally, A. g. 'dtehli is known onlv by a
skull from the Cameruns.

" Pliysiography " (Macmillan and Co.). by T. H. Hii.xlcv.
This excellent standard work on the introduction to the
Study of Nature has been revised, extended, and to some
extent re-written bv Professor R. A. Gregory, of Queen's
College. London. He has done his work with modesty and
discretion, and the addition of copious illustrations greatly
add both to the usefulness and attractiveness of the book.

CORRESPONDENCE.

Snake Forms irv the Corvstella.tions.

To THE EnlTOKS OF " Knowlkdge."
Gentlemen, — In your issue of October, 1904, Mr. Maunder
writes as follows: " If we take a preccssional globe, move the
pole back some 64° or 65° of precession, corresponding, say,
to about 2700 li.c, and .idjust the globe for N. Lai. 40' — in
other words, set it to the time and place when the constella-
tion figures were first defined — what do we find ? First of all
the Great Dragon . . .

" Next Hydra. Here we have an arrangement even more
striking. As fig. 3 will show, Hydra at this time lay rif;ht
along the equator, extending over about 105', or seven hours
of Right Ascension. Thirdly, Serpens ... It is
scarcely conceivable that this threefold arrangement, which
is not suggested by any natural grouping of the stars, should
have been carried out as a matter of pure accident. It nui.st
have been intentional. For some reason or other— possibly
for the simple one that a snake was the animal form that
best lent itself to such a purpose — tlie equator, the eoliire, the
zenidi and the poles were all marked out by these serpentine
or draconic forms."

Will you allow me space in your columns to re-state an
alternative suggestion made by me, concerning the date of the
first imagining of the constellation Hydra, in a paper entitled,
" .-Vstronomy in the Rig V'eda," read in Rome, October, iSqy,
at the Oriental Congress, and reprinted in my book, "Ancient
Calendars and Constellations."

This suggestion would credit the astronomers of old with a
recognition of the deeper meanings of an almost universal
serpent symbohsm ; and it is, as it appears to me, more in line
with the results of recent archa;ological discoveries which
seem almost necessarily to throw back such symbolism, and
with it the dawn of astronomy, to a date much earlier th.an
2700 H.C.

" On the celestial sphere many serpents and dragons are
represented, but the far-reaching constellation Hydra exceeds
.ill the others in its enormous length from head to tail. No
very brilliant stars mark the asterism, nor in the grouping
of its stars is there anything especially snake-like. For some
reason other than its appeal to the eye did astronomers of old
invest with all the horrors of the Hydra-form the monotonous
length of this space on the vault of the skies.

" This reason may be arrived at, with almost certainty, in
studying, with the help of a precessional globe, the position in
the heavens of this constellation in different ages of the world's
history. So studying, we shall find that 4000 b.c. — or, to be more
precise, one or two hundred years earlier— Hydni extended
its enormous length for more than tjo' symmetrically along
one astronomically important (though invisible) mathematical
line — the line of the heavenly ecpiator— and was at the same
date accurately bisected by another equally importaTit mathe-
matical line, namely the colure of the summer solstice.

" Almost irresistibl v, as it appears to me, the conviction forces
itself on the mind, in considering the position held by the con-
stellation Hydra 4000 n.c., that it was at tliat date that this
baleful figure was first traced in imagination on the sky, there
fitly to represent the power of physical (and may we not
suppose also, of moral ?) darkness— a great and terrible power
— but a power ever and ever again to be conquered by the
victorious power of light. In astronomic myth this power was
represented as that of the sun at the season of its highest cul-
mination, the season of the suimner solstice. For an observer
in the temperate northern zone all through the long nights of
mid winter, the whole length of the dreadful Hydr.i was at
the date named visible above the horizon. The dark mid-
winter season was therefore the time of the Hydra's greatest
glory. At every season of the year, except at that of mid-
summer, some portion of the monster's form was visible
during some part of the night. Hut at tlie summer solstice
no star in the constellation might show itself for ever so short
a time."

I am. Gentlemen, &c..
The Oaks, E.mmeline M. Plunkkt.

Wimbledon Common.

302

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

[The credit belongs to Miss Plunket of having first pointed
out that the Hj'dra was clearly designed by the original
constellation makers to mark the equator celestial, and I
have no doubt that Miss Plunket's suggested reason is quite
correct, namely, that the ancients wished to mark by this
gre;it snake the part of the equator which was furthest below
the track of the sun. And it lay along the equator approxi-
mately both at the date she urges (4000 B.C.) and at that
which I put forward (2700 H.c). Nevertheless the earlier
date is inadmissible. The south pole of 4000 B.C. is too far
from the centre of the unmapped space in the southern
heavens for the work of constellation making to have been
completed by that epoch ; and, as I have elsewhere pointed
out, the traditional figures bear too manifest indications of
being items in a single plan for the work to have been done
piecemeal, or to have occupied several generations. The
earlier date would also displace Serpens and Scorpio from
their very significant relation to the colures. — E. W.\lter
Macndek.]

The Cygnus " CoaLl=Sa.ck,"

To THE Editors of " Knowledge."
Bins, — In the Milky Way, a little north of the "Northern
Cross " — between the stars f and p Cygni, in fact — I have fre-
quently observed a black rift cutting the course of the Via
Lactea transversely. Do you mind explaining the nature of
this phenomenon ?

The appearance does not seem to hv due to the presence of
a dark nebula, because very moderate telescopic aid reveals
faint stars in its recesses.

Have we here a veritable opening in our island-universe — a
sort of tunnel through which we may peer into the sparsely-
lit infinity beyond ?

"^'ours faithfully,
Alderwasley, nr. Wirksworth, J. B. Wallis.

Derbyshire,
November 14, 1904.
[The rift to which Mr. Wallis draws attention is clearly shown
on Dr. C. Easton's charts of '• La Voie Lactee." The
phenomenon is doubtless of the same nature as the other
numerous rifts, channels, and gaps in the Milky Way ; they
cannot be due to the interposition of dark absorbing nebula:-,
but are evidently integral parts of the Galactic structure. —
E. Walte.r Maunder. 1

The TeaLchirvg of tKe Principles
of Evolution in the Schools.

To THE Editors of " Knowledge."
Sirs, — Over a quarter of a century ago Professor Virchow
said: "If the theory of descent is as certain as Professor
Haeckel thinks it is, then we must demand its admission into
the school, and this demand is a necessary one." I think the
time has arrived when all educationists should consider the
desirability of teaching children the principles of evolution. I
believe all the sects accept the evolution theory, and it would
not be difficult to present the facts in such away that children
could understand them.

Yours faithfully,

J. A. Keid.
Kincraig, Cutcliffe Grove, Bedford,
November 18, 1904.

REVIEWS OF BOOKS.

Earthquakes.— If it wore possible to find a peg for criticism
in so admirable a work as M.ijor C. E. Dutton's " Earthquakes
in the Light of the New Seismology" (John Murray), it would
not be in the book but in the fact that the first general digest
of the knowledge and views which are associated with the

work and theories of Professor John Milne, Professor Ewing,
Professor Nagaoko, of Tokio, Major f)e Montessus de Ballore,
and Dr. Emil Rudolph, of Strassburg, should have been made
by an American rather than by an English man of science.
However, science is the true cosmopolitan influence, and it
behoves us to regard Major Dutton's able, patient, and
judicious examination of what the liest authorities think and
know of a subject which has a fascinating interest for all man-
kind, as an iustance of it. A happv distinction is made in
Major Dutton's introduction between the standpoint of the
new seismology and the old. The old view of earthquakes
was that they were one of those formative geologic forces,
almost as mysterious and axiomatic as the occurence of matter
ifself, which existed in order to bring about structural results.
The new view regards earthquakes as merely the effect of
geologic forces, just as thunder is an effect of the electric
discharge — not the cause of it. As a sound is the elastic
vibration of the air, so an earthquake is merely the elastic
vibration of the earth mass. Hence the science becomes
in a great measure the investigation of elastic wave
motion in a solid medium. That investigation became
possible with the invention of the seismograph, the earth-
tremor measurer; and the correlation of the results which the
seismograph afiorded was primarily the work of John Milne.
He has been followed by hosts of patient investigators in every
country of the world ; and Major Dutton's book is a summary of
the results and conclusions at which they have arrived. His
earlier chapters set forth the nature of earthquakes and dis-
cuss their double causation, \olcanic .and "stratagic," if we
may coin a word to replace the usual one of "tectonic."
Chapters descriptive of the instruments used are followed by
others which enter exhaustively into the character, charac-
teristics, and theoretic features of the various kinds of earth
tremors or waves which agitate the earth's mass and the
earth's crust. Chapter XIII. takes up the question of speed
of propagation, its connection with the relation of elasticity to
density; and the light which is consequently thrown on the
densities of the earth's interior at varying depths. The last
chapters indicate the general distribution of earthquakes, and
the index they afford of the points of origin of great seismic
disturbances, both on land and in the depths of the sea. The
volume is one of the most interesting which has appeared in
the " Progressive Science Series," and will appeal to a world-
wide audience.

"The Mathematical Theory of Eclipses," by Koberdean
Buchanan, S.B. (J. B. Lippincott Company, Philadelphia
and London, 1904). This work is designed for the computer
of solar and lunar eclipses, and not for the use of the practical
observer. The author is eminently fitted for his task, as he
has been engaged for the last .;4 years on the computation of
eclipses for the American Ephemeris. The book is based on
Chauvenet's chapter on eclipses in his " Spherical and Prac-
tical Astronomy," but the great experience of Mr. Buchanan
has led him to sift out the unnecessary formula from the neces-
sary, and to arrange their order into a more convenient form
for computation. A graphic method is also employed for
explaining the formulee : — " The eclipse is dissected after the
manner of a surgeon — it is cut up and the hidden parts laid
open to view." Mr. Buchanan observed the total eclipse of
1900, May 28, at Newberry, South Carolina, where he gave
special attention to the shadow bands, and this feature is the
only observational one connected with eclipses with which he
treats. The cause of the shadow bands is still doubtful, but
Mr. Buchanan is inclined to attribute them to the undulations
and disturbances of the density of the atmosphere within the
core of the shadow, caused by the lower temperature of the
cone (which may fall by 4° or 5°), thus producing intermittent
opacity. He also explains the factor producing the " Black
Drop" in a transit of Venus or Mercury, and " Baily's Beads"
at the second and third contacts of the moon with the sun. He
also clearly disposes of the somewhat widely-spread idea that
the darkness at the Crucifixion was caused by an eclipse of
the sun ; this could not be, since a solar eclipse can only occur
at new moon, and the Feast of the Passover (upon the eve of
which the Crucifixion took place) was appointed by the law to
be held at the full moon of the first month.

Chemical Enjiineering. — A second edition of Mr. George E.
Davis's " Handbook of Chemical Engineering " has been pub-
lished by Messrs. Davis Brothers, of Manchester, and the

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

i^3

necessities of enlargement and revision, which arc imposed on
svich a work by the develnpments of modern practice and
scientific investigation of methods, are very liberally complied
with. The ample space of these two volumes, numbering over
a thousand pages and comprising more than five hundred
illustrations, permits of the most complete examination of the
growing requirements of industries which continually show-
expanding necessities and unbounded possibilities. The
volumes, primarily designed for the use of the works manager.
are written with a view to be of interest and instruction to the
student also. This is the more evident in the second volume.
where considerable additions have been made to the theoretical
consideration of questions connected with the absorption and
compression of gases; and to the application of electricity to
the chemical and .allied industries. ()ur space will not permit
us to enter into a detailed examination of Mr. Davis's
standard of theoretical requirement in the information
which he gives on his subjects ; but we may note that in
the chapters relating to gases and to heat the theoretical
side of the questions considered receives treatment which is
equally full and lucid. It will be of greater service both to Mr.
Davis and to intending purchasers of his valuable volumes to
enumerate briefly the new features which have been added to
the second edition. In the chapters dealing with steam and
power, the subject of water softening has been more fully
treated, and the flow of steam through pipes investigated
by the light of the latest information on thi; subject. The
flow of viscous liquids through pipes and the cost of moving
gases by various methods receive a good deal of attention ;
and suction producers, the Diesel engine, and the De Laval
steam turbine are now fully described. The first volume
concludes with a chapter on the treatment and preparation of
solids; the second begins with three chapters on heat and the
compression and absorption of gases to which we have
referred. In connection with the applications of electricity,
the electro- smelting furnaces of Stassano, Heroult, Harmet,
and Kjellin are both described and illustrated. But perhaps
the most important addition to this subject is the information
given relating to the comparatively new industrj' of electro-
magnetic separation, which is very fully described .and illus-
trated. All the various s\'stems of magnetic separation have
been noticed and many figures of separations from actual
practice have been included in the work. Increased attention
has also been given to the subjects of hygiene, and especially
to accidents and to the treatment of cases of gaseous poison-
ing. In this connection, the construction and use of respirators
has secured additional space, which it is hoped will lead to an
extension of knowledge of this important subject.

"The Rob Roy on the Jordan" (John Murray) carries its
thirty and odd years lightly. The present eighth (2s. 6d. net)
edition of Mr. Macgregor's canoe cruise in Palestine, Egypt,
and the waters of Damascus is as fresh as the day it was
written. The most interesting point of a narrative that is full
of interest is Mr. Macgregor's description of his discovery of
the mouth of the Jordan, which " eludes our sight by diving
into jungle, where it defies all search from the north side as to
where its waters roll into this Lake of Nierom." He found it
entering the lake at the end of a promontory of papyrus of
the richest green, and upright as two walls on either hand.
Apart from the intrinsic interest of the matter the naivcli- of
the style lends it additional charm.

Light and Water. — The luxnriousandattr.active volume which
Sir Montague Pollock calls " Light and Water " (George Hell
and Sons) is described by him, in his secondary title, as a Study
of Reflexion and Colour in Kiver, Lake, and Sea. It is, in
fact, an attempt to state the elementary scientific principles
which govern the reflexion of light from water, in such a way
as to be a guide to the artist or art student. The book serves
its purpose admirably; the simpler laws of optics are st
in terms that are comprehensible to the meanest intellige;
and the author's very agreeable style should commend his
book not merely toartists, but to any lover of Nature. Numerous
and beautiful illustrations, especially those accompanying the
chapters on colour in water, have a value .and interest in
themselves.

Physical Science. — We must confess to no great predilection
for works which summarise in a compressed form half a do^en
scientific problems. But an exception must be made in the

instance of " The Recent Development of Physical .Science,"
by W. C. 1). Whctham, I'.R.S. (John Murray), which sets out
thos-j questions of gaseous li(|uel'action, of r.ulio activity, of
atoms, electrons, ions, and the ether, the consideration of
which has become the theme almost of household di.scussions.
Often books of the kind are very loosely scientific, and. in the
attempt to interest, are neglectful of the necessity to instruct.
Hut Mr. Whctham takes a very different view of his res|)onsi-
bihties. He relates the various problems one to the other;
he shows what conunon basis they h.ave ; he compares dis-
covery with theory ; he interprets the philosophical aspect of
scientific ende;ivour in physical science. To his task of inter-
pretation he brings a pen of singular clearness, and a manner
that is graphic, illustrative and succinct. Such an essay may
be comp.ired to the best form of public lecture. It demands
intelligence on the part of the auditor, but its underlying pur-
pose is to direct that intelligence into channels of greater and
more complete information. It would be a very poor compli-
ment to Mr. Whetham to describe his work as popular in the
ordinary sense of the expression, but in the better sense, as a
book of the greatest utility and interest to the educated ]iublic,
it may be so considered.

Sociulogy. Mr. J. Lionel T.ayler's '-Aspect of Social Involu-
tion " (Smith, Llder, and Co.) is a suggestive contribution to
the new science of ICugenics. It has been more than once
pointed out, and that by observers in widely distributed fields
of observ.ition, that the improvement of the race cannot be
scientifically effected by any scheme that our knowledge can
at present propound. There seems, in fact, to be no way of
improving the race better than that which was suggested by
the late K. L. Stevenson in the words that "one person I have
to make good -myself. My duty to my neighbour is better
expressed by saying that I have to make him happy — if I can."
But at the root of happiness and of goodness lies increased
and better knowledge; and in a true appreciation of the diffi-
culties and of the problems is the only hope of the betterment of
the race. It is lor these reasons that such honest efforts as
those of Mr. Tayler to state the problems and the difficulties
are to be welcomed.

Natural History.— There is a great deal of charm about Mr.
Graham Renshaw's "Natural liistory Essays " (Sherrat and
Hughes), which gather together in a convenient form and in a
capitally illustrated book a number of articles on well-known cr
littleanimals, typical examples of the mammalian .African faunai
such as the Harbary Ape, the l-'ennec Eox, the Blue Wilde-
beest, the White Rhinoceros, and that " True Quagga," the
extinction of which, though proved, is constantly denied by
honest but uninstructed hunters of South Africa. A pleasant
gossipy, and withal a sound and valuable book.

Bablngton's Manual of British Botany. — A ninth edition has
been published of the late Professor Habington's " Manual of
British Botany " ((iurney and Jackson), which contains the
flowering plants and ferns arranged according to the natural
orders. The present edition of this useful work, for many
years almost the only critical handbook of British flora, has
been edited by Henry and James Groves, who have included
the notes prepared by its author with a view to a subsequent
edition, together with the results of recent work in botany.

Flowering Plants and Ferns. — .'V second edition in one volume
has .ippeared of Mr. J. C. Willis' useful guide to the students
of botany, " .'\ Manual and Dictionary of the Flowering Plants
and Ferns" (Cambridge University Press). It is in fact a
summary of scientific information about the plants to be
found, either in a botanical garden or in the field, and it
embraces the subjects of morphology, classification, natural
history, and economic botany. It is well adapted both for

!iie study or for work in the country, especially as the
r riptions of genera are not unnecessarily technical.

The Timbers of Commerce. — "The Timbers of Commerce and
their Identilication " (William Rider and Son.s), by Hubert
Stone, I'.L.S., F.R.C.I., consists of an exhaustive tabulation
and characterisation of the various woods used in trade.
Under the heading of each wood is given its botanical classifi-
cation, its source of supply, its physical characteristics, its
uses in commerce, together with its numerous other qualities,
and fine photographs show sections of the principal kinds

304

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

mentioned. In his introduction and chapter on practical
hints Mr. Stone speaks of his subject with l<nowledf;e and
enthusiasm, and it should be a valuable handbook to experts.

Miscella.neous-

Photography. — We have received for review five volumes of
the " Photof,'raphy " Bookshelf series, published by Messrs.
Iliffe and Son at is. They are intended tor practical purposes,
are simply written, and sufficiently illustrated. No. 10,
'■ Practical Retouchins," containing,' hints for after treatment
of the negative by Drinkwatcr Hutt, F.R.P.S., now appears as
a second edition. In No. 15, which deals with " Intensifica-
tion and Reduction," Mr. Henry W. Bennett considers the
methods that experience has proved to be most successful in
the process of stren,t;thenint,' or modifying negatives. Nos.
17 and iS, on " Professional Photot;raphy," by C. H. Hewitt,
contain chapters on such sul>jects as the Back.t,'round, Por-
traiture Outside the Studio, Lii^hting the Features, and Prin-
ciples of Composition. No. 5, " Photography in Colours," by
R. Child Bayley, F.R.P.S., appears as a second edition.

Malabar and Us Folk (Natesan and Company, Madras), by
T. K. Gop.d Panik-Kar, B.A., describes the social customs
and institutions of Malabar. It contains a good deal of curious
and interestint; matter, set forth in a quaintly picturesque
language, of which the following is a typical example : " Fields
laden with heavy corn waving yellow in the tepid breeze, in
which the busy day-labourer, basking in the fierce glare of a
summer sun, now wipes a brow sprinkled over with drops of
honest toil, afford a rare and amusing spectacle. Now chant-
ing his wild notes, now goading and striping the lazy bullocks
plodding through the hardened mead, he adds to the amuse-
ment of the scene."

The Optics of Photography and Photographic Lenses (Whit-
taker and Co. ; price, js. 5d.), by T. Traill Taylor, is published
as a third revised edition, with an additional chapter on
Anastigmatic Lenses, by P. F. Everitt.

The London University Guide, 1905 (University Correspondence
College) rontains regulations for the Examinations to be held
in 1905-6.

The Matriculation Directory (University Correspondence
College, Burlington House, Cambridge) contains the Examina-
tion Calendar for 1904-5, with advice as to subjects and text-
books and specimen papers and answers.

The King's English and How to Write It (Jarrold and Sons), by
John Bygott and A. J. Lawford Jones. — A practical text-book
of essay and pihis writing appears in a sixth revised edition.

Lectures Scientifiques (Rivingtons), by W. G. Hartog, B.A.,
of University College, London, supplies a definite want and is
admirably arranged. Some familiarity with French and
German scientific terms is now essential to all students of
science, and more especially so since the University of London
has prescribed that a candidate for a scientific degree must be
able to read and understand French and German scientific
work. "Lectures Scientifiques" consists of extracts from
modern French scientific writers on the various branches of
science, with a glossary of scientific terms.

One Thousand Objects for the Microscope (Frederick Warne
and Co.}, by M. C Cooke, M..A., gives practical hints for the
use of the microscope, with lists of objects suitable for mount-
ing. It is written in a pleasant, popular style, with numerous
illustrations, and is admirably adapted to the use of the
amateur microscopist.

Private House Electric Lighting (Percival Marshall and
Co.), by Frederick H.Taylor, is a practical popular handbook
designed for the use of the amateur electrician who wishes to
acquaint himself with the best modern methods of the instal-
lation of electric light in private houses. It is useful and com-
prehensive.

First Stage Magnetism and Electricity (University Tutorial
Press), by K. H. Juje, M.,A., D.Sc, appears as a new and
revised edition. It is divided into three parts — I., Electro-
statics ; II., Magnetism; III., Voltaic Electricity — and is
designed to meet the requirements of a young engineer.

First Stage Steam (University Tutorial Press), by J. W.
Hayward, M.Sc.Vict., is intended to meet the requirements
of the Board of Education examination. It includes examples
of examination papers from igoi to 1904, and sugges-
tions for simple experiments, and is illustrated by numerous
useful diagrams.

Modern Philosophers and the " Per Quem " (Elliot Stock), by
George Edward Tarner, is a conscientious attempt to re-affirm
the doctrinal tenets of Christianity, somewhat on the lines of
Patey's " Evidences."

The Seven Lamps of Architecture is published by Mr. George
Allen in one volume at js. 6d. among his reprints of Ruskin's
works. This charming little edition is strongly bound, well
printed, and beautifully illustrated. Ruf kin lovers will gladly
avail themselves of this opportunity of obtaining his works at
so low a price.

The Museums Journal (Vol. III., Dulau and Company), edited
by E. Howarth, forms a useful book of reference, and a com-
pendium of information about museums at home and abroad,
while its numerous illustrations afford interesting opportunities
of comparing the methods of arranging and exhibiting speci-
mens in l-'nglish and foreign museums.

The Reliquary and Illustrated ArchiEologist (Bemrose and
Sons), Vol. X., is a delightful possession. Among many of
its interesting and elaborately-illustrated articles are " Notes
on a Roman Hydraulus." "The Evolution of the Mitre," and
" Medallic Portraits of Christ."

We have also received Part VI. of Messrs. Hall and Steven's
"School Geometry" (Macmillan), the general principles of
the methods of which have already received favourable notice
in our columns; and " Elementary Plane Geometry " (Blackie
and Son), by Mr. V. M. Turnbull, which proceeds on the
Cambridge method of following up the experimental work of
measuremetit and calculation with deductive geometry.

We have received from Mr. John Murray Professor W. H.
Pickering's monograph on " The Moon," and Dr. George
Newman's " Bacteriology and the Public Health," both of
which will be fully noticed in our columns next month. We
have also received for review " Light Energy," by Miss
Margaret A. Cleaves (Rebman. Limited), which will also be
further noticed.

We have also received " Eton Nature Study," by M. I). Hill
and W. Mark Webb (Duckworth and Co.) — a book which has
every title to attain its desired aim of inculcating the teaching
of natural history and botany in schools; and " Nature Teach-
ing," by Francis Walts and W. G. Freeman (John Murray),
which aims at teaching botany to the schoolboy from an agri-
cultural and horticultural standpoint. It is excellent alike in
aim and plan.

Messrs. Darton's Electrical Novelties. — We have received
Messrs. Darton's new catalogue of electrical novelties. The
novelties are chiefly of the kind associated with the many uses
to which electricity, with its great capacity for sub-division,
can be put in the household and the laboratory. The small
motors are specially adaptable to such uses ; the dynamos and
small gas-engines are susceptible of application to larger pur-
poses. Besides these, there are the many varieties of electric
lamps with light dry cells which can be used for bedside illu-
mination, for bicycles, or for railway travelling ; accumulators
for motor-car ignition; electric bells and their accessories;
house telephones; medical magnetic coils; induction coils,
and other devices of an analogous character.

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

305

A Microphotograph of Fossil CoqlI.

THEaccompanyinff Microphoto-raph of Fosiil Coal is one of those with-which Mr.Thos E. Freshwater, F.K.M.S., F.K.P.S.,
won ri.re? Medal this year at"the St. Louis International Exhibitio,,, and ,s re,,roduced|by h.s '^""^^'-"^^ P^;"";;^'""- .^f;
coal of which it is a photograph occurs at Beith, in Scotland; and the photograph was. taken on an Ilford ordin.ir> plate,
with a Zeiss Planar lens, 2oni/m. focus ; at an angle of 65 deg.,and with a 24-mch extension of the camera.

3o6

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

Conducted hy F. Shillingtox Scales, f.r.m s

Royal Microscopical Society.

At a meeting held on October 19 at 20, Hanover
Square, Dr. Dukinfield H. Scott, F.R.S., President, in
the chair, Mr. Rousselet described a Lucernal micro-
scope, further portions of which had been presented by
Mr. Orfeur. The instrument bore no maker's name,
but was built on .Adams' model and was probably of a
rather later date than his time. .A description of this
maker's " Improved and Universal Lucernal Micro-
scope " will be found in Adams' Essays on the Micro-
scope, 1787. The Secretary called attention to
micro-photographic portraits of Prof. Quekett and two
others who were unnamed, but which were identified
as being likenesses of Dr. Letheby and Dr. John
Millar. A communication from Mr. \V. D. Colver
was read describing the antenna of Pnhx irritans, on
the terminal joint of which Mr. Wm. Jenkinson, of
Sheffield, had discovered a lamellated structure which
he believed to have an olfactory function. Mr. Jenkin-
son had found similar structures in several other mem-
bers of the family of the Pulicidas. A slide showing
the entire antenna, and another showing the terminal
joint, were exhibited under microscopes, and photo-
graphs of the latter slide were also exhibited in the
room and on the screen. Part xvii., the concluding
part of Mr. Millett's Report on the Recent Foramini-
fera of the Malay Archipelago, was taken as read, and
will be duly published in the Society's journal. The
President then gave a demonstration "on " The Recon-
struction of a Fossil Plant." The plant selected was
Lygmodendron Oldhamium, and the growth of our
knowledge of its structure was illustrated by actual
sections and lantern slides shown on the screen. The
identification of the stem of a Pinites, the fern-like
petiole of Rachndpteris asfcra, and the foliage of
Spkenopferis Honinghausi as being corresponding parts
of Lyginodendron was demonstrated. It was dis-
covered that the stem was frequently branched, and
certain fossil .seeds are now, on structural evidence and
association, considered to be the fruit of this plant.
The reconstruction of the plant is, however, still in-
complete, as the male organs have not yet been identi-
fied with certainty. The position of Lvginodendron
as a seed-bearing plant allied at once to Cvcads and
Ferns was now established. A picture of die recon-
structed plant was shown on the screen, and models of
the seed, kindly lent bv Prof. F. W. Oliver, were
exhibited.

The Quekett Microscopical Club.

The 416th ordinary meeting of the Club was held
on October 21 at 20, Hanover Square, W. There was
an unusually large alfendanre of members, and the
long list of new members prf)posed for election gave
proof of the strong position held bv the Club which
will shortly celebrate its fortieth anniversary

Messrs. W. Watson and Sons exhibited their latest
designs and models, both of microscopes and
apparatus, together with some very fine slides, princi-
pallv of marine life.

I\ir. F. P. Smith gave a very interesting lecture on
the "Spiders of the Erigone group." He described
at some length the most striking feature of the sub-
Family, viz., the extraordinary formation of the caput
in the males. In this sex the caput is almost always
of a form different from that of the females, being, as
a rule, more or less raised. It was generally thought
that such elevation of the caput was intended to extend
the field of view, but this seemed doubtful, as the eyes
which were placed at the top of the elevation were
sometimes so feebly developed that they would gain
little or nothing from such elevation. In other species
again the eyes were not placed on the summit of the
elevation, and in some the elevation was so placed as
to obstruct the field of view.

Mr. Smith then dealt with the classification of the
grouo, suggesting a re-arrangement of certain genera
and the creation of two new genera for existing species.

Two very old members of the Club, both well known
in the microsconical world, have passed away during
the last month.

C. G. Dunning joined the Quekett Club in October,
187J, and was on the Committee from 1876 to 1879.
He died on September 29. Being of a mechanical turn
of mind, he devoted himself to the improvement of
microscopical accessories, and invented an improved
form of turntable, a portable microscope lamp, and a
trough, all of which bore his name, and were in de-
mand in their time, though now superseded by later
models.

Edward Dadswell, F.R.M.S., joined the Club in
January, 187s, and with the exception of one year,
1882, he served continuously on the Committee from
1879 to 1903. As one of the most familiar figures at
the Club, and prominent in its social life and
excursions, he will be greatly missed, although he had
not been able to attend for more than a vear previous
to his death. He died on October 6, and the interest
which he had always displayed in the Club is marked
hy a legfacy of ^^30, which he has bequeathed to it in
his will.

Staining and Preserving Algae.

J. Q. T. writes from Queensland giving the following
particulars of a method of staining and preserving
alga;, which he has found very satisfactory. The re-
agents required are made up as follows : — Fixing
solution: Chromic acid, i oz. ; glacial acetic acid, 4 oz. ;
formaldehyde as formalin (Schering's), 4 oz. Pre-
serving fluids : Best glycerine, 8 ozs.; glycerine jelly,

1 oz. Chromo-aceiic acid: Chromic acid, i gramme;
acetic acid, i cc. ; water, 100 cc. Formalin {4 per
cent.); Schering's formalin, 10 cc. ; water, 90 cc. (for a

2 per cent, solution take half the quantity of formalin).
Stains: — Tlaemaluni (Griibler); Hacmatoxylin solution:
Haematoxylin cryst. puriss., i gramme; water, 200 cc.
Iron alum solution: Iron alum, 3 grammes; water,
100 cc. (The iron alum should lie in pale violet
crystals, not yellow or green, and should be kept in an
air-tight tube.) Eosin solution (water soluble) : Eosin,
I gramme; water 200 cc.

The material, which may be " fruiting " or sterile,
is gathered in jars and brought home in water, or can
be placed directly in the fixing solution at the time of

Dec, 1904.]

KNOWLEDGE & SCIENTIFIC NEWS.

307

•j.itliei iiit;, this last being generally preferable. If
fixed in the chromo-acotic mixture it will require about
twelve hours for thorough fixation, and twenty-four
hours in the formalin. .After chromic acid, the material
must be washed in running water or frequent changes
for at least one hour, or, better, for three hours. The
following simple little piece of apparatus is very useful
for washing. It consists of a test-lube fitted with a
cork, through which two pieces of glass-tube p.iss.
One of these is connected to a water-tap by a piece of
rubber tubing, which, in turn, is connected to a piece
of glass tubing passing through a cork jammed in the
mouth of the tap. .V piece of thin muslin is tied over
the end of the other tube inside the jar to prevent the
escape of specimens. With formalin no washing is
necessary.

The material being fixed, the next C|uesti()n is the
stain. If nuclei are the only details required,
Haemalum will be the best to use. It should either be
used strong for fi\e minutes, or diluted (i cc. to 50 cc.
of water) for twenty-four hours. The staining must
be carefullv watched in both cases. Overstaining may
be remedied bv water acidulated (.1 per cent.) with
hydrochloric acid, but the method is somewhat risky.
The other methods of staining are as follow : — .Stain
with iron alum solution for three hours, wash in
running water for one hour. Stain in Hacmatoxylin
solution for six to twelve hours. Now comes the
delicate part, for the tissues are much overstained,
and must be washed in the iron solution till the details
are brought out, examining with the microscope the
whole time. Immediately the details are out (gener-
ally in about a quartcr-of-an-hour), the decolourisation
is stopped by placing the object in tap or rain water.
\ow place some water in a watch-glass and add 5 per
cent, of glycerine. Transfer the algfe to the dilute
glycerine and cover it with an inverted watch-glass,
to prevent dust without checking evaporation.
Leave until the glycerine is thick enough for
mounting, mount in a shallow tin cell in just enough
glycerine to fill the cell (this requires some practice),
seal with gold size, and when dry ring with Brunswick
Black. In some cases a contrast stain may be de-
sired. This can be obtained by placing the tissue in
the eosin solution for 30 seconds or less, pre\ious to the
transference to the 5 per cent, glycerine.

Notes and Queries.

Resolution of Amphlpleura peilucida.

Mr. C. Mostyn (of Kamsgate) writes: Your paragraph in
" Knowledge " on resolving .Aniphipleura induces me to
describe a method I have lately hit upon, which may possibly
not be known to all microscopists. It has the merit of extreme
simplicity, not even requiring a sub-stage condenser, or, in
fact, any extra appliance whatever, except a sutTicientlv power-
ful source of light, and giving the most brilliant resolution
("false resolution," so called, of course) that I have ever
obtained, even with immersions and condensers of great N.A.
It happens that my microscope (a " Star ") has the very useful
fitting of a mirror that can be swung up above the stage for
opaque objects. It occurred to me to experiment in the direc-
tion of obtaining a " dark ground " or " opaque " illumination
with high powers, preferably immersions, by concentrating
light on the film of immersion fluid. I tried, among other ex-
periments, a slide of Angulatum, mounted in realgar, with a
y/' water immersion. N..\. fi8, and sunlight. The result was
the most beautiful exhibition of the diatom I have ever seen.

The diatom, by a httlc c.u'eful handlin.i^ul tlu' uiinur, aijpiaied
of a brilliant emerald colour on an ink-black grounil or a
light ground could be had at will — and with excellent definition
and resolution, free from fog or dilfraction etlcct. This success
induced me to try upon Amphiplour.i and Frustulia Saxonica,
both of which were most brilliantly resolved. I fancied I
could, on some valves, detect the longitudinal stri:c of Amphl-
pleura as well ; but the want of a rotation to the stage pre-
vented me from examining the valves in the best manner. I
may add that the objectives, with a dry condenser of N.A. fo,
had hitlierto failed to give resolution, try as I would, with or
witliout stops, though an oil lens of N..\. i'25 would do it easily.
I then tried a /^eiss ._,'„" — an old water-lens, whose N.A. does
not, I think, exceed no — and it resolved Amphipleura etpially
well. I have seen m.any expert hands take halfan-hour to
effect a satisfactory display ; a minute or two is the outside
required with my plan, given a sutlicient amount ol light, .^n
ordinary microscope lamp, with halfincli wick, is not powerful
enough. Of course, a bull's-eye can be used instead of a
mirror ; but it is not nearly as easy to manage.

I have been told that mine is merely a re-discovery of the
" Bramhall Illuminator," but that was a slip ot looking-glass
placed below the slide, and on a dilferent principle altogether,
though, I believe, very effective in the preimmersion days. I
shut off all light from below the slide altogether, with a closed
iris.

Galls on Oak-leaves. //. 11'. Wntuii, llitinhii'iirth.

The brown gall on the oak-leaf you sent is aCynipidgall,
th^l oi Nciiyotfrus Icnticiiltifis. The gall appears in July and
matures in September, falling to tlio ground about the
cud of that month or the beginning of (October. This autumn
generation is parthenogenetic, but another and a sexual
generation appears in the spring in quite (lilfer('nt spherical
galls known as Spatluxtistcr baccarnm. The gall on the midrib
of the same leaf is Ntui-otenis osti-ciis, whilst the gall with a
depressed centre on the other oak leaf is Sturi)ieriis numis-
inatis, which matures with N. Icntituhiris. These and many
other galls were exhibted by Mr. V.. R. Hurdon, of Sidney
Sussex College, at the last meeting of the 15rilish Association
held in Cambridge, and Mr. Hurdon has been good enough
to name the above species for me. Vou will find the sul)ject
dealt with in " Alternating generations; a biological study of
oak-galls and gall-flies," by Hennaini Adler, translated by
C. R. Straton, and published by tlie Clarendon Press in 1894.
In this book you will find instructions as to rearing the flics — •
the eggs themselves can be easily dissected out if you wish to
do so. I do not think you could turn your attention to a more
interesting branch of study or one offering more opportunities
for original work, as the whole subject has been neglected by
all but a very few workers.

John Hume, Ncwcastkon-Tync. The gall you sent is that of
Neuroterus Iciiticularis mentioned above.

//. 11'. Harvey, Norfolk. What you thought to be a fungus
is the same gall. With regard to the •' second sting" you
speak of, the drawing you send is not sufficient to enable me
to pronounce an opinion, but these stings are generally made
of a couple of darts which join together so as to form a canal
down which the poison passes into the wound. Is it not
possible that you have split one of these, or even damaged
their sheath, and so formed an erroneous impression ?

Derivation of Names of Diatoms.

Rev. W. Hamilton Gordon, of Fareham, Hants, would be
glad if any reader could give the derivation of the names
Sitrirella and Nil:ssihitt as .applied to diatoms. I think there
can be no doubt th.it the latter diatom was named after the
worm of the same name, but that does not bring one much
nearer. With regard to the distribution of diatom material,
I am dependent entirely on the generosity of such readers of
my notes as have material of one sort or another which they
are good enough to send me for distribution to others.

[Communicationi and enquiries, nn Muroscoficiil matters are invittd,
and shuuld lie addressed to F. ShiUini^lun Scales, "Jersey, "St.
Barnabas Road, Cambridge.}

3o8

KNOWLEDGE & SCIENTIFIC NEWS.

[Dec, 1904.

The Face of the Sky for December.

By W. Shackleton, F.R.A.S.

The Sun. — On the ist the Sun rises at 7.45, and sets
3-t 3-53 ! on the 31st he rises at 8.S, and sets at 3.58.

Winter commences on the 22nd, when the sun enters
the sign of Capricorn at 6 a.m. Solar activity is well
marked, and sunspots, faculae, and prominences may be
observed on any favourable occasion.

For physical observations of the sun the following
ephemeris may be used : —

Date.

Axis inclined from N.
point.

Centre of disc, N or
S of Sun's equator.

Dec, I ..
,, II ..
>. 21 ..
,. 31 •■

16^ 6' E.
11° 56' E.

7° 19' E.

2° 30' E.

o" 38' N
0° 38' S
i°54'S
3° 6'S

The Moon : —

Date.

Ptiases.

H. M.

Dec. 7 ..
,. 14 ••
• > 22 . .
.. 29 ..

C New Moon
D First Quarter
0 Full Moon
d Last Quarter

3 46 a.m.

10 7 p.m.

5 I p m.

3 46 p.m.

OCCULTATIONS.-

Star's
Nam 3.

Disappearance.

Reappearance

Date.

Mean
Tniie.

Angle from

Mean
Time.

Angle from

N
point

Ver-
tex.

point

Ver-
tex.

p.m.

p m.

Dec. 20. .

y Tauri

3'9

6.1

130'

7 +

239- ; 275^

„ 20- .

9 Tauri

3-9

11.25
a.m.

M3"

130

a.m.

195' 173"

,. 21..

a Tauri

5-19

57"

17'

4.12

295^ 255"

The Planets. — Mercury is an evening star in Sagit-
tarius, setting about an hour after the Sun until the 25th ;
he attains his greatest easterly elongation of 20-' 30' on
the 14th. The planet is in inferior conjunction with the
Sun on the 31st.

Venus is rapidly coming into a more favourable posi-
tion, and towards the end of the month is well visible
in the evenings. On the ist she sets about 6.15 p.m.,
and on the 31st about 7.45 p.m. The apparent diameter
of the planet is increasing, being 15" on the 15th, whilst
0-75 of the disc is illuminated.

Mars is a morning star in \'irgo, rising about 1.38 a.m.
on the 15th.

Saturn is getting more to the west and also diminish-
ing in brightness. About the middle of the month the
planet is on the meridian at sunset, and sets about 8.15
p.m. The ring is widely open, the diameters of the major
and minor axis of the outer ring being 37"-i and 9"-7 respec-
tively, whilst the polar diameter of the ball is i4"'8.

Uranus is unobservable, being in conjunction with the
Sun on the 22nd.

Neptune rises about 9 p.m. near the middle of the
month. He is situated about 14 mins. east of the
star n Geminorum, as will be seen on reference to the
chart given in the January number. The planet is
in opposition on the 28th, hence al)out this time he
souths near midnight.

Jupiter is in a very favourable position for observa-
tion in the early evenings, being on the meridian about
8 p.m. near the middle ot the month ; also throughout the
month he is visible from sunset until early morning.

The equatorial diameter of the planet on the 15th is
45", whilst the polar diameter is 2"-g smaller.

The configurations of the satellites, as seen in an in-
verting telescope at 9 p.m., are as follows : —

Diy.

West.

East.

Day.

West.

East.

1O324

3O124

312O4

3-'i04

32O14

C 1O24

e 0J2

O1234

41O23

• 2O43

42O13

12O43

• 41O3

43O12

4312O

43?0

432O1

432 0 1

413O2

• 41O2

4O123

4 023

• 4203

2'Ji3

4^.03

• 1O34

^Ol2

3104

The circle (O) represents Jupiter ; 0 signifies that the satellite is
on the disc ; • signifies that tiie satellite is behind the disc, or in
the shadow. The numbers are the numbers of the satellites.

Meteors : —

The principal shower of meteors during the inonth is
the Geminids, December loth to 12th; the radiant is in
R. A. VIII.'' 12'", Dec. -|- 33". The meteors are short
and quick, and difficult to record accurately.

Encke's Comet was again photographed by Max Wolf
on October 28, when its magnitude was 12-5.

The coinet is increasmg in brightness, being in peri-
helion on Jan. 4, hence it should be visible in ordinary
telescopes early in the month ; after the first few days,
however, the Moon and the comet's motion into daylight
will make observation impossible.

The following ephemeris is for Berlin noon.

Date.

ght

Ascension.

Declination.

(

Dec. I

+ 9

35 I

,.2

o-o

..3

246

,,4

489

,, 5

5«

+ 7

130

Minima of Algol may be observed on the ist at 10.22
p.m., on the 4th at 7.1 1 p.m., 7th at 4.0 p.in., 22nd at
0.5 a.m., 24th at 8.54 p.m., and 27th at 5.43 p.m.

Telescopic Objects: —

Double Stars: — i Pegasi XXI^ 17.5"', N.u/ 20',
mags. 4-5, 8-6; separation 36"-2.

N. 33"-ii', mags. 4-0, a-o ;
•17', mags. 37, 47; separa-
IV. 29°5o' ; mags. 5, 6'4; separa-

T Andromedae o'^ 31.5
separation 36"'3.

a Piscium P 56 9", N.
tion, 3"-6

iTrianguli II^ 6.6"
tion 3"-5.

Clusters: — (^ vi. 33, 34). The Perseus clusters
visible to naked eye and situated about midway between
7 Persei and 5 Cassiopeiae. These magnificent clusters
are described by Smyth as " affording together one of the
most brilliant telescopic objects in the hea\-ens."

Q Knowledrre

Applied iJci.
Serials

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CARDS OR SLIPS FROM THIS POCKET

UNIVERSITY OF TORONTO LIBRARY

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

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