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With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
CONDUCTED BY
Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
Let Knowledge grow from more to more."
— Tennyson.
Volume XXXVI,
New Series, Volume X.
1913.
London ;
Knowledge Publishing Company, Limited,
42, Bloomsbury Square, W.C.
SEP 27 1968
5&^/ry of to«2*^
INDEX.
ACHROMATIC CONDENSER and its
use as an apertometer, The Aplanatic
and, 310
Adams, Lionel E., 25, 70, 150
" Adon " telephoto lenses, 107
Aeroplanes and weather, 387 s3
Agama, Habits of the, 394
Air, Winds in the free, 269
Alexander, P. J., 453
Albedoes and brightness of the Planets,
The, 17
Albert, The Planet, 306
Alchemical Society, The, 114, 450
Alcohol as a motor fuel, Use of, 182
Alga, A rare, 101
Algae as rock-formers, Calcareous, 430
— ■ — , Evolution among lowly forms, The,
201
Alkaline water on lead, Action of, 463
Alkaloids in plants, The formation of, 463
Allen, Immo S., 373
Amateurs, Stellar photography for, 449
America, Early man in South, 347
Amphibian skin, Poison of, 435
Analysis, Luminescence, 100
Andromeda Nebula, Parallax of the, 264
, The, 461
Angiosperms, Recent research on embryo-
logy of, 383, 426
Animal life of Blakeney Point, Some notes
on the, 132
Animals, Hairs of, 283
, Manganese in, 187
Anlacodiscus kittonii — An apology, 433
Announcements, 213
Antarctic Echinoderms, Parental care
among, 67
Lichens, 265
Antoniadi, E. M., 193, 288
Ants and caterpillars, Commensalism of,
392
Apertometer, The aplanatic and achro-
matic condenser and its use as an, 310
Aperture to power in the microscope
objective, On the relation of, 63, 102,
148, 189
Aplanatic and achromatic condenser and
its use as an apertometer, The, 310
Apparatus, A new photo-micrographic,349
Argentine, Oven birds in the, 149
Argon and its place in Nature, 307
Arran, A Riebeckite rock from, 146
Arsine, Micro-organisms producing, 463
Asama-Yama (Japan), The recent erup-
tions of the, 94
Ashton, Percival J., 334
Astronomy Notes, 17, 59, 97, 143, 179,
217, 264, 305, 344, 383, 425, 460
, The new, 114, 243
Atkinson, A., 288
Atlantic, January, 1913, Storms on the,
220
Atom, The birth of an, 145
Atomic weight of Chlorine, 464
Atmospheric turbidity of 1912, 269
Auroral expedition to Bossekop in the
spring of 1913, On an, 263
Australia, Discovery of a Comet in South,
179
Australia, Land crayfishes of, 393
Australites, 308, 409
Auxetic action on spores of a new species of
Polytoma, 109
Azolla, Massulae of, 18
BACTERIA AND FUNGI, LUMINOUS,
98
, Cytology of, 307
Bacterial nodules on leaves, 306
Bacteriology, Electrical conductivity in
the service of, 204
Bacterium, A new iron, 266
Barnett, H. Norman, 253
Barograph Record, A, 68
Barometer, Garnet as a geological, 386
records, Lowest, 221
Bat's wing, Accessory cartilage in, 353
Bauxites of North-East Ireland, Iron-
ores and, 101
Beach, The Shingle, 1
Beaches and palaeolithic man, Raised,
220
Bedrock, 332
Bee, The red-tailed humble, 161
Bees, Colour sense in, 152
, Hermaphrodite, 392
Beetle, The cigarette, 314
Beetles and Orthoptera, Gizzard in, 276
Bellamy, F. A., 293, 334, 421
Belts on Neptune, 265
Ben Nevis Observatory, 386
Benham, Charles E., 163
Benn, Alfred W., 459
Bennett, The Rev. F., 47
Bickerton, Professor A. W., 407, 441
Biogeography of the Atlantic Isles, 267
Biological enquiry, An unbiased, 205
Biology of desert plants, 59
submerged water plants, 345
the pitcher plant Dischidia, 307
Bird-calling, 173
Birds assuming the plumage of the male
bird, Hen, 189, 288
in the Argentine, Oven, 149
, Perching in, 187
, The Committee for the Economic
preservation of, 274
, existence of luminous, 321
, recovery of marked, 24
Blake, A. G„ 242
Blakeney Point, Some notes on the animal
life of, 132
Blathwayt, Theodore B., 298
Bolivia and Peru, Natural History notes
from, 152
Boron, Hybrids of, 145
Bossekop in the spring of 1913, On an
Auroral expedition to, 263
Botany at the British Association, 383,
1(12
, Dark-ground illumination and ultra-
microscopic methods in, 361
Botany Notes, 18, 59, 98, 144, 180, 218,
265, 306, 345, 383, 426, 462
Boys' rainbow cup, Professor, 115
Brierley, Harwood, 175
Britain, Negro man in, 123
British Association, Botany at the, 383,
462
, Chemistry at the, 21, 429
, Section G, 464
Bug, A marine, 354
Bugs, Geographical distribution of bed,
354
Bulman, G. W., 161, 212, 281
Burke, John Butler, 373
Burton, James, 62, 102, 466
Butterfield, W. Ruskin, 299
Butterflies, A detail in the protective
colouration of, 47
CABBAGE FLEA, VINDICATION OF
THE, 26
Cairns, J. E., 154
Calcareous algae as rock-formers, 430
Calcite crystals from a water-tank, 464
Cameras, Fixed focus, 186
Campbell's " Stellar Motions," and Sir
David Gill's " History of the Cape
Observatory," 461
Canaries, The establishment of a race of
white, 401
Cape Observatory," Campbell's " Stellar
Motions," and Sir David Gill's
" History of the, 461
Carbon black, The manufacture of, 101
Tetra-iodide, 307
Carp, A mouthless, 152
Cartilage in bat's wing, Accessory, 353
Catalepsy in Phasmidae, 333
Caterpillars, Commensalism of ants and,
392
Cave spiders, 276
Cavers, Professor, 18, 59, 98, 144, 180,
218, 265, 306, 345, 383, 426, 462
Cell structure and function, Modern con-
ception of, 8
Celts and their manufacture, Polished,
210
Cephalopods, Remarkable blind, 468
Chaetopterus tubes, Commensal crustaceans
in, 468
Chambers, W. F. D., 378
Chemistry at the British Association, 21,
429
Notes, 21, 60, 100, 145, 182, 219,
266, 307, 346, 384, 428, 463
— — of the forest, The, 367
silkworm, 353
Chin, The story of the, 410
Chlorides by sodium, Reduction of metal-
lic, 100
Chlorine, Atomic weight of. 464
Chrysanthemum, Ray florets in the disc of,
409
INDEX.
Cigarette beetle, The, 314
Cinematograph pictures with the micro
scope, Taking, 105
Circle, Squaring the, 67
, Quadrature of the, 249
Clancey, J. C, 51
Claremont, Leopold, 124
Clays, The odour of, 61
Climate and health, 310
change and woodland succession,
218
Climatic changes, Volcanic dust and,
433
Cloud forms, Hourly observations of,
269
, The velo, 349
Clouds, Violent uprushes in cumulus,
221
Clusters and nebulae, Distribution of,
461
Coal, Absorption of oxygen by, 463
, The microscopic examination of,
347
Coalfield of Yorkshire and Nottingham-
shire, The concealed, 268
Cock, A hen ostrich with plumage of a, 7
Coelenterata, Largest and stateliest of
British, 314
Colouration of butterflies, A detail in the
protective, 47
Colour sense in bees, 152
Colours and their changes at sunset on a
tropical island, 54
Columns, Experiments on liquid drops,
globules, and, 52, 121
, Liquid, 121
Comet, A new, 383
in South Australia, Discovery of a,
179
, Schaumasse's, 265
, The orbit of Schaumasse's new, 218
, Westphal's, 425
Comets, 233, 461
Commensalism of ants and caterpillars,
392
Condenser, An aplanatic and achromatic,
270
and its use as an apertometer, The
aplanatic and achromatic, 310
tubes, Corrosion of, 429, 464
Congratulations, 265
Conjugation, Fertilisation and, 276
Contact, The power of, 163
Conversazione, The Royal Society's, 224
Copepod, A hydroid epizoic on a parasitic,
354
Copper sulphate for purifying water, Use
of, 101
Correction, 350
Correspondence, 51, 67, 93, 108, 114, 155,
188, 238, 249, 252. 288, 293, 298, 317,
334, 409, 438, 458, 460
Corrosion of condenser tubes, 429
Cosmological hypotheses, 369
Cow in harness together, A horse and, 138
Crab and its borrowed shell, The hermit,
353
Crabs, Fiddler, 107
Crayfishes of Australia, Land, 393
Crocodiles' eggs, Hatching of, 394
Crommelin, A. C. D., 17, 28, 57, 59, 97,
112, 139, 143, 177, 179, 217, 225, 250,
264, 303, 305, 344, 355, 381, 383,
425, 436, 457, 460
Crustaceans in Chaetopterus tubes, Com-
mensal, 468
Crystals and X-rays, 185
from a water-tank, Calcite, 464
Ctenophores, 26
Cuckoo, The, 24
Cumulus clouds, Violent uprushes in, 221
Curator, A provincial, 15, 155
Cyclone, Hurricane, typhoon, and, 309
Cytisus adami, The graft hybrid, 145
Cytology of bacteria, 307
DARK-GROUND ILLUMINATION, 148
illuminator, A, 102
Darling, Chas. R., 52, 121
Dartmoor, Geology of, 101
Davison, Charles, 94
Deities of ancient Maoriland, The, 454
De Mello, C. H, 189
Dendromonas virqaria Weisse, 466
Dennett, Frank C, 27, 69, 108, 143, 188,
196, 227, 260, 314, 340, 394, 438, 460
Denning, W. F., 240
Desert, An English, 268
plants, Biology of, 59
De Sibour, Count L., 321
Discharges, Silent, 26
Dischidia, Biology of the pitcher plant,
307
Disinfectants, The testing of, 308
Doctor," " The, 309
Dog, Sagacity of a, 368
Downs and their dry valleys, The stream-
less, 281
Drew, Aubrey H., 109
Dungate, E. J., 459
Dust and climatic changes, Volcanic, 433
explosions, 385
Dynamics of pianoforte touch," " The, 186
EARTH MOVEMENTS AND ISOSTASY,
TOPOGRAPHY, 308
Earthquakes from a Japanese point of
view, 167
Earth, The age of the, 294
Earwig, Proportions of sexes in, 67
Echidna, Fungus growing on hair of, 276
Echinoderms, Parental care among Ant-
arctic, 67
Eclipse of the sun, 1913, September 29th,
The partial, 459
Eclipses, Solar, 59
Ecological Society, A proposed British, 56
Ecology, The Journal of, 156
Editorial, 241
Egerton, Alfred C. G., 25, 151, 186, 224,
275, 313, 435, 467
Eggar, W. D., 81
Eggs, Hatching of crocodiles', 394
Egypt, Thunderstorms in, 433
Embryology of angiosperms, Recent re-
search on, 383, 426
Emerald mines, Prehistoric, 124
Engineering and metallurgical chemistry
notes, 429, 464
English desert, An, 268
Eros, The light variation of, 305
Evolution of the Stereoscope, The modern,
327
Exploration, 347
Explorers, Great, 268
Explosions, Dust, 385
Eyes, The Scallop's, 152
FAIRY SHRIMPS, BEHAVIOUR OF,
435
Fan formations, Alluvial, 348
Fats, The hardening of, 21
Fauna of British India, African element
in freshwater, 393
Feldman, Victor, 322
Felspar, The fixation of nitrogen by, 463
" Fernley " self-recording rain gauge. The,
348
Fertilisation and conjugation, 276
Fibres, Action of ozone on, 346
Films of liquid, Stretched, 115
Filoplumes, 27
Filters, Testing dark-room light, 223
Fiords, 464
Fish, A remarkable, 392
, Extraordinary mode in parental
care in a, 353
Fishery research and Meteorology, 433
Fishes, Climbing, 221
, Colour of, 67
, Inflation in, 276
Fitzsimons, F. W., 7
Fixing, Imperfect, 222
Flashes, Lightning, 438
Flea, Vindication of the cabbage, 26
Flicker, 26
Floral blue, On the, 153
Florets in the disc of Chrysanthemum, Ray,
409
of composite flowers, Phyllotaxis and
the discal, 188
Flowers, Heterostyled, 98
, Phyllotaxis and the discal florets of
composite, 188
Folk Museum, A plea for a British, 299
Foods, On cooked, 68
Foraminifera as world-builders, 354
Forest, The chemistry of the, 367
Formaldehyde in plants, Occurrence of,
267
Fourth dimension and its bearing on the
cause of universal gravitation, The,
242
, The, 67, 68, 93, 108, 155, 239, 252
Fowler's discovery of a new series of
lines in the spectrum of hydrogen.
Professor, 18
Freshwater fauna of British India, African
element in, 393
Fruits, The artificial ripening of, 300
Fungi, Luminous bacteria and, 98
Fungus, A " Domestic," 62
, An explosive, 453
growing on hair of Echidna, 276
GALL PRODUCTION, 393
Gamasoidea, 311
Ganymede, 1911, August 13th, The
occultation of the Star Mayer 588 by
Jupiter's third satellite, 97
Garnet as a geological barometer, 386
Garrard, G. E., 149
Gases from oilfields, Poisonous, 100
Gaubert, A., 68
Gauge,' A sensitive pressure, 435
Gelatin, Imitation pearls from, 267
Geographical Conference, Tenth Inter-
national, 347
Geography Notes, 267, 308, 347, 385, 429
464
Geological barometer, Garnet as a, 386
Geology, Land classification and, 465
Notes, 22, 61, 101, 146, 183, 219,
268, 308, 347, 386, 430, 464
of Dartmoor, 101
the Lizard and Meneage, 22
Geoma, 249
Germany in 1911 and 1913, The flowering
of plants in South, 458
Gill's " History of the Cape Observatory,"
Campbell's " Stellar Motions," and
Sir David, 461
Gizzard of beetles and orthoptera, 276
Glaciers, Studies in, 385
Globules and columns, Experiments on
liquid drops, 52, 121
Glowworms and lightning, 13
INDEX.
Glycerine in developing platinum prints,
Use of, 312
Gneiss, The Moine, 61
Goby, P., New method of radio-micro-
graphy by, 388
Gradenwitz, Dr. Alfred, 204, 209
Graft hybrid Cylisus adami, The, 145
Gravitation, The fourth dimension and its
bearing on the cause of universal, 242
Gray, John, 140
Greenwich, Meteorology and magnetism
at the Royal Observatory, 269
Grew, E. S., 1, 115
HAIG, HAROLD A., 8
Hair of Echidna, Fungus growing on,
276
Hairs of animals, 283
Hall effect, The, 224
Hardy, Major Hurlstone, 166
Harness together, A horse and cow in, 138
Harrison, B. G, 71, 91
Hartog, Marcus, 240
Harvard Observatory, The work of, 305
Harvest weather forecast, 221
Health, Climate and, 310
Heart-weight to muscular effort, Relation
of, 107
Hemisphere, Daily weather maps for the
northern, 433
Hen birds assuming the plumage of the
male bird, 189, 288
ostrich with plumage of a cock, A, 7
Henkel, F. W„ 68, 128, 156, 233, 323
Hermaphrodite bees, 392
Hill, J., Arthur, 257
Holmes, Edwin, 239
, George G, 185
Hornet as a pet, The, 166, 240
Horse and cow in harness together, A, 138
chestnuts. Utilisation of, 182
Humble-bee, The red-tailed, 161
Hume, John, 409
Hurricane, typhoon, and cyclone, 309
Hurricanes of the West Indies, 309
Hutton, E. Ardron, 65
Hybrids of Boron, 145
Hydrogen, Professor Fowler's discovery of
a new series of lines in the spectrum
of, 18
Hydroid on a parasitic copepod, A,
354
Hydrophyllaceae, The family, 345
" Hypo " in mounts, prints, and washing
water, Testing for, 466
Hypotheses, Cosmological, 369
IBERIAN PLANTS IN SOUTH-WEST
IRELAND, SUGGESTIONS TO-
WARDS A SOLUTION OF THE
PROBLEM OF THE, 212
Illumination and ultra-microscopic
methods in Botany, Dark-ground, 361
, Dark-ground, 148
Illuminator, A dark-ground, 102
India, African element in freshwater
fauna of, 393
Ink regulations. New German, 219
Innes, R. T. A., 369
Insect intelligence, 24
protected by its meals. An, 275
Insects, Death feigning in, 276
, Sleeping, 107
Ireland, Iron-ores and bauxites of North-
East, 101
, Suggestions towards a solution of
the problem of the Iberian plants in
South-West, 212
Iron bacterium, A new, 266
ores and bauxites of North-East
Ireland, 101
Isostasy, Topography, earth-movements,
and, 308
JAPAN, VEGETATION OF, 180
Jobling, E., 294
Johnston, John, 93, 155, 252
Jupiter's third satellite, Ganymede, 1911,
August 13th, The occultation of the
Star Mayer 588 by, 97
KANSAS, MARCH 23rd, ELECTRICAL
STORM IN, 349
Katscher, Leopold, 205
Keegan, P. Q., 153, 367
King-crab on the surface, A, 187
LACTOSE IN THE SOLID STATE, A
SIMPLE METHOD OF DIF-
FERENTIATION BETWEEN MAL-
TOSE AND, 322
Lake Tanganyika, Variation of the water-
level of, 347
Laking, Guy Francis, 93
Lambert, F. C, 23, 148, 350
Land classification and geology, 465
Lava, Preservation .of plant fossils in,
386
Lawson, Blackford, 167
Leaf-fall, Cause of, 219
Lead, Action of alkaline water on, 463
Leaves, Bacterial nodules on, 306
Lectures, Recent, 151
, Selborne Extension, 334
Leeches, Breeding, 275
Leitneria, The genus, 18
Lenses, " Adon " telephoto, 107
Lens shade, A simple form of, 392
Le Souef, Dudley, 189
Lettuce rubber, Wild, 346
Lichens, Antarctic, 265
Life and reproduction, Problems of, 239
Light filters, Testing dark-room, 223
-, Utility of sensitiveness to, 187
— — variation of Eros, The, 305
Lightning, Deaths by, 220
flashes, 438
, Glowworms and, 13
Lime on soil, Action of caustic, 346
Ling, Philip H., 171
Liquid columns, 121
drops, globules, and columns, Experi-
ments on, 52, 121
, Stretched films of, 115
Liquids, Density of, 25
Liverwort Thallus, Air-chambers in, 99
Liverworts, Alpine mosses and, 99
Lizard and Meneage, Geology of the, 22
Lockett, A., 327
London Wells, 183
Lowell, Percival, 252
Luminescence analysis, 100
Lungs, Effect of school work on the, 209
MACGREGOR, MALCOLM EVAN, 197,
214
Maggots in man, 152
Magnetism at the Royal Observatory,
Greenwich, Meteorology and, 269
Magnifier, An improvement in the hand,
388
Maltose and lactose in the solid state, A
simple method of differentiation be-
tween, 322
Manganese in animals, 187
Man in South America, Early, 347
, The distribution of, 429
Mann, Francis P., 391
Maoriland, The deities of ancient, 454
Maps for the Northern Hemisphere, Daily
weather, 433
Mar lev, J., 326
Marriott, William, 220, 269, 309, 348,
386, 433, 465
Mars, 288, 439
, Considerations on the physical ap-
pearance of the planet, 193, 238
, The Planet, 252
Marsden, E., 55
Martin, Geoffrey, 34. 41
, Maud S., 401
Maxwell, J. E., 239, 439
Measures nearly hydrometric, British, 373
Mediterranean, Oceanography in the, 385
Memoirs, Recent American, 146
Mendelism and pigmentation, 19
Meneage, Geology of the Lizard and, 22
Mercury vapour lamp, The, 314
Merope Nebula in the Pleiades, The, 179
Metallurgical Chemistry Notes, Engineer-
ing and, 429, 464
Metals, Institute of, 219
Metaphysics, The neglect of, 154
Meteorological Committee, International,
270
instruments, Verification of, 349
Meteorology and magnetism at the Royal
Observatory, Greenwich, 269
, Fishery research and, 433
Notes, 220, 269, 309, 348, 386,
465
Metropolitan Water Board's report,
Metz, C, 273, 311
Microscope, A new model, 221
, A portable, 222
Objective, On the relation of aper-
ture to power in the, 63, 102, 148, 189
, Taking cinematograph pictures with
the, 105
, The making of a, 244
, The mechanical construction of the,
183
Microscopic examination of coal, The, 347
Microscopical Club, Quekett, 23, 102, 147,
183, 312, 466
Society, The Royal, 23, 105
Microscopy Notes, 22, 62, 101, 147, 183,
221, 270, 310, 349, 388, 433, 466
Micro-organisms producing arsine, 463
slides, A useful pocket-case for,
147
Milk weed. Utilisation of, 182
Milky Way, Photography of the, 59
, Spiral theory of the, 217
Mimicry, A study in, 161
Mines, Prehistoric emerald, 124
Mitchell, C. Ainsworth, 21, 60, 100, 145,
182, 219, 266, 283, 307, 346, 384, 463
Moine Gneiss, The, 61
Moon, F. W., 409
, The, 260
Moon's motion, Professor Newcomb's last
researches on the, 344
origin, Problem of the, 71, 91
Mosses and liverworts, Alpine, 99
, Xerophious adaptations in, 98
Moth's love signal, A, 107
Motor fuel, Alcohol as a, 182
— — spirit. The future of, 266
433,
21
INDEX.
Mount Wilson one-lmndred-inch reflector,
The, 217
Mull, Sapphire in, 386
Muscular effort, Relation of heart-weight
to, 107
Museum, A plea for a British folk-, 299
and its guide. An " Ideal," 15, 93,
155
, The historical medical, 374
NATAL, VEGETATION OF, 265
Natural History notes from Bolivia and
Peru, 152
Nature Photographic Society, The
exhibition of the, 450
Nebula in the Pleiades, The Meropc, 179
, Parallax of the Andromeda, 264
, The Andromeda, 461
Nebulae, Distribution of clusters and, 461
Negatives, Reversed, 106
Negro man in Britain, 123
Negroes, Spotted, 224
Nelson, Edward M, 222
Neon and Xs, 435
Neptune, Belts on, 265
, Limiting distance for hypothetical
satellites of, 18
Nest made by Orang Utan, 392
Nesting-box Exhibition, 105
boxes in Russia, 25
Nests of the song thrush and blackbird
The, 343
Newcomb's last researches on the Moon's
motion, Professor, 344
New Zealand, A physiographical study in,
385
, Solar observatory in, 364
Nicholson, W. A., 173
Nitrogen by felspar, The fixation of, 463
■ , The active modification of, 346
Nodules on leaves, Bacterial, 306
Nomenclature of variable stars, The,
421
Notes, 17, 59, 97, 143, 179, 217, 264, 305,
344, 383, 425, 460
Notices, 40, 79, 120, 160, 200, 224, 240,
280, 320, 360, 400, 440, 468
Nottinghamshire, The concealed coalfield
of Yorkshire and, 268
Nova Geminorum, 59
OBITUARY, 17, 179, 218, 265
Observatory, Ben Nevis, 386
," Campbell's " Stellar Motions," and
Sir David Gill's " History of the Cape,
461
, Greenwich, Meteorology and mag-
netism at the Royal, 269
in New Zealand, A Solar, 364
, Stony hurst College, 196
, The work of Harvard, 305
Oceanography of the Mediterranean,
385
O'Halloran, Sylvester N. E., 114
Orang Utan, Nest made by, 392
Orchids, Germination of, 98
Origin of Life," " The, 373
Ornithology Notes, 24, 105, 149, 274
Orthoptera, Gizzard in beetles and, 276
Oscillations, Undamped, 187
Ostrich with plumage of a cock, A hen, 7
Oxygen starvation, 152
Ozone on fibres, Action of, 346
PALAEOLITHIC MAN, RAISED
BEACHES AND, 220
Panama Canal, Probable effects of the,
347
Parallax determinations, Yerkes', 425
of the Andromeda Nebula, 264
, Stellar, 143
Paramoecium , Five-year pedegreed race of,
27
Parents' National Educational Union,
The annual conference, 174
Parr, W. Alfred, 4
Pathogenic organisms in river water, 428
Pearls from gelatin, Imitation, 267
Pennatulids, Phosphorescence of, 468
Periwinkles and the tide, 393
Peru, Natural History notes from Bolivia
and, 152
Pethen, Robert W., 13
Petroleum products, Formation of, 100
Petrology of sandstones, 22
Phasmidae, Catalepsy in, 333
Phenological observations, 221
Phenomenon, A physical, 114
Phosphorescence of pennatulids, 468
Photoelectric effect, The, 26
Photographic effect of chemical reactions,
326
Society, The exhibition of the
Nature, 450
Photographing rock sections, 25
Photographs at high pressure, Spark, 467
, Faulty perspective seen in many,
391
Photography, Astronomical, 252
for amateurs, Stellar, 449
Notes, 25, 65, 106, 150, 185, 222, 274,
312, 350, 391, 434, 446
with a pin-hole, 65
small telescope, Simple
directions for, 252
Photometer, The Selenium, 265
Photo-micrographic apparatus, A new,
349
Photo-micrography. — Backgrounds, Low-
power, 22
Phyllotaxis and the discal florets of com-
posite flowers, 188
Society, Meeting of the, 243
Physics Notes, 25, 151, 186, 224, 275, 313,
435, 467
Physiographical study in New Zealand,
A, 385
Pianoforte touch," " The dynamics of, 186
Pigmentation, Mendelism and, 19
Pisidium, The British species of, 273
Pitcher plant Dischidia, Biology of the,
307
Planet Albert, The, 306
Mars, Considerations on the physical
appearance of the, 193, 238
, The, 252
, The existence of an Ultra-Nep-
tunian, 171
Planetary distances, The, 426
Planets, Measures of the, 144
, The Albedoes and brightness of the,
17
, Trojan group of, 306
, Ultra-Neptunian, 218
Plant fossils in Lava, Preservation of, 386
life, Problems of, 201
protection, 317
Plants, Biology of desert, 59
, Cushion, 346
in South- West Ireland, Suggestions
towards a solution of the problem of
the Iberian, 212
in South Germany in 1911 and 1913,
The flowering of, 458
, Occurrence of formaldehyde in, 267
, The formation of alkaloids in, 463
to freezing, Resistance of, 60
Platinum printing, 274
— ■ — toning, 350
Platinum prints. Use of glycerine in
developing, 312
, Warm tones in, 312
Pleiades, The merope nebula in the, 179
Plumage of a cock, A hen ostrich with, 7
question, The, 357
the male bird, Hen birds assum-
ing the, 189, 288
Pocket-case for micro-slides, A useful, 147
Pocock, R. J., 67
Poison of amphibian skin, 435
Polarissima, The star, 264
Polygons, On the construction of regular,
337
Polytoma, Auxetic action on spores of a
new species of, 109
Pomace-fly, Fecundity of the, 276
Powell, T. H., 210
Preservation of Birds, The Committee for
the Economic, 274
Pressure gauge, 435
Price, S. Reginald, 201, 361
Prideaux, R. Morris, 283
Printing, Platinum, 274
Prints, and washing water. Testing for
" Hypo " in mounts, 466
, Fading of silver, 150
, Glazing silver, 434
Proctor, Mary, 364
Psychidae, 62
Psychology of telescopic vision, The, 4
yUARTZ, IGNEOUS, 183
Queketter, 148
Quekett Microscopical Club, 23, 102, 147,
183, 312, 466
RACE ? HOW DOES EXPERIENCE
COUNT FOR THE, 26
Radiation, Rontgen, 186
Radio-active substances. Nomenclature of,
313
Radio-micrography by P. Goby, New
method of, 388
Rain gauge, The " Fernley " self-recording,
348
Rainbow cup, Professor Boys', 115
Rainfall, 1912, British, 387
, Duration of, 465
Rainwater, Hardness of, 219
Reaction, Photographic effect of chemical,
326
Redgrove, H. Stanley, 68, 108, 239, 289,
337
Reflector, The Mount Wilson one-hundred-
inch, 217
Regenerative capacity, Extraordinary, 187
Keid, R. W., 454
Reports, 420
Research Defence Society, 84
Respiration in the water boatman, 314
Reviews, 29, 74, 116, 157, 190, 227, 277,
318, 358, 397, 440, 447
Aeronautics, 157
Anthropology, 74
Archaeology, 318
Astronomy, 29, 74, 157, 227, 277
Aviation, 447
Biology, 397
Botany, 158, 228, 397
Chemistry, 31, 75, 116, 158, 190, 277,
319, 358, 397, 440, 447
Economics, 278
INDEX.
Reviews (cont.) —
Engineering, 440
Ethics, 278
Geography, 117, 158, 191, 358, 448
Geology, 32, 75, 191, 230, 319, 398
History, 398
Horticulture, 359
Mathematics, 278
Medicine, 75
Meteorology, 33
Microscopy, 231, 440
Mining, 117
Natural History, 359
Oceanography, 448
Ornithology, '117, 279, 359, 448
Painting in North Italy, 76
Philosophy, 76, 231
Photography, 33
Physics, 33, 77, 118, 232, 319, 448
Physiology, 360, 398
Political Economy, 398
Psychology, 279
Radio-activitv, 77, 118, 360
Sport, 399
Year Books, 78, 120, 232
Zoology, 33, 78, 119, 159, 192, 232, 280,
320, 360, 399, 440
Rhizocephalan, New, 107
Riebeckite rock from Arran, A, 146
Right-handed ? Why are we, 205
Ripening of fruits, The artificial, 300
River water, Pathogenic organisms in,
428
Robinson, Louis, 410
Rock-formers, Calcareous algae as, 430
Rock from Arran, A Riebeckite, 146
sections, Photographing, 25
Rbntgen radiation, 186
Rowan, William, 132
Royal Institution, The, 134
Microscopical Society, The, 23, 105
— — Observatory, Greenwich, Meteoro-
logy and magnetism at the, 269
Society's Conversazione, The, 224
Rubber, Synthetic, 34, 41
, Wild lettuce, 346
SALVINIA, DEVELOPMENT OF, 18
Sandeman, John Glas., 68
Sandstone at Southall, Old Red, 219
Sandstones, Petrology of, 22
Sapphire in Mull, 386
Sardine, Races of, 435
Satellite, Saturn's ninth, 264
, Ganymede, 1911, August 13th, The
occultation of the Star Mayer 588 by
Jupiter's third, 97
Satellites of Neptune, Limiting distance
for hypothetical, 18
Saturn, 18
Saturn's ninth satellite, 264
Scales in Siren, Vestiges of, 152
Scallop's eyes, The, 152
Schaumasse's Comet, 265
new comet, The orbit of, 218
Schmidt, Peter, 333
Scholes, J. W., 334
School Science Societies, 68
work on the lungs, Effect of, 209
Scintillations, 55
Sea-horse, Movements of the, 152
Sea-sickness, The true cause of, 253
Sector shutters, 313
Seeds, Biological method of identifying,
307
, Testing the vitality of, 384
, The " After-ripening " of, 306
Selaginella, A British fossil, 218
Selborne Extension Lectures, 334
Selenium photometer, The, 265
Senior, Edgar, 25, 65, 106, 150, 185, 222,
274, 312, 350, 391, 434, 466
Sense of direction, 152
Sensitiveness to light, Utility of, 187
Serpents, Feeding habits of, 107
Shingle beach, The, 1
Shrimps, Behaviour of fairy, 435
Shutter, Sector, 313
Signalling among Termites, 435
Signals, Effect of atmospheric conditions
on wireless, 466
Silkworm, Chemistry of the, 353
Silver prints. Fading of, 150
— — , Glazing, 434
Siren, Vestiges of scales in, 152
Skin, Poison of amphibian, 435
Skull, The Sussex, 61
Sky, The face of the, 28, 57, 112, 139, 177,
225, 250, 303, 355, 381, 436, 457
Smith. T. F., 105
Soar, Charles D., 127, 312
Sodium radio-active ? Is, 275
, Reduction of metallic chlorides by,
100
Soil, Action of caustic lime on, 346
Solar activity, Signs of reviving, 59
eclipses, 59
disturbances, 27, 69, 108, 143, 188,
227, 260, 314, 340, 394, 438, 460
observatory in New Zealand, A,
364
radiation from free balloons, A
measure of, 97
, Possible short-period variations
in the, 144
Southall, Old Red Sandstone at, 219
Specificity, 393
Spectrograph, A new grating, 142
Spectro-heliograph, The, 217
Spectroscopic determination of the Sun's
rotation, 217
Spectroscopy for beginners, Stellar, 407,
441
Spiders, Cave, 276
Spiral theory of the Milky Way, 217
Spirit, The future of motor, 266
Spontaneous generation, Some notes on
the history and significance of the
theory of, 289
Spores of a new species of Polytoma,
Auxetic action of, 109
Star Mayer 588 by Jupiter's third satellite,
Ganymede, 1911, August, 13th, The
occultation of the, 97
Polarissima, The, 264
Starfish see ? How much does a, 276
Stars, Appeal for more volunteers for
observation of variable, 306
, Determination of radial velocities
of fainter, 460
■ , Giant and dwarf, 383
, Prolonged observations of tem-
porary, 264
, The Double (and Binary), 128, 239
, nomenclature of variable, 421
, number of " Double," 293, 334
, visible, 383
, sizes and distances of the, 179
, Spurious diameters of, 298
Steavenson, W. H., 449
Steel, The critical points of, 429
Stellar distance units, 298, 334
" Motions," and Sir David Gill's
" History of the Cape Observatory,"
Campbell's, 461
parallax, 143
photography for amateurs, 449
spectroscopy for beginners, 407,
441
Stenhouse, T., 429, 464
Stereoscope, The modern evolution of the,
327
Stevens, A., 267, 308, 347, 385, 429,
464
Stonyhurst College Observatory, 196
Storm in Kansas, March 23rd, Electrical,
349
Stormer, Professor Carl, 263
Storms on the Atlantic, January, 1913,
220
Strickland, W. W., 189
Stuart, A. H., 142
Subliminal Self, The, 257
Sugar from saw-dust, The manufacture of,
60
Sulfinol developer, 353
Sulphide Ores, The enrichment of, 430
Summer of 1911, Some effects of the hot,
dry, 70
Sun, 1913, September 29th, The partial
eclipse of the, 459
, The magnetic field of the, 345
Sun's radiation, Variation in the, 264
rotation, Spectroscopic determination
of the, 217
Sunspots, 143
— — for prominences, Attraction of, 59
Sussex skull, The, 61
Swallow ringed in Staffordshire and re-
covered in Natal, 105
Swifts, The late stay of, 105
Synthetic rubber, 34, 41
TANK, CALCITE CRYSTALS FROM
A WATER, 464
Tarred roads upon vegetation, Effect of,
267
Teeth in upper jaw of sperm whale,
Functional, 314
Tektites, Origin of, 465
Telephoto lenses, "Adon," 107
Telescope, Simple directions for photo-
graphy with a small, 252
Telescopic vision, The psychology of, 4
Tendrils, Strength of, 98
Termites, 388
, More about black, 393
, Signalling among, 435
Tetra-iodide, Carbon, 307
Thomson, Professor J. Arthur, 26, 67,
107, 152, 187, 224, 275, 314, 353,
392, 435, 468
Thorianite, Composition of, 61
Thrush and blackbird, The nests of the
song, 343
Thunderstorms in Egypt, 433
Tick, An Australian, 221
Tide, Periwinkles and the, 393
Timber trees, Indian, 345
Toning, Platinum, 350
Topography, Earth-movements and Iso-
stasy, 308
Tornado in Wales, 465
Tornadoes of March 23rd, 1913, The U.S.,
349
Tree growth, Wind and, 144
Trees, Indian timber, 345
Trilobites, Habits of, 187
Trojan group of planets, The, 306
Trombidoidea, 127
Trypanosomes, 197, 214
Tubes, Commensal crustaceans in Chaeto-
pterus, 468
, Corrosion of condenser, 429, 464
Turquoise, Origin of, 268
Typhoon, and cyclone, Hurricane, 309
Tyrrell, G. W., 22, 61, 101, 146, 183, 219,
268, 308, 347, 386, 430, 464
INDEX.
ULTRA-MICROSCOPIC METHODS IN
BOTANY, DARK-GROUND ILLU-
MINATION AND, 361
Ultra-Neptunian planet, The existence of
an, 171
planets, 218
Units, Names for the, 265
, Stellar distance, 298, 334
VALLEYS, THE STREAMLESS DOWNS
AND THEIR DRY, 281
Vapour lamp, The mercury, 314
Variable stars, The nomenclature of, 421
Vegetation, Effect of tarred roads upon,
267
of Japan, 180
Natal, 265
Velocities of fainter stars, Determination
of radial, 460
Vesta, The Path of, 317
Vincent, J. H.F 326
Volcanic dust and climatic changes, 433
Volcanoes, Quantitative study in active,
220
Volunteers for observation of variable
stars. Appeal for more, 306
WALES, TORNADO IN, 465
Wallace, The late Alfred Russel, 456
Warbler in Ireland, The Dartford, 24
Water on lead, Action of alkaline. 4(13
, plants, Biology of submerged, 345
tank, Calcite crystals from a, 464
, Testing for " Hypo " in mounts,
prints, and washing, 466
, Use of copper sulphate for purifying,
101
Waters, In very deep, 394
Waves, Electric, 81
Weather, Aeroplanes and, 387
forecast, Harvest, 221
maps for the Northern Hemisphere,
Daily, 433
Webb, Wilfred Mark, 24, 105, 149, 244,
274, 343
Weeds of arable land, 144
Wells, London, 183
West Indies, Hurricanes of the, 309
Westphal's Comet, 425
Whale, Functional teeth in upper jaw of
sperm, 314
Wheat berry. The influence of age on the
vitality and chemical composition of
the, 85, 135
Whymper, R., 85, 135
Wiggins, Tressillian, P., 114
Wild duck, Reproductive disharmony in,
187
Williams, W. P., 252
Wilson, S. A., 318
Fiammetta, 318
Wind and tree growth, 144
Winds in the free air, 269
Wireless signals, Effect of atmospheric
conditions on, 466
Withershins, Withy winds and, 175
Withy winds and withershins, 175
Wood, H. E., 439
•— , Mrs., 459
Woodland succession, Climate change and,
218
Worlds to conquer, Fresh, 459
X3 ?, 313
, Neon and, 435
X-radiation, The nature of, 378
X-rays, Crystals and, 185
, Fabrics opaque to, 61
YERKES' PARALLAX DETERMINA-
TIONS, 425
Yorkshire and Nottinghamshire, The con-
cealed coalfield of, 268
Yule, G. Udny, 141
ZIRCONIUM, STUDIES OF THE
ELEMENT, 267
Zodiacal light, The, 323
Zoological Society's menagerie, Additions
to the, 282
Zoology Notes, 26, 67, 107, 152, 187, 224,
275 314. 353, 392, 435, 468
Printed for the Proprietors (Knowledge Publishing Company, Limited), by John King, Ealing and Uxbridge.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted bv Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
JANUARY, 1913.
THE SHINGLE BEACH.
By E. S. GREW, M.A.
Alike in Europe on its north-western and western
shores, and in the United States along the eastern
coast of North America, as well as along the
coast of Peru, the wandering sand-dune has been an
object of systematic and continuous study. The
shingle beach, as Professor F. W. Oliver, F.R.S.
has recently pointed
out in The New
Phytologist, has re-
ceived, on the other
hand, comparatively
little attention, pro-
bably because in the
countries where atten-
tion to the sand-dune
has been an economic
necessity, the shingle
beach is of compara-
tively small import-
ance. But in Great
Britain the shingle
beach is not unimportant. It is part of the drift of
our coasts, and as such plays a very important role as
a defence against the wastage of the shore-line — a
point which has been emphasised in the recent
Report on Coast Erosion. The extent of the
British shingle beaches is hardly realised, though
few holiday-makers at the seaside will have found
themselves at any distancefrom some shingledrift,and
there are actually some three hundred miles of the
coast of England and Wales lined by shingle. Even
the most casual observation of these deposits reveals
that they are not entirely stationary, and that their
FIGURE 1. Sketch Map of the Blakeney Bank, showing systems of
hooks at A, B and C. 1, 2 and 3 denote areas of marshes in the
order in which they were reclaimed. The arrow above the letter S
in " salt," indicates the position of the bank whose tip was turned
at a right angle in 1911.
presence must influence the hinterland where they
occur, if only to the extent of protecting golf links
from the surrounding sea, as at Felixstowe, or of
threatening them with curtailment as at Westward
Ho ! To the geologist and botanist they offer many
interesting problems, both in respect of their own
increase of material,
and in the vegetation
for which they afford
either protection or a
difficult foothold.
Professor Oliver's
interest in shingle
beaches is chiefly
botanical, and in its
direction is analogous
to the inquiries which
have been pursued by
him and by the stu-
dents of University
College, for a number
of years past in Western France. At Erquy, in
Brittany, an area of salt-marsh was selected some
seven years ago, and on this area has been noted the
distribution of zones of vegetation ; the physical
characters of the soil, its salinity, and the plants
appropriate to such conditions ; the migration of
the plants, and so on. A large number of problems
have arisen out of this field of study : and some
of them are repeated in different aspects in the
neighbourhood of the shingle beach. But in order
to define them, it is necessary to comprehend first
the methods of formation of the beach ; and to this
KNOWLEDGE.
January, 1913.
question Professor Oliver, to whose article we are
indebted for the information which is to follow, gives
preliminary attention.
Shingle banks arise when suitable materials from
the waste of the shore find their way into the
currents which run along the coast. In these shallow
waters the shingle is always on the move owing
to the action of the waves,
and is kept steadily moving
in the direction of the current.
Heavy seas, and on-shore
gales pile the shingle up above
high-water mark and thus
form the banks or beaches.
These are of three types : —
(1) The Fringing Type.
— This is the simplest case,
the shingle being directed by
the shore current and forming
a strip in contact with the
land on top of the sand beach.
There are many examples of
this kind of shingle beach in
Sussex.
(2) The Shingle Spit. — Suppose now that the
coast line suddenly changes its direction, and turns
inwards, while the current running along it still goes
shooting past the point of deflection. The drifted
shingle accumulates along the line of the current
to form a bank or causeway, often reaching a
length of several miles. This type is attached to
the shore at the point where the current leaves
it, and then runs straight on or with a gentle
curvature towards its
growing distant end.
It generally turns
inward. Examples are
Hurst Castle Bank
and Blakeney Bank.
(3) The Bar —
When a shingle spit of
this kind continually
stretching and grow-
ing touches land again
it forms a bar. Por-
fessor Oliver notes
that the Chesil Beach
which is so conspic-
uous a feature at the
Isle of Portland (its
eastern extremity)
seems at first sight to
belong to this
category; but its
exact status is still a matter of discussion.
(4) The Apposition Type. — Sometimes the
pushing current by changing its direction or force has
not enough strength to carry the shingle to the end
of the bank ; or else the end of the bank has been
hooked inwards so far that the current cannot reach
it. In these cases the spit cannot lengthen and the
additions of shingle are merely dropped by the
Figure 2. Apposition type of Shingle Bank.
A, B, C, indicate a point of land; the arrow
marks the direction of coastal drift ; the suc-
cessive shingle banks lie to the right of the
figure ; modified from F. Drew.
Scale ofhtxlzs
Figure 3. Sketch Map of the Chesil Bank (after Bristow and
Whitaker) to show the relations of Bank, Mainland and Fleet.
Shingle is drawn thick black.
current on the flank of the forming bank. These
additions may be lifted above the top of the bank by
a high tide or gale. In this way a succession of
more or less parallel banks may be thrown up one
behind another, with the result that very extensive
areas of shingle are produced.
The outstanding example of this type is
Uungeness (see Figure 2).
To return to the Shingle
Spit. As already explained,
the point at which the
spit leaves the shore is a
salient angle of the main-
land. The axis of the bank
runs along the line of the
current and generally presents
a gentle convex curve to
the sea. As a rule this
type runs at some distance
from the shore line, the
protected area between bank
and shore being occupied
by salt marshes subject to
the tides. These salt marshes
are practically a kind of littoral shelf on the edge
of which the shingle rests : and they often offer
facilities for reclamation. The spits which protect
them most often pursue their course from the point
where they are attracted to the mainland, without
any alteration in character beyond an occasional
narrowing or widening. The Aldeburgh bank in
Suffolk goes right on to its apex without alteration.
But usually, towards the apex, there
appears a marked
landward deflection
in the form of a
hook : and frequently
several hooks are
present in close prox-
imity (Hurst Castle,
Hamstead, Dover) :
while, as at Blakeney,
there are occasionally
extremely complex
systems of hooks (see
Figure 1). "One of the
hooks at Blakeney
has in recent years
become exposed to
gales from the north-
west in consequence
of the wasting of
the top of the main
bank which formerly
masked it. At Easter, 1911, a succession of heavy
gales from this quarter removed the terminal portion
of this hook and deposited the eroded material as a
new bank one hundred and forty feet long, fifty feet
wide, and over six feet high, at right angles to the old
hook, on its lee side" (see Figure 5). Professor
Oliver concludes that a shingle spit has quite definite,
successive phases. There is the phase of youth in
January, 1913.
KNOWLEDGE.
Figure 4.
which growth is mainly in length ;
and this is followed by a more
or less prolonged phase of hook
formation, when the action of the
current begins to yield its domin-
ation to the activity of the gale.
Blakeney Bank illustrates in its
finger-like stretch of two miles the
formation of multiple hooks on the
grand scale (see Figure 6) ; and
here there seems to be evidence
of the oscillation of conditions
in which the current and the
wave have alternately triumphed.
The Chesil Bank, which furnishes
the most considerable and impos-
ing accumulation of shingle in the
British Isles, forms a problem by itself. It stretches
fifteen miles as a continuous strip from Burton
Bradstock to Portland (see Figure 3). The height of
its crest above high water mark ranges from twenty
to thirty feet, while its width averages five hundred
feet. The roar of a south-western gale on its pebbles
at the Isle
of Portland is
a sound which
lingers in the
ears of anyone
who has ever
slept, or lain
awake, during
a night there.
From Burton
Bradstock to
Abbotsbury (six
miles) the Chesil
Bank fringes the
From a Photograph ly
Figure 5
mainland (see
Figure 4) ; from
this point to
Portland the bank is separated from the land by a
shallow estuary, the Fleet, or Backwater, about
eight miles long, and sometimes half a mile in width.
As already observed the Chesil Beach might be
regarded possibly as a Spit or a Bar. Quite recently
**2 ^mT-
-**■
* •-^■^^fc .
- -^^^^^i
^^^^^
*jjfi&^
**-''&m
^^^^^
1M£
m ■
Figure 6. Inner edge of Blakeney Main Shingle Bank encroaching on the
" Marains," looking west. The bushes are Suacila fruticosa.
Chesil Bank looking S.E. from a point opposite Burton Mere,
near Burton Bradstock.
it has been thought to have developed not as a spit
but as a fringing beach behind which the land has
retreated in consequence of sub-aerial denudation.
The Fleet or Backwater would thus have been
excavated behind the bank. Professor Oliver
remarks on a peculiarity of the Chesil Bank,
confirmatory
of this theory,
which is that the
bank presents
not a convex
but a concave
front to the sea.
There are many
other problems
of the shingle
bank, especi-
ally the move-
ments of its
hooks, and the
percolation of
water through
it — for which
further reference may be sought in Professor
Oliver's original work ; and there, too, will be
found an outline of the development of the
flora of the beach. One of the outstanding
mysteries of the shingle spit is its water supply and
the plants which are nourished
by it. The lower parts of
the spit are tenanted by plants
which do not need salt. Above
them there is a residuum of plants
intolerant of salt. Where do they
obtain the water to nourish them ?
Such water exists, and is indeed
astonishingly copious, in the
interstices of the shingle. In last
year's burning summer the upper
vegetation of shingle spits pros-
pered, and the sheep fed on it —
especially on the Chesil Bank. The
source of this water is possibly
to be attributed to the formation
of internal dew in the shingle.
E. J. Salisbury, July, ic,
A new hook at Blakeney Point, formed in March-April, 1911, on
the bank marked with an arrow in Figure 1.
THE PSYCHOLOGY OF TELESCOPIC VISION
By W. ALFRED PARR.
Little Buttercup, of "H.M.S. 'Pinafore' " fame,
gave vent to a profound piece of general philosophy
when she assured Captain Corcoran, of that vessel,
that " Things are seldom what they seem." Now,
although this is a fundamental verity familiar enough
to us all, we are occasionally reminded of the
peculiar virtue underlying this Gil-
bertian dictum in quite an unexpected
manner when looking through a tele-
scope. If we regard a far-off land-
scape through a powerful telescope,
fitted with an erecting day eyepiece,
we soon become aware of the fact
that any distant cottages or houses
which our landscape may contain
appear to us strangely out of drawing.
More especially is this the case with
such houses as happen to have their
longest sides parallel to our line of
sight, so that we look along them, as
it were, instead of squarely at them.
We shall find, on examining these
closely, that, instead of presenting
the ordinary aspect we are accustomed
to associate with the rules of fore-
shortening, they boldly bid defiance
to all our ideas of perspective and
stand out at us in a manner which is
truly astonishing. And, if we recall
the statement we so often hear, that
the function of a telescope is to make
a far-off object appear as if it were
only at a short distance from us, our
astonishment will be the greater, since
no houses within our previous
experience wear such a curiously
distorted guise as these.
It was claimed by the pro-
moters of the giant telescope,
which was intended to form the clou of the
Paris Exhibition in 1900, that the moon was to
be brought by this instrument literally within our
grasp ! — if we could reach a metre — and popular
accounts of the great Yerkes telescope affirmed that
it would make our satellite appear just as it would
be seen with the naked eye if it were suspended but
sixty miles over our heads. Such irresponsible
statements as these are not only in the highest
degree misleading in themselves, as I ventured to
point out some years ago in a letter to the British
Astronomical Association,* but, even supposing the
exaggerated claims, just quoted, as to the " approxi-
mating " power of a great telescope to be possible of
realization, it can still be shown that the telescopic
image of an object is vastly different from the actual
aspect that object would present if viewed by the
naked eye at the same apparent distance. This
somewhat ignored fact is a distinct and important
feature of telescopic vision ; for it has an interesting
bearing on our interpretation of tele-
scopic pictures in general, be they
astronomical or terrestrial.
Now, our surest way of keeping
this peculiar action of the telescope in
mind is to remember that, far from
even apparently bringing distant
objects nearer, as the popular claim
has it, the telescope in reality merely
enlarges the naked-eye view. It
brings to our notice objects which, by
reason of their great distance from us,
would otherwise remain beyond the
limits of critical vision, and thus
enables us to see them under conditions
different from those under which our
experience is usually gained. In other
words, the telescopic image and the
naked-eye image are essentially copies
of one another on varying scales, and
it is only in our different interpretation
of these scales that the peculiarity
of telescopic vision resides. Distant
objects are habitually seen under a
small visual angle, and they conse-
quently fail to excite our critical
notice in the same degree as do
near objects which are seen under a
larger visual angle. But when
the telescope comes to our aid
and enlarges our naked-eye view
for us, we are apt to fall into
error, and, if we do not in reality
consider ourselves suddenly confronted with an
actually nearer object, we, at any rate, regard that
object with all the inferences which the enlarged
image conjures up in our minds. We mentally
endow the magnified retinal image with all the
attributes which an object of its apparent size would
possess, and fancy our larger picture also nearer, in
conformity with our past association of largeness and
nearness. We must remember, however, that in
looking through a telescope we become aware of
conditions which are foreign to our usual experience,
and of which, but for the instrument's power, we
should have remained in ignorance.
Thus, to consider for a moment the simple
See Journal Brit. Astro. Assoc, Vol. IX, p. 271.
January, 1913.
KNOWLEDGE.
geometrical aspect of the question in its relation to
astronomy, as illustrated in Figure 7, where the
circle M may be allowed to
represent the moon, it is
clear that the portions of the
lunar surface at A and B are
seen under what we can
only describe as unnatural
conditions when viewed tele-
scopically from E, since they
would remain wholly invisible
to an observer capable of
inspecting the moon at close
quarters. Now, when we
apply a powerful telescope
and bring the moon appar-
ently nearer, as at m, the
portions of the lunar limb
at A and B remain visible,
instead of lying beyond our
sight at a and b, as the
figure shows the}- would do,
if we were in reality as near
the moon as the telescope
apparently brings us. It
follows that the lunar features
near the limb are always seen
under a certain amount of
distortion, which decreases
as we approach the centre
of the disc; but so familiar
has this telescopic deforma-
tion become, that the eve
practically ignores it, and accepts the illusion of an
actually approxi-
mated moon. ^^^
Though a tele-
scope magnifying
onethousand times
is said to theoreti-
cally bring the
moon within a
distance of only
two hundred and
fort\- miles, we
must bear in mind
that an observer,
who might be
supposed to regard
our satellite at this
distance with the
naked eye, would
have a very differ-
ent scene present-
ed to his view from
that with which
telescopic astro-
nomy has made
him familiar. Not
Figure 8.
The Villa Fabbricotti, Florence, taken with a
telephoto lens, magnifying 15 diameters, at a
distance of .} mile.
pur view.
Figure
View of F'o-nce taken from the Palazzo Vecchio, and showing the
hills of Fiesole in the background.
only would there
be the geometrical reduction of the visible area
under altered visual conditions, would wear a different
aspect. The astronomer's eyes, in fact, have become
vitiated, so to speak, by this
peculiar action of the tele-
scope ; much as the musician
Complains that his ears have
become corrupted by accept-
ing the artificial intervals
brought intouniversal musical
practice by the adoption of
the system of tuning by equal
temperament.
But if the eye, in accepting
the illusion of an approxi-
mated moon, has learned to
tolerate selenographical dis-
tortion, since it is solely under
telescopic conditions that
lunar detail has been brought
to our notice, the case is
quite another one when we
contemplate distant terres-
trial scenery through the
telescope. Here all is fam-
iliar, and the same, or at
least similar, objects have
been originally studied by
us at close quarters, so that
when we expect to witness
the anticipated approximat-
ing effect of our telescope
we stand amazed at the
curious spectacle offered to
In Figure 8, for instance, we notice to
some extent the
singular out -of -
drawing effect of
the ordinary tele-
photograph.' The
building illustrated
has an interest of
its own, being the
Villa Fabbricotti,
just outside the
gates of Florence,
where Queen
Victoria resided in
the spring of 1894;
while the photo-
graph, which was
taken with a tele-
photo lens magni-
fying fifteen dia-
meters atadistance
of a little over a
quarter of a mile,
shows, especially
on the right hand
side, in the seeming
divergence of the
KNOWLEDGE.
January, 1913.
Figure 10. The Villa degli Angeli at Fiesole, as
photographed from Florence through a telescope
magnifying 40 diameters.
■■■■■■I
Figure 11. The Villa Torrosa, Fiesole, as photographed
from Florence through a telescope.
vision which is brought
out more vividly in a
powerful instrument.
In order to exhibit
this peculiarity to its
fullest extent, I insti-
tuted some experiments
in the photography of
distant buildings by
means of an ordinary
Kodak camera, from
which the lens had
been previously remov-
ed, attached to a three-
inch refracting tele-
scope, fitted with an
eyepiece magnifying
some forty diameters ;
and although, as might
be expected from the non-photographic character of the usual
telescopic objective, the resulting pictures leave a good deal
to be desired as regards strength and clearness, they are
sufficiently distinct to show the characteristic feature of
telescopic vision in a very striking manner. Taking advan-
tage, therefore, of the extensive view commanded from the
terrace of the Palazzo Vecchio near the centre of Florence,
I first took an ordinary photograph of the group of hills,
some three miles distant, upon which is situated the ancient
town of Fiesole, and then, combining camera and telescope
in the manner described, photographed separately some of
the more conspicuous villas embraced in the general view.
Thus Figure 9 may be regarded as representing the naked-
eye view of Fiesole as seen from Florence*, while Figures 10,
II and 12 represent the telescopic images of the villas
* The two towers in the picture, which, as here reproduced, is
necessarily seen on a reduced scale, are (from left to right) those
of the Badia and the Bargello.
■f Illusions, A Psychological Study, by James Sully, 1895 (Vol.
XXXIV of the International Scientific Series).
just discernible, and marked respectively with one, two, and
three dots, in Figure 9. Of these, Figure 12, which shows
the corner and foreshortened side of the villa marked with
three dots in the middle-distance of Figure 9, offers
undoubtedly the most violent shock to our ideas of rational
perspective, and' may for this reason be taken as a fitting
object lesson in connection with our present topic. The
distance from the observer — about one and a half miles —
and the position of the house with regard to his line of
sight, as well as the magnification employed, all conspire in
this case to produce a most interesting result ; and so odd,
in fact, was the aspect which this particular building
presented in the telescope that it was known as the Villa
Storta, or crooked villa, by those who thus beheld it for
the first time. But the crookedness is, after all, merely
psychological, for the photograph serves as a singularly
apposite illustration of what Professor James Sully calls
interpretative illusion. +
Now, as the perception of magnitude is closely connected
with that of distance, and the building depicted is sufficiently
removed from the observer for its near and far ends to be
seen under practically the same visual angle, our ordinary
ideas of perspective
are disturbed. We
are, in fact, by virtue
of the magnifying
power of the telescope,
able to contemplate
this building under
conditions foreign to
those under which our
experience has been
hitherto gained, so that
the lines of roof and
first story, instead of
converging as they
recede from us, as
would certainly be the
case if the building
were actually as near
Figure 12. The Villa Ventaglio, as photographed
through a telescope. . ..
January, 1913.
KNOWLEDGE.
the spectator as the telescope apparently brings
it, are here found to be practically parallel, since
their vanishing point, as the draughtsman expresses
it, is in this case extremely remote. We are thus
confronted with a condition of things which in the
ordinary way of life would be beyond the critical
limit of vision. But now comes an interesting
psychological moment ; for the mind insists upon
continuing its usual operation even under the
present unusual circumstances. Knowing the two
ends of a house to be of equal size, we make a habit
of mentally enlarging the reduced image of the
distant end to fit the near end ; and here, where
there is practically no dissimilarity between the
retinal pictures of the two ends, we persist in
mentally enlarging the distant end, with the curious
result that the lines of the house appear actually to
diverge as they recede from us. But that this
astonishing effect is nothing but a psychological
illusion, anyone can easily prove for himself by
simply holding the picture in such a position that
the eye can glance obliquely down the seemingly
divergent lines, when he will at once become
aware that they are practically parallel ; the
actually existing, but extremely slight, convergence
towards the distant end being quite inappreciable.
To a lesser degree the same effect may be traced
in the appropriate portions of the other telescopic
pictures, notably in the right sides of the Villa degli
Angeli (see Figure 10) and the Villa Torrosa (see
Figure 11), while it is instructive to note how per-
sistently the illusion of divergent receding lines re-
asserts itself in each of the photographs, although
we may convince ourselves with compasses and
ruler that geometrical orthodoxy in reality reigns
supreme.
This is a striking confirmation of the truth that
the same personality enters into the examination of
a photograph which is known to exist in the actual
observation of nature, and the interesting fact is once
more brought home to us in the study of such
unusual phenomena as the present, that things are
apt to change their seemings to suit our preconceived
opinions concerning them ; for our judgment is to a
great extent a process of semi-conscious inference
based upon a variety of circumstances drawn from
our past experience and sense of association. We
may, indeed, reverse the old saying in such a
case as this and claim that, here at least, Believing
is Seeing.
A- HEN OSTRICH WITH PLUMAGE OF A COCK.
By F. W. FITZSIMONS, F.Z.S., F.R.M.S.
(Director of the Port Elizabeth Museum.)
In April, three years ago, at a caponizing demonstra-
tion at Graaff Reinet, Cape Province, at which there
were over forty farmers and townsmen present,
Veterinary Surgeon Elley removed the ovaries from
three hen ostriches.
The hens were each
four years of age at
the time. Shortly
after the operation
the three hens began
to assume the black
hod}- plumage of the
adult cock bird, and
from the character-
istic drab colour of
the feathers of a
female, these feath-
ers turned jet black
and became glossy
as in the male.
Another remarkable
thing happened.
The wing and tail
feathers also
changed, and be-
came so like those
of the cock bird that
feather experts, to whom they were shewn, declared
them to be the typical feathers of a cock ostrich.
These hen ostriches belong to Mr. W. Rubige, a
Figure 13. A Hen Ostrich with the plumage of a Cock
well-known Graaff Reinet farmer, and he kindly
consented to have one of them chloroformed and
presented tothe Port Elizabeth museum for exhibition.
The bird was sent to us in the flesh, and I had the satis-
faction of making a
personal examina-
tion to make quite
sure it was a female.
There are many,
no doubt, who
will be sceptical,
but I can assure
them there is abso-
lutely no doubt
about the bird being
a female. In the
accompanying pho-
tograph, the hen
bird is shewn after
it was mounted by
my taxidermist.
It will thus be
seen that the re-
moval of the ovaries
in these three in-
stances caused re-
markable constitu-
tional changes. Hitherto we have supposed that
the ovaries, as their name implies, were concerned
only in the production of ova or eggs.
MODERN CONCEPTIONS OF CELL-STRUCTURE
AND FUNCTION.
By HAROLD A. HAIG, M.B., Lond. ; M.R.C.S., Eng.
(Lecturer in Histology and Embryology, University College, Cardiff.)
Nowadays, the study of the complex problems
dealing with cell-organisation and function is be-
coming more and more important and in certain
branches of biology, notably pathology and bacterio-
logy, is one which becomes intimately connected
with abnormal processes in the cell ; these processes
are only to be correctly interpreted when the inner
workings of the normal cell are understood, and
in but few instances can it be said that the
normal phenomena
are fully explained.
In the present article
it will be my object
to place before the
reader a few of
the more modern
ideas with regard to
the structure and
function of the cell,
and to try and ex-
plain the reasons
why a normal cell-
unit when subjected
to morbid influences
should have its life-
cycle so profoundly
altered as to produce,
either in the indi-
vidual cell or cell-
aggregate, signs of
obvious functional
derangement.
At the outset, it
should be remem-
bered that a typical
cell, whether animal
or vegetable, is made
up structurally of at
least four parts (see
Figure 14) viz. : —
a. The cytoplasm.
b. The nucleus, an
oval or spher-
oidal body situated somewhere in the cyto-
plasm.
c. The plastids, small living structures concerned
with the manufacture of various foods in the
cell.
d. The vacuoles ; these are spaces filled with fluid,
usually a watery solution of salts, certain pro-
teins, organic acids,sugars, and so on (cell-sap).
The cytoplasm, nucleus, and plastids constitute
TTL
Figure 14.
Diagram of a typical cell (stained with nuclear and plasmic stains)
a. Cell wall: not always present ; ect. Ectoplasmic layer of cytoplasm : this is often present
in plant cells; s/>. Spongioplasinic network of cyptoplasm, upon which minute granules or
" microsomata" are to be seen ; hy. Hyaloplasm; g. Granules, either of the nature of
zymogen-granules or Altmann's (see text) ; 6. Vacuoles ; f>I. Plastids ; M. Metaptasm
granules (starch, protein, etc.); k. Kinoplasm ; w. Nucleus showing (/) clear nuclear plasm
(rV) Linin network (in) Chromatin-granules and Karyosomes (iv) Plasmosomes or nucleoli,
the whole surrounded by the nuclear membrane. c. The centrosome (doubled).
the protoplasmic portions of the living cell or proto-
plast : the cytoplasm is often, especially in vegetable
cells, surrounded by a firm cell-membrane composed
either of carbohydrate material (cellulose) or of a
rather firmer protoplasmic substance derived from
the outer part of the cytoplasm (ectoplasm). The
animal cell is, however, rarelv enclosed by a complete
cell-membrane, and this membrane, when present, is
never composed of cellulose.
In its elementary
structural details, as
put forward above,
there is very little
difference between
the plant and the
animal cell ; but in
ultimate function
there are often very
marked differences,
the most well known
of these being per-
haps those connected
with the presence in
the plant cell of the
chloroplasticls, the
small oval protoplas-
mic structures which
contain the green
pigment chlorophyll.
The chloroplastids
are thus able, by
virtue of their pos-
session of this pig-
ment, to utilise a
portion of the radiant
energy of white
light, and to turn
this energy to ac-
count in furthering
the decomposition of
carbon dioxide and
water by the plastid,
the ultimate result
being the formation, by means of chemosynthetic
reactions, of some form of sugar (probably dextrose).
The animal cell rarely, if ever, possesses chlorophyll;
and in those instances where chlorophyll-containing
bodies are found in an animal cell (Hydra, Euglena
and other Flagellata), these almost always turn out
to be members of the Volvocaceae which appear to
be living in symbiotic connection with the animal
cell. This being so, the animal cell is not able by
January, 1913.
KNOWLEDGE
the latter enclosing as a rule one or more vacuoles
filled with fluid contents. This distinction into outer
and inner portions is not to be made in every cell,
since very young cells of embryonic tissues appear
during life to be almost entirely, if not quite, filled
with a mass of homogeneous living substance, in
which the nucleus and some granular structures are
suspended.
Later observers, notably Nageli, Schwann, Flem-
ming, Cohnheim, Biitschli, Heidenhain, and many
others have attempted to explain the structure
brought out by " fixing " living cells rapidly by
means of such substances as osmic acid, chrom-
osmium acetic acid, alcohol-formalin-acetic acid, and
others, upon the lines that the appearances produced
by these reagents represent the true living structure
of the cell-protoplasm ; some of these appearances
are.no doubt, correct representations — as,forinstance,
the fixation of the vacuoles in the cytoplasm, and the
chromatin-network in the nucleus; but others are at
least of doubtful significance, and the present-day
cytologist hasto guard very carefullyagainst mistaking
an " artefact " in the cell for the true structure. One
conception as tocytoplasmic structure which, although
open to considerable criticism, is, nevertheless, pro-
visionally accepted by many workers at the subject,
is that which gives to it a reticular basis or
ground-substance of fibrils, the so-called spongioplasm,
in the meshes of which a more fluid portion, homo-
geneous in appearance, the hyaloplasm, exists; it
cannot be denied that even in the living cell, in some
instances, a fibrillated appearance is to be seen in
the cytoplasm, and this persists and becomes more
pronounced after fixation, t
Another hypothesis which at one time appeared
likely to gain ground was that put forward by
Biitschli, who considered that cytoplasm might
possess an alveolar or froth-like structure, the spaces
in this being filled with liquid ; certainly the egg-
cells of certain animals, notably A scaris and Asterias,
possess a cytoplasm which suggests strongly the
alveolar structure, and cells of the nephridia of
Lumbricus and the Leech show a typical froth-like
appearance. But on the other hand there are many
cells the cytoplasm of which conforms more closely
to the reticular type ; and in the case of certain
large nerve-cells in the spinal cord and brain it has
been shown by Cajal and Bielchowski that a very
fine system of fibrils, the so-called neurofibrils, can
be brought into evidence by a process of treatment
with nitrate of silver and subsequent development.
These neurofibrils were also shown to extend into
the axis-cylinder process (axon) of the nerve-cell, as
well as into the processes known as dendrons.
The granules seen in protoplasm are nowadays
considered to be very important structural elements,
* It has been shewn that the Flagellata probably represent a sort of connecting link between the vegetable and the
animal kingdoms.
I See "The Vegetable Cell," by Hugo von Mohl, translated by Professor Henfrey. 1854.
I Mention must be made, in this connection, of the experiments carried out by Hardy with colloids (such as various mixtures
of gelatine and water) which pointed to the similarity of cytoplasm in physical constitution, to the " solid within a liquid "
type of gelatine hydrosol,
its own efforts to make use of the carbon dioxide
existing in the surrounding medium (atmosphere or
water), and in the majority of instances receives its
raw food materials in the form of complex carbo-
hydrate and protein compounds, the former of which
have already been built up for it by the vegetable
cell ; the latter, perhaps by the vegetable cell, but in
many cases by other animal organisms. The above
elementary physiological processes in a cell serve
to partially distinguish between the character of
the functions of vegetable and animal protoplasm,
although, as was pointed out, there may be no
structural distinction ; moreover, the explanation of
such variation in function must be looked for,
not in structural distinctions, but in the gradual
changes taking place during evolution from the
plant to the animal type,* changes, which,
although undoubtedly existent, still remain more
or less unexplained.
With regard to the structure of the several parts
of the cell noted above, it will perhaps be best to
take these in order, and consider some of the hypo-
theses which have been advanced with respect to
their ultimate physical constitution. I do not pro-
pose to go into the consideration of the chemical
composition of protoplasm, as this somewhat
undecided question is one which is likely to lead
the reader too far afield, and, moreover, might have
the effect of confusing his mind as to the object
of this article, viz., the conception from a purely
biological point of view of cell-structure and function.
(a) Structure of Cytoplasm.
Early conjectures as to the internal structure of
cell-protoplasm were not of such a nature as to
enable much criticism, seeing that the methods then
in use for " fixing" cells and for staining their con-
stituent parts were hardly adequate to bring out
many structural details ; moreover, the microscope,
at the period when Hugo von Mohl made his inter-
esting discovery of the " primordial utricle " in
vegetable cells, was not the high-class instrument it
is nowadays. Nevertheless, many interesting and
accurate observations were made at that time, more
especially in connection with the composition and
structure of the cell-wall. t
Protoplasm was at that period looked upon as
being quite homogeneous in physical constitution,
and it is only fair to state that there are many
nowadays who have come back to this view ; it was,
however, soon found that such a conception must be
modified, in that, in many living cells, notably Amoeba,
Aethalium, and numerous plant-cells, the main
cytoplasm was found to be made up of a clear outer
part, the ectoplasm, and an inner portion which was
granular and in some cases reticular, the endoplasm,
10
KNOWLEDGE.
January, 1913.
and many of them are undoubtedly of cytoplasmic
origin (microsomata) ; a few of them are capable of
taking on certain stains, such as " neutral red " in
the living cell prior to any fixation, and after fixation
at least four types of granule may be distinguished
according to the manner in which these structures
stain. Thus there are to be found the so-called
neutrophilic granules (see Figure 15) staining with
neutral dyes (neutral red), the oxyphilic type (see
Figure 16) staining with acid dyes such as eosin
and acid
b a sip hilic
Figure 17),
deeply with
stains such
blue ; and
times to be
phoph i I i c
staining
an acid or a
Many of the
ules seen in
plasm are, of
course, to be
p 1 a c e d
amongst the
category of
" metaplasm,'
granules of
protein, and
fuchsin, the
granules (see
which stain
alkaline
as methylene
there are at
found am-
g r a n ules
with either
Figure 15.
A polymorphonuclear
neutrophile leucocyte from
human blood, showing mi-
nute neutrophilic granules
(represented too large in
figure).
basic
larger
the
dye.
gran-
c vto-
FlGURE If).
A coarsely granular oxyphile
leucocyte from human blood.
pellicle,
these being the various
reserve food (starch,
so on), and the plastids
are naturally quite distinct from the
small elementary structures noted
above.
The Microsomata* mentioned above
usually exist upon the reticulum of
spongioplasm (where this can be
definitely stated to be present) and
stain as a rule with the acid dyes; the other
granules described are usually small rounded bodies,
varying in size from a quite distinct particle to a
fine granular appearance in the cell, the ultimate
granules being very indistinct (neutrophile type in
certain leucocytes). Such granules are, as a rule,
found scattered throughout the cell without any
definite relation to the spongioplasm network.
Another type of granule remains to be mentioned,
and that is the one first described by Altmann
(Altmann's granules) ; these, which stain with
acid stains (acid fuchsin) after special treatment
with other reagents, are found in all animal and
plant cells with the exception of the ovum, the male
germ-cell, and cells forming cancerous growths.
They are assumed to possess an important role in
the cell economy ; but the precise nature of their
function is, I believe, still sub judice.
Some of the granules mentioned above are looked
upon as possessing the capacity of manufacturing
enzymes in the cell, or may be the actual precursors
of the enzyme themselves ; the granules seen in the
*The Microsomata are, it appears, chiefly concerned in the production of the cell-wall in plant-cells, a process akin
secretion going on, which results in the deposition of cellulose.
+See " Knowledge and Scientific News," August-September, 1909.
secreting cells of many glands, both in animals and
plants, are known to be zymogens and these granules
may be seen readily in the living cell. But the
function of many of the types noted is by no means
settled, and the study of them is perhaps one of the
most important branches of cytological work which
is being carried out at the present time in biological
laboratories.
(h) Structure of the Nucleus.
I have had occasion before in this magazine to
describe the structure of the nucleus in connection
with the mechanism of nuclear division, + and since
writing the article in which this occurred have
made further observations upon nuclear structure.
The results have gone to confirm the generally-
accepted description of the constitution of the
nucleus, viz., that this bod}' is to be looked upon as a
spheroidal space limited externally by a firm mem-
brane formed, in all probability, of altered hyaloplasm
(kinoplasm), this space being filled with clear
nucleohyaloplasm, suspended in which latter is a
network of linin, and in the resting
nucleus the granules of chromatin
are arranged upon this network at
somewhat irregular intervals (see
Figure 18). With regard to the
presence of a nuclear membrane, a
somewhat controversial point, the fact
that the nucleus moves bodily along in
the endoplasm during the phenomenon
of " rotation " in the living assimilat-
ing cells of plants {Vallisneria , Elodea ,
and so on) without any alteration of
shape, seems to point to the possession
of an external firmer delimiting
quite distinct from the
cytoplasm of
the cell. The
nucleoli (plas-
mosomes) ap-
pear also to
have an exter-
nal skin, within
which the fluid
parts of these
bodies is con-
tained.
Further re-
search by cyto-
logists has
pointed to the
presence of fine
fibrils passing
from nucleus to
nucleus in adjacent protoplasts; it will be remem-
bered that distinct intercytoplasmic connecting
bridles have long been demonstrated passing between
adjacent cells (Gardiner and others : see Figure 19)
Figure 17.
A coarsely granular basiphile leuco-
cyte from human blood (very rarely
found.)
[Note. — This and the previous two figures are
from coloured diagrammatic drawings from a
hlood film made by the author.]
January, 1913.
KNOWLEDGE.
11
and the demonstration of an internuclear connection
is certainly an interesting point.
It is noteworthy that in a few instances the
chromatin constituent of the nucleus takes, in place
of separate granules, the form of a so-called
" permanent spireme " suspended in the nuclear
plasm ; the chromatin in these cases takes the shape
of small discs, placed end to end quite close together.
The permanent spireme is best seen in the cells of
the salivary gland of the larva of Chironomus. At
times, also, the chromatin granules become split into
two and even in the resting nucleus a spireme may
be seen made up of two parallel bands of granules,
an arrangement which is obviously of value when
karyokinesis takes place, since the earlier stages of
the prophase are eliminated.
With regard to the changes taking place in the
structure of the nucleus during mitosis, reference
may be made to the article mentioned above (see
footnote on page 10) ; these changes indicate, in the
main, an increase in the chromatin, a relative decrease
in the para-chromatin (nucleolar material) and loss
of the nuclear membrane. The latter change is
important since, if the membrane persisted, the
movements of the chromosomes to opposite poles
of the cell would be prevented ; this, then, is further
evidence of the presence of a membrane in the rest-
ing condition of the nucleus. [The question of the
centrosome is one more directly connected with
nuclear division, and will not be gone into here.]
(c) Structure of the Plastids ; Outline
of their Function.
These small bodies, many of which contain pig-
ment (chromoplasts) and others being colourless
(leucoplasts) have a structure which appears to
repeat in some respects that of the nucleus; but
there is no nuclein constituent in them comparable
to the chromatin of the nucleus. In the main, each
plastid appears to possess an outer membrane, and
internally, either a clear fluid part, or, as some
observers state, a groundwork of fibrils (spongio-
plasm) in the meshes of which is a clear, more fluid
portion; it is the latter which has dissolved or
suspended in it the pigment, when this is present
(chlorophyll, xanthophyll, carotin, and so on).
In many cases the plastids contain starch or oil in
their substance, this being evidence of the secretory
function of these bodies, and it appears probable that
these stored substances are formed by an actual
breaking down of the protoplasm of the plastid with a
subsequent re-construction of the starch or oil. The
function of the pigment chlorophyll has already been
touched upon (see page 8), but it should be
borne in mind that in the colourless plastids (leuco-
plasts) found in the cortical cells of subterranean
stem-structures and roots, the starch is formed from
the circulating sugar brought to the cell without the
intervention of the photosynthetic process, the
necessary energy for the secretory reactions being
derived from other sources than white light.
Fats and oils occurring in the so-called elaioplasts
are formed in much the same manner ; but, of course,
oxidation is at times incomplete and a hydro-carbon
is sometimes formed in place of a carbohydrate.
{d) The Vacuoles.
The modern conception of the vacuole has been
elaborated considerably of late years ; in fact, ever
since the importance of the biophysical phenomenon
of osmosis in the cell was recognised. The fluid
contents of the vacuole in the plant cell always possess
one or more of the organic acids in an amount
sufficient to set up osmotic currents between the
fluid in the vacuole and the medium surrounding
the cell, with the result that in many instances water
and salts are drawn into the vacuole according to
the needs of the protoplast.
Observations upon the origin and growth of the
vacuole have determined the interesting fact that
directly a vacuole becomes visible, the fluid contents
become surrounded by an extremely delicate pellicle
of ectoplasm (hyaloplasm), and many investigators
have looked upon the formation of the vacuole as
being akin to that of a plastid— vacuoles being some-
times known as tonoplasts (De Vries) in that they
govern the relative turgidity of a cell. The pellicle of
ectoplasm of the vacuole, the endoplasm, and the layer
of outer ectoplasm of the protoplast together form a
membrane, which, in the opinion of most biologists
nowadays, is of great importance in the process of
absorption by the cell of water and salts in solution ;
the so-called "selective capacity" of a root-hair, for
instance, being largely due to the presence of the
three living layers surrounding the vacuoles. The
physical laws governing osmosis naturally come into
play during the process of absorption, and the
amount of saline constituents entering the cell
depends largely upontherelative " osmotic pressures "
exerted, on the one hand, by the osmotically active
substances (organic acids, chiefly) in the vacuoles,
and on the other by those outside the cell. It will
be seen, then, that the vacuole governs the process of
absorption of raw food-materials ; but it must be
borne in mind that osmotic processes also govern in a
cell-aggregate the distribution of circulating " food "
(elaborated food) such as sugar, soluble proteids, and
the amido-acids ; all these substances are attracted
to those living cells in need of them for purposes of
construction, and here again the organic acids which
possess a relatively high osmotic power are probably
the determining factors in this attraction. The two
processes, then, both absorption of raw food-materials
and circulation of elaborated food, are dependent
partly upon purely physical influences and partly
upon the regulating action of the cytoplasmic mem-
branes in the cell.
The "Bioplast" or "Pangen" Hypothesis,
as a Biological Conception.
The hypothesis that the various structures met with
in the cell are all ultimately derived from a common
elementary body, the so-called " bioplast " or
" pangen " is one which for some time now has
occupied the attention of biologists. It argues that
12
KNOWLEDGE.
January, 1913.
any part of the protoplast may be, according to the
needs of the cell, transformed by chemical processes
into any other, and the most striking instances in
support of this hypothesis are, perhaps, to be seen in
the origin of the plastids from
the cytoplasm, and in the
formation of zymogen gran-
ules from the living substance
of the cell. Although this
conception is open to consider-
able criticism, it is one which
has to be taken into account ;
for it is well known that the
protoplast, both animal and
vegetable, is capable of a
certain degree of adaptation
to changed conditions of exist-
ence, and that structural
variations in the cell are by no
means uncommon under these
changed conditions. The
hypothesis, then, seems to be
provisionally a sound one, but
requires more discussion before
it can be placed in the category of the more definite
biological conceptions of the cell ; more than this
cannot be said at present, owing to lack of evidence.
Certain Problems Con-
nected with Cell-
Metabolism : The
Probable Causes of
Perverted Metabol-
ism: Reaction of
the Protoplast to
Poisonous Substan-
ces and the Various
Types of Irritant.
Some of the most interest-
ing cell-problems are those
relating to the unorganised
ferments or enzymes manufac-
tured by the cytoplasm, and
the question of certain sub-
stances which are produced
in the cell consequent upon
irritation by the presence of
bacteria or morbid influences
in the immediate vicinity of
the cell. The enzymes ap-
pear to be protein-like bodies
which have a remarkable
action upon (a) Carbohy-
drates, (b) Proteids, (c) Fats
and (d) Glucosides, existing
in the cell ; the main factors
in their action upon these
bodies seem to consist in a
process whereby water is first
of all synthesised with them to form a somewhat
unstable compound, and subsequently this com-
pound is broken up again, with the result that
several simple substances are formed, some of
Figure 18.
A Photo-micrograph of the definitive nucleus
in the embryo-sac of an Angiosperm {Helle-
borus niger) to show the nuclear membrane,
chromatin, reticulum and one large nucleolus
(to the left is the nucleus of the egg-cell).
(including also the
Figure 19.
A Photo-micrograph of a single cell of the Endo-
sperm in the embryo-sac of an Angiosperm to show
(on the left side) bridles of cytoplasm passing
through the cell-wall to an adjacent protoplast.
Note the oval nucleus with several nucleoli.
which are capable of being directly utilised during
cell-metabolism for constructive purposes. The
manner in which the enzymes are produced from
the zymogen-granules is not as yet fully understood;
it appears that the zymogen
may be converted into the
enzyme in certain cases by the
action upon the former of a
dilute acid or alkali, and that
the production of zymogen
in the cytoplasm is of a con-
structive (anabolic) nature,
whereas the conversion of
zymogen into ferment belongs
to the destructive (katabolic)
type of reaction.
Again, it is now well-estab-
lished that in the case of the
so-called organised ferments
(Saccharomyces, B. hutyricus,
B. lactis and so on) the actual
enzyme is a product manu-
factured in the actual yeast
cells and bacilli, and then
passed out of the cells into the surrounding
medium ; many of the toxins and toxic proteids
so-called toxalbumoses are of
this nature, otherwise known
as intracellular toxins ; but in
certain cases, as, for instance,
when bacteria gain entry into
the tissues of the animal bod}-,
the actual cells of the tissue
may react in a special manner
and produce anti-toxins which
tend to limit the production
of toxins by the bacteria, or
else neutralise such toxins.
Of late years two other
types of enzyme have been
shown to exist in the cell in
some cases ; these are the
oxidising and reducing en-
zymes (oxidases and reduct-
ases) and they have been found
to be present in many plant
cells. The oxidases are
capable of furthering the
oxidation of the cytoplasm in
the absence of free oxvgen,
and it appears that the instan-
ces of so-called anaerobic
respiration (certain bacteria)
are due to the presence of
some form of oxidase.
The question of proteid-
metabolism in the cell is a
problem which still remains
largely unsolved ; it seems,
however, to be established that one of the inter-
mediate stages consists in the combination of
three classes of bodies, viz., the amido-acids, some
form of carbohydrate, and a sulphur-compound; but
January, 1913.
KNOWLEDGE.
13
the formation of the amido-acids themselves is a
complex process. In the plant-cell in some cases, as
was shewn by Pfeffer, it appears that calcium nitrate
is decomposed by oxalic acid, nitric acid being set
free and utilised in the formation of more complex
nitrogenous compounds, and it seems that at times
hydrocyanic acid may be used in the same manner.
Living protoplasm is constantly undergoing a
series of oxidative and reconstructive reactions, and
it is quite impossible to make a sharp line of distinc-
tion between the so-called anabolic and katabolic
processes going on in the living substance ; these
two types of reaction are always going on hand in
hand, and we must look upon the protoplasm as
being the seat of a large number of oxidative and
constructive processes, some of which are always
going on ; others, such as those concerned with the
storage of food-substances (proteid, carbohydrate or
fat), taking place only at certain periods, depending
to a large extent upon the needs of the organism at
the time.
It will be seen, then, that normal metabolism is a
highly complicated series of interactions between
various compounds in the cell; when the nutrition
of a cell is modified in any way, either in quantity,
quality, or both, the protoplasm is certain to react in
some special manner to the changed conditions.
Nutrition may be so profoundly modified that the
cell may not be able to earn- on any kind of
metabolism, whether proteid, fat or carbohydrate,
and in such a case function will be stopped or at
least suspended. In many instances, when the
medium surrounding a cell contains substances which
act adversely upon metabolism (toxins, alkaloidal
poisons, and so on), the protoplasm will not react in
a manner adequate to cope with surrounding
conditions, and subsequently the noxious substances
gain the upper hand, the living substance passing
into a condition known as "fatty degeneration";
this must be distinguished from true "fat metabolism"
in the cell, since in the degenerative process no
reconstruction takes place as in the normal cell.
Less virulent irritants acting upon the cell over
long periods of time (chronic irritation) may, in the
long run, produce marked changes in metabolism,
and cells in which such perversion of normal
metabolic processes has taken place may, if carried
from one part of an organism to a remote part, set
up similar perversions in the cells amongst which
they settle. It seems, in fact, that once the cycle of
metabolic changes in a cell has undergone a complete
alteration, a cell is able to influence others in its
immediate vicinity ; it is possible that a substance or
substances of the nature of toxins (cytotoxins) or
enzymes may be produced which have a profound
effect upon normal metabolism.
As evidence of the power which small quantities
of certain substances have when distributed through-
out a cell-aggregate, the various internal secretions
manufactured in the animal body may be taken ;
there is no doubt nowadays that the thyroid gland,
the suprarenal capsules, the islets of Langerhans in
the pancreas, and the ovary manufacture internal
secretions which are of immense value to the cells of
the bod)- in aiding the furtherance of normal
metabolism, since, when any of these internal
secretions is absent or produced in excess, it is found
that metabolism is profoundly altered. The internal
secretions formed in these bodies are in most cases
protein substances, some of which are possiblv akin
to enzymes in their action ; but their constitution is
in many cases obscure, although their physiological
action is definite enough in a few instances.
The above brief considerations will enable the
reader to grasp the fact that the cell possesses a
highly complex organisation, and that the processes
going on in the protoplasm are of such a nature as
to call upon our keenest powers of observation and
experiment for the purpose of their elucidation : and
it will have been gathered that not one of the least
remarkable features in connection with cytological
phenomena is the infinite capacity of the living cell
to react to stimuli of varying nature, and to adapt
its metabolism to altered external conditions.
GLOW WORMS AND LIGHTNING.
By ROBERT W. PETHEN.
The common glow worm (Lampyris noctiluca) is a
most interesting member of that large order of
insects, the Coleoptera, and before proceeding to
describe how I found this insect to be susceptible to
the influence of lightning, I would like to make a
few observations on its light-giving capabilities as
shewn by the perfect female and also by the same
insect when in the larval stage.
It may not be out of place to mention here that
the glow worm gives forth a greater or lesser amount
of light in every stage of its existence, including the
egg, which "glows" more or less brightly when
moistened with water and held in a dark place.
The beautiful phosphorescent light displayed by
this little beetle is far more familiar than the insect
itself, and although the female is popularly credited
with being the cause of the twinkling lights to be
seen amongst the grass and hedge-banks in certain
14
KNOWLEDGE.
January, 1913.
favoured localities during the summer months, this
is not always the case.
I have proved by actual experiment that the larvae
have the power of emitting light from the moment
that they leave the egg.
As the young larva increases in size, so the light-
giving area of the anal segments becomes larger and
also brighter, so that it is at times almost
impossible to tell whether the light in the grass
proceeds from a larva or a perfect female.
If the light of a full-grown female larva be closely
compared with that of a perfect female, the
former will be found to be smaller and also of a
more greenish colour.
With regard to the duration of the light there is
also a decided difference ; for the light of the perfect
female may continue to shine steadily for several
hours when undisturbed, i.e., from dusk until 1 a.m.
or even an hour or so later; whereas in the larval
form it is seldom that one finds the light shining
continuously for more than a few minutes.
Glow worms, like ants, are very sensitive to vibra-
tion, and when approaching them in the grass one
must not tread heavily, or they will extinguish their
light and thus be lost to view.
This applies to the larvae as well as the perfect
females.
If you pick up a female glow worm and turn it
about in your hand, it feigns death and its light
remains extinguished until all apparent signs of
danger are past. Whilst it is still in the larval form,
this insect behaves in quite a different manner under
similar circumstances ; for when turned about in the
hand, it generally lights up at once, the light
gradually dying away, but reappearing again and
again as often as the insect is disturbed. It will
light up in the same manner if the glass or box, or
other vessel in which it has been placed, is smartly
tapped with the fingers.
The glow worm larva will also give forth its light
if it is sprinkled with cold water, or suddenly
immersed in the same, while it is also apparently
influenced by the effects of lightning, as I venture
to think the following particulars will prove.
For several years I have been working at the life-
history of the glow worm, and with this object in
view I had, at the end of July, 1911, about a
hundred and fifty larvae of L. noctiluca, all of them
having been hatched between June 23rd and July
27th of that year.
These larvae were fairly evenly distributed in four
glass tumblers. Each glass had a closely-fitting lid
made of cardboard and fine wire gauze, and also
contained a small moistened root of grass.
The four glasses containing these larvae were kept
on the shelf of a hanging book-case in our sitting-
room, in a rather dark corner about seven feet above
the floor, and near a window facing east.
These tiny larvae would give forth a very small
spark of light, if they were disturbed by tapping on
the glasses, or even by tapping the shelf on which
the glasses were kept.
On the evening of July 29th, 1911, we had a
storm with thunder and much lightning, and as I
happened to be at home, I thought I would see if
the lightning had any effect on the larvae; having
previously read a brief account* stating that glow
worms were affected by it.
For an hour, from 8.15 p.m., when the lightning
flashes were very frequent, I kept the larvae under
observation. The unusual amount of electricity in
the air certainly appeared to effect these larvae, for
tiny bright greenish lights kept appearing and dis-
appearing from first one glass and then another,
right throughout the time that I was watching them.
Occasionally there would be lights showing in all
four glasses at one and the same time, when from
six to twelve distinct points of light could be seen ;
at other times there would be only three or four
lights visible.
No doubt many more of the larvae were affected
in a similar manner; but their light would be hidden
by the intervening roots and blades of the grass,
amongst which they were generally to be found.
None of the flashes of light lasted more than a
second or two, and they were all produced without
any mechanical disturbance of the larvae.
The window was partly open, and although the
hour was not very late, the corner of the room where
the larvae were kept was dark enough for their
lights to be clearly seen. The lightning had not
ceased at 9.15 p.m. ; but as we lighted the lamp at
that time, the display of miniature fire-works could
no longer be seen.
I watched and waited on many evenings after-
wards, to see if the display would be repeated under
normal weather conditions, but without result.
On the 19th of the following month (August,
1911), however, there was another storm in the
evening with lightning, and the glow worm larvae
acted in exactly the same manner as they did on the
29th July.
Unfortunately, I was prevented from making any
further experiments in this direction, owing to my
glow worm larvae all gradually dying off during last
autumn and winter.
At the present time I ha^ve several hundred fresh
larvae, hatched during July and August, 1912 ; but
the warm thundery weather suitable for carrying out
further experiments in this direction is still lacking;
and here I will leave the matter for the present.
See Nature, October 1st, 1903.
AN "IDEAL" MUSEUM AND ITS GUIDE.
By A PROVINCIAL CURATOR.
On the principle that there are those who step in
where angels fear to tread, I am venturing to refer
to the very latest in the way of museums, namely the
new London Museum, and its Guide.
Probably no museum ever came into being with
such a nourish of trumpets as the new museum at
Kensington Palace. The illustrated papers have
given picture after picture of the museum's contents,
or its curator, and have thus shown to an admiring
world photographs of this, that, and the other object,
scores of better examples of which are to be found
in the many other London Museums, and even in
provincial collections.
But I do not wish to deprecate the sweet uses of
advertisement as adopted by the new museum. In
fact, all admire its methods. And no doubt even our
national collections would benefit if their recent
additions were duly reported, described, and figured
in the papers. But from illustrated interviews,
special articles, pictures of people holding pots, and
other items that have appeared in the daily and
weekly press, it is clear that the museum is on
extremely new and up-to-date lines. We are told
that there are no headaches in the new museum !
No confusing labels. Everything is simply and pro-
perly arranged, so that he who wishes may read the
story of the city's growth and greatness from the
time when the pool of London was wallowed in by
men with oakum-covered arms and legs (such as
shown in the museum " Annexe ") to the time when
a similar individual, bereft of his oakum, but in a
boiled shirt, sits in a " Handsome " cab. And we
learn that as the visitor flits from case to case a
panoramic view of London's history is presented to
him. And thus for the first time, so 'tis said, a visit
to a museum is to be both pleasant and profitable.
The curator and his assistants (we learn from the
official "Guide"), are " luckily unhampered by the
entangling meshes of red tape " and have conse-
quently " achieved results which would have taken
ordinary officials, less fortunately circumstanced,
years to carry through." It is, perhaps, as well that
there is no red tape, or the " author " would certainly
not have been permitted to advertise his private
literary ventures on the cover.
Being among the " ordinary " officials, and at all
times anxious that the long-suffering ratepayers, who
pay for my golf clubs and send me to conferences,
should get the greatest possible benefit from the
collections under my charge, I paid two visits to the
new Museum, in order to derive inspiration from the
work of its, presumably, "extraordinary" officials,
and I paid a shilling for its " Guide " ; but I only
did that once ! I was anxious to see this ideal
museum, with its perfect classification, and its lack
of red tape. I wanted to see (quoting from the
guide book) " the palpable and material object
lessons, more likely to impress the mind with the
realities of the life of London in the olden times,
than reams of dry sociological theories, learned
historical disquisitions, and pompous moralising
tracts." (To grasp the full import of the last
sentence, it should be read three times!)
There is another paragraph in the guide which
appeals to the provincial curator: — "Many private
individuals, moreover, have generously come forward
and presented their laboriously garnered stores
("laboriously garnered stores"!) illustrative of
London's manufactures and arts, in order that these
cherished treasures of theirs may become the heritage
of their fellow Londoners — in being and yet to be I
Others have munificently provided the funds
requisite to enable the Trustees to acquire
collections, unequalled in their completeness, of
ancient costume, armour, weapons, pottery, glass,
porcelain, enamels and silver ! This " unequalled in
their completeness " is pure piffle. The "author"
(as he styles himself) of the Guide can never have
been in the British Museum, The Victoria and
Albert Museum, The Tower, The Wallace Collec-
tion, The Guildhall Museum, and many others not
very far away : or if he has, he must have been
" blind," in some way or other.
On my first visit it was raining, and I had an
umbrella. This had to be left at the cloak-room,
which was in another building some distance away,
•and the ticket I got in exchange was not large
enough to keep the rain off while I walked back to
the museum, and back again for the umbrella when
I had seen it. I felt relieved that there were no
" entangling meshes of departmental red tape " here,
or I should probably have had to run round the park
in my shirt.
On my second visit the weather was fair, so I was
not requested to walk across the garden to leave my
umbrella, but could carry it with me where I would !
As I entered the building I found two ways to the
stairs ; a wide one, open and free, and a narrow one,
barred by a piece of wood — I believe polished oak
— possibly to illustrate the kind of trees that once
grew in London. I naturally went through the
wide opening, and was going up the stairs when a
policeman seemed to drop from an aeroplane or
somewhere, hauled me back again, and made me
push my frail form against the bar of oak, which
proved to be a species of turnstile. I don't know
what it registered me as, but doubtless, judging from
the published numbers of visitors, a " large party."
I obtained my first object lesson before I had
reached the top of the stairs. In order to inform
visitors to "keep to the right," the best way is to
hammer a nail into the middle of a large old oak
panel, and hang a placard up on it. But upstairs,
all my fondest hopes and anticipations fled. I found
15
16
KNOWLEDGE.
January. 1913.
a number of rooms, of varying sizes, each crammed
with as many mid-Victorian funereal exhibition cases
as it could hold, and each case similarly crammed
with as many specimens as possible. But each
absolutely without any attempt at classification or
arrangement. Even the rooms were not set apart
for definite purposes, but similar objects were to be
seen in almost every room, and in many instances,
in several different cases.
By the press reports I was foolishly led to believe
that I should first see specimens illustrating London
in prehistoric times, then, step by step, through
Roman, Saxon, Danish, and other periods, down to
the present day. Nothing of the sort. Any object
of almost an}- date could be seen in almost any
room — nay — in almost any case ! It is quite possible
that the new London Museum is not unique in this
respect ; there may still be seen some musty
collection formed by a " Literary and Philosophical "
Society a century ago, in some old-world town,
which is similarly " arranged." But in such instances
the news is kept quiet. Anyway, it is not trumpeted
forth, east and west, south and north, that perfection
and classification lies here. And only of the new
London Museum can it be said that the specimens
are displayed (I am quoting now!) "Moreover, as
much with a view to scientific precision as with a
keen appreciation of the artistic effects of suitable
surroundings and grouping ; all, moreover (whenever
" moreover " appears, I am quoting ! ) with the ever-
present aim, not so much of instructing and
educating the public, as of arresting their attention
and stimulating their imagination — in a word —
interesting and amusing them."
I am not quite sure whether the curator, or
director, or keeper and secretary (who, by the way,
did not write the Guide) has tried to act up to this
ideal of amusing the public : but in some respects
he has certainly succeeded.
To an ordinary mortal (if a provincial museum
curator can be thus described) "classification"
implies that objects of a similar kind, or similar
period, are arranged together. Just as we should
expect to find cabbages in a greengrocer's shop,
trousers in a tailor's, and blouses at the draper's ;
so in the new model museum one might expect
to find the pre-historic objects together, Roman
objects together, mediaeval, and so on, all sorted and
arranged, and china in one case, enamels in another,
iron objects in another, coins in another, and so on.
Such a method is the very alphabet of classification.
But, instead, case after case is filled with objects
dating from pre-historic or Roman times to the
nineteenth century, and case after case with iron
objects, coins, pottery, embroidery, and so on, hope-
lessly and unaccountably jumbled. There is a good
collection of bellarmines, all similar in shape and
design, and of the same period, and all presumably
found in London. Yet one must examine about
fourteen different cases, and a mantelpiece or two,
in various parts of the building, if he wishes to see
all the bellarmines. Iron objects, such as knives
and daggers, are well represented ; but they are
scattered in different sections of different cases, in
different rooms. The china, enamels, embroideries,
coins and medals might be considered to be repre-
sentative, had one the patience or time to search for
them all, and endeavour to carry them in one's mind.
It can only be assumed that it is possibly the intention
to illustrate the various historical periods in each
individual case so that the visitor need not examine
them all, but simply stand in front of any one case
and then walk away with the history of London at
his finger tips.
In addition to the Palace proper there is an
" annexe," with prison cells, a Roman boat, a
wooden Ancient Briton, Adam's fireplaces, and
models of old London. This is arranged after the
plan of the maze in Hampton Court, and there is
quite an army of officials to push visitors the right
way each time they go wrong. An extraordinary
exhibition, and quite of a Madame Tussaud flavour,
is that of a model of Jack Sheppard, the thief and
robber, in his cell, apparently at dead of night, with
a lantern dimly burning. And dare I interject, for
the benefit of "the author," that even the name of
this great hero is spelt incorrectly in the guide ?
Still another building, a magnificent one that
might be used so well, contains half-a-dozen palm
trees and a " Handsome" cab. The number of people
who stop and read the brass plate, and examine the
cab, is astonishing, especially as probably many of
them found their way to the museum by taking a
seat in one.
I have already explained that I bought a guide. I
thought perhaps it would act as a key to the collec-
tions. It cost a shilling. One shilling. I presume
the price is arranged so that the Guildhall and South
Kensington Collections may soon be purchased from
the profits, and thus make the London Museum, the
London Museum indeed. Anyway, I am not the
first Northerner who has " Banged awa twa
saxpences " in London !
The cover is a brilliant danger-signal red, and in
the centre are the Royal arms, and " G.R." in large
letters, which the policeman told me stood for King
George, though he did not quite know how. On the
inside cover we are informed of the hours of opening,
the hours of closing, and that visitors are invited to
communicate with the author if they have any
suggestions to make ! As I was not spending my
holidays in the museum, I declined the modest
request, but hope to forward a cop}' of this paper to
him. There is no date on the cover of the guide.
There is a portrait of Queen Mary as frontispiece,
and the next page is dated 1912, so that one page at
any rate is up-to-date. There is an introductory
note (from which we have already quoted), then a
view of Kensington Palace and Gardens in the reign
of Queen Anne, and a portrait of the late Queen
Victoria at the age of eight. This is dated May
24th, 1819. Then follows a "preface" which is
dated May 24th, 1899, so that there seems to be the
same glorious uncertainty with regard to the date of
January, 1913.
KNOWLEDGE.
17
the publication of the guide that there is with regard
to the chronological arrangement of the specimens
in the museum.
It is also apparent that the writer of the guide has
some relatives who are oculists and opticians, who
will certainly have to be consulted by anyone trying
to read the pamphlet carefully.
On the title page we are told to "Notice" — "This
catalogue and guide are copyright, and immediate
proceedings in Chancery will be taken against any
infringers thereof." As our old friend Pooh-
Bah, F.L.A., would say, the punishment would
certainly fit the crime.
The guide is a fair model of what a guide
should not be. It is badly printed, with ancient
type, on poor paper. The details of the cases are
mixed up with the history of the Palace, and with a
catalogue of the pictures, and there is no index ; so
that it is really a difficult matter to find anything in
it. Many of the cases are not numbered at all, and
we read of Case No. (long), Case No. (side), Case No.
(centre), Case No. (side long), and so on. By the
words side, centre, side long, and so on, I presume
reference is made to the position of the various cases
in their respective rooms, but as I was unsuccessful
in identifying them, I cannot confirm this suppo-
sition.
An idea of the " scheme of classification " can be
obtained from the following particulars of the first
few cases, in which, if anywhere, an attempt at
order has been made: — Case 1, Stone Ages, Bronze
Age, late Celtic Period ; Case 2, Ceramic Art.
Case 3 (no heading at all ! but apparently con-
tains objects of the first to fifth century A.D.)
Case 3, "continued"! Saxon Period; then follow
" Relapse to Barbarism " (sic) ; Case 4, Early
Mediaeval Pottery; Case 5, Battle Axes, Swords, etc.;
Case 6, Wine Bottles ; Case 7, Lighting Appliances ;
Case 8, Prehistoric Mammalia, etc. (the "etc." in-
cludes all sorts of things that ought to be miles away).
Next is a " Green Coloured Bust ' (sic), which sounds
rather like a bilious attack ! and a " Bell in case."
Then Case 9, Mediaeval London, and so on to Case
12. A description follows of the " Queen's Closet "
and " Pictures of Old London," followed by " Nos.
20 to 34," which are apparently pictures. After all
this, oddly enough, is a heading in large type,
" London Museum Exhibits," and it calmly proceeds
to a list of the contents of Case 13. And the guide
ends up with " A condemned Cell, Old Roman
Galley, Mantelpieces, etc. ; Panoramic Models of
Old London, Lobby for various exhibits, Old
Jacobean Room." It was with some such expression
as " A condemned Cell " that I closed the " Guide,"
and thought of what might have been done with the
shilling. However, I will not say it is useless ; when
folded round, and fitted with a pill-box lid on the
top, it makes an excellent toy letter-box or money-
box, coloured red, and with G.R. on it already
complete !
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc., F.R.A.S.
OBITUARY. — The deaths of two well-known English
astronomers have occurred recently. Sir George Darwin, the
Plumian Professor, had been in failing health for some time,
though he was able to read in person his last paper (on a new
form of periodic orbit) to the Astronomical Society last
summer. His principal work was on the theory of the tides,
and their secular effects on the development of our system.
He was the originator of the view (still, I think, held by most
astronomers, though there are some important dissentients)
that the moon was formed by tidal disruption of the earth by
solar tides at a time when the rotation was very rapid, and
that the moon has acted as a brake on the earth ever since,
bringing the rotation to its present value, while the reaction
on the moon has caused its recession. He was the author of
a very useful popular treatise on the tides, which explains
the method of Harmonic Analysis, and shows how the tides
may be predicted for any port after a sufficiently long series
of records is available. His work on periodic orbits was an
investigation of the different paths a small planet might follow
under the action of the Sun and an imaginary large planet,
Jove, whose mass was one-tenth of the Sun's. This list of
his works only includes those portions which are of most
interest to non-specialists.
The death of Mr. S. A. Saunder, the Gresham lecturer, was
far more unexpected. He was taken ill during his course of
lectures on the Tides last October, but managed with difficulty
to finish them. Many of our readers must have heard his
lucid explanations of some rather difficult branches of
astronomy. He was a Vice-President of the Royal Astro-
nomical Society, and it was expected that he would before
long fill the Presidential chair. The astronomical work for
which he will be chiefly remembered was the accurate deter-
mination of the positions of a large number of points on the
moon, using the beautiful large-scale photographs taken at
Paris and in America. He found that the previously assumed
positions were much in error ; they had been made by measures
at the telescope from the limb ; he showed that it was far
better to get them from measures on the photographs,
provisional coordinates being first assumed for some leading
points, which could be afterwards checked and corrected by
the results. Accurate places of several thousands of points
were thus found, and by comparing their positions in different
librations it was possible to say which regions of the moon
were above the general level and which below it. He showed
that this was as difficult as finding the parallaxes of the
nearer stars. He was superintending the preparation of a
large map, on which the points measured by him were accurately
laid down, and the filling in of detail done from the photographs.
Mr. J. A. Hardcastle was associated with him in some of his
work, and gave much help in the measures.
THE ALBEDOES AND BRIGHTNESS OF THE
PLANETS. — Some photometric observations of the stellar
magnitude and albedo of the planets have been made with
the Draper Telescope at Harvard College Observatory. The
result for Venus at mean superior conjunction was — 2m-56
(thirty-four exposures on twenty-eight plates). The following
magnitudes are for mean opposition : — Mars, — 0m-57 (thirty-
seven exposures on thirty-six plates) ; Jupiter, — lm- 78 (twenty
exposures, nineteen plates); Saturn, +lm-52 (twelve plates).
The differences, photographic magnitude minus Muller's photo-
metric magnitude, are: — Venus, 4-lm-08; Mars, + lm-33;
18
KNOWLEDGE.
January, 1913.
Jupiter, + 0m-57; Saturn, + lm-23. The Sun being of
Spectral Class G, a difference of magnitude of 0m-98 would
be expected, and this would be greater for the planets, as
reflexion would tend to make the light redder. The deduced
photographic albedoes are: — Venus, 0-66; Mars, 0-15;
Jupiter, 0-80; Saturn, 0-53.
The very high value for Jupiter is noteworthy, and suggests
that a little of his light may be inherent, especially as some
portions of his disc are obviously dusky.
SATURN. — This planet has been in opposition in
November, and now that it is getting into considerable North
Declination it is attracting more attention from English
observers, especially as Mars and Jupiter are invisible. It is
most desirable that the disc should be searched for features
sufficiently distinct to determine the rotation period. This
differs very widely in different latitudes, from ten and a quarter
hours at the equator to 10h 38™ in the temperate zones; but it
is most desirable that these values should be checked by other
spots, and that it should be found whether the transition is
sudden, or whether intermediate values exist. Spots suffici-
ently well marked to be easily identified on their return are
not very common, and whenever one is seen it should be
utilised to the full, and notice telegraphed to the possessors of
large instruments.
Mr. P. Hepburn, the Director of the Saturn Section of the
B.A.A., gave some interesting notes in November, on recent
observations. A curious feature, confirmed by several
observers, was a dark shading on the ring along the planet's
limb, on the side opposite to the true shadow. This is a very
perplexing observation, and I have not yet seen any plausible
explanation. Mr. Hepburn also points out that careful obser-
vations should be made as to where the southern portion of
the planet's limb lies on the ring, relatively to its southern
edge and the Cassini Division. In this regard it should be
remembered that the dimensions of the ring used in The
Nautical Almanac do not include the latest measures, and
that their value of the polar semi-diameter of the planet is
faulty ; what they give is the value of the actual polar radius
as it would look if seen unforeshortened ; but what we
observe is a radius of the planet which is now twenty -four and
a half degrees distant from the pole, and therefore decidedly
longer.
LIMITING DISTANCE FOR HYPOTHETICAL
SATELLITES OF NEPTUNE.— Mr. C. T. Whitmell
recently gave me an interesting problem, viz., to find the
greatest distance at which a satellite of Neptune need be
searched for. Dr. G. W. Hill in his researches on the
Lunar theory, gave the elements of a satellite which had
1-7 lunations in the planet's year. The shape of the orbit
is curious ; its distance from the planet at Syzygies is only
one-third of that at quadrature, and when the motion is
referred to the line joining sun and planet (considered as
fixed), there are cusps at the quadrature points. In the case of
Neptune I find that such a satellite would be distant 0-30 astro-
nomical units from Neptune in syzygies and 0 • 87 in quadrature.
If the latter took place in opposition the satellite would appear
L7 degrees distant from Neptune. As there is little chance
of an actual satellite being so distant we may take one degree
from the planet as the limit of useful search. A good deal of
search has already been carried on by photography, but there
is plenty of room for further efforts. In the case of very
close satellites visual search would be more promising. All
the probabilities point to Neptune having other satellites, but
at such a distance only very large ones can be seen. Such
tiny bodies as Phoebe, the outer satellites of Jupiter, or even
(probably) the four satellites of Uranus would be beyond our
reach.
PROFESSOR FOWLER'S DISCOVERY OF A NEW
SERIES OF LINES IN THE SPECTRUM OF
HYDROGEN. — Four sets of lines arranged so as to form
regular rhythmical series were already known in the spectrum
of hydrogen. A few stellar spectra showed evidence of a fifth
series related to the fourth in a simple manner that suggested
that it belonged to the same element. The lines were,
however, much fainter than the others, and had not been
detected in the spectrum of terrestrial hydrogen. This Professor
Fowler has now succeeded in doing, taking the spectrum of
the gas in a low-pressure tube, mixed with a little helium.
He has not yet succeeded in getting the lines in the absence
of the helium, but their exact accord with the formula for the
fourth series, when one of the constants is halved, leaves
practically no doubt that they belong to hydrogen. His
paper was read at the December meeting of the Royal
Astronomical Society.
BOTANY
By Professor F. Cavers, D.Sc, F.L.S.
THE GENUS LEITNERIA.— In Engler's system of
classification the genus Leitneria, constituting the order
Leitneriaceae, is placed in a separate cohort (Leitneriales)
near the base of the Lower Dicotyledons (Archichlamydeae)
on account of its catkin-like inflorescence and simple flower
structure. The two species of Leitneria, confined to North
America, are shrubs with spikes of dioecious flowers ; the
male flower has from three to twelve stamens and no perianth,
while the female has a scaly perianth and one carpel with a
long style, the unilocular ovary containing a single ovule.
Pfeiffer (Bot. Gaz., LIIL, 3) has made a thorough examination
of the development of the flowers of this isolated genus, and
finds that the ovule contains a single archesporial cell, differing
from most of the Amentiferae or catkin -bearing trees in this
respect, though the same condition occurs in Bctula alba,
Alnus, and some species of Salix — hence a multicellular
archesporium can hardly be considered a group character.
The young embryo is pear-shaped, and has a massive
suspensor ; there is no fixed sequence of cell-divisions in its
development. The most striking features of Leitneria, how-
ever, are the resemblances which it shows to Gymnosperms;
but such resemblances are also found commonly among the
Amentiferae. The author's conclusion is that while the
morphology of Leitneria is not such as would make it possible
to place it definitely in any of the families of Archichlamydeae,
it agrees with the Amentiferae in suggesting the possibility of
the derivation of the lower Dicotyledons from Gymnospermic
forms with compound inflorescences.
DEVELOPMENT OF SALVINIA.— Few groups of plants
have been so much worked at as that containing the four
" water-ferns " or Hydropterideae, though it is now generally
recognised that the two families formerly classed together
under this name ought to be separated somewhat widely, the
Salviniaceae (Salvinia and Azolla) having probably arisen
from a homosporous family like the filmy ferns (Hymeno-
phyllaceae), while the Marsiliaceae (Marsilia and Pilularia)
are probably connected with the Schizaeaceae. The most
striking character of these two families is, of course, their
heterospory — they are the only ferns with two kinds of spores
— but they present many other interesting features. In a
recent paper, Zawidski (Beihefte zum Bot. Centralbl., Band
28, Abt. 1, 1912) gives an elaborate account of the development
of the vegetative organs and sporangial receptacles (sori) of
Salvinia nutans, clearing up various points and giving a very
complete picture of the morphology of this type. The growth
of the shoot takes place with great regularity ; the stem grows
by a two-sided apical cell, and soon shows differentiation into
nodes and internodes, each node showing four peripheral cells
which form the initials for the two floating leaves, the sub-
merged leaf, and the branch. All these organs grow by a two-
sided apical cell, and this is also the case with the sori, each
sorus being a metamorphosed segment of a submerged leaf.
The oldest sorus produces the large spores (megaspores), the
others produce the small spores (microspores).
MASSULAE OF AZOLLA.— In connection with the
preceding note, mention may be made of a recent paper
by Hannig {Flora, Band 102) on the development of the
massulae of Azolla. This plant is, like Salvinia, a free-
January, 1913.
KNOWLEDGE.
19
floating aquatic fern, but it has roots, not modified root-like
leaves, and its leaves are divided into two lobes, the upper
lobe having a small cavity inhabited by the blue-green alga
Nostoc. The spore-case groups (sori) are usually in pairs,
the microsporangial sori being much larger than the mega-
sporangial sori and the latter containing a single megasporan-
gium with a single spore. The mega-sorus of Azolla has
often been compared with the ovule of a seed-plant, theindusiuin
being likened to the integument of the ovule. One of the
most striking characters of Azolla is the presence of several
masses of frothy substance (massulae) in each microsporau-
gium, the massula having the microspores embedded in it
while its surface is covered with curious barbed hairs
(glochidia). The spongy massulae float about on the surface
of the water; the mega-sorus sinks at first, but eventually
decay of the indusium sets the spore free and it germinates,
producing a female prothallus which rises and floats about on
the water, becoming anchored to a floating massula by the
barbed glochidia.
Hannig has investigated especially the structure of the
massulae, and of the three curious floating-masses on the top
of the megasporangium which are formed in the same way as
the massulae. He finds that the substance (periplasmodium),
from which the massula material is formed, is derived from
the well-developed tapetum layer, the nuclei of which show
repeated division. These periplasmodium nuclei lie originally
just within the wall of the microsporangium, but later become
scattered through the protoplasm ; the periplasmodium
increases in volume, stores up starch, and produces a number
of vacuoles in which the microspores become enclosed.
Within these vacuoles there appears a fine foam-like network,
and from the surface of this foam there arise finger-like pro-
cesses which become glochidia, developing recurved hooks
at their tips. The periplasmodium is originally composed of
living protoplasm, but eventually the walls of the foam-like
structure become changed into cellulose, while the glochidia
walls are cutinised. Hannig also examined the floating-
apparatus of the megasporangium, and found that it is
developed in exactly the same way as the massulae in the
microsporangium ; he detected the thirty-one abortive mega-
spores as irregular yellowish inclusions in the meshes of the
floating- mass. He confirms the view of former investigators
that the unisexual sori of Azolla have arisen from an
originally monoecious condition.
MENDELISM AND PIGMENTATION.— The greater
part of the President's address to the Botanical Section of
the British Asssociation was devoted to a consideration
of the methods of Mendelian research, with special reference
to the chemical phenomena concerned in the production of
colour in flowers. The Mendelian method is analogous to that
of the chemist, who, given a complex mixture, sorts out the
ingredients and submits them severally to analysis. The
Mendelian analyst, given that complex mixture which is called
a plant or animal individual, sorts out the ingredients and
analyses them. The Mendelian analysis is made not by direct
but by indirect methods ; so long as the physical nature of
living substance remains unknown we can hardly hope to
resolve an individual into its physical components — all that
can be done is to make comparative analyses of individuals,
and discover how their several components differ from each
other. For this purpose one may represent the individual by
the equation, Individual = X + C, where C represents the sum
of the Mendelian characters, and X the imaginary or real
individual groundwork left after all the Mendelian characters
have been removed by analysis. The Mendelian method is
concerned directly with the resolution of C into its components.
Indirectly, it is also concerned with X ; for if the full value of
C be determined, that of X may be inferred. This concession
made, it is permissible to concentrate our attention on the
term C, and the business of the Mendelian is to resolve this
complex of characters into its constituent unit characters.
As the result of experimental analysis, Mendelism is enabled
to state the problem of the behaviour in inheritance of two
individuals in the following terms. The complex of character-
istics which distinguishes an individual is the expression of the
sum of a long series of characters. As the individual arises
from germ-cells, so each character arises from a germ within
the germ-cells — such germs of characters are called factors.
When two germ-cells unite to form an incipient individual, or
zygote, they bring together the similar factors of a given
character — one factor from the one germ-cell and the other
from the other. As the zygote forms the individual, so the
paired factors give rise to a character of the individual. The
body characters may be termed the flowers of the factorial
seeds implanted in the germ-cells.
Some characters are simple and derive from one pair of
factors only ; others are of an ascending order of complexity
and may be traced to the cooperative agency of two or more
pairs of factors. In the case of a complex character the
determining factors may be either like or unlike each other.
Thus two pairs of different factors are required to produce the
character of colour in certain flowers ; but it is probable that
certain characters are the outcome of repeated doses of the
same factorial stimulant.
The individual is a dual thing, comparable to a double-
barrelled gun, each barrel loaded with the factorial charge
supplied by one of the two gametes or germ cells by whose
union its duality is constituted. Conversely, a gamete or
germ-cell is of single and not of dual nature ; it has only one
barrel and therefore can give effect to only one of the two
factorial charges with which the individual was supplied at the
time of its formation. The image of the double-barrelled gun
serves to illustrate the several states in which an individual
may exist with respect to its charge of factors of any given
simple body character. Both barrels may be loaded — an
individual in like state has two factorial charges and produces
gametes all of which are alike in the possession of one of these
factors ; such an individual when self-fertilised, or mated with
its like, produces gametes which are all alike in this respect,
and these gametes, fusing in pairs, give rise to individuals
which all possess the character in question; such individuals
are homozygous, they breed true to the character. Neither
barrel may be loaded — an individual in like state is also
homozygous, it breeds true to the absence of the character.
If a gamete of the former individual meet with one from the
latter individual, the resulting zygote is like a double-barrelled
gun with only one chamber loaded ; the zygote is heterozygous
for the character, and unlike the homozygotes, which breed
true, the heterozygous individual does not breed true to the
character in question.
From these propositions it may be predicted that the
offspring of the heterozygote fall into three groups — one
homozygous for the character, another heterozygous, and a
third homozygous for the absence of the factor ; and that
these types of individual occur in the proportion of 1:2:1.
This prediction is verified by experimental breeding from the
heterozygote.
The Chinese Primrose, Primula sinensis, has given rise to
many distinct varieties, white and coloured. It would appear
self-evident that the white races differ from the coloured races
merely in lack of pigment, but Mendelian analysis shows that
there are more subtle differences between the different races.
These differences become apparent when true-breeding white
and coloured plants are crossed with one another ; for it is
then discovered that two types of white-coloured plants exist,
and it is only by their fruits — their offspring — that we may
know them. Thus, if certain white-coloured races are chosen
for the experiment, the result of crossing white and colour is
that all the offspring of the cross bear coloured flowers. If
certain other white races are used and mated with the coloured
form, however, the offspring all bear white flowers. In the
former case, where the first generation (Fi) consists of coloured
offspring, the second generation (F2) raised by self -fertilising
F individuals by crossing with one another, consists of coloured
and white in the proportion of three to one ; hence we conclude
that the white used in this case owes its character of white-
ness to lack of the pigment-producing factor which is present
20
KNOWLEDGE.
January, 1913.
in the coloured parent race. This conclusion is confirmed by
the genetical behaviour of the whites of the F-2 generation ;
such extracted whites breed true to flower-character, and give
rise to white-flowered offspring only. White-flowered races
which behave in this way are termed recessive whites. In the
second case, where the Fi generation consists of white-flowered
offspring, the Fa generation, from selfed or intercrossed Fi
plants, consists of three white to one coloured. The coloured
offspring breeds true ; of the three whites, one breeds true to
whiteness and the other two give rise, like the white Fi genera-
tion, to three white : one coloured. White races which thus
impose their whiteness on the offspring of their union with a
coloured race are known as dominant whites. Mendelians
account for the genetical behaviour of dominant whites by
assuming that they carry the character for colour, and also a
character for colour-inhibition. This hypothesis, though novel
to Biology, is amply justified by genetical results, and it pro-
pounds a series of questions to the physiologist and biochemist.
Until recently, knowledge of the processes of pigmentation
has advanced along two main and independent lines: — (1) that
followed by students of genetics, which has led to a wealth of
exact knowledge concerning the factors and characters which
determine coloration ; (2) that pursued by biochemists, which
has resulted in a great increase of our understanding of the
biochemistry of pigmentation. The first to combine the
genetical with the biochemical method was Miss Wheldale, to
whom we owe a good working theory of the nature of the
processes involved in pigment-formation.
Palladin has shown that respiration consists of a sequence
of enzyme-like actions, the later of which result in oxidation
and are ascribed to the enzymes (ferments) called oxydases ;
that chromogens play a part in the oxidations set up by
oxydases, and that these colourless chromogens may undergo
either alternate oxidation and reduction and so take a contin-
uous part in oxydase action, or undergo permanent oxidation
and so constitute the pigments of the plant. Chodat and Bach
have suggested that oxydases are of dual nature, the complete
oxydase consisting of two parts — a peroxydase and an organic
peroxide. An oxydase reacts with oxidisable reagents, such
as guiacum, to produce a characteristically coloured product ;
hence these reagents may be termed oxydase-reagents.
Peroxydases react with oxydase reagents only if there be
added, as a substitute for the organic peroxide of the complete
oxydase, a source of active oxygen in the form of hydrogen
peroxide. Both oxydases and peroxydases occur in the cells
of plants, and may be identified in extracts therefrom.
Gortner's work on the pigments of insects confirms the view
that pigments are the product of the action of oxydase on
chromogens ; he has shown that the black or brown melanin
of the integuments of insects is produced by the action of an
oxydase called tyrosinase upon some such product of protein-
hydrolysis as ty rosin.
Miss Wheldale's theory is that the anthocyan pigments of
plants are the outcome of a series of chemical changes of the
following order : — Glucosides on being hydrolysed by the
ferment emulsin yield chromogens which, acted upon by oxy-
dases, give rise to anthocyan pigments. The difficulty in the
way of further advance lay in the unsatisfactory nature of the
methods for identifying oxydases derived from plant tissues.
When Professor Keeble and Dr. E. F. Armstrong began their
work on this subject they found, after trials of various known
reagents, that a naphthol and benzidine are each suited
admirably for the purpose of locating oxydases, and by means
of these reagents they have been able to map out the distri-
bution of oxydase and peroxydase in the flowers and other
parts of various plants. Their results confirm Miss Wheldale's
hypothesis of the mode of formation of anthocyan pigments ;
but this confirmation was made possible only by reason of
the fact that they worked with races of plants bred on
Mendelian lines and therefore of known genetic constitutions.
On treating coloured flowers of Primula sinensis with
each of the two reagents, it is found that the actions of
a naphthol and benzidine are in considerable measure supple-
mentary one of the other. Thus, the lilac-blue a naphthol
reaction is confined to the veins of the corolla ; the brown
benzidine reaction is shown by the superficial (epidermal) cells
and also by the veins. The peroxydases are therefore termed
epidermal peroxydase and bundle oxydase, the former occur-
ring in the epidermis and hairs, the latter in the bundle-sheath
which accompanies the veins. Similarly, the stem of P. sinensis
contains a superficial peroxydase and a deep-seated peroxy-
dase. The distribution of peroxydase coincides broadly with
the distribution of pigment ; that is, the peroxydase framework
for pigmentation occurs throughout the species, and the
building of the several colour varieties is determined by the
activity of the factor for chromogen production, and if we
conceive of this factor as administered in a series of doses
we have a picture of the mode of evolution of the series of
varieties characterised by increasing or decreasing amount of
pigmentation of their parts.
The application of these reagents to recessive white races
shows that these white-flowered races, though lacking the
factor for colour, contain in the flower both epidermal and
bundle peroxydase, as might be expected from analogy with
the peroxydases of the stem. Hence we conclude that the
absence of colour from recessive white flowers is due not to
the absence of peroxydase, but to absence of chromogen, and
this conclusion conforms with that arrived at previously by
Mendelian methods, which show that anthocyan pigmentation
of the flower of P. sinensis depends on the presence of one
factor only, and that the absence of pigmentation characteris-
tic of recessive whites is due to the absence of that single
colour-factor.
The investigation of the peroxydases of dominant white
flowers gives a very different result ; for these show no sign of
peroxydase either in epidermis or in bundles. Hence such
flowers either lack peroxydase or else they contain a substance
which inhibits peroxydase from exercising its oxidising action
on the oxydase reagents. It is known that the addition of
certain phenolic compounds (orcin, resorcin, and so on) prevents
tyrosinase from exercising its characteristic action upon
tyrosin. Assuming that an inhibitor of peroxydase exists in
dominant white flowers, it may act either by destroying the
peroxydase or by setting up conditions under which the
activity of peroxydase is arrested ; and if the latter is the
mode of action, it follows that if by some means the inhibitor
can be removed, the peroxydase will be free to effect the
oxidation of the reagents used. This train of reasoning led
Keeble and Armstrong to the discovery that hydrogen cyanide
forms a means of removing peroxydase inhibition ; if dominant
white flowers are immersed in a dilute solution of hydrogen
cyanide and then treated with either of the two oxydase
reagents together with hydrogen peroxide, pronounced peroxy-
dase reactions are obtained both in the epidermal and bundle
tissues of the corolla.
To test this hypothesis further, a race of Primulas was
used in which the flowers are blue with white patches on each
petal, the known ancestry of this race indicating the proba-
bility that the white patches are produced by a localised
inhibitor. On treating corollas of these flowers with the two
oxydase reagents and then with hydrogen peroxide, the parts
originally blue are stained lilac-blue or brown according to
the reagent used, and the inhibitory patches stand out as in
the intact flower as white areas on the coloured ground. If,
however, these parti-coloured flowers are treated first with
hydrogen cyanide, then with the reagent and subsequently
with hydrogen peroxide, the peroxydase reaction is produced
over blue and white areas alike — the inhibition located in the
white areas has been removed. Hence the Mendelian
hypothesis of the inhibitory nature of dominant whites is
confirmed by biochemical methods ; these methods, moreover,
prove that the inhibitor acts not by destroying but by
preventing the action of oxydase upon the chromogen.
This fruitful line of investigation has given various other
results and has raised many questions for further research.
For instance, the close proximity in the flower of the
superficial and deep-seated oxydases suggests that the latter
may cooperate with the former in producing flower-pigments.
This possibility entails the hypothesis of a translocation of
oxydase from the region in which it is secreted to that in
January, 1913.
KNOWLEDGE.
21
which it acts ; and there are various facts in favour of this
view — the lines of deep colour that occur along the veins of
many flowers, the frequency with which the walls of cells
appear to contain oxydase, the occurrence of oxydase in the
mesophyll cells adjoining the bundle sheath, and the evidence
provided by the mutual influence of stock and scion in grafted
plants and in graft-hybrids.
Again, it has been found that the nature and amount of
oxydase contained in a plant tissue varies in an orderly
manner according to external conditions. Among the con-
ditions which determine this fluctuation are light and darkness.
Plants subjected to normal illumination possess less oxydase
than those kept in darkness ; after one or two days of exposure
to darkness, plants of P. sinensis contain more peroxydase
than sister plants kept under normal conditions of
illumination.
Should the results of similar investigations with other plants
show that this diurnal variation of the oxydase content of plant
tissues is general, we may perhaps discover therein the means
whereby many of the phenomena of periodicity shown by
plants are maintained and regulated. The light and darkness
of day and night set up rhythms in the plant ; the leaves of
various plants assume nocturnal and diurnal positions, and the
rhythm thus established may be maintained for a certain time
under uniform conditions of illumination, as in the Sensitive
Plant and many others. Animals also show a similar
periodicity ; the shrimp-like Hippolyte varians rolls up its
brilliant pigment-bodies (chromatophores) at night and becomes
sky-blue in colour ; but when daylight comes the pigment of
the chromatophores is spread out in superficial networks.
Kept in darkness these animals retain for many days this
periodic habit, and when the hour of night arrives, though they
have no light to tell it by, they lay aside their daily garb and
put on the uniform of night. So also the " plant-animal "
Convoluta roscoffensis, which lives on the seashore, orders
its behaviour by the sun and moon, lying on the sand till the
waves of the rising tide are upon it and then descending to
security and darkness ; when the tide recedes it rises to the
light. Even the uncongenial surroundings of a tea-cup and a
laboratory fail to break this habit ; for in these surroundings
its uprisings and down-lyings keep time with the tides. It is
possible that light and darkness may work these wonders of
periodicity and rhythm through the control of chemical agents
such as oxydases.
CHEMISTRY.
By C. Ainsworth Mitchell, P. A. (Oxon.), F.I.C.
THE HARDENING OF FATS.— For many years one of
the chief problems of the oil industry has been to obtain a
harder material from soft fats, and numerous ingenious
methods have been tried, though only with limited success.
The chemical problem involved in the ideal process is the
addition of hydrogen to unsaturated fatty acids or their
glycerides as represented, for example, in the case of oleic
acid by the equation : —
ClH Hfl4 O't "I- H2 = ClH Hjtfi O2
oleic acid stearic acid
Oleic acid is the chief constituent in most oils, while stearic
acid is a main constituent of solid fats such as lard and tallow.
All attempts to make the hydrogen combine with the
unsaturated compounds in this way proved failures until a
few years ago it was discovered by MM. Sabatier and
Senderens that the combination could be effected by bringing
the hydrogen and the liquid fat together at a high temperature
in the presence of finely-divided nickel, which acted as a
catalytic agent.
This discovery was followed by other processes in which
other metals or metallic oxides such as cobalt, palladium and
platinum were used as the catalytic substances, and numerous
patents on these lines have been taken out for the manufac-
ture of solid fats suitable for food and candle-making from
liquid and semi-solid fats.
In the current issue of the Chem. Rev. Fett Ind.. (1912,
XIX, 247) there is a description by Dr. A. Bomer, of the
chemical and physical properties of a number of these
hardened fats prepared from earthnut oil, whale oil and
cotton seed oil. In each case solid products resembling lard
or tallow, according to the duration of the process, were
obtained. From whale oil, for example, a hard white tallow-
like fat melting at 45 • 1° C. was prepared, while earthnut oil
gave a product which closely resembled lard both in its
appearance, chemical properties, taste and smell.
As these hardened fats are now being sold as food products
physiological tests were made to discover whether any
injurious substances were formed in the process, but they
were found to be quite innocuous, provided that care had
been taken to eliminate all traces of the nickel used in the
manufacturing process. Stress is laid upon the point, how-
ever, that only liquid fats that are already fit for human food
should be used as the raw material, while such fats as
horse-fat, bone fat, whale oil and the like should be kept for
technical purposes such as the making of soaps and candles.
METROPOLITAN WATER BOARD'S REPORT.— The
sixth annual report of the results of the chemical and
bacteriological examination of the London waters, which has
just been published, contains many details of great interest,
to which here it is only possible to allude briefly. The raw
waters, from which the supply is drawn, consist principally of
rivers that have previously been polluted with sewage, and in
the future it will be an increasingly difficult matter to obtain
sufficiently satisfactory water to meet the greater demands
upon the waterworks. Obviously, the greater the quantity of
the water drawn from a river the more impure will be that
which remains. Chemical purification of sewage effluents
has rendered them much less objectionable ; but apart from
sterilisation there is no practical method of removing bacteria
from these effluents.
Fortunately, the effect of mere storage of the water is
automatically to reduce the number of bacteria to the extent
of over ninety-nine per cent., so that on subsequent filtration
of the water a reasonably safe filtrate is obtained. For
example, the average number of microbes in raw Thames
water during the twelve months ending March, 1912, was
9155 per cubic centimetre, while after subsidence and filtration
of the water there were only 17-2 per cubic centimetre.
•In Dr. Houston's opinion it is hardly conceivable that
any pathogenic micro-organism would succeed in reaching
the filter beds after a sufficient period of storage. At the same
time he lays stress upon the importance of obtaining water
in as pure a condition as is practically possible, notwithstand-
ing the proved safeguard afforded by efficient storage.
Theoretically it should be possible to bring all river water to
the same degree of purity before its intake into the water-
works and its delivery to the filter beds; but in practice during
periods of flood it is necessary either to draw upon such water,
which is unsuitable for the purpose, or to deplete the reservoirs
by closing the intakes and thus reduce the period of storage
for water subsequently taken into store.
For these reasons Dr. Houston advocates the desirability
of taking greater supplies of water at favourable periods than
is at present permitted. Apart from this, it is suggested that
supplementary processes of purification might with advantage
be employed occasionally, in addition to the present processes
of devitalisation of bacteria by sedimentation and removal of
the bulk of the remainder by filtration.
CHEMISTRY AT THE BRITISH ASSOCIATION.—
The address of Professor Senier, President of the Chemical
Section at the Meeting of the British Association in Dundee,
is an interesting outline, full of suggestion, of what chemistry
is and by what methods it works. It is clearly demonstrated
that imagination is necessary for the advance of the science,
and that our educational resources should be devoted to
assisting promising students in the direction of research rather
than to giving an elementary smattering of indigestible facts
to everyone.
Of the papers of more general, apart from purely chemical
interest, mention may be made of The Report of the Com-
mittee on the Study of Plant Enzymes particularly with
22
KNOWLEDGE.
January. 1013.
Relation to Oxidation ; and the very important Report on
Diffusion in Solids by Dr. C. H. Desch, in which the con-
clusion is drawn that " the occurrence of diffusion in metals
is established beyond any doubt ; but that experiments are
still lacking to prove its occurrence in transparent crystals of
minerals, salts, or organic substances, even under favourable
conditions, although, even here, indirect evidence points to its
possibility."
Other notable papers are On the Dissociation of Phos-
phorus Vapour, by Professor Stock and Dr. Gibson, and
The Chemical Nature of Uranium X, Radio-Actinium
and Thorium B by Mr. Fleck, who was unable by means of
fractional precipitation to effect any concentration of the
short-lived radio-element in thorium, or to separate thorium
from radio-actinium or thorium B from lead.
GEOLOGY.
By G. W. Tyrrell, A.K.C.Sc, F.G.S.
GEOLOGY OF THE LIZARD AND MENEAGE — A
memoir with the above title has just been published by the
Geological Survey, and written by Dr. J. S. Flett and Mr. J. B.
Hill. The Lizard has long been a happy hunting ground
for geologists, largely on account of its fascinating petrological
problems, especially those connected with the great mass of
serpentine which is the central feature of its geology.
The Lizard area can be divided into a northern and a
southern portion. The dominant feature of the northern
portion is the occurrence of four bands of sedimentary rocks
(killas or clay slate, with subordinate grits, limestones, and
conglomerates), named the Mylor, Falmouth, Portscatho, and
Veryan series respectively, of which the last-named is the
youngest, and has been determined by fossil evidence to be
approximately of Llandeilo or Arenig age. Volcanic activity
in Veryan times gave rise to the well-known spilitic lavas
of Mullion Island, which are interbedded with limestones and
radiolarian cherts.
The southern area is composed of a great metamorphic
series, consisting of sedimentary and igneous rocks, of which
the latter are overwhelmingly predominant. The metamor-
phosed sedimentary rocks are the oldest, and consist of
mica-schists, granulites, and green schists, containing also
hornblende schists of undoubted igneous origin. Subsequent
to the formation of these rocks, an intrusion of granite took
place. This rock has been greatly metamorphosed, and is now
a highly foliated hornblende gneiss, which occupies the Man
of War Islands off the Lizard shore.
Before the intrusion of the great serpentine another sedi-
mentary formation was deposited, the Treleague quartzite, a
quartzose rock in which the original pebbly structure is well
preserved. In many places also, on the margin of the
serpentine, there are coarse, gnarled, hornblende schists —
the Traboe schists — representing the coarse dolerites or
gabbros which immediately preceded the great plutonic
intrusions.
The serpentine covers an area of twenty-one square miles,
and is probably the largest serpentine mass in the British
Islands. It has a more or less circular outline and is clearly
a large laccolite or boss similar to the granite bosses that
stud Cornwall and Devon. Three main varieties have been
distinguished, the cherzolite or bastite-serpentine, the
tremolite-serpentine, and the dunite serpentine. The first
named of these is the rock which affords the beautiful
ornamental stone for which the Lizard serpentine area is
famous.
Later the serpentine was invaded by some bosses and an
enormous number of dykes of gabbro. In many localities
these have been crushed and rolled out with the formation of
" flaser" -gabbros. After the cooling of the gabbro, a further
injection of basic material took place, giving rise to abundant
black dykes of olivine-dolerite, many of which have been
crushed into epidiorites and hornblende-schists. Before this
episode had finished, a final uprush, this time of acid material,
occurred ; and in some places, a mixed or hybrid rock, con-
sisting of imperfectly mingled acid and basic material was
produced, forming a heterogeneous banded gneiss called the
Kennack Gneiss.
It is interesting to remark how this long and intricate
igneous period of the Lizard is paralleled in the Ordovician of
Ayrshire. Here also is a large mass of serpentine, intruded
by gabbro and dolerite dykes with later masses of acid
material. These intrude Ordovician sediments, the basal
portions of which contain numerous flows of spilitic lavas
associated with limestone and radiolarian cherts just as in the
Mullion Island district of Cornwall.
THE PETROLOGY OF SANDSTONES.— The petro-
logical study of the sedimentary rocks is now an important
adjunct to their stratigraphical study. The investigation of
the constituent grains of a sandstone is often especially
helpful in obtaining an idea of the mode of origin and the
derivation of the rock. Important results are being obtained
from the study of the Scottish Carboniferous sandstones. An
investigation by Mr. T. O. Bosworth, brought forward at the
British Association, shows that these sandstones belong to
two entirely different kinds, those in which the heavier
mineral grains consist mainly or largely of garnet, and those
in which garnet is absent or scarce. As far as Mr. Bosworth
has yet examined the Carboniferous succession, the Coal
Measure sandstones have been found to be highly garneti-
ferous, whilst those of the underlying Millstone grit were
almost entirely non-garnetiferous. In the sandstones of the
Carboniferous Limestone Series, out of fifteen samples
examined, nine were garnetiferous, and six devoid of garnet.
The Calciferous Sandstones were found to be entirely non-
garnetiferous.
The garnets, and indeed all the heavy grains, were found
by Mr. Bosworth to be characteristically angular. The
garnets were broken along the dodecahedral cleavages, giving
elaborate zig-zag shapes with numerous corners and edges.
These grains were in marked contrast to those found in desert
sands.
An independent investigation by Mr. W. R. Smellie (Tran-
sactions of the Glasgow Geological Society, 1912) of the
Upper Red Barren Measure sandstones, which overlie the
Coal Measures to the east of Glasgow, shows that the sand-
stones suffer a progressive change upwards in regard to
mineral content and the degree of rounding. The lower beds
are still characterised by angular garnets, but these do not
occur to nearly the same extent as in the Coal Measure sand-
stones. The higher beds, however, are devoid of garnet, and
contain abundant zircon, rutile, and tourmaline, the grains of
which are frequently well-rounded and polished, especially
the zircons.
MICROSCOPY.
By F.R.M.S.
LOW POWER PHOTO-MICROGRAPHY.— BACK-
GROUNDS.— It is a practical maxim in picture making of
all kinds, scientific, technical, and pictorial, that nothing is
seen without a background.
Thus a uniformly lighted quite white object is unnoticeable
against a uniformly lighted equally white background.
The next point is that the useful effect of a background is
to show contrast. This is so obvious that that it is very
frequently entirely ignored. In Figure 20 we have a pre-
cisely similar pair of tiny cowrie shells side by side, similarly
lighted. That on the right is backed by black paper, that on
the left by a bit of white postcard ; the two backgrounds
being pasted side by side on an ordinary micro slip so that
both parts had the same lighting, exposure and development.
First we notice that the shell on the right seems to be
decidedly lighter than that on the left. But this is an optical
delusion due to contrast effects with the backgrounds. Next
we notice that with the light background (left) we get a
decided cast shadow as well as a shaded side, and that where
this side of the shell is close to the light card background
we get a little reflected light on the shadow side, while with the
January, 1913.
KNOWLEDGE.
23
black background (right) the cast shadow is apparently absent
though really present.
It may be here noted that general experience among photo-
graphers shows that with a dark background we require a
little longer exposure than with
a light background, all other things
remaining the same. With certain
types of subjects it is desirable to
employ a light background in
conjunction with a side lighting,
but without any cast shadow such
as shown in my last note.
This can be easily accomplished
in those cases where the object
can be affixed to an ordinary
clean, clear glass micro-slip. This
is now held by the spring clips in
front of the cut out part of the
holder, and then a suitable white
ground (e.g., postcard) put in a
position and angle where it is
well and evenly lighted, and a
few inches away from the object.
iJtfJS 22 ,we,see this arrangement showing a postcard
background and glass-supported tiny shell and in Figure 21
we have the result showing the object enlarged
about four diameters with a side lighting,
light ground and no cast shadows.
In Figure 23 we have a (practically) white
shell supported on a glass slip in a side lighting
against a black ground. In this case the
ground was a bit of black velvet pasted to a
piece of cardboard. It is far enough away to
be quite out of focus and shows no texture.
Next conies the question of a reflector, which
in some cases is of special value. In Figure 24
we see an object stuck to a glass slip, and a
bit of white card close behind it. To our
right we see a postcard used as a diffusing
and reflecting screen throwing light on to the
shadow side of the object. (The postcard is
affixed to the base board with a couple of
drawing pins.)
In Figures 25 and 26 we see the effect of the
non-use and use of such a card reflector in the
case of a light shell showing some curious black markings
In the one case we get a dark shaded side and a cast shadow
on the background. In the other
case we nearly get rid of the cast •
shadow and also see a great deal
more detail on the shadow side
of the object as well as seeing
more of the inside of the shell
mouth.
These two examples, Figures
25 and 26, are precisely similar
as regards lighting, exposure,
and so on, and in all other
respects, except the matter of the
reflector.
One word of warning : do not
use a glass mirror, or even a
glossy card, or cross lighting and
other ugly effects are likely to
arise.
For all work of this kind it
is preferable to employ bright
sky light rather than direct sun-
light. If direct sunlight falls on
the window this should be cov-
ered with a piece of thin fine white muslin.
F. C. Lambert, M.A., F.R P S
1QRUEx,ETp MICROSCOPICAL CLUB.-November 26th,
\ r Resident, Professor A. Dendy, D.Sc, FRS in
the chair. '
The President made some remarks on new species of
IGURE 20.
Figure 22
Holothunans, with special reference to a form of Chiridota
found in Port Phillip Bay, Victoria, and described by E C
Joshua as Taenwgyrus allani. It was not, as was at first
thought, identical with Chiridota dunedinensis Parker.
Mr. E. M.^Nelson, F.R.M.S., read
a paper "On microscope con-
struction and the side-screw fine-
adjustment." He pointed out
that the modern method of placing
the coarse-adjustment slide and
the body upon the fine-adjust-
ment, and the side-pinion fine-
adjustment (now so much in
vogue), were both invented by
Powell, in 1841. The disadvan-
tages of modern horizontal fine-
adjustments were mentioned, and
an improvement suggested by the
author, preventing injury to the
delicate moving parts, was des-
cribed. The same author also
made some remarks on " a new
low-power condenser," and re-
ferred to the impossibility of obtaining an evenly lighted
held, under critical illumination with any power lower than a
^^^^^ two-thirds. Substage condensers suitable for
low powers are all of too short a focus. A
sufficiently long-focus condenser cannot be used
because there is not room to focus it, even on
a Powell and Leland No. 1 stand. The author
had surmounted the difficulty by designing a
condenser on the telephoto principle. This
was exhibited at the meeting by Mr. Baker.
It had an equivalent focal length of four
inches, but required only one inch of working
distance.
ROYAL MICROSCOPICAL SOCIETY —
November 20th, 1912. H. G. Plimmer, Esq.,
t.R.S., President, in the chair. Messrs. E.
Heron-Allen and A. Earland read a paper on
the Distribution of Saccammina sphaerica
M. Sars and Psammosphoera fusca Schulze
in the North Sea; particularly with reference to
the suggested identity of the two species
a * u- -j These Foraminifera, belonging to the familv
Astrorhizidae, and originally described as from the North Sea
but occurring also in all the great oceans, have been the
subject of considerable contro-
versy. Dr. Ludwig Rhumbler
asserts that Psammosphoera is
only an immature stage of
Saccammina. As a result of
the examination of about one
hundred and fifty dredgings
made in the North Sea, the
authors have no hesitation in
affirming that the life-history of
Saccammina, as recorded by
Rhumbler, is a composite sketch
involving three separate and
generally recognised specific
organisms : —
Stages I— III represent the life
history of Crithionina mamilla
A. Goes.
Stage IV is Psammosphoera
fusca Schulze, an extremely
variable species, which occurs
both free and sessile, but is in
, , , all its stages normally recognis-
able by the absence of a general aperture.
Stages V-VII represent the complete life-cycle of Saccavi-
mma sphaerica Sars, so far as it is a shell-bearing organism
An abstract of a paper by the Rev. Hildenc Friend on
British Henleas was read. The Henleas are microscopic
annelids belonging to the family of Euchytraeids. The genus
Figure 21.
■■■■■
24
KNOWLEDGE.
January, 1913.
was created in 1889 by Michaelsen, and contained four
authentic species and four which were doubtful. Another
species was added in 1899 by Bretscher. In 1900, when
" Das Tierreich " was published, the number recorded was
five, with four doubtful forms.
During the next decade some
progress was made, eight new
species being added, and four
definitely recorded as British. In
1911 Friend described H. perpu-
silla, and added one or two others
to the British list. The present
paper gives an enumeration of no
fewer than nineteen species,
eighteen of which are found in
England and one in Ireland.
Of these, seven new to science
were found at Hastings in Decem-
ber last, and three have been
found in Nottingham during the
present year. Descriptions, with
figures, are given of H. marina,
H. curiosa, H. arenicola, H.
heterotropa, H. attenuata, H. fridericoides, H. variata,
H. triloba and H. fragilis, all new to science. The paper
closes with a carefully prepared
table, by means of which the
various species can most readily
be distinguished.
An abstract of a paper by Mr.
James Murray, F.R.S.E., on African
Tardigrada was read. This paper
adds thirteen species to the list of
African Tardigrada, twelve were
described in the author's previous
paper, and Daday added a new
species, M. tetronyx. There are
now twenty-six species recorded
for Africa, eighteen for tropical
Africa, and seventeen for South
Africa. Nine of these were first
discovered in Africa, and only one
of them (E. perarmatus) has been
found outside that continent. Our
knowledge is still too incomplete
to allow of any useful study of
the origin and distribution of
the African Tardipode fauna.
Amended and fuller descriptions
are given of E. africanus and
M. crassidius. Only one new
species is described, M. allani,
but there are figured varieties of
E. crassispinosus, E. duboisi, and
hupelatidioides which are prob-
ably of specific value, to which I
j?ive no names. In the present state of the group it is well to
be cautious in making new species, till our knowledge is
Consolidated in some
monographic work. ^^m^^^bb^^^^^^^^h^^^m
INSECT INTEL-
LIGENCE. — At a
meeting of the Royal
Microscopical Society
on December 18th
Mr. Frederick Enock,
under this title, des-
cribed how a wood- H
boring wasp brought
no less than twenty-
seven examples of
the rarest British
"Daddy-longlegs" (imperialis — of which Mr. Enock had only
taken one in forty years) and in order to get them into its
burrow, cut off the six legs and the two wings close to the body.
Figure 23
Figure 24.
Figure 25.
ORNITHOLOGY.
By Wilfred Mark Webb, F.L.S.
THE CUCKOO. — As an instance of the interesting infor-
mation which one can sometimes
glean from a catalogue one may
mention that of Major Proctor's
collection of birds' eggs recently
sold by Mr. Stevens. That the
cuckoo chooses a nest of the same
species of bird in which to deposit
its eggs is shown by two eggs evi-
dently laid by the same individual,
one taken from a Reed Warbler's
nest on May 31st, 1907, and the
other from that of the same species
in the same place (Twy ford, Berks)
six days later. That the Cuckoo
deposits two eggs in the same nest
was shown by that of a Hedge
Sparrow found at Dean, in Hamp-
shire, on May 31st, 1893. Another
Cuckoo's egg in the collection was
found by Major Proctor in a Blackbird's nest at Torquay
in 1889.
THE RECOVERY OF
MARKED BIRDS.— In British
Birds for December a report on
marked birds that have been re-
covered, is given. In many cases
the specimens were recaptured in
the same place. One or two of the
instances of birds that havetravelled
a considerable distance we may
give. A Linnet marked by Mr.
Masefield at Cheadle, Staffordshire,
as a nestling, was caught at
Wellington, Salop, on September
25th in the same year. A Pied
Wagtail, marked by Mr. Ford-
Lindsay at Pett, Sussex, on June
20th, 1912, was recovered at
Blaye, Gironde, France, on Octo-
ber 6th. A Whinchat and some
Cormorants, Common Terns and
Little Terns also went to France.
A Lapwing, marked by Lord Lucas
in Yorkshire on June 19th, 1912,
was recovered in Portugal in
November of the same year.
THE DARTFORD WARBLER
IN IRELAND. — Mr. R. If.
Barrington.in The Irish Naturalist
for December, records the occur-
rence of the Dartford Warbler in
Ireland, a female having been caught at the Tuskar Lighthouse,
Countv Wexford, by Mr. A. O'Leary, the light-keeper, on
October 27th. The
Dartford Warbler is
looked upon as a
resident in England,
and was said in 1880
not to be uncommon
on furzy ground in
the Land's End dis-
trict. Mr. Barrington
thinks that if a pair
had arrived in County
Wexford, where furze
is more prevalent
than any Irish, or
probably English,
county, a colony might have been established ; that is to say,
were the birds lucky enough to escape being killed by a
collector or some other misguided person.
Figure 26.
January, 1913.
KNOWLEDGE.
25
NESTING - BOXES IN RUSSIA.— In many parts of
Russia, especially in the towns along the Baltic, the traveller
cannot help being struck by the numbers of nesting-boxes
in the gardens and courtyards. This is
particularly noticeable in the quaint old town
of Libau, where in almost every garden,
however small, a nesting-box may be seen.
These boxes are invariably stuck on the top
of a pole — never against the trunk of a tree or
the side of a house as with us in England.
In many cases a small branch is fixed to the
box to render the site more natural and attractive.
This pleasing custom is due to a pious desire
to shelter the Dove, a bird entirely sacred to
the Virgin in Russia, and which is never molested
in any way, much less killed and used for food
— indeed, anyone found guilty of such an act
would run the risk of serious reprisals from the
neighbours.
The name Dove embraces any kind of pigeon,
wild or tame, and fancy kinds are often kept as
in England.
The owners of those boxes which happen to
attract a Dove are greatly envied, as the privilege
of harbouring and sheltering the " Virgin's Bird "
is considered to entail good luck. Of course,
only a small proportion of these boxes are
selected by Doves ; Starlings and other birds
make frequent use of them, and are always
welcome.
Figure 27 is from a sketch which I made of a
typical box in the garden of a small house in
Libau. Notice the two small perches below the
entrance hole. Lionel E. Adams.
PHOTOGRAPHY.
By Edgar Senior.
PHOTOGRAPHING ROCK SECTIONS.— One of the
most interesting, and at the same time valuable, applications
of photography to the microscope,
especially when considered from an
educational standpoint, is its use
in obtaining permanent records of
geological specimens. In work of this
nature, except in very few cases,
low powers are all that are necessary.
Although quartz, felspar, and mica
form the chief constituents in rocks,
the other substances which occur
being of secondary importance, the
sections themselves vary so much
in character that the method of
illumination employed in one case,
may be totally unsuitable in another,
so that no absolute rule can be laid
down, the operator having to use his
own discretion in the matter. With
a little experience, however, there
will be no difficulty in judging the
most suitable means to employ in
order to obtain the desired results.
With a large number of rock
sections it is necessary to make use
of polarised light in order to differ-
entiate their structure, and in some
cases selenite and mica films, used
either separately or in combination
are an advantage also. In many
cases the best results photo-
graphically are got by means of
the crossed nicols only ; many forms
of granite are of this nature, as they give so much colour
themselves that only crossed nicols are required. Others
again require the selenite to show them properly. In
the accompanying illustration Figure 28, which is from a
Figure 27.
Typical Russian
Nesting-box.
Figure 28.
Section of Aberdeen Granite photographed
with polarized light X 70 diameters ; objec-
tive employed 24 mm., together with a two
projection ocular.
section of Aberdeen granite, a red and green selenite
plate was used, in order to show the structure at its
best for the purpose of photography. In taking the
negative, a twenty-four millimetre objective was
used, with the analyser screwed into the
nosepiece above it, and a two-projection ocular
as eyepiece. An achromatic sub-stage con-
denser with its top lens removed, and the
polariser fitted in below completed the whole
optical arrangement, the source of illumination
being a paraffin oil lamp. In order to make a
correction for the so-called chemical focus of
the objective, the light was filtered through
an orange glass screen. It may not perhaps
be apparent why this is necessary, considering
the conditions under which the photographs are
taken, but it has been found better in practice
to do so, especially if lantern slides are going
to be made from the negatives. One very
essential condition above all others in order
to ensure success in work of this class, is
that the sections must be thin, otherwise
the definition will be very seriously impaired.
There should not be much difficulty in this,
however, with the improved methods in use
now for making sections. In taking the
photographs it is advisable to bear in mind
the photographic values of the colours, remem-
bering that they have to be translated into
monochrome, and that however fine the effect
may be when seen in colours, the result may
be totally disappointing in black and white.
It therefore becomes necessary to employ plates
which by falsifying the luminosities of the
colours themselves produce the necessary con-
trast in the finished photograph. This very power becomes
at times of immense value, as in objects which exhibit colours
under polarized light such as plant-hairs, cotton-fibres, silk,
flax, hemp, and so on, it affords a means of rendering details in
structure which would otherwise be lost. In preparing slides
for use, the objects should when-
ever possible be mounted in balsam,
as the effect is much more striking
than when mounted dry or in water.
Then, again, the Lumiere Auto-
chrome process affords a means of
producing very fine lantern slides
showing the colours themselves, and
when photographing in this way
the compensating screen for sub-
duing the too great action of the
blue, is not required when the oil
lamp is used, as the colour of the
light is sufficient in itself for the
purpose. It will also be found that
with moderate powers the exposure
is not long.
PHYSICS.
By Alfred C. G. Egerton, B.Sc.
DENSITY OF LIQUIDS.—
While investigating the behaviour
of various liquids of different
densities which were sufficiently
insoluble to maintain a meniscus of
separation, Professor A. L. Clark
finds that chloroform and water
have equal density at a certain
temperature. The two liquids are
placed in a thick-walled capillary tube which is placed in a
paraffin bath. The chloroform is denser than water at the
ordinary temperature, but at a few degrees below the critical
temperature (260°) the chloroform rises to the top ; as the
26
KNOWLEDGE.
January, 1913.
system cools down, so the chloroform again sinks to the
bottom. This experiment is similar to those devised by Mr.
C. R. Darling : as, for example, with aniline and water.
The solubility of the liquids in each other causes the
equilibrium to become unstable and the position of the
liquids to reverse, at a temperature slightly different from
the temperature corresponding to equal density. Chloroform
and water have different indices of refraction, but as the
temperature rises the index of chloroform decreases more
rapidly than that of water, and when the two indices become
equal the separating surface disappears from view and gives
the appearance of complete homogeneity.
THE PHOTOELECTRIC EFFECT.— When metal
surfaces are exposed to ultra-violet radiations, negative
electrons are expelled from these surfaces. •■ Each metal has
a definite photoelectric effect of its own. It is interesting to
gain knowledge of the emission velocities of the electrons from
the salts of metals and various compounds, and the work of
Dr. A. LI. Hughes supplies that information. It was necess-
ary to experiment with surfaces of which the state of the
surface is similar to the mass of the substance, because the
photoelectrons come from a layer only a few molecules in
thickness. This has been ingeniously effected by vaporising
the substance in vacuo from a small quartz bulb furnace,
electrically heated, on to a nickel disc lowered near the mouth
of the furnace. Most halogen salts show marked photoelectric
effect after exposure to light, but such substances as zinc
chloride or phosphorus pentoxide show no such effect. It
appears that only those substances which are decomposed by
light show the photoelectric effect, and that the light first
decomposes the surface and then acts on the metallic element
in the ordinary way.
SILENT DISCHARGES.— In Chili, observations have
been made on the " Andes glow," which appears to start from
an altitude of ten thousand feet along a ridge or conical peak.
Luminous arcs up to 25° in width, surrounding a dark core,
or radial groups of rays shooting up as far as the zenith, were
observed, and lasted for several seconds. The phenomenon is
frequent on warm, clear nights.
FLICKER. — When a disc with black and white sectors is
spun round at a moderate speed, a flicker may be seen ; on
increasing the speed the flicker disappears, but if the illumina-
tion increases the flicker may reappear if the speed is not too
great. The disappearance of the flicker is connected with the
speed, the intensity and hue of the illuminating light, and with
certain physiological effects on the eye. Dr. T. C. Porter has
investigated the connection between illumination and critical
speed at which flicker vanishes, and an abrupt alteration in the
relation occurs when a certain low illumination is reached,
and this must in some way be connected with the behaviour
of the eye. Mr. H. E. Ives has published a detailed investiga-
tion on the application of the " flicker " method to the photo-
metric comparison of lights of different hue, a problem of
considerable complexity. The relative brightness of differently
coloured lights is not constant under all conditions, owing to
two main physiological effects — the Purkinje effect and the
" yellow spot " effect. The former is the greater sensitiveness
of the eye to blue light at low illumination, and the latter is
the change of relative brightness of different colours when the
size of the field of view is changed and different areas of the
retina of the eye are illuminated. Mr. Ives has found the
reverse of these effects when experimenting with the flicker
method of comparing lights of different colours. There are
four methods open to the comparison of lights of different
hue, viz. : —
(I) The estimation of the sensation of equal brightness.
(II) The visual acuity or the estimation of the fineness
of detail detectable as the luminosity decreases.
(III) The critical frequency or the comparison of the
intensity of the light illuminating discs of black and the
colour at the same speed of alternation.
(IV) The " Flicker " method, when the two colours
alternate and the slightest change of either at a particular
speed produces " flicker."
The work of Mr. Ives will certainly lead to a method of
comparing the intensity of light of different hue, but the
accuracy will always be dependent on the eye of the observer
to some extent.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A.
HOW DOES EXPERIENCE COUNT FOR THE RACE?
It is certain that many animals have an inborn capacity of
reacting in a definite and adaptive way to particular stimuli.
We call their behaviour instinctive. In many cases it seems
possible to think quite clearly about the possible origin of
these inborn capacities. We can think of them beginning as
germinal variations; we can think of them progressing as
germinal variations ; we can think of them being most subtly
perfected in the course of Natural Selection. And all without
supposing that the tutelage of experience counted for anything
except in the individual lifetime. This is the ordinary
Darwinian view, in contrast, for instance, to the view of
Professor Richard Semon, who holds very strongly that we
must suppose that the offspring directly benefit by the
premiums which their parents and ancestors have paid to
experience. And some of the cases of very specific instinctive
reaction are so striking that one is inclined, at first sight at
least, to conclude that the lessons of experience must be in
some way entailed. Let us cite one case taken by Semon
from Lenz's " Schlangen und Schlangenfeinde " (Gotha, 1870).
Lenztook two young buzzards from the nest and reared them.
They killed slow-worms and ringed snakes carelessly, but they
were in a most striking way excited when they first had to
deal with an adder. They had previously devoured pieces of
adder's flesh quite greedily, so it could not be smell that
pulled the trigger. Moreover, buzzards work by sight. Now,
what was it made the buzzards treat the adder in a way
entirely different from that in which they dealt with grass
snakes ?
VINDICATION OF THE CABBAGE FLEA.— When we
turn up the well-known leaflets of the Board of Agriculture
under the heading Cabbage Flea or Haltica oleracea, we
find it stated that this little bluish-green beetle is often far
more harmful than the Turnip Flea, that " in some districts it
is the chief root crop and general pest," and that it " attacks
old and young plants, especially cabbages, but also turnip and
other crops." Now we do not wish to take up the cudgels on
behalf of flea-beetles, but it is of interest to call attention to a
vigorous protest by Franz Heikertinger in Vienna, who has
been engaged for seven years in a study of the Palaearctic
Halticinae. The cabbage flea has been grossly libelled. It
frequents Polygonaceae like buckwheat and Onagraceae like
willow herb. It does not frequent Crucifers, nor eat them,
nor develop on them. The fact seems to be that Haltica
oleracea has been carelessly mixed up with species of
Phyllotreta such as Ph. nemorum, the turnip-flea-beetle,
and with species of Psylliodes, such as Ps. chrysocephala.
It is strange that the mistake should have remained so
long undetected, and it is satisfactory to have it corrected.
For not only should justice be done even to a flea-beetle, but
it is of practical importance in agriculture, that the true culprit
should be persecuted.
CTENOPHORES. — In his finely-illustrated memoir on the
Ctenophores of the Atlantic coasts of North America, Mr.
A. G. Mayer calls attention to the fascinating beauty of these
animals. " In the extreme tenuity of their bodily substance
and their diaphanous delicacy of coloration, the ctenophores
stand apart from other marine animals. Their presence in
the water is commonly denoted only by the brilliant flash of
rainbow colours, which play along the lines of their ciliary
combs as they move languidly beneath the unrippled surface
of the sea. Yet these creatures are no more wonderful in
their complex organization than in their remarkable adjustment
to their habitat; for so delicate are most of them that a
current such as that of an oar suffices to tear them into mis-
shapen shreds — a fate which they escape in time of storm by
January, 1913.
KNOWLEDGE.
27
sinking far into the depths. This fact accounts for the
extreme rarity of many of these forms, for the ocean's surface
must have remained flat as a mirror for many hours before
they can be lured upward from the calm of their deep retreat.
Yet tender as they are to the touch, passing jelly-like between
the fingers of the hand that attempts to seize them, their food
consists largely of young fishes which they engulf in great
numbers, seizing their prey by means of their peculiar adhesive
cells. Thus, in the cold northern waters where ctenophores
occur in vast swarms, they constitute a serious menace to the
cod fisheries by devouring pelagic eggs and young fish."
FIVE-YEAR PEDIGREED RACE OF PARAMOECIUM.
— Many facts seem to point to the conclusion that conjugation
or fertilisation in Protozoa renews the vigour of the cell-lineage.
Another view is that fertilisation is in some way concerned
with the phenomenon of variation, or that it may enable
the units to withstand changed environmental conditions.
Professor Lorande Loss Woodruff has devoted many years
to the experimental study of the slipper animalcule (Para
moecium), and one of his last papers is very interesting.
On May 1st, 1907, he started with a " wild " Paramoecium
aurelia, isolated from an aquarium. When it had produced
four individuals by division, these were isolated to four lines.
The pedigreed culture has been maintained by a specimen
isolated from each of these lines practically every day up to
May 1st, 1912, thus precluding the possibility of conjugation
taking place and facilitating an accurate record of the number
of generations attained.
In the five years there were three thousand and twenty-nine
generations, four hundred and fifty two in the first, six
hundred and ninety in the second, six hundred and thirteen
in the third, six hundred and twelve in the fourth, and six
hundred and sixty-two in the fifth. The mean rate of division
was over three divisions in forty-eight hours. The organisms
were as healthy in 1912 as in 1907. They had given evidence
of the potentiality of producing a volume of protoplasm
approximately equal to lo1000 times the volume of the
earth ! This seems to show that in favourable environment
there is no need of conjugation and no reason for senescence.
FILOPLUMES. — It is usual to distinguish on a bird four
kinds of feathers, — the ordinary contours, the down -feathers,
the half-down, and the filoplumes. The last are most familar
on a plucked bird, standing up in scores on the bare body,
each like a hair with a tuft at the top. Very little is known
in regard to their development or their replacement, but Otto
Fehringer has recently described their arrangement in a
number of representative birds. They occur regularly along
with contour-feathers and occasionally with down feathers.
Their pits or follicles are separate from those of their com-
panion feathers, but closely juxtaposed. If contour-feathers
grow strong at one part of a feather-tract, so do the filoplumes.
On the main feather-tracts, the filoplumes occur in definite
relations to the contour-feathers. Thus, if the contour-
feather is median and directed backwards, it has a filoplume
on each side of its base ; if the contour-feather is lateral and
directed outwards and backwards, the filoplumes are on the
median side ; if the contour-feather is lateral, but directed
inwards and backwards, the filoplumes are on the lateral side.
SOLAR DISTURBANCES DURING NOVEMBER, 1912.
By FRANK C. DENNETT.
November has proved very unfavourable to the solar observer.
Six days were too cloudy to admit of observation, and some
others were too dull to yieid very satisfactory results. The
disc was apparently clear of disturbances, bright or dark, on
thirteen days, and on eight only faculae were visible. At noon
on November the 1st, the longitude of the central meridian
was 90° 3'.
No. 23. — The only spot disturbance seen was first recorded
on the 17th, the Sun not having been visible on the two
previous days. At 10.45 a.m. it was described as a small
very black spot having little penumbra, but followed by an
elliptical faculic disturbance containing at least eight pores.
A little after noon the edge of the umbra was observed to be
frayed, and at the other side of the faculae were indications of
a trailer or end spot. Directly eastward of the leader a dark
hydrogen floculus was visible with the spectroscope, pointing
towards the S.S.E., deflecting the C.-line towards red. On the
18th the group seemed little altered and when last seen, on
the 19th, there appeared to be two spots, one at each end,
but clouds intervened before measures could be completed.
On November the 30th there was apparently a badly-formed
spot in the equatorial region near longitude 95°, with traces of
•pores in a rough-looking area by which it was surrounded.
No measures were obtained. It was doubtless the remains of
the disturbance which produced the groups of Nos. 18 and 20.
Faculic disturbances near longitude 10°, S. latitude 6° to
10°, were observed within the eastern limb, on November 1, 2,
3, and 29, and approaching the western edge on the 11th.
The faculic area connected with the spot group 23, was seen
as it approached the western limb on the 25th and 26th.
In the preparation of this little note the importance of com-
bined study by observers at distant stations cannot be over-
estimated. Six observers at five stations so far separated as
Lisburn, Manchester, Bath, Margate and Hackney, the
greatest number of observations at any one station being
eighteen. The observers were Messrs. J. McHarg, A. A.
Buss, C. Frooms, E. E. Peacock, W. H. Izzard, and the
writer.
DAY OF NOVEMBER, 1912.
7
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THE FACE OF THE SKY FOR FEBRUARY.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Feb. 5
Greenwich
Noon.
Sun.
R.A. Dec.
h. m.
21 14*3
21 34'3
21 53*9
S.i6*o
14*4
12*8
Moon.
R.A. Dec
20 47 '4 S. 22*3
o 26*8 N. 3*3
4 3T"0 N.26*7
9 456 N.i7*i
14 14*2 S. i6'6
Mercury.
R.A. Dec.
20 54*3 S. 19*6
21 296 17'°
22 4*4 T3'9
22 39*2 10*1
23 13*2 S. 6*o
Venus.
R.A. Dec.
o 27 I
0 44*9
1 2'0
i i8*3
N. 1*6
4*2
6*6
9*0
N.i 1 '3
Jupiter.
R.A. Dec.
h.
18 31
18 36*1
18 40*4
" 44 '4
"'3
*8 S.-
48*3 S."
23 'o
22*9
Saturn.
R.A. Dec.
h. m.
3 41'6
3 42'°
3 42*5
3 43'3
3 44 '2
N.i?*?
■7*7
17*8
17*8
N.i7*9
Neptune.
R.A. Dec.
h. m.
7 43'4
7 42-8
7 42'3
7 4' '9
7 4' '4
20 9
. 2°'9
N.2o*9
Table 1.
Date.
Sun.
P B L
Moon.
P
Jupiter.
P B L I. T T
12 12
Saturn.
P B
Greenwich
Noon.
Feb. 5
0 0 0 .
-13*9 — 6-4 265-3
15-8 6'6 199-5
17*5 6*9 1^3-7
19*1 7"i 67*8
— 20*6 — 7*2 2"0
0
— 14*6
-21*8
- 8*o
+ 18*2
+ i8*i
0 0 » ° h. m. h. m.
— 4*3 — 2*0 312*2 192*9 ti Ze 4 36 e
4*7 2*0 21*3 223*5 1 34 m 5 50 tti
5*1 2*0 90*3 254*2 7 22 e 2 55 e
5*6 1*9 159*1 284*9 7 39'" 2 4«
-6*o -1*9 2279 315*7 3 36c 3 17'"
— 2*3 —24*2
2 3 24*3
-2*4 -24*4
Table 2.
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Jupiter L± refers to the
equatorial zone, L.2 to the temperate zone, Ti, T2 are the times of passage of the two zero meridians across the centre of the
disc ; to find intermediate passages apply multiples of 9h 50|m, 9h 55jm respectively.
The letters m, e, stand for morning, evening. The day is taken as beginning at midnight.
The Sun continues his Northward march. Sunrise during
February changes from 7-44 to 6-51 ; sunset from 4-43 to
5-35. Its semi-diameter diminishes from 16' 15" to 16' 10".
Mercury is a morning star till February 11th, then an
evening star. Illumination, full at beginning of month, four-
fifths at end.
Venus is an evening Star, approaching its greatest elongation,
which it reaches on February 12th. Illumination one-half,
semi-diameter \2i". The planet is very favourably placed for
observation by Northern observers.
The Moon.— New 6d 5b 22mm ; First Quarter 14d 8h 34mm ;
Full 21d 2h 3mw; Last Quarter 27d 9h 15me. Apogee
12he,
N., 14"
semi-
8° E.,
7d 8hm, semi-diameter 14' 43" ; Perigee 20d
diameter 16' 47". Maximum Librations,
17d 7° S., 27d 7° W. The letters indicate the region of the
Moon's limb brought into view by libration. E. W. are with
reference to our sky, not as they would appear to an observer
on the Moon.
Star's Name.
Magnitudes.
Disappearance.
Reappearance.
Date.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.
19-3-
h. m.
h. m.
Feb. 1
BAC5737
67
—
— °
5 3° '"
285°
„ 2
71 Sagittarii
var.
6 46 in
144
7 40 tn
227
, 14
BD + 24°599
6*6
7 44«
95
—
—
, 17
47 Geminorum...
5'6
II 11 e
155
11 55*
235
, 17
BD + 27°i337
6*8
II 41 e
44
—
—
, 18 ...
BAC2383
65
1 28 m
no
2 25 m
283
, 18 ...
w** Cancri
62
4 12 e
45
4 47'
329
, 19
BD + 2I°I969
77
5 0 e
67
—
—
, 21
X Leonis
47
6 13 «
122
7 6 e
289
, 22
80 Leonis
6*4
5 45""
146
6 36 m
277
, 25
BAC4682
6-5
5 59 ">
74
6 49 m
339
, 26 ...
BAC 4923
57
4 46 in
69
5 38'"
343
, 27
b Scorpii
47
4 21 m
188
4 41 tn
219
Table 3. Occultations of stars by the Moon visible at Greenwich.
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
28
January, 1913.
KNOWLEDGE.
^9
Mars is a morning Star, but practically invisible.
Jupiter is still badly placed, having been in conjunction
with the Sun on December 18th. It is, however, just coming
into view as a morning star. Polar semi-diameter, 15i".
Day.
West.
East.
Day.
West.
1
East.
Feb. I
3 O
214
Feb. 1 5
3
0
! 4
>. 2
; i o
4
„ 16
321
0
4
». 3
©
234
,. 17
2
0
14 3»
,, 4
J
1423
„ 18
1
0
234
.. 5
2\
J
3
,, 19
2
0
34
,, 6
42
J
31
„ 20
2
0
134
>. 7
43'
J
2
,, 21
1
s
0
•I
4
„ 8
43
J
21
» 22
34
0
12
., 9
4321
J
.. 23
4321
0
,. 1°
4
J
* 2«
.. 24
42
0
1 3«
,, ii
4
J
23 >•
» 25
41
0
•1
., 12
4{
J
3
„ 26
4
0
13
M '3
24 O
13
.. 27
42
0
■3
,, 14
31
J
24
„ 28
4)
0
2
Table 4.
Configurations of Jupiter's satellites at 6h m for an inverting
telescope.
Satellite phenomena visible at Greenwich, ld 6h 24™ II. Sh.
I. ; 3d 5h 48m I. Tr. I. ; 7h 19m I. Sh. E. ; 10d 6h 56m I. Sh. I ;
I. Ec. D. ;
I. Tr. E.;
I. Sh. E.; 5h43"
24" 5h 58m 27s III. Ec. D.
II. Tr. I.; 6h14mI.Tr. I.; 6h 19"
D.; 18d 6h 3m 34s
II. Tr. E. ; 6h 13m
26d5h llm I. Sh. I.; 51
II. Sh. E. ; 27d5h45m I. Oc. K.
All the above are in the morning hours.
Attention is called to the simultaneous transits of I. and II.
on the 19th and again on the 26th.
Saturn is an evening Star, 6° South of the Pleiades. Polar
semi-diameter 8|". The major axis of the ring is 43", the
minor axis 17i". The ring is now approaching its maximum
opening and projects beyond the poles of the planet.
East elongations of Tethys (every fourth given). February
2d 6h-4 m, 9d 7h-7 e, 17d 9h-0 m, 24d 10h-2 e. Dione (every
third given). February 5'' 7h-8 m, 13d 0h'9 e, 21J 6h-0 e.
March ld llh- 2e.
Rhea (every second given). February ld 2h- 8 e, 10 3 -7e,
19d4h-7c, 28d 5h-7e.
For Titan and Iapetus, E. W. mean East and West
elongations, I. S. Inferior and Superior Conjunction, Inferior
being to the North, Superior to the South. Titan, 3d 4h-8e I.,
7d 0h-9 e W., 11" 0h-0 e S., 15d 3h-4 e E., 19d 4h-0 e I.,
23d 0h-4 e W., 26d llh-6 m S. Iapetus 19d 8h-9 e I.
Uranus is invisible, having been in conjunction with the
Sun on January 24th.
Neptune was in opposition on January 14th. Its motion
may be traced on the map of small stars which was given in
"Knowledge" for December, 1911, page 476.
Meteor Showers (from Mr. Denning's List) : —
Date.
Radiant.
Remarks.
R.A. Dec.
Feb. 5 — 10
,, IS
„ 15
,, 20
,, 20
75° + 4i°N
236 + 11 N
261 + 4 N
181 + 34 N
263 + 36 N
Slow, bright.
Swift, streaks.
Swift, streaks.
Swifl, bright.
Swift, streaks.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which
two hours will overlap with the following one. Thus the
present list includes R.A. 6h to 10h, next month 8h to 12h, and
so on. In the case of Algol variables, the time of one
minimum is given where possible, and the period. Algol,
owing to its brightness, will be given for wider limits.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Minimum.
Ii. m.
d.
h
111.
(1. h. 111.
Algol
3 2
+ 40" -6
2310 3-4
2
20
49
Feb. 2 6 27 e
RW Monocerotis
6 30
+ 8-9
9 to 10-5
1
2 1
45
RX Geminorum
6 44
+ 33 "3
8'5 to 95
1 2
5
0
RU Monocerotis
6 50
- 7 '5
9'5 to 105
0
21
3°
R Canis Maj
7 15
- 16 2
6 to 6 ■ 5
1
3
16
Feb. 6 8 j8<
RY Geminorum
7 22
+ 15 -8
85 to i°'5
9
7
13
V Camelop
7 29
+ 76 '3
95 to 12
3
7
20
RR Puppis
7 44
-41 -2
9'5 to 10-5
6
10
19
V Puppis
7 56
-49 '<>
4 to 5
1
10
54
lei). 7 10 24 ;
X Carinae
8 29
-58-9
7 8 to 8-6
0
12
59'6
Feb. 2 0 36 e
S Cancri
8 39
+ 19 '4
8-2 to 9-8
9
1 1
38
S Velorum
9 3°
-44 ■«
7'8 to 9-3
5
22
24-4
Y Leonis
9 32
+ 26-7
9'o to 106
1
16
28
WUrs. Maj
9 38
+ 56 '4
7 • 9 to 8 • 7
0
4
0-2
Table 5.
Of long period variables 0 Ceti (Mira) will reach a maximum at the end of April, when it will be invisible in the sunshine, but
it may be seen brightening early in the year.
REVIEWS.
ASTRONOMY.
The Sun. — By Charles G. Abbot, of the Smithsonian
Institution. 448 pages. Numerous illustrations. 8-in.X5-in.
(D. Appleton & Co. Price 7/6 net.)
The publication of this treatise is indicative of a most
healthy change that is coming over astronomy. All through
it exhibits an able attempt to explain phenomena, to correlate
and to classify observations. A dynamical deduction that
furnishes a clear explanation even if not the final word on (he
subject is of value. It is said that truth more easily arises
from error than from confusion. Attempting to observe with-
30
KNOWLEDGE.
January, 1913.
out a working hypothesis is like building without a scaffold,
yet it is not many years ago since an eminent astronomer
said that we do not want theory, we want facts. The promise
of the preface is well sustained. In it the author says that
the time seems ripe for collecting the splendid array of new
solar knowledge which such unprecedented activity has pro-
duced, and for discussing the probable nature of the Sun in
the light gained. All this he has done most admirably.
There are other explanations and generalizations that he
has evidently not read, hence he has not given us the whole
truth. He has, however, examined many obsolete explanations,
in the light of modern chemistry and physics and has shown
them to be wrong, such as the Laplace ring theory, and the
carbon cloud theory of the photosphere. This is especially
good work : we do not want false explanations to fossilize into
supposed firm fact, no matter how beautiful the errors may be.
The author argues conclusively that the photosphere is a
gaseous surface, but he does not seem to be aware that it is
almost certainly the limit of static equilibrium, all above it
being supported by kinetic energy ; the supporting power of
the reversing layer being the energy of volcanic projection,
and that of the chromosphere being molecular kinetic energy.
Nor does he seem to realize that if meteors have anything
to do with sunspots their function is probably similar to
the detonator of a dynamitic explosion. Meteors are, as
it were, the triggers, the dynamical rigidity of the Sun
supplying the effective energy. Altogether this is a
great book, fearless in the expression of new ideas, and
intensely sane in their advocacy. It will do much to render
solar information available, instead of remaining a lumber of
uncorrelated facts. A W R
The Star Calendar for 1913. With Revolving Chart. —By
Mrs. H. Periam Hawkins. 10-in. XlO-in.
(Simpkin, Marshall & Co. Price 1/- net.)
Users of this chart will find it one of the very best forms of
planisphere yet designed. The area of the heavens visible at
any time is shown by an oval cut in a covering card. Hence
the zenith can be recognised at once. This card is hinged at
the top, so that it can be lifted to see the whole of the stars
ever visible in England.
The chart has proved itself of great value to troops who
are studying marching by the stars. The explanations of how
to use it are very clearly described.
It would be an improvement were the North Polar Circle
drawn to show precession, and also were the Milky Way
indicated by a faint whiteness.
This is a most useful chart, and can be highly recommended.
A. W. B.
The Star Almanac, for 1913. — By Mrs. Periam Hawkins.
6 illustrations. 30-in.X24-in.
(Simpkin, Marshall & Co. Price 6d. net.)
Again Mrs. Periam Hawkins has introduced improvements
into this excellent Almanac. In addition to the star charts for
the four seasons, there is a diagram showing the North Polar
clock. She has also brought in a table of hints in connection
with marching and telling the time by the stars, the sun, and
the moon. There is all the usual information contained in a
star almanac.
The Almanac would be most valuable on the walls of any
astronomer's study or observatory.
A. W. B.
The A.B.C. Guide to Astronomy. Second Edition. By
Mrs. H. Periam Hawkins. 120 pages. 71-in. X5-in.
(Simpkin, Marshall & Co. Price 1/6 net.)
This little book is of the kind one is glad to see in its second
edition, for it is a very valuable contribution to Astronomy.
The first edition had a few misprints and slight errors from
which this edition seems quite free, as one would expect after
it had passed the keen eye of so able and accurate an
astronomer as Dr. A. C. D. Crommelin. Mrs. H. Periam
Hawkins must have read very widely in preparing this book,
for there is scarcely an astronomical idea of importance the
meaning of which is not described with the utmost clearness.
The information is brought quite up to date. Good
abstracts of the latest correlations are given, some of which
are seldom seen in any astronomical work. This attention to
broad generalizations is of the utmost importance in these
days, when the mass of detail accumulated by astronomers
threatens to bury the essential facts out of sight. The A.B.C.
arrangement is also very useful in the case of points needing
reference. The book is strongly to be recommended to the
amateur astronomer. a w R
A Primer of Astronomy. — By Sir Robert Ball. 222
pages. Numerous maps and illustrations. 7-in.X4i-in.
(The Cambridge University Press. Price 1/- net.)
This excellent little book has its value much increased in its
re-issue, by the addition of maps of the northern and southern
hemispheres, and by a new chapter of forty-two pages on
celestial objects. This chapter is written in Sir Robert Ball's
usual perspicuous style. It is exactly suited to the amateur
observer, every interesting object in both northern and
southern hemispheres being very fully described. The book
is thus rendered suitable to Africa and Australia. The
descriptions are brightened by interesting folklore. In the
older parts of the book one could have desired a few altera-
tions to bring it up to date. For instance, in the nebula of
Andromeda, which is described as showing rings elongated by
projection into ellipses, while the latest photographs leave no
room to doubt its spiral character. Some of the explanations
are also a little antiquated, and not quite in accord with
modern chemical physics.
A. W. B.
A Beginner's Star-Book. — By K. McKready. 148 pages.
70 maps and illustrations. lOi-in. X 8-in.
(G. P. Putnam's Sons. Price 9/- net.).
The author says in his Preface that this book is "in a sense
but one effort more to help those who are without technical
equipment, to claim through the unaided eyes or through simple
optical instruments their heritage in things of the sky " ; " It is
intended for the general reader," and not as a text book, but
' as a simple observational manual," and, further, " The
volume is also intended for those who wish to add to their
knowledge of the skies without aid of any kind " . . . .
" much of it is, necessarily, a recapitulation of elementary
facts; it is frankly a book for the beginner." These extracts
adequately explain the nature of this work and we heartily
congratulate the author in having so successfully accomplished
what he set himself to do. We are acquainted with most
books of this nature or aim published during the last forty
years, but we cannot recall the title of one that so well fills the
need of an elementary and progressive book on observational
astronomy for the beginner, young or old. Most err in being
either too easy or simple without the redeeming feature — given
in this book — of opportunities for promoting or satisfying
advancing knowledge ; too technical, too profuse or laborious
for the convenient and daily use of a beginner in out-door
astronomy ; or too much out of date to meet the recent
advances even in observational astronomy. To us this book
appears to be the bridge.
Beyond the data or details in the book being brought
up-to-date there can be little that is new, nor does the author
claim that it is so. The principles of the book are to encourage
the beginner to learn from the objects, not from mere book
reading ; to proceed slowly, get a good grasp of one thing at a
time, and not to attempt too much at once.
The book of one hundred and forty-eight pages is divided
into ten chapters or divisions: I, Introduction, brief but very
useful; 1 1, Objects to be seen. The Stellar World; III, Learning
to observe ; IV, Star maps ; V, Objects to be seen. The Solar
System; VI, Some Instruments of Observation; VII, An
Observer's Catalogue of Telescopic Objects; VIII, Statistical
January, 1913.
KNOWLEDGE.
31
Tables of Star Distances, and so on ; IX, Index, quite good;
X, Additional maps.
The whole-page illustrations of Stellar objects are numerous
and are scattered through the chapters. The selection of
those relating to nebulae has been judicious, representing
many of the most striking and well-known types ; as the
photographs have been excellently reproduced from the
unsurpassed photographs made at the Yerkes Observatory, it
is almost needless to say that they are of the best. The
night star- maps from pages 38 to 61 are given both in black
and white stars on opposite pages, and below each map is
added much information for use without and with small instru-
mental aid. The chief features of the Sun, Moon, Planets
and Comets are given, also with plates from photographs
taken at the Mount Wilson, Lowell and Lick Observatories.
Chapter VII consists of an alphabetical description of the
Constellations, proper names and their pronunciation ; much
useful and accurate information has been provided in a small
space of twenty-one pages: Webb, Smyth, Ambronn and
Harvard Observatory books have been utilized in forming
the catalogue. This chapter is followed by another con-
taining lists of distances of double and of variable stars,
also the photometric magnitudes of the seventy brightest
stars ; and at the end is a summary or list of books useful
to an astronomical observer. We do not think this portion is
so replete with information as the other portions of the book ;
we notice that a number of most useful elementary and
general books on Astronomy of recent publication are omitted.
For such a book of information and excellent illustrations
the price is quite moderate. There is one objection to the
book, and that is the highly-surfaced coated paper upon
a good index. The author expresses his great indebtedness
and gratitude to Mr. H. P. Hollis for his valuable help in
instruction, in suggestions, and in the revision of the manuscript.
This is a book that all who are interested in transit and time
observations should possess.
F. A. B.
which the text is printed.
F. A. B.
Their Winged Destiny : being a Tale of Two Planets. —
By D. W. Horner. 240 pages, with a frontispiece,
7i-in. X 5-in.
(Simpkin, Marshall & Co. Price 2/- net).
This is a book of convenient size for the pocket, being
nicely printed with good-sized type and on rough laid paper.
The author need hardly have remarked in his preliminary
note that the narrative was purely imaginary. The tale
reminds us of our Jules Verne days. Certain definite scientific
facts — this time the airship — are carefully worked in with the
author's imagination " run-riot." Sudden difficulties arise
and they are just as quickly and easily overcome. A journey
is made in the airship to an unknown planet and the return
to the Devonshire moors is accomplished in the thirty-third
chapter, — some of the more useless members of the party
having been left behind on the planet, — when the happy end
is achieved in the marriage of the airman and the once
little girl. F A B
Notes on the use of the Portable Reversible Transit
Instrument. — By C. E. Monro. 60 pages, 2 Plates,
8 Figures. 8-in. X 5-in.
(J. D. Potter. Price 3/-.)
The author made good use of his time by recording notes
when he was at the Royal Observatory, Greenwich, learning
the practical use of a transit instrument for the purpose of
longitude determinations. These notes, supplemented by
later experience when at Ascension, form the basis and body
of this useful little hand-book. The author states that the
book is " intended purely for the use of beginners."
Chapters I-IV. form nearly half the book and deal with the
description and principle of the instrument in considerable
detail, also with its level and mounting. Chapter V. is concerned
with the method of observation. Chapter VI. relates to the
reduction of the observations ; this chapter with appendices
II to V. constitutes the most important part of the book; the
forms and methods of reduction are those in use at Greenwich.
A theoretical explanation of the reduction of transit observa-
tions is given in Appendix I. There are two plates and eight
diagrams to aid the explanations. Pages three and four contain
CHEMISTRY.
Modem Research in Organic Chemistry. — By F. G. Pope,
B.Sc. (Lond.) 324 pages. 261 illustrations. 7 { -in. X 4^ -in.
(Methuen & Co. Price 7/6.)
In no branch of chemistry has greater advance been made
through the application of pregnant hypotheses, than in the
study of the compounds of carbon. Until about half a century
ago all was confusion, and it was not until the theory of
organic radicles had been proved workable that order began
to develop out of an accumulated mass of apparently
unrelated details, and that organic chemistry was shown to be
as capable of systematic treatment as was the inorganic branch
of the science. The series of brilliant researches which laid
the foundations of the structural formulae of carbon com-
pounds formed another stage in the advance, and now we
have reached the stage of establishing the relationship between
physical properties and the structure of different bodies.
All these successive steps in the development of organic
chemistry are sketched in an interesting preface to the book,
by Dr. J. T. Hewitt, and this forms a fitting introduction to
the subjects of which the text treats.
The book is conveniently divided into chapters dealing with
the work that has been done in connection with different
classes of compounds, such as the polymethylenes, terpenes
and camphors, the uric acid group, and the alkaloids. There
is also an interesting chapter upon the relationship between
colour and the constitution of chemical compounds. Although
much work has been done in this direction, there are still
numerous instances where no such relationship has been
discovered. In the author's opinion, however, it is not
improbable that even in such cases as these further investiga-
tion may show that certain molecular groupings are associated
with the particular vibrations giving the impressions of certain
, colours.
Research will also probably prove fruitful in establishing a
relationship between physiological properties and chemical
constitution, and in a future edition of the book a chapter
upon this aspect of the subject might with advantage be
added.
The work is well illustrated with diagrams, and, as is
essential in a book of the kind, gives full references to the
original papers. It is not intended to be an elementary text
book, but to the research student it should prove an invaluable
companion. Q A M_
Industrial and Manufacturing Chemistry [Organic). —
By Geoffrey Martin, Ph. D., M. Sc. Assisted by
Specialists. 726 pages. 249 illustrations. 10-in. X6£-in.
(Crosby Lockwood & Son. Price 21/- net.)
The name of Dr. Martin will be familiar to the readers of
" Knowledge," and its occurrence on the title-page of a
book is of itself presumptive evidence that the work will be
interesting and well written.
The aim of this book is quite different from that of Allen's
" Organic Analysis," for its object is to give a clear outline of
the numerous manufacturing processes based upon organic
chemistry, together with some details of the methods used in
the examination of the different products — sufficient to follow
the meaning of an analytical report, though not for the making
of an analysis.
The extent of ground covered may be gathered from the
fact that it deals with industries as far apart as the making
of soap and the brewing of beer, or the manufacture of
artificial perfumes and the preservation of timber. Chemistry
is now so much a matter of specialisation that no man can
hope to have a thorough knowledge of more than one or two
branches, and the chief author and editor has therefore very
32
KNOWLEDGE.
January, 1913
wisely availed himself of the assistance of specialists in the
different subjects, while at the same time keeping the general
style and arrangement the same throughout the book.
In the case of each industry there is not only a clear
description of the manufacturing processes with illustrations
of modern apparatus, but outlines are also given of methods
suggested by recent patents. Full references to the scientific
literature are also placed under each section, so that the book
must prove of great assistance to the manufacturers, patent
agents, and students engaged in industrial research, as well as
being of interest to the general reader. We notice that in the
section upon vinegar, the editor acknowledges his indebted-
ness to an article that appeared in "Knowledge" as the
source of his most recent information.
It is perhaps invidious to single out any particular sections,
but the chapter on Synthetic Rubber, by Dr. Martin, and that
on the manufacture of Synthetic and other Drugs, by Dr.
Challenger, deserve mention as being particularly good. In
some of the sections however, there are indications that the
writer has a general rather than a special knowledge of his
subject, although for the reason mentioned above this was
probably inevitable.
It is surprising how few organic industries have escaped
notice, as the present reviewer has found by test references
to the excellent index. The manufacture and valuation of
artificial organic manures, however, ought certainly to
find a place in a treatise of this kind, and the modern pro-
cesses of treating roads for the prevention of dust, with their
advantages and drawbacks would form another useful section.
Considering the enormous amount of matter in the book the
misprints are very few, and are mainly slips of a single letter.
"Zoological" for " zoogloeal " however, on page 316, is an
amusing example of a printer's interpretation of a word that
was new to him. „ ...
C. A. M.
A Second Year Course of Organic Chemistry for Tech-
nical Institutes. — By F. B. Thole, B.Sc. (Lond.).
186 pages. 7±-in. X4tj-in.
(Methuen & Co. Price 2/6.)
This little manual, which is in continuation of one that has
already appeared in the same series, deals mainly with the
chemistry of the carbocyclic, or (as they are more generally
termed), the aromatic compounds. As in the case of Part I.,
the book is simply and clearly written, and although primarily
intended for students in technical colleges it should be found
useful by all who are not far advanced in the study of organic
chemistry. The latter part of the book contains sections
dealing with practical work, including an excellent scheme
of qualitative analysis, but we venture to think that some
experimental work should have been incorporated with the
theoretical part. A very good feature is the description of
special reactions, which in many text books are merely alluded
to under the names of their discoverers, it being assumed that
the reactions themselves are common knowledge. French
text books are the worst offenders in this respect, but the
fault is not uncommon in elementary English books.
C. A. M.
GEOLOGY.
Dana's Manual of Mineralogy. — By VV. E. Ford.
Thirteenth Edition. 460 pages. 357 figures. 10 plates.
(7}-in.X5-in.)
(J. Wiley & Sons. Price 8/6 net.).
This is a revised and rewritten edition of Dana's famous
manual, first published in 1848. It is now, however, twenty-
five years since the text was last revised. Whilst the figures
and text are new, the original scope and character of Dana's
book remain, and it appeals to the same constituency as
heretofore. The chapter on petrography has been omitted
and for it is substituted a brief and general description of the
principal rock -types. The opening section on crystallography
is up-to-date, and is illustrated by much better figures than
are usual in these text-books. This is followed by an account
of the other physical characters and the chemical characters
of minerals. The treatment of determinative mineralogy is
rather full and renders the book of particular value to miners
and prospectors. In the descriptive section, occupying the
greater part of the book, the minerals are taken according to
the usual chemical classification and are treated with regard to
their chemical composition, crystallisation, general physical
properties, occurrence, and use. This section is illustrated by
many fine photographic plates of mineral groups, and is
concluded by a long and elaborate set of determinative tables.
A notable misprint is " Crypiocrystalline " for " Crypto-
crystalline " in a heading on page 176, otherwise the book is
very free from typographical errors.
The section on Rocks in connection with rock-making
minerals would have been better for revision by a competent
petrologist. Such a mistake as the inclusion of anorthosite as
a variety of syenite might then have been avoided. Possibly
this is due to the megascopic mode of treatment under which
an anorthosite might be regarded as a " syenite " since it is built
mainly of light-coloured felspars. „ ... „
On the Origin of the Himalaya Mountains. Professional
Paper — No. 12. Survey of India. — By Colonel S. G.
Burrard, R.E., F.R.S. 26 pages. lli'in.X 8-in.
(The Survey of India, Calcutta.)
This is a concise and valuable presentation of the geodetic
evidence bearing on the origin of the Himalayas, whether the
accompanying geological theory of the author be accepted or
not. The plumb-line observations in the vicinity of the
Himalayas shew an extraordinary deficiency of mass under
the Gangetic alluvial belt immediately south of the mountains.
The deflection of the plumb-line is much greater than if the
Himalayas were exercising the whole of their attraction
uncompensated. This line of low density is supposed to be
due to a deep invisible trench or channel buried beneath the
alluvium of the Ganges.
Colonel Burrard believes that in this region the sub-crustal
shell has cracked, and its northern portion has then shrunk
and moved away from the southern, giving rise to the folding
of the Himalayas. He explains the observed fact that the
folds are clearly overthrust to the south by saying that there
is only an apparent movement of the upper part of the folds
to the south. The real movement has been that of the under-
part of the folds to the north. This, of course, contradicts
the views of such distinguished geologists as Hayden,
Griesbach, and Suess, who believe that the Himalayan moun-
tain folds are due to horizontal thrust from the north against
the immobile buttress of Peninsular India.
Whether Colonel Burrard's ingenious theory will be accepted
by geologists depends largely on further geological evidence.
It seems difficult to account for the enormous quantity of
alluvium that would be necessary to fill the postulated rift, and
further evidence of the depth- of the Gangetic alluvium is
needed. Also, should we not expect similar rifts in front of
the other great folded mountain ranges of the earth ?
G. W. T.
The Structure of the Earth. — By Professor T. G. Bonney,
D.Sc, F.R.S. 94pages. 6j-in.X41-in. (The People's Books).
(T. C. & E. C. Jack. Price 6d.)
It is a difficult feat to compress the story of the earth into
the small scope of a volume of this size, but Professor Bonney
has achieved the apparently impossible with remarkable
success. Considering the limitations of space under which
the book labours the resume of geological science is fairly
complete. The work of rain, rivers, snow, ice, and the sea,
and their part in shaping the surface of the earth as we now
know it, is treated in broad outline, with a necessary avoidance
of detail. Volcanoes, earthquakes, land movements, and finally
the history of life upon the earth, are treated in the later
chapters. As a simple, concise account of geology up to date
this small book may be recommended to beginners in the
science. C W T
January, 1913.
KNOWLEDGE.
33
The Building of the Alps. — By Professor T. G. Bonney,
D.Sc, F.R.S. 384 pages. 32 plates. 16 figures.
9-in. X 6-in.
(T. Fisher Unwin. Price 12/6 net.)
From an early period, the many problems of Alpine rocks,
snowfalls and ice-streams, have attracted men of science,
especially geologists ; and Professor Bonney in this book,
which is the fruit of almost yearly Alpine wanderings over
a period of forty-five years, shews that he is a worthy
successor of the great line of de Saussure, Perraudin, de
Charpentier, Agassiz, Forbes, and Tyndall. A list of his
thirty-five journeys in the Alps is given in an appendix, along
with the titles of no less than forty-six original papers dealing
with Alpine physiographical and petrological questions.
A large part of the book, however, is really a non-technical
account of Alpine geography, although purely geological
matter occupies the first few chapters. In addition to des-
criptions of Alpine rocks and broad tectonic features, there
are interesting sections on Alpine meteorology, avalanches,
floods, fauna and flora, and the Alps in relation to man. The
last chapter, entitled " Fifty Years of Change " gives racy
reminiscences of the discomforts of travel in the Alps in the
early days.
Professor Bonney's name is identified with strongly-marked
views on certain controversial questions, especially in regard to
the origin and age of Alpine schists, and the efficiency of ice
as an eroding agent. In regard to the latter he holds and has
defended in vigorous controversy the conservative and
minority view that the work of ice is not more than abra-
sive, and is only erosive in peculiarly favourable situations.
A clear account of the dispute is given in the present volume.
This entertaining book would be the better for a topo-
graphical and geological map of the Alps, without which it
is hard to follow the descriptions of the first part. ,, ... ~
Rough Stone Monuments and their Builders. — By T. Eric
Peet. (Harper's Library of Living Thought). 172 pages.
3 plates. 22 figures. 7-in.X4£-in.
(Harper & Brothers. Price 2/6 net.)
This is a description in clear and simple language of the
great megalithic monuments which strew the seaward parts of
Europe, Asia, and North Africa. These are of perennial
interest, and in times past have given rise to curious conjectures
as to their origin, the agency of fairies, virgins, witches, dwarfs,
devils, saints, druids, and even historical personages, being
frequently invoked. These monuments range from the great
structures like Stonehenge, and the even more elaborate
nuraghi of Sardinia, and the temples of Malta, to simple
standing stones (menhirs), rock-tombs, and the barrows that
stud the English downs. The author has woven his description
of these structures, and their mode of erection, into a most
fascinating narrative, along with fact and conjecture as to the
remote civilization by which they were erected. He adopts
the theory that the monuments are due to a single race, whose
style of building was brought to different countries in the
course of a great migration or series of migrations, and finds
confirmation in the remarkable fact that in geographical
distribution these monuments occupy a vast seaboard, including
the Mediterranean coast of Africa and the Atlantic coast of
Europe. That is, they lie entirely on a natural sea route,
which would be followed by a migrating race in preference to
the more difficult land routes.
The book will be useful alike to the scientific archaeologist
and to the interested 'f popular " reader. It is written in an
attractive literary style, and is well illustrated. The only
slips noticed are that on page 10 megalithic monuments in
Italy are said to be confined to the south-east corner of the
peninsula, and on page 76 to the south-west corner; and a
" to " is substituted for " of " on page 59. r w T
METEOROLOGY.
Weather Science. — By R. G. K. Lempfert, M.A. The
People's Books No. 17. 94 pages. 15 illustrations.
6i-in.X4i-in.
(T. C. & E. C. Jack. Price 6d. net.)
The seeker of knowledge on the processes involved in our
varied weather will find in the above work, a review of the
salient features of the Science and the principles underlying
the frequent changes to which our Islands are subject. The
author is the Superintendent of the Forecast Division of the
Meteorological Office. w r I
PHOTOGRAPHY.
Nature Photography. — By Stanley C. Johnson, M.A.
115 pages. 11 illustrations. 7-in. X4}-in.
(Hazel!, Watson and Viney. Price 1/- net.)
Mr. Stanley C. Johnson takes excellent natural history
photographs himself, and it is to be expected that from his
experience he could give help to others. We are not
disappointed, for in his little book in The Amateur Photo-
grapher Library, he gives a great many valuable hints with
regard to apparatus, and to photographing river and pond
life, as well as small creatures to be found in the garden ; while
he touches on the subject of birds, which, perhaps, is the one
which has attracted the attention of photographers to the
greatest extent. Mr. Johnson alludes to the interest which
may be obtained from photographing birds in gardens, and
speaks of the usefulness, in attracting them, of the Selborne
Society's nesting boxes which he has put up. If we may
suggest one correction, it is that in a second edition, the
words " protective coloration " be used instead of " protec-
tive mimicry " for cases in which creatures are like their
surroundings. Mimicry, in its technical sense, means the
special resemblance of one creature to another. There are
some useful miscellaneous notes and a calendar with sugges-
tions as to what work may suitably be done in the various
months. ... ,, ...
PHYSICS. W' M" W'
Junior Sound and Light. — By R. W. Stewart, D.Sc, and
John Satterly, D.Sc. 227 pages. 129 illustrations.
7-in. X 5-in.
(The University Tutorial Press. Price 2/6.)
This book contains a condensed account of the rudiments
of "Sound" and "Light," together with numerous examples
and experiments. The descriptions are clear, and the book is
handy and admirably adapted for use in schools. . r
Elementary Chemical Theory and Calculations. — By
Joseph Knox, D.Sc. 103 pages. 72-in-X5-in.
(Gurney & Jackson. Price 2/- net.)
This work is only intended to be used with a textbook of
systematic chemistry. The theoretical matter usually included
in an elementary course, is fairly well covered ; the theory is
presented with the problems, which will therefore make the
book a valuable aid to the teacher, who often finds some
difficulty in making the somewhat long arguments, which
establish the formula or the atomic weight of a substance,
quite clear to the student. . „ „
A. C. E.
ZOOLOGY.
Wild Life in the West Highlands. — By Charles Henry
Alston. 271 pages. 9 illustrations. 8i-in. X5£-in.
(James Maclehose & Sons. Price 6/- net.)
This book consists of a number of articles, some of which
have been reprinted from The Scotsman and deal princi-
pally with mammals and birds. They are very interesting
reading but do not contain very much new material.
W. M. W.
The Marine Mammals in the Anatomical Museum of the
University of Edinburgh. — By Sir William Turner,
K.C.B. 207 pages. 17 plates. Over 100 figures.
9-in.X5^-in.
(Macmillan & Co. Price 6/- net.)
It is a very great advantage to students to know where
specimens are to be seen which illustrate any particular work
in which they may be engaged. The title of this book speaks
for itself and its value is obvious. The introduction is
interesting because it tells of the history of the study of
Marine Mammals in Scotland and gives hints as to differ-
entiating the various forms. There is a large number of
illustrations, the great majority of which are embodied in the
text at the exact place where reference is made to them, and
hence they are not provided with underlines. w M W
SYNTHETIC RUBBER.*
By GEOFFREY MARTIN, Ph.D., M.Sc, B.Sc.
Lecturer on Chemistry at Birkbeck College, London.
Author of "Practical Chemistry," " Triumphs and Wonders of Modern Chemistry," "Industrial and Manufacturing
Chemistry," "Researches on the Affinities of the Elements," etc., etc.
The commercial production of artificial or synthetic
rubber is undoubtedly the most important problem,
from a financial standpoint, ever faced by the chemical
industry. Compared with it such triumphs as the
successful manufacture of
artificial indigo, alizarin or
camphor become quite
small affairs.
For example, the total
value of synthetic indigo
annually produced at the
present time does not
exceed two million pounds ;
and the value of all the
coal-tar dyes annually ex-
ported by German}- only
amounts to ten million
pounds.
The world's production
of such an important
chemical as sulphuric acid
amounts to about ten
million pounds yearly,
while the enormous soda
industry probably has a value of somewhat similar
dimensions.
Yet, at the present time, crude rubber is annually
produced of a value reaching the enormous total of
thirty-four million
pounds, and were
we to add up the
value of all manu-
factured rubber
goods we would
arrive at figures far
exceeding those
given for crude
rubber, and running
into some hundreds
of millions of
pounds. Huge as
these figures are,
there is no doubt that the demand for rubber far
exceeds the supply, and for this reason the price
paid for it considerably exceeds its cost of
production. The rubber industry is a modern one.
Figure 29.
Sir William Tilden's historic samples of Isoprene and
Synthetic Rubber.
Figure 30.
Dr. Matthews' first tube of Synthetic Rubber.
From small beginnings it has grown into a vast
industry in which more than a hundred millions
of capital are invested and in which hundreds of
thousands of workmen all over the world find lucra-
tive employment.
How recent is the growth
of this industry may be
gauged by the fact that in
1830 only twenty-five tons
of rubber were exported
from America, a quantity
which had increased to
seven hundred and fifty
tons by 1850, and one
thousand five hundred tons
by 1870, against eighty-
eight thousand tons now
produced from all sources,
and representing an annual
value of thirty-four million
pounds : this great change
having occurred well within
the lifetime of a single
man. Within the last ten
years no less than seventy million pounds have been
invested in rubber plantations, and over twelve
thousand tons of plantation rubber are now
produced annually.
The selling price
of rubber has
fluctuated enor-
mously. In 1908
it once sank to two
shillings and nine-
pence per pound,
while in 1910
speculators actually
ran it up to the
fabulous price of
twelve shillings and
sixpence per pound,
and many were
the fortunes made and lost over rubber in that year,
which recalls to mind the times of Priestly, who in
1770 could only purchase it at the rate of £16 per
pound. At the present time good Para rubber sells
* See also an interesting article in "Knowledge" March, 1912, by Mr. Stanley Redgrove. The reader who wishes for a full
account of the technical literature, and the chief patents relating to synthetic rubber, will find them fully discussed in my recent
book " Industrial and Manufacturing Chemistry, Organic," published by Crosby, Lockwood & Son, London. 21/- net.
34
January, 1913
KNOWLEDGE.
35
at from four shillings to five shillings a pound.
Natural rubber could probably be produced profit-
ably at as low a price as one shilling.
Naturally, a product of such value did not escape
Figure 31.
Dr. Otto Hehner testing Messrs. Strange & Graham's
process for the production of fusel oils from starch.
the attention of the chemist, and numerous attempts
have been made to produce rubber artificially,
although until quite recently with no commercial
success. The synthetic production of rubber, in
fact, is a problem of extreme difficulty. Indeed, so
complex that no one individual could hope to get
over the difficulties ; and it was only when chemists
banded themselves together and began to work
cooperatively with this object in view that any
success was obtained.
To mention some of the difficulties, isoprene — the
volatile hydrocarbon from which synthetic rubber
was first obtained — is a liquid so volatile that it has
only to be poured from one glass to another a few-
times before it all disappears in invisible vapour ; it
could at first only be produced by imperfect methods,
and the yield was so bad that Kondakow could only
obtain ten grammes, while Ipatjew only managed to
make five grammes and Euler not two grammes !
Before much progress could be made, methods had
to be laboriously worked out for obtaining it in
quantity. The chemists employed by the great
German firm, Er. Bayer & Co., of Elberfeld, en-
deavoured to obtain isoprene from coal-tar products
in no less than fifty distinct ways, and all these ways
failed except one ! Indeed, until the chemical con-
stitution of rubber had been worked out with a
tolerable degree of certainty, its synthetic production
commercially was scarcely realisable; the recently
discovered methods of producing synthetic rubber
by a chain of processes from maize, other cereals,
potatoes or petroleum has been an immensely
laborious task, requiring years of work and a large
group of investigators. For any single man to have
attempted it would have been hopeless.
An Englishman, Greville Williams, seems to have
been the first to produce anything resembling rubber
from isoprene nearly fifty-two years ago (in 1860) ;
next, in 1875, Bouchardat, in France, definitely found
that isoprene could be converted into rubber. In
1882, 1884 and 1892, Sir William A. Tilden (Figure
33) worked out the problem much further, and
finally showed that synthetic rubber could be vulca-
nised like ordinary rubber. A large number of
investigators have since worked at the problem,
amongst whom should be mentioned Kondakow,
Wallach, Mariutza, Weber, Thiele and many others.
Kondakow especially, a Russian by birth, made
many valuable observations.
About 1903, Professor Carl Harries (Figure 34),
of Kiel University, began his epoch-making work on
rubber, and in 1904 it was in full swing. The
present writer was at that time studying at Kiel
University and well remembers how Professor
Harries installed electrical apparatus for producing
ozone in quantity in some of the rooms, while every-
where danger notices were posted up " Dangerous
to Life — Do not Touch," evidently to prevent in-
quisitive students from electrocuting themselves with
the powerful high tension currents or blowing them-
selves up with the explosive ozonides which at that
time he was producing in quantity-
Professor Harries is in many ways an interesting
personality. He is reputed to be a man of enormous
wealth, and only a few years ago he bought the
Kaiser's famous racing yacht, the " Meteor " ; he is
Figure 32.
Tubes containing Isoprene polymerising to rubber in Messrs.
Strange & Graham's laboratory.
36
KNOWLEDGE.
January, 1913.
a well-known figure in German aristocratic circles.
At the present time he, it is believed, is working in
conjunction with some of the world-famous German
chemical firms with the object of producing synthetic
rubber commercially.
Harries' work was really epoch-making in every
way. He indicated the probable constitution of
rubber, reducing it to a simple formula ; he showed
how to prove chemically whether a substance was a
true rubber or not, and indirectly his researches
drew the attention of the chemical world to the
enormous prizes to be won by the successful
synthetic production of rubber. The stimulus
produced by Harries' work, coupled with the high
price of natural rubber, soon reflected itself in
industrial chemical circles, and from 1907 onwards
the patent literature bears witness to the extraordinary
activity reigning in this department of chemistry.
Among the large continental firms which took
part in the race were Fr. Bayer & Co., of Elberfeld,
Germany, the Badische Aniline und Soda Fabrik, of
Ludwigshafen, and Messrs. Schering, of Berlin. A
photograph of Dr. Fritz Hofmann, who directed the
work of the chemists of Fr. Bayer & Co., is shown
in Figure 35.
Meanwhile in England the firm of Messrs. Strange
and Graham united with a number of chemists of
note with a view to produce synthetic rubber, and
so the " Synthetic Products Co. " of London came
into existence. No less than fifteen chemists and
bacteriologists were thus united at work on the
problem. Foremost among these chemists must be
mentioned Dr. F. E. Matthews (Figure 36), of the
firm of Strange & Graham, who suggested the fusel
oil route for the manufacture of isoprene and who
was the first to discover and patent the sodium pro-
cess of polymerising isoprene quantitatively into
rubber, thereby making possible the commercial
manufacture of synthetic rubber.
Mr. E. Halford Strange (Figure 37), head of the
firm of Strange & Graham, organised the work of
the group and brought into existence the company ;
Professor W. H. Perkin, junr., F.R.S. (Figure 38),
Professor of Chemistry at Manchester University,
with his two assistants Mr. Harold Davies and Dr.
Weizmann, perfected the chemical processes
ployed in pro-
ducing isoprene.
Professor Perkin
is the son of
the famous Sir
William Perkin,
who brought into
existence the
aniline dye in-
dustry, and made
a fortune out of
it, although sub-
sequently the
colour industry
went over into
German hands. Table 6.
Professor Perkin, who has produced an enormous
quantity of research work of the highest quality in
pure chemistry, has evidently inherited the practical
abilities of his father ; for he, a few years ago,
invented the " non-flam " process for permanently
fireproofing cotton goods.
Professor A. Fernbach (Figure 39), of the Pasteur
Institute, succeeded in producing acetone and fusel
oils cheaply by a process of fermentation from
cereals, thereby producing the raw material for the
manufacture of synthetic rubber.
Later, the group was joined by Sir William
Ramsay (Figure 41), the famous discover of Argon,
Helium and other inert atmospheric gases ; it will be
recollected that Sir William Ramsay quite recently
resigned his professorship of chemistry at University
College, London, about the same time that the
company was formed.
Sir W. A. Tilden (Figure 33) also joined the com-
pany as a consulting chemist. It will be recollected
that Sir William Tilden nearly thirty years ago
had performed some epoch-making work on isoprene,
and the formation of synthetic rubber from it.
Before we can give an account of the chemical
processes for producing synthetic rubber commerci-
ally, we must explain its chemical constitution.
The net result of a vast amount of research work
performed by various investigators, has been to show
that when certain unsaturated hydrocarbons contain-
ing the grouping : C : C.C : C : are allowed to
polymerise (i.e., condense into more complicated
bodies) they form a series of caoutchoucs or rubbers
which possess many of the properties of the best
sorts of natural rubber, including the power of
vulcanising. Natural rubber is the rubber produced
by the polymerisation of one particular hydrocarbon
called isoprene ; but the chemical sisters and brothers,
so to speak, of isoprene all produce rubbers of
different sorts, some of them with new and valuable
properties for special purposes.
The hydrocarbons from which technical synthetic
rubber have been formed are : —
Butadiene (Ervthrene, Divinyl), CH2 = CH — CH
= CH2.
fi-Methyl butadiene (isoprene, methyl divinyl),
em- CH2 = C(CH8)-CH = CH2
CH,=CH-CH=CH5
— >
CH2=CH-CH=
Butadiene.
CH2=C(CH„)-CH
CH,
= CH.;
CH2=CH-C(CH3) = CH2
/3- Methyl butadiene (isoprene).
CH2 = C(CH8)-C(CH3)=CH2
CH2=C(CH3)-C(CH3) = CH2
|3-7-Dimethyl butadiene
(di-isopropylene, dipropylene).
CH2-CH=CH-CH,
I I
CH2-CH = CH-CH2' )
Normal butadiene rubber
CH2-C(CH3) = CH-CH..
I I
CH2-CH = C(CH„)-CH;
/3-Methyl butadiene rubber
(isoprene rubber, natural rubber)
CH2-C(CH«) = C(CHa)-CH.,
I I
CH2-C(CH8) = C(CHa)-CH2
/S-7- Dimethyl butadiene rubber
(dipropylene rubber).
f}-y- Dimethyl
butadiene (di-
isopropylene, di-
propvlene), CH2
= C(CH8)— C
(CH8) = CHa.
The first sub-
stance is at or-
dinary tempera-
tures a gas,
but readily con-
denseson cooling
to a volatile
liquid. The other
two substances
are volatile
From a photograph by Lafayette, Ltd.
Figure 33.
Sir William A. Tilden.
From a plwiograph by F. Urbahus.
Figure 34.
Professor Carl Harries.
From a photograph by Herrmann &* Klein
Figure 35.
Dr. Fritz Hofmann.
From a photograph by Speaight, Ltd.
Figure 36.
Dr. F. E. Matthews.
From a photograph by
Figure 37.
Mr. E. Halford Strange.
Hazel.
Figure 38.
Professor W. H. Perkin, Jin
Figure 39.
Professor A. Fernbach.
Fiom a photograpn oy Lafayette, Lid.
Figure 40.
Mr. Charles A. Pirn.
Figure 41.
Sir William Kamsay.
37
38
KNOWLEDGE.
January, 1913.
colourless liquids, boiling at 36°C and 71°C
respectively. Higher members of the series are
also known.
The polymerisation* may be regarded as taking
place as shown in Table 6.
And, in general, a rubber derived from a homo-
logue of butadiene, such as CH2=CX — CY = CH2,
would produce rubbers of the formulae : —
,CH2-CX = CY-CH2\ ,CH2-CX = CY-CH.,N
^CH2-CX = CY-CH2
and
I
CH2-(
-CY = CX-CH2' x
Once the hydrocarbons butadiene or isoprene are
obtained, it is the simplest thing in the world to
turn them into rubber.
All that has to be done is to introduce into the
mobile liquids a small amount (five per cent, or less)
of thin sodium wire and warm gently for some hours
or days, when the products will change from liquids
into solid masses of rubber. Figure 32 shows the
process being carried out on the small scale. The
sodium acts " catalytically" i.e., it is not changed by
the process and may be recovered afterwards and
again utilised. It induces change without itself
changing. Simple as this process seems, it took
years of research to discover it, and then it seems to
have been discovered almost simultaneously and
independently by Dr. Matthews and Professor Carl
Harries. The English investigator, however, owing
to a priority of discovery of only about three months,
succeeded in securing the patent world-rights. The
discovery was alighted on almost as an accident. It
occurred to Dr. Matthews that it would be of interest
to study the action of sodium upon isoprene.
He, therefore, sealed up some isoprene with
sodium in the tube shown in Figure 30 and set it
aside in July, 1910. In the month of August, during
a holiday, he was compelled suddenly to return to
London, and on looking at his tube found that the
liquid isoprene had now become viscid and contained
a proportion of a remarkably good variety of rubber.
The tube was again set aside, and in September was
found to contain a solid mass of amber-coloured
rubber. The patent was applied for on October
25th, 1910, only three months before the German
application.
Before this time other methods were known of
polymerising isoprene, notably the simple process of
heating alone, but none of these methods can com-
pare either in rapidity or certainty with the sodium
method. Fr. Bayer & Co., of Elberfeld, simply
heat under pressure, which certainly polymerises the
isoprene. To show what an important advance this
represents I will quote the words of Dr. Fritz
Hofmann (who directed the research work on rubber
for the German firm of Fr. Bayer & Co.), as pub-
lished in his Freiburg address a few weeks before
the publication of the sodium process. He says : —
" The obtaining of isoprene in quantity did not end our
troubles, on the contrary, they now began in earnest, for now
arose the problem of converting this benzine-like liquid into
the tough, elastic, and resistant colloid known as rubber.
" At first sight nothing seemed simpler ; for do we not read
in Beilstein's Chemistry that ' isoprene is converted into
rubber by treating with hydrochloric acid' ? All we had to do
then, was to add some hydrochloric acid to our isoprene ;
this we did, but alas! not a trace of rubber did we obtain,
merely an oily chloride.
" Next we tried the action of light, which Wallach has
shown to turn isoprene into a rubber-like substance. Hut
such experiments require much patience when one is waiting
for synthetic rubber, and at last got on our nerves : for after
standing one and a half years in the light our isoprene had
only turned into a fluid of the consistency of a thin syrup —
evidently a perfectly useless technical process. So that now
after months of experimenting we had obtained no useful
result. In desperation we next tried acting on our poor
isoprene with every possible and impossible chemical and
physical influence in order to induce it to polymerise — but to
our sorrow it obstinately refused to thicken !"
In fact, such great difficulties were experienced by
German experimentalists in causing isoprene to
thicken into rubber, that we actually find Professor
Carl Harries in 1907, and even in 1910, doubting
whether Tilden ever really obtained rubber from
isoprene. But like many eminent scientific men
Professor Harries is nothing if not a critical doubter.
So that the mere fact that he doubted whether
;|: As a matter of fact the polymerisation is a much more complex matter than this. Thus sticky or liquid lower
polymerides are first formed, and the final polymerisation product is formed gradually by further condensation.
Also Harries has shown (Annalen, 383, 157-
229) that different rubbers are obtained by
using different polymerisation agents, e.g., when
butadiene is polymerised by heating alone or
with acetic anhydride, it yields a " normal
butadiene rubber," (C<Hi2)n, while when poly-
merisation is effected by sodium wire it yields
quite a different rubber, called " sodium butadiene
rubber." In a similar manner several isomeric
rubbers are obtained by polymerising isoprene
and dimethyl butadiene respectively. Thus,
for isoprene rubber (natural rubber) Harries
suggests (Annalen, 383, page 187) the presence
of three isomerides, which have the double
linkage in a different position, as shown in
Table 7.
Moreover, each of these isomerides may have several stereoisomerides. It will be seen that CH2— CH — CH— CH2
according to Harries' views the basis of rubber is the hydrocarbon cyclopentadiene (1 : 5) which | I
contains a ring of eight carbon atoms:— CH2 — CH = CH — CH2
Pickles (Jour. Chem. Soc., 1910) and Ostromisslensky (Jour. Russ. Phys. Chem. Soc., 1912, 44, 204-244), suggest rings
containing more than eight carbon atoms.
C.CH,
HC CH2
I I
H..C CH.,
I !
H2C CH
\^
CH:,.C
Normal isoprene
rubber.
C.CH.,
S\
HC CH
I II
H2C CH
I, I
H 2 C CH,2
\/
CH;,.CH
C.CH.,
HC CH
I I!
H2C CH
I I
H.,C CH.CH;t
CH2
Isomerides mixed with nornKi] rubber.
Table 7.
January, 1913.
KNOWLEDGE.
39
synthetic rubber had ever been obtained by Tilden,
years before he had himself begun to experiment
with this object, need not cause much surprise;
more especially as all organic chemists look with
CH
CH,
CH
CH
CH
Sahatier and
Senderens.
CH,
CH
CH2
CH2
CH,
CH,
OH
Phenol.
NHiOCtCHjh.CO.NH,
Amide of adipic acid.
CH
OH
HCIO
NH.,.(CH.,)4.NH,
Tetramethylene
diamine.
CH,I+KOH
>■
Ag,0
(CH,),
HO'
>N.CH,.CH,.CH.,.CH.,.N
#
(CH,),
heat.
OH
which have been suggested as a starting point may
be mentioned : —
(1) Coal Tar. (2) Carbohydrates such as starch,
sugar or wood. (3) Petroleum. (4) Turpentine oils.
We will deal with methods
of obtaining isoprene or bu-
tadiene from these sources,
taking each in turn. Dr.
Fritz Hofmann, of the firm
of Fr. Bayer, of Elberfeld,
chose coal-tar as his starting
point, and worked out a
method of producing both
isoprene and butadiene in
quantity from this substance.
To produce butadiene,
first of all phenol is isolated
from coal-tar and
then is converted
by the following
series of opera-
into buta-
(See Table
COOH CH,
COOH
~>
Adipic Acid.
I(CH,)3. N-(CH,)4 -N(CH3):i I
■> CH, = CH-CH = CH>+2N(CH,),+2H.,0.
Butadiene.
CH,
I
c
Table 8.
grave suspicion on the labours of their fellow-workers.
However, Figure 29 will set the matter at rest ;
for therein is shown a photograph of Sir William
Tilden's actual sample of synthetic rubber, which
was obtained by the complete polymerisation of
isoprene obtained by him no less than thirty years
ago. The liquid isoprene had taken about twenty years
to spontaneously solidify into rubber of good quality !
This fact settles all argument about the matter, and
there are still a great many
people who distinctly remember
him showing a sample of syn-
thetic rubber, at a meeting of
the Birmingham Philosophical
Society on May 18th, 1892,
the paper being published in
the Chemical News, Vol. LXV.,
page 265 (1892).
After the foregoing remarks
it will be seen that the com-
mercially successful production
of synthetic rubber depends
entirely upon the possibility
of producing cheaply the hydro-
carbons, butadiene and isoprene
— for both yield excellent
rubbers.
It must be obvious that the
materials we start with
tions
diene.
8.)
If,
however,
isoprene is re-
quired, it also is obtained from coal tar by isolating
paracresol from it and then treating it to the series
of reactions shewn in Table 9.
The /3-Methyltetramethylene diamine thus pro-
duced is converted into isoprene by heating it with
caustic potash, water, methyl alcohol, and methyl
chloride, CH3C1, in an autoclave for twelve hours at
100° C, whereby the compound C1(CH3)3N.CH2.
CH(CH3).CH2CHa.N(CH.s)3Cl is produced. This
raw
must not only be very cheap
but must also be obtainable in
practically unlimited quantity,
if we are to produce a synthetic
rubber capable of competing
in any way with natural rubber.
Among the raw materials
HC
HC
CH
Sabatitr and
r* H Senderens.
c
I
OH
jiJ-Cresol from
coal-tar.
CH,
I
CH
CH, CH,
CH, CH,
CH
I
OH
CH,
I
CH
CH,
CH,
CH,
I
NH,— CH,— CH-CH,— CH,— NH,
/3-Methyltetramethylene diamine
COOH CH,
COOH
/3'Methyladipic
acid.
CHS
I
/CH— CH,
?H* CH,
I
CO.NH, CO.NH:
Amide of /3-Methyl-
adipic acid.
Table 9.
40
KNOWLEDGE.
January, 1913
is converted into the base by replacing the CI with
OH by treating with silver oxide in the usual
manner. The base, when distilled, breaks up into
isoprene, thus
(CH3) .(CHS),
";n.ch2.ch(ch:)).ch2.ch2.n^ >-
H(T
OH
CH2 = C(CH:i)— CH=CH2 + 2N(CH»)S + 2H2().
Isoprene.
Homologues of isoprene ma\- be produced in a
similar manner.
By this paracresol method Hofmann produced
gallons of isoprene, which was converted into rubber
by polymerising by heating, and the rubber thus
obtained was made into a motor-car tyre. One
driving wheel of a motor-car was fitted with a tyre
made of the best natural Para rubber (the best
natural rubber known), and the other with this
synthetic rubber ; after six months' hard wear the
Para tyre was badly worn, while the synthetic tyre
was practically untouched — a conclusive proof of
what can be done with synthetic rubber.
Quite recently (see The Daily Mail, September
11th, 1912,) in New York, two excellent specimens
of synthetic rubber tyres, one a heavy five-and-a-half-
inch and the other a four-inch tyre, were exhibited
before a gathering of the world's chemists, by
Fr. Baver & Co.
(To be continued.)
NOTICES.
SECOND-HAND APPARATUS.— A very useful catalogue
of second-hand apparatus and accessories has been issued by
Messrs. H. F. Angus & Company, of 83, Wigmore Street,
London. It specially deals with microscope stands, objectives,
and eye-pieces by all the well-known makers. There are also
lists of accessories, and of other instruments, such as tele-
scopes, field-glasses, spectroscopes, and photographic lenses.
It is practically certain that if there were not facilities for the
obtaining of apparatus at a cheap rate many useful experi-
ments would remain unmade, and it is a great advantage to
workers that Messrs. Angus will give a written guarantee that
any second-hand instrument which they sell has been tested
and adjusted so that it will work as well as ever it did.
MESSRS. W.WATSON & SONS, LTD.— We have pleasure
in announcing that Messrs. W. Watson & Sons have moved
their electro-medical department from their establishment in
High Holborn (which they have occupied for more than fifty
years) to their new premises at 184, Great Portland Street, W.,
where, owing to the greater scope, this section of their business
can now be carried on more advantageously than hitherto.
For not only are there show-rooms for the display of electro-
medical apparatus in every branch, but a testing laboratory
has been provided where all the appliances will be carefully
examined and checked on their receipt from the works at
High Barnet before they are despatched to customers.
LANTERN SLIDE GALLERY.— Mr. J. H. Steward has
opened at 406, Strand, a new lantern slide gallery, wherein
can be seen at any moment two thousand slides, illuminated
by electric light. Here will be found a good selection of
slides of scientific interest, in addition to full series of photo-
graphic views of excellent quality, both plain and coloured,
from all parts of the world. We noted specially a fine series
of astronomical slides, produced by the Woodburygravure
process. We welcome this addition to the very small number
of lantern slide galleries in London.
NOTES ON NEW BOOKS.— From Messrs. Macmillan
and Company comes an illustrated list with descriptive
notes of their new and forthcoming books. The short
paragraphs have advantages in some ways over reviews,
because the publisher can say in them exactly what he wants
his prospective readers to know about the book.
THE ROYAL INSTITUTION.— The following are the
Lecture arrangements at the Royal Institution before Easter : —
Professor Sir James Dewar, a Christmas Course of Six
Experimentally Illustrated Lectures, adapted to a Juvenile
Auditory: 1, Alchemy; 2, Atoms; 3, Light; 4, Clouds;
5, Meteorites ; 6, Frozen Worlds. Professor William Bateson,
Six Lectures on "The Heredity of Sex and some Cognate
Problems." Professor H. H. Turner, Three Lectures on the
Movements of the Stars: 1, "The Nebular Hypothesis";
2, " The Stars and their Movements " ; 3, " Our Greater
System." Mr. Seton Gordon, Two Lectures on " Birds of the
Hill Country." Professor B. Hopkinson, Two Lectures on
" Recent Research on the Gas Engine." Sir Sidney Lee,
Three Lectures on " The Dawn of Empire in Shakespeare's
Era." Mr. W. B. Hardy, Two Lectures on " Surface Energy."
Dr. H. Walford Davies, Three Lectures on Aspects of
Harmony: 1, " Chord Progression " ; 2, " Added Dissonance " ;
3, "The New Whole Tone Chord and its Predecessors."
Professor Sir J.J. Thomson, Six Lectures on " The Properties
and Constitution of the Atom." The Friday Evening Meetings
will commence on January 17th, when Professor Sir J. J.
Thomson will deliver a Discourse on " Further Applications
of the Method of Positive Rays." Succeeding Discourses
will be given by Professor J. O. Arnold, Mr. George M.
Trevelyan, Sir John Murray, Professor Andrew Gray, Mr.
Spencer V. Pickering, Mr. C. T. R. Wilson, Professor the
Hon. R. J. Strutt, and Mr. A. E. H. Tutton.
CLASSES IN PHOTOGRAPHY.— Mr. Edgar Senior's
work at the following various educational centres begins on
the dates set forth below.
Battersea Polytechnic. — Tuesday, January 14th.
South Western Polytechnic, Manresa Road, Chelsea.- —
Monday, January 13th.
The London Central Y.M.C.A., Tottenham Court Road. —
Friday, January 10th.
LANTERN SLIDES.— The new catalogue of lantern
slides issued by Messrs. Flatters & Garnett, Ltd., of Dover
Street, Manchester, consists of one hundred and thirty-six
pages, and many of the subjects in the list are from negatives
illustrating natural history and cannot be obtained elsewhere ;
such, for instance, as the series of British birds, nests and eggs
by Mr. Stanley Crook, and the British Plant Associations
photographed by Mr. W. B. Crump. We can give the highest
praise to the specimen slides which Messrs. Flatters and
Garnett have submitted to us for review. The bird-photo-
graphs are excellent, as are the plant studies, and all of them
should prove extremely useful to lecturers who have not the
opportunity of making their own slides, or who wish to fill up
gaps in their series. Teachers, who as a rule are not blessed
with large means, should be able to take advantage of the
slides, as they are by no means expensive. The examples
sent to us are contained in one of Messrs Flatters & Garnett's
special mahogany dispatch boxes, which we commend to our
readers, and which are described on the cover of the catalogue.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
FEBRUARY, 1913.
SYNTHETIC RUBBER.
By GEOFFREY MARTIN, Ph.D., M.Sc, B.Sc.
Author of
Lecturer on Chemistry at Birkbeck College, London.
Practical Chemistry," " Triumphs and Wonders of Modern Chemistry," "Industrial and Manufacturing
Chemistry," "Researches on the Affinities of the Elements."
(Continued from page 40.)
We now come to discuss methods for obtaining
butadiene and isoprene from starch, which, next to
cellulose or wood, is the most abundant of all
vegetable material, occurring in cereal grains and
potatoes.
There are several
methods of trans-
forming starch into
isoprene. One of
the processes now
actually being
worked is known
as the " fusel oil "
route, and was first
suggested by Dr.
F. E. Matthews, of
the Synthetic Pro-
ducts Company.
Maize or potatoes
are made into a
mash with water,
which is then inoc-
ulated with new
varieties of bacteria
discovered by Pro-
fessor A. Fernbach,
of the Pasteur In-
stitute of Paris,
and the whole is
allowed to ferment for about a week in a special vat
(see Figure 31), when about forty-two per cent, of the
starch contents were found by Dr. Otto Hehner, the
well-known analyst, to have been converted into fusel
Figure 42.
Messrs. Strange & Graham's Apparatus for the production of butadiene
from butylene dichloride.
oils, the main constituent being butyl alcohol.
Figure 45 shows the vats now being erected by the
Synthetic Products Co., for the manufacture of fusel
oil on a commercial scale. By varying the condi-
tions of fermenta-
tion acetone can be
obtained at the
same time in large
quantities.
Next, the fluid is
removed from the
vat and is distilled,
whereby the fusel
oils and acetone
are separated from
the watery residues.
Next, into the
heated fusel oil a
stream of dry
hydrochloric acid
gas is passed
(which, as every
schoolboy knows,
is made by the
action of sulphuric
acid on common
salt), when mono-
chlorides are
formed thus : —
CH„CH2CH.2CH.,C1 + H20
Rutyl Chloride. Water.
CH:,CH2CH,CH,OH + HC1 =
Butyl Alcohol. Hydrochloric
Acid Gas.
The butyl chloride thus obtained is then treated
41
42
KNOWLEDGE.
February, 1913.
with chlorine gas to convert it into dichlorides,
thus : —
CH3CH2CH2CH2C1 + CI,. = CH.sCHClCH2CH2Cl+ HC1
Butyl Chloride.
Chlorine
Gas.
Butylene Dichloride.
Hydro-
chloric Acid.
Bichlorides of the formulae CH3CH2CHC1.CH2C1
and CH2C1.CH2CH2CH2C1. are simultaneously
formed.
If chlorine acts unrestrainedly upon the butyl
chloride other products in addition to dichlorides are
produced. A special apparatus had to be invented
so as to remove the dichloride as rapidly as it is
formed. The apparatus of Mr. Charles A. Pirn (see
Figure 40) is shown in Figure 43. The butyl
chloride is boiled in the flask until the chlorinating
chamber is full of vapour and liquid drops from the
end of the reflux condenser, while a stream of dry
chlorine is passed in rapidly, care being taken, how-
ever, that the butyl chloride remains in excess.
During the whole operation the apparatus must
stand in a good light, and on dull days ultra-violet
light from a mercury lamp is used to facilitate
chlorination. As fast as the higher-boiling di-
chloride is produced it drops back into the boiling
flask, and as this is provided with an efficient
fractionating column, only the lower-boiling butyl
chloride can pass into the chlorinating column ; the
dichlorides are thus removed by gravity from the
sphere of the action of the chlorine and thus escape
further chlorination. The liquid in the flask is
finally fractionated and the dichlorides isolated in a
pure condition.
These dichlorides are next passed over hot soda
lime contained in a tube heated to 470°C as shown
in Figure 42; the soda lime abstracts hydrochloric
acid from the dichlorides and produces butadiene
thus : —
Hot Soda-lime.
CH3CHC1CH2CH2C1 - — — > CH2 = CH-CH=CH2
Butylene Dichloride. iliLl Butadiene.
The issuing butadiene is a gas, but on cooling it
condenses to a colourless liquid, and so is easily
separated by passing the vapour coming from the
hot soda-lime through a vessel immersed in a freez-
ing mixture. A similar method is used for making
isoprene from amyl alcohol — as we will see
presently.
Professor Perkin also proposes to produce buta-
diene from aldehyde, CH3CHO, which is produced
from alcohol merely by oxidising it — the alcohol
being obtained from the starch of cereals or potatoes
by ordinary fermentation with yeast. The aldehyde
is treated with a dilute solution of potassium car-
bonate (washing soda, soda ash) wherebv aldol,
CH8CH(OH)CH2CHO, is formed. This "is then
reduced with nascent hydrogen and yields butylene
glycol, CH8CH(0H)CH2CH2C1., which is then
converted into 1:3 dichlorobutane, CH3CHC1.CH2
CH2CL, which yields butadiene when passed over
hot soda lime as above described. Alcohol at present
costs about threepence per pound.
The butadiene, no matter by which of these pro-
cesses it is produced, is then converted into butadiene
rubber by warming with sodium in the manner pre-
viously described.
The formation of butadiene rubber is thus repre-
sented by Prof. Harries, of Kiel : —
CH2=CH-CH=CH2
CH2=CH-CH = CH2"
Butadiene.
Sodium.
/CH2-CH = CH-CHa
->(' i )
r\CH2-CH = CH-CH/x
Butadiene Rubber.
A yellowish mass is thus obtained, which is washed
with alcohol or heated with steam to drive off any
unchanged hydrocarbon. It can be vulcanised to
produce an excellent rubber.
It will be noticed that in the two processes above
described the raw materials are : maize or potatoes —
the starch of which at present costs less than one
penny a pound ; common salt (to produce the chlorine
and sodium) ; and lime. The total cost of the raw
materials does not exceed twopence per pound. In
fact, Mr. Strange calculates that synthetic rubber
could be produced at fourpence to sixpence per
pound. I understand that quite recently Professor
Fernbach has further developed the bacteria, so that
they will ferment wood in the form of cellulose —
instead of maize or potatoes — and produce a fair yield
of acetone and fusel oil. This advance, however,
has still to be utilised commercially — so that it
remains an interesting laboratory experiment.
Instead of starting with butyl alcohol, which is the
main constituent of wine fusel oils, but which can
now be obtained in almost unlimited quantities by
the fermentative processes introduced by Professor
Fernbach, we can start with isoamyl alcohol, which
is the main constituent of the fusel oils obtained in
spirit manufacture from cereals or potatoes.
/soamyl alcohol has the constitution (CH3)2CH
CH2CH2OH. It is first converted into the chloride
(CH3)2CHCH.2CH2C1. by dry hydrochloric acid gas,
and the monochloride thus produced is then con-
verted into a dichloride by treating with chlorine gas
in a Pirn's apparatus as previously described under
butyl alcohol. Three dichlorides are thus pro-
duced, namely: isopropylethyltrimethvlenedichloride,
(CH3)2CHCHC1.CH2C1. (B.P. 142) ; gem-dimethyl-
trimethylene dichloride, (CH3)CC1.CH2CH2C1. (B.P.
152-155) and /3-methyltetramethvlene dichloride,
CH2C1.CH (CH3) CH2CH2C1. (B.P.170-172). These
dichlorides when passed over hot soda-lime produce
isoprene, the soda-lime extracting the elements of
hydrochloric acid, thus : — ■
CH3
CH;,
>C-CH2-CH2C1.
Hot Soda.
Lime.
CH;,
->
CH
//
C-CH = CH2
CI.
Butylene Dichloride. Isoprene.
The isoprene is then converted quantitatively into
rubber by metallic sodium.
However, as amyl alcohol fusel oils are to-day
quoted at one hundred and forty pounds a ton, and
have a host of other useful applications, it is
doubtful whether such a process would survive com-
petition with the butyl fusel oil process which can
February, 1913.
KNOWLEDGE.
43
be produced at thirty pounds a ton, by Fernbach's
new process.
It should also be noted that isoprene may be
obtained from acetone in several ways. For example,
Fr. Bayer & Co., of Elberfeld, propose to manufacture
isoprene by condensing formaldehyde with acetone
in the presence of weak alkali, to form 2-ketobutanol
and other products :— CH3COCH.,+ CH20 = CH3
COCH2CH2CH2OH. From this water is split off
and methylene acetone is produced : — CH3COCH
= CW.Z, and from this
isoprene is produced. Dr.
F. E. Matthews has also
worked out methods for
changing acetone into
isoprene. However, these
methods do not appear to
be commercially remunera-
tive.
To sum up, then, three
practical methods have
been devised for obtaining
rubber from starch : —
(1) From Fernbach's
fusel oil — consisting princi-
pally of butyl alcohol and
costing about thirty pounds
to forty pounds per ton ;
(2) from industrial alcohol
through aldehyde, alcohol
costing threepence per
pound ; (3) from fusel oils
obtained from spirits —
which at present cost about
one hundred and forty-
pounds per ton.
The raw material is in
every case obtained by
agricultural processes.
Table 10 represents the
new industries and their
relation to the old. (See
page 44.)
Since the whole chain
of industries mentioned in
this Table ultimately rests
rubber starts from raw petroleum. From petroleum
both butadiene and isoprene have been obtained by
special " cracking " processes — for example, passing
it over red hot surfaces impregnated with special
"contact" substances, and, indeed, at the present
time the writer is aware of a vast amount of secret
research going on with this object in view.
Somewhat more promising are chemical processes ;
to give an example, according to one suggested
process the petroleum is fractionated, and a product
containing isopentane,
(CH3)2CH.CH2CH3, is
isolated. This is then
treated with chlorine and
a mixture of dichlorides,
C5H10C12, are obtained.
These are then sent over
hot soda lime, when iso-
prene is produced thus : —
CH3.
NcCLCHgCHgCl.
CH/
A dichloride from isopenlane.
Mr.
Figure 43.
Pirn's Apparatus for
upon agriculture as a
basis, it would seem that a good time is coming for
farmers.
So far we have discussed the methods of producing
rubber from starch, in the form of cereals or potatoes.
It must not be forgotten, however, that wood could
be used as a starting point for producing mashes
capable of fermentation. For example, several
processes are known, and are even worked on a
limited scale, of converting wood into sugars, which
can then be fermented much in the same way as
the starch mashes referred to above. Although
possible, however, it is improbable for many reasons
that such processes will be able to compete with
those which use starch as their starting point.
The next promising method for producing synthetic
CH8
I
CH.. = C-CH = CH,
Isoprene.
By treating other frac-
tions of petroleum in a
similar manner not only
isoprene but also butadiene
and dipropylene can be
obtained and converted in-
to rubbers in the usual way
by treating with sodium.
There still remains to be
considered the production
of rubber from turpentine
oils. When these are
passed under certain con-
ditions over hot contact
surfaces isoprene may be
produced in quite considerable quantities, and a
great many patents have been taken out for im-
proving the yield.
The general consensus of opinion among technical
chemists, however, is that the raw materials are too
expensive to allow a commercially remunerative
synthetic rubber to be produced from turpentine oil.
Before leaving the subject of synthetic rubber
manufacture, however, I must say a few words about
rubber obtained from still higher homologues of
butadiene than isoprene.
First of all there is the hydrocarbon fl-y -dimethyl-
butadiene also known as dipropylene and isopropy-
lene. This substance is simply butadiene in which
C. A. Pirn's Apparatus for the fractional
distillation of butylene dichloride.
44
KNOWLEDGE.
February, 1913.
two hydrogen atoms are replaced by two methyl
groups, thus : —
CH2 = CH-CH = CH2 CH2=C (CH,)-C (CH,) = CH,
Butadiene. /i-7-Dimethyl butadiene, dipropylene*--
isopropylene.
Dimethylbutadiene is also a volatile liquid, boiling
at 71°C, and can be turned into a rubber by treating
with sodium, thus : —
CH., = C(CH,)-
CHS=C(CH,,)-C(CH:,I
Dimethylbutadiene.
C(CH;,)=CH:i
CH,
.odium. /^Hi CICH;:)-
VCH2-C(CH,) =
Dimethylbutadi
The rubber thus produced — a white tough leathery
mass — can by vulcanisation be made to yield a
beautifully elastic substance; unfortunately, however,
Agriculture
ethyl and even phenyl and naphthalene radicles
replace the hydrogen of butadiene. So long ago as
1904, Klages and Lauk showed that phenyl isoprene,
CH2 = C (CH3)-C (C«HB) = CHa could be made to
produce ebonite-like bodies on vulcanisation.
There is thus opened up a rich field of research in
the production of these " super-rubbers " from which
a veritable mine of ebonite substitutes, bone substi-
C(CH)-CH» tutes, insulators, enamels, or even
| "\ hornlike artificial glasses, may in
C(CH,) — CHJx the future be manufactured, and an
industry be created in these pro-
ducts rivalling that of the coal tar dyes — an industry
which also had its origin in investigations connected
with the apparently useless products of coal tar.
Wood
I
Newspaper
Cellulose
Acetic Acetone
Acld Old method,
£90 per ton
Potatoes and Cereals
I
Starch or Sugar
Artificial Celluloid
Leather
Explosives
By two fermentation
processes
By fermentation
(old method)
Acetone
New method,
1 30 per ton
Butyl Alcohol
Fusel Oil
£30
per ton
Alcohol
I
Beverages
Amyl Alcohol
Fusel Oils
Explosives Isoprene Butadiene
I I
Rubber. Rubber.
Aldehyde
1
I
Butadiene
I
Rubber.
Chemical (Oldmethod"=ifl40 per ton)
Industries \
/
Nitro- Scents
Isoprene cellulose
Varnishes
Rubber.
Table 10.
on allowing the vulcanised product to stand in the
air it turns into a sticky mass. Perhaps in the near
future experiment may overcome this difficulty and
the substance may yet, for special purposes, attain
technical importance. Dimethylbutadiene or dipro-
pylene is obtained from acetone by reducing it to
pinacone by means of magnesium amalgam, and
then passing the pinacone over heated potassium
bisulphate, which withdraws the elements of water
from it, thus : —
Indeed, no man can foresee the consequences of
the research work now being pushed forward with
such vigour in every direction in this new field of
synthetic chemistry.
Let us hope, however, that these new industries
will remain in Great Britain and not pass, like the
coal tar dye industry, out of our hands into those of
the highly-trained scientific Germans, merely because
British manufacturers were too ignorant to employ
proper research chemists in a chemical industry, and
CH:, Utterly despised the value of science applied
to industrv. We have had a shock in this
direction, and let us hope that British manu-
facturers have now had this home truth
driven home — that Science and Industry go
hand in hand, and that pre-eminence in the
one spells pre-eminence in the other.
And now a word about the attitude of the
"Practical man" towards these new industries.
. I cannot do better than quote a few
Dr. Fritz Hofmann, of Fr. Bayer, Elberfeld, has opinions which these " practical men " have pub-
produced a whole series of similar rubbers, in which lished in trade or technical journals.
CH„ /CH,
>C:0+0:C<(
CH:,' ' CU,
2 Molecules of Acetone.
Nascent
CH,
CH,*
>C(OH)-C(OH)<
Pinacone.
KHSO,
\;h
Dimethylbutadiene Rubber. -4~
Sodii
CH,
\
/
CH,
Dimethylbutadiene.
February, 1913.
KNOWLEDGE.
45
In one important technical paper we
read to our surprise: "Naturally produced
rubber, containing as it does the greatest
elasticity with the greatest strength,
will ever hold the market "—a statement
which may be characterised as simply
untrue. Another "practical man" writes :
"I observe that twenty- five thousand
pounds of the subscribed money is to be
devoted to experimenting with the object
of producing a rubber substitute. How-
does that appeal to your readers as a
business project ? "
"It is not explained how or at what
rate the proposed money is to be ex-
pended, unless it was thought wise to
leave to the public's imagination the
rapidity with which laboratories can
dissolve gold." The gentleman is, appar-
ently, supremely unconscious that on the
basis of research work alone vast chemi-
cal firms have in Germany come into
existence which pay dividends of between
twenty and thirty per cent., and that
research work in industrial chemistry is probably
the most paying investment that it is possible to
make. On research alone some of the large German
firms spend thousands upon thousands of pounds
annually — one dye factory alone maintaining a
huge scientific library and no less than three
hundred university-trained chemists — and as a result
they dominate the world's markets!
However, the following luminous extract, gravely
printed in a financial journal, fairly reaches the
limit : —
" Is it not entirely a question of trying to make bricks with-
out straw, to try and make rubber out of rubbish ?
" People have tried to make gold and diamonds, and in these
Fennel
Synthet
Figure 44.
Mr. Harold Davies, Assistant to Professor W. H. Perkin, distilling
isoprene for making synthetic rubber.
Figure 45.
tation Vats now being erected at Rainham, Essex, by the
ic Products Company for the production of fusel oil on the
commercial scale.
cases the reward of anyone successful would be enormous.
Are they more likely to be able to make rubber, the real thing
I mean, with all the live properties in it ? As well try to make
an egg which will hatch out."
However absurd this letter appears to the trained
scientific man, it fairly accurately voices the opinions
of a great many people connected with the rubber
trade — as many personal conversations have con-
vinced me.
It is quite a common opinion that rubber is "alive "
in a way, with a special "nerve," and, therefore, like
other living matter, cannot be synthesised.
As a matter of fact, however, rubber is simply a
colloidal chemical compound or mixture of chemical
compounds, and all its properties, both
F chemical and physical, are all explicable
by ordinary chemical or physical explan-
ations without having resort to "vital
forces " or anything of a like nature.
It is only bare justice to these practical
men to say that I have not yet heard
any one of them assert that rubber has
a " soul " as well as " vital " properties.
Many other " practical " men consider
that synthetic rubber must necessarily
prove inferior to " natural " rubber
because " natural " things are always
better than "artificial" and that
" Nature " is " perfect." These indi-
viduals have evidently some character-
istics in common with the " back-to-
nature " cranks, who wish us to live in
trees and do without baths merely
because our simian ancestors had the
misfortune to be compelled to undergo
these hardships.
At the back of the minds of this
variety of "practical" men lies, no doubt,
46
KNOWLEDGE.
February, 1913.
the thought that "Nature" has in some mysterious
way a special interest, possibly of a financial
kind, in enabling plants to produce a material
good for making motor-car tyres, and that, there-
fore, the chemical compound caoutchouc, prepared
from the juices of certain tropical trees, must
necessarily be superior to the same chemical
compound prepared from petroleum or starch or
any other material of like nature. As a matter
of fact scientific botanists have unanimously come
to the conclusion that " Nature " did not have
motor-car tvres in view when she evolved these
ing material has obviously a great advantage over
Dame Nature, who has entirely different objects in
view, and there can be little doubt who will in the
long run produce the superior product for the uses
of industry.
Indeed, the prejudice against "artificial" rubber,
as such, is about as reasonable as a prejudice against
" artificial iron " or " artificial copper." The pro-
duction of iron or copper from the earthy matters
known as their ores by chemical processes is per-
fectly analogous to the production of rubber from
substances like starch or petroleum by chemical
Figure 46.
A corner in Messrs. Strange & Graham's Laboratory showing tubes of isoprene polymerising to rubber.
rubber-producing juices. She was probably trying
to perfect a means of protecting such trees against
boring insects. When a puncture was made by
an insect in the bark of a tree the sap was
exuded and the insect was overwhelmed, and so
by natural selection the highly developed rubber
trees of to-day were gradually evolved in the
forests of Brazil and of Africa. Other views of
latex formation are that the rubber is a reserve food
material for the plant, or is an excretory material
of the plant's metabolism.
The fact that the coagulated parts of the juice can
also serve to make motor-car tyres is a perfectly
accidental circumstance, which so far from being
beneficial to rubber trees may probably lead to their
extinction — of the wild varieties at any rate — if the
destruction of the rubber forests continues at its
present rate.
In fact, the synthetic chemist, who is solely
directing his energies to producing a substance suit-
able for making good motor-car tyres or waterproof-
processes ; and in the same way that the " artificial "
iron or copper of to-day is far superior to the
" natural " iron and copper, still to be found in
various parts of the world, for the purpose of making
engines or tools, so also will the " artificial " rubber
of fifty years hence be superior to the " natural "
rubber of that day for industrial purposes. Special
artificial rubbers will no doubt made be for special
purposes, just as special kinds of steel are made
to-day for special kinds of work.
That " artificial " rubber will at a blow displace
natural rubber is highly unlikely — even if the process
of manufacture is perfected. The substitution of
the one for the other will probably be a slow process,
and may never reach completion — so vast is the
demand for raw rubber and so limited are the
supplies of raw material. All that can be said
at present is that chemists have succeeded in
producing synthetic rubber, and that no scientific
reason stands in the way of them putting it on
the market.
A DETAIL IN THE PROTECTIVE COLOURATION
OF BUTTERFLIES.
(Read before the Ashmolcan Society of Oxford.)
By The Rev. F. BENNETT, M.A., Oxon.
I DO not know whether the particular detail of plete. In almost all cases the hind wing is rounded,
protective colouration to which I wish to draw while the fore wing is more or less triangular
attention has been already described in any of the in shape and ends in a point, and thus the tip
Figure 47.
Orange Tip Butterflies on WildXhervil.
Figure 48.
Bath White Butterflies.
multitudinous works dealing with that fascinating
subject ; but, if it has, I will refrain from exclaiming
with the ancient author: "May they perish who
have made our observations before us ! "
In the case of many of our English butterflies,
when one of them alights, and intends, not merely to
sun himself or display his beauties to an admiring
sweetheart, but to rest for some time, he first folds
his wings together closely back to back, and then
draws his fore wings downwards in such a manner
that they are, as completely as possible, covered by
the hind wings ; and it is obvious to any observer
that in very many cases the underside of the hind
wings is the part so coloured in various ways as to
resemble the surroundings and thus conceal the
creature from its enemies.
I say " as completely as possible " ; for the
difference in the shapes of the fore wings and hind
wings prevents this covering from being quite com-
of the fore wing remains uncovered and visible.
Now the beautiful detail which I propose to
illustrate is this: — that the uncovered portion of
the underside of the fore wing repeats in a great
number of instances the pattern and colouring of
the under surface of the hind wing and thus carries
out to perfection the concealment ; while the
remainder of the under-surface of the fore wing
covered when at rest by the hind wing, has often
quite different colouring and is in many cases of
most brilliant and conspicuous hues.
As I first observed this detail in the " Orange
Tip " (I prefer the ordinary English names to the
scientific ones, as each butterfly has such a number
of systematic synonyms), I will give that charming
little herald of spring the first place in the illustra-
tions (see Figure 47), though it is not perhaps the
best of them.
No one will, after looking at the picture, doubt for
47
48
knowledge.
February, 1913.
a moment the use of the peculiar pattern on the
underside of the hind wing. The butterfly is
settled on an umbel of wild chervil and anyone who
wants a specimen of an
Orange Tip has only to
wait in a lane full of that
plant and he will soon
find one coming along, if
it be May or June, though
he may look in vain for
one in the adjoining
fields.
The resemblance is so
complete that the butter-
fly in the midst of the
umbel can hardly be
discovered at all, and if
the photograph could
have been done in colours,
the concealment would
only have been more
completely shown ; the
white parts of the wing
representing the flowers,
and the green parts
representing the stalks,
involucres and other
green parts of the plant
as well as the background
of grass or hedge in the
distance. The conspicu-
ousness of the specimen
whose wings are not
drawn together proves
the point to perfection.
Now the pattern (we
might call it the design)
so completely conceals
the resting Orange Tip is,
it will be seen, continued
at the tip of the fore wing
and this continuation of
the pattern is precisely
outlined by the very curve
which the end of the hind
wing makes. The}' fit
exactly ! But the orange
spot is completely con-
cealed.
But there is more than
this, for it will be observed
that the front margin and
even the thin, sharp edge
of the fore wings (this
edge being often some-
what rounded) have mark-
ings of the same type, so
that, looked at ;';/ front,
the protective resem-
blance to the flower is
continued, in place of a
white line which would
otherwise appear and be
Nature's details in this m
But there is yet even
1. Large Cabbage White.
2. South European Brimstone.
3. Foreign Species.
49.
4. Small Copper.
5. Foreign Species.
6. Foreign Orange Tip.
on the hind wing which the curves fitting so truly
Figure 50.
1 & 4. Green-veined White. 6. Painted Lady.
2. Small Cabbage White. 7. Pearl-bordered Fritillary.
3. Silver-washed Fritillary. 8 &99. Grayling.
5. Orange Tip. 10. Small Heath.
dangerous — so minute are
atter.
more. It will be seen on
examination that the
pattern on the tip of the
fore wing is somewhat
run into lines (as may be
seen in Figure 50,
number 5). This repeats
a tendency to the same
thing at the margin of
the hind w ing : and it
thus imitates in connec-
tion with the background
of green, and just at the
right place, the appear-
ance which the edges of
the umbel present.
The completeness and
exactness of the continu-
ation of the pattern are
even more clearly shown
in the butterfly Figure 49,
number 6, a foreign
relative, I think, of our
Orange Tip. In this the
imitation of the pattern
on the hind wings is
much more exact, as will
be easily seen.
The economy of Nature
is wonderfully illustrated
in these cases, since there
is precisely as much of
the needed pattern on the
fore wings and no more —
— of the hind wing and of
the fore wing design.
Just the same sort of
pattern and its repetition
arc seen in the " Bath
White," Figure 48.
A brief review of the
illustrations will suffici-
ently demonstrate the use
of this arrangement of
colour and markings.
Figure 49, number 1,
and Figure 50, number 2,
show the large and small
Cabbage Whites. In
both the greenish-yellow
of the hind wing is
repeated at the tip of
the fore wing. The
colour is close to that of
the cabbage flower, but
it more closely still
resembles that of a dead
piece of cabbage leaf,
which, when faded,
takes exactly this colour.
February, 1913.
KNOWLEDGE.
49
It may be noticed that
a " small white " will
sometimes place itself
sideways, so that its
wings lie flat on the leaf.
The same is true of
"Meadow Browns," which
sometimes thus place
themselves on the ground.
Such a position would
aid in the concealment
and (in the absence of
any other explanation of
this curious custom)
would seem to be adopted
for that reason.
Figure 49, number 2,
is a South European form
of the " Brimstone " and
the greenish-yellow of the
hind wing is repeated at
the tip and along the
front margin of the fore
wing, while the folding
conceals a brilliant patch
of orange. This repe-
tition along the front
margin would be useful
while the folding of the
Figure 51. Leaf Butterfly.
fore wing behind the hind
wing was in progress, or
was incomplete.
Figure 49, number 3,
is a foreign butterfly in
which the silver spots
and olive green of the
underside of the hind
wings are repeated at the
tip of the fore wing,
whilst the rest of the fore
wing, concealed when at
rest, is of a bright red-
brick colour with black
spots, and a conspicuous
white bar.
Figure 49, number 4,
is the " Small Copper,"
in which the grey of the
hind wing is continued at
the tip of the fore wing,
and the brilliant colour
and spots hidden by the
folding over.
Figure 49, number 5 :
Underside of a foreign
butterfly. The colora-
tion of the hind wing, a
dusky brown, is repeated
Figure 52.
Marbled White Butterflies on dead panicles of grass.
Figure 53.
Leaf Butterfly, Kallima.
50
KNOWLEDGE.
February, 1913.
at the tip, and a brilliant yellow bar concealed.
Figure 50, numbers 1 and 4, are "Green-veined
whites." It is well known that these vary very much,
so that they have been divided by some authors into
several species, and the curious thing is that, as the
colours and the markings of the hind wing vary, so
precisely do the colours and marking vary at the tip
of the fore wing.
Figure 50, number 3, is the " Silver-washed
Fritillary," in which the green of the hind wings is
repeated at the tip with sometimes a little of the
silver. In other fritillaries, more or less of the same
arrangement will be found and in the "Pearl-
bordered Fritillary- " (see Figure 50, number 7),
the brick red patches which are on the hind wing,
are more or less repeated, with part of the paler
yellow at the tip of the fore wing and only
there. I do not know what this red brick may
represent, but it is evident that to have a patch of a
different colour at the tip of the fore wing would
render the creature much more conspicuous.
Figure 50, number 6, is the " Painted Lady " in
which the brown and grey of the fore wings are
repeated at the tip of the fore wing, while the
brilliant pink and yellow are concealed.
Figure 50, numbers 8 and 9, are two specimens of
the "Grayling" or " Rock-eyed Underwing." The
markings of the hind wing vary a good deal and
in exactly the same manner do the markings of the
fore wing vary to correspond, both at the tip and
along the front margin.
Figure 50, number 10, is the common little butterfly
variously called "Small Heath" and "Least Meadow
Brown." In this, when closed, the brown and grey
are repeated at the tip, while the yellow and orange
and the eye spot of the fore wing are concealed.
Figure 52 is the " Marbled White" in which the pale
and thin-lined pattern of the hind wing is repeated
at the tip of the fore wing, while the darker colouring
of the fore wing is concealed. This is more obvious
in the American form which has a brown lined
pattern on the hind wing exactly repeated at the tip
of the fore wing. I do not know what the markings
in the American species may represent, but it may
not be a wild conjecture that the object of the
pattern in the English butterfly is indicated by the
surroundings which I have given it, and that it
conceals the creature by imitating the dead panicles
of grass which abound in those dry places near
woods where the butterfly is so often to be found,
and on which it frequently settles.
We do not see the full force of any argument till
we look at it (so to speak) from the opposite side ;
and this detail in protective colouration is clearly
brought out by the cases where it is not needed.
Contrast, for example, the underside of the wings of
the " Comma," " Large Tortoise-shell," " Peacock,"
where the protective colouring is spread over the
whole of both hind wings, with the repetition of the
hind wing pattern in " Small Tortoise-shell," " Red
Admiral," and so on.
It is curious that in Anosia menippe Hiibner — a
butterfly which is now sometimes caught in England
and which is said to be protected by a nasty taste — the
paler colour of the hind wings is repeated in a patch
at the tip of the forewings, while the colour of the
rest of the fore wings resembles that on the upper
surface. The detail seems to indicate that the
bright brownish-yellow may not in these cases be
warning as had been supposed. On that supposition
it would seem difficult to find a reason (and a reason
must exist) for this curious bit of repetition.
Figures 53 & 51 are two species of the leaf butter-
flies whose likeness to dead leaves is now so familiar
to us all. These, of course, do not fold the fore wing
behind the hind wing, and there is, therefore, no
reason for any repetition of the hind wing pattern.
The tip merely displays a little imitation of a fungus.
The head of the insect is placed between the wings
and hidden, when it is at rest. This puts out of
sight the conspicuous eye, which would perhaps tell
a tale, so complete are the arrangements for conceal-
ment.
An interesting point here occurs : most dead leaves
hang down ; do the Kallimas take that position or do
the leaves of the trees on which they rest retain the
upright position when dead ? I have not seen this
noticed by the authors on the subject.
The Nyctalemon Moth of the Andaman islands
evidently represents a dead leaf, as it has an imitation
of a midrib throwing an imitation shadow on one
side, and has also a tail to represent the stalk. But
most moths appear to rely on the upper surface of
their wings for concealment. Many of them, as the
so-called " Underwings," have their brilliant colours
on the upper surface of the hind wings and conceal
these, when they are resting, with the fore wings,
which are protectively coloured. This no doubt
applies to some butterflies whose wings are coloured
in the same way.
The " Skippers " form a group half-way between
the Moths and the Butterflies. Our " Dingy
Skipper" is said to rest with the wings folded over
its back in the exact position of a noctuid. Now the
" Dingy Skipper " shows no sign of any repetition
at the tip of the fore wing of any special colour on
the hind wing : but the " Large " and the " Small "
Skippers both show the usual repetition of the hind
wing colouring. How they rest I am not certain.
Every one will, I am sure, agree that sufficient
proof has been given of the existence of this curious
and minute arrangement of Nature for the protection
of these little creatures ; but it is in all such cases to
be noticed that there is often some little imperfection
in the work of protection. It seems as if Nature in
Evolution was sometimes actuated by two or more
contradictory plans, which she has to harmonize as
best she can. There is the tendency to some pro-
tective resemblance, but there is also the tendency to
brilliance of colour or design for the purpose of
recognition by or attraction of the opposite sex ; and,
lastly, there seems to be a real tendency to develop
colour in special places, as, for example, along the
nervures of Lepidoptera, as in the " Green-veined
February, 1913.
KNOWLEDGE.
51
White," " Black-veined White," and so on, a
tendency which is also, no doubt, responsible for the
frequent coincidence of markings on both sides of
the wings, as in the " Brimstone," " Clouded
Yellow," " Apollo," and so on.
Such tendencies are obviously opposing ones ; and
one is often lost in admiration at the wonderful
methods by which Nature has reconciled them,
often producing the most perfect protection and at
the same time the greatest beauty. It is conceivable
also that in such a case as that of Danais cJirysippus
the upper side of the wings may have warning
colours while the under side, where the yellow of the
hind wings is repeated at the tip of the fore wings,
as in Anosia menippe, may be protective, to
guard against inexperienced enemies who do not
know that they are unpalatable for eating, and so
would kill or injure them in mistake, just as cats kill
innumerable shrewswhich afterwards they will not eat.
This detail in colouring shows with what minute-
ness Nature carries out the plan of protective
colouration and resemblance, and how small a piece
of detail gives some advantage in the struggle for
escape ; for otherwise this little bit of colouring
would not have continued. In further illustration
of the minuteness observe the delicate imitation of
a tear in the wing of Kallima (see Figure 53). Only
with a magnifying glass can one see that the tear is
not real, and that the wing is perfect. The effect is
produced by alternate black and white markings.
The success of the protective colouring is frequently
forced on the attention of the butterfly hunter, who
finds that the insect he has been pursuing has dis-
appeared from his view though he knows and sees,
just too late, that it has been all the while within
a very small plot of ground.
There is also another point of view which I have
not seen brought forward, as to the success of this
sort of protection. It is this : — That an animal has
no time to waste in examining objects which at closer
quarters might (though a little suspicious) turn out
to be really twigs or leaves ; and thus a very imper-
fect resemblance (to our eyes who have plenty of
leisure for the examination) would often be sufficient,
and would be preserved till in process of time a
more and more perfect resemblance was evolved. If
one watches a bird supplying its ravenous nestlings
one can easily see that it has to do the work at full
speed.
If we sometimes thus placed ourselves in the
position of animals, and by imagination " identified
our minds " (in E. A. Poe's phrase) with theirs for
awhile, we should very often comprehend Nature
better and discover more of her secrets.
CORRESPONDENCE.
A PHYSICAL PHENOMENON.
To the Editors of " Knowledge."
Sirs, — The enclosed Note on a physical phenomenon which
was observed at Maymyo towards the end of last May will, it
is believed, prove of special interest to your readers. The
author of the note is Mr. H. M. S. Mathews, C.S.I., Com-
missioner of Settlements and Land Records, Burma, and is
the outcome of his personal experience of the occurrence.
Maymyo is a hill station, the summer headquarters of the
Government of Burma. Its geographical position is 22° l' N.
and L 96° 29' E. ; and its height above mean sea level is three-
thousand seven hundred and eighty feet. The Moon was full
on 31st May at 5h 59"" 36s a.m., when its R.A. was 17° and
Dec. 27° S. ; so that the phenomenon would have been visible
when the Moon was in the E.S.E., and about 20° to 40D in
altitude.
The special points about the particular phenomenon are :
first, that the luminous area behind the shadow of the head
was accompanied by an entirely distinct circle of light some
distance away from the luminous area, the feet standing on
the circumference of this circle; second, that the phenomenon
was seen by the light of the Moon, not the Sun.
The phenomenon is believed to be what is known as Anthelia
or " Glories," the following description of which is taken
from an Encyclopedia, viz. : " Anthelia are luminous rings
seen by an observer on a cloud or fog which lies opposite to
the Sun. They are only seen when sunshine and cloud, or fog,
occur at the same time. They appear when, from an elevated
position, the shadow of an observer is projected by the Sun
on a cloud or fog ; he sees the head encircled by a glory or
luminous ring, diminishing in brightness as it leaves the head
as a centre. A phenomenon substantially similar to the
anthelia occurs when, the Sun being near the horizon, the
observer sees an aureola surrounding the shadow of his head
cast upon grass or corn moistened with dew."
Some of your readers have perhaps witnessed similar
phenomena elsewhere, and any information that they can
furnish on the subject would be very acceptable.
Rangoon (Burma).
J. C. Clancey.
Note. — On the moonlit nights of the last week of May,
1912, some days after the earthquake shock of the 23rd May,
a phenomenon, believed to be that known as Anthelia or
Glories, but novel to the observers, was seen at Maymyo.
There were heavy dews at the time and as soon as it was
sufficiently dark for the moon to cast distinct shadows the
observer noticed that on the dewy short grass of the lawn a
patch of light appeared round the shadow of the head, while
there was also an outer circle of light with the head shadow as
a centre and with a radius of the length of the observer's
shadow.
The patch of light or inner halo had no definite outline, but
was brightest alongside the shadow of the head and was
distinct over a space with about twice the diameter of the
head shadow.
The illuminated band of the outer halo averaged perhaps a
foot in width. It was narrower when the Moon was high, and
was then bright and distinct throughout its circumference.
Both halos were white, and it was noticed that the head
halo and outer halo attached to each person's shadow was
visible to that person only. Another person looking over the
first person's shoulder could not see that person's halo, though
he could at the same time see his own distinctly.
At the time of the phenomenon there appeared to be nothing
unusual in the appearance of the Moon or sky. The former
was bright and the latter clear.
The phenomenon was first noticed on Tuesday, 28th May,
and was observed for several nights. On the night of Friday,
31st May, at 10 p.m., it was seen by a number of persons and
was then very distinct.
Maymyo. H. M. S. M.
EXPERIMENTS ON LIQUID DROPS, GLOBULES,
AND COLUMNS.
By CHAS. R. DARLING, A.R.C.Sc.L, F.I.C.
I.
Before the advent of the nineteenth century, the
number of liquids available for scientific investiga-
tion was limited to water, alcohol and other products
of fermentation, naturally-occurring oils, and a few
obtained by chemical means. Now, thanks to the
advances made in organic chemistry, the number of
available liquids has been greatly increased ; but
although the' chemical properties of the newer
liquids are well known, very scanty
attention has been paid to their
physical properties. Hence the liquids
used in the ensuing experiments,
although familiar to the chemist,
would probably be designated " rare"
liquids by the physicist, because their
constants do not appear in ordi nan-
physical tables. The present articles
will be devoted to a description of
some of the remarkable physical pro-
pertiesof certain organic liquids, which
have been investigated by the writer
during the past two years, more
especially svith regard to the formation
of drops, spheres, and columns ; and
the strange movements of globules on
a water surface.
The Formation of Drops
and Spheres.
In the issue of " Knowledge "
for January, 1911, the author des-
cribed an experiment for producing
automatically large drops of aniline
under water, the process being
enable the details of formation
Figure 54.
Apparatus for forming large,
trolled drops of liquids.
sufficiently slow to
to be seen with the
naked eye. The experiment was based on the fact that
aniline is denser or less dense than water at different
temperatures, and from the standpoint of studying
the beautiful changes in shape undergone by parting
drops, suffered from the defect that the formation
was not under control. In order to produce a drop
which may be made to enlarge to considerable
dimensions, and to break at will, it is necessary to
run the liquid used into water from a vessel con-
trolled by a tap, and to employ a liquid only slightly
denser than water at the prevailing temperature.
After many trials, the author has found that the
liquid orthotoluidine is in every way suitable for
the purpose. As sold commercially, this liquid
has a deep red colour : is insoluble in water ; and at
24°C has exactly the same density as water at 24°.
Above this temperature orthotoluidine is lighter than
water, whilst below 24° it is heavier ; and as the
equi-density temperature is near to that of the
atmosphere in a room, the experiment may be con-
ducted with the minimum of trouble.
The apparatus requisite for the complete stud}- of
drops under control is extremely simple, and is
sketched in Figure 54. A funnel, furnished with a
tap, and having the stem widened at the extremity
to a diameter of three or four centimetres, is arranged
so as just to touch the surface of water contained in
a flat-sided glass vessel about fifteen
centimetres high, 12-5 centimetres
wide, and 7 ■ 5 centimetres deep —
exact dimensions being of no import-
ance. The water in the vessel should
be at a temperature of about 20°C,
and orthotoluidine allowed to flow in
slowly from the tap. A large drop
then gradually forms at the end of
the stem of the funnel, and by closing
the tap at any time the outline of
the drop may be examined at leisure.
Control ceases when the constricted
neck becomes narrow, and the drop
then slowly breaks away, a secondary
drop, as usual, being formed from the
neck itself. The accompanying
Figures — 55 to 61 — from photographs
by the writer and Mr. B. Abel, show
several stages in the formation of a
drop of orthotoluidine, controlled as
described. Figures 60 and 61 are
specially interesting as showing the
recoil after the partition of the
drop, both the portion clinging to the stem and the
separated drop being flattened ; and the secondary
drop, which is seen elongated
to have recoiled in Figure
approximately one-tenth of a
in Figure 60, is seen
61. An exposure of
second was given, the
vessel being illuminated by an arc-lamp. It is easy,
by this method, to obtain drops three or four
centimetres in diameter, if the instructions given
above be carefully followed.
An interesting modification of the
the production of inverted or rising
may be accomplished by bending
the funnel into a parallel branch,
Figure 62. The widened end is then
water at about 35°C to a depth of three inches, and
the tap of the funnel opened so as to allow the
orthotoluidine to flow slowly. As the liquid is
warmed to a higher temperature than 24°C in pass-
ing through the stem, it becomes of less density
than the surrounding water ; and on escaping the
drops, therefore, rise to the surface. The general
experiment is
drops, which
the stem of
as shown in
immersed in
52
February, 1913.
KNOWLEDGE.
53
Figure 55.
Figure 56.
Figure 57.
Figure 58.
shape of inverted drops resembles that of
falling drops, the neck, as usual, giving rise to
a secondary small drop.
The production of spheres of liquids demands
equality of density between the liquid and its
surroundings. Formerly, Plateau's method
was followed, in which spheres of oil were
formed in a mixture of alcohol and water
brought by trial to the same density as the
oil — a somewhat troublesome proceeding. By
carrying out the following instructions, spheres
of liquid, of any desired size, may easily be
obtained : — A flat-sided glass vessel, about
eighteen centimetres (seven inches) high, is
filled with water at 25°C to a height of
about twelve centimetres. The correct tem-
perature is secured by adding warm water to
tap water and mixing until a thermometer
shows 23°C. By the aid of a pipette a five
per cent, solution of common salt in water is
discharged at the bottom of the vessel, to a
depth of about two centimetres, this layer
preventing the sphere, when formed, from
sinking to the bottom when the temperature
falls. Orthotoluidine is now allowed to flow
gradually into the water from a tube of one
centimetre diameter, the end of which, to
commence with, is placed about two centi-
metres distant from the surface of the layer of
salt solution, but is afterwards raised gently as
the sphere grows in size. In this way spheres
two hundred cubic centimetres or more in
volume may be formed ; and, by raising the
delivery-tube rapidly, the attached sphere may-
be separated, and will remain floating in the
liquid.
The photographs shown in Figures 62 and
63 illustrate the mode of formation and the
appearance of the detached sphere. In the
experiment depicted the orthotoluidine was
run from a burette, with a view to measuring
the volume of the sphere, which in this case
was one hundred cubic centimetres.
Professor C. V. Boys, F.R.S., has suggested
a modification of the procedure which dispenses
with the necessity of warming the water. After
placing the layer of five per cent, salt solution
at the bottom of the vessel, the pipette is
again filled, and the salt solution discharged,
in diminishing quantities, from the bottom
layer upwards to within about two centimetres
of the surface. The orthotoluidine is then
allowed to flow into the centre of the vessel
from a tube bent so as to discharge laterally ;
and the sphere formed will then Moat or sink
until it finds a layer equal in density, in
which it will remain at rest. It is necessary, in
this case, to exercise care in grading the density
of the water from bottom to top by discharging
the salt solution slowly, and gradually rais-
Figuue 59.
Figure 60.
Figure 61.
Figures 55 to 61. Seven stages in the formation of a large drop of orthotoluidine.
54
KNOWLEDGE.
February, 1913-
ing the pipette.
It may be men-
tioned here that
certain other
liquids may be
used instead of
orthotoluidine ;
for e x a m pie ,
anisol produces
spheres when run
into water at
15°C. But the
beautiful colour
of orthotoluidine,
combined with
its insolubility- in
water, and the
absence of other
objectionable
features, renders
this liquid more
*
Figure 62. Forming a sphere of
orthotoluidine.
Figure 63. The detached sphere
floating under water.
suitable than any
other, either for
producing con-
trolled drops or
spheres. It is,
moreover, re-
latively a cheap
liquid, and should
be welcomed by
all who are in-
terested in this
fascinating
branch of physics,
as it enables
phenomena, for-
merly difficult
and troublesome
to observe, to be
demonstrated in
the simplest
manner.
COLOURS AND THEIR CHANGES AT SUNSET ON A
TROPICAL ISLAND.
By MAXWELL HALL, M.A., F.R.A.S.
Jamaican Government Meteorologist.
In connection with the researches into the constitution of the
upper regions of the atmosphere, the following notes of the
colours and their changes usually seen during the first part of
the year at the Kempshot Observatory, Jamaica, may prove
to be useful. The colours and their changes are best seen
from January to April, before the summer heat causes great
ascensional movements of vapour, and before there are many
particles of water in the air, which give rise to the gorgeous
colours seen in the autumnal months ; the steadiness of the
air throughout the nights of the early part of the year is very
remarkable, so much so that even stellar photometry is
rendered easy and pleasant work. The latitude of the obser-
vatory is 18° 25' north; the elevation is 1773 feet; the mean
temperature from January to April is 71°; the dew-point is
65° ; so that the elastic force of aqueous vapour is 0-62 inch,
and the humidity 81. The position of the observatory on a
range of hills commands a view round the horizon ; and the
hills and country round about it are clothed with thick vege-
tation, so that there is but little dust in the air. Under these
favourable circumstances notes were made which have been
condensed into the following.
Ten minutes before sunset a pink band appears on the
eastern horizon : it can usually be traced all round the
horizon ; but it soon disappears except in the eastern half,
where it grows stronger in colour and rises up from the
horizon as though on pivots at the north and south points.
Underneath it a dark band of a leaden blue colour appears.
At sunset this dark band is about li° broad; and the pink
band resting on it is about 4J° broad.
Five minutes after sunset a faint pink glow, which has
spread rapidly upwards from the pink band, reaches the
zenith. And looking above the western horizon where the
sun went down, there is a large patch of white light ; its
boundaries can hardly be defined, but they give the idea of
an equilateral triangle, whose sides are about 45°, its base
being parallel to and somewhat above the horizon. Of course,
this white light and the pink glow are easily seen by contrast
with the blue and bluish-violet of the remaining parts of the
sky.
Ten minutes after sunset the dark blue band, still resting
on the eastern horizon, is 4° or 5° broad, and is now at its
darkest; it tapers off gradually to the north and south points
of the horizon. The pink band resting upon it is now
15° broad, and similarly tapers off. The pink glow has
reached the white patch in the west, and begins to replace it.
Fifteen minutes after sunset the dark band is 63° broad,
and begins to fade away in grey colour. The pink band has
gone. The pink glow has entirely crossed over to the west,
where it is now at its strongest somewhat below the top of the
former white patch.
Twenty minutes after sunset the pink glow in the west,
having approached the horizon, disappears.
Thirty-five to forty minutes after sunset the colours of the
spectrum are best seen in the sky to the west, all parallel to
the horizon ; red on the horizon, and indigo or violet
25° above. This completes the colour-changes, the subject
matter of this article ; but the following notes are interesting
and may be added.
Fifty to sixty minutes after sunset the zodiacal light appears
about 20° or 25° above the western horizon.
Seventy-three to seventy-six- minutes after sunset, the band
of twilight along the western horizon, or the twilight arc, as it
is called, coincides more or less with the base of the zodiacal
light, which makes it necessary to discriminate between them
in ascertaining the greatest breadth of the zodiacal light near
the horizon and the greatest duration of twilight.
The angular measures referred to above were taken by a
sextant from which the telescope had been removed. The
general correctness of the whole was proved by frequently
watching the colours and their changes at sunrise, when the
whole sequence of phenomena was repeated, but, of course, in
a reverse order.
On the plains near Kingston, Jamaica, there is much dust
in the air near the ground, and the phenomena are not for the
most part so well seen ; but in the early mornings I have
there seen the dark blue band in the west as distinct or
even more distinct than at the observatory.
It would appear that the surface which reflects the faint
pink glow is about fifteen miles above the surface of the
earth ; but it would be advisable to know how far these
phenomena have been observed in other uniform climates
before attempting their explanation.
SCINTILLATIONS.
By E. MARSDEN.
Lecturer in Physics, University of Manchester.
It is well known that there are three principal types
of radiation from radioactive substances designated
a, /3 and y. The first of these types, the a rays,
or a particles, are single atoms of helium carrying
a double elementary positive charge and moving
initially with a velocity of the order 2x10" centi-
metres per second or one fifteenth the velocitv of
light. Different radioactive products emit a particles
of different speeds but the speed is characteristic
of the product. The a particles are very easily
absorbed by material substances,
the swiftest known, those from
Thorium C, being completely
absorbed by 8-6 centimetres of
air and the slowest known, those
of Uranium I, only penetrating
2-5 centimetres of air at atmos-
pheric pressure.
The second type of radiation,
the /3 rays, are known to consist
of electrons or isolated elementary negative electric
charges. They travel with enormous velocities
varying for different products, and also for the same
product, up to as much as 0-998 of the velocity of
light. The /? rays are not so easily stopped as the
a rays, travelling on the average about one metre in
air before they are stopped.
The third type of radiation, they rays, differ from
the two preceding types in that they appear to be
electrically uncharged. They are similar to very
penetrating Rontgen rays, but their exact nature
constitutes the battling ground of many rival
theorists, for the problem appears also to involve that
of the fundamental constitution of light waves.
The y rays seem to be closely connected with the
ft rays in much the same way as Rontgen rays are
connected with cathode rays. All radioactive
products which emit y rays also give /3 rays, although
certain products are known which emit $ rays with-
out any appreciable y radiation.
One of the most remarkable of the properties of the
various radiations is that of producing luminescence
in certain substances on which they fall, and more
particularly remarkable is the scintillating property of
the a rays. This property was first discovered by Sir
William Crookes, and independently by Elster and
Geitel, in 1903, but five years elapsed before its full
significance was recognised ; for it is now known that
each scintillation is produced by a single a particle
or atom of Helium. Crookes made a screen by
dusting Sidot's blende (phosphorescent crystalline
zinc sulphide) on glass. On bringing up a source of
radium the screen lit up with a greenish phosphor-
escent light which, when examined under a
s.
K
&>
K
§«
%,
P
K
Figure 64.
magnifying glass, was found to consist of a number
of scintillating points of light.
Subsequent work has shown that many other
substances show this scintillating property though
the scintillations are generally fainter than with
zinc sulphide; the best known substances being
willemite (a mineral containing zinc silicate) barium
platinocyanide and diamond. Many of these
materials appear to require the presence of some
impurity ; thus pure zinc sulphide does not show
scintillations while some of the
purest diamonds fail to respond
to any of the radium radiations.
In nearly all cases also the scin-
tillating substances appear to lose
their sensitiveness under pro-
longed action of the a rays, and
for this reason the zinc sulphide
screens of Crooke's spinthari-
scopes after a time need renewal.
Diamond and willemite are more stable than zinc
sulphide, for they retain their scintillating power
longer, while barium platinocyanide, on the other
hand, is very rapidly transformed under the action of
a rays.
It was at first thought by Becquerel and others
that the scintillations produced in zinc sulphide, for
example, are the direct result of the mechanical
fracture or cleavage of the crystals by the a particles,
since it is well known that zinc sulphide is very
sensitive to mechanical shocks. Recent evidence,
however, appears to discredit this hypothesis and
points to the conclusion that the scintillations are in
some way the result of the enormous local ionisation
produced in the zinc sulphide by the a particles ; for
it is well known that an a particle produces about
two hundred thousand ions, before its energy is
absorbed.
In 1908, Rutherford and Geiger succeeded in
detecting the emission of a single a particle by an
electrical method and were thus able to count the
a particles from a given quantity of radium. By
comparing this number with the number of scintil-
lations produced under proper conditions on a zinc
sulphide screen they were able to show that practi-
cally every u particle produces a scintillation. Thus
the scintillation method can be used for quantitative
measurements in radioactivity and this method has
since proved of very great value in such investiga-
tions ; for the electrical method of counting a par-
ticles is cumbersome and requires very special
apparatus. A piece of glass or other transparent
material is coated with small crystals of sine sulphide
and the observations are made in a dark room with a
55
56
KNOWLEDGE.
February, *913.
microscope of magnifying power in the neighbour-
hood of fifty. A good combination is a Leitz No. 0
eye-piece with a No. 4 or No. 3 objective, while it is
better to have the screen very slightly illuminated so
that the eye may be continuously focused on it.
The source is arranged so that the scintillations
appear at a rate not greater than about ninety per
minute and not less than about five per minute, these
rates being generally the limits for accurate counting.
In some cases it is necessary to have the source and
screen in a vessel at reduced pressure owing to the
limited "range" of the a particles. The scintilla-
tions are timed with a stop watch. They do not
appear regularly but are distributed according to
chance, and to obtain an accurate estimate a large
number of scintillations must be counted — in fact,
the scintillation method has given an interesting
experimental confirmation of the laws of probability
as applied to radioactive disintegration.
Perhaps one of the most interesting experiments
with scintillations is that originally used by Geiger
and Marsden in the detection of the short-lived
a ray products after thorium and actinium
emanations. Thorium emanation is a gaseous
radioactive product emitting a particles and
followed by a second a ray product whose mean life
is only one-fifth of a second, while actinium
emanation is similarly followed by an u ray product
of mean life only one three hundred and fiftieth of a
second. Figure 64 shows a " drawing room " modi-
fication of the apparatus designed by Mr. F. H.
Glew.
Sj and S2 are two zinc sulphite screens lying one
above the other and separated by thin paper strips K.K.
The upper screen is very thinly coated so that it is
practically transparent and scintillations on the lower
screen can be seen from above. M is a source of thorium
emanation consisting of a very small amount of meso-
thorium. The emanation diffuses beween the screens
in an amount regulated by the small strip P.
Consider an atom of the emanation which disinteg-
rates between the screens emitting an a particle which
produces a scintillation on either the upper or lower
screen. The atom of thorium A produced from this
emanation atom has an expectation of life of one-fifth
of a second before in its turn it disintegrates, and gives
off a second a particle which causes a scintillation on
either Sj or S2. Thus the result is two scintillations,
one following the other with about one-fifth of a
second interval. These scintillations appear on about
the same area of the screens and can be observed by
an ordinary pocket magnifying glass or microscope.
In the case of actinium emanation the scintillations
are given off with an average interval of one three
hundred and fiftieth of a second, so that the interval
cannot be distinguished by the eye, the result being
apparently two scintillations at the same time,
generally very slightly separated in position.
The scintillation method has also had an impor-
tant application in the study of the scattering of
a particles by matter. When a parallel pencil of
a particles is incident on a thin metal foil, the indi-
vidual a particles suffer deflection by the atoms with
which they come in contact and the beam as a con-
sequence becomes scattered. The distribution of
a particles in the scattered beam can be observed by
scintillations and from this distribution considerable
evidence can be drawn as to the electrical forces
inside the atoms causing the scattering. Thus it
has been shown that all atoms are constituted in some
respects similar to small models of our solar system.
They appear to have a very strong central charge
consisting of a number of elementary charges equal
to half the atomic weight. This central charge
appears to be concentrated within a volume extremely
small compared with the size of the atom and to
be surrounded by electricity of the opposite sign
which on our analogy may be compared with planets.
A PROPOSED BRITISH ECOLOGICAL SOCIETY.
The British Vegetation Committee, which was founded in
1904, has up to the present consisted only of active workers
in Plant Ecology, and has met with a very large measure of
success. In fact, it has had to be enlarged, and includes so
many " associate members " that a new Society is being formed
to take its place and push forward its work. It is felt that the
organisation of a Society with a regularly published and care-
fully edited journal might succeed also in bringing the most
scattered workers — many of whom are still outside the ranks
of the Committee — into touch with one another, and would
keep them informed of the progress of the subject. Such a
Society might also perform a similar function for the many who
are keenly interested in Ecology without themselves being
active workers in the field.
It is suggested that it should be called the British Ecological
Society, and that the annual subscription should be one
guinea, and it must be pointed out that it is intended to have
a paid Secretary and Editor, and to publish a quarterly journal
containing to begin with twelve thousand words in each
number, which would be sent post free to members, and sold
to non-members at 3s. per number.
From a circular which has been issued by the British
Vegetation Committee, and signed by Dr. W. G. Smith, of
the Glasgow and East of Scotland Agricultural College, and
Mr. A. G. Tansley, M.A., University Lecturer in Botany
Cambridge, we further learn that the Society would meet
once or twice a year in different centres, for two or three
days, and that the journal would include articles and notes on
methods, on special points of importance, reports of pro-
ceedings of the Society, with accounts of Ecological work in
progress. It would also make a feature of prompt reviews of
all important recent publications, on British vegetation as well
as foreign work which has a bearing on British Ecology.
The price of the journal and the rate of subscription to the
Society mentioned above are to be regarded as provisional ;
if sufficient promises of support are forthcoming, it will be
possible to fix the subscription at much less than a guinea.
It will be of the greatest assistance to the British Vegetation
Committee if readers of "Knowledge" who are interested
in this proposal will communicate, as soon as possible, with
the Secretary of the Committee, Dr. W. G. Smith, 9, Braidburn
Crescent Edinburgh, stating whether they are prepared to
join the proposed Society at a subscription of one guinea per
annum ; if not, whether they are willing to join at a lower rate
of subscription, stating the amount they would be willing to
pay ; and whether they have any criticisms or additional
suggestions to make with regard to the scheme proposed.
THE FACE OF THE SKY FOR MARCH.
By A. C. D. CKOMMELIN, B.A., D.Sc, F.R.A.S.
Dale.
Greenwich
Noon.
Sun.
R.A. Dec.
h. m.
22 51-1
23 9'7
23 28*1
23 46-4
o 4-7
O 22*8
7 3
5'4
3 '4
x'5
°'5
2 '5
Moon.
R.A. Dec.
h. In. o
18 51-1 S. 28'i
22 52'o S. 9-4
2 30-1 N.i8'2
7 '7'5 N.27>
12 5'I S. 0-4
16 40*1 S. 27-2
Mercury,
R.A. Dec.
h. m.
23 45-0
S.
I2'2 N.
16
2-6
5'8
7-6
v 34 '7 7 '5
o 22*5 N. 5*8
Venus.
R.A. Dec.
h. 1
I 33
N.ij-4
I5'4
■7'(
18-9
20'2
N.21'2
Jupiler.
R.A. Dei
h. m. o
18 52-0 S.22'8
18 55-5 22-7
18 588 22-6
19 I'9 22'6
19 4-7 22-5
19 7-3 S.22'4
Saturn.
R.A. Dec.
h. m.
3 45'3
3 40-6
3 48-0
3 49-6
3 51 '3
3 S3'2
N.lS'5
Neptune.
R.A. Dec.
h. m.
41-1
40-7
4°' 5
40*2
40*1
39 '9
N.20-9
20'9
20 '9
2I"0
21 "O
N.2I-0
Table 11.
Date.
Sun.
P B L
Moon.
P
Jupiter.
P B I. L T T
12 12
Saturn.
P B
Greenwich
Noon.
00 0
— 2i*9 —7*2 296'r
23-1 7'3 230-2
24-1 7-2 :64\3
24-9 7-1 98-4
25'5 6-9 32-5
— 26*0 — 6-7 326-6
0
- S'n
- 21 "o
- 17-2
+ 7'3
+ 21-9
+ IS
0 f» ° Q h. m. h. in.
— 6*j —1*9 297*0 346*6 1 43 e 10 17 e
6*3 i"9 6'o 17*5 J 59 m 1 35 /«
7*1 1 8 75-1 48*4 7 47 c 8 &e
7*4 1 '8 H4'3 79*4 8 3/// 9 48 jii
7'7 1 "8 2i3'5 no's 3 59c 8 56 m
— 8"o —1 '8 2828 141*6 4 1 5 w 6 0 e
0 0
-2'4 -24'5
2 5 z4'7
-2-6 - 24-8
Table 12.
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Jupiter Lj refers to the
equatorial zone, L2 to the temperate zone, T,, T2 are the times of passage of the two zero meridians across the centre of the
disc ; to find intermediate passages apply multiples of 9h 50im, 9h 552m respectively.
The letters m, e, stand for morning, evening. The day is taken as beginning at midnight.
The Sun continues his Northward march. It crosses the
Equator 21d 5h 18™ m, when Spring commences. Sunrise
during March changes from 6-51 to 5-42; sunset from 4-43
to 5-35. Its semi-diameter diminishes from 16' 10" to 16' 2".
Mercury is an evening star till the 27th. It is well-placed
for Northern observers. Illumination four-fifths at beginning
of month, zero on 27th. Semi-diameter increases from 3" to
Si".
Venus is an evening Star, having passed its greatest
elongation on February 12th. Illumination diminishes from
f. to J, semi-diameter increases from 15" to 23". The planet
is very favourably placed for observation by Northern
observers till the end of the month, when the crescent grows
narrow. Greatest brilliancy attained 19d 3h e.
The Moon.— New 8d 0h 22m m ; First Quarter 15d 8h 58me ;
Full 22d 11" 56mm; Last Quarter 29d~0h 58me. Apogee
Star's Name.
Magnitudes.
Disappearance.
Reappearance.
Date.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.
'9'3-
h. m.
h. in.
Mar. 12
BD+i8°347
6-9
6 281-
74°
—
— °
» 13
23 Tauri
4 3
10 5 e 61
10 58 i
282
, 13
17 Tauri
3-0
10 46 e 28
11 19 e
3'4
, 13
26 Tauri
6-6
11 8 e
IOI
—
. 13
27 Tauri
37
11 18 t;
59
0 J*m
284
, 13
28 Tauri
5-2
II 26 e
37
0 3*w
306
, 16 ...
BAC 1848
5-6
1 18 m
88
2 7 111
281
, 16
49 Aurigae
S'«
4 46 e
108
5 58'
254
, 16
51 Aurigae
5-8
7 I3«
39
7 52"
336
, 17
c Geminorum ...
5'5
7 526
142
S 52 '
252
, 23
BAC 4261
6-9
—
2 45 m
270
, 23
Spica
1-2
8 42 e 77
9 23 e
35'
, 24
BAC 4531
6 0
2 44 111 138
3 4° "'
267
, 27
BAC 5465
7 '3
— —
3 17 m
343
Table 13. Occultations of stars by the Moon visible at Greenwich.
The asterisk indicates the day following that given in the Date column.
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
Attention is called to the occultation of the Pleiades on March 13th and that of Spica on the 23rd.
57
58
KNOWLEDGE.
February, 1913.
6d 8hw, semi-diameter 14' 43" ; Perigee 21a Noon, semi-
diameter 16' 41". Maximum Librations, ld 7°N, 14d 8° E.,
16d 7° S., 27d 7°W., 28d 7° N. The letters indicate the region
of the Moon's limb brought into view by libration. E. W. are
with reference to our sky, not as they would appear to an
observer on the Moon.
Mars is a morning Star, but practically invisible.
Jupiter is still badly placed, having been in conjunction
with the Sun on December 18th. It is a morning star. Polar
semi-diameter, 16|".
March 9' 6h-7 e, 18d 7h-8 e,
Day.
West.
East.
Day.
West.
East .
Mar. 1
34
O
12
Mar. 1 7
432 '
D
1
,, 2
-.1
o
4»
,. 18
41 O
32
.. 3
3
o
'4
„ 19
(
J
A ' 1
4aJ
,, 4
I
o
324
,, 20
21 O
43
» 5
o
534
,, 21
2 O
134
., 6
2
u
34
I*
>> 22
3
J
24 •
.. 7
I
0
4
2*
>. 23
31 ©
4
,, 8
3
0
124
,, 24
32
J
14
- 9
ji
u
4
.. 25
1 O
24 3«
„ io
i
0
41
„ 26
O
1243
0
32
,. 27
21 O
43
., 12
4
o
' 3
,. 28
42 O
■3
• ,. 13
421
o
3
„ 29
43
J
2 •
,, 14
4
0
3
2*
i » 3°
43 ©
2
.. '5
43
u
12
» 31
432
J
1
„ 16
43"2
o
semi-diameter 8". The major axis of the ring is 41", the
minor axis 17". The ring is now approaching its maximum
opening and projects beyond the poles of the planet.
East elongations of Tethys (every fourth given). March
4d llh-5 w,12d 0h-9 m, 19d 2h-2 e, 27" 3h-5m. Dione (every
third given). March ld ll"-2 e, 10d 4h-3 m, 18d 9h-5 in,
26d2h-7 e.
Rhea (everv second given)
27d8h-8 e.
For Titan and Iapetus, E. W. mean East and West
elongations, I. S. Inferior and Superior Conjunction, Inferior
being to the North, Superior to the South. Titan, 3d 3h- 1 e E.,
7d 3h-7 e I., llli 0h-l e W., 15d llh-3 m S., 19d 2h-9 e E.,
23d 3h-7 e I., 27d 0h-2e W. Iapetus lld 9h-6 m W.. 31d 7h-4
e S.
Uranus is invisible, having been in conjunction with the
Sun on January 24th.
Neptune was in opposition on January 14th. Its motion
may be traced on the map of small stars which was given in
" Knowledge" for December, 1911, page 476.
Meteor Showers (from Mr. Denning's List) : —
Configurations of Jupiter's satellites at 5h m for an inverting
telescope. Table u
Satellite phenomena visible at Greenwich, 2d 5b 6m IV. Oc.
R. ; 5d 6h 9m II. Sh. I. ; 6d 4h 19m 44s I. Ec. D. ; 7d 4h 16m III.
Tr. I. ; 4h 58ra I. Tr. E. ; 5h 54m II. Oc. R. ; 13d 6h 13m 308 I.
Ec. D. ; 14d 3h 39m III. Sh. I.; 4h 38m I. Tr. I.; 5b 42m
I. Sh. E.; 15d 4h 10m I. Oc. R. ; 21d 5h 18m I. Sh. I.; 6h 0"°
46" II. Ec. D.; 23d 3h 14m II. Tr. I.; 3h 20m I. Tr. E. ;
3h 26m II. Sh. E. ; 29d 4h 29m 21" I. Ec. D. ; 30d 2h 57m I. Tr.
I.; 3h 15m II. Sh. I.; 3h 57m I. Sh. E. ; 5h 14m I. Tr. E.
All the above are in the morning hours.
The first eclipse of IV. occurs on the 18th ; the first transit
occurred February 4th.
Saturn is an evening Star, 6° South of the Pleiades. Polar
Date.
Radiant.
K.A. Dec.
Mar. 1 — 14
,, 14
„ 18
,, 24
„ 27
Mar. to May
166° + 4°N
250 + 54 N
316 + 76 N
161 + 58 N
229 + 32 N
263 + 62 N
Slow, bright.
Swift.
Slow, bright.
Swilt.
Swift, small.
Rather, swift.
Double Stars and Clusters.— The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which
two hours will overlap with the following one. Thus the
present list includes R.A. 8h to 12h, next month 10h, to 14h, and
so on. In the case of Algol variables, the time of one
minimum is given where possible, and the period. Algol,
owing to its brightness, will be given for wider limits.
Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Minimum.
h. m.
d. h.
m.
d. h. m.
Algol
3 2
+ 40° ' 6
2-310 3-4
2 20
49
Mar. 311 58 m
X Carinae
8 29
-58 "9
7810 8-6
0 12
59'6
Feb. 2 0 36 e
S Cancri
8 39
+ 19 4
8-2 to 9-8
9 n
38
Mar. 10 II 59 in
S Veloruni
9 3°
-44-8
7-8 to 9-3
5 22
24 '4
heb. 28 8 27 e
Y Leonis
9 32
+ 26 -7
9-0 to 106
1 16
28
Mar. 1 4 54;
W Urs. Maj
9 38
+ S6 '4
7-9 to 8-7
0 4
0-2
ST Urs. Maj
11 23
+ 45 '7
6- 7 to T 2
8 19
Non-Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Maximum.
V Cancri ...
T Lyncis
Z Cancri
S Hydrae
Y Draconis
R Leonis
Z Leonis
h. m.
8 17
8 17
8 18
8 49
9 32
9 43
9 47
+ i7°-5
+ 33 '8
+ 15 '3
+ 3'4
+ 78 '3
+ 11 -8
+ 27 -3
7-1 to 128
8-c to 112
8-5 to 9-2
7-5 to 12-2
8'2 to II
5-0 to IO'2
7 '9 to 96
d.
272
91
74
256
336
3:3
59
Feb. 7. Nov. 6.
Mar. 23.
Mar. 29.
Apr. I.
Feb. 23.
Feb. 9.
Apr. 6.
Table 15.
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
PHOTOGRAPHY OF THE MILKY WAY. — Mr.
d'Esterre's results should be an encouragement to the
possessors of small photographic apparatus. He has selected
a limited region of the Milky Way, near the great Perseus
cluster, and keeps a constant photographic patrol upon it with
a six and a half-inch Voigtlander camera and some smaller
instruments, also occasional visual observation with a fifteen-
inch reflector. His zeal has been rewarded by the discovery
of a faint Nova (87, 1911), which is interesting as being one
component of a double star ; also several variables. Observa-
tions of these are contained in Astronomische Nachrichten,
No. 4623, with diagrams of the fields.
It is likely that observers who selected other regions, and
followed them with the same pertinacity, would reap similar
harvests.
ATTRACTION OF SUNSPOTS FOR PRO-
MINENCES.— The Astrophysical Journal for November
contains an interesting article by Mr. F. Slocum on the large
sunspot of October, 1910, illustrated by several spectro-
heliograms in calcium light. The prominences round the
spot appear to have been strongly attracted by it, and were
seen in successive photographs to approach it with accelerated
motion. Professor Hale and Mr. Evershed had previously
noticed that the gases round sunspots were moving inwards,
but their observations indicated that the inward motion was
retarded, not accelerated. It was formerly debated whether
sunspots were formed by inrushes or outrushes of gas. The
new observations would seem to favour the former, but it must
be remembered that an inrush at one level may be accom-
panied by an outrush at another. I remember being in a boat
on the Thames immediately over the outrush of water from a
lock-sluice; contrary to expectation a counter current carried
our boat violently against the lock gate. Any violent current
generally produces a backwash. In fact, Mr. Slocum finds
evidence of such outward motion on a few of the plates, but
it is less marked and less persistent than the inward motion.
NOVA GEMINORUM (2).— The same number of The
Astrophysical Journal contains an interesting article by
Walter S. Adams and Arnold Kohlschutter on the spectrum of
this Nova. Photographic spectra on dates ranging from 1912,
March 22nd to August 19th, are reproduced, and the spectrum
of a Wolf-Rayet star is given for comparison with the last.
It has some points of resemblance, but great difference in
relative intensities of lines. The authors sum up the changes
in the Nova's spectrum thus: —
(1) The continuous spectrum got steadily weaker.
(2) An increase in the number and intensity of the nebular
lines. The chief nebular line, X 5007, was first seen
on April 6th, and afterwards became very strong.
The second line, X 4959, was first seen on April 22nd,
and rapidly grew stronger. The nebular lines at
X 4364, 4687 also got strong in the later photographs.
Using the narrowest and best-defined lines to find the
radial velocity of the Nova, they deduce a recession from the
Sun of ten kilometres per second, close to the mean of the
values nine kilometres, twelve kilometres, and seven kilo-
metres found by Curtiss, Plaskett, and Kiistner. They do
not consider that variation in the velocity is established,
though it is not impossible.
They find no evidence of the presence of radium in the
Nova, which other observers had suspected.
SIGNS OF REVIVING SOLAR ACTIVITY.— It is well-
known that the last sunspot cycle was abnormal : the maximum
was delayed three or four years after the time deduced from
the eleven year period. There was also a double maximum.
It is therefore difficult to predict for the coming cycle, but we
may anticipate a revival in the near future. One sign of the
beginning of a new cycle is the outbreak of spots in higher
solar latitudes. Mr. Maunder noted at the December Meeting
of the British Astronomical Association that a spot had
appeared in relatively high latitude, which might be the
harbinger of the new cycle. Professor Schuster expects a
distinct awakening of activity about next May. This is based
on his four-year cycle of activity, whose reality is questioned
by some students of the Sun. In any case we are probably
near the beginning of the new cycle, and a careful watch
should be kept on the Sun.
SOLAR ECLIPSES. — Our sympathies must be extended
to the numerous astronomers who visited Brazil last October
for the solar eclipse. Heavy rain prevented any results. An
interesting account of the English expedition is given by
Mr. Eddington in the January number of The Observatory.
The eclipse was an unusually dark one, and the descent of the
darkness and return of the light were both sudden.
There will be an important total eclipse in August, 1914,
the central line crossing Norway, Sweden and Russia. The
official British expedition proposes to go to the Crimea, but
there are so many accessible points on the line that the
parties are likely to be widely distributed. The British
Astronomical Association will probably organise an expedition
to Norway. If it prove as great a social success as that of
1896, and is favoured by kindlier skies, no one is likely to
regret taking part in it.
BOTANY
By Professor F. Cavers, D.Sc, F.L.S.
.BIOLOGY OF DESERT PLANTS.— Dr. D. T. Macdougal,
Director of the botanical research department in the Carnegie
Institution at Washington, has recently published (Ann. Bot.,
Vol. XXVI) a further memoir on the " water-balance " of
desert plants. The water-conducting tissues of flowering
plants are closely connected with distensible tracts of tissue
(e.g., cortex and pith) which have an appreciable capacity for
the retention of water in plants of even the most sparing habit
and structure. As the ascending water-current passes from
the root-hairs to the leaves, some of it may go into such
masses of tissue forming reservoirs in the roots, stems, or
leaves ; this accumulated supply may be drawn out to the
transpiring cells when the pressure of the solution in the cell-
sap is overcome. All plants with massive stems may thus
carry a large balance of water, and this stored solution may
play an important part in the plant's life. The relatively
largest balances are borne by some of the species characteristic
of the arid regions of the south-western and southern parts of
North America, some parts of South America, and the southern
parts of Africa ; while North Africa, Asia, Australia, and arid
regions in high latitudes everywhere have but few plants with
a large water-balance. The present paper deals with observa-
tions made in the Tucson region of Arizona, which has a
winter rainy season and a wet midsummer, with a hot dry
fore-summer and arid after-summer. The total average annual
rainfall is about twelve inches only ; the extremest arid effects
are seen in June and July, when the humidity falls as low as
six per cent, with midday temperatures of 110° F.
In desert regions the vegetation includes a number of
rapidly-maturing forms, which carry out their entire life
cycle during regular or irregular periods of rainfall, and
which are physiologically mesophytes — plants without any
marked adaptations for checking transpiration ; other forms
59
60
KNOWLEDGE.
February, 1913.
requiring much moisture occur along streams. Apart from
these, the specialised forms which are more or less active
during the dry seasons comprise two types — the sclerophyllous
and the succulent.
The sclerophyllous type iucludes a large number of woody
and spiny herbs and shrubs with reduced branches, restricted
foliage, and hardened surfaces. These xerophytes have a
very small water-balance, and the cell-sap often shows great
concentration — sometimes over one hundred atmospheres of
osmotic pressure. The specialisations shown by sclerophyllous
forms are of a direct physiological character, and entail the
least change in habit and structure.
The succulents show most of the external features of the
spinose xerophytes, which may be carried to extreme limits,
as in the Cacti where the entire shoot may be reduced to a
short cylindrical or globose form, while there is great increase
in the extent of the pith and cortex enabling the plant to carry
a large water-balance. The cell-sap of succulents usually
shows a comparatively low osmotic pressure — rarely more
than about ten atmospheres, though it may increase greatly
with desiccation.
The author describes experiments in which various plants
were subjected to desiccation, and the effects of depletion of
the water-balance noted. The large tree Cactus iCarncgiea
gigantea) may survive for a year or even more without
receiving additional water from the soil, but flowers are not
formed in the arid fore-summer unless the plant has received
its supply of water during the previous winter rainy season,
nor would apical growth ensue in midsummer unless the
summer rains were available. In Echinocactus both root
development and apical growth of the stem, with some
capacity for flower formation as well, were shown after one or
even two years of depletion of the water-balance ; individuals
exposed to the full intensity of the Arizona sunlight might not
survive for more than a year, though even the slightest
amount of shade would greatly enhance the value of the
enormous water-balance ; plants in an ordinary room were
in good condition after three years of deprivation of water. The
flattened Opuntias may exist for two or three years without a
water-supply, and may carry out seed-formation during this
period ; new joints may be formed, but usually at the expense
of the older ones, which are destroyed during the process.
In most of the plants experimented with, no notable changes
in structure were shown as the result of depletion of the
water-balance, except that the new organs formed were
usually of minimum size. The stems of Dioscorea, how-
ever, showed changes tending to the sclerophyllous habit.
Five possible causes are suggested as influencing the rate
of water-loss by transpiration in a succulent exposed to desic-
cation. (1) The increased concentration of the sap, which in
the experiments was such as to increase osmotic pressures
from four or five to ten or twelve atmospheres, might retard
evaporation from the cell-membranes. (2) A diminution of
the degree of succulence, or proportion of water per unit area
of surface present, might lessen transpiration. (3) Desicca-
tion may result in alterations in the character of the outer
membranes or of any of the transpiring cell-walls of the
plant. (4) Desiccation may stimulate the formation of new
tissues or the alteration of existing cells in such a manner as
to close openings through which water-vapour might pass.
(5) The positions of the surfaces might be shifted in such
manner as to vary the exposure and lessen transpiration.
With regard to (1), however, Livingston has shown that
concentration of the sap, even if carried to a point where an
osmotic pressure of one hundred atmospheres was attained,
would not result in a retardation of more than ten per cent,
in the rate of evaporation from a free water-surface ; hence
this factor is negligible in the present case, as the increases
found were not more than five or six atmospheres.
RESISTANCE OF PLANTS TO FREEZING.— In the
New Phytologist, Vol. VIII (1909), under the title "Vegeta-
tion and Frost," Dr. F. F. Blackman gave an interesting
summary of this subject, drawn from the researches of Miiller,
Molisch, Mez, Gorke, and Lidforss. Miiller and Molisch held
that the fatal effect of freezing upon plant-cells is due to the
withdrawal of water from the protoplasm ; but the work of
Mez went against this view. Gorke investigated the changes
in composition produced by freezing either entire plants or
their pressed-out sap, and showed that when water was with-
drawn from the cell by freezing, the salts present became
more concentrated and eventually caused the precipitation of
the soluble proteins of the cell. Lidforss found that " winter-
green " plants — delicate herbaceous plants which still bear
green leaves in mid-winter, though showing no obvious
structural adaptation for protection against cold — contain
quantities of sugar in winter, this being replaced in summer
(or in winter if the plants are brought into a warm room) by
starch ; and his observations strongly support the view that
the presence of sugar retards the "salting-out" or precipitation
of the proteins, which Gorke had described.
The chemical means of protection of plants against freezing
have recently been investigated by Maximow (Ber. deutsch.
bot. Ges., 1912). He finds that the introduction of neutral
organic substances, such as carbohydrates, alcohols, and
acetone, into the cells of plants increases their power of
resisting cold, in the case of tropical plants as well as those
of temperate climates. The protective action of such sub-
stances does not stand in direct relation to the osmotic
pressure and the lowering of the freezing-point — as the con-
centration of the substance rises, the resistance to cold
increases at a more rapid rate than the lowering of the freezing
temperature. Different substances differ in their effect, and
of the substances tried the sugars have the greatest effect ;
then come glycerine, the alcohols and acetone. On the with-
drawal from the cells of the protective substance which has
been artificially introduced into them, the power of cold-
resistance returns to its original condition ; and when " winter-
green " and other plants are placed for some time in water,
their cold-resisting capacity is diminished.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon), F.I.C.
THE MANUFACTURE OF SUGAR FROM SAW-
DUST.— In a recent issue of the Journ. Roy. Soc. Arts
(1912, LXI, 69) there is an interesting outline by Mr. A.
Zimmermann, of the manufacture and utilisation of the sugar
produced by hydrolysing sawdust with an acid. The methods
employed in obtaining alcohol from woody fibre have already-
been described in these columns and the Classen process used
in the production of the new commercial product " sacchu-
lose " is based upon similar principles. The sawdust is
treated with a solution of sulphurous acid in a closed vessel
under a pressure of ninety to one hundred pounds per square
inch, with the result that a product containing about twenty-
five per cent, of sugars and a porous friable residue of modified
wood fibre is obtained.
Owing to the changes in the physical and chemical structure
of the material the crude product will readily oxidise on
exposure to the air, and to obviate this the " sacchulose " is
mixed immediately after its formation with a certain propor-
tion of molasses or fatty matter, with the object of preventing
the air from coming into contact with the sugars.
Experiments upon the use of the mixture as a feeding stuff for
animals have given very good results. The trials were made
upon working horses and extended over a period of six
months, four lbs. of the oats in their former daily rations
being replaced by four lbs. of the prepared " sacchulose."
At first the animals lost in weight, but after they had become
accustomed to the change, increases in weight of thirty to
eighty lbs. were recorded.
Eighty per cent, of the sugars are fermentable and the
original idea of the manufacturers was to produce a cheap
commercial spirit which might possibly be used as a fuel for
motors. The spirit obtained by fermentation and distillation
of the soluble sugars is of excellent quality, and acetic acid,
February, 1913.
KNOWLEDGE.
61
methyl alcohol and furfural could be obtained as by-products
from the residue. A yield of thirty to thirty-five gallons of
proof spirit would be obtainable from each ton of sawdust,
and on this basis it is calculated that in a factory where two
hundred tons a week were treated, the yearly output of spirit
would be from three hundred thousand to four hundred
thousand gallons. Unfortunately for the development of
this side of the scheme, the restrictions of the Spirit Act of
1880 bar the way, and fresh legislation is required before
anything can be done in this direction.
FABRICS OPAQUE TO X-RAYS.— It has long been
known that silk can be loaded with various metallic salts, and
advantage is taken of the fact in commerce to sell silk which
is sometimes weighted with as much as one hundred and fifty
per cent, of a tin salt. A more legitimate use of this absorptive
power of silk is described in the Comptes Rendus (1912,
CLV, 706) by M. L. Droit, who has found that by using
certain lead salts for the weighting, a silk fabric may be
rendered opaque to the passage of X-Rays. For example, a
material thus prepared by treatment of the silk with lead
phosphotannate and other salts contained sixty-eight percent,
of mineral matter, including thirty-four per cent, of lead oxide,
twenty-four per cent, of tin oxide, eight per cent, of phosphoric
anhydride, and two per cent, of lime and alkalies. Slight
discharges, of X-Rays were practically arrested by two layers
of this fabric, while six layers were found a sufficient protection
to the skin against the action of an ordinary discharge of
medium strength. This fabric had the same protective effect
as a sheet of copper 0-044 millimetres in thickness, and had
the great advantage of flexibility, even when used in a thickness
of several layers.
THE ODOUR OF CLAYS.— An investigation of the
cause of the well-known characteristic odour of certain clays
has been made by Dr. P. Rohland (Zeit. physiol. Chem.,
1912, LXXXI, 200). The peculiar odour which may be
imparted to other substances either of a colloidal or crystal-
loidal character, is rendered more perceptible by moistening
the clay with water or alkali solution, especially in the case of
kaolin clay. It is suggested that in the formation of such
clays during the weathering of granitic rocks, bacteria or
other micro-organisms may have had a share in the disinte-
gration and that the odour may be due to the presence of their
dead cells. In support of this view it is pointed out, that
organic matter is frequently present in kaolin clay, and plays
a part in rendering it plastic. If the clay has been purified
by sedimentation in water so that the organic colloidal sub-
stances have been removed, it ceases to be plastic. Kaolins
rich in such organic matter are not only very plastic, but also
possess the property of taking up other colloids to form loose
absorption compounds. When kaolin clay is digested with a
mixture of water and an aromatic hydrocarbon, such as
benzene, it becomes quite impervious to the hydrocarbon,
though it will still allow the water to pass.
COMPOSITION OF THORIANITE.— An examination of
various specimens of the mineral thorianite has been made
by Mr. M. Kobayashi (Science Reports, Tohoku University,
Japan, 1912, I, 201), who concludes that there are two
varieties, one of which contains about seventy-eight per cent
of thorium oxide, and about fifteen per cent, of uranium oxide,
while the other contains about sixty per cent, of thorium oxide
and thirty-three per cent, of uranium oxide. In the first of
these varieties the rates of ThO-2 to UO2 would thus be as
6:1, while in the second the ratio would be as 2 : 1. The
remarkable discrepancies in analyses, previously published, of
the composition of this mineral are readily explained on the
assumption that the materials examined consisted of mixtures
in vaiying proportions of the two varieties.
Some years ago a specimen of thorianite from Ceylon was
described by Messrs. Dunstan and Jones (Proc. Roy. Soc,
1906, LXXVII A, 546). This was very rich in uranium, and
the proportion between the two oxides was taken to indicate
that the uranium and thorium oxides were present in
thorianite as isomorphous mixtures and were not in chemical
combination. Mr. Kobayashi is opposed to this view on the
grounds that the molecular ratios mentioned above could
scarcely be accidental, and that while ignited thorium oxide is
nearly insoluble in nitric acid, thorianite is fairly soluble even
after ignition.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
THE SUSSEX SKULL. — A most important discovery of
human fossil remains has been made by Mr. Charles Dawson
in a gravel-pit near Piltdown Common, Fletching, Sussex, and
described at a recent meeting of the Geological Society. The
section, about four feet thick, consists mainly of water-worn
fragments of Wealden ironstone and sandstone, with occasional
chert pebbles, and a considerable proportion of water-worn
flints. In addition to a portion of a human skull which was
found by workmen, Mr. Dawson obtained half a human man.-
dible, broken pieces of the molar of a Pliocene type of
elephant, a rolled cusp of a molar of Mastodon, and teeth of
Hippopotamus, Castor, and Eqnus, with a fragment of an
antler of Cervus elaphus. All these fossils, including the
human, were well mineralised with oxide of iron. Many of
the iron-stained flints resemble the "eoliths" from near
Ightham, and with them were obtained a few Palaeolithic
implements of Chellean type.
The Piltdown gravel is eighty feet above the river Ouse,
and less than a mile to the north of the existing stream. The
authors believe that the gravel is of the same age as the
contained Chellean implements. The various teeth are
believed to have been derived from older gravels ; but the
human skull and mandible, which do not show signs of water-
transportation, are assigned to the period of the deposition of
the gravel. The remoteness of this period is indicated by the
fact that the Ouse has since deepened its valley by eighty feet.
The human remains were described by Dr. A. S. Wood-
ward, who suggests that they belonged to a female individual,
and represent a hitherto unknown genus and species. In an
appendix, Professor Elliot Smith remarks that although the
brain shows a general similarity to the cranial casts of
Palaeolithic man, especially those of Gibraltar and La Quina,
it is smaller and more primitive in form than any of these. A
most noteworthy feature is a pronounced gorilla-like drooping
of the temporal region, indicating feeble development of that
part of the brain which is known to be related to the power of
speech. Dr. Woodward concluded that the jaw was simian in
type, although found in association with a human type of
skull, and in this he was supported by Professor Elliot Smith
and Sir E. Ray Lankester. In the discussion Professor
Keith thought that the simian character of the jaw and the
primitive characters of the skull were incompatible with
Chellean age. In his opinion the skull was of the same age
as the mammalian remains which were admittedly Pliocene.
Hence he believed that Tertiary man had been discovered in
Sussex. Mr. Clement Reid was of the opinion that the
Piltdown deposit, and the plateau on which it rests, belong to
a base-level plain which originated about the period of
the Brighton raised beach. The deposit was not Pre-Glacial
or even early Pleistocene, but occurred at the very base of the
great implement-bearing succession of Palaeolithic deposits in
the south-east of England, and belonged to an epoch long
after the first cold period had passed away.
THE MOINE GNEISS.— The new geological Survey
Memoir bearing the cumbrous title, " The Geology of Ben
Wyvis, Cam Chuinneag, Inchbae, and the Surrounding
Country," is a most interesting production, and students of
the petrology of the metamorphic rocks will find in it an
excellent discussion, by Dr. J. S. Flett, of the Moine and
other gneisses and schists in this area. The Memoir describes
an area of four hundred and thirty-two square miles, almost
all of which lies in Ross-shire and extends westward from
the Cromarty and Dornoch Firths. A few small inliers of
Lewisian gneiss occur in the south-west, but the major part
62
KNOWLEDGE.
February, 1913.
Figure
of the district is occupied by the Moine gneisses, which are
paragneisses representing a great sedimentary series originally
composed of sandstones, pebbly grits, and sandy shales. The
Moine is divided into four groups, of which the one supposed
to be the highest in stratigraphical sequence is pelitic or semi-
pelitic in composition, and is
invaded by a great mass of
foliated granite (augen-gneiss),
with subordinate basic and
alkaline varieties. All the latter
were intruded into the Moine
sediments prior to the move-
ments which transformed the
rocks into gneisses. This is
shown by the fact that the Carn
Chuinneag granite has still
preserved around it an aureole
of contact - metamorphism
which has resulted in the pro-
duction of hard, fine-grained
hornfels from the original
sandy shalesof the Moine. The
induration of the hornfels has
been such that, in many places, they have completely resisted the
gneiss-making movements,and are in substantially thesamecon-
dition as when first formed. Although completely recrystal-
lized these hornfels have never been deformed or sheared, and
have preserved a fine sedimentary lamination. Even sun-
c racks and ripple-marks have been observed on the surfaces
of the bedding planes. They,
therefore, prove up to the
hilt the original sedimentary
character of the great series
of Moine gneisses which
occupy so much of the
North of Scotland.
MICROSCOPY.
By F.R.M.S.
A "DOMESTIC" FUN-
GUS.— Owing to the very
wet autumn a damp spot
appeared on the ceiling of a
bedroom, and in a short time
a small fungus developed on
it. It is a species not in-
frequent under similar cir-
cumstances, though probably
seldom identified. It begins
as a cottony web-like my-
celium, very delicate and
invisible on the white of the
ceiling, the threads composing
it being without colour. On
this arise minute, almost
spherical, bodies, the micro-
scope showing them to consist
of fine filaments arranged side
by side. As growth proceeds,
these spread at the top,
forming somewhat cup shaped
objects, but commonly much
distorted by pressure as they
usually occur close together
in patches. Inside they are
packed with parapliyses, long
hair-like objects, and asci (plural of ascus) narrow sacs, each
containing at maturity eight oval thin-walled sporidia, arranged
in one row ; when ripe they measure from sixteen to eighteen
/* long, by about eight ^ wide, and are then ejected by means
of any change of temperature or moisture. The little fungi
are usually pale salmon pink, but sometimes are white, though
apparently differing in no other way. This species is named
Peziza domestica, as it is most commonly found on damp
ceilings and the plaster of walls in houses, but it occasionally
Peziza domestica.
b
L
\
V 7
Figure 66. Natal Psychidae (natural size).
arises also on burnt ground. There are some hundreds of
species of the genus Peziza, which are in most cases elegant
little cups often very minute, and grow on various objects out
of doors, such as twigs, leaves, and other refuse, particularly
of a vegetable character. This example is not a very typical
one, as the body of it is
scarcely cup - shaped, but
rather sub-cylindrical with a
conical base, and shows no
hollow. It is small, measuring
only about • 5 millimetres in
diameter and frequently much
less. The Pezizas are members
of the Discomycetes, a very
large group of the Ascomy-
cetes, which are so named
because, as in this case, the
spores are formed in an
ascus. The spores are called
sporidia as a distinction
from those arising without this
organ. In Figure 65, A shows a
young and mature specimen
seated on the mycelium ; above is sketched a surface view
showing the irregular form caused by crowding. At B is a
sectional view of the fungus on a larger scale, showing the
asci with sporidia in various stages of growth, among the
numerous paraphyses ; above is some of the web - like
mycelium ; and at c an ascus with sporidia, two paraphyses
and two free sporidia, all
more highly magnified.
Jas. Burton.
PSYCHIDAE.— The cat-
erpillars of the Psychidae
are amongst the most curious
and wonderful to be found
in the insect world, since they
make and live in houses of
marvellous construction which
they carry about with them
wherever they go. These
houses differ in shape and
material in different species,
and though our British ex-
amples are small and incon-
spicuous, some of those
found in South Africa and
India reach a length of over
three inches. Our illustration
gives a selection of typical
forms from Natal, drawn
natural size. Of these, Figure
66a shows a caterpillar with
its head and first three seg-
ments protruding from its
house, the rest of the body
remaining inside. In this
manner it walks about and
feeds, always dragging its
house with it, which in this
instance is formed externally
of small sticks cut into short
lengths symmetrically arrang-
ed and fastened together
with silken threads. The
inside is lined with a smooth
blanket of silk, quite closed at one end, but having a door at
the other end constructed of a number of stiff pieces of dried
grass fastened round the edge of the blanket and attached to
it in such a manner that when the occupant retires within, it
can close them down and cause them to interlace so effectually
that not even the smallest of insect enemies could gain admit-
tance. When night approaches the caterpillar suspends its
house from the branch of a tree by a silken cord, and then, re-
treating inside, closes the door and snugly reposes in its blanket
l
1
;
February, 1913.
KNOWLEDGE.
63
until the morning. Some which I kept alive in a box, found at
first some difficulty in thus suspending themselves from the glass
cover, but this was at length overcome by making a lattice-
work path of silk across the underside of the glass along
which they were able to walk and from which they hung their
houses every evening. A number of eggs laid by the moth
of one species on the flowers of one of the Compositae
hatched out as the flowers were maturing, and the larvae, one
thirtieth of an inch in length, immediately began to cut up
the feathery pappus and constructed the most perfect little
houses, which they somehow managed to enlarge as required
by their growth, without alteration of the original design. In
Figure 66b, the house is made of pieces of the stems of fine
grass arranged in parallel lines. Figure 66c is apparently
made of some kind of fibre worked together obliquely and
partly covered with silk. Figure 66d is presumably made of
fine fibres but is so completely covered with silk as to prevent
them from being seen. Figure 66e is formed of two kinds of
sticks fastened together lengthwise. Figure 66f is chiefly
constructed of the dried spikelets of grass overhung with a
roofing of grass leaves. Figure 66g is obviously made of
sticks, the ends of some of which are seen projecting through
a thick covering of silk, and Figure 66h, consisting chiefly of
the small dried leaves of a Mimosa, has been cut open,
showing the chrysalis inside.
The natives of Southern India, where Psychidae similar to
Figure 66a are not uncommon, regard these creatures as the
embodiment of the souls of men who having during their
human lives been addicted to the stealing of firewood, are
passing their next period of existence attached to a bundle of
sticks. The Kaffirs of Natal, however, have given them the
common name of Mahambanendelwhana, which, being trans-
lated, means " he that goes with his little house." Friends
who sometimes complain of the long names given to insects
by entomologists, will possibly think that this is no improve-
ment. R, T. L.
ON THE RELATION OF APERTURE TO POWER
IN THE MICROSCOPE OBJECTIVE.— That opticians
are human they would themselves admit, and to supply what
the public demands is the essence of business with them as
with everyone else. Moreover, competition is keen, and hence
each tries to give his customers a better bargain than can
elsewhere be obtained.
Now, by a "better bargain," the microscopical customer
only too often understands objectives of higher numerical
aperture, since stands, eyepieces, and condensers of similar
quality are now much the same price everywhere. But A puts
into his a two-third inch of N.A. -30 and a one-sixth inch of -88,
B gives N.A. -28 and -74 respectively, whilst C gives -25
and • 65 for these same lenses. The one-twelfth oil immersion
is almost invariable everywhere nowadays, being of about
N.A. 1-30, and costing five pounds.
In the above case A would often get the order, the tyro
arguing that increased N.A. meant more resolution, and there-
fore better results. It is altogether forgotten that behind
everything is the human eye, and that this admits of improve-
ment within but narrow limits. Let us see what those limits
are.
The standard distance for ordinary eyesight is ten inches.
Most people can with but little practice, by the aid of a rule
divided into tenths, prick off divisions as small as the one-
hundredth part of an inch. We may take this as fairly easy.
Now let us go a step further and ask how closely can we
read a millimetre scale ? Remember a millimetre is practi-
cally one twenty-fifth of an inch. Can we without a vernier,
or lens or any other extraneous aid, read it closer than to one-
fifth of a division, i.e., one hundred and twenty-fifth of an
inch ? Very few would say that this was possible with ease,
and, above all, certainty. Rule, e.g., a few lines of different
lengths. Obtain a glass scale with millimetre divisions on the
lower surface (so as to avoid parallax) then measure the lines
and put the measurements down on paper. Ask others to do
the same, and you will find that the fifth of a millimetre is
about the average of good ordinary eyesight, and that even
if one has large powers of accommodation and can, for instance,
read ordinary print at, say, five inches distance, yet the milli-
metre scale will still defeat us if we attempt to read it closer
than fifths.
Let us go elsewhere for confirmation. Vega forms the
brightest of a small triangle of stars distant from each other
less than two degrees. The one N.E. of Vega is e Lyrae, a
noted double double. Most people cannot see it double at all.
Many astronomers can separate them without artificial aid.
Smyth says : " The naked eye sees an irregular-looking star
near Vega, which separates into two pretty wide ones under
the slightest optical aid. " So," adds Webb, " I see it, and
probably most observers," but notes that Herschel, Bessel
and " many others have divided it with the naked eye." The
distance is three minutes twenty-seven seconds. This angle
corresponds almost exactly to one hundredth of an inch at a
distance of ten inches.
Now let us return to the microscope. In Mr. Conrad Beck's
Cantor Lectures on " The Theory of the Microscope " page
40, we read, "It is generally considered that for every one
hundred magnifying power the numerical aperture should not
be less than about -2 N.A.
Now, a numerical aperture of -2 should resolve nineteen
thousand three hundred lines to the inch. With a power of
one hundred we must be able to separate lines -1ib80 = tJ3 of
an inch. This agrees well with Professor Abbe's calculations,
which are based on the assumption that the human eye can
distinguish intervals, having an angle of two minutes or jif-j at
ten inches. Mr. E. M. Nelson puts the ratio as a magnification
of one hundred to -26 N.A. Now, -26 N.A. will resolve
twenty-five thousand lines per inch. In this case, therefore,
we get the limit of resolution of the eye itself given as two
hundred and fifty lines per inch. Professor Abbe's researches
date from 1874-5 ; Mr. Nelson's opinion dates from 1883 ;
whilst Mr. Conrad Beck's lectures were given in December,
1907.
We may approach the solution of the question by asking at
the very commencement what eyepiece magnification and what
tube length must we predicate ? As regards the latter we have
no choice, the six-inch tube (one hundred and sixty milli-
metres) being now almost universal. Eyepieces, too, are now
almost universally the same and give, with the one hundred
and sixty millimetres tube, powers of 3, 4, 5-5, 7, and 9.
Professor Abbe gives the upper limit of eyepieces as ten with
N.A. -10 and only four with N.A. -90. His researches, as I
have just said, date from 1874 when the substage illumination,
at least on the Continent, was of the most primitive descrip-
tion. At the present day, whilst the experienced worker con-
fines himself as far as possible to low and medium eyepieces,
he does not hesitate to use the higher if required to reveal
structure. Much, however, depends on his objectives.
Passing over the lower power lenses, which are used only as
finders, we come to those useful medium powers ranging from
the one-inch to the half-inch or four-tenths of an inch, which
consist usually of two doublets.
These admit abundance of light and often possess a work-
ing distance equal to three-quarters of their focal length.
They can scarcely be said to be used for highly critical
work and will bear an eyepiece magnification of at any
rate more than ten. Professor Abbe gives such moderate
powers an eyepiece amplification of 5-5 to 9 and since his
day the excellence of objectives has advanced all along the
line thanks to the Abbe-Schott glass and other causes, so that
nowadays every objective of four-tenths of an inch or lower
will bear an eyepiece magnifying ten on the one hundred and
sixty millimetres tube. Even then we must be careful as to
the illumination or we shall only get a foggy glare.
Dry objectives of high power ranging from, say, one-quarter
of an inch to one-tenth of an inch now almost invariably con-
sist of a hemispherical front with two correcting systems of
lenses behind. It is not easy to make such a combination
much lower than -60 N.A. and they range as a general rule
from -60 to -90 N.A. It is with these that the greatest
improvement of all has taken place. The new optical glass,
and especially the use of fluorite in one of the back combina-
tions, have led to such an advance in the colour corrections
of these series that nowadays one can often scarcely see the
64
KNOWLEDGE.
February, 1913.
difference between them and the apochromatic, so incon-
spicuous is the secondary spectrum. For photographic work,
with the monochromatic screen, they are equally as useful as
the much higher-priced lenses. Their spherical correction is
excellent, at any rate up to nearly -90 N.A. We, however,
begin to note a falling-off in the quality of the image under
the higher eyepieces, though nearly all stand an eyepiece of
X 10 with little or no deterioration. It may be said that
photographs show that such powers will give good definition
up to nearly fifteen times their initial power. But in photo-
graphy there are no muscae to disturb the sight, and the effect
is. above all, cumulative. Even for photography this limit is
never exceeded, except for well-marked objects like such
diatoms as are well within the resolving power of the objective.
We may, therefore, take it that one hundred and twenty-five
lines to the inch is about the average power of resolution for
the ordinary eyesight, and that an eyepiece magnification of
ten can be used with any objective of the present day con-
sistently with perfect definition and sufficiency of light.
We must now endeavour to find out the initial power of the
objective suitable for each numerical aperture. This is fairly
obvious.
An objective of • 13 N.A. will resolve twelve thousand five hun-
dred lines to the inch according to the well-known tables of the
Royal Microscopical Society, the accuracy of which have never
been impugned. To accomplish this the objective must have an
initial power of ten which, multipled by ten (the power of the
eyepiece), and then by one hundred and twenty-five (the limit
of resolution of ordinary eyesight), gives us the twelve thousand
five hundred required.
Now an objective with an initial power of ten must be of
sixteen millimetres focus, i.e., two-thirds of an inch. Thus, a
sixteen-millimetre objective should possess an aperture of -13.
The lowest usually made at the present day is -20 N.A., so
that it has a large surplus of aperture, and would resolve
nineteen thousand two hundred and eighty-two lines to the
inch with an eyepiece magnifying 15-4 times. As a matter of
fact, it is easier to make a sixteen-millimetre objective of the
higher N.A. than as low as -13 N.A., which latter could only
be done easily by using a single achromatic triplet which would
not bear an eyepiece of more than X 7.
We may now construct a table of magnifications of the
corresponding N.A., and of the focus of the objective required
to obtain that magnification with an eyepiece amplification of
X10.
Focal length of
Magnification. N.A. Objective.
100 -13 16-0 mm.
200 -26 8-0 „
300 -39 5-33 „
400 -52 4-0 „
500 -65 3-2 „
600 -78 2-67 „
700 -91 2-3 „
The point to be observed is that the above are the minimum
figures really required. As we have said, it is not easy to make
objectives of as low a numerical aperture as the first five,
owing to optical difficulties. Nor would an addition of
reasonable amount be objectionable, so long as proper working
distance be kept in view. It is, however, useless to give us a
four-millimetre (one-sixth) objective of N.A. • 88, as its aperture
could not be fully utilized except by employing such high
power eyepieces or lengthening the tube as would utterly break
down the critical character of the image. Anything above
• 52 N.A. for such an objective is of little or no value, and if
working distance is sacrificed to obtain a higher aperture it is
worse than useless. As a matter of fact • 65 N.A. is the lowest
aperture in which such a lens is made. Fortunately, opticians
are beginning to see this, and we have now objectives of this
focus beautifully corrected with a working distance of one
millimetre, thus allowing them to be used with Thoma-Zeiss
Haemocytometer, or with thick covers.
It will be said that greater aperture means more light, but
in these days of efficient condensers this is no desideratum.
As a general rule, the light nowadays is oftener too much than
too little.
Besides, we sacrifice depth of focus, which is too often
confounded with working distance, but which really varies
inversely with the N.A. Thus, in two six-millimetre objectives
of -62 and -92 N.A. respectively, the former would possess a
depth of focus of 1-6, the latter that of 1 • 1 only, or one and a
half times the latter — an important point, especially in micro-
photography.
It may be added that the one-twelfth homogeneous
immersion usually sold cannot be improved upon either in
aperture or power, as will be seen if the reader will carry on
the figures in the above. It possesses a good proportion of
aperture to power and reasonable working distance, consider-
ing the aperture.
It will be asked what size would the disc of confusion be
with such low apertures ? The usual formula being employed,
100 1
we have
inch which is at any rate a safe
95000 X -13 123-5
limit above the conventional one-hundreth part of an inch.
With Mr. Conrad Beck's formula rigidly applied, we have the
following table : —
Focus of Objective
Magnification. N.A. with Eyepiece 10.
100 -20 16-0 mm.
200 -40 80 „
300 -60 5-33 „
400 -80 4-00 „
500 1-00 3-20 „
A power of four hundred and fifty would thus be the limit
for dry objectives of -90 N.A. The circle of confusion with
this series would be the one hundred and ninetieth part of an
inch.
With Mr. Nelson's formula we get : —
Focus with Eye-
Magnification. N.A. piece 10.
100 -26 16-0 mm.
200 -52 8-0 „
300 -78 5-33 „
400 1-04 4-00 „
His circle of confusion would thus be the two hundred and
forty-seventh part of an inch.
Comparison of the above with Professor Abbe's figures is
not easy, since, as we have said, he decreases the power of the
eyepiece as that of the objective increases, but no formula is
given for the relationship between the two. They are simply
the results of experiments made in 1 874 on several objectives.
Professor Abbe's paper was read on June 14th, 1882.
The following extract only from his table will suffice.
Total Magnification Magnification Focus of
N.A. magnification, of eyepiece. of objective. objective.
•10 ... 53 ... 10-0 ... 5-3 ... 47-2 mm.
•20 ... 106 ... 8-2 ... 12-8 ... 19-4 „
•30 ... 159 ... 6-7 ... 23-7 ... 10-5 „
•40 ... 212 ... 5-6 ... 37-9 ... 6-6 „
•50 ... 265 ... 5-0 . ... 53-0 ... 4-7 „
•60 ... 317 ... 4-6 ... 68-9 ... 3-6 „
•70 ... 370 ... 4-3 ... 86-0 ... 2-9 „
•80 ... 423 ... 4-1 ... 103-2 ... 2-42 „
•90 ... 476 ... 4-0 ... 119-0 ... 2-10 „
That this table does not agree with modern practice will
probably be admitted. That modern objectives will bear
higher eyepieces than the last six or seven of the table will
probably also be allowed. This, however, is no fault in the
table itself, which I cannot doubt was correct for most objec-
tives of 1874. It is due to Professor Abbe himself that we
are able to use new formulae for new objectives. The Abbe-
Schott glass it is that enables the modern optician to make a
dry one-tenth of an inch objective almost as perfect as the
inch or the two-thirds of an inch. Professor Abbe's table
shows us only the better the result of his investigations in
both the theory and practice of the construction of objectives.
Thus, we reject most of his tables as too low. We must
reject Mr. Nelson's as too high. There remain Mr. Beck's
and my own. The latter are, as I have explained, the
minimum that can be adopted with safety, and some may
prefer for a magnification of one hundred an aperture of • 15,
February, 1913.
KNOWLEDGE.
65
or even -17, but the former would be ample for even
" spotting " diatoms, giving a circle of confusion of about
the one hundred and forty-third part of an inch.
The point to be noted above all is, that for good working
distance and depth of focus the lower the angle the easier the
work. Empty amplification is a great mistake, empty aperture
is a greater, and much more expensive and equally valueless.
A four-millimetre objective, e.g., of N.A. -65 or -74, is far
more convenient than one of N.A. -90 which will only work over
No. 1 covers, whilst the former have working distances of a full
millimetre. But the craze for " angle " is still with us, and
many would rather take a quarter of an hour in coaxing a
quarter-inch to resolve Angulatum than put on a one-twelfth
inch and do it in one minute. Where, however, the
student wants efficiency, convenience and moderation in price,
he will get low angles for dry objectives based on N.A. -15
per one hundred magnification. A one-sixth inch that
will not work over any cover, even a No. 3, is a nuisance in a
laboratory, and an unnecessary nuisance, too.
Meanwhile, opticians laugh in their sleeves and play to the
gallery, and above all rake in the coin that foolish men throw
away. If their clients will spend two pounds on a two-thirds
where one pound would buy an equally useful one, or three
pounds on the one-sixth where thirty shillings might have
sufficed, they cannot complain. Meanwhile the student has
wasted two pounds ten shillings : that is, half the cost of a good
one-twelfth inch oil immersion which some day he must buy.
Let him remember that useless aperture is a useless possession.
There is also another matter which these investigations
bring out, and one which is of great practical importance,
namely, the limit of useful magnification, and on this we must
touch briefly.
At present the highest numerical aperture is 1 • 50. It will
therefore be seen that if for every one hundred of magnification
we allow a numerical aperture of -20, the highest useful power
will be seven hundred and fifty. Anything beyond that reveals
no further structure, according to Mr. Conrad Beck's formula.
With him agrees Professor Abbe. By Mr. Nelson's formula,
the limit of useful power will be only = 577, a
•26
much lower figure.
Let us now take facts. Most opticians make a two-millimetre
semi-apochromatic of N.A. 1.30 at £5, and one of N.A. 1 -40 at
a varying price. They are, of course, oil immersions. The
resolving power of the former is about one hundred and
twenty-five thousand, and of the latter, one hundred and thirty-
five thousand, as given in the tables. By photography these
limits may be extended to one hundred and sixty-five thousand
and one hundred and seventy-seven thousand eight hundred
respectively.
The test diatom, Amphipleura pellucida, varies but slightly
in its markings between ninety-five thousand and one hundred
thousand lines per inch. It also varies a little in other ways,
some being strongly marked, others being more feeble and
difficult.
Now, we have several photographs of this diatom taken by
acknowledged masters, with every appliance at their disposal.
These photographs ought to show about thirty-three per cent,
more than can be seen visually, so that what is not there in
the photograph is almost certainly beyond the limits of
ordinary vision.
In Dr. Spitta's " Microscopy," we have on Plate IV, Figure 2,
a photo of the diatom with a Zeiss two-millimetre apochromatic
of N.A. 1 -30X 750. This photograph, then, ought to show as
much as the eye would see with the same objective, and under a
magnification of one thousand. It shows fine lines only, and
Dr. Spitta tells us in his text that this is what such an objective
should show, and I do not for one moment doubt that this
is all we ought fairly to expect. But notice, we have got above
our theoretical limits of useful magnification and still get only
lines shown.
In Messrs. Leitz's Catalogue of Photomicrographic
Apparatus, another photograph is found taken with an apochro-
matic two-millimetre objective, the N.A. of which is not given,
but is either 1 • 32 or 1 • 40. The magnification was one thousand
one hundred and fifty, and a deep blue screen was used,
needing an exposure of six minutes. This would give us as
much as the naked eye, X 1400 or so. Still we get lines only,
and again I insist that I do not doubt we see all that can be
expected. There is a faint suspicion that the lines are
serrated as if nearing resolution, but that is all we can say.
But again notice, we have got to nearly twice the old
theoretical limits of useful magnification and still get lines
only.
We turn again to Dr. Spitta's volume, and on Plate VI,
we find a magnificent photograph " taken (using blue light)
with a Zeiss two-millimetre apochromat N.A. 1-40 X 2,800."
He also notes that the dots are about the one-hundred-
thousandth part of an inch diameter " and that " these
are very difficult to see without the use of oblique green light,
even when employing the finest objective. A first-class semi-
apochromat should then show the dots furnishing an image
almost as good as that afforded by the apochromat," and so
on. I may add, the diatom is mounted in realgar, and is a
picked specimen of the well-marked type. The magnification
Shows as much as one of three thousand five hundred does
visually, i.e., nearly seven times the old theoretical limit ; and
now we get fresh structure, namely dots.
Thus, the old theories must be revised, or at least
modified ; seven hundred and fifty is not the extreme limit
of useful magnification. We may increase it to at least
1-50X100 .... , .1-50X100 , ,nn ...
= l,154,orperhapsevento =l,500,with
•13 H H -10
advantage. Our objectives will in this latter case be of much
lower aperture, especially compared with the focus, but this is
no difficulty, and the wise student will still use a low aperture
for the usual two-thirds (sixteen-millimetre) objective, one of
N.A. -65 to -75 for the one-sixth inch (4-2-millimetre),
and one of as high as he can afford for the one-twelfth inch
(two-millimetre) oil immersion. From the last alone he will
expect the utmost resolution. The others will show him all
that the eye can see without unduly forcing them by high
oculars, and altogether he will have a battery that will save
his eyesight, his patience and his pocket, and that will, above
all, never disappoint him or fail to show him all' that can be
shown.
The specialist may go a step further and obtain a one-
sixteenth inch oil immersion for the very highest power, not
in place of the one-twelfth inch, but to supplement it and to
prevent the use of too high an eyepiece. But it will be a
luxury and not a necessity — a specialist's motor compared to
the general practitioner's gig. For general work he will find
low apertures and medium eyepieces give him everything that
he can wish, and that the craze for higher apertures is the
mark of the dilettante and not of the worker, of the ignoramus
and not of the savant.
E. Ardron Hutton, M.A.
PHOTOGRAPHY.
By Edgar Senior.
PHOTOGRAPHY WITH A PIN-HOLE. — Having for
some time past devoted a considerable amount of attention
to the above, it was thought that the subject might be found
interesting to readers of " Knowledge " generally, as well as
to those in search of methods, more or less novel, for obtaining
photographs. Of course, it is not for one moment claimed
that the definition given by a plain aperture — or so-called pin-
hole— even approaches that of a high-class lens, yet the results
are by no means fuzzy or blurred, as the illustration, Figure 67,
from a pin-hole photograph taken by Mr. Alfred S. Gannon,
the subject being " St. Brelade's Church, Jersey," testifies.
Then again, as we do not in nature meet with that uncom-
promising sharpness which so many photographs exhibit — a
plain aperture will, in many cases be found to give more
artistic results, possessing those qualities termed by artists
" atmosphere," " breadth of effect," and so on, and in the case of
the photographing of buildings it is to be highly recommended,
since the image will be an exact facsimile of the object, with
an absence of that distortion so frequently seen in photographs
66
KNOWLEDGE.
February, 1913.
of a similar character. The one great drawback attending
the use of a pin-hole in place of a lens is the protracted
exposure necessary, which so limits ils usefulness
that, generally speaking, it is only in still-life subjects that its
application is really possible. On the other hand, one of the
advantages frequently claimed for the use of a plain aperture
in place of a lens is the readiness with which the size of the
image may be varied, merely by moving the plate nearer to, or
further from it, without the definition appearing to suffer to
any appreciable extent
When employing light of maximum photographic activity
the following formulae by Sir William Abney may be used : —
D =
120
D and L being measured in inches. Taking nine inches as
the distance of plate, the size of aperture would be found : —
V 9
120
3
120
1_
40
inch.
by so doing, the only
alteration being in the
amount of subject
which is included, and
which is dependent
upon the relationship
between the length of
the plate and its dis-
tance from the aper-
ture. Both theory and
practice, howe ver.agree
in showing that the
sharpest image is ob-
tained when a definite
relationship exists
between the distance
of plate and size of
aperture, and although
diminishing the aper-
ture may improve the
definition up to a
certain point ; beyond
this the reverse would
be the case, a result
explainable on the
undulatory theory of
light. It therefore
appears that the size
of the aperture " for the
best results " is regula-
ted by the distance of
the plate from it, and
the wavelength of light
employed in taking the
photograph. We have
before us as we write
a photograph of a point
of light taken with a
pin-hole of one hun-
dredth of an inch in
diameter : the image is
shown as a bright
centre surrounded by
eighteen alternately
bright and dark bands
(due to diffraction).
A second photograph,
taken with a larger
aperture, shows an
image of the same
point of light, as a
one dark band, with
of the first bright one.
I
Table 16, giving the
diameters of aperture
best suited to the
distance of plate, has
been calculated from
these formulae.
Diameter of Aperture.
inch.
i
inch.
?0
inch.
Distance of the Plate.
4
inches.
6
inches.
9
inches.
Figure 67. St. Brelade's, Jersey.
From a pin-hole photograph by Alfred S. Gannon. Diameter of aperture j^-inch
distance of plate 6 inches, exposure li minutes.
bright centre surrounded with only
a faint indication of the formation
This photograph exhibits the limit
to the size of the aperture for that particular distance of
plate, as if it be diminished beyond this, each point in a
luminous object would give rise to a spot surrounded by
alternately bright and dark rings, which would impart a
confused appearance to the photograph. The size of aperture
that will give the best definition from fulfilling the above
requirements has received the attention of more than one
eminent writer, and is given by the equation : —
where D is the diameter of aperture required, X the wave-
length of light, and L the distance of the plate from the
aperture.
Table 16.
We now come to the
question of the ex-
posure required ; but
this need not present
any real difficulty if
we remember that the
rule which governs it
generally equally ap-
plies here, and that it
may, therefore, be
obtained from com-
parison with a lens
aperture of known
value. Thus, suppose
it is desired to know
what exposure is
necessary to be given
with an aperture of
one - fiftieth inch in
diameter, to a plate at
six inches from it,
in comparison with a lens of six inches focus and stop three-
quarters of an inch in diameter (f/8). By the rule, the
exposures would be as (sV)2 to (J)2 or jsjiW to Ai so that the
plain aperture requires 1406-25 times longer exposure.
Therefore, if the subject required one-fifteenth of a second
when using the lens whose aperture was three-quarters of
an inch in diameter, by substituting the pin-hole whose
diameter was one-fiftieth of an inch, the required exposure
would be one minute thirty-three and three-quarter seconds.
It is therefore evident that the required exposures
may be readily calculated from the intensity ratios
of the apertures. In determining the exposure by this
method, the distance of the plate should be the same in both
cases, as the exposure required varies as the square of this
distance.
In order to avoid any calculations at the time of taking the
February, 1913.
KNOWLEDGE.
67
photographs, it is advisable to draw up a table of the
exposures required with plain apertures compared with those
of a lens, when used under various conditions ; such as speed
of plate, condition of light, time of day, time of year, distance
of object, and so on. With regard to the photographs them-
selves, they may be said to possess a charm peculiarly their
own, while at the same time the method of production is of
the most simple and inexpensive kind.
In making these apertures for use, the writer employs both
brass and aluminium foil (preferably the former) as the
materia], piercing the holes by means of fine needles, care
being taken that any slight burr round the edge is carefully
removed by rubbing on an oil-stone, so that there is no appreci-
able edge to interfere with the passage of light through them.
By examination from time to time under a microscope of
moderate power their condition is observed, and when satis-
factory the aperture is measured, and the foil containing it
mounted up in a frame of blackened card for use.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A.
PROPORTIONS OF SEXES IN EARWIG.— H. H.
Brindley finds that the proportions of the sexes differ con-
siderably in different localities in the same year and sometimes
differ considerably in localities quite near each other. The
proportions may differ appreciably in the same locality in
different years. This may be due to variation in the extent to
which the males survive the winter. There is a slight sugges-
tion that the percentage of males is higher on small islands.
The evidence that the characters of the soil or vegetation or
altitude affect the proportions of the sexes is exceedingly
slight. The normal length of life of earwigs is unknown.
Adult males are found somewhat rarely in the early months of
the year.
COLOUR OF FISHES. — The epidermis of fishes is delicate
and transparent. All the colour is in the dermis, and it
usually occurs in separate pigment-cells. These usually show
numerous radiating processes, and the pigment can be spread
out over a large surface or concentrated in the centre. This
depends on the expansion or contraction of the mobile
protoplasm of the pigment-cells. According to the pigment
they contain, — black, or yellow, red, and so on — the piginent-
cells are called melanophores, zanthophores, erythrophores,
and soon. Then there are other cells containing spangles of
the waste-product guanin, which are called iridocytes or
guanophores. They cause the silvery, metallic, or iridescent
appearance familiar on many fishes. But Professor Ballowitz
has recently discovered in the weaver and some other bony
fish, a new kind of chromatophore, not a single cell, but a
group of cells. Each melaniridosome, as he calls them, is a
cluster of iridocytes with an encapsuled central melanophore,
which sends its ramifying processes through the capsule in
complicated courses.
PARENTAL CARE AMONG ANTARCTIC ECHINO-
DERMS. — It is well-known to zoologists that many of the
Antarctic sea-urchins, sea-cucumbers, and other Echinoderms
show parental care, keeping their young ones sheltered about
their bodies and that in a striking variety of different ways.
Professor Ludwig has recorded ten cases of parental care in
Echinoderms from warm waters, and twenty-nine from the
Antarctic. Out of twenty-four different species of coastal
sea-urchins from the Antarctic, Mortensen reports that no
fewer than fourteen show parental care, and eleven of these
are littoral. The puzzle is why this habit, which is rare among
Echinoderms as a class, should be so common in the Antarctic.
An answer has been suggested by Hjalmar Ostergren (Zeit-
schrift wiss. Zool. C. 1912). He points out, first of all, that
the numerous sea-cucumbers which exhibit parental care in
the Antarctic, belong to families which are known elsewhere
to exhibit the same peculiarity. He points out, in the second
place, that the distribution of land and water in the south is
quite different from that in the north, and that for coastal
Echinoderms everything is against the success of free-
swimming larvae. The low temperature of the water and its
low salinity tend to bring about a shortening of the life-history
or at least a suppression of free-swimming larval stages. In
point of fact, only three or four cases of free-swimming
Echinoderm larvae are known from Antarctic seas.
CORRESPONDENCE.
SQUARING THE CIRCLE.
To the Editors of " Knowledge."
Sirs, — In a letter in the November issue of "Know-
ledge," " Geoma " gives a method of " squaring the circle,"
stating that the perimeter of a circle of unit diameter is equal
to that of a certain triangle. This amounts to no more than
the statement that t = \/5 + 1 approximately. This is not in
itself a good approximation to the value of w and it would be
quite easy to draw a triangle whose perimeter gave a much
closer approximation. But, however close the approximation,
we should be no nearer " squaring the circle " by geometrical
methods.
3, St. John's Road, R. J. POCOCK.
Oxford.
THE FOURTH DIMENSION.
To the Editors of " Knowledge."
Sirs, — Referring to recent letters on this subject which have
appeared in " Knowledge," I have been rather struck by
the fact that few of your correspondents seem to have clearly
distinguished between what is possible, what is imaginable,
and what has a real physical analogy and bearing. The
argument that the existence of one or two dimensions implies
a third, and the third implies a fourth, and so on ad infinitum,
seems to me utterly without value from the following very
simple consideration. Objects and space of one and two
dimensions only are purely mental abstractions. All bodies
to be seen at all or even clearly apprehended, in my mind, must
have three dimensions, neither more nor less. The geometrical
point must have some bigness, some (however small) depth ;
the line must have at least a slight breadth and thickness
(i.e., three dimensions, though one greatly predominates, and
the others may be disregarded except the fact of their
existence). It is a result of experience that three numbers
are, in general, necessary to define the position of any point
with regard to any other ; in algebraical language, the x, y,
and z coordinates. If one of these coordinates, say the z, be,
or is assumed to be, the same for all points, we have the x
and y coordinates only, the coordinates of plane geometry,
and lastly, for a common y we have all the ideal points lying
on a straight line (the axis of x or any straight line parallel to
it in the plane xy, z — OorC). This, in common sense language,
is all that the whole thing means, as we have pointed out
elsewhere (Quest, English Mechanic, and so on).
By the algebraical methods of coordinate geometry a vast
body of geometrical theorems has been shown to have
algebraical parallels, and conversely, theorems applying to
curves and surfaces in general have been discovered by the
application of analysis to the coordinates x, y, and z. It is
possible (and has actually been done) to introduce a fourth
coordinate, w, or, indeed, any number of fresh coordinates,
and by algebraical methods to deduce theorems of great beauty
and interest, but the results will have no geometrical
68
KNOWLEDGE.
February. 1913.
parallels. Some mathematicians have even discussed some
problems of motion, using the three coordinates, x, y, and z,
and the fourth w to represent a fourth dimension, and their
results are given in dynamical works, just as we find problems
as to the motion of bodies under laws of force differing from
that of nature (inverse cube, inverse fifth power, direct
distance, and so on) set for the edification and amusement
of students. Of a somewhat different character is the
question as to the curvature of space, which, we are told,
may possibly be some day detected by astronomical observa-
tions. At present, however, we find that the Euclidian
" homaloidal " space agrees most closely with the space of
experience and is the simplest concept, but there are other
concepts which within the limits of observational error give
results differing but little therefrom. If some day the existence,
say, of stars with negative parallaxes be definitely ascertained
' lying on the other side of nowhere," some mathematicians
may regard this as a proof of the non-Euclidian nature of our
space, but meanwhile astronomers generally will be likely to
find a simpler explanation.
Walthamstow.
F. W. HENKEL, B.A., F.R.A.S.
THE FOURTH DIMENSION.
To the Editors of " Knowledge."
Sirs, — I notice in the November number of " Knowledge,"
that Mr. John Johnston still continues the (as I think)
unprofitable exercise of criticising a theory, with the arguments
for which he has not taken the trouble to acquaint himself.
Mr. Johnston says that "Our experience of dimensions gives
us the law that where there is one there must be three, but it
gives us absolutely nothing else. There is nothing in it to
lead us to believe, or even to suggest to us, that there are
other dimensions." On the other hand, I say that the exist-
ence of any number of dimensions (say n) implies the existence
of one more dimension (« + l), and so on, ad infinitum. In
support of that statement I have brought forward certain
arguments, to which I have referred Mr. Johnston. Now,
these arguments of mine may involve a fallacy. I may have
misapplied the principle of the continuity of natural law, or
committed some other logical mistake. If so, I am quite
willing to relinquish a belief in the real existence of the fourth
and higher dimensions ; since this belief does not form an
integral part of my philosophy, but is merely an appendage
thereto, supported only by its own specific arguments. But if
this be the case, let Mr. Johnston point out the fallacy in my
argument ; not content himself with making bland assertions
and negations without first finding out what this argument is.
If Mr. Johnston does not wish to do this, then let the
correspondence cease, since it is only a waste of time and the
valuable space of your journal ; for I must confess I am not
sufficiently anxious to convince Mr. Johnston of the correct-
ness of my views as to the fourth dimension to the extent
either of restating them in a letter, or of sending Mr. Johnston
a gratuitous copv of my book.
H. STANLEY REDGROVE.
The Polytechnic,
Regent Street, London, W.
P.S. — Reading Mr. Johnston's letter my eye caught that of
its companion signed " Geoma." I thought that Professor De
Morgan had annihilated the last circle-squarers, and that the
species was now extinct. "Geoma" may easily satisfy him-
self of the inaccuracy of his " theorem " by measuring the
diameter of a cylinder with calipers and its circumference
with thread, since it is quite easy to get the value of the ratio
(*) by this means correct to two places of decimals : that is,
3-14. Of course, as I e<pect all your readers know, it has
been conclusively proved by the higher mathematics that the
value of this ratio is an incommensurable quantity, and that
to five places of decimals its value is 3- 14159.
A BAROGRAPH RECORD.
To the Editors of " Knowledge."
Sirs, — The wet weather we have experienced since the
15th of July, though that day was fine and bright with us, is,
probably, a fair A,
//PhJ/frn JJh SJ*l.
fyPo
• 7
7°
Jo\
sample of the kind
of weather that
originated the leg-
end of St. Swithin.
My Barograph
has been com-
paratively un-
changed during
this period of rain
and wind, but the
accompanying re-
cord (see Figure
68) of a thunder-
storm here on the
night of May 11th
and 12th last, is
quite unpreceden-
ted during the last ten years
your columns.
JOHN GLAS. SANDEMAN.
Whin-Hurst, Hayling Island.
ON COOKED FOODS.
To the Editors of " Knowledge."
Sirs, — I read with much interest, the article in the October
number of " Knowledge," by Katharine I. Williams, but
would like to ask how her values would stand if the vegetables
were cooked conservatively and did not come in contact with
the water in the process.
It is not denied that the old-fashioned method of cooking
vegetables is wasteful and foolish in the extreme.
Figure 68.
and may be worth notice in
13, Shaftesbury Road,
Hornsey Rise, N.
A. GAUBERT.
SCHOOL SCIENCE SOCIETIES.
One of the topics discussed by the Association of Public
School Science Masters at their meeting, held at the London
Day Training College, on the 8th and 9th of January, was the
aims and uses of School Science Societies. The general
principles were dealt with by Mr. W. M. Hooton, of Repton,
and after considering the general advantages of such societies
and their kinds, he spoke of the limitations imposed by
organised games, which, very many will agree, stand greatly
in the way of the boy whose tastes and inclinations would
lead him to acquire knowledge first hand and in his own way.
Mr. Hooton emphasised the point that, in his opinion, organised
games did not so much use up the time of the boys as their
energy, and left them too tired for other pursuits. In either
case the result is the same. With all due respect to
Mr. Hooton's contention, we think that a trustworthy boy
who would prefer taking a ramble in order to study some
scientific subject as a hobby, to playing games should be
allowed to do so. Mr. Hooton also testified to the good
training obtained by boys in preparing lectures and illustra-
tions. Mr. F. C. Headley, of Haileybury, when discussing
School Natural History Societies, dwelt on the need for
unspoilt country to be within easy reach. He said that at
private schools many boys with a definite bent for Natural
History had the enthusiasm starved out of them. Liberty and
leisure, he claimed, were important things. Some of the leading
boys should be enlisted as supporters, and it should be made
clear to them that Natural History leads on to the study of
evolution and to many difficult problems, and is not merely
an amusement for little boys.
Geological Societies were advocated by Mr. C. I. Gardiner,
of Cheltenham; Photographic Societies, by Mr. T. H.
Oldham, of Dulwich, and Astronomical Societies by Mr. G.
Hewlett, of Rugby.
SOLAR DISTURBANCES DURING DECEMBER, 1912.
By FRANK C. DENNETT.
December was very cloudy, and hence the record is some-
what imperfect, no less than eleven days having been missed
completely. On six days (2, 3, 8, 9, 10, and 28), the disc
was apparently free from disturbance, and on one, the 23rd,
only faculae were seen, spots being visible on the remaining
thirteen. The longitude of the central meridian at noon on
December the 1st, was 54° 36 .
No. 24. — First seen in a faculic disturbance a little way on
the disc from the eastern limb on the 12th, a spot with tiny
pores, some before and some behind it. On the 16th it
showed two distinct umbrae. The larger spot had seemingly
length, seen on December the 17th, only one of which, the
leader, was found next day. Its place was marked on the
20th by a faculic area.
No. 26.— A group of spotlets and pores, 46,000 miles in
length, first seen on the 29th, which changed its appearance
considerably during its visibility, being last seen amid faculae
close to the north-western limb on January 3rd.
During the past year only 27 outbreaks of spots have been
recorded, one being of a secondary character. Of these. 22
have appeared in the southern hemisphere, and only five in
the northern. It is somewhat singular that in December, 1911,
DAY OF DECEMBER, 191 2.
E
1 3.
JO. 1
1 P-
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23.
22
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9
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so m no a 130 ho 150 m 170 iso bo
IB 210 230 2*0 250 260 270
790 300 310 320 330 340 350 360
broken into two next day, and on the 18th was much less
conspicuous, not being seen after.
No. 24fl. — This disturbance, certainly connected with the
last, appeared some 50,000 miles in front of it, on the 16th —
if not on the 15th — a spot with some pores round. On the
17th two dark penumbral spots had developed almost midway
between the southern components. On the 18th the rear spot
of this group had formed, nearly equal to the leader. On the
20th, both these spots were still visible, but on the 22nd only
the leader remained amongst a quantity of faculic matter,
whilst this spot was not to be seen on the 23rd, only the
faculic remains of the outbreak. The length of No. 24 was
30,000 miles, a. 45,000, and the double group 82,000 miles.
No. 25. — A group of spotlets and pores, 35,000 miles in
a little disturbance broke out in 23° N. Latitude, and now
again in December, two disturbances have made themselves
visible, one in 17°, the other in 27° N. Latitude. These may
prove to be the forerunners of a new cycle of solar phenomena.
The second chart shows the distribution of the spot distur-
bances during the year. The collection of disturbances into
groups is again a noticeable feature in the southern hemisphere.
One chain of activity extends from 350° to 82°, and another
from 153° to 220°, and a third from 228° to 330°, many of the
second group drawing very near the equator. Of the 53i days
upon which the Sun has been observed, spots were recorded
on 108, faculae were seen on 99, whilst on the remaining 126
the disc presented an unruffled surface.
Our monthly chart is from the combined observations of
Messrs. J. McHarg, A. A. Buss, E. E. Peacock, W. H. Izzard,
and the writer.
DISTRIBUTION OF SPOT-DISTURBANCES DURING 1912.
20
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0 » 20 JO tt 50 60
80 90 100 IB 120 ISO 140 150 160 170
200 210 220 230 2(0 ZSO 30 IV mi 290 300 310 $20 130 340 350 360
69
SOME EFFECTS OF THE HOT, DRY SUMMER OF 1911
By LIONEL E. ADAMS, B.A.
It was natural to expect that the exceptional tropical
heat and the drought of the summer of 1911 should
produce some effect on the fauna and flora of our
island, which is only at rare intervals subjected to
such conditions, and this expectation has been
fulfilled.
Perhaps the most noticeable feature of the season
was the phenomenal abundance of wasps. On
August 16th a neighbouring keeper and I took
sixteen nests in two fields, through which the river
Mole flows. By the way, the quickest and altogether
most effective method of taking wasps' nests is by
means of a solution of two ounces of cyanide of
potassium to one and a half pints of hot water, cold
water failing to dissolve the cyanide. One pound of
cyanide costs three shillings at the chemist's, which
amount will make enough solution for fifty nests.
A wineglassful should be poured into the entrance
holes of the nests. Then watch — you will see the
wasps continue to come in for an hour or two, but
vestigia nulla retrorsum. When all have entered,
the nest may be safely dug out ; but if left till the
next day the fumes of the poison will have evaporated,
and the wasps hatched after that will be found alive
and stinging. A great advantage of this method is
that it can be carried out in daylight and without
much danger of being stung.
In contrast to the abundance of wasps was the
comparative scarcity of flies. This was due to two
causes ; first, they are the prey of wasps, but per-
haps more especially because the drought had
deprived the manure and refuse heaps of the mois-
ture necessary for the well-being of the fly larvae.
A great abundance of the Peppercorn Oak-gall
was noticed in Surrey by Sir Jonathan Hutchinson
and Dr. T. A. Chapman, and recorded by the latter
in the September number of the Entomologists'
Record and Journal of Variation.
In the same number Dr. Chapman and other
entomologists record an unusual abundance of
Pieris rapae, the Small White Butterfly, and also an
unusual proportion of small individuals of this
species as well as of P. napi. Dr. Chapman
explains that this dwarfing is caused by the heat
forcing the larvae to maturity and pupation before
they had time to eat enough to grow to their normal
size, and not by any deficiency of food.
Also, in the same number of the journal, another
observer notices an insufficient colour supply and
albinism whole and partial in the genus Colias in
Switzerland.
In certain gardens in Reigate there was practically
no aphis, though their enemy, the ladybird, was also
scarce.
Owing to the drought land snails on which the
thrushes feed remained in hiding, and a friend of
mine found in Northamptonshire several thrush
" anvils " (that is, stones on which the birds break
the shells to extract the animal) surrounded by
broken shells of the large water snail, Litnnae
stagnalis — a most unusual food of thrushes.
The keeper above referred to, and some of the
neighbouring farmers, informed me during the
drought, that they found thrushes and other birds
dead, presumably on account of scarcity of worms
and slugs.
I fully expected to find an unusual number of dead
shrews along the roads and lanes, but to my surprise
I found far fewer than usual. However, as I
happened to be trapping shrews throughout the
summer and autumn a great number passed through
my hands, and I noticed that their coats were
markedly paler than usual, and that about twenty-
five per cent, had white ears, whereas the normal
percentage of white-eared specimens is four or less.
Moles were affected by the drought in a curious
manner. From three different sources I heard the
same story of dead moles being found about the
lanes and fields in large numbers. These had died
of starvation.
One farmer of a hundred acres made a practice of
going out with his dogs at night to hunt moles, and
killed over a hundred in this way. It is usual for
moles to come to the surface during the nights of
summer and early autumn after worms; but last season
they fared badly in two ways — worms were scarce
from want of dew and rain, and, moreover, the ground
was caked hard and difficult for worms to work
through. Also, when once above ground, the moles
found a similar difficulty in burrowing out of sight
before their enemies were upon them.
In our Reigate garden and all round the neigh-
bourhood the Jerusalum artichokes (Helianthus
tuberosus) blossomed.
Early in August the leaves of various trees turned
yellow and began to fall. The bracken began to fade
at the same time, and by August 20th there were
several large patches of dead bracken on the heaths
in Surrey.
During the present year Yuccas have been abnor-
mally prolific in bloom, and one of the gardeners at
the town's public gardens attributes this to the heat
of last year " ripening them up."
A paradoxical incident occurred which was exceed-
ingly puzzling till the probable explanation occurred
to me. Two springs which had run dry at the
beginning of August started running again at the
end of the month, although there had been no more
rain. I could only account for this by supposing
that more cracks had gone on developing in the dry
ground till water was reached further back in the
water-bearing bed.
70
THE PROBLEM' OF THE MOON'S ORIGIN.
By B. G. HARRISON, F.R.A.S.
The air of mystery which always enshrouds the
Moon compels even the most unreflective of us to
speculate upon its past history. A world devoid of
life, one pictures the vast upheavals and intense
convulsions that must have taken place to have
moulded the landscape into its present chaotic form,
which bears witness to its former tempestuous exis-
tence. Seen through the telescope, one is impressed
by the sense of utter loneliness and desolation that
seems to prevail everywhere, while the apparent
permanence of each feature on the lunar surface
makes one wonder how long this changeless aspect
has continued. Indeed, there are few problems con-
nected with astronomy so fascinating as that of the
origin of our satellite, more especially since any
knowledge of its past would be of infinite assistance
in helping us to frame the general theory of cosmical
evolution.
Apart from the fact that the Moon is our nearest
neighbour and the most familiar of all the celestial
bodies, the evidence of its formation is considered to
be of a far more conflicting nature than in the case
of any other portion of the solar system, and for this
reason alone presents features of the greatest
interest.
There are, of course, only two ways to which our
satellite could have attained its present position. It
may once have been a minor planet which ventured
too near the Earth and was consequently captured
by the latter ; or else it must at some remote period
have formed part of our globe and have been separated
from it by rapidity of rotation. Before considering
these alternatives in detail it will be perhaps as well
briefly to outline the most usually accepted hypo-
thesis of planetary evolution.
The general features of Laplace's celebrated
nebular theory are well known. This illustrious
mathematician suggested that our system was
originally a nebulous cloud or " firemist" of glowing
gas, which gradually contracted, throwing off rings
in the process. From these rings the planets were
evolved and the nucleus eventually condensed to
form our sun. Laplace himself advanced this theory
with considerable mistrust, and recent research has
caused several modifications to be made in his
hypothesis.
In the first place, the original high temperature
with which he endowed his nebula is now considered
unnecessary. It is realised that the actual contrac-
tion of the gaseous mass would provide all the heat
required to account for the present observed tempera-
ture of the sun and planets, even after due allowance
is made for loss by radiation entailed in the process.
Secondly, it is thought very improbable that the
nebula could ever have had a sufficiently rapid rotation
to detach the rings. Even if these were detached,
the result has not been quite what we should expect.
Theory demands that the width of these rings should
be infinitesimal, since otherwise the outer portion
would revolve more rapidly than the inner and thus
upset their dynamical equilibrium. As the accelera-
tion of rotation would probably proceed at a uniform
rate there should have been a vast number of these
situated at intervals bearing a fixed ratio to each
other, thus giving the transformed nebula a perfectly
symmetrical appearance. Even if it were possible
for the rings to condense into planets, which seems
doubtful, we should expect their masses to bear a
more constant proportion to one another than is
actually the case. Perhaps a still more unfavourable
argument to this idea of our system's development
lies in the fact that amongst the vast numbers
of nebulae which have been discovered, none
afford any convincing evidence of concentric ring
formation.
It is generally far more easy to detect faults in the
theories of others than to provide a thoroughly satis-
factory hypothesis in their place, and critics have
found the case in point no exception to the rule.
Nevertheless, numerous suggestions of more or less
merit have been advanced from time to time, but as
space will not permit of their consideration in detail,
we will confine ourselves to outlining what is perhaps
the most feasible theory of planetary evolution. To
do this it will be necessary to go back an epoch
further than Laplace did, and consider the actual
.formation of the primordial nebula. It is thought
probable that this was caused by the near approach
of another star to our sun, which at that remote
period may have been simply a dark body. It is by
no means necessary for an actual collision to have
taken place, since the disruptive action caused by
the different portions of each sphere being at varying
distances from the common centre of gravity, and
thus being pulled with unequal force, may have been
quite sufficient to tear them both apart and scatter a
portion of their contents into surrounding space.
Now there are three possible courses for matter
thus ejected to pursue. Either to follow a path by
which no return to the system would ever be
possible, to fall back to the Sun itself, or to revolve
around him in elliptical orbits. If our luminary
were travelling in a straight line, and in the absence
of any other perturbing force, all matter would
follow one of the first two courses, according to the
force of ejection. It is necessary, therefore, to
assume that either owing to the action of the
disturbing stranger, or else through collisions
amongst themselves, the paths of some of the
particles were altered, and they were forced to
permanently revolve round the Sun, thus forming
our embryo solar system. It is probable, in any
case, that a large proportion must have followed one
of the other alternatives, and so have either increased
71
72
KNOWLEDGE.
February, 1913.
the temperature of our luminary, or else have been
lost to the system for ever.
We imagine that the Sun was rotating before the
initial catastrophe occurred, since this motion would
give a preponderance of direct revolution amongst
the ejected particles, although it is likely that that
of a large percentage may have been retrograde. This
diversity of motion would naturally cause frequent
collisions, and in this way other small centres of
gravity would gradually be formed. As these centres
increased in size, their attraction would deflect
neighbouring particles from their original course and
cause them to revolve round them. Further
collisions would ensue amongst the captured frag-
ments, involving a consequent loss of energy,
and they would thus be slowly drawn nearer
to, and finally upon, their various centres of attrac-
tion, while the dismembered remains of the original
sun, being in the centre of the nebula, would succeed,
owing to their superior mass, in gathering up the
greatest portion of the scattered contents.
We may thus endeavour to picture to ourselves
our system slowly evolving, a vast aggregation of
particles of various sizes, extending far beyond the
present orbit of Neptune and becoming more and
more scattered as the distance from the common
centre increased. Occasionally we should witness
the collision of two fragments, and the consequent
generation of light and heat, and we should also
observe the increased frequency and violence of
these collisions in the vicinity of the Sun. Although
individually presenting every diversity of movement,
these particles would in the aggregate present a
certain orderly sequence, and a series of vortices
would be noticeable revolving round the Sun in the
same direction as its own rotation, the larger ones
lying in substantially the same plane : that of the
disturbing star's approach. The general appearance
of the system would closely resemble the spiral type
of nebulae which have been revealed to us in such
numbers by the telescope and the photographic
plate in recent years. It is a significant fact that
all these nebulae consist of two arms emanating
from a central nucleus at diametrically opposite
points. So far as we are aware the only force
capable of producing this symmetrical appearance
is that of disruptive tidal action, since, were the
coils thrown off owing to rapidity of rotation, jets
of matter would be ejected from every part of the
circumference, and if by explosive force from
indiscriminate points on the surface.
This, then, is the modern idea of the primordial
nebula, a somewhat different one from the conception
of Laplace, insomuch as it consists of independent
particles revolving round a common centre of gravity
in elliptical orbits instead of a slowly rotating sphere
of glowing gas. It also has this advantage, in that
it presents a complete cycle of events, from star to
nebula and from nebula to star. This is analogous
in our conception of the infinite to the difference
between a circular and a straight line. There is less
difficulty in imagining the former as endless than
the latter, although the origin of either may be
equally incomprehensible to our finite minds.
It must not be imagined that the hypothesis here
outlined is entirely satisfactory, but as there appear
to be fewer drawbacks attached to its acceptance
than to that of most of the theories that have been
advanced from time to time, it is generally considered
probable that our evolution proceeded somewhat on
these lines. Accordingly, it would appear natural
that the planets and their satellites were both formed
by the capture and aggregation of smaller particles
in the same way. The lesser whorls would control
the particles in their immediate vicinity, but would
themselves be under the attraction of the larger
vortices, just as these would in their turn be con-
trolled by the Sun.
It is, of course, mathematically impossible for one
body to capture another without the intervention of
a third force. This may be illustrated by the case
of a comet approaching our solar system. If the
former is a wanderer from interstellar space it is
obvious that although the solar attraction will
enormously increase its velocity as it draws nearer,
after the comet has passed perihelion, the Sun will
only be capable of controlling the same speed as it
was able to impart, and the visitor will leave the
confines of the solar system with its original
momentum unimpaired. If, however, the comet
passes near one of the planets, the attraction of the
latter may more than counterbalance the initial
velocity of the comet, and thus change its hyperbolic
orbit into an elliptical one. Another means whereby
a portion of the wanderer's energy could be dissipated
is by moving through a resisting medium. This is
a more satisfactory method of accounting for the
capture of a satellite than by means of a third
attractive force, since the latter would as often free
the satellite from the control of its primary, as assist
in making it captive.
The capture theory, therefore, demands as a
necessary condition the existence, at all events in
the past, of a resisting medium. Professor See, to
whom the development of this hypothesis is due,
considers, and not without reason, that the presence
of this medium was very probable. For it is almost
certain that the vast quantity of gases which would
have been liberated with the more solid matter at the
birth of our solar system, would have existed in the
free state as a nebulous cloud for untold aeons
before combining with these solid elements, or
forming the atmospheres of the various worlds in
the course of evolution. This would render it
possible for a satellite entering the sphere of a
planet's influence to be eventually retained by the
latter, and would also have the effect of decreasing
the satellite's orbit. It would at the same time
cause an eccentric path to become more circular,
since a circle encloses a larger space than any
other curved line of equal length, and a body can
consequently revolve round a certain area with
less expenditure of energy if moving in a circular
orbit than if travelling in one of any other form.
February, 1913.
KNOWLEDGE.
73
Now, the sphere of the Earth's influence extends to
a distance of over nine hundred thousand miles, so
that any small body revolving within this distance
would be entirely under the Earth's control, and
since the Moon is less than two hundred and forty
thousand miles away, its position, and the circularity
of its orbit, could most easily be accounted for by
this supposition. The same remark applies to all
the known satellites of the other planets, which are
in every case well within the space controlled by
their respective primaries, and which, with the
exception of the outer ones of Jupiter and Saturn,
have remarkably circular orbits.
Owing to the unique nature of the Saturnian
system it has frequently been typified as an example
of cosmical evolution. Thus, at the time when
Kant and Laplace framed their theories, the rings
were thought to consist of gas, and, therefore, to
corroborate them. The rings have since that time
been conclusively proved to be formed of vast
numbers of independent particles revolving round
their primary, but were still considered to be a
satellite in course of formation. Edouard Roche,
a French mathematician, has, however, shown that
it is impossible for a satellite to exist within
2-44 radii of its primary, owing to the strain
imposed by the attraction of the latter. It is,
therefore, probable that if a resisting medium exists
in the solar system, a satellite may have actually
been brought by its influence within the pro-
scribed area and been torn to pieces, the rings thus
being an example of the end rather than the birth
of a world.
The thesis of possession by capture would con-
sequently account for the presence of the satellites
under the control of their various primaries in the
most likely manner. Indeed, were it not for the
conflicting testimony offered by our Moon, there could
be but little diversity of opinion on the subject. It
will be as well, therefore, to examine the evidence
regarding our own domestic system somewhat more
fully. There is, of course, only one other possible
way to account for the present position of our
satellite, which, if it has not been captured, must
have been formed by fission of the Earth, and this
latter theory seems to have met with almost
universal acceptance ever since the time of Anaxa-
goras, 500 B.C. Now, there is one unusual feature
about the Earth- Moon system favourable to this
hypothesis, namely, the relative sizes of its two
constituents, which are in the ratio of eighty-one to
one. If we except Neptune and his satellite, about
which some doubt exists, the nearest approach to
equal masses in the other planetary systems is to be
found in that of Saturn. His largest satellite,
Titan, is but the one four thousand seven-hundredth
part of his mass, and there is a still greater dis-
crepancy in the relative sizes of all the other
satellites to their primaries. This peculiarity of
our Moon might, therefore, seem to imply a different
origin from that of other satellites^although, if it ever
revolved against resistance, there is no dynamical
reason why our Earth should not have captured such
a comparatively large globe.
There are, however, several objections to the fission
theory. In the first place, it would be necessary for
the Earth to have attained a sufficiently rapid
rotation to have overcome the force of gravity by
centrifugal force. The alternative to this would
be to assume that the rupture was caused by tidal
strains, in the same way as that suggested in the
evolution of the solar system. Now, if this had
happened, two streams of matter would have been
ejected and formed a small spiral nebula. It is
extremely unlikely that all the meteorites forming the
coils would have only condensed into one other body,
since we should expect a miniature solar system of
our own, with some satellites considerably nearer
than the lunar orbit, and others further off. More-
over, the presence of the disturbing element would
have to be accounted for. Unlike the strange star
which is supposed to have caused the birth of the
primordial nebula, this second sphere would pro-
bably be unable to escape from the control of the
Sun, and as it would necessarily be of considerable
size to cause the requisite amount of damage, its
presence could almost certainly be detected ; for even
were it now beyond the range of our telescopes, we
should in all likelihood notice its perturbing effect on
the outer planets. As we know of no such body,
we are forced to discard this surmise and fall back
upon a rapid rotation as the only cause of fission.
It has been calculated that, in order to overcome
the adhesion of its particles by centrifugal force, our
planet would have to possess an axial rotation of
two hours and forty-one minutes. The only means
of obtaining this enormous velocity would be by
contraction from a nebulous condition. To appreciate
this process it is necessary to understand what is
involved in the term " moment of momentum." It
is well known that momentum is the product of the
mass and velocity of a body, and " moment of
momentum " denotes its rotary power round an
axis. If we neglect outside influence it is manifestly
impossible to alter its amount in a rotating body,
however much the latter expands or contracts.
Whatever it loses, therefore, in decreasing size, is
compensated by an increase in angular velocity, or
in other words, in a contracting body, rotating freely
in space, the angular velocity varies inversely as the
square of the radius.
Now, this increase is considerably in excess of the
additional speed required by the particles of a body
to counteract the increase of centripetal force, due
to their nearer approach to the centre of gravity.
Thus, although the Earth is thirty times nearer the
Sun than the planet Neptune, its angular orbital
velocity is only one hundred and sixty-five times
that of the latter, whereas the contraction of a rota-
ting sphere to one-thirtieth of its original diameter
would result in an increase of 302 or nine hundred
times its initial angular speed.
If, therefore, the Earth were sufficiently diffuse, and
its original rotational velocity were rapid enough, it
74
KNOWLEDGE.
February, 191
would be quite possible for it to disintegrate when
sufficiently contracted. Unfortunately, we cannot be
at all certain that the rotation of the Earth has ever
been much more rapid than at present ; although,
could any evidence be advanced in its favour, it
would remove one of the greatest objections to the
fission theory. It might be expected that the earth
would still show some signs of the distortion of its
surface which a more rapid rotation would involve ;
but it is rather significant that no facts of any convinc-
ing nature exist to testify to this either in physics or
geology. It is, of course, possible that time may have
obliterated any evidence that has been left us, but it
is by no means certain to have done so.
Although this is not a very conclusive argument it
is nevertheless unfavourable to the idea of a rapid
rotation, and if we examine the other members of
the solar system for any evidence regarding the
original length of our day, the result is equally
unsatisfactory.
(To be continued.)
REVIEWS.
ANTHROPOLOGY.
Malta and the Mediterranean Race. — By R. N. Bradley.
336 pages. 1 Map, 54 Illustrations. 9-in.X6-in.
(T. Fisher Unwin. Price 8/6 net.)
Mr. Bradley's book is crammed full of interesting facts,
contentions, and suggestions, and bears out Professor Sergi's
theories to a very considerable extent. From a glance at the
title one might think
that the work had little
relation to our own
country, but it would
seem that English
people are largely of
the Mediterranean race,
though by no means of
so pure a type as the
existing Maltese; but it
is said that judging only
from the looks of the
men and women with
grey or blue eyes, one
might imagine oneself
in Ireland instead of
Malta. The chapter
showing the traces of
the Semitic language
which are to be found
in our own is particu-
larly important, and
the illustrations given
by no means exhaust
the results of Mr.
Bradley's researches.
The " ash " tree has
the same name in
Arabic and comes from the word ash, meaning " to nest,"
as it is a favourite nesting tree ; " dally " is from the
Arabic " dall " to be coquetish with ; " merry " is not much
changed from the Arabic " marih," to be lively. The Arabic
" silak " meaning spun thread, by the loss of the "a" becomes
" silk," and in the same way "atan," to macerate hides, becomes
" tan." Mr, Bradley goes carefully into the monuments of
Malta, the dolmens, which he looks upon as imitation caves,
and the secondary burial of human bones after the removal of
the flesh, common to Malta, Sicily, Crete, and Ancient
Egypt. There is also much attractive matter with regard to
designs, to ladies' dress, to the characteristics of the ancient
and the modern Maltese, and that in times gone by. as at
present, stout people were admired is shown by the discovery
of steatopygous figures. The connection between Kaffirs and
the more northern peoples which gave rise to the Mediter-
ranean race is discussed, and allusions made to the votive
axe in stone and copper, which is common throughout the
Mediterranean. The examples of polished axe amulets seen
in Figure 68. which we have borrowed, are from Malta.
Mr. Bradley shows, from an examination of old and recent
By the courtesy oj
Figure 68.
Polished Axe Amulets of Hal Safliena, Valletta Museum.
(From "Malta and the Mediterranean Race.")
skulls, that the Maltese were and are very pure examples of
the Mediterranean race. Many of the subjects dwelt upon
are illustrated, and after a short account of Maltese folk-lore,
short heads are compared with long. It is common knowledge
that these two types exist side by side in this country, and we
quote the following observations which Mr. Bradley has made
on two of his friends: "I call to mind my longest-headed
friend, now no longer living ; a man of generous emotions
and strong sympathies
and antipathies, his
fancy led him to lengths
from which extrication
was difficult, and his
changeableness, depen-
dent on his nioods.
made his conduct
alarmingly inconsistent.
Yet, when once you
knew him well, he was
the most loveable of
men. Moreover, he
was a genius and a
poet. I have studied,
too, a short-headed
acquaintance with much
interest ; he has no
pretentions to brilliance,
and never launches
forth into enthusiasms
or ecstasies. But he is
perhaps the most
punctual, conscientious,
trustworthy person I
know. He is, above
all things, a safe man,
and his greatest merit
is his efficiency."
ASTRONOMY. W. M. W.
The $>tory of the Heavens, Part I. — By Sir R. S. Bail,
M.A., LL.D., F.R.S. In 14 monthly parts. 48 pages.
18 illustrations. 9|-in..X 6-in.
(Cassell & Co. Price 6d. net.)
The parts received initiate a new edition of this already
well-known book, which first appeared about twenty years ago
in a very similar form.
The part before us consists of forty-eight pages with plates
and a large frontispiece or chart, in blue, of the northern
heavens ; so that we may expect a book of about seven hundred
pages. From our experience of the early edition, the book
was much too thick for convenient handling, by day or by
night, so we had it bound into two volumes of about one and
a quarter inches thick, and they form books that can be used
by a child or when reclining in a chair. May we express our
wishes strongly to the author and publishers that they will
consent to adopt the plan of dividing the book into two ;
February, 1913.
KNOWLEDGE.
75
there need be only one good index at the end of volume II.,
and a title-page to each ; the pages might and should run on.
As we use books for many hours daily we offer this
suggestion, and feel sure that the step would be in the right
direction and none would regret it ; the increased cost would
be very trivial, the convenience very great. Books for use are
made far too heavy and thick nowadays.
As to the contents; the story is naturally told in the author's
most pleasant, entertaining and well-known way, and it comes
from a master hand. Judging by the experience of the
previous edition the whole ground of astronomy in its popular
aspect will be covered. The part before us does not indicate
how far the subject has been re-written or revised to date.
In future parts that may be judged. In several departments
of astronomy, mainly solar and stellar, immense progress has
been achieved by that ubiquitous handmaid — photography,
and we hope that the advancements may be frequently intro-
duced into the text and plates.
We heartily commend the book to all those who love to
read, and to know more about the objects and worlds beyond
our own puny Earth.
F. A. B.
Astronomy. — By F. W. Dyson, LL.D., F.K.S. 118 pages.
60 illustrations. 6:j-in. X4i-in.
(J. M. Dent & Sons. Price 1/- net.)
This is one of Dent's Scientific Primers, edited by Dr. J. R.
Green. The little book before us is virtually a condensed
second edition of the author's larger work upon the subject
published in 1910. The only portion that has been materially
curtailed is Chapter VIII, on the Fixed Stars, which has been
reduced to a microscopical quantity of six pages. The bulk
of the book consists of three chapters, forty-four pages of
historical astronomy, naturally condensed, but replete with
information very much to the point and interestingly given ;
the fourth Chapter we might call the practical chapter, as it
relates to the instruments with which astronomers work ; the
next forty-four pages form Chapters V, VI, and VII, and
include the Sun and Solar System, with information to 1908,
and numerous illustrations.
Thus we have in about a hundred pages a concise history
of astronomy for more than two thousand years, with few
omissions of the important facts which form the eras of
astronomical progress, in a neat form and size for the side-
pocket, if needed, and a few ounces in weight only ; also at
such a price that half-a-dozen can be bought and given to
friends at a cost of a novel.
We advise the reader to study the author's preface,
which contains the appreciation — a courtesy often omitted
by authors in general — of the author's obligations to other
astronomers in enabling him the more readily to produce this
excellent little primer, which might well be used as a school
book and by teachers themselves. We heartily recommend
it, and may the healthy vigour of its youth enable it to reach
the maturity of manhood's age.
F. A. B.
CHEMISTRY.
A Treatise on General and Industrial Inorganic
Chemistry. — By Dr. E. Moi.inari. Translated from the
Italian by E.Feilmann, Ph. D., F.I.C. 704 pages. 279 illus-
trations. 3 plates. 10-in. X6|-in.
(J. & A. Churchill. Price 21/- net)
This book is almost monumental in its scope, for it covers
the whole ground of inorganic chemistry, historical, physical,
and especially industrial. In some respects it suffers from
this fulness, and some of the sections show indications of
their severe compression into a single volume of seven hundred
pages.
This criticism, however, does not apply to the description
of manufacturing processes, which, with few exceptions, are
dealt with at length. In fact, the scheme of the book is to
unite the applications of chemical reactions more closely with
the theoretical aspect than is usual in text books of chemistry.
Full details are, therefore, given of the plant used in the
modifications of various industrial processes, and the book
not only gains in interest by this plan, but is also valuable as
a source of reference for the technical chemist and patent agent.
In most instances the descriptions of the manufacturing
processes are up-to-date, but this is not invariably the case.
For example, the account of the artificial mineral water
industry is very meagre and not entirely accurate. A historical
error may also be noted in this connection. It is stated
(p. 228) that " the first scientific factory for mineral waters
was founded on a scientific basis in 1821 by Dr. Struve at
Dresden." This is incorrect ; for as far back as the year 1780
artificial mineral waters were scientifically prepared and sold
by Professor Bergman in Sweden; and in 1790 a factory for
their manufacture was established, also on a scientific basis, by
Paul in Geneva.
Another subject that receives too little attention is the
chemistry of the rare earths, which is only dealt with very
briefly, and in this direction the book would not be a good
guide to anyone in search of the latest information.
An excellent feature is the description of the uses to which
the various chemical products are applied, and the statistics
of the values of the quantities annually manufactured or
exported. Naturally, the chemicals of Italian origin receive
the fullest treatment, and among the subjects discussed in
connection with them is a most interesting account of the
present position of the sulphur industry, and its progress since
the establishment of the State Consortio Italiana to regulate
the supply and distribution of sulphur.
The book is excellently printed and illustrated with good
diagrams, while the translation is well done. It has deservedly
reached its third edition. r A M
GEOLOGY.
The Work of Rain and Rivers. — By T. G. Bonney, LL.D.,
F.R.S. (Cambridge Manuals of Science and Literature.)
144 pages. 19 figures. 6i-in. X 5-in.
(The Cambridge University Press. Price 1/- net.)
To the present generation it seems amazing that the forma-
tion of river-valleys was once ascribed to anything rather than
the rivers which occupy them. Yet, as Professor Bonney
shows in the last chapter of this entertaining little book, the
true explanation of river- valleys is only a recent addition to
scientific knowledge, and the earlier geologists (with the excep-
tion of Hutton and a few others) were content to believe that
the valleys were made for and not by the rivers. Professor
Bonney rightly ascribes to J. B. Jukes the honour of settling
beyond question the modern view of the work of rivers
in excavating their own valleys ; but he perhaps rather
exaggerates the influence of the eccentric Colonel George
Greenwood, and his book " Rain and Rivers." The rest of the
book follows the accepted lines, and while containing little
that is new, describes the work of rain and rivers in a way
that is bound to excite the interest of the reader. The nature
of the treatment may be indicated by the chapter headings —
Carving and Carrying, The Making of Valleys, The Transport
and Deposit of Materials, The History of a River System,
Man's Learning of Nature's Lesson. The author does not
approve, as we learn in a footnote, of the modern and
extremely convenient terminology which we owe to the genius
of Professor William Davis. His illustrations of river-action
and history are largely drawn from the Alps, and in the
absence of sketch-maps are occasionally not very easy to
follow. There is something wrong with the statistics on
page 73, where it is stated that a thousand tons of carbonate
of lime, if re-converted into chalk, would form a block
measuring two feet by three feet at its end and eleven feet
in length. G_ w_ T
Preventable Cancer. A Statistical Research. — By Rot.LO
Russell. 167 pages. 7j-in. X 5,1-in.
(Longmans, Green & Co. Price 4/6 net.)
The above volume well deserves careful study. The writer
is not a medical man, and, therefore, when speaking of the
76
KNOWLEDGE.
February, 1913.
nature of cancer, is wisely content to quote from various
authors whose views agree more or less closely with his own.
Then follow some very valuable and carefully - prepared
statistics regarding the increase of cancer, its geographical
distribution and its relation to trades and occupations, and
lastly come the author's conclusions which are perhaps best
given in his own words, " The malady shows a real and
regular increase in all civilised countries during the last fifty
years." " Apart from exceptional customs it scarcely exists
among peoples and in districts and countries where the diet is
cool, and frugal, without irritating or stimulating adjuncts, the
use of water as the staple drink is of effect in immunity." Of
the various substances taken as foods, the following are
regarded by the author as tending to the production of cancer
" fermented liquors, animal and other proteids in long and
continuous excess, highly salted and toxic foods and drinks,
hot foods and drinks much above blood temperature, and
apparently highly acid drinks, such as sour wine and some
metals or minerals, of which arsenic is an acknowledged
example." A critical examination of the figures quoted by
the author makes it very difficult to arrive at any other
conclusion than that which we have quoted above. The
author is to be warmly congratulated on the very careful
way in which he has collected and arranged his statistics.
S. H.
The Doctor and the People. — -By H. de Carle Woodcock.
312 pages. 7j-in. X5-in.
(Methuen & Co. Price 6/- net.)
In the volume before us we have a series of short essays
on everything that appertains to the work of the general
practitioner, the doctor of the people. The hospitals, contract
practice, the Poor Law, and a host of other subjects, not
excluding the National Insurance Act, are all discussed from
the point of view of the enlightened general practitioner.
" The provincial doctor, and even the Metropolitan, is, like
the French peasant, letting the world's controversies rage
while he attends to a hundred daily duties of his practice.
Sometimes he assists at a tragedy that he cannot prevent,
sometimes at one that he can. He is an easy target for the
caricaturist, but he does not read the caricature ; or if his
attention is arrested when Mr. Bernard Shaw attacks him in
a whirlwind of wit, he remembers that in the last twenty-four
hours he has saved, quite possibly, more than one life. Such
is the man I have wished to portray." Again and again have
we taken up the book, intending to review it, but so full of
interest have its pages been that we have been compelled to
continue reading. Some chapters we have read again and
again, so excellent is the style in which these are written. The
author is no Utopian, but at least some of the faults of our
present system he is unable to pass over. Our Poor Law
comes in for a large share of reproof, and terrible are his tales
of the work of the Poor Law doctors. The infirmaries suffer
little better at his hands. " These Poor Law hospitals have
been and still are under-staffed ; the nurses have not held the
highest rank in the nursing world ; the doctors have in many
cases ceased to be scientific and have become swamped in the
small details of hospital management." The admission of
medical students and the provision of a staff of visiting con-
sultants to these institutions is strongly advocated.
To the doctor and his patient alike we most heartily
recommend this book. c
b. H.
PAINTING IN NORTH ITALY.
A History of Painting in North Italy from the
Fourteenth to the Sixteenth Century. — By T. A. Crowe
and G. B. Cavalcasei.le. Edited by Tancred Borenius.
3 vols. 1339 pages. 207 illustrations. 9-in.X6-in.
(John Murray. Price £3 3s. net.)
The three volumes in which Messrs. Crowe and Cavalcaselle
deal with the history of North Italian painting is the com-
plement of their larger work on the history of painting in Italy,
which has been for many years in course of republication,
and, like it. has been long out of print. Together they form
an invaluable and exhaustive compendium of information on
Italian art, with which no student can dispense. Crowe and
Cavalcaselle pursued their labour of love in the intervals of
important official work, and at a time when photography was
in its infancy, when handbooks were unknown, when frescoes
and paintings now collected in public galleries and museums
were still mouldering in the inaccessible remote churches and
convents for which they had been painted, a prey to damp
and neglect. Those who have read carefully all the republished
volumes can only marvel at the industry, the knowledge, the
insight, which amounted to genius, in this monumental work.
Despite the accumulation of data of various kinds, of lost and
forgotten archives, of recovered paintings, which have come
to light since its first appearance, editors and commentators
of Crowe and Cavalcaselle have astonishingly little to add to
or to detract from their decisions. Oftener, where in the then
state of knowledge they could only conjecture ; subsequent
investigations have confirmed their conclusions; while their
masterly summaries of the relationship of the art of a painter
to his predecessors and successors, and their penetrating
criticism, have remained unsurpassed. The volumes which
deal specially with painting in North Italy begin with the
impetus given to Venetian art by Fabriano and Pisano, and
by the Bellini ; the paintings of the Bellini, their artistic
position and influence, occupy the greater part of the first
volume. The second volume opens with the school of
Squarcione, whose curious career is unique in the history of
painting. A tailor by trade, Squarcione turned his commercial
instincts into the channels of art. Acute enough to observe
that the religious impulse in art was giving place to the classic
revival, he collected models of antiquity, and formed a school
of painting for their study. Artists came to it from far and
near, and Squarcione derived great kudos from exhibiting
their productions under his own name. Among them was the
great Mantegna, whose work, like that of many of the later
Florentines, bears the impress, in something sculpturesque in
its character, of the classic models he had studied. With
Volume III we have reached that most mystic and poetic of
painters, Giorgione. One special value of these volumes is
that the authors have included the artists of many small towns,
such as Vincenza, Ferrara, Friuli and Brescia, minor schools
which still have their place in the history and development of
art.
E.S.G.
PHILOSOPHY.
Modern Problems. — By Sir Oliver Lodge. 320 pages.
8-in.X5-in.
(Methuen & Co. Price 6/- net.)
The modern problems which Sir Oliver Lodge considers,
are chiefly those of philosophy and sociology. Since Professor
William James developed the philosophy of pragmatism, with
its basic idea that there is no other definition of truth than
that " Truth is useful," a great many philosophic doctrines, as
well as theologic speculations and scientific hypotheses have
been examined by this touchstone. It was, in fact, from a
contemplation of the mutable hypotheses of science — mutable
in the sense that theory is useful only as it relates facts and
must continually accommodate itself to newly-discovered ones
— that the basic postulate of pragmatism arose. Sir Oliver
Lodge, who is a philosopher almost before being an investi-
gator, and who at any rate has never separated the two roles,
supplies for the pragmatists several solutions of problems in
scientific paradox which have engaged their attention. For
example, in the essay on " The Nature of Time," he points
out that while it might be plausible to argue that, if we regard
time as made up of discontinuous instants, we can have no real
existence except in the present instant, yet that these
" puzzles about duration and succession, about co-existence
and sequence, are avoided, or greatly minimized, by recognizing
that our direct primary form of apprehension is not either
space or time, but Motion." From time he goes on to argue,
very usefully it seems to us who have wandered rather
confusedly between the opposing battalions of the Pragmatists,
February, 1913.
KNOWLEDGE.
77
the Rationalists and the Intellectualists, that we must have
arrived at our conceptions of the Universe by utilization
and development of notions derived from our primary and
direct sense-perceptions of Motion, of Speed, and of Force.
Other essays deal with the philosophy of M. Bergson ; with
the definition of wealth ; with social reforms, and with one of
Sir Oliver's most practical contributions to the community's
immediate well-being — SmoUe Prevention.
E. S. G.
PHYSICS.
The Principle! : or the First Principles of Natural
Things. To which are added the Minor Principia and
Summary of the Principia. — By Emanuel Swedenborg.
Translated from the Latin by James R. Rendell, B.A., and
Isaiah Tansley, B.A. With an Introduction by Isaiah
Tansley, B.A., and a Foreword by Sir William Barrett,
F.R.S. 2 vols. 1340 pages. 104 figures. 8^-in. X 5i-in.
(The Swedenborg Society. Price 21/- net.)
Swedenborg- is best known, perhaps, by his later philo-
sophical and theological worUs. But during the last few
years an increasing interest has been taken in his earlier
works on natural science, it having become apparent that he
anticipated some of the important discoveries and theories of
modern times in physics and cosmology. This excellent and
carefully prepared translation of Swedenborg's Principia will,
therefore, be welcomed by all physicists and cosmologists who
are interested in the history of science. Swedenborg con-
ceived of nature as the expression of the Divine Will, but
according to him, this Will always operates according to fixed
laws of order and sequence. Consequently, although
Swedenborg, as a philosopher, took a transcendental view of
nature, regarding it as a miracle ; as a worker in science he
treated nature as a machine, and attempted to work out a
complete theory of natural phenomena based on mechanics
and geometry. His position in this respect, is somewhat
similar to the attitude of that particularly clear thinker of the
present time, Dr. C. Lloyd Morgan.
Whenever experimental facts were obtainable, Swedenborg
utilised them. But experimental science was in its merest
infancy in Swedenborg's day. and consequently he was
frequently obliged to argue a priori. This led him, in his
Principia, to make assumptions, which, nowadays, would not
be allowed. Nevertheless, his genius was far in advance of
his time, and enabled him more than once to get at the true
explanation of phenomena. He was the first to put forward
the concept of a vortex-atom. He regarded light as produced
by undulations in the ether (a theory already put forward by
Huygens, but discredited by Newton). He also regarded heat
and electricity as having an etheric origin. His explanation
of the reason of the magnetisation of iron, by stroking with a
magnet, is perfectly correct ; and his words on this point
might, as Sir William Barrett points out in his valuable and
appreciative Foreword, be those of a modern student. More-
over, his explanation of the orgin of the solar system must be
regarded as an anticipation of the theory of Laplace. Indeed,
Swedenborg seems to have been a man of extraordinary
mental abilities, whose works have been too much neglected.
An Appendix containing critical and explanatory notes by
Professor Very adds to the value of the present translation.
H. S. Redgrove.
RADIOACTIVITY.
Radioactive Substances and their Radiations. — By E.
Rutherford, D.Sc, F.R.S. 699 pages. 8}-in.X6-in.
(The Cambridge University Press. Price 15/- net.)
It is eight years ago since Professor Rutherford published
what was rightly regarded as the authoritative work on the
emanations of radioactive substances, and from that volume
many which have been written since are largely derivative.
In 1904 the theory of the disintegration of the atom, of which
Rutherford made use to explain the phenomena of the
expulsion of atoms and electrons, and of rays as yet not
entirely accounted for, was still under discussion. Lord
Kelvin was not entirely convinced ; and there was an alterna-
tive theory, not without advocates, which was that the energy
of radium was first taken in from an external source, and was
than transformed into radioactive energy by a kind of surface
osmosis. Professor Rutherford's answer to this suggestion
was to dissolve a speck of radium bromide in a solution of
radium chloride which was a thousand times the speck of
radium's bulk, and then to show that there was no alteration
in the rate or quality of the radiation such as there should
have been if the radiation had been dependent on external
sources of energy.
One recalls the experiment as something almost archaic,
so soundly now does the disintegration theory seem estab-
lished. But it is of importance to notice the rate at which
confirmation of the theory grew. Confirmation was given to
it by the increasing knowledge of the transformations which
radium and other radioactive substances underwent, because
it was evident that the mechanism of transformation was the
same or similar in succeeding cases, and with the accumu-
lation of instances it became clear that the idea of unstable
atoms disintegrating under the influence of a disturbance to
the units of their atomic systems, was the only one which
would cover all the cases. In 1905 twenty of these trans-
formations in radioactive substances were known. The
number now is thirty-two, and Professor Rutherford remarks
that there is some evidence to show that a few transforma-
tions still remain undetected. They are not easy to find,
because the transformations are so extremely rapid : and in
consequence the lives of the elements produced by them are
extremely short. Radium has a life of respectable pro-
portion, though it is so far below the career enjoyed by its
venerable ancestor Uranium : but the one thousand seven
hundred and sixty years which are the '" half-life of radium,"
are a comparative immortality by the side of the lifetime of
that element derived from the emanation of thorium, whose
life is only fourteen-hundredths of a second, or of the actinium
derivative, the lifetime of which is one five-hundredth of a
second.
These are some of the results of the eight years of investi-
gation conducted in every physical laboratory of the world,
and summarised in what is, in all respects but that of theory,
a new volume. The eight years, however, besides affording
a vast amount of information, have been fecund in new
methods and in new ideas. The most singularly useful of
the new methods is, perhaps, that due to the discovery of ways
of counting single a particles. This has not merely extended
the knowledge of the a particle, but it has been of the
greatest importance in obtaining accurate data for the calcula-
tion of a number of important radioactive quantities and
atomic magnitudes. It must not be forgotten that it is since
1904 that physicists have learnt to weigh the negative
corpuscle.
Again, the discovery of the recoil of radioactive particles
when an a particle has been expelled, has proved to be useful
as a means of separating radioactive substances : it has also
furnished a new kind of corpuscular radiation for study. The
importance of secondary radiations ; the light they throw on a
possible positive particle of electricity ; the nature of gamma
rays and their probable identity with Rbntgen rays — these
are the things which are now of most importance in the study
of radioactivity. To them all, as well as to the influence
which emanations of radioactive substances exert on the
electrical state of the atmosphere, Professor Rutherford gives
exactly the right kind of judgment and consideration. His
new work is one of those which are inevitably and indubitably
standard works : and the only corollary we could have wished
to add to it would be a more extended consideration of
Professor Bragg's theory on the nature of " electric doublets "
and the Rbntgen rays. H s< Kedgrove.
78
KNOWLEDGE.
February, 1913.
YEAR BOOKS.
Who's Who, 1911— 2,22b pages. 83-in. X 5.1-in.
(Adam & Charles Black. Price 15/- net.)
" Who's Who " comes to us this year in an enlarged form,
and contains no less than twenty-five thousand biographies.
Its great usefulness is made thereby still greater, and the
chances of anyone not finding within it what they seek are
considerably lessened. As would be expected, many men of
science are included, and the records of their lives, brief
though they are, make very interesting reading. Some of
them seem to consider that they have no need for recreation,
and probably that is
true of many enthus-
iasts, but others,like the
generality of people,
tell us how they get
relaxation. One well-
known zoologist gives
as his recreations, con-
versation in clubs and
tricycling. An Ameri-
can evolutionist boldly
states that he gets his
recreation in work. A
distinguished German
physicist spends his
spare time in climbing
the Alps, to which pas-
sion he says he has
clung for almost his
whole life. " Who's
Who " should be on
the shelves of every
intellectual person and
in every office of any
importance.
Whitaker's Alman-
ack, 191 J.— By Joseph
Whitaker, F. S. A.
1,036 pages. 7j-in. by
5-in.
(Price 2/6 net.
Paper l/- net.)
Almost everything
that can be said in
praise of "Whitaker"
has been printed in the
many years during
which it has been
before the public. The
valuable astronomical
information which it
contains would entitle it to a notice here, even if on its general
merits it did not claim its annual welcome. To us, perhaps,
its greatest usefulness lies in giving us the names of various
officials who carry on the scientific and educational work of
the Government, and that is but one point among many
thousands which others have come to appreciate.
Whitaker's Peerage, 1913. — 854 pages. 72-in.X 5j-in.
(Price 5/- net.)
With Whitaker's Almanacks comes " Whitaker's Peerage,"
which is of a convenient size, reasonable price, and handy to
use, because it has one alphabetical list of everyone who has
a title or who has gained a decoration.
The International Whitaker, 1913. — 529 pages.
7i-in.X5-in.
(Price 2/- net.)
The " I nternational Whitaker " is a new year book, which gives
information something similar to that of the old " Whitaker "
By the courtesy 0/
Figure 69.
A Sectional Web spanning an open doorway
with regard to our colonies and the various countries of the
world. As may be imagined, it is particularly intended for
English-speaking people, and it contains an interesting bio-
graphical note concerning the originator of " Whitaker's
Almanack," which it is to supplement, but not to supersede.
We anticipate for it a most successful career.
/OOLOGY.
Spiderland, — By R. A. Ellis. 108 pages. Numerous
plates. 73 -in. X 5^-in.
(Cassell & Co. Price 3/6 net).
As would doubtless be judged from its title, this popularly
written book is inten-
ded for young people,
and we may add that
it will fulfil its object.
Its author's claim that
there are few books
dealing with the life of
spiders is a good one ;
occasionally in nature
study volumes a chapter
may be devoted to the
creatures in question,
and the writer of this
notice when a boy found
that they were one of
the things that could
be studied with interest
and advantage in a
town garden.
In " Spiderland " a
very clear description
is given, when dealing
with structure, of the
conformation of the
spinnerets, and not the
least attractive parts of
the book are those
which are concerned
with the weaving of
snares.
Occasionally one
meets with a sentence
which sounds more
effective than accurate:
as, for instance, in the
one which states that
spiders "banquet on the
ruddy drops that warm
the hearts of theirinsect
prey." Moreover "pro-
tective resemblance "
is the proper term to use when speaking of the likeness
of the spider to its natural surroundings. It is difficult to
" mimic " a flower or a twig. The author has been allowed
to make use of the writings of the late Dr. McCook, and the
following incident recorded by him is given : — " An English-
man, being pursued by Red Indians, sought refuge in the
hollow of an old tree. While hiding there he saw a spider
begin to weave her web over the entrance. Within a very
short space of time the orb was completed and the little weaver
took her station in the centre. No sooner had she done so,
than a Red Indian came by. He approached the hollow tree,
tomahawk in hand, but noticing the web with the spider
in the centre, naturally concluded that there was no tenant
there."
There are many excellent illustrations and the volume
altogether forms a valuable addition to a boy's or girl's
collection of " nature books."
W. M. W.
Messrs. Cassell & Comfian
(From (l Spiderland.")
February, 1913.
KNOWLEDGE.
79
Wild Life. — Edited by Douglas English. Volume I,
Number 1. 64 pages. Numerous illustrations. 12|-in. X9|-in.
(The "Wild Life" Publishing Co. Price to subscribers, 17/6
for six months, 30/- for twelve.)
Wild Life is a new illustrated monthly magazine of which
the letterpress is to be based solely on first-hand observation,
and the illustrations are to be from photographs alone. It is
the outcome of the widely-spreading cult of Nature photo-
graphy, and. more immediately, of the exhibition of the work
of the Zoological Photographic Club, held at the offices of the
Zoological Society last summer. The first number now before
us is most excellent, and it is probable that the future ones
will be even better ; for an editor, as he proceeds, becomes
more and more critical with regard to the perfection of the
photographs which he chooses, and the way in which they
are reproduced. Mr. Farren's photographs and account of the
nesting Egrets, which flourish not more than a three-days'
journey from London, are delightful. We reproduce, by per-
mission, one of the photographs taken by Mr. Douglas English
to accompany his remarks on " The Wild Cat" (see Figure 70).
Dr. Francis Ward's observations and pictures illustrating
" Photography under Water " are very interesting, and there
is much good work by other well-known photographers. Two
of Mr. R. B. Lodge's " Eagles" are noteworthy ; the third is
too obviously touched up, and his Griffon Vultures are not
successful. The carrying of the letterpress right across the
wide page gives a certain style to the publication, but the lines
are too long for easy reading. Wild Life marks an epoch
in the modern studv of Nature, and we wish it every success.
W. M. W.
■
a pho'i'gra; k
Figure 70. The Wild Cat.
(From "Wild Life" by the courtesy of the Editor.)
by Douglas English.
NOTICES.
BIRDS IN AVIARIES.— Those who are interested in the
acclimatization of foreign birds wiil find a good deal of
interesting matter in Mr. Wesley T. Page's ' Aviaries, and
Aviary Life," in which many of the birds, with nests which
have been built in this country, are illustrated. It is published
by the Avian Press, Ashbourne.
FORMALIN AS AN INSECTICIDE. — Experiments
have been made at University College, Cork, to determine the
insecticidal power of formaldehyde. Various strengths from
•01 to 2 per cent, were used, but the results, we learn from
The Irish Naturalist, show that any efficacy which formalin
might possess as an insecticide is more than counterbalanced
by its injurious action on the plant.
EGG OF THE GREAT AUK.— Mr. Thomas Parkin con-
tributes to British Birds for January an account of the very
finely marked egg of the Great Auk, which was sold at
Stevens's, on November 21st, 1912, for two hundred and
twenty guineas, to Messrs. Rowland Ward, Ltd. It was the
property of Mr. W. Sheppard, of Bristol, in 1807, and
purchased by Mr. Shirley, of Ettington, about 1820. It was
put up for auction in 1910, when Mr. E. L. N. Armbrecht
bought it for £262 10s.
PAUL RAINEY'S EXPEDITION TO SOUTH
AFRICA. — The most remarkable set of moving pictures
obtained on Mr. Paul Rainey's expedition are now on view
at the Holborn Empire, in London, and cannot fail to interest
anyone who takes the trouble to go and see them. The
naturalist would, of course, be most pleased with the striking
films obtained near a water hole, which show several
rhinoceroses, two giraffes, a family of elephants, numerous
deer, monkeys, and many birds. Sportsmen would appreciate
the hunting of cheetahs and lions by means of dogs, and it
must be added that Mr. Reginald Carrington's descriptive
lecture is most lucid and explanatory.
80
KNOWLEDGE.
February, 1913.
SECOND-HAND INSTRUMENTS.— More than fifteen
hundred pieces of scientific apparatus for sale, or on hire,
are given in Mr. C. Baker's current list of second-hand
instruments. We have often alluded to the usefulness of
these catalogues and commend the present issue to our
readers. On one of the advertisement pages we notice the
announcement of a new one-sixteenth inch oil immersion
objective, the price of which is £6 10s.
PORT ERIN BIOLOGICAL STATION. — Professor
Herdman's Annual Report of the work done at Port Erin
Biological Station is always interesting, and the twenty-sixth
one which has come to hand is particularly valuable because it
contains a number of maps, charts, and plans of Port Erin
Bay and the neighbourhood, prepared for the use of
advanced students or research workers, on which they can
record localities and captures.
BRITISH ASSOCIATION ADDRESSES.— A corres-
pondent signing himself O.B.L. sends us the following note. —
" I see from the Publishers' Circular an announcement to
the effect that Messrs. Longman are publishing 'The only
authorized address of the President of the British Association '
delivered at Dundee. From this are we to assume that the
copies of the address sold by the association to the members
at Dundee, and that the version which appears in the Annual
Report in about a year's time, are unauthorised ? "
HORNIMAN MUSEUM LECTURES.— The following
Saturday afternoon lectures will be given at the Horniman
Museum during February. —
Feb. 1st. — "Tools and Weapons of
the Old Stone Age " Dr. H. S. Harrison
(Curator of the Museum).
,, 8th. — " The Gun-flint Industry
of Brandon : a Sur-
vival of the Stone
Age" ... ... Mr. Edward Lovett
(of the Folk-Lore Society).
„ 15th. — "Japanese Ivories and
Designs" ... Mr. A. R. Wright, F.R.A.I.
„ 22nd. — " The Day's Work of a
Root"
Dr. E. Marion Delf.
HINTS ON PHOTOGRAPHY.— We have received from
Messrs. Charles Zimmermann & Company the "Agfa" hand-
book, which is published by the photographic department of
the Actien-Gesellschaft fiir anilin-fabrikation, Berlin, containing
a number of chapters by well-known English photographers
on such subjects as time development, rodinal for the develop-
ment of gaslight papers, and exposure meters. Messrs.
Zimmermann will send a copy on receipt of a penny
stamp.
EGYPTIAN LEGENDS.— The forthcoming book in Mr.
Murray's " Wisdom of the East " Series is " Ancient Egyptian
Legends," translated by Miss M. A. Murray, the well-known
lecturer on Egyptian Literature, of University College,
London. The author has given a free rendering of the
fascinating legends of the ancient Egyptian Gods, Isis,
Osiris, Horus, Ra, telling of their loves, battles, prayers,
adventures, and sacrifices, which are likely to appeal to
a wide public, while at the same time in her notes on
the subject she has made provision for the more serious
student.
MEDICAL BOOKS.— Messrs. Adam and Charles Black
will, in future, publish the following medical books which were
formerly issued by Mr. James Currie, Edinburgh. — " Hand-
book of Medical Treatment; A Guide to Therapeutics for
Students and Practitioners, with an Appendix on Diet," by
James Burnet, M.A., M.D., M.R.C.P.E. ; " Manual of Medical
Jurisprudence, Toxicology, and Public Health," by W. G.
Aitchison Robertson, M.D., D.Sc, F.R.C.P.E., F.R.S.E. ;
Second edition, with thirty-nine illustrations, crown octavo.
"The Pocket Clinical Guide," by James Burnet, M.A., M.D.,
M.R.C.P.E.; "The Pocket Prescriber." by James Burnet,
M.A., M.D.,' M.R.C.P.E.
A PHILATELIC MICROSCOPE. —We have received
from Mr. Harold Cheavin a description of the inexpensive
microscope which he has designed for philatelic workers, and
recently exhibited before the Royal Microscopical Society.
The microscope will prove useful in examining small details
which are of great importance to stamp collectors, and by a
simple adjustment, water-marks may be made out as well as
the texture of the paper used. It is also very easy to fit the
microscope into the front of a camera from which the lens
has been removed, and so to take any photo-micrographs
that may be required. The instrument is made by Messrs.
Watson & Sons, but all communications should be addressed
to Mr. Cheavin, Somerset Road, Huddersfield.
THE PRESERVATION OF FLORA AND FAUNA.—
It will be remembered that at the Dundee meeting of the
British Association in September last the President of the
Zoological Section, Dr. P. Chalmers Mitchell, F.R.S., took as
the subject of his address : " The Preservation of Fauna."
At the close of the meeting the General Committee passed on
to the Council, for consideration, a resolution, which has now
been adopted, in the following terms: — "That the British
Association for the Advancement of Science deplores the
rapid destruction of fauna and flora throughout the world, and
regards it as an urgent duty that steps should be taken, by the
formation of suitably-placed reserves or otherwise, to secure
the preservation of examples of all species of animals and
plants, irrespective of their economic or sporting value, except
in cases where it has been clearly proved that the preservation
of particular organisms, even in restricted numbers and places,
is a menace to human welfare.
THE ALCHEMICAL SOCIETY.— The first general
meeting of the Alchemical Society, which has been formed for
the study of the works and theories of the Alchemists in their
various aspects, was held on Friday evening, January 10th,
at the International Club, Regent Street, W. The Hon.
President of the Society is Professor John Ferguson, M.A.,
LL.D., F.I.C., F.C.S., and amongst other notable members we
may mention Mr. H. Stanley Redgrove, B.Sc, F.C.S., Mr.
Arthur Edward Waite, Mr. W. Gorn Old, Mr. Philip S.
Wellby, M.A., and Madame Isabelle de Steiger. At the
meeting a lecture was delivered by Mr. H. Stanley
Redgrove, B.Sc, F.C.S. (whose " Alchemy, Ancient and
Modern," is well known to students), on " The Origin of
Alchemy." The lecturer pointed out that the alchemists in
the past had been too harshly condemned as half charlatans,
half fools. As he said, although some of them were of this
nature, many of the alchemists were men of fine intellect and
inspired in their studies with noble ideals ; and he suggested
that, in spite of the fact that their assumptions led them into
many fantastic errors, they did seem to grasp certain funda-
mental facts concerning the universe of very great importance.
But, even supposing their theories to be utterly wrong, it was
still necessary to account for the fact that they gained almost
universal credit. Why, asked the lecturer, did the alchemists
adopt such views concerning natural phenomena ? Here, he
said, was a proper subject for scientific investigation. His
reply, which he illustrated at considerable length, was that the
alchemists started with two assumptions: (1) the truth of
mystical theology, especially the doctrine of the soul's
regeneration ; and (2) the truth of the statement that natural
objects are the symbols of spiritual verities. They, thus,
reasoning a priori, attempted to explain natural phenomena
by the application to them, by analogy, of the principles of
mystical theology.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
MARCH, 1913.
ELECTRIC WAVES.
By W. D. EGGAR, M.A.
Middle-aged people, like the writer, may still be
found who will answer, when asked the meaning of
the word electron, that it is the Greek name for
amber. This is admittedly
true, but it will probably be
unsatisfactory to the ques-
tioner, who will be expecting
much more up-to-date infor-
mation. Modern text-books,
if we may include anything
published within the last
twenty years as modern, will
suggest many different defin-
itions of the sub-atomic
bodies on which Dr. Johnstone
Stoney, with a somewhat mis-
placed generosity, bestowed
the title of electron. They
are centres of strain in the ether, cathode rays,
/3-particles, bricks of which atoms are built, ends of
Faraday tubes. The mass
of an electron is given as
6- 1 X 10 ~2M grammes, and
its radius as 10 ~13 centi-
metres, and some persons
with a taste for figures
may feel some small satisfaction in this information.
It is still open to anybody to form any conception
that he may find possible
of the ultimate structure
of space ; but certain
facts about the aether are
becoming part of our com-
mon life, and are even a
subject of inquiry for a
Parliamentary Com-
mittee. Whether we regard an electron as a whirl-
pool in a continuous medium, or as the terminus of
Figure 71
Figure 72.
a Faraday tube in an aether of which the structure
is fibrous, there seems to be no question that move-
ments of electrons are accompanied by a disturb-
ance of the adjacent medium,
and that this disturbance
travels along the medium,
whatever its structure, with
a velocity of 3X1010 centi-
metres, or approximately one
hundred and eighty-six
thousand miles per second.
Wireless telegraphy is
accomplished by a succession
of electric, or electro-mag-
netic disturbances, propagated
as waves through space. It is
remarkable that Britain had
furnished the theory of these
waves before their existence was demonstrated
practically on the Continent. Sir J. J. Thomson,
in " The Encyclopaedia
B r i t a n n i c a " ( X 1 1 h
Edition), points out that
Lord Kelvin, in 1853,
proved from theory that
the discharge of a Leyden
jar must be oscillatory. Feddersen proved it by
experiment. Clerk Maxwell proved that, on his
theory, electro -magnetic
waves must travel through
space with the velocity
of light. Hertz, in 1887,
demonstrated the exist-
ence of these waves, em-
ploying as the source of
disturbance an oscillatory
He found that such a discharge
small sparks between the ends
spark-discharge,
would produce
81
82
KNOWLEDGE.
March, 1913.
of
a copper
wire bent nearly into a circle.
It has been said already that the discharge of a
Leyden jar is oscillatory. Lodge devised a method
of obtaining a persistent oscillatory discharge, and of
tuning a receiver for it. The transmitter consists of
Figure 74.
Transmitter at the Lyngby Station.
a Leyden jar A. (Figure 71) with a bent wire nearly
connecting the outer and inner coatings, which
are themselves connected to the terminals of an
induction coil. When the coil is working, a per-
sistent series of oscillatory sparks crosses the air-gap
G. The receiver is another Leyden jar B, also with
a bent wire, with an air-gap H, the planes of the
two bent wires being parallel to each other and at
right angles to the line joining the centres of the jars.
The sliding piece C can be adjusted so that when
A is at work sparks pass across the gap H. A very
slight displacement of C causes the sparks to cease.
Figure 75.
Receiver at the Lyngby Station.
Now, although such a transmitter and receiver
can be made very perfectly /'/) tune with each other,
such a receiver is not sufficiently sensitive for long-
distance work. Electric waves produce various
other effects which can be employed to detect their
presence. Branly discovered that the resistance
between loose metallic contacts is diminished when
electric waves fall on them, and the detectors made
on this principle are known as Coherers. Rutherford
found that a bundle of iron wires magnetized to
saturation was demagnetized by the alternating cur-
rents caused by electric waves. Marconi's magnetic
detector employs this discovery in the form of an
endless flexible iron wire, made to move round and
round by clockwork under permanent magnet poles ;
the changes in the magnetization caused by the
electric waves induce currents in a telephone receiver.
Such detectors can be tuned to show maxima effects
for waves of particular lengths, but the effects do
not cease completely for other wave lengths.
It has been said that the electric waves generated
by the discharge of a Leyden jar may be compared
to the sound waves produced by a pistol-shot. Per-
haps it would be fairer to compare them to the
waves produced by a drum-tap. There is at least a
very rapid damping of the waves, i.e., a rapid falling
off in their intensity, although the wave length, /' e.,
the distance between successive crests, may remain
the same. (See Figure 75.) The waves of a sound of
a drum would produce in the groove of a gramo-
phone record hills and valleys similar to those shown
in Figure 75. The record of a tuning fork, however,
would be more like Figure 72. So would the record
of an organ pipe, so long as a stream of air is being
driven across its embouchure. Analogies are some-
times misleading ; but in seeking analogies between
different kinds of waves we are not likely to go far
wrong if we bear in mind the main characteristics of
all wave motion and the main specific peculiarities
of each kind.
In all wave motion we find the following charac-
teristics, among others :—
(i) The disturbance takes time to travel from one
place to another. Electric waves travel
one hundred and eighty-six thousand miles
per second, waves of sound in air about
one thousand one hundred feet per second.
(ii) A medium to transmit the disturbance is
necessary. The medium for electric waves
is generally spoken of as the aether ; sound
usually travels to our ears in air.
(iii) When waves follow each other at regular
intervals and fall on some system capable of
being disturbed by them, then if that system
has a natural period of vibration correspond-
ing to the period of the waves, it will be
caused to vibrate in sympathy with them.
This phenomenon is known as resonance,
and numerous familiar instances of it might
be recalled.
(iv) The velocity of the waves, the wave length,
and the frequency are connected by the
equation V=NL. For instance, let us take
a tuning fork giving two hundred andseventy-
five vibrations per second ; the waves travel
March, 1913.
KNOWLEDGE.
83
with a velocity of one thousand one hundred
feet per second ; therefore, the space between
each wave and the next will be four feet.
Again, suppose an electric oscillator sending
out one million waves per second. The
wave length must be three hundred metres,
since the velocity of propagation is JXlO10
centimetres per second.
The frequency of an ordinary alternating current
is far too low to
produce
waves
JV
of
sufficient energy for
use in wireless tele-
graphy. In 1899
Duddell discovered
the following phe-
nomenon : — When a
condenser of suitable
capacity is connected
through a self-induc-
tion coil in parallel
with an electric arc
which is being fed
by direct current, the
arc will, under certain
conditions, become
musical. At the
same time there is
set up in the self-
induction an alterna-
ting current, having
the same rate of
vibration as the note
produced by the arc.
In other words, part
of the direct current
is transformed into
an alternating current
of constant ampli-
tude, the energy ab-
sorbed being supplied
by the direct cur-
rent.
A very close anal-
ogy to Duddell's
musical arc may be
found in a flue organ
pipe. Here the note
is produced by the vibrations of the air column in the
pipe, whose dimensions determine the pitch of the
note. These vibrations would die away, or be
damped, very rapidly but for the energy supplied by
the continuous current of air blown across the
embouchure of the pipe. This air current is directed
against a sharp edge, and must pass either inside or
outside it, thus creating either a compression or a
rarefaction at the end of the pipe. The natural
frequency of the pipe causes the air current to be
turned alternately inwards and outwards, and the
note is maintained, the air current supplying the
energy and paying the piper, the organ pipe calling
the tune.
Fio'jt a photograph
A Tv
By this method Duddell obtained a high rate of
alternation : that is to say, up to thirty or forty thou-
sand oscillations per second. Even this rate is too low
for wireless telegraphy, and the energy far too feeble.
In 1903, however, Professor Yaldemar Poulsen, of
Copenhagen, succeeded in obtaining a much higher
rate of oscillation by surrounding the arc with an
atmosphere containing hydrogen. Hydrogen, with
its high atomic velocity, possesses great thermal and
electrical conductiv-
ity, and no doubt
its cooling influence
makes it possible to
use higher power.
Poulsen further dis-
covered that a strong
magnetic field placed
transversely to the
arc had the effect of
giving a definite shape
to the arc and thus
making the oscilla-
tions more constant,
as well as making it
possible to increase
the potential differ-
ence greatly in pro-
portion to the length
of the arc. By these
two devices Poulsen
has obtained alterna-
tions as rapid as one
million per second.
It is claimed for
the Poulsen-Pedersen
system of wireless
telegraphy that it is
capable of being
tuned with greater
precision than any
spark system. If a
tuning fork in vibra-
tion is held over an
open piano, only one
ivw. DuddtiL wire will show reson-
ance. On the other
hand a pistol shot
will make all the
wires vibrate at the same time.
Another claim is that a speed comparable with
that of submarine cables can be attained by the
Poulsen automatic transmitter (Figure 74;. With
this, as in the Wheatstone instrument, the message
to be sent is represented by a series of holes punched
in a continuous paper strip, those on one side of
the central line representing dots, and those on the
other side dashes. This strip is fed into a rotating
contact maker, and by means of the holes the con-
tinuous waves of the arc are cut up into lengths,
short for the dots and long for the dashes. The
aerial wire at the receiving station picks up these
wave trains, and transmits them to a crystal rectifier
Figure 76.
3 Kilowatt Generator.
84
KNOWLEDGE.
March, 1913.
consisting of particles of galena and tellurium in
contact, which permits the current to pass, in one
direction only, through a " string " galvanometer.
A shadow of the string is projected on;to a moving
strip of sensitive paper, which passes on into develop-
The system has been tried successfully between
Lyngby, in Denmark, and Cullercoats, at the mouth
of the Tyne. a distance of six hundred miles.
Whether it will work as well between Ireland and
North America remains to be seen.
Figure 77. Poulsen M
ing and fixing baths, so that a permanent record of
the vibrations of the string is obtained, similar
to that of Lord Kelvin's siphon recorder, which
is shown in Figure 75, at the bottom of page 82.
California (U.S.A.)
The merits of the various rival systems are still
sub judice. The brief sketch of one of them which
we have given may be helpful to some who are
interested in following the evidence.
RESEARCH DEFENCE SOCIETY.
We have received the following appeal from the Officers of
the Research Defence Society and have much pleasure in
commending it to the notice of our readers.
To the Editors of " Knowledge."
Sirs, — It is said that the fifth year, in the life of any
Society, is the critical period of its fortunes. The Research
Defence Society was founded on January 27th, 1908. To all
who are interested — and who is not ? — in medical research,
we beg you to let us say that the Society has its hands full of
work, and only wants more money to do more work. Much
has already been done, by lectures and by distribution of
literature, to bring home to people the truth about experiments
on animals in this country, and the great value of them, not
only to mankind, but also to the animal world. The expenses
of our Society are heavy ; but the good results of our work
are extended far and wide. We have lately opened a Bureau
and Exhibition at 171, Piccadilly (opposite Burlington House).
We are exhibiting pictures, portraits, charts, anaesthetics and
inhalers, germs in pure culture, tsetse flies and mosquitoes,
and so forth. This little exhibition, every day and all day
long, displays to " the man in the street " the facts of the case.
We are the only Society which is doing work of this kind ;
but, of course, it cannot be done without money. Our record
for the last four years gives us the right to hope for a great
increase of our Membership, and of our funds, in the coming
year" DAVID GILL, President.
F. M. SANDWITH, Hon. Treasurer.
STEPHEN PAGET, Hon. Secretary.
21, Ladbroke Square, W.
THE INFLUENCE OF AGE ON THE VITALITY AND
CHEMICAL COMPOSITION OF THE WHEAT BERRY.
By R. WHYMPER.
fact that
end to all
there
liviriE
The knowledge that the vitality of a living thing
decreases with the passage of time is so imprinted
in the human mind that all
our life is spent, consciously or
unconsciously, in prolonging
the end which must come or
in preparation against that
time.
But the
must be an ^..^ w ***.
things does not restrain but
rather stimulates both our efforts
in unravelling the mystery which
surrounds the very existence of
life and our imagination in
regarding a thing which has
possessed life even beyond the
span of years allotted to man.
A tortoise of four hundred
years is an object of respect, a
giant oak of some one hundred
and fifty years is venerable,
and both by reason of their
vitality command greater regard than a lifeless rock
which has existed more or less
of constant appearance and
consistency since the world
began.
With the passing of life,
decay of the material sets in
eventually : sooner if the organic
matter is readily decomposable
and under suitable conditions :
later if the matter is more
resistant or under conditions
which tend to prevent the action
of moisture, air and bacteria
from having full play.
Thus animal remains rapidly
decompose when exposed to
air under ordinary conditions,
though, as in the case of
bodies carefully dried or spec-
ially treated with antiseptics,
they may remain in a state
Figure 78.
Mummy Wheat, longitudinal section
this
of preservation for a considerable period of time.*
Vegetable matter containing much cellulose is
obviously less liable to rapid
decay than that containing
easily fermentable components
such as cooked starch and
sugar ; this can be readily seen
in such cases as the bread and
cake found in the tombs of the
ancient Egyptians and which
are now composed of little else
than the husks of wheat and
other cellular tissue.
It was the custom of the
ancient Egyptians to provide
their mummied dead with
articles of use and personal
property as well as with food
such as bread, meat, wine,
cakes and wheat, as means of
refreshment during their trying
journey to the world " beyond
the sunset " and it is owing to
religious custom that we owe many of our
most treasured ancient Egyptian
relics. It is to be hoped that
the food placed with the dead
was found sufficiently sustaining
to last over the long period of
time which elapsed before the
wandering soul again found rest
in the bod}-, and which, if
Herodotus is to be believed, was
about three thousand years, or
at least that it was never failing
in quantity like the " widow's
cruse."
The quality of the food stuff,
however, after the same lapse
of time, leaves a good deal to
be desired, though the wheat
with which the present paper is
chiefly concerned is remarkable
for the few changes that have
taken place within the berry.
* It may be of interest at this point to mention that I have in my possession a raw beef steak placed in " vacuo " in glass in
1889 and which to all appearance is in a remarkably good state of preservation. My uncle, the late Mr. Edward Whymper,
and Mr. Hicks conducted a number of experiments with "vacua" in that year, chiefly in connection with the standardisation
of aneroid barometers.
The beef steak in question was one of their many experiments and my uncle always displayed great interest in this
unique object, which was found at his death in his bedroom at Teddington, where I remember it many years previously.
The following observation is attached to the glass vessel containing the meat, and, apart from the appearance of a few
rose clustered crystals which have separated out, it is the only indication that the piece of steak is not fresh.
"April 30th, 1904. — This piece of Rump Steak was sealed up in " vacuo" on January 7th, 1889. Originally it occupied
about four-fifths of the length of the tube. It has constantly shrunk, but it is only in the last few months that I have
noticed the appearance of the fungoidal growth."
The meat now occupies less than one-tenth of the volume of the tube and the supposed fungoidal growth is in reality a
crop of crystals.
85
Figure 79.
Mummy Wheat, transverse section.
86
KNOWLEDGE.
March, 1913.
Figure 80.
Wheat of the year 1852, longitudinal section.
Figure 81.
Wheat of the vear 1852, transverse section.
The most stable of the articles of food found in the
ancient Egyptian tombs is wheat, and it would
certainly add fuel to the lire of imagination, if from
the wheat grains of a date somewhere about the
time of the supremacy of Joseph in Egypt could be
grown a crop of corn whose life had lain dormant
for so many centuries.
In cases where authentic Mummy Wheat has been
used, all attempts to secure germination have failed,
though it will not be without interest briefly to
review some of the failures and supposed successes
in growing wheat and other seeds which were
known to be of great antiquity, and to examine the
possibility of the existence of life after so many ages.
The conditions which regulate the speed of
germination can only be said to be indirectly
connected with vitality since, in many cases, whilst
germination is the exhibition of vitality, the causes
which retard germination are purely physical
characteristics of the seed.
Thus, certain seeds
with thick impervious
integuments, such as
clover, which under
favourable circum-
stances germinate with-
in one or two weeks,
may be found quite
sound and dry inter-
nally though kept con-
tinuously wet on the
outside for many years.
In such cases it seems
that a scratch is suffi-
cient to cause almost
immediate germination
by allowing the mois-
ture to penetrate the
protective outer coating.
The appearance of
strange plants in newly-
turned earth removed
from excavations, has
been attributed to this
power in seeds of lying
dormant till, by the fric-
tion with the earth, the
tough integument has
been entered and the
moisture allowed to
reach the embryo.
The older the seed
the lower is the prob-
able vitality of that
kind, and it is, of course,
a well-known fact that
the older seed, with the
life still in it, requires
greater coaxing to bring
about germination, and
that the plant resulting
from it is more weakly in its growth.
In considering wheat, therefore, say three thousand
years old, whilst it is certainly not impossible to
imagine that it may, if kept for that time under
ideal conditions, still be capable of germination,
it is hardly to be expected that it should show signs
of life, seeing that the conditions under which it has
passed so many years in the Egyptian tombs, though
good, were still such as would allow decay to set in,
and a certain amount of air and damp to assist the
decomposition.
The thickness and impenetrability of the outer
husk or covering is the chief governing factor for the
duration of vitality in seeds under equal conditions
of environment.
According to the most recent researches* the
power of germination of barley and wheat is but little
affected during the first five years, but thereaftera rapid
loss of vitality occurs and proceeds at an increasing
rate till, in the tenth vear,
no living seeds remain.
Figure 82.
Wheat of the year 1853, longitudinal section.
Figure 83.
Wheat of the year 1853, transverse section.
W. Carruthers, Roy. Agric. Soc, 1911, p. 168.
March, 1913.
KNOWLEDGE.
87
The seeds under dis-
cussion were kept in
paper bags in a drawer
of the laboratory, and,
therefore, may be pre-
sumed to have been
subjected to fairly con-
stantconditionsof mois-
ture and temperature.
Oats kept under
similar conditions
maintained their vital-
ity for from five to seven
years longer and, taken
in conjunction with
previous observations,
may be said to supply
the key to the results
of the long list of
experiments made by
Carruthers. " The difference between wheat and
barley on the one hand, and oats on the other, is the
greater protection afforded to the embryo of the oats
by the fact that in its case the glumes, which fall
off as chaff in the wheat and barley, remain attached
to the seed."
The cause which decides whether germination or
death shall result in the embryo of a seed is the
balance between heat and moisture.
Heat is, perhaps, the greater factor, if it is possible
to speak so of two essentials, in deciding germination,
whilst moisture may be said to govern vitality.
By this is meant that whilst moisture without
heat, or heat without moisture, is incapable of produc-
Figure 86.
Rivet Wheat, longitudinal section.
Figure 87.
Rivet Wheat, transverse section.
about 1 J0°F without life becoming extinct.
It would perhaps be more correct to say that in
the case of germination, the balance between heat
and moisture is finer than when the death of the
embrvo within the seed alone has to be considered,
when, though the loss of moisture beyond a certain
point means death, the temperature to which the
seed is subjected may be varied within very wide
limits without appreciable loss of vitality.
In the case of genuine Mummy Wheat, that is
wheat found in the tombs of Egyptian mummies of
known antiquity, heat existed without the necessary
moisture to bring about germination, and the gradual
desiccation of the berries reduced the moisture con-
ing germination, yet the heat optimum applied to a tent of the embryo below that with which life within
seed with a minimum of moisture, is more likely to the seed remained possible.
produce germination than a maximum of moisture The same cause brought about the death of the
present with a minimum of heat. In the other case, seeds examined by Carruthers, who states that it
moisture must be present in the embryo plant if life was no " chemical alteration produced by tern-
is to be retained, though air-dried seeds have been perature, but the steadv loss of moisture going on
exposed for some days to a temperature very far continually at ordinary air temperature."
below freezing point, or, again, to an upper limit of After life is extinct the changes which take
place within the wheat
grain are more chem-
ical than bacteriological
in the case of Mummy
Wheat at any rate, for
the presence of such
powerful antiseptics as
bitumen and essential
oils (both of which are
very apparent in the
smell of the Egyptian
Mummy Wheat here
examined) is sufficient
to prevent the action
of moulds or bacteria.
The exact nature of
these changes will be
discussed more fully in
Figure 85. a later section.
Wheat of the year 1854, transverse section. The Mummy Wheat
Figure 84.
Wheat of the year 1854, longitudinal section.
88
KNOWLEDGE.
March. 1913.
examined was found in a tomb at Deir-el-Bahari of
an estimated date 1500 B.C., and, assuming that the
harvest season of that date was a fair one, the berries
probably contained some 12 per cent, of moisture
when placed beside the dead. At the time of analysis
about three thousand four hundred years later, it
contained 10-69 per cent, of
moisture and, in itspassageacross
the sea from the very warm
climate of Egypt to the compara-
tively moist atmosphere of *s
England, it certainly picked up
at least the odd 0-69 per cent.
The loss of the 2 per cent,
of moisture and its vitality- are
the only outstanding features
which distinguish this most
ancient wheat from that of the
last season's harvest. The in-
crease in acidity and loss of
gluten strength, though pro-
nounced, are comparatively in-
significant and are due to the
two main causes.
In a previous paper* the
writer has observed that under
good conditions of germination
about 35 per cent, of its weight of water is absorbed
by the wheat berry, and it is conceivable that with
a constant temperature such as is found in the
subterranean tombs of the ancient Egyptians life
might have been perpetuated within the berries
by the continual existence of,
say, another ten parts of water
in every one hundred parts of
the wheat, over that which was
actually present, an additional
quantity which would not have
encouraged germination.
Under the existing heat and
humidity conditions of the tomb
the tendency of the wheat
was to impart its moisture to
the surrounding air, and thus
the moisture content of the
wheat was reduced below the
minimum which was capable
of supporting life for even
beyond ten years, and the
grains may be assumed to
have lain for some three
thousand four hundred years
without the power of repro-
ducing their kind.
It is reasonable, therefore, that the wheats of such
recent dates as 1852, 1853 and 1854 should show
but little variation in chemical composition over their
kind of last year's harvest. Indeed there are not
Figure 88.
Flour obtained from the Mummv Wheat.
Figure 89.
Flour obtained from Rivet Wheat.
sufficient chemical differences between all the
samples of wheat analysed to show that the loss of
that potent factor, Life, has taken place, nor even do
the analyses show more divergent results than would
be obtained from modern wheats of different
varieties.
The experiments of Car-
ruthers, already referred to,
» have for ever buried the alluring
possibility of genuine Mummy
Wheat reproducing its kind or
even of a ten-year-old wheat
from presuming to emulate the
efforts of a new born ; but it is
probable that under the correct
conditions which it is hoped
will be found when the result of
the experiments on hand are
completed, and which, after all,
are nothing more than rational,
the vitality of wheat will be
extended and the natural pro-
cess of decay arrested till it is
conceivable that dormant life
may be prolonged beyond even
the three thousand years which
have passed over the head of
the Mummy Wheat now under examination and
of its accompanying and honoured dead, who by
this time is, according to Egyptian belief, again
the proud possessor of a soul, though probably
exhibited under a glass case to the vulgar gaze
of an inquisitive and un-
believing public.
Previous Attempts to
Germinate Seeds of
Ancient Origin.
It has already been pointed
out that in different seeds the
duration of vitality is very
variable. Thus it is quite
well authenticated that the
seeds of the Nelumbo (water
lily) have sprouted after having
been kept dry in a herbarium
or museum for one hundred
and fifty years, whilst on
the other hand the seeds of
wheat have been shown by
Carruthers in a paper already
mentioned to have lost their
vitality at the end of ten years when kept dry under
normal conditions. Even among one class, such as
the cereals, the duration of vitality in the seeds is
very variable, as will be seen by Table 16 taken
from Carruthers' paper : —
■'VII. Intcrnat, Cong. App. Client., 1909, and Milling, March 18th, 1911.
March. 1913.
KNOWLEDGE.
Table 16. Percentage of Seed Germinated each Year.
89
Seed.
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
Barley ...
White Wheat ...
Red Wheat
White Oats
Black Oats
99
100
99
100
97
99
97
98
99
97
98
92
95
99
96
95
94
88
99
94
90
?
94
98
90
77
88
80
99
98
25
75
79
99
92
?
?
55
95
94
19
29
51
97
95
—
69
88
57
76
49
68
12
34
0
32
2
—
Nor can this be taken as the last word on the
subject, for the preservation of vitality is, of course,
dependent upon a number of factors, the chief of
which are : —
(a) The character of the season and the ripeness
of the seed when harvested.
(b) The percentage of moisture in the seed.
(c) The place of storage.
The varying results of other experimenters on the
duration of vitality among cereals confirm this state-
ment, and to quote two instances : — Loudet, who
made trials in 1856-7 with wheat of the years
1853-1856 inclusive, obtained the followingresults: —
Wheat of 1853, per cent of seeds germinated 0
>> >> lOjT, ,, ,, ,, ,, ,, 01
>> ?? ±C30Z>? ?? ,, ,, ,, ,, / O
,, ,, 1856, ,, ,, ,, ,, ,, 74
whilst Haberlandt, on the other hand, obtained
results more comparable with Carruthers, thus: —
Table 17.
Percentage of
Seeds Germinated in 1861
from the Years —
1850
1851
1854
1855
1857
1858
1859
1860
Wheat ...
0
o
8
4
73
60
84
96
Rye
0
0
0
0
0
0
48
100
Barley ...
0
0
24
0
48
Si
92
89
Oats
60
■>
56
48
72
32
80
96
Maize ...
0
?
76
56
?
77
100
97
Dealing with Mummy Wheat, which should be
very much older than those just discussed, there
have been many experimenters who are said to have
succeeded in bringing about germination. Of these
the most notorious is the Count Sternberg,* who (it
is said) received the grains of wheat from a trust-
worthy traveller, being assured that they were taken
from a sarcophagus. Two of these grains are
supposed to have germinated, and though the
majority of well-informed people must realize that
there was some imposture, probably on the part of
the Arabs, the belief in the existence of vitality in
Mummy Wheat is still strong, owing to the publica-
tion of Count Sternberg's paper, and the constant
repetition of his statement in non-scientific journals,
that, even up to the present time, a very large
number of people who do not study the probabilities
is prepared to combat any statement to the
contrary.
When the array of experimenters with Mummy
Wheat, or wheat of even more recent date, is
reviewed, and when it is realised that in almost
every case of wheat over ten years old, germination
does not result, the probability of Count Sternberg's
success can be at once dismissed.
Vilmorin, Dietrich! and many others besides
the present writer have attempted to grow genuine
Mummy Wheat and always with the same negative
results. Soaking in oil, as recommended by Count
Sternberg, and nearly even' means reputed to favour
germination have been employed but without success,
and the same methods applied to the wheat grains of
the years 1852, 1853, and 1854, were equally
unsuccessful. After proper exposure to moisture,
the space that should be occupied by the germ has
been found to be filled with a slimy putrefying liquid
which was quickly covered by a crop of mould.
It is useless to describe the methods applied to
the grains in order to induce germination, and it is
proposed to enter at once upon the results of the
chemical and microscopical examination to which
they were subjected, and to draw from them such
conclusions as may be of scientific and commercial
value.
Experimental Results.
The five wheats examined were as follow : —
Mummy Wheat, circ. 1500 B.C. The grains of
this sample were dark rusty red in colour and fairly
plump though the end containing the germ was
shrivelled and wrinkled. Twenty-seven grains of an
average sample of this wheat weighed one gramme
(See Figures 78 and 79).
On crushing for chemical and microscopical
examination the grains rapidly disintegrated and
formed a very fine powder, so that it was with
difficulty that a loss of the very light portions was
prevented. The fine powder immediately after
crushing was very irritating to the nostrils and
smelt strongly of bitumen.
The grains are believed to be of Emmer wheat
from the appearance amongst the sample of what
seems to be a complete head of the wheat bearing
only two grains.
Wheats of 1852, 1853, 1854, were all samples
of White Wheat, that of the first two years
showing medium plump grains (thirty-four to the
Count Sternberg in the Journal, Flora, 1835, Page 4.
f Dietrich, Hoff. Jahr. 1862-3, Page 77,
90
KNOWLEDGE.
March, 1913.
gramme). The last year's sample was particularly
plump and numbered twenty-two grains to the
gramme. (See Figures 80-85).
Wheat of 1911 was a sample of Rivet Wheat
grown in Huntingdonshire of plump grains
which numbered twenty to the gramme. (See
Figures 86 and 87).
On treating the whole grain flour (crushed in the
laboratory) with water, that from the Mummy
Wheat produced a thin paste without any strength
of dough whatever. The apparent stickiness and
lack of elasticity led the writer to believe that a
considerable amount of soluble dextrin and possibly
sugar would be found. This assumption proved to
be unfounded on analysis.
The flours from the wheats of 1852, 1853 and 1854
showed plenty of elasticity on doughing with water,
and had not suffered apparentlv in " strength " through
deterioration of their gluten by long storage.
The lack of a sufficiency of the sample of Mummy
Wheat prevented any investigation into the state of
its nitrogenous compounds, which, though still
present in considerable proportions, had completely
lost the physical characteristics of wheat gluten.
Microscopical Examination.
In a previous paper, by means of transparent
sections taken through the wheat berry, the writer
was able to show the changes and direction of change
taking place in the grain during germination. It
was hoped that sections of the wheats here under
examination, taken in a similar manner, would reveal
certain structural changes which might be expected
to have taken place during the passage of so many
years. Examination, however, shows that the actual
structure of the germ remains unchanged, and that
only the coalescence of the minute cells has resulted.
In the wheats of 1852, 1853, and 1854, the germ
remains unaltered in appearance.
Closer examination of the endosperm of the
Mummy Wheat reveals the decomposition of the
cementing material which binds the bundles of
starch together, and, consequently, the extreme
friability of the wheat grains when crushed, and the
lack of adhesiveness of the resulting flour when
doughed, are accounted for. The actual starch grains
are not affected in any way, and it may be assumed,
therefore, that no diastase had penetrated into the
endosperm as would occur on incipient germination.
As will be seen from the acidity figures of the
ground berries there is no great increase in sourness
in the w^heat grains up to fifty years, but a very pro-
nounced increase in the more ancient Mummy
Wheat.
This fact is interesting in the light of Professor
Bell's experiments with stored flours, made in 1907,
and other experiments made in America in the two
following years.
The general indication of these tests showed that
the increase of acidity was more pronounced in the
case of low-grade than high-grade flours, and was
due chiefly to the action of acid-producing bacteria
which have ready access to stored flour.
It was further proved that dampness was the
prime factor which favoured the production of
acidity, whilst temperature was of little or no
account.
In normally air-dried wheats, sufficient moisture
does not exist to produce acidity rapidly, and the
protective covering of the husk is thick enough to
stay for a considerable period the action of aerobic
acid-producing bacteria.
As soon as the husk is capable of being penetrated
by air, either from the slow growth of moulds and
smaller fungi on the exterior of the grain or from
chemical oxidation, the growth of the acid-producing
bacteria within the berry is favoured.
It is of further interest to note that increase of
acidity is accompanied by reduction of the gluten
strength, a fact which has been noted by Wood and
others who found that even N/1.000 solutions of
hydrochloric acid and varying dilutions of other
acids such as phosphoric, oxalic, acetic, lactic, citric
and tartaric, were capable of producing degradation
of the gluten and a corresponding reduction in the
" strength" of the dough.
The most prominent feature of the microscopical
examination of the flours produced from the wheats
under discussion was the appearance of long, sharp-
pointed angular pieces, into which the oldest wheat
fell when crushed. (See Figure 88).
The shape of the particles is entirely different
from those produced from normal wheat, or from
the wheats up to fifty years of age. (See Figure 89).
This is accounted for by the decomposition of the
binding proteid matter and by the cleavage which
has taken place when the grain is crushed along the
lines of the proteid matter which binds the bundles
of starch granules, rather than along the non-proteid
divisions which separate the starch-proteid groupings.
It is without doubt correct that in normally aged
and dried wheat the first cleavage is along the lines
of the parenchymatous cellulose, by means of which
the endosperm is divided up into groups of starch
granules embedded in gluten. These groups are, as
a rule, angular and also four-sided, and are readily
distinguishable from the sharp-pointed and tapering
pieces into which the endosperm breaks up when
the Mummy Wheat is crushed.
(To be continued.)
THE PROBLEM OF THE MOON'S ORIGIN
By B. G. HARRISON, F.R.A.S., F.R.G.S.
{Continued from page 74).
The system consists of seven principal planets,
besides our earth, in various stages of evolution, and
rotating at different speeds, hut the conditions
affecting each one are so diverse from those of our
own globe that no satisfactory analogy can be drawn.
It is true that the rotations of Jupiter and Saturn are
exceedingly rapid, but this is just what we should
expect if the theory of planetary formation previously
outlined is correct, since the larger planet would have
a larger moment of momentum than would be derived
from its extra mass alone, owing to the more rapid
circulation of particles caused by greater gravitative
force in its vortex during the planet's evolution.
Another objection to the fission theory of the
Earth is the difficulty of understanding how it would
be possible for a concrete mass the size of the Moon,
torn away from the Earth by rapidity of rotation, to
hold together under the disruptive strain imposed by
the mutual attraction of the two bodies when in close
proximity.
Thus it seems, so far as we are aware, that the
origin of the lunar terrestrial system by capture
offers none of the difficulties that we have to contend
with in the fission theory, and if we accept the
nebular hypothesis outlined earlier in this article,
would seem the most natural and concordant way of
accounting for the present position of the Moon.
Nevertheless, weighty though the objections are
to the theory of the Moon ever having formed part of
the Earth, our satellite offers a very remarkable
piece of evidence in favour of this supposition.*
This evidence consists in the action of tidal friction.
The manner in which the Moon raises tides by
differential attraction is too well known to require
any explanation here. If no tidal friction existed,
high water would always be on those parts of the
Earth's surface directly under the Moon. As, how-
ever, water is not perfectly frictionless, the rotation of
our globe carries these aqueous bulges to a point some-
what in advance of the Moon's orbital position, and
they consequently act as a brake on terrestrial rota-
tion. Since it is impossible for one body to retard
another without a corresponding acceleration in its
own motion, it follows that the energy lost by the
Earth must be transmitted to the Moon. This has
the effect of increasing its orbital force, and under
the influence of centrifugal action driving it further
away from us. As, however, this force is only tan-
gential, and the action of recession involves motion
against the more powerful pull of direct attraction,
the actual orbital velocity is decreased, and the addi-
tional energy transmitted becomes entirely potential.
Thus we see our day and lunar month both slowly
increasing in length, although not at the same rate.
Conversely, in earlier times both must have been
shorter. If this decrease had been a measurable
quantity in historic times, we should be able to detect
it from the record of the early eclipses ; for although
it is necessary to have the utmost accuracy in the
majority of astronomical observations if they are to
be of any value, in this case the knowledge of the
locality in which the eclipse was observed would to
a great extent compensate for the lack of precision
in the record of its actual time of occurrence. Yet
it appears that there is no conclusive information to
be obtained from this source, and its absence makes
us feel certain that retardation of rotation must now
be an exceedingly slow process. Nevertheless, this
is no proof of its non-existence, and since the loss of
energy by friction varies inversely as the sixth power
of the distance, any reduction of the Moon's orbit
would involve a vast increase in the retardation of
our axial rotation.
It is possible, therefore, to imagine a time when
our day was only half its present length, and to
calculate, by deducting the energy which the Earth
has since that time transmitted to the Moon, what
the length of the month would have been at the
same period. At the present time the rate of increase
of the day is more rapid than that of the month, and,
consequently, if we work backwards, we find the
month shortening less rapidly than the day. This
relative progression continues until a time is reached
when there were twenty-nine days to the month,
instead of 27-3 as at present. This is a maximum,
and it has been mathematically demonstrated that
there could never have been more than this number
of days during one revolution of the Moon. Remote
though this period must actually have been, it
is yet comparatively recent when we consider
the vast time necessary for the entire process
required by this theory, and may be regarded
as a crisis in our satellite's history. Before this
epoch the month must have decreased more
quickly than the day, and, still travelling back-
wards, we can trace the Moon in the course of ages
moving ever faster in a huge spiral path. Rapidly,
now, though the acceleration of the Earth's rotation
must have proceeded, the Moon continued to gain
upon it until eventually both were revolving together,
:' The following theory is due to the researches of the late Sir George Darwin, F.R.S., from whose papers on the subject
the figures and general particulars have been obtained.
91
92
KNOWLEDGE.
March, 1913.
the Moon close to the Earth, and each permanently
presenting the same face to the other. Now,
when this period was reached, both day and
month would have occupied some time between
three and five hours. It has been previously
mentioned that the speed of rotation necessary
to render the Earth unstable, owing to centri-
fugal force, would be about two and three-quarter
hours, so we have now arrived at an epoch when our
planet would barely be able to hold together. It is
assumed that the earth must at this time have been,
if not actually in a molten condition, at least
considerably more plastic than it is at present.
Even now the tidal action of the Sun is shown by
the difference between spring and neap tides, and the
more plastic the condition of the Earth the more
effective would this be. It is thought probable that
when our globe was rotating at this speed the forced
period of the tide would be in close agreement with
its free period, which would have the effect of increas-
ing the height of the solar tides sufficiently to render
it quite possible for the Earth to break up under the
combined strain, and thus give birth to the Moon.
The principal difficulty which confronts us is our
inability to understand how it would be possible for
the latter to hold together under the strain imposed
upon it by the attraction of the Earth, and it is
suggested that the Moon was thrown off as a flock
of meteorites until it reached a sufficient distance to
allow it to condense into one bod}-. Nevertheless,
this suggestion is not very satisfactory, since the
meteorites would necessarily be at varying distances
from the Earth, and so would be travelling at
different velocities to preserve their equilibrium.
This would have the. effect of scattering them all
round their orbit, and so tend to nullify their
power of creating tidal friction. However, if this
difficulty is put aside, the facts brought out by
Sir G. H. Darwin's analysis are really remarkable,
and it seems more than difficult to ascribe this
wonderful coincidence to chance, especially as
the eccentricity of the Moon's orbit and the
obliquity of the ecliptic also harmonise with this
theory. If the Moon originated in any other way
the chances are enormously against the mutual
reaction of the two bodies being exactly as we find
them. To make this clearer let us assume the
present position of the Moon and the length of our
day to be unknown, but that we had evidence of our
satellite having originated in the way just described;
then, by calculating the force of tidal action, we
should find that this would be just sufficient to have
driven a body of the Moon's dimensions to a distance
of two hundred and thirty-nine thousand miles, and
reduced the rotation of the earth to its present period
of twenty-three hours fifty-six minutes.
It is interesting to pursue this theory further, and
try to penetrate our planet's future in the same way
as we have endeavoured to trace its past history.
For, if no lunar energy is being lost by motion
against resistance, the length of the day must be
increasing more rapidly than that of the month.
Consequently, we foresee a time when our day is twice
its present length, and the month containing only
eighteen of these days. Mathematical analysis
enables us to penetrate still further, until we reach a
period when the day and month are again equal, but
instead of being only four hours long, they extend to
about fifty of our present days. There is also this
difference that, whereas in the former case the Moon
was revolving in a state of unstable equilibrium, in
the latter it is dynamically stable. The time
required before the two bodies can reach this con-
dition is so vast that it passes human comprehension,
and it is more than likely that some third factor will
have interposed before the requisite period has
elapsed. However, if the system is still behaving in
its present orderly fashion, it is possible to forecast
the final act in this drama. We have reached a
time when the Earth and Moon are revolving as
if bound together by steel bars, and consequently
causing no tidal friction in each other.
Nevertheless, the action of the Sun will continue
to affect the Earth, and the latter will consequently
commence to rotate more slowly than the Moon
revolves. This will cause a recurrence of tidal
friction between the two bodies, but with this
difference, that now the protuberance caused by the
Moon will be behind it instead of in front. This
will naturally have the opposite effect on the lunar
orbit and will gradually draw the satellite back in
ever decreasing spirals, accelerating the Earth's
rotation in the process, until it finally returns to the
surface of the latter. This time however there will
be no chance of the Moon's rebirth, as the earth will
have lost so much energy owing to solar friction
that even in the event of the Moon having
encountered no resistance in its celestial journey,
and so being able to return the whole of the energy
transmitted to it by the Earth, the latter's rate of
rotation will still be slower than at its birth.
There is one more point to be considered, namely
the movement of Phobos, the inner satellite of Mars.
The motion of this satellite has frequently been
advanced as a proof of the former rapid rotation of
its planet, and so indirectly of the Earth.
It was discovered in 1877 by Professor Hall, and
was found to revolve round its primary in seven hours
thirty-nine minutes at a distance of less than four
thousand miles from its surface. As the Martian
day exceeds our own by more than half an hour this
system appears to be absolutely unique, and its
discovery electrified the whole astronomical world.
It has been suggested, therefore, that this system
has been evolved by fission, and has already reached
its final stage with its day longer than its month ;
the rotation of Mars having been reduced to its
present period by solar tidal friction. It is unlikely,
however, that this can be the case, since the com-
parative weakness of the solar tides on the planet,
and the exceedingly small orbital momentum of the
satellite, present very considerable difficulties to the
supposition. Moreover, the phenomenon can quite
well be accounted for by the theory of capture in a
March, 1913.
KNOWLEDGE.
93
resisting medium, since owing to its minute size a
proportion of its momentum would be more easily lost,
and it might thus have been brought to its present
position close to the planet by revolving against
resistance. This suggestion gains weight from the
fact that there are known to be over six hundred
similar bodies to the two Martian satellites, revolving
between that planet and Jupiter, and it seems quite
likely that two of these asteroids may at some time
have come within the sphere of the planet's
influence and so have attained their present
positions.
Apropos of these satellites, it is interesting to dwell
for a moment on the remarkable verification of
prophecy brought to light by their discovery. At the
time when " Gulliver's Travels " was written a good
deal of ridicule had been cast upon contemporary
astronomical research, and for purposes of satire
Dean Swift caused Gulliver to relate how, in the
island of Laputa, astronomers had discovered two
satellites to Mars, one of which revolved around him
in ten and the other in twenty-one and a half hours.
Forty years ago such a phenomenon would
have been considered quite impossible and only a
flight of the wildest imagination, and when it is
considered that the laws of chance would be almost
infinity to one against the fulfilment of the prophecy
it renders its realisation all the more remarkable.
We will now briefly recapitulate the arguments for
both hypotheses of lunar origin. The whole subject
turns on the question of a resisting medium. If this
still exists it would invalidate the calculations of the
Moon's motion previously described, and would
render the probability of its having been captured
almost certain. This theory, indeed, appears to
have no very great drawbacks attached to its
acceptance, and, according to the supposed origin
of the solar system, to be most concordant with it.
Moreover, there is an outstanding inequality in the
movement of the Moon which up to the present has
defied the utmost efforts of astronomers to assign to
anv known cause, but which might be accounted for
by the effects of orbital motion against resistance.
Supporters of the fission theory, however, have to
contend with many very real difficulties, amongst
them to account for the Earth ever having had the
necessary rotational velocity, and even if this is
conceded, the difficulty of understanding how lunar
disruption could be prevented until the Moon
attained to a sufficient distance to revolve in
safety. On the other hand there is the wonder-
ful evidence in its favour just detailed and
which, if it is a coincidence, must be regarded
as one of the most extraordinary in the annals
of astronomy. It must also be remembered that
the ability of tidal friction to retard rotation is
an established fact, as shown by the Moon's own
rotation, the only doubtful factor being the time
required to produce any effect.
Our satellite would gain an additional interest if
the capture theory is ever proved to be correct, since
there seems to be a greater fascination in scrutinising
a world having an entirely different origin from our
own, than in merely looking upon a fragment of our
earth. Let us hope that some day the mystery may
be cleared up, and that we may know more concern-
ing the past history of our companion and nearest
neighbour in the cosmos.
CORRESPONDENCE.
AN "IDEAL" MUSEUM AND ITS GUIDE.
To the Editors of " Knowledge."
Sirs, — The " Provincial Curator," in his contribution to
" Knowledge " of January, does an unintentional injustice to
the Trustees and Curator of the London Museum. The
" Guide to Kensington Palace " is, apparently, a reprint of a
former edition in which have been included some notes on the
London Museum by the author, but these notes have no
authority from, and were never submitted to, or revised bv,
those responsible for the London Museum and its arrange-
ment. Your contributor has, perhaps, been misled by this
" guide " into thinking that the series of objects are not
chronologically arranged, but this is a mistake so far as the
rather limited arrangement of the cases in their present
temporary home will permit.
If your contributor would call again at the London Museum
and ask for the Curator, or one of his assistants, he would
have much pleasure in explaining to him the motive and
system of arrangement and in receiving from him any
suggestions for their improvement.
GUY FRANCIS LAKING, M.V.O., F.S.A.,
Keeper and Secretary.
The London Museum,
Kensington Palace.
[Our Contributor " A Provincial Curator " did say (see
" Knowledge" for January, page 16) that the Keeper and
Secretary of the London Museum did not write the Guide,
and now we learn that it was never even submitted to him.
On the face of it, this behaviour seems to be foolish and dis-
courteous as well as detrimental to the best interests both of
the museum and of the author of the Guide, who, we think,
should come forward and give some explanation. — Eds.J
THE FOURTH DIMENSION.
To the Editors of " Knowledge."
Sirs, — In reply to Mr. H. Stanley Redgrove's letter in the
February issue of " Knowledge," I may say that it is not
necessary for me to see his book, nor for him to state in
detail his argument for the real existence of the fourth
and other dimensions. What he has already stated is quite
enough, namely, that his argument is that the existence of one
dimension implies that of a second, a second that of a third,
a third that of a fourth, and so on. I have pointed out that
experience — direct perception of some kind — is the only
possible basis of our knowledge of what exists, and that this
experience gives us the law that where there is one dimension
there must be three, but that it gives us absolutely nothing
else — nothing whatever to support an argument that the
existence of one dimension implies that of a second, and so
on' ..... JOHN JOHNSTON.
Hendon, N.W. j j
THE RECENT ERUPTIONS OF THE ASAMA-YAMA
(JAPAN).
By CHARLES DAVISON, Sc.D., F.G.S.
The eruption of the Usu-san in 1910, of which an
account is given in " KNOWLEDGE " for May, 1912,
was by no means of unusual violence, but was
interesting from the extraordinary rise of a new
mountain more than six hundred feet in height,
with which the volcanic operations were closely
connected. The Usu-san is situated in the northern
island of Hokkaido. Some four hundred and fifty
miles to the south-south-west of the Usu-san, near
the centre of the main island of Japan, is another
volcano, larger in size and much more violent and
devastating in its outbursts. The Asama-yama is
well known in Japan as the most active of all its
volcanoes, and as the scene of an eruption which
ranks as one of the greatest yet known to us. This
took place in 1783, and, as is usually the case, was
followed by a prolonged period of quiescence, which
at last seems to be drawing to a close. Numerous
explosions during the last few years, with a marked
increase of frequency in 1911, tremors and local
earthquakes in large numbers, and a gradual rise in
the floor and the crater, these are all premonitory
symptoms of a coming period of violent eruption, and
possibly of disaster, at some epoch which may be close
at hand, but can hardly be delayed for many years.
The Japanese Government is fortunately alive to
the danger that awaits them. By the timelv pre-
cautions of the police in the summer of 1910, the
eruption of the Usu-san was attended by no loss of
From a photograph of a model.
Figure 90.
The Volcano, Asama-yama.
life. Very different was the fate of the dwellers on
and around the Taal Volcano in Luzon in January,
1911. Here, the early signs of the coming eruption
were neglected, no attempts were made to remove
the inhabitants, with the result that eleven hundred
Figure 91.
The eruption of Asama-yama, May 8th, 1911.
lives were lost in a single night. A watch on the
Asama-yama has already been set. On its south-
western slope, a seismological observatory has been
erected, every throb of the volcano is being recorded,
and, under the guidance of Professor Omori, the
able director of the Seismological Institute in Tokyo,
the observers have learned to distinguish between
the tremors resulting from the volcanic explosions
and those which are unattended by visible efforts.
Professor Omori has recently made three ascents of
the mountain and has studied the detonations which
have accompanied the explosions and the areas
within which the ashes have been deposited. The
results of his enquiries are contained in a valuable
memoir,* of which a brief summary is given in the
following pages.
The position of the Asama-yama is indicated by
the small triangle in Figures 92 and 9.3. It rises
from a plateau-region to a height of eight thousand
one hundred feet above sea-level. As the height of
its base is three thousand nine hundred feet on the
north, and three thousand six hundred feet on the
south side, the mountain proper is still more lofty
than the present cone of Vesuvius. The crater is
nearly four hundred feet in depth and about a
quarter of a mile in diameter. The form of the
mountain is shown in Figure 90, which is repro-
duced from a photograph of a model of the volcano,
and in Figure 91, which represents the eruption
that took place on May 8th, 1911. From Figure
90 it is evident that the present crater is surrounded
on the west side (that is, to the left in the figure) by
the remains of the wall of an old crater once about
a mile in diameter.
The eruptions and earthquakes of the Asama-yama: Bulletin of the Imperial Earthquake Investigation Committee (Tokyo),
Vol. VI, 1912, pages 1-147.
94
March, 1913.
KNOWLEDGE.
95
The earliest known eruptions of the Asama-yama
occurred in the years 685 and 1108. For this
period of its history the chronicle is obviously
incomplete. With the year 1527, the eruptions
were renewed, and at the same time the record
becomes less imperfect. The eruptions occurred in
groups separated by intervals of repose. From
1527 to 1532 there were three eruptions, from 1596
to 1605 four, from 1644 to 1669 twenty, from 1704
to 1733 sixteen, from 1754 to 1783 five, and from
1803 to 1889 there were nine eruptions.
Of these fifty-nine eruptions, the greatest was that
which occurred in 1783, the year of the great
Calabrian earthquakes. This eruption, which lasted
altogether for eighty-eight days, began on May 9th.
For some time it consisted mainly of loud detona-
tions, occasionally accompanied by strong explosions.
But these were by no means continuous, there being
intervals of quiet, one of which lasted for nearly
three weeks. On June 28th, the explosions became
more violent. A month later, ashes fell in Yedo
(now Tokyo, eighty-five miles distant), where the
people, not knowing the cause, wondered why houses
and doors were shaken while the ground remained
quiet. On August 2nd, the violence of the
explosions reached its maximum, large quantities of
red-hot stones and sand were projected from the
crater. On the 4th, the rain of ashes was so dense
that, even in distant towns, lanterns were used
during the daytime in the streets. The next day,
the eruption attained its climax. In the morning,
after many violent explosions, a huge mass of molten
lava and hot mud broke through the north wall of
the crater and flowed rapidly down the northern
flank of the volcano. This lava, after the lapse of
more than a century, is still fresh in appearance ;
there are few signs of weathering, no vegetation
covers it, and the rock still preserves the fantastic
shapes into which it was thrown at the time. The
total volume of this lava is about one-fourteenth of
a cubic mile, or thirty times that of the present
crater of the Asama-yama.
The lava-stream, however, stopped short of the
villages, and, therefore, caused no loss of life or
property. The great torrent of volcanic mud was
more destructive. Descending with a velocity,
which at first was not less than sixty miles an hour,
it swept down the ravines and overwhelmed the
villages along its course, the loss of life rising as
high as eighty per cent, of their inhabitants, and
amounting altogether to that of one thousand one
hundred and sixty-two persons.
Professor Omori estimates that the district covered
by the ashes is about one hundred and forty miles
in length, sixty-two miles in width, and not less than
four hundred and twenty-five square miles in area.
As the layer of ashes was five or six inches deep at
a distance of thirty miles, diminishing to one inch
at Tokyo, the total volume of the ashes ejected,
quite apart from that of the lava and volcanic mud,
must have amounted to one-sixth of a cubic mile, or
at least sixty times the volume of the present crater.
The disastrous effects of this eruption are con-
nected by Professor Omori with the long period of
quiescence which preceded it. For fifty years
previously, the calm was broken only by a few small
explosions. During the last two or three years of
this period, smoke entirely ceased to issue from the
crater, the floor of which was gradually raised almost
to the level of the crater rim. It was due to the
shallowness of the crater in its final stage that the
immense mass of lava and volcanic mud broke
through the containing wall and flooded the
surrounding country.
For more than a century after this great outburst
the Asama-yama remained almost undisturbed. In
1803, there were three slight eruptions, followed by
others in the years 1815, 1866, 1869, 1875, 1879,
and 1889, altogether nine eruptions, none of much
account. Since the latter year, however, they have
greatly increased in frequency. In 1894, six
eruptions took place : in 1899, four ; in 1900, seven ;
in 1901, six; in 1902-1907, six more; in 1908, five;
in 1909, seven : and in 1910, ten. In the following
year, 1911, there were no fewer than forty eruptions,
all but three within the first four months of the year.
In these estimates, minor detonations and explosions
are omitted. Of the sixty-two eruptions during the
four years 1908-1911, there were four of considerable
strength, namely, those of May 31st and December
7th, 1909, December 2nd, 1910, and May 8th, 1911.
The appearance of the mountain on the last of these
occasions is shown in Figure 91. The characteristic
features of these eruptions will be referred to later.
After the eruption of 1783, the crater of the
Asama-yama was probably very deep and its diameter
less than at present. The first attempt to measure
its depth was made by Professor Milne in 1887. A
rope was stretched across the crater. On this a
pulley was run out with another rope that could be
lowered vertically, supplied with thermometers
at the end. When these had been lowered
seven hundred and thirty-five feet, thermometers
and rope were burnt, showing that the base of the
crater had been reached. In June, 1911, Professor
Omori made another attempt to sound the crater.
On this occasion, but little smoke issued from the
floor of the crater, and it was possible to see when it
was reached by the heavy weight lowered from a
part of the crater rim where the wall was vertical.
The depth was found to be about three hundred and
fifty feet, and this result was confirmed by measure-
ments made with a theodolite. Thus, in twenty-four
years, the floor of the crater has risen about three
hundred and eighty feet, so that, after the lapse of
another such period, if the rate of elevation should
continue uniform, the floor will be brought up level
with the margin of the crater.
During the first two months of 1911, seismographic
observations were made at a temporary station at
Ashino-taira,on the south-west flank of the mountain,
at a height of six thousand three hundred feet above
sea-level. From January 9th to February 28th,
thirty-nine earthquakes were registered. All of
96
KNOWLEDGE.
March, 1913.
them were extremely slight, only six being sensible
without instrumental aid. According to Professor
Omori, they belong to two types of movement. In
one, the shock consists only of minute quick
vibrations ; in the other, it begins with slow move-
ments, mingled after a few seconds with quick
vibrations. The shocks of the first tvpe originate at
a depth of two or three miles below the base of the
volcano ; the vibrations resemble those of ordinary
small local earthquakes, and they are probably due
to the formation of fissures caused by the under-
ground expansive force. The earthquakes of the
second type were invariably the results of volcanic
explosions. They began with a preliminary tremor
lasting about two and a half seconds, which Professor
Omori regards as due to the disturbances occurring
just before the actual explosion, such as the formation
or extension of an underground crack. The slow
vibrations, which follow the tremor, are probably of
" the nature of a bodily oscillation and due to the
first bulging up and the consequent outward forcing
of the mountain mass at the moment of the
explosion."
The detailed study of the eruptions of the last
few years has led Professor Omori to some interesting
conclusions. Among the most valuable are those
which relate to the propagation of the detonations
resulting from the more important explosions. These
have been heard at places on the east coast at a
distance as great as one hundred and eighty miles '
from the volcano, and no doubt would have been
In most cases, the area is of the form indicated by
the lightly shaded portion in Figure 92, which repre-
sents the region throughout which the sound of the
Figure 92.
The sound of the eruption of Asama-yama on December 7th, 1909,
was heard on the lightly-shaded area, ashes fell on the darkly-
shaded region.
heard farther if there had been land in this direction.
There are some curious anomalies in the forms of
the areas over which the detonations were audible.
Figure 93.
The shaded portions show the two areas in which the sound of the
eruption of Asama-yama was heard on December 25th, 1910.
eruption of December 7th, 1909, was heard. In
Tokyo (eighty-five miles from the volcano), the
detonation was loud and like that caused by a powder
explosion, shaking the houses strongly, although
there was no movement of the ground. The sound
was heard at a distance of one hundred and ten
miles to the south, and one hundred and seventy
miles towards the north-east. Towards the west,
however, the sound-area extended but a short dis-
tance, for the detonation was inaudible at places
only fifteen miles to the west, and twenty-five miles
to the north-west of the mountain. The darkly-
shaded area represents that within which ashes were
precipitated. It is a lens-like zone, about one
hundred and twenty miles in length, extending from
the Asama-yama in a direction a little south of east.
The arrows show the direction of the surface wind
at the time of the eruption. In some cases, this
agrees roughly with the principal direction in which
sound and ashes were carried ; in others, it is almost
at right angles to this direction. The ashes, more-
over, travelled at the rate of about fifty miles an
hour, while the velocity of the surface wind was
generally less than twelve miles an hour. It will be
noticed, also, that the area of ash-precipation is
roughly symmetrical with respect to the sound-area.
It is, therefore, clear that the sound and ashes were
carried by the upper winds, which appear to have a
fairly uniform direction for the greater part of the
year between east-north-east and east-south-east,
tending as a rule in the latter direction. The height
March, 1913.
KNOWLEDGE.
97
of the carrying currents Professor Omori estimates
at about five or six miles, this being the height
generally reached by the smoke-column during the
explosions of the Asama-yama.
In two cases, the form of the sound-area is still
more remarkable, for it consists of two detached
portions. The shaded areas in Figure 93, represent
these portions for the eruption of December 25th,
1910. One portion includes the Asama-yama near
its western margin, the other lies about fifty or sixty
miles to the west. It will be noticed that the direc-
tion of the surface-wind was north-west in the
eastern portion, and south-west in part of the other,
so that there is no connection between the form of
the sound-area and the direction of the surface-wind.
Here, again, the anomalous form of the area must
therefore be connected in some way with the trend
of the upper winds.
A somewhat similar anomaly was observed in the
audibility of the minute-guns which were fired from
battleships lined at Spithead, when the body of her
late Majesty Queen Victoria was borne from Cowes
to Portsmouth. At places in the immediate
neighbourhood of Spithead, and as far as fifty miles
from it, the guns were almost or quite inaudible.
From sixty to eighty or ninety miles they were
clearly heard, so clearly that at a distance of eighty-
four miles, labourers in the fields put down their
spades and listened. Beyond ninety miles, records
were less numerous, but one came from near Wood-
bridge, in Suffolk, at a distance of one hundred and
thirty-nine miles, the regularity of the booms of the
minute-guns allowing no doubt as to the observation.*
In the neighbourhood of Spithead and Portsmouth,
the wind at the time was from the west or north-
west, or " offshore " ; at the great distances at which
the sound was heard the wind was southerly. Since
the velocity of the wind increases, as a rule, with the
height above the ground, it follows that, in the
direction from which the wind is coming the sound-
rays are bent upwards, and pass over the heads of
observers at a moderate distance. In the opposite
direction, they are bent downwards, so that sound-
rays which started upwards at a moderate angle are
brought down again to observers at a considerable
distance. Thus, the sound-rays were first of all
refracted by contrary winds over the heads of
observers between ten and fifty miles, and were after-
wards brought down by favourable upper currents so
that the reports were clearly audible from sixty to
more than a hundred miles from Spithead. It is
probable that a similar explanation may be given of
the two detached portions of the sound-area in the
case of the explosions of the Asama-yama.
'On the audibility of the minute-guns fired at Spithead on February 1st [1901] :
Pages 124-125.
Knowledge," Volume XXIV, 1901,
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.K.A.S.
THE OCCULTATION OF THE STAR MAYER 588
BY JUPITER'S THIRD SATELLITE, GANYMEDE,
1911, AUGUST 13TH. — This very rare phenomenon was
predicted by Herr Banachiewicz, and observed at several
stations in South America, Professor Ristenpart having cir-
culated requests to observers with a view to deducing the
dimensions of Ganymede. Thirty-two had volunteered to
help, who were spread over thirty-seven degrees of latitude,
from Arequipa, S. 16°, to Punta Arenas, S. 53°. Several
observers noted that the disappearance and reappearance
were sharply defined, and could be accurately timed. The
time intervals give chords of the disc of Ganymede in various
latitudes, and the surprising fact emerges that it must be
considerably larger than was hitherto supposed. The observa-
tions are best satisfied by an elliptical outline, with equatorial
radius two thousand three hundred and thirty-one miles, polar
radius two thousand one hundred and thirty-one miles.
Dr. Ristenpart does not, however, attach great weight to the
ellipticity. Ganymede would appear to be as large as Mars,
whereas former estimates made it only equal to Mercury.
One puzzle that the new result affords is the very low density
that it implies. The mass of Ganymede is one thirty-ninth of
the Earth, or one quarter of Mars, so if its size is equal to
Mars its density is only one quarter as great, or, roughly, the
density of water. It is true that the density of Saturn is still
less, 0-7 of water, but the visible globe of Saturn is believed
to be largely vaporous, which is unlikely to be the case with
Ganymede.
THE SPECTROSCOPIC BINARY 9CAMELO-
PARDALIS. — Several observers have noted abnormal
behaviour of the calcium lines in the case of spectroscopic
binaries. For example, Hartmann in the case of S Orionis,
Daniel, Schlesinger, Duncan and Slipherin the case of p Scorpii,
find that the H and K lines of calcium do not share in the
large displacement of the other lines, though they have
probably a small displacement of their own. The suggested
explanation is that the calcium vapour is not in the stars, but
surrounds them as a cloud. Mr. O. J. Lee, at Professor
Frost's suggestion, selected 9 Camelop. as a suitable star
for further investigation of this question (Astrophysical
Journal, January). Its declination is 60° North, and it
culminates at midnight in December, so that very long series
of photographs can be taken. Further, the H, K lines are
strong and well defined. He deduces that the period of
oscillation of the calcium lines is the same as that of the
other lines viz., eight days, but the amount of oscillation less.
He concludes that the calcium vapour forms an ellipsoidal
sheath round the principal star, and that the spectroscopically
effective regions are near the zero velocity points. He
deduces for the joint mass of the system only one four-
hundredth of that of the Sun, or two and a half times that of
Jupiter. This seems an improbably small mass for so distant
a body (its parallax is given as "-026, implying a distance of
one hundred and twenty light years), but the author admits
that some of his assumptions are tentative. In any case, the
existence of external calcium clouds in the case of several
spectroscopic binaries has been rendered highly probable.
A MEASURE OF SOLAR RADIATION FROM FREE
BALLOONS. — The same publication contains an account by
Professor Very of an interesting research : the service that
ii
98
KNOWLEDGE.
March, 1913.
tree balloons have rendered to meteorology in giving records
of temperature, and so on, at heights inaccessible to man.
They have now been used to carry a Crova actinograph, and
so obtain a measure of solar radiation in a region where
atmospheric absorption is greatly diminished. He gives the
following determinations of the solar constant in calories per
square centimetre per minute at different heights : —
1-5 calories at sea-level (winter).
2-00 „ at 4,420 metres (Keeler, Mount Whitney).
2-86 ,, in the isothermal layer at 13,700 metres.
He concludes that the true value is 3-5 when there is no
atmospheric absorption.
It is considered by some authorities that the solar constant
may itself vary by quite appreciable amounts, independently
of the action of our atmosphere. Professor Abbott suggested
simultaneous observations at distant stations to test this. If
they frequently varied together, the cause would probably be
in the sun itself, not in our atmosphere. I believe that such
a comparison is now being carried out between stations in
Africa and North America.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
STRENGTH OF TENDRILS.— It has long been known
that after a tendril has grasped a support it becomes much
stronger and produces increased hard tissue; but the details
have not hitherto been worked out satisfactorily. In an
interesting paper, Brush (Bot. Gaz., June, 1912) states that
passion-flower tendrils exposed to tension, and having also
formed contact with a support, had a much higher breaking
strength (over one thousand grammes) as compared with
tendrils in contact only (six hundred and fifty grammes) and
free tendrils (one hundred and ninety grammes). Tension
increases strength of tendrils sometimes by as much as fifty
per cent, in the middle third of its length. By radial pressure,
obtained by means of a mercury column in a rubber tube
enclosed by the tendril, an increased breaking strength was
obtained (nine hundred and ninety as compared with seven
hundred and thirty grammes). The breaking strength of the
tendrils was found to be increased by contact, pressure, and
tension. As regards the internal structure it was found that
the wood cells are increased both in number and thickness as
the result of contact, and that the walls of the pith cells are
thickened in consequence of tension. Just how contact,
tension, and pressure act as stimuli it is difficult to say, but it
is probably by bringing about increased hydrostatic pressure.
LUMINOUS BACTERIA AND FUNGI.— Professor H.
Molisch has revised and enlarged his well-known work on
luminosity in plants (" Leuchtende Pflanzen " ; Gustav
Fischer, Jena, M. 7.50). Since the publication of the first
edition, eight years ago, various writers, notably Professor
Molisch himself, have contributed to the knowledge of
luminous phenomena in plants. Many of the cases of so-called
luminosity in plants are due merely to reflection of light which
is brought to a focus by lens-shaped cells, or are brought
about by iridescence or by the presence of fluorescent
substances ; but real phosphorescence — the emission of light
when the plant is placed in total darkness — is found in certain
bacteria and fungi. By isolating the bacteria which cause
the phosphorescence of meat and fish (Bacterium phos-
plioreum, Bacillus phosphoreus, and so on), and cultivating
them in nutrient jelly in tubes and flasks, Molisch obtained a
" bacterial lamp " with which he obtained some excellent
photographs, some of which are reproduced as illustrations in
his memoir. This " living lantern " can be used for a
photographic dark-room or as a night light, since the light is
strong enough to enable one to read a watch or to make out
large print quite readily. The light is steady and lasts for
several weeks, its intensity being about one candle-power per
thousand square yards of the gelatine plate culture. It
appears probable that the phosphorescence of these bacteria
is due to the production by the bacterial cells of a phosphorus-
containing organic compound (" photogen ") of a proteid or
phosphatid nature, which in the presence of oxygen and water
undergoes slow oxidation — probably by means of an oxidising
ferment (oxidase). The light dies out if oxygen is withdrawn
from the culture or if the bacteria are dried, and reappears on
admitting oxygen and moistening the culture again. The
author discusses the cases of luminosity that have been
described in various flowering plants: for instance, on sultry
nights light is occasionally emitted by flowers, but this is
either an electrical phenomenon comparable with " St. Elmo's
fire " — a faint glow seen at the tips of masts and trees in
thundery weather, and due to the dissipation of atmospheric
electricity in the form of a brush discharge — or it is attribut-
able to the presence of small phosphorescent insects which had
been overlooked by earlier writers on " luminous flowers."
HETEROSTYLED FLOWERS.— In a considerable
number of plants there occur long-styled and short-styled
flowers, as in the Primrose and other species of Primula, and
in some cases (as in the Purple Loosestrife) there may even
be three forms of flower with three lengths of stamen and
style. There is an interesting relation between the size of the
pollen grains and the length of the stigmatic hairs in these
flowers, the rule being that the longer the stamen the larger
are the pollen-grains, and the longer the style the longer are
the receptive hairs on its surface. Heterostyly raises several
interesting problems in heredity as well as in floral mechanism,
and Stevens (Bot. Gaz., April, 1912) has investigated the
development of the pollen and the other points in the life
history of two heterostyled plants — Buckwheat and Houstonia
coerulea. He found that in eighteen hours after " legitimate "
pollination (pollination of long-styled with short-styled) an
embryo began to develop, while in three days after
" illegitimate " pollination (pollination of short-styled with
short-styled or long-styled with long-styled) the pollen-tubes
had not reached the egg. Under natural conditions, there-
fore, there would be very little chance of illegitimate pollina-
tion resulting in fertilisation. The author gives various details
of the cytology and embryology in the two plants he
investigated. He found that in the development of the pollen-
grains the chromosomes in the reduction division are about
twice as large in the short-styled form, and that in the
long-styled form also the central chromosome is considerably
larger in one daughter-nucleus than its mate in the sister
nucleus. He compares this with the " accessory chromosome "
which is regarded as being the " sex determinant " in the
evelopment of the male germ-cells of certain insects.
GERMINATION OF O RCH I DS— Some interesting
observations have recently been made on the fungi which are
associated with the roots of many orchids, forming a
" mycorhiza " or symbiotic (mutually beneficial partnership)
association between the fungus and the orchid. Burgeff and
Bernard have shewn that the seeds of various tropical orchids
will only germinate if the right micro-organisms are present.
By isolating and cultivating the spores or the " spawn "
(mycelium) of these fungi, pure cultures of the appropriate
mycelium can be made and used for mixing with the sphagnum
and fern compost in which the seeds are grown, the seed-pans
and the rain-water used for watering are sterilised, and suc-
cessful sowings are thus ensured.
XEROPHILOUS ADAPTATIONS IN MOSSES.— Grebe
has published (Hedwigia, Band 52, 1912), a useful summary
of the adaptations of mosses for protection against drought.
He limits the use of the term " xerophyte " to those mosses
which grow in situations where they are exposed to fairly
prolonged periods of drought, are dependent upon atmos-
pheric moisture, and are not protected against drought by
other factors of the environment such as shade and damp
atmosphere. Warnstorf regards dependence on atmospheric
moisture, as opposed to that of the soil, as the chief
criterion of xerophily in mosses, but Grebe points out that
various mosses in shaded woods grow on tree trunks and yet
are not xerophilous, being protected against drought-periods
by their shaded and humid habitat. Many of the mosses of
March, 1913.
KNOWLEDGE.
99
shaded woods, however, are more or less xerophilous in
structure, and grow high up on trees, whose crowns admit a
good deal of light. In general, xerophilous mosses are so
constructed that they rapidly absorb rain-water and dew,
and retain it for long, once it is absorbed.
The majority of xerophilous mosses grow on rocks and
trees. They occur from the coast up to the high Alps, the
Grimmias and Andreaeas being the last representatives of the
cryptogamic vegetation seen in ascending the highest hills.
The effect of a dry continental climate is seen in general
scarcity of mosses rather than an increase in the proportion
of xerophilous species. The author then indicates the chief
adaptations shown by mosses for retaining moisture or
reducing transpiration. The chief xerophilous adaptations of
this kind in the sporogonium are absence or shortness of the
seta, causing the capsule to be sessile, or nearly so, and there-
fore enveloped by the upper leaves of the moss-plant; down-
ward curvature of the seta, causing the young capsule to be
plunged among the leaves — later the seta becomes erect for
spore-dispersal ; the presence of warty outgrowths or papillae
on the seta ; the presence of a large calyptra in some mosses
covering the entire capsule ; the hair-clad type of calyptra seen
in the Polytrichaceae and Orthotrichaceae ; the sheltered
position of the stomata, especially in species of Ortho-
trichum with furrowed capsules and the stomata in the
furrows, or in Polytrichum with stomata in the deep ring-
like groove between capsule and apophysis.
The moss-plant itself, or gametophyte, naturally shows a
far wider range of xerophilous or drought-resisting characters.
These adaptations include, above all, perhaps, the cushion-
like habit, the plants being aggregated to form a spongy mass,
which holds water by capillarity ; hyaline hair-points on the
tips of the leaves; reduction in breadth of the leaf-blade, and
corresponding increase of the cylindrical midrib ; leaves more
or less hollowed out or rolled up, undulate, wrinkled, or
folded — all these arrangements providing cavities for the
retention of water by capillarity ; sheathing leaf-bases, as in
Polytrichum; papillae and mammillae (solid and hollow out-
growths respectively of the leaf-cells) ; presence of water-
storing tissue in the leaf ; thick-walled leaf-cells ; increase in
number of layers of the lamina to two or more ; strengthening
of the leaf-margin ; development of plate-like outgrowths or
lamellae on the upper side of the leaf ; presence of filamentous
outgrowths (paraphylls) and dense covering of rhizoids on the
stem ; hygroscopic movements of the leaves.
ALPINE MOSSES AND LIVERWORTS.— Apart from
the familiar moss-carpet of woods, and the bogs largely made
up of bog-mosses (species of Sphagnum), and the woolly
fringe-moss (Rhacomitrium) on moorlands, various mosses
and liverworts play an important part in the vegetation of
certain areas, chiefly in alpine districts.
Under the title " Anthclia: an alpine-arctic plant
association," Dr. W. G. Smith {Scottish Botanical Review,
April, 1912) gives an interesting account of a plant association
which is characteristic of the higher Alps, and which was
noted on Ben Lawers during the international phyto-
geographical tour of this country last summer. This associa-
tion is of special interest as one in which several liverworts
and mosses play the part of pioneers in colonising a substratum
which owes its origin in the first place to topography, and in
the second to the action of running water. Towards the
summit, where the grassy turf becomes more limited, and the
most conspicuous vegetation consists of the woolly fringe-
moss, sedges, and other mat-forming plants, there occur dark
patches, represented on the summit ridge by larger tracts of
almost black mossy crust. These patches and tracts are
known to Swiss botanists, two of whom were with the party
and pointed them out, as '' Schneetalchen," which may be
translated as " snow-flushes."
The formation of these '"snow-flushes" has been traced
in Switzerland and Tyrol, where the rocks and soil,
uncovered by the melting snow, are often covered with
flowers, while the snow still lies a few yards away. As
melting proceeds the snow-water soaks through the
turf, forming a system of temporary watercourses in troughs
of undulating ground, and along the foot of slopes and
escarpments, while the rain-water in summer tends to follow
the same course. On gentle slopes or flats and in depressions,
the force of the flow is not sufficient to carve out channels, as
happens on steep slopes, but the water wanders slowly through
the turf and deposits accumulated suspended matter as a
sediment. The snow-water carries the dust it gathers on
lying snow, mineral particles, and plant fragments, and
collects other materials in trickling over the surface ; snow-
dust may contain fifty per cent, of organic matter, and as this
with the mineral matter is laid down among remains of last
year's vegetation, a rich soil is built up.
The vegetation of the snow-flush begins with flowerless
plants, and these may remain as the dominant vegetation.
Apparently the pioneer plant is the liverwort Anthelia, not
only on Ben Lawers and other Scottish mountains, but also
in the Alps, Scandinavia and Spitzbergen. This liverwort
lies close to the surface, and in the fresh, moist state forms a
bluish-green carpet, but in summer is often dry and dark
brown or almost black ; it is often coated with the threads of
a fungus, and these occur also in the rooting-hairs of the
liverwort — doubtless forming a mycorhiza or mutually bene-
ficial partnership between the two plants. Alpine species of
the moss-genus Polytrichum also occur in the snow-flushes;
these mosses can withstand periodical submergence, and soon
grow through the shallow deposits of sediment laid down, so
helping to bind these deposits into a humous turf, while their
close, compact growth also enables the tufts to withstand
periods of drought. The snow-flush is an open association
into which species of flowering plants from neighbouring
plant communities migrate — Dr. Smith gives lists showing that
several of these species are identical with those found in snow-
flushes in the Alps.
On collating the accounts given by different observers, so as
to obtain an outline of the evolution of the snow-flush vegeta-
tion', we find that Anthelia, probably preceded by algae and
other lower organisms, forms a humous turf ; Polytrichum
follows later, and more or less takes the place of Anthelia ;
later still, Salix herbacea or Alchemilla assumes chief
place, and so on. The successive stages of vegetation
probably indicate stages in the evolution of the habitat, since
the later vegetation will tend to give it increased stability ; in
time the accumulation of sediment, humus, and vegetation
may be such that the snow-water is diverted to new situations,
where the sequence will begin over again ; and during the
various phases other species secure a footing, and flourish
well or ill according as the habitat suits them. The snow-
flush is, therefore, a series of migratory associations.
Crampton, whose important paper on the vegetation of
Caithness was recently summarised in these columns (" Know-
ledge," May, 1912, p. 187), has defined such formations as
follows (Scottish Botanical Review, 1912) : " Migratory
formations are of comparatively short persistence on the same
habitat, which sooner or later undergoes change or destruction,
with renewal elsewhere. Their associations tend to rapid
degeneration from plant invasion. All stages of progressive
successions are encountered."
AIR-CHAMBERS IN LIVERWORT THALLUS.— The
Marchantiales, doubtless owing to the common occurrence of
the familiar Marchantia and Lunularia on the soil in flower-
pots, garden paths, and so on, and Fegatella beside streams,
are often taken as typical of the Liverworts (Hepaticae), though
in reality they form a relatively small division of that group,
the majority of Hepaticae being differentiated into slender
stem and thin leaves. At any rate, the thalloid Hepaticae
are usually selected by teachers of Botany as being the typical
forms, and Marchantia polymorpha is one of the most
frequently studied of plant types. As so often happens, even
the most familiar types repay renewed investigation by those
willing to take the trouble and to remain unbiassed by the
oft-repeated descriptions copied from text-book into text-book.
The air-chambers which occupy the upper portion of the
tissue in the thallus of the Marchantiales, each chamber, in
typical cases, opening to the atmosphere by a pore in the
centre of its one-layered roof, were described by Leitgeb in
100
KNOWLEDGE.
March, 1913.
1879 and 1881 as arising in the same way as the cavities in
which the sexual organs (antheridia and archegonia) are
sunken, namely, by upgrowth of the surrounding tissue of the
thallus. In the simplest case (seen in most species of Riccia),
the chambers are simply deep vertical canals, believed by
Leitgeb to arise as the result of upgrowth of the superficial
cells of the thallus as filaments, each filament being in contact
with its neighbours at certain points so as to bound these
air-canals. In the majority of Marchantiales, however, the
chambers become widened out as the thallus grows, and are
roofed over, the roofing layer arising, according to Leitgeb,
by lateral outgrowth of the uppermost cells of the vertical
plates that form the side-walls of the chambers; while in
some cases the originally simple chamber is partitioned up by
secondary plate-like ingrowths.
In 1907, Barnes and Land (Bot. Gazette, XLIV.) examined
a number of Marchantiales, and claimed that in all cases the
chambers arise by splitting between internal cells of the thallus,
in exactly the same way as the intercellular air-spaces in
the leaves, and so on, of the higher plants.
Pietsch {Flora, Band 103) has published the results of
his careful investigation of the Riccia thallus, the chief
species dealt with being R. glauca and R. fluitans. He
has followed in detail the segmentation of the initial cells
at the growing-point and the origin of the air-chambers,
which in R. fluitans are wide and covered by a roofing-layer
in which a pore may or may not be present. His descriptions
and figures leave little doubt that Barnes and Land are right
in their interpretation of the mode of origin of the chambers ;
but it may be added that Leitgeb's own figures are, as is usual
in his work, extraordinarily accurate considering that he had
not the advantages of modern microtome technique at com-
mand, and that it was simply in the interpretation of what he
saw that he erred in this instance. Indeed, even after the
publication of the paper by Barnes and Land, it appeared to
the present writer, from examination of slides similar to theirs,
that Leitgeb's interpretation might still be the correct one. in
the case of Riccia glauca at any rate. However, the
elaborate work of Pietsch appears to settle the question
definitely. As this author points out, the view put forward by
Barnes and Land that each chamber in the Marchantiaceae
arises from a single primary cell (" mother-cell ") can hardly
be accepted, for according to their description and diagram the
vertical septa between neighbouring chambers would be two
cells thick, while as a matter of fact these partitions are but
one layer in thickness.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon.), F.I.C.
LUMINESCENCE ANALYSIS .—In Lehmann's
fluorescence microscope, which is used with ultra-violet light,
there is a special screen to protect the eye from injury. A
description of this instrument and of the uses to which it may
be put in analysis is given by Dr. O. Wolff in the Chem. Zeit.
(1912, XXXVI, 1039). For example, it has been found that
the particles in crude potashes that show a red fluorescence
consist of potassium sulphide, while the blue fluorescent
particles are mainly composed of compounds of organic and
mineral matter.
Again, this instrument shows that the orange fluorescence
of mercuric chloride is caused by the presence of particles of
mercurous chloride, the fluorescence of which disappears on
heating. If mercuric chloride is chemically pure it does not
fluoresce, but traces of calomel may be detected by the
luminescence test in many of the preparations on the market,
although they would escape detection by chemical tests. When
pure mercuric chloride is re-sublimed in a tube, the orange
fluorescence will appear, showing that traces of calomel are
produced in the process.
In like manner, pure anthracene shows a blue fluorescence,
but when impure fluoresces green, owing to the presence of a
substance showing a yellow fluorescence.
FORMATION OF PETROLEUM PRODUCTS.— It is
highly probable that a process of filtration through porous
media has played a part in the natural fractionation of petro-
leum, and this separation was attributed by Day to the differ-
ences in the speed of the diffusion of the different constituents
through the capillary passages between the granules of porous
earths. From the recent experiments of Gurwitsch, however,
[Petroleum, 1912, VIII, 65) it appears more likely that the
separation is due to the attraction or absorption of the petro-
leum compounds by the particles of the porous earth. Thus,
when the same oil was filtered through different porous media,
the fractionation followed a very different course ; while, on
the other hand, filtration of a benzine solution of a petroleum
product through a siliceous earth termed floridin gave exactly
the same result as when the solution was shaken with the
earth, 9-9 per cent, of the constituents being retained in each
case.
The results of treating a white vaseline for four hours at a
high temperature with forty per cent, of floridin were very
interesting. The original vaseline contained 9-35 per cent, of
paraffin wax, and had a viscosity of 6-7 degrees in Engler's
apparatus, but after the treatment the paraffin wax had fallen
to 6-80 per cent, while the viscosity had risen to 12-6 degrees.
It thus appears that, contrary to the generally-accepted view,
treatment of petroleum products with adsorbent agents may
cause an increase in their viscosity.
POISONOUS GASES FROM OIL FIELDS— Mr. H.
S. Shrewsbury records a case of a man being killed by
breathing the gas at the bottom of a pit beneath a derrick at
an oil well near Pitch Lake, Trinidad (Analyst, 1912
XXXVII, 486). A sample of the gas issuing from the top of
the well was found to have the following composition : —
Sulphuretted hydrogen, 0-2 ; carbon monoxide, 1 -9 ; unsatur-
ated hydrocarbons, 4-4 ; saturated hydrocarbons, 7-8 ;
carbon dioxide, 20-9 ; hydrogen, 31-4 ; and nitrogen 33-4 per
cent.
Since 0-1 to 0-15 per cent, of sulphuretted hydrogen is
fatal to human life, while 0- 15 percent, of carbon monoxide is
dangerous, and 0-4 per cent, of that gas will destroy life in a
short time, it will be seen that the gas issuing from the oil
well was extremely poisonous, and that even when mixed with
about forty-three per cent, of air, as it was at the bottom of
the pit, it would kill in a short time. The gas issuing in
bubbles from the small channels and pools of water on the
Pitch Lake, and that given off by the pitch itself, had the
same tarry and sulphuretted odour as the poisonous gas from
the oil fields. It is remarkable, however, that small fishes
live in the pools, through which this poisonous gas is con-
stantly bubbling.
It is suggested that this emission of poisonous gas from oil
fields is probably not an uncommon occurrence, and that now
that attention has been called to the danger, suitable precau-
tions may be taken to prevent accidents.
REDUCTION OF METALLIC CHLORIDES BY
SODIUM. — A communication by Mr. M. A. Hunter to the
Eighth International Congress of Applied Chemistry (1912,
Orig. Communications, II, 125) gives an account of the results
obtained by reducing certain chlorides with metallic sodium
in a steel bomb. The chlorides of titanium and beryllium
were rapidly reduced to the metallic form, and beads of the
metals were deposited on the walls of the bomb. In the
case of titanium, in particular, the metal was pure and could
easily be separated. Neodymium chloride also yielded the
metal, but in a condition in which it could not readily be
separated from the other substances.
Silicon chloride was also reduced with difficulty to silicon,
while compounds of carbon, such as carbon tetrachloride and
sulphide, yielded elementary carbon mainly in the amorphous
state, though also containing a little graphite and a
microscopic amount of colourless crystals agreeing in
properties with crystalline carbon. Among the by-products
of the reaction were sodium carbide and carbon hexachloride.
March, 1913.
KNOWLEDGE.
101
USE OF COPPER SULPHATE FOR PURIFYING
WATER. — Several years ago an account was given in these
columns of the good results obtained by using copper sulphate
to remove vegetable growths from large reservoirs in the
United States. Since then the process has been adopted in
many other places, and in the Journal for Gas Lighting,
1912, CXIX, 507, Mr. G. Embrey describes the results of his
experience with this method of purification at the Gloucester
reservoirs, the water of which had become coloured and had
acquired a fishy odour owing to the growth of Chara vulgaris.
Experiments showed that as much as one part of copper
sulphate per million could be used without rendering the water
poisonous to fish or to human beings, but in practice a third
of that quantity proved sufficient to destroy Chara and similar
low forms of plant life.
This proportion of the salt was sprinkled over the surface of
the water in the form of a fine powder, which sank to the
bottom before dissolving. By this means the maximum action
of the copper sulphate was brought to bear at the place where
it was most needed. The water, after standing for a period
of three to seven days, had lost its colour and unpleasant
odour, and showed no copper remaining in solution. By
treating the reservoirs in February, when only the diatoms
were present, the subsequent development of Chara. and
confervoid growths was prevented. The trout in the water
were not affected by the treatment, but the destruction of the
vegetable matter caused starvation of the roach. The copper
added to the water was partially deposited in the form of red
cuprous oxide on the stones, and was converted into black
cupric oxide by exposure to the air.
Higher forms of vegetation are not injured by such propor-
tions of copper ; for it was found that algae could be destroyed
in watercress beds without injury to the plants.
THE MANUFACTURE OF CARBON BLACK.— In the
United States a sharp distinction is made between "lamp
black," the soot deposited when an oil or resin is burned in a
limited supply of air, and "carbon black," which is obtained
by applying a cooling surface to a burning flame. A descrip-
tion of the process used in a factory producing about ten
thousand pounds of carbon black a day is given by Mr. G. L.
Cabot in a paper read at the Eighth International Congress of
Applied Chemistry [Original Communications, 1912, XII, 13).
The bulk of the carbon black in the American trade is
derived from natural gas, which is ignited as it issues from the
ground, and consumed in rotating burners which pass beneath
fixed cooling plates, upon which the soot is deposited. Most
of the attempts to produce the black from petroleum oil are
stated to have been commercially unsuccessful.
Carbon black as scraped from the plates has a specific
gravity of about 1-7 after removal of the "air" with which
it is impregnated. It is much superior in tone to ordinary
lampblack, since it possesses a rich " bloom," which makes
it a highly-prized pigment for the preparation of the best kinds
of printing ink and stove polishes. Lampblack, on the other
hand, is mainly used for colouring leather, unvulcanised
rubber and oil cloth, and in the manufacture of paints. Its
chief source is tar oil, which when burned in furnaces of
special construction provided with cooling chambers, yields
from fifteen to thirty-five per cent, of its weight of lampblack.
GEOLOGY.
By G. VV. Tyrrell, A.R.C.Sc, F.G.S.
GEOLOGY OF DARTMOOR. — An interesting Memoir
with this title has been issued by the Geological Survey, and
describes an area of two hundred and sixteen square miles in
Devonshire, including the greater part of Dartmoor. The
geology is, of course, mainly that of the great granite mass
forming Dartmoor, which is intrusive in rocks up to Carbon-
iferous in age. It probably forms a gigantic laccolite whose
upper surface slopes gently under the adjacent sediments.
Patches of contact-altered Carboniferous rocks have been
found a mile within the granite boundary, and these afford
data from which the general dip of the granite below the
sediments can be estimated. Near Petertavy and Marytavy
the angle is from twenty-three degrees to thirty-two degrees,
and its smallness accounts for the great width of the meta-
morphic aureole in that district.
The Dartmoor granite is a coarsely porphyritic rock with
large phenocrysts of white felspar which are arranged in
fluxion-streams near the boundary with the sediments.
Tourmaline is present in most parts. Topaz and cordierite
also occur, but much less frequently. The Dartmoor granite
is of a more normal type than the other western granites. It
is less acid and has suffered less from pneumatolysis. It may
be described as a biotite granite, or granitite with accessory
tourmaline, whereas the other granites from the West of
England usually contain abundant muscovite in addition. Its
felspars are of more basic composition, and oligoclase is
frequently present.
The great mass of the Dartmoor granite and its slow cooling
has led to extensive contact-metamorphism in the adjacent
sediments. The average width of the contact-aureole is one
mile, and as a large variety of sediments of Carboniferous and
Devonian age are involved, a correspondingly large variety of
types of hornfels, spotted slates, and tourmalinized rocks occur,
and shew many different stages of recrystallization. On the
south and south-east the argillaceous sediments have been
converted to fine cordierite-hornfelses. Andalusite slates and
chiastolite slates also occur. A special belt of dark shales is
always the parent rock of the latter. The impure calcareous
sediments which are found within the aureole are especially
susceptible to contact-alteration, and give rise to a variable
series of calc-silicate hornfels, of which the most interesting
are the scapolite-bearing types.
The spilite lavas and intrusive greenstones which occur in
the Devonian and Carboniferous rocks are intensely contact-
altered where they appear within the limits of the aureole.
The spilite-hornfels are fine-grained banded schists con-
taining abundant hornblende, with biotite, felspar, quartz, and
occasionally much epidote. In both the spilite and greenstone-
hornfels occur certain minerals, notably tourmaline and
axinite, which must be ascribed to pneumatolytic origin.
IRON-ORES AND BAUXITES OF NORTH-EAST
IRELAND. — The iron-ores and bauxites, which form a
prominent stratified zone in the midst of the Tertiary basaltic
series of north-east Ireland have been described by Professor
Cole and his coadjutors on the Geological Survey of Ireland
in a recently issued Memoir. These rocks are coloured
bright red, and are conspicuous at the Giant's Causeway,
where they separate an upper series of massive columnar
lavas from a lower series of thinner flows. They were formed
by the weathering of the lavas during a quiescent period of
the Antrim volcanoes. The materials of the interbasaltic
zone are pisolitic iron-ores, laterites, and bauxite clays. The
typical downward succession in Antrim is (3) pisolitic iron-
ore; (2) "pavement," a material with a false stratification due
to coloured streaks of basaltic decomposition, and varying
from a siliceous iron-ore to a lithomarge ; (1) lithomarge, a
decomposed basalt still retaining the joint structures and
showing the spheroidal weathering of the original rock. The
pale bauxite clays in Antrim have been derived from rhyolites,
although the formation of bauxite from basic igneous rocks
has been proved in other localities. They overlie the pisolitic
iron-ore when they occur. The whole of the deposits may be
compared with the products of the process of laterization now
going on in many tropical regions, and resulting in the very
variable material known as laterite. The first chapter of the
Memoir, by Professor Cole, is a valuable summary of views
of laterite-formation. He comes to the conclusion that the
laterites and lithomarges of north-east Ireland must be
regarded as examples of soils and subsoils formed under more
or less tropical conditions in a region of seasonal rains.
MICROSCOPY.
By F.R.M.S.
A RARE (?) ALGA. — Many species of the Oscillatorias are
among the most common examples of low plant life. Some of
them may be found in nearly every pond and pool of water,
on heaths and open spaces, while on wet muddy paths, at the
base of walls, and round trees they frequently show as a dark
102
KNOWLEDGE.
March, 1913.
bluish-green stain. In these cases they appear under the
microscope as fine threads of some shade of green, indistinctly
divided into numerous short cells, and when sufficiently free
exhibit the gliding and oscillating movements which have
given rise to their name. But the family contains also some
more specialized members which are less often met with. In
October last, I came across a solitary example of one of these,
clinging to a piece of Myriophyllum in a pond on Hampstead
Heath. In it a number of separate threads (trichomes) are
enclosed in a sheath -like case of gelatinous matter; they are
somewhat twisted and form a rope-like object. Individually,
they do not differ in any respect from many species of
Figure 94.
Microcoleus subtorulosiis Breb.
oscillatoria, but movement must be very restricted from their
close apposition and confinement within the investment. It
evidently belongs to the genus Microcoleus Des., 1823
{Cthonoblastus, Kiitzing 1843). West says of Microcoleus
— " The filaments are simple, terrestrial or aquatic in habit,
and are furnished with a conspicuous hyaline sheath. This
sheath is more or less cylindrical, not in any way lamellose,
and its apex is generally diffluent. The trichomes are
numerous, closely aggregated within the central part of the
sheath, and often spirally interwoven." My specimen agrees
very well with his M. subtorulosiis Breb, the thickness of
the trichomes being, as he states, about 5/i, the breadth of the
entire organism, including sheath, from 75 to 80/*. He says
" Plants of this genus are very rare in Britain." Dr. Cooke,
" British Freshwater Algae," and " Introduction to Freshwater
Algae," gives three species not corresponding very satisfactorily
with West's ; this specimen seems to resemble his M. terrestris
most nearly. The chief difference in the descriptions is that
he appears to imply that Microcoleus is frequent instead of
rare ; he says of its habitat, " on moist naked ground " and
" on the naked ground by roadsides," and so on. I have only
met with the plant once before, and on neither occasion in any
quantity, but it may occur more often in other parts of the
country than near London. If any of the readers of
" Knowledge " have been fortunate in coming across it in
greater abundance, a note with some details would be welcome
to me, and the Editor would, no doubt, be good enough to
insert it in " Microscopy." Figure 94 represents almost the
whole of the specimen referred to, the remainder being some-
what broken and disorganised. , „
5 James Burton.
QUEKETT MICROSCOPICAL CLUB, January 28th.—
A. A. C. Eliot Merlin, F.K.M.S., sent for exhibition a photo-
micrograph at X 320 of Coscinodiscus heliozoides showing
" pseudopodia," from a preparation by J. D. Siddall.
'Some notes on the Discoid Diatoms" were contributed by
W. M. Bale, F.R.M.S., of Victoria, Australia. The paper is a
survey and criticism of the principal characters which have been
utilised in the discrimination of species in some of the best
known genera of the discoid diatoms. Coscinodiscus, Actino-
cyclus, Asteromphalus, and Actinoptychus are dealt with.
A paper on " British Freshwater Planarians (Rhabdoco-
elida) " by H. Whitehead, B.Sc, was read. While the British
marine Turbellaria have been monographed by Professor
Gamble, the freshwater forms of this country have received
but little attention. The classic monograph on the group
Rhabdocoelida is by von Graff. These organisms vary in length
from about one to twelve millimetres. They are generally
found in ponds, lakes and ditches. The body is more or
less transparent, is slightly flattened and provided with cilia.
There is a mouth, a pharynx, and a sac-like gut. The position
of the mouth varies and affords a valuable generic character.
The excretory system consists of renal organs which in
some cases are somewhat complicated in character. The
nervous system is simple and comprises a two-lobed
brain and a pair of nerves running along the body close
to the ventral surface. Pigmented eyes are sometimes
present, and a statocyst (organ of equilibration) is occasionally
found. Reproduction is usually sexual. The animals are
hermaphrodite, but the male organs ripen first. Freshwater
Turbellaria undergo no metamorphosis. Reference was
made to the green chlorophyll-containing cells found in some
species. Professor Keeble has proved that in an allied
marine form, Convoluta, there is mutual benefit from the
association of these green cells (zoochlorellae) with the
animal. The Rhabdocoels are very difficult to prepare
in a satisfactory manner as permanent objects. The
most successful method is as follows : — The specimen
is placed in a watchglass with a little water, the bulk of
which is withdrawn by a pipette. A drop of Lang's fluid
is then delivered from a pipette on the side of the watch-
glass and allowed to run over the animal. After remaining
in the fluid for ten to fifteen minutes, the specimens are
removed to forty-five per cent, spirit, and are afterwards
passed through alcohol of increasing strengths, stained with
borax-carmine, and mounted in Canada balsam in the usual way.
In a note on Pleurosigma angulatum, E. M. Nelson,
F.R.M.S., stated that in spite of previously expressed opinions,
the apertures in the lower membrane of this and allied forms
can be unmistakeably seen below the intercostals of the upper.
Objective used was a Leitz one-twelfth apo. of 1-4 N. A.
C. F. Rousselet, F.R.M.S., read a note on "Some Rotifers
from Devil's Lake, North Dakota, U.S.A."
A DARK GROUND ILLUMINATOR.— Mr. E. M.
Nelson, F.R.M.S., has recomputed a dark ground illuminator
(see Figure 95) which is particularly useful for the examina-
tion of living bacteria. It is claimed that it produces a
brilliantly illuminated object on a velvet
black background. It can be used with
both dry and immersion objectives, but
the numerical aperture of the latter has
to be reduced by a small stop placed just
above the back lens. A funnel stop is
recommended, which can be fitted to any
immersion objective at a trifling cost, and
can be taken out quite easily when not
required. The great point of the
illuminator is that whereas those at
present in use require a powerful arc-
lamp, Mr. Nelson's can be used with an
ordinary oil lamp and a bull's eye con-
denser, provided that the work is done in a darkened room.
Mr. C. Baker, who is producing the illuminator, recommends a
Nernst lamp with a Nelson Aplanatic bull's eye condenser
attached, but incandescent and petrol gas lamps can also
be used.
ON THE RELATION OF APERTURE TO POWER.—
A theory founded upon mathematical fact there is no gain-
saying, yet, while admitting the theory, one need not always
accept the proposed application of the principle. All praise
is due to Mr. E. Ardron Hutton for the care with which he has
prepared his article, under the above title ; for his clearness
in marshalling his figures, yet when it comes to marching
under his banner I find his colours are not mine.
With his strictures upon opticians, each, according to him,
striving, in large apertures of the micro-objective, to offer
better bargains than his fellows, I am not concerned. True,
my own reading of their catalogues does not confirm these,
but the makers are quite capable of defending themselves,
and need no help from my pen. Then, however, he goes on
to say: "In the above case A (from offering the largest
Figure 95.
March, 1913.
KNOWLEDGE.
103
aperture) would often get the order, the tyro arguing that
increased N.A. meant more resolution and, therefore, better
results. It is altogether forgotten that behind everything is
the human eye, and that this admits of improvement within
but narrow limits."
With the inference he draws from this I am entirely at
issue. The tyro does get more
resolution and better results out
of the larger aperture, within,
of course, certain well-defined
limits, though I doubt whether
A is foolish enough to give it for
nothing. I confess, indeed, to
finding it a little difficult to follow
Mr. Hutton in his arguments to
prove the contrary. Certainly __^^^^fl
there are limits to the ability of
the eye to separate lines beyond
a certain fineness apart. 1 can-
not, however, see the connection
of this with the microscope,
when the very object of the
instrument is to carry on definite
vision still further and further
than the unaided eye can
command.
Up to a certain point I agree.
I admit, taking his words : " An
objective of 0-13 N.A. will
resolve twelve thousand five
hundred lines to the inch. . . .
To accomplish this the objective
must have an initial power of
ten, which, multiplied by ten
(the power of the eyepiece),
and then the one hundred
and twenty-five (the limit of resolution of ordinary eyesight),
gives us the twelve thousand five hundred." Granted, that if
such an objective were constructed, which with the ten-power
eyepiece would resolve just these
number of lines, and no more, i
granted also the limit mentioned
of the observer's vision, he would
not be able to pick up details
in the object of still more fine-
ness. Even if the objective
had double the N.A., could
resolve, in fact, lines of double
the fineness, and these in the ob-
ject; with the ten-power eye-piece
they would still remain invisible.
In this last case, however, what
is to prevent the tyro from
clapping on a twenty-power eye-
piece, when they would at once
be seen ? For myself, I can
separate two hundred and fifty
lines to the inch, yet it often
occurs that details invisible
under an eight-power eyepiece
become clearly defined under
an eighteen or even twenty-
seven. But, then, I do not con-
fine myself to objectives with
narrow apertures. To construct,
indeed, an objective with an
N.A. so limited as to show
things under a ten-power eye-
piece only ; then another of
double the N.A. to be able
to resolve structure of double
the fineness, and no more, under the same conditions ;
would be, to my seeming, to emulate the man who cut
two holes in the door for his cats to go through, the
larger one for the mother cat, the smaller for her kitten,
oblivious of the fact that the larger aperture would suffice for
both. Here, as in other things the greater includes the less.
\
Figure 96. A scale of Butterfly, Vanessa atalanta,
magnified four hundred and seventy diameters.
Taken by an objective of 0-17 N.A.
Figure 97. The same scale taken by Swift & Son's
new two-thirds inch apochromatic objective of 0-30
N.A. Magnified four hundred and seventy diameters,
as before.
microscopical readers of
A micro-objective with reserve of aperture is a whole battery
of lenses in itself, the progress from lower to higher magnifica-
tion being made by changing the eyepieces instead of the
objectives. Five eyepieces ranging from four to twenty-seven
powers will give, with a two-thirds inch objective, on a seven-
inch tube, magnifications of from forty to two hundred and
seventy diameters.
I am assuming, of course,
that the lenses are good ; also
that deep eyepiecing refers
mostly to the low and medium
powers. With an oil immersion
one-twelfth inch I have never
been able to work with advan-
tage with anything higher than
a twelve-power eyepiece, calcu-
lated upon a ten-inch tube.
Here, again, I find myself at
issue with Mr. Hutton. He
says, when speaking of medium-
power lenses, ranging from the
one-inch to the half-inch or
four-tenths of an inch : — " These
admit abundance of light, and
often possess a working distance
equal to three-quarters of their
focal length. They can scarcely
be said to be used for highly
critical work, and will (not ? —
T. F. S.) bear an eyepiece mag-
nification at any rate more than
ten." Then: — "So that nowa-
days every objective of four-
tenths of an inch or lower will
bear an eyepiece magnifying ten
on the one hundred and sixty
millimetres tube. Even then we must be careful as to the
illumination, or we shall only get a foggy glare."
To me this statement is truly astonishing, since, if there is
one thing more than another
which distinguishes these low
and medium powers from the
highest, it is their capacity to
stand deep eyepiecing. Why,
some of my lower powers only
begin to do their work when
under a twenty-seven eyepiece.
This especially applies to a new
two-thirds apocbromat of Swift
and Son, just acquired, of 0-30
N.A.; also to a half-inch of
theirs of 0-50 N.A., and a B.B.
of Zeiss of the same aperture,
all in my possession. I only
speak of my own glasses, but
others, no doubt, of other makers,
will do the same. Knowing what
my own lenses will do under
my own microscope, it would
almost seem that Mr. Hutton's
labours had ceased with compil-
ing his figures, and that he had
taken no further trouble to verify
his conclusions. I should be
sorry to misrepresent him, yet
what is one to think when
theory and fact are so far apart
as here ?
Happily, the micro-camera is
ready to come to our aid to
judge between us, and let the
Knowledge" be the umpires.
True, in theory, photography is supposed to confer extra
resolving power upon the micro-objective, yet in practice I
have never found it so. In this opinion also, I am con-
firmed by Mr. Andrew Pringle, whose authority on the subject
is second to none. I remember many years ago attending a
104
KNOWLEDGE.
March, 1913.
lecture on Photo- micrography given
graphic Society, now the Royal. Aft
asked a question as to the in-
creased resolving power photo-
graphy gave, instancing examples
in the sister science, where
more stars were seen upon the
negative than in the telescope.
A facetious gentleman among
the audience called out : " That
depends upon the plates," mean-
ing, of course, the more holes in
the plates the more stars. Mr.
Pringle's sober answer was that
although he had often seen
details of structure upon the
negative not noticed in the
microscope, when he referred
back to the microscope they
were always there visually. If I
may refer to a matter touching
myself personally, I may say
that though, according to the
Psalmist past the age of man, my
eyesight is as good as ever it
was. What the plate can see, I
can see in the microscope, and
that is the way I test it.
The photo-micrographs here
given, then, may be taken as
true representatives of what
was seen, and not seen, in the
microscope. Figures 96 and 97
are from a butterfly's scale,
Figure 96 being taken with a
lens of 0-17 N.A., the outside
limit Mr. Hutton will allow for a
two-thirds inch. Figure 97 by
my own two-thirds apochromat
of Swift, N. A. 0-30, both mag-
nified four hundred and seventy
diameters, or forty-seven times
the initial power of the objectives
on a seven-inch tube. Now, can
anyone hesitate for a moment
in deciding which picture shows
the most detail ? Photographi-
cally, in the quality of the prints
there is not so much difference.
When we come to examine them,
however, we find that while
Figure 96 shows only the ribbing
running from end to end of
the scale, with just indications
of the coarser cross ribbing at
the tip ; in Figure 97 the cross
striations are crowded from end
to end. Neither can it be said
of the second that the magnifi-
cation (fiqual to a forty-seven
power eyepiece) is too much for
clear definition in the print,
nor again that the image has
broken down, or is foggy. I
would not for a moment, how-
ever, let it be thought that the
objective, by which the first
print was taken, is a bad one.
Indeed, it is very good, but, of
course, cannot show structure
beyond the limits of its aperture.
One might as well expect a pony
to do the same work as a dray
horse.
So much for the lower and
medium powers. I now beg to
by him before the Photo-
er the lecture a gentleman
Figure 98. Part of a scale of the same Butterfly,
magnified one thousand five hundred diameters.
Taken by a half-inch of Swift & Son's, of 0-50 N.A.,
abnormally magnified to compare in size with Figure 99.
Figure 99. The same part of the same scale,
magnified one thousand five hundred diameters to
show bosses on the cross ribs. Taken by a one-
sixth inch of Swift tk Son's, of 0-85 N.A.
deal with another statement concerning some of the higher,
and am sorry to say that to deal will be also to disagree.
Mr. Hutton's ideal aperture for
a four millimetre (one-sixth inch)
is 0-52 N.A., and he says: "It
is, however, useless to give us a
four millimetre (one-sixth) ob-
jective of 0-88 N.A., as its
aperture could not be fully
utilised except by employing such
high power eyepieces, or length-
ening the tube, as would utterly
break down the critical character
of the image. Anything above
0-52 N.A. for such an objective
is of little or no value, and if
working distance is sacrificed to
obtain a higher aperture it is
worse than useless."
Here, again, we can bring
photography in as an impartial,
though striking, witness in the
case. I am lucky also in being
able to reproduce the image of
the same object by the two aper-
tures, or nearly so, he mentions.
Figure 98 was taken by a half-
inch of 0-50 N.A.,and Figure 99
by a sixth-inch of 0-85 N.A.,
both of Swift. The first falls
two points below Mr. Hutton's
ideal, it is true, the other, three
points below the one he repro-
bates, yet I doubt whether it will
affect the definite picture in either
case. Both are taken at twenty-
five times the initial power of a
one-sixth, being, so far as the
half-inch is concerned, equal to
the initial power of seventy-five
times upon a ten-inch tube. My
sole object in this last was that
the two objects of the same
size might be compared, fifteen
hundred being far past the
point, on this glass, of useful
magnification.
Figure 98, however, teaches a
useful lesson in another way.
Practically, there is not much
more seen of the structure than
is shown in Figure 97, simply
long girder ribs with short ones
at right angles between. In
Figure 99 one sees that the cross
ones are beaded, pointing to
further structure in the scale.
This beaded appearance is due
to little bosses, which, rising
from the cross ribs, support a
structureless membrane on the
top. Now, the half-inch being
of 0-50 N.A. gives a slight hint
of this structure, though not
enough to be of much service, as
it appears under a low eyepiece.
So far, however, from a deep
eyepiece helping, it only obliter-
ates entirely what was but
slightly indicated before. The
reason is not far to seek. Assum-
ing that a twenty power eyepiece
is substituted for the one of
ten, each point of structure has
only one quarter of the light.
This being now insufficient
March, 1913.
KNOWLEDGE.
105
to stimulate the optic nerve, the picture is lost altogether.
The failure to define, however, by the glass of 0-50 N.A.,
which is so well shown by the N.A. of 0-85, is not all due to
the want of resolving power in the former. Could the little
bosses be isolated from the cross ribs they would be seen by
the smaller N.A. readily enough. But here, with the larger
aperture of the one-sixth inch comes in another valuable
quality, seemingly not appreciated by Mr. Hutton. It does
not consist of the depth of focus he speaks of. Rather this is
its opposite, allowing two structures, one superimposed upon
the other, and but a little apart, to be separated optically. In
the words of Dr. Abbe, a wide aperture then becomes an
optical microtome. In conclusion, I have not met all his
points, but have already written enough, I think, to give a
good opening for the discussion which I hope
wi" follow- T. F. Smith.
THE ROYAL MICROSCOPICAL
SOCIETY. — At the meeting held on February
19th, the new President, Professor Sims
Woodhead, took the chair for the first time.
Mr. E. J. Spitta gave a very interesting
account of the lenses formerly belonging to
Joseph Lister, which had been presented to
the Society by the Executors of his son, the
late Lord Lister. Many of the lenses were of
great historical interest. Some of them had
been made by Joseph Lister himself, others
appeared to be the first examples produced by
well-known makers. Among the manuscripts
which accompanied the apparatus was a
paper which, so far as Mr. Spitta had been
able to determine, had never been published,
in which Joseph Lister, had in a marvellous
way anticipated the work of Abbe carried out
forty or fifty years later. A remarkable
feature of the lenses made by Lister himself
was the high polish which had been given to
them. This is more to be wondered at seeing
the methods which had to be adopted.
Mr. C. Lees Curties exhibited, on behalf of Mr. H.
Waddington, a striking series of slides illustrating the
development of the Fairy Shrimp (Chirocepliahis dia-
phantis). These included the egg and several examples of
the nauplius in various stages, as well as the young shrimps
and preparations illustrating parts of the full-grown animal.
Dr. Shillington Scales read the notes which were sent with
the slides, from which it appeared that the crustacean while
of only occasional occurrence in England generally, was not
uncommon in parts of Cornwall. To the list of localities
mentioned, Mr. Wilfred Mark Webb added Eton, Mr. D. J.
Scourfield one near Oxshott, while Mr. John Hopkinson
mentioned a record for Hertfordshire.
Mr. D. J. Scourfield described the use of the centrifuge in
pond-life work, pointing out that organisms could be obtained
from water that was apparently free from them by the use of
this apparatus. He said that in the past it had been taken
up rather as a substitute for fine nets, but it should be looked
upon as supplementing them.
Another feature which contributed towards making a most
attractive meeting, was the exhibition of Desmids by members
of the biological section of the Royal Microscopical Society.
TAKING CINEMATOGRAPH PICTURES WITH THE
MICROSCOPE. — We have received a very useful booklet
entitled " Guide to Photo-micrography." It is published by
Mr. E. Leitz, and it was primarily prepared for users of
apparatus supplied by him. In the first place we are told
how to set this up, and to make photographs with the camera
put vertically and horizontally. Special apparatus for photo-
graphing insects, large sections, and solid objects, is illustrated
and described. The photographic side of the work is dealt
with as is also the making of cinematograph pictures.
Altogether the Guide is a very valuable help to those who
wish to take up photo-micrography in connection with their
work or as an attractive hobby.
By
ORNITHOLOGY.
Wilfred Mark Webb, F.L.S.
A SWALLOW RINGED IN STAFFORDSHIRE AND
RECOVERED IN NATAL.— On May 6th, 8911, Mr.
J. R. B. Masefield ringed two swallows (Chelidon rustica)
which were nesting in the porch of his house, Rosehill,
Cheadle, Staffordshire. In the summer of 1912 he again
caught the swallows nesting in the porch but found that only
one of them bore the ring which he had put on in the previous
year. On December 23rd, 1912, a swallow was caught in a
farmhouse eighteen miles from Utrecht in Natal, and this
proved to be the bird which did not return to Cheadle in that
year. Mr. Harry Witherby, who records the occurrence in
British Birds for February, thinks it extra-
ordinary that a swallow breeding in the far
west of Europe should have reached the
south-east of Africa. He finds it is quite
impossible to theorise on a single recovery
of this kind but tells us that we must be
content at present with the bare fact, probably
the most startling one that the ringing of
birds has as yet produced.
Figure 100.
A New Nesting Box for
Nature Study Observations.
NESTING BOX EXHIBITION.— A very
successful exhibition of nesting boxes, held
during the first fortnight of February in the
offices of the Selborne Society, was organ-
ised by the Brent Valley Bird Sanctuary Com-
mittee. The nesting boxes which, when they
were first designed, were described and illus-
trated in "Knowledge" (Volume XXXIV,
page 99), have now reached a stage at which
they are not capable of very much more im-
provement, for they have been modified in the
light of experience and the less successful
forms have been dropped. There was nothing,
therefore, very novel to be seen, though one
box was interesting. Instead of being made
from a small log, it is cut from half a tree
trunk (see Figure 100). This gives it a flat back, and it is
very suitable for hanging on a wall, amongst ivy, for
instance. The top lifts off for observational purposes, and
instead of being fixed by nails driven through metal plates
the box can be hung on a single hook. It is specially intended
for nature study observations, and for use in school gardens
and playgrounds, for it can be put up out of reach and
taken down for examination by the teacher quite easily
when required. As was seen at the Children's Welfare
Exhibition, country children are able to make very excellent
observations on birds which build in the open, and the use of
nesting boxes gives them, as well as their town and suburban
cousins, a chance of studying the nesting habits of
those birds which customarily rear their young in holes.
Another contrivance worthy of mention is an experi-
mental box, made, with the idea of attracting tree-creepers,
from a slice of a curved branch, the object being when
it is attached to a tree to make it appear as if it were
part of the actual trunk.
THE LATE STAY OF SWIFTS.— Mr. H. B. Booth, in
The Irish N atiiralist for February, criticises the expression
used in previous notes on the Swift — " despite the coldness
of August, and the summer, the Swifts did not depart." He
says that the writers should have said because of the cold
August and Summer, for his observations go to show that
with the members of this species the date of their departure
is fixed more by the forwardness of their young brood, and
their ability to undertake the long journey, than by the state
of the weather, or of their food supply at the time of leaving.
As a matter of fact, in the finest summers and consequently
when there is a large supply of winged insect food, the colony
usually breaks up a day or two earlier than in colder and
wetter seasons. It must be obvious that in the former case
the young ones would be better fed, and come to maturity
earlier.
106
KNOWLEDGE.
March, 1913.
PHOTOGRAPHY.
By Edgar Senior.
REVERSED NEGATIVES.— For certain photographic
processes, such as single transfer,
carbon, and photo-mechanical
printing, negatives are required
in which the image is reversed
as regards right and left, in order
that the finished impression may
appear in its correct aspect. The
production of negatives of this
nature may either be accomplished
directly in the camera or indirectly
by stripping the film from its glass
support and turning it, or by
reproduction from ordinary nega-
tives. By the first method the
reversal is generally obtained
through the use of either a metallic
mirror placed at an angle of forty-
five degrees with respect to the
axis of the lens, or by means of
a right-angled prism, from either
of which the image is obtained by
reflection ; in the latter, from the
hypotenuse surface of the prism ;
and in the former, from the
silvered surface of the mirror.
As both of these pieces of appa-
ratus are expensive, and, especially
in the case of the mirror, easily
damaged, a plan very frequently
followed, and which, at the same
time, is capable of giving good
results, is to reverse the position
of the sensitive plate in the dark
slide. When working in this manner it is, of course,
necessary to turn the focusing screen, for the purpose of
making allowance for the difference in the image plane due to
the thickness of the glass.
By the second method the film
itself is stripped from its glass
support. This may be accom-
plished in several ways. In the
case of collodion negatives a
coating of india-rubber dissolved
in benzole is applied to the plate,
and when this is dry (which only
requires a few minutes) a film of
stripping collodion is applied and
allowed to become dry ; the nega-
tive is then placed in a dish of
water containing acetic acid, when,
after several minutes immersion,
the film begins to loosen from
the glass, from which it finally
floats free, and may be turned and
floated on to another piece of
glass which has received a coating
of gelatine. We have also found
the " Lotus stripping films " made
by Messrs. Mawson & Swan very
satisfactory, in which case the
negative is permanently removed
from the glass and used as a film.
When gelatine is the medium in
which the image is formed its
removal from the glass plate is
not so easily accomplished, apart
from the expansion (which is often
unequal) which the gelatine under-
goes, and the consequent distortion
of the image when transferred to another plate. A method
was introduced years ago in which the gelatine plate was
placed in a solution of fluoride of soda and citric acid, and
Figure 101.
Print from the original negative
Figure 102.
Print from a reversed negative
although this method was found useful, the expansion was
considerable and increased with the quantity of citric acid in
the solution. To counteract this the application of a film of
plain collodion was often resorted to. Owing to the evil
results attending the operating
with wet films, methods of stripping
dry were introduced, the film being
first thoroughly hardened by
formalin in order to lessen its
adhesion to the glass plate. For
this purpose the following formulae
due to E. Valenta may be
employed : —
Formalin ... 150 minims.
Water ... 7 ounces.
The negative is allowed to soak
in this solution for ten minutes,
after which it is dried and coated
with enamel collodion. The collo-
dion film should be a thick one,
and, when set, is well washed, and
the negative cut through with a
sharp knife about one-eighth of an
inch from the edge of the plate all
round. After drying the film with
filter paper, the stripping is pro-
ceeded with, and, when accom-
plished, the negative is immersed
in the following bath : —
Alcohol 2 ounces.
Glycerine ... 2 ,,
Water 35
On removal from this solution the
film is laid, collodion side down,
upon a piece of glass which has
been rubbed over with a little of
the glycerine mixture, when a
piece of filter paper is laid on and a roller squeegee gently
applied, after which the plate is stood up and allowed to dry
spontaneously. By the third method the reversed image is
obtained by reproduction from an
ordinary negative. This may be
accomplished in several ways, one
of which is to place a dry gelatine
plate in contact with the negative
in a printing frame, and expose to
a strong source of light (sunlight)
for a sufficient length of time
to obtain a reversed action of
light. A better plan, perhaps, is
to employ the method adopted in
the case of the example shown in
Figure 101, which is due to Mr.
Bolas : — A gelatine dry plate was
soaked for three minutes in a
four per cent, solution of potassium
bichromate, after which it was
rinsed for a few minutes in a bath
consisting of equal volumes of
alcohol and water. The super-
fluous liquid having been removed
by means of filter paper, the
plate was allowed to dry in the
dark. When dry it was exposed
under the negative from which
the print in Figure 101 was made,
for a time that would be required
to obtain a carbon print from
the same. After removal from
the printing frame the plate was
washed until free from the bichro-
mate, and the image then developed
by means of pyro and soda. After
fixing and washing a negative in which the objects depicted
were in the reverse aspect of the original negative resulted,
and from which the print in Figure 102 was made. The
March, 1913.
KNOWLEDGE
107
process itself is simple and with ordinary care is capable of
giving good results, as is shown by the example.
ADON TELEPHOTO LENSES.— We have received from
Messrs. J. H. Dallmeyer, Limited, a notice to the effect that
the manufacture of the "Junior Adon " lens has been discon-
tinued since February 1st, and that they will, therefore, be
unable to execute any further orders for them. The manu-
facture of the well-known adjustable form of Adon telephoto
lens, as well as the large Adons, working at F4- 5, F6 and F10,
for which the demand is very great, owing to the large scale
of pictures and simplicity of manipulation, will be continued
as before. The rapid fixed-focus Adons are meeting with
great success, not only in their use on reflex and other hand-
cameras, but as portrait lenses as well.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A.
FEEDING HABITS OF SERPENTS.— Raymond L.
Ditmars, curator of reptiles in the New York Zoological
Park, gives an interesting account of his observations on
the feeding habits of snakes. They are exceedingly captious
and sensitive. Changes of temperature and light, too much
public inspection, the artificial environment, and so on, affect
their nerves, and they go off their food on slight provocation.
None are vegetarian ; the majority like birds and mammals ;
a few are insectivorous ; the sea-snakes confine themselves to
fishes ; some eat frogs, lizards and other snakes ; some of the
smaller forms condescend to earthworms. There are many
specialisations in connection with feeding, one of the best
known being that of the African egg-eating snake, Dasypeltis
scabra, which swallows eggs three times the diameter of the
thickest part of its body. The jaws are almost toothless, but
a few posterior teeth enable them to grip the food. There is
alternate gripping and engulfing, and the egg slips into the
gullet. There it is cut by the knife-like points of the inferior
processes of the vertebrae which project into the gullet. By
this remarkable adaptation all wastage is avoided. The empty
shell is afterwards passed out again — an absolutely unique
habit. In other snakes that feed on eggs, the shells are
broken by the snake forcing its throat against the ground.
The fragments of the shell pass down to the stomach and are
quite dissolved. In the Indian Elachistodon westermanni
there is a structural adaptation similar to that of Dasypeltis,
but there seems to be no certainty as to its use. Mr.
Ditmars gives circumstantial details as to the diet of a
large number of types, and leaves us with a vivid impression
of the range of diversity in a single sub-class. What a
contrast, for instance, between the diminutive worm-snake
(Glaucoma) of tropical South America, which lies uncon-
cernedly inside the ant-hill devouring the larvae, and the huge
Boa or the Anaconda, lurking in the jungle growth along the
river banks on the watch for a passing peccary, capybara or
agouti. An interesting general point is that with few excep-
tions there is an abrupt and entire cessation of feeding on the
part of gravid females.
A MOTH'S LOVE SIGNAL.— Many experiments have
been made to try to settle the much-discussed question
whether insects hear or not, but they have not yielded
satisfactory results, except in the way of showing that there
are many sounds to which insects which are credited with the
power of hearing pay no attention whatsoever. It is difficult,
however, to believe that all the instrumental music of crickets,
grasshoppers, cicadas, and the like falls on deaf ears ; and
Dr. Karl Peters suggests that the experiments that have yielded
negative results have been too much restricted to sounds that
have no biological significance to the creatures experimented
with. He gives an instance, which he has carefully
studied, which very strongly suggests that there may be
hearing in the strict sense, and that the production of a sound
may be utilised in love-making.
His observations relate to an Alpine moth (Endrosa or
Setina aurita var. ratnosa) which is abundant at Arolla, at a
height of about two thousand five hundred metres. The males
fly about actively ; the females are sluggish and sit mostly
on the tussocks of grass, where they are very inconspicuous.
The males are able to produce a cracking noise, which is
peculiar to them, and the females respond to this, even when
they cannot see the males, by vibrating their body and wings.
The reaction on the female's part begins when the male flies
overhead or settles down close by ; it stops when the sound
stops. It seems difficult to avoid the conclusion that the
female hears the male's love signal. It seems likely that sight
plays a role on his part, and that the tremulous, vibrating
movements of the female attract his attention.
RELATION OF HEART-WEIGHT TO MUSCULAR
EFFORT. — A. Magnan finds that birds with relatively small
wings and very numerous strokes per minute, have a relatively
heavier heart than those with larger wings and more sailing
power. Similarly, in Mammals, the proportion between weight
of heart and muscular development is greater in Carnivores
than in Herbivores. For while Herbivores can keep going a
long time they have not usually that capacity for intense
muscular effort which Carnivores show. It may be noted,
however, that Magnan does not deal with horse or chamois or
antelope, in which intense muscular effort is well known. It
is interesting to notice that the proportion in the deer, the
only large Herbivore measured, is more than double that of
the rabbit. The highest proportion is found in bats which
have such strongly developed pectoral muscles and " violent
effort in their flight."
SLEEPING INSECTS. — Karl Fiebrig has made for many
years a study of insects (in Paraguay), which exhibit definite
sleep-attitudes, quite different from ordinary resting attitudes.
The insects remain motionless and stiff, as if in a trance.
Very characteristic is the clinching of the mandibles which
close upon the supporting object. The whole weight of the
body is often supported by the mandibles, no assistance
being given by limbs or wings. In many cases of "sleep"
the whole pose is unusual, being upside down or in some way
reyersed. The sleeping condition may be artificially induced
by changes in the illumination. When "asleep" the insects
are very callous as regards temperature, wind, touch and the
like. The sleeping pose is often of protective value.
FIDDLER-CRABS. — A. S. Pearse has made an interesting
study of the fiddler-crabs (five species of Uca), which swarm
on the mud-flats at Manila. They live together in enormous
colonies, but there is no social life in the true sense. In fact,
they are extremely individualistic and pugnacious. " Each
individual jealously guards the area about his own burrow,
and immediately attacks any invader of this territory." The
burrow is the centre of activities, and the association for the
place where it is situated is very strong. The great chela of
the male is used as a weapon in fighting, and Mr. Pearse
cannot agree with Colonel Alcock that it is used as a signal to
charm and allure the females. A very interesting description
is given of the way in which the crabs carry mud away from
the burrow and close the opening with a plug when they go
into their retreat.
NEW RHIZOCEPHALAN.— Mr. F. A. Potts describes
an extraordinary parasitic Crustacean, Mycetomorpha van-
couverensis n.g. et sp., a new representative of the Rhizoce-
phala. It occurs on the ventral surface of a shrimp, Crangon
communis, and has a flat mushroom-like body of a pale
yellow colour, with the borders fringed with numerous short
lobes. Colourless, absorptive roots extend into the host
below the nerve cord. The mantle cavity is full of Cypris
larvae. No trace of a male organ or of larval males was to
be seen, and it is suggested that the reproduction may be
parthenogenetic. The same may be true of Sylon and
Sesarmoxenos, two other strange Rhizocephala.
CORRESPONDENCE.
THE FOURTH DIMENSION.
To the Editors of " Knowledge."
Sirs, — I am glad to take this opportunity of replying to
Mr. F. W. Henkel's letter on the above, because he appears
to have a definite argument to offer on the subject. This
argument, if I mistake not, is that experience only gives us
solid bodies, which we, somewhat arbitrarily, divide up into
three dimensions, i.e., that the concept of a three-dimensional
body is not, as the term implies, a synthetic product, but is
given immediately by experience ; whilst the concept of a
one-dimensional object (i.e., a line) is not an element out of
which the former concept is built, but is the product of
analysis. Consequently, says Mr. Henkel, any argument
based on the real existence of one-dimensional objects is
fallacious, because such objects do not in fact, really exist.
But .... in fact, I have a string of buts. First of all, I
would ask Mr. Henkel what he understands by existence.
What criterion of real existence can he offer which denies
reality to that which exists in mind ? But to leave aside the
question of epistemological idealism, surely Mr. Henkel will
not deny the existence of one- and two-dimensional objects as
aspects of three-dimensional objects ; and if this be so,
there is nothing in his argument to prevent a belief
that three-dimensional objects are merely aspects of four-
dimensional objects, and so on ad infinitum. And that
is exactly what I have suggested. Moreover, are all the
objects of experience three-dimensional ? I think not. Who
has ever seen a three-dimensional body ? I have not. What
I only see, and what, I think, Mr. Henkel only sees, are flat,
coloured surfaces (i.e., two-dimensional). We simply infer
them to be three-dimensional, because that is the idea we
gain through our sensations of touch and motion. Indeed, by
combining our sensations of touch and motion with our sense
of duration, we may be said to experience four-dimensional
objects — my experience, for example, tells me that the paper
on which I write has length, breadth and thickness, and also
duration in time, i.e., it has four dimensions.
It is best, I think, "to look at the subject from the point of
view of motion. Experience tells me that I can move (to
some extent at least) in an indefinite number of directions in
space, but these may all be resolved into three (but not less)
directions. The reality of the fourth dimension merely
implies the possibility of movement in a new direction irresolv-
able into these three directions. As I have suggested above,
time may be this direction : its apparent difference from the
spatial directions being due to the fact that we are forced
along time with no option of any other movement so long as
that direction is concerned, and that we seem to have practi-
cally no power to see in the direction of time (unless, perhaps,
memory is a sort of time-sight, and prevision be a fact).
The Polytechnic,
Regent Street, London, W.
H. S. REDGROVE.
SOLAR DISTURBANCES DURING JANUARY, 1913.
By FRANK C. DENNETT.
January was poorly favoured with suitable weather for the
solar observer. Seven days (4, 10, 11, 19,23, 29 and 30) were
missed entirely. On eleven days (5, 6, 8, 9, 12, 13, 20, 21, 22,
24 and 28) the disc appeared free from disturbance, bright or
dark. The longitude of the central meridian at noon, on
January 1st, was 6° 12'.
No. 26. — -A group belonging to December, which continued
visible until January 3rd, and so appeared on the chart last
month.
No. 1. — A group of two spotlets and two pores first seen on
the 14th, in a faculic disturbance approaching the western
limb. Next day only one pore was seen within a ring of
faculae, very near the limb. The group appeared to be
50,000 miles in length.
No. 2. — On the 16th, an elongated faculic cloud well round
the south-eastern limb was seen to contain a spotlet with a
gray companion closely north of it, and a minute pore a little
ahead. It remained visible as a hazy pore on the 17th.
No. 3. — On the 25th, two spotlets were visible, and also on
the 26th, but the distance between them had increased to
37,000 miles. On the 27th two pores were seen but not nearly
so far apart, and there were traces of a minute point nearly in
the place of the rear spotlet, but none were observed after.
The faculic display was also very little. On the 7th some
was visible within the eastern limb, probably the remains of
groups 24 and 24a, which is shown on the chart, longitude
206°-220°, as seen again on the 17th and 18th. On the later
date less conspicuous faculae were recorded, but not measured,
within the north-east and south-west limbs. On the 26th
there was a bright knot at longitude 334°, 18° North latitude.
On the 31st some faculic spots appeared in 30° North latitude
between longitudes 41° and 51°, a little within the north-
western limb, and doubtless were the remains of the disturb-
ance which produced No. 26.
The helpers whose observations have contributed to the
preparation of our chart are Messrs. J. McHarg, A. A. Buss,
E. E. Peacock, W. H. Izzard, and the writer.
Erratum. — On p. 69, line 9 below the first chart, in the
second column, for 228, read 288.
DAY OF JANUARY.
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108
AUXETIC ACTION ON SPORES OF A NEW SPECIES
OF POLYTOMA.
By AUBREY H. DREW.
Author of " The Life History of a New Monad."
Polytoma uvella was originally described by Ehrenberg,
and subsequently studied by Dallinger and Drysdale.
Saville Kent also did valuable work on this organism,
and described a variety differing from the type by the
possession of a red spot on the body, and conse-
quently called Polytoma ocella. Dr. Dallinger
referred to the organism as the Acorn Monad, and
he and Drysdale were able to complete its life-cvcle,
while Saville Kent also added to our knowledge in
this direction by showing that the knob-like appen-
dages at the roots of the flagella, as described by
Dallinger and Drysdale, were really in the nature of
loops. Since the work of these observers little more
has been done with regard to these organisms, nor
has any new variety been described. In Ma}', 1910,
I had the good fortune to examine some Monads
strongly resembling Polytoma uvella, and, indeed, at
that time I classified them as such ; but in February,
1911, 1 again came across the organism in a vegetable
infusion, and noting after careful examination some
peculiarities about it, I determined to study it further.
I discovered with comparative ease that the organism
was certainly a variety of Polytoma, as asexual
reproduction vvas a division into four ; and on care-
fully working out its life-cycle, I observed several
very striking differences from Polytoma uvella, thus
proving beyond a doubt that the organism was quite
a new one. On account of its very striking granular
appearance, I suggest that it should be named
Polytoma granulosa. (See Figure 103.) This organism
varies somewhat in size, but the average is between
one fifteen-hundredth to one twelve-hundredth of an
inch in length, the body is ovate, and is invested
with a distinct cuticle, enclosing uniformly granular
contents. A contractile vacuole is present, which is
situated at the anterior end. The flagella are two
in number, arising from the internal protoplasm, and
piercing the envelope. They are equal in length,
and exceed the body length of the monad. Occasion-
ally they are crossed over each other, giving the roots
a V-shaped aspect. Motion is rapid, but rather
irregular, the flagella being used as the arms are in
swimming, though the former are frequently not vibra-
ted synchronously; hence irregularity in motion arises.
The organism possesses a circular nucleus. This is
situated about the centre of the body, but in ordinary
individuals is invisible, owing to the granular contents.
The nutrition is apparently mainly saprophytic,
but is also holozoic at certain periods in the develop-
ment of the organism. Reproduction is interesting,
and takes place in the following manner. On study-
ing a normal form it will be found in the course of
time that a slight constriction is appearing in the
granular sarcode, dividing the contents into two
equal parts. This constriction deepens, and the
contents retract somewhat at the equator of the
organism. Soon two spherical masses of protoplasm
are formed by this constriction. (See Figure 104;)
During this process the monad is usually actively
swimming, but now it generally comes to a standstill,
and fixes itself anterior end downwards on the slide,
and rapidly vibrates its flagella. Meanwhile each
divided half undergoes a similar process of division,
the fission this time being more or less transverse.
Soon four granular masses are formed within the
envelope, being arranged in a cruciform manner.
Motion now usually ceases, the flagella being cast off,
and the envelope with its contents alone remaining.
A delicate membranous cuticle now forms around
each of the products of fission, and minute flagella
are developed, which commence to vibrate. Finally
the separate organisms force their way out, leaving
the envelope behind them, the entire process
usually taking three or four hours. The method
of anisogamic reproduction is far more difficult to
ascertain, and requires careful and continuous obser-
vation over a length of time. If this condition is
complied with, it will be seen that sooner or later a
somewhat larger form in which the granular contents
have retracted from the posterior end, and with the
nucleus strongly developed, comes into contact with
a normal form. The two adhere by the posterior
ends, swimming being continued. (See Figure 106.)
In the course of an hour or two motion usually
ceases, both organisms adhering to the slide
while the flagella continue in vibration. In
about ten hours the two organisms gradually
melt together, forming an oval sac which slowly
becomes spherical. The sac is very granular and
shows the two vestiges of the envelopes, which
do not participate in the fusion. These vestiges are
as a rule washed away from the sac by currents in
the water, but occasionally persist adhering to it.
The sac remains in this condition for many days,
but it will be found that the contents are gradually
merging into one another, forming an irregular mass
of sarcode within. A constriction now appears in
this sarcode, and division slowly takes place, two
equal and slightly granular bodies of an oval
shape being formed. An envelope appears around
these organisms, and finally they acquire flagella,
and, after a varying period, they escape, leaving
the remnants of the sac. The completion of this
process takes from five to eight days.
109
110
KNOWLEDGE.
March, 1913.
When I had worked out the life-history of the and immediately adhere, the contents coalescing
organism thus far, I naturally imagined that I had very rapidly, and give rise to a swelling between
Figure 103.
Polytoma granulosa sp. nov.
Normal free swimming form.
Figure 104.
Stages in division.
Figure 105.
Last stage in division and
form prior to conjugation.
Figure 106.
Conjugation.
settled the whole life-cycle, and it was only by the remains of the two envelopes. Finally, a round sac
chance that I found that there was more to learn, is formed, with rather thick walls, and finely granu-
These researches had been carried to this point in lar contents, with what is apparently a small bubble
Figure 107. Figure 108.
Stages in formation of winter resting spores.
the summer of 1911, but being desirous of ascertain-
ing conclusively whether the products of conjugation
were ever more than two, I again made a series of
Figure 109.
Sac formed from
conjugation.
Figure 110.
Natural division in winter
spore.
in the centre (see Figures 111 and 113). Practically
every monad in the late autumn forms these sacs,
reproduction by fission not taking place. In the
Figure 111.
Winter
resting spores.
Figure 112.
Induced division in spores
by Suprarenal Extract and
Atropine.
Figure 113.
Controls and spores showing
division. (Suprarenal gland
and Cadaverine).
Figure 114.
Free forms from induced
divisions.
All the figures are magnified 1000 diameters, except 111 which is enlarged 500 diameters.
observations in October, 1911. I then was fortunate
enough to discover that there was a third method by
which a winter resting spore was formed. Two
organisms, both having their posterior ends com-
paratively free from granules, come into contact,
course of some weeks the bubble-like body is absorbed,
leaving the finely granular contents surrounded by
the thick-walled sac. To study these spores further,
they must be kept continually moist on a live
slide of some sort through the winter, when it
March, 1913.
KNOWLEDGE.
Ill
will be found that towards spring the contents are
gradually retracting from the sac wall, and, if at
this stage the organism is very carefully watched day
by day, it will be found that a division of the sarcode
is taking place, in similar fashion to the ordinary one
ahead}' described. Soon, the two organisms separate,
acquire envelopes and flagella, and then the sac wall
appears to give way, and finally they are liberated.
If one of the free organisms is followed, it will be
found to gradually increase in size till reproduction
by fission takes place. The discovery of these
winter resting-spores is important, as it explains how
these organisms can survive the winter. I had
previously noticed that normal forms were never to
be observed during the winter months, and was now
possessed of the explanation. During the autumn
of the present year I was engaged in the further
study of these spores, when it occurred to me that
they formed a very suitable subject for testing the
supposed action of Auxetics. Auxetics are substances
discovered by Dr. H. C. Ross in 1909, while engaged
in cancer research. Dr. Ross, and his colleagues at
the Lister Institute, have shown that certain chemical
bodies are developed during cell-death, and that
these bodies act as excitors of cell-reproduction.
Dr. Ross was further able to observe for the first
time the division of human leucocytes by the action
of these substances. Auxetics can be divided into
two classes, natural and artificial. The natural
auxetics are obtained from dead animal matter,
especially material rich in lymphocytes. The
artificial auxetics are bodies which contain the
Amidine group, such as Theobromine, Caffeine and
Acetamidine. Dr. Ross showed in addition that
alkaloids were excitors of amoeboid action in
leucocytes, and also that they acted as augmentors
of auxetics. It had been suggested by critics that
the mitotic figures obtained by Ross and his
colleagues were artefacts, and I determined to
experiment on the resting spores already described.
Using a live slide containing spores through
which a slow current of water could be passed. I
accordingly prepared a solution containing four
cubic centimetres of a concentrated extract of
suprarenal gland, -2 cubic centimetres of a one
per cent, solution of atropine sulphate and -5 cubic
centimetres of a five per cent, solution of sodium
bicarbonate. This was made up to ten cubic
centimetres with distilled water, and the spores
were kept continuously moist with this solution.
In the course of forty - eight hours a slight
constriction appeared in the sarcode which
gradually deepened, and finally actually division
took place, the products separating. (See Figure 112.)
Controls containing no auxetics gave negative results.
Working again with a very concentrated supra-
renal extract augmented by the action of a one
per cent, solution of Cadaverine I found that out
of a total of forty-three spores in one field thirty-
seven had undergone division within forty-eight
hours. I was not, however, satisfied with this, as
I was anxious to see whether the fully-developed
organism could not be obtained from the spore.
I accordingly worked with the solution just
described, but kept the slide in the incubator at
25°C, examining the same at intervals of two
hours. Division had commenced in forty-eight
hours, in eighteen out of twenty-five in one field
and the fully-developed organisms were formed
after another thirty-six hours in seven of these
eighteen ; three spores actually discharged their
contents, which swam away apparently normal
in all respects. (See Figure 114.) I have also
been able to obtain evidence of division upon
auxetic jelly, containing stain, the full description
of which is contained in " Induced Cell Repro-
duction and Cancer," by H. C. Ross (London :
John Murray). This action of auxetics on these
spores is extremely interesting, as it raises the
point whether the former may not be necessary
to cause the latter to develop in the spring. Pond
water usually contains decaying vegetable and
animal matter, and hence auxetics are probably
present in solution. Whether it also contains aug-
mentors one cannot yet say, though I am making
experiments in this direction. From my own
observations on these spores I am convinced that
mere change in temperature will not explain the
development in the spring, for spores may be
incubated at summer temperature and still refuse to
develop. Whether, with the advent of spring,
auxetics and augmentors are formed in pond water .
in large quantities, and thus cause the dormant life
to awake, is a point still to be settled, but in the
light of present knowledge it appears extremely
probable that the answer is in the affirmative.
I was afterwards able to improve the technique, and
found that divisions could be more certainly induced
if the water containing the spores was placed in
small glass tubes, and the solution containing the
auxetics then added. These tubes are then corked
and placed in the incubator, and kept at 25°C for
forty-eight hours, when portions of the contents may
be examined from time to time. The possible
production of auxetics in stagnant water is interest-
ing, as cancer is often stated to be more prevalent in
districts where stagnant water and decaying vegeta-
tion are present.
In conclusion, I have to express my indebtedness
to Messrs. Watson & Sons, who kindly placed two
of their new holoscopic objectives at my disposal,
viz., a two millimetre immersion and a four milli-
metre dry, with the help of which several of
the illustrations were made.
THE FACE OF THE SKY FOR APRIL
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 18.
Date.
Sun.
R.A. Dec.
Moon.
R.A. Dec.
Mercury.
R.A. Dec.
Ve
R.A.
HIS.
Dec.
Jupiter.
R.A. Dec.
Saturn.
R.A. Dec.
Nep
R.A.
Ulle.
Dec.
Apr.
Greenwich
Noon.
h. m.
o 41*0
0 59^
1 17*6
1 36*0
1 54 "6
2 »3*3
N. 4?4
6-3
8*2
io'o
^■134
h. m. a
21 io"6 S. 20*5
0 47-8 N. 6'i
4 59'4 N.27-8
9 56 9 N.is'9
14 2i"8 S. 17-4
19 11*6 S. 27'5
h. m. °
0 8*8 N. 3*3
0 o'i N. o'9
23 59'i S. o*6
0 5*7 S. fo
0 18*4 S. 0*5
0 36"o N. 0*9
h. in.
2 31*0
2 30*5
2 26*1
2 l8*2
2 7*8
1 55'7
N.2i"9
22*2
2 1 '9
21 'O
ig"6
N.i7*S
h. m. 0
19 9*6 S.22"4
19 n*6 22*3
19 13*4 22 "3
19 14'$ 22*3
19 15*9 22*2
19 l6*7 S.22"2
h. m. c
3 55"2 N.i8*6
3 57'3 l8'7
3 59'5 i8'8
4 1 '7 i9"o
4 4*1 19*1
4 6*6 N.ig*2
h. m.
7 39"9-
7 39 "9
7 39 '9
7 40' 1
7 40*2
7 4<3'5
0
N.21'0
2I'0
21 'O
»x"o
21*0
N.21'0
6
16
Table 19.
Date.
P'
Sun.
B
L
.Moon.
P
P
B
Jupiter.
L t
1 2
T
1
..
Saturn.
P U
Apr.
1
6
11
16
21
26
Greenwich
Noon.
- 26-5
26*4
20'4
26-1
257
-25'I
0
6-2
5'8
5 '4
5'o
-4-6
260 '6
194-6
128 6
62-6
556-6
290-5
- i6*i
-21-4
- 5-6
+ 18-7
+ 17-7
- 6-7
0
-3*2
8*4
8*6
8-7
8*3
-S-o
9
-i-8
1 "7
17
i'7
1 '7
-1*7
0 0
352*2 172*8
61*7 204*1
131 '3 235 '4
200*9 2668
270*6 298*3
340-2 329*8
li. in.
10 2 e
10 18 m
8 24 111
4 20 e
4 36 >"
10 22 ^
ii. m.
7 13 lit
4 IK
5 29 '"
2 33 e
1 41 t
■' 53 '"
0 0
— 2'S ~25*0
2 9 25*2
-3*o " 25*4
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Jupiter Lt refers to the
equatorial zone, L.2 to the temperate zone, T,, T.2 are the times of passage of the two zero meridians across the centre of the
disc ; to find intermediate passages apply multiples of 9 5O21
respectively.
The letters in, e, stand for morning, evening. The day is taken as beginning at midnight.
The Sun continues his Northward march. Sunrise during
April changes from 5-38 to 4-37; sunset from 6-31 to 7-19.
Its semi-diameter diminishes from 16' 2" to 15' 54". A small
partial eclipse of the Sun on the 6th, is visible in Alaska and
surrounding regions.
Mercury is a morning star, well-placed for Southern
observers. Illumination one-thirtieth on 1st, one-half on 30th.
Semi-diameter diminishes from 5i" to 3i". Greatest Elonga-
tion, 27° West on 25th.
Venus is an evening Star, till, the 24th, when it is in
inferior conjunction with the Sun, 6° North of it. Its semi-
diameter is then 29i". It is of interest to see how near
conjunction it can be followed. Sometimes the unillumined
disc appears darker than the surrounding sky. Venus is
4° N. of Moon on evening of 8th.
The Moon.— New 6d 5h48me; First Quarter 14d5h39mw;
Full 20d 9" 31™e; Last Quarter 28d 6h 9mm. Apogee
2d 8he, semi-diameter 14' 45"; Perigee 18d 5he, semi-diameter
16' 29". Apogee 30d lhe, semi-diameter 14' 47". Maximum
Librations, lld 6° E, 12d 7° S., 24d 6° W., 25d T N. The
letters indicate the region of the Moon's limb brought into
view by libration. E. VV. are with reference to our sky, not as
they would appear to an observer on the Moon.
Table 20. Occultations of stars by the Moon visible at Greenwich.
Date.
Star's Name.
Magnitude.
Disappearance.
Reappearance.
Mean Time.
Angle from
N. to E.
Mean Time.
Angle from
N. to E.
1913-
Apr. 9
„ II
,, 12
» 17
„ 18
„ 21
,, 22
,, 23
,, 27
66 Arietis
BAG 1648
BAG 1746
BD+I2°22II ...
80 Leonis
BAG 4682
BAG 4923 :.
ir Scorpii
Lacaille 8248 ...
6-i
6-4
6-5
6-6
6-4
6-5
5 7
31
7-0
h. m.
7 40 e
6 51 e
0 52 ;/;
0 23 111
1 50 111
3 7 "i
0 39 m
2 26 in
45°
66
98
189
139
57
69
116
h. m.
8 29 e
7 53 <
3 4° '"
3 41 '"
1 28 ///
3 4' '"
2 32 m
293°
296
280
353
345
277
180
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
112
March, 1913.
KNOWLEDGE.
113
Mars is a morning Star, but practically invisible.
Jupiter is still badly placed, having been in conjunction
with the Sun on December 18th. It is a morning star. Polar
semi-diameter, I83".
Table 21.
Day.1
West.
East.
Day.
West.
East.
Apr. 1
4i (
D
2«3*
Apr. 1 6
4
0
132
,, 2
4 (
J>
123
.. 17
4'
0 3
.. 3
412 (
J
3
,. 18
42
O
13
,, 4
24 (
J
13
,, 19
4'
U
32
.. 5
13 i
J
42
,, 20
43
C
12
„ 6
3 <
J
124
,, 21
324'
(.
>• 7
32 <
J
4 i«
,, 22
32
O
14
;, s
3' (
J
4 2«
.. 23
0
1324
.. 9
(
J
1324
., 24
I
<s
34
„ 10
12 (
J
34
•> 25
2
O
134
>, 11
2 (
J
134
„ 26
I
O
234
>• 12
1 (
5
24
M 27
3
0
124
.. 13
3 ;
3
12
., 28
321
0
4
,, 14
342 c
J
i«
■• 29
32
0
14
.. 15
43 <
9
2«
,, 3°
4
0
32 <•
Configurations of Jupiter's satellites at 3h m for an inverting
telescope.
Satellite phenomena visible at Greenwich, ld 3h 9m II. Oc.
R. ; 4h 40ra 159 III. Ec. R. ; 4d 5h 16m 11s IV. Ec. D. ;
6d 3h 33m I. Sh. I.; 4h 51m I. Tr. I.; 7d 4h 25m I. Oc. R.;
12d 3h 54m III. Tr. E. ; 13d 4h 3m IV. Tr. E. ; 14d 2h 45m 15s
I. Ec. D. ; 15d 2h 11™ I. Sh. E. ; 2h 56m 58s II. Ec. D. ; 3h 29m
I. Tr. E. ; 17d 3h 13m II. Tr. E. : 19d 2h 32™ III. Sh. E.
4h 34m III.Tr. I.;21d4h38m 57s I. Ec. D. ; 22d lh 47m I. Sh. I,
3h 3m I. Tr. I.; 4h 5ra I. Sh. E. ; 23d 2h 39m I. Oc. R.
24d 2h 56m II. Tr. I.; 3h 10m II.Sh.E. ; 26d 3h 25m III. Sh. I.
29d 3h 41m I. Sh. I. ; 30d lh lm I. Ec. D. ; lh 45m III. Oc. R.
4h 30m I. Oc. R.
All the above are in the morning hours.
Saturn is an evening Star, 6° South-east of the Pleiades.
Polar semi-diameter 8". The major axis of the ring is 39", the
minor axis 17". The ring is now approaching its maximum
opening and projects beyond the poles of the planet.
The planet is too near the Sun for convenient observation
of the satellites.
Uranus is a morning star, but badly placed, having been
in conjunction with the Sun on January 24th.
Neptune was in opposition on January 14th and is
stationary on April 4th. Its motion may be traced on the
map of small stars which was given in " Knowledge " for
December, 1911, page 476.
Meteor Showers (from Mr. Denning's List) : —
Radiant.
Date.
Remarks.
R.A.
1
Dec.
Mar. to May
2630
+
62*
Rather swift.
April 12 to 24
210
-
10
Slow, fireballs.
„ 16 to 25
30'
+
23
Swift, streaks.
,, 18 to 23
189
—
31
Slow, long.
„ 20, 21
261
+
36
Swift, bluish white.
,, 20 to 22
271
+
33
Swift, conspicuous shower.
,, 20 to 25
218
—
3i
Slow, long paths.
„ 30
291
+
59
Rather slow.
April to May
IQ3
+
S»
Slow, yellow.
April to May
296
+
0
Swift, streaks.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which
two hours will overlap with the following one. Thus the
present list includes R.A. 10h to 14h, next month 12h to 16h, and
so on. In the case of Algol variables, the time of one
minimum is given where possible, and the period. Algol,
owing to its brightness, will be given for wider limits.
Table 22.
Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Minimum.
Algol
ST Urs. Maj
h. m.
3 2
11 23
+ 400 ■ 6
+ 45 1
2-3 to 3-4
6 -7 to 7-2
d. h. m.
2 20 49
8 19 0
d. h. m.
Apr. 4 0 57 m
Non-Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Maximum.
h. m.
d.
S Leonis
11 7
+ 6°o
9-o to 13
1894
May 4.
R Comae
12 0
+ 19 '3
73 to 14
3°i*
June 8.
SU Virginis ...
12 1
+ 12 -9
8-8 to 13
205
May 10.
T Virginis
12 10
- 5 '5
82 to 13
339i
May 15.
T Can. Ven. ...
12 26
+ 32 '0
S-6to 11 -8
2904
Mar. 26.
R Virginis
12 34
+ 7 '5
6 • 2 to 1 1 • 1
:4Si
May 4.
RU Virginis ...
12 43
+ 4'7
7 -6 to 1.1 -8
440
May 26.
U Virginis
12 47
+ 6 -o
77 to 13
206 '9
May 29.
RR Urs. Maj.
13 23
+ 62 -8
8-6 to 13
229J
Apr. 3.
R Hydiae
13 25
-22 -8
35 to io-i
425
Apr. 17.
T Urs. Min
'3 33
+ 73 '9
88 to 13
321
Mar. 26,
V Urs. Min
'3 37
+ 74 -8
7-5 to 8-7
7i
Mar. 28.
CORRESPONDENCE.
A PHYSICAL PHENOMENON.
To the Editors of " Knowledge."
Sirs, — Two days after reading Mr. J. C. Clancey's letter, I
came across the following passage in " Memoirs of Benvenuto
Cellini, written by himself," about 1558. Translated by
Thomas Roscoe. Page 295 : —
" Another circumstance I must not omit, which is one of
the most extraordinary things that ever happened to any man,
and I mention it in justice to God and the wondrous ways of
His providence towards me. From the very moment that I
beheld the phenomenon, there appeared (strange to relate !) a
resplendent light over my head, which has displayed itself
conspicuously to all that I have thought proper to show it to,
but those were very few. This shining light is to be seen in
the morning over my shadow till two o'clock in the afternoon,
and it appears to the greatest advantage when the grass is
moist with dew ; it is, likewise, visible in the evening at sunset.
This phenomenon I took notice of when I was at Paris,
because the air is exceedingly clear in that climate, so that
I could distinguish it there much plainer than in Italy, where
mists are much more frequent : but I can still see it even
here, and show it to others, though not to the same advantage
as in France." TRESSILLIAN P. WIGGINS.
" Woodham Mortimer," Lee, Kent.
THE NEW ASTRONOMY.
To the Editors of " Knowledge."
Sirs, — I write this letter to you in the hope of publication,
as it contains the following challenge to the official astronomers
of Great Britain. Can they give any explanation of the
Spectra of Novae, without accepting in toto, Professor
Bickerton's theory of the " Third Body " as an inevitable
consequence of the partial impact of colliding suns, which he
propounded nearly thirty-four years ago ? Nova Geminorum
is still blazing, and a most interesting series of spectrograms
from it are open for their explanation.
During 1911, some time before the star above mentioned
appeared, you published, in September and October, full
details of the theory of the " Third Body," what Professor
Bickerton concluded would be its life history, and the evidence,
a light curve and varying spectra which must accompany such
a phenomenon. Let us consider what he said, and what has
taken place. A Nova shines for many months, and is not the
actual collision of two suns ; which may be of only short
duration, perhaps lasting but an hour. With regard
to this point Professor Barnard may be mentioned, as he
has conclusively proved that neither a collision between
suns nor that of a sun and nebula would have anything similar
to the characteristics of a Nova : which is negative, but has an
exclusion value in demonstrating Bickerton's thesis that the
Nova is the "Third Body" shorn from the grazing suns, and
his claim that every known spectrogram proves it. All
astronomers who have studied stellar impact, from Lord
Kelvin downwards, have entirely overlooked the fact that they
were regarding phenomena similar to the clash of flint and
steel, in which each Nova was a cosmic spark. Professor
Bickerton, alone, deduced this inductively, demonstrated it,
and claims recognition upon the confirmation of all spectro-
grams of novae in existence. Once grasp this simple con-
ception, and the triple mystery of these stupendous explosions
called temporary stars, their thermodynamic power, unique
light curve and complex varying spectra are explained in every
detail. Can official astronomy otherwise account for them ?
The exploding " Third Body " has been entirety ignored, and
one may search in vain through all recognised astronomic
literature without finding any trace of its conception or com-
prehension; though it explains any observation ever made on a
new star. One eminent astronomer though, I believe, admits
there is such a thing, but only to say, " Why make such a
fuss ? " and deems it unworthy of further consideration. I
shall await with interest any alternative explanation of the
spectrograms already referred to. The accounts of the spectra
from N Persei and N Geminorum in their earliest stages,
the only two, I believe, ever obtained during the uprise of
the light curves of novae, are similar to those of an
ordinary star, with black lines, the hydrogen not having had
time to escape. The next day all over the world spectra of
the N Aurigae type were obtained, and the sequence deduced
by Bickerton, showing the hydrogen escaping first in
accordance with his theory of atom sorting and the formation
of ensphering shells, vividly described in the articles in
" Knowledge " referred to, was completely demonstrated,
thus rendering the official enigma of these spectrograms so
transparent that any intelligent child could, explain them.
Professor Barnard tells us he actually has seen this
wonderful crimson hydrogen halo form and disappear ; the
first stage of the phenomenon named by Bickerton " Selective
molecular escape." In a recent address given to the B.A.A.,
Professor Bickerton showed that in increasing perfection of
detail, the South Kensington, Greenwich, Madrid, and Cam-
bridge spectrograms of Nova Geminorum, combined with light
curves, absolutely confirmed the majority of the principles of
the Third Body he dynamically deduced and published a third
of a century ago. and, as he aptly says, they leave no more
doubt of the effect of solar collisions than the wrecked
locomotives and telescoped carriages do of a railway
accident. Yet official astronomy looks on in impotent
silence, not apparently daring to admit the mistake of
ignoring one of the greatest discoveries ever made. The
scientific neglect of Bickerton's "Theory of Partial Impact"
is deplorable and incomprehensible, but, unfortunately, not
without precedent. To mention only the ease of Mendel,
thirty-four years elapsed before the value of his work was
recognised, to the untold loss of humanity. It is just thirty-
four years since Bickerton first published his epoch-making
papers, and I hope, even now' at the eleventh hour, that the
generalization, for which he has sacrificed a third of his life,
may be recognised as the basis of a greater astronomy and its
concomitant, a valid optimistic philosophy.
SYLVESTER N. E. O'HALLORAN.
7, Alma Square, N.W.
THE ALCHEMICAL SOCIETY.
The Second General Meeting of the Alchemical Society was
held at the International Club, Regent Street, S.W., at 8 p.m.,
on Friday, February 14th. The Chair was taken by Mr.
Walter Gorn Old, and a paper was read by Mr. Arthur
Edward Waite (whose many translations of alchemical works
are well known to students) on " The Canon of Criticism in
respect of Alchemical Literature."
The lecturer dealt with the possible existence of a mystic
element, in alchemical literature, from a very early period,
side bv side with the work of attempted metallic transmutation,
and briefly traced its development. The lecturer further
considered what is implied by the fact of this mystical element,
whether it was a question of philosophical and theological
doctrine or one of mystical practice and experience ; and he
pointed out the need of a canon by which to determine which
alchemical texts are physical and which are metaphysical in
their object.
The lecture and an abstract of the discussion has been
published in the February number of the " Journal " of the
Society.
114
STRETCHED FILMS OF LIQUID.
PROFESSOR C. V. BOYS' RAINBOW CUP.
By E. S. GREW, M.A.
One of the chief interests of the liquid film, as displayed, for
example, in a soap bubble, is that its tenuity is such as almost
to bring the observer within reach of molecules. An interest
which is even more popular, and which is not on that account
of less scientific usefulness, is
the extreme beauty of the
reflections of light from the
double surface of a film.
These are apparent in that
commonest of objects, the
soap bubble, but unless one
has the manipulative dexterity
of Mr. C. V. Boys a soap
bubble is difficult to examine
in detail or at leisure. At the
anniversary meeting of the
Royal Society, however, Mr.
Boys exhibited a device which
allows the least accomplished
observer to vivisect a soap
bubble, and to lay bare the
changes which, owing to the
progressive thinning of the
film, it undergoes in its life
history.
The device he has since
called the " Rainbow Cup," a
title which is readily explained
by the most characteristic
appearance of the film when
stretched across the crater of
Mr. Boys' Cup. The cup is a
revolving brass drum, across
the top of which it is easy to
stretch a film or membrane of
soap solution. When the drum
is set spinning the film thins
from its centre to its circum-
ference, partly as the result of
centrifugal action ; partly,
because where the upper and
lower surfaces of the film join
the edge of the drum a sort of
suction pump action is con-
tinually going on. A film, which
is practically a sandwich of
liquid between two stretched
skins, is always joined to a solid
surface like the edge of the
drum in a conical formation,
roughly, thus: —
> <,
and the V's at either end of the film are always sucking away
the liquid in the film.
Now as everyone knows there is a constant play of
iridescent colour on the surface of a soap-bubble. This is
due to the rays of light reflected from it being reflected from the
inner skin, as well as from the outer skin of the film, just as in
a looking glass one may sometimes see two reflections, one
image arising from the glass surface, the other from the
silvered back. Consider now the case of red rays of a fixed
wave length of light falling on the two surfaces of the soap
bubble's film. If the two surfaces are exactly the proper
distance apart, the waves coming back from the inner reflect-
ing surface, may exactly meet and neutralise the waves
Figure 115.
Professor C. V. Boys' Rainbow Cup
reflected from the outer surface — the crests of one series of
waves coming exactly where the troughs of the other series
of waves are situated. If, however, the twin surfaces are
" half a wave length of red light " further apart, or half a
wave length of red light nearer
together, the crests and troughs
of the two sets of waves will
not neutralise, but will rein-
force one another. Thus we
can easily imagine a red reflec-
tion from the film appearing
and disappearing and appear-
ing again, as the film thinned to
appropriate dimensions. But
the different colours of light
have different wave lengths; so
that when the film fails to
reflect one kind of light, it may
yet be reflecting another. The
thickness of the film unsuitable
for showing up the red or the
pink may be suitable for
reflecting the green : then as
the film grows thinner the
pink's turn comes again and
the green disappears, and so
into the other colours, the
blues, violets, straw colours,
into which during the whole of
its life the film is analysing the
white or yellow light falling
on it.
These effects are apprehend-
ed, but are all mixed together
on an ordinary soap bubble
film : but in the film of Mr.
Boys' revolving cup, the
regularly diminishing thick-
ness gives them an orderly
succession. As the film be-
comes thinner the colours
appear in circular rainbow
bands in the following order,
beginning with a film fifty
millimetres of an inch thick : —
pale green, pink, pale green,
pink, bluish green, salmon
colour, bright green, magenta,
yellowish and then brilliant
apple green, blue, purple, red,
yellow, poor white, steel blue,
purple, brown, straw colour,
white, black. Each of these
colours is related to its particular thickness of film which can
be computed. The apple green is twenty millimetres of an
inch thick. When the black is reached, far below the wave
length of any light, the thickness of the film is only stfirciTTrath
of an inch thick.
The black appears in a small spot at the centre of the cup
(and of the spinning rainbow bands) and slowly grows. It
can be made to grow faster by stopping the rotation and
tilting the drum. Then the black film being thinnest and,
therefore, lightest, passes upwards, to the higher edge of the
drum. It continually eats its way into the other colours of
the film and Professor Boys in his paper in the Royal Society's
Proceedings surmises that the areas of black thus formed,
115
110
KNOWLEDGE.
March, 1913.
which assume the form of lines, streams, and meandering
rivers, have steep banks. In certain circumstances a deeper
black is set up within their areas, and this black film may be
as little as the itrnJcTT^th of an inch in thickness. At that
stage one is justified in supposing that hardly more than five
hundred molecules are set end to end through the black film's
thickness.
These divagations of the black aided by stopping and
starting and reversing the rotation of the drum several times,
are productive of a number of very beautiful patterns of
colour: Persian shawl patterns, spirals, and an innumerable
variety of groupings of colour. Perhaps nothing is more
striking, however, than the appearance of the surface of the
film when, a considerable quantity of black having been
allowed to grow, the drum is again rotated. The surface
then appears like the eye of some strange beast, with a huge
black pupil and a rainbow coloured iris.
It will be comprehended, however, that beautiful qs the
colour patterns are they are neither the end nor the aim of
this instrument, which enables many striking phenomena of
the surface tension of films, as well as of their thicknesses, to
be measured and examined. The black film's movements, for
example, provide the means by which the existence of " line
tension " as distinct from, surface tension of a film can be
made manifest. Along the margin of the black area there
exists a tension of the order of nrtrtrtb or Tciciith of a dyne,
the latter amounting roughly to the nineteenth of a grain. A
large number of interesting experiments illustrating the surface
tension can be made ; one of the most striking is that of
laying a loop of hair or of spun glass on the film and of then
treating the film within the area of the loop. The surface
tension immediately pulls the loop into a perfect circle. Small
bubbles of coal gas can be joined to the film, and in this case,
as in that of the spun glass hairs, the portions taken up
can be compared mathematically with the thicknesses of
the film.
The " Rainbow Cup" is made by Messrs. John Griffin, of
Kingsway, to whom we are indebted for the loan of the
instrument from which our photograph of the film, with the
central black spot, was obtained.
REVIEWS.
CHEMISTRY.
Leather Chemists' Pocket Book. — Edited by Professor
H. R. Procter, M.Sc, F.I.C. 223 pages. 4 illustrations.
6^-in. X 4j-in.
(E. & F. N. Spon. Price 5/- net.)
This little book is not intended to take the place of a
laboratory text-book, but to give in a convenient and concise
form outlines of analytical methods and the various data to
which the chemist may have occasion to refer in connection
with leather. Among the subjects dealt with are the analysis
of water, the recognition of vegetable tannins, the estimation
of tannin, and the analysis of oils and fats. As a rule
sufficient directions are given, but in some cases, where more
detail would have been advisable, the reader is referred to the
author's larger laboratory book. This is most noticeable in
the section dealing with oils. For example, on page 147 the
bromine thermal test is dismissed with the remark that it
conveys little information not given more satisfactorily by an
estimation of the iodine value. This is true ; but it omits
mention of the fact that the thermal method gives the result
in five minutes, and is applicable to most oils and fats.
There is a useful section upon microscopical manipula-
tion and another upon the general methods of bacteriological
examination, which might with advantage be amplified.
The book, which is well printed and excellently bound in
leather, should be found of constant use to the class of
chemists and students for which it is intended. „ . .,
C. A. M.
Radium and Radioactivity. — ByA.T. Cameron, M.A.,B.Sc.
185 pages. 23 illustrations. 6j-in.X5-in.
(The Society for Promoting Christian Knowledge. Price 2/6.)
In a book intended for readers who have little or no previous
chemical knowledge we look for simplicity of language and
clear description which assumes nothing to be known before-
hand. These conditions are well fulfilled in this little book,
which gives a most readable outline of the discovery of
radioactivity and the preparation and properties of radium.
Interesting chapters are also devoted to the production of
energy in radioactive changes and its bearing upon the
estimation of the age of the earth ; to the question of the
transmutation of the elements ; and to the uses of radium in
medicine. The book is well illustrated with photographs and
diagrams, and anyone who wishes to have a summary of the
present state of knowledge on this subject cannot do better
than obtain a copy. In the next edition it would be an im-
provement if an index were added. _
C. A. M.
Lead Poisoning and Lead Absorption. — By Thomas M.
Legge, M.D. and Kenneth W. Goadby, M.R.C.S. (Inter-
national Medical Monographs). 308 pages. 4 plates and
numerous diagrams. 8j-in.X5j-in.
(Edward Arnold. Price 12/6 net.)
Though the units of the International Medical Monograph
series are intended chiefly for medical men and for those
whose work lies along the lines indicated by the titles of the
individual volumes, yet the subject of Lead Poisoning is one
of such national and international importance that the text
book on it by Drs. Legge and Goadby ought to find a much
more general audience. There is no Industrial disease which
has attracted so much attention to itself as lead poisoning,
and none in which the interests of manufacture have appeared
to conflict more continuously with those of the workmen. It
is not easy to perceive the reason of this, unless it may be
that in a number of the industries where lead is used women
are employed because the nature of the occupation does not
require unusual physical ability, and that the effects of lead
poisoning on women, who are more susceptible to it than
men, have shocked the philanthropic community. Otherwise
it would be quite easy to show that lead poisoning is the cause
of far fewer deaths and disabilities than arise in many other
occupations ; and, compared with the number of " accidents
of occupations," the proportion of cases of dangerous lead
poisoning is extremely small. The smallness of the proportion
becomes more marked where specific trades, such as that of
painting, are considered ; for, contrary to general belief,
painting is one of the healthiest trades.
It is, however, when all the trades in which white lead, or
carbonate of lead is employed, are considered, that the number
of cases of lead poisoning rises ; and the reason for this is
largely to be assigned to the ignorance of the nature and
causes of lead poisoning. Dr. Goadby, who contributes the
bulk of the chapters relating to the pathology of the disease,
makes it quite clear that while lead poisoning may arise from
any cause by which lead is infiltrated into the system, the
chief danger arises when lead dust is inhaled. It is important,
as Dr. Legge points out, that precautions should be taken by
manufacturers, and should be enjoined, and as far as possible
made compulsory, on workmen, to prevent them swallowing
lead with their meals or in any other way ; but it is far more
important that regulations such as Dr. Legge describes and
prescribes for drawing off the dust by fans should be made
compulsory. Dr. Legge is one of H.M. Medical Inspectors
of factories, and it is to be hoped that the strong line he takes
on the necessity for the highest degree of precaution in the
prevention and withdrawal of lead dust by mechanical
processes will be emphasised by legislation.
March, 1913.
KNOWLEDGE.
117
Dr. Goadby's chapters on the physiological aspect of lead
poisoning are a piece of brilliant pathological investigation.
He shows indisputably the paramount influence of the inhala-
tion of dust, and makes out very clearly the pathological
conditions which give rise to minute hemorrhages throughout
the organism, finally extending to the nervous system, and
giving rise to the characteristic symptoms. He describes,
also, an apparent form of acquired immunity to lead-poisoning,
which appears among some workers ; but it is evident that
while such cases present themselves, there are others in which
there is a specialised sensitiveness to the lead; and it is also
evident that in such cases treatment may become very difficult.
E.S.G.
GEOGRAPHY.
The Lost Towns of the Yorkshire Coast. — By Thomas
Sheppard, F.G.S. 329 pages. Illustrated. 9-in. X5i-in.
(A. Brown & Sons. Price 7/6 net.)
This book, by the able and energetic curator of the Hull
Museum, covers a much wider range than is indicated by its
modest title. In reality it is a very complete geography of the
East Riding of Yorkshire. Since Roman times, according to
one authority, a strip of land averaging three and a half rhiles
in width, or about one hundred and fifteen square miles, has
been swallowed by the sea between Flamborough Head and
Kilnsea. On the other hand the destroyer is sometimes
stayed and land is even wrested back from him. Between
1848 and 1893, seven hundred and seventy-four acres were
lost in Yorkshire, but during the same period, two thousand
' one hundred and seventy-eight acres were reclaimed within
the H umber estuary. Many old towns and villages, however,
have been washed away ; but with the aid of ancient
documents and maps, the author has been able to preserve
their history, and even to indicate their former sites. The
records of the lost towns occupy sixteen chapters. The rest
of the book is taken up by a comprehensive geography of the
district, which includes notes on the geology, natural history,
antiquities, architecture, administration, agriculture, and the
Humber mud. The latter is a particularly interesting chapter.
The book is well illustrated and has been done with a
thoroughness which makes it good reading. r W T
Map Projections. — By Arthur R. Hinks. 126 pages.
19 illustrations. 10 tables. 9-in.X5j-in.
(The Cambridge University Press. Price 5/- net)
This book is written to meet the demand of those who
approach the subject from a purely geographical point of
view, whose mathematical equipment is not elaborate. But
in addition to a knowledge of plane trigonometry and the
rudiments of spherical, some acquaintance with the process
of differentiation and its meaning is required for its perusal.
There are some obscurities here and there in the book.
The writer has confused his symbols for the constant of the
cone (pages 10-11, 76, 78.) The definition of this quantity
given at the head of page 76 requires re-statement. Non-
mathematical readers are not likely to be misled by expecta-
tions of mathematical nicety of phrase, and so not all will
agree that there is danger in regarding the simple conical pro-
jection at first as obtained by the development of a cone.
Some points not quite clear in the book are rendered so by
this method of attack. Again, readers will find it inconvenient
that the mathematical treatment of the various projections in
use comes quite separately from the general discussion in
chapter VIII. There is necessarily a good deal of mathema-
tics in chapters II— VI, but as this is incomplete these
chapters cannot be read intelligently without continual
•references to chapter VIII. Necessarily, too, the tables at
the end are too meagre to be of much service even to those
who are not primarily interested as cartographers. No one
could expect to be able by the aid of a concise text-book to
dispense with regular complete tables, and possibly the space
devoted to them would have been more profitably devoted to
extending chapter VII, which deals with projections in
common use and the recognition of them, and is one of the
most interesting and useful to this class of reader.
Many of these blemishes are incidental to a book which has
not had very many forerunners, and in any case faults are
always easy to find. On the whole, the purpose of the work
has been very fully realised and it will be an acquisition to
intelligent readers of geography. It is the best of its kind we
have seen, and can be most heartily recommended to those
who wish to begin the study of maps. Considering the
limited appeal of books of this type its price is very moderate,
and the get-up is of the satisfactory nature associated with
the Cambridge University Press. a c
MINING.
Safety in Coal Mines. — By Daniel Burns, M.Inst.M.E.
158 pages. 23 figures. 1 plate. 7-in. X5-in.
(Blackie & Son. Price 2/6 net.)
This book is written principally for colliery firemen, whose
work is concerned with the safety of the mine, and on whose
vigilance the lives of their fellow-workmen depend. It is
intended for use as a text-book for the examination firemen
have to undergo in accordance with the New Mines Act, and
to furnish an account of the scientific principles which are
the basis of their practical instruction. The first chapter
contains a simple account of the elements of chemistry,
especially in so far as gases are concerned. The next chapter
describes the constituent elements of the mine gases. In the
third the methods of detecting and testing the compounds and
mixtures which form the mine gases themselves are described.
The fourth and fifth chapters deal with air measurement and
safety lamps respectively. The book is written very simply
and clearly, and should well serve its intended purpose.
G. W. T.
ORNITHOLOGY.
Report on the Immigrations of Summer Residents in the
Spring of 1911. Also Notes on the Migratory Movements
and Records received from Lighthouses and Light-vessels
during the Autumn of 1910. Edited by W. R. Ooilvie-
Grant. By the Committee appointed by the British
Ornithologists' Club. 332 pages. 20 maps. 8f-in. X5S-in.
(Witherby & Co. Price 6/- net.)
The introductory section of this Report (the seventh con-
secutive annual one on the subject) is an admirably brief and
illuminating comment on the contents which follow. These,
as usual, go into great details, but no attempt is yet made to
critically examine or co-ordinate the voluminous material
which has been printed. The editor repeats his expression of
regret at being unable to reduce the size of the Report and
continues to give pages of records similar to those published
for previous years and well known to the student. For
example, particulars are given of the arrival of the Wheatear
in Southern England, during the latter half of March, and
these add nothing to the general knowledge of the occurrence
of this species. It is the converse that would be noteworthy
in this case, namely, a month of March in which the
Wheatear did not turn up in the district named. The Report
schedules the majority of our spring immigrants and gives a
chronological summary of the records under each species, the
movements of some being also illustrated by maps. Under
the other sections of the Report, further observations are also
made on these species (amongst others), and it would be a
distinct convenience, in the absence of any index, to give
references under the scheduled bird to the pages on which
any further notes on the species are to be found. We have
had occasion to look up the Land- Rail (Corn-Crake) and find
that in addition to the main entries on pages 148-150, there
are others on pages 209, 213, 214, 255, 277 and 302, all of
which have to be puzzled out by the reader himself, unaided
by any cross-reference. The great scarcity of this species
now in south-eastern England is well illustrated by there
being no records of it from the counties of Dorset, Sussex,
118
KNOWLEDGE.
March, 1913.
Buckingham, Hertford, Essex, Bedford, Huntingdon, Cam-
bridge, and Norfolk, and only few reports from Kent, Hants,
Surrey, Middlesex, Berks, Suffolk and Lincoln.
Of the autumnal movements (1910) there are particularly
good accounts of the Golden-crested Wren, and of the
unusual irruption of the Mealy Redpoll (Linota linaria),
which, during October, visited in numbers the whole line of the
east coast from the Shetlands to Kent and many inland places.
The first record of the Magpie as a migrant to our shores is
remarked upon, twenty birds having been seen arriving at
Thanet (E. Kent) from the north-east on 28th September, and
fifteen from the north, during an easterly gale, on 14th
October.
The Scottish records, which are so fully published elsewhere,
are only partially utilised by this Report, and it might prevent
misleading conclusions being arrived at, if Scotland, like
Ireland, was excluded from the purview.
H. B. W.
PHYSICS.
Experimental Researches on the Specific Gravity and
the Displacement of some Saline Solutions. — By
J Y. Buchanan, M.A., F.R.S. 227 pages. 12-in.X9i-in.
(Neill & Co. Price 7/6 net.)
The author of this book, who acted as chemist and physicist
on the memorable " Challenger " expedition, has made a close
study of the subject of specific gravity for the last forty years ;
and the present volume is devoted to researches on saline
solutions carried out during recent years by the aid of
hydrometers. As usually constructed, the accuracy of the
common hydrometer depends upon the correct calibration of
the scale, which is marked off by reference to other standards ;
and hence most workers, when conducting precise work on
specific gravities, employ the pyknometer in preference. Mr.
Buchanan shows, however, that by standardising a hydrometer
by reference to its own displacement, it is possible to secure
results of a much greater degree of accuracy than is attainable
by any method involving a series of weighings. Two forms of
hydrometer are described : — the closed type, which may be
made to sink in the liquid under trial by placing weights on
the top, and which is used for the less dense solutions ; and
the open type, which may be weighted internally, and will,
therefore, maintain its stability in the very dense solutions for
which it is used. Full details of the method of standardisa-
tion are given.
The book contains the records of some thousands of observa-
tions, extending over some years, of the specific gravities of
water solutions of a number of salts, ranging in strength from
saturation to iAi of a gram-molecule per litre. Amongst the
salts used are chlorides, bromides, iodides, iodates and nitrates
of sodium, potassium, caesium, rubidium, lithium, barium,
calcium and lead ; and also various mixtures of salts in some
definite proportion of their molecular weights. Many in-
teresting relations between the specific gravities and displace-
ments and the molecular weights are revealed as the result of
accurate observations, and are shown in the form of diagrams
and graphs. Of special interest is the graph on page 154,
which represents the fluctuations in the increment of displace-
ment in solutions of common salt ranging in strength from
J to lis of a gram-molecule per litre, the results indicating a
series of interactions between the water and the salt at these
low concentrations. It would be interesting to compare a
water solution of a non-electrolyte, such as sugar, with those
of salts in this connection.
An observation made incidentally with a supersaturated
solution of calcium chloride is at once remarkable and sug-
gestive. It was noted that this solution, prior to crystallisation,
was in a state of unrest, undergoing a rhythmic series of
isothermal expansions and contractions, which were detected
by the delicate hydrometer used. Further investigation on
these lines with other supersaturated solutions, and with
suffused or overcooled liquids, is highly desirable ; and might
assist in diagnosing the cause of these abnormal states.
The effect of temperature upon the accuracy of the observa-
tions is discussed, and details given of the methods used to
secure a constant temperature during the readings. A favourite
working temperature was 19 ^"C, which could most easily be
attained and kept constant in the room. Many hints for
accurate working may be gathered from the book, which
may be recommended to all interested in the determination
of specific gravities, and also to those engaged in the study
of solutions, who may find in it suggestions for attacking the
various problems from another standpoint.
Chas. R. Darling.
Elementary Physical Optics.— By W. E. Cross, M.A.
311 pages. With many diagrams. 7J-in X5-in.
(The Clarendon Press. Price 5/- net.)
When some years ago some Royal Institution lectures were
delivered on Waves and Ripples in the Air and in the Ether, the
lecturer, while describing and illustrating by many examples
the wave motion of light, was obliged to consign his treat-
ment of optical problems of deflection, refraction and disper-
sion of light on this basis, to an appendix to his lectures,
subsequently published. Mr. W. E. Cross, who is the Head
Master of King's School, Peterborough, has moreboldlygrappled
with the difficulty. It is comparatively simple in illustrating
geometrical optics to convince the pupil of their validity by
using the " ray," or the line, as the unit ; but having been taught
in such a way it will be long afterwards before the boy will
have arrived at sufficient proficiency in mathematics to draw any
general conclusions from the experiments presented to him.
If however the idea of a wave front, or advancing trains of
ripples of light be presented to him, he will understand it, but
he may find a difficulty in reconciling theory with experimental
effects. After all a boy can see a ray, but cannot discern a
light wave.
Mr. Cross compromises. He uses the ray in demonstrating
the action of lenses, mirrors and prisms, but he explains their
action by the change of curvature brought about in the wave
fronts, or by change of velocity, when, as in refraction, the
wave passes from one medium to another. By treating a ray
not as a mathematical conception, but as a narrow cone of
light, isolated from the wave series of which it forms a part,
but possessing none the less all the properties of light waves,
he arrives at a conception which causes no confusion of ideas,
and in which there is no discrepancy between experiment and
theory. The idea is not only sound : it is worked out so well
as to give a solidity and an interest to the pupil's conception
of the nature of light such as the older method cannot impart.
E. S. G.
RADIOACTIVITY.
Studies in Radioactivity. — By W. H. Bragg, M.A., F.R.S.
196 pages. 70 diagrams. 8j-in. X 5^-in.
(Macmillan & Co. Price 5/- net.)
This work by Prof. Bragg forms the latest volume in
Messrs. Macmillan's series of Science Monographs. The
' volumes in this series are intended to represent " the ex-
pression of modern scientific work and thought in definite
directions," and each volume will be by a specialist and
mainly descriptive of his own contributions to the field of
scientific work dealt with. They will thus be more adapted
to the requirements of the advanced student than to those of
the beginner. Prof. Bragg's book admirably fulfils the inten-
tion of the series, and he has very wisely not omitted to
describe briefly the researches of other experimentalists, as
well as his own most valuable ones, which come within the
subject of the work.
Prof. Bragg's researches deal mainly with the passage of
o, /3, 7 and X-rays through gases and solid bodies, the arrest,
scattering and loss of energy of the rays, and their ionising
powers ; and he points out many close similarities (together
with no less marked differences) in the behaviour of the three
types of rays. Prof. Bragg considers that the corpuscular
theory of the 7 and X-rays will prove the more useful, and
brings forth several interesting arguments against the ether-
March, 1913.
KNOWLEDGE.
119
pulse theory. But these arguments all appear to be based
on the assumption that the ionising power of the 7 and X-rays
is entirely due to their conversion into £ rays, the latter
being alone responsible for the ionisation. The experimental
evidence offered for this assumption, however, seems some-
what inadequate.
H. S. Redgrove.
ZOOLOGY.
An Introduction to the Study of the Protozoa. — By E. A.
Minchin, F.R.S. 517 pages. 194 illustrations. 8$-in. X5j-in.
(Edward Arnold. Price 21/- net.)
The recognition during the last decade or so of the extreme
importance of the part played by the lowest of all animals in
the economy of nature — and more especially as regards man
himself — has led to the Protozoa being studied with an amount
of labour and zeal never, perhaps, accorded to any other
group of animals. And among those who have laboured
hardest in this productive field is the author of the volume
before us, who, with the true modesty of a great investigator,
claims for his work only the position of an introduction to the
vast subject he has made his own, and that it is not to be
regarded as a complete treatise. To set forth all that is
already known concerning the Protozoa would, he says,
require a work many times as large. That the present volume
is not intended for amateurs, goes without saying ; its aim
being to supply students who have at least some general
knowledge of biology, with a means of taking up the study of
the Protozoa in real earnest. How important to the biologist
is this study may be gleaned from the single fact that, apart
from all other considerations, it throws " great light on some
of the fundamental mysteries of living matter — as, for example,
sex."
In so wide a field it is essential to concentrate attention on
particular aspects of the group, and Professor Minchin has,
therefore, very wisely laid especial stress on the parasitic
forms, both on account of the biological problems they present
and of their intimate association with the practical needs of
human life. The medical aspect of parasitic protozoans is,
however, very properly left to the doctors, who are furnished
by the author with a solid basis of fact upon which to work.
In his concluding chapter, the author gives some most in-
teresting speculations with regard to the origin of the Protozoa
and the types which should be regarded as most closely
approximating to the ancestral stock. In his opinion the
nearest approximation to that stock would be " a minute
amoebula-form, in structure a true ceil, with nucleus and
cytoplasm distinct, which moved by means of pseudopodia."
To all workers on the subject Professor Minchin's volume is
absolutely indispensable. ., .
The Childhood of Animals. — By P. Chalmers Mitchell,
F.R.S. 269 pages. 36 illustrations. 12 plates. 9i-in. X6i-in.
(Wm. Heinemann. Price 10/- net.)
The subject of which Dr. Mitchell treats in such a fascinating
manner in this volume is to a great extent untrodden ground,
for although we all know that caterpillars change into butter-
flies and moths, and tadpoles into frogs and toads, while the
young of many species of mammals differ to a greater or less
extent from their parents in the matter of colouring, yet the
meaning of these changes and the purposes of youth have
never previously, we believe, been discussed in the thoughtful
and thorough manner characteristic of the present work. The
basis of the work was a course of lectures delivered by the
author to a juvenile audience, at the Royal Institution, during
the Christmas season of 1911-12; and although the work itself
is not a printed version of the discourse, yet it tells the same
story, although in a somewhat different and fuller fashion,
more adapted to the requirements of adult readers. Although
the work makes no pretence to be a complete treatise on
such a wide subject, yet it covers a great deal of the
ground, and records a very considerable proportion of
published observations relating to that period of the life
of animals intervening between birth and maturity. To
review the volume in detail is not possible within our
limits of space ; and we can, therefore, only refer to a few
interesting points. In the chapter on the duration of youth
in mammals, it is pointed out that this period is longer among
the more civilised than among the lower human races, and
that in the former it appears to be still increasing in length.
In rhinoceroses, horses, and tapirs the length of the duration
of youth appears to vary according to the bodily size of
the animals ; and the same also holds good among ruminants,
in which, however, owing to the advanced stage of develop-
ment of the young at birth, the period of youth is unusually
brief. Much interesting information is to be found with
regard to the colour-patterns of young mammals, as contrasted
with those of their parents. In mammals, the author believes
that spots were the primitive type of colouring, and that these
are connected with the tesselated nature of the skin. These
spots mav expand into short stripes, or coalesce into longer
longitudinal or transverse stripes, which undoubtedly help to
render the animals inconspicuous, although this is not the
cause of their development. A uniform coat, which so often
replaces the spots or stripes of the young, but may occur in
the first dress of the latter, is apparently a specialised develop-
ment ; and the same seems to be the case when vivid patches
of colour, which do not correspond with structural differences
in the body, replace the first coat. In the latter case the
object of the pattern, which, unlike the retention in the adult
of a juvenile spotted coat, is generally more pronounced in
males than in females, may serve, by breaking up the outline
of the body, for concealment.
The book should be studied by all naturalists, as well as by
the general reader.
R. L.
Elementary Entomology. — By E. D. Sanderson and
C. F.Jackson. 372 pages. 476 illustrations. 8-in. X5f-in.
(Ginn & Co. Price 8/6.)
The writers of this well-illustrated volume, who are pro-
fessors and lecturers in American science colleges, have
found by experience that no text-books on entomology have
sufficed for their needs ; and they accordingly endeavoured
to produce one which shall meet the requirements of both
elementary students and their teachers. In this, so far as we
can judge, they appear to have attained a high degree of
success; for the book, without being unduly technical, conveys
a good idea of the anatomy, life-history, and classification of
insects, and this, too, in a relatively small space. Of especial
value are the " keys" to the important families of the various
orders of insects, which are evidently drawn up with great
care, and the meaning of which is in many instances made
plain by the aid of explanatory diagrammatic illustrations.
The dominant note of the book is, as might have been
expected, the economical aspect of the subject ; for the old-
fashioned cabinet entomology is, at least to a great extent,
dead and buried, and the modern cult devotes itself to the life-
histories of insects, and their role as carriers of infection to
man and animals and their injuries to live-stock and crops.
The authors, however, very wisely insist that an adequate
knowledge of really useful economic entomology cannot
possibly be acquired merely by a more or less casual study of
the common injurious insects ; and they have accordingly
produced a work which should enable every student to obtain
a thorough mastery of the elements of the subject. R ,
The Evolution of the Vertebrates and Their Kin. — By
W. Patten. 486 pages. 309 illustrations. 9-in.X6J-in.
(J. & A. Churchill. Price 21/- net.)
In this handsome volume Dr. Patten, Professor of Zoology
at Dartmouth College, Hanover, N.H., records his endeavour
to solve one of the greatest and most difficult problems with
which biologists are now confronted. As he remarks,
vertebrates suddenly make their appearance in the geological
record at the close of the Silurian or the commencement of
120
KNOWLEDGE.
March, 1913.
the Devonian, in the form of fully developed fishes. These
are evidently a more highly organised type than any of the
groups of vertebrates by which they are preceded ; and it is
obvious that they must have taken origin either from some of
these preceding forms already known to us, by means of a
strongly-marked transformation, or from other extinct types
with which we are at present unacquainted. On either
supposition, as the author observes, the missing links must
date from the Silurian period : and considering the relatively
large size of the earliest known vertebrates, it is a matter for
surprise that these missing links have not yet been found.
When we reach the Silurian " the main trunk of the animal
kingdom, upon which the whole vertebrate stock rests, is lost,
leaving, without reason or warning, a vast unknown abyss,
beside which the gap between man and his immediate pre-
decessors sinks into microscopic insignificance."
The annelids, the ascidians, Balanoglossus and its rela-
tives have each been claimed in turn as the groups which
came nearest to filling the gap ; but Professor Patten will
have nothing to do with any of them, and he pins his faith to
the arachnids as representing, through the intervention of the
so-called ostracoderms, the stock from which the great verte-
brate phylum has sprung. And, to illustrate his views, he gives
at the end of the volume an elaborate phylogenetic tree, whose
roots are formed by the Protozoa, while mammals, birds, and
reptiles form the topmost branches, with fishes branching off
from the ostracoderms somewhat above the middle of the
stem, and the latter, in turn, standing immediately above the
arachnids. Not that the tree presents anything like a straight
and unbroken trunk ; for the ascidians, Balanoglossus,
echinoderms, annelids, and a host of other forms, radiate out
as complex lateral branches from near the base. Whether or
no his views be generally accepted by morphologists, either
wholly or in part, Professor Patten is to be congratulated on
the completion of a most elaborate and valuable contribution
to our knowledge of vertebrate evolution. „
K. E.
Outlines of Evolutionary Biology. — By Arthur Dendy,
F.R.S. 454 pages. 190 illustrations. 8£-in. X5£-in.
(Constable & Co. Price 12/6 net.)
In claiming that biology should form one of the foundation
stones of a modern system of education, the author points out
that even an elementary study of biological theory should be
preceded by a systematic course of laboratory work in zoology
and botany. To aid students in this is the object of the volume
before us, which commences with an account of a couple of
primitive forms as a basis on which to explain some elementary
ideas with regard to the nature of living things, and the
differences between animals and plants. Then follows an
account of the cell theory ; while in later chapters we are
introduced to the evolution of sex, variation and heredity,
and the evolution of organic nature and adaptation to
surroundings; while in the final chapters we have an excellent
summary of the factors of organic evolution, commencing with
a review of the works of the most eminent exponents of the
theory of evolution, and ending with the evolutionary history
of man himself. The whole subject is treated in a manner
which should render the volume acceptable both to the
beginner and to the student who has had some previous
training ; the freedom from unnecessary technicalities being
a welcome feature. Among many interesting items, we have
been specially enthralled by Professor Dendy's account of a
peculiar organ in the head of a frog, which represents the last
remnant of an unpaired pineal eye. We confess our own
previous ignorance of the existence of such a structure in this
well-known animal, but console ourselves by the thought that
there are probably others who were in the same boat until
they had read the many marvels revealed in Professor Dendy's
excellent volume. r
YEAR BOOK. K' L'
Who's Who in Science — International, 1913. — Edited by
H. H. Stephenson. 572 pages. 9-in. X5f-in.
(J. & A. Churchill. Price 8/- net.)
To this, the second issue of a most useful book, many
additions have been made. The sections already appearing
in the "Who's Who in Science" for 1912 have been enlarged,
while Psychology and Geology have been added to the
sciences represented. An important amplification is the list
of the scientific societies of the world with their addresses
and the many useful details about them. Endeavour has
also been made to extend the list of the world's universities,
and to supply the names of the principals, registrars and
senior professors of all ; but we are sorry to see that quite a
long list of existing universites did not take the trouble to
respond to the editor's request for information. We might
emphasise the international character of the publication and
say in conclusion it bids fair to be indispensable to every
serious worker in science.
NOTICES.
USEFUL KNOWLEDGE SERIES.— We have received
from Messrs. Hodder & Stoughton a list of new forthcoming
publications, including the titles of the books coming under
the above heading, as well as several for amateur gardeners
and the first four volumes of the Open-air Series.
MACMILLAN'S NEW BOOKS.— The classified list of
books issued by Messrs. Macmillan during the past month
contains many dealing with scientific matters and education.
FRANCO -BRITISH TRAVEL CONGRESS. — It is
intended to hold this congress in September, 1913, under the
presidency of Lord Montagu of Beaulieu. From the proposed
Agenda which has reached us, it should prove of considerable
usefulness; and we notice in the first number of France,
the official organ of the Franco- British Travel Union, which
accompanies the Agenda, some interesting notes by Count
Plunkett, F.S.A., on the Museums of France and Algeria.
THE JOURNAL OF THE ALCHEMICAL SOCIETY.—
We welcome the appearance of a new journal, the first
number of which (price 2s.) contains a paper on " The Origin
of Alchemy" by our contributor, Mr. H. Stanley Redgrove,
B.Sc, with a resume of the discussion which followed its
delivery. The journal is published for the Society, by Mr.
H. K. Lewis, of 136, Gower Street, W.C.
A NEW COMPANY.— In future the business of Mr. J. H.
Steward will be carried on by a private limited liability
company under the style of J. H. Steward, Limited, at
406, Strand, London, W.C., from which address all outstand-
ing liabilities will be discharged by the Company.
THE GOLDEN EAGLE.— Messrs. Witherby & Company,
the publishers of " The Home-life of a Golden Eagle " have
by special request prepared enlargements (measuring nine
and a quarter by eleven and a half inches) of six of the
principal photographs which were reproduced to form the
plates in the book.
THE RAMBLERS' HANDBOOK.— The Federation of
Rambling Clubs has issued for the first time a useful hand-
book containing many valuable hints and much information as
to maps, houses of refreshment, ramblers' books, and so on,
alitor the modest price of 2d. The energies of the Union are
primarily directed towards obtaining advantages for and giving
help to the constituted clubs, but the good work which is done
is helpful to all who ramble about the country. The Honorary
Secretaries may be addressed at 25, Victoria Street, Westminster.
THE BRITISH ASSOCIATION.— For the meeting of
the British Association, which will take place in Birmingham
on September 10th to 17th next, the following sectional
presidents have been appointed : — A (Mathematics and
Physics), Dr. H. F. Baker, F.R.S. ; B (Chemistry), Professor
W. P. Wynne, F.R.S.; C (Geology), Professor E.J. Garwood ;
D (Zoology), Dr. H. F. Gadow, F.R.S.; E (Geography),
Professor H. N. Dickson; F (Economics), Rev. P. H.
Wicksteed; G (Engineering), J. A. F. Aspinall, M. Eng. ; H
(Anthropology), Sir Richard Temple, Bart., CLE. ; I (Physi-
ology), Professor F. Gowland Hopkins, F.R.S. ; X (Botany),
Miss Ethel Sargent, F.L.S.; L (Education), Principal E. H.
Griffiths, F.R.S.; M (Agriculture), Professor T. B. Wood.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
APRIL, 1913.
EXPERIMENTS ON LIQUID DROPS, GLOBULES,
AND COLUMNS.
By CHAS. R. DARLING, A.R.C.Sc.I., F.I.C.
II.
LIQUID COLUMNS.
If a large drop of liquid be formed in a shallow
layer of water (after the manner described in the
previous article), so that the drop reaches the bottom
of the vessel before parting, it will generallv spread
so as to take the shape of the
lower portion of the vessel ; and
if the upper part of the drop be
brought to the surface of the
water, and the delivery tube be
detached, a column of the liquid
may form. In practice, however,
it is not easy to obtain a liquid
column in this manner ; but by
carrying out the following instruc-
tions the formation may be
secured with ease and certainty: —
Take a test-tube 2-5-cms. (1-in.)
or more in diameter, and nearly
fill the hemispherical end with
water. Incline the tube, and pour
uceto-acetic ether very gently down the side, until the
level of the liquids rises about one centimetre in the
cylindrical part. On erecting the tube, a column,
similar to that shown in Figure 116, will he formed,
the upper part being attached to the surface of the
water, whilst the lower end rests on the test-tube.
The curved sides of the column will be seen to
possess a most graceful outline, and are bounded by
water. The shape of the column thus formed may
UGL
A column of aceto-
be varied by employing a wider tube, in which case
the column will be relatively narrower at the top ; or
by gradual additions of water, which stretch the
column longitudinally, causing the diameter at the
middle to diminish until breakage
occurs. The change produced by-
adding successive small quantities
of water is shown in Figures
117-120, which represent four
stages in the stretching of a
column of Iso-butyl benzoate.
The varied outlines of the columns
are extremely pleasing, and the
last picture of the series shows
the width at the moment of
breakage, which in this case
occurred during exposure, the
column appearing in faint outline.
After severance, the greater portion
sinks to the bottom of the tube,
the remainder hanging from the surface in the form
of a globule. It may be added that the water should
be allowed to trickle down the side of the tube,
as, if dropped directly on to the column, water-
bubbles are formed which impair the shape.
It might he expected that any liquid slightly
denser than water would, if insoluble, form columns
in the manner described. This is not the case, how-
ever, for reasons which at present cannot be entirely
K li 1 1 f).
acetic ether in water.
121
122
KNOWLEDGE.
April, 1913.
Figure 118.
explained. Orthotoluidine, for example, does not
lend itself to these formations : and in the case of
aniline a vessel of five centimetres in diameter is
required, and even then it is difficult to prevent the
column from sticking to the side, and so spoiling the
shape. Iso-butyl benzoate,
as purchased, varies con-
siderably; the first sample
procured by the writer
behaved ideally, as in
Figure 117, but three
other specimens since
obtained have entirely
failed to produce satis-
factory columns. Hence
^Figure 117 '* *s recommended, when
it is desired to produce a
column with certainty, to
use aceto-acetic ether,
which has given uniformly
successful results.
The Movements of
Liquid Globules on
a Water Surface.
Investigations of move-
ments on the surface of
water have hitherto been
restricted to the rotation
of camphor and a few other solids, and to the forma-
tion of films of oil, which spread across the surface
rapidly in all directions from the spot on which the
oil is placed. Whilst experimenting with aniline
and orthotoluidine with a view to the formation
of drops, the writer observed that the globules which
floated on the surface of the water showed move-
ments of a type not previously recorded, and for
which no satisfactory explanation has yet been
given. So far no photographs have been secured
which give an idea of the nature of the movements
in question, and hence it will be necessary to resort
to drawings in order that an idea may be formed as
to the nature of the phenomena. The accompanying
illustrations are the work of Mr. W. Narbeth, one of
the writer's students, and correctly represent certain
stages ; but to observe the movements to full advan-
tage it is necessary to perform the experiments. In
order to produce surface globules, a dish, ten centi-
metres or more in diameter, is taken — a photographic
dish answers well — and rinsed several times with
tap-water before it is filled. One or two drops of the
liquid under trial are then allowed to trickle down
the side of the vessel on to the water, when globules,
sooner or later, will form. A dropping bottle or fine
pipette will be found convenient for regulating the
quantity of liquid, which, if too large, may obscure
the movements.
When a drop of red-coloured, commercial aniline
is thus floated on clean water, globules are formed
which display movements best expressed bv the word
" twitching." What actually occurs is that the
globule is stretched at first, but afterwards recoils,
forming a globule of less diameter and greater depth.
This alternate expansion and contraction is accom-
panied by the detachment of small globules from the
rim, which becomes indented as shown in the largest
globule depicted in Figure 121, the small globules
being formed from the protuberances. After shrink-
ing, the appearance presented is indicated by the
second largest globule in Figure 121, which is shown
surrounded at a distance by the small, detached
globules. Finally, owing to continued partition at
the rim, the diameter diminishes until, at a certain
point, the movement ceases, leaving a number of
small globules floating tranquilly on the water. If
only a minute quantity of aniline be used, the
globules may disappear entirely by spreading over
the surface or by solution.
The next movement to be described is even more
remarkable, and was first obtained by the author
with orthotoluidine, but was only shown to perfec-
tion by one sample. Other quantities of the liquid
since obtained have failed for some reason to produce
equally good results ; but the same movement is
exhibited by the liquid xylidine 1-3-4. The globules
formed when one or two drops of this liquid are
allowed to run on the surface of water are endowed
with remarkable activity. Simultaneously, all the
globules above a certain size become indented on
one side only, so as to resemble a kidney in shape,
when each is projected
violently across the surface
of the water. Some of the
forms taken by the
globules are shown in
Figure 122, in which it
will be seen that in the
process fragments are
broken off the larger ones ;
and sometimes the in-
dentation spreads to the
opposite side and cuts
the globule into two. A
period of repose then
Figure 119.
follows, in which the
globules all possess a
circular outline ; when
suddenly, moved by a
common impulse, all the
larger globules again
assume the kidney shape
and dart across the sur-
face. This continues
until a number of small
globules are left quietly
floating on the surface ; or
the whole may disappear
by spreading and solution.
Sometimes the movements will continue, with increas-
ing sluggishness, for an hour or more. The direction
of motion across the surface is always away from the
indentation, as if the globules were pushed by the
Figure 120.
^Figures 117-120. A column of iso-butyl benzoate, stretched by adding water until breakage occurs. Four stages.
April, 1913.
KNOWLEDGE.
123
force which forms the cavity. Professor Boys has
facetiously suggested that this should he termed the
" kidney-disease " experiment.
The manner in which a film of liquid on the
surface of water breaks into globules is shown in
Figure 123, and is best observed with dimethyl-
aniline. When a very small drop of this liquid
is allowed to trickle on to water, it spreads out into
a film of irregular shape, from the thin edges of
in the centre and remain on the surface in the form of
rings, interspersed with plates containing several holes.
The surface movements described are only selected
examples of a large number observed by the author ;
and it will be noted that the indentation of the edges
of the globules or films is a common feature. There
is little doubt that these indentations arise from the
interplay of the tensions at work, but it is not
evident why an aniline globule should be uniformly
Figurk 121.
Aniline globules on a. water surface.
Figure 122.
Movements of orthotoluidine globules on
a water surface.
Figure 123.
A film of dimethyl-aniline breaking into
globules.
which a number of small globules immediately form.
Indentations then appear round the edges, which
branch out into coral-like shapes, and simultaneously
holes appear in the film from which similar branch-
ings arise. The various channels unite in numerous
places, thus cutting the film up into numerous small
portions, each of which immediately becomes circular
in outline; and by this beautiful process a film is
resolved into globules in a few seconds. In order to
see this remarkable movement to advantage, an ex-
ceedingly small drop of liquid must be used, and the
water must be perfectly clean tap-water. The same
action can be observed with qitinoline, in which case
the division occupies a much longer time ; and the
globules formed, afterafew minutes, become perforated
indented, whilst only one side of a globule of ortho-
toluidine is attacked. The movements introduce
new features which do not appear to be capable of
explanation by the usual theories of surface tension.
It may be added that the movements may be
shown to great advantage by the aid of a lantern
provided with a horizontal stage, vessels with a
bottom of plate-glass being preferably employed.
Sufficient materials for showing the phenomena a
large number of times can be procured at a small
cost ; and when once seen it will be realised how
completely inadequate any verbal description must
of necessity be to convey to the mind the beauties of
the movements. Hence the writer hopes that all
who read will try the experiments for themselves.
NEGRO MAN IN BRITAIN.
UNDER the auspices of the Celtic Union, Edinburgh, a lecture
was delivered on the 21st of February, by W. J. Edmondston-
Scott, M.A., author of " Elements of Negro Religion," in the
Philosophical Institution, on "The Age of the Stone-circles:
or Negro Man in Britain." Mr. David MacRitchie, F.S.A.,
Scotland, presided.
The lecturer discussed the many aspects of the " pre-Aryan "
problem with particular reference to pre-Celtic Britain, its
ethnology, history and antiquities. He showed that the
deeper scientific researches descended into European
Ethnology, the more and more assertive became the Negro
type of physiognomy — as evidenced by the anatomical
characters of the oldest prehistoric skulls, — a fact which
argued the former existence of a negro race of Aborigines
in Middle and Western Europe, most probably associated
with a milder and more equable climate than ours; that the
character and contents of Cave-deposits and River-drifts
testified to general differences in Negro Culture; and that
the infinite variety of Culture - stages represented from
Mousterian to Neolithic and later times was just such as
prevails universally throughout Modern India. He indicated
how man's antiquity in Europe resolved itself into the
problem of the age of India's native civilisations, whose
pre-historic culture in every stage and form had been diffused
over the European Peninsula at a very remote period ; and
how the Eastern origin of this negro species pointed to its
affinities with the Kolarian Aborigines of Bengal — the only
negro race in the whole Asiatic mainland — from one of whose
ancient tribes, now represented by the Baske, were descended
the Basques of Europe, as could be proved from the remains
ol their archaic speech and the vestiges of Kolarian culture
among them. On linguistic and ethnological grounds the
lecturer concluded thai the so-called "Pre-Aryan Problem"
vanished with the solution to the old-time mystery about the
origin of the Basques, and was one to which the scientific study
of the Kolarian languages offered the only means of solution.
Figure 124. The Site of the Emerald Mines.
PREHISTORIC EMERALD MINES.
By LEOPOLD CLAREMONT,
Author of " Ceylon, the Island of Jewels," " The Gem-Cutter's Craft."
In 1812, a Frenchman named Cailliard rediscovered
a series of anciently-worked emerald mines, the
history of which is lost in antiquity.
They were found in a desolate mountain range
which lies west of, and parallel to the Red Sea
hetween the 24th and 25th lines of latitude.
He was one of
a party of ex-
plorers sent by
Mehemet Ali
Pasha, to en-
deavour to locate
the mines of
Ethiopia, whence
the ancients ob-
tained their emer-
alds, and to which
old inscriptions
refer, but of which
all trace had been
lost. It is a matter
of history that
Cleopatra caused
her portrait to be
engraved on em-
eralds, and there
is also the legend
of Nero viewing
the burning of
Rome through
one of these stones. Moreover, emerald jewels
are to-day found in the ruins of ancient cities,
and enclosed within the bindings of Egyptian
mummies, so there can be no doubt that the gems
;M>
" i'**
4 -^d~
"
' -
<**•.
Figure 125. A good geological section.
were much appreciated at a most remote date.
The result of Cailliard's investigations and also
those of a British expedition of recent years, was the
discover}- of quantities of emeralds of large size but
poor quality, which in every respect resemble the
ancient jewels referred to above.
There is little
doubt but that
the Frenchman
was successful in
his quest, and
that the mines
which he found
are the actual
ones from which
the gems were
taken in ancient
times. For con-
vincing evidence
that this is the
case, is the ap-
pearance of the
mines at the
present time.
These mines,
to which the
name "Cleopatra
Emerald Mines "
has been given,
are situated in a
barren region traversed by several picturesque wind-
ing valleys, the principal of which is known as the
Wady Djemel.
A wady is a valley formed by an ancient water-
124
I ■
FlGUKE 126. A wady of coarse sand.
FIGURE 127. An artificial passa;
i
FIGURE 128. The entrance to one of the emerald mines.
Figure 129. Part of one of the ancient buildings.
125
126
KNOWLEDGE.
April, 1913.
course which has during the lapse of ages
become dry or nearly so.
The hills consist of strata of hornblende,
soapstone, mica schist, talc schist and
augite. It is in the mica schist that the
crystals of emerald occur.
In several localities, viz. : — Sikait,
Nugrus and Zebara, the schist which is
a comparatively soft material, is found to
be honeycombed with long subterranean
tunnels and chambers, some of which are
large enough to contain hundreds of men
at work. Many of the small winding
passages are situated one above the other,
and the division between them is so
slight that unless the explorer exercises
great care, he will, as he crawls along, put
his foot through into the tunnel below.
That these excavations were made
anciently is shown not only by the primi-
tive nature of the work, but by the finding
of such articles as tools, lamps and baskets,
which evidently were left behind by
the early workers when for some unknown reason
they decided to abandon the mines. Some of the
cavities are shored up with wooden supports which,
although apparently of great age, are still intact.
It has been ascertained that some of the objects
found belong to as early a period as 1660 B.C., but
the date at which the excavations were commenced
is quite unknown.
There are also indications that after the workings
were originally deserted, they were at several subse-
quent periods visited and re-worked possibly by
members of a race altogether different from their
predecessors. This assumption is warranted by the
fact that much of the obviously later work is
executed with greater skill than the earlier, and that
Figure 130.
Interior of ancient building showing walled-np recesses.
Figure 131.
A typical view of the mountains where the emeralds are found.
it is followed by some of a primitive nature. It is
probable that the Romans were responsible for the
best of the work done.
When working the mines the workers evidently
dug round or over any mass of hard rock which thev
Came across, and in some cases they apparently
were stopped altogether by some such impediment;
nevertheless, the excavations represent great skill
and ingenuity, combined with a colossal amount of
physical toil.
A striking example of the magnitude of the work
done is shown in Figure 127 depicting an
artificial roofless passage-way from one part of the
mine to another. In the picture the cutting may
be seen immediately to the right hand side of the
standing figure near the centre.
Signs are not wanting that at a far
distant period the district in which the
emerald mines are situated was the centre
of a large industrious population,
probably chiefly devoted to mining opera-
tions.
Numerous buildings of this ancient
race still remain as lasting monuments of
skill, endurance and enterprise, as will
be clearly appreciated by the illustrations
which are here given. The purposes for
which they were erected can only be
surmised after such a lengthy lapse of
time, but many of them have the appear-
ance of having been forts and watch
towers, perhaps built to protect the mines
from invasion, whilst others may have
been dwelling-houses or barracks, and
some were certainly used as temples.
For the most part the edifices consist
of unshaped flatfish stones, closely packed
and arranged to form the walls, whilst
April, 1913.
KNOWLEDGE.
127
others are hewn out of the solid rock. There are
present a few examples of ancient masonry in which
the stones are cemented together with no little
skill, and there are also wells of considerable depth,
formed of stones closely cemented in a similar
manner.
A partly obliterated raised roadway or terrace
can be traced extending for a considerable distance
in the direction of the Red Sea.
A peculiar feature of the district is the presence
of a good many crudely formed obelisks, each
consisting of a huge roughly hewn mass of stone,
with somewhat smaller ones lying at the base.
It is probable that these once had some significance,
but with what intention they were erected none can
decide, although some think they answered the
purposes of signposts.
On the walls of some of the buildings, especially
on those of the temples, inscriptions are to be seen.
Those which have been deciphered, although of
great interest, do not help to solve the riddle of the
mines.
The interiors of the barrack-like buildings have
walled-up recesses surmounted by slabs of stone
slanting downwards from the apex. Immediately
below the apex is invariably to be found a stone
image of a god, placed there for some reason
connected with the religion of the departed race.
It is difficult to imagine a more wrild region than
the country surrounding these emerald mines, and
yet there is a majesty of beauty in the hideous bare
mountains, through which meanders a graceful
wadv of rock and coarse sand at almost everv
turn. (See Figure 124.)
With the exception of here and there an isolated
stunted tree, there is next to no vegetation. A few-
wandering Bedouin Arabs, ever in search of the
water, which they rarely find, form the only
inhabitants of this drear spot, which thousands
of years ago must have echoed with the hum of
busy slaves toiling to supply their rulers with a
useless gewgaw.
Dr. Max Bauer, in " Precious Stones," states that
gold and topaz are found in the range of mountains
in which the emeralds occur.
For information and the photographs the writer
is indebted to Mr. Edwin W. Streeter who
pioneered an expedition in the mines, and to Mr.
Allan Forster and Mr. F. Grote, two members of
his party.
TROMBIDOIDEA.
By CHARLES I). SOAR, F.L.S., F.R.M.S.
Naturalists, particularly those naturalists who study the
minute forms of animal life with the aid of the microscope,
have not paid much attention to the British Acarina. Why
the study of mites has been so much neglected in Britain
cannot be for want of specimens, for they can be found almost
anywhere. One reason may be on account of their minute
size, and the trouble that has to be taken to find them.
Another reason is, no doubt, the dearth of literature on the
subject. As yet we have only two monographs on British
mites, although there are a large number of papers distributed
about in the different natural history and microscopical
journals. There are several acarologists on the Continent
who are doing some splendid work with the mites, but they
are outside the Britannic area. Nevertheless, their papers
are very useful for the description and identification of what
mites we find here. The water mites found on the Continent
are nearly all found here in the British Isles, so it will no
doubt be the same with the land mites.
Except in the case of some of the families of the Sarcoptoidea
and Ixodoidea, there is nothing repulsive about the study of
mites, and they all exhibit a great variety of form and colour.
Their life-history is only known in a few cases, but we know by
experience what a great part they play in nature's economy.
The'Aj is plenty of original work waiting to be done, and it
would be worth doing. There are about thirty families of the
Acarina waiting for their history to be studied and written in
the British Isles. Two families have been done, and done
well, the Oribatidae and the Tyroglyphidae, by Mr. Michael,
F.L.S., both published by the Ray Society.
Let us just glance at the super-family Trombidoidea. This
is divided into six families : —
First, Trombididae, commonly called harvest mites. The
small, red, velvety mites we find on our garden borders belong
to this family. All the mites of this family are red, some
darker than others. The body is covered with feathered
hairs, according to the species. A monograph on the Trom-
bididae has just been published by A. Berlese. He has
divided the family into fifteen genera, and gives a coloured
figure of each type species. Dr. George, of Kirton-in-Lindsey,
has published some papers in The Naturalist on these mites,
but the subject is only begun as yet.
Second, Caeculidae. This is a small family of rather
large mites, found in moss, fallen leaves, and moist places,
rectangular in shape, and with very rough legs. They are
found in Southern Europe, but I have not yet seen any record
for Britain.
Third, Khyncholophidae. Several species of this family
have been recorded by Dr. George in The Naturalist, repre-
senting different genera. There was one particularly beautiful
mite, with plumes on the fourth pair of legs. It is known as
Eatoniana plumifer, and I think was found in Jersey. It
is common in Southern Europe and North Africa. I think
Dr. George's record is the only one for the British Isles.
Fourth, Cheyletidae. A small family of little mites. They
are distinguished by the enormous palpi attached to a distinct
beak. They are animal feeders, some predaceous, some
parasitic, divided into about eight genera. Two or three
species have been recorded for the Britannic area.
Fifth, Erythraeidae. Quite a small family, containing only
four genera. They are red in colour, quick in their movements,
and very erratic in their course.
Sixth, Tetranychidae. These are well known as the
red spiders. Several have been recorded for Britain. They
are divided into about eight or nine genera. The genus
Bryobia appears to be the most common.
The super-family Trombidoidea is a large one, and represents
with its six families a large number of genera, but it would
well repay anyone to take up any single family and work it
out.
THE DOUBLE (AND BINARY) STARS.
By F. W. HENKEL, B.A., F.R.A.S.
. Other Suns, perhaps,
With their attendant moons, thou wilt descry
Communicating male and female light,
Which two great sexes animate the World,
Stored in each orb, perhaps with some that live."
—Milton ("Paradise Lost," VIII, 148-152).
Though the Copernican hypothesis of the Earth's
motion round the Sun was immensely strengthened
by the discoveries of Galileo, and the Newtonian
theory of gravitation supplied the modus operandi
for this motion, yet the objection of the opponents
of Copernicus that the stars do not appear to move
as they should do in consequence of that motion,
long remained a serious difficulty. " Were the
Earth in motion in a mighty orbit round the Sun,"
said they, " spectators on our planet would, without
difficulty observe displacements in the relative
positions of the stars during the course of the
year, the nearer stars moving more and the more
distant ones less, just as objects in the surrounding
landscape appear to move when seen by a spectator
in a moving carriage." But no such motions could
be detected, and all that could be answered was that
the distances of the stars are so vast that the size of
the Earth's orbit is but an insignificant quantity in
comparison. It was no doubt partly on account of
his difficulty in accepting this explanation that
Tycho Brahe was led to reject the Copernican views,
since his observations had not enabled him to detect
any " parallactic " change of place due to the Earth's
supposed motion, and his measurements of the
apparent diameters of the stars had led him to con-
clude that the brightest of these objects would be of
enormous dimensions (greater than the whole Earth's
orbit) were the Copernican hypothesis true. After
the invention of the telescope it was seen that the
apparent diameters of the stars were very much less
than had been assumed to be the case by Tycho and
others and up to the present time the true diameter
of a star has never been measured, being less than
the minimum visible, the disc seen by the naked eye
being an optical illusion, an effect of irradiation.
Galileo, in one of his " Dialogues on the Systems
of the World," proposed that pairs of stars seen
close together in the sky should be observed and
their relative position noted and distance measured
throughout the year. If one of these objects be
nearer to us than the other, it will be displaced and
the angles and distances will change regularly in
that interval of time. The same idea was suggested
by others, but the first to carry out the suggestion
systematically was Sir William Herschel. The
latter, finding many cases where two or some-
times more stars lie close together in the sky,
and supposing the brighter component was
nearer to our system than the fainter one,
made numerous measurements, expecting to find
regular annual variations due to this supposed
difference of distance — in other words, parallactic
displacement.* But instead of finding this Herschel
detected a regular progressive change of quite a
different nature, showing sometimes that one of these
bodies was describing an orbit round the other, or
that both were travelling together throughout space.
In his own words he " went out like Saul to seek his
lather's asses, and found a kingdom " — the existence
of systems (of Stars) of a different and higher order
from that prevailing in our own system, binary
and multiple stars. A distinction was thus made
between stars optically connected which merely lie
nearly in the same direction, as seen from our planet,
but may be as far removed from one another as they
severally are from our system, and stars physically
connected — systems consisting of two or more
members moving round a common centre, or in
nearly parallel paths in a common direction. All
over the sky there are to be found cases of two or
more stars lying much closer together than the
average distances of the stars from one another, and
perhaps as many as twelve thousand such couples
are known, the double stars. Some of these doubles
have components of nearly equal brightness (e.g.,
the two components of a Centauri, the nearest of all
external celestial objects to our system, so far as is
yet known, and the two components of 61 Cygni,
the next nearest system — both of these are also
binaries) ; in other cases the members are of very
unequal magnitudes, like Sirius and its companion,
the former being the brightest of all the stars visible
to us, whilst the latter is only visible by the help of
the most powerful telescope, and was not detected
till 1862. In that year the late Alvan Clark first saw
it with the recently finished Chicago refractor, the
then largest instrument of its kind in the world.
Several hundred binary systems are now known with
more or less certainty, moving in elliptic orbits
round common centres, the orbits in some cases
being almost circular, in others very oval and
" eccentric." There are also systems of three or
more stars, the trinary and multiple stars. The star
£ Cancri consists of two larger and fairly close
members revolving in nearly circular orbits round
■■'■ Parallax is the name given to an apparent displacement of an object due to a real displacement of the position of the
observer. Technically, the parallax of a star is the angular value of the semi-diameter of the Earth's orbit (which is
greater as the star is nearer), as seen from the star.
128
April, 1913.
KNOWLEDGE.
129
their common " centre of gravity," with a third
fainter and more remote body, whilst e Lyrac con-
sists of two pairs of stars, and the multiple star
6 Orionis, not far from the centre of the great
Nebula, consists of four principal stars and two
minute companions very close to two of the brighter,
" to perceive both which is one of the severest tests
which can be applied to a telescope " (Sir John
Herschel), but three of the four brighter were detected
by Huyghens, in 1656. Though, as we have just
seen, the number of double stars known to modern
astronomers, and visible through the telescope,
is thus considerable, yet the angular distance
of the components is too small to admit of their
detection by the unaided eye in pre-telescopic days,
so that though a few clusters were known to the
ancients, the first double star which attracted
attention seems to have been £ Ursae Majoris, Mizar
in the Great Bear, which was noted as double by
Riccioli about the middle of the seventeenth century
(Lewis). This was also the first star to be photo-
graphed as double, by G. P. Bond, in 1857, and also
the first " spectroscopic binary," a class of objects of
which we shall hear more later on. It is curious,
too, that there is comparatively close to Mizar, which
is of the second magnitude, a faint star, Alcor, just
visible to the unaided eye, and it is said that the
Arabs considered its detection as a test for keen
eyesight. This star is said to be sometimes known
as " Jack bv the Middle Horse," Mizar being thus
the " Middle Horse " pulling " Charles' Wain."
Dr. Hooke, in 1665, discovered that y Arietis con-
sisted of two fourth-magnitude stars, eight seconds
of arc apart. During the eighteenth century the
well-known doubles, a Centauri, y Virginis, Castor,
61 Cygni, /3 Cygni, e Lyrae, a Herculis, and f Cancri
were added to the list. The latter star was discovered
by Christian Mayer, a Jesuit priest living at
Mannheim, and shortly before his death, in 1781, he
published a catalogue of all double stars known up
to that date, including his own additions, making a
total of eighty-nine pairs. For the first time he
hazarded the suggestion that some at least of these
pairs must be physically connected, a suggestion
fully confirmed a few years later. As already
mentioned, when first discovering and observing
hitherto unknown double stars, Herschel hoped to
employ them to determine parallaxes, but continued
the work with other ends in view. His first catalogue
contained two hundred and sixty-nine pairs, and its
examination by the well-known philosophical writer,
the Rev. John Michell, the " ingenious Mr. Michell "
as he is called by Mr. Lewis, led him to make the
following remarks. He says: "Thevery great numbers
of stars that have been observed to be double by Mr.
Herschel, if we apply the doctrine of chances, cannot
leave a doubt with anyone that by far the greatest
part, if not all, of them are systems of stars so near
to each other as probably to be liable to be affected
sensibly by their mutual gravitation, and it is, there-
fore, not unlikely that the periods of some of these
about their principals (the smaller ones being upon
this hypothesis considered as satellites to the others)
may some time or other be discovered." We may
assent to the conclusions, or rather to the probable
meaning of their author, without committing our-
selves to approval of his language. It was not,
however, till 1803 that Herschel made the definite
statement that some of these combinations were
indeed binary, in a paper which he contributed
to the Philosophical Transactions of the Royal
Society. This he justified by his examination of
the measures of Castor, y Leonis, y Virginis,
S Serfientis, and e Bobtis. Of seven hundred and
two double stars contained in Herschel's two
catalogues, the members were divided into six
classes according to their angular distance apart.
Class I contained 97 pairs separated less than 4".
Class II
102 .,
)»
from 4" to 8".
Class III ,
114 „
»)
„ 8" to 16".
Class IV ,
132 „
,,
„ 16" to 32".
Class V ,
137 „
»1
„ 32" to 60" (1')
Class VI ,
121 „
!»
over 60".
Since Herschel's day the whole subject of double-
star astronomy has been vastly extended, and our
knowledge greatly increased by the labours of a host
of professional and amateur workers. Amongst the
foremost of these must be placed the name of
F. G. W. Struve, of Dorpat, whose classic work,
familiarly known as the " Mensurae Micrometricae,"
still remains the standard authority " for method and
arrangement." This catalogue, published in 1837,
contains measures of two thousand six hundred and
forty pairs of stars, three fourths of the ten thousand
four hundred and forty-eight measures being made
by Struve himself without assistance, but during the
latter part of his work he had the assistance of his
son and other observatory assistants, " who entered
the readings and turned the dome, but made no
measures." These measures have been collected,
compared and discussed with much other information
relating to double stars in a volume by Mr. Thomas
Lewis, F.R.A.S., of the Royal Observatory, Green-
wich, published in 1906 (Memoirs of the Royal
Astronomical Society, Vol. LVI). Struve's work
comprised a general survey of the sky between the
North Pole and 15° -5 declination, about 0-63 of the
whole sky. His plan of work was (1) to discover
and catalogue double stars ; (2) to make micrometer
measures of them ; (3) to estimate the magnitude
and note the colours ; (4) to fix the places by
meridian observations. Between February 11th,
1825, and February 11th, 1827, he examined one
hundred and twenty thousand stars from the first to
the third magnitude, and found three thousand one
hundred and twelve double stars, whose distance
apart did not exceed 32".
Many of the double stars exhibit the remarkable
phenomenon of contrasted colours, but it has been
remarked (Proctor, " Old and New Astronomy,"
p. 783) that this is never the case when the two
130
KNOWLEDGE.
April, 1913.
adjacent stars are of nearly equal magnitudes, and it
appears to be the universal rule that when there is
a contrast of colour the tint of the fainter star lies
more towards the violet (more refrangible) end of
the spectrum than that of the other. Thus, the
brighter star being reddish or yellowish will have a
green or blue companion. Sir John Herschel, who
worthily continued his father's work, and also con-
tributed what he modestly calls his " mite" towards
double-star astronomy, has suggested that this com-
plementary colouration is " probably in virtue of that
general law of optics that when the retina is under
the influence of excitement by any bright light,
feebler lights, which when seen alone would produce
no sensation but of whiteness, shall for the time
appear coloured with the tint complementary to that
of the brighter." There are, however, difficulties in
the way of accepting this explanation in all cases,
and others are inclined to regard this contrast of
colours as being, in some cases at least, due to a
real difference in the physical nature of the stars.
However this may be, the beauty of the sights
visible to the telescopist is greatly enhanced by the
wonderful display of colours given by different
celestial objects. It is often found that if in a
double-star system the coloured star be much less
bright than the other, it will not affect the latter's
colour. Thus, for example, >/ Cassiopeiae is com-
posed of a large white star and a fainter one of a
" rich ruddy purple." A pleasing picture of the
curious alternations of illumination that would be
produced for the inhabitants of a planet circulating
round a pair of coloured double stars may be drawn,
and is given by Sir John Herschel (" Outlines of
Astronomy," p. 851). Suppose a planet revolving
round a red and and green sun. When the red sun
rises there will be daylight, and " all will be red."
Bye and bye the green sun will rise and mount
higher above the horizon. The light will gradually
change from a reddish tint to pure white. Later on,
the red sun will set, and the remaining illumination
will consequently be green. Last of all, the green
sun will set, and darkness will set in. Thus we
have the alternations red-day, white-day, green-day,
and night, the colours of all objects undergoing
corresponding variations.
It is a remarkable fact that though isolated red
stars are found in most parts of the sky, no decided
green or blue star has ever been noticed unassociated
with a brighter companion (Herschel).
We have already stated that the orbits of binary
stars round their centre of mass are ellipses, usually
much more oval than the planetary orbits in our
solar system, the average eccentricity of the visual
binaries being about 0-5 (See " Researches," Vol. II,
ch. 20), but it is a remarkable and interesting fact
that the closer " spectroscopic " binaries move in
much more nearly circular orbits. The application
of the spectroscope to stellar astronomy has not only
given us information otherwise unobtainable as to
the chemical nature of the heavenly bodies, but it
has also enabled us to detect hitherto unsuspected
motions, and has rendered known the existence of
bodies perhaps for ever invisible to our telescopes.
By means of this instrument it has been ascertained
that the number of binary stars is far greater than
anyone had previously imagined, but that in most
cases the components are too near together to be
separated by the most powerful telescope. Accord-
ing to estimates based on the work done at
the Lick Observatory, Campbell found that about
one star in five of those examined proved to be a
spectroscopic binary, and in certain groups this ratio
was found by Frost to be as high as one third (See).
The telescope discloses only the widely-separated
and luminous companions amongst the systems
nearest to us in space, but the spectroscope enables
us to detect all attendant masses which are large
enough perceptibly to disturb their luminous
" fellows," whatever be their distances, thus enor-
mously increasing our knowledge of stellar systems.
When a star is approaching us the dark and bright
lines in its spectrum are shifted slightly towards the
violet; when it is receding they are shifted in the
opposite direction, and by the comparison of well-
known lines thus changed in position with their
ordinary position as seen in terrestrial spectra it is
possible to determine the speed of their motion.
Thus, the well-known variable star, Algol, exhibits
changes in its spectrum indicating that the velocity
in the line of sight undergoes variations, being alter-
nately towards and away from the Earth, and thus
is confirmed the view that its variability is due to
partial eclipse by a revolving dark satellite, the
" stupendous dark globe." It has been shown, too,
that a Virginis, like Algol, has a massive dark com-
panion which, however, does not eclipse, as it does
not come between the star and our position. Other
double stars have been discovered in which both
components are bright, so that at one part of their
orbit the lines common to the spectra of the two stars
appear double and separated, gradually closing up
till the\- appear single and then opening out once
more. Since visual binaries with known orbits are
found to give variations of a similar character in
their spectra and have thus come to be included in
the class of spectroscopic binaries as well as "visual"
ones, but so far no spectroscopic binaries first dis-
covered as such have been resolved telescopically,
we see that the difference merely consists in the
smaller size of their orbits and consequent shorter
periodic times of revolution of the latter. Periods
of a few days, or even hours, are known for these,
whilst the shortest periods for a visual binary yet
known is that of f5 Equulei (5 • 7 years) and orbits
with periodic times of hundreds of years have been
calculated for some of the more widely-separated
binaries (y Virginis, 182 years; rr Coronae, 340 years,
Lewis). When the angular dimensions of the orbit
and the parallax of the system are known, the real
dimensions (in miles, kilometres, and so on) are
easily calculable, and from a knowledge of the
April, 191J.
KNOWLEDGE.
131
periodic time of revolution the total mass of a
binary system may be obtained from the extension
of Kepler's third law, assuming the motion due to
an action of a gravitative character. Let Mt and M2
be the masses of the two components respectively,
M and in the mass of the Sun and Earth.
Then
Mi + Mi =
R:1
-11
where T = Earth's period of revolution = 1 year and
R = the semi-axis major of its orbit, the astronomical
unit ; a and p being the semi-axis and periodic time
respectively of the stellar system. Thus our formula
becomes .,
Mi + Mt = -^r
P
giving the mass of the system in terms of the Sun's
mass as unity.* Thus we find the masses of many
of the binary systems are comparable with that of
the Sun, some being rather smaller, others consider-
ably greater.
Of fifty-three orbits of spectroscopic binaries dealt
with by Dr. See, he finds that the mean eccentricity
of these orbits is considerably less than that of the
visual binaries, being only 0-23 instead of 0-5, as
for the latter, a point which has important bearings
on Cosmogonic theory. The average period for
these fifty-three systems is about thirty-seven days,
but if we exclude a few long period stars, the
average period of all the rest is about ten days.
From the formula ,
M! + Ma = ~
p~
assuming the average mass of the spectro-
scopic binaries to be about the same as that
of the visual ones, and taking M1 + M2 = 1,
we find the average value of the mean distance
to be 0-2173 astronomical units, when p = 37
days or 0-09 when p = 10 days. Thus the average
dimensions of these orbits are less than that of
the planet Mercury, and it seems probable that
for such orbits the efficacy of tidal friction as
a possible agency in changing their forms may
not be overlooked. The late Sir George Darwin,
whose recent death we have to deplore, and whose
researches on the problems of fluid motion and tidal
friction generally are well known, was of opinion
that many double stars have been generated by the
division of primitive and more diffuse single stars, in
a manner somewhat analogous to that in which he
supposed that our own Moon came into being.
Many difficulties, not altogether ignored by Darwin
himself, prevent our acceptance of his views as
regards the origin of our satellite, but there appears
more reason to consider that the fission theory of
the origin of double stars is a true one. Such fission
would give rise to nearly circular orbits, and though
this is not the case with the known systems, it is
more true for the nearer spectroscopic binaries than
for the more widely separated visual ones. But it has
been shown that when two bodies of not very unequal
masses revolve round one another in close proximity
the conditions are such as to make tidal friction as
efficient as possible in transforming the orbits.
Hence we have in tidal friction a cause which may
have not only sufficed to separate the two component
stars of a double star system from one another, but
also to render the orbit eccentric (Darwin). Thus
it may be that under this influence in the course of
time the orbits of the spectroscopic binaries will
increase and become more eccentric, more nearly
like those of the " visual " binaries. On the other
hand, it is not impossible that some of these orbits
ma\' be shortening and becoming more nearly
circular under the action of the resisting medium,
whose long-continued action affords the best explan-
ation yet advanced of the comparative circularity of
the orbits of the planets in our own Solar system.
The efficacy of tidal friction (whose tendency is to
produce increase of eccentricity and distance) is
greater as the mass-ratios of the bodies acting and
acted upon are more nearly equal, as in the compo-
nents of a double star system, and least when one
mass greatly preponderates, as in our own Solar
system, where the mass of the Sun exceeds that of
all the planets put together more than six hundred
times. " The preponderance of high eccentricities
amongst the equal pairs seems to be an indication of
the higher efficacy of tidal friction, or of the lesser
importance of the action of a resisting medium in
such systems," and so, whilst deducing one confirma-
tion of the action of tidal friction and the resisting
medium from the small size and roundness of the
orbits of the spectroscopic binaries, we ma)' find an
additional verification of this theorv in the larger
eccentricities occurring amongst binary stars with
nearly equal components. We may, too, if we
please, derive important conclusions as to the relative
ages of the various systems. Thus from the
theoretical researches of Sir G. Darwin on tidal
friction, supplemented by the long imperfectly recog-
nised agency of the resisting medium, Professor See
has for the first time succeeded in giving a reasonable
account of many remarkable features in the phe-
nomena of the starry heavens, and has securely laid
the foundations and much of the superstructure of
a rational cosmogony. But there will always remain
" the immeasurable magnitude of the undiscovered "
to humble our pride ; and ever upward progress, we
trust, in our knowledge of the wondrous universe of
God, will not lead us to imagine that we have
" solved the universe."
The Earth's mass being only .i^oVtttt that of the Sun, is here neglected.
SOME NOTES ON THE ANIMAL LIFE OF
BLAKENEY POINT.
By WILLIAM ROWAN.
Figure
Blakeney Point needs no further description after
Mr. Grew's article in the January issue of this
Journal. One might repeat again, however, that
" the Point " is the extremity of a shingle spit, some
eight miles in length. It
is separated from the main-
land by the " Blakeney
Channel," and is a sail, at
high tide, of over a mile
from Morston.
The birds being the most
noticeable feature of the
animal life, we are descri-
bing them first. As might
be expected, few of the
species found in the sum-
mer are found in the winter,
while in the autumn and
spring many rare migratory
birds pay a fleeting visit.
Should you visit the Point in summer, you would
notice that as you approach it birds rapidly get
more numerous. Thev all appear to be of one kind
— the common tern (see
Figure 133).
If you are an ornitholo-
gist, however, you will soon
notice that mingled with
these is a considerable
sprinkling of the lesser
tern. They are fishing all
around, and time after time
you see a bird dive into
the water, rise with a little
fish in its beak, and dis-
appear over the dunes.
They all seem to go in
the same direction, and
even when the shoal of frv.
on which they are feeding,
has gone out with the tide
you notice stragglers
making their way over
interest
- ?
Figure 133. Tl
the
If your
you also
dunes,
has been sufficiently aroused,
take the same road on landing. As you climb
up the side of the dunes all is quiet. You may
put up a dotterel with her little chicks, or bolt
a rabbit, but that is all. But as you reach the crest,
and catch a first glimpse of a long shingly beach,
with the open sea beyond, a cloud of birds rises in
the air. The noise is terrific, and as vou climb
down the other side to get a nearer look, and walk
underneath the great whirling mass, one bird after
another with an earsplitting shriek makes a desper-
ate swoop at your head. It is merely show, how-
ever, and you need fear no injury.
And so vou have made the acquaintance of the
noisiest and most important
inhabitants of the Point.
Their nests are strewn all
over the shingle on the
seaward side of the dunes.
If your visit be in July,
you will see many voung
already running about.
They almost invariably
crouch when you approach,
and are often hard to sec.
Apart from their size,
their black chin distin-
guishes them at once from
the young of the lesser tern
(see Figure 132). The
eggs vary enormously in size, ground colour and
markings. Fggs at the two extremes of the scale
are often found in the same clutch. About the use
of material for nest-build-
ing there seems to be no
definite law. As a rule,
materials are used when
they are handy, and only
when they are. For in-
stance, of all the nests
examined last summer on
the drift line, in only one
case had the birds de-
posited their eggs without
•collecting material on
which to lay them. In
one case the " nest " was
eighteen inches across. On
the open shingle one must
be constantly on the qui
vive to avoid stepping on
to the eggs.
In the centre of the colony vou will find nothing
but the eggs and young of the common tern. The
birds resent the intrusion of any stranger in a practical
way. Even the rabbits have to keep clear of those
dunes that the terns occupy. On the outskirts of
the colony you will, however, find the lesser tern.
The nests of this bird are not crowded together like
those of the former, and you will only find them on
the Point in one kind of shingle, composed of verv
small stones and sand. This is in the main found
immediately above and below the highest tide limit.
Common Tern.
132
April, 1913.
KNOWLEDGE.
133
so that in certain years, as in 1911, when there was
an exceptionally high tide in the end of June,
hardly a young bird was hatched out. That year
the colony consisted of some sixty pairs, or probably
more. The lesser tern is almost as bold as its larger
relative. The male is generally supposed not to
incubate the eggs.
Figure 1.52, however,
shows him in the act.
with his wife waiting
for her turn. Three
is usually stated to
be the average num-
ber of eggs, but some
forty-five nests exam-
ined the maximum
number found was
two.
Another bird found
nesting in some num-
bers, though it lays
earlier than the terns,
and is resident the
year round, is the little
ringed plover (see Figure 134). You find its eggs
chiefly behind the dunes (see Figure 135), and in
small sheltered lows. The birds seem to object to the
exposed shingle. They are extremely shy, and to
secure a photograph of one needs the exercise
of considerable
patience. Other
birds that are found
nesting are larks,
pipits, wagtails, red-
legged partridge,
sheld-duck and one
pair of oyster
catchers. Last year,
for the first time,
there were two.
All the common
gulls are well repre-
sented, though none
nest. Other sea
birds pay short
visits
the summer
Should your visit
fall in the winter
months, you would
find the Point very
different. With the
exception of a few gulls flapping over lazily from
the mainland, no birds come near the boat as you
cross. When vou have landed you find that the
shingle, so noisy and full of life in the summer, is
now deserted rind the marshes arc the scene of
activity. Should you hide and watch them with a
pair of binoculars, you will soon notice that the
waders predominate. The commoner species are
curlew, dunlin, sanderling and ringed plover, with
an occasional redshank, while knot occur in vast
Figure 134. The Ringed Plover.
throughout
FIGURE 135. Fggs of the Ringed Plover
flocks, sometimes numbering over one thousand.
Larks and linnets feed in the marshes in great
numbers. The gulls, again, are well represented on
the beach, though now may be seen an occasional
huge glaucous gull. If the winter be a severe one,
however, the bird life is swelled by a huge army of
ducks and geese.
Among the former,
widgeon, mallard and
sheld are the com-
moner. Among the
latter, brent, pink-feet
and barnacles. In the
late autumn the swan
is not an uncommon
sight, while the great
northern black-
throated divers are of
regular occurrence.
Of the mammals,
the rabbits are by far
the most numerous.
In summer time, when
the long evenings
draw gently to a close, the Point seems to swarm
with them. Old and young are all out then, taking
their supper in the marshes or on their moss-grown
margins. As you stroll quietly along between these
and the dunes, one rabbit after another bolts across
your path, heading
for safety to its
burrow. If you turn
off now to the side,
and make for the
marsh, many more
bolt past you, till
you reach their
feeding ground.
The first thing that
catches your eye is
their well - marked
runs, reaching right
away to where the
tide is softly creep-
ing up (see Figure
137). Everywhere
you see Aster tri-
polium eaten. Its
succulent leaves are
not as salt as one
might imagine. On
the edges the
Suaeda bushes are also bitten, in some cases to
the ground. Still further in, towards the dunes,
Convolvulus soldanella, covering large areas of the
firmer ground, is also badly attacked.
On the crest and seaward side of the dunes are a
few burrows, but they are a mere sprinkling com-
pared with those on the other side.
Were it not for numerous tracks, one would at
first suppose in winter time that the rabbits had
gone, for you see none of them. Day breaks at
w^^m
134
KNOWLEDGE.
April, 1913.
about seven or soon after, and it is certain that there
are no rabbits about then. But if you search care-
fully, you will find many tracks, freshly made; for
the rabbits have been out earlier than von. In the
Figure 136. Glaux Lagoon.
evenings, too, they only come out after dark, when
you have made yourself comfortable in your tent.
Their food remains much the same now as in the
summer. One interesting addition to the list must
be mentioned, however. In the Glaux lagoon (see
Figure 136), now filled with water, there are con-
siderable patches of sand dug up by rabbits. The}*
are plainly seen on this photograph, showing up
dark. It was some time before the cause of this
nightly exercise was found, but it eventually proved
to be that the rabbits dug up the ground to reach the
Glaux rhizomes for eating.
Rats are, unfortunately, quite abundant on the
Point. Since the stranding of a whale on the
beach, in the fall of 1910, they have been there.
In 1911, they were present in such numbers and
harrassed the terns so seriously, that these laid
an extraordinary number of mis-coloured and
mis-shapen eggs. Since then poison and traps
have been kept on the go incessantly, but still
they are there. This winter their tracks were
wonderfully abundant round the tents. They live
chiefly in the rabbit burrows.
As harmful as the rats are the two small colonies
of stoats, which are now, however, almost at the
point of extinction.
At least one kind of vole occurs, and as casual
Figure 137. Rabbit runs in salt marsh.
visitors seals must not be forgotten, for the}- often
turn up and spend a few days on the Point. As
many as seven have been seen at the same time.
THE ROYAL INSTITUTION.
A GENERAL MEETING of the Members of the Royal Institution
was held on the afternoon of March 3rd, Sir James ("richton-
Browne, Treasurer and Vice-President, in the chair. Mr.
T. W. E. Davenall, Mr. 1'. M. Deneke, Mr. H. Trevelyan
George, Mr. H. G. Gillespie, Mr. \V. V. Graham, Lady Heath,
The Hon. Marguerite de Fontaine Drever Joicey, Mr. J. A.
Law, Rev. J. Marchant, Dr. W. A. Milligan, Mr. D. W.
Moncur, The Hon. Mrs. R. Parker, Mrs. Carson Roberts, and
Miss Tatlock, were elected Members. The Honorary
Secretary announced the decease of The Right Hon. The Earl
of Crawford, Mr. George Matthey, and Sir William H. White,
Members of the Royal Institution, and Resolutions of con-
dolence with the relatives were passed.
The following are the Lecture Arrangements at the Royal
Institution, after Easter: — Dr. A. S. Woodward, Two
Lectures on Recent Discoveries of Early Man. Professor VV.
Bateson, Fullerian Professor of Physiology, Two Lectures in
continuation of his before Easter course on The Heredity of
Sex and some Cognate Problems. Professor W. Stirling,
Three Lectures on Recent Physiological Inquiries: 1, Pro-
tective and other Reflex Acts ; 2, Equilibrium and the Sixth
Sense; 3, Ductless Glands and their Dominating Influence.
Professor T. B. Wood, Three Lectures on Recent Advances
in the Production and Utilization of Wheat in England. Dr.
E. Frankland Armstrong, Two Lectures on l,The Bridge into
Life; 2, Colour in Flowers. Professor J. Garstang, Three
Lectures on The Progress of Hittite Studies: 1, Recent
Explorations ; 2, Religious Monuments of Asia Minor ; 3, Cults
of Northern Syria. Mr. Edward Armstrong, Two Lectures on
Florentine Tragedies : 1, The Exile of Dante; 2, The Burning
of Savonarola. Professor W. J. Pope, Three Lectures on
Recent Chemical Advances: 1, Molecular Architecture; 2,
Chemistry in Space ; 3, The Structure of Crystals. Mr.
A. M. Hind, two Lectures on 1, Van Dyck and the Great
Etchers and Engravers of Portrait ; 2, Rembrandt's Etchings.
Professor Sir Walter Raleigh, three lectures on 1, Boccaccio ;
2, Mediaeval French Novelists; 3, Chaucer. Mr. H. A.
Humphrey, two lectures on Humphrey Internal Combustion
Pumps. Professor E. Rutherford, three lectures on Radio-
activity : 1, The Alpha Rays and their connection with the
Transformations ; 2, The Origin of the Beta and Gamma
Rays and the connection between them ; 3, The Radio-Active
State of the Earth and Atmosphere. The Friday Evening
Meetings will be resumed on April 4, when Mr. James J.
Dobbie will deliver a Discourse on The Spectroscope in
Organic Chemistry. Succeeding Discourses will probably
be given by Mr. C. J. P. Cave, Dr. T. M. Lowry, Professor
J. Garstang, Mr. H. G. Plimmer, and other gentlemen.
THE INFLUENCE OF AGE ON THE VITALITY AND
CHEMICAL COMPOSITION OF THE WHEAT BERRY.
Bv K. WHYMPER.
{Continued from page 90.)
Table 23.
Analyses of some Old Samples of Wheat.
the various ages examined, the moisture content
should show considerable fluctuation.
Ash.
Just as moisture in wheat and flour is a variable
according to the conditions of storage, so may also
the ash content of wheat be found to vary according
to the soil in which it is grown.
Wheat as a general rule varies in ash content from
two per cent, to about one per cent, below which it
is extremely unlikely to fall.
It is, therefore, of considerable interest to notice
that there is a gradual decrease in mineral matter
with age, with the exception of the 185.3 wheat
which contains a slightly higher quantity than that
of 1854, and which, in other particulars does not
seem to fall into line with the wheats according to
its age.
Snyder {Bull. 83 Agric. Expt. Stn. Univ.
Table 24. Composition of Flours and other Milling Products of Wheat.*
Mummv
Rothamsted Wheat.
Rivet
Wheat
Estim.
1500 B.C.
1852
1853
1854
1911.
%
%
%
%
%
Moisture ...
10-69
16-54
8-32
12-68
12-10
Ash
0-68
0-90
0-83
1-14
2-04
Fat or Ether
Extract
1-71
2-98
1-83
1-66
2-51
Nitrogen
1-686
1 • 799
1-915
1 • 549
2-023
Proteid (Nx6-25)
10-54
11-24
12-12
9-67
12-64
Soluble Carbo -
hydrates
3-68
3-46
5-16
5-16
4-04
Starch
68-18
60-0
68-72
66-13
66-24
Husk or Fibre ...
1-50
1-62
1-70
1-61
1-78
Acidity (taking the
1911 sample as
Unity)
2-6
1-1
0-7
1-6
1-0
Aciditv (taking
Milling Product.
Water.
Proteid
Nx 5-7.
Fat.
Carbo-
hydrates.
Ash .
the wheat ground
in the Laboratory
as Unity.
Nitrogen.
%
First Patent Flour ...
10-55
11-08
1-15
76-85
0-37
0-44
1-9435
Second Patent Flour
10-49
11-14
1-20
76-75
0-42
0-44
1-9544
Straight or Standard Patent Flour
10-54
1 1 • 99
1-61
75-36
0-50
0-50
2-103
First Clear Grade ...
10-13
13-74
2-20
73-13
0-80
0-67
2-410
Second Clear Grade
10-08
15-03
3-77
69-37
1-75
1-50
2-636
" Red Dog " Flour ...
9-17
18-98
7-00
61-37
3-48
3-27
3-33
Shorts
8-73
14-87
6-37
65-47
4-56
0-72
2-608
Bran
9-99
14-02
4-39
65 • 54
6-06
1-27
2-459
Fntire Wheat Flour
10-81
12-26
2-24
73-67
1-02
1-72
2-150
Graham Flour
8-61
12-65
2-44
74-58
1-72
1-00
2-219
Wheat ground in Laboratory
8-50
12-65
2-36
74-69
1-80
1-00
2-219
Chemical Examination.
Moisture.
The percentage of moisture found in wheat is a
very variable quantity. In a personal letter from
Mr. Humphries the figures for English wheat grown
last year were given, and showed on an average
fourteen per cent of moisture in October, 1911. In
February, 1912, the moisture content had risen to
eighteen per cent., and in June, had fallen to
approximately sixteen per cent. Similar experience
has of course been the lot of every miller, and there-
fore it is not surprising to find that, in the wheats of
Minnesota, 1904) found that the percentage amount
of ash in different wheat crops varies but little from
year to year, and that flour made from fully matured
wheat has a minimum ash content because high
maturity is usually accompanied by a low ash.
This fact is forcibly borne out by the results
obtained with the wheats of different ages examined
by the present writer.
Fat or Ether-extract.
A specially dried Ether was prepared for these
estimations and the figures may be taken as those of
actual fatty matters extracted.
"Studies of Bread and Bread-making at the University of Minnesota in 1899-1900, by Harry Snyder, B.S., Washington, 1901.
135
136
KNOWLEDGE.
April, 1913.
It was with considerable surprise that 1-71 per cent,
of Ether-extract was taken from the Mummy Wheat
when compared with 2-51 per cent, from an English
wheat harvested in 1911. The figures have, how-
ever, been carefully checked and confirmed.
Wheat oil very rapidly undergoes decomposition
on exposure to air, De Negri finding that a sample
after being kept for one year contained nearly half
its weight of free fatty acid calculated as Oleic acid.
Balland (Compt. Rend. 190.5, CXXXVT, 724)
obtained some sixteen parts of Ether-soluble fatty
acids with eighty-four parts of true oil from one
hundred parts of fatty matter extracted by Ether
from freshly-milled flour, whilst an older sample of
flour gave fatty matters containing only eighteen
per cent, of true oil with eighty-two per cent, of
mixed fatty acids.
It is apparent, therefore, that quite a large propor-
tion of the fatty acids obtained from wheat oil is
soluble in Ether, a fact which accounts for the
unexpectedly high figures obtained for fatty matter
extracted by Ether from the Mummy Wheat.
There may also be a small quantity of bitumen
included in the Ether-extract from Mummy Wheat.
Nitrogen and Proteid Matter.
The quantitative changes which the wheat has
suffered during storage are comparatively insignifi-
cant, and such differences as are found may be said
to fall within the limits for normal wheats of
different varieties.
The nature of the changes undergone by the
proteid matter, however, is striking in the case of the
oldest wheat but quite unworthy of consideration of
those grains up to fifty years of age, as has already
been shown when the gluten strength of the crushed
wheats under examination was discussed.
The process of decomposition of the wheat gluten
is mainly biological, in that bacteria play a very
important part both in oxidising the actual nitro-
genous matter and in producing acids from the other
components of the grain capable of degrading the
gluten.
It is certain that under normal atmospheric and
humidity conditions neither bacteria nor fungi could
obtain a good hold on the wheat berry, but that,
after the passage of a number of years, when the
outer protective covering of the grain had itself
become oxidised and permeable, the process of
decomposition would proceed more rapidly within
the grain.
The period of time necessary to bring about these
internal changes is entirely dependent upon the
conditions under which the wheat was stored.
There are other factors which have been shown by
various experimenters to have marked effect on the
physical characteristics of gluten, and which may be
more or less responsible for the reduction in the
gluten strength of the flour obtained from the
Mummy Wheat.
The degrading effect of acids has already been
mentioned, and the results obtained by Snyder
would prove that a flour of higher acidity is less
efficient for bread-making, owing to a lack of strength
which results from a pronounced decrease in gliadin
percentage.
The differences of opinion between Snyder and
Wood and others are mainly as to which is " the
cause " and which is " the effect " of acidity ; though,
for the purposes required here, it is sufficient to
notice that with increase of age there is greater
acidity, and, in the extreme case, a complete loss of
gluten strength.
The influence of mineral salts on gluten strength
determined by Wood is of great interest to the baker
and miller and in cases where the flour is made into
dough with water. The general action of salts is
that of coagulation or binding and toughening the
dough, and often overcomes the degrading influence
of an acid when both salt and acid are present.
Lactic acid of all strengths was found by Wood to
reduce the wheat gluten strength, and that propor-
tional increases in the quantity of added salt to
procure cohesion of the dough were then necessary.
In the case of a normally air-dried whole wheat,
however, the circumstances are different, and, with
the exception of the mineral matter held in immedi-
ate juxtaposition to the proteid matter, the salt
solutions can have little effect seeing that, under
fairly constant conditions of temperature and
humidity, " flow " does not exist to any extent and
that such effect as is produced is purely local.
In the process of time the action of the self-
contained salts may have effect on the gluten, and it
is clear from the results obtained by the present
writer that sixty years is, under normal conditions,
too short a period to allow any appreciable degrada-
tion of gluten to take place w ithin the wheat berry.
This may be explained by the fact that the salt
content of the newer wheats is still high enough to
counteract the degrading effects of the acids as they
form, and that, as age increases and the salt content
of the berry falls, the full influence of the accumu-
lating acids gradually becomes more apparent.
Carbohydrates- — Soluble — and Starch .
The slight decrease in the Soluble-carbohydrates
with increase of age is noticeable though without
importance, whilst the starch content of all the wheats
examined is constant within the limits of experiment
and natural variations when the differences of
moisture and proteid matter are taken into account.
The starch and fibre are undoubtedly the most
stable of all the components of wheat, and the
granules of starch from even the oldest samples do
not show pitting due to enzymic action, a fact which
adds further proof to the suggestion that the flow of
solution within the berry was restricted, owing to
lack of moisture.
Hush and Fibre.
The percentage of husk and fibre is practically
constant in all the samples of wheat examined.
April, 1913.
KNOWLEDGE.
137
In the case of the Mummy Wheat the fibrous
nature was completely lost and the friable powder
resulting from the crushed husk was as though the
oerries had been roasted.
Acidity.
The acidity of the samples lias already been fully
discussed under former headings.
Diastatic Power.
With the exception of that from the newest wheat
the aqueous extracts of all the samples examined
failed to render starch soluble. It should be of
importance to determine the connection between
" loss of vitality " and " diastatic power."
In a letter from Mr. Humphries it is stated that
wheat more than fifteen months old is rarely used in
commerce, and, consequently, the changes which
have been found to take place within the berry after
a period of fifty or more years are not likely- to be
encountered by the practical miller.
The chemical and physical alterations which
take place within the wheat grain, however, are the
same, only to a much more retarded extent, as
those which flour undergoes during storage, and they
mav, therefore, be taken as a guide for the latter
purpose.
Flour improves, in most respects, from the bread-
making point of view over a period extending for
about two months, but beyond this limit there will
be a deterioration, more or less rapid according to
the quality and conditions of the flour and the
conditions of storage.
Evaporation of moisture will be in proportion to
the amount of heat occurring during storage, and the
giving out and taking in of moisture are the prime
factors which influence the changes, biological and
chemical, which take place within the flour.
Balland (Contpt. Rend. CXIX, 565) found the
variations in chemical composition of flour during
storage, for a range of over two thousand samples, to
be principally due to fluctuations in moisture content,
which reached a maximum in February of about 16-2
per cent., and a minimum in August of 9 • 40 per cent.
The lowest percentage of acid was found by the
same author to be 0-013 per cent, in January, while
samples drawn in August contained nearly three
times that amount.
Humphries, in his researches on the conditioning
of wheat (Brit. Assoc, 1911), points out that the
mere addition of moisture to Southern Plate wheat
was not sufficient to produce a marked change on
the baking qualities of the resulting flour (this flour
contained fourteen and a half per cent, of moisture),
but that great improvement was noticed if the flour
was also conditioned by addition of further water
until it contained fifteen and a half per cent, of water.
Humphries observed that the improved Hour
showed a marked diminution in acidity (a statement
certainly not in accord with expected results, unless
the additional percentage of moisture had not been
taken into account), and a decrease in the percentage
of ash.
The production of inorganic phosphate by the
addition of water was believed to be the chief
cause of improvement.
In the light of Wood's experiments on the influ-
ence of salts on gluten, the perpetual though slow-
passage of a saline solution, such as that of a
phosphate, through the cells of the wheat berry or
in flour during storage, would undoubtedly tend to
retard the degradation of the gluten, which we
find to have taken place only in the most ancient
wheats and which is principally due to the formation
of acid, and to improve the gluten of a flour by
increasing the ratio of conditioning salt to degrading
acid.
The moisture content is the greatest variable,
whilst acidity always increases with age, the period
of time taken to produce absolute "inefficiency" of the
gluten being greatly retarded by the presence of salts.
The passing of the moisture in and out of the
flour or grain makes it possible for these changes to
take place, and the extent of the alternations
determines the rate of change.
Changesdueto enzymic action undoubtedly proceed
when the water content of the samples is high, such
as is seen, for instance, when sufficient moisture is
present to induce germination*, and it would be
interesting to observe the minimum amount of
moisture that would be necessary for such process.
It is quite certain, however, that, in the conditions
under which the examined wheats existed, this
point was never reached.
The minimum moisture content necessary to
maintain life within the seed is another interesting
figure to consider, and lies between fifteen per cent,
and forty-five per cent, in the case of wheat if the
action of bacteria and moulds be prevented.
In order to obtain this limiting figure, and also
with a view to furthering the present knowledge of
vitality and its duration in seeds, a number of
experiments have been undertaken with the hope that
the future examination of them may throw some
certain light on the conditions that influence the
retention of life within the seed. A full description
of these experiments and the objects for which they
have been undertaken have been reserved for a later
paper, when a complete discussion on their import
can be made.
Summary.
The influence of age on wheat grains is not very
pronounced when measured by chemical analysis,
the principal change which occurs being a marked
decrease in the ash content.
This fact, which has been noticed previously by
other experimenters, is mainly brought about by the
absorption and expulsion of moisture under changing
conditions of the atmosphere, whereby the soluble
mineral matter is brought to the surface of the grains
and, sooner or later, rubbed off.
Whymper (Internal. Conn, App. Clwni. 1009).
138
KNOWLEDGE.
April, 1913.
Increase of acidity with age is another change of
importance, and it has been shown that the combin-
ation of the loss of mineral matter with an increase
in acidity is largely responsible for the degradation
of the gluten, which shows itself when the "strength "
of the gluten is tested physically. There is no
pronounced decrease in nitrogen content attending
this physical change.
The chemical analysis of a wheat about three
thousand years old does not show any pronounced
variation from that of a new wheat except in these
two items.
Nor is this of great importance when vitality is to
be considered, for the bulk of the grain, the endo-
sperm, is without life, and is only called upon to
support life when germination has commenced. On
the other hand, it must not be forgotten that the
close proximity of the endosperm to the life-contain-
ing embryo must result in changes such as loss of
moisture, being mutually felt.
When the wheat grains are examined microscopi-
cally it is apparent that those of greatest antiquity
have suffered considerably at the hands of time, and
that the cementing material which binds the bundles
of starch together within the endosperm has decom-
posed, with the result that when such grains are
crushed they break up into minute, sharp-pointed
fragments, entirely different in appearance to those
from newer wheat.
When wetted the dough produced from the flour
of the oldest wheat is entirely without " strength," a
fact which has been shown to result from a combina-
tion of changes, chemical and bacteriological, taking
place within the berry.
It is striking that such a degradation of gluten is
not noticed also in wheats of fifty years of age, but
it is probable that no complete action can take place
within the grain until the tough integument has been
oxidised or otherwise rendered permeable to air and
bacteria.
The suggestion that the vitality of wheat or of any
seeds, depends upon the degree and rapidity of desic-
cation and the thickness of the integument is strongly
confirmed ; and the loss of moisture, either if too
rapid or extended over too great a period of time,
would tend to render the protective coating of the
seed pervious at a rate more or less rapid according
to the efficiency of the integument. On the other
hand, the cause of the loss of vitality of wheat in
ten years, which is the period recently given by
Carruthers and previously by others, must be exam-
ined more closely, for neither chemical nor micro-
scopical examination shows that there is sufficient
reason for the loss of vitality on these grounds
alone in so short a time.
For this reason a number of experiments covering
a wide range of environmental conditions has been
undertaken.
The experimental tubes, which have been prepared
in triplicate, will be examined in ten years' time, and
later at periods of ten years' interval if the first
results should justify such a procedure.
A description of these experiments has been reser-
ved for a later occasion.
In conclusion, I should be glad to express my
thanks to Mr. Paddison who has so admirably
prepared the photomicrographs for this research,
to Mr. W. A. Davis for supplying me with the
wheats of the years 1852 to 1854, and to my uncle,
Mr. Charles Whymper, for the specimen of Mummy
Wheat, the genuineness of which he has proved
both to his and my own satisfaction.
Mr. A. Bradley has assisted me not a little in the
practical side of this research, and especially in
preparing the tubes and samples for future
examination.
A HORSE AND COW IN HARNESS TOGETHER.
Oxi-:n are still well
known in most countries
as beasts of burden, and
horses, in spite of motor
cars, ma}' yet remain a
little longer with us ; but
here we have in double
harness not an ox, which
would be strange enough,
but a milch cow yoked
with a horse in the hay
field.
The photograph, from
which Figure 138 has
been made, was taken in
the summer of 1909 on
the golf links at Carls-
I'rom a photograph by
Figure 138.
A Horse and Cow in double harness.
/.. J. ll'iiitct-Joyiier.
bad, and the cow as
every-day partner in the
team did not appear to
receive anything but the
kindest treatment. A
great deal of the work of
picking up the haycocks
was done by the women
with the baskets, one of
whom appears in the
illustration.
Thus the women, and
not the team, did most
of the work on the links
by bringing their loads
on their backs from
various parts of the links
to the cart.
THE FACE OF THE SKY FOR MAY.
Bv A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 25.
Date.
Sun.
R.A. Dec.
Moon.
R.A. Dec.
Mercury.
R.A. Dec.
Venus.
R.A. Dec.
Jupiter.
R.A. Dec.
Uranus.
R A. Dec.
Neptune.
R.A. Dec.
Ceres.
R.A. Dec.
Pallas.
R.A. Dec.
Greenwich
Noon.
May i
,, 6
,, 16
,, 21
h. m. o
2 32*3 N.i5-o
251-5 i6'4
3 io"9 1 7 "8
3 30*6 J.9'0
3 50-5 20"I
4 ]o"6 21 'i
4 30*9 N.21'9
h. m. 0
23 io'i S. 7*0
2 54 '2 N.20-4
7 48*2 N.26'o
12 17*6 S. 2*2
l6 52'2 S. 27-4
21 27*0 S. i8"7
1 3'3 N. 8-4
h. m. 0
0 57*5 N 3-0
1 22'4 56
i 50-6 3'6
2 22*4 12 'O
2 58'! >5"5
2 384 19*0
4 22'7 N. 22'0
h. m. °
1 46*7 N. 15-7
1 39 '4 13-8
1 35*5 ft
1 35-4 io'9
1 38*7 io"a
1 45-0 9-9
1 54'oN.io"o
b. in. 0
19 I7"2 S.22"2
19 17-3 22*2
19 I7'I 22*2
19 i6'5 22*3
19 15-7 22'3
19 14*5 22\|
19 I3'0 S.22"4
b. in. o
20 40*3 S, i9'u
20 40*4 19O
20 40*5 19*0
20 40-5 ig'o
20 40*4 19*0
20 40 '2 19*0
20 39 '9 S. 19*0
h. 111. c
7 40*7 N.21 '0
7 41-1 2o'g
7 41-5 20 '9
7 41-9 20-9
7 42 '4 20-9
7 43-0 20-9
7 43-5 N.20'9
b. m. c
15 49-9 S.i 1 -7
15 45-6 1 1 -7
15 41-1 11*7
15 36-4 11*7
15 3,-7 1 1 '7
15 27-2 11 '8
15 22*9 S.iry
h. in. 0
14 48-0 N237
14 43-9 ^4-4
M 39'9 a5*o
14 36-2 25-3
14 32'3 25*6
14 29-8 25-6
14 27*2 N25-6
Table 26.
Date.
Sun.
P B L
Moon.
P
Jupiter.
P B h h T T
12 12
Greenwich
Noon.
May 1
00 0
-24-3 -4-0 224-4
23'3 3'5 I58"4
22*1 3'0 92*3
2o'8 2"4 26*1
19-3 1*8 320*0
I7'7 1-2 253-8
-15-9 -o-6 1S77
-21-4
-ii-8
+ 9*8
+ 21-8
+ 6-3
-17-1
— 21*1
0 » 9 ° h. m. h. in.
— 9*0 — 1 -7 50*0 1-4 0 47 m 9 S' e
9-0 1-7 119-8 33*1 6 33 e I 9 ttt
9*0 1 '6 189*7 04*8 6 48 nt 8 7 f
8*9 1 '6 2597 96*6 2 44 e 9 19 111
8*3 1 '6 329*7 128*5 0 49 e 8 26 m
8*7 i"6 39*8 160*4 i 4 tit 5 29 e
— 8*5 —1*6 i«9'9 *92'4 6 50 <r 6 41 ;//
6
„ 16
,, 26
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Jupiter Lx refers to the
equatorial zone, L2 to the temperate zone, Ti, Ta are the times of passage of the two zero meridians across the centre of the
disc ; to find intermediate passages apply multiples of 9h 50jm, 9h 55^m respectively.
The letters m, e, stand for morning, evening. The day is taken as beginning at midnight.
The Sun continues his Northward march. Sunrise during
May changes from 4-34 to 3-51 ; sunset from 7-20 to 8-3.
Its semi-diameter diminishes from 15' 54" to 15' 48". Out-
breaks of spots in high latitudes should be watched for.
for Southern observers. Illumination one-half on 1st, full on
31st. Semi-diameter diminishes from 3i" to 2i".
Venus is a morning star, at greatest brilliancy on 31st,
li° North of Moon on 4th. Semi-diameter diminishes from
Mercury is a morning star till end of month, well-placed 29" to 19". At end of month 0-3 of disc is illuminated.
Table 27. Occultations of stars by the Moon visible at Greenwich.
Disappearance.
Reappearance.
Dale.
Star's Name.
Magnitude.
Mean Time.
Angle from
N. to E.
Mean Time.
Angle from
N. to E.
1913-
h. in.
li. m.
May 2
Mars
—
7 19 in
46 °
8 45 hi
2.;j°
,, 10
47 Geminornm...
56
7 5"'
103
8 41) .■
289
,, 10
BAC23S3
65
10 16 e
55
10 49.'
354
., 13
34 Lconis
6-4
u 22 e
89
0 9*»i
35u
„ 16
BAG 4261
6-9
8 15,
203
—
„ 17
BAG 4306
6-9
2 3 hi
137
—
—
„ 17
Spica
I '2
4 39 <;
545
., 17
BAC453I
60
10 2 e
176
10 46 a
253
,, 20
BAG 5m
63
1 55 '"
'?.;
3 2 111
268
» 23
Lacaille 7730
7'0
-
—
0 57 111
269
„ 23
Lacaille 7759 ...
7-0
—
—
2 39 "'
276
,, 26
t/) Gapricorni
5'3
2 41///
44
3 57 '"
265
The asterisk indicates the day following that given in the Date column.
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
The occultation of Mars takes place in daylight, but from experience of a similar phenomenon I know that its observation will
be possible with (say) a six-inch telescope if the weather is good. The occultation of Spica is also in daylight and as the Moon
will have just risen it will be difficult to observe.
139
140
KNOWLEDGE.
April, 1913.
Being south of Sun, it is less well placed for Northern
observers than it was as an evening star.
The Moon.— New 6d 8h 24m m ; First Quarter 13d llh45mm :
Full 20d 7h 18mm; Last Quarter 28d 0h 4mw. Perigee
16d 2hra, semi-diameter 16' 15". Apogee 28d 8hw, semi-
diameter 14' 49". Maximum Librations, 7d 5° E, 9d 7° S.,
22'1 5° W., 22li 7° N. The letters indicate the region of
the Moon's limb brought into view by libration. E. VV. are
with reference to our sky, not as they would appear to an
observer on the Moon.
Mars is a morning Star, but not yet well placed for obser-
vation.
Ceres and Pallas are well placed for observation. They
are of magnitude 7 and 8 respectively.
Jupiter is a morning star. Polar semi-diameter, 20".
Table 28.
Day.
West.
East
Day.
West.
East.
Mav. l
4i
O
23
May. 1 7
412 O 3
11 2
42
O
13
,. 18
43 O 12
41
O
3
2%
» 19
431
3
>. 4
43
U
1 2
„ 20
432
D 1
» 5
43>2
O
,, 21
4?
D 2
>, 6
432
0
1
,, 22
4
D 123
„ 7
4'3
u
2
>. 23
42
D" 3 '»"•
,, 8
4
0
23
>. 24
421 O 3
• > 9
2
0
143
.. 25
3
D 412
,, 10
I
0
34
29
,, 26
31
3 4
» ii
3
0
124
„ 27
32
0 14
,, 12
312
0
4
„ 28
3i
D 24
.. 13
32
0
14
„ 29
31324
,, 14
1
0
24
3«
„ 30
21
3 34
» 15
0
1234
>> 31
2
3 34
„ 16
2
0
43
i*
Configurations of Jupiter's satellites at 2h m for an inverting
telescope.
Satellite phenomena visible at Greenwich, ld lh 39m I. Tr. E-,
2h 58m II. Sh. I.; 3d 2h 29m II. Oc. R. ; 7d 0h 36m 43s
III. Ec. R., 2h llm III. Oc. D.; 2h54m46s I. Ec. D. ; 8d lh llm
I. Tr. I., 2h 19m I. Sh. E., 3h 20,n IV. Oc. D., 3h 29m I. Tr. E. ;
9d 0h 47m I. Oc. R.; 14d lh 37m 25s III. Ec. D. ; 15d lh 56m
I. Sh. I., 2h 59m I. Tr. I.; 16d lh 24m IV. Sh. I., 2h 36m
I. Oc. R.. 3h 31ra IV. Sh. E. ; 16d llh 44rae I. Tr. E. ;
17d 2h 27m 58s II. Ec. D. ; 19d 0" 16m II. Sh. E., 2h 19m
II. Tr. E. ; 22d 3h 49m I. Sh. I.; 23d lh 10ra 528 I. Ec. D. ;
23d llh 13me I. Tr. I.; 24d 0h 35m I. Sh. E. lh 31m I. Tr. E. ;
25d 2h 14m III. Tr. E. ; 26d 0h 3m II. Sh. I.. lh 52m II. Tr. I.,
2h 52m II. Sh. E. ; 30m 3h 4m 46s I. Ec. D. ; 31d 0h llm I. Sh.
I., 0h 59m I. Tr. I., 2h 28m I. Sh. E., 3h 17m I. Tr. E. ;
31d nh 16mc IIX Sh J
All the above, except the three marked e, are in the morning
hours.
Saturn is invisible, being in conjunction with the Sun on
the 29th.
Uranus is a morning star, coining into a better position
for observation.
Neptune is an evening star and was stationary on April
4th. Its motion may be traced on the map of small stars
which was given in "Knowledge" for December, 1911,
page 476.
Meteor Showers (from Mr. Denning's List) : —
Radian
.
Date.
s.
R.A.
1
I >ec.
Mar. to May
263°
+
62°
Rather swift.
April to May
103
+
5*
Slow, yellow.
April to Mas-
296
+
O
Swift, streaks.
May 1 to 6
33S
-
2
Aquarids, swift,
streaks.
,. 7
246
+
3
Slow, bright
,, 11 to 18
231
+
27
Slow, small.
,, 30 to Aug.
333
+
28
Swift, streaks.
,, June
280
+
32
Swift.
,, to Julv
252
—
21
Slow, trains.
„ 18 to 31
245
+
29
Swift, white.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which
two hours will overlap with the following one. Thus the
present list includes R.A. 12h to 16h, next month 14h to 18h, and
so on.
Table 29. Non-Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Maximum.
I\ Comae
h. m.
12 0
+ 19 '3
7-310 14
d.
■36l|
June 8.
SU Virginis ...
12 I
+ 12 -9
8 ' 8 to 13
205
Mav 10.
T Virginis
12 10
- 5 "5
8-2 to 13
339 h
May 15.
T Can. Ven. ... • •
12 26
+ 32 -o
8-6 to n-8
2904
Mar. 26.
R Virginis
12 34
+ 7 '5
6'2 to III
:45i
May 4.
RU Virginis ...
12 43
+ 4 '7
7 '6 to 11*8
440
May 26.
U Virginis
12 47
+ 6 -o
7'7 I" 13
206-9
May 29.
RR Urs. Maj.
1.3 23
+ 62 -8
8-6 to 13
229J .
Apr. 3.
R llydiae
■3 25
-22 -8
3'5 t° i°'i
425
Apr. 17.
T Urs. Min
13 33
+ 73 '9
8-8 to 13
321
Mar. 26.
V Urs. Min
13 37
+ 74 •«
7-510 8-7
7i
Mar. 28.
U Urs. Min
14 16
+ 67 -i
7.6 to 12
327
May 29.
S Bootis
14 18
+ 54 '3
7-7 to 13
273
J "iy 9-
R Camelop ...
14 24
+ 84 -2
7.2 to 13
269-5
June 3.
R Bootis
l4 33
+ 27-1
5.9 to 12
223-3
|une 19.
RR Bootis
14 44
+ 39 7
8-o to 13
196-5
May 18.
Y Librae
15 7
- 5 '7
8-o to 11-3
365
June 12.
RS Librae
15 19
— 22 '6
6.6 to 12
217
Mav 20.
RU Librae ...
1 t 28
-15 "°
8 -4 to 11
314
June 24.
X Coronae
15 46
+ ?6 s
8-4 t.. 13
246
Mav 13.
R Serpentis
'5 47
+ 15 '4
5'6to 13
357
May 16.
RR Librae
15 51
-18 -o
S.2 to 12-6
276.7
June 22.
Z Coronae
15 53
+ 29 '5
8-9 lo 14
245
May 20.
T Coronae
•5 5"
+ 26 '2
Now 9-5
Nova Coronae.
JOHN GRAY, B.Sc.
By G. UDNY YULE.
Readers of " Knowledge " will have heard with
regret that Mr. John Gray, the inventor of the
curious and interesting machine for estimating
mental characteristics, described in "Knowledge"
of December, 1910, passed away at the end of April,
1912, as the result of an attack of pneumonia, and a
a few details with regard to his career will prove
acceptable.
Gray was born in 1854,
at Strichen, Aberdeenshire,
and was educated as an
engineer at the University
of Edinburgh and the Royal
School of Mines, London ;
he obtained the Associate-
ship of the School in Metal-
lurgy in 1878, and the de-
gree of B.Sc. (Engineering)
at Edinburgh in the follow-
ing year. In 1878 he en-
tered the Patent Office, and
at the time of his death
held the position of Exam-
iner, specialising largely in
patents relating to electrical
inventions. During the
earlier part of his life, Gray's
interests lay almost wholly
in matters relating to phy-
sics and electrical engineer-
ing. He was a fellow of
the Physical Society from
1879 to' 1905, and an Asso-
ciate of the Institution of
Electrical Engineers from
Figure 139. The late John Gray, B.Sc.
1887 to 1902. For some
twenty years, even to the year before his death, he
was a regular and valued contributor to The Electrical
Review. To many students of physics his book on
electrical influence machines, which was published
in 1890, and reached a second edition in 190.3, will
be well known.
His first contribution to anthropology was a paper
on the history of the place of his birth, published in
The Transactions of the Biichan Field Club for 189.3.
This was followed by several other contributions to
the Transactions of the Club, and, with the co-
operation of members of the Club, an anthropometric
survey of some fourteen thousand school children
was carried out on a scheme devised by Gray, the
results of which were published in its Transactions
in a joint review by Gray and Tocher in The Journal
of the Anthropological Institute (1900). These Aber-
deenshire surveys paved the way for the survey of
the whole of the school children of Scotland. A
committee was formed consisting of Sir Wm. Turner,
Professor Reid, Mr. Gray and Mr. Tocher, financial
assistance obtained from the Royal Society Govern-
ment Grant Committee, and the survey organised
and very successfully carried out by Mr. Gray and
Mr. Tocher. Grav's memoir on the results was
published in The Journal of the Anthropological
Institute for 1907. Mr.
Gray acted as Secretary of
the Anthropometric Com-
mittee of the British Asso-
ciation (1902-8), and in
1903, in conjunction with
Professor D.J. Cunningham,
he submitted to the Inter-
departmental Committee on
Physical Deterioration a
scheme for an anthropo-
metric committee of the
British Isles.
Gray possessed very
marked mechanical abili-
ties, and devised a number
of new instruments or new
forms of instrument for
anthropometric work, e.g.,
a portable stature meter,
callipers, a radiometer, a
perigraph or instrument
for drawing contours of
skulls or bones, and an
adaptation
tintometer
the colour
eyes. During the last few
years he had been specially interested in the machine
referred to at the commencement of this notice. In
its first form this instrument measured the speed at
which the observer ceased to see flicker in a revolving
disc coloured in black and white segments, the disc
being replaced in the later and improved form
(" Knowledge" loc. cit.) by a revolving mirror
reflecting alternately white and coloured light. The
actual speed was very nearly constant for the same
observer, but varied greatly for different persons, and
seemed to exhibit remarkable relations to the mental
characteristics. He was still at work on this machine
at the time of his death.
That Gray possessed not only scientific abilities
and skill in mechanical invention, but also great
capacity for organisation, will have been evident
from his work on the anthropometric surveys. This
capacity he placed at the service of the Anthropo-
of Lovibond's
for analysing
of hair, skin or
141
142
KNOWLEDGE.
Apri
1913.
logical Institute, when, in 1904, he accepted the
Treasurership and by untiring effort succeeded in
placing the finances on a sound basis. He also
acted as Treasurer of the Universal Races Congress
of 1911, and at the time of his death was serving as
Assistant Treasurer of the Congress of Americanists.
In 1909 he was elected a foreign associate of the
Anthropological Society of Paris.
A NEW GRATING SPECTROGRAPH.
By A. H. STUART, B.Sc, F.R.A.S.
Those of us who have read how Fraunhofer made diffraction
gratings by winding silver wire of diameter -041111X1. on brass
frames and then, with them, measured the wavelengths of lines
in the solar spectrum with a surprising degree of accuracy, have
envied little except his patience. We have only envied others
their apparatus when we have read of the wonderful reflec-
tion gratings made by Rowland, and the huge map of the
sun's spectrum which he obtained by their aid. This map set
the pace, so to speak, in this class of work, and is still of con-
siderable value as a standard, in spite of the classical work
which Michelson has done with his interferometer. It is the
dealers' catalogues that are responsible for stifling our
enthusiasm for work with reflection gratings, for even a small
instrument of this type costs from £\0 to £20. By the
judicious expenditure of £l, however, I have been able to
construct a spectrograph on this principle.
Figure 140 shews this instrument in diagram. S is the slit of
the instrument, L is an achromatic lens (2-ins. diameter
and 30-in. focal length, value 3s. 6d). Immediately behind
L is placed a transmission grating (a moulded replica on
glass, value 10s. 6d.,
gives good results),
with the prepared
surface as close to
the lens as possible.
Behind this again, is
placed a plane mirror
M. C is a camera-
back upon which
the spectrum produced
is focused. The dis-
tance from L to S and
L to C should be
equal to the focal
length of the lens L.
The whole is con-
tained in a light-tight
wooden box, PORS
in figure.
Now in order to get
the various parts of the
instrument correctly
fixed, it is necessary
to consider in detail
what happens to a
pencil of light when it
falls on to the grating.
For our purpose we
may neglect all except
the spectra of the first
order, and it will be
convenient to consider
the rays which have
suffered the least
deviation (with a grat-
ing the violet end of
the spectrum is devi-
lens all rays in the
Now in
"W
Figure 140.
9'
;b
>»
ated the least). If we use a glass
ultra-violet beyond \ = 3600 will be absorbed.
Figure 141 the light travels down from S and falls on the
grating G normally. A large portion of this light passes
through the grating unchanged, and falls on the mirror M at
A. If it meet the mirror normally it will be reflected back to
the grating and a spectrum will pass out towards C. This is
the spectrum which is to reach the camera. Other spectra
are, however, formed, and these must be avoided. Those
which are deviated to the right
may be neglected, since they ci
are absorbed by the side of the
containing box (which should
be blackened). When the
light first falls on the grating
a spectrum will be deviated to
the left and will be reflected by
the mirror towards B. The
mirror must be so placed that
this spectrum does not fall on
the lens. Using a grating
having 14,438 lines to the inch,
the angle 8 for X = 3600 is
about 14° 39', and in order
that the ray B may just miss
a lens 2 inches in diameter,
the mirror must be placed
3-9 inches behind the lens.
There is yet another spectrum
to be considered. The light
falling on the grating in the
first case will form a faint
reflection spectrum which will,
under the present conditions,
be more or less superimposed
on the spectrum we want to
photograph. To avoid this I
have found it convenient to
retain the grating at right
angles to the incident
light, but to have the mirror slightly twisted, as shewn
in Figure 140. This will separate the spectrum we want
from the faint one caused by reflection from the grating
surface.
We thus have in the camera a pure spectrum of considerable
dispersion at a very trifling instrumental cost and the sacrifice
of a little light.
It is wise to hang a black screen across the box, so that the
lens just protrudes; this will absorb any stray reflections from
the mirror.
By having a piece of wood just large enough to fit into the
rebates of the camera back, and mounting in the middle of it
an ordinary telescope eyepiece, the instrument may be used
as a spectroscope. I have found it convenient to mount the
mirror (M in Figure 140) on a turntable, and to have a long
lever attachment (very much geared down) regulated from
near the eyepiece. By this means a steady movement of the
mirror will cause the whole of the visible spectrum to move
slowly across the field of view.
'i»;
A
m
Figure 141.
SOLAR DISTURBANCES DURING FEBRUARY, 1913.
BY FRANK C. DENNETT.
February has yielded a much better proportion of observing
days than did the previous month. On only two — 3rd and
12th — was the sun quite missed, but of the remaining days
the disc appeared quite free from disturbance on no less than
fifteen, as none was seen until the 18th. The central meridan
at noon on February 1st, was 318° 0'.
No. 4. — On the 18th a bright faculic cloud was noted round
the north-eastern limb, which on the evening of the 19th was
found to contain pores. On the 20th there were three spotlets
and some minute pores, but next day the leader was some
9,000 miles in diameter, and the group about 45,000 miles in
length. On the 22nd and 23rd a trail of three or four pores
stretched back from the southern side of the leader, and a
somewhat lesser trail reached forward from the back spotlet,
the group now extending over 82,000 miles. From the 24th
to the 26th, only the leader was visible with a small pore
closely south-east, the latter being gone on the 27th. On the
28th only the faculae remained visible in place of the group.
The high northern latitude of this disturbance quite marks it
as belonging to the new cycle.
Although only one disturbance has been recorded during
the month, and that showing but little activity from a spectro-
scopic point of view, except upon the 21st and 22nd, when
the C. line showed much deflection, and at one time an
eruptive flocculus, it is probable that during the present
year there will be a gradual but marked increase of
disturbance.
The observers have been Messrs. John McHarg, C. J.
Simpson, D. Booth, W. H. Izzard, C. Frooms, E. F. Peacock,
and the writer.
DAY OF FEBRUARY.
25
?
23
V
V
20
19
t
17
&
II
H
13.
a.
ii
10.
a
s
7
S
s.
4
5
>.
1.
26
7
!(x
s
y
20
'0
0
K
zo
30
N
Q
j
20
.-—
j
<►
i
f t 0
N
0 I ZO X 40 50 60 70 80 SO 100 110 120 130 140 150 160 170 180 190 ?00 210 220 230 240 250 260 270 280 290 300 310 320 330 340 350 360
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.K.A.S.
STELLAR PARALLAX. — An important programme in
this field has been carried out at the Observatory of Yale
University by Messrs. F. L. Chase and M. F. Smith. An
interesting summary of the results is given in Popular
Astronomy for Februarv, which we reproduce below in
Table 30 :—
on account of sensible proper motion. The following large
parallaxes were found : —
Par.
e Eridani "-31
S Eridani ... ... ... -18
W.B. XVI 906 -21
The last is a faint star of magnitude 8-8, the proper motion
being l"-29. e Eridani appears to be one of the Sun's twelve
nearest neighbours.
Table 30.
Proper Motion.
"00 to "34.
"•41 to
"•54.
"■55 to
"■65.
"•66 to
"•96.
"■97 to
7"-04.
Mean.
Magnitude.
™ean No.
Par.
Mean
Par.
No.
Mean
Par.
No.
Mean
Par.
No.
Mean
Par.
No.
Mean v,
Par. No-
0 to 3
"•02 18
"■10
2
"■11
3
it
"•20
2
"•06 25
3 „ 5
•03 9
•02
7
■11
5
•10
10
•18
7
•08 38
5 „ 7
-•01 7
■04
17
•06
19
•04
18
•09
15
•05 76
7 „ 9
•04
31
•03
26
•02
27
•12
15
•04 99
Means
•01 34
•04
57
•05
53
•04
55
•12
39
—
As might be expected, the parallax increases with the proper
motion. The dependence on brightness is less marked, but it is
to be remembered that while the list is fairly exhaustive for
the brighter stars, it only contains selected faint ones, chosen
SUN SPOTS. — Mr. Maunder contributes an interesting
article on Sunspots to the January number of Scientia. He
first points out the abruptness of the transition from spot-
activity to quiescence, which is frequently accomplished in a
143
144
KNOWLEDGE.
April, 1913.
single year. He then passes to consider Spoerer's law of
fluctuation of spot zones. At the beginning of a cycle, spots
break out in high north and south latitudes, and as the cycle
progresses they gradually close in on the equator. There is
an overlap of a year or two between one cycle and the next,
equatorial spots belonging to the expiring cycle appearing
concurrently with the high-latitude spots of the new one. We
are now in this period of overlap, spots of the new cycle having
begun to appear in December, and one in latitude 37° North
having crossed the central meridian on February 23rd. Mr.
Maunder considers that this fluctuation in latitude indicates
that the spot-cycle is not due to external bodies such as
planets, comets, or meteor swarms, but is due to some change
within the Sun itself.
He further holds that since the variation in latitude
synchronises with the eleven year cycle of activity, and with
no other cycle, this is the only genuine cycle of sunspot
change. Professor Schuster announced cycles of 4-79 years
and 8-36 years from his " Periodogram " treatment of the
numbers expressing the daily spotted area. But these periods
do not fit in with the latitude shift of the spots, and Mr.
Maunder denies their reality as genuine solar cycles. He
suggests that the periodogram has indicated them since they
may be times " in which the average life of a normal group of
spots becomes commensurate with half the synodic rotation
period of the Sun."
POSSIBLE SHORT PERIOD VARIATIONS IN THE
SOLAR RADIATION.— The Mount Wilson observations
having suggested that there were real variations in the Sun's
radiation, it was decided that Messrs. Abbot and Angstrom
should make observations in Algeria, while Mr. Aldrich
observed on Mount Wilson. It was very improbable that
any influence that was merely terrestrial would simultaneously
affect these distant stations in the same manner. The results
of 1911 are considered to make the variation of the Sun to an
extent of ten per cent, in a period of a few days highly
probable.
The weather conditions in 1912 were more favourable, and
it is hoped that the observations made then will suffice to
settle the question.
The a priori probabilities are considerably against so large
a variation in so short a period. But it must be admitted
that if the observations in Africa and California systematically
agree, they would go far to establish its reality.
MEASURES OF THE PLANETS.— The fourth volume
of The Annals of Strassburg Observatory contains a series
of measures of the dimensions of the planets. —
In angle at
distance unity. In miles.
Mercury 6"-431 2,893
Venus 16 -782 7,552
Mars 9 -674 4,352
Jupiter, Equat. ... 199-04 89,553
Polar ... 187 -23 84,242
Saturn, Equat. ... 171 -65 77,232
Polar ... 153 -44 69,038
Diam. of Ring 382 -70 172,191
Uranus 67 -90 30.550
Neptune 69 -30 31,180
H. Samter has deduced the mass of Titan from its perturbing
effect on Hyperion. Two different methods gave 1/4125 and
1/3910, Saturn being taken as unity. The accordance is good.
In giving diameters in miles, Hinks' value of the Sun's
Parallax, 8" -807, has been used.
The compression of Jupiter is given as
Saturn
16-87
1
" 9-426
It is curious how difficult it is to decide which of the two
outermost planets is the larger. The earlier measures gave
Neptune, most recent ones give Uranus, while the present
series is again in favour of Neptune. The diameter of Mars
is almost exactly twice that of the Moon.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
WEEDS OF ARABLE LAND.— Miss Winifred Brenchley
(Annals of Botany, 1911, 1912, 1913) has published three
papers dealing respectively with investigations carried out in
(1) Bedfordshire on soils derived from the Chalk, Gault,
Lower Greensand, and Oxford Clay; (2) parts of Somerset
and Wiltshire, the Upper Greensand, Chalk, and Clay (Fuller's
Earth) coming under consideration; and (3) Norfolk, on a
variety of soils, including gravel, sand, loam, and clay,
forming the drift deposits known as North Sea Drift and
Boulder Clay, in addition to the outcrops in West Norfolk
of the Chalk, Gault and Lower Greensand. The author's
object was to determine the relations existing between the
weeds, soils, and crops of arable land. The more important
weeds are classified with their habits and relative dominance,
and details are given as to the weeds of clay, chalk, sandy, and
other soils. In the second paper, special mention is made of
the " calcifuge " species.
It is shown that in each district investigated a definite
relation exists between the weeds of arable land and the soils
on which they grow. This relation may be local, when a
weed is symptomatic of a certain soil in one district but is not
so exclusively associated with it in another ; or general, when
a certain species is symptomatic or characteristic of the same
type of soil in different districts. The determining factor of
the association is the actual texture of the soil, and not so
much the geological formation from which it is derived,
except with soils overlying chalk. The crop has very little
influence on the weeds occurring except in the case of seed
crops, which probably smother out species which would
normally occur. The weeds found in seed crops seem to be
constant, and certain other plants show the same association
with particular types of crop in various districts. The relative
prevalence of the weeds varies somewhat in the different
districts, certain species which are more or less common in
one place being practically absent in another, on similar soils.
Naturally, the general relations will need more exhaustive
proof than the local relations, and a true estimate will only be
obtained as the field of investigation is enlarged, since each
fresh observation ratifies or discounts the previous deductions.
In the first two papers, dealing with Bedfordshire, Somerset-
shire and Wiltshire, special care was taken to select districts
without drift deposits, so that the soils might be regarded in the
main as derived from the geological formations immediately
underlying them,e.£., Greensand, Chalk, Gault. The conclusion
that the geological derivation has little to do with determining
the weed flora, and that the texture of the soil is a far more im-
portant factor, was fully verified by the results of the investiga-
tions made in Norfolk on drift soils. In one district a curious
mingling of " acid " and " chalk " plants was found, possibly
owing to the super-position' of a thin layer of non-calcareous
sand on a chalk subsoil, the difference in the root-systems of
the plants enabling each to tap the particular soil most suited
to its needs.
WIND AND TREE-GROWTH.— Even the most casual
observer, who has been at the sea-coast or on mountain
heights, must have noticed that full exposure to strong winds
coming from one direction has a marked influence on the
appearance of trees. In such exposed situations the entire
tree may lean with the prevailing wind, or the trunk may grow
erect while all the branches are on the leeward side, the
branches which come out on the windward side being appar-
ently bent round in the opposite direction by the force of the
wind, and kept bent in this way so continuously that the
growth and hardening of the wood has finally fixed the branch
in this position. At any rate, this appears to be the simplest
explanation, and a good example of the power of habit — the
young branch finds it easier to bend with the wind than to
resist it, and when it becomes old this habit is fixed and the
bent and gnarled branches could not then straighten even if
the wind abated. Hence, it has usually been supposed that
the permanent bending of trees and of their branches in the
direction of the wind is due to the mechanical action of the
April. 1913.
KNOWLEDGE
145
wind, and also to the pruning action of sharp salt or cold
winds, which shrivel up the buds on the windward side as soon
as they appear on the tree — this would account for the absence
of branches on this side of the tree, which is often observed.
However, Jaccard (Journ. forest. Suisse, 1912) has called
this explanation in question, and has put forward a very
different one. He takes into account not only the general
form of the tree, but also the effect of growth in exposed
places upon the thickening of the trunk ; emphasizes the
fact that there is a close relationship between growth of
the leafy crown, the activity of the cambium or growing layer
between wood and bark, and the extension of the root system
in the soil ; and points out that variations in the rate of water
transport up the stem play an important part in the progress
and localisation of growth in thickness of the wood. He gives
the results of extensive comparisons of sections of the wood,
showing the anatomical correlation between roots, trunk, and
branches, in support of his contention that the modifications
in direction of growth, and in the secondary thickening of the
woody trunk and twigs, are due to various factors concerned
in the nutrition of the plant rather than to the mere mechanical
action of the wind, which he does not consider affords a com-
plete explanation of this familiar phenomenon.
Jaccard's observations and interpretations are of great
interest, but further work on the subject appears to be
required before one can feel convinced that his main
conclusion is correct ; for it is somewhat difficult to see how
the characteristic T-shaped form of trees exposed to strong
winds can be fully explained without reference to the
mechanical action of the prevailing wind.
THE GRAFT-HYBRID CYTISUS ADAML— The
remarkable experiments of Winkler and Baur on the pro-
duction of " graft-hybrids " and " chimaeras " were described
in these columns some time ago ("KNOWLEDGE," 1911,
page 186). At the meeting of the Royal Society on June 20th,
1912, Professor Keeble and Dr. E. F. Armstrong read a paper
on '■ The Oxydases of Cytisus Adami." The investigation
described in this paper was undertaken with a two-fold
object: (1) to test Baur's hypothesis that this graft-hybrid is
a periclinal chimaera composed of an epidermis derived from
Cytisus purpureus and a body derived from Cytisus
Laburnum, and (2) to ascertain whether migration of
oxydases (oxidising ferments) may occur in plants. The
results confirmed Baur's conclusions, and indicated that
oxydases may pass from one tissue to another. Tests
applied to the flowers of the three forms showed that
C. Adami and C. purpureus contain a direct epidermal
oxydase and that C. Laburnum does not; also that a direct
oxydase is contained in the veins of C. purpureus, while the
veins of C. Adami and C. Laburnum contain peroxydase and
not a direct oxydase. In other words, C. Adami is identical
with C. purpureus with respect to its epidermal oxydase, and
with C. Laburnum with respect to its bundle (vein) oxydase.
The evidence pointing to oxydase migration is as follows : The
buff standards of C. Adami, like the yellow standards C. Labur-
num are marked by lines of chocolate colour, due to anthocyan
pigment contained in sub-epidermal cells. Sections across
these pigmented areas of C. Adami show that they coincide
with deeply pigmented epidermal cells. Over the other parts
of the standard the pigmentation of the epidermis is faint ;
over the sub-epidermal pigmented areas it is well-marked.
Inasmuch as the fainter pigmentation is due to inhibition of
pigment-formation it is concluded that the deeper pigment-
ation is to be attributed to the passage of oxydase from sub-
epidermal pigmented cells to contiguous epidermal cells.
The failure of the buff flowers of C. Adami to develop their
purple pigment as fully as that pigment is developed in the
purple flowers becomes intelligible on the hypothesis of
oxydase-migration ; for, whereas the purple-flowered branches
contain a bundle oxydase which may reinforce that of the
epidermis in affecting pigment-formation, the vascular tissues
of C. Adami contain no direct oxydase and hence cannot aid
the epidermal cells in their work of pigment-production.
In connection with this interesting " chimaera," mention may
be made of a paper by Janssonius and Moll (Rcc. trav. hot.
Neerlandais, 1911, page. 333-368) on the minute structure of
the wood of Cytisus Adami and its components. These
writers find that, as might be expected, the wood of this form
closely resembles that of the laburnum and differs from that of
C. purpureus. The wood of C. Adami cannot be said to be
on the whole intermediate in structure between that of the
two " parents," but shows certain peculiarities which may be
due to the influence of C. purpureus.
Buder (Ber. deutsch. bot. Ges., Band 28 ; Zeit. f. indukt.
Abst.-u. Verereb.-Lehre, Band 5) has made a very thorough
study of the minute structure of Cytisus Adami, and has
added various details to the descriptions of previous writers.
He also confirms the view, established by the work of
Macfarlane, Baur, and Winkler, that this form is a periclinal
chimaera. He finds that the protoplasm of the epidermal
cells is joined to that in the cells below by fine threads passing
through the cell-walls, just as is the case with the various
cells making up the living tissues of plants in general. The
nuclei of C. Laburnum are smaller than those of C. purpureus ;
those of the epidermis in C. Adami are of the purpureus
size, those of the underlying cells are of the Laburnum size.
In C. purpureus nearly all the cells contain tannin ; in
C. Adami it is present only in the epidermis. In C. purpureus
the cork-producing cambium arises in the sub-epidermal layer,
in C. Laburnum in the epidermis itself; in C. Adami the
cork may be formed from the hypodermis, or from the epidermis
or from both layers — all three cases may be seen in the same
twig. In such details as effect the epidermal layer of cells
(form of hairs, cuticle, stomata, and so on), C. Adami agrees
exactly with C. purpureus. A curious detail is the fact that
in C. Adami the nucellus of the ovule projects beyond the
micropyle ; this is easily explained as owing to the rapid
growth of the inner (Laburnum) tissue of the ovule as
compared with the outer (purpureus) integument.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon), F.I.C.
. HYDRIDES OF BORON.— Many attempts have been
made to prepare definite hydrides of boron, but the instability
of these compounds has hitherto prevented their isolation in
a pure state. These difficulties have been overcome by
Messrs. Stock and Massenez (Ber. d. deut. Chem. Ges., 1912,
XLV, 3539), who have succeeded in preparing definite com-
pounds of hydrogen and boron by causing magnesium boride
to fall little by little into slightly heated dilute hydrochloric
acid. The gases evolved in the reaction were condensed in a
series of tubes chilled by means of liquid air, and the condensed
portions were then fractionated by replacing the liquid air,
first by a mixture of acetone and solid carbon dioxide ( — 82°C.
to -75DC), then by liquid ammonia ( — 45°C. to — 35°C), and
finally by ice.
By these means two hydrides of boron were isolated, with
compositions corresponding to the formulae B4 Hioand B(i Hi*.
The first of these melted at about — 112°C, and easily decom-
posed into a series of other boron hydrides. In the gaseous
form it ignited spontaneously in the presence of air or oxygen,
and produced dangerous explosions in vessels with narrow
openings.
The other hydride, B« H12, was a colourless liquid, which
had a repulsive odour, and, like its companion, took fire
spontaneously on contact with air. At the ordinary pressure
it boiled at about 100°C. It was readily decomposed by water,
and, when treated with alkali solutions, yielded hydrogen. A
trace of this hydride left in a vessel may give rise to a dangerous
explosion on admission of air, and it is recommended as a
precaution that the flasks should be rinsed with a solution of
sodium hydroxide before allowing any air to enter.
THE BIRTH OF AN ATOM.— Two papers were recently
read before the Chemical Society, the importance of which to
physics and chemistry it is hardly possible to over-estimate.
At the time of writing, the official account has not been pub-
lished, but an excellent outline, taken from a report to The
146
KNOWLEDGE.
April. 1913.
Morning Post, will be found in The Chemical News, 1913,
CVII, 78.
As has happened on several previous occasions in science,
the same discovery has been independently made by more
than one worker, approaching the subject from different points
of view.
The first of these papers, " On the Presence of Helium in
the Gases from the Interior of X-ray Tubes," was read by
Sir William Ramsay, and was the outcome of his attempts to
obtain evidence of chemical transformations effected through
the agency of the p-rays given off in the decomposition of
radium emanation. With this idea several old X-ray tubes
were examined, and in each case helium, neon and argon were
found in the gases within them. Possibly this helium was
produced by the impact of the rays upon the glass walls of the
tubes. As to the neon, its origin was suggested by the fact
that on decomposing water by means of radium emanation,
neon is produced in proportions indicated by the equation : —
Helium + Oxygen = Neon.
4 16 20
These experiments of Sir William Ramsay were supple-
mented by the second paper on "The Presence of Neon in
Hydrogen after passage of an Electric Discharge through
Hydrogen at Low Pressures," which embodied results
independently obtained by Professor Collie and Mr. H.
Patterson.
In this paper it was shown that when an electric discharge
was passed through a vacuum tube containing hydrogen,
helium and neon (which could be identified by their spectra),
were invariably produced.
All precautions were taken to exclude the possibility of the
introduction of any helium during the experiments, so that
the conclusion was justified that there were only two
explanations of the phenomenon : — (1) That the hydrogen
or elements in the glass or electrodes had been transmuted
into helium and neon ; or (2) That the energy of the
discharge had created helium and neon from the immaterial
ether.
Mr. Patterson suggested that a possible hypothesis from
the purely physical standpoint was that by doubling the
electric charge upon the atom of hydrogen it might con-
ceivably be converted into a-particles and so into helium.
When the experiments were repeated, with the tube con-
taining hydrogen surrounded by an outer vacuum tube, helium
was found in the latter, apparently owing to its diffusion
through the glass of the inner tube. On then introducing
pure oxygen into the outer tube, neon was obtained, the
equation suggesting the same proportions as observed by
Sir William Ramsay: —
Helium + Oxygen = Neon.
4 16 20
Hence the conclusion was drawn that if the helium produced
in the inner tube had sufficient velocity to diffuse into the
outer tube, it was quite possible for a new element, neon, to be
formed.
It is now accepted as a proved fact that the element radium
decomposes with the formation of other elements, the simplest
of which is apparently helium, and the experiments of Sir
William Ramsay have indicated that the energy liberated by
radium can effect the transmutation of other elements into
one another ; but in such cases man can only watch the
changes that go on, and cannot control or vary them. But in
the building-up process that has apparently now been dis-
covered, the energy for the change is artificially supplied and
controlled, and the changes are thus of a different order from
the radioactive decompositions of a decaying element.
To quote the words of Professor Collie — " We are possibly
dealing with the primordial form of matter, the primordial atom,
which when produced had all the energy necessary for form-
ing the world. By combination of these ' atoms ' the atoms
of elements could be formed. Possibly the electric current
directed the flow of these atoms with the full force of its
energy, and with the phenomena of heat and light the
elements came into existence,"
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
RECENT AMERICAN MEMOIRS.— Geologists in the
United States are fortunate in having a large number of
periodicals and transactions in which to publish their work ;
and, judging from the elaborate and expensively-illustrated
memoirs which are constantly being turned out, these
societies must have plenty of money to spend. The United
States Geological Survey also publishes on a lavish scale.
Some recently-issued memoirs are noticed below.
A "Bibliography of the Geology and Mineralogy of Tin,"
by F. L. Hess and Eva Hess (Smithsonian Miscellaneous
Collections, Vol. LVIII, No. 2) is a very elaborate and
exhaustive work, containing one thousand seven hundred
and one entries. These are principally listed under countries,
but subordinate headings are General Bibliography, Mining
and Milling, History, Metallurgy, Chemistry, Mineralogy and
Statistics. Of the more important papers useful digests have
been prepared. An index covering one hundred and sixty-
nine pages completes the usefulness of this work.
" The Early Palaeozoic Bryozoa of the Baltic Provinces,"
by R. S. Bassler (United States National Museum, Bulletin
77) is a memoir of three hundred and eighty-two pages,
with thirteen plates and two hundred and twenty-six text-
figures. The fossils of the Russian Baltic area, found in
almost unconsolidated Lower Palaeozoic strata, are renowned
all over the world for their abundance and exquisite state of
preservation. This work is as complete a study of the Russian
Ordovician Bryozoa as the available collections would allow.
A single Cambrian form, the oldest known Bryozoan, is
described. A digest of the Lower Palaeozoic geology of
Baltic Russia is given, and the Russian beds are correlated
with their stratigraphical equivalents in North America.
For stratigraphers a work of inestimable value is that just
issued by the United States Geological Survey under the title
" Index to the Stratigraphy of North America" (Professional
Paper No. 71). This important publication has been compiled
by Bailey Willis and G. W. Stose, and runs to eight hundred
and ninety-four pages. The aim is to summarize North
American stratigraphy as fully as the data available and the
scope of the work permit. The material includes some
discussion of stratigraphy, some citations of fossils, and views
on correlation. The work is accompanied by a geological
map of North America in four sheets, making a wall-map
60 X 77 inches, whereon the geology is set out in forty-two
colours. In addition the text contains eighteen sketch maps,
giving the areal distribution of the combined formations of
each system. This is a magnificent piece of work, for which
geologists all over the world will be grateful.
Palaeontologists, likewise, will be grateful to the United
States Geological Survey for the publication of Dr. Walcott's
monumental monograph on the Cambrian Brachiopoda of the
world. This is the crowning achievement of Dr. Walcott's
lifelong work on Cambrian rocks and fossils, on which he is
the foremost authority. Five hundred and thirty-six species
and varieties, grouped in forty-four genera and fifteen sub-
genera, are described, along with forty-three Ordovician forms.
The great bulk of Cambrian brachiopods are inarticulate,
phosphatic-shelled forms, and they attained their maximum of
specific differentiation in the Middle Cambrian, where there
are thirty-one genera and three hundred and fifty-five species.
Even in the Lower Cambrian there are thirty-two genera and
one hundred and sixteen species, showing that the Brachiopoda
must have originated much farther back in time than the
earliest fossiliferous rocks. Dr. Walcott concludes that each
species is, in general, confined to one type of sediment, and out
of five hundred forms only one hundred and fifty have been
found in more than one kind of sediment. The " facies " of
the rock, therefore, becomes very important in palaeontology,
and especially in zonal stratigraphy.
A RIEBECKITE ROCK FROM ARRAN— Igneous rocks
containing the rare soda-amphibole riebeckite are now known
to occur in several British localities. The best known is that
April, 1913.
KNOWLEDGE.
147
of Ailsa Craig, the " ocean pyramid " rising in the middle of
the Firth of Clyde, but other types occur at Mynydd Mawr
in Wales, in the island of Skye, and in the Lower Carboni-
ferous eruptives of the Kildon Hills, near Melrose. A further
example, recently discovered by the writer, is important, since
it occurs with much the same geological relations, and only a
few miles from Ailsa Craig. The rock referred to forms the
great so-called " felsite " boss of the Holy Isle, near Lamlash,
Arran. This intrusion rises from the sea to over a thousand
feet in a steep pyramidal hill, strikingly similar to Ailsa
Craig. The rock weathers deeply to a soft, crumbling,
yellowish " felsite " ; but on breaking a large block, the
interior is found to be composed of a fresh dark-grey rock,
which, on sectioning, proves to contain
riebeckite. The rest of the rock is built
mainly of short stumpy prisms of sanidine,
with a few irregular interstitial grains
of quartz. The riebeckite forms typical
spongy masses, with a characteristic ^A
pleochroism from indigo-blue to yellowish- flP
green. The rock is a riebeckite-
orthophyre, and differs from that of Ailsa '
Craig only in its comparative freedom
from quartz.
MICROSCOPY.
By F.R.M.S.
QUEKETT MICROSCOPICAL FlGUR
CLUB.— February 25th, 47th annual
general meeting. The presidential address
on "The By-Products of Organic Involu-
tion," was given by Professor A. Dendy,
F.R.S. After referring to well-known
cases of by-products in industry, the
President thought that nowhere in the
animal kingdom is there a more exact
analogy than in the familiar rotifer
Melicerta which builds for itself a
dwelling-place out of its own waste-
products. The main part of the address
was devoted to a consideration of the
evolution of the very many forms of sponge
spicules from the primitive ancestral form
consisting, in the case of the Tetraxonida,
of four rays diverging at equal angles
from a common centre. The development
of the orthotriaene, dichotriaene, pro-
triaene, anatriaene, and discotriaene forms Figur
was then traced. An altogether different
line of evolution from the primitive tetract
archetype appears to have given rise to the typical oxeote
spicules of the monaxonellid division of the Tetraxonida. In
the course of evolution the distinction between skeleton
spicules (megascleres) and flesh spicules (microscleres)
becomes very marked. Both had, doubtless, a common
origin, but whereas the megascleres are obviously adapted as
the principal skeletal elements and are arranged accordingly
in the sponge, the microscleres are scattered at random
through the soft ground substance and in the majority of
cases it is impossible to assign any value at all to their
presence. They are, however, so constant and characteristic
that they afford by far the most convenient and reliable data
for the classification of the tetraxonid sponges. The President
had previously suggested that the various forms were
determined by differences in the hereditary constitution of the
mother-cell, and in our ignorance we may assume that such
differences arise spontaneously in the germ-plasm, and that it
is a mere chance whether or not they may prove to be of any
value to the organism. Or, again, the differences may be due
to the permutations and combinations of ancestral characters
which take place in the maturation and fertilisation of the
germ-cells, or to the influence of some change of environment
upon the germ-plasm. If the characters of sponge-spicules
are really of the nature of mutations it should be possible in
the future to obtain Mendelian results by hybridisation, but
we should require to know a great deal more than we do now
about the breeding habits and life-history of sponges before
we could hope to bring such experiments to a successful
issue.
A USEFUL POCKET CASE FOR MICRO-SLIDES —
The microscopist often wants to carry in his pocket a dozen
or so slides. It is true that small boxes for holding a dozen
or a score of slides are on the market. But one may not be
able to obtain these at short notice. Again, it is a convenience
to have several of these boxes and those with a limited pocket
may be glad to spend a hour or two's time rather than so
many shillings.
The two contrivances hereinafter des-
cribed merely require some pieces of card
or straw board, a fairly sharp knife, some
fish glue or strong gum solution, and a
little patience, for their making, which is a
very simple matter.
If the reader is not a photographer he is
pretty sure to have the acquaintance of
one, from whom he can, for the asking,
obtain an empty quarter-plate card-box
with lid, and very probably also some
fairly stout pieces of yellow straw board,
such as is often sent out as packing along
with packets of bromide and similar
E 142. printing papers. The quarter-plate meas-
ures four and a quarter by three and a
quarter inches, and the boxes are about
four and a half by three and a half inches
inside, and one inch or so deep.
In Figure 142 we see such a box fitted
to carry three-inch micro-slips. First
we cut a number of cards one inch long
and one-tenth to one-eighth of an inch
wide. Next cut two strips one inch wide
and four and a half inches in length, i.e.,
just to fit the inside of the longer side of
the box. The short bits are fixed to the
two longer pieces with an interspace just
large enough to take the thickness of a
glass slip easily. This, I find, provides for
sixteen slips in a quarter-plate box. As
the box is three and a half inches wide,
and the slips only three inches long, we
have to pack up with extra strips of card
e 143. four and a half inches by one inch behind
each side piece. In my case two pieces of
packing behind each stepped piece gave an
easy fit. A glance at Figure 142 will make all clear. The
triangular object behind the open box containing one mount
and one clear glass is the box lid on which the box is resting
to tilt it up for the purpose of being photographed.
We microscopists frequently want to lay aside a number of
freshly-made mounts in a horizontal position to set, or dry.
If such a box be set up to rest on its smaller end, we have
such a contrivance. Half-a-dozen of these drying boxes (i.e.,
containing ninety- six slips), tied back to back in pairs with a bit
of thread, take up very little room, and can be left on the top
shelf of a book-case, thus drying off slides in a few hours.
The second contrivance is, perhaps, a little more trouble to
make, but has the advantage of holding the mounts horizontal
when the box is laid flat on the table in the usual way. Here,
again, we utilise a quarter-plate box. The complete article is
shown in Figure 143 ; the box, is shown containing four card
trays, each tray carrying four mounts (Figure 144). A semi-
circular piece of card is cut away from the centre of one side
of the box (Figure 143), to enable one to lift out the trays.
To the inside of the lid are fixed by fish-glue two folded-up
strips of thick cloth. These form a kind of soft spring pad,
which keeps the contents of the box from shifting about when
the box is being carried about in the pocket.
A glance at Figure 144 shows that either of the two central
148
KNOWLEDGE.
April, 1913.
slips can be got at directly, but if either of those at the
ends (right and left) is wanted we have to remove one of those
in the centre.
Figure 145 shows one of the empty trays, made thus.
First cut the base piece to fit easily inside the box. Now lay
four plain three-inch by one-inch
glass slips, centrally, side by side,
on the base piece, and run a pencil
line round the lot. Then cut four
strips of card (of thickness a trifle
more than the thickness of the
glasses) of such size as to fit the
card just outside the pencil line.
These strips will probably be
between one-eighth and three-
sixteenths of an inch wide, but
their actual size will depend on
the size of box in use. (Boxes for
quarter-plates vary a trifle in inside
measurement.) These four edging
strips are fixed to the base piece.
Then across each of the four
corners is fixed on a triangular
piece, so that the bottom or
underside of the base piece may be safely clear of the cover
glasses on the slips.
Practical points: (1) Use a sharp knife, preferably one with
fixed blade like an office knife. (2) Use a flat metal straight edge
for guiding the knife. (3) For cutting on, a piece of card is
good — perhaps the best of all things, as it does not blunt the
cutting knife point like metal or glass, and the card which is
being cut does not slip about. (4) For a fixing agent I vastly
prefer fish glue or seccotine. In the bottom of a small wine
glass put, say, half a salt spoonful of seccotine, add about one
third as much water and work up the mixture with a cheap
(penny) paint brush. This is also a
good tool for applying the adhesive.
(5) When one piece of card has been
stuck on to another lay the two
together in an old book for a few
minutes, to keep all flat until all is
fairly dry. (6) Do not use too much
adhesive. If any is squeezed out
between two pieces of card it is a
sign that too much is used. This
does not give such a good joint as
only just enough to cover the two
touching surfaces.
F. C. Lambert, M.A., F.K.P.S.
illuminators can be secured without expenditure other than
that of a small amount of time. -.
QUEKETTER.
DARK GROUND ILLUMINA
TION. — It may be of interest to
your readers to know that a dark
ground illuminator, for use with high
power objectives, can be made without
the underside of the top lens, as shown
grinding away
in the piece
of apparatus computed by Mr. Nelson in your March
issue. All that is necessary, is to place between the
top and next lens of the Abbe Illuminator, an opaque disc of
such a diameter as will cut off all the rays that directly enter
the objective. The simplest way is to take some tin foil and
begin by making a disc within a fraction of the diameter of the
upper side of the second lens — that is, the lens immediately
behind the front lens — of the condenser. This disc is then
rested on the upper side of the second lens and made to stay
in position by means of a little immersion oil or similar
material. The top lens is then screwed on and must be in
immersion contact with the underside of the object slide.
Now, if a one-sixth inch or one-eighth inch objective be used
on the object, which must be mounted in a medium other than
air, it will soon be seen whether the object or particles are lit
up with a black background. If no light passes, reduce the
size of the tin foil disc very slightly and repeat the experiment
until the desired effect is obtained. Each individual disc can
then be kept for the different objectives and a result equal to
that obtainable with the expensive immersion dark-ground
ON THE RELATIONSHIP OF APERTURE TO
POWER IN MICROSCOPE OBJECTIVES. — One
would have thought that the
late Dr. Dallinger had settled
the question of the value of
aperture once and for all
by means of the photomicro-
graphs, Nos. 7 and 8, on the
frontispiece to the last edition of
Carpenter ; but it seems an
obsession with some minds to
deny the obvious on this subject.
We can pass over Mr. Hutton's
references to dilettanti and ignora-
muses as opposed to workers and
savants and to opticians playing
to the gallery, as having no place
in a scientific discussion ; but he
should at least have stated the
Figure 144. facts correctly before indulging in
such expressions.
He gives the limit of keenness of vision as one hundred and
twenty-five lines to the inch because few eyes can measure closer
than this unaided. The question is not what the eye can measure
or count, but what it can perceive, and most eyes can easily
separate lines as close as a tenth of a millimetre. If anyone
doubts this, let him observe the scale on an eyepiece micro-
meter, with this ruling, in ordinary daylight.
He also assumes that no objective will bear more than a ten
eyepiece. However true this may be for the highest powers,
it increases up to at least twenty, or even twenty-seven, with
the lower powers of the same series.
His fundamental error, however,
is with regard to the total magnifi-
cation. The initial power of an
objective is always taken for an
image distance of two hundred and
fifty millimetres, and the image is
formed at approximately this distance
with the English tube, so that the
eyepieces being marked with their
actual amplifying power, the total
magnification is obtained by simple
multiplication. With the continental
tube the actual size of the image is
only about two-thirds of this diameter,
and, to make the result uniform,
the eyepieces are marked with
only about two-thirds their actual
amplifying power — a ten eyepiece
being really fifteen — so that simple
multiplication still gives the correct total.
Mr. Hutton has given the actual objective magnifications
for the short tube; but has taken the nominal figures of
the eyepieces as real and has, therefore, worked out his table
of apertures at two-thirds of the required figures.
A glance at Professor Abbe's table quoted by him on page 64
of Knowledge for February will show that the magnifications
are given for an image distance of two hundred and fifty
millimetres and the list of eyepiece powers given on page 63
are certainly only nominal.
This extra eyepiece amplification with the short tube makes
no difference to the quality of the final picture, as the
objective image is obviously correspondingly concentrated ;
but the objective must, of course, be corrected for the tube
length with which it is used.
Stated properly, the table becomes as follows with an
uniform eyepiece amplification of ten. I have given the
necessary apertures for a keenness of perception of both
one hundred and twenty-five and two hundred and fifty lines
to the inch.
It will be seen that even with an eye of half the usual
keenness and a ten eyepiece, the necessary N.A. for a one-
Figure 145.
April, 1913.
Table
31.
KNOV
Focal length
Initial
Total
N.A. for
N.A. for
of
magnifi-
magnifi-
125 lines
250 lines
Objective.
cation.
cation.
keenness.
keenness.
24 ram. or 1 inch.
10
100
•13
•26
16 „ „ I „ .
15
150
•195
•39
12 „ „ i „ .
20
200
•26
•52
8 .i ,i 3 >l
30
300
•39
•78
6 „ „ i „ .
40
400
•52
1-04
4 „ „ i „ .
.. 60
600
•78
1-56
3 „ it ft »
80
800
1-04
2-08
2 i, ,, 12 »
.. 120
1200
1-56
3-12
sixth inch is well towards what the best makers give, and for
a one-eighth inch and one-twelfth inch it is beyond the limit of
construction for dry and immersion lenses respectively, whilst
for a keen eye we already want an immersion for the one-
fourth inch, and with a one-twelfth inch could perceive more
than double the structure which it is possible for any cedar oil
immersion lens to resolve. For the lower powers a fifteen
eyepiece would enable us to use more aperture than any maker
has ever offered or could construct in a mount with the society
thread. Mr. Hutton's argument that high aperture is futile
because the eye cannot use it, therefore, fails completely.
His ideas as to the limit of useful magnification are equally
faulty. His formulae with the various denominators -26, -13
and -10 simply mean that eyes with the respective keennesses
of 250, 125 and 96 lines to the inch will require magnifications
of 577, 1154 and 1500 diameters respectively to define
structure as minute as N.A. 1-50 can resolve. There is no
need, however, to strain the eyes always up to the limit of
perception, and a sensible man will gain relief by using a
higher eyepiece whenever the objective will bear it. Thus, a
keen eye would require a five eyepiece to see what a one-
twelfth inch of N.A. 1-50 can resolve (120 X 5 = 600) ; but
would certainly use an 8, 10 or 12 for comfort. The point as
to empty magnification is that the limit aperture of N.A. 1-50
can as easily be given to a one-twelfth inch as to a one-
fiftieth inch, and as the eyepiece amplification required for
a one-twelfth-inch is only moderate, objectives of higher
power are quite unnecessary, besides being more difficult
to make and use, and far more costly.
The showing of the beads on Amphipleura pellucida has
nothing to do with the magnification further than is sufficient
to make them large enough to see. The lines usually seen are
from 92,000 to 95,000 to the inch, and require only N.A. -96
to • 99 to resolve them, although they are usually shown with an
oil immersion of N.A. 1-3 and oblique light as an exaggerated
diffraction effect. I have frequently seen them on what must
be a very coarse specimen, mounted in realgar, with the Zeiss
apochromats six millimetres for the long, and four millimetres
and three millimetres for the short tube, all of N.A. -95, with a
fourteen (actual) eyepiece for the first two and a ten for the
last. The images are absolutely identical, thereby proving
that the resolution is due only to the aperture ; but this
specimen cannot exceed 90,000 lines to the inch. The resolu-
tion of the beads is a far different matter. The cross lines
forming them are, according to the late Dr. Van Heurck,
127,500 to 130,050 to the inch and require in theory N.A.
1 -33 to 1 -35 to resolve them, so that they cannot possibly be
seen with N.A. 1-32 and any magnification. Visibility too, is
quite a different thing from resolution with such minute trans-
parent structures, and I believe they have never been
demonstrated with less than 1-40 N.A. aided by green light.
Dr. Spitta's plate is quite as good an example of fine manipula-
tion as it is of photography.
Mr. Hutton makes another mistake with regard to the
resolution given by photography in excess of white light. The
thirty per cent, is for the extreme violet and would require a
specially constructed objective. Blue light gives only eight
and a half per cent, over white, and the eye could perceive the
extra resolution as well as the photographic plate if it could
bear the intense illumination, or had the cumulative power.
The statement, amongst others, that Messrs. Leitz's photo-
graph at 1150 would give as much as the naked eye at 1400
is due to a misconception. The fact that N.A. 1 • 32 should
give as much resolution with blue light as N.A. 1-43 with
white, or rather yellow-green, is probably the statement
sought for. The magnification does not affect it.
The fact that some medical students prefer low aperture
objectives for their greater working distance and depth of
focus is no excuse for decrying so vital a property as aperture
on false premises. Those students who take their microscope
work seriously and desire to see all the structure there is in
their specimens will certainly obtain the highest apertures they
can afford in their objectives as soon as they realise that
resolution absolutely depends upon it, and will quickly learn
to substitute depth of focus by the use of the fine adjustment
and the natural accommodation of their eyes.
Nor need either cost or working distance deter them. It is
true they cannot as a rule afford apochromatics or even semi-
apochromatics, and it is not necessary. First class lenses of
high aperture can be bought at ridiculously low prices, and
are so near perfection in both performance and workmanship
that they are used for everyday work by eminent workers.
A two-third inch of a N.A. -30 for fifteen shillings and a
one-sixth in of N.A. -82 or an one-eighth inch of N.A. -85
for thirty shillings each can surely not be called expensive.
The first and either of the second will fill the battery for dry
lenses as they will each bear high eyepieces, whilst the
working distance of the one-eighth inch is fully two-fifths of a
millimetre over a No. 3 cover (quarter millimetre) and that of
the one-sixth inch a little greater. The student who is
clumsy enough for this to be a bar has a lot to learn before
he becomes a useful member of his profession, and if forty-
five shillings is considered too much to spend on them I
should like to know where he can get anything fit to work
with for less money. These are by a famous continental firm
and he cannot even get the lower apertures better than play-
things anywhere for less ; but if he prefers English make, any
of the first class houses supply objectives of similar aperture
and equal performance for a few shillings more.
It is the one-twelfth inch of N.A. 1-30 which is the
expensive item ; but there is no substitute, and in view of the
obvious fact that the corrections and workmanship must be
better in proportion to both power and aperture to give a
relatively as good performance and the smallness of the work
makes it difficult to get them even as good, there does not
seem much prospect of cheapening this item.
G. E. Garrard.
ORNITHOLOGY.
By Wilfred Mark Webb, F.L.S.
OVEN BIRDS IN THE ARGENTINE. — There is,
perhaps, no greater privilege for the naturalist than to
wander in foreign parts and observe at first hand the various
Figure 146.
An Oven Bird's Nest in a typical situation in the country.
150
KNOWLEDGE.
April, 1913.
creatures he has read of at home. It was recently my luck to
explore some of the little-frequented parts of the Parana, four
hundred miles up the river. Among the many
interesting objects were the famous Oven Birds,
of which there are various species. The com-
monest {Furnarius rufus) is a bird some-
what smaller than a Thrush, of dingy plumage
and with a continuous cry. The nests (see
Figures 146-148) are placed in the most
conspicuous positions — on the cross bars of
telegraph poles, window ledges, on monuments
in cemeteries, and on posts by the roadside,
and I have seen one built in a small back
yard on a post to which a clothes line was
attached. The clothes fluttering, the woman
passing to and fro, the children and dogs
playing around caused no uneasiness on the
part of the birds. No one ever seemed to
resent the intrusion of the birds in apparently
inconvenient spots — perhaps the charac-
teristic " slackness " of the people accounts
for the fact that the abandoned nests are
allowed to remain until totally disintegrated
by the weather.
The name Oven Bird is singularly appro-
priate, the clay nests bearing a striking
resemblance to the Spanish ovens in common
use throughout the Argentine. The natives
call the bird hornero (baker), or sometimes
casern, which seems to mean housekeeper.
There are two types of these nests ; one
kind having a large circular entrance (see
Figure 148), the other with the entrance
obstructed by a sort of half-opened partition
(see Figure 147). The nests are about a
foot high and an inch in thickness, and
weigh nine or ten pounds.
Lionel E. Adams.
Figure 147.
A Nest of the Oven Bird
with a valve-door.
PHOTOGRAPHY.
By Edgar Senior.
FADING OF SILVER PRINTS.—
Having had occasion recently to look over a
number of prints made by var-
ious processes some sixteen
years ago, and in which every
care was taken at the time to
make as lasting as possible,
such was the condition in
which nearly all of those in
which silver or its compounds
formed the image was found,
that we were forcibly reminded
of the fact that carbon and
platinum are the only really
reliable processes for per-
manency that can be depended
upon. It is only fair, how-
ever, to mention that those
of the prints which were made
upon collodio - chloride of
silver paper had withstood the
test of time and atmospheric
influences in a most perfect
manner, exhibiting no change
whatever that was perceptible.
As this want of permanency
in prints may be, and often is,
a serious matter, one is necess-
arily led to the consideration
as to what are the conditions
under which silver prints are
liable to fade. It has been stated, and no doubt with a good
amount of truth, that the combined bath method is responsible
Figure 148.
A boy holding the Nest seen in
Figure 146 ; note the open
circular entrance.
Figure 149.
A Spanish Mud Oven at Colastine
for a considerable amount of the trouble, as these baths usually
contain lead salts, added for the purpose of making the toning
more regular, and as no amount of washing
appears to entirely remove them, the ultimate
result is, that the whites of the print become
discoloured from the formation of lead
sulphide. Without in any way wishing to
uphold this method with the combined bath,
we must say that prints made upon Lumiere's
citrate of silver paper, and toned in such a
bath, remain unaltered after the lapse of
some years, not that this can be taken as a
proof of permanency. The question is :
are prints made by any particular method
liable to fade, and to what extent are they
likely to do so ? As a test of permanency it
has been recommended to photographers to
expose a print " in a moist atmosphere "
to sunlight for several days when absence
of change in colour was to be considered as
proof of permanency. This test, at most, is
very crude and incomplete, as prints which
have withstood it have changed under other
conditions. Then, again, many papers will
change in colour if exposed to sunlight for
a few days, some assuming a yellow, others
a greenish tint, and this alteration in the
colour must not be mistaken for fading of
the print. This latter is brought about by a
change in the silver image as the result of
chemical action upon it, and must be studied
from the nature of the silver print itself. It is
well known that although gold, and especially
platinum, remains untarnished by any atmos-
pheric conditions, silver, on the other hand,
readily becomes coated with a yellowish filth
of sulphide, due to the presence of sulphuretted
hydrogen or more complex compounds of
sulphur in the atmosphere, from the products
of combustion of gas, the burning of coal,
and the decomposition or decaying of organic
matter in the presence of sulphates, the action
of the hydrogen sulphide upon silver prints
in all probability being accelerated by the
presence of moisture. Other conditions which
would also favour chemical
action are increase in temper-
ature, and the state of division
of the bodies reacting. And
when the photographic image
is made up of silver in a fine
state of division, we can under-
stand why it is less able to
resist the action of such
bodies as sulphuretted hydro-
gen. Then, again, there are
many substances which,
though having the same
composition chemically, exist
under several modifications
having entirely different pro-
perties. Silver is one of these,
and this may account for a
certain kind of silver image
being more permanent than
another. In the case of a
silver print upon albumen,
gelatine, or collodio-chloride
paper, the image is probably
little more than a darkened
organic silver compound, while
that on bromide paper consists
of metallic silver. This may
be seen by examination under
a microscope, when the particles of silver will be readily
observable, whereas under the same power a printed-out
April, 1913.
KNOWLEDGE.
151
image upon silver paper would only appear as a continuous
stain. There is, therefore, a great difference between a
printed-out image and one produced by development. Then,
again, the former is much more readily affected by external
agencies, even prolonged soaking in water being sufficient to
very considerably weaken them. Then, if the cause of fading
be due to sulphurisation, the product formed may be an
organic sulphur compound of silver, as pure silver sulphide
itself stands the action of reagents very well indeed, and
bromide prints toned by means of " Hypo " and alum, " which
is a sulphurisation process," are remarkably permanent. It
may be remarked also that some bromide prints tone much
more rapidly than others, and examination under the micro-
scope shows that those which tone quickly have smaller-sized
particles of silver than the others, and this appears to bear out
the statement with regard to the state of division of the silver
and its influence upon the permanence of the image. If the
presence of hydrogen sulphide in the atmosphere is the most
destructive agent upon silver prints, then perfect toning
with separate baths of either gold or platinum is to be
recommended, as a good deposit of these should go far
to ensure greater resistance to atmospheric influences.
As a test of permanency prints may be subjected to the
action of sulphuretted hydrogen for a short time and the action
noted by comparison with part of a print not so treated. It
will be found that any prints toned with the combined bath
will bleach first, then albumen prints, after which gelatino-
chloride and collodio-chloride, and, lastly, bromide. There is
still one point, however, which has not been touched upon,
and that is the influence of the mountant upon the permanence
of silver prints. If prints are kept in a damp atmosphere, the
mountant may, from decomposition, liberate hydrogen in its
nascent state, when, if any " hypo " remained in the print,
sulphuretted hydrogen would be formed, with the result that
the prints would be affected. This, no doubt, accounts for
many prints which have not been mounted lasting longer than
those which have, and is an argument in favour of employing
a method of mounting in which a material that is not affected
by moisture is used. In conclusion we may say, that whatever
may be the exact nature of fading in silver prints, sulphur in
some form appears to be the prime cause. That collodio-
chloride appears less liable to change than some other forms,
is the conclusion arrived at from experience, although there
appears no theoretical reason why this should be, as the
medium itself cannot be considered as making much difference.
PHYSICS.
By Alfred C. G. Egerton, B.Sc.
RECENT LECTURES.— The results of physical investiga-
tions have been expounded recently by their chief pioneers.
It seems the time of year is fitted not only to the planning of
new investigations, but the clearing up of past work. Among
the most interesting summaries of work accomplished which
have lately been given, the lecture by Professor Strutt, at the
Royal Institution, on February 28th, finds place. He showed
numerous experiments illustrating the phenomena caused by
active nitrogen. Active nitrogen is almost certainly nitrogen
in the atomic instead of the molecular condition ; when the
atoms re-combine to form molecules, then ordinary nitrogen is
again formed. The transformation of active into ordinary
nitrogen takes place with evolution of light of a yellow colour.
Such a transformation, contrary to usual chemical action,
takes place more rapidly at low temperatures, as was shown
in the lecture, by plunging a tube containing active nitrogen
into liquid air.
The nitrogen is made active by being submitted to an
electric discharge from Leyden jars or similar condensers :
ordinary pure nitrogen, freed from oxygen by passage over
phosphorus, is sucked through a discharge tube at a pressure
of about one millimetre of mercury ; the nitrogen, as it leaves
the discharge tube, passes into a wider tube, where it can be
viewed undergoing its transformation into ordinary form by the
yellow light emitted. When other gases, such as chloroform
or carbon bisulphide, are passed in together with the active
nitrogen, cyanogen is formed and gives out the characteristic
pinkish light of the cyanogen flame. The nitrogen, unlike
ordinary nitrogen, combines readily with most substances. If
the metals are heated gently in the active gas, they give out
their characteristic line spectra and form nitrides. Thus
mercury was shown to give a brilliant mercury arc effect and
form a very unstable mercury nitride, which decomposes
explosively on heating.
Now ozone and nitric oxide, when they combine under
similar conditions, also give out light, but of a much greener
hue, and repetition of experiments on active nitrogen in
Germany by certain investigators have been ascribed to the
production of ozone or nitric oxide from minute quantities of
oxygen contained in the nitrogen. But it must be allowed
Professor Strutt has freed his nitrogen from oxygen quite
satisfactorily. The active modification of nitrogen can be
destroyed by the catalytic action of a surface coated with
oxide of copper. A copper wire, coated with oxide, dropped
into a tube containing active nitrogen immediately extinguishes
the glow. It is necessary for the nitrogen atoms to collide up
to seven hundred and eighty times before recombination with
another atom occurs, in presence of a copper oxide surface ;
whereas only one collision of a molecule of ozone against a
silver surface is necessary to cause it to transform to an
ordinary oxygen molecule. Ordinary nitrogen can be con-
verted into active nitrogen by means of the ring discharge.
If the inner coatings of Leyden jars are connected to an
induction coil, and the outer to a coil of thirty or forty turns
of wire, electrical oscillations will be set up in the coil of wire,
which will ionise and induce currents in gases enclosed in
tubes at low pressure placed within the coil. Therefore, all
that is necessary is to fill a tube with pure nitrogen, at about
one or two millimetres pressure, and place it within such a
coil, in order to obtain it in the active condition and view the
glow given by it.
Another lecturer has gathered together Mr. C. T. R. Wilson's
work, which has rendered visible the paths of ionising
radiations. When Rontgen rays or the rays from radioactive
substances pass through air, they cause ionisation of the air in
their path : that is to say, air particles carrying positive and
negative charges are formed. Moisture will deposit from air
.overcharged or supersaturated with water vapour on either
dust particles or electrified ions, such as these charged
particles are called. Thus, if the air through which rays are
passed is supersaturated with moisture, the paths of those
rays will be marked by the condensation of moisture on the
ions produced in those paths. That is the principle of Mr.
Wilson's method of making visible the paths of such rays.
However, it is not easy to record such effects photographically:
much ingenuity has been displayed in doing this satisfactorily.
Mr. Wilson allows the base of the ionisation chamber, con-
taining the moist air through which the rays from radium or
the X-rays pass, to drop slightly whereby sufficient expansion
occurs to cool the air to the necessary point to cause the
moisture to be capable of condensing out on any ions present ;
at the same time as the expansion chamber base drops a ball
is released, which passes between a spark gap, and the spark
through a mercury arc gives sufficient light to illuminate the
condensed particles, and allow them to be recorded on a
photographic plate which has previously been focused on the
expansion chamber. The photographs obtained are very
remarkable ; the paths of the a-rays of radium are very distinct
and perfectly straight to within a millimetre or so of their
termination, when they often branch off for a short distance
at another angle. Presumably, the a-rays have been so
reduced in velocity by their collisions with air molecules, that
they get deflected out of their path. The results with p-rays
— the negatively-charged rays from radioactive substances
and the rays produced when X-rays strike against substances
— have much more irregular and meandering paths, and the
streaks on the photographic plates are much less dense than
those due to the a-rays, because the number of ions produced
are much fewer. It is indeed wonderful that the actual
paths of single particles, of which there are more than a
million million million in one cubic centimetre, can be made
visible and recorded on a photographic plate ; and it is a very
152
KNOWLEDGE.
April, 1913.
great feat to have accomplished the actual making visible of
phenomena which have only been investigated and understood
by process of reasoning ; things are understood clearest when
they are made to appeal to the visual sense.
Among other lectures of great interest may be mentioned
Professor Sir Joseph Thomson's lectures on the Constitution
of the Atom, which have just been terminated at the Royal
Institution. He expounded in these lectures simply and
clearly his view of the atom composed, as all now admit,
partly of negative electrons and partly of positively charged
matter. The atom possesses a central core of electrons and
an outer ring, and the maximum number of electrons in this
ring is eight. The number in the ring determine the valency
of the atom, and the vibrations (as of a conical pendulum)
determine the type of spectra emitted. It would be too much
to go into the subject in detail in these notes, and the same
also applies to the interesting account of the researches of
Professor Nernst, which he expounded on four evenings
following the 6th March, to a large audience, at University
College, London.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A.
A MOUTHLESS CARP.- -It seems strange that a fish can
live and thrive without a mouth. J. W. Fehlmann describes
this apparent simplification of life on the part of a carp four
years of age. Its mouth was absolutely shut and the same
was true of the anus. Yet there were numerous mayfly
larvae, crustaceans, pieces of plants and the like in the food-
canal. The animal must have not only breathed but fed
through its gill-clefts. We are not surprised to learn that the
carp showed no trace of fat, but to live for four years without
a mouth was certainly an achievement.
MOVEMENTS OF THE SEA-HORSE.— R. Anthony and
L. Chevroton have studied the attitudes and movements of the
fascinating Hippocampus, which is at once a fish of the floor
of the sea (benthos) and " arboricolous " among the sea-weed.
It fixes itself upright with its prehensile tail, and is helped by
its swim-bladder to keep the vertical position. It swims
vertically, or obliquely, using its pectoral fins, and the dorsal
fin usually helps. The dorsal fin is also used to steady the
animal when it is fixed by its tail. In moving towards an
object the sea-horse bends forwards a little and mounts
upwards. When it descends it stops the action of its fins.
There are many remarkable specialisations about this attrac-
tive little creature. Thus there are numerous individualised
muscles. The head is not in a line with the backbone, but at
an angle of 90°— 100° to it.
NATURAL HISTORY NOTES FROM BOLIVIA AND
PERU. — Mr. James Murray, who was naturalist on Sir Ernest
Shackleton's Antarctic Expedition, now sends some very in-
teresting notes from a very different part of the world — from
Bolivia and Peru. The rapidly-dwindling Echoja Indians have
great skill in wood-craft. The chief Wahshee could bring the
animals to him by uttering certain sounds, which did not seem
to be imitations. " On one occasion a deer was sighted.
Wahshee began a very loud and wild cry, and the deer came
slowly nearer and nearer, till it was only two or three yards
from us." " On another occasion it was a black monkey.
This time he used a quite different sound, a very plaintive,
weird kind of whimpering. The monkey began to climb down
the tree towards us, and came quite near before something
disturbed it."
MAGGOTS IN MAN. — Mr. Murray gives a grim account
of one of the common scourges of the forest, the Sututu
(Dermatobia cyaniventris), a two- winged fly, whose larvae
— about an inch long — occur in the skin of men and beasts.
They are like Indian clubs in shape and bear rows of
prickles. The presence of the parasite is usually first noticed
on account of the sharp pain caused by the prickles as it
moves. The chief Wahshee already alluded to seemed to be
able to summon the larvae out of the skin by making a
curious chirping noise with his mouth, but there is need for
sceptical criticism here. Worse than Sututu is the Screw-
Worm (Chrysomyia macellaria) also the larvae of a horse-
fly. Large numbers occur together in the skin about a
wound. They burrow restlessly and cause great pain. They
kill many mules and a few men, and are themselves singularly
difficult to kill. The great specific seems to be a medicament
called Cebadilla.
THE SCALLOP'S EYES. — Numerous well-developed eyes
occur along the margin of the scallop's mantle, and it is well
known that the bivalve is exquisitely sensitive to differences
of light and shade. Victor Bauer has made a series of careful
observations on Pecteu jacobaeus, and finds that one great
use of the many eyes is to direct the animal to the illumined
surface areas, where there is special abundance of the phyto-
plankton on which it mainly feeds. The scallop does not
steer when it swims, it gets its bearings by means of its eyes
before it starts. The eyes also help it to detect the movements
of an approaching enemy, and the stimulus leads to a shutting
of the shell-valves. The skin secretion of a starfish sets the
scallop a-swimming, and here tactile and chemical stimuli
operate. But the eyes are auxiliary.
COLOUR-SENSE IN BEES.— Very interesting experi-
ments by L. von Dobkiewicz throw a clear light on a much
discussed question and on a number of well-established but
discrepant facts. It seems certain that bees distinguish
different colours. But different colours acquire significance
for bees when the insects have learned that certain colours
are associated with certain nutritive advantages. The bees
are not " reflex-machines," they are not compelled by any
organic chromotropism to prefer certain colours to others.
They accumulate experience, and remember that certain
colours are associated with certain nutritive benefits. They
learn to save time by following certain colour-hints, but it is
not inconsistent with this that they are eager visitors of
flowers without any colour at all, but rich in nectar none the
less.
SENSE OF DIRECTION.— Edmond Bordage made a
study of digger-wasps and other insects at Reunion and
reached some interesting conclusions. He maintains, for
instance, that the wasps find their home again by taking
particular notice beforehand of the immediate surroundings.
As the Peckhams noticed, there is a preliminary scouting and
observation of surroundings before the insect quits the
vicinity of the nest. Bordage is unwilling to invoke a special
sense of direction in such cases.
OXYGEN-STARVATION.— Anna Drzewina and Georges
Bohn have made interesting experiments showing the indiffer-
ence of many marine animals to scarcity of oxygen. A small
shore-crab (Carcinus tnaenas) lived for twenty-two hours
in water with only a trace of oxygen, and soon recovered.
A pea-crab {Pinnotheres) survived for three days. A
small sea-anemone (Metridium dianthus) lived for four
days, and others {Anthea cereus) seemed to be quite normal
after four and a half. The little periwinkle (Littorina rudis)
was none the worse for four days of the oxygen-starvation and
a Polychaet [Phyllodoce laminosa) was living after thirty-
nine hours. The little starfish, Asterina gibbosa, recovered
itself after thirty-four hours. In most of these cases, the
animal was inert at the end of the experiment, but recovered
in the course of a few hours.
VESTIGES OF SCALES IN SIREN.— It is well known
that amphibians are almost always quite naked, thus standing
in great contrast to the scaly reptiles. The limbless Caecilians
which burrow underground are exceptions, for they have
numerous scales embedded in the skin ; and there are some
other exceptions, such as Ceratophrys, which has bony plates on
its back. The extinct Labyrinthodonts were also armoured. In
studying the mud eel, Siren lacertina, Margarethe Kressmann
has made a very interesting discovery. There are numerous
papillae in the deeper, firmer layer of the underskin or dermis.
They occur over the whole body, and although they are hidden
by the more superficial layers of the skin, their structure is
such that they are very reasonably interpreted as dwindling
vestiges of the scales which ancestral amphibians possessed.
ON THE FLORAL BLUE.
By P. Q. KEEGAN, LL.D.
THii origin of a colouring matter is technically termed
cbromogen, i.e., the precursor thereof, or the special chemical
constituent, whose presence in the corolla is necessary for its
production. Most vegetable colorations are derivatives of
what is called the aromatic series of organic bodies, and it is
known that as certain members of this series produce the
magnificent aniline dyes, whose spectacular effects are familiar
in theatres, and so on, so also other members of the same
series form the origin of the beautiful tints and hues which
clothe the flowers of the field and garden. The floral structures
(corolla, sepal, and so on), are built up out of a number of chemical
constituents, e.g., cellulose, wax, oil, tannin, mucilage, salts,
and so on, which may be withdrawn therefrom and separated
by chemical methods. The question arises — a most interest-
ing one to the inquiring mind — what is the particular com-
ponent of this structure to which is due the outcome of that
most enchanting adornment, the blue, red, or yellow floral
coloration ? We must, by diligent analysis and with inexhaust-
ible patience, turn over every clue ; we must test and examine
all the constituents, until we find some particular one which
unquestionably betrays its relationship to the aromatic series
of hydrocarbons aforesaid ; for we are assured that therein
will lie the true spring and fountain of all this floral glory.
We commence the research naturally by studying specimens
of plants which bear really true blue flowers, taking care, of
course, that we do not mistake a violet or purple corolla for a
really blue one. An astute chemist, who is well versed in the
analysis of tannic materials, can foretell where such a subject
is sure to be found. He knows that such and such orders of
plants — for instance, the Rosaceae or the Leguminosae — do not
produce blue flowers, and he can assign a reason therefor.
On the other hand, he is quite convinced that certain other
orders, such as the Campanulaceae or the Gentianaceae, can
assuredly do so, inasmuch as that particular constituent
called tannin is of a similar kind in each of the latter two
orders, but is widely different from that in either of the two
former orders. Which is as much as to say, that a kind of
chromogen exists in roses and sweet peas which does not
exist in gentians or bell flowers, and vice versa. True blues
exist in veronicas, salvias, verbenas, basil, solanum,
penstemon, nemophila, convolvulus, borage, hound's tongue,
and in all the orders allied to Gentianaceae and Compositae ;
but not in lupins, vetches, peas, vetchlings, geraniums, holly-
hocks, primulas, balsams, flax, and so on. In the blue flowers just
mentioned there is a chromogen, i.e., a tannin common to all
as detected by chemical analysis, whereas in the non-blues
this special substance does not occur. A noteworthy fact or
peculiarity is that while one series or order of plants contain-
ing this special colour-producing body may exhibit red or blue
flowers only in certain species or even in one and the same
plant, another series or species with the same chromogen
evolves nothing but red or yellow adornments. In fact, in
some cases — as, for instance, in begonias — a genus may be quite
capable of displaying an azure appanage, but its powers are
confined to that of red.
However, to come to details, it may be mentioned that the
parent substance of the blue flower is called caffetannin and is
imbibed in every cup of coffee we drink, whereas when we
drink tea we merely absorb something concerned in the pro-
duction of red camellias, for example. The chemist will
inform you that caffetannin exists in somewhat different forms,
and has a different composition, perhaps, in different plants.
Some say it is a glucoside ; others deny that ; and some others
again assert that it is a mere mixture of organic acids and
other substances. What is beyond question is that it contains
in its composition (molecule) more of what are called hydroxyl
groups than perhaps any other tannic compound known ; that
is to say, that where an atom of hydrogen might be found, an
atom of oxygen takes its place. Oxygen is an element essential
to the support of animal life, but it is also a supporter of color-
ation, yellow for less of it and blue for more of it. Moreover,
we can artificially produce a blue compound from caffetannin ;
but from any other kind of tannin save one, this cannot be done.
We have only to leave a solution of caffetannin freely exposed to
the air with a little chalk added, when we see the latter
gradually turn green, and then on pouring off the liquid and
adding some acid, a red solution is obtained very like the tint
of the foxglove corolla, and so on, and which, like it also, may by
a certain treatment be changed into a brilliant blue. By a
careful application of dilute solutions of an iron and a sodium
salt the dilute colourless solution of the same tannin can also
be induced to yield a most beautiful and persistent azure
liquid.
In fact, the complete analysis of any plant that contains
this tannin reveals in many ways that we are dealing with a
powerful colour-evolving substance. Then again, we observe
similar phenomena repeated when other plants, perhaps
belonging to widely different classes or orders, are taken in
hand. But however wide these taxonomic differences, we find
invariably one common feature, viz., the capacity to produce a
true blue flower. Moreover, this most remarkable feature is
absolutely independent of the status of the organism, of the
organic perfection or degradation of the species. The
gentians, for instance, with their feeble powers of assimilation
and their mycorrhiza infestation ; the Compositae deprived of
one at least of the chief factors of organic perfection ; the
Labiates more perfectioned than the borages or the solanums ;
the Ranunculaceae, Liliaceae, and so on, with types repre-
sentative of a special kind of organic debasement — all these
and more rise to the same high level of floral glory when they
unfold and hang out to sun and shower the " soft eye-music "
of the flaunting blue.
In fact, the blue corolla is caused by the comparative
strength and completeness of the process of de-assimilation
occurring there, and this, no doubt, is also the cause why in
some plants a certain kind of tannic chromogen is produced,
and not so in others. The protoplasm, in order to eliminate
from its molecule a tannin containing six HO groups, would
de-assimilate or oxygenise more completely than if it produced
a tannin with only four or five HO groups. Also, in
Gentianaceae with very numerous ovules, blue flowers of the
most brilliant description are frequently exhibited ; in Com-
positae with only one ovule they are comparatively rare and
never so effective. In the latter case, the de-assimilation is
not complete, various volatile oils, resins, and tannoids being
a common outcome of the process. It may occur, of course,
that the plant itself may produce in its green organs a large
quantity of caffetannin — for example, the common yarrow —
while the flowers are white or pale pink ; but this apparently
does not occur in plants with vigorous powers of reproduction
(e.g., gentians) wherein tannoids only appear in stem, leaf, and
root, the more complete and final products being found
exclusively in the floral parts. Therefore, in accordance with
this report herein set forth for the first time in this journal,
let gardeners cease from troubling to " evolute " a pure blue
flower on a plant incapable of constructing a tannic chromogen
containing less than a certain number of hydroxyl groups.
153
THE NEGLECT OF METAPHYSICS.
By J. E. CAIRNS, B.Sc.
The latter half of the nineteenth century beheld a startlingly
sudden advance of science unparalleled in the history of the
world before; a true Scientific Renaissance. It was the publi-
cation of " The Origin of Species " which probably pulled the
trigger and released the vast stores of energy which threatened
to change completely the face of the world ; but the mines
had been laid long before, and the time had at last grown
ripe for their discharging. The world called for men and the
men came. In biology, chemistry, physics, psychology, giant
intellects sprang to the fore ; discovery followed discovery,
theories were conceived only to be supplanted before their
birth, and the array of new facts grew so amazingly that the
mind was stunned and bewildered before the dazzling display
of treasures that were heaped before it. Though confounded
at first by its " sudden joy," the mind soon took on a some-
what calmer mood in which it could appreciate its new riches,
and it conned them over and over again with ever-widening
and ever-deepening delight, till at last the wild excitement of
attainment gave place to the wilder excitement of possession.
Then ensued a period of what to us now appears like intel-
lectual debauchery : a time of rash assertion, of bitter con-
troversy between those who were conceited with their
knowledge and those who were conceited with their ignorance;
a pitifully hysterical display of nouveanx riches, a cruelly
uncompromising attitude of oracularism.
In those days — they seem so long ago, though in truth so
recent ! — one heard on every hand the stupendous promises of
science ; that it alone was capable of explaining away all the
problems of the Universe, and that it would make for mankind
a bed on which to lay his perplexed head in peace, — a hard
bed perhaps, but surely preferable to the soft "pillow of
obscure ideas " on which he had dreamed so restlessly so
long ! Science was rapidly assuming the role of the fairy-
godmother, that unworthy role which Huxley so bitterly
deprecated.
So it was then ; and now, at the beginning of the second
decade of the twentieth century, what has it all come to ? the
sweat of the conflict, the paeans of the victors, the woe of the
vanquished — what has come of them all ? For now the
struggle is over, save for some inconsequential skirmishes that
still go on among those who have not yet realised that the
whole war was but the striving of phantoms over a shadow ;
it is over and forces have been reviewed, losses told and
trophies counted. And here both sides have found that their
losses proved to be their gains, and their trophies were so
stained with the marks of meaner passions that they were
ashamed to vaunt them. But what of the grandiloquent
promises that science made to its partisans ? Have these
been redeemed, and are the great world-riddles all answered ?
We know now the promises were vain ; the boasted
omniscience but the empty wisdom of intoxication. The
phase has passed, and now we know that science has not
answered, and cannot answer the clamouring questions
regarding human destiny. Soul, mind, consciousness —
death, immortality, God, — of these, the physical science that
has spoken so loudly for itself knows nothing. Indeed, it has
not even a satisfactory criterion of reality to apply to the
subject-matter of its own studies ; it assumes reality where it
knows only appearance. These other vitally important
questions it cannot in the very nature of things hope to
answer, and they are left to a few enthusiasts whose feeble
voices have been almost drowned in the swelling triumph
hymn of their brothers in the physical camp. There are
aspects of the universe which are not amenable to investiga-
tion by retort, microscope or galvanometer, and this the
physicist must remember and thereby calm his too-arrogant
enthusiasm.
Let us enquire for a moment into the grounds for this
enthusiasm of the scientific man — always meaning by that
term the student of the physical or material aspect of the
universe. At first sight these seem very solid, and the
enthusiastic assertions quite justifiable. We think of the
theory of natural selection ; of the discovery of radio-activity ;
of the hypothesis of the electro-etherial constitution of matter;
and the thrill of intellectual satisfaction we experience shows
us that these things are good for man to know. We remem-
ber wireless telegraphy, X-rays, the transmutation of the
elements, the possibility of utilising the almost infinite stores
of energy that is within the atom, and science becomes the
fairy-godmother again.
We cannot praise too highly the genius and the patience of
those who have learned these things from nature and given
them to man. The splendour of the results achieved by
modern science is fully appreciated by us all, and to the
modern scientific man all pay their homage. It is when he
is raised to be a brother of the gods, with his fingers on all the
springs that direct the cosmos, that justifiable enthusiasm
degenerates into rank hysteria.
For in these results, which as records of human ingenuity
are so splendid, no really vital interests are touched. True,
the idea of unity and of beautiful inter-dependence which
they give reflects back on our moral life and influences our
conduct ; but it is only a reflexion, not a direct effect. They
have made the great mysteries of the whence ? the why ? the
whither ? no clearer ; and these are for mankind the real
vital questions, to which the nature of Nature is only an
embellishment.
The value of the work that has been done in science none
can gainsay, but it sinks into comparative insignificance before
the value of the work that has not been done. For mankind,
the study of the physical universe is of great importance, but
still its importance is only secondary to the knowledge of the
things that are not seen but are eternal. Not that we want a
Comte of the spiritual, obstructing all knowledge save such as
seems useful. It is a conceited presumption that pretends to
be able to demarcate useful from useless knowledge. Our
insight — especially of us physicists of the West — is not
sufficiently clear to justify such a position. Yet at the same
time, while not absolutely decrying any knowledge, we may
easily see that some things are of more importance to mankind
than others are. And here is the parting of the ways ; this is
the question that splits the company, the question that
Herbert Spencer asked explicitly, and every other philosopher
asked implicitly — What knowledge is of most worth ?
Spencer answered this question to his own satisfaction by
the single word — Science ! This was, without doubt, the true
answer for the time. Science was then the knowledge of most
worth, it was the knowledge the world needed most. But it is
not the true answer now. The world has had its science, and
has thriven upon it ; but now, after a gorgeous feast, repletion
is approaching.
Science is growing stultified and engendering stultification.
Having neglected things of the spirit and concentrated its
attention on matter and force, it has become " of the earth,
earthy." Man is growing dissatisfied with the description of
himself in terms of chemical equations and mathematical
formulae, and nothing more. He knows there is something
more, and consequently is annoyed when his darling science
persistently ignores it, and sometimes denies it. And, as well,
there is a rankling vindictiveness against this science, which
cut the wings of his airy fancies thirty or forty years ago, and
left him to crawl along the ground since.
There is a feeling of unrest, of incipient rebellion ; a stirring
of resentment against the salt that has lost its savour. The
very men of science themselves are casting about after wider
things.
If we look plainly at the fact then we must admit that
science has failed. It has given us a world without a God, a
154
April, 1913.
KNOWLEDGE.
155
body without a soul, a life without an objective. But at the
same time we must also plainly see that this failure is not due
to science in itself, but to the extravagant claims that were
made in its behalf. It was thrust into the giant's robe, and
could not help but trip over it. It is rather remarkable to
think that the necessarily restricted range of physical science
was lost sight of by its most gifted exponents. The rule of
the game (so to speak) which arbitrarily assigned matter and
energy alone to scientific activity, neglecting any other forces
or entities that might exist beyond these — this rule was
forgotten by the very players who imposed it. After thus
consciously and willingly setting limits for themselves, they
went on to declare — some openly, some tacitly — that these
limits included the whole contents of humanity's intellectual
aspirations ! All that science could teach was all there was
to know !
The enormous success that resulted in this limited field is
the only extenuation — and a very poor one it is — for such
conduct. The scientific men in their sparkling progress
hustled a wondering world along with them, and for a time
all forgot that science represented only one aspect of this
scheme of things, and that the less important aspect.
But only for a time. The pace is now slackening and
cooler judgment is returning. The problems that science
cannot solve are coming forward once more, as they always
must do, to the front. Science must vindicate itself for
solving the world-riddles in terms of a godless universe, a soul-
less body, an aimless life ! And science is dumb and helpless.
It is not difficult to see, however, that had physical science
been supplemented by metaphysics, as it should be, this
impasse would not have been reached, but all the unanswer-
able questions which are now clamouring for answers would
have been taken to the metaphysists whose business it is to
answer them, For science has solved its own legitimate
problems, and solved them brilliantly ; it is only with the
problems of metaphysics that it has failed.
It would seem, then, that for us the knowledge of most
worth, the knowledge that we need most to study, is meta-
physics. The laws of the inter-relations of. matter and energy
we know fairly thoroughly ; but what constitutes reality ; the
nature of the Soul and God ; the influence of Mind on
Matter — we understand hardly at all, when we need so much
to understand them. These latter should be — must be, now !
— the subjects of human investigation ; and the results when
combined with our existing and ever-growing knowledge of
things physical will give us a conception of the Universe
far more likely to satisfy both the emotional and the
intellectual cravings of man than any extension whatever of
our science of to-day could do.
And in this investigation it would be well to remember that
there are in India and China peoples who have been studying
these matters for at least twenty thousand years. Their
science was hoary before ours was born. It is for the
twentieth century to witness the meeting of East and West in
scientific brotherhood, on terms of mutual instruction.
Let us then turn to the East whence cometh the light !
CORRESPONDENCE.
AN IDEAL MUSEUM AND ITS GUIDE.
To the Editors of " Knowledge."
Sirs, — I feel somewhat relieved to learn from the letter
signed by Mr. Francis Guy Laking, M.V.O., F.S.A., the
Keeper and Secretary to the London Museum, Kensington
Palace, which appears on page 93 of your March issue,
that he is in no way responsible for the guide. As you,
Sirs, rightly pointed out in your note, I had already made
this clear in my contribution. I must, however, express
surprise at the fact that the guide was never submitted to the
authorities, and, in the circumstances, still greater surprise
that these authorities yet permit the out-of-date, inaccurate,
and misleading guide to be sold at the museum to the public,
especially as these authorities are not enveloped in the
" entangling meshes of departmental red tape." I know of
no provincial curator who would permit this, and I am sorry
to learn that the Keeper and Secretary of this important
London Museum is not able to prevent it.
I thought I had also made it clear that I was not misled by
the so-called guide, but my remarks were based upon an
actual examination of the cases and their contents. I feel
flattered and gratified at being asked to give any suggestion
for the improvement and the arrangement of the specimens in
this important museum, and will certainly accept the kind
invitation to call upon the curator the next time I am in town.
A PROVINCIAL CURATOR.
THE FOURTH DIMENSION.
To the Editors of " Knowledge."
Sirs, — Mr. H. Stanley Redgrave, in a letter in your
February issue, expressed surprise that I did not go into
more detail in my reply to his statement that the existence of
one dimension implies that of a second, a second that of a
third, a third that of a fourth, and so on. I mentioned what
experience tells us in reference to dimensions, and pointed out
that there is nothing in this experience to support his state-
ment. In his letter in your March issue — in reply to the
letter of Mr. Henkel — he gives his argument in more detail,
so it is possible for more criticism to be made. -He asks what
can be the criterion of real existence which denies reality to
that which exists in mind. A single dimension has no real
existence in mind ; only the idea of it exists in mind. Our
knowledge of the real existence of anything must be based on
experience, and we have no experience of one dimension
except in conjunction with the other two. When the mind
thinks about one dimension it singles out one thing from its
experience and directs its attention exclusively to it, but this
action of the mind — or the idea in the mind — does not give
the one dimension any independent reality, or give any support
to an argument that the one dimension has independent reality.
In reference to his statement that nobody has ever seen a
three-dimensional body, it may be said that though any single
perception cannot give the knowledge of three dimensions,
there are very many perceptions — of various kinds — and the
accumulated result is experience. Certain kinds of inductive
reasoning — as exemplified in his letter in your February issue
— may be of use when finding out algebraical laws, but it is a
very different thing when it is a case of finding out what is,
or is not, in real existence. His statement — in the letter
mentioned — that the existence of n dimensions implies the
existence of »+ 1 is of the same nature as a statement that
if there are 50 sheep in a meadow there must be 50+1.
There is no evidence in favour of the real existence of the
fourth dimension and no evidence against this.
u M w JOHN JOHNSTON.
Hendon, N.W. j j
FOURTH DIMENSION.
To the Editors of " Knowledge."
Sirs, — I do not wish to enter on a controversy with Mr.
Redgrove as to the nature of reality, for I am inclined to
sympathise largely with much of what has been said and
written, and the matter is one about which philosophers have
always differed, and I suppose will always differ, from the days
of Plato to those of Bergson (who by the way owes much to
the former, though he does not acknowledge his debt to any
great extent). As a "working definition" perhaps one might
tentatively define reality as that which exists independently
of any human mind perceiving it, as we conceive the
" material universe " to do.
With regard to our seeing only flat surfaces apart from the
stereoscopic effect arising from our two eyes, I would assert
that without some depth (i.e., third dimension) no surface what-
ever would be visible. The nearest approximation, optical
images and excessively thin sheets of metal, (o be seen by me
or even distinctly conceived in my mind must have some
thickness as well as length and breadth, though the third
156
KNOWLEDGE.
April, 1913.
dimension may be as small as we please by comparison
with the others. Moreover, it is a matter of convention
which we call x, y, or z, but a fourth dimension cannot be
interchanged with any one of the others, any more than can
the time element (one-dimensional) be exchanged for it or them.
"The phenomena whose study is the object of Natural
Philosophy take place each at a definite location at a definite
moment, the whole constituting a four-dimensional world of
space and time " (Whittaker's " Aether and Electricity,"
pages 447-8) and a method of analysis may be (and has
been) devised, dealing with the theory of the aether and
other matters.
But the essential nature of the one-dimensional element,
time, is in thought at least so different from that of the others
that nothing can be inferred from this as to the existence of
a fourth dimension of space.
Bodies move in space and require time to do so ; perhaps,
after all, our knowledge is confined to moving objects, time
and space being more or less necessary mental concepts. Then
the number of dimensions we adopt for each is a matter of
convenience, the fewest necessary and sufficient to adequately
describe phenomena.
F. W. HENKEL.
THE JOURNAL OF ECOLOGY.
Within the next few days the first number of a new
natural history journal will be published — The Journal of
Ecology — which will be primarily the organ of the British
Ecological Society. The proposed formation of this Society
was mentioned in an editorial note in "Knowledge" for
February, 1913 (page 56), and has met with such a hearty
response — not only from botanists but from others, both in
this country and abroad, interested in Natural History in
general, including Zoology, Geology, Geography — that it has
been found possible to extend considerably the originally
proposed scope of the Journal, and at the same time to issue
it at a moderate price.
The Journal of Ecology will be published quarterly (March,
June, September, and December), at. an annual subscription
of 12s. 6d., post free to any part of the world. This subscrip-
tion carries with it the privileges of Associateship of the
British Ecological Society, including the use of a library of
ecological works which is being formed, the answering of
enquiries addressed to the Secretary of the Society, the right
to attend the indoor and outdoor meetings, which it is proposed
shall be held at different centres in Great Britain, and
participation in other advantages which are offered. The
membership subscription is one guinea, entitling the sub-
scriber to receive the Journal and to other associateship
privileges, and in addition to vote for, and serve upon, the
Executive of the Society, and to assist in shaping its policy
and directing its activities.
The first number of The Journal of Ecology contains
eighty pages, and includes many and varied interesting
articles.
The Editor has taken a wide and generous view of the
scope of Ecology — briefly stated, this embraces everything
connected with the relation of plants and animals to their
surroundings. So far as the animal kingdom is concerned it
is proposed at first to confine Animal Ecology to such topics
as the inter-relationships between plants and animals — in
itself a large field — but it is recognised that, logically, it is not
possible, nor is it desirable, to confine the concept of Ecology
to plant ecology as is usually done. In the present, as in
the past, the distribution and migrations of plants and of
animals over the earth are in many respects closely bound up
with each other, to say nothing of the many special cases of
mutually beneficial partnership (symbiosis in the wide sense)
and of other forms of interaction between the two kingdoms
of Organic Nature.
Following an introductory article stating the aims of the
new Journal, Professor F. W. Oliver, F.R.S., contributes an
interesting account of the vegetation of the new Nature
Reserve at Blakeney Point — the remarkable shingle beach
(see " Knowledge," January, 1913, page 1) and other
habitats in this locality now secured as a refuge for an
unusually rich flora and fauna — with remarks on the influence
of the animals upon the vegetation, Mr. Wilfred Mark
Webb, F.L.S., F.R.M.S., gives a useful and encouraging
summary of the progress which has been made, and the
organisations which are now in existence, towards the making
of Nature Reserves in this country — while the Editor reviews
a number of recent foreign publications regarding Nature
Reserves in various parts of the world. Dr. W, G. Smith
writes concerning the work of Raunkiaer on "biological
types " or " life-forms " of flowering-plants and their
distribution — thus bringing to the notice of English
readers, for the first time, some of the most fertile
and interesting new ideas and points of view that have
been introduced into the study of plant-life during recent
years ; this article will be of special value to field botanists,
and will indicate a fascinating line of work which they can
well take up with pleasure and profit to themselves and with
every probability of contributing usefully to the general
knowledge of plant distribution and adaptation. Mr. A. G.
Tansley, M.A., F.L.S., reviews the recent attempt of Drs.
Brockmann - Jerosch and Rube], two distinguished Swiss
botanists, to draw up a general classification of plant com-
munities, criticising certain aspects of the scheme proposed
by them and giving details of the various communities. Mr.
Clement Reid, F.R.S., and Mr. W. B. Crump, M. A. .contribute
articles originally read by them before the British Association,
the former dealing with the relation of the present plant
population of the British Isles to the Glacial Period, the latter
with the ecology of moorland plants and the phenomena of
wilting in plants generally.
In addition to these articles, occupying the first half of the
number, there are numerous other articles based upon recent
work published in this country and abroad, dealing with
Ecology in the wide sense and including plant distribution,
the study of individual plants and of plant communities, the
anatomy and physiology of plants where the facts discovered
bear directly upon the relation of plants to their environment,
nitrification and other aspects of soil-study, experimental
morphology, and so on. The Editor has succeeded in making
these review-articles thoroughly readable and easily intelligible
to general readers with little or no special knowledge of
botanical science — this is perhaps especially the case with
those dealing with coast, woodland, marsh and desert vegeta-
tion, and the biology of cushion-plants, of insectivorous plants,
of heather, and so on — while at the same time these summaries
of recent work will prove useful to botanists and even to those
themselves engaged in research work in plant ecology and
biology. Teachers, for instance, will find such articles as
those on desert vegetation, the glacial floras of Europe, as
well as those dealing with British vegetation, of the greatest
interest in connection with the teaching of geography as well as
nature study.
The editor of The Journal of Ecology (Dr. Cavers,
Goldsmiths' College, London, S.E.) is also secretary of the
British Ecological Society, and information regarding the
Society may be obtained from him. Subscriptions for the
Journal with Associateship (12s. 6d.) or with membership (one
guinea) of the Society should be sent to the Cambridge
University Press, Fetter Lane, London, E.C.
The number concludes with extensive lists of recent
literature on Ecology and cognate branches of study, and in a
list of " forthcoming attractions," inserted in this number, we
find promise of some interesting contributions which will
appear in subsequent numbers of the Journal. A special
feature will be a series of articles dealing with methods of
ecological study, which should prove of great value to those
wishing to take up this interesting line of study, since the
articles will be written by well-known botanists who have
specialised in the subjects with which they will deal.
REVIEWS.
AERONAUTICS.
Aeroplanes in Gusts — Soaring Flight — and the Stability
of Aeroplanes.— By S. L. Walkden. 184 pages. 4 folding
plates. 8i-in. X6-in.
(E. & F. N. Spon. Price 7/6.)
We have heard and read much about the stability of
aeroplanes, some that is good and much that is bad ; but in
almost all cases the stability considered is that of the
aeroplane in calm air, a condition in which it does not much
matter whether the aeroplane is stable or not, so long as the
control is easy.
Furthermore, the cases considered are those of machines in
which the surfaces bear definite inclinations to one another,
and retain definite shapes: that is, the whole machine is rigid ;
but Mr. Walkden opens up a far wider field with countless
possibilities, by considering the case of the non-rigid machine
which has a certain amount of elasticity introduced into its
construction.
The author breaks fresh ground in the very first page and
continues to do so throughout the book. To start with, a
gust is defined and it is shewn that the proper and scientific
measure of a gust is " the acceleration of headway " impressed
upon the flying machine, the word " headway " being used in
place of the cumbersome but more general expression
"velocity relative to the air." The use of this as the
measure gives us a well-ordered explanation of all the
questions connected with stability, stresses, and soaring
flight in disturbed air.
Throughout the book, pretty graphical methods are adopted
for displaying the author's arguments and results. Following
on a very complete analysis of gust effects, comes a fascinating
treatment of the problem of Soaring Flight. Many a reader
will look upon " ascending currents " as the only possible
explanation of soaring flight, but Mr. Walkden clearly
demonstrates that there are many other and commoner
conditions of the atmosphere capable of being utilised by a
bird, if not at some future date by a machine. For this
purpose, for example, what the author terms " Wheeling
Soaring " can be effected by making use of horizontal gusts,
or even of large horizontal whirls. That such gusts do always
exist and that Mr. Walkden's figures are quite ordinary, will be
recognised by anyone who has watched the motions of an
up-to-date wind-velocity recorder, which will shew that in
any wind there is, say, twenty or thirty times a minute, a
variation of perhaps from twenty per cent, to fifty per cent, on
either side of the mean.
This may serve to shew the new and instructive matter that
is to be found in Mr. Walkden's book. The whole arrange-
ment of the book is of the same high quality as the contents ;
it is well printed, with a very complete index, and the plates
are arranged so that they can be studied while reading without
turning back the pages. We congratulate Mr. Walkden on
this addition to science. -f yy K. C
ASTRONOMY,
Astronomy.— By G. F. Chambers, F.R.A.S. 335 pages.
350 illustrations. 8 coloured plates. 6iX4£-in.
(Hutchinson & Co. Price 5/-.)
Mr. Chambers is very well known as a writer of astronomical
handbooks. The present work is intended for " the man in
the street" who desires a speaking acquaintance with the
subject, without going into any abstruse questions. In one
respect the book may be unreservedly commended, viz., its
illustrations, which are excellent; they include some recent
photographs of comets and nebulae, and planetary drawings
by Antoniadi, Phillips, Bolton, and so on. It is a little
disappointing in the text to find the very important astronomical
progress of the last twenty years passed over so briefly ; most
of the book might have been equally well written thirty years
ago. There are also not a few inaccuracies. Thus on page
56 we have the old suggestion that the numerous satellites of
the remote planets compensate for the diminished sunlight,
though it has often been shown that the combined light of
Jupiter's or Saturn's moons falls far short of the light of our
Moon. On page 59 the axial poses of Venus and Neptune are
almost certainly erroneous. The latter is the pose of the
satellite's orbit, which is inclined some twenty degrees to the
primary's equator. Page 62, line 17, for axis-minor read
major. Page 64, the daily distances travelled by the planets
ought all to be doubled. Page 73, the light of Venus at
maximum is said to equal that of Sirius; it is really some
fifteen times greater. Page 83, Deimos, Phobos are generally
taken to be the attendants of Mars, not his steeds. The
original (Iliad XV, 119, 120), perhaps admits either inter-
pretation :
'fis <paro, Kai p Itttovs kc\eto detftov re (pofiov re
Zei'71'ii^ei', at'TOS 8'evre edvffero irafAfpavouvTa.
Which Pope translates —
With that he gives command to Fear and Flight
To join his rapid coursers for the fight'.
Page 84, line 5, for Venus read Mercury; line 12, for five
thousand read four thousand three hundred. Page 90,
line 26, for one hundred and ninety-four thousand read one
hundred and eighty- six thousand three hundred and twenty-
six ; line 32, for 60" read 46". Page 106, the words about the
suspected ring of Neptune and the guarded language about
the existence of the satellite might have been written
about 1850; they are ludicrous now. Page 118: it is
misleading to say that the Saros brings back solar eclipses
to the same regions after eighteen years. The region is
shifted 120° westward, but in the case of eclipses near the
poles the two tracks may overlap. The tracks are said to
move southward after a saros ; this is only true for ascending-
node eclipses ; in descending-node eclipses, of which 1914 is
one, they move northwards. Page 128, the shadow in 1914
travels from Norway to Russia, not vice versa. Same page,
the map in Oppolzer's " Canon of Eclipse" is quoted as evidence
that the eclipse of 1999 will not be total in Cornwall. But the
maps in the Canon only represent tracks of eclipses as circular
arcs, which do not claim to be accurate. Calculation shows
that the eclipse will be total in Cornwall.
Page 195 footnote, Sigma Octantis is stated to be some
distance from the south pole ; it is really only three-quarters
of a degree distant, much nearer than our Pole Star. Page 200,
no mention is made of the very important double-star work
done at Greenwich. Page 214, the eclipse theory of Algol is
no longer merely a suggestion, it is demonstrated fact; the
secondary minimum, when the fainter star goes behind the
brighter, has been detected by Stebbins. Page 232, the
phrases " White " and " Green " nebulae, objected to by the
author, are used to denote a very real difference of spectrum.
Page 323, axial rotation, for days, hours, minutes read hours,
minutes, seconds. It seems rash to give the short rotation
periods of Mercury and Venus without query, considering how
many astronomers support the long periods. Curiously
enough, the Canadian Handbook noticed below gives the
long rotation periods without question. The safest attitude
seems one of suspended judgment, the evidence being con-
flicting. Page 324, the period of Jupiter VII should be
260 days, of Jupiter VIII 738-9 days, not twenty-six months.
In conclusion, we may state that the chapter on the
construction of a small observatory is written with practical
experience, and is likely to be very useful. ^ ^ ^ q
157
158
KNOWLEDGE.
April, 1913.
The Observer's Handbook for 1913. — 72 pages.
7J-in.X5-in.
(Toronto : The Royal Astronomical Society of Canada.
Price 25 cents. (Is.)
A very convenient handbook, containing the same informa-
tion as our monthly " Face of Sky " ; also sunrise and sunset
tables for latitudes forty-four degrees to fifty-two degrees,
and an article on the Comets of 1912. In the table of
elements, page 53, there is a bad misprint. The mass of
Mercury is given as 0-476 of the Earth's; this, presumably,
should read 0-0476. On the same page, see the remarks in
the previous notice re rotation periods of Mercury and
Venus. Page 54, the periods of Jupiter VII and VIII should
be two hundred and sixty days and seven hundred and thirty-
nine days, not two hundred and sixty-five, and seven hundred
and eighty-nine days. It is curious how often early approximate
values of constants continue to be printed, when later ones
are readily accessible. Same page, the satellite of Neptune
is stated to be nameless ; many authorities now use the name
Triton, the adoption of which seems worthy of encouragement.
The work also_ contains star maps', with notes on the objects
of interest in each constellation ; also an article on " Recent
Progress in Astronomy," by W. E. Harper. This deals more
particularly with stellar parallaxes and proper motions and
star-drift. Some recent conclusions in these fields have an
important bearing on the structure of the stellar system.
A. C. D. C.
BOTANY.
Hutchinson's Popular Botany. — By A. E. Knight and
Edward Step, F.L.S. Volumes I and II. 588 pages.
721 illustrations, 18 coloured plates. 9f-in.X7i-in.
(Hutchinson & Co. Price 7/6 per volume.)
These two volumes should do much to encourage the study
of plants. They contain a great number of attractive photo-
graphs, many of which have been taken by Mr. Step, but it is
obvious that there are many details which can much more
easily and effectively be brought to the notice of the student
by means of a drawing or diagram ; and it must be said that
those by Mr. A. E. Knight which have been introduced serve
their purpose extremely well and are most clear. Mr. Step's
books are well known and appreciated, and it goes without
saying that he has brought forward in a most pleasing way a
multitude of points of interest with regard to flowering and
other plants. At the same time, the book is a serious one and
contains much valuable information. The structure of the
plant, the way it does its work, and the relation of the leaf to
its environment, make up the first part ; while floral forms and
their connection with the visits of insects, fruits, and some
account of the reproduction of ferns and mosses, go to make
up the second, which also contains a glossary of botanical
terms and an index. It appears that at the present day the
British public demands coloured plates, and nine very effective
ones have been introduced into each of the volumes. We
sincerely wish Mr. Step's work the success which it deserves.
W. M. W.
CHEMISTRY.
Elements and Electrons. — By Sir William Ramsay,
K.C.B., F.R.S. 173 pages. 7-in.X4|-in.
(Harper & Brothers. Price 2/6 net.)
This little volume gains an added interest from the recent
discoveries of Sir William Ramsay, Professor Collie and Mr.
Patterson, which indicate the possibility of building up
elements from the immaterial ether and transmuting them
into one another. These discoveries, in fact, add a further
chapter to the history of the atomic theory.
The outline of this history is here given so clearly that
even a reader without any previous knowledge of chemistry
could follow it. Starting with a brief description of the
notions of the ancients about matter, the author soon brings
his story to the atomic theory of Dalton, which during the last
century was practically unchallenged. It is true that specu-
lations upon the possible existence of a primordial form of
matter inevitably followed the discovery of the remarkable
periodic relationships among the elements, but it was not
until the disintegration of radium into other elementary
bodies was discovered that any definite proof was obtained of
the existence of something more elementary than the
'■ elements " as defined by the chemist.
Sir William Ramsay keeps modestly in the background
while sketching the wonderful discoveries of the last few
years, but the story gains much in interest from being told by
one who has helped to shape its course. r A M
Second Stage Inorganic Chemistry (Theoretical). — By
G. H. Bailey, D.Sc. Revised by H. W. Bausor, M.A.
Sixth Impression. Fourth Edition. 544 pages. 109 illustra-
tions. 7-in. X 5-in.
(The University Tutorial Press. Price 4/6.)
The fact that there has been a demand for yet another
edition of this book is a proof that it supplies a want. In fact,
as a skeleton outline of all the principal facts of which a
knowledge is required by candidates for the lower examination
in " Inorganic Chemistry," conducted by the Board of
Education, it could hardly be surpassed. Moreover, the
information is conveyed in such a clear-cut form that it
impresses itself upon the memory. The book should prove
useful not only to those studying for particular examinations,
but also to all students who need a general summary of the
principles of chemistry upon which they can base their further
reading. Hence, in a way, it may take the place of a course
of lectures, provided that it is regarded, like the lecture, as a
means of clarifying acquired knowledge. Unfortunately, this
type of book also shares with the lecture the danger of being
regarded as a thing sufficient in itself.
C. A. M.
Second Stage Practical Inorganic Chemistry. — By
William Briggs, LL.D., M.A., and R. W. Stewart, D.Sc.
Revised and enlarged by H. W. Bausor, M.A. Sixth Impres-
sion (3rd Edition). 206 pages. 13 illustrations. 7-in. X 5-in.
(The University Tutorial Press. Price 2/6.)
This book is the practical portion of the theoretical volume
in the same series. LiKe its companion, it deals with its
subject in a thoroughly utilitarian manner, and it should find
a welcome from all who are working for the examination in
question. The exercises are well-chosen and the directions
clearly described, and the student who works conscientiously
through the book will gain a good grasp of the general principles
of chemical analysis.
One cannot help feeling, however, that it is a mistake to
divorce so completely the theoretical and practical sides of a
science, and that, apart from examination purposes, it would
be more satisfactory to have the two portions incorporated in
one book.
The table of atomic weights in the appendix also calls for
criticism, for the numbers are rounded off and are prefixed
by a note to the effect that they are " sufficiently accurate for
the purpose of ordinary chemical analysis." Surely it is a
mistake to encourage a beginner to aim at a limited degree of
accuracy ; and, apart from this, the use of such numbers at
the outset will be liable to give the impression that the atomic
weights stand in closer numerical relationship than appears to
be the case from the recorded determinations.
C. A. M.
GEOGRAPHY.
Turkey and the Eastern Question. — By John Macdonald,
M.A. 92 pages. 6-i-in. X4i-in.
(T. C. & E. C. Jack. Price 6d. net.)
This fascinating little book is, if anything, topical ; at first it
seems merely so. But consideration shows it is the book for
the student of the political movements of the age, whose
opportunities for study are limited to morning half-hours
with his newspaper, for "the man in the street." It would
April, 1913.
KNOWLEDGE.
159
be a valuable text-book in schools, particularly in Scotland for
those reading for the Leaving Certificate in History. It will
long remain the concise analysis of the problems of the Near
East ; of making larger books there will be no end, few will be
more useful. It is Anti-Turk, but not partisan, and carries
conviction because its argument is built on sound foundations
of geography, ethnology and moral and economic evolution.
The first few chapters, the most impersonal, are thrilling.
They deal with the evolution of the Balkan Problem, and raise
a host of interesting questions. Next, the present situation
and its prophase are treated. The last three chapters, the
most interesting, discuss the future, and give an instructive
comparison between Turkish rule in Europe and in Asia, and
British rule in India.
To this volume one would wish a few words of preface. The
credentials the author now and then presents in the work
would be welcomed in a foreword, setting out his purpose :
one resents their intrusion into the text. A few dates given
prominently would help the reader to keep his bearings and
maintain his grasp. Phraseology requires amendment here
and there, as on pages 72 and 78. . „
Atlas of the World. — By J. Bartholomew, F.R.G.S.
56 pages. 39 maps. 6i-in. X 4i-in.
(T. C. & E. C. Jack. Price 6d. net.)
It is questionable whether an atlas is within the scope of
such a series as " The People's Books," or can attain its
general standard of usefulness. The plates are small, and
now atlases with larger maps are available at a price equally
low, while larger and more detailed pocket atlases may be
had for a shilling. Still, these maps are clear, well-chosen,
and quite up to modern standards. They may be of use, for
example, in reading other books of the series. The route-
chart of Europe is good, and in these days, when history is
a-making, a race-chart would also have been valuable. It is
a pity that the scale and the projection of each map are not
given ; particularly on account of the first plate, a note on
projection might have been included. Having issued an
atlas, it is to be hoped that Messrs. Jack will publish a
gazetteer as a companion volume or volumes.
A. S.
Dent's Practical Notebooks of Regional Geography. Book
J. The Americas. — By Horace Piggott, M.A., Ph.D. and
Robert J. Finch, F.R.G.S. 64 pages. 25 maps.
93-in. X7i-in.
(J. M. Dent & Sons. Price 6d. net.)
These notebooks seem to be intended for progressive use
in secondary schools and particularly in connection with the
geographies by the same authors. They are interleaved
atlases of outline maps, some with no detail, others with
contours at large intervals and rivers, in order that the relief
of the land may be brought out by shading, the drainage
worked out, and the whole correlated with climate and
political and economic development. Instructions are given
on each sheet for the use of the maps and the writing of notes.
Some of these appear to supersede the teacher as a thinking
being, and teachers who do think will ignore many of them.
There is, nevertheless, much useful suggestion and some fresh-
ness in these notes. An interesting feature is the inclusion of
squared-paper and data for the construction of economic
graphs — data, of course, which should not be used exclusively.
Unfortunately, the projection is only mentioned in some cases,
but for advanced classes its determination in each map would
be a useful exercise. Each completed notebook will at once
form the best record of the pupil's work on a Continent
throughout his school course and his best work of reference
for many a day.
A. S.
Memorials of David Livingstone. — 16 pages, 6 illustrations.
7i-in. X 5-in.
(Marshall Brothers. Price 6d. net.)
At present the name of David Livingstone is on every
tongue, and people are consulting how best they can pay a
tribute to his memory. It is fortunate there are those whose
imaginations go beyond tombs and columns as memorials of
the illustrious dead. Scotsmen are proposing to establish a
Livingstone Chair of Geography in one of their Universities;
Churchmen a Livingstone Medical Mission in the sphere of
his labours. But already a valuable memorial exists in
Livingstone College, Leyton, London, founded in 1893, " to
give instruction to foreign missionaries in the elements of
medicine and surgery," and so to add very materially to their
usefulness. This booklet, issued by the authorities of the
College, contains two portraits in colour of Livingstone, the
memorial poem printed in Punch after his death, and pictures
of the inscriptions on his tomb in the Abbey and on the tree, at
the foot of which rests the heart of the traveller. The
portraits will be valued by many interested in Livingstone,
and the purpose of the booklet is to bring before such the aim
of the College, and gain their help in an endeavour to raise
£10,000 with which to clear off a mortgage, make improve-
ments in the institution, and form the nucleus of an endow-
ment. A_ g
Cambridge County Geographies. — Forfarshire. — By
Easton S. Valentine, M.A. 160 pages. 148 illustrations.
4 maps.
Herefordshire. — By A. G. Bradley. 149 pages. 54 illus-
trations. 4 maps.
Middlesex. — By G. F. Bosworth, F.R.G.S. 165 pages.
58 illustrations. 3 maps.
North Lancashire. — By J. E. Marr, Sc.D., F.R.S.
180 pages. 74 illustrations. 4 maps.
Linlithgowshire.— By T. S. Muir, M.A., F.R.S.G.S.
142 pages. 33 illustrations. 4 maps.
Rutland. — By G. Phillips. 171 pages. 46 illustrations.
4 maps. Each volume being 7J-in.X5-in.
(The Cambridge University Press. Price 1/6 per volume.)
We have on several occasions testified to the excellence of
the County Geographies which are being published by the
Cambridge University Press. They are books which everyone
should read, for many matters of the greatest interest are
touched upon, and the word geography is taken to include
not merely the physical conformation and political administra-
tion of the district, but also the geology, the ethnology,
history, and many other details. We are reminded that at
Burley, in Oakham, Geoffrey Hudson, the celebrated dwarf,
made his appearance before King Charles I, served up in a
cold pie, and we also learn that, although he did not reach
more than eighteen inches in height until he was thirty, and
when he began to grow again never exceeded three feet six
inches, he had a most eventful history. On the roll of honour
for Middlesex we find the names of Francjs Bacon, and
Thomas Henry Huxley, while in the volume for this county
there is a very interesting account of the natural history of the
immediate neighbourhood of the metropolis. Sir Richard
Owen is claimed by Lancashire, as well as Sir Richard
Arkwright, and among the illustrations which embellish the
book on Linlithgowshire are pictures of Linlithgow Palace
(where Mary Queen of Scots was born) and the Forth Bridge.
W. M. VV.
ZOOLOGY.
The Teratology of Fishes. — By J. F. Gemmill. 73 pages.
6 illustrations. 26 plates. 123-in.X 10.1 -in.
(Glasgow: Maclehose & Sons. Price 15s. net.)
Till a few years ago structural abnormalities in animals,
with the exception of those occurring in certain parts of the
skeleton, were regarded by the systematic naturalist as of
little or no importance from his standpoint. Nowadays a
complete change of view has taken place, and in the present
work Dr. Gemmill points how such abnormalities in fishes
160
KNOWLEDGE.
April, 1913.
may indicate in a remarkable manner relationships to the
higher vertebrates which are not apparent in normal examples.
It is, however, to be regretted that he does not appear to have
pointed out as clearly as he might have done the nature of such
relationships. Trout and salmon, of which the young states
are to be procured in any quantity at the hatcheries, afford
the great bulk of the material upon which the author has
worked. How great has been the labour involved, may be
inferred from a study of the beautiful series of photomicro-
graphs with which the volume is illustrated. Facts of the
greatest value have, it is stated, been ascertained by this
detailed study with regard to the mode of origin and develop-
ment of the bony fishes ; and much interesting information is
likewise recorded with regard to the origin and nature of the
different types of monstrosity most commonly met with. It
should, however, be distinctly understood that the book is
essentially one for the professional morphological and
systematic student, to whom it will doubtless prove of the
highest value.
K. L.
The Vertebrate Skeleton. Second edition. — By Sidney H.
Reynolds, M.A. 535 pages. 144 illustrations.
5iJ-in. X 9|-in.
(The Cambridge University Press. Price 15/- net.)
Professor Reynolds' book on the Vertebrate Skeleton has
proved of such value that a second edition has been called
for, and in it an attempt has been made to bring it up to date.
Professor S. W. Williston has revised the section devoted to
reptiles, practically re-writing Chapters XIII and XVI, and
making other contributions. A number of new illustrations
have been introduced, and those students who want a succinct
account of the skeleton, whether external or internal, of verte-
brates, will have it ready to their hands. The beginner is
advised to start with the skeleton of the dog-fish, and then
pass to those of the newt and frog, and after to that of the
dog. Other skeletons which are described in detail are those
of the codfish, green turtle, crocodile and wild duck; the
remaining parts of the volume being devoted to the various
classes and general accounts of their skeletons. W M W
NOTICES.
PHOTO-MICROGRAPHY. — We have pleasure in
announcing that Mr. Edgar Senior will give a course of six
practical demonstrations on photo-micrography at the South-
western Polytechnic, on Monday evenings from 7.30 to
9.30 p.m., beginning on May 5th. Special attention will be
given to the photographing of etched surfaces of metals and
alloys, but the course will also be arranged to suit the require-
ments of students of geology and botany, and those wishing to
use their own microscopes to obtain photographic records.
PHYSIOLOGICAL HISTOLOGY.— Messrs. Carl Zeiss
are issuing in ten parts an illustrated book on Physiological
Histology of Man and Mammalian animals, each of which is
accompanied by ten microscopical preparations. The first of
these, which is before us, deals with the skin and cutaneous
organs and is exceedingly well got up, while the slides, which
we have examined, are excellent. We may add that the work
has been undertaken by Professor Doctor Sigmund, and the
English edition has been prepared by Mr. C. Lovatt Evans, of
University College, London.
THE LIGHTING OF OPERATING THEATRES.— Of
special interest to surgeons is the system of concentrating
light in operating theatres introduced by Mr. E. Leitz. In
the past, to get over the difficulties of lack of daylight, arc
lamps have been used, but these cause the hands and instru-
ments to cast deep shadows which may obscure the field of
operation and even the use of more than one lamp does not
do away with this entirely, while only a small fraction of the
light from them reaches the operating table. In the system
already alluded to the rays from one arc lamp are concentrated
upon the operating table by six separate reflectors and so
much light can be made available that an iris diaphragm has
been fitted to the apparatus for cutting it down.
THE NATURALIST'S DIRECTORY.— A new edition of
"The Naturalist's Directory" is now being compiled by Mr.
S. E. Cassino, Salem, Mass., U.S.A., and will be published in the
fall of this year. This valuable work has been published
every few years since 1880, and comprises the names and
addresses of all English-speaking Naturalists, as well as full
particulars of the subjects in which each is interested. Every
Naturalist who has not received blanks should send his name
and address and full particulars, as well as the names of any
friends and acquaintances. To those who are actively work-
ing at any branch of Natural History, the importance of
having their name in this directory is obvious, for announce-
ments of new literature in connection with their subject will
reach them, and they will be brought into touch with fellow-
workers in all parts of the world.
MESSRS. J. H. DALLMEYER, LIMITED, having
removed from 25, Newman Street to 19, 21 and 23, Oxford
Street, close to the Tottenham Court Road stations of the
Central London and Hampstead Railways, and near the
junction of Charing Cross Road with Tottenham Court Road
and Oxford Street, all communications for the show-rooms and
London Offices should be addressed to 19, 21 and 23, Oxford
Street, W.
In their new home this famous firm of Dallmeyer, established
for over fifty years, are showing a large and varied stock of
photographic lenses, cameras and shutters, kinematograph
lenses, telescopes, telephoto lenses, and so on, all of which
are of the high standard of quality which has made the name
of Dallmeyer famous throughout the world. As the firm
extends a cordial invitation to inspect its new premises, we
would advise all those who are able to do so to take an early
opportunity of paying them a visit.
THE ALCHEMICAL SOCIETY.— The third general
meeting of the Alchemical Society was held on Friday, March
14th, at 8 p.m., at the International Club, Regent Street, S.W.
The chair was occupied by the acting President, Mr. H.
Stanley Redgrove, B.Sc. (Lond.), F.C.S., and a paper dealing
with the interpretation of Alchemy in relation to modern
scientific thought was read by Mr. Sijil Abdul-Ali. The
lecturer pointed out that the alchemists in general appeared
to have adopted the Hermetic method of reasoning from
universal to particular judgments, although there were sporadic
indications in the literature of a quite scientific and rational
empiricism. The fundamental concepts of their philosophy
were, he said — (i) A " First Matter" or "Hyle," containing
implicitly the four elements which were subsequently to issue
in manifestation ; (ii) Four elements (viz., earth, water, air
and fire), which, by mutual combination, produced the three
principles (viz., sulphur, mercury and salt), whose varying
combinations gave rise to the different properties of bodies ;
(iii) A certain divine spirit or essence, called " The Soul of
the World," which was immanent in all created things ; and
(iv) A mediate spirit, called " The Spirit of the World," by
which the soul acted upon and was bound to its body (i.e.,
matter). The lecturer compared and contrasted these
concepts, in a most interesting manner, with modern scientific
theories concerning — (i) A possible dual Protyle, or first
matter; (ii) The solid, liquid, gaseous, and incandescent
gaseous states of matter ; (iii) Energy ; and (iv) The ether of
space. The full text of the lecture and an abstract of the
discussion which followed appears in the March number of
The Journal of the Alchemical Society.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
MAY, 1913.
THE RED-TAILED HUMBLE BEE.
A STUDY IN MIMICRY.
By G. W. BULMAN, M.A., B.Sc.
Among our seventeen native species there is none
more easily recognised than the Red-Tailed Humble
Bee, the Bombits lapidarius of science. Its large
size, black body and red tail, are sufficient to enable
even those who take little notice of such things to
know it when they meet it in the fields. Even in
Shakespeare's time it would appear to have been
differentiated from the other species. For when
Bottom, in " A Midsummer Night's Dream," wished
for a sip of honey, his command to Cobweb was,
" Kill me a red-hipped humble bee on the top of
a thistle."
And yet there is another bee so like it that it
requires some practice in diagnosis to detect the
difference. It is of the same size, and has also a
black body with a red tail. Yet there are points of
difference which enable the expert to detect the
mimic at once. It does not, far example, go busily
from flower to flower gathering honey to take home
to the nest. It only wants an occasional sip for its
own sustenance, and its idleness is quite apparent.
The wings are darker than in the Bombus, there are
no little baskets on the hind legs for collecting pollen,
and there is a curious shining, almost bald patch on
the upper surface of the abdomen. Had Monsieur
Cobweb killed it in mistake for the red-hipped humble
bee, he would have found no bag of honey. This bee
belongs to a group very near the true humble bees,
and sometimes known as parasitic humble bees.
different group and
Noting the striking
They have been placed in a
named Apathus, or Psithyrus.
resemblance we say, in the language of modern
zoology, here is a remarkable case of mimicry. And
when we learn that the mimic is a parasite on the
red-tailed humble bee, then, if we are believers in
the theory, we sav, " This resemblance enables the
parasite to enter the nest of the host more readily.
It has been acquired because those which possessed
it in the highest degree succeeded best in deceiving
the host, and so getting their young reared at its
expense." Shuckard, in his work on " British Bees,"
writes of these parasites thus : —
" Both sexes appear to have free in- and egress to,
the nests of those Bombi which they infest, without
any let or hindrance on the part of the latter, with
whom they seem to dwell in perfect amity."
The resemblance of the parasite in the case of the
Red-tailed Humble Bee is certainly _ striking, and
according to the above, perfectly succeeds in its
purpose of deception. Yet one asks, Why should
such a perfect resemblance fail in more than one
important point ? Why should this bald patch, and
these dusky wings, betray it even to a somewhat
casual observer ? A little difference in the way of
greater hairiness, or lighter colour in the wings,
would have been so easy, and likely to occur as
chance variations ! And then it has, as Mr. Sladen
says, "a distinctly lower-pitched and softer hum."
161
162
KNOWLEDGE.
May, 1913.
It gets its name Psithyrus, that is, " whispering,"
from this. If, then, it cannot quite deceive us, how
can it deceive the owner of the nest in which it
wishes to lay its eggs ? And in the darkness of the
nest where it probably first meets the owner, a
resemblance depending largely on colour would be
of little avail ! Moreover, are we not told that bees
recognise each other and strangers rather by smell
than by sight ?
Recent studies of the parasite and its host, how-
ever, compel us to change our point of view some-
what. For it does not appear to be the object of
Psithyrus to slip unnoticed into the Bombus
nest, and lay its eggs unobserved. According to the
account given by Mr. Sladen in his recently
published work, " The Humble Bee," it invades the
nest rather to fight with and kill the lawful queen.
The parasites, in fact, rely more on their " exceed-
ingly thick and strong skin, covering them like a
coat of mail and protecting them from the stings of
the Bombi." Moreover, being idle, they are further
protected by having no soft wax-yielding membrane
between the dorsal segments, as have the humble-
bees. The sting is also stouter, and more curved.
It does not appear, then, that the resemblance can
be of any advantage to the parasite, or that it can
deceive the humble-bee. Psithyrus, in fact, neither
requires nor makes use of its remarkable
resemblance.
Let us suppose, however, for a moment that the
resemblance were perfect, and that the Bombus
(jueen took the invader for another queen of her
own kind. What would happen ? We turn to Mr.
Sladen's book, "The Humble-bee," for an answer.
Some of the later-appearing individual queens of
the Red-tailed Humble-bee do not take the trouble
to start nests of their own, but enter those of others
to lay their eggs. At first the stranger is ignored,
but soon jealousy arises, and there is a mortal duel.
One of the queens is killed, generally, says Mr.
Sladen, the intruder. Thus the advantage to the
parasite of being like the host is more than doubtful.
Again, the Humble-bee shows by its different
behaviour that it recognises the parasite. " The
Bombus queen," writes Mr. Sladen, " on first meet-
ing the Psithyrus in her nest, shows a certain
amount of agitation and may advance to attack her,
but her courage failing she draws back." Evidently
the resemblance does not deceive her. And if it be
true that bees usually recognise each other by scent,
and that they, can in this way detect one of their
own species from a different nest, we need not be
surprised at this, however perfect the outward
resemblance. The first alarm of the Bombus queen
at the presence of Psithyrus is followed by a " kind
of despondency," and her interest and pleasure in
her brood seem less. In the course of time there is
a fight, and the parasite generally wins, sometimes
killing several workers which have come to the
assistance of their mother, as well as the Bombus
queen.
In the face of all these facts what becomes of the
theory that the mimicry of Psithyrus is protective,
and has been acquired as a useful character by
natural selection ? The resemblance does not
deceive the host, and it would apparently be no
advantage to Psithyrus if it did.
The resemblance, as Mr. Sladen tells us, is not
merely superficial, as in the case of bee-like flies.
Psithyrus is almost a Bombus in general structure.
And this suggests a close relationship, as if the
Psithyrus had been a Bombus which took to
parasitism — as individuals of certain species do
to-day. Thus, individual queens of the Red-tailed
Humble-bee, will, as we have seen, enter the nests
of others to lay their eggs. And, if this is so, then
it is the points of difference that have to be evolved,
and not the points of resemblance.
Having disposed of the Bombus queen, Psithyrus
reigns in her stead. She lays her eggs, utilising the
wax she finds in the nest, since she cannot make any
of her own. Her young are tended and fed by the
Bombus workers. Apparently, as a sort of protest
against the usurper, the latter begin to lay eggs,
though these would only produce males. The
usurping queen, in her turn, eats them ! It is
obviously her interest to do so, for thus the workers
will devote all their time to the rearing of the young
parasites.
And a very curious problem is suggested by the;
fact that the young of the Psithyrus queen are reared
by the Bombus workers. For there are no workers
among the parasites as there are among the Bombi.
And the difference between these workers or neuters
and the queens among the Humble-bees is believed
to be the result of diet. The workers must settle
which are to be queens and which neuter. If a
given grub is to become a queen, it must from a very
early age be fed with a richer diet. Yet the Psithyrus
female grubs all turn out queens ! Are they all fed
on the royal diet, or are they all fed on the more
meagre diet which some superiority of constitu-
tion enables them to turn to better account than
would the grubs of Bombus? In either case it
is curious that the Bombus workers should not
make a difference, feeding some for queens and some
for workers, as they would in the case of their own
kind. And it would obviously be to the interests of
the Red-tailed Humble-bee as a species if the
Psithyrus grubs were all fed on so meagre a diet
that they all turned out neuters. On the other
hand, the feeding of all on royal diet might be a
last effort at self-preservation — a vaulting ambition
which overleaps itself and falls, on the part of
Bombus. For might not one of the grubs fed
royally turn out a Bombus queen ? But the only
result would be the full complement of Psithyrus
queens. If, however, they thought to destroy the
parasite race by rearing neuters instead of queens
then the superior constitution of Psithyrus, thriving
on the more meagre worker diet, developed the
queenly character in spite of their efforts.
THE POWER OF CONTACT
By CHARLES E. BEN HAM.
Over a hundred years ago a memorable discovery
was announced by Volta, who claimed to have
proved that by the mere contact of a disc of copper
with a similar disc of zinc the two metals became
electrified, the copper negatively, the zinc positively.
Much dispute arose over the experiment : for though
Volta repeated it hundreds of times, always with
just the same result, many men of science would not
believe in it. It seemed to oppose the fundamental
doctrine of the conservation of energy and to suggest
the heresy of perpetual motion ; and so the " contact
theory " of electricity was rejected
on the principle that " it can't be;
therefore it isn't." It seems strange
that instead of arguing as to whether (f\
it was possible or not, the scientific
world did not try the experiment
for itself. It was an exceedingly
simple one, one that anybody can
try with a condensing electroscope,
and one that never fails to verify
exactly what Volta announced. But
instead of putting the matter to a
practical test, the learned world,
reeling quite convinced that there
must be a mistake somewhere, con-
tented itself with abandoning the Figure 150
contact theory as impossible, and for
gives up to the vessel that receives it a constantly
accumulating charge of electricity. This is but one
special case of a widely extending law, and it seems
probable that any two dissimilar substances when
brought into contact and separated, are charged
with opposite electricities. What is called
frictional electricity is another particular case of
the same law. When a piece of sealing wax is
electrified by rubbing it with flannel it is not the
force of friction that is converted into electrical
energy. The rubbing is only the means by which
two such non-conducting bodies
are brought sufficiently into contact
to produce the effect. It is for
this reason that frictional electric
machines involve such a wasteful
expenditure of force. An over-
whelming proportion of the energy-
used is merely wasted so far as
the direct production of electricity
is concerned. The electrical output
is only equivalent in energy to the
amount of force required to bring
glass and rubber into contact and
to separate them again. All the
f^=^
^N
a long time it remained universally
discredited in spite of the fact that anybody could have
easily demonstrated its truth at any time. At last
came Lord Kelvin, who took the wiser course of
repeating Volta's experiment. He did it in a new
and ingenious way, which avoided all possibility of
any other cause than mere contact coming into action,
and to his own astonishment, and that of the whole
scientific world, he found that Volta was perfectly
right. The discovery led him on to make other
tests, all of which com-
pletely confirmed the
mysterious and inexplic-
able fact that when one
metal touches another,
a separation of elec-
tricities occurs, one
becoming positively
charged, the other
negatively. Copper
filings passing through
a zinc funnel are each
in turn brought into
contact with the zinc,
and the falling stream
FlGUKK 151.
rest of the rubbing is labour spent
in overcoming resistance to such
intimate contact. The modern static
machines, such as the Wimshurst,
require no friction, but depend upon a different
principle, the principle of multiplying an infinitesimal
original charge by the process of induction. That
original charge is derived from contact, either
contact between a small metal brush and the tin
sector on the glass disc, or it may be by the mere
contact of that sector with air.
According to Volta's principle the electricity of
a battery of zinc and copper plates in acid water is
due not to the chemical
action of the acid on
the plates but to their
contact with each other,
the acid water merely
acting as a conductor
to enable the current
to pass. The chemical
action is to be looked
upon rather as the effect
than as the cause of the
electricity — an unfor-
tunate effect, indeed,
from one point of
view, because the acid
0
163
164
KNOWLEDGE.
May, 1913.
necessarily acts upon the metals and so limits the
life of the battery. Yet acid is necessary because
without it water is not a good enough conductor
for the current.
Whether Volta was strictly accurate in looking
upon chemical action as the result rather than the
cause of the electricity in a voltaic cell may be an
open question, but certainly his explanation may be
as good as the other, and it is noteworthy that it is
sometimes instinctively adopted even by those who
believe in the chemical theory ; for it is usual to
speak of the corrosion that takes place when zinc
and copper are rivetted together as being due to
electric action.
But what naturally will occur to anyone hearing
of the suggestion that zinc and copper give
electricity by mere contact and that the acid
solution is a mere conductor which is only
incidentally destructive of the plates, is the question,
why should not the metals be used without the acid
and a conducting way for the current be found by
uniting the pairs of metals direct ? In this way it
would appear at first sight as though we could get a
series of cells without any liquid conductor, and one,
therefore, practically permanent.
A moment's consideration will, however, show
that this is not practicable. If when zinc is joined
to copper a current flows from the zinc to the
copper, it is evident that by joining another pair a
current will be established in the opposite direction.
The following diagram, in which the arrows show
the direction of flow of the current from contact
electricity, will make this clear. : —
ZCZCZCZC, and so on.
— > — > — >■ — >
The contacts obviously involve currents in the
opposite direction which will neutralise the others.
Nor is any better result obtained if a wire of some
other metal, say iron, is used to connect the pairs.
In this case the effect is shown by the arrows in the
following diagram (the numbers representing current
intensity between the various metals) : —
11 ii ii
ZCIZC1ZCIZC.
— > — >- — >- — >•
2 2 2 2
In fact the following law has been abundantly
established : — When any number of metals are
placed in contact in a series that returns to the metal
it started with, there is always an equal development
of contact electricity in each direction and conse-
quently no flow of current either way.
However, it is said that Nature never locks a door
without also providing a key. The key or clue to
this problem consists in finding a uniting medium
for the pairs of metals which is non-metallic, and at
the same time free from chemical action, while
sufficiently conductive to allow electricity to pass.
Such a conductor is found in water. Its resistance
without acid is high, but still it has some conducting
power, while its contact electricity with the metals
does not appear to be sufficiently appreciable to
neutralise the flow. Reverting to our former
diagram the series will now be
Z C W Z C W Z C, and so on.
— > — > — >
It is evident that in an extended series, there being
a minute difference of electric potential between each
pair, there will be a considerable potential difference
between the extremities of the series.
The experiment ma}' be made with a hundred
test tubes in which copper and zinc soldered strips
are placed in order. (See Figure 150).
If these are filled with pure distilled water
practically no chemical action will occur, but the
ends of the series will be in so high a degree charged
with opposite electricities that the gold leaves of an
electroscope will diverge widely when connected with
either terminal. One end of the series will show a
positive charge, the other a negative charge.
So far from this being due to any chemical action,
it will be actually found that the potential difference
is greater when distilled water is used than when
acidulated water is placed in the tubes.
With a water battery of this form made of some
thousands of tubes, Leyden jars may be charged and
sparks of considerable intensity may be obtained.
The difficulties attending the construction of such
a series and of insulating each tube perfectly are,
however, very great, and when an extended series
numbering thousands is required it is more conveni-
ent to resort to what is called the dry pile, though it
is not strictly speaking quite dry ; if it were it would
not work.
The dry pile substitutes a connecting medium of
ordinary paper for the distilled water, and so slight
is the amount of moisture required for conduction
that the small quantity of water always present in
the pores of ordinary paper will suffice. For the
metal plates it is unnecessary to cut out metal
strips. Paper with a metal surface can be obtained
read)' made, either bronzed or tinned. Cut into
squares or punch into circles a series of bronzed
and tinned papers, keeping them in uniform order
so as to have the arrangement — tin, paper, paper,
bronze, tin, paper, paper, bronze, and so on, and the
dry pile is made. The heap is firmly pressed together
between two pieces of well-varnished glass for
insulation, and close contact is maintained either
by binding the whole round with tape or by gluing
a strong band of brown paper round it. The
terminals are strips of thin metal to which wires
have been soldered. A series made up of twenty
or thirty sections and well insulated will show
undiminished electric activity for years. The
energy will not be sufficient to give a spark, but
the attractive power of the terminals will keep a
small brass ball (suspended by a hair or fine silk)
oscillating between two bell gongs without cessation
year after year with no signs of exhaustion or
enfeeblement.
A valuable practical application of the dry pile is
found in an instrument for detecting minute
May, 1913.
KNOWLEDGE.
165
quantities of electricity. An insulated strip of gold
leaf is suspended between plates connected with the
terminals of a dry pile. The plates attract it equally,
and, therefore, it remains at rest, but the most
infinitesimal charge of electricity suffices to upset
this equilibrium and to make the gold leaf sway to
right or left according to the positive or negative
nature of the charge applied. This form of electro-
scope is of extreme sensitiveness, and has the
advantage of indicating the sign, positive or negative,
of the electricity present.
While contact is the source of electrification the
intensity of effect from a single contact is so
infinitesimal that for practical purposes it is
absolutely necessary to increase it. It has just been
shown how this can be done by connecting in series
a large number of contact-making plates, but this is
not the only way in which an increased difference of
potential can be brought about.
A second' means is by applying the principle of
nduction. When a charged body is brought near
an insulated conductor without touching it, and the
insulated conductor is momentarily earthed, it will
be found to have acquired an induced charge nearly
equal in amount to that of the inductor, though of
opposite sign. And this happens without robbing
the inductor of any of its electricity. In fact, by
repeating the process any number of induced charges
can be obtained without diminishing the electricity
of the source. This obviously affords the clue to a
way in which by a succession of induction processes
an accumulated charge of appreciable magnitude can
be obtained from even such an infinitesimal source
as that of a pair of metal plates in contact. Adding
together the induced charges they mount up to an
unlimited extent.
But this process of repeated additions is necess-
arily slow. Much more rapid is the increase if
instead of merely adding them they can be multiplied.
Two induced charges, when combined, are practically
double the inductor's charge. Two induced charges
derived from this double charge will, of course, give a
fourfold charge. Two from this will give an
eightfold charge, and so on. The rapidity of
accumulation on this doubling principle is astound-
ing. Double a charge and its products in this
compound interest way twenty-four times, and it
increases more than eight million-fold.
A very simple and pretty experiment will illustrate
this. Fix upright from the centre of a board a
disc of metal supported by a narrow insulating strip
of varnished glass. Provide two strips of similar
varnished glass a little wider than the disc's
diameter and in height not quite as tall as the top
of the disc, and let them have discs of tinfoil
attached near the upper part. The lower end of
each is glued to a block of wood, so that they can
be pushed along the board up to the inductor, one
on each side, the tinfoil being on the outer side of
the glass, i.e., away from the inductor. The
arrangement is shown in Figure 151.
The inductor, presumably by its mere contact
with the air, has an infinitesimal charge of electricity,
and this, solely by multiplied induced charges, can
be made to give out in a few minutes sparks half an
inch long. The effect is almost miraculous to the
uninitiated, as the electricity seems to come from
nothing. It really comes, not from nothing, but
from an imperceptible and infinitesimal beginning.
The modus operandi is as follows : — Push one of
the mounted strips close up to the inductor. Earth
its sector by touching it with the finger. It has
received an infinitesimal charge by induction,
equivalent to that of the inductor. Slide it away
and do the same with the second glass strip. Now
bring both up to the inductor and touch the top of
its disc. It will, of course, receive by induction from
the combined influence of the two strips a double
charge. Repeat the cycle and it will gain a fourfold
charge. Repeat the process twenty-four times and
the original charge will have increased some eight
million times, and by this time at each earthing a
growing spark will be heard and seen, and its
intensity will go on accumulating until it is limited
by the capacity of the three conducting discs.
This simple experiment illustrates very graphically
the underlying principle of practically every form of
electric influence machine, such as the Voss, the
Wimshurst, and Clarke's gas lighter. All these
machines merely provide for the rapid performance
of a cycle of inductions so arranged as to produce an
accumulation on the compound interest principle.
The original source of the electricity is always the
infinitesimal contact charge, generally that derived
from the mere contact of air with the tinfoil sectors
of the machine.
Lord Kelvin applied the same principle to a
Water-dropping apparatus in which two streams of
water drops pass through the middle of cylindrical
metal inductors, each drop carrying an induced
charge as it breaks away from the stream under the
influence of the cylinder. The drops give up their
charges to metal cups which by means of cross wires
communicate the growing charges to the inductors.
Starting with no appreciable trace of electricity the
accumulation rapidly multiplies and causes the
startling phenomenon of flashing sparks between
contiguous parts of the apparatus, and the accumula-
tion is only limited by the fact that the streams of
drops become so highly charged that they soon repel
each other with such force that they scatter instead
of falling into their respective receivers.
The same effect may be produced with two falling
streams of sand or metal filings. In every such case
the initial charge is derived from contact, and its
manifestation is due to the doubling principle
already explained.
In a very rough and general way it is possible to
estimate the voltage of the original infinitesimal
charge of a doubler. Reverting, for example, to
our preliminary experiment with the strips of glass,
it will generally be found that about twenty-four
doublings yield a half-inch spark. It may be taken
that every tenth of an inch represents roughly a
166
KNOWLEDGE.
May, 1913.
potential difference of ten thousand volts, so that
half an inch means fifty thousand volts. Now, the
twenty-four doublings represent an increase of eight
million times, so that the original charge may be
put at about one eight-millionth of this, or the one
hundred and sixtieth part of a volt. At the same
time the amperage, it must be remembered, is, even
in the case of the fifty thousand volts, practically
unappreciable, so that the high voltage obtained does
not mean practical efficiency, say for lighting or
power purposes.
These few experimental illustrations all demon-
strate the mysterious principle of the origin of
electricity from contact. They do not, however,
demonstrate how or why electricity originates from
contact. Here we come to the boundary line
between the known and the unknowable as far as
physical science is concerned. The rest eludes our
senses. We come, as it were, to the horizon line of
the phenomenal, beyond which lies the noumenal
that is not attainable by the material senses.
All that can be said is that it seems as if the law
of contact was in the case of electricity merely a
particular case of the operation phenomenally of
some very vast law that also makes itself manifest in
many other ways. The mystery that peeps out in
contact electricity ma}- in the noumenal world be
one with the mystery that eludes us when we seek
for the cause of many potent influences arising from
contact in quite other departments of human
observation, not only in chemistry and other material
sciences but in purely human energies. The power
of " the touch of a vanished hand " may be as truly
due to polar sympathies as the force that arises from
the contact of dead zinc and copper. And in the
great unity of things which it is beyond us to grasp
the hidden cause of each may be one and the same.
It may be that there was no mere playful conceit,
but a hint of profound truth, in those pretty
impromptu lines with which Dr. Herbert Mayo
celebrated the epoch-making discovery by Faraday
of electro-magnetism : —
" Around the magnet Faraday
Was sure that Volta's lightnings play,
But how to draw them from the wire ?
He took a lesson from the heart :
'Tis when we meet, 'tis when we part
Breaks forth the electric fire."
THE HORNET AS A PET.
By G. HURLSTONE HARDY.
I began to be interested in Vespa crabo, with the appearance
of which I was much impressed, in my early youth. It then
happened that I acquired a large triple observation hive, but
no honey bees. I had to be content with placing therein the
nests of several kinds of wild bees, of course, separately, and
studied their habits and those of their parasitic enemies.
One summer, when I had in hand two colonies of the large
common bumble bee, and was hopeless of acquiring hornets,
I determined to add wasps. With the assistance of two
schoolfellows I smoked and dug out a nest of three horizontal
combs. These we placed in the central hive, with a few
young wasps and the queen wasp. These young wasps had
very recently emerged, and could hardly yet fly ; however,
they cleaned and fed the young in the combs. We fed them
with jam, house flies, and other insects. In about one week
a sufficient brood of newly-hatched working wasps were able
to forage abroad and rear all the brood. Unfortunately, the
queen disappeared, and the community did not increase to the
normal size of a full autumnal brood. The most curious fact
observed was that certain lazy wasps made a habit of awaiting
at the alighting boards of their bumble bee neighbours, and
there beg to be fed. They never threatened the bumble bees,
who seemed willingly to feed them without realising that they
were fatally neglecting their own broods.
My wasps never entered the nests of the bumble bees, and
they did not resent being closely observed as long so the hive
was not shaken and was only approached from behind.
Many years later I observed hornets flying very late in
the summer evening about trees in Chiswick, but it was
some time afterwards, whilst I was casually walking down
Chiswick Lane, that I discovered hornets busy around four
straw hives in the front garden of a cottage. I entered and
asked the proprietor to let me observe them. I found that he
kept these hornets for pets, and that he had no bees. We
had a long conversation on hornets and again on another
occasion, but I regret that circumstances prevented my
visiting the locality for several years. When I did eventually
go there, my acquaintance was not to be found. I hoped to
establish colonies like his in my own garden at Twickenham,
but have never been able to do so.
I learned from my acquaintance much of great interest, and
I was confirmed in all my somewhat conjectural ideas about
the habits of hornets which vary much from those of their
cousins, the commoner wasps. Friends are apt to accuse me
of joking when I aver that the hornet is a gentle, inoffensive
creature very suitable for a pet ; but it really is so, and the
reason is easily explained. Accustomed to hunt high in the
tree tops she remains ignorant of the savagery of the average
school-boy and she seldom experiences the malice of man or
becomes aware of the trepidation of woman at the mere sight
of a wasp. Her services must be overwhelmingly beneficial
in woods and orchards. At midsummer she forages much in
the night. The honey bee gathers from sunrise to sunset but
works hardest in the forenoon and slackens towards evening.
The wasp begins an hour earlier and ends an hour later.
Now hornets work throughout most of the twenty-four
hours if the weather permits. When I visited ray
acquaintance in Chiswick Lane he had two hives
occupied by numerous inhabitants and one other by
a very young colony ; he lifted up the latter hive and
let me observe the queen at work. He said he felt no
danger whatever, although she was at that date being assisted
by her first brood of workers. I greatly desired to know how
he managed to have inhabitants for his hives year after year,
inasmuch as hornet colonies were reputed to be not like those
of honey bees, but like those of wasps, started anew each year
singly in a new spot by a surviving queen after hibernation.
He said that every year, since he had started with a transplanted
colony, queens had voluntarily chosen hives in his garden.
Having lost such a unique opportunity of learning more, I
regret that now I can only surmise that queen hornets either
hibernate in the old nest or inherit an inclination to frequent
the locality of their birth, habits which are both contrary to
those of the common wasps and bumble bees, though the
upholsterer bees and their nearest relatives do exhibit an
excessive attachment to the spot from which they emerge.
If ever I succeed in getting a colony of hornets, I shall
install them near the top of my house rather than near the
front door steps on the ground, as did my acquaintance. I
have no fear whatever of these innocent and useful creatures,
who seem quite willing to share our dwellings with us if
encouraged to do so, but a high elevation would suit their
habit of high flight.
EARTHQUAKES FROM A JAPANESE POINT OF VIEW.
By BLACKFORD LAWSON.
Member of the Japan Society.
No other country in the world probably affords such
facilities for the study of earthquakes as Japan, nor
is there anywhere else such necessity for their
scientific investigation.
Nearly one thousand four hundred of these
phenomena are recorded
annually in the whole of
the Empire, and in Tokyo
alone there are, on an
average, fifty earthquakes
that can be felt during the
year, or ahout one a week.
Earthquakes, as every
one knows, occur in all
regions adjacent to active
volcanoes, as in the neigh-
bourhood of Teneriffe,
Vesuvius, Etna, and Strom -
boli. which are simply the
safety-valves of a single
earthquake district. So
also Japan, Sumatra, Java,
and the islands of the
East Indian Archipelago
are liable to fearful earth-
quakes ; and geologists
say that much of Japan
would never have existed
but for the seismic and
volcanic agency which has
elevated whole tracts
above the ocean by means
of repeated eruptions.
It is, therefore, only to
be expected that it occupies
an unique position in the
world as regards seis-
mology. Consequently,
there is a special Chair
of Seismology and an
Institute attached to it in
the University of Tokyo,
mittee for the investigation of earthquakes, under the
direct control of the Minister of Education. Besides
this, all the provincial meteorological stations through-
out Japan are equipped with instruments for
recording and measuring earthquakes, and seismic
phenomena are systematically studied.
In the interior, the writer frequently met, in an
out-of-the-wav cave or on the mountain-side, mem hers
of the Seismological Society of Japan, originally
organised by Professor Milne, who, with their delicate
instruments set up, were mapping down every quiver
of the earth's crust.
Figure 152. Earthquake Crack three feet wide, made
during the great earthquake in the Yamogata prefecture
(North Japan).
ind also a special com-
A study of a map of the world will show that the
configuration of earthquake centres, as seen in India,
Japan, Java and Sumatra, is that of an arc, and that
in each case the earthquake region lies on the outer
or convex side of the arc, where the deformation of
the earth's crust seen in
the curvilinear form of the
arc shows that the strain
is greatest. Thus, in the
Himalayas, severe earth-
quakes take place on the
outer or steep side, rather
than on the concave or
Tibetan side ; and in the
case of the Japan arc,
great seismic disturbances
occur almost always on
the outer or Pacific side,
where the Pacific Ocean
forms the greatest area
of depression in the world,
and only small local
shocks originate on the
inner or Japan Sea side
of the arc.
After the great catas-
trophe in North - West
India on April 4th, 1905,
the Japanese Government,
ever eager to study earth-
quake phenomena at first
hand, sent their leading
seismic expert, Dr. F.
Omori, Professor of Seis-
mology at the Imperial
University, Tokyo (see
Figure 157) to investigate
and report on the nature
of the disaster. During
several months' stay in
Tokyo, the writer was
honoured by the friendship of this eminent man,
'and spent many delightful hours in his lecture-rooms
at the University, and also with his charming family
in their picturesque home. From Professor Omori,
she learnt that the appalling loss of life in Dharmsala
and the Kangra Valley was due to faulty construc-
tion, the houses being built of stones roughly piled
together without any good cementing material, and
surmounted by a heavy roof.
In construction the first point is to make the
foundation solid and as large as possible, because, if
weak, cracks will be produced. In two-storyed
buildings, the upper store}- suffers more than the
167
168
KNOWLEDGE.
May, 1913.
lower ones, the vibration being greater at a height
than at the base. Again, a structure may be very
heavy, but if built of bad material it can have no
Figure 153. The Earthquake- proof Building erected in
the grounds of the Imperial University, Tokyo.
resisting power, and it will simply " smash down,"
for good material and good construction are more
important than thickness of walls. Now, in the
Punjab the houses were built solidly enough, the
walls being two feet thick, but they were tilled up
with rubble and small stones, and were, therefore, bad
from an earthquake point of view.
Professor Omori speaks very decidedly with regard
to the responsibility of Government in the erection
of jails and barracks, and he used a stronger expres-
sion than the writer ever heard before on the lips of
a Japanese in criticising Occidental methods, when
he said, in conclusion: " It is almost criminal on the
part of the Government to build bad structures for
public purposes, such as schools, jails and barracks,
and my advice to the Indian Government would be
to build more substantially, always on a sure foun-
dation, with good binding either of wood or iron, and
to use good material, especially in the case of public
buildings."
In Calcutta, Professor Omori found that the
theory of the engineers was, that the soft soil of
Calcutta acted as an elastic cushion, and, by absorb-
ing the earthquake motion, prevented it from being
communicated to structures standing upon it. Now
this was quite an erroneous idea, earthquake motion
being invariably felt more in soft than hard ground ;
and even within the confines of the city of Tokyo a
shock varies considerably, one in the upper part
being one-half less in intensity than it is in the
lower and softer parts. The same fact was also
made evident in San Francisco, where at the time
of the earthquake " made ground " and soft land
suffered more than the hard.
Speaking generally, the most important principle
in construction is to make the structure a single
body, simple and compact, avoiding the possibility
of different parts assuming different movements or
vibrations. For example, chimneys are dangerous,
because a chimney vibrates differently from the
main building, and in the event of earthquake it
will be found that a chimney is always broken at its
junction with the roof : so that, as the fracture of a
brick column occurs at a joint, its seismic stability
ought to be increased by using good mortar, until
the strength of the joint becomes equal to that of
the bricks themselves. In 1894 a curious earthquake
occurred in Tokyo, during which several chimneys
were knocked down in barracks, factories, and
schools, killing many soldiers and others. To
obviate this danger the Japanese now make the part
above the roof of light material, such as sheet-iron,
or better still, of earthenware (dokwari). As a
matter of fact, Tokyo is rendered generally hideous
by these iron chimneys — perfect abominations,
which tower above the roof-line, and are, indeed,
made so long that, when they fall, they do not crash
through the roof, but topple over into the street or
garden beyond.
In Japan, it is interesting to note that ancient
castle walls, built several hundreds of years ago,
have forms approximately equal to the curve theor-
etically giving the greatest stability against earth-
quake, known geometrically as the parabolic curve.
We find that the walls of all old castles are made of
parabolic section, thicker at the base, in the form
which mathematicallvgives uniform strength through-
out the height and prevents the formation of cracks ;
and, as a matter of fact, all these castles have with-
stood terrific shocks of earthquake.
There is no better example in the whole country
than the walls of Nagoya Castle (see Figure 154),
which are built of polygonal blocks, ten, twenty or
Figure 154. Nagoya Castle, one of the "sights of Japan."
The walls are of parabolic sections, to give stability against
earthquakes.
thirty feet long, uncemented, and fitted into the
bank at an even slope ; and yet, after hundreds of
years of storm and earthquake, there is scarcely a
May. 1913.
KNOWLEDGE.
169
crack to be seen. They withstood the great earth-
quake in 1892, when thousands of houses fell in
Nagoya and Gifu, and in the smaller places round
about, and when all the new brick telegraph and
post-offices and other European buildings came
crashing down like ninepins. On that occasion,
Japanese houses did not fall, unless they were old
and frail, when in many cases the supports gave
way and the roof came down, imprisoning the in-
mates until they were rescued, sometimes from a
house in flames. The walls of the Castle of Tokyo
show the same remarkable state of preservation, the
blocks of cvclopean masonry, there also uncemented,
being neither cracked nor displaced in the least
degree.
Figure 15.3 represents an earthquake-proof
structure erected in the grounds of the Imperial
University, Tokyo, which has been built according
to mathematical calculation on a solid concrete
foundation, and is intended for use as a Seismo-
logical Observatory, and as a standard with which
to compare the effects of a shock on ordinary brick
buildings. In it most interesting investigations
into the stability of various structures against earth-
quake shocks are carried on, artificial earthquake
motion being produced by means of a " shaking
table," which can be made to move with independent
horizontal and vertical motions by the use of steam
engines. (See Figure 158).
Another remarkable fact in Japan is that pagodas
(see Figure 155), built hundreds of years ago embody
the principle of the modern seismograph, which is
union of a stable and an unstable structure, to
produce a neutral stability which renders the whole
building least sensible to earthquake shock. In the
Figure 155. A typical Japanese Pagoda. It is a remarkable
fact that these pagodas, built hundreds of years ago, embody
the principle of the modern seismograph.
to minimise the effect of earthquake motion by the
combination of an inverted pendulum with an
ordinary pendulum; or, in other words, by the
Figure 156. A Japanese bell-tower, wherein the suspended
bell acts as a safeguard against earthquakes.
hollow well of every five-storeyed pagoda a heavy
mass of timber is suspended freely, like an
exaggerated tongue, from the top right to the
ground, but not in contact with it, and at the shock
of an earthquake this large pendulum slowly swings,
the structure sways, and then settles back safely to
its base. This is also the principle followed in the
construction of all bell-towers throughout Japan,
where the bell acts as pendulum, and the roof,
supported by posts, forms an inverted pendulum,
as in the seismograph. When an earthquake occurs,
a pagoda or a bell-tower may be rotated or dis-
placed, but it cannot be overturned as a whole.
Although seismologists have not yet succeeded in
finding out any means of definitely predicting the
occurrence of an earthquake, the}- are very hopeful
of finally arriving at this desired goal ; and already
Professor Omori, with his deflectograph and vibra-
tion measurer, can discern danger by careful
observation of the pulsations which are always
gently agitating the surface of the earth, and can
usually give ten or twelve hours' notice of a shock.
A sudden cessation of the regular heart-beats or
pulsations of the earth's crust is a danger signal,
extreme stillness invariably preceding an earthquake,
whereas constant tremors are a good sign.
A great earthquake is almost always followed by
weaker ones, and when it is violent and destructive
the number of minor shocks following it may
amount to hundreds, or even thousands, and
continue for several months or years. The
occurrence of after-shocks is quite natural and
necessary for the settling down into stable equili-
170
KNOWLEDGE.
May, 1913.
brium of the disturbed
tract at the origin of
disturbances, each of these
shocks removing an un-
stable or weak point un-
derneath. Further, as a
very great shock would
remove a correspondingly
great underground insta-
bility, it is probable that
such a shock would not,
for a long time, be
followed by another of a
magnitude comparable to
its own, in the same or
a neighbouring district.
When, however, the initial
shock is not very great,
it may be followed by
another like it ; but even
in this case the position
of the origin of the second
shock would usually be
quite distinct from that
of the first.
It is a matter of com-
mon knowledge that a
large part of the soil of
Holland, with its villages
and cities, is many feet
below the level of the
sea, and is slowly sinking,
while the Scandinavian
Peninsula is in process
of elevation. It is in
this way that the great
changes in the earth's
surface take place in the
course of ages ; and the
theory that mountain
ranges, like the Hima-
layas, were suddenly
thrust up by some world-
shaking, upheaval, has
long since been dissolved
by the light of experience
and investigation. But
while these mighty
changes have come about
unseen and unheard, the
petty shakings of the
seismic regions force
themselves in a terrible
way upon our attention,
as in the appalling disaster
of 1909 in Calabria and
Sicily, one of the most
awful of the recorded
earthquakes of the world.
Earthquakes are of such
common occurrence in
Japan that they are
hardlv noticed unless
Figure 157. ProfessorOmori with Vibrating Recorder at the
Seismological Institute, Tokyo. By means of this instrument
vibrations of railway bridges and steamers are measured.
Figure 158. "Shaking Table" in the Seismological
Institute. Tokyo University. The bricks are made specially
for testing purposes from brick columns previously des-
troyed by earthquake. They are pulled asunder in order
to find out the strength of the brick and mortar joint.
some damage is done,
and the writer was often
awakened in the night by
the bed rocking from side
to side, which sometimes
caused a slight feeling of
giddiness, like being at
sea. She was also un-
pleasantly reminded of the
forces at work at this
seismic junction of the
universe, when staying
in the Yamogata Prefec-
ture, in the north of the
main island, where an
unusually strong shock of
earthquake was experi-
enced. It lasted fully
three and a half minutes,
and although the house
in which the writer was
staying was not seriously
damaged, there were
cracks three feet wide in
the ground near the
windows (see Figure 152).
The building rattled and
swayed as though Samson
were beneath shaking it
as a terrier does a rat,
the surprised dogs outside
began to bark and the
cocks to crow, and the
feeling of mysterious
tremor or palpitation was
distinctly uncanny. At
the first indication all the
Japanese rushed franti-
cally into the street shout-
ing, "Jiskin! Jishinl"
(earthquake) and stood
huddled together in the
utmost terror until the
danger seemed over. The
.writer's own instinct was
to sit tight and cling to
the writing - table, but
presently shefound herself
sliding on the floor with
pictures off the walls and
bric-a-brac — ancient and
modern — strewn around.
In Tokyo people mention
earthquakes as we in
England do the weather,
when other conversation
fails, and thrilling tales
of personal experiences
during the most appalling
of nil the operations of
nature, are often told
round a dinner-table in
the metropolis.
THE EXISTENCE OF AN ULTRA-NEPTUNIAN
PLANET.
By PHILIP H. LING, M.Sc.
Thk discoveries of the planets Uranus and Neptune
were the first two steps in the outward extension of
our knowledge of the solar system. The third
step — the discovery of a planet still more distant —
is yet to be made. There is, however, a consider-
able amount of evidence for the existence of such a
planet, and in the present article it is proposed to
give a short discussion of the arguments which have
been brought forward.
It should be remarked at the outset, that visual
observation will play no part in the argument ; for it
is almost certain that no planet exists of sufficiently
large dimensions. We, therefore, have recourse to
indirect methods by studying the effects which the
hypothetical planet may be supposed to produce in
bodies which are themselves capable of being
observed. '
(1) The most obvious way of doing this is by-
examining the perturbations of Neptune. Now the
latter has a period of one hundred and sixty-five
years and has only been under continuous observa-
tion since 1846 — that is, for less than one half of its
orbit. It is obvious that no certain conclusions can
as yet be drawn from so small a portion of Neptune's
path ; and while the method may be useful centuries
hence, it is at present too precarious.
(2) A more hopeful plan is to study the perturba-
tions of Uranus. These are not completely explained
by the attraction of Neptune, and have recently been
examined almost simultaneously by Pickering* and
by Gaillot,+ working independently. They agree in
the mean distance of the unknown planet, which is
given as about fifty-two astronomical units ; but
Pickering finds the mass to be twice the mass of the
earth, while Gaillot makes it five times : the latter
also suggests a still more distant planet to be
required. The smallness of the mass militates
heavily against the correctness of the arguments
since the effects produced must be infinitesimal.
(3) The best method of all is that derived from
the orbits of comets. If we compile as complete a
list as possible of the periodic comets, arranged in
ascending order of period, a very striking fact
becomes apparent. They are seen to fall into
groups, the first of which contains those with periods
ranging from 3-3 to nine years, the second those of
period about thirteen, the third about thirty-three,
the fourth about seventy-three, while there seems to
be a fifth with period about one hundred and
twenty-one years. Now each of these groups
contains comets whose aphelia are approximately at
the same distance as one of the planets Jupiter,
Saturn, Uranus, and Neptune, while the fifth group
seems to correspond to a hitherto unknown planet.
There is, therefore, apparently some connection
between these groups of comets and the correspond-
ing planet, and before basing any argument on it, it
is necessary to inquire more closely into the nature
of the relation.
Now the most obvious explanation of the relation
between comets and planets, is that known as the
" capture " theory. ^According to this, at some
previous era the comet approached so closely to the
planet, that the gravitational attraction of the latter
was sufficient to overpower that of the sun, but not
large enough to transform the comet into a satellite.
The orbit thus became a long ellipse, with one focus
in the sun and the other in the position temporarily
occupied by the planet ; and this orbit would remain
permanent in the absence of commensurability
between the periods.
This appears to afford an explanation ; but two
difficulties, mentioned by NewcombL arise. In the
first place, Encke's comet has its orbit completely
within that of Jupiter, and no close approach occurs;
but we know that this comet probably passes through
a resisting medium, which is altering the major axis,
and it has been shown by Backlund§ that " capture "
within the last five thousand seven hundred years is
not by any means impossible.
The second difficulty is extremely serious. The
planets all move nearly in the same plane ; the
orbits of comets, however, are inclined to this plane
at all angles, and, as a result, though the statement
:;: See Nature, June 17th and August 26th, 1909.
I Comptes Rendu*, March, 1909. See Nature, July Sth, 1909.
[ "Encyclopaedia Britannica," 11th edition, Art. "Comet."
>' Royal Astronomical Society, Monthly Notices, LXX, 5, (March, 1910).
171
172
KNOWLEDGE.
May, 1913.
as to the aphelion distance above is still true, there
is, in point of fact, no close approach at all. This is
exemplified by Halley's comet, which, having its
orbit inclined to the ecliptic at about 18°, never
passes near the path of Neptune, to whose group it
belongs.
In discussing the difficulty, we must remark that
for " capture " to take place, it is only necessary that
the aphelion focus should be in the plane of the
ecliptic. Since this is not the case, there must have
been a secular rotation of the major axis, which had
moved the aphelion from its original position. If
this rotation does not exist, then the " capture "
theory must be abandoned. This applies to the
more distant comets, for Jupiter's group is generally
acknowledged to have been " captured," and in its
case the inclination is usually small.
It is interesting to notice in the orbit of Halley's
comet (the only distant comet which has been verv
thoroughly investigated) there was a divergence of
two days in 1910 between the actual and calculated
times of perihelion passage, so that an unexplained
rotation of the major axis certainly exists. This is
not to be referred to any known mass in the solar
system, while an unknown mass must necessarily be
very considerably out of the plane of the ecliptic to
produce the observed results.
At this point, much light is thrown on the subject
by a remarkable paper by Pickering*, which has just
appeared. If the translational motion of the solar
system through space experiences any resistance
from the ether, or from scattered matter, the effect
will be most visible in the case of comets, owing to
their small mass and large superficial area. The result
will be, that the aphelia will fall behind and will
tend to group themselves in a direction opposite to
that of the sun's motion. Pickering shows that this
actually takes place, and supposes that the diver-
gences which are visible are to be attributed either
to a motion of the absorbing medium, or to a curva-
ture in the sun's path. Here, then, is the explanation
of that secular motion of the major axis, which we
have shown to be required by the "capture" theory;
and the latter is, therefore, not inconsistent with the
facts.
The assumption of a resisting medium naturalK-
raises some suspicion, for there is a danger of using
it as a dens ex machina, in the way of solving
astronomical difficulties. But it certainly exists in
the shape of meteoritic swarms, even if the ether be
itself non-resisting, and it is now fairly certain that
the cause of the anomalous motion of Encke's comet
is to be found in this direction. We may, therefore,
conclude that if a group of comets exists outside that
of Neptune, it is a priori evidence for the existence
of a more distant planet.
Now, unfortunately, the evidence is rather meagre.
GrignelH examined twenty comets, and deduced a
planet at a mean distance of 50-61 ; but the periods
of the comets are very far from certain. Comet
1862 III (related to the Perseid meteors) is supposed
to have a period of one hundred and twenty-one
years ; while there has been stated an identity be-
tween the comets of 1532 and 1661. In 1911 it
was pointed out that there was a distinct similarity
between the Kiess and Quenisset comets of that
year and comets 1790 I and III respectively. If
this could have been established, there would have
been much stronger evidence for the hypothetical
planet ; but in each case the differences were such
as to lead to the conclusion that the similarity was
merely fortuitous. It is necessary, therefore, to
search for comets whose periods can be irrefragably
shown to be in the neighbourhood of one hundred
and twenty -one years, i.e., they must be seen at two
apparitions at least.
There have been one or two other investigations
concerning unknown planets. Pickering} stated
in 1910 that the orbits of comets and a certain per-
turbation of Neptune could be explained by the
existence of a large and very distant dark body in a
direction perpendicular to the ecliptic. Another in-
teresting suggestion is that of Professor Forbes §,
who gives some evidence for supposing that the
comet of 1556 was split into three in aphelion, about
the year 1702, by an ultra-Neptunian planet at the
the great distance of eighty-seven units.
The conclusion reached in this paper is, therefore,
that the orbits of comets present the most hopeful
method of arriving at the unknown planet, their
results agreeing roughly, as to the mean distance,
with those derived from the perturbations of Uranus.
The " capture " theory is, however, only rough ; and
for a proper treatment it will be necessary to discuss
in general the motion of a comet under the combined
attraction of the sun and a planet. These "parabolic
orbits," as the)- may be called (since, for a small
disturbing mass, they are. approximately parabolas),
present enormous mathematical difficulties, even
compared with the case of orbits nearly circular.
In the lunar theory, a revolution was effected by the
suggestion of G. W. Hill, to treat the question as a
particular case of the problem of three bodies and to
solve by series. The parabolic case is complicated
by the non-convergence of any proposed series, and
practically nothing has been done in the way of
mathematical analysis. Nevertheless, it seems to be
a necessary step in the establishment of the existence
of the unknown planet.
* "The Motion of the Solar System relatively to the Interstellar Absorbing Medium," Monthly Notices, Roy. Astr. Soc.
LXXII. (1912, Suppl. No.)
' See Nature, October, 1902. | See Science Abstracts, February 25th, 1911,
j Monthly Notices, Roy. Astr. Soc. December, 1903,
BIRD-CALLING.
By W. A. NICHOLSON.
The art of attracting wild birds is one little known
or understood except by those whose special interest
lies in this direction. The bird-catchers, and those
who trade in live birds, understand little, if anything,
about this subject, and even the bird-catchers them-
selves seldom prac-
tise it, reiving
almost solely upon
the live decoys
shut up in small
cages wherewith to
attract their wild
companions to the
deadly limed twigs.
One must be well
versed and possess
a thorough know-
ledge of the notes
emitted by birds,
besides being
acquainted with
their habits, before
he can employ the
aid of calls with success, and the pro-
fessional bird-catcher is an individual of
too indolent a character for this work,
which, doubtless, is the principal reason
he leaves it severely alone. Those who
use bird-calls regularly are the bird-
photographer, the field naturalist and
the wild-fowler, and all with the one
object and main purpose of decoying the
species and making them come nearer,
the first, to enable him to secure a good
negative and larger picture ; the second,
to extend his knowledge of the habits of a
species ; and the third to secure the
specimen. The wild-fowler, however,
makes use of few calls, often not more
Figure 159. Pheasant. Figure 160. Woodpigeon. Figure 161. Wigeon
Figure 162. Wigeon
(improved pattern).
than six, these usually being those imitating the cry
of the wild duck (mallard) (see Figure 167), curlew
(see Figure 164), golden plover (see Figure 163),
green plover, (see Figure 165), wigeon and teal (see
Figures 161, 162 and 171), and often two only are
regularly carried,
these being the
calls of the golden
plover and curlew .
As will be observed
from the illustra-
tions • which have
been reproduced
from photographs
of various patterns
in my possession,
that I make use of
regularly, there is
quite a collection
of different kinds,
a total of eighteen
being here repre-
sented. They are
all of Continental manufacture, but may
be purchased in England from Messrs.
Spratt's Patents, Ltd., 24, Fenchurch
Street, London, E.C. ; they are by no
means expensive in comparison to the
pleasure to be enjoyed by their use, and
cost from ninepence to three shillings
and sixpence each according to make
and finish. It is at all times advisable to
procure the very best that are made, for
the simple reason that with care they give
the finest results and will last for many
years. As remarked above, the successful
use of these calls chiefly depends upon
the operator and his practical knowledge
of the proper notes emitted by the birds
Figure 163.
Golden
Plover.
Figure 164.
Curlew.
Figure 165.
Figure 166.
Figure 167.
Figure 168. Figure 169.
Green Plover
Owl.
Wild Duck.
Hare. Hare.
(Lapwing).
(another pattern)
17J
174
KNOWLEDGE.
May, 1913.
in a wild state, and without experience of the latter
it will be only time wasted to endeavour to manipu-
late them, except, perhaps, with the exception of
two of the instruments, namely, that of the wood-
pigeon (see Figure 160) and the golden plover
(see Figure 16.5). These two are the simplest
to operate and little practice is necessary to
enable one to make successful
use of them. The woodpigeon
call may also be substituted
for that of the cuckoo, and a
little practice with it soon
enables one to acquire the
correct pitch and modulation
of sound necessary. It is
very interesting to visit a
breeding haunt of the wood-
pigeon with one of these calls
is to conceal myself (I use
Figure 170.
Partridge.
My method
a hiding tent
for this purpose, which is furnished with
tapes, to which I attach twigs, grass, and so
on, and make use of the surrounding under-
growth to screen it) under the nesting trees,
having previously arranged
my camera in position, and
send out a few notes. As
generally happens, the
cushats in the immediate
neighbourhood are cooing
all around, and, at first,
little or no notice is taken
by the birds of one's efforts,
but the secret is to continue
to call, not, however, unin-
terruptedly, but with pauses
of about four minutes, making
a fairly high pitch in the
tone, when the birds will be
observed to crane their necks
downwards and stop cooing
others fly closer to the
approaching to within a few yards, and altogether
Figure 174.
Magpie.
the call, always assuming the proper sounds are
given, has a most alluring effect on woodpigeons
during the commencement of one of their breeding
periods. During incubation, however, the birds pay
little heed to artificial calls, and at such times
it is useless trying to attract them. Another
easily duped species is the cuckoo, which may
be enticed to within a few
feet of the manipulator, and
the same may be mentioned
of the golden plover (see
Figure 163), partridge (see
Figure 170), pheasant (see
Figure 159), and little grebe
Figure 171. Figure 172. (dabchick). Species some-
what more difficult to deal
with are the wild duck
(mallard) (see Figure 167), curlew (see
Figure 164), snipe (see Figure 173), owl
(see Figure 166), wigeon (see Figure 161),
magpie (see Figure 174), oyster-catcher, and
IGURE 173. red-throated diver. All the calls illustrated
Snipe. should be worked with the left hand, so as
to leave the right hand free
for manipulating the shutter
of the camera and other
necessary items. The art
of bird-calling is a most
interesting study, possessing
a peculiar charm, a charm
impossible to describe, and
Teal
Figure 175.
Rabbit.
9
Figure 172
Blackbird.
Figure
Jay.
one
for
and
to
do
Having a
ornithological
with
Some bolder than
hidden caller, often
fold.
patience
certain.
fondness
pursuits,
plenty of time
spare, could hardly
better than take up
so absorbing a hobby, the
acquisition of which would
repay him a thousand-
Hut such a one must be possessed of great
and perseverance, otherwise failure is
176.
THE ANNUAL CONFERENCE OF THE PARENTS' NATIONAL
EDUCATIONAL UNION.
The seventeenth Animal Conference of the Parents' National
Fducational Union will be held at Caxton Hall. Westminster,
from May 5th to May 8th. The programme is now before us
and bears at the top the motto " Knowledge the basis of
National Strength." On the afternoon of the first day, Earl
Beauchamp will preside and Mr. J. St. G. Heath will give an
address on " Education and Social Sympathy." In the even-
ing, a paper on " Self Education," by Miss C. M. Mason, will
be read, and one on " How we teach Citizenship " by Miss
L. Faunce, an ex-student of the House of Education, Ambleside.
Tuesday morning will be devoted to the consideration of
the subjects taught in one of the Parents' Union Schools, and
among the other papers of the day wili be one on " Knowledge
and Learning " by Mr. Stanley Leathes, C.B. The topics
chosen for the third day include The Montessori System and
some of the ideals of the Union. In the afternoon, with Dr.
Parkin, C.M.G.. as Chairman, Mr. J. L. Paton, High Master
of Manchester Grammar School, will consider " Knowledge
and its relation to National Efficiency," while the Earl of
Aberdeen will preside in the evening, when the Bishop of
Southwark will speak on " The School of Life."
Papers dealing with the administration of the Union will
occupy the afternoon of Thursday, and in the evening there
will be a meeting for children's nurses, when Dr. Flora Murray
will talk about "Things that matter in the Nursery," and Miss
Helen Webb, M.B., will consider " The Child as a Person."
There will be receptions on Monday afternoon and Tuesday
evening. All particulars can be obtained from Miss E. A.
Parish, 26, Victoria Street, S.W., but we may mention that
season tickets, which admit to all proceedings, can be obtained
at a cost of 3s. 6d. each (invitations to the receptions will be
sent to holders of season tickets only), and day tickets for
Is. 6d. each.
WITHYWINDS AND WITHERSHINS.
By HARWOOD BRIERLEY.
An exact definition of the two strange terms, withy-
winds and withershins, is not easily given. A w ithe,
or withy, may be a flexible willow twig or osier, it
may be a band of twisted rings, or the spiral coil of
some plant-stem in the tangled hedgerow. The
poet's woodbine itself, better known as the honey-
suckle, is a typical winding withy, and, therefore, a
w ithywind. We call to mind the fact that there are
districts in which our great white convolvulus (C
sepium) is variously known as the hedgebell,
bellbine, ropewind, and withvwind. The latter
vernacular name is as appropriate as any, for this
plant's twisting stems are in some districts known
as " devil's garters," which, like the stem of the
woodbine, or honeysuckle, have been known to
strangle a fox in the brake after dragging at its
noose-like coils in a desperate attempt to extricate
himself. The "withershins" or " widdershins " of
Scottish literature is a compound of two Scandi-
navian or Gaelic words which have to do with
coiling stems and the sun. Originally a provincialism,
the term is now politely applied to some natural
object which elects to turn round in a direction
opposite to the sun.
Why do our weak-stemmed hedgerow plants turn
spirally in totally different directions ? The rule
commonly obeyed has, of
course, very few excep-
tions; and there is little
doubt that every indi-
genous climbing - plant
with corkscrew tendency
travels like the hands of
a watch, or follows the
sun as closely as it can
from east to west. Yet
some long acclimatised
species go the opposite
way, while some species
included in the same
genus are quite anti-
thetical in their feelings
on the matter. This
general habit of following
the sun must surely
depend on which hemis-
phere a plant's pro-
genitors first acquired
the instinct essential to
its welfare, and it may have been governed
by that same plant's desire to find either
light or shade. Overnight our convolvuli, bind-
Figure 177.
Stem of Convolvulus arvensis
twining to the left.
ir
&>
^3
tP^
Figure 178.
Stem of Hop twining to the
right.
weeds, bryonies, tarn uses, hopbines, and honey-
suckles become partially rigid in sleep, and more
supple again at sunrise, when they attempt again to
follow the source of
light around his orbit
from the east to the
far west of summer.
It is reasonable to
assume that a sun-
loving plant which
originated in the
southern hemisphere
would travel in an
opposite direction, from
right to left of the
observer. Unsuscept-
ible to the solar
influence is the tender
French bean, and the
contrariwise spirals it
makes proclaim it to be
a withershin. If you
unwind it from its
stick or post and
attempt to direct it
•aright, the snake-like
growing-tip casts itself free to hang stupidly
downward, and if the sap and cuticle have given
this bine a fixed "set" it declines to resume
its skyward journey, unless you place it in some of
its former contortions. Although you wrap it round
the stake in the direction it disdains, and tie it there
at intervals, it will not cease to make erratic twists
with new growth, until it can resume that eccen-
tricity of climbing which was established fast in its
nature, probably ages ago.
Convolvulus sepium, the great white bindweed,
may be called the typical withy wind (see Figure 177),
because of the fact that that name for it
belongs to the vernacular of one or more
southern counties. Although doubtless bearing
the largest and handsomest of our white wild-
flowers, which are bell-shaped and as pure white
as foam, it is yet unfortunately an emblem of idle-
ness in a garden lying waste, or it is at home on a
high hedge which rarely suffers from the slasher.
Like the cuscutas or leafless dodders worming their
network of delicate pink stems among furze, thistles,
and nettles, the numerous white bells hanging amid
masses of lovely sagittate or arrow-shaped leaves
which half smother the hedge afford some idea of
the lianas which form such a striking feature of
175
176
KNOWLEDGE.
May, 1913.
tropical scenery. On a smaller scale we have the
field-convolvulus (C. arvensis) with stem trailing
along wayside banks and field-borders, embellished
at intervals with pink and white-striped shallow
almond-scented cups, or often clinging to wheat and
barley stalks too tenaciously for any wind to unloose.
It is remarkable to find that so many spiral climbing
plants conform to the convolvulus type of leaf, all
of them being withywinds if not withershins.
The climbing polygonum or buckwheat — a
common and detested garden weed — and the
tamus or black bryony, with its glossy deep-
green leaves, have little in common beyond their
foliage, which features the convolvulus. This same
black-rooted bryony (Taunts communis) and the red-
berried bryony {Bryonia dioica) stand apart in other
respects than foliage, but, even more than the
vetches, the)- are both steadied by tendrils. The
climbing buckwheat certainly makes good use of its
small leaves to fasten it to a supporting plant. Its
fine, traily, stringy stem, branching out in all
directions, catches round stalks of corn, flowering
plants, and foliage, twisting them all together in
such a tangle that nobody could release them who
had not more than human patience, all being finally
borne down with the strain or weight. The convol-
vulus-like leaves are set singly at intervals, becoming
very small towards the top, till they look like
pygmean assegais. The growing tips are insinuated
through narrow spaces before the topmost leaves
open wide, whereupon the two broad lobes prevent
any slipping back when wind-shaken or dragged at
from beneath. From which it would appear that
some species of plants make their leaves answer the
purpose of tendrils.
Transgressing its own la wand the usages of climbing
plants in this hemisphere, we have known the bryony
— both the black-rooted and the red-berried — com-
mence its course aright, then halt, turn right round,
and proceed from west to east in withershins fashion.
We cannot conceive how such a plant comes to
infringe the rule of the indigenes, but there may
have been an obstacle in its path or some other
equally good reason for its "striking out a new line."
In fact, the bryonies are, even more than the bind-
weeds, now recognised to possess some of that in-
explicable knowingness or sentience which brings
them several stages nearer to the animal kingdom.
Your fancy may be mesmeristic or your volition void,
but your fingers can hardly cheat the bryony trailer
out of its own perceptions exactly where a suitable
support lies. Its sensitive leading tip squirms about
here and there till it secures a suitable grip, and if,
later, it comes to hesitate a moment, one may be
sure that the unforeseen has happened, or recent
conditions have changed, causing danger to lurk
ahead. One wonders what particular sense enables
the hopbine to repeatedly cross a three-feet space to
its nearest support after as many forcible dissuasions
by human fingers.
When the red-berried bryony gets enmeshed on a
hedge one has some difficulty in determining which
way its individual tendency is to travel. It may be
hurtful to the hedge, which was planted originally to
keep grazing cattle within bounds, but nature-lovers
forgive its faults because of those wonderfully
beautiful vine-like leaves which have been so
sedulously copied by decorative wood-carvers from
the earliest times of Art. The convolvulus type of
foliage is wholly departed from, here being five
fantastically cut, broad, vine-like lobes instead of the
usual couple which terminate with tool-like point.
Instead of a leafhold as with the climbing weed-like
polygonum there are tendrils, some of which will
stretch out for half a foot. When once they catch
hold they become a corkscrew-like coil or spring
which allows of sufficient " play " to escape damage.
I cannot say that I have ever seen any lonicera
or honeysuckle play withershins. But a man once
showed me a hazel walking-stick grooved out
spirally when still young and tender by Lonicera's
clinching hoop-like withywinds, which indicated this
plant's indebtedness to the sun as an agreeable
compelling-power. Here an individual plant had
studiously distinguished itself by an eccentricity, or
been compelled to fight for its own living in a novel
manner, by taking a wrong or retrograde turn in life
which led actually to fortune ! The hazel, its host,
is at first a sufferer, but, becoming a curiosity of
value by reason of the startling spiral impression,
gains immortality in the keeping of a collector of
walking-sticks, not the least of whom was our late
King Edward. Every conchologist knows the value
of a very rare variety of shell whose whorls are
termed sinister because they go the wrong way
round, and long ages ago a shell of this pattern was
supposed to bring luck to the finder or wearer, being
in this respect not inferior to the swastika symbol or
an}' other amulet. The sinister whorl of a shell and
a withywind's withershins, grooved in a stick from
the brake or copse, are corresponding freaks of
Nature.
The wild and cultivated hopbine (see Figure 178)
stands botanically apart from the honeysuckle, the
two bryonies, and other climbing plants ; but it is
nevertheless a true withywind, capable of extending
its growth by five inches a day. Although its
scientific name, Hamulus liipu/us, appears to be
based on a tradition of its being the " willow-wolf
which lives in a rich damp soil," and although it is
maligned as being able to strangle willows twenty
feet or thirty feet high, we really venture to believe
that the specific name " lupulus," is derived from
lupulin, the active principle in hops. If it were a
withershins to any great extent, we should certainly
have some records from Kent.
THE FACE OF THE SKY FOR JUNE.
Bv A. C. D. CKOMMELIN, B.A., D.Sc, F.R.A.S.
Table 31.
Date.
Sun.
R.A. Dec.
Moon.
R.A. Dec.
Mercury.
R.A. Dec.
Venus.
R.A. Dec.
Jupiter.
R.A. Dec.
Uranus.
R.A. Dec.
Ceres.
R.A. Dec.
Pallas.
R.A. Dec.
Greenwich
Noon.
,, IO
ii 15
h. m. 0
4 51*4 N.22'5
5 J2'0 23*0
5 32-8 2^3
5 53 '6 23 '4
6 14-3 23-4
6 35'i N.23'2
h. in. 6
5 26*9 N.28'2
io 24*0 N.i2*4
14 38 6 S. ig'i
19 27*0 S. 26*7
23 2\'B S. 4"7
3 9*1 N.21'9
h. m.
5 9'7 N. 24-1
5 56 '4 25-2
6 40*2 25-i
7 '9'4 24-2
7 53'5 22-5
S 22'^ N. 20*5
h. in.
2 s'2N.io'5
2 l8'2 II*I
2 32*7 I2'o
2 48*6 i3'o
3 5 '6 '4''
3 23'7N.i5-2
h. m. 0
19 1 1 '2 S.22'5
19 9"2 22"5
19 6 '9 22 '6
19 4-4 22-7
19 i*8 22"8
18 59-1 S.aa'8
h. m. o
20 39'6 S.i9'i
20 39*2 ig'i
20 38*7 19't
20 38"! 1 g" 1
20 37-5 t9-2
20 36*9 S.i9"2
h. m. c
15 iS'9 S.i2'o
15 15-4 I2'2
15 12*4 I2"4
15 9-9 127
15 8'o 13*0
15 6'9 S.x3'2
h. m. 0
14 25-2 N25"4
14 23'7 25"i
14 22 "8 24 "7
14 22 '4 24*2
14 22'6 23*7
14 23-3 N23-i
Table 32.
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Jupiter, L± refers to the
equatorial zone ; L2 to the temperate zone ; Ti, T2 are the times of passage of the two zero meridians across the centre of the
disc ; to find intermediate passages apply multiples of 9h 50im, 9h 55lm respectively.
The letters m, e, stand for morning, evening. The day is taken as beginning at midnight.
The Sun continues his Northward march till lh;» on
22nd, when the Summer Solstice occurs. Sunrise during
June changes from 3-51 to 3-49; sunset from 8-3 to 8-18.
Its semi-diameter diminishes from 15' 48" to 15' 45". Out-
breaks of spots in high latitudes should be watched for.
Mercury is in superior conjunction with Sun at beginning
of month, then an evening star, reaching East Elongation on
July 7th. Illumination full on 1st, one-half on 30th. Semi-
diameter increases from 2\" to 3i".
Venus is a morning star, at greatest brilliancy at beginning
of month, reaches West Elongation July 4th. 4J0 South of
Moon on 1st. Semi-diameter diminishes from 19" to 12".
At beginning of month 0-3 of disc is illuminated, at end of
month one-half. Being south of Sun, it is less well placed
for Northern observers than it was as an evening star.
The Moon.— New 4d 7h57me; First Ouarter lld4h 37m e ;
Full 18d 5h 54me; Last Quarter 26d 5h 41me. Perigee
10d 4hm, semi-diameter 16' 12". Apogee 25d 3hm, semi-
diameter 14' 48". Maximum Librations, 3d 5° E, 6d 7° S.,
18d 5° W., 18d 7° N. The letters indicate the region of
the Moon's limb brought into view by libration. E. W. are
with reference to our sky, not as they would appear to an
observer on the Moon.
Table 33. Occultations of stars by the Moon visible at Greenwich.
Dale.
Star's Name.
Magnitude.
Disappearance.
Reappearance.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.
"9'3
h. m.
h. m.
June 12
HAC 4200
6-2
8 55*
1090
10 o<
320°
,, 12
1JAC 4225 ...
63
11 16 e
66
11 52 i-
352
,, 13
62 Yirginis
67
10 7 e
73
—
„ 17
BAC5347
5'5
0 12 111
50
0 57 m
334
,, 17
HAC 5737
67
IO 16 e
So
,, IS
71 Sagittarii
var.
10 51 t
14S
1 1 ;6 t
216
,, 20
A Sagittarii
4'9
—
1 1 30 e
240
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
177
178
KNOWLEDGE.
May, 1913.
Mars is a morning Star, but not yet well placed for obser-
vation.
Ceres and Pallas are well placed for observation. They
are of magnitude 7 and 8 respectively.
Jupiter is a morning star. Polar semi-diameter, 2I2".
Table 34.
Day.
West.
East.
Day.
West.
East.
June 1
O 3124
June 16
3
O
24
2
.31
O 42
.. 17
32
O
'4
M 3
324
0 1
,. 18
3'2
O
4
» 4
43'
O c
» '9
4
0
12 3«
.. 5
4
O 3'2
„ 20
4'2
O
., 6
Ah
O 3
X 21
42
O
13
>. 7
42
O 13
II 22
41
O
23
„ 8
4
O 32 •
>. 23
43
©
2
.. 9
43'
O 2
,, 24
432
u
I
„ 10
324
O 1
.. 25
43'2
0
„ ir
3'
0 4 2©
,, 26
43
0
12
., 12
0 3124
„ 27
1
0
3 4«
" T3
12
O 34
„ 28
2
0
'43
., 14
2
O 134
,, 29
1
0
234
.. '5
'
O 324
„ 30
3
0
124
Satellite phenomena visible at Greenwich, ld 0h 36mm I.Oc.
K. ; 2h 24mm III. Tr. I., 2h 27mm III. Sh. E. ; 2d 2h 32mm
IV. Tr. I.,2h 39wra II. Sh. I., 4d lh 8mm II. Oc. R. ; 7d2h5mm
I. Sh. I., 2h 45mw I. Tr. I. ; 7'' llh27m ll"e I. Ec. D., 8d 2h 22mm
I. Oc. P., 3h 15mm III. Sh. I.; 8d 10h51rae I. Sh. E., llh 29me
I. Tr. E. ; 10d llh 28m 6"e II. Ec. D. ; lld3h25mm II. Oc. R. ;
lla WOme III. Oc. R. ; 12d 10h 28mc II. Tr. E., 15d lh 21m 14Bw
I.Ec. D.; 15d10h27me I. Sh. I., 10h 56me I.Tr. I.; 16d0h45m»ft
I.Sh.E. lh14mm I.Tr. E.; 16d10b33me I.Oc.R.; 18d2h2m576m
II. Ec. D.; 18d9h30m48"cIII.Ec.D.; 19d2h20mm III. Oc. R. ;
19" g" 54"c n. Tr. I., llh 57me II. Sh. E. ; 20d 0h 44mm II. Tr. E.;
22d 3h 15m 22'm I. Ec. D. ; 23d 0h 21,nw I. Sh. I., 0h 40mw I. Tr. I.,
2h 39mw I. Sh. E., 2h 58mw I. Tr. E. ; 23d 9h 43m 598e I. Ec. D. i
24d 0h 17mm I. Oc. R. ; 24d 9h 7me I. Sh. E., 9h 24me I. Tr. E. ;
26d jh 29m 2Vm lu Rc D . 26d 1Qh 46m 3gse IV Ec_ D
llh 43me II. Sh. I.; 27d0h 9mw II. Tr. I., 2h 33mm II. Sh. E.,
2h 59mw II. Tr. E., 3h30mmIV.Oc. R.; 28d9h3me II. Oc. R. ;
30d2h 15mw I. Sh. I.. 2h 23mw I. Tr. I.; 30dllh 38m 138e I.
Ec. D.
Saturn is invisible, having been in conjunction with the
Sun on May 29th.
Uranus is a morning star, coming into a better position
for observation.
Neptune is too near the Sun for convenient observation.
Meteor Showers (from Mr. Denning's List) : —
Radiant.
Date.
K.A. Dec.
Ma\'30to Aug.
333 + 28
Swift, streaks.
,, June
280 + 32
Swift.
,, to July
252 — 21
Slow, trains.
June to Aug.
310 + 61
Swift, streaks.
,, to Sep.
335 + 57
Swift.
,, to Julv
245 + 64
Swift.
,, to Aug.
3°3 + 24
Swift.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which
two hours will overlap with the following one. Thus the
present list includes R.A. 14h to 18h, next month 16h to 20h, and
so on.
Table 35. Non-Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Maximum.
U Urs. Min
b. in,
14 16
+ 67-1
7-6 to 12
d.
327
May 29.
S Bootis
14 18
+ 54 '3
7-710 13
273
July 9.
R Camelop ...
'4 24
+ 84 -2
7'2 to 13
269-5
June 3.
R Bootis
'4 33
+ 27-1
59 to 12
223-3
|une 19.
RR Bootis
14 44
+ 39 7
8-o to 13
iy6'5
May 18.
Y Librae
'5 7
- 5 '7
8-o to 11 '3
565
[une 12.
RS Librae
15 19
— 22 6
66 to 12
217
May 20.
RU Librae
15 28
-15 -o
8 4 to 1 1
314
June 24.
X Coronae
15 46
+ ;6-5
8-410 13
246
May 13.
R Serpentis . ..
15 47
+ 15 "4
5'6to 13
• 357
May 16.
RR Librae
15 5'
-18 -o
8'2 to 12-6
276-7
June 22.
Z Coronae
15 53
+ 29 '5
8 9 to 14
245
Mav 20.
T Coronae
'5 5°
+ 26-2
Now 9- 5
Nova Coronae
R llerculis
16 2
+ 18 -6
8'o to 14
3I7-7
Tune 23.
RR llerculis ..
16 2
+ 5° '7
7'8to 9-5
241
Mav 9.
U Serpentis ...
>6 3
+ IO '2
8-310 14
237-2
July 15-
SX Herculis ..
16 4
+ 25 ' I
7-9 to 9-2
■co '55
May 12.
W Coronae
16 .3
+ 38 -o
7 -8 10 12
244
July 14.
V Opbiuchi ...
16 22
— 12 -2
69 to io-8
3°2'5
Apr. 20.
R Draconis
16 33
+ 66 -q
6-4 to 13
245 ' 6
Inly 29.
Z Ophiuchi
'7 '5
+ 1 -6
7'5 to 13
348
May 10.
T Draconis ...
'7 55
+ 58 -2
7'5 to 12
426
Aug. 9.
RY llerculis
17 56
+ 19 "5
82 to 13
222-3
July 22.
NOTES.
ASTRONOMY.
By A. C. D. CROMMELIN, B.A., D.Sc, F.K.A.S.
THE SIZES AND DISTANCES OF THE STARS —
There was an interesting paper on this subject, by the
Astronomer Royal, at the March meeting of the Royal Astro-
nomical Society. He dealt with the faint stars within 10° of
the North Pole, as these were observed by Carrington, at
Redhill, sixty years ago, and have been recently re-observed
at Greenwich, so that their Proper Motions are well determined.
While the Proper Motion of an individual star does not give
us its distance, it is possible to obtain formulae giving the
relation between proper motion and distance for groups of
stars. The Astronomer Royal obtains a formula for star
distribution that fits the data from observation very well.
Extending his figures to the entire sky, he finds that there
would be three hundred and twenty stars with parallaxes
greater than a tenth of a second. The number with a
parallax greater than a fifth of a second would be one eighth
of this, or forty. It will be remembered that Mr. Eddington
recently gave a list of seventeen stars with a parallax greater
than one-fifth of a second ; a few more have since been
found, and it is likely that there are several stars with an
equal parallax that have not yet been studied for the purpose,
so that the two methods are in fair accordance. The
Astronomer Royal finds that a large proportion of the stars
discussed lie between parallax 0"-005 and 0"-0025, and that
ninety-five per cent, of them are intrinsically brighter than
the Sun. Mr. Eddington finds that in another region only
one per cent, of the stars in the catalogue he used are fainter
than the Sun. He points out that this does not mean that the
Sun really occupies so insignificant a place in the stellar host,
for if we consider the stars of large parallax, the Sun comes
quite high up on the list as regards intrinsic lustre. But
when we go out to great distances, the intrinsically faint stars
become too faint to come into our catalogues at all, and only
those of high lustre survive. At a distance whose parallax is
one-hundredth of a second, the Sun would be of magnitude
10-3, which is about the faintest included by the Astronomer-
Royal in his discussion ; at greater distances only stars of
great lustre are included, so that the catalogue is not a fair
sample of all the stars really existing in remote space.
Incidentally, the paper made a suggestion that a short name
should be given to the distance corresponding to a parallax of
one second ; the term " Astron " was tentatively put forward,
but Professor Turner expressed some apprehension that this
might be taken to mean the astronomical unit of length, viz.,
the mean distance from the Earth to the Sun. It is certainly
desirable to have a name both for this unit and for the other,
but it will be well to have a little discussion before they are
adopted. The Astronomer Royal urged that the "Astron"
should be generally used for stellar distances instead of the
Light-Year. In view of the large use of the Light-Year that
is made in many treatises on Astronomy, it is fortunate that
there is a simple relation between the two ; one " Astron " is
almost exactly three and a quarter Light-Years. The beginner
may like to see how this number is found. Light takes 498-2
seconds to travel from Sun to Earth. The number of seconds
in a year is 365JX 24X3,600 or 31,557,600. Divide this by
498 '2 we get 63,346 astronomical units in a Light-Year. ;: But
there are 206,265 astronomical units in an " Astron," this
being the number of seconds of arc in the unit of Circular
Measure. The " Astron " comes out as 3-2561 Light-Years,
but three and a quarter is near enough for all purposes. I
think the question of suitable names for these two units might
be a good subject for discussion in our correspondence
columns. Apropos of the Sun's distance, I was recently
examining Delambre's Solar Tables, which appeared in 1806,
and was astonished to find that they used the very same
value of the Sun's parallax (8"- 80) that is now used in the
Nautical Almanack. Encke's famous value, 8"- 5776,
announced some years later, was thus a change for the worse.
THE MEROPE NEBULA IN THE PLEIADES.—
Lowell Observatory Bulletin No. 55 contains an account of
the photography of the spectrum of the nebula ; an exposure
of twenty-one hours was given with the twenty-four inch
refractor, with the surprising result that the spectrum is con-
tinuous, with five distinct hydrogen lines and three fainter
helium ones, the spectrum being quite like that of Merope
itself. This was a great surprise, as the nebula resembles
that of Orion, and little doubt was felt that its spectrum
would be gaseous. Tests were made to see if diffused light
from Merope could have caused the continuous spectrum ; the
results appear to negative this idea. It is concluded that the
nebula shines by reflected light from Merope. It is calculated
that Merope would appear nearly as bright as our Full Moon
from the region of nebula photographed, and as we can photo-
graph a landscape by moonlight, the assumption of reflected
light seems reasonable. Mr. Slipher, the author of the
Bulletin, also suggests that the Andromeda nebula (for which
a similar spectrum has been found) may also shine by reflected
light, but this would only be possible if there were a very
bright central star, which is veiled from us by a dense screen
of dust or other opaque material. This seems a somewhat
strained hypothesis. We have, however, evidence of the
existence of such opaque screens in the numerous dark lanes
that are shown in photographs of the Milky Way. It would,
however, require an artificial and improbable arrangement that
the opaque veil should hide the central star from us, while
leaving it free to illuminate the nebula.
DISCOVERY OF A COMET IN SOUTH AUSTRALIA.
— Mr. Dodwell, the Director of the Adelaide Observatory, has
communicated the discovery of a faint comet by Mr. Lowe, at
'Laura, South Australia, at the end of December. Owing to
some delay in the announcement, and the vagueness of the
description, the comet was not seen elsewhere, and only a
very rough determination of the orbit is possible. I take the
opportunity of pointing out that should any readers of this
column pick up a comet, they can make observations of
sufficient accuracy to be of real value by carefully drawing
the small stars visible in the field of the telescope, and fixing
the position of the comet as accurately as possible by align-
ment among the stars, also noting the time when the position
of the comet was noted. A rough clue to the position must
also be given, which may be obtained by looking along the
outside of the telescope tube, and inserting the position on a
star map. Tracings of the sketches should be sent to some
Observatory, when the region can be identified with the aid of
a good star map or a photograph, and a very fair position of
the comet deduced. Had Mr. Lowe done this, we should
have known the orbit of his comet, and it would have been
possible to recover it at other observatories. I have myself
tested the possibilities of the method, and find that with care
it is not difficult to fix the place of a comet within 30" or 40".
OBITUARY. — The Council of the British Astronomical
Association has had another loss by death, that of Dr. David
Smart. He was an indefatigable cometary computer, and
gave invaluable assistance in the laborious work of carrying
back the motion of Halley's Comet for two thousand years,
and in discussing the extensive series of observations of its
recent return that were sent in from all parts of the world.
* Since there are 63,360 inches in a mile we have the curious relation exactly satisfied that on a scale of 1 inch for the distance
Earth-Sun a Light-Year is 1 mile.
179
180
KNOWLEDGE.
May, 1913.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
VEGETATION OF JAPAN.— Mr. H. Takeda gives, in the
February number of The New Phytologist, an extremely
interesting and readable account of the geography, climate,
and vegetation of Japan, which has well been termed the
" Britain of the East " — in fact, the author begins with the
almost inevitable comparison between the geographical
positions of Japan on the Asiatic coast and of Britain on that
of Europe. Apart from the geographical resemblance and the
existence of a warm current comparable with the Gulf Stream,
however, the climate and the vegetation show striking differ-
ences, as might, indeed, be expected.
The Japanese Empire consists, from north to south, of the
Kurile islands, the southern half of the Saghalien, Yezo, the
main island known to the Japanese as Honto, though by others
often called Nippon, Shikoku, Kyushu, the Loochoos, Formosa,
and the Pescadores ; these islands stretch diagonally from
52° to 21° N. Lat., and lie between 120° and 156° E. Long.
This area was in 1910 increased by the annexation of Corea,
hence the Empire has now about the same area (over two
hundred and fifty-six thousand square miles) as Austria-
Hungary, and the perflation (over sixty-three millions) is
nearly equal to that of Germany.
A warm current, the " Kuroshio," similar to the Gulf
Stream, arises between Luzon and Formosa, and flows along
the southern Loochoos to the southern end of Kyushu where
it divides into two ; the main stream bends northward and
flows along the south-east coast of Kyushu, Shikoku, and
Honto, while the smaller branch washes the west of Kyushu
and the Goto group and runs up to the Sea of Japan through
the strait of Tsushima or Krusenstern. The cold currents in
the North Pacific which affect the climate of Japan arise in
the Sea of Okhotsk and in the Behring Sea ; the most impor-
tant of these, the Kurile Stream, flows southwards along
Kamtschatka, turns towards the Kuriles and washes the
whole length of the island chain, and then runs chiefly along
the east coast of Yezo to 39° N. Lat., where the above-
mentioned main stream of the warm current bends away into
the Pacific Ocean ; the water of this Kurile Stream is very
cold, and even in summer its temperature does not rise above
5°C.
These warm and cold currents exert great influence on the
distribution of seaweeds ; this is clearly seen on the east
coast of Japan, the thirty-ninth degree being the separating
point of two different alga floras. On the west coast, however,
the course of the currents is more complicated, hence the
elements of different floras appear somewhat intermixed. The
strand flora is similarly affected, the northern elements being
distributed in the localities touched by the cold currents.
For instance, Mertensia maritima (with stouter stem and
larger flowers than the type in Europe and America) has a
wide distribution from the Behring Sea to 38° N. Lat. in
Okhotsk, Manchuria, North Corea, and Honto; Glaux mari-
tima., another arctic plant, is distributed mainly from Yezo
northward, but also occurs in a locality on the west coast of
Honto, whither it was probably carried by the cold currents ;
Plantago camtschatica is another plant found in localities
visited by these currents. As the warm current comes into
direct contact with the southern parts of Kyushu, Shikoku,
and Kii, various sub-tropical plants are found in these places —
Rhizophora mucronata, Senecio scandens, Ipomaea
pescaprae, Pteris Wallichiana, Asplenium Nidus, and so
on ; Statice japonica, mainly distributed in south-west Japan,
also occurs on the east coast as far north as 38° N. Lat.
The islands of Japan are all mountainous, some of the
smaller islands consisting simply of one or more volcanoes,
and most of the high mountains are densely clad with
luxuriant vegetation from foot to summit, often so densely
that the mountain forests are almost impenetrable. The
great chains in Central Japan, forming the backbone of Honto,
rise in places to three thousand five hundred metres ; there
are no glaciers, though traces of earlier glaciation have been
noted, but considerable neve is present on some of the
mountains. As the mountainous nature of the country would
suggest, Japan is naturally very rich in water ; a dense net-
work of rivers, torrents, and lakes is seen almost everywhere.
The rivers are usually short and their gradient steep, causing
frequent floods ; in late spring, when the snow begins to melt,
or when in summer the continuous rain carried by the south-
west monsoon falls in torrents, the mountain streams are
converted into raging floods.
Owing to the extension over thirty degrees of latitude and
the great variety in physiography, the climate is very varied ;
it is much influenced by that of the neighbouring countries
and modified by the warm and cold currents above mentioned.
The climate of the region from Formosa northward to the
mouth of the Amur River is controlled by the monsoons, formed
by the warm damp south wind in summer and the cold north
winds in winter ; the Loochoos, down to Formosa, are sub-
tropical and have practically no winter ; while the Kuriles,
south Saghalien, and parts of Yezo have the climate of Nova
Scotia or Iceland. In the winter drifting ice is carried by
currents and wind in the Kuriles and blocks up harbours from
November to April ; on the northernmost islands, not until
June does the snow disappear and vegetation awaken. The
rainfall is high (about one hundred and fifty centimetres a
year in Tokyo), especially in summer, when the air is very
damp, except in Yezo and the Kuriles which are not affected
by the monsoon ; the winter is dry and fine ; the annual
temperature range is considerable — in Tokyo the mean
temperature is 13°-8 C, maximum 36°-6, minimum 9°-2.
The vegetation is, naturally, well developed, varied and
abundant, with about four thousand five hundred cryptogamic
and six thousand phanerogamic species — apart from the floras
of South Saghalien (three hundred species of vascular plants
described) and Corea (two thousand two hundred species, of
which about two hundred are endemic). Though Japan is
surrounded by seas, in the west it is closely connected with
Manchuria through Corea, in the north it reaches Kamtschatka
by the Kurile islands, and Alaska through the Aleutian
islands, and it also has a connection with Amurland through
Saghalien ; on the other hand, the Loochoos and Formosa
join it to South China, the Philippines and the East Indian
islands. Hence, except on the eastern side, it is closely con-
nected with other countries, the floras of which show many
signs of close relationship with that of Japan, which was
probably connected with the mainland of Asia until a com-
paratively recent period. Plants indigenous in Eastern Asia
are also found in Japan, and teeth and bones of the mammoth
have been found in various parts of the country.
The main characters of the Japanese flora are (1) the
abundance of species and varieties, (2) the presence of
numerous endemic species, (3) the remarkably high proportion
of woody plants, (4) the presence of tropical and sub-tropical
plants throughout the country. Even in Yezo, the large
island of North Japan, are found many representatives of
southern floras (Picrasma, Vitex, Rhus, Hydrangea,
Aralia, Magnolia, and so on) growing together with
representatives of the cold flora ; in the northern parts of Honto
Aesculus, Zanthoxylon, Ardisia, Elaeagnus, Smilax, and
Camellia are often seen. The same or closely allied species
have been found in the Tertiary strata of the north of Eastern
Asia. Probably in the middle of the Tertiary period, even
Saghalien had a much warmer climate, for at that time
Ginkgo, Biota, and Sequoia grew there. When, towards the
close of the Tertiary, the greater part of the northern
Hemisphere was covered with ice, the main island of Japan
seems to have suffered very little. Probably since the end of
the glacial period and the change of climate in the middle
diluvial age, Japan has maintained a fairly warm temperature
enabling many plants of warmer climates to survive, while in
Saghalien the temperature has been very low so that this
island is unfavourable to plants of the warm temperate region.
The arctic plants once compelled by the cold climate of the
glacial period to come southward were consequently left
behind when the climate became warmer, but only persist on
the summits of the high mountains.
Starting with the flora established in the Tertiary period, the
migration of arctic plants towards the south and of tropical
May, 1913.
KNOWLEDGE.
181
plants towards the north has caused the present flora to be
very complex. The connection of the country with the
northern, north-eastern, south-eastern, and southern parts of
the Asiatic continent made paths for arctic and tropical plants
into Japan ; the interruptions between the various islands are
bridged over to some extent by currents and wind. Evergreen
trees and shrubs and many other tropical plants found their
way northwards and became acclimatised to the colder winter
night and contented with comparatively high temperature
during the day, and above all the warm and moist atmosphere
during the summer ; while those coming from the north or
north-west, where they were accustomed to a severe winter,
migrated up the mountains until they obtained the necessary
climatic conditions. Investigations of the Tertiary fossil plants
of Japan, Amurland, and North America, show that the
present flora originated in the large common flora of the
northern region of the Far East. One striking feature is that
the flora of the north-east part of Japan bears a striking
relationship to that of the Atlantic coast of North America.
This was noticed by Asa Gray, who compared the two floras
and showed that more than sixty per cent, of Japanese plants
grew on the eastern coast of North America, or were
represented by closely-related species, while only thirty-seven
per cent, grow on the western coast. His suggestion that the
close affinity between these floras originated in the Tertiary
period has been borne out by further geological evidence, and
Engler and other phytogeographers have concluded that the
two regions were actually connected, and had a similar
climate and flora. After the glacial period many plants
which migrated towards the south returned northwards and
formed the foundation of the present flora of Japan, while in
North America a change in climate had taken place between
that of east and west — in the west the climate became dry and
mild, and caused great alteration in the flora, in the east little
change has taken place and many old species have been
preserved.
Apart from the northern islands, however, the vegetation
of Japan shows little actual resemblance to that of North
America. Although the same or closely allied plants occur in
both regions, they are not found in the same proportion. For
instance, in Japan, Tsuga forms continuous and almost
unbroken forests of great extent on the mountain slopes, above
one thousand six hundred metres from sea level, while in
North America this tree is rarely found except scattered in
small groves, or as individuals in the deciduous forests ; on
the other hand, Picea and Abies, which, in America, form
immense forests almost to the exclusion of other species, in
Central Japan grow singly or in small groves on the lower
border of Tsuga forests, or mingled with broad-leaved trees.
In northern Japan and on the high mountains of Honto,
birches are more abundant than they are in the northern
forests of America, and the river banks in the north, like
those of North Europe and Siberia, are lined with arborescent
willows and alders, which are rare in eastern North America,
where these genera are usually represented by trees. More-
over, the numbers given in Gray's estimate should be reduced
slightly, since he included as natives some Chinese and Corean
plants cultivated in Japan. Besides these and some endemic
species, the flora of Japan includes many plants of the boreal
region of the old world. For instance, Asperula odorata,
which occurs in Europe but not in America, is abundant in
North Japan. In South Japan, many tropical and sub-tropical
elements may be seen ; certain plants growing in the central
and southern parts of the country have also a close affinity to
those of South China, as well as to those of the Himalayas.
The vegetation of Japan may conveniently be arranged in
three divisions mainly based on the climatic conditions — (1)
Northern Region, extending from 38° N. Lat. northwards to
the Kuriles and Saghalien ; with the northern part of Corea ;
(2) Middle Region, including the greater part of Honto and
Shikoku, part of the north of Kyushu, and South Corea ; (3)
Southern Region, including the southern parts of Kii and
Shikoku, the greater part of Kyushu, the Bonin islands, the
Loochoos, Formosa, and the Pescadores. Within each of
these regions the northern and southern portions show certain
differences in the vegetation. The northern part of the
Northern Region is represented by the arctic, and the southern
part by the sub-arctic, with a few elements of the cold
temperate flora ; in the northern part of the Middle Region
the plants of the cold temperate flora are found, in its
southern part those of the warm temperate ; the Southern
Region has warm temperate and sub-tropical plants in its
northern part, and tropical plants in the southern.
(1) Northern Region. — The sea coasts are lined partly with
sand-dunes and partly with cliffs ; salt marshes are but
poorly developed. Lists are given for these formations ; the
exposed parts of the cliffs show many interesting arctic species
of Androsace, Artemisia, Draba, Empetrum, Erigerou,
Salix, Saxifraga, Sedum, and so on. Lists are also given
for the dry hillsides, humid places in the mountain valleys,
the Sphagnum bogs (not much in evidence in the other
regions, but here fairly well developed), the ponds and lakes,
and the forests. The characteristic forest trees are deciduous
oaks, birches, cherries, elm, hornbeam, maples, poplars,
Cercidiphyllum (a peculiar tree, the sole representative of
the family Cercidiphyllaceae, and closely resembling Ginkgo
in general appearance), and various willows in damp places;
conifers are represented by a few species of Abies, Juuiperus,
Larix, Picea, Taxus and Thujopsis, pines being rare — the
only wild species is the small P. putnila, usually on mountain
summits. Even in Saghalien and the Kuriles there are
various woody climbers (species of Celastrus, Hydrangea,
Rhus, Vitis, and so on), growing in tropical luxuriance — the
abundance of these plants in Japan has been attributed to the
undergrowth of bamboos which cuts off the light and makes
the plants climb up the trunks of other trees. On the high
peaks, not much over two thousand three hundred metres,
there are interesting arctic plants like Bryanthus and
Pliyllodoce, generally on exposed rocks.
(2) Middle Region. — This region is very extensive and
mountainous, hence the vegetation is varied. The coasts are
lined by pines (Pinus thunbergii and so on) and many dune
plants : rocky cliffs are infrequent, and show a poorer vegeta-
tion than in the Northern Region. The forest trees show
great variety ; evergreens occur largely, and broad-leaved
species are especially numerous; there are many conspicuous
spring-flowering species of Azalea, Prunus, Pyrus, and so
on. More species of Pinus appear in this region, and Crypto-
rneria flourishes here, while the tall bamboos (mostly species
of Pliyllostachys) form a special feature of the vegetation,
being mostly under cultivation and forming dense groves.
This region contains the great mountain ranges with
perpetual snow in the gulleys, and their flora shows
ascending zones of vegetation — illustrated by reference to
Fujiyama, the highest volcano in Japan. The gently sloping
basal zone, up to three thousand feet, consists of lava and
cinders, and is largely covered with grasses, brambles, roses,
and bracken, with numerous herbaceous phanerogams, and in
places various trees ; this passes into the tree zone, divided
into a lower belt with deciduous trees (maples, alders, birches,
hornbeam, oak, and so on) and many shade-loving plants in the
undergrowth, and a higher conifer belt in which Abies firma
appears first, and is followed by Larix, Picea, Tsuga, and so
on. Above two thousand metres, the gradient becomes
steeper, and trees are less abundant, the approach to the
shrub zone being marked by rowan, rhododendron, alders,
stunted birches, shrubby Spiraea, dwarf willows, and various
Ericaceous shrubs, with herbaceous species of mostly alpine
character. The zone from seven thousand five hundred to
ten thousand feet belongs to the alpine region, with typically
alpine and arctic plants ; above this to the summit (about
thirteen thousand five hundred feet) is the lichen zone with
Cetraria islandica, Cladonia rangiferina, Rhizocarpon
geographicum, and so on. The alpine zone of Fujiyama
does not contain many plants, though a few are known only
from this mountain, but on the other mountains of Central
Japan, which form the backbone of the main island, and are
often called the Japanese Alps, alpine vegetation is well
developed. On these mountains a creeping pine (P.pumila),
also found in Siberia, appears in the shrub zone and extends
to the alpine zone ; many interesting plants are found in the
shade of the thickets of this pine. Many arctic plants found
182
KNOWLEDGE.
May, 1913.
on the rocky cliffs of the Kuriles occur also in the alpine zone
of these mountains.
The aquatic vegetation of the Middle Region shows great
diversity ; the genera, and many of the species are cosmo-
politan ; Isoetes japonica, one of the largest species of this
genus, frequently grows in running water instead of still lakes.
(3) Southern Region. — Even at the northern limit of this
region, in Kyushu, the vegetation is quite sub-tropical. On the
coasts, washed by the warm current, various Indo- Malayan strand
plants are found; in the Loochoos, Bruguiera gymnove-
rhiza forms the mangrove forest in the tidal estuaries ; well-
developed mangroves are seen in Formosa, consisting of
Avicennia officinalis, Kandclia, Rhizophora, and so on.
Various palms belonging to the genera Arenga, Livingstonia,
Trachycarpus, and so on, nourish in this region, which may
be characterised as a region of Fiats, with which broad-leaved
evergreen trees and shrubs, such as various Lauraceae, Ouerciis,
Hibiscus, Myrica, and so on, are found. On their branches
are many epiphytic lycopods and ferns, and sometimes par-
asites (Loranthus and Viscum) are found, while in the dense,
moist forests there flourish many tropical ferns.
In Formosa also the vegetation is typically tropical, with
abundance of huge trees, thick bushes, dense forests with
numerous woody climbers, and so on. In the mountain valleys
the camphor tree (Cinnamomum camphora) reaches great
dimensions; Macuna gigantea and Pusaetha scandens
(leguminous trees with enormous pods), other climbers, and
gigantic bamboos, tall tree-ferns, palms and Musa grow in the
forests and on mountain slopes ; while higher up on the moun-
tainswhichoccupythegreaterpartof the island, conifers are seen
at an elevation of two thousand metres. Chamaecyparis
formoscnsis. Cunninghamia, Konisliii, Picea morrisoni-
cola, and Pinus formosana are some of the interesting
trees, and are only known from this island, while a few years
ago a new conifer discovered here was placed in a new
genus (Taiwania cryptomerioides) ; and higher up we get
first the shrub zone, and then, at four thousand metres and
upwards, various alpine and arctic species of Arabis,
Artemisia, Cer ostium, Descliampsia, Festuca, Fragaria,
Gentiana, Luzula, Potentilla, Sibbaldia, and so on. The
flora of Formosa has some two thousand five hundred species
of vascular plants, seventeen per cent, of which are endemic,
and doubtless many more remain to be discovered.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon.), F.I.C.
UTILISATION OF MILK WEED.— The current issue of
the Journal of the Society of Chemical Industry (1913,
XXXII, 72) contains a paper by Dr. A. C. Neish, describing
experiments that have been made to discover uses for the
enormous quantities of this wild plant which are annually
wasted. The common milk weed (Asclepias syriaca) grows
abundantly on sandy or clay soil in the United States and
Canada. It produces a milky juice or latex, which yields from
two to three per cent, of rubber, but the amount is so small
and its quality so poor that its extraction would not be
commercially profitable.
On the other hand the bast fibres of the plant are likely to
prove a more profitable product, for they can be readily
separated, and when bleached yield a white silky textile
material, which is stronger than flax, which in other respects
it closely resembles. The seeds also contain about twenty-one
per cent, of a drying oil which may be easily extracted with a
suitable solvent, while the down attached to the seeds is white,
very soft and springy and contains 0-9 per cent, of ash. It
could be utilised as an upholstering material, as has already
been done with the seed hairs of other species of Asclepias.
The woody tissue, about eighty per cent, of the plant material,
yielded, on treatment with soda solution under pressure, a
pulp from which paper of good quality could be made. From
the results of his experiments in general Dr. Neish considers
that it may prove practicable to start a new industry to
utilise the product of the common milk weed and similar
plants of the same species, but some system of cultivation
would probably be required to supplement the supply of the
wild plants already available. Such a crop might be grown
upon dry or wet soils with which little else could be done.
USE OF ALCOHOL AS A MOTOR FUEL.— The
"Times Engineering Supplement " for January 15th, 1913,
deals with the question of the substitution of alcohol for petrol
as a motor fuel. A comparison of the relative calorific values
of the two liquids showed that petrol of specific gravity 0-684
produced eleven thousand six hundred and twenty-four
calories per kilometre, while methylated spirit gave only six
thousand two hundred calories. In practice, however, this
superiority of petrol disappears. For example, in comparative
tests with the two fuels in specially constructed eight horse
power engines, it was found that 340 grammes of petrol were
consumed per horse power hour as against 373-5 grammes of
methylated spirit, showing that the relative efficiences were as
16-5 per cent, for the petrol and 28 per cent, for the alcohol.
The better results given by the alcohol are to be attributed to
the greater ease with which it is possible to obtain complete
combustion, and to the smaller proportion of air required.
In addition to these factors, it is possible with the use of
alcohol to obtain greater compression and a cooler cycle, both
of which conditions tend to economize fuel.
Although denatured alcohol can be obtained free of duty,
its price is still as high as that of petrol at the present time,
and the reason for this is not the manufacturing cost, but the
charges made by the Government for supervision to ensure
that the spirit is not drinkable when it leaves the distillery.
A spirit containing about ten per cent, of crude benzene would
be undrinkable, and could be manufactured at a cost of about
sixpence per gallon, while only slight modifications of the
carburettor would be required to enable it to be used in
ordinary petrol motors. Hitherto efforts have been directed
to the perfection of the petrol engine, and it is possible that
when an equal amount of research has been given to discover
the best methods of using alcohol, the latter will be recognised
as the more suitable fuel.
UTILISATION OF HORSE-CHESTNUTS.— Although
several attempts have been made during the last two centuries
to utilise the horse-chestnut in the preparation of detergent
preparations, none of them have been adopted as commercial
processes. As far back as the year 1757 it was discovered by
a Frenchman named Marcandier that the juices of this nut
had strong frothing and cleansing properties, and that they
could be used instead of soap for removing dirt and grease
from textile materials. . A similar use of horse-chestnuts was
known in Germany, as is shown by the account given in 1824
in a technical paper.
After the lapse of years, the idea of using horse-chestnuts
for washing preparations has again come to the fore, and since
the year 1888 there have been several processes patented for
extracting the saponine or frothing substance from the nut. An
outline of the methods suggested, and a discussion on profitably
utilising the other constituents of the horse-chestnut, is given
by M. Rousset in the current issue of Les Matieres Grasses,
1913, VI, p. 2980.
The kernel, after removal of the shell (which is rich in
tannin, and is utilised in the preparation of a tanning extract
for leather), contains the following proportion of extractive
substances: — Oil, 6-6: aesculic . acid, 3-2; carbohydrates,
10-8; reducing sugars, 5-2; gums, 1-2; and proteins, 1 • 0
per cent.
The oil, which can be extracted with petroleum spirit, is
a pale yellow liquid with characteristics similar to those of
almond oil. After removal of the oil, the residue, when
extracted with dilute alcohol, yields an extract containing
about fifteen per cent, of aesculic acid, a substance of a
saponine character which has strong lathering and cleansing
properties.
Finally, the mass left from the two extractions could be
used in the preparation of a white starch, which, after treat-
ment with cold water to remove a bitter principle, would be
quite suitable for use as a food,
May, 1913.
KNOWLEDGE.
183
GEOLOGY.
By G. VV. Tyrrell, A.R.C.Sc, F.G.S.
LONDON WELLS. — The water-supply of London is of
such tremendous importance that contributions to its fuller
study are extremely desirable. Hence the Geological Survey
has accomplished a valuable piece of work in compiling an
exhaustive record of London wells. The information as to
this mode of water-supply is scattered, and in the older
records incomplete. So far as is possible this incompleteness
has been remedied, and a very large number of borings made
during the last few years have been included in the Memoir,
which has been compiled by G. Barrow and L. J. Wills. The
introduction by Mr. Barrow is a valuable account of London
water-supply, and describes the strata penetrated by the wells,
methods of well-sinking, relation of water-supply to geological
structure, and many other kindred subjects of interest. Part
II consists of a catalogue of published London wells, and
Part III of a descriptive list of new London wells with some
old ones.
Special attention is drawn in the introduction to the
continued fall in the water-level under London. The fall is
greater than was anticipated, and has recently been taking
place at an increased rate. The fall is illustrated by contour-
maps of the water-level at different dates in the London area.
These show very clearly the setting up of specially low water-
levels, and the gradual outward spread of the low contours
from these areas. The fall may be illustrated by the three
wells sunk in 1847 to supply the fountains at Trafalgar Square.
These once produced five hundred and eighty thousand
gallons a day, and supplied several government offices beside
the fountains. Only one is now in use, and supplies only
eight thousand gallons an hour, and in this well the water-level
has fallen one hundred and fifteen feet in sixty-four years,
A similar instance is offered by the deep well sunk in 1864 to
supply the fountains at the head of the Serpentine in Kensington
Gardens. There is a general coincidence of the areas of low
water-level with those areas where there is a considerable
thickness of Tertiary beds, or where the top of the Chalk is a
considerable depth below the surface. A great thickness of
cover tends to check the rate of inflow of the water from the
chalk outcrops, and this, added to the lowering of the water-
level by pumping, has produced especially heavy falls in
certain areas. Moreover, the Chalk, so often thought extremely
permeable, is only so under pressure ; and if the head of
water in the formations above the Chalk be reduced, as, for
example, by the fall in the water level, the passage of water
through the Chalk becomes increasingly difficult. The low
water-level extends much farther to the north of the Thames
than the south. This appears to be due to three main causes.
There is a much thicker and more extensive cover of imperme-
able strata (London Clay) in the north than in the south.
This not only prevents rain-water from entering the Chalk,
but also tends, by reason of its weight, to hinder the flow of
water from the north towards the central areas. Then, again,
the intake areas of Chalk are more distant on the north than
on the south. Furthermore, the existence of the deep valleys
of the Lea and Colne transverse to the general direction of
underground water flow towards London, still further depletes
the supply on the north as compared with the south. In the
latter, not only are the intake areas nearer, but they are not
traversed by valleys in which part of the flow towards London
might be abstracted by springs.
IGNEOUS QUARTZ.— The theory of the probable direct
igneous origin of some quartz veins and masses receives
support from observations made by Dr. J. Ball in South-
Eastern Egypt. According to the memoir, " Geography and
Geology of South-Eastern Egypt" (1912), this area, covering
twenty-two thousand square miles, consists principally of
ancient metamorphic and igneous rocks, with a few patches
of Nubian sandstone (Cretaceous), and gypseous limestone
(Miocene?). The igneous rocks include great masses of
granite and serpentine, with subordinate syenite, diorite,
and gabbro. In addition several masses of quartz-rock of
igneous origin have been found. The most conspicuous of
these occurs as a group of three hills known as Marwot
Elemikan (Marwa = Arabic for quartz). They consist
almost entirely of white quartz, and from their dazzling white
colour form landmarks visible at a great distance. The only
other mineral present is white mica, of which a few spangles
occur in the outer portion of the mass. These three bosses,
together with another on the south side of the Wadi Khoda,
penetrate granite.
Of quartz veins and dykes the best-known example in
south-eastern Egypt is a great dyke forming the backbone of
a ridge known as Erf el Fahid. This dyke is intrusive in
schists, is at least ten metres wide, and can be traced for two
kilometres. A similar dyke occurs in the ridges to the south-
west of Erf el Fahid.
Dr. Ball considers that the shape of these masses of quartz,
their close association with aplites and pegmatites in at least
one locality, the absence of ores and of minerals due to
deposition from solution and the occasional presence of mica,
all point to igneous origin. He considers them as the final
ultra-acid products of the differentiation of a granitic magma.
MICROSCOPY.
By F.R.M.S.
QUEKETT MICROSCOPICAL CLUB. — March 25th,
Mr. G. T. Harris presented a type collection, numbering
seventy-two preparations, of British Hydrozoa.
Messrs. Heron-Allen and Earland read a paper " On some
Foraminifera from the southern area of the North Sea,
dredged by the Fisheries cruiser ' Huxley'." The work was
undertaken with the view of determining the distribution of
Saccammina sphaerica Sars. and Psammosphaera fusca
Schulze, in the area mentioned. Material was examined
from three stations far to the north-east of the Dogger Bank
near the Great Fisher Bank, and from three stations in the
belt of deep water lying to the west of the Dogger, close in to
the Northumberland coast. The first-named species was
found to occur only at two of the inshore stations, but the
second species was found in all the dredgings except that from
one of the inshore stations. The authors' first intention was
to examine the material solely with regard to the presence or
absence of these two species, but so many other species were
noticed that an exhaustive list was prepared containing one
hundred and thirty-seven species, many of which are first
records for this area, and were given in detail in a table
appended to the paper. A number of excellent lantern slides
from photomicrographs of some of the more interesting forms
was shown.
Mr. D. Bryce read a paper on " Five new species of
Bdelloid Rotifers." Four belonged to the genus Habrotrocha
and the fifth to Callidina. They are fully described and
figured in the current (April) issue of the Club's Journal.
THE MECHANICAL CONSTRUCTION OF THE
MICROSCOPE. — Although the optical parts of the microscope
have been greatly improved in recent years, the mechanical
construction of the instrument has not advanced in proportion.
The books written on the subject, which have come under
the writer's notice, have little to say on general construction,
but confine themselves to descriptions of the models by-
various makers.
The principal faults, in the writer's opinion, are that most
microscope stands are built on too small a scale and that
there is an unnecessary amount of patchwork in the
assembling of the various parts. For some purposes a
portable instrument is no doubt desirable, but for general
work ample room for manipulation, for the use of low power
objectives, and various accessories, is a most important
feature.
The optical equipment of the microscope need not here be
described in detail ; it is sufficient to point out that it consists
of two divisions, namely, the upper or magnifying portion,
consisting of the ocular and objective, and the lower or
illuminating portion, consisting of the condenser, and mirror,
184
KNOWLEDGE.
May, 1913.
Plan
or source of light ; between these must be fixed the
stage for carrying the object under examination.
The Stand of the microscope consists generally
of two parts, the foot or base which supports the
instrument, and the limb which is connected to the
upper part of the foot through an inclining joint
permitting any angle of inclination from the vertical
to horizontal.
Much discussion has taken place concerning the
relative merits of the two styles of base generally in
use, namely, the tripod or so-called English style,
and the horseshoe or so-called Continental style ;
the former, no doubt, gives greater stability to the
instrument in various positions, and the latter provides
more room for the manipulation of the
substage fittings, especially if these are
required to be swung out from the optical
axis. A little consideration will shew how
these advantages can be combined in a
suitable design.
The Limb should be one continuous
piece to which all other parts can be
attached either rigidly or through slides
which allow for the requisite vertical move-
ment. The limb should provide ample room
between the top slides carrying the body
tube and the stage, so that a low power
objective (with a working distance of, say,
three inches) can be used when a nosepiece,
or objective changer, has been added to
the tube.
At the present time other appliances are
supplied for attachment to the body, such
as a slot for quartz wedge, a vertical
illuminator, and so on, for which the space
provided is generally quite inadequate ;
some modern objectives also are of much
greater length than those formerly con-
structed.
In my opinion the construction
should allow sufficient room for the
use of any accessories necessary
with a low power objective when a
mechanical stage has been added
to the stage proper ; if these acces-
sories are not used, and an excep-
tionally short objective with small
working distance could not be racked
down far enough for focusing, a
matching piece could be used on the
body tube.
The space between the limb and
the optical centre could be made
with advantage greater than usual ;
it should be such as to allow for
a large- sized stage, say five inches
in diameter, to be completely rotated
with a mechanical stage attached,
and to allow the limb to be used
as a handle for lifting the instru-
ment without any strain or derange-
ment of the various adjustments.
The stage is preferably carried on
a stage bracket ; this construction
allows for a wide choice of the style
of stage and also provides for a
slight adjustment to insure the stage
being exactly at right angles to the
optical axis.
Another point which has been
much discussed is the construction
of the fine adjustment ; in the first
place, the coarse adjustment should
be made and finished so that it
works as smoothly as possible with-
out any sign of backlash in the
Figure 179.
Section through
body.
Figure 180.
A>ith stage removed.
I.I.I
J
Figure 181.
Side elevation. Key to Figures 179, 180 and 181
A. Stand ; B. Limb ; C. Stage; D. Body ; E. Sub
stage; F. Tail-piece; G. Fine adjustment.
movement or looseness in the slide ; if this is done
the fine adjustment need only be used for high powers
and need only have a small amount of vertical move-
ment (say one-sixteenth inch).
The fine adjustment mechanism should be as
compact as possible and should act directly upon
the slide carrying the coarse adjustment ; there is no
doubt that mechanically the method involving leverage,
by which a greater movement is provided and less
weight comes upon the fine adjustment screw, is
preferable and more sensitive than that in which the
whole weight of the body is borne directly on this
screw, and it is difficult to see why the latter method
should have ever been adopted.
In most models the under-stage fittings
consist of a general patchwork attached
indiscriminately to the stage or limb.
They should be connected directly to the
same limb which carries the stage and
the body tube which then forms a con-
tinuous support for the optical parts above
and below the stage.
Sufficient room should be provided below
the stage for a modern condenser, with a
stop carrier and iris diaphragm, below
which can be placed a large sized polar-
ising prism, sufficient room also for the
requisite vertical movement for focusing
and dismounting of the various parts con-
veniently without interfering with the
mirror which is also attached to the rim
through the tailpiece. It is also advisable
that the substage fittings can be swung out
from the optical centre.
The line drawings (see Figures 179-
181) shew a simple design which
complies with the requirements noted
above.
The photograph (see Figure 182)
illustrates a more complete model
which was entirely designed and
constructed by the writer. The chief
differences from the design shewn in
Figure 181 are that the stand is
somewhat higher, the stage has a
vertical movement of one inch and
that a separate holder is provided
for a polariser below the condenser.
A short description of this instru-
ment is as follows: —
The stand consists of two parts —
the base and the upright. The base
is supported on three feet shod
with cork, and having a spread of
seven inches by eight inches. The
upright part has two sides one inch
apart, between which the limb is
suspended on a pin at the top, and
can be inclined at any angle from
the vertical to the horizontal, a
second pin at the back supporting the
limb in the latter position. The
upright and horizontal parts of the
stand are connected by screws, and
can be taken apart when desired
to pack the instrument into a small
bulk. The limb is cast in one piece,
provided at the top with a dovetail
slide to carry the body, and at the
bottom with a slide to carry the
stage bracket and substage fittings.
The central portion of the limb is of
I section, to secure rigidity without
undue weight. The fine adjustment
is located at the top end of the limb
in a hollow recess ; it is actuated by a
Inches .
May, 1913.
KNOWLEDGE.
185
divided screw head projecting backwards, which works on the
long arm of a " bell crank " lever, on the bottom or horizontal
arm of which rests the fine adjustment slide. The reaction is
taken up by a vertical spiral spring. The pitch of the screw
thread is forty to the inch. The vertical arm of the lever is
four times the horizontal. A complete revolution of the fine
adjustment screw gives, therefore, a movement to the body of
,•00625 inches.
The bearing surface of the fine adjustment slide is two and
a half inches in length, and the possible movement about one
eighth of an inch.
The body is carried on a slide having a bearing surface of
three and a half inches in length, actuated by the coarse
adjustment pinion, with a movement of three inches. The
main tube is one and five-eighths inches in diameter, and con-
tains two draw tubes giving a latitude
of extension of from one hundred
and sixty to two hundred and sixty
millimetres.
In the body tube, as close to the
back of the objective as possible,
are — first: an iris diaphragm ; second:
a slot which can be uncovered or
closed by a circular ring, and third : a
slide carrying an analyser prism, Mb^l
which can be moved in and out of wj
the optic axis as desired. The two
latter accessories, in conjunction with
a polarising prism below the stage,
are indispensable for petrological
work. The advantage of placing the
analyser near the objective instead
of over the eyepiece — as is some-
times done — is that a much larger
field of view is obtained with a small
prism. The bottom of the inner
draw tube is screwed to receive a
" Bertrand Lens." Very perfect
interference figures in crystals have
been obtained with this instrument.
At the bottom of the body is an
objective changer, which is preferred
to the usual nosepiece ; this is
considered as a fixture and is taken
into account when measuring the
tube length.
A circular stage — five inches in
diameter — rests upon a stage bracket.
It is provided with centreing screws
and divided in degrees reading
from a fixed index. Upon the
circular stage are two slides in which a mechanical portion
is held, having a rectangular movement of two and a quarter
inches from left to right and one and a quarter inches at right
angles. The stage can be completely revolved with the
mechanical portion in any position. The stage bracket is
connected to the bottom of the limb through a slide actuated
by rack and pinion, by which the stage can be moved in a
vertical direction with regard to the limb a distance of one
inch. The bearing surface of this slide is two and a half
inches in length and can be fixed by a binding screw in any
position. This movement of the stage adapts the instrument
to metallurgical work, and also allows for a variation of the
gap between the stage and body.
The substage fitting is carried on a slide, actuated by rack
and pinion, having a vertical movement of two inches with
regard to the stage. It is provided with two carriers : the
upper provided with centreing screws to hold the condenser ;
and the lower to hold a polarising prism. These carriers are
supported on a vertical pin, upon which they can be separately
swung clear of the optic axis without dismounting — they are
provided with clamps to hold them in the central position.
The tail-piece to carry the mirror is attached to the limb,
and is of the ordinary tubular type, which allows a mirror
two and a quarter inches in diameter to be placed in any
Figure 182.
Complete microscope,
structed by
necessary position or to be swung out of the centre when
using the instrument in an horizontal position.
General : All the sliding parts of the instrument were
designed to give ample bearing surface for the weight
supported, and are all provided with means of adjustment
and for taking up any slackness due to wear.
The principal parts were cast in phosphor bronze and the
smaller parts, bearing strips, and so on, were made of good
quality brass.
The optical parts and some accessories were supplied by
Messrs. Watson & Son, as follows : — Objectives and oculars,
" Holoscopic " series ; substage condenser, " The Universal " ;
polarising and analysing prisms; objective changer, " Facility."
The total height of the instrument, racked down, without
eyepiece, is fifteen inches. The weight, in working order,
= 17 lbs.
The instrument can be easily dis-
connected into three parts. The limb
with all attachments can be lifted
from the stand by the withdrawal of
connecting pin in the inclining joint.
To prevent accident, the stand at this
joint is provided with semi-circular
cheek pieces, which support the limb
when the pin is withdrawn. The
stand can then be taken into two
parts — the vertical and horizontal —
which are connected by quarter inch
screws. When thus disconnected,
the instrument can be packed into
a case twelve and a quarter inches
by nine inches by five and a quarter
inches inside measurements.
George G. Holmes, A.R.S.M
PHOTOGRAPHY.
By Edgar Senior.
CRYSTALS AND X-RAYS— Of
the endless number of instances in
which photography has come to the
aid of the original investigator, none
perhaps are of greater interest and
value than the one which has recently
led to the discovery of the inter-
ference effects obtained with X-rays,
by means of crystals. Ever since
Rontgen rays were first discovered
in 1895, attempts have been
made to obtain results analogous
to interference, diffraction and reflection of ordinary light
waves, but always until recently with negative results. The
wave lengths of light visible to our eyes are those which are
comprised between 7594 (red) and 3930 (violet), and beyond
the violet are those of shorter length, known as ultra-violet,
to which photographic plates are particularly sensitive. Now,
it has always been supposed that X-rays were of the
nature of ultra-violet light of extremely short wave length,
quite beyond the limits of the spectrum known to us. The
experiments, however, carried out by Messrs. Friedrich and
Knipping at the instance of Professor Laue, opens up a
new range of the spectrum which was unexplored before.
In conducting any experiments by means of the spectrum
of visible light, a diffraction grating is very commonly
used in order to decompose the light into its constituents,
from which the wave lengths can be measured. A
diffraction grating is usually a plate of glass having a
number of fine lines ruled upon it at regular intervals, the
lines being practically opaque, acting as so many diffracting
objects, while the clear spaces between allow of free trans-
mission of the light. The spectra produced by means of
gratings are known as interference spectra. Now, as it was
supposed that X-rays consisted of waves of very short length,
Professor Laue formed the conclusion that it might be
Designed and con
the writer.
186
KNOWLEDGE.
May, 1913.
possible to obtain interference effects with them, by using a
crystal as a diffraction grating. As the atoms of a crystal are
arranged regularly, and the spaces between them have about
the same relation to the supposed wave length of the rays as
the " constant " of a diffraction grating has to that of visible
light, a crystal would thus form a most perfectly ruled grating
for them. In order to test this practically the aid of photo-
graphy was called in. In the first place, however, it was
necessary to obtain as far as possible a parallel beam of
X-rays, so that the conditions should be the same as
when a parallel beam of light is allowed to fall upon
the grating of a spectroscope. This was accomplished
'as well as could be," by means of holes pierced in sheets of
lead, the X-rays being finally transmitted by an aperture
of one millimetre in diameter, and thus a very narrow pencil
was obtained. This was allowed to fall upon the crystal, and
behind it, at a distance of about three centimetres, a photo-
graphic dry plate was placed perpendicular to the beam of
rays. The rays, after traversing the crystal, fell upon the
plate, and this, after the necessary exposure (which amounted
in some instances to several hours), was developed. The
effect produced was shown as a dark, circular spot, surrounded
by a series of much weaker ones, arranged in regular order.
By altering the distance of the photographic plate from the
crystal, the spots could be made to approach, or recede from,
the central one, so that it appeared clear that they were due
to narrow rectilinear pencils spreading outwards from the
crystal. It was found that the angles some of these made
with the undeviated rays were as much as forty degrees. It
was also noticed that the spots scarcely altered in size as the
distance between the plate and the crystal was increased, but
remained of the size of the smallest aperture employed for the
transmission of the rays. And whatever the final result of
the experiments may lead to, whether they solve the problem
of crystal structure as well as that of the true nature of
X-rays, there is no doubt but that photography has again
rendered great service in showing that which otherwise
might have remained of theoretical interest alone.
FIXED FOCUS CAMERAS.— Fixed focus is the term
applied to hand cameras in which the plate is placed at a
fixed distance from the lens, so that no focusing of the image
can be accomplished. In many cases the plate is at a distance
greater than the focal length of the lens ; in other cases it is
at the focal length itself. Now, in order for an image to
appear sharp, it is generally considered that any point in the
image of an object must not exceed one hundredth of an inch
in diameter. Therefore, the distance of the object must be
such that these points, " termed discs of confusion," do not
exceed this value in the image. When the plate is at a
distance from the lens greater than its focus, then a slight
amount of confusion exists for objects at infinity. If, however,
the plate is placed at a distance from the lens equal to its
focal length, then all objects from a certain near point to
infinity are in sharp focus. In order to find this point the
following formula is employed : — — — where / = the
a
the focal length of the lens, and a the value of the stop. Thus,
suppose with a lens of five inches focus and stop F/6 it is
desired to find the nearest point beyond which everything else
would be in focus, then = 34-7 feet.
12 X 6
Therefore, all objects from this distance to infinity would be
sharply focused : that is, the circles or discs of confusion
forming the points in the image of the objects would not be
greater than one hundredth of an inch in diameter with the
stop employed. When the object is nearer than this, then the
image will be at a greater distance, and will agree with
the case first stated, and although there may be certain
advantages attending it, the method given for calculating that
of the object would no longer be correct, as the formula only
holds good when the plate occupies the position of the
principal focal plane of the lens. There are, doubtless, many
cases in which strict attention to theoretical details need not
be paid, this, of course, depending largely upon individual
ideas ; but it should always be remembered that when images
are intended for enlargement either by means of lantern
slides or otherwise, the results are likely to suffer in a serious
manner if too little attention be given to obtain a sufficiently
sharp image in the first place.
PHYSICS.
By Alfred C. G. Egerton, B.Sc.
RONTGEN RADIATION.— When the cathode rays— the
rays emitted in a vacuum tube normally to the cathode — were
originally discovered, some considered them to consist of
small discrete particles, and others considered them to be
waves in the ether. Professor Sir J. Thomson's researches
eventually proved without doubt that the rays consisted of
negative charges emitted with great velocity carried by
corpuscles of mass, one seventeen-hundredth of the mass
of the atom of hydrogen. The cathode ra5's, when they
impinge on a substance, are stopped, provided the thickness
of the substance is sufficient, and they give rise to another
penetrating type of radiation called the Rontgen rays, after
their discoverer. The rays evolved are rays of mixed
penetrating power, but for every metal there is also a
definite radiation, characteristic of that metal and of definite
penetrating power; the higher the atomic weight of the
element, the greater the penetrating power of the charac-
teristic radiation. Now, the Rontgen or X-rays give rise to
secondary rays on being allowed to impinge on a metal, and
these rays, too, are found to be characteristic of the metal,
their velocity varying with the atomic weight of the metal.
Thus, a cathode ray gives rise to an X-ray, and an X-ray to a
secondary ray of the same type as the cathode rays. The
7 -radiation from the radio-active substances is also in all its
properties similar to a very penetrating Rontgen radiation.
Now, discrete electrically-charged particles, be they positive
or negative, are affected and bent out of their path by magnetic
or electric fields, but the X-rays or T-rays are not affected by
such fields. Consequently, the rays must be either neutral
and consist of a pair of equal and opposite electrical charges,
or consist of a pulse (a kind of single wave) in the ether. It
cannot be said that complete proof has been adduced in favour
of either view. But the latter theory explains most easily the
majority of the facts, while the former has for support the
ready convertibility of the X-rays and " secondary " p radia-
tion, though with the pulse theory there is no great difficulty in
considering that since an electron possesses around it an
electro-magnetic field, and when stopped it is the inertia
of this field which continues in motion and gives rise to a
pulse in the ether. The energy of the pulse may be absorbed
by obstructing matter, but addition of energy to an atom in
that way is almost similar to adding an electron, and so
an electron is released from the atom and forms a secondary
ray. Recently, Professor Barkla has been able to demonstrate
the reflection of X-rays from the cleavage planes of a crystal
of rock salt. The narrow pencil of X-rays was allowed to fall
at grazing incidence, and the principal secondary pencil of
rays formed was one obeying the laws of reflection from the
cleavage planes. It has also been possible to demonstrate the
formation of Interference Fringe systems : a diverging beam
of radiation was so directed on to a crystal that various
portions of the beam were directed at different angles on the
crystal cleavage planes ; it was found that the intensity of the
reflected pencil varied periodically with varying angle of
incidence, and that such maxima of intensity that were
obtained could be explained by the interference of the various
reflected radiations from different equal spaced parallel planes
within the crystal. The wavelength works out to be
•6X 10 ~'J centimetres which agrees with the probable wave-
length of the X -radiations from other considerations.
These experiments have added to many others carried out
by Professor Barkla and his collabrators in favour of the
Ether pulse theory of the Rontgen rays.
"THE DYNAMICS OF PIANOFORTE TOUCH."—
This is the title of a paper by Professor Bryan read before
the Physical Society on February 14th ; the automatic piano
player, unlike the gramophone, has not been given great
May. 1913.
KNOWLEDGE.
187
prominence in scientific literature. Professor Bryan has now
introduced the subject and has, moreover, invented a device
which improves the mechanical player in connection with its
" touch." The theories of Helmholtz and Kaufmann on the
action of the pianoforte are very incomplete and do not take
into account either the sounding board or the time and nature
of the impact of the striking keys. It is this last factor which
controls the quality of the tone given by the vibrating wire,
and the quality of the tone is regulated by the " touch " of
the pianist ; the problem is whether a mechanical player can
be devised which will be capable of adjustment so that its
touch can be modified. Professor Bryan, by means of a
lever which regulates the air pressure, has succeeded in
imitating mechanically to some degree the touch of the
human hand. Still, the touch and emphasis which can be
given by the hand to a single note amongst many others
within a number of chords is still a problem which it would
seem to be somewhat difficult to solve in a mechanical player.
UNDAMPED OSCILLATIONS.— Electrical waves can
be produced either in a continuous train or as a succession
of damped vibrations, as with the oscillations produced for
the purpose of wireless telegraphy by means of the spark
discharge. The production of a continuous train of waves is
the type of oscillation which is employed by Poulsen in his
systems of wireless telegraphy and telephony. An oscillation
circuit of this type can be conveniently set up for laboratory
purposes in the following way, and it may be pointed out that
it is a very convenient method of obtaining discharges through
gases at low pressures, when it is not possible to use metallic
electrodes.
An arc is constructed of copper and carbon, the carbon
is fitted in a brass tube, which passes air-tight through another
brass tube fitted through an indiarubber cork ; the carbon
can be rotated or moved in and out by rotating the brass
tube. The copper is screwed to the end of a brass tube
passing through a rubber cork, and down which passes an
iron tube through which water passes into the brass tube ; the
copper electrode can thus be cooled. The corks fit into the
ends of a silica tube, which is cooled by an outer tube, through
which water passes. The arc is connected through suitable
resistance, giving about two or three amperes, to the two
hundred volt mains. The arc is also connected to a variable
inductance — a coil of insulated wire wound on a wooden
frame, and so bared that a slider brings in more or less
inductance, and a variable condenser connected in series. If
a. large inductance and capacity, consisting of a long coil of
fine wire wound on a tall glass cylinder, is connected to one
end of the first inductance, electrical oscillations are set up
and are of sufficient intensity to illuminate vacuum tubes
situated several feet away.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A.
UTILITY OF SENSITIVENESS TO LIGHT.— It is
well known that many animals are very sensitive to different
degrees of illumination — some seeking more light and others
less. Dr. V. Franz gives some good illustrations of the utility
of this sensitiveness. Many larvae hatched on the floor of
the sea make for the light, which is the best thing they can do
for nutritive and other reasons. Still more frequent is the
case of animals which show marked light-sensitiveness only
when some unusual conditions have intervened, such as per-
turbations in the water or foulness of water. They retreat in
the direction of the light conditions they are accustomed to.
They make for stronger or weaker light, as the case may be,
and the degree of illumination has a directing influence in a
sense. But it is not the degree of illumination in itself that is
significant ; it is the avoidance of concomitant unpropitious
conditions.
MANGANESE IN ANIMALS.— It has been usuallv
supposed that traces of manganese detected in various
animals wore accidental and without physiological significance.
But that is not the view taken by Messrs. Bertrand and
Medigreceanu, who have found manganese in dog, boar, pig,
ox, sheep, horse, rabbit, guinea-pig, seal, dolphin, fowl, duck,
angler, herring, and dogfish. It occurs everywhere in these
animals except in white of egg. There is great diversity in
amount, the maximum occurring in the oviduct of birds.
Liver and kidneys contain more than muscle or nerve.
There is a relatively large amount in hair, feathers, and
nails. The authors maintain that manganese must have
some physiological significance, probably as a catalytic agent.
PERCHING IN BIRDS.— From the time of Borelli it has
been stated that the tendon of the ambiens muscle in many
birds is continued over the knee, and enters into connection
with the tendons of the perforati muscles which bend the
toes. When the knee is bent, the story runs, the ambiens
tendor is stretched, and through the mediation of the others,
clinches the toes on the branch. Professor Brauer points out
that the ambiens (which starts from the spina pubica) is
connected by its tendon with the tendon of the flexor of the
second or third toe, or with the third and fourth (which are
closely wrapped up together), but that it has nothing to do
with the bending of the first toe. In fact, its importance has
been greatly exaggerated. It has little effect in bending the
toes, and it is absent in many birds which ought theoretically
to have it. The bending of the toes is due to the perforati
muscles and the tightening of their tendons when the inter -
tarsal ankle joint is bent.
REPRODUCTIVE DISHARMONY IN WILD DUCK.—
Julian S. Huxley calls attention to a remarkable "disharmony,"
to use Metschnikoffs term, in the reproductive habits of the
wild duck (Anas boschas). The sexual appetite is extended
through the period of incubation. When the female is
actually on the nest this cannot be gratified ; hence, when a
female leaves her nest, she is often pursued by a number of
unsatisfied males. This may readily end in the drowning of
the overtaxed female. At Tring Reservoirs a considerable
number (probably seven to ten per cent.) of the females are
killed in this way every year. This is a noteworthy loss to
the species, due to a disharmony within itself.
EXTRAORDINARY REGENERATIVE CAPACITY.—
E..Uhlenhuth removed the eyes and the surrounding skin
from the larvae of salamander and newt (Salamandra
maculosa and Triton alpestris), and implanted them in the
back of other larvae of the same species. The implanted eye
first underwent degeneration, and the visual cells disappeared.
But after some weeks there was regeneration, and the retina
showed the typical structure. The optic nerve grew, and with
the co-operation of the adjacent tissue, it formed a long strand,
which in certain conditions may grow into connection with a
spinal ganglion.
A KING-CRAB ON THE SURFACE.— R. B. Seymour
Sewell reports from the "Investigator" the capture of an
adult king-crab (Limulus nioluccanus) in a large surface
tow-net, allowed to drift with the tide from an anchored
vessel, and kept on the surface by means of a bamboo float.
How an animal, so obviously a dweller on the floor of the sea,
had been carried or made its own way to the surface remains
a mystery.
HABITS OF TRILOBITES.— Hans V. Staff and Hans
Reck have made an interesting and ingenious attempt to work
back to the habits of these ancient extinct types. They argue
from structural peculiarities to the mode of life. The primi-
tive Trilobites were creeping animals, and some retained this
habit. The Olenellus type illustrates adaptation to creeping.
But some, such as Phillipsia and Illaenus, became swimmers;
and some went further, like the laterally-expanded Deiphon-
Acidaspis types, becoming adapted to plankton-drifting.
Some, like Dalmanites, got long terminal spines suited for
creeping in the King-crab fashion. Some, which had pro-
gressed on the swimming line of evolution, relapsed and became
creeping types again. There is a fascination in this attempt
to put life into fossils, making them move about again each
after its kind.
SOLAR DISTURBANCES DURING MARCH, 1913.
BY FRANK C. DENNETT.
Only one day has been quite missed during the month,
namely, March 4th. The spot disturbances have been both
few and insignificant in appearance, yet one at least was of
importance. The disc appeared to be quite free from disturb-
ance on twelve days (3rd, 7th, 9th, 10th, 15th to 17th, 22nd,
23rd, 26th, 27th, and 31st). The central meridian at noon on
March 1st was 309° 17'.
On March 8th, at 1.30 p.m., there was an evanescent group
of minute pores in high southern latitude, but clouds prevented
the exact determination of their position. Observations
earlier in the day failed to reveal them.
No. 5. — A small pore close to a faculic patch seen on the
13th and 14th only. It was specially noticeable owing to its
high latitude, 34° South.
No. 6. — A group of pores only seen on the 28th, very near
to the equator.
The photosphere appeared to be in an active state on the
27th, dull spotlets appearing and disappearing in the north-
western quadrant.
Faculic patches were visible in the south polar regions on
the 5th, 6th and 8th, also on the first two dates close to the
equator, near longitude 180°. On the 1st and 2nd the faculic
remains of No. 4 were visible near the north-western limb,
and from the 18th to the 21st were advancing from the north-
eastern limb, re-appearing on the 29th as they approached
the north-western limb. On the 29th and 30th another
patch around longitude 225° was visible near the north-
eastern limb.
Our chart is constructed from the observations of Messrs.
John McHarg, E. E. Peacock, W. H. Izzard, A. A. Buss, and
the writer.
DAY OF MARCH.
3
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7 6 1 i
£££
l. 25 I, 28 V. X IS.
15"
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CORRESPONDENCE.
PHYLLOTAXJS AND THE DISCAL FLORETS OF
COMPOSITE FLOWERS.
To the Editors of " Knowledge."
Sirs, — A few months ago I published a paper in "Know-
ledge" on the ray and discal florets of Seuecio Jacobaea.
The following note is a supplement to it. The plant, of which a
specimen is appended, so that you may have it identified, is
fairly common about Cordoba. In appearance, it is something
between our blue cornflower and a rampion, with the colouring
of the latter. It is well-suited for the purpose, the sterile ray-
and fertile discal-florets being neither of them very numerous,
but there was not enough of the plants to repeat, on anything
the least like the same scale, the elaborate observations on the
small wild calendula, nor for that matter was there any reason
for attempting it. At the same time the present observations
seem to put beyond any reasonable doubt the fact that the
coincidence shewn in the number of the florets with numbers
indicating a system of concentric rings is far more than
chance would give. The reasoning is simple enough, and I
do not think there is any serious flaw in it. The number
of circular ring systems was found for the digit series from
the lowest discal number to the highest discal number + the
ray florets, and the percentage of coincidences was found to
be nearly three times what chance would give. Taking, how-
ever, what may be considered the normal types of flower head
with 17, 18 and 19 rays, the percentage was much higher. In
fact, for the 18-rayed type it was 90-9 instead of 20%. For
the sake of brevity QT), (V), (jf), and so on, are put for " a
system of concentric rings beginning with 3, 4, 5, and so on."
When a number has one dot over it, that means that it
belongs to a ring system, either with or without the ray
florets being counted in; when two, that it belongs to both.
Table 36.
Giving all the ring systems in the tract of numbers to
be dealt with, viz., from 28. ..to 100 or 72.
Ring System.
No. of Concentric Rings.
3
4
5
Beginning with a ring of 3
4
*t n M
,, ,, ,, J •••
6 ...
7
,, ,. ,, / •••
>i » » 8 •••
39
42
48
52
56
60
64
68
75
80
85
90
95
100
\i
May, 1913.
KNOWLEDGE.
189
Table 37.
Results of first counting : —
Rays.
Flower
Heads.
Discal Florets.
11
12
13
14
15
1
0
1
1
4
16
17
18
19
20
21
22
5
7
7
12
5
5
0
39, 41, 54, 56, 61
50, 50, 51, 52, 54, 56, 63
42, 48, 49, 64, 64, 69, 56
46, 48, 49, 50, 53, 56, 56, 62, 63, 66, 68, 71
53, 58, 59, 62, 69
49, 72, 74, 78
41
Nine ring systems in 39 corresponds to 23%.
Thirteen coincidences in 41 counts to 31%.
There are, however, 13 coincidences, one off, so that we
have about li what chance should give.
* If we count in the rays we have numbers from 55... 99, in
which series there are again 9 ring systems or 20%. Excluding
the ring systems under 52 we then have just 15 coincidences,
or about 34%.
Table 38.
First
and subsequent countings together : —
No. of
Ray
Florets
Flower
Heads.
Discal Florets.
13
3
28, 29, 41
(3)
14
4
35, 35, 44, 46
(4)
15
11
35, 38, 40, 42, 43, 45, 47, 53, 53, 62
(10)
16
10
39, 39, 41, 41, 43, 49, 51, 54, 56, 61
(10)
17
is J
35, 39, 40, 43, 46, 46, 48, 50, 50, 51,
I
[51, 52, 54, 56, 63, 65, 65
(18)
IS
11
34, 39, 42, 48, 49, 50, 60, 61, 64, 64
(11)
19
"1
44, 46, 48, 49, 50, 51, 53, 54, 55, 56 (-,)
[59, 62, 63 (a), 66, 68, 71
(19)
20
9
44, 49. 53, 58, 59, 62, 65, 69, 70
(9)
21
8
49, 54. 72,74, 75, 78
(6)
22
1
64
(1)
94
Thus the total number of coincidences is 48. The range is
28 to 99 or 71 with 13 ring systems.
13 x
71
77^. = 18-3% ring systems.
48 x
-jrr = , 0(; =52-8% coincidences with ring systems, or nearly
three times what chance would give.
If, however, we take the three commonest forms 17, IS, 19,
with the most numerous countings we get 17 range 35. ..82,
i.e., in 47 digits there are 10 ring systems or 21 -25...% obser-
vation gives 55-5%.
18 range 34. ..82, 48 digits with 10 ring systems or 20-8%
observation gives 90 • 9%.
19 range 44. ..90, 46 digits with 11 ring systems or 24-0%
observation gives 57-8%.
21, 20-0% observation gives 50%.
W. W. STRICKLAND.
HEN BIRDS ASSUMING THE PLUMAGE OE THE
MALE BIRD.
To the Editors of " Knowledge."
Sirs. — The experiments carried out at Graaff Reinet, Cape
Colony, in removing the ovaries of the hen bird in Ostriches
and thereby causing the plumage to be that of the male bird,
are very interesting.
As is well known, hen pheasants and probably hens of
poultry, also assume the garb of a male bird if the ovaries
become diseased, or are removed, and it would be interesting
to carry the experiment still further, and find whether all hen
birds would be affected in the same way. I think it is probable
that it would be so.
Some years ago an old male Ostrich in these Gardens
assumed the plumage of a hen bird, and was evidently badly
diseased before the change occurred, as he shortly after died ;
unfortunately I was absent at the time, so the skin was not
preserved.
The effect of the removal of ovaries in animal life is well
known.
DUDLEY LE SOUEE. C.M.Z.S., Director.
Zoological Gardens,
Melbourne.
ON THE RELATIONSHIP OF APERTURE TO
POWER IN MICROSCOPE OBJECTIVES.
To the Editors of " Knowledge."
Sirs, — After reading Mr. Hutton's interesting article on the
craze for aperture, which appeared in "Knowledge"
for February, I looked up some of the points in Wright's
" Principles of Microscopy " and came across the following,
which raised the question, " How are we amateurs to decide
when doctors disagree." On page 225 the following is
given : —
" Example : In the case where a 100-fold magnification is to
be exacted . . . and where our choice lies between .
N.A.'s of 0-6 and 0-3 respectively, preference ought, other
things being equal, to be given to the former. The 0-6
objective would not only gather in more light into the image
and give better resolution in depth, but it would give us the
required magnification in association with a terminal beam of
0-006 N.A., i.e., a beam which would fill the whole aperture of
the pupil. The 0-3 objective would, in association with a
hundredfold magnified image, give us a beam of 0'0003 N.A.,
i.e., a beam whose diameter would be less by one half than
the diameter of the pupil."
The differences between the two writers is curious. Mr.
Hutton, taking the average power of resolution of eyesight at
one hundred and twenty five lines to the inch, gets an N.A. of
0-13, sufficient with a magnification of one hundred. Sir
A. E. Wright, taking the diameter of the pupil, recommends
an N.A. of 0-6 for the same magnification. Thus, while both
are guided by the limits of human eyesight, the results they
arrive at are widely different.
Nor is this the only difference between the two writers, for
Mr. Hutton says: "Besides, we sacrifice depth of focus" by
going in for a larger aperture, whereas, according to Sir A. E.
Wright, quoted above, the higher N.A. gives " better resolution
in depth."
Riverside,
Castle Street,
Salisbury.
C. H. De MF.LLO.
REVIEWS.
CHEMISTRY.
Modern Inorganic Chemistry. — By J. W. Mellor, D.Sc.
871 pages. 316 illustrations. 8*-in. X 5i-in.
(Longmans, Green & Co. Price 7/6.)
No one who has had any experience in teaching chemistry
can fail to have been struck with the difficulty of inducing a
beginner to get a grasp of the general principles of the science
as distinguished from the numberless facts upon which they
are based. This is often lost sight of, however, in text books,
largely because a knowledge of detail "pays" best in examina-
tions. It is, therefore, a pleasure to meet with a book in
which stress is laid upon the point that it is more important
to train the reasoning faculty than the memory. In fact, the
views of the author on this point may be summarised in the
aphorisms that we find in different parts of his book ; as, for
example, " The best chemist is not necessarily he who is
familiar with the greatest number of compounds ; " and " Dic-
tionaries of chemistry, not the memory, are the natural store-
house of isolated facts."
At the same time, it must not be inferred that the facts
essential to understanding a theory are omitted. On the con-
trary, throughout the book the evidence for and against
particular views is cited, and the student is, to a large extent,
encouraged to draw his own conclusions. The only instance
where generalisation seems to have been carried too far is in
the account of the elements of the rare earths, to which only
two pages are given.
The chapter upon radioactivity is particularly clear and
full, and is well illustrated by diagrams. Although the author
does not expressly say so, he evidently regards the experiments
of Sir William Ramsay upon the transmutation of copper into
lithium and sodium as " not proven." Prominence is also
given in this connection to the view of Professor Armstrong
(1912) that "radioactive elements" may not be really elements
at all, but compounds of ordinary elements with helium.
The book is quite sufficiently advanced to deserve references
to the original authorities, so that any student may be
encouraged to follow up a subject further. This would add
greatly to the value of the work.
In an epilogue, Dr. Mellor remarks : " The teacher has
failed in his work if he has not whetted the student's appetite
for more." If we apply this standard to his own book we can
say without hesitation that no one with any taste for chemistry
can read it without being interested and stimulated both by
the matter itself and the way in which it is presented, with
appropriate quotations from great chemists and natural
philosophers as introductions to the different sections.
C. A. M.
Questioned Documents. — By Albert S. Osboun. 501
pages. 200 illustrations. 10-in.X7-in.
(London Agents for American Publishers: Sweet & Maxwell.
Price 30/- net.)
This book belongs to a class of works against which
objections are sometimes brought upon the grounds that they
may be of use to criminals and so defeat their own end.
But we venture to think that no one who studies Mr. Osborn's
most valuable book will endorse this view, for it will be seen
that the pitfalls are so numerous that in avoiding one a forger
must inevitably fall into another.
Every scientific question which has to be answered in
deciding whether a document is genuine or not is here fully
discussed, and the author rightly lays stress upon the point
that a reason ought to underlie every expression of opinion
upon a matter of this kind.
The methods used in the examination of the writing, the
paper, the ink, and so on, are described at length, and well
illustrated with diagrams and photographs of exhibits in actual
cases in which Mr. Osborn has been engaged.
Throughout the book the use of scientific appliances is
advocated wherever practicable. Special cameras and
microscopes are described and directions are given for the
most suitable methods of applying them to the examination
of documents; micrometer callipers and micrometer eyepieces
are to be used for the measurement of lines and spaces ; and
the tintometer for recording differences in colour.
In dealing with the judgment of handwriting the author
gives an excellent survey of the more modern and scientific
methods of solving a very difficult problem, while a separate
chapter is devoted to the effect of the position of the pen, and
the pressure applied to it, upon the character of the writing.
There is only one important direction in which we can
suggest an improvement for a future edition. A short outline
of each of the illustrative cases so frequently cited in the text
might with advantage be added in the form of an appendix,
as is done in Mr. Justice Wills' " Circumstantial Evidence."
This would add greatly to the interest of the work without in
any way detracting from its scientific value.
But even in its present form the general reader will find
much to entertain him in this book, while to the lawyer it
should prove invaluable. It has already met with a warm
welcome in America, and it only requires to become known to
be equally in demand in this country. r 4 m
The Problem of the Gas-Works Pitch Industries and
Cancer.— By H. C. Ross, M.R.C.S., L.R.C.P., J. W. Cropper,
M.B., M.Sc, and W. J. A. Butterfield, M.A., F.I.C.
48 pages. 2 illustrations. 8i-in. X 5-2-in.
(John Murray. Price 6d. net.)
For some years past the prevalence of warts, ulcers, and
epitheliomatous cancer among persons engaged in the distilla-
tion of gas-works tar and and the manufacture of briquettes
from gas-works pitch has been recognised, but hitherto no
explanation has been given of the remarkable fact that the
similar pitch from blast-furnace tar does not produce these
effects.
In this little book we have the interesting results of a
research made by two physiologists and a chemist in an
attempt to discover the causes of this phenomenon. Starting
from the hypothesis that cancer is the result of certain factors
which include (1) rapid proliferation of cells upon a chronically
injured site ; and (2) an abnormal tendency of these cells to
migrate into neighbouring tissue, experiments were made to
discover what chemical agents were capable of stimulating
these tendencies to rapid growth and abnormal migration.
The method employed was based upon the fact discovered
in 1909 by Drs. Ross and Cropper that human white blood
cells could be made to reproduce by cellular division, in
response to the action of certain chemical substances such as
creatinine, methylamine, and other compounds (extracted, e.g.,
from dead animal matter). Some thirty-one different sub-
stances were discovered, capable of causing such cell prolifera-
tion, and to these the name of auxetics was given. The
action of these compounds was also proved physiologically ;
for, when applied to the surface of ulcers, they produced
granulation tissue and accelerated the healing process.
A second class of bodies, working in association with auxetic
agents, caused unsymmetrical division of the blood cells and
excited amoeboid movements which would give rise to infil-
tration of the cells into neighbouring tissue. These bodies
were termed kinetics. Now, in experiments with aqueous
extracts of the two kinds of pitch, it was found that that
derived from the gas-works contained both auxetics and
kinetics, but that the extract from blast-furnace pitch, while
containing a small amount of auxetics, showed no signs of
kinetics, and did not produce amoeboid movements in the white
blood cells.
190
May, 1913.
KNOWLEDGE.
191
From this the conclusion was drawn that the pathological
effects of gas-works pitch was the result of chemical injury
and not of mechanical injury caused by irritation produced by
the coal dust, as had previously been supposed. Attempts to
remove these chemical substances by washing the pitch were
successful on a small scale, but washing would not be
practicable in the works, since it would interfere with the
binding properties of the pitch.
The results of fractional distillation of the tar showed that
it was not possible to eliminate the dangerous products at a
lower temperature than 360°C, and that pitch which had
been heated to that extent was useless for practical purposes.
Washing the tar with hot water before distillation completely
eliminated the auxetics and kinetics, and the pitch from such
tar would be as valuable as that now used in making
briquettes. There would certainly be difficulties in the
manipulation of the tar, but these should not be insuperable.
Such, in brief, is an outline of the main results and con-
clusions of a most striking investigation attacking the cancer
problem from the chemical side. Further researches are now
being made to isolate the definite chemical compounds from
the gas-works tar and pitch, and since the publication of the
present work it has been discovered that there is a pronounced
difference in the proportion of auxetics and kinetics in
different kinds of coal. This is one of the reasons why
blast-furnace pitch (largely derived from hard coal) does not
produce the effects of gas-works pitch (from bituminous coal).
Another factor is the difference of temperature at which the
two kinds of tar distil.
The details of this investigation have been communicated to
the Home Office, and they appear so convincing as to the
causes of the evil, that it ought to be possible to devise
precautions that will entirely prevent it.
C. A. M.
GEOGRAPHY.
Papua or British New Guinea. — By J. H. P. MURRAY.
With an introduction by Sir William MacGregor, G.C.M.G.,
C.B., D.Sc. 388 pages. 38 illustrations. 9-in. X6-in.
(T. Fisher Unwin. Price 15/- net.)
Of all the British possessions few are less well known than
Papua. There is a great deal of pioneer work to be done in
all directions. The geology and the natural resources, the
geography and ethnology have been only superficially investi-
gated, though at present investigations on all of them are being
pursued. Most people seem to associate New Guinea with
rain and perpetual mists, and a book which helps to dispel
these mists and others that cloud general knowledge of this
most interesting land is decidedly welcome, and does not need
the apology with which the modest author prefaces it.
Some peculiarities of the people of Papua are very striking.
For instance, on Rossel Island, to the south-east, traces of
separate languages for men and women are found. The dis-
abilities of women are curious. On Rossel they must not
speak in a canoe, and the native, on being asked what would
happen to one who transgressed, suggests that she might
probably be eaten, but refuses to contemplate such an un-
heard-of occurrence. Even the men of Rossel speak a
different language when they are on the neighbouring island of
Roa, for some mysterious reason. On the Gulf of Papua,
again, we find a South Sea snobbery. The possession of tails
is imputed to the despised tribes. One native relates of a
race of tailed men that they sit with their tails hanging through
holes in the floors of their pile-dwellings. While among them,
he used, for a joke, " to creep under the house, take hold of
each tail very gently and tie a knot in it " ; then raise an
alarm, with the result that the caudate warriors, springing up
to meet the foe, were jerked on their backs by their own
tails. Another has conclusive evidence of the existence of
one tailed man at least, " Because I eat him ! " — all fairly
strong evidence, remarks Mr. Murray, if not of the existence of
men with tails, at least of lively imaginations. And so we are
taken through interesting chapters on the People, History,
Exploration and Development. One is struck with the sym-
pathetic and far-sighted policy of the Australian Government
which guides the destinies of the Possession, and recognises in
Mr. Murray, who is the Lieutenant-Governor, a wise and
thoughtful exponent of it.
We do not think the introduction very fortunate, and the
two first chapters, on the geography, are certainly the least
interesting. The numerous photographs are excellent, but the
map is not very satisfactory, and there are a few misprints.
The index is good. . <,
The Earth, its Shape, Size, Weight and Spin. — By J. H.
Poynting, Sc.D., F.R.S. 141 pages. 49 figures.
6i-in. X 5-in.
(The Cambridge University Press. Price 1/- net.)
In three chapters, on " The Shape and Size of the Earth,"
'* Weighing the Earth," " The Earth as a Clock," Dr.
Poynting has collected for the student and the general reader
a great deal of useful information on certain branches of
earth-knowledge for which one has usually to search large and
difficult treatises, and the information is presented in such a
way that it is acquired really as scientific knowledge, not
merely as positive fact is got from the usual popular book.
The student must have a preparation in Mathematics and
Physics, but the general reader will read with profit though his
equipment be less.
Very fresh and stimulating is the treatment of Relative
Motion, Precession and Nutation, and most of the part on the
Tides. Frequently the expression is striking and illuminating.
It is characteristic of many of the Cambridge Manuals that
exactly as the reader knows more he learns more, and this is
even more than usually true of the present volume. One
complains of some things that might be easier to follow, as at
pages 11-12, 58, 115. These are but slight faults in a book
elsewhere remarkably excellent, which is well got up, and has
a good index.
A. S.
GEOLOGY.
The Geology of Soils and Substrata. — By H. B. Woodward,
F.R.S., F.G.S. 366 pages. 44 text-figures. 4 plates.
7i-in.X5-in.
(Edward Arnold. Price 7/6 net.)
The aim of this book is to provide the necessary geological
information for agriculturists, and those engaged in the
management of estates, in sanitary or engineering work — in
short, any business which involves some knowledge of the soil
and subsoil. The practical importance of geological know-
ledge is nowhere brought out more fully than in connection
with agriculture, sites for houses and cemeteries, sewage
disposal, and kindred applications of the science. In our
opinion, Mr. Woodward has fully achieved the object with
which he set out. In the book is brought together an immense
amount of geological information on subjects that are rarely
even mentioned in the text-books, and it is a special con-
venience to have it set out so clearly in this book.
The first six chapters provide such general geological know-
ledge as is necessary for the study of the soil and subsoil that
follows. The next eight chapters deal with every conceivable
phase of agricultural work in which geological knowledge is a
desideratum. For instance, besides the method of formation
of soils, we are shown how climatic and other conditions
affect its fertility or cause its barrenness. This leads to a dis-
cussion of the drainage necessary to increase the fertility and
workability of the soil, and of the geological principles in-
volved.
Next are described the mineral manures which it may be
necessary to apply in order to make up some natural deficiency
in the soil. Then come chapters on the geological features to
be studied in connection with forests, woodlands, orchards
and gardens ; and the practical geological considerations in
respect to estate management, and economic materials (such
as road-metals) derived from the soil or subsoil. The chapter
dealing with the geology of sites for houses, cemeteries, sewage
192
KNOWLEDGE.
May, 1913.
farms, water supply and ponds, is of special value. The re-
maining chapters describe the soils and subsoils derived from
each of the various geological formations in Great Britain, and
in this part of the book a large amount of practical informa-
tion has been brought together. At frequent intervals there
are appended good lists of references, and the book is illus-
trated by excellent plates and text- figures. r ... _.
ZOOLOGY.
Comparative Anatomy of Vertebrates. — By J. S. Kingsley.
401 pages. 346 illustrations. 9-in. X 6-in.
(John Murray. Price 12/- net.)
With such a multitude of works on the anatomy and
anatomical evolution of the vertebrata already before the
public, it might well have been thought that there was
scarcely even standing room for a new one. Such, however,
is evidently not the opinion of Professor Kingsley, who
occupies the chair of Biology in Tuft's College. Apparently,
as a reason for the new venture, it is stated in the preface
that the modern method of teaching biology in the laboratory,
by means of dissection, does not constitute a science, and
that it is consequently essential that the facts so collected
" should be properly compared and correlated with each other,
and with the condition in other animals. It is the purpose
of the author to present a volume of moderate size which may
serve as a framework around which these factors may be
grouped, so that their bearings may be recognised, and a
broad conception of vertebrate structure obtained. In order
that this may be realized, embryology is made the basis, the
various structures being traced from the undifferentiated egg
into the adult condition."
That Professor Kingsley has done his work thoroughly and
in first-rate style every student who has cause to make use of
the book can scarcely fail to admit : the amount of informa-
tion which has been crammed into such a small space being
little short of marvellous, especially when the number and, in
some instances, the relatively large size of the illustrations are
taken into consideration. For excellence of execution, clean-
ness of detail, and suitability to their respective purposes
these illustrations can scarcely be surpassed. In the legend
to Figure 92, we notice, however, that the American fashion of
applying the term "turtle" to a fresh-water "tortoise" is
retained ; and we cannot approve of the practice, as
exemplified in the same illustration, of referring the reader
to a figure twenty pages earlier for an explanation of most
of the lettering. Neither do we like the Americanism of
spelling the name of the European pond-tortoise Emys
europea. Save for trivial criticisms of this nature, we have
nothing but unqualified praise to bestow upon Professor
Kingsley's book, which ought to have a wide circulation among
university and other students.
K. L.
Heredity. — By Professor J. Arthur Thomson, M.A.
627 pages. 47 illustrations. 8|-in.X6-in.
(John Murray. Price 9/- net.)
Professor Thomson is to be heartily congratulated on the
issue of a second edition of this volume, which forms the best
semi-popular text-book on this interesting and important
subject, and is long likely to maintain this enviable position.
Apparently, the new edition has not required much alteration,
with the exception of the correction of a few errors ; but the
author has taken the opportunity of adding references to
papers embodying discoveries made since the appearance of
the first edition.
Doubtless many of our readers are familiar with the work
in its original form, and to these anything like a review would
prove wearisome ; those who have not yet made its acquain-
tance are recommended to remedy the omission with the
least possible delay. For heredity is a subject in which we
are all nowadays more or less practically and directly interested
in — or, if we are not, we ought to be ; and whether we
believe or disbelieve in eugenics as a potential factor in
modern life, we ought at all events to be acquainted with the
arguments in favour of the new doctrine.
To the general reader, perhaps, the most interesting part
of the work is contained in the concluding sections, where
the author reviews the effects of heredity on the present
population of our country. After referring to the well-
ascertained fact that while the children of exceptionally gifted
parents are not infrequently worse than commonplace (as if
nature had exhausted herself in the special mental development
of the former), those of parents of a low type are often very
fair examples of the human species, Professor Thomson pro-
ceeds to discuss the question whether modern therapeutic and
hygienic methods tend to prevent the elimination of weaklings,
and thus lead to the deterioration of the race as a whole.
Here it is pointed out that insanitary surroundings, and the
consequent epidemics, affect the strong as well as the weak,
while the latter may in some cases develop mental character
not vouchsafed to the former. On the other hand, the
question whether bodily weaklings should be permitted to
transmit their failings presents a more serious question.
Whether the relatively unfit should be allowed to multiply
is another serious question of the same nature, which the
author answers unhesitatingly in the negative. The burden
of militarism, and the consequent destruction from time to
time of the flower of our manhood, is also discussed at some
length, with the suggestion that certain kinds of deterioration
may be due to this cause. With this we take leave of a
fascinating volume, on which the reading and thinking world
has already bestowed its imprimatur of appreciation.
R. L.
Problems of Life and Reproduction. — By Marcus Hartog.
362 pages. 41 illustrations. 8J-in. X 5if-in.
(John Murray. Price 7/6 net.)
We learn from the preface that the author, when incubating
the idea of this volume, had in his mind to write a general
treatise on reproduction suited to the needs and capacity of
the non-scientific reader. Further consideration indicated
the existence of certain reasons against such a mode of
procedure, and these reasons — to our thinking, unfortunately —
ultimately prevailed. The author found, however, that he
had already written certain articles on reproduction — one so
long ago as 1892 ; and these, with others on more or less
distinct subjects, have been collected and reproduced, with
such alterations as were deemed essential, in the present
volume, which is consequently a kind of scientific olla
podrida, and a very mixed one at that. For it includes such
diverse topics as reproduction and fertilisation, the trans-
mission of acquired characters, mechanism and life, the
biological writings of Samuel Butler, the teaching of nature
study, and — what we venture to suggest will prove a regular
stumper to the man in the street — the new force, mitokinetism.
But whatever Professor Hartog writes, even if it be a bit
unduly technical and in a somewhat involved style, is worth
reading; and those readers of "Knowledge" who wish to
have even a bowing acquaintance with some of the up-to-date
subjects of modern scientific thought, will do well to at least
dip into his pages.
With such a multitude of subjects before him, the unfortu-
nate reviewer who is expected to give something like a
comprehensive notice of the book, within the compass of a few
short paragraphs, must be completely and hopelessly non-
plussed. Personally, we have been most interested in the
article on the inheritance of acquired characters ; but we are
somewhat disheartened by a footnote at the commencement
to the effect that another author has collected a number of
facts in favour of this theory since the first appearance of the
article, which ought surely to have afforded sufficient reasons
for rewriting. Among Darwinists who hope to attain the
Valhalla of orthodox followers of their doctrine, anything
approaching recognition of the possibility of inheritance of
acquired characters (for what these are we must refer our
readers to the pages of our author) is anathema, but Professor
Hartog, being a bold spirit, runs a-tilt at the objectors, and
demonstrates to his own satisfaction, at any rate, that such
characters can, at least in some instances, be transmitted to the
offspring. Whether he will have succeeded in convincing the
orthodox Darwinists of the error of their ways is quite another
matter. ., .
CONSIDERATIONS ON THE PHYSICAL APPEARANCE
OF THE PLANET MARS.
By E. M. ANTONIADI, F.R.A.S.
In the year 1877, our knowledge of the markings
which variegate the surface of Mars was in a very
satisfactory condition. A series of excellent
observations by Dawes, Lockyer, Lassell, Kaiser,
Burton, Green, and others, had disclosed the true
natural structure of the spots on that planet. The
From a />Iiot<>graph
by t lie. Writer
Figure 183. View of the Great Dome of the 33-inch
Refractor at Meudon.
Height of the ground above sea level, 533 feet.
question thus appeared definitely settled, when it
was troubled by the Italian astronomer Schiaparelli,*
who announced that linear objects, to which he gave
the name of channels, or canals, were furrowing the
so-called continental regions of our neighbour in
space. During the apparitions of Mars following
the year 1877, the Milan observer continued and
extended his discoveries ; his later maps seemed
practically covered with spider's webs ; while the
zeal and discernment of his followers could number
no less than one thousand different canals on the
yellow or grey expanses of the planet.
Gigantic watercourses, mostly running along
great circles of the sphere, and, consequently,
appearing straight near the centre of the disc,
continued to look straight in Italy even when
nearing the limb of Mars. A geometrical cross of
canals in the land called Hellas was seen attended
with four symmetrical bright specks of light, re-
calling somehow to memory the In hoc signo vinces
of the emperor Constantine. Canals, scores of
miles wide, and hundreds of miles long, were
observed in a few days, or even hours, to double,
cither by the formation of a parallel band, or by the
disappearance of the original canal, and by the
formation of two new parallel streaks separated by
hundreds of miles. Nor were hesitations in these
doublings neglected to be put on record, since canals
were seen to be alternately single and double on the
same night.
To account for these wonderful phenomena, the
vast powers of Nature were found totally inadequate ;
and thus it was that Schiaparelli was led to
enunciate the idea of the artificial origin of the
canals, conceiving the larger of them to be composed
of six different watercourses, whose dykes would
be opened now and then by the Martian minister of
agriculture.
Speculations of such a character were eagerly
embraced by M. Flammarion and other popular
Continental writers. Yet it is to be regretted that
the originator of this artificial theory, and his
imitators, have failed to do the utmost with their
cherished idea. For, inasmuch as the canals
appear straight about the central meridian, and
also when carried by rotation near the limb, it is
obvious that the Martian engineers would be con-
stantly engaged in rapidly digging and destroying
their watercourses, so as to make them look always
straight to the observers on the Earth.
It is to the credit of British science that the
results of Schiaparelli were, from the very onset,
strongly controverted by English astronomers. In
1879 Green boldly questioned the reality of these
canals. In 1882 Mr. Maunder and Mr. (now Sir)
William H. M. Christie rightly insisted on the
error of Schiaparelli in using too high powers.
But the honour of first recognising the true
nature of the minor detail of the planet is due
to Mr. W. F. Denning, who announced, as far
back as 1886, that the continents of Mars show
Figure 184. The Laestrygon. Figure 185. The Jamuna.
1806, June 12. 1894, August 27.
Single and double Canals of Mars, as glimpsed for a quarter
second by the Writer.
here and there some irregular streaks, presenting
frequent interruptions and condensations. As is wont
This view of the discovery of the canals was given by Mr. Maunder, in " Knowledge " for 1894, p. 249.
193
194
KNOWLEDGE.
May. 1913.
in such cases, this statement attracted no attention
at the time ; and it was only several years later that
it received full confirmation at the hands of Professors
Young, Barnard, Hale, and the writer, all observing
with very powerful telescopes. And when we
recollect that Mr. Denning used in this enquiry only
a ten-inch reflector, and that he made his innumer-
able other discoveries in an unfavourable climate,
and under difficult circumstances, we deem it onlv
as
the
itest of all modern
solved bv observation,
just to consider him
observers.
The canal problem, thus
was next approached
from the point of view of
theory. In 1894-1895,
Mr. Maunder laid stress,
in these columns, on the
errorof believingthat our
telescopes reveal to us the
ultimate structure of the
surface of the planet.
As a consequence, he
expressed his conviction
that the canals are only
the summation of a com-
plexity of detail, compar-
ing them with the linear
appearance to the naked
eye of an irregular stream of sunspots. This is the
key to the whole question. " I quite agree with you,"
says so high an authority as Professor Barnard, in a
letter to the writer, " in respect to Mr. Maunder's
1
_
*
Figure 186.
Schiaparelli.
1883-1884.
Figure 187.
The Writer.
1909.
The " Canals " Laestrygon,
Antaeus and Tartarus, as seen in
an aphelic apparition with an
8 J -inch, and in a perihelic appari-
tion with a 33-inch Refractor.
As a patient record of fleeting impressions, his results
stand unrivalled ; while his splendid triangulation
of the Martian surface has victoriously resisted the
test of time.
An unsympathetic feature of most planetary
drawings is the regularity of their markings.
Scientific candour is partly responsible for this, as
the truthful observer will avoid the impossibility of
sketching complex irregularities which he is only
glimpsing, rather than introduce elements of doubt
in his delineation. A less excusable reason for
geometrical outlines may be sought in a widespread
disregard of angular dia-
meters. In fact, areo-
graphers too frequently
forget that Mars is
usually seen as a six-
penny piece held at the
distance of two feet
from the eye ; and
that what is sharp on
such a small disc, so
far off, ought to be
represented as exceed-
ingly vague on drawings
three inches in diameter,
seen at the distance of
one foot only.
The student who passes many consecutive hours
in the study of Mars with medium-sized instruments,
is liable to catch rare glimpses of straight lines,
single or double, generally lasting about one quarter
Figure 188.
Schiaparelli.
1883-1884.
Figure 189.
The Writer.
1909.
The "Canal" Eosphoios
in an aphelic apparition
with an 8J-inch, and in a
perihelic apparition with a
33-inch Refractor.
Figure 190. September 18.
V. Fournier.
J any Desloges Observatory.
1 1 J -inch Refractor.
Figure 191. September 20.
The Writer.
Meudon Observatory.
33 -inch Refractor.
Figure 192. October 5.
From a photograph
by Professor Hale.
60-inch Refractor.
Figure 193. November 3.
Professor Lowell.
24-inch Refractor,
stopped down to some 15 inches.
Views of Syrtis Major and Lacus Moeris in 1909 with various telescopes.
work in trying to clear up the tangle about the
canals of Mars. I think he has thrown much
light on the subject."
Many able observers believed that Schiaparelli
had. imagined all his system of spider's webs. But
this is quite unfair, as, with the exception of an
abuse of magnification, the errors of Schiaparelli
were errors of judgment, and not of observation.
Although the constant use of high powers made him
lose the half-tones of Mars, his outlines of the
dusky areas are usually more accurate than anything
ever drawn with a telescope of the size he used.
of a second (see Figures 184 and 185). Here we
have a vindication of Schiaparelli's discoveries.
But their deceitful character will obtrude itself on
the observer using a large telescope, when, in the
place of the lines, he will hold steadily, either a
winding, knotted, irregular band, or the jagged edge
of a half-tone, or some other complex detail (see
Figures 186 to 189).
In their anxiety to prop their views against
natural law, believers in the reality of the linear
canals have presumed to champion the alleged
superiority of small over large telescopes ; and this
May, 1913.
KNOWLEDGE.
195
Figure 194.
1911, October 28d 22h 19"
Longitude =58°.
Figure 195.
December 4d 22h 0n
Longitude = 87°.
Figure 196.
October 20" 21h 35m.
Longitude = 120°.
Figure 197.
October 17" 21h 55m.
Longitude = 152°.
Figure 198.
October 14d 23h 0n
Longitude=195°.
Figure 199.
October 14d 21h 30"
Longitude = 255°.
Figure 200.
November 13" 22" 45"
Longitude = 282°.
Figure 201.
November 6d 22h 15m.
Longitude = 337°.
Figure 202.
November 3" 21" 48"\
Longitude = 357°.
Observations of Mars in 1911, made by E. M. Antoniadi, F.R.A.S., with the 33-inch Refractor of the Meudon Observatory,
magnifying 320, 540, and 810 diameters.
(Published by kind permission o/ I'rojcssor Henri Deslandres, A.R.A.S., of the French Academy tf Sciences, Director 0/ the Astro-physical Observatory 0/ /'mis,
situated at Meudon (S.-cl-O.), France.)
196
KNOWLEDGE.
May, 1913.
either in revealing planetary detail, or in separating
close double stars. But the attempt has been
defeated, both by theory and observation ;
(a) by theory, because of the law of diffraction,
which proves that the defining power of a
telescope increases with its aperture ; and (b) by
observation, from the evidence of the facts them-
selves. A comparison of the appearance of Syrtis
Major on Mars with various instruments in 1909,
when the weaker telescopes revealed inexistent lines
while failing to show the coarsest details (see
Figures 190 to 193) will establish for ever their hope-
less inferiority. Nor was the smaller instrument
more fortunate on double stars. A spurious
satellite to Sirius was discovered and measured in an
impossible position in 1896, with a refractor of
moderate power. But when the question of finding
the true satellite was seriously raised, the discovery
was naturally made with the thirty-six inch
equatorial of the Lick Observatory, one of the most
powerful instruments in existence.
Thus it is that diffraction fetters the efficiency of
small telescopes ; and their comparison with large
ones is as childish as the attempt to bombard a fortress
twenty miles off with guns whose range is only eight.
Such the errors foisted on the scientific world, and
such the arguments leading to their final refutation.
Yet truth will seldom receive acceptance without
strenuous opposition. The laws of perspective will
again be curbed by the evidence of lines appearing
straight in all positions of a rotating globe. Some
observers will continue proclaiming the superiority of
small telescopes. Ponderous volumes will still be
written to record the discover}- of new canals. But
the astronomer of the future will sneer at these
wonders ; and the canal fallacy, after retarding
progress for a third of a century, is doomed to be
relegated into the myths of the past.
STONYHURST COLLEGE OBSERVATORY.
By FRANK C. DENNETT.
The report of this useful observatory for the year 1912 has
just been issued by its Director, the Rev. Walter Sidgreaves, S.J .,
F.R.A.S. The mean barometric pressure for the year was -054
Tablk 39.
YIM K IV IT ir ir 10 S « 7 6 5 4 3 2 1
1896
1899
1900
1901
190?
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
•,
\
S
i
...i
,v
N.
•C"
S
>
>
<
«.;'
\
"x.
>
V.
<
•-.
'">
FCJ
I
Magnetic mean declination range.
Mean daily spot area.
inch below the average of the previous sixty-five years, and so
lower than 1911. Only in the months of April, September,
October and November was it above the month's average ;
September yielding the highest mean, and March the lowest
of the year. The rainfall was nearly seven and a quarter inches
above the annual average, for which the excessive rains in
March, June, August and November were largely responsible.
During March the fall was half an inch above double the
usual fall, being 7-205 inches, the greatest during the previous
sixty-five years. April proved the finest month, the only one
with the duration of sunshine above its average, and its rain-
fall little more than half its average. The total duration of
sunshine during the year was only 927-6 hours, or 409-6
hours short of the annual average, the smallest on record for
thirty-two years. The dullest months, March, June, August,
and December all yield the lowest number of shining hours
previously on record. The year, notwithstanding the small
amount of sunshine, proved a mild one, for though the
summer was below the average, the winter was above. The
mean temperature for the year was 47° -5, or 0:>-6 above the
average. Only on five days the wind attained the velocity of
a gale, the strongest being on April 6th and 8th, when the
record stood at forty-five and forty-six miles per hour.
Magnetic records appear to be missing on three days,
September 30th, November 18th and 19th. Of the rest,
one hundred and twenty-four days are recorded as calm, two
hundred and twenty small disturbance, eighteen moderate,
and only one, October 14th, as great, no very great dis-
turbances being recorded. The mean daily range of the
Declination magnet in arc minutes was 8'-l, the lowest of the
past eighteen years. The lowest monthly mean daily range,
6'-l, was in January. The mean area of sunspots (in units
of irnireth of the visible surface) appears at 0-22. Compared
with previous years, together with the magnetic declination
range in graphical form, it seems to show that 1912 marks the
minimum of sunspot activity. The diagram is constructed by
the writer from the Stonyhurst records since 1898, and is
perhaps more striking than figures. The spectrum of Nova2
Geminorum was photographed on seven occasions, besides
being observed visually on other nights. Gale's and Borelli's
comets were both photographed and observed, but not under
favourable conditions.
One sentence in the report we note: ' It has been decided
at the Meteorological Office to reduce the number of its
observing stations ; and our connection with the office ceases
at the end of March. But the automatic recorders are to
remain here, and will be kept in active service."
TRYPANOSOMES.
By MALCOLM EVAN MACGREGOR, E.R.M.S.
Considering the great amount of attention
trypanosomes have demanded, and are still de-
manding, in many tropical and semi - tropical
countries, it will he the endeavour in this paper
not so much to present a scientific or in any wax-
thorough description of
the organisms called
trypanosomes, but more
to give a brief survey of
a few of the aspects of
general interest that are
met with in their study.
Trypanosomes belong,
in the animal classifica-
tion, to the Phylum
Protozoa, and are
parasites in the blood of
vertebrate animals. They
are minute unicellular
organisms of somewhat
eel-like shape, and range
in length very widely:
from seven to thirty
microns being about the
commonest variation.
Eirst discovered in the
\ear 1841, by Valentin,
in the blood of a fish,
they have since been
found in the blood of
nearly all vertebrates, and
while some species of
trypanosomes do little,
if any, harm to the ani-
mal in whose blood they
live, and where they may
swarm; other species, if
present only in the
smallest numbers, pro-
duce most terrible results.
Such diseases, for
instance, as sleeping
sickness, Nagana (the
fly-sickness of cattle in
Africa), Dourine (a
horse - sickness in India
TT>t fW^tUunv
the blood of a trout ; but it was not until 1880 that
Evans, working in India discovered the first patho-
logical trypanosome. This was the trypanosome that
produced the disease in horses and camels, called
Surra. Eourteen years afterwards, in 1894, came
Bruce's discovery of a
trypanosome as the
cause of Nagana (or fly-
sickness) in Africa.
In 1901, Button dis-
covered a trypanosome in
the blood of a European
in the Gambia, which
he appears at first not to
have quite realised the
significance of. In the
May of 190.3, Castellani,
while examining the
cerebro-spinal fluid of a
native suffering from
sleeping sickness, dis-
covered in this fluid a
trypanosome, and it was
he who first connected
the organism with the
disease.
/acuc'its
From a Drawing by Count L. tie Sibottr
Figure 20.i. Trypanosoma gambiense.
The most salient structural details of a Trypanosome.
Morphology.
The Morphology is
extremely simple (see
Eigure 203). The body
consists of an elongated
mass of protoplasm taper-
ing anteriorly to a fine
point, and ending pos-
teriorly rather more
blu nth'. The body proto-
plasm is often very
granular, and often shows
vacuoles in it.
About the centre of the
body the structure known
as the nucleus is generally
situated, but oftentimes
it is found more anteriorly
Mai de Caderas, of placed, and at other times it is in quite a posterior
South America, a human disease that occurs in the position. In shape the nucleus is usually oval
same country, and many others, are all diseases or resembling the shape of a bean, and stains a
due to trypanosomes ; so that trypanosomes in dense purple-blue colour with the ordinary
some parts of the world have to be looked upon as trypanosome stains. The chief function of the
one of man's deadliest enemies: an enemy over nucleus is thought to be the governing of the
which, as we shall see later, he has yet been able functions of the protoplasm (the metabolism and
to get but the smallest victory. katabolism), and it is hence sometimes called the
It was, as already stated, Valentin in 1841 who " tropho-nucleus " to distinguish it from another
discovered the first trypanosome, and this he did in small mass of nuclear material that occurs in the
:: Being the subject-matter of a lecture delivered before the Cambridge Natural History Society, February 20th, 1913.
197
198
KNOWLEDGE.
May, 1913.
bord
ering
the
body of the organism, namely, the Micronucleus.
This occurs usually quite posteriorly in the
body, and it is thought that its function is to
govern the movements and reproduction phases, and
hence it is sometimes called the " kinetonucleus."
The "undu-
lating-mem-
brane " is a fin-
like ridge or fold
of the bod\' pro-
toplasm,and lies
to one side of
the body. Being
longer than the
body-length, as
will be seen in
the illustrations,
it is cast into
many wave-like
folds. It is a
very delicate
membrane of
very variable
width, being in
some trypano-
somes so narrow
that it is almost
impossible to
make out : at
other times it is
considerably
broader even
than the body-
width. It con-
stitutes an organ
for swimming.
From the mi-
cronucleus there
arises a thread
of nuclear ma-
terial called the
" fl age 1 1 u m,"
which runs for-
ward anteriorly
along the bodv,
Lony $ Slender.
extreme edge of
the undulating-
membrane, as
far as that goes,
and then pro-
ceeding beyond
the anterior end
as a free thread
or lash, called
the "free flagel-
lum." This may
extend to twice the body-length. Its purpose is also
for swimming.
Trypanosomes are essentially very " lively "
creatures, and most, while capable of swimming
actively in the blood by means of the undulating-
Short £ Stumpy.
By permission of The Tropical Disease.
Figure 204.
Trypanosoma gambiense X 2,000, showing types.
membrane, and free flagellum, are also capable of
wriggling and twisting movements. All the move-
ments in health)- trypanosomes are generally very
violent, and the blood corpuscles are thrown in all
directions as the organisms dart here and there.
The movement
of the undulat-
ing membrane
has been very
aptly compared
to tile flapping
of a boat's sail
that has " lost
the wind." It is
an exceedingly
graceful move-
ment, and
travels as a rip-
pling wave over
the entire mem-
brane. The
direction of the
waves vary ac-
cording as to
whether the
animal travels
backwards or
forwards. The
movements of
the flagellum
are almost im-
possible to make
out as only their
effects on the
surrounding
medium give
one any indi-
cation of what
they are ; but
the\- must
obviously be
some systema-
tic series if
they are to
benefit progres-
sion. It is due
to the rapidity
of the move-
ments of try-
panosomes, that
trypanosomes,
while they are
living, are such
extremely diffi-
cult subjects to
study. In the
case of T. vivax,
a particularly lively creature, all that can be seen in
the medium in which it exists are rocket-like
paths as the trypanosome dashes across the field of
the microscope.
Trypanosomes multiply in the blood of their hosts
After a plate by Lady
Bruce (Royal Society Proc. B. vol. 84.)
May, 1913.
KNOWLEDGE.
199
by longitudinal fission.
The micronucleus is first
seen to divide into two,
splitting, as it does so, the
flagellum into half, so
that each of the two new
micronuclei has a strand
of the flagellum attached
to them. The splitting of
the flagellum then pro-
ceeds through the whole
length, the nucleus divides
into two, and by fission
in the protoplasm, the
organism becomes two
separate individuals, usually
of unequal size. The re-
production phase probably
has a far more compli-
cated cycle than this, how-
ever, even when repro-
duction in the blood of the
host is only considered, to
which the above descrip-
tion refers: but beyond this fission-method
of reproduction nothing is yet sufficiently
definitely known to need mention here. In
the alimentary canal and salivary glands
of the tsetse-fly, the reproduction phase of
trvpanosomes is exceedingly complex.
The remarkable diversity in size and
shape that is found in trypanosomes of
any one species living in
the blood of an animal is
striking. They may vary
from slender organisms of
great length, possessing
highly developed undulat-
ing membranes, and long
free flagella, to quite
short, stumpy organisms
entirely wanting both these
appendages. What the
complete significance of
this series is we are at
present unable to say,
but some are probably
younger individuals, and
it seems likely that the
stumpy type are of a more
resistant kind than the
long type, since it is they
that are most numerous in
the blood when the host
is fighting the disease, or
when drugs are given to
the animal that render its
blood unfavourable to
the development of the
By permission of Professor Mincliin and The Cambridge University Press.
Figure 205.
Trypanosoma gambiense from blood of rat. X 1,000.
(Smear fixed out with osmic acid vapour, and stained by C-iemsen. A slender,
astumpy, and an intermediate form are seen. From plate illustrating Professor
Minchin's paper in Parasitology, I. No. 3.
*
' " mi 1 1 1 1 , 1 1 1
Natural size.
1 11111 iiuniiii 11 1 in
Magnified 13 diameters.
liy permission o/ The Tropical Diseases Bureau,
Figure 206.
Glossina palpalis Rob-Desv. The tsetse fly
A good representation of the resting fly, but in life the palpi would 1
Fi
appressed and light would not be visible between them From a photo
graph by I)r. W. M. Graham, Director of the Medical Research Institute.
I.agos, S. Nigeria.
trypanosome. Figures 204
and 205 show various types
of the same organism.
Distribution.
Trypanosomes occur all
over the world, and those
found infecting wild
animals in nature, are, as a
rule, quite specific to a par-
ticular host, and so far as
can be observed, perfectly
harmless to it, but there
are some which infect
man and animals, and are
highly pathogenic. Such, for
instance, is Trypanosoma
gambiense, the parasite
that produces Sleeping
Sickness. It is pathogenic
to all animals as well as
man. T. brucei, the try-
panosome that is so deadly
to the cattle and domestic
animals in Africa, gives rise to the disease
called Nagana or Fly-sickness; but it is
harmless to man, for it is unable to exist
in his blood.* An example of a trypano-
some that is harmless to its host is to
be found in T. lewisi. This trypanosome
is quite specific to rats, and though it may
swarm in the blood, so far as can be
seen, it has no harmful
effect on them, and as soon
as the infection has reached
a certain stage the number
of trypanosomes steadily
decreases in the blood,
finally disappearing alto-
gether, and leaving the rat
quite immune to a second
infection.
A marked contrast to
this state of affairs is found
in the case of the trypano-
some of sleeping sickness.
Here, at no time in the
course of the disease in man
and many animals, are
the trypanosomes ever very
numerous, and though
their deadly effect may
be highly manifest in the
infected animal, their
presence in the blood
may be exceedingly diffi-
cult to detect, owing to
the extreme scarcity of
the parasites.
* Since the above was written it has been stated, positively, that the cases of sleeping sickness in Nyasaland are due, not to a specific trypanosome called '/'. rhotUsiense.
but that this trypanosome ('/'. rliodesiense) turns out to be none other than T. brucei, i.e., the parasite that produces Nagana. (See paper by Sir I). Bruce and others, Royal
Society's Proceedings, Biological Section, April 7th, 1913). This shows how indefinite much of our knowledge of these organisms still is. For all there is to the contrary,
we may very well find ere long, that one half of what are looked upon as distinct species, are one and the same organism, altered slightly, it may be, by its adaptation to
different environments.
200
KNOWLEDGE.
May, 1913.
Trypanosomes depend for their transmission from
one animal to another, with very few exceptions, on
the agency of blood-sucking invertebrates, which we
may call "the carriers."
Thus the trypanosomes of fishes are transmitted by
leeches from one fish to another ; the trypanosomes
of rats, bv the rat-flea ; the human trypanosome
(T. cruzi) of South America, by a hemipterous
insect ; the trypanosome of sleeping sickness and
the cattle disease of Africa, by a blood-sucking fly
of the genus Glossina ; and so on.
The trypanosomes having entered the alimentary
tract of the carrier in a meal of blood from an
infected animal, there undergo a developmental cycle,
and it seems most probable that not until this cycle
is complete are they able to infect other animals,
when the blood-sucking fly or carrier feeds. They
enter the blood stream of the new host in the
secretion the fly pours out through its proboscis
preparatory to commencing its meal.
Distributing Factors.
Glossina palpalis, (see Figure 206) the carrier of
sleeping sickness, is a fly not unlike a common house
fly in appearance, though it has a proboscis for
piercing the skin of animals in place of the house-
fly's suctorial pad, or so-called tongue. There are
fifteen different species of Glossina already known,
but only two or three of these species can be
incriminated in spreading disease, as it has been
found that only particular species can act as carriers
of trypanosomes. All the flies of this genus, except
for minor differences in the species, have much the
same life-habits, so that a description of one will
more or less apply to all. We will deal with palpalis.
This fly, like several species of tsetse flies, lives
near the banks of rivers or lakes, and is found,
fortunately, in only a comparatively small area
of Africa's vast extent. The fly is not naturally
infected, but has first to partake of a meal of
infected blood before it becomes so. It then, only
is capable of infecting people, when it bites
them, after a certain interval has elapsed— a
few hours — and the period while it is capable
of infecting people lasts only for a certain
number of days. To become reinfective the fly
must again feed on infected blood. Both sexes suck
blood, and it is in the early morning and at sun-
down that the}' are most vigorous in this pursuit.
Rarely they feed at night-time, when the moon is
bright. The fly having settled and pierced the skin
of its victim, can become gorged with blood in from
twenty to thirty seconds. The bite is hardly more
painful than that of a mosquito or gnat, and
there is a similar slight swelling at the site of the
bite. The name " tsetse " is a Zulu word, and is
supposed to describe the peculiar high-pitched
buzzing of the insect's wings in flight, as it passes
within one's range of hearing.
It has been calculated that the number of flies
that are infected at any one time is small, and so a
bite from one does not necessarily mean to contract
sleeping sickness ; but the fearful havoc that even
this small percentage can work will be understood
when it is said that between 1901-1912 in Uganda
alone, a very low estimate of the number of victims
is about one hundred and fifty thousand to two
hundred thousand people. Whole tribes of natives
have in some cases been exterminated.
The flies do not lay eggs, but produce their young,
one at a time, in the pupa stage. These they
deposit in the dry sand below the undergrowth on
the bank of watercourses, and the pupae, burrow-
ing their way a few inches below the surface, there
undergo a metamorphosis, and ultimately emerge as
fully developed flies. This metamorphosis is com-
pleted in about six weeks.
These are quite healthy, and as already said,
cannot cause disease by their bites until they have
fed on the blood of an infected animal. Therefore,
the question naturally arises, "Where is the reservoir
of the disease by which these flies become infected ? "
That question cannot unfortunately be quite satis-
factorily answered at present. The big game of
those parts have been blamed, and although it
has not been definitely shown yet that they are
responsible, evidence is every day accumulating
against them.
It was at first thought that the crocodile was the
reservoir, as palpalis was known to feed on them,
and in their blood was very commonly found a
trypanosome very similar to T. gambiense, and
which was at first mistaken for it. But it has now
been proved to be a different parasite.
(To be continued.)
NOTICES.
"LIQUID AIR OXYGEN NITROGEN."— Messrs. J. and
A. Churchill announce that they are about to issue a transla-
tion of this book, which is by Mr. Georges Claude. It will be
of particular importance to Agriculturists in this country, as
considerable attention is devoted to Nitrogen.
CATALOGUES.- — We have received Mr. John Wheldon's
Entomological Catalogue which contains the titles of about
fourteen hundred books and papers dealing with all orders of
Insects, together with Spiders and Myriapods.
Mr. Charles Baker's classified list of second-hand instru-
ments for April, 1913, is before us, and should prove as
useful as any of its predecessors.
MISS FLORA WIN STONE.— We very much regret to
hear that Miss Flora Winstone, for many years assistant
editor of Hardwickc's Science Gossip, died on the 22nd
March at South Norwood.
PHOTO-MICROGRAPHY.— We would remind our readers
that the demonstrations on this subject which Mr. Senior is to
give begin on Monday, May 5th, at the South Western
Polytechnic,
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
JUNE, 1913.
PROBLEMS OF PLANT LIFE.
1. EVOLUTION AMONG LOWLY FORMS (THE ALGAE).
By S. REGINALD PRICE, B.A. (Cantab.).
Ever since the publication of Darwin's great work,
one of the chief aims of the biologist, in studying
organic nature, has been the establishment of a
scheme indicating the real evolutionary relationships
of forms, or, to use the more stereotyped expression,
a natural system of classification.
In the plant kingdom certain lines and tendencies
within the great groups have been established with a
high degree of probability, chiefly from evidence of
comparative development, of reproductive structure,
and of the fossil record. Of the origin of the great
groups themselves, theories and speculations have
been numerous ; but they are nothing more than
bare possibilities, and, perhaps, hardly that in some
cases. If, as seems rather probable, all plants
evolved from a common stock, the divergence took
place countless ages ago, but the voice of the rocks
is silent on this question.
Assuming, however, such a common group, it is
almost certain that its members were aquatic, and so
it seems reasonable to expect that the more primitive
members of our existing flora will be found in such
an environment. All the evidence goes to show that
the Algae as a group — comprising plants almost as
simple as may be imagined as well as the quite
complex bodies of the higher seaweeds — have never
lost their aquatic habit, and so, presumably, the
group as a whole has not suffered that great change
in the course of evolution which must have accom-
panied the adoption of the terrestrial mode of life.
It has, therefore, been interesting to examine this
group carefully, with a view to throwing some light
on the evolution of plant-forms within it, and thus
indirectly obtaining a dim and indistinct reflection
of the process of elaboration of the "Proto-plants."
The evidence has been confined to the study of
existing species alone, for the few fossil Algae, often
of very doubtful identity, are quite useless as indica-
tions of the phylogeny of the group. When, there-
fore, an evolutionary line is spoken of in this
connection, it must be remembered that it represents
a series of related species, not necessarily and most
often probably not directly related in a single line of
descent, but nevertheless giving an indication of the
tendency which has led to the elaboration of the
various forms. Exactly what is meant may be
illustrated by considering several obviously related
forms, which may be indicated by the letters
A to G, the last being presumed to possess the
most complex organisation of the series. Without
considering the factors at work, there is reason to
suppose that the form A has retained more primitive
features and undergone less alteration than B, and
so for each succeeding form, the climax of the series
being represented by G. The diagram (Figure 208)
represents this in a crude manner ; the lines running
from left to right indicate progressive evolutionary
tendencies, while those running vertically indicate
201
202
KNOWLEDGE.
June, 1913.
branches from the stock, which have undergone
comparatively little modification, and which
terminate in living species. The real direct line is
from P, the primitive type, to G, while the so-called
evolutionary series is represented by the forms
A to G. The conception must usually be under-
stood in this sense, and the Volvox line con-
sidered below may be cited as a concrete example.
Collective evidence has shown that the main lines
of progressive evolution in the Algae have probably
diverged from a group represented to-day by the
Flagellata, a complex of minute organisms lying on
the border line between the animal and vegetable
kingdoms. These Flagellates, as their name indicates,
are ciliated free-swimming " creatures," often sapro-
phytic in their mode of life, of which some members
are colourless, some possess chlorophyll alone as a
pigment, while others are coloured yellow, brown or
red by substances closely allied to or often, perhaps,
identical with those present in the brown and red
sea-weeds. There is no need to consider these
organisms further here.
Those forms, which are unicellular and motile
throughout the greater part of their life-history, seem
to illustrate the types of Algae which are nearest to
the primitive forms and to their hypothetical pro-
genitors, the Flagellata. Considering for the present
the green Algae or Chlorophyceae alone, such forms
are found in the order Chlamydomonadaceae (of
which the genus Spluwrella is a well-known type),
and various authors have taken the genus Chlamydo-
monas as a primitive type, and have outlined systems
of classification indicating the probable lines of
evolution from this.
Chlamydoinonas, or the common pool-alga Sphae-
relhz, which is very similar, is unicellular, with a
yrtt-yt
single nucleus and chloroplast, and possesses two
fine protoplasmic cilia attached to a small beak-like
projection at the anterior end of the cell. It is
motile by means of these cilia throughout the
greater part of its life-history. Reproduction takes
place by simple fission of the cell contents, or by
conjugation of gametes. Under unfavourable con-
ditions, the cells may go into a non-motile resting
condition.
Starting from such Chlamydoinonas forms, three
main series may be recognised among the lowlier
Algae leading to the establishment of three distinct
A
»*>
3
Figure 207. Some forms of Volvox Line. Diagrammatic,
a. Chlamydoinonas. b. Goniutn.
c. Pandorina.
d. Pleodorina.
£>--:_<:' •---«L
Figure 208. Diagram illustrating the evolution of
forms.
types of thallus : one to the formation of colonial
bodies, one to the filamentous and plate-like
forms, and the third to the so-called siphoneous or
coenocytic type of plant body. The organisation of
these various types of plant body will be more fully
described when we consider the several lines in
detail.
The Volvocineae comprises a series of genera and
species which have long been recognised as closely
related, and they seem to illustrate well the stages
which have probably led to the development of a
free-swimming colony. In Gonium there is an
association of four or sixteen cells, each like
Chlamydomonas provided with two cilia, the whole
colony being in the form of a flat square (see
Figure 207, b). There is a non-motile resting period
when asexual reproduction takes place — simply by
the division of each cell to form a new colony.
Pandorina is slightly more complex ; there are six-
teen cells arranged in the form of a closely packed
sphere. The cells are all alike, each with its two
cilia, and any cell of the plant can divide
to produce a new colony or coenobium as it is called.
Pleodorina has the cells at one end wholly vegetative
and smaller than the rest — the first real indication of
the structural unity of state — and the sterile cells
represent an incipient vegetative body or " soma "
as opposed to the portion concerned in reproduction
alone (see Figure 207, d). Pandorina is quite
common in freshwater pools and ditches in this
country, but Pleodorina does not seem to occur.
The culminating type of the line is Volvox, well
known to all microscopists. The colonies here
consist of several thousand cells arranged in the
form of a hollow sphere, and there is a definite
sterile pole. There is a fairly high type of
sexual reproduction besides the asexual method by
division of the parthenogonidia. The unit}' of the
whole colony is still more pronounced than in the
June, 1913.
KNOWLEDGE.
203
other types, for the cells are in connection with one
another by means of tine protoplasmic threads,
which connecting threads have not been detected
in other colonial forms of this group. These
genera may be arranged in a series as shown in the
diagram (see Figure 209). The evolutionary
7&x(/or~t ntz
Cf&f-ycfontona.s
/Veodorina
Figure 209.
Vain
Possible scheme of Evolution of
Volvox Line.
d. Ulothrix.
tendency represented by the base line may thus be
read as one leading to the association of motile cells
to form a free-swimming colony, and to the
elaboration and differentiation of the coenobium.
It appears that this line has led no further than to
Volvox, possibly owing to the instability of the large
body of loosely connected
cells.
The manner of deriva-
tion of the filamentous
and thalloid types is by
no means so clearly indi-
cated by living forms, but
still a line can be traced
with a fair degree of
possibility through the
Tetrasporaceae. Essen-
tially, the filament is a
segmented tube, each
compartment representing
a single uni-nucleate cell.
Manyof the simpler forms,
Ulothrix, for example,
produce zoospores which are substantially of the
Chlamydomonas type, indications of the retention
of primitiveness in the reproductive condition.
Evidently if these filaments and plates have been so
evolved, there took place an increase in the length of
the resting periods, and an association of the resting
cells to form a chain or fiat plate. A few examples
from the Tetrasporaceae will show that there is
certainly some evidence for such a process.
In Chlorangiuin the swarm-spores attach them-
selves, develop a short stalk, and divide to form
tree-like growths of which an)- one cell may detach
itself and act as a bi-ciliate swarmer. The signifi-
cance of this genus is rather the marked non-motile
stage in the life-history. In Hormotila the spherical
cells are enclosed in cylinders of mucilage, and the
whole association shows some approach to the
filamentous condition. Each cell can produce
zoospores by division. Radiofilum is still nearer to
the filamentous condition (see Figure 210, c). None
of these genera is at all common. On the other
hand Tetraspora, a somewhat common alga, builds
gelatinous aggregations of indefinite shape, the
Figure 210. Some types of Ulothrix and Ulva Line,
a. Chlorangium. b. Hormotila. c. Radiofilum.
spherical cells being arranged in groups of four in
the mucilage. Monostroma is somewhat similar, but
forms a definite plate one cell thick, and on account
of its thalloid type of body is generally placed in the
Ulvales. These two lead to the genus Ulva, a
common green seaweed, where the thallus is quite
definitely two-layered and more highly differentiated.
A general tentative scheme for the evolution of
simple filamentous and plate-like forms is shown
diagrammatically in Figure 211.
From the simple Ulothrix type a series showing
various higher degrees of differentiation may be
traced in the plexus of orders called the Ulo-
trichales, but the consideration of these would lead
us into a mass of details rather to be avoided in
a purely general outline.
The third main line has probably led to the so-
called coenocytic type of thallus, where the plant
body is unseptate or nearly so, but each " cell " thus
formed is multi-nucleate. The living forms in the
Chlorococcineae, none of which is very generally
known, however, seem to lie near the root of the
siphoneous type. With-
out going into detail, then,
it may be said that
Pediastrum (a common
moorland alga) and
Hydrodictyon (the beau-
tiful, but rare, " water-
net ") are really colonies
of many multi - nucleate
" cells." Protosiphon is
obviously a fairly primi-
tive member of the
Siphonales, possessing a
hollow, sac-like coenocytic
body. The more highly
differentiated members of
this group will not be
considered, but it may be interesting to note that
many of them, like Caiderpa or Acetabularia, are
beautiful forms inhabiting the warmer seas.
It is obvious that our present flora must represent
very many lines of descent, which have branched
ULOTRICHALCS
V/of-An?
e. Tetraspora. f. Monostroma.
7&ufroA/t<m
Ho
af'aa
Tef-rotpora
ULVALE0
„> Monoftroma-
CAloranocufn
\
Ch la *»ydo i*\o«a<(
Ancestor
Figure 211.
Possible scheme for Ulothrix and
Ulva Line.
204
KNOWLEDGE.
June, 1913.
into new lines over and over again. The well-worn
simile of the tree and its branches will once more
serve to illustrate this. The "tree of the Green Algae "
has its trunk represented by the main line of evolution
from the Flagellata, and then it may be supposed to
branch into three — thethree lines which have been con-
sidered. The Volvocine branch is probably short and
with little ramification ; the others fork repeatedly,
producing finer and finer branches and twigs. The
leaves of the tree alone represent existing forms, but
here the simile rather breaks down ; for it must be
supposed that the leaves nearer the top of the tree
are more highly evolved than those lower down.
The trunk and branches are obscured in the mists of
the past, and our problem is to indicate these from
a knowledge of the leaves alone. The postulated
arrangement of the leaves must give considerable
help, but the impossibility of complete solution is
patent.
It must be remembered that not one of these
proposed modifications in evolution has actually been
observed to take place, and the position and basis
of the scheme are theoretical. It is quite impossible
to dogmatise on any problem of evolution, at least
in the present state of our knowledge, and different
schools of thought may read quite a different inter-
pretation into the facts.
The forms which have been considered here are
all characterised by the bi-ciliate type of zoospore or
gamete, with equal cilia, when any are produced, and
this has been thought of sufficient importance to
mark off the group, which has been called the
Isokontae by Blackman and Tansley. Space does
not permit of the discussion of the other groups, but
there is evidence that the " coloured seaweeds " have
been evolved directly from coloured Flagellates,
while the Oedogouium forms and the Conjugatae,
including the Desmids, and so on, may have sprung
from the Isokontan stock.
It is impossible to doubt the great fact of pro-
gressive evolution when confronted with this and
similar series of organic types. Most of the great
underlying principles and laws of the process are
still to be elucidated, however. The Algae appear
to be still plastic, and further study and observation
should at least help us to grasp some of the forces
and influences which are at work in the production
of a new species in the world flora.
ELECTRICAL CONDUCTIVITY IN THE SERVICE OF BACTERIOLOGY.
By DR. ALFRED GRADENWITZ.
Interesting experiments have recently been made by Dr.
M. Oker-Blom, Professor at Helsingfors University, on the
possibility of utilising the electrical conductivity of bacteria
cultures for obtaining useful data on the nature of bacteria
and the biological phenomena occurring in these cultures."'
The electrical conductivity of an electrolyte is known to be
reduced by the presence of non-conductive substances such as
sugar, albumen, and so on, the more so as the amount of these
substances is greater. This reduction of conductivity has
further been shown to depend on the nature both of the
electrolyte and the non-electrolyte, being accounted for by
some sort of friction between the ions and non-conductive
molecules. If, now, a culture solution containing albumen or
sugar, or both of these, be submitted to such conditions that
these substances will undergo chemical scission, the con-
ductivity of the system is bound to be influenced in some
way or other. On one hand, the conductivity of the culture
liquid is increased by reducing through chemical scission the
amount of non-conductive substance ; if, however, the sub-
stances newly formed should likewise be non-electrolytes, the
total amount of non-conductive substance in the solution will,
as a matter of fact, be increased, and variable effects will be
observed according to circumstance. Far more marked effects
are, however, obtained whenever new electrolytes are produced
in the liquid, and as acids and alkalis are the most highly con-
ductive of these, any variation in the acidity or alkalinity of a
culture liquid as produced by bacterial influences is bound to
manifest itself in the conductivity of the liquid.
Dr. Oker-Blom has made three parallel series of experi-
ments comparing the respective influences of two bacteria
(Bacterium coli and Bacterium typhi) on the electrical
conductivity of culture liquids. The glass vessels used in
this connection had been specially constructed on his sugges-
tions, and contained strictly equal amounts of liquid. After
their inlet and outlet openings had been stopped with small
pads of wadding, they were introduced into a water thermostat,
maintaining them at any constant temperature desired, where
the electrical conductibility of the liquid could be watched at
any moment.
The curves reproduced in the original memoir give an
excellent idea of the behaviour shown by the conductivity of
culture liquids under the influence of the two bacteria. In
the first series the conductivity curve of the coli bacteria is
found to rise considerably already after two days, and even
more rapidly on the third and fourth days, in order afterwards
only to rise by degrees somewhat further. The conductivity
curve of typlii bacteria shows a quite different behaviour.
After exhibiting, during the first five days, only a slight tendency
to rise, it will rise abruptly on the fifth day, and continue
rising in a marked degree from the seventh to the tenth day.
After a slight further rise, it eventually approaches towards
the coli curve, though not reaching it entirely during an
eighteen days' experiment. The two curves show between
the second and the fifth day the greatest mutual departures.
The liquid used in this connection was Fraenkel's culture
liquid, with a slight addition of soda. The two other series of
experiments, made with the same liquid, containing one per
cent, of lactose and glucose respectively, gave quite similar
results. During the first two days a very satisfactory agree-
ment between the curves of conductivity and those of acidity
or alkalinity was noted.
These experiments go to show that the bacteriological
variations in the electrical conductivity of culture liquids are
really determined by products of chemical scission (neutral,
alkaline or acid). Though, being only the collective expression
of bacterial decomposition, the electrical conductivity thus
gives a fairly good idea of the actual phenomena, and as the
conductivity curves for each kind of bacteria show some
specific features, they might prove useful in detecting these
bacteria for the purposes of diagnosis.
Centralblatt f. Bakt., etc., I., Numbers 4-5, 1912.
WHY ARE WE RIGHT-HANDED?
AN UNBIASED BIOLOGICAL ENQUIRY.
By LEOPOLD KATSCHER.
All the more important manual actions are accom-
plished by the right hand rather than the left. It is
the right hand that is used to hold the sword, tool
or pen, the right that shakes hands with another,
that gesticulates, gives the sign of blessing, takes
part in various ceremonies, and so on. The place of
honour is conceded to the right hand. In German
and French an awkward person is termed " linkisch "
and "gauche" respectively. In several other lan-
guages " clumsiness " is synonymous with " left-
handedness." The English word "sinister" comes
from the Latin for " left-handed."
Shortly before his death Thomas Carlyle wrote :
" What extraordinary preference is given to the
right hand by all mankind ! It is probably a matter
of the very oldest human organisation. I wonder
whether a people exists that makes no difference
between the two hands. . . . Why just the right
hand should be chosen is an unanswerable question
not worth asking, unless it is to be treated as a
conundrum. Probably the matter originated in
fighting habits, for the left hand shields the heart
and surrounding parts better, and is the more suited
to carry the shield."
What was considered as inexplicable by the sage
of Chelsea later investigators have regarded as well
worth research. This is particularly the case with
Sir Daniel Wilson, who also offers a plausible
explanation in his work on left-handedness, in which
theoretical investigation is combined with practical
observation, for he was himself left-handed.
It is a fact that many people are left-handed —
how does this arise ? Is the general use of the
right hand alone a rooted, inherited consequence of
a primeval habit of mankind ? Or is it to be
attributed to natural and, therefore, more or less
immutable causes of a physical and constitutional
nature ? To become clear on the subject, investi-
gation must first be made as to the degree in which
right-handedness prevailed in the past and does
prevail in the present, and whether there was a time
when both hands were used indifferently, or whether
this has never been the case at all. The celebrated
novelist, Charles Reade, who was able to use both
hands with the same skill, and justly urged the
training of children to practical ambidexterity,
declared himself for the first hypothesis (that in
former times no difference was made) in his
" Coming Man " (1882), and asserted that there are
still savage tribes among which no preference is
shown for any one hand. If such is the case, the
preference would be the result of an artificial habit
acquired later. A recent investigator, Dr. Ernst
Weber, also expresses his conviction that there was
a time when men used both arms indifferently. At
that time, those who happened to choose the right
arm for fighting had the advantage of shielding their
hearts as they pushed forward with the right side
foremost. "Thus more left-handed than right-handed
men perished before begetting progeny, and the
right-handed were, therefore, more often able to
transmit their habit of fighting with the right, and
so their numbers increased," while the left-handed,
who became ever fewer, endeavoured to overcome
their pernicious habit till right-handedness became
all but general. Dr. Manfred Frankel believes this
theory to be in accord with fact, as it may be
concluded from the statues that have come down to
us, that in the Stone Age there were many more left-
handed people than there are now. He adds :
" What happened in the fight may soon have been
retained in all other manipulations. Practical
deliberation caused them to pursue the course of
development once begun, and so right-handedness
was transmitted by heredity, and superinduced by
habit and training to a definite characteristic of
■humanity."
This hypothesis is not without deficiencies and,
therefore, not altogether satisfactory. Sir Daniel
Wilson, who devoted many years of study to the
subject, has come to quite a different conclusion
founded upon archaeological, palaeontological, philo-
sophical, geological and historical researches. As
regards the prehistoric cave-dwellers of the Stone
Age, Sir Daniel has most carefully examined their
flint implements and has come to the conclusion
that they were right-handed with rare exceptions.
He makes the same inference from the many refer-
ences in all the known oldest and most primitive
languages, as well as ancient writings. The fact
that several oriental languages, including Hebrew,
are not written from left to right, but in the opposite
direction, might at first sight argue for left-handed-
ness, but a closer examination contradicts the
supposition. These writings are not continuous,
they are separated, so that it is perfectly natural
that they should be written with the right hand. A
superficial inspection of some of the old Egyptian
monuments leads to an inference of left-handedness,
but a thorough study reveals this to be wrong.
Although in drawing the profile of a face a right-
handed artist would depict the left side as a matter
of course, and many Egyptian reliefs present faces
turned to the right, the reason is not to be found in
205
206
KNOWLEDGE.
June, 1913.
the possible left-handedness of the sculptors in
question, but in deference to architectonic effect.
Even when a figure is represented holding a pen or
a sword with the left hand, it is only as an exception
which is to be traced back to considerations of
symmetry and perspective. Where such considera-
tions are not necessary, preference is always given
to the right hand. With regard to the monuments
of Central America testifying to a long vanished
civilisation, it is to be noted that the stone, figures
mostly face towards the left and will have been
chiselled, therefore, by right-handed artists.
Separate designations, in different languages, of
the quarters of the heavens also speak for the age
and generality of right-handedness. Thus, for
instance, the Hebrew word "jamin" signifies both
" south " and " right hand." The same is the case
with the Sanscrit " dakschina," derivations of which
are to be found in most Indo-European languages,
and the like is to be met with elsewhere as well.
These double meanings originate in the fact that the
peoples in question took their bearings from the
position of the rising sun, and the south was, of
course, on their right. Sir Daniel infers from all
this that right-handedness is no chance or mere
habit, but is based on our physical and mental con-
stitution. The fact, therefore, that door-hinges and
handles, the spirals of a corkscrew, the adjustment
of scissors, and hundreds of other objects are all
calculated upon right-handedness rests upon valid
reasons. This deduction that there must be some
physical reason caused Sir D. Wilson to endeavour
to discover its nature. There is a great variety of
opinion on this point. The celebrated anatomist,
Barclay, for instance, a few decades ago, expressed it
as his opinion that the flow of blood was less as to
quantity and less regular on the left side than on
the right ; but Professor Buchanan, of Glasgow
University, maintained the theory that right-
handedness depends upon mechanical laws in
connection with the build and position of the
intestines ; thus the right lung has three lobes and
the left only two, and the liver, the heaviest organ
of the body, also lies on the right. Dr. Struthers
endeavours to strengthen Prof. Buchanan's theory
by asserting that the intestines to the right of the
median vein weigh twenty-two and three-quarter
ounces mere than those on the left. But the above-
mentioned scholars acknowledge, and acknowledge
respectively, that their theory is not able to account
for all the phenomena connected therewith. Sir D.
Wilson admits that the arrangement of the intestines
exercises some influence, but he seeks the chief
reason elsewhere — in the relationship between the
hands and the brain. As is well known, the two
cerebral hemispheres are the centres of the nervous
and muscular force in a contrary sense, the left
hemisphere governing the right side of the body and
the right hemisphere the left side. " Now the
left part of the brain is larger and has more convolu-
tions than the right, and it also receives a more
direct flow of blood." * In forty brains Broca found
the left frontal lobe to be heavier than the right ;
and Boyd met with the same result in the examina-
tion of five hundred brains. It would thus follow
that in cases of left-handedness the right side of the
brain would, by way of exception, be heavier than
the left. Wilson naturally sought an opportunity
for a practical test of this conclusion. After several
years of expectation, the opportunity was offered by
the death of an incorrigibly left-handed soldier in
Toronto. In weighing the brain it was then found
that the right hemisphere really was heavier than
the left.
A rather queer theory has been advanced by Dr.
F. Rosenberger. He connects the predominance of
the right hand with the apparent movements of the
stars, the need of taking orientation bearings in
space, and the consequent necessity for an artificial
division of the body into two asymmetrical halves,
the left one negative and the right positive, as well
as with the fact that an inhabitant of the higher
latitudes of the Northern Hemisphere, standing with
his face to the sun to take his bearings, can follow
the sun's course across the sky better with the out-
stretched right arm than with the left. Leaving
other improbabilities out of the question, Dr.
Rosenberger's hypothesis must be wrong from the
mere fact that the right-handedness of the inhabit-
ants of the Northern Hemisphere would then
necessitate the prevalence of left-handedness among
the dwellers in the Southern, which, however, is not
in the least the case.
An attempt at an explanation made anonymously
in the Paris Nature is no happier. It maintains
that mothers more often present the better-developed
right breast to their infants, whose right arm is thus
less cramped and more able to make frequent
spontaneous movements, so that it strengthens
sooner than the left. Text-books on anatomy make
no mention of it, and personal information gathered
from experts partly denied it and partly maintained
the reverse. Nor can the hypothesis be proved that
children are more often carried on the right arm
than on the left.
Other investigators assign the reason for right-
handedness to the asymmetrical position of the
heart and point out that owing to the construction
of the aorta the right side of the body has a stronger
supply of blood than the left, and that the right
arm thus has a distinct advantage through the
better nourishment of the muscles. The very
structure of the heart would, therefore, enforce
right-handedness. This, however, is not valid.
Apart from the fact that it has been proved
practically that it is not difficult fully to develop the
left hand, there exist animals, such as the gorilla,
chimpanzee, and seal, with a like anatomical structure
revealing no trace of a preference for one side or the
other. " In fact, it would be absolutely impossible
for birds to fly," remarks Dr. Stekel, rightly, "if they
were constructed so as to be right-winged."
:: This is contradicted by many anatomists of our own day.
June, 1913.
KNOWLEDGE.
207
According to Bolk, right-handedness is connected
with " the better nourishment of the left cerebral
hemisphere which is the nerve centre for the right
half of the body." According to Biervliet, " the
nervous system also participates in asymmetry."
Professor Buschan wrote in 1902 : — " In a large
majority of cases the right side of adult bodies is
the more fully developed, with the exception of the
left leg. . . . The activity of the nervous system is
always greater on the more fully developed side. If
the right ear is the stronger it never happens that
the left eye sees best. One is born either right-
handed or left-handed, and it is impossible to train
a left-handed person to be right-handed, or the other
way about."
Other investigators deny that it is " inborn " and
it is also frequently asserted that left-handedness can
be overcome. Among the numerous right- and left-
handed persons examined by two German doctors,
Langstein and Hecht, there was a young soldier who
was originally left-handed, and had overcome the
habit of chiefly using his left hand, although wjth
difficulty, when learning his trade, and afterwards
during his military service, and for years he had
worked easily with his right. Yet, whenever he was
in need of special dexterity he made use of the left.
It seems possible to get rid of left-handedness, not
alone by habit, but also by hypnotic suggestion.
Such an experiment was made by a doctor on a left-
handed child of four. The child's right hand was
held when she was in a hypnotic state, and she was
told to make more use of it in the future. The
effect of the suggestion was surprising, for the gjrl
began to use her right hand more from that time,
and after the third treatment given in the course of
a few days, she became right-handed, and has
remained so. The report in the Wiener Klinische
Wochenschrift reads : — " Quite apart from its
therapeutic success this case is of peculiar
interest because the effect of suggestion upon left-
handedness seems to establish that even when
left-handedness is developed in childhood, already
the two cerebral hemispheres may have originally
had equal capacities. The case not only argues
against the theory that the superiority of the right
half of the brain is the cause of left-handedness, but
maintains that it must certainly be possible to
prevent left-handedness through early training."
The following extracts, published anonymously in
the Frankfurter Zeitung, are worth noticing. They
recall the conjectures of Carlyle and Weber
mentioned above. " The preponderance of the
right hand is not a primeval gift, but an achieve-
ment of civilisation, an outcome of the progressive
corporeal and mental differentiation and division of
work. When man became man, when the build of
his body enabled and compelled him to walk
upright, the right and left hands must have been of
equal importance to him. While the legs and feet,
as organs of locomotion, still preserve equal rights
and duties, the activity of the arms and hands,
which was destined to a fuller development, was
distributed in such a way that the left hand plays a
passive, holding and shielding part, and the right
hand an active, seizing and attacking one. The
preponderance of the right hand must have been a
secondary phenomenon in the first instance. Combat
was at that time the principal thing — primeval
instinct was a surer guide in orientation than the
observation of the stars — and the need in combat
with man and beast to shield the most vital part of
the body, the heart, with the armed or unarmed left
necessitated that the club, axe, knife or spear should
be held in the right. This habit was carried into
peaceful pursuits. Since the day of primeval man-
hood, even after the original cause had ceased to
exist, the preponderance of the right hand was
developed and established more and more in
civilised nations through heredity and education.
This differentiation is even to-day less marked in
some primitive races, and there is also to some
extent less distinction made between the upper
and lower limbs (prehensile foot). Our children
are in a similar position, and must, in fact, be
educated to the use and conventional higher appre-
ciation of the right hand. Thus the greater skill of
the right hand is occasioned by the structure of the
human body, the position of the heart, and perhaps
the nature of the aorta, together with man's relation
to the outer world and the primitive cause for a
stronger development of the right arm, to which
factors of civilisation have been added."
Dr. Andrew Wilson has set forth an entirely new
theory.* With reference to the fact that the centre
controlling the movements of the right arm is
situated near the centre of speech in the left hemi-
sphere of the brain, he asks : " Is it not probable
that the superiority of the right side of our bodies
has kept step in growth with the development of
language ? " He denies right-handedness to be the
outcome of continued practice from childhood in the
use of the right hand, and considers it the result of
evolution from ambidexterity. Dr. Wilson gives no
explanation of left-handedness, to which Sir Daniel
Wilson has dedicated a whole book.
The explanations given by the late Dr. Fritz
Lueddeckensf for left-handedness as well as right-
handedness are very detailed. This German doctor's
treatment of the subject is anatomical throughout,
and is based upon thorough investigation. The
keynote to his exposition is his unqualified rejection
of the theory that right- or left-handedness can rest
upon habit. Among other things, he says that the
hypothesis " is absolutely untenable that man should
more and more restrict the collaboration of one half
of the brain and become accustomed to the conse-
quent use of one hand if it were true that both
cerebral hemispheres had originally equal functions."
The mere anatomical fact that the centre controlling
the muscles for speech is fully developed on one
* " The Light Side of Science." (Chapter on "Right-handedness.")
I "Die Ursachen der Rechts- mid Linkshiiendigkeit." Leipzig, HJ00.
208
KNOWLEDGE.
June, 1913.
side only of the brain — in the case of the right-
handed on the left side — excludes the accuracy of
the theory of habit as an explanation of right-
handedness.
Dr. Lueddeckens opposes the widespread belief
that left-handedness is a phenomenon restricted to
the hand. On the contrary, it affects the physio-
logical character of the whole left side, which
presents the same characteristics in the left-handed
as does the right side in the right-handed. ' This
thesis, which Lueddeckens endeavours to confirm in
detail, is the leading feature of his researches,
together with the preponderance of the left hemi-
sphere of the brain over the right as the chief
explanation of right-handedness, in which, as we
have seen, Bolk and Biervliet also agree. In support
of this theory he examines not only the hand but
the arm, brain and spine, the ear, speech, walk,
sleep, psychic processes, the whole muscular system,
and so on, giving particular attention, however, to
the eye. His manifold observations have enabled
him to recognise left-handedness, as a rule, in the
dilation of the left pupil. As science, the statements
about the eye are the most important and valuable
in his book.
He emphasises that James Mark Baldwin also
considered "the prevalence of the left half of the
brain" the natural cause of the predominance of
right-handedness, and he quotes from this celebrated
investigator's book on the mental development of the
child interesting experiments that Baldwin made
with his own infant daughter. In the first place he
would not allow the child always to be carried on one
arm. From the fourth to the tenth month he placed
her daily at a fixed hour in a comfortable sitting
posture and let her reach out after the most varied
objects. During this time he found that no
preference was shown for either hand, but it must
be noted that no exertion was exacted. As soon
as the distance was increased from ten or twelve
inches to fifteen inches the child at once evinced
a marked preference for the right hand. In the
first period of the experiment she stretched out her
right hand five hundred and seventy-seven times,
her left five hundred and seventy-eight times, and
both hands at once one thousand and forty-two
times, and in the second period, at an increased
distance of the object, out of eighty tests she used
her right seventy-four times, the left only five times
and both hands together but once. At a distance of
thirteen to fifteen inches she used her right hand
alone for seizing. If the object were shifted to
the left all the greater exertion was made by the
right hand in the domain of the left, while there
was a diminution in the use of the left hand. On
the other hand, I must mention Dr. Manfred
FrankePs assertion that Baldwin's experiment, put
by himself (Dr. Frankel) " to a test with several
children and many trials, in no way verified itself."
The right-handed only sleep well on the right side
as a rule, and if they fall into a heavy sleep on the
left side they often have unpleasant dreams, and
sometimes nightmare or pollution. The left-handed,
again, generally only sleep well on the left side. The
reason is that the pressure of blood is higher on the
right side of the brain with the latter, and on the
left side with the former. Similarly also, according
to Lueddeckens, the characteristics of the left side of
the left-handed correspond in every detail with the
characteristics of the right side of the right-handed.
As the result of numerous observations, " I was
astounded," he writes, " at the degree of conformity
manifested by the two states or conditions, resembling
an object and its mirrored reflection." He lays
great weight on heredity in cases of left-handedness.
He gives dates and tables showing the frequent
recurrence of left-handedness in one and the same
family in many instances. With regard to left-
handedness in school children, he says in part : —
" Cases of left-handedness are, as a rule, soon
noticed at school, especially in writing. Although
the scholars, often with great difficulty, learn to
write with the right hand the characters that are
adapted to right-handedness, very many of them
show the inclination to use the left. Later, when
they notice that it is unpleasant to write against the
point of the nib, they often begin to write from right
to left in so-called mirror writing, in which they
often attain remarkable facility with a relatively
small amount of practice. . . . When requested
to write her name with her left hand, a left-handed,
mentally deficient schoolgirl of twelve executed it
in mirror writing, and when a church with a tower
to the left and a house to the right was drawn for
her, she copied it with her left hand, beginning at
the right side of the paper and drawing the tower
first, and then, working towards the left, the house.
She had learnt at school to write and also knit in
the customary right-handed manner, but at times
she fell back to knitting with the left hand. Such
cases of mirror knitting are probably rare in
Germany, though another case had been noticed
before in the same school. In any case, it proves
what technical difficulties will be overcome instinct-
ively, even where there is mental deficiency, by left-
handedness in order to assert itself."
According to Wilhelm Fliess also, in " Vom Leben
und vom Tod," in no case are the two sides of the
body in perfect symmetry, the left side being more
developed in one person and the right in another.
Other investigators as well are of the same opinion,
but there is novelty in Fliess' assertion that " the
significance of both sides changes with these
deviations, so that manly women and womanly
men manifest a fuller development of the left side
of their bodies. Left-handed men are always more
womanly, and left-handed women more manly, than
the right-handed of their sex. . . . When there
is deviation in the characteristics of the sexes and
the man is more effeminate, his female side, the left,
has a fuller development; and when the woman is
more masculine her male side, also the left, is more
developed." The connection between the accentua-
tion of the " left " side principle and the mixed
June, 1913.
KNOWLEDGE.
209
realm of male and female is thus shown. The side
corresponding with the opposite sex. i.e., the left, is
accentuated more strongly. "Accentuated " does
not imply by any means that the person in question
is always undoubtedly left-handed. This is as
problematic as it is interesting.
Broca's sensational discovery that the centre of
speech in the human brain is situated on the left
side, which was confirmed and extended by Bastian's
painstaking investigations, was all the more a matter
for wonder as the examination of animals gifted with
a certain power of speech manifested no such one-
sidedness. It was established that this one-sidedness
in man was connected with his right-handedness.
Further research showed that in the case of the left-
handed the centre of speech was situated in the right
cerebral hemisphere. There was, therefore, no
longer any doubt as to the interdependence between
the left position of the speech centre and right-
handedness. Already in the seventh and eighth
centuries scientific men were aware that diseases of
the left cerebral hemisphere were very often attended
by difficulties in speech, whereas this was extremely
rare — only with the left-handed — in cases of disease
of the right half of the brain. This, too, confirms
Broca's discovery. A right-handed person may
suffer loss of speech through a blow on the left side
of the head, and a left-handed person by a blow on
the right side.
Consequently, people whose two hands are equally
skilful should have two speech centres. This seems
actually to be the case. Dr. Ernst Weber says that
it is easy to detect in children unmistakable traces
of two speech centres, but that later one of the
centres atrophies owing to the preference given to
one hand. But though it atrophies, it can be
aroused again and rendered useful by systematic
development of the other hand. How very far this
resuscitation can be made to go is shown in practice
by numerous successful experiments in trying to
make people ambidextrous by way of training the
left side. Of course, these experiences tend to
disprove Dr. Lueddeckens' utter disbelief in
gradually acquired habit as a possible cause of the
prevalence of right-handedness.
With regard to the number of cases of left-
handedness, Hasse and Dehner estimate it at one
per cent., many others at from two to four and a
half per cent., Flechsig at three per cent., and
Biervliet at two and a half per cent. The Bible
states that in the tribe of Benjamin, which
numbered twenty-six thousand seven hundred men,
there were seven hundred left-handed ; this would
be 2-62 per cent. Up to the present no one has
been able to draw up far-reaching statistics referring
to thousands of cases — and such alone would be
really reliable — as no investigator has examined and
compared more than a few hundred.
EFFECT OF SCHOOL WORK ON THE LUNGS.
By DR. ALFRED GRADENWITZ.
Interesting experiments have recently been made
by Dr. M. Oker-Blom, of Helsingfors, on the
respiratory movements on both sides of the chest of
twenty-five school children in the course of different
kinds of work, by means of an apparatus recording
any variations in these movements.* When reading
aloud was practised for three minutes, the upper
parts of the left lung were found to breathe more
deeply than those of the right lung, irrespective of
whether the pupil was seated or standing, the ratio
of the respiratory movements on the right and left
sides respectively being r : I = 100 : 118. This is,
of course, an average figure, there being sometimes
exceptions, especially in cases where the left lung is
somewhat abnormal.
The total number of respirations (r -\- I) on both
sides together during reading aloud is on an average
seventy-eight when the pupil is standing, but
decreases to seventy-two if he is sitting.
The most important point brought out by these
experiments, however, is the influence exerted by a
prolonged sitting posture on the respiration of the
upper part of the lungs. During a sedentary occu-
pation of some duration {e.g., knitting) the two sides
of the chest are found generally to have the same
amplitude of respiration, the breathing movements
of the left side being impeded more than those of
the right. This is accounted for by the frequent
changes in the position of the body which are made
involuntarily from time to time to alleviate the
fatigue in the back. In fact, even in cases where
there is no habitual scoliosis, the vertical column is
found alternately to lean to one side or the other,
the body straightening itself from time to time,
while a few deeper respirations ensure a certain
amount of compensation. In any case the unfavour-
able influence of any prolonged sedentary occupa-
tion generally is more marked in its effects on
respiration in the upper parts of the left side than
in those of the right. The total number of respira-
tions is found to decrease during uninterrupted
sedentary work lasting up to about forty minutes,
from seventy-two to thirty-nine, i.e., to about half
its original value. This is accounted for by the fact
that during sedentary work certain groups of
muscles are extended without interruption, thus
impeding the freedom of respiratory movements.
In order to obviate the harmful action of prolonged
sedentary work it is recommended that such work
should be from time to time interrupted by a few
minutes' respiratory gymnastics. Not only would
such practice prove beneficial as regards respiration
and pulmonary exercise, but it would, in addition,
have a certain prophylactic effect against scoliosis.
Internat. Archiv f. Schulliygiene,
POLISHED CELTS AND THEIR MANUFACTURE.
By T. H. POWELL.
The polished celt or axe probably represents the
highest artistic and manipulative skill of prehistoric
and savage peoples ; its outline in fine specimens
being perfectly symmetrical, its poise and finish
perfection, the skill and patience necessary for its
flaking and polishing must have been the result
of long experience under conditions of life where
time was of little value.
Whether used for cutting wood or as a weapon of
offence, a polished celt was necessarily subject to
great strain ; and it was, therefore, of primary import-
ance that a material should be selected which was
not only exceedingly hard, but without flaw,
otherwise the celt would fly to pieces directly it
was used.
If a stone, such as diorite, were chosen, this would
be a matter of little difficulty ; but in countries
where flint was the only material available, great
care and knowledge were required in the selection of
a suitable block which would prove homogeneous
throughout. The first thing, therefore, was the
selection of a suitable mass, probably fresh from the
quarry, as it was then more easily worked ; and this
m^ss, somewhat larger than the implement to be
made, was flaked into a rough oblong with broad flat
surfaces with thinner sides and ends. The two
ends were then flaked longitudinally, the butt only
slightly, but at the opposite end the flaking was
continued, first on one side and then on the other,
till the edges along the plane of flaking met, and a
rough, slightly curved outline resulted (see Figure
225). One of the sides was then chipped from end to
end at right angles, the flakes struck off being
smaller than at the butt and cutting ends, and the
four edges were successively dressed in a similar way
till two wedge-shaped sides resulted (see Figure 219).
The two broad faces were then trimmed all over in
such a way that the celt was thicker along the centre
than at the edges (see Figure 224). The next process
was the production of the cutting edge, and it is at
first difficult to understand how this was done, as
the edge is often so true and sharp that no amount
of face orsidegrinding could possibly have produced it.
But a comparison of examples will show that it was
made much as follows. The roughly flaked mass was
held upright in the hand, with the narrow side
towards the workman, and the curved edge rubbed
backwards and forwards on a piece of quartzite or
sandstone, with a rotary movement, till perfectly
smooth and symmetrical, the outline aimed at
being exactly the same as in the finished article.
The celt was then held obliquely, and rubbed back-
wards and forwards until the broad surface on both
sides extending for an inch or more from the cutting
edge became smooth and the edge was perfectly
thin and sharp (see Figure 217). In many cases
very little else was done, the butt end being left
in a rough state so that the haft would grip it more
firmly ; but in the finest examples the grinding and
polishing were extended over all the surface from
one end to the other both on the faces and sides
(see Figures 220 and 222). It is a curious fact that
although broken cutting ends of celts are compara-
tively common (see Figure 214) broken butts are
rare. The explanation probably is that the sharp
cutting end could often be remounted and used
again, or if only an inch or two in length it would
form a serviceable wedge. In the case of the butt,
however, it seems probable that the fragment, being
of fine quality and having cost so much time and
labour to produce, was regarded by its owner as a
treasured possession, and was used up again for a
variety of purposes. If the piece were large a smaller
celt could easily be made from it ; but if not of
sufficient size for that purpose it was made into
some other tool, and every good collection contains
examples of borers, scrapers, knives, and even
hammer stones showing old polished surfaces (see
Figures 212, 213, 215 and 216).
It must often have happened that the sharp edge
became blunted or damaged in use, and resharpening
became necessary. This was easily done by striking
off small flakes from both sides, then grinding down
until the curved edge again became true and sharp,
and finally rubbing down, till all marks of flaking
were obliterated and repolishing was complete (see
Figure 223).
The method employed in the case of diorite and
similar tough rocks was altogether different ; flaking
was out of the question, so the stone was struck or
pecked into the required shape and the rough
surface subsequently rubbed and polished (see
Figure 218).
Flint and the many other materials made use of
in the manufacture of celts are necessarily of great
hardness. It must be evident, therefore, that the
grinding process was both slow and laborious, and as
in the finest examples all trace of flaking is com-
pletely rubbed away, a polished celt may be
regarded as evidence, not only of great skill, but also
of almost infinite perseverance and patience.
210
June, 1913.
KNOWLEDGE.
211
Figure 212. Figure 213.
Flint implements, formed from
broken or damaged polished
celts.
Figure 214.
Cutting edge end of a fine flint celt,
two and a half inches long, from the
Sussex hills, probably broken in use.
/-/
Figure 215. Figure 216.
Flint implements, formed from
broken or damaged polished
celts.
Figure 217.
Chert celt, with
cutting edge sharp-
ened and nearly
finished by rub-
bing, six and a half
inches long (from
Denmark).
Figure 222.
Flint celt, eight and
three quarter inches
long, polished on all
surfaces (from Den-
mark).
Figure 218.
Celt of hornblende
diabase, four and
a quarter inches
long, from the Ox-
fordshire hills, of
perfect shape and
finish.
Figure 219.
Side view of flint
celt, showing the
wedge - shaped
form (from Den-
mark).
Figure 223.
Flint celt undergoing process of re-
sharpening ; the extreme cutting edge
is smooth and somewhat thick, thence
for about one inch small flakes have
been struck off. This only requires
rubbing down to produce a perfectly
sharp edge. Eight inches long.
Figure 220.
Flint celt from the
Beck Collection,
said to have been
found at Pul-
borough, Sussex, a
beautifully finished
Danish implement,
five and a half
inches long.
Figure 221.
Flint celt found
near Horsham,
Sussex ; the rub-
bing process begun
all over the sur-
face, six inches
long.
Figure 224.
Flint celt, eight inches
long, flaked into shape
and ready for polishing
(from Denmark).
Figure 225.
Oblong block of chert,
nine inches long, with
roughly flaked ends, the
cutting edge rounded, the
one edge trimmed, the
other still in the rough
(from Denmark).
SUGGESTIONS TOWARDS A SOLUTION OF THE
PROBLEM OF THE IBERIAN PLANTS IN
SOUTH-WEST IRELAND.
By G. W. BULMAN, M.A., B.Sc.
We do not propose to give here any review of the
subject, or to criticise any of the explanations which
have been brought forward. On the assumption
that a land connection between Spain and Ireland
was necessary, and that such really existed, we offer
a suggestion as to why these Irish species do not also
occur in England. None of the theories we have
come across explain this, or even admit it as a
difficulty.
Again, assuming that the land connection was
pre-Glacial, and that there has been none since the
retreat of the ice, we will enquire what grounds
there are for believing that much of our present flora
may have survived glaciation.
As regards the first point, it is practically
impossible to imagine a land connection between
Spain and Ireland which did not also include
England. And it is to be remembered that Cornwall
also has its own peculiar species of Southern plants,
which equally need a land connection. The Spanish
plants spreading across the assumed land bridge
would have had time to reach England also. Why
are they, then, not found in this country ? One is
inclined to suggest at first — and the suggestion has
indeed been made — that they were driven out by the
cold of the Glacial epoch everywhere but in the south-
west of Ireland. To this, however, it may be replied
that if they could survive there they could surely
do so also in Cornwall and the Scilly Islands. We
propose, then, another explanation, founded on the
influence of the geological structure of the land on
the spread of plants. Let us suppose a set of plants
spreading northwards along a line sufficiently
extended to reach along our south coast to some
distance west of the extreme south-west corner of
Ireland. Normally such a migrating band of plants
would reach England and Ireland simultaneously.
But let us suppose that the advancing front of the
Iberian plants meets with a wedge-like barrier of
unsuitable ground, mountains, desert, marsh, on
merely a different sort of rock. The advance is
thereby turned to the north-west and north-east or
the two sides of the barrier. The former branch in
due course reaches the south-west of Ireland, and
the then existing land to the west of this. The
other diverges so far that by the time it reaches our
latitudes it is too far east to touch our shores. Or
the nature of the barrier may have been such as to
stop the species altogether from getting further
north. The present continental distribution of the
species in question, if known in sufficient detail,
might possibly indicate which way it was. But the
barriers of unsuitable country which prevented the
Irish species reaching England may have favoured
the spreads of the southern species now found in
Cornwall, and the migrating area of the Cornish
species may have tapered northwards, and had its •
apex in Cornwall, which would account for their
absence in the eastern part of southern England.
As regards our second point, a careful considera-
tion of the facts seems to suggest the possibility — if
not the strong probability — of the survival of many,
at least, of our native plants over the Glacial epoch.
That the whole of our flora and fauna was driven out
or exterminated by the cold is, perhaps, only held by
those who have had the " Glacial nightmare " badly.
Yet even those who take more moderate views
might be excused for doubting the possibility of a
fragment of the Spanish flora surviving glaciation
in the south-west of Ireland. Let us ask, then,
What evidence can be brought forward indicating the
possibilities of survival ? The present flora of Green-
land seems to furnish a strong argument. In spite
of its glaciation this country possesses at the present
day a considerable number of species of flowering
plants. Some of these are members of our own
flora. Even, then, if we suppose the glaciation of
our land was as severe as that of Greenland to-day,
we have here absolute proof that some of our species
could survive. But it is not probable, in fact, it
seems impossible, that the climate of Glacial Britain
was as severe as that of Greenland to-day. Even if
the amount of ice and snow was as great, or greater,
Britain would still have the advantage of its more
southern latitude. The amount of heat received
during the summer would be as great as — or,
according to some authorities, greater than — at
present. The amount of land freed from ice
and snow during this season would be greater, and
the time it remained free longer. Thus, there would
be a greater possibility of survival than in Greenland
to-day. But this is not all. It is difficult to under-
stand how Greenland can have received its present
flora since the Glacial period. The ordinary means
of transport, winds, ocean currents, and so on, are not
available for Greenland ; nor is there any suitable
land connection ; and Greenland's migratory birds
go to it in the spring when there are no ripe seeds
for them to carry. It almost seems as if we would
have to grant that Greenland's present flora survived
212
June, 1913.
KNOWLEDGE.
213
the Glacial epoch there. But if this flora survived,
in Glacial Greenland, the necessarily severe con-
ditions, may we not be almost absolutely certain that
our flora could survive in milder Glacial England ?
And then there arises the interesting botanical
question : Does it require a plant to be of a hardier
constitution to stand being covered with snow or ice
for several months, and then have a warm summer
— as it would during glaciation — or to be alternately
frozen and thawed — as it is apt to be in our uncertain
climate to-day ? In other words, would it kill any
of our native species to be so treated? A deep cover-
ing of snow and ice, in fact, keeps the earth warm.
That is why we usually see a stream of water
issuing from beneath a glacier. And it is to be
remembered that a country covered with ice and
snow is not necessarily as cold as Siberia, or the
Antarctic. Nor because an ice-sheet or glacier came
down to the latitude of London need we suppose that
a temperate vegetation could not flourish there. At
present alpine glaciers end amid a varied flora, while
in New Zealand glaciers come down to the regions
of a sub-tropical vegetation. In North America,
again, the limits of the forest go up into the ice, and
the limits of the ice come down into the forests. Ice
and snow require only a temperature of 32° F. for
their formation, and unless there are other causes
than the presence of these, there need not be intense
cold. And it is to be remembered that every pound
of water frozen means the setting free of enough
heat to raise eighty pounds of water 1° C. Hence
the enormous quantities of ice and snow imagined
by extreme glacialists do not necessarily imply a
proportionately lower temperature. The cold is, so
to speak, used up in freezing the water.
The fact that our little group of plants is confined
to the south-west corner of Ireland, and that they
are Spanish plants, inclines us to view them as
tender species. And this makes one of the special
difficulties of the case. How could such tender
species survive ? But may they not in reality be
hardier than the facts suggest ? The Arbutus
stands the winter and ripens its fruit in the southern
counties of England, while London Pride is a
perfectly hardy plant which does not suffer in our
severest winters. Information as to the altitudes
attained by the various species in the Pyrenees
might help to settle this point. And the fact that
some of our species are also natives of Greenland
suggests that a group of Spanish plants might be
hardy enough to be natives also of a more northern
latitude.
But it may be asked, If our plants did survive
glaciation, ought there not to be some positive
evidence in the form of fossils ? The difficulty of
obtaining such actual evidence of survival in glacial
deposits arises from the fact that many geologists
believe that there have been several Glacial periods
in Pleistocene times. Thus, if remains of temperate
plants are found in such Glacial deposits, the actual
beds containing them are classed as inter-Glacial.
The plants which had been exterminated by the cold
are supposed to have come back during a warm
inter-Glacial period. Personally, we have defended
the case of one Pleistocene Glacial epoch (Geological
Magazine, August and September, 1891). And, if
this is correct, then there is abundant evidence of
the survival of temperate plants during glaciation.
But, even on the view of several glaciations, there
are not wanting cases where temperate species occur
in deposits which are classed as Glacial by reason of
the Arctic species which they also contain. Mr.
Clement Reid, who advocates the view of several
Glacial epochs, and believes that all temperate species
were exterminated by the cold, gives detailed lists of
species found in various Glacial, and so-called inter-
Glacial, deposits. Glancing through these as
given in his " Origin of the British Flora," we realise
that it must often have been extremely difficult to
the author to decide from the plant remains whether
the deposit should be classed as Glacial or inter-
Glacial. We will take one or two illustrations of
this from the above work in support of our con-
tention. Thus, a deposit near Edinburgh is described
as follows : —
"In the lower part of the lacustrine deposits
filling a silted-up lake are numerous seeds and leaves
of Arctic plants. The deposit is probably Late
Glacial."
Yet the plant list appended contains such
temperate forms as the Creeping Buttercup, the
Marsh Violet, the Dandelion, the Bogbean, and so on.
Another deposit, yielding Arctic plants, has in
addition to the above temperate forms, Campion,
Wood Sorrel, Knot-grass, and so on. Examples of
such mingling of Arctic and temperate forms might
be multiplied, and even on Mr. Clement Reid's own
interpretation of the order of events they seem to
indicate the survival of the latter.
Finally, if there is no evidence of a />osr-Glacial
land connection, and if we cannot satisfactorily
account for the presence of the peculiar flora of
south-west Ireland by other means of dispersal,
this in itself is a proof of the possibility of survival.
ANNOUNCEMENTS.
EUGENICS as a practical science is now recognised by
sociologists as an important factor in race culture ; and the
Eugenic Club Committee cordially invite the co-operation of
ladies and gentlemen who are interested in Eugenics and
kindred subjects to communicate with the Secretary, 6, Hand
Court, High Holborn, W.C.
MUSEUM EXTENSION AT HULL.— A further valuable
gift has just been made to the Hull Municipal Museums Com-
mittee by C. Pickering, Esq., J. P., the donor of the new Museum
of Fisheries and Shipping at the Pickering Park. It was
recently represented to him that the new museum was already
crowded with exhibits, and he has kindly presented a strip of
land stretching from the Hessle Road to the Pickering Park, and
adjoining the present museum, for the purpose of extension.
TRYPANOSOMES.
By MALCOLM EVAN MACGREGOR, F.R.M.S.
(Continued from Page 200.)
The Effect of Trypanosomes on Man
and Animals.
Both in man and animals the effect that
pathogenic trypanosomes have while living in the
blood is very similar. We will first consider a case
of sleeping-sickness in man.
Long ago, when Livingstone penetrated into the
heart of Africa he noticed that as he got into certain
regions of Central Africa the natives spoke of a
disease which made people sleepy, and that the
invariable result of this sleepiness was death.
Recognising this and the hopelessness of curing
people of the disease when once they had contracted
it, the natives were wont to banish the poor unfor-
tunate sufferer from his tribe, so that ere long,
without anyone to help or look after him, he died
of starvation. What brought this disease, or how it
wa,s caught, nobody knew ; but while in those days
it was more or less confined to comparatively small
areas, it has now, since Livingstone's day, spread
gradually in Central Africa, and by the name of
sleeping-sickness has come to be known as one of
the most dreaded diseases of mankind. The
trypanosome which causes sleeping sickness is not
confined, it is thought, to one species. In the
Gambia and other parts of tropical Africa the
organism is T. gambiense. In Nyasaland and
Rhodesia it appears to be caused by a trypanosome
of slightly different form, to which has been given
the name T. rhodesiense.*
The picture of a man suffering from sleeping
sickness is a very terrible one (see Figure 226).
At first, after he has been bitten by an infected fly,
there may be little to notice the matter with him,
and the parasites may be in the blood for several
months without causing any marked effect — in fact,
so long as they remain only in the blood-stream
they seem to do little harm.
But after a time they appear in the cerebro-spinal
fluid, and then their deadly work begins.
The man's temperature goes up, and he feels
generally tired, and exhausted by the slightest effort.
He becomes hyperaesthetic, so the little everyday
knocks that he receives from surrounding objects
while he goes about his everyday duties, and to
which, while he is well he pays no attention, cause
him the intensest pain. There may now be tingling,
or even pain, in the soles of the feet and palms of the
hands, and peculiar reddish patches may occur on the
skin. This continues for a varying period in different
cases, but finally it gives place to just the reverse con-
dition where the patient loses feeling, and gradually
becomes stupid, sinking into a heavy lethargy, from
which it becomes impossible to raise him. At first
this condition is manifest, when one speaks to the
sufferer, by his apparent lack of interest in the
subject of conversation; he is constantly failing to
follow the drift of things, but by raising the voice
he is made to grasp what is being said. This con-
tinues, and rapidly becomes worse, until in the end
a pistol could be fired a few inches from the person's
head without his responding at all. There is a dull,
sleepy expression about the face ; oedema under the
eyes and elsewhere causes the skin to have a puffy
look, and the man presents the appearance of a
person utterly exhausted from want of sleep. So on
it goes, until the patient lies completely comatose,
the coma ending in death.
This is, to some extent, the outward picture of the
man, but besides these symptoms he presents an
extremely emaciated condition, and general anaemia.
There are infiltrations of lymph into the body
cavities, the spleen is usually enlarged, and there are
changes in the grey matter of the brain and spinal
cord ; but on the whole the visible damage to the
body is not great.
Sleeping-sickness in man is a prolonged disease,
and may last as long as three years from the time of
its onset to the death of the patient.
In animals, sleeping-sickness produces much the
same effect, but its course in the smaller animals, such
as the rabbit, the guinea-pig, and the rat, is of much
shorter duration, terminating, of course, in the death
of the animal.
The actual condition of " sleep " is perhaps not so
manifest as it is in man,. but it is present neverthe-
less, and very noticeably in the case of the rat, which
places its head between the front paws, rests the
crown of the head on the ground, and, throwing the
body well forward, looks for all the world as if it
were endeavouring to " stand on its head."
It was at first thought by many tribes of natives
in Central Africa that sleeping-sickness was caused
by the eating of the m'lolo root (manioc), a root that
is eaten fairly extensively. Then came the idea that
it was produced by eating a certain species of mud-
fish, or that it was caused by " integarti" (the native
name for devils). Finally, it was recognised that
tsetse-flies had something to do with it, and the
tsetse-fly was credited with having a " powerful
poison," which it injected while it bit, and that it was
:,; See Footnote on Page 199.
214
By kind permission of the Royal Society.
Figure 226. A case of Sleeping-sickness in a Native Child. The last stage in the disease, where, as it
will be seen, there is complete coma and extreme emaciation.
By kind permission of the Royal Society.
Figure 227. A group of Natives and their Children, upon whom the ravages of Sleeping-sickness and
starvation are prominently in evidence.
215
216
KNOWLEDGE.
June, 1913.
this poison which ultimately killed the animal or
person — a theory that at basis was almost right.
But all these theories, and many others, have
been exploded completely by the discovery of the
trypanosome in the blood of sleeping - sickness
patients, and which long since has been proved to
be the cause of the disease.
An interesting idea was that the European was
less prone to sleeping-sickness than the native, but
so far as his susceptibility to the disease is con-
cerned the idea is entirely wrong. There is some
truth, however, in the statement that a smaller pro-
portion of Europeans than natives are attacked ; but
this is probably, in part, due to the fact that most
Europeans are not subjected to the same risk, living,
more or less, indoors during the day, when the
tsetse-fly is at the height of its activities. On the
other hand the natives are in the open all day and
always subject to the fly's attentions.
There is, nevertheless, a curious thing that has
often been noticed, and which undoubtedly has a
good deal of bearing on this subject, and that is the
tsetse-fly's marked aversion to settling on anything
white. It is the prevailing fashion, of course, for
the Europeans of tropical parts to dress in white
duck, and it has been observed that when a
European so dressed and natives have gone to a
spot where flies are abundant, the natives are
attacked most mercilessly, while the European is
comparatively unmolested. That this is due to the
colour of his clothes has been proved by tacking a
square of black cloth over, say, one arm, when
instantly, under the same conditions, the flies will
settle on the square. It is probably that the fly
instinctively will not settle on white owing to its
becoming then conspicuous.
Notwithstanding this, all things being equal, the
European quite as readily falls a victim to sleeping-
sickness, and he possesses no natural immunity.
Nagana, or the African " fly-sickness " of cattle, is
produced, as has been mentioned before, by T. brucei,
a trypanosome very similar in some of its phases to
T. gambiense, but which at other times is met with
as a small trypanosome of tadpole-like shape, having
neither undulating membrane of any width nor
" free flagellum." Besides cattle it attacks dogs and
cats, while it is pathogenic to most small animals as
well. It is harmless, however, to man, and it is found
in the blood of wild antelopes and other big game,
in which it seems to cause no ill-effects, strangely
enough.
Nagana constitutes one of the great cattle plagues
of Africa, and has done untold harm to the develop-
ment of the country for stock-raising ; for it is
impossible to keep even domestic stock where this
disease occurs. Its effects on the animals it attacks
are essentially similar to the effects produced by T.
gambiense, with only minor differences. " Nagana "
is a Zulu name, and means " breaking, or withering
up," and this name describes the course of the
disease very well, since the animals present a most
lamentable appearance of utter weakness.
The tsetse-fly responsible for the spread of
Nagana is Glossina morsitans, a tsetse - fly
resembling G. palpalis in many ways, but its body
is of a lighter brown colour, and has characteristic
markings on the abdomen. Morsitans is the
commonest of the tsetse-flies, and is widely spread
over Africa ; moreover it is not confined in its haunts
to water-tracts.
Treatment.
Now we come to the last consideration, namely,
the cure of trypanosome diseases. A great deal of
work has already been done in this direction, but
there is a vast amount more needed yet. There is
practically no cure whatever, although there have
been rare cases of apparent recovery, which, quite as
likely, were due- to the patient's own bodily strength
as to the success of any " treatment " he mav have
had.
The drugs known as atoxyl and arsacetin* and
other arsenic-containing compounds may be said to
be the standard drugs used in the treatment, but an
enormous number of substances of all kinds have
been tried.
All the drugs like atoxyl are violent poisons, and
so have to be used with extreme caution, or the
" remedy " becomes worse than the disease, and, in
the case of atoxyl, blindness is very easily produced
in the patient by the slightest overdose.
Although these drugs do not produce permanent
good, they seem to have a beneficial effect some-
times, and if cure meant only the ridding of the
patient's blood from trypanosomes, they would
indeed be admirable cures. Their effect in this way
may be quite remarkable, for while the patient's
blood may be swarming with trypanosomes, a dose
of atoxyl will completely free it from the parasites
in the course of an hour or two. Moreover, it may
remain free for months actually, but sooner or later
the trypanosomes will reappear, and the course of
the disease is not interrupted in reality. What
happens to the trypanosomes under the influence of
atoxyl nobody knows exactly. It has been said
that they " hide " in the bone-marrow or form
invisible spore forms, but all the same nobody knows
perfectly where they go or what they do in the
meantime.
Apart from the drug treatment there is another
way of fighting the disease which, while it does not
aim at curing people who have already contracted
sleeping-sickness, does nevertheless aim at a decided
check to the spread of the disease. This consists in
removing the natives away from watercourses and
areas that the tsetse-fly inhabits, in confining all
people suffering from the disease to isolation-camps,
in destroying the undergrowth of river and lake
/NH, /NH.CO.CH:,
Atoxyl = CcH4<f Arsacetin = CCH4\
XAsO.(OH).ONa XAsO . (OH) . ONa
June, 1913.
KNOWLEDGE.
217
banks near roads and villages — for the tsetse-fly
needs the undergrowth as a breeding place — and in
the control of natives living in infected areas by
preventing their migration to other parts until they
have been proved free of the disease.
Since trypanosomes do their work of destruction
by some poison — toxin — they secrete, or by using up
some essential substance in the blood of their host,
which the host needs for the continuance of its life ;
and since the multiplication of the parasite in the
host's blood is unchecked except by the ultimate death
of the host, it is safe to conclude that, unlike some
bacterial diseases, the body in this case is unable to
produce an antitoxin by which to rid itself of the
infection. Therefore, I do not think that any
" vaccine-treatment " will ever be found of any avail,
but the cure must come through the discovery of
some drug that shall deal death to the trypanosome
and yet not poison the patient. It is not, however,
that the trypanosome in itself possesses any
extraordinary vitality that makes it difficult to kill
but it is merely its position in the host's blood
which gives it its present unassailable position ; for
drugs that are harmful to it are equally harmful to
the tissue-cells of the host, and effectually to poison
the one means, just as effectually, to poison the
other. Trypanosomes in fluid media — blood, and so
on — when raised outside the body, only a few-
degrees above the normal animal temperature, quickly
succumb. Were it possible to keep the infected
animal at such a body-temperature without killing
it, that, perhaps, would be the simplest method of
cure ! Needless to say this is quite an impossibility,
and so, notwithstanding all that has been done
up to the present, the difficulty in the cure of
trypanosome diseases still awaits solution.
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
THE MOUNT WILSON ONE HUNDRED - INCH
REFLECTOR. — Some good news about this great instrument
has arrived from California. It was previously reported that
the glass disc for the mirror had proved a failure, but it has
now been found that the fault was only in the method of
mounting, which caused flexure ; an improved method gave
satisfactory results, and the disc has been accepted and paid
for, which indicates confidence that it is sufficiently good.
We may hope for some wonderful results in stellar astronomy
when this giant instrument is complete. Even the sixty-inch
shows stars of the twenty-first magnitude.
THE SPECTRO-HELIOGRAPH.— The Gold Medal of the
Royal Astronomical Society was given this year to M. Deslandres
for his work on the Sun. The address of the Astronomer
Royal gives an interesting summary of his work, calling attention
to the spectro-heliograms of the lower, middle and upper layers
of the solar atmosphere, which are obtained by shifting the
second slit to the outside, intermediate, or central region of
the K line. In the upper-layer photographs the prominences
can be seen both inside and outside the disc, and it is possible
to say whether a limb prominence has its base on the near or
remote hemisphere of the Sun and to localise it exactly in the
former case. The ordinary limb observations of prominences
do not admit of this. Another interesting feature of the high-level
spectro-heliograms is the system of long dark filaments, which
play the same important part in this layer that spots do in the
lowest one. They form a network over the whole disc and
sometimes persist for several rotations. They are intimately
connected with prominences, one of these being generally
present where they cut the limb. M. Deslandres finds that
they are centres of rotation about a horizontal axis, the spots
rotating about a vertical one. It was also found possible to
obtain spectro-heliograms of these in the hydrogen light, using
the Ha line, though its narrowness made the difficulty greater
than in the K line of calcium. The upper layer of hydrogen
shows the same filaments as the calcium ones, while the
middle layer shows the vortices round spots, which Hale was
the first to detect. Deslandres also devised the " Velocity
Recorder," which is a spectro-heliograph with a wide second
slit, enabling the whole width of the line to be photographed.
As the slit traverses the solar disc, variations in the position
and width of the line give indications of the motion of gases
in the atmosphere of the Sun. He concludes that on the
whole the bright regions are descending and the dark filaments
ascending. He thinks that the circulation of a sun-spot is
as follows : — The gases in the surrounding regions are ascend-
ing, then they approach the facula and go down in it, a
continuous circulation being maintained. If the downward
motion prevails, the lowest layer may be pierced and a spot
formed, while if the upward current prevails a prominence is
formed. He also finds in the varying rotational velocity of
different parts of prominences (the base having the more
rapid rotation) evidence of the existence of a magnetic field in
the higher layers, just as Hale had found it in the vortices
surrounding spots.
Another interesting solar paper was read at the April
meeting of the Society : it was by Mrs. Evershed (Kodaikanal),
and was accompanied by a beautiful series of prominence
photographs. A certain type of explosive prominence appeared
to be intimately connected with spots, and in several of these
prominences there was evidence of outward motion, which
was, however, slow, this being a different result from that
found by Slocum, who noted inward motion. The photographs
will be reproduced in the Monthly Notices, and it will then
be possible to follow the argument more closely.
SPIRAL THEORY OF THE MILKY WAY.— The idea
that the Milky Way may be a spiral has been many times put
forward. I think Mr. Proctor was the first to do so. Dr.
Easton, who is well known for his studies on the subject, gives
in The Astrophysical Journal for March a small-scale diagram
of the whole Milky Way from a combination of photographs
and eye drawings, also a spiral form that he suggests might
account for the appearance, though he adds that he does
not insist on the accuracy of the details. It is of the Catherine-
wheel kind, consisting of several curved streams radiating
from a large nucleus, which he places in Cygnus. The form
was suggested by several spiral nebulae, notably the one in
Canes Venatici. At many places the streamers point straight
towards us, this being his explanation of brighter portions ;
since we see a great depth of galactic matter in such streams.
He makes one stream pass through the solar system, which
seems improbable, as the evidence of the proper motions is
that no part of the Galaxy is very near us. The spiral theory is
rendered more probable by the fact that a spiral structure is
suspected for the Magellanic clouds.
SPECTROSCOPIC DETERMINATION OFTHE SUN'S
ROTATION. — Many astronomers have investigated the Sun's
rotation in this manner in recent years. The obvious advan-
tage is that it can be extended to all latitudes, while the
visual method by the spots is confined to the tropical regions.
Moreover the spots are clearly of the nature of great disturb-
ances in the photosphere, and there is some objection in
using them to give the motion of the undisturbed regions
218
KNOWLEDGE.
June, 1913.
The spectroscopic method can be extended to the poles and
to undisturbed regions of the surface, and there is the
possibility of examining the lines of different elements and
seeing whether they indicate the same velocity. The draw-
back of the method is that the linear velocity of rotation, even
at the Equator, is only two kilometres per second ; and though
this is doubled on comparing opposite limbs it can hardly be
determined by the spectroscope within about three per cent.,
which means an uncertainty of nearly a day in the period.
The three most reliable series appear to be those of Adams,
Plaskett and DeLurv, the last two having been made at Ottawa
in 1912, and published in The Astrophysical Journal for
March.
Table 40 gives the smoothed mean values of the
three determinations for each five degrees of solar latitude.
They are smoothed by the formula 10°-31+4°-03 cos2
latitude. The values from sun-spots (due to Adams) are
given for comparison, also the times of sidereal rotation of
different zones.
Table 40.
Lati-
tude.
Spectroscope.
Sun-spots.
Daily
Angular
Rotation.
Period of
Sidereal
Rotation.
Daily
Angular
Rotation.
Period of
Sidereal
Rotation.
Carring-
ton's
Value.
0°
14-34
d
25-11
14° 40
d
25-00
.1
24-92
5
14-31
25-16
14-38
25-03
25-00
10
14-22
25-32
14-31
25-16
25-19
15
14-07
25-59
14-20
25-35
25-47
20
13-87
25-95
14-06
25-60
25-73
25
13-63
26-41
13-89
25-92
30
13-34
26-98
13-69
26-30
26-47
35
13-02
27-65
13-47
26-72
40
45
12-68
12-32
28-39
29-22
( 28-46
t South
50
55
11-98
11-64
30-05
30-92
( 27-45
1 North
60
11-32
31-81
65
11-03
32-64
70
10-79
33-37
75
10-58
34-03
80
10-43
34-51
85
10-34
34-82
90
10-31
34-91
There seems to be no clear evidence of different rates from
the lines of different elements, such differences as are found
being comparable with the probable errors.
Carrington's adopted period for the sidereal rotation is
25-38 days, which corresponds with latitude 14° 6'. His
values for 45° and 50° are from too few spots to be reliable.
ULTRA-NEPTUNIAN PLANETS.— I have read with
interest Mr. Ling's paper on this subject in the May number,
page 171. There are two little points on which I desire to
comment. First, at the end of his paragraph (2) he implies
that a planet of mass five times the Earth's, at a distance
fifty-two, would not sensibly perturb Uranus. But, as Dr.
Cowell pointed out, the perturbations which one planet pro-
duces on another depend only on the mass of the first and the
ratio of the distances of the two planets from the Sun ;
consequently a planet of mass five times ours would produce
the same perturbations (in heliocentric longitude) on Uranus
that our Earth would on Mercury if our mass were increased
fivefold ; but even the present perturbations of the Earth on
Mercury are sensible, so that those of the fivefold Earth would
be readily so; in the case of planet O and Uranus the
slower motion and the longer time for perturbations to
accumulate make up for the increased distance between the
planets. Again, on page 172 he says that an unexplained
rotation of the major axis of the orbit of Halley's Comet
undoubtedly exists. If he compares the predicted elements of
the orbit with the observed ones he will see that they accord
within a few seconds. The discordance of two days does not
arise from a rotation of the orbit, but from an alteration in
the comet's mean anomaly.
OBITUARY. — I have heard with regret of the death of
Professor F. W. Ristenpart, Director of the Observatory of
Santiago, Chili. When in Berlin he commenced and partially
carried out a very useful work, the combining of all star
catalogues into one great catalogue, with determination of
proper motions. He discovered a great many errata in the
catalogues in the course of his work, and these have already
been circulated. He went to Santiago about four years ago.
Some interesting observations of his have been published,
notably the organising of the observers who watched the
occultation of a small star by Ganymede, also good series of
observations of Encke's and other comets. He has lately
made an attempt to induce astronomers to adopt 1925 as the
epoch for all star places deduced up to 1950; for this purpose
he has published tables for reducing places from each year
to 1925.
THE ORBIT OF SCHAUMASSE'S NEW COMET.—
Messrs. Kiess and Nicholson have found these elements: —
Perihelion passage, 1913, May, 17-91 G.M.T. ; Omega, 57°28';
Node, 317°0'; Inclination, 153°34'. Perihelion distance,
1-440. Ephemeris for Greenwich — Midnight, May 27th,
R.A. 18h 22m 8", N.Dec. 35°4l'; May 31st, R.A. 17h 22m 42s,
N.Dec. 39°5l'; June 4th, R.A. 16h 19m 13", N.Dec. 41°40';
June 8th, R.A. 15h 21m 52", N.Dec. 41°ll'; June 12th,
R.A. 14h 35m 48s, N.Dec. 39°17' ; June 16th, R.A. 14h l'n 24s,
N.Dec. 36°47'; June 20th, R.A. 13h 35m 56", N.Dec. 34°16'.
Nearest earth May 31st, when the distance is sixty-two
million miles ; it will probably then be of the eighth
magnitude.
BOTANY
By Professor F. Cavers, D.Sc, F.L.S.
CLIMATE CHANGE AND WOODLAND SUCCES-
SION.— In an interesting paper the Rev. E. A. Woodruffe-
Peacock (Joiim. of Bot., 1912) claims that historical records
of the former occurrence of vineyards in Southern England
are indicative of a warmer climate. Other evidence is seen
in the more open texture of oaks and pines found in the older
peat deposits as compared with the closer texture of the
stems found in the more recent peat. The peat deposits of
East Anglia are regarded as having developed in relation to
woodlands on adjoining higher lands, and the tree-remains
represent phases of migration of woodland on to the peat. It
is suggested in a general way that the tree-remains represent
periods — oak being the oldest"; ash, holly and elm the more
recent. On historical, floristic and faunistic grounds the
Scots pine may have always been indigenous in parts of
Lincolnshire, as also the beech, which comes in a later period
with a warmer climate.
A BRITISH FOSSIL SELA GIN ELLA.— Professor
Seward (New Phytologist, March, 1913) describes a fossil
Selaginella (Selaginellites Dawsoni) found in beautiful
preservation in the Fairlight Clay at the base of the Wealden
series at Ecclesbourne on the Sussex coast. The fact that
the genus Selaginella is now represented in the British flora
by a single species (S. spinosa), somewhat rare and chiefly
confined to hill regions, adds interest to this discovery of a
Wealden species which differs from S. spinosa, but shows a
close resemblance to the widely distributed recent species
S. rupestris — not found in Europe, however. The vegetative
parts are not sufficiently well preserved to show with certainty
whether the fossil species had one or two forms of foliage
leaves, but the two kinds of spores are extremely well
preserved and show the most minute markings on the spore
coat with great clearness.
June. 1913.
KNOWLEDGE.
219
FAIRY RING FUNGI.— Miss Bayliss (Jourtl. Econ.
Biol., Vol. VI) has found that the well-known " fairy ring "
fungi Marasmius oreades and Clitocybc gigantea are not
saprophytes, but are parasitic on the roots of grasses, which
they kill by the secretion of some toxic substance. The same
or some other secretion is toxic to the fungi themselves,
making them unable to grow in the same soil for three years
in succession, and hence producing the well-known develop-
ment of yearly widening rings. As compared with the
infected grass, that which lies just outside as well as that
inside the ring is stimulated into better growth by the greater
abundance of nitrogenous food which is made available by
the action of the mycelium of the fungi in secreting protein-
digesting ferments (proteolytic enzymes). The yearly increase
in the radius of the rings was measured — in the case of
Marasmius oreades it was found to be from six to fourteen
inches.
CAUSE OF LEAF-FALL. — From experiments made with
detached twigs of various deciduous trees placed in water in
a saturated atmosphere Varga (Oesterr. bot. Zeitschr.,
Band 61) has sought to establish a relationship between this
familiar phenomenon and the processes of transpiration and
photosynthesis influenced by various conditions of light and
temperature. He concludes from the results of his experi-
ments that (1) any decided checking of photosynthesis, either
from light conditions or from a deficiency of carbon dioxide,
brings about leaf-fall ; (2) any lowering of transpiration also
induces defoliation, but less rapidly than diminished photosyn-
thesis; (3) variation in the intensity and quality of the light
has no direct specific action upon leaf-fall ; (4) lower tempera-
tures are effective in producing leaf-fall through decreased
photosynthesis and transpiration only within limits which
allow the activities involved in the development of the
absciss layer — below these limits the leaves die, but cling
rather persistently to the twigs.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon.), F.I.C.
INSTITUTE OF METALS.— At the annual general meet-
ing of the Institute, on March 11th and 12th, 1913, the Report
of the Council was presented by the President. From this it
appears that there has been a steady increase in the number
of members, which has risen from three hundred and fifty-five
in 1908, to six hundred and fourteen in 1912.
Six papers were also read on this occasion by Fellows of the
Institute. These included a study of the "Corrosion of
Aluminium," by Dr. G. S. Bailey, in which it is shown that
the results obtained by acting upon the metal with acids or
alkalies afforded no definite indication of its behaviour in the
presence of water or solutions of salts. In the paper read by
Mr. Siemens upon " Metal Filament Lamps," an account is
given of the evolution of the processes of preparing the wire for
these lamps, descriptions of many of which have been given
in these columns. The general conclusion reached, is that it
is doubtful whether it will be possible to construct a much
more economical glow-lamp than the tungsten lamp, and that
further progress must be sought in the directions of the
improvement and cheapening of the electric supply. The
remaining papers by Mr. Gulliver, Messrs. H. & J. Primrose,
Mr. Hudson, and Mr. A. Philip are more purely technical in
character.
NEW GERMAN INK REGULATIONS.— An account is
given by Dr. Hinrichsen in the Chemiker Zeitung (1913,
XXXVII, 265) of the Prussian regulations for the official tests
of writing ink, which came into force last year. In these
regulations inks are classified into " documentary " and
" ordinary writing inks," and the methods for their analysis
and examination are outlined. For example, a " docu-
mentary " ink must contain at least twenty-seven grammes of
anhydrous gallotannic and gallic acids, with at least four
grammes of iron, per litre, and the ratio of tannin to iron must
lie within the limits of 4-5:1 and 6-75:1. Ordinary iron-
gall writing inks may contain less tannin, but must still have
the same ratios of tannin and iron.
Both kinds of ink must show no alteration in the ink-pot for
at least fourteen days, must flow readily from the pen, and
must give writing which after being exposed for eight days to
the air, is deep black, and can be washed with water and with
dilute alcohol.
In testing the permanency-of the writing, pieces of standard
paper are stretched in a frame inclined at an angle of 45°, and
a definite quantity of the ink is made to flow over this paper
from a pipette, which is placed in a rest on the frame, so that
it is always at the same angle. Simultaneously, parallel ink
bands are made upon the paper with a standard ink of known
composition, prepared in a definite manner.
The paper, with the colour bands of the two inks upon it, is
exposed for eight days in diffused daylight, and is then cut
horizontally into three strips. One of these is immersed in
water, the second in fifty per cent, alcohol, and the third in
eighty-five per cent, alcohol. In none of the strips should
there be any perceptible bleaching of the ink.
HARDNESS OF RAINWATER.— Rainwater is commonly
regarded as one of the purest forms of natural water, but this
is not always the case with the rain that falls in large towns
and especially in industrial centres. For example, some years
ago it was found that the rainwater in Paris was decidedly
hard, and the cause of this was traced to the dust from
macadamised roads, the salts in which had been taken up by
the rain during its passage through the air.
Another remarkable instance of hard rainwater has recently
been investigated by Dr. S. Wolff (/. Soc. Chem. Ind., 1913,
XXXII, 345). The water used in some large works outside
Manchester has frequently given trouble on account of its
hardness, though consisting largely of rainwater collected from
the roofs of the buildings. All the samples of the rainwater
examined prior to their entering the reservoir were found to
be decidedly hard and to give an alkaline reaction. In some
of them the proportion of dissolved calcium salts was so great
that a scum could be formed by blowing into the water.
A specimen of rainwater collected directly from the roof
contained one hundred and seventy parts of total solids per
one hundred thousand, and had a total hardness of 87-2 and
temporary hardness of 15 '75.
In the discussion upon this paper it was mentioned by Mr.
W. H. Coleman that much of the coal used in the neighbour-
hood of the works came from the Bradford Colliery, and that
this coal was rich in crystallised carbonate, and it was
suggested that the smoke from this coal might convey calcium
compounds into the air. Apart from this, a considerable
quantity of flue dust must be blown up the chimneys into the
air, and a considerable quantity of this must settle upon the
roofs ; whence some of its soluble constituents would be
dissolved by the falling rain.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
OLD RED SANDSTONE AT SOUTHALL.— The in-
teresting discovery of Palaeozoic rocks made by E. Proctor
in a boring at Southall is described in the current volume of
The Quarterly Journal of the Geological Society. The plat-
form of old rocks was struck at a depth of one thousand one
hundred and thirty feet, and continued to one thousand two
hundred and sixty-one feet, the total depth of the boring.
After two hundred and sixty-two feet of gault, the boring
entered red and green mottled clays and sandstones, with
occasional bands of fine conglomerate. On breaking up the
cores remains of fossil fish were found in a marked type of
rock occurring in thin bands and consisting almost entirely
of organic remains associated with rounded and subangular
grains of quartz. The fossils, as determined by Dr. Smith
Woodward, consist of scales and teeth of Holoptychius and
plates of Bothriolepis, both of which are characteristic of
the Upper Devonian or Old Red Sandstone. This discovery
creates a probability that other but unfossiliferous Red Rocks
found in other borings in the London Basin are of the same age.
220
KNOWLEDGE.
June, 1913.
RAISED BEACHES AND PALAEOLITHIC MAN.— In
the April Geological Magazine Mr. H. Dewey describes the
raised beach of North Devon and discusses its relations to
other Pleistocene deposits and to Palaeolithic man. The
raised beach forms a shelf and notches the cliffs about ten to
fifteen feet above sea-level. Between Croyde Sand and
Saunton Down the beach lies on a shelf, and is overlaid by a
variable thickness of current-bedded sand, the contained
shells of which indicate a warm temperate climate. The
raised beach deposit consists of pebbles of slate, sandstone,
vein-quartz, quartzite, and chalk-flints. Erratic boulders of a
red granite lie on the platform. The granite closely resembles
a gneissose granite from Ross-shire ; and if this identification
be correct, ice is the only conceivable transporting agency.
The sand is overlaid by a bed of " head," which in turn is
covered by a bed of large rounded stones. A bed corre-
sponding with the latter, occurring at Fremington, contains
glaciated stones in a brown loamy clay, and indicates an
arctic climate during its formation. A similar bed of
glaciated stones overlying " head " was discovered by Mr.
Barrow in the Scilly Isles. In the Coombe rock of Southern
England and France, which is equivalent and contemporan-
eous to the "head" of Devon and Cornwall, Palaeolithic
implements of Mousterian type have been found.
Mr. Dewey comes to the conclusions that the deposits over-
lying the raised beaches were formed during a period of
variable climate — arctic at first, then warm temperate, finally
reverting to arctic — and that early Palaeolithic man lived
during the inter-arctic period. He is later than the chalky
boulder clay and the raised beach, and earlier than the
boulder clay of Glamorgan and South Ireland.
QUANTITATIVE STUDY OF ACTIVE VOLCANOES.
— The great quantitative geological investigations which we
owe to the Geophysical Laboratory of the Carnegie Institute
at Washington are now being supplemented by a study of the
physics and chemistry of active volcanoes (Year Book No. 11,
1912). The crater of Kilauea in Hawaii is the one selected
for this purpose. During the past summer it was found
possible to descend into the crater and collect the volatile
ingredients directly from the lava. These gases were
collected and sealed in glass tubes without having come into
contact with the air at all, and sent to Washington for
detailed study. A very important observation is, however,
available, and that is that the temperature of the lava in the
active basin varies from day to day, and that this variation
depends on the quantity of gas emitted. The temperature rises
with an increase of gas emission, and falls when the volume
of gas diminishes.
The composition of the smoke cloud above the volcano,
which contains much non-gaseous matter, was also studied,
and samples of the liquid lava were taken directly from the
molten lake. It is hoped to determine the character of the
chemical reactions within the gases, between the gases and
the liquid lava, and between the gases and the air. Arising
out of the recent contention of Briin and others that volcanic
eruptions are essentially anhydrous (see ■ Knowledge,"
April, 1911, p. 352), it is mentioned that from one of the gases
collected directly from the boiling lava no less than half a
pint of water was condensed on cooling.
METEOROLOGY.
By William Marriott, F.R.Met.Soc.
DEATHS BY LIGHTNING.— Most people imagine that
the number of persons killed by lightning each year is very
great. This impression is largely due to the lack of reliable
information and to the inherent dread of thunderstorms, and
is far from being correct. Dr. A. Jex-Blake, in a recent course
of lectures delivered before the Royal College of Physicians
on " Death by Electric Currents and by Lightning," gave
some statistics on the subject from which he showed that during
the ten years 1901-1910, the Registrar-General had reported
one hundred and twenty -four fatal instances in lightning
stroke in England and Wales — one hundred and eight in men
and sixteen in women — a yearly average of only 12-4 deaths,
or 0-36 per million living. In the twenty-nine years 1852-1880
there were five hundred and forty-six such deaths, the yearly
average for that period being 18-8, or 0-88 per annum per
million living. The number of these deaths varied widely in
different years ; three people were killed by lightning in
1863 and forty-six in 1872. The annual death-rate from
lightning also varies widely in different parts of England. In
the north Midlands from 1852-1880 it was 1-8 annually per
million living, in the Metropolitan district only 0-13 (Lawson)
— a figure that should be of comfort to anybody who is in
London during a thunderstorm. On the Continent much
higher yearly death-rates are found. In Hungary the annual
death-rate from lightning is said to be sixteen per million
living (Milham) ; in Styria and Carinthia about ten per million ;
in Prussia 4-4; in France and in Sweden three; in Belgium
two, so far as the imperfect statistics available go (McAdie
and Henry). Inthe United States of America the annual death-
rate per million is high — about ten — in consequence of the
frequency of thunderstorms on the one hand and of the large
percentage of the inhabitants engaged in outdoor labour on
the other ; about seven hundred or eight hundred deaths
from lightning were estimated to occur in the United States
every year by Henry in 1900 in a population of seventy-six
millions.
Many more people are struck by lightning than are killed.
For example, Jack records an instance in which a church was
struck : three hundred people were in it, one hundred were
injured and mostly made unconscious, thirty had to take to
their beds, but only six were killed. Weber gives an account
of ninety-two people struck in Schleswig-Holstein : ten
were killed, twenty paralysed, fifty-five stupefied, and seven
only slightly injured. In 1905, a tent with two hundred and
fifty people in it was struck, and sixty were left on the ground
in various states of insensibility ; one was killed outright,
another breathed for some minutes before dying, the rest
recovered. As many as eleven and eighteen persons have
been killed bj*'a single stroke of lightning. Vincent mentions
a stroke thMt threw down one thousand two hundred and
killed five hundred and fifty-six out of a flock of one thousand
eight hundred sheep. Dechambre believes that children are
perhaps less liable to be struck than adults ; but statements
such as these are really not capable of proof or disproof.
STORMS ON THE ATLANTIC, JANUARY, 1913.—
The month of January, 1913, was probably the stormiest
month on record on the North Atlantic Ocean. Mr. R. E.
Harris has given an account of the storms of this month,
together with some synoptic charts over the North Atlantic at
Greenwich mean noon, and also barograms from several
vessels.
During the first half of the month several unusually severe
storms crossed the North Atlantic, the most severe of which
can be traced on the synoptic charts from the 8th to the 11th.
This storm was only a moderate depression with two centres
at noon of the 8th, the lowest barometer at the primary centre
over New York being 29-60 inches. At the same time a
severe storm was central near latitude 49° N., longitude
25° W., and was causing winds of force eight to twelve
(Beaufort scale) over a wide area north of the Azores between
the fifteenth and forty-fifth meridians. By noon of the 9th a
rapid development in the western storm had occurred, and it
was central near latitude 45° N. and longitude 48° W., with
lowest barometer 28-72 inches. Winds of force seven to
twelve were prevailing west of the fortieth meridian and north
of the thirty-fifth parallel. During the night of the 9th and
10th the storm was at its height, and remarkably low
barometer readings were recorded, the lowest, 26-96 inches,
being registered on the SS. Manchester Inventor, at 1 a.m.,
on the 10th, at 52° N., 25° 30' W. This is probably the
lowest reading ever made on the North Atlantic. By noon
the storm was central near 51° 30' N., 27° W., with lowest
barometer 27-76 inches. Winds of hurricane force were
experienced by many vessels north of the fortieth parallel,
between the forty-fifth and fourteenth meridians. Within
this area ten ships reported winds of force twelve, thirteen
June, 1913.
KNOWLEDGE.
221
force eleven, five force ten, and nine force nine, out of a total
of forty-seven. By noon of the 11th the storm was central
near 56° N. and 15° W., and winds of force seven to eleven
were prevailing over the ocean north of the fortieth parallel
and east of the forty-fifth meridian. Severe gales occurred
over the British Isles.
LOWEST BAROMETER RECORDS
with the above remarkably low
reading of 26-96 inches it may
be of interest to give what is,
so far as is known, the next
actual lowest barometric pres-
sure which has been observed in
any other part of the world, viz.,
27-135 inches on September
22nd, 1885, at False Point, on
the coast of Orissa, India. In
the British Isles the lowest
recorded barometric pressures
have been: — 27-332 inches on
January 26th, 1884, at Ochter-
tyre, Crieff; and 27-380 inches
on December 8th, 1886, at
Belfast.
-In connection
VIOLENT UPRUSHES IN
CUMULUS CLOUDS.— Every-
one who has carefully watched
clouds is familiar with the
peculiar boiling and tumbling
of large cumulus clouds, their
formation of new heads, and
the other evidences they often
give of violent motions and an
explosive-like turbulence. The
late Dr. W. von Bezold suggested
that these movements indicate
that there is a source of power
within the cloud itself, and he
ascribed this power to the latent
heat set free by the more or less
sudden condensation of a super-
saturated vapour, or the sudden
freezing of undercooled water-
drops.
Professor W. J. Humphreys has recently investigated this
subject, and he has come to the conclusion that the difference
in temperature between the free air and the interior of large
cumulus clouds at the same level is the
real cause of the violent uprush and turmoil
in their centres. He is also of opinion
that most of the electrical and other energy
of the thunderstorm comes directly or
indirectly from the latent heat of conden-
sation set free within the mass of turbulent
cumulus clouds.
PHENOLOGICAL OBSERVATIONS,
1912. — At the meeting of the Royal Meteor-
ological Society on April 16th Mr. J. E.
Clark and Mr. R. H. Hooker presented
their report on the Phenological Obser-
vations for the year ending November,
1912. This dealt with the dates of the
first flowering of certain plants, the song
and migration of birds, the appearance of
insects, and the yield of farm and fruit
crops. The chief factors affecting the field
crops were probably the dry warm April
and May, followed by the cold, wet, sunless
summer. The spring was perhaps the more
important of the two : it affected the corn crops and the hay.
All the crops in the United Kingdom were below the average
of the preceding ten years, although in Great Britain alone
meadow hay was a little better than usual, and hops were
Figure 228.
A new model Microscope.
Figure 229.
A Rhipicephalus from Australia.
also above the mean by fully twenty-three per cent. The
harvest of 1912 must be classed as very deficient, and one of
the worst experienced for many years.
H A R V EST WEATH ER FO RECAST.— The Meteorological
Office will be prepared, from June 1st to September 30th, to
supply forecasts of weather by telegraph, to farmers and other
persons desirous of receiving' them, upon payment of the cost
of the telegram. The forecasts
are drawn up each week-day,
at 2.30 p.m., and refer to the
probable weather during the
fifteen hours from 6 a.m. to 9
p.m. on the next day. A note
as to the further outlook is
given when possible. Applica-
tions for the forecasts should
be sent to the Director, Me-
teorological Office, South Ken-
sington, London, S.W.
MICROSCOPY.
By F.R.M.S.
A NEW MODEL MICRO-
SCOPE.— Figure 228 repre-
sents a new pattern microscope,
designed by Mr. E. Leitz, which
combines in itself features of
both the English and Conti-
nental models. There is a
tripod base which gives rigidity
in the horizontal as well as in
the vertical position. A curved
limb allows of additional work-
ing space on the stage, which is
of the square fixed type, though
a detachable mechanical
arrangement may be added.
The sub-stage has centring
screws controlling the conden-
ser sleeve which is of the
standard gauge of the Royal
Microscopical Society, while
the fine adjustment is of
the type originally introduced into the Leitz Continental
Microscopes and consists of a cam and worm screw
continuous motion.
AN AUSTRALIAN TICK.— A short
time ago two small " insects " were sent to
me by a friend in Devonshire, who said
they had been found on the dress of a
child, whose mother, being unable to rec-
ognise them, feared they might be some
species of Citnex, and was anxious to
know if this was so, and where it was
likely they came from. On placing them
under the microscope I saw at once that
they were Ticks, but were so flat and
so dry that I concluded they had died
of starvation, and had been dead a long
time. They measured -18 inch in extreme
length and were lemon - coloured, with
purple-brown markings and spots. After
careful examination and comparison with
the figures and descriptions given by
Neumann in his " Revision of the Ixodes,"
I determined them to belong to the
genus Rhipicephalus, and therefore cer-
tainly not British ; but as to species they
did not exactly agree with anything figured
either by Neumann or by any other authority consulted.
Having only two specimens I was unwilling to dissect more
than one, and having detached and prepared its capitulum I
was successful in this instance in getting a clear view of the
cc
222
KNOWLEDGE.
June, 1913.
chelicerae, though, unfortunately, not also of the
hypostome. On looking through the mounted
specimens of some fifty species in my cabinet
I found that the chelicerae closely resembled
those of a Tick sent to me from Brisbane as
having been found on a dog in the neighbour-
hood of the Filbert River in Queensland. How,
then, could it have been found in Devonshire ?
Further enquiries elicited the fact that the
child on whose dress these Ticks were found
had shortly before been playing on a fur rug
made from the skins of Australian Dingoes, and
there seemed no doubt that these Arachnids had
been imported in this. D „ .
K. 1 . iw.
A PORTABLE MICROSCOPE.— It is an
axiomatic truth that the Continental form of
microscope, with its short tube, lends
itself to portability better than the
English one, with its long tube and
extended base.
Messrs. Leitz, in 1899, introduced a
portable model, in which a closing V
was substituted for the horseshoe foot ;
but in 1901 further improvements were
made by adopting the well-known plan
of pivoting the stage, so that it could
be turned round into the plane of the
optic axis ; thus the whole microscope,
although of full size, could be folded
up into a compact block, which could
be packed in a small box (see
Figure 232).
Their later microscope model with a
horizontal pinion fine-adjustment (in-
troduced in 1903) has now been
adapted to this portable form, and one
has just been made in which some
alterations have been adopted.
First, the stage has been made on my
horseshoe plan, and fitted with a sliding
bar (Figure 231). It measures 13 X9cm. ;
rather a contrast to the 6X4 cm. stage,
at one time an extreme size for a
Continental microscope !
Attached below the stage is the
usual spiral focusing mechanism carrying
a sub-stage ring, which has a small amount
of play for centring by
means of a spring
opposing two screws.
A tube sliding into this
ring carries an achro-
matic condenser and an
iris diaphragm ; below
this is a turn-out ring,
with a rather deep cell,
to hold screens, stops,
and so on.
Secondly, the pillar
which carries the
microscope is fitted
with a conical pivot,
so that the V-foot may
be turned round in
order that the toes of
the V may face back-
wards instead of for-
wards (Figure 231).
The rotating foot was
first made by John
Cuff, 1750. Previously,
when the microscope
was inclined it was
found that its stability Figure 232.
was seriously impaired, The Microscope folded.
Figure 230.
Chelicerae of the
Rhipicephalus.
Figure 231.
A Portable Microscope.
so much so that when a horizontal position
was reached the microscope fell over ; but
now, when the foot is rotated backwards, the
microscope is perfectly stable. Figure 233
shows the instrument holding an Abbe camera
in a position for drawing at the side, an increase
of stability being required on account of the
weight of the large mirror on the top of the tube.
In this case the V-foot is rotated half-round.
The draw tube has been increased in length, so
that with eighteen millimetres for the objective
slide or rotating nosepiece, a total of two
hundred and eleven millimetres has been ob-
tained. There are some objects which require
the whole of that length, even with a short tube
objective.
In Figure 231 the instrument is seen fitted
with one of Messrs. Leitz"s eyepieces,
with rotating eye-lenses (introduced
1899) ; the same field lens does duty for
both. This is a most convenient and
time-saving device. One is a No. 2
(X6), the other a No. 5 (X12). The
corrections of these eyepieces are very
perfect.
The objectives, six in number, viz.,
Nos. 1, 2, 3a, apo. 8 mm., 6a and apo. A
1-4 N.A., are all supplied with slides,
and fit, while attached to their slides, in
a separate box : this plan saves much
time in screwing and unscrewing and
packing them away in their own brass
boxes. This box is itself packed in the
same case as the microscope, as also
are the six brass boxes for the objectives,
and an oil bottle.
In addition to the rotating eyepiece,
there are Nos. 2 and 3 Huyghenian, a
micrometer eyepiece, and an 8, a 12 and
an 18 compensating eyepieces. A polariser
and analyser has also been added, the
whole thus forming a fairly complete
microscopical outfit.
Edward M. Nelson.
PHOTOGRAPHY.
By Edgar Senior.
IMPERFECT FIX-
ING.— Hypo " Sodium
Thiosulphate " is in-
variably used as the
fixing agent for both
negatives and prints.
Its action depends upon
the formation of a
double salt with the
unaltered silver salt left
in the film, and when
the hypo is present in
sufficient excess the
double salt formed is
highly soluble in water
and diffuses readily out
of the film in washing.
If, however, the fixing
bath is too weak, or the
plates or prints are
removed too soon, then
imperfect fixing results,
owing to the formation
of a double salt which
is almost insoluble in
water. This may be
shown as a simple test-
tube experiment by
Figure 233. The instrument with
draw tube increased in length and
fitted with an Abbe camera.
June, 1913.
KNOWLEDGE.
223
taking a solution of silver nitrate and one of hypo, when,
on adding them together in such a manner that the former
is present in excess, a white precipitate, which rapidly turns
brown and finally black, is the result, the reaction being
expressed by the following equations : —
2AgNOa + Na2SaO» = AgaSaOa + 2NaNO:i.
Then
AgaSaO, + HaO = AgaS'+ H2SO4.
By the addition of hypo in excess, however, the white pre-
cipitate first formed is readily dissolved and a perfectly clear
solution results. Therefore care should be taken to have the
fixing bath sufficiently strong and to allow the plates or prints
to remain in long enough to ensure perfect fixation. In
other words, to ensure the formation of the double thiosul-
phate of silver and sodium, which is highly soluble, a reaction
expressed by the equation : —
2AgBr + 3Na2SaO:! = AgsNa4(Sa08)s + 2NaBr.
ACID FIXING
BATHS.— The use
of an acid fixing
bath has certain
advantages over that
of a plain solution
of hypo in water,
inasmuch as the
bath keeps clean
for a much longer
time and the plates
are quite free from
any deposit or stain
in the film. Their
preparation requires
care to avoid any
precipitate of
sulphur taking place
due to decomposi-
tion of the hypo by
the acid. A very
good formula for ■»#■* — .•■ .----•
such a bath, " origin-
ally given by Mr. p^ j5
Sandell for fixing
his double- and FlGl!RK 2i4" Photographic test of
triple-coated
plates," is the following : —
Hypo ... ... ■•■ ■•• ••• 7 ounces
Soda Sulphite 1 ounce
Water ... ... ... ... ... 20 ounces
Strong Sulphuric Acid 1 drachm
After the hypo and soda sulphite are dissolved the
sulphuric acid is added in drops at a time, stirring all the while.
Such a fixing bath keeps quite a long time and may be
diluted or not as thought desirable. Another bath, containing
meta-bisulphite of potassium, is as follows : —
5 ounces
20* "
Hypo
Potassium meta-bisulphite
Water
An acid fixing bath, containing common alum, can be prepared
by taking certain precautions in mixing. The following will be
found a very good formula : —
Hypo ... ... ... ... ••• 4 ounces
Soda sulphite 1 ounce
Common alum ... ... ••• ••• i „
Tartaric acid 60 grains
Water ... ... ... ••• ••• 20 ounces
The ingredients must be dissolved in the order given, as,
supposing the soda sulphite were to be added last, it would be
found that the alum and tartaric acid would react with the
hypo and a precipitate of sulphur would result.
A good plan is to dissolve the hypo and sulphite in a part of
the water and the alum and tartaric acid in the remainder.
The alum is then added to the solution of hypo and soda
sulphite and finally the tartaric acid solution is poured slowly
into it, stirring all the while. A precipitate which first forms
will be found to dissolve up completely, and the acid solution
will remain quite clear. This fixing bath possesses consider-
able hardening properties when freshly made, which, however,
decrease rapidly by keeping.
TESTING DARK - ROOM LIGHT FILTERS.— One
frequently sees an otherwise good negative completely spoilt
through undue exposure of the plate during manipulation to
the light from the dark-room lamp. If we remember that
there is probably no such thing as an absolutely safe light — it
simply being a question of the length of time a plate may be
exposed without showing any effect due to this cause — it is
evidently advisable that some kind of test should be made to
ascertain it. Of course, the spectrum test is valuable in
showing the region of the light transmitted by the material
used as a filter, but then the general sensitiveness, as well as
the spectrum sensi-
tiveness of the
emulsion, has to be
taken into consider-
ation also. And it
is found that a light
which is perfectly
safe to employ with
a plate of low sensi-
tiveness would not
be so for one of the
opposite nature. In
fact, a plate may be
orthochromatic, but
its general sensitive-
ness so low that it
may be developed in
a yellow light, with-
out any bad result
following from so
doing. The question
naturally arises then
as to what test
should be applied to
ascertain the safetv
the safety of dark room light filters. of otherwise of the
medium in use for
the purpose of filtering the light through. The one employed by
the writer is due to Sir William Abney, and consists in exposing
a plate behind several different kinds of coloured glass, paper,
or fabrics to the light used as the source of illumination for
periods varying with the nature of the emulsion on the plate.
A test of this kind is shown in Figure 234, the material used
being (a) canary medium, (6) cherry fabric, (c) orange paper.
These were fastened together and placed upon a piece of clear
glass in a printing frame, and a special rapid gelatine plate,
225 H and D, laid upon them. The whole was then exposed
to the light from a sixteen-candle power incandescent electric
lamp for a period of two minutes at a distance of two feet
from the light. The plate was then developed in darkness, the
time allowed being five minutes. Examination showed that
practically no action had taken place upon that part of the
plate under the orange paper, while the cherry fabric had
allowed sufficient light to pass to cause considerable action on
the surface beneath it, while that part of the film protected by
the canary medium was, as might be expected, practically
black. Instead of fixing the image, the film was simply
washed and then placed in a solution of bichromate of
potash, made acid with sulphuric acid. This quickly dissolved
out the reduced silver, and after a thorough washing in
running water the plate was brought into the light and
redeveloped with amidol. By adopting this method the
necessity of making a transparency in the usual manner is
done away with and we at once get the relative effects pro-
duced shown in their correct aspect of light and shade, and
the test furnishes the information that one thickness of orange
paper employed in front of a sixteen-candle power electric
lamp would practically afford such safety that a gelatine plate
C
224
KNOWLEDGE.
June, 1913.
of 225 H and D might be exposed at a distance of two feet
for two minutes to the light transmitted by it without
showing any fog on that account. Tests of this kind are
valuable in conjunction with spectroscopic ones from the
quantitative estimation of the time required to produce any
action. Of course, the time could be still further prolonged
by exposing further away, and so taking advantage of the
greater distance. But two minutes are ample for all practical
purposes, and by keeping the developing dish covered during
development no trouble could possibly occur through any
fault of the dark-room light. Unfortunately, orange paper
varies very much in colour as well as thickness, but that which
is fairly stout and of a dark tint should be chosen, and then
tested after the manner described. It will be noticed that the
cherry fabric is rather uneven in texture and also has a good
number of pin-holes in it, so that either two thicknesses would
have to be used or a combination made with canary medium,
when a fairly safe light would result for plates of average
rapidity.
PHYSICS.
By Alfred C. G. Egerton, B.Sc.
THE HALL EFFECT. — Metals have the power of con-
ducting electricity and also heat ; their conductivity, however,
varies with the nature of the metal ; some metals, such as
tellurium, are feeble conductors, others, such as copper, offer
very low resistance indeed. The connection between con-
ductivity of electricity and that of heat is not at once evident,
though on the whole the thermal conductivity varies similarly
to the electrical with the nature of the metal. Electricity,
according to modern views, is conveyed along a conductor by
the electrons which pass from atom to atom. Heat is
conveyed as an increase in the kinetic energy of the molecules
of the substance ; but since the agination of the molecules
increases, so does the agitation of the particles contained
within them, viz., the electrons, and part of the thermal
energy conveyed along the conductor is due to the increased
kinetic energy of the electrons. This is especially the case for
the metals ; substances, such as sulphur, which are bad
conductors, conduct heat chiefly by the motion of the
molecules. It is possible to calculate approximately from
such considerations what the ratio of thermal conductivity to
electrical conductivity should be, and the ratio «r/<r at 10° to the
ratio KJa at 18° should be constant and have the value 1-28.
The results of experiments show that such a ratio is
approximately constant for many different metals — a
remarkable confirmation of the theory.
Now if electricity is conveyed along a wire by the free
electrons which carry a negative charge, a magnetic field
should deflect such electrons across the breadth of the con-
ductor, and so one side will acquire a negative charge of
electricity. At the same time a diffusion of such charged
particles will take place from crowded parts to those less
crowded, and equilibrium will be attained when the effect due
to diffusion counterbalances that due to the deflection of the
electrons by the magnetic field, a difference of potential
between the upper and lower edges of the conductor being
the result. Such a difference of potential was observed by
Hall in 1879, and has since been studied by Nernst and
others. Experiments have been very difficult, as several
effects come into play besides the Hall effect.
Kammerlingh Onnes, of Leyden, whose experiments on
liquefaction of gases are well known, has recently investigated
the Hall effect at very low temperatures. The effect obtained in
the case of bismuth can be divided into two components : the
effect due to the magnetic field, which always gives a negative
charge, due to the deflection of the electrons ; the other effect
is a thermal effect inversely proportional to the absolute
temperature, which may reverse the sign of the charge due
to the magnetic field. Results of considerable importance to
the electron theory of metallic conduction may be expected
from such experiments.
THE ROYAL SOCIETY'S CONVERSAZIONE.— On
May 7th the Royal Society held its conversazione, at which
many interesting exhibits were on view. Among such exhibits
may be mentioned the new lines which Professor Fowler has
found in the spectrum of hydrogen. Lines which have only
previously been seen from investigations of the spectrum of
the stars have been found when a very strong condenser
discharge is passed through a mixture of helium and hydrogen.
Another interesting exhibit was the micromanometer of Mr.
Fry, who arranges a stretched membrane so that its movement
twists a mirror suspended in a special manner : the pressure
differences being indicated by the deflection of a spot of light,
a difference of pressure of one-millionth of a millimetre of
mercury can be detected.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A.
SPOTTED NEGROES.— Q. I. Simpson and W. E. Castle
put on record an interesting peculiarity in human skin colour,
'" which made its appearance as a mutation or sport in a negro
family of the southern United States some sixty years ago, and
has shown itself fully hereditary through two generations of
offspring." The peculiarity is " piebaldness," the dark skin
being spotted with white in a fairly definite pattern. The
original ''mutant" was born in 1853, and her parents were
normally coloured negroes. She married a normal negro, and
had fifteen children, all of whom are living. The spottedness
behaves like a Mendelian character — as a simple dominant,
" the only peculiarity of the case being the excess of spotted
grandchildren over the expected one-half." Some of the
spotted descendants are now connected with " museums,"
and the authors note that the piebaldness, being an economic
asset, is not likely to interfere with their racial increase.
CLIMBING FISHES.— It is well-known that the tropical
fish, Periophthalmus, like its relative Boleophthalmus,
spends hour after hour out of water, squatting on the mud by
the sides of the tropical estuaries, or even climbing up on the
roots of the mangrove trees. But such climbing powers as
Periophthalmus possesses are far surpassed by a catfish
Arges marmoratus, which lives in the torrential rivers of the
Andes, where there is a rapid succession of falls, cascades,
and pot-holes. Under usual conditions A rges is a clumsy and
awkward swimmer, but for creeping and climbing in the
torrents it is wonderfully adapted. It anchors itself by its
suctorial mouth, and works itself upstream with the help of a
ventral bony plate bearing the ventral fins and equipped with
strong muscles which move it backwards and forwards. The
plate is studded with small sharp teeth pointing backwards.
The fishes climb up the smooth water-worn surfaces of deep
pot-holes, and have been known to ascend eighteen feet with-
out a slip or fall.
NOTICES.
ROYAL INSTITUTION.— The President has nominated
the following gentlemen as Vice-Presidents for the ensuing year:
— Dr. Henry E. Armstrong, the Right Hon. A.J. Balfour, J. H.
Balfour Browne, Esq., Sir William Crookes, Dr. Donald W. C.
Hood, the Right Hon. Sir James Stirling, Sir James Crichton-
Browne (Treasurer), and Alexander Siemens, Esq. (Secretary).
SECONDHAND BOOKS ON NATURAL HISTORY.
— More than nine hundred and fifty books on Natural
History are included in Messrs. Henry Sotheran & Co.'s
recent catalogue, numbered 736. The prices appear to
be most reasonable and the volumes are on view at
43, Piccadilly.
THE FACE OF THE SKY FOR JULY.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 41.
Date.
Sun.
R.A. Dec.
Moon.
R.A. Dec.
Mercury,
R.A. Dec.
Venus.
R.A. Dec.
Jupiter.
R.A. Dec.
Uranus.
R.A. Dec.
Greenwich
Noon.
h. m. 0
6 51 "6 N.22"9
7 12*2 22 -4
7 32'6 91*7
7 52*7 20'9
8 1 2 '7 ?o"o
8 32-4 N.i8-o-
h. m. o
7 107 N.27*3
it 53-3 N. o'6
16 i6'4 S, 26'2
20 55'3 S. 21 -i
0 34 '0 N. 5*0
4 39-5 N.27'2
h. m. 0
3 41-4 N. 18-7
g o'2 i6'4
9 i2'3 14*4
9 18-5 12-7
9 16-5 11*7
9 7*2 N. 1 1 '6
h. m. 0
3 38-9N.i6-i
3 58"6 17-2
4 i9'2 i8"3
4 40*5 19-2
5 2 "5 20 'o
5 25"! N.20'6
h. m. 0
18 56*9 S.22"9
18 54*2 93*0
18 51-4 23*0
18 48-8 23-1
18 46*2 23*2
18 43'9 S.23'2
h. m. 0
20 36*3 S.i 9 '3
20 35*6 i9"3
20 34"8 19*4
20 34'o i9"4
20 33-2 19-5
20 32-4 S.i9'5
■» 29
Table 42.
Date.
Sun.
PPL
Moon.
P
Jupiter. .
P P I, I, T T
12 12
Greenwich
Noon.
00 0
- i'4 +3'3 07-6
+ °'9 3'8 3''5
3'2 4'3 325'3
5'4 4'8 259-1
7*6 s'2 ig-^'o
+ 9'6 +5-6 126-8
O
+ 6*5
+ 21 '9
+ 9'5
-15*0
— 21 "7
- 7'5
030 ° h. m. h. m.
— 6*9 —1 '6 83*0 2:'i6*4 7 34 e 2 35 e
6"b i"6 153*2 298*4 5 39 e 11 37 r
6*3 1 '6 923*3 33°*4 3 44 <? *° 45 e
6'o i*6 293*3 2'3 11 40 c 9 52 e
5*8 i"6 3'3 34M 9 45 e 9 0 e
-5*5 -i'6 73'2 65-8 7 51 e S 7 e
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Jupiter, Lx refers to the
equatorial zone ; L2 to the temperate zone ; Ti, T2 are the times of passage of the two zero meridians across the centre of the
disc ; to find intermediate passages apply multiples of 9h 50im, 9h 55|m respectively.
The letters m, e, stand for morning, evening. The day is taken as beginning at midnight.
The Sun has now commenced his Southward march.
Sunrise during July changes from 3.49 to 4.23 ; sunset
from 8.18 to 7.49. Its semi-diameter increases from 15' 45"
to 15' 47". It is at its greatest distance from the Earth at
midnight on July 3rd. Outbreaks of spots in high latitudes
should be watched for.
Mercury is an evening star, reaching East Elongation on
July 7th, when it is 16° from the Sun. Illumination one-half
on 1st, one twenty-fifth on 30th. Semi-diameter increases
from 3i" to 5i".
Venus is a morning star, reaching West Elongation July 4th,
when it is 46° from the Sun ; 7?° South of Moon on 30th.
Semi-diameter diminishes from 12" to 9". At beginning of
month one-half of disc is illuminated ; at end of month
five-eighths. Being South of Sun till the 24th, it is less well
placed for Northern observers than it was as an evening
star ; after that its position is favourable.
The Moon.— New 4" 5h 6m m ; First Ouarter 10d 9h 37m e ;
■Full 18d 6h 6mm; Last Quarter 26d 9h 59m m. Perigee
6d \2h e, semi-diameter 16' 24". Apogee 22d 7h e, semi-
diameter 14' 46". Maximum Librations, ld 6° E, 3d 7° S.,
14d 5° W., 16d 7° N., 28d 7° E., 30d 7° S. The letters
indicate the region of the Moon's limb brought into view
by libration. E. VV. are with reference to our sky, not
as they would appear to an observer on the Moon. (See
Table 43.)
Table 43. Occultations of stars by the Moon visible at Greenwich.
Date.
Star's Name.
Magnitude.
Disappearance.
Reappearance.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.-
"9*3-
h. m.
h. m.
fuly I
BAC1170
5 "5
1 38 in
1190
2 12 in
201°
,, I
26 Tauri
6 6
—
2 42 III
289
,, I
BD + 23°569
6-8
—
—
3 low
267
„ 6 ...
8 Leonis
5*9
8 38.
in
9 28 e
300
„ 8
82 Leonis
67
9 3''
126
—
„ 8
83 Leonis
6'3
10 16 e
'49
—
—
„ 13
b Scorpii
47
11 27 e
108
—
—
„ 21
39 Aquarii
6-2
0 50 in
349
1 20 in
3°5
„ 23
BAC 47
7 '3
—
—
10 44 e
3°S
,, 23
BAG 57
6-3
10 20 e
72
II 22(
226
,. 25
70 Piscium
7-8
—
—
0 42 in
3°5
„ 25
e Piscium
4 5
0 18 111
38
1 22 111
254
,, 26
27 Arietis
64
10 43 i
67
11 37 e
243
,, 28
BAC 105s
6-9
—
—
0 40 111
187
„ 28
66 Arietis
6-1
2 5 m
37
3 0 m
272
„ 2g
X Tauri ...
5"3
I 18 111
88
2 1 2 in
235
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
225
226
KNOWLEDGE.
June, 1913.
Mars is a morning St;ir, but not yet well placed for
observation.
Jupiter is in opposition on July 5th. Polar semi-diameter,
21*".
Table 44.
Day.
West.
East.
Day.
West.
East.
July 1
32
3
4
Julv 17
1
O
324
,, 2
3
1
124
,. 18
2
U
134
» 3
1
J
234
„ 19
12
O
34
,. 4
2
J
4>3
„ 20
u
3124
» 5
14
J
3
2«
.. 21
312
0
,, 6
43
J
12
,, 22
342
■0
1
» 7
4321
J
». 23
43i
u
2
„ 8
432
3
,, 24
4'
u
32
., 9
43
J
12
., 25
42
u
'3
„ 10
41
0
23
,, 26
412
u
3
,, 1 1
42
■J
13
., 27
4
0
3'2
» 12
41
)
3
2«
„ 28
43'
0
>. 13
©
412
,, 29
324
0
1
,, 14
312
^
4
,, 3°
3'
(J
24
1. '5
32
J
14
>■ 31
w
24 3« :
,, 16
3
'J
24
I*
Configuration at llhe for an inverting telescope.
Satellite phenomena visible at Greenwich, ld 2h lmm I. Oc.
R., 8h44me I.Sh. I., 8h 49me I.Tr. I., llh2me I. Sh. E.. llh T"e
I.Tr. E.; 2d 8h27mi; I. Oc. R.;4''2h \9™m II. Sh. I.. 2" 23mm
II. Tr. I.; 5d 8" 29rae II. Oc. D., llh 15m 38s II. Ec. R. ;
6d10h19mlII.Tr. E., 10h27m III. Sh. E. ; 8d lh 26mm I. Oc. I)..
3h 45m 52" I. Ec. R., 10h 33me I. Tr. I., 10h iSme I. Sh. I. ;
9d Oh 51ram I. Tr. E . Oh 56"'/« I. Sh. E., 10h 14" 26'e I. Ec. K. ;
12d 10h 42me II. Oc. D. ; 13d lh 51ra47s II. Ec. R., 10h 19"V
III. Tr. I., llh 10%; III. Sh. I.; 14d lh 36ram III. Tr. E.,
2h 27mw III. Sh. E., 8" 34% II. Tr. E., 9h 2% II. Sh. E. ;
15d3h 10mw I.Oc.D.; 16d0h17mm I. Tr. I., 0h33%» I.Sh. I..
2h 35%;; I. Tr. E., 2h 51%;; I. Sh. E., 9h 37% I. Oc. D. ;
17d Oh 8m 568m I. Ec. R., 9b 1% I. Tr. E., 9h 19% I. Sh. E. ;
20d Oh 58%;; II. Oc. D.; 21d lh 37%» III. Tr. I., 8h 47me II.
Sh. I., 9h 35rae IV. Tr. I., 10h49% II. Tr. E., llh 37% II. Sh.
E., 22d Oh 25ram IV. Tr. E., lh 22mm IV. Sh. I. ; 23d 2h 2mm
I. Tr. I., 2h 27%;; I. Sh. I., llh 21% I. Oc. D., 24d2h3m308m
I. Ec. R., 8h 28% I. Tr. I., 8h 35m 538e III. Ec. R., 8h 56% I.
Sh. I., 10h 46% I. Tr. E., llh 14% I. Sh. E. ; 25" 8h 32m 108e
I. Ec. R. ; 28d 10h 16% II. Tr. I., 1 lh 23% II. Sh. I. ; 29d lh 6%ra
II. Tr. E., 2" 13%w II. Sh. E. ; 30d 8h 23m 438e II. Ec. R. ;
31d lh 6mm I. Oc. D., 10h 13% I. Tr. I., 10h 51me I. Sh. I.
Near the time of opposition, the satellites, when crossing
the disc, are very close to their shadows.
Meteor Showers (from Mr. Denning's List) : —
Radiant
Date.
R.A.
1
Dec.
May 30 to Aug.
333
+
2°8
Swift, streaks.
,, to July .
252
—
21
Slow, trains.
June to Aug...
3'°
+
61
Swift, streaks.
,, to Sep. .
335
+
57
Swift.
„ to July ..
245
+
64
Swift.
,, to Aug....
303
+
24
Swift.
Julv 6-22
284
—
13
Very slow.
,» I5-3I —
23
+
43
Swift, streaks.
» '9
315
+
48
Swift, short.
„ 22-27 ...
335
+
5'
Swift, streaks.
July to Aug...
308
-
12
Slow, long.
July 25 to
Sept. 15
48
+
43
Swift, streaks.
July 28
339
—
1 1
Slow, long. The
uly Aqun-
rids, a conspicuous shower.
lulv to Sept...
335
+
73
Swift, short.
July 8-31
3"7
+
31
Swift, white.
July to Aug....
2S0
+
57
Slow, short.
July to Oct. . .
355
-t-
72
Swift, short.
The Perseids may be seen from July 19th, radiant 23° + 52c
advancing 1° per day in R.A.
Tab
le 45. Non-Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Maximum.
K Herculis
h. m.
16 2
+ l8°6
80 to 14
d.
3I7-7
June 23.
RR Herculis ...
16 2
+ 5° '7
7-8to 9-5
241
May 9.
U Serpentis ...
■ 6 3
+ IO '2
83 to 14
237-2
July 15-
SX Herculis ..
16 4
+ 25-1
7 '9 to 9'2
100-55
May 12.
W Coronae
16 13
+ 38 -o
7 • 8 to 12
244
July 14.
V Ophiuchi ..
16 22
— 12 '2
69 to 10 8
302-5
Apr. 20,
R Draconis
16 33
+ 66'9
64 to 13
245°
July 29.
Z Ophiuchi
17 15
+ i -6
T S to 13
348
May 10.
T Draconis
'7 55
+ 58 -2
75 to 12
426
Aug. 9.
RV Herculis ..
17 56
+ 19 '5
8-2 to 13
222-3
luly 22.
T Herculis
18 6
+ 31 -o
6-9 to 13
165
May 2, Oct. 13.
RV Ophiuchi
18 12
+ 3'6
8 ■ 2 to 13
1533
July 14.
W Lvrae
18 12
+ 36 '6
7-3 to 12
196-5
May 28.
RS Draconis .
18 40
+ 74 - 2
8 ■ 4 to 12
2SI
June 29.
SI) Sagittarii ...
■8 59
-22 -8
8-3 to 9
88
May 18.
R Aquilae
19 2
+ 8-i
6'2 to 11
337
May 15.
W Aquilae
19 11
- 7 -2
8'2 to 13
489
July 24.
R Sagittarii
19 12
-19 '5
7-oto 13
269
Aug. 16.
T Sagittae
19 18
+ 17 5
8-3 to 9-5
'56-7
June 14.
AK Cvgni
19 27
+ 46-0
7'0 to 80
94
May II, Aug. 13
TVCygni
19 30
+ 2S • 1
8-7 to 13
354
June 22.
RT Aquilae ...
19 34
+ n '5
7-6 to 12
325
Sept. 4.
RTCvgni
19 41
+ 48-5
6' 6 to 12
190-5
Mar. 22.
TU Cygni
19 44
+ 48 -8
8'5 to 14
225
July 21.
X Aquilae
'9 47
+ 4 '2
8'2 to 10
348
Aug. 18.
Saturn is badly placed, having been in conjunction with the
Sun on May 29th.
Uranus is in opposition on 29th. Semi-diameter, If".
Neptune is too near the Sun for observation, being in
conjunction on the 19th.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which two
hours will overlap with the following one. Thus the present
list includes R.A. 16h to 20h, next month 18hto 22h, and so on.
226
SOLAR DISTURBANCES DURING APRIL, 1913
BY FRANK C. DENNETT.
April has yielded very little by way of disturbance upon the
sun. His disc was observed every day, but spots were only
recorded on four — 5, 6, 7, and 22 — and faculae on ten
others— 1, 3, 8, 9, 12,16, 17. 20,23 and 24— whilst he appeared
free from disturbance on the remaining sixteen. The
longitude of the central meridian at noon on April 1st was
260° 37'.
No. 7. — First seen on the morning of the 5th, as two larger
and two or three smaller pores outlining the northern half of
an ellipse. These smaller pores changed somewhat during the
day, and the leader increased somewhat in size and became
divided. The spectroscope showed only very moderate
activity to the north-east of the leader, but dark hydrogen
flocculi were seen, and also the presence of the dark helium
line, D3. On the 6th it had increased somewhat, being 30,000
miles in length. The area between the spots and for some
distance northward looked disturbed, and this was confirmed
by the spectroscope, which also showed the presence of dark
hydrogen flocculi and dark helium. On the 7th only the
leader remained amid a faculic display, and died out before
the 8th, although the faculae remained visible until the 9th.
On the 22nd, at 3.30 p.m., there was a small but evanescent
black pore situated approximately in longitude 338°, latitude
28° S. where the cross is marked on the chart, but it soon
became gray, and disappeared.
A facula around 136°, 16° N. was seen on the 16th, when
larger paler faculic areas were situated at 351°, 16° N., and
351°, 28° N. The latter being seen also on the 17th. A
facula also seen on the 17th at 330°, 9° N. A small facula on
the 20th at 81°, on, or close to, the equator. On the 22nd and
23rd a faculic area was situated at 273°, 23° N. On the 24th
a pale faculic area, too faint for measurement, was round the
eastern limb apparently just south-west of the place of No. 7.
The chart is constructed from the combined observations
of Messrs. John McHarg, E. E. Peacock, A. A. Buss, and the
writer.
DAY OF APRIL, 1913.
so
19.
a
7
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15.
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13
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90 100 110 120 130 M » 160 M 180 190 30 2J0 220 230 M> S) M 270 2S0 31) 300 SO 320 330 Srf 3S0 560
REVIEWS.
ASTRONOMY.
The Solar System. — By G. F. Chambers. Second edition.
202 pages. 28 illustrations. 6J-in. X 4j-in.
(Hodder & Stoughton. Price 1/- net.)
This is a second edition, partly rewritten to bring it up to
date, of a work first published in 1895. The present edition
gives no year of publication — a frequent modern fault — but
from the date of the preface one can infer that the year was
1912 or later. The book is light and of a convenient size for
the pocket, also the paper and printing are both good in
quality. It has thirteen chapters, of which Chapters II (Sun)
and XIII (Comets) occupy seventy-five pages, or more than
one-third of the whole. The chapter on the Sun, pages 21 to
62, is almost entirely devoted to Sun-spots — in fact, all but
four pages, and, though very interesting reading, is out of
all proportion to the rest of the chapter and book. In the
next edition, which we hope to see during the author's life, we
should like to have quite twenty of these pages replaced with
something upon other parts of solar physics : for instance, a
general account of the beautiful phenomenon of the solar
corona, which can certainly be best viewed with a small, or
without any, telescope, cannot be adequately given in eleven
lines (eighty-one words), nor can the situation be saved by
giving an antique illustration.
The remarks upon scintillations in Chapter V are very
useful, interesting and suggestive ; the reference to Tacchini
on page 91 we can bear out from personal observations at an
altitude of two miles. Likewise the reference, on page 99,
to P. Smyth upon the exact similarity of terrestrial and lunar
volcanoes, we can substantiate from actual rambles among
the former and telescopic views of the latter. A brief reference
to the excellent results of lunar photography and Saunder's
work would not have been out of place. The remarks at the
top of page 107 do not appear to be courteously expressed.
We are glad to see the remarks on page 108 about the misuse
of a revered name.
Galle does not appear to have sufficient credit given him,
on pages 143 and 158, for his pioneer observations. On
page 146 we notice an error in the number of satellites for
Saturn. The chapters on Uranus and Neptune are concise
and full of facts. There is a useful index : we noticed the
omission of Aston and Titius, and the references under
Satellites might have been extended with advantage. Altogether
a book full of interest and facts, not fanciful, not overburdened
with numbers, but pleasantly written by that veteran pen and
published at such a cost that everyone should possess and
read Jt F. A. B.
Annuaire Astronomique et Meteorologique pour 1913. —
ParC. Flammarion. 49cannee. 404 pages. 135 illustrations.
7i-in.X4j-in.
(Paris: Librairie Ernst Flammarion. Price lfr. 50.)
A book full of useful astronomical and meteorological tables
and information, both for reference and for the amateur's
daily use. Pages 245-390 contain a resume of observations
and progress in 1912, and the last pages record facts upon the
scientific jubilee of Flammarion.
F. A. B,
227
228
KNOWLEDGE.
June, 1913.
BOTANY.
The Moorlands of North-Eastern Yorkshire. — By F.
Elgee. 356 pages. 3 maps. 71 figures. 8j-in. X 5i-in.
(A. Brown & Sons. Price 15/- net.)
As the author rightly claims in his preface to this work,
representing the results of his long-continued observations
on the geology and natural history of the eastern moorlands of
Yorkshire, we have here for the first time a comprehensive
book dealing with a British moorland area from a scientific
standpoint. The ecology of moors in various parts of Britain
has been dealt with in memoirs by members of the British
Vegetation Committee, while among Continental memoirs two
stand out prominently — Graebner's Heide Nord-Deutsch-
lands and Friih and Schrbter's Moore der Schweiz — but
the present work differs from all these in that it deals not only
with the plant life of the moorland but also the geology and
zoology in their relationship and interdependence.
The author does not claim to have produced a definite
monograph, and though every aspect of the moorlands has
been touched upon in his work, an exhaustive treatment of
each topic has not been attempted ; for instance, detailed
descriptions of moorland plants and animals have been
omitted, as these are found in works dealing with the British
flora and fauna. By judicious selection, and owing to his
having taken into account the current literature of the topics
dealt with, he has produced a striking contribution to ecology,
and since he indicates throughout the work the various
problems in moorland ecology which are still open to solution,
and upon which further search is required, the book is one
that should stimulate other workers in various districts to take
up some of the many questions raised. For instance, he
points out that the investigation of the peat deposits, layer by
layer, is a piece of research that is urgently needed, because
of the light it would throw upon climatic changes in post-
Glacial times and upon the development of the " mosses "
(moss-moors, Hochinoore).
The greater part of the book is of general rather than
merely local interest, since a large amount of space is given
to the consideration of subjects wnich have a general bearing
— the peat beds and the evidence they yield as to primitive
woodland on the moors, the relationship of the moorland flora
and fauna to the glaciation of the district, the origin of various
geological features such as outliers and inliers, the general con-
ditions determining the existence of moors, the origin of the
moorland flora and fauna, and the relations of the moorland
fauna to the flora. " The scope of the work," to quote from
the author's statement in the introductory chapter, " is to
exhibit the interdependence of all aspects of the moors : their
antiquities, plants, rocks, insects, stones, birds, and climate
form a coherent whole which cannot be fully understood
unless all are considered. We shall regard the moors as a
unique assemblage of factors of intense interest, which owe
their present status to innumerable causes that have been
operating for ages. In other words, we shall follow that
sequence of events which has led to the evolution of the
moorlands of North-Eastern Yorkshire." In this introduction
a general account is given of the general physical features and
the geology of the district.
In Chapter I the author discusses the antiquities of the
moorland, with some interesting notes on the etymology of the
terms " moor," " heath," and so on. On various grounds it is
concluded that from early times, perhaps three thousand
years ago, the high moors were never clothed with trees.
Chapter II deals with the "fat moors" — the typical heather
moor, or heath, with a well-developed peat-layer, often of
considerable thickness — as contrasted with the "thin moors"
considered in Chapter III, where the peat is thin and the
different associations are dominated by Calluna, Erica spp..
Scirpus caespitosus, Molinia and Nardus and other heath
grasses, Ulex, and so on. Chapter IV is concerned with
" mosses" — Sphagnum bog, cotton grass moor (" Eriophore-
tum vaginati"), and so on; Chapter V with the moorland
slopes, including associations dominated by bracken, birch
woods, oak-birch woods, larch and pine-woods, bilberry slope,
rush bogs with Sphagnum, and so on ; Chapter VI with the
interesting " slacks " and " gills " (small valleys with broad
flat streamless floors and steep slopes) which often present a
remarkable congestion of plant associations, so that many of
the types of moorland vegetation may be found within a
limited area. In connection with the "slacks" the author
gives an interesting summary of recent work on the plant
remains in peat deposits in Britain, and concludes that for
many thousands of years, probably even since the Ice Age
itself, the moors were islands and peninsulas of heath vegeta-
tion, surrounded by a great sea of forest and woodland, feelers
of which penetrated far into the heart of the uplands along
the sides of the streams. This subject is developed more
fully in Chapter VII, which is devoted to the geological effects
of the Ice Age on the moors, with an account of Professor
Kendall's investigations on the former glacier lakes of the
district.
The origin of the moorland flora is next discussed (Chapter
VIII), and the conclusion reached is that the geological
history and geographical distribution of the chief moorland
plants proves that the moors were formed in pre-Glacial times,
probably towards the close of the Pliocene period. This
leads to a further discussion in Chapter IX of the Ice Age and
the moorland flora, the history of the latter being summed up
in the following stages: (1) Evolution of Vaccinium spp.,
Eriophorum, Empetrum, and so on, in a northern land in
Pliocene times, and a gradual dispersal of these species south-
wards with the approach of the Ice Age ; (2) origin of Calluna
and Erica spp. in South-Western Europe and their dispersal
north and east during the Pliocene period ; (3) advent of the
Ice Age with survival of most of the northern species on the
driftless area — Erica cinerea, E. Tetralix, Myrica Gale,
and Pteris aquilina, however, probably driven from the
district ; (4) post-Glacial re-entrance of these four plants, and
development of moors from the Arctic plant communities of
the uplands and upon the bare ground ; (5) a warmer and
drier climate with a decline of wet moors and the growth of
trees in the slacks, gills, and dales and on slopes and parts of
the higher moors ; (6) an increased rainfall with an accelera-
tion of moor formation, and a destruction of the birch and
oak woods in the slacks and gills by the development of peat
bogs ; (7) the present moors, where peat formation and
destruction counterbalance each another.
Then follow four chapters of mainly geological interest,
and the work concludes with three extremely interesting and
suggestive chapters on animal life (in particular insect life) on
the moors, containing the results of the author's patient and
successful investigations in a field which has been com-
paratively little worked at, and a finely written general
conclusion, in which the author skilfully gathers up the
threads of the work and emphasises the importance of his
main theme — the interdependence of the various factors
which condition the moorland climate, physiography, flora,
and fauna. Extensive tables are appended, giving the chief
facts regarding the moorland lepidoptera divided into two
groups according to whether the food plants are Calluna and
Erica or Vaccinium. This portion of the book forms a
mine of information concerning the insect fauna of moor-
lands and its relation to the flora.
There are two large maps coloured to show the geological
formations and the distribution of moorland respectively in
north-east Yorkshire,' and a map of typical geological sections.
Of the photographic plates with which the book is lavishly
illustrated all are excellent and many are particularly fine.
This book will certainly rank as a standard work on British
vegetation, and it is to be hoped that the successful publica-
tion of a work of this scope will be followed by the production
of other books dealing in a similar manner with the vegetation
of larger or smaller areas of the British Isles.
By the courtesy of the publishers we reproduce here two
of the plates illustrating Mr. Elgee's work (see Figures
235 and 236).
F. C.
From a photograph FIGURE 235.
Birch Wood and Juncus Swamp, Eston Hills, Yorkshire.
by Frank Elgcc.
From a photograph FIGURE 236.
Loose Howe, Rosedale Head, Yorkshire.
From " The Moorlands of North Eastern Yorkshire."
229
by Frank Elget.
230
KNOWLEDGE.
June, 1913.
Economic Woods of the United States. — By Samuel J.
Record, M. A., M.F. 117 pages. 6 plates. 9^-in. X6-in.
(Chapman & Hall. Price 5/6 net.)
This book is most complete for a somewhat condensed work
on the subject, and is offered at a very reasonable price. It
refers to U.S.A. timber trees onlv, but a large number of these
are important to us owing to their commercial uses and also
in several cases to their value for planting in this country.
The book is well arranged; each point is dealt with in a
businesslike and concise manner, and with as little repetition
as possible. The language is clear, and it is refreshing to
find no peculiar American phraseology or spelling.
Part I deals with the structural and physical properties of
wood, and contains much of interest to the student in technology,
the forester and the commercial user of timber. Although
many of the points arc of necessity dealt with in a somewhat
condensed form the ground is well covered, and after each
heading is given a list of textbooks referred to and from
which more detailed information can be procured where
desired. A complete list of references, including the standard
books of each branch, is published at the end.
Part II is a key with photomicrographs of some of the
American timbers, and is useful for showing the main character-
istics in structure ; but it is somewhat limited in its application.
The work, although not intended to be original, brings
together a mass of useful information, and, taken altogether,
is a welcome and valuable addition to the literature on the
subject. It should appeal to those who require a general
grasp and have neither the time nor the means to go deeply
into every point.
M. C. D.
GEOLOGY.
The Petrology <>f tlic Sedimentary Rocks. — By F. H.
Hatch and K. H. Rastai.i . 425 pages. 60 figures.
7i-in.X 5-in.
(G. Allen & Co. Price 7/6 net.)
The petrology of the sedimentary rocks has been much
cultivated lately, and although it was neglected in the early
days of the science compared with the igneous and meta-
morphic branches, it is now coming into its own. This book
represents a culmination of interest in which sedimentary
petrology threatens to rival the other branches in its
attraction for workers. The literature of the subject is large
and scattered, and the authors are to be congratulated on
their successful attempt at its collation in the book under
review, which is the first of its kind. The title scarcely
records the scope of the work, since the majority of rocks
usually treated as metamorphic are also described. The term
'" iiietamorphisin " is used in its widest sense to indicate all sorts
of change in rocks, cementation, metasomatism, and
weathering, as well as the severer forms due to great heat and
pressure which result in the production of rocks included as
metamorphic in the narrower sense. There are certainly no
sharp boundaries between the various types of change, and
logically, therefore, the plan of the book is unassailable. We
think, however, that the inclusion of the metamorphic rocks
might have been more prominently indicated in the title; or
alternatively they might have been relegated to another
volume. i he use of the term " metamorphic " in such a wide
sense involves the incongruity that our typical sedimentary
rocks, such as sandstone, shale, and limestone, are treated in
the second part of the book under the heading " Metamorphic
Derivatives of the Sediments," and the cursory student may
be somewhat at a loss on finding their descriptions in this
place. It is to be admitted, however, that, given the definition
of inetainorphism here adopted, the arrangement of the book
is perfectly logical.
In the first part of the book the modern sediments are
dealt with under the headings of " Deposition in General,"
" Fragments! Deposits," "Chemical Deposits," and "Organic
Deposits." In Part II the older sediments which have under-
gone various types of change are described under the headings
" Metamorphism in General," " Cementation and Metasoma-
tism," '* Contact Metamorphism," " Regional Metamorphism,"
and " Weathering." In these chapters very lucid accounts of
the methods of deposition and the modes of change in the
sediments are given. In fact the book is really a well-knit
and concise account of the pedogenesis of the sedimentary
rocks. Because of this fact, and perhaps also because of its
limited size, the book is a liltlc disappointing on the
petrographical or descriptive side. Its plan also involves
some discontinuity of treatment for sediments which are
related in various ways. The calcareous rocks, for instance,
excluding the metamorphic types, are to be found under three
headings. The ordinary sedimentary limestones in general
appear to be inadequately described as compared with the
sandstones and shales. Referring to the index we find five
entries under " limestone," but four of these refer to
metamorphic types and the other to cave-limestone. In other
parts of the index we find additional references to crinoidal
limestone, dune-limestone, and dolomite, but none to oolitic
limestone. Then no description of the ways in which the
various organisms which build limestones may be recognised
is given.
These, however, are but small spots on the sun of the
general excellence of the book, and inasmuch as the authors
have in our opinion accomplished what they set out to do, and
have produced a most interesting and important work, they
are entitled to all praise. They have been fortunate enough
to secure a most useful appendix, by Mr. T. Crook, on "The
Systematic Examination of Loose Detrital Sediments," in
which are described the methods of separating and identifying
minerals in small fragments. „ ... ~
Li. W. 1 .
.-1 Manual of Petrology. — By F. P. Mennell. 256 pages.
124 figures. 9-in.X5J-in.
(Chapman & Hall. Price 7/6 net)
This book is based on the author's " Introduction to
Petrology," the second edition of which was reviewed in
" Knowledge " of August, 1910. It differs from the earlier
book in several particulars. The chapters on the origin of
igneous rocks and on metamorphism have been re-
modelled, and the position of some chapters has been
altered. Many of the illustrations are new, and, as a
whole, are decidedly better than in the former work.
We wish we could say the same of the classification of
igneous rocks adopted. Mr. Mennell "simplifies" peno-
logical nomenclature by classifying igneous rocks into five
groups according to silica percentage, and each of the latter
into three divisions of plutonic, intrusive, and effusive types
respectively. By this method he gets fifteen classes, for
which fourteen names are supplied, the ultrabasic plutonic
rocks {i.e., those with less than forty-five per cent, of silica)
not being provided with a name. Varieties are indicated by
mineralogical prefixes. It is a delusive simplification, however,
which reduces the nomenclature of a science, for progress or
increasing complexity demands an increasing nomenclature.
In particular the silica percentage is an extremely artificial
attribute on which to base a classification Thus, for example,
to call all plutonic rocks with a silica percentage between fifty-
five and sixty " diorites," and thus to include the majority of
nepheline-syenites, is merely to introduce confusion, just as it
would introduce confusion to call all marine animals " whales,"
or all land animals " elephants," on the strength of a community
of habitat.
The classification by silica percentage ignores the fact that
rocks are composed not of silica percentages, or of per-
centages of various oxides, but of minerals. Hence the
mineralogical variations in rocks are the most significant
variations, and should be those expressed in the major
divisions of the classification. Not less, but more, nomen-
clature is needed for the philosophical discussion of petrological
principles. What is needed is not a reckless aggregation of,
for example, such unlike units as nepheline-syenite and diorite
into one group, but a more subtle and closer characterisation
of igneous types leading to a more detailed classification.
In this book the classification by silica percentage leads to
|UNE, 1913.
KNOWLEDGE.
231
such anomalies as the inclusion of ditroite in the diorite group
(page 144) ; the treatment of kentallenite and borolanite
under that very accommodating term " dolerite " (page 156) ;
and the use of such a term as " nepheline andesite," which is
almost a contradiction in terms if the ordinary definition of
andesite is to stand. If there is one rock that can be said
never to contain nepheline that rock is andesite ; and it does
not mend matters when we find that by " nepheline andesite "
the author means ' phonolite." Hence, so far as the classifica-
tion of igneous rocks is concerned, this book cannot be
recommended to the student, who, since he has to identify
his rocks by their
mineralogical content,
and is rarely able to
determine their silica
percentage, would be led
into hopeless confusion.
The chapter on the
origin and variations of
the igneous rocks is
interesting and provoca-
tive of thought, although
very speculative. The
sedimentary and meta-
morphic rocks are also
treated in a thoughtful
and useful manner.
Indeed the rest of the
book is so good that it is
a pity the author does
not see fit to bring his
views on the classifica-
tion of igneous rocks
more into accordance
with the experience of
the great majority of
petrologists.
G. W. T.
MICROSCOPY.
The Beginner's Guide
to the Microscope. — By
Chas. E. Heath. 119
pages. 46 illustrations.
7-in. X 5-in.
(Percival Marshall. Price
1/- net.)
The microscope is now
used in connection with
so many different matters
and the advantages of
the training which it gives
to hand, eye, and brain
are so widely recognised that a book such as the present one,
which tells in simple language what the microscope is, and
how it can be used, is worthy of the most cordial welcome.
We think that in this beginner's guide the author has just
happily chosen those points of the greatest value and
he has not gone into such detail as to bore those for
whom he writes. His advice, too, is sound ; as, for instance,
when he urges the beginner who wishes to get a good
microscope to buy no instrument nor objective that does not
bear the name of a recognised maker,
By the courtesy o/
Figure 237
Wapiti-red- Deer Cross, bred at Surrenden Park, showing red deer
type of head, from " Deer Breeding for Fine Heads.
W. M. W.
PHILOSOPHY.
The History of Magic, including a clear and precise
Exposition of its Procedure, its Rites and its Mysteries.
— By Eliphas Levi (Ai.phonse Louis Constant).
Translated, with a Preface and Notes, by Arthur Edward
Waite. 536 pages. 20 plates. 8|-in. X5Mn.
(William Rider & Son. Price, cloth, 15/- net;
vellum, 21/- net.)
A great poet:': has said: " Everything possible to be believed
is an image of truth." Certainly the belief in the efficacy of
magical practices would not have persisted for so long had
not these practices been productive of results. No doubt the
phenomena thus produced must be classed as " subjective,"
and the question of Magic is one for psychology rather than
physics. The literature dealing with the history of Magic
from this point of view is, however, very slight : until the
publication of this translation (by which all students are laid
under a debt of gratitude to Mr. Waite) there was nothing of
much importance in the English language other than Mr.
Howitt's translation of
Joseph Ennemoser's
work.
One requires to know
something of Alphonse
Louis Constant to apprec-
iate his works aright.
He was lacking in the
precision and accuracy of
the scientific man ; his
reading, though wide, was
careless, and he rarely, if
ever, verified his quota-
tions ; he was apt to see
his own theories every-
where, and it was seldom
that he could resist the
desire to elaborate tra-
dition and legend. But,
in spite of their many
defects, his books exhibit
a brilliancy of imagina-
tion and a charm of
expression which render
them of real value.
Indeed, Constant was by
no means lacking in
philosophical insight, and
was certainly well versed
in his subject.
Magic, in Constant's
terminology, was origin-
ally the absolute science
of equilibrium. It
degenerated, however,
until it became, as it
were, a disease of the
imagination. Indeed,
during the period of the
witchcraft persecutions
it became almost an
epidemic, and the evil was
accentuated by the fact
that it was supposed that an exorcised, " devil " could not
speak untruthfully, so that innocent persons were accused
and convicted of the most horrible and impossible crimes on
the evidence of persons suffering from nervous and mental
disease. Nevertheless, according to the author, the doctrines
of Magic embody profound philosophical truths, though in a
distorted form. I am inclined to agree with this view; though
I doubt whether Constant's assumption of a universal medium
(which he fantastically calls "the astral light"), upon which
the imagination can act either for good or evil, will appeal to
modern psychologists.
Constant owed much to the Kabalah, i.e., the books which
claim to contain the secret philosophical traditions of Judaism.
It is interesting to note that the cosmology of the Kabalah is
definitely heliocentric, and I am inclined to think the books
are worthy of more study than is devoted to them. From this
source Constant derived his central doctrine of equilibrium,
though he interpreted it in his own sense and applied it to
every department of thought.
Mr. Waite's careful and scholarly notes, in which he
corrects some of Constant's misstatements and throws
Rowland ll'a
William Blake.
232
KNOWLEDGE.
June, 1913.
further light on the obscure subject of Magic, add very
greatly to the scientific value of the book.
H. S. Redgrove.
PHYSICS.
Introductory Electricity and Magnetism. — By Carl W.
Hansel. 373 pages. 283 illustrations. 7i-in-X5-in.
(William Heinemann. Price 2/6 net.)
This book is obviously the work of an experienced
teacher, and deserves the careful consideration of all con-
cerned in preparing for
elementary examinations n
in this subject. The 4 //
figures are excellent, and
there is a refreshing
absence of confused pho-
tographic reproductions.
At the end of each sec-
tion questions for revision
are given.
W. D. E.
Elementary Experi-
mental Dynamics for
Schools. — ■ By C. E.
Ashi-oru, M.A. 246
pages. 94 illustrations.
7J-in.X5-in.
(The Cambridge Univer-
sity Press. Price 4/- net.)
This useful little book
scarcely needs the
apology which the author
makes for it in his
preface. The principle
of approaching the study
of Kinetics by an induc-
tive method is now fairly
well established, and the
arguments for it are
recapitulated here. In
the text itself the
measurement of velocity
and of small intervals of
time is approached by
way of Fletcher's trolley
and vibrating paint-
brush, and the notion of
variable velocity is intro-
duced by distance-time
diagrams plotted from
Bradshaw on squared
paper. The notions of force and of the relation between gravi-
tational and kinetic units of force are led up to by further experi-
mental work with the trolley and paint-brush. An experimental
verification of the formula for kinetic energy is new to us. The
chapter on Fluid Pressure is a link between the past and the
present of our Navy, as it deals with wind pressure on sails and
also with the Parsons steam turbine. Teachers of mechanics
will find many hints in this book, even if they cannot afford to
invest in all the apparatus which the British taxpayer supplies
to our naval colleges. W. D. E.
YEAR BOOK.
Directory of Museums in Great Britain and Ireland;
together with a Section on Indian and Colonial Museums.
— By E. Howarth, F.R.A.S., F.2.S., and H. M. Platnauer,
B.Sc. 312 pages. 8i-in. X5^-in.
(The Museums Association. Price 10/-.)
We have received a copy of the Directory of Museums,
which gives briefly but in a very useful way much valuable
information with regard to the National and Local Institutions
of this country, as well as the more important Indian and
Colonial Museums. We learn who is responsible for the
various Museums, how they came into existence, what they
specially intend to illustrate, as well as what work of an
educational kind is carried out by the staff. The book should
be in every reference library. W. M. W.
ZOOLOGY.
Life and Evolution. — By F. W. Headley. 272 pages.
98 illustrations. 8j-in.X6-in.
(Duckworth & Co. Price 5/- net.)
Based on lectures delivered to the natural history class at
Haileybury College, this attractive volume was first presented
to the public in 1906, and its reappearance in the form of a
new and revised edition affords such testimony of its popularity
that commendation on our part seems superfluous.
Among the chapters
that have undergone
special revision are those
on flight, but when dis-
cussing (page 98) the
manner in which the
giant pterodactyles of
the secondary epoch
were enabled to sustain
themselves in the air, the
author appears to have
overlooked an important
paper published last year
in the Bulletin of the
Geological Society of
France, in which Messrs.
E. and A. Harle maintain
that without an atmos-
pheric pressure much
greater than at present
exists flight in the case
of these monstrous rep-
tiles would have been an
absolute impossibility.
He might also (page 141)
have referred to Sir
Hiram Maxim by his
proper title instead of
as Mr. Maxim.
Some of the sentences
in various parts of the
work would also have
been the better for re-
vision, as is exemplified
by the unnecessary repe-
tition in the following
statement (page 89) : —
" The reptile that seems
to carry off the prize for
speed is an Australian
\izaid,Chlamydosaurus
kingi. Chi amy do-
saurus is an Australian lizard, being found in Queensland."
Apart from slight shortcomings of this nature, the book is
an excellent epitome of modern views on evolution. R. L.
Deer Breeding for Fine Heads, with Descriptions of many
Varieties and Cross Breeds.— By Walter Winans, F.Z.S.
105 pages. 34 illustrations. ll-in.X9-in.
(Rowland Ward. Price 12/6 net.)
The first object of Mr. Winans' book is to show that the
Deer should be looked after and bred as carefully as any
other animal which is kept in captivity. His illustrations
show how well he has himself succeeded. Incidentally, how-
ever, in the book an account is given of cross-bred deer, and
by the courtesy of the author we are able to show pictures of
the heads of the cross between the Wapiti and red deer as
well as between the Altai and red deer. Mr. Winans has
gone further and crossed a Wapiti-red- Deer hind with an
Altai stag, so that he has now Wapiti-Altai-red-Deer hybrids,
a cross which he believes has never before been attempted.
There is much of great interest and usefulness in the book,
and we may allude to the chapters on the preservation of
Horns ; on the precautions to be taken to avoid injury by Deer,
and with regard to the times of breeding. Artists should read
the notes on the action of Deer and take to heart what Mr.
Winans has to say about the drawing of animals. W. M. W.
V the courtesy o/ Mr. Ktnclaiid Ward.
FlGU
Cross-bred Altai-red-Deer, from " Deer Breeding for Fine Heads.
COMETS
By F. W. HENKEL, B.A., F.R.A.S.
These still mysterious bodies have always been of
the highest interest both to the astronomer and the
" man in the street," and though the progress of
science has robbed them of much of the terror their
occur from day to day, and the extraordi nan-
behaviour of parts of their substance when nearest
the sun, seem to indicate the existence of matter in
a physical condition unlike anything of which we
have experience here, and from the want of such
information our knowledge of cometary physics is
necessarily defective. Thus, to the wonder and
terror formerly inspired by a comet has succeeded
the scientific wonder and curiosity at beholding the
behaviour of "matter" under almost unimaginable
conditions.
In earl)1 days, no doubt from the rarity and
unexpectedness of their appearance and the remark-
able nature of the appendages which many of them
possess, comets were regarded with fear and trembling
not only by the general public but also by the
learned, and in fact, much of the terror of the former
was due to the credence they gave to the baseless
conjectures of the latter. This feeling has by no
means died out, to judge from what one hears and
reads with regard to recent comets, but its nature
has perhaps slightly changed. Formerly such " wars,
pestilences and the death of princes " as occurred
shortly after the apparition of a comet were
attributed on the sufficient principle of post hoc, ergo
propter hoc, combined with the idea that all things
had direct effect upon human destinies (the
Figure 239. Comet 1908 III (Morehouse).
P. J. Melotte and C. R. Davidson, Royal Observatory,
Greenwich. 1908, Sept. T 14h 56m G.M.T. Position of
Comet: R.A. 3h 3m ; Decl. + 69° 38'. Reflector: Ap. 30-in.
(0-762m); F.L. 1 1 -ft. 5-in. (3 -48m). Exp. 60 mins.
unexpected apparitions formerly inspired, whilst
the calculations and verifications by returns, as
well as discoveries of the last generation, have to
some extent satisfied our curiosity as regards some
of the phenomena presented by them, yet other
problems have arisen demanding solution for which
the data we at present possess are inadequate.
The regular return of certain well-known comets,
such as Halley's and Encke's, though on the one
hand affording ample demonstration of the justice of
the principles and methods employed by astronomers
for the determination of their orbits, yet on the
other hand, even for these comets, unexplained,
though small deviations from their calculated paths
afford material for speculation as to the nature of
other agencies besides gravitation affecting their
motion. Other comets there are, however, which
have failed altogether to return, notwithstanding the
great increase of accuracy in our knowledge of their
orbits, whilst for those that do return, as well as for
new comets, the remarkable changes of form that
s "*S v \ o^ \* \\ ; . V v*\ ^ v <
N A\ \ ^ ^
N .
; \v\ v'^ A v
' ^ \
| ^
x ^ ". /s
Nx\ \
\ \ s •
k
X ^
X\X Xs ^ ">
\ X _ . X
v\ X x s
FIGURE 240. Comet 1908 III (Morehouse).
E. E. Barnard, Yerkes Observatory. 1908, Oct. ld 19h 15™
G.M.T. Position of Comet: R.A. 21h; Decl. + 71°. Bruce
Doublet Lens: Ap. 6-in. (0-153m); F.L. 50-3-in. (l-28m).
Exp. 65 min.
233
234
KNOWLEDGE.
June, 1913.
Geocentric concept of the universe), to their baleful
influence ; in later days for the same good reasons
the weather conditions of our own earth were
supposed to be modified by their presence, and
examples of this are to be found in most
astronomical works, as well as in our paper
"Comets and the Weather" contributed to Symons's
Magazine. Donati's comet of 1858 was thus made
answerable for the hot weather prevailing that year
in England, Biela's comet in 1832 similarly in-
fluenced the summer of the "year of reform," whilst
the great comet of 1811 caused the ripening of the
grapes in some provinces of France, resulting in one
of the most wonderful vintages ever known. The
same comet of 1811, appearing shortly before
Napoleon's disastrous
campaign in Russia, is
credited with having un-
favourable omens drawn
from it by the Russians,
but here it would appear
that the omens were
worse for the invading
French army than for
themselves. If the
comet of 1769, which
appeared at the time of
his birth, is to be re-
garded as Napoleon's
presiding and protecting
genius, this one must be
considered as his evil
one. The origin of all
such notions, as has been
well remarked, is to be
looked for in the vanity
of man and his self-
constituted rulers, per-
haps more excusable in
the days when our
little earth was looked
upon as the centre of
the Universe than in
our own, but none the
less utterly without foundation. The natural
desire of the human mind to resolve mysteries was
satisfied by the pretended explanations of those who
knew no more than their questioners, whilst the bold
confession that we are all ignorant and merely as
children picking up a few pebbles on the shore
whilst the great ocean of truth lies unexplored
(Newton) was reserved for later days. Though
the encomium of Pope upon Newton
" Nature and Nature's laws lay hid in night,
God said, let Newton be, and all was light,"
is, of course, in excess of the truth and as we have
seen, Newton himself did not think so, yet there
probably has never: been any work of human genius
greater than the incomparable " Principia." Here, for
the first time, it was definitely laid down that a body
moving under the influence of a central force (such
as gravitation) varying inversely as the square of
its distance from the centre of force, will describe
one of the conic sections, an ellipse (circle as a
special case), parabola or hyperbola. It had been
previously suspected that one or two comets moved
in long ellipses or parabolas and Dorfel in 1680
showed that the great comet of that year moved in
such a path. Newton showed that its motions
were entirely in accordance with gravitational
principles and the parabolic elements of its orbit
were calculated according to methods given by him.
This comet approached unusually close to the Sun
when nearest, and for a short time must have " been
heated to a temperature many times that of molten
iron" (Newton). Hallev considered that this comet
moved not in a para-
bola but in a very long
ellipse, giving it a period
of five hundred and
seventy-five years, which
led Whiston in his " New
History of the Earth"
to speculate that it was
to an earlier return of
this comet that the
debit:
had
Figure
Comet
P. J. Melotte and C. R. Davidson, Royal Observatory,
Greenwich. 1908, Oct. 3d 9h 4m G.M.T. Position of Comet :
R.A. 20h 44m; Decl. + 68° 58'. Reflector: Ap. 30-in.
(0-762tn) ; F.L. 11-ft. 5-in. (3-48m). Exp. 30 min.
Noachian
been due, and that at a
later return it would
cause the destruction
of our planet by fire !
However, Encke's later
calculations, ascribing a
period of eight thousand
eight hundred years to
the comet, are to be
preferred to Halley's
result, so that Whiston's
speculations need not
be further considered.
The three curves
known as the conic sec-
tions ; parabola, ellipse
and hyperbola, as their
names imply, may all
be obtained by cutting a cone in different ways
by a plane, but perhaps they may be more
intelligibly defined to the non-mathematical as
being obtainable by throwing the shadow of a
circular disc upon a plane surface, such as a table.
If the disc be held parallel to the table, we get a
circle, if obliquely an ellipse, a closed oval curve; if
we hold it edgeways to the light we have a straight
line. If now we raise the disc so that its highest
point is on a level with the source of light, we shall
get a parabola, which is oval at one end, but the two
sides open out and do not meet again. If now we
hold the disc still higher, we shall get another curve,
whose two sides will separate even further from the
other. This curve is the hyperbola (or geometrically
one branch of the hyperbola, there being another
similar branch).
Whilst the planets move in ellipses little differing
June, 1913.
KNOWLEDGE.
235
from circles in most cases, the comets in general are
found to move in orbits so nearly parabolic (whilst
in the small part of their path during which they are
visible to us), that only a few are known whose
motion is otherwise, all three curves differing but
little near the vertex. Thus the orbit of a newly-
discovered comet is always first calculated on the
assumption that its motion is parabolic ; another
reason being that the necessary calculations are
simpler than for an elliptic or hyperbolic orbit. A
strictly parabolic orbit, however, is practically impos-
sible, for the smallest diminution of speed due to
planetary action would change it into an ellipse,
The vast majority appear to move approximately
in parabolas, a considerable (and increasing) number
in ellipses whose deviation from circularity is much
greater than that of the planetary orbits, but not
always so great as that of some double-star orbits.
In 1682, a comet was observed by Newton, Halley
and others, and on examining the circumstances of
its motion Edmund Halley computed its orbit on the
supposition that the latter was a parabola. Com-
paring his results with former observations and
computing other orbits from the necessarily
imperfect determinations of position of earlier days,
he found that in 1531 and 1607, comets had
Figure 242. Comet 1908 III (Morehouse).
E. E. Barnard, Yerkes Observatory. 1908, Oct. 15d 12* 57m G.M.T. Position of Comet: R.A. 19h 27'" ;
Decl. + 50° 16'. Bruce Doublet Lens: Ap. 10-in. (0-254m) ; F.L. 50-3-in. (l-28m). Exp. 82 min.
whilst an increase would convert it into a hyperbola.
The remarkable fact that so many cometary orbits
closely approximate to a parabolic form must have
important bearings on any theory as to their origin,
though there are reasons for suspecting that the true
orbits are not really parabolic, but very long and
eccentric ellipses. A comet moving in a parabola (or
hyperbola) will be seen only once, never to return ;
whereas, one moving in an ellipse, the latter being a
closed path, must return again sooner or later,
though thousands, or even perhaps millions, of years
may be required to complete one revolution round
the sun, their centre of force ; the common focus of
their orbits. A very few comets have been suspected
to move in hyperbolic orbits, but the deviation in
excess of parabolic velocitv is always so small, that
it may reasonably be doubted whether any known
hyperbolic-moving comet has been certainly detected.
appeared which moved so nearly in the same path as
this one that he ventured to assert its identity with
them, and to predict its return in 1758 or 1759.
Though he could not expect to witness this event
himself he wrote on the subject : " If it should
return according to our prediction about the year
1758, impartial posterity will not refuse to acknow-
ledge that this was first discoveredby an Englishman."
It is well known that his prediction was completely
verified, and the comet's latest return (after 1758
and 1835) is so recent that the details must be
familiar to all readers of " Knowledge." The
true glory of a nation, not obtained at the expense
of any other, nor involving the sacrifice of precious
lives, is shown more by such achievements than by
deeds of homicidal conquest, and we may be justly
proud of the names of our countrymen Newton,
Halley, Herschel, Cowell, Crommelin, and so on,
236
KNOWLEDGE.
June, 1913.
in connection with the history of this comet, whilst
not detracting from the honour due to Clairaut,
Pontecoulant, Max Wolf and other " foreigners "
who have assisted in the same field. At its last
return the brilliant development of the tail
phenomena, and so on, made the comet an object of
great beauty and interest to observers in more
favoured latitudes than our own (where the prevalence
of moonlight and the short summer nights prevented
or hindered observation) showing that the idea that
the comet, through the loss of matter driven off at
former returns, would be less conspicuous than of old,
was groundless. In fact, it is safe to assert that at
no previous return known to history has the comet
been so brilliant, whilst its early discovery by photo-
graphy and long visi-
bility have enabled its
changes from day to day
to be registered with a
completeness hitherto
unapproached. In addi-
tion to the physical
phenomena of interest
developed, it is of in-
terest to note that there
remains an outstanding
difference between
theory and observation,
whereby the comet's re-
turn to perihelion occur-
red three days later than
the date indicated by
the final previous cal-
culations of Drs. Cowell
and Crommelin, which
difference is not due to
the action of any known
material in the Solar sys-
tem. This may, per-
haps, be accounted for
as the result of the action
of an unknown planet,
but the present writer
has suggested that this
may be an effect of the resisting medium. Halley's
comet moves in the retrograde direction (that is to
say "clockwise" or opposite to that in which the
planets and many of the known periodic comets
move), and as there is some evidence that
Encke's comet (a direct moving comet to be referred
to directly), is slightly accelerated by such an action
it may not be unreasonable to suppose that the
opposite effect may be experienced by a retrograde
one. The comets are bodies of such infinitesimal
mass, combined with great volume, that their density
must be inappreciably small, so that an action quite
unobservable for the more massive planets may well
be sensible for them. The most remarkable of the
regularly returning comets is that of Encke. Its
periodicity was first detected by the astronomer of
that name, from the comparison of the orbits of
comets which appeared in 1786, 1795 and 1805, with
that which was discovered by Pons in November,
1818, and from his researches on its motion, con-
tinued up to the time of his death, the comet has
ever since been known by the name of Encke's
comet. It has the shortest period of any known
comet, rather over one thousand two hundred days.
But it was not long after it had been observed at
some following returns (1825, 1829 and 1835) that
Encke found a slow progressive diminution of its
period, and was led to conjecture the existence of a
" thin ethereal medium," which, continually resisting
the comet's motion, drew it slightly nearer towards
the Sun than would otherwise be the case, this
diminution of distance (by Kepler's third law)
involving a diminution of period. This diminution
continued at the follow-
ing returns, after the
death of Encke. His
comet has been carefully
studied by Von Asten,
and more recently by
Dr. Backlund, for whose
researches the gold
medal of the Royal
Astronomical Society
was given in 1909. He
finds that the diminution
in period has not been
quite regular, but has
undergone changes, fall-
ing, after 1858, to three-
fourths its former value
between 1861 and
two - thirds only
1871 to 1895, and
1895 having had
half the value it
1868,
from
since
onlv
had
then,
Figure 243. Comet 1908 III (Morehouse).
P. J. Melotte and C. R. Davidson, Royal Observatory,
Greenwich. 1908, Oct. 30d 7h 47m G.M.T. Position of
Comet: R.A. 18h 59m ; Decl. + 25° 18'. Reflector: Ap.30-in.
(0-762m) ; F.L. 11-ft. 5-in. (3-48m). Exp. 10 min.
before 1860. If,
we attribute this " ac-
celeration" to the action
of a resisting medium,
which tends to bring it
nearer the sun, we
obtain the somewhat
paradoxical result that the nearer the comet ap-
proaches the sun the less is its motion affected.
But the seeming contradiction may be explained if,
as the late M. Eaye suggested, the medium has some
motion of its own. " A comet moving in a resisting
medium of this kind will not be precipitated upon
the Sun, but the principal effect will be a change
(diminution) in the eccentricity of its orbit. This
will become more and more nearly circular, but after
a time the axis will no longer decrease." In fact, a
stationary resisting medium is incomprehensible,
unless it be infinite in extent, for otherwise it would
have been long since precipitated upon the surfaces
of the sun and planets. Professor See has shown
the action of a resisting medium in past ages in
effecting the approximate circularity of the planetary
orbits, and here we seem to have indications of the
present action also of such as still remains
June, 1913.
KNOWLEDGE.
237
unabsorbed by the larger bodies of our system. As
our knowledge of cometary orbits becomes more
exact, it seems reasonable to suppose that other
comets will be seen to be similarly affected.
Faye's comet of 1843, Winnecke's comet (1858 ii)
with a period of six years, and one or two others
(Tempel Swift's and Brorsen's comets) have also
been suspected to show
some evidence in their
motion of such action,
but the evidence is
somewhat conflicting,
since the difficulties in
the way of determining
the "undisturbed orbits"
of comets with sufficient
accuracy to prove so
small a "residual effect "
are many. A comet
cannot have its place
fixed with the precision
that is possible for a
planet. The perturba-
tions due to planetary
action are very import-
ant, and few comets
have been observed at
' more than five or six
returns over very
limited portions of their
orbits. Halley's and
Encke's comets alone
have been observed at
many returns, and it
happens just for these
that we do seem to
have some evidence of
the action of a re-
sisting medium, ac-
celerating the direct
moving comet and
retarding the retrograde
one. In addition to
Faye's explanation of
the varying effect of
resistance, Dr. Backlund
isinclined to think
that (neglecting possible
electrical actions) there may be a resisting medium
forming a sort of meteoric ring, whose density
diminishes as we approach the Sun within certain
limits, and that the diminution of resisting effect
may be a measure of this. Sir John Herschel
suggested that since the phenomena of comets' tails
show that matter is violently repelled from the
comet by solar action, the loss of such matter at
each return will render its proportion to the attracted
material less, and thus the " effective mass" will
increase, and, consequently, the comet will complete
each revolution in a shorter time. But it seems
difficult to imagine how such a change can produce
an effect of several hours' diminution in the period of
P- J-
Greenwich
Comet
(0
1908,
Nov. 19d 6h
Encke's comet, and, of course, it cannot explain the
retardation of Halley's comet.
Amongst the most remarkable of recent comets
we may easily give the foremost place to that
discovered by Morehouse on September 1st,
1908, which was continuously and extensively
observed. (See Figures 239-245). It underwent
many remarkable
changes during that
time, and considerable
discrepancies occurred
in the accounts of its
peculiarities. At its
first detection, and for
some weeks later, it
was a somewhat diffuse
cloud}' - looking object,
with barely a trace of
nucleus and a short
tail, which was even
visible to the naked
eye at Copenhagen on
September 20th. To-
wards the end of the
month, however, changes
took place resulting in
a complete disruption,
and on the 30th the
tail was entirely gone.
Photographs taken on
October 2nd show new
faint tails, whilst on
October 14th a tail at
least 7° long was shown.
The following day the
comet had broken in
two. Photographs
taken in the United
States show two great
condensations in the
tail, about J° from the
head : a bright, short,
spike - like projection,
with one end between
the two masses and
the broad end attached
to the comet, formed
the new tail (Chambers).
Further changes took place from day to day. End-
less streamers shot out from the main body of the
tail, which was violently bent and twisted as though
it had encountered a resisting medium (Novem-
ber 15th). On November 19th, straight jets were
given off by the head. The comet repeatedly lost
its tail and formed new ones, which varied in type,
" condensations, waves, straight rays, and twisted
funnels made up its wonderfully active tail."
The spectroscopic observations of this comet were
not less remarkable than the visual ones, and have
led to a great increase in our knowledge of cometary
physics. Admirable photographs were taken by the
Comte de la Baume Pluvinel and M. Baldet, with
Figurk 244. Comet 1908, III (Morehouse).
Melotte and C. R. Davidson, Royal Observatory
4m G.M.T. Position of
R.A. 18" 51m; Decl. + 2° 20'. Reflector: Ap. 30-in.
762m) ; F.L. lift. 5-in. (3-48m). Exp. 30 min.
238
KNOWLEDGE.
June, 1913.
the prismatic camera ; by Messrs. Frost and Park-
hurst, at Yerkes ; by Dr. Curtis and others, at the
Lick Observatory. Most comets hitherto observed
have given continuous spectra, due to reflected sun-
light, and a number of bright lines or bands, whose
nature varies from one comet to another and whose
identification has been a source of some controversy.
Most commonly these bands have been identified as
" hydro - carbon,"
since comparisons
of cometary spectra
with the spectrum
of defiant gas and
other hydro - car-
bons gave a very
close correspon-
dence in position
and appearance.
There is also a
banded spectrum
due to carbon mon-
oxide, and another
identified with cya-
nogen. The earlier
observations of
Pluvineland Baldet
indicated the pre-
sence of cyanogen,
and the absence of
continuous spec-
trum, but others
arrived at contra-
dictory results.
The presence of
carbon monoxide,
the doublets, twelve
of which onlv were detected by Professor Fowler in
the laboratory spectrum of this substance, was in-
dicated by twenty-one in Pluvinel and Baldet's
results, and these bands can be arranged into a series,
as pointed out by Professor Fowler, in a paper in The
Astrophy steal Journal. Additional demonstration of
their results is obtained from photographs taken by
Dr. Curtis, of the Lick Observatory (Figure 245), the
carbon monoxide spectrum being placed below that
of the comet for easy comparison. Out of the five
or six recent comets which have shown the low-
kind permission
Figure 245.
of Prvfissor A. Fezvlei, J-'.K.S.
Comet Morehouse (1908 c) March 20th, 1909.
Upper part of figure, Objective spectrogram 7h H. D. Curtis, Santiago,
Chile. Lower part of figure, spectrogram of Carbon monoxide, pressure
0-01 mm. A. Fowler, South Kensington.
pressure carbon monoxide spectrum, it was only in
this comet that the bands were bright in the head
as well as in the tail. Observations by Campbell
and Albrecht, at Lick, showed the " presence of
carbon and cyanogen, though the" second cyanogen
band was apparently absent. New radiations
suggested as due to nitrogen and other substances,
also, were suspected from some photographs.
Professor Newall
has suggested that
the apparent simi-
larity in the spectra
of many comets
is not so much due
to a similarity in
the materials of
which the}- are
composed, as to
the fact that these
" hvdro - carbons,
nitro-carbons, &c,"
are present in the
regions near the
sun through which
the comets pass
and are " rendered
incandescent by
some processes'
connected with the
motion of the solid
parts (including
dust) of the head
of the comet
through the va-
pours, or with the
emission of some
influence from the comet head."
In comets, as has been suggested by more than
one writer, we seem to have the development of light
without sensible heat, phenomena of luminescence ;
the repulsion of their tails by the sun is attributed to
the agency of light-pressure, though other theories
have been invoked also. The action of the resisting
medium upon the orbits of these bodies, and possibly
upon the materials of their tails, is another point
about which we are gradually gaining additional
information.
CORRESPONDENCE.
CONSIDERATIONS ON THE PHYSICAL
APPEARANCE OF THE PLANET MARS.
To the Editors of " Knowledge."
Sirs, — The article by Mr. E. M. Antoniadi on the above
subject in your last issue contains statements which I think
should not pass without comment. The interesting questions
arising from the markings on the planet Mars and the true
nature of the markings themselves are by no means so con-
clusively settled as is assumed by Mr. Antoniadi in his
article.
He has stated only one side of the case, and to my mind the
arguments of the advocates of what Mr. Antoniadi calls " the
canal myth " have not been properly stated or answered. It
is, I think, well that readers of " Knowledge," some of
whom may have had no previous acquaintance with the
subject, should know that the matters contained in Mr.
Antoniadi's article are not established truths.
I have never before seen it stated that " canals " appear
straight and not curved at the edge of the disc. It has been
my own experience that no markings, of the nature of canals
or otherwise, can be seen near the limb of Mars, owing,
obviously, to the planet's atmosphere ; and I had previously
understood that this experience was universal. It is stated in
the article that Mr. Denning could see, with his ten-inch
reflector, the true nature of the Martian canals. Is it not
June, 1913.
KNOWLEDGE.
239
extraordinary that Professor Lowell with his twenty-four inch
refractor has apparently failed to do so ? The following
passage, " areographers forget . . . that what is clear and
sharp on such a small disc so far off ought to be represented
as exceedingly vague on drawings three inches in diameter,"
possibly supplies an explanation of the apparent telescopic
blindness of certain observers. This is what the statement
amounts to : You may see a system of sharply defined lines
on the disc of Mars, but when representing them in a drawing
you must give them an uncertain foggy appearance. If you
are sketching a distant balloon, and can quite distinctly see all
the ropes as very fine sharp lines against the sky, you must
represent them in your sketch as vague, uncertain bands.
I am afraid that I must, with all respect, disagree with the
following passage on point of fact : " The student who passes
many consecutive hours in the study of Mars with medium-
sized instruments is liable to catch rare glimpses of straight
lines, single or double, generally lasting about one quarter of
a second." I have myself studied Mars with a nine-inch
reflector, and have seen and held for considerable periods
several of the larger " canals." The sensitiveness of observers
varies very much, and also the visibility of " canals " is not
always the same. It is a mistake for any one observer, how-
ever practised, to take his own experience and apply it to
observers in general. Bearing in mind the great fluctuations
in visibility of the markings on Mars — and indeed markings
which come out strongly at one season will be practically
invisible at another — the contrasts shown in Figures 190 to
193 lo?c some of their point. Mr. Antoniadi pours great
ridicule on the advocates of comparatively small telescopes.
He discusses this by no means settled question as if aperture
were the only thing to be taken into consideration. In order
to counteract the effects of the secondary spectrum, the
greater the aperture of a telescope the greater must be its
focal length. With telescopes of very great aperture it has
proved, so far, a mechanical impossibility to make the focal
length sufficiently great. In the perception of the existence of
faint stars and strands of nebulosity, for which these tele-
scopes of great aperture are especially suited, exact definition
is not important ; but in the case of planets, perfect definition
is of more importance than light-grasp.
Definition depends, too, not only on the telescope, but also
to a' very large degree indeed on climatic conditions, which
Mr. Antoniadi has not taken into account in his article.
Professor Lowell has, at the Flagstaff Observatory, probably
the finest possible equipment for planetary work. The
climatic conditions at Flagstaff are undeniably better than
those enjoyed by any other observatory. His twenty-four-
inch refractor is, as refractors go, optically perfect. In
planetary work his best results are obtained with the aperture
stopped down to eighteen inches. The results obtained by
Professor Lowell in planetary work are a testimony to the
advantages of his observatory. His photographs of the
planets, notably of Saturn and Jupiter, are, I believe,
admitted to be unequalled. Professor Lowell is the greatest
advocate of the theory of the artificial origin of the canals.
He has succeeded in obtaining photographs of Mars on which
canals appear. Yet Professor Lowell, who, with every
advantage and equipment, has made the study of Mars the
chief work of his life, and who certainly has more right to
speak upon the subject, as an observer, than any other
astronomer, is not mentioned by Mr. Antoniadi in his article.
84, Dartmouth Road, J. E. MAXWELL.
Brondesbury, N.W.
THE DOUBLE (AND BINARY) STARS.
To the Editors of " Knowledge."
Sirs,- — There are some statements in Mr. Henkel's paper
in April " Knowledge " that require qualification. He writes:
" T.he c?iscs 'of stars> tnat is) seen by the naked eye, being
optical illusions, are effects of irradiation." Now, no one sees
" discs " with the naked eye at all ; as is well known, they are
only seen when magnifying power is applied. Moreover, they
are not effects of irradiation at all, but of " diffraction " — inter-
ference phenomena, in fact.
He says that Herschel said, in his own words, " he went
out like Saul to seek his father's asses, and found a kingdom."
It was not Herschel who said this, but Schwabe, and it was
said in relation to the discovery of the periodicity of sun-spots.
Mr. Henkel says : " Perhaps as many as twelve thousand
such couples are known," meaning double stars. There is no
"perhaps." Burnham's list contains thirteen thousand six
hundred and fifty-five. Re catalogues, neither Struve's'
" Mensurae " nor Lewis's Catalogue is now the standard
authority, but Burnham's.
There are other too positive statements upon matters where
facts are doubtful and opinions differ, but I pass over merelv
doubtful assertions. EDWIN HOLMES.
THE FOURTH DIMENSION.
To the Editors of " Knowledge."
Sirs, — I have no desire to quarrel with Mr. Henkel's
tentative "working definition" of "reality" as "that which
exists independently of any human mind perceiving it." But
I would qualify "reality" so defined as "objective," i.e.,
universally valid ; for we obviously cannot deny reality to our
individual ideas, though we may usefully distinguish between
this reality, which is subjective, i.e., only true for the individual,
and that which is " objective," as defined above. And I
would add that, in order to conceive of a world existing
independently of any human mind perceiving it, we must
conceive of it as existing in some other mind. So that
Mr. Henkel's definition does not answer my objection.
Concerning the objects of vision, Mr. Henkel's position is
not easy to state in philosophical language. He appears to
argue that our visual percepts arise from the same causes as
our tactual percepts, and that in order for any such cause to
give rise to a two-dimensioned visual percept, it must be
capable of giving rise to a three-dimensioned tactual percept.
This may, indeed, be true. But its truth or falsity does not
affect the argument, because in either case the fact remains
that the objects of vision (i.e., the visual percepts) are two-
dimensioned. And Mr. Henkel's objection to my theory of
the fourth dimension was that it was built upon the assumption
of the existence of objects having less than three dimensions,
which Mr. Henkel said did not exist. But vision does
immediately acquaint us with two - dimensioned objects.
Whether the causes of our visual percepts are capable of
producing three-dimensioned tactual percepts is a question
which does not affect this fact. The existence of such causes
is an inference and is not given immediately by experience.
But, indeed, Mr. Henkel admits the existence of a one-
dimensioned object of experience, i.e., time, and thus seems
himself to demolish his objection to my theory.
The Polytechnic, H. S. REDGROVE.
Regent Street, W.
P.S. — As I have already intimated, I do not intend to dis-
cuss the question further with Mr. Johnston, but I must correct
two misstatements in his letter. In the first place, my letter
in your February issue was not written, as Mr. Johnston says,
to express surprise that he had not gone into more detail in
his former letter, but to point out that as he had not taken, and
would not take, the trouble to acquaint himself with the
arguments upon which my theory was based, he was incom-
petent to criticise it. In the second place, Mr. Johnston is in
error when he says that in my letter in your March issue I
gave my " argument in more detail, so it is possible for more
criticism to be made." What I merely did in that letter was
to answer objections raised by Mr. Henkel. If Mr. Johnston
really wanted my argument in more detail, he could have
found it at the references I gave. If he had done that it
might have been possible for him usefully to criticise the
theory in question.
PROBLEMS OF LIFE AND REPRODUCTION.
To the Editors of " Knowledge."
Sirs, — I hold that it is rank impertinence of an author to
controvert the judgment of the critic. It is, then, merely a
matter of interest to note that after about a dozen criticisms
240
KNOWLEDGE.
June, 1913.
of my Problems of Life and Reproduction," many in lay
papers, the first to tax my writing as " a bit over technical and
involved" should be the writer in " KNOWLEDGE." But he
continues : ' We have been most interested in the article on
the transmission of acquired characters ; but we are somewhat
disheartened by a footnote at the commencement to the effect
that another author has collected a number of facts in favour
of this theory since the first appearance of this article, which
ought surely to have afforded sufficient reason for rewriting."
From this presentation it might be supposed that the tendency
of the article was against the theory ; but that additional
evidence has accrued on the same side since an article in
favour of a certain view was written is surely no reason for
rewriting it, only for indicating what is the nature of the
additional support. Now this is precisely what I have done.
The preface, dated August, 1912, at the time of the paging of
the corrrected galley slips, into which large additions were
introduced, states: "In the revision, indeed, I have endeav-
oured to bring everything up to date, and have not hesitated
to do so, without note or comment, wherever no question of
priority was involved ; but where this was the case I have
pointed it out by the inclusion of new matter in square
brackets, [ ] , according to established custom."
The footnote to which " R. L. " refers deals with a paper of
Semon's, of 1911, which is in the nature of a " Bericht." On
page 189 of this essay will be found bracketed a statement of
evidence published in the Mendel Jubilee Volume of that same
year. Another point is illustrated by an added footnote
(page 195), utilising the views of Professor Dendy in his
" Evolutionary Biology," which appeared in 1912. A post-
script deals with an argument of Sir Ray Lankester's, which
appeared in the Encyclopaedia Britannica in 1911. In fine,
the whole of the essays were revised, added to, retrenched, or
rewritten (one of them, as stated in the Preface, almost
completely so), in order to bring them up to date. Neither
Mr. Murray nor I would have been satisfied with any revision
stopping short of this in a volume of the " Progressive Science
Series."
Such matters as these are not matters of the personal
judgment of the critic, but of the conscience and conscientious-
ness of the author criticised. You will, therefore, I am sure,
allow me to set myself and my publisher right in the eyes of
your public.
~ MARCUS HARTOG.
University College, Cork.
HORNETS AS PETS.
To the Editors of " Knowledge."
Sirs, — I read with much interest the paper by Mr. G.
Hurlstone Hardy on the above subject. When a boy I kept
many colonies of Hornets, Wasps, and Humble Bees, and
can confirm Mr. Hardy's statement that they may be adopted
as pets with very little danger. I used to bring broods home
from the fields, queens and all, and place them in properly
prepared holes in the grassy bank which I made in the garden.
I had some very strong families of them, and spent many
hours every day sitting as close to them as I possibly could
and counting the numbers flying in and out hourly. In this
way I could gauge their daily increase of strength and it was
astonishing how they multiplied. By watching them closely
many little facts were learnt concerning their habits ; but all
these are probably well known ; though I have never read a
book descriptive of these insects.
They are very far from being savage or aggressive if treated
in a proper manner ; they are very industrious, but, if
molested, can be fierce and swift to use the terrible means
which Nature has provided for their protection. They are
most interesting creatures and capable of furnishing many
hours of recreation and instruction to students. I shall never
forget the regret I felt when paternal admonitions led me to
destroy my favourites. Neighbours, however, could not stroll
in their gardens without a cloud of my hornets and wasps
hovering threateningly around their heads, and serious repre-
sentations being made to that effect I had to remove the
menace.
Hornets are like certain other supposed vicious things in
animate nature. If allowed to pursue their own way without
interference they are rarely the assailants. People are not
always just to creatures endowed with powerful means of self-
defence. We are apt thoughtlessly to obstruct them and
then, should we suffer for our temerity, usually put the blame
on the wrong shoulders. Hornets and wasps are capable of
good as well as harm ; but they carry nasty weapons, and so
the public regard them as fit objects for extermination.
I have great regard and respect for these insects ; they
merit more considerate treatment and it is painful to see that
thousands of the poor queens are hunted down and killed
every spring for a paltry compensation.
W. F. DENNING.
Bristol.
NOTICES.
INSECT LIFE. — Messrs. Jack announce a new and com-
prehensive work on "Insects: their Life- Histories and
Habits," by Harold Bastin. Written in plain language and
thoroughly up-to-date, the work covers the whole field of
insect life, and will be profusely illustrated in colour and black
and white.
GREAT WESTERN RAILWAY.— No railway claims more
attention nowadays than the Great Western, which is the
subject of the latest volume in Messrs. A. & C. Black's
" Peeps at Railways " Series. The author, Mr. Gordon Home,
has given a very readable, informative, and exhaustive account
of the history and the present activities of the line and of
many of the places of industrial and historical importance
that it serves. The work is fully illustrated in colour and
black and white.
THE LEITZ OPTICAL WORKS.— In connection with
the completion of its 150,000th compound microscope, the
firm of Ernst Leitz has issued an interesting pamphlet, giving
portraits of its present members and some remarkable details
showing the development of its work at Wetzlar. The estab-
lishment was founded in 1849, but it was not until the present
senior partner acquired control of the business in 1870,
that rapid progress began to be made. At that time the annual
output of microscopes was about sixty, in 1881 it was six
hundred, in 1903 six thousand, and now this number has been
doubled. The 100,000th Leitz microscope was presented to
the late Professor Koch in 1907, and the 150.000th has now
been given to Professor Erhlich of Frankfort-on-Main. Corre-
spondingly, the staff has increased in number since 1870, when
twenty persons were employed, until now it consists of nearly
one thousand workers.
THE ALCHEMICAL SOCIETY.— The fifth General
Meeting of the Alchemical Society was held on Friday, May
9th, at 8.15 p.m., at the International Club, Regent Street,
S.W. The chair was occupied by the Honorary President,
Professor John Ferguson, M.A., LL.D., F.I.C., F.C.S., of
Glasgow University (whose monumental bibliography of
alchemical works is well known to students), and a paper by
the Venerable J. B. Craven, D.D., Archdeacon of Orkney, was
read, entitled " A Scottish Alchemist of the Seventeenth
Century : David, Lord Balcarres." The paper contained
particulars concerning the life of Lord Balcarres and hinted
at the possibility of Rosicrucian sympathies. The author has
been permitted to examine what remains of Balcarres'
library, and has found therein a manuscript translation of the
famous " Fama Fraternitas," antedating the earliest published
translations. The paper also contained particulars of other
interesting manuscripts in this library, and concluded with an
old Fifeshire legend showing the fantastic views which were
once held concerning the Rosicrucians.
The above meeting was followed by the Annual General
Meeting of the Society. It is interesting to learn from the
Secretary's and Treasurer's reports that the membership is on
the increase and that the finances of the Society are in a
satisfactory condition.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
JULY, 1913.
EDITORIAL.
Seeing that many of our readers find it trying — especially in artificial light — to read " Knowledge "
owing to its being printed on art paper, we have decided to make a change. Henceforth a surface which
is not highly glazed will be used for the letterpress ; but justice will still be done to the illustrations by
putting them on the paper which has recently been used for the whole Magazine. Under these circumstances
it becomes necessary to point out to our contributors that illustrations which are to be inserted in the body
of the text must be line drawings, while those in tint or photographs which are to be reproduced for the
plates must be suitable as to size, and those which are to go on the same page should be as similar as
possible in character.
We take this opportunity of thanking all those who have been helping us to carry on the Magazine
and of asking our readers to make suggestions as to articles, especially when they can indicate where
suitable material is to be found. Particularly should we welcome astronomical photographs and drawings
which would be suitable for plates, and illustrated descriptions of original work which is of general as well
as special interest.
As we have said on previous occasions, we are always ready to hear from our subscribers who have
anything to say with regard to the improvement of the Magazine, and also as to what features at present
existing might with advantage be emphasised. It is obvious that the larger the circulation the more money
there will be to spend on the Magazine, and in conclusion the Editors invite everyone who takes a general
interest in the paper to cooperate with them and to do something to make it more useful and more widely
knpwn.
241 a
THE FOURTH DIMENSION AND ITS BEARING ON
THE CAUSE OF UNIVERSAL GRAVITATION.
By A. G. BLAKE, F.R.A.S.
Our ideas of the dimensions of a body are very
largely derived from the circumstances in which
these dimensions may undergo variation. Thus we
speak of a piece of paper as being of two dimensions
because of the great difficulty of changing its thick-
ness compared with the difficulty of changing its
length or breadth.
In " flatland " — a hypothetical region where
motion confined to two dimensions only is possible —
it is quite conceivable — nay, it is a necessary assump-
tion if we are to allow the possibility of concrete
bodies in it — that bodies should have a certain
thickness in a third dimension which would be
invariable in individual bodies, but not necessarily
uniform among different bodies. Thus the sum
total thickness of bodies in " flatland " would be
fixed and invariable. To the inhabitants, who would
be incapable of realising thickness, this would result
in the conservation of some physical attribute
peculiar to bodies of two-dimensional space.
In seeking evidence of a fourth dimension, then,
we must draw our inferences from the conservation
of some physical attribute peculiar to three-
dimensional space. The most obvious — indeed, the
only one — is the Conservation of Mass. We cannot,
however, infer that mass is the three-dimensional
perception of a four-dimensional thickness ; for the
mass of a body is directly alterable by changing its
three known dimensions by simply cutting or
breaking the body. If we change only three
dimensions of a four-dimensional body the fourth
must remain unchanged. Suppose (L), (B), (T) to be
the units of length, breadth, and thickness, (M) the
unit of mass and (F) the unit of " fourth dimension."
Then, since mass varies directly as volume,
(M) = m (L), (B), (T), when m is some constant.
But since the fourth-dimensional unit is a constant
for any one body, and (F) is the unit, we may put
Therefore (F) =
(M) = (F), (L), (B), (T).
(M)
(L), (B), (T)
volume
But
mass
volume
is what we call density.
Accordingly, in our three-dimensional universe
every body has a thickness in a fourth dimension,
which is variable in different bodies, but invariable in
the same body, and that fourth-dimensional thick-
nest is the body's density.
That this fits in perfectly with analogies drawn
from two-space is easily shown. Thus in " flatland "
we may consider a two-dimensional body with
a small thickness in the third dimension. A
" flatlander " would cut down its length and its
breadth, but would be powerless to alter its thickness,
so that its volume would vary as its area. Extend-
ing this to three-dimensional space, we may cut down
a body in three dimensions — length, breadth, and
thickness — but we cannot alter what we may call its
fourth or extent in a fourth dimension, so that its
mass varies as its volume. In fact, mass in four-
space corresponds to volume in three-space and
area in two-space. The volume of a three-
dimensional body is infinity times as great as the
volume of a two-dimensional body. The mass of a
four-dimensional body is infinity times as great as
the mass of a three-dimensional body (i.e., one
whose density is nil).
Though we cannot directly change the extent of
a body in its fourth dimension we can do so indirectly
by taking advantage of the principle of the conserva-
tion of mass and compressing the body in three
dimensions. The two-dimensional equivalent to
this is that in two-space, though it is impossible
directly to alter the third dimension ; yet by
compressing it in two dimensions the third will be
increased, while the volume will remain constant.
For in two-space the chief physical principle would
be the conservation of volume, though under what
aspect volume would present itself to " flatlanders "
we can never tell.
Having shown how a body's density ma)' be our per-
ception of its thickness in a fourth dimension, I shall
endeavour to explain the cause of Universal Gravita-
tion— why any two bodies in space will attract each
other, and why the force of attraction will vary
directly as the mass and inversely as the square of
the distance separating them.
For the purposes of my theory I assume that
matter is surrounded on all sides by an ether of vast
extent in every direction — in all four dimensions. I
shall show hereafter that the very great density
implied in the last clause is not incompatible with
absence of gravitation power. In this ether an
immense number of waves is being propagated in
every possible direction ; the waves themselves may-
be small, but their number renders them capable of
exerting a finite and constant pressure at every
point. Consider a body poised freely in space. For
simplicity let it be a homogeneous sphere. This
body will cast a penumbral shadow (if I may call it
so when light-waves are not involved) out into space
in every direction. As an example, I will take the
242
July, 1913.
KNOWLEDGE.
243
case of a body situated near the centre of a hollow
sphere, the inner side of whose shell is aglow with
light. Consider a particle distant d from the body,
where d is infinitesimal compared to the radius of the
illumined sphere. Now the diminution of light
occasioned by the body as seen from the particle
is obviously proportional to -p. Now consider a
similar system in the ether I have postulated. Let
the body be A and the particle p. Then the
diminution of pressure along Ap occasioned by the
interception of waves by the dark bod)- is pro-
portional to -75 . But since the waves come in every
direction and in all/our dimensions, the diminution
is also proportional to the length, breadth, thickness,
and " fourness " of the body A. Therefore, the
pressure along Ap (taking sense into account) is
(k-^M)
But the pressure on p from the other side in the
opposite direction pA is equal to K.
Accordingly the particle is being pressed towards
the body A with a force equal to
-("-*)
XM
7'
when X is a constant.
a force directly proportional to the mass and
inversely proportional to the square of the distance.
It is perfectly plain from the foregoing that the
ether might be possessed of great density, since it
bears the waves which cause gravitation itself, and
therefore obviously cannot gravitate.
This theory also accounts for the instantaneity of
gravitation. The most refined observations have
failed to disclose any lapse of time between cause
and effect where gravitation is concerned, and this
would be wholly inconceivable were gravitation an
inherent property of matter.
THE NEW ASTRONOMY.
MEETING OF THE PHYSICAL SOCIETY.
Except for the time spent on a paper on wireless detectors,
the whole meeting of the Physical Society on Friday,
May 30th, was occupied by a lecture by Professor Bickerton
and a discussion on his theory of the origin of new stars.
The lecturer began by showing that so many agencies tended
to bring about stellar impact that these events must be scores
of thousands of times more frequent than mere chance
encounters would suggest. In fact, the impact of suns must be
an important cosmic law. He then showed that all collisions
of suns brought about by gravitation must be oblique ; that
is, of a grazing character. Some fifty years ago Dr. Johnstone
Stoney had deduced this fact. It was accepted by Lord
Kelvin, Sir Robert Ball, and Arrhenius. These eminent men
had traced out in some detail the results that they thought
would ensue. Owing to an oversight their work was valueless.
They did not detect the fact that in solar grazes the shearing
force available was millions of times greater than that neces-
sary to cut the most tenacious of nickel steel, and that
consequently grazing suns tear one another and the parts
actually meeting coalesce to form a third star of such extreme
thermodynamic intensity as to be explosively hot. Hence the
problem of the encounter of suns must be taken in two parts :
the new third star and the torn bodies of the suns.
Professor Bickerton then showed that the problems of all
cosmic encounters must be divided, whether the collisions be
between dense bodies such as suns or rare such as nebulae,
meteoric swarms, or interpenetrating sidereal systems. In
each case a central furnace, an explosively hot third body,
must be formed. It was then shown that in any explanation
of novae three most extraordinary criteria had to be satisfied.
These were the thermodynamic intensity, the complex light-
curve, and the long series of abnormal spectrograms. Every
one of the current hypotheses failed in at least two, and most
of them failed utterly in all three, criteria.
The induction that every nova is a third star torn from
grazing suns satisfies all three criteria in the utmost minutia
of detail. By the process of exhaustion this theory was the
only explanation left. The shearing force available might be
based on a velocity of two hundred and fifty miles a second, a
velocity five hundred times that of a Krupp shell ; that is, an
energy of unit mass or kinetol a quarter of a million times
that of our swiftest projectiles. The surface to be sheared is
proportional to the square of the diameter of a sphere, whilst
shearing force is as the mass ; that is, as the cube of the
diameter ; and as the mass of the suns is quadrillions of times
that of any military projectile there remains no question but
that grazing suns shear one another. According to Dr.
Crommelin, Nova Persei was estimated to have a maximum
intensity ten thousand times that of the Sun. That is, were
this tremendous blaze kept up by fuel, it would require to be
stoked with six million times the entire coalfields of the earth
• each minute of its maximum. The impact of suns is the only
known source of such a suddenly developed store of energy.
Professor Bickerton next pointed out that the third star
would be formed in an hour, would expand, and would
dissipate, giving a light-curve with a sudden uprise as novae
always exhibit, whereas the commonly received explanation of
Seleger and Halm, that of a sun entering a nebula, must
give a light-curve almost horizontal. The explanation given
in the lecture followed that in " Knowledge " (September,
1911), as did also the explanation of the series of spectrograms,
Professor Bickerton stated that although such physical
agencies as pressure might account for some of the peculiarities
of the spectra of novae there was no need to bring in
anything but the Doppler principle. This, taken in conjunction
with the deduced properties of the third star, was sufficient to
account for any physical fact even of so complex spectra as
those of Nova Geminorum as obtained at Cambridge.
The Chairman, Professor Schuster, F.R.S., stated that the
whole theory was extremely suggestive, and that Professor
Bickerton had devoted a third of a century to its study.
There was one point he should like discussed, and that was the
high velocity of hydrogen referred to. Experimentally it had
been shown that, no matter how enormous the pressure to
which the gas was subject, the velocity of escape never rose
above that of sound.
Professor Bickerton replied that the velocities observed in
novae was a question of temperature, not pressure. The
velocity of sound was a question of thermodynamics. If the
compressed hydrogen had the enormous temperature attained
during and subsequent to the collision the velocity of sound
would be proportionally increased.
A hearty vote of thanks was accorded to the lecturer.
THE MAKING OF A MICROSCOPE.
By WILFRED MARK WEBB, F.L.S.
With Illustrations from Photographs specially taken by Messrs. Lascelles & Co.
The microscope has come to be used in so many
branches of scientific research, and, we may add, of
everyday commerce, that it has occurred to us that
a short illustrated account of the way in which the
instrument is made would be of interest to our readers.
Accordingly Messrs. W. Watson & Sons were ap-
proached, and they kindly gave permission for their
works at High Barnet to be visited, and afforded
all the necessary facilities for taking the photo-
graphs from which our illustrations have been made.
The work may well be divided into two parts, and
we may consider it under two headings : firstly, the
making of the metal stand and fittings ; and secondly,
of the optical parts, or, in that slang which the Royal
Microscopical Society is content to use, "brass" and
" glass." Figure 246 shows a general view of the
machine shop where the metal parts of microscopes,
and also of telescopes, field glasses, and so on,
are got into shape. It may be said at once
that the rough castings (see Figure 250) are
not made at the works. The first process
through which the foot, for instance, of a microscope
is put is grinding, by which the fiat surfaces are
made true, as shown in Figure 247.
The surfaces which cannot be ground are milled
that is to say, cleaned up in the machine provided
with a revolving wheel furnished with a number of
cutting teeth (see Figure 249).
At the back of the machine shop is a room con-
taining the forges and also an interesting machine,
shown in Figure 248, which gives a very great
mechanical advantage, by means of which the brass
tubing used for the bodies of microscopes and other
instruments is brought to the exact size required ;
the tubing is pulled over a metal core of the exact
diameter which is required through a hole in an iron
plate which corresponds with the outside measure.
It may be added that the tubing is made smaller
during the operation and is lengthened considerably,
while its hardness is very greatly increased.
Turning to other parts of the microscope stand it
is not necessary to describe the turning and screw-
cutting in connection with various fittings ; but to
give some idea of the accuracy which has to be
obtained it may be mentioned that in the case of
the screw-threads in telescopes which are made for
Government an error of only ± -0005 of an inch is
allowable. In a smaller shop special work is done.
For instance, it is found necessary, when making the
surfaces true which are to be moved by the fine
adjustment of the microscope, that this should be
done on a planing machine worked by hand, as
shown in Figure 251. The processes of blackening
and bronzing differ but little, if at all, from those in
use in the case of other metal work, and we may
leave the making of the stand on one side for a
moment to consider the very important question of
lens grinding.
The special optical glass which is imported for
the purpose of lens-making is received in small slabs,
of which half a dozen are shown in Figure 252.
These are slit up into pieces, which are of the
required thickness and size, by means of an apparatus
similar to that used for slicing precious and
ornamental stones. It is, for all practical purposes,
a circular saw in the form of a revolving metal
disc, the teeth of which consist of diamond dust
hammered into its edge. The machine and discs
used are represented in Figure 253, where a block of
glass partly sawn through is seen in position.
The next operation is to trim up the square pieces
of glass so as to make them approximately circular
by clipping them with shears. They are then
ground or roughed into shape (see Figure 254), and
afterwards taken to the glass shop, a view in which
is seen in Figure 261. Here the larger lenses for
eyepieces and low-power objectives are polished and
made true, and we illustrate the details of the
process in Figure 255, where blocks of lenses are
seen, showing how convex, concave, and plane
surfaces are produced. The polishers are fastened
to a crank which causes them to rotate with the
particular motion required. It should be mentioned
that fine rouge is used at this stage.
Small microscope lenses are fastened on to a block
in the same way and held by the hand into a
revolving cup, as seen in Figure 256, while very
small ones for high-power objectives are fixed singly
to handles and polished individually. A pair of
holders may be seen lying on the table in the figure
just mentioned.
From time to time as the work proceeds the lenses
are tested with a proof plate, the surface of which,
in the case of convex lenses, of course, will be con-
cave, and vice versa. The method of applying this
is seen in Figure 257 in the case of a good-sized
lens, and the proof that the latter is accurately
ground is shown when it is brought into contact
with the plate by the formation of a perfect series
of Newton's rings. After the lens is polished its
edges have to be ground, and we illustrate this in
Figures 258 and 259 in the case of a large lens, and
also that of one which is to be used in the making of
a one-twelfth objective. Putting together one of the
latter is,of course, a most delicate process and requires
great skill. The flint and crown glass constituents
of the lenses have first of all, as in other cases, to
be cemented together and then the whole series has
to be mounted in the metal fittings and adjusted.
This is done at Messrs. Watson & Sons' works by
means of measurements, with the result that very
few of the finished objectives, which are turned out
in considerable numbers, do not pass the test the
first time.
Now we may consider that we have all the parts of
244
July, 1913.
KNOWLEDGE.
245
Figure 246.
The machine shop at Messrs. W. Watson & Sons' Works, High Barnet.
Figure 247.
Making flat surfaces of a casting true
with a grindstone.
Figure 248.
The machine for drawing out
brass tubing.
Figure 249.
Milling or cleaning up the parts of a
casting.
246
KNOWLEDGE.
July, 1913.
Figure 250.
Rough castings as received at the works.
Figure 252.
Optical glass as imported.
Figure 251.
Planing the surface of a fine adjustment by hand.
Figure 253.
Machine for slitting the glass.
Figure 254.
Roughing or getting the lenses into shape for polishing.
Figure 255.
Lens polishing machine with blocks of lenses.
July. 1913.
KNOWLEDGE.
24:
Figure 256.
Grinding small lenses by hand.
Figure 258.
Grinding the edge of a finished lens of considerable size.
Figure 257.
Testing a lens with a proof plate.
Figure 259.
Grinding the edge of a lens for a one-twelfth objective.
248
KNOWLEDGE.
July, 1013.
Figure 260.
Mounting the lenses for a one-twelfth objective.
Figure 261.
A view in the glass shop.
x * l^'^
Figure 262. A microscope stand (H Edinburgh Student's) with its components and their individual pieces.
Figure 263.
Assembling a microscope.
Figure 264.
The testing-room examination.
July, 1913.
KNOWLEDGE.
249
the microscope ready, and to give some idea of how
many of them there are we show in Figure 262 the
more important portions of an H Edinburgh
Student's Microscope and the separate pieces of
which they are made up. It may surprise some of
our readers to learn that there are sixty-four of
these and ninety-six screws in the stand alone.
To assemble a microscope is the term used for
putting the stand together — that is, combining the
stage, foot, limb, and mirror (see Figure 263). After
this the instrument has to go through the testing
room examination (see Figure 264), when it is ready
to leave the works and be fitted with such eyepieces
and objectives as its future owner needs for his work.
CORRESPONDENCE.
QUADRATURE OF THE CIRCLE.
To the Editors of " Knowledge."
Sirs, — In " Knowledge " for November last you published
a letter from me touching the quadrature of the circle. In
this letter I asked certain questions on the subject. I also
stated that I had ascertained by geometry that the perimeter
of a circle is equal to a certain triangle described on same.
Up to date no reply to the questions referred to has
appeared in " Knowledge," and I am still holding in
abeyance the geometric solution referred to pending satisfac-
tory answers from some source to these queries.
What I wish to be informed on is : —
1st, Has the solution referred to above ever been published or
made known before it appeared in " Knowledge," i.e..
either in ancient or modern works ?
2nd, Has it ever been satisfactorily proved or disproved in
any way by any author ?
One gentleman did write to you on the subject, but he
made no reference whatever to these questions, although he
criticised the solution.
In reply to this writer I give Figure 265, showing that the
solution is exact and not approximate only.
Arithmetic of the Quadrature.
I also send Figure 266 for the purpose of showing that my
geometric solution referred to above can be verified by
arithmetic.
Attention may be drawn to the following points : —
1st, The whole of the ratios given are based on the square
root of 5 and the square root of 1 (which, of course, is l),and
that they are therefore commeasurable.
2nd, The ratio of the circumference of the circle to its
diameter is identical with the ratio of —
(a) The area of the outer circle, minus the square to
(6) The area of the square, minus the inner circle, i.e.,
the ratio of (a) to (6) or of E to D in the diagram.
Table 46 shows the results of using any different ratio from
v^X v'l:
Figure 265.
By ordinary geometry the square C is = A and B together.
Let diameter = 1.
The square A = 1.
And square B = -25.
And therefore square C = 1 - 25.
Also square on E D F will = 5 (1-25 + 4).
And square on E F will = 1.
Therefore E I) F = v 5 and EF= \ 1.
And therefore E D F E = \ 5 X \ 1 .
A The inner circle-area v'5 + v'l + -25
(i radius).
B The square-area v 5 X \ 1 + E -5- 2.
C The outer circle-area v'5 X v'l +
v 2 + (-25 + \ 2).
D The four spaces D singly or together.
E The four spaces E singly or together.
Figure 266.
Ratios (taken inversely, etc.) :
Circumference to diameter ... v 5 X \ 1
E to D v 5 X \ 1
The square to the lesser circle v 5 X \ \ — 2
The greater circle to the square v 5 X \ 1-^-2
A to E •5XV'l+2-'
A to D v 5 X v'l X v'l
Table 46.
Ratio of Perimeter to
Diameter.
Area.
Spaces
E Equal.
Spaces
D Equal.
Ratio of E to D.
3
3,2
(v'5 X v'l) 3,236, etc.
3,5
•75
•8
• 809, etc.
•825
•875
•5
•6
•618, etc.
•65
■75
•25
•2
• 1909, etc.
•175
•125
2
3
USX v'l) -3236, etc.
•3714, etc.
6
These figures (and any further calculations that may be
made on the same lines) show conclusively that the figures of
the ratio " ^5X1 "are the most " symmctral " that can be
produced in conjunction with Figure 266.
Therefore, if they are not the true figures of the circle,
there must be some other figures or polygon (regular or
irregular) to which they do apply ; and it will also follow that
this other figure is a more symmetrical figure than the circle —
which is impossible.
On the strength of what I have advanced above, I hope
some scholar will now answer the questions given above.
Brisbane,
Queensland.
GEOMA.
THE FACE OF THE SKY FOR AUGUST
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 47.
Dale.
Aug.
Greenwich
Noon.
Sun.
R.A. Dec.
h. in. 0
8 51-9 N.17'6
911-1 16-3
9 30"i i4'8
948-8 13-2
IO 7*3 II '6
10 257 N. 9*8
Moon.
R.A. Dec.
h. 111. 0
9 48-6 N.i5'i
14 129 S. 17-1
18 55-9 S. 27-8
22 sS'6 H. 77
2 34 '6 N.19'3
7 2l"l N.27'0
Mercury.
R.A. Dec.
S 53-1 N 12-4
8 39'5 "3'9
8 32'9 15'S
8 377 16-7
8 54 '8 17*0
9 22'4 N. lO'l
Venus.
R.A. Dec.
5 48-3N.2i-i
6 1 2 'o 2 1 "4
6 36*0 21 '4
7 o'2 2i'3
7 24*7 20*9
7 49*2 N.20'2
Mara.
R.A Dec
4 6-i N.2o*i
4 19*9 207
4 33'6 21-3
4 47"2 21 "8
5 0*7 22'2
5 13-9 22'6
Jupiter.
R.A. Dt
18 417
■8 39-9
18 38-2
18 36-9
18 35-8
■8 35 -3
S.23'3
23 '3
23-4
b.33 4
Saturn.
R.A. De
56-8 N. 2t -o
58-7 21-1
0*5 21*1
2*1 21*2
3-6 21-2
4*9 N.21 "2
Ui;inus.
R A. Dec.
h. 111.
20 31-6
20 30*8
20 30*0
20 29*2
20 28-5
20 27*8
S. ig'6
19*6
19-7
19-7
19*7
S.ig-8
Table 48.
Date.
Sun.
r B L
Moon.
P
Mars.
P B L T
Jupiter.
P B I, I, T T
2 1 2
Greenwich
Noon.
Aug. 3
3
00 0
+ 11*7 +6*0 60*7
I3'6 6*3 354*6
15*4 6*6 288*5
17*1 6*8 222*4
18-7 7'o 156*3
+ 20*1 +7*1 90*3
0
+i8-3
+18-3
- 5'i
— 21 '1
-17-1
+ 7>
0 a o h. m.
-34'7 - 8-5 157-5 I 12 111
33'9 7'2 l°9'o 4 32 111
33'o 5-9 60-5 7 51 in
32'! 47 .120 11 11 111
3i'° 3'4 323'6 2 29 <r
-29-9 -2-2 275-3 5 48f
° = « • h. m. h. m.
-5'3 -i'6 M3'o 97'5 5 5'i ' 7 '5'
5't i'6 2i2'7 i29'i 4 2. e 6 23 e
4'9 1*6 282*3 i6o"6 11 58 tf 5 31 e
4'8 i'6 351-9 191-9 10 41 4 39<r
4'7 1 "6 61 '3 223*2 8 lof 3 47 e
-4'6 - r6 130-7 254*4 6 17 e 2 55 e
„ 18
,. 28
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto- (graphical latitude and longitude of the centre of the disc. In the case of Mars, T is the time of
passage of Fastigium Aryn across the centre of the disc. In the case of Jupiter, L± refers to the equatorial zone; L2 to
the temperate zone; Ti, T2 are the times of passage of the two zero meridians across the centre of the disc ; to find inter-
mediate passages apply multiples of 9h 5CUm, 9h 55lm respectively.
The letters in, e, stand for morning, evening. The day is taken as beginning at midnight.
The Sun continues his Southward march with accelerated
speed. Sunrise during August changes from 4.23 to 5.13 ;
sunset from 7.49 to 6.48. Its semi-diameter increases from
15' 47" to 15' 53". Outbreaks of spots in high latitudes should
be watched for.
Mercury is in Inferior Conjunction at Noon on August
4th; then it is a morning star, reaching West Elongation (18°
from Sun) on 22nd. Illumination increases from 0 to TV
Semi-diameter diminishes from 5i" to 3".
Venus is a morning star, having passed West Elongation
July 4th. Semi-diameter diminishes from 9" to 7". At
beginning of month § of disc is illuminated ; at end of month
J. Being North of Sun it is favourably placed for Northern
observers. It is 18' South of Neptune 30d Oh38mm.
The Moon.— New 2d Oh 58me; First Quarter 9d 4* 3" m ;
Full 16d 8h 27me; Last Quarter 25d Oh 18m m. New
31d 8h 38m t\ Perigee 3d llh e, semi-diameter 16' 36".
Apogee 19d8h m, semi-diameter 14' 44". Maximum Librations,
10d 7° W, 12d 7° N., 26d 7° E., 26d 7° S. The letters
indicate the region of the Moon's limb brought into view
by libration. E. W. are with reference to our sky, not
as they would appear to an observer on the Moon.
Table 49. Occultations of stars
by the Moon visible at Greenwich.
Date.
Star's Name.
Magnitude.
Disappearance.
Reappearance.
Mean Time.
Angle from
Angle from
N. to E.
N. to E.
I9I3-
h. m.
li. m.
Aug. 8
BAG 4814
6-5
8 33*
185°
8 53 ■'
2190
„ 12
Laciille 77 jo ...
7-0
10 II e
81
—
.. 13
BAG 6628
5'9
9 26 e
ICO
10 40 e
230
„ 15
X Capricorni
5-3
9 31 e
i°5
10 32 e
202
„ 18 -
BAG 8129
6'3
8 15 e
68
9 22 e
232
„ 19
BAC8184
64
1 9'"
117
3 42 '"
169
„ 20
BD-o°6
7-6
—
1 38 m
'79
„ 24
BD + 240599
6-6
—
—
11 41 1
225
„ 26
BD + 27°723
6-5
3 39 "'
52
4 46 in
280
,, 26
BAC 1848
5'6
—
IO 51 e
298
„ 26
136 Tauri
4-6
11 9e
157
II 22 J
189
., 28
47 Geminorum...
5'6
4 57 '"
120
5 59 "'
249
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
The grazing occultation of 136 Tauri on 26th should be carefully observed ; sometimes more than one disappearance or
reappearance takes place in such cases, owing to irregularities in the lunar outline.
250
July, 1913.
KNOWLEDGE.
251
Mars is a morning Star, semi-diameter 3$", defect of
illumination nearly a second. It is 1° North of Saturn,
24d 5he. It will reach Opposition early in January, so the
season of observation is commencing.
Vesta is in opposition August 4th, magnitude 6-1.
Ephemeris for midnight : —
R.A. S.Dec.
h ra o
August 2 20 59-3 ... 23-2
8 20 53-6 ... 24-0
14 20 48-1 ... 24-6
20 20 43-1 ... 25-1
It will be interesting to compare it with Uranus, which is
not far distant. Their magnitude is about the same, but their
aspect different.
Jupiter was in opposition on July 5th. Polar semi-diameter,
20V' in mid-August.
Table 50.
Day.
West.
East.
Day.
West.
East.
Aug. I
2
3
54
>•
Aug 17
(
D
234
,. 2
21
0
34
„ 18
13 c
J
24
• ) 3
(
J
1324
.» '9
32 (
J
14
., 4
3i
.)
24
,, 20
312 ;
J
4
.. 5
32
3
'4
,, 21
3 (
j
124
., 6
3'
)
4
2*
,, 22
12 (
j
34
.. 7
43
-)
1 2
,. 23
2 (
J
■43
,. 8
12
3
3
>•
,, 24
4 <
J
23 >•
., 9
42 1
"}
3
•• 25
41 !
•>
2
.. IO
4
>
125
„ 26
432
J
1
,, 1 1
4'3
N
2
., 27
43 l2 <
J
.. 12
432
J
1
., 28
43
J
12
.. 13
43'
J
*•
., 29
4'
?
3
., 14
43
0
12
,, 3°
42 (
J
'3
,. '5
21
J
3
4«
- 3'
4 <
J
23 !«
„ 16
2
3
43
E., 0h 35m 538m III. Ec. R., lh 9mm I. Sh. E„ 10h 26m 51'e
I. Ec. R. ; 5d0h33m«i II. Tr. E. ; 6d llh 0m 528e II. Ec. R. ;
7d 10h 15mc III. Oc. D., 10h 34me IV. Sh. E. ; 8d 0h 0mw I.
Tr. I., 0h 46ram I. Sh. I., 9" 18me I. Oc. D. ; 9d 0h 21m 36"m
I. Ec. R., 8h 44mc I. Tr. E., 9h 33me I. Sh. E. ; 13d 9h 3me II.
Oc. D. ; 15d8h 19me IV. Oc. D., 8h 42me II. Sh. E.. llh 6me I.
Oc. D., llh 14mc IV. Oc. R.; 16d 8h 14me I. Tr. I., 9h 10me I.
Sh. I., 10b32me I.Tr. E.,.llb 28me I. Sh. E. ; 17d 8h 45m 8'e I.
Ec. R.; 18d 10" 30me III. Sh. E. ; 20d llh 25rac II. Oc. D.,
22d8h27me II. Sh. I.. 9h 15me II. Tr. E., llh 18""e II. Sh. E. ;
23d 10" 3mc I. Tr. I., llh5me I.Sh. I.; 24d0h21ra/« I. Tr. E.,
7" 21"V I. Oc. D., 10h 40m 2*e I. Ec. R. ; 25d 7b 53mc I. Sh. E.,
10" 8"« III. Tr. E., llh9"V III. Sh. I. ; 29d 8h 49me II. Tr. I.,
llh 2mc II. Sh. I., llh 39°'e II. Tr. E., 30d llh 53me I.Tr. I.;
31d 8h 12m 5V II. Ec. R„ 9h llme I. Oc. D.
Meteor Showers (from Mr. Denning's List) : —
Radiant
Date.
K.A.
1
I )ec.
May 30 to Aug
ih
+
2S
Swift, streaks.
June to Aug...
31°
+
61
Swift, streaks.
„ to Sep. ..
335
+
57
Swift.
,, to Aug....
303
+
24
Swift.
July to Aug...
3„8
-
12
Slow, long.
July 25 to
Sept. 15
48
+
43
Swift, streaks.
|ulv to Sepl.
335
+
73
Swift, short.
[uly to Aug....
2 So
+
57
Slow, short.
Julv to Oct. ..
3>5
-t-
7?
Swift, short.
Aug. 10-13 .
45
a.
57
Perseids. Swift,
streaks.
.. 15
290
+
53
Swift, bright.
,, '5-25 ■•
291
+
60
Slow, bright.
„ 25
5
+
11
Slow, short.
Aug. to Sepi. .
353
-
1 1
Rather slow.
346
0
Slow.
Aug. to Oct. 2
74
+
42
Swift, streaks.
,, to Sept..
63
+
22
Swift, streaks.
Configuration at 9h 30me for an inverting telescope.
Satellite phenomena visible at Greenwich, ld 0h 31mm I. Tr.
The Perseids may be seen from July 19th, radiant 23° + 52°
advancing 1° per day in R.A.
Table 51. Non-Algol Stars.
Star.
Right Ascension.
Declination
Magnitudes.
Period.
Date of Maximum.
h. 111.
d.
T Herculis
18 6
+ 51 0
6"9 to 13
165
' May 2, Oct 1 }.
RY Ophiuchi
18 12
+ 3 '6
8' 2 to 13
>53'3
July 14.
W Lyrae
18 12
+ 36 b
7-3 to 12
196' 5
May 28.
RS Draconis ...
18 40
+ 74 '2
8 4 to 12
281
June 29.
SU Sagitiarii ...
.8 59
-22 -s
8 ■ 3 to 9
88
May 18.
R Aquilae
19 2
18-1
62 to 1 1
337
May 15.
\\ Aquilae
19 11
- 7 2
8-2 to 13
489
Julv 24.
K S;i<^ittarii
19 12
'9 5
70 to 13
269
Aug. 16.
T S^^iitae
19 18
+ '7 5
8 5 to 9-5
'5°'7
June 14.
Al' C.vgni
19 27
+ 46 0
7 O lo 80
94
May II, Aug. 13
TVCygni
'9 30
has 1
8 7 to 13
354
June 22.
R T A'juilae ...
19 34
+ 11-5
7'b to 12
325
Sept. 4.
RTCvgni
19 41
+ 48 \5
6 6 to 12
190-5
Mar 22.
TU Cygni
19 44
+ 4S S
8s to 14
225
July 21.
X Aquilae
'9 47
+ 4 2
8 2 to 10
348
Aug. 18.
KU Aquilae
20 9
+ 12 -7
7 9 t" 14
276
Aug. 22.
R Sagittae
20 IO
+ 16 • s
85 to 10
70-6
July 20, Sep. 29.
AI Cygni
20 28
+ 32-2
8 6 to 97
173
Aug. 27.
V Cygni
20 38
+ 47 '8
6-8 to 14
418
(une 29.
T Aquarii
20 45
5 '5
6 • 8 lo 13
202 7
July 30.
R Vulpeculae...
21 1
23 -5
7 1 to 13
136 8
Aug. 30.
T Cephei .. ...
21 8
+ 68 2
5 2 to II
387
Oct. 24.
S\V I'egasi
21 IS
+ 21 '6
87 to ?
17;
|uly 10.
YY Cygni
21 19
+ 42 -o
8 5 to 9 5
37§
Sep. 29.
S Cephei ...
21 36
78 2
7 0 10 1 ;
486
June 24.
V Pegasi
21 57
+ 57
7 '8 to 14
303
Sep. 8.
0 Lyrae minima Aug. 10d 7hra, 23d 4hm, Period 12d 21 -81' .
Algol minima Aug. 8J 4h 51m«», 13d 10h 29"V, 31d 3h 22mw, Period 2d 20-8h.
252
KNOWLEDGE.
July, 1913.
Saturn is a morning star, coming into a better position for
observation. Polar semi-diameter 8l". P. is — 4°-7; ring
major axis 41. i", minor 1 8 J". The ring is very widely open.
It is of interest to examine the exact amount of overlap
beyond the planet's pole.
East Elongations of Tethys (every fourth given), 4d
llh-7m, 12" lh-0m, 19" 2h-3e, 27"3h-6m; Dione
(ever third given), 5d 2h • 5m, 13" 7h • 7m, 21" 0h • 8e,
29" 6h ■ Oe ; Rhea (every second given), 6" lh • 7m, 15" 2h • 8m,
24" 3h • 8m. For Titan and Iapetus E.W. mean East and
West Elongations, I. Inferior (North) Conjunctions, S.
Superior (South) ones. Titan, 2" 5h • 7e W., 6" 5h ■ 3e S. ;
10" 8h • 9e E., 14" 9h • 4e I., 18" 6h ■ Oe W., 2" 5h • 6e S.,
26" 9h • le E., 30" 9h • U I. ; Iapetus, 20" 8h • be W.
Uranus was in opposition on July 29th. Semi-diameter,
lj". At end of August, 2° S.E. of p Capricorni.
Neptune is too near the Sun for observation, having
been in conjunction on July 19th.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which two
hours will overlap with the following one. Thus the present
list includes R.A. 18h to 22h, next month 20hto 0h, and so on.
CORRESPONDENCE.
Note. — We have received a communication from Dunford Bridge relating to Professor Thomson's note on
reproductive harmony in the wild duck (see "Knowledge," Volume XXXVI, number 538, page 187), and one
from "Old Planter," but as the writers have forgotten to attach their names, according to our rule, we are not
able to print the letters.
ASTRONOMICAL PHOTOGRAPHY.
To the Editors of " Knowledge."
Sirs, — Would you be so kind as to give me some hints
about astronomical photography. I have an ordinary quarter-
plate hand-camera, and a 2i" refracting telescope. I should
be extremely grateful for any advice on the subject.
W. P. WILLIAMS.
Arlington Park College,
Chiswick.
In answer to the above letter, Mr. J. Milton Offord, F.R.M.S.,
has kindly sent the following note.
SIMPLE DIRECTIONS FOR PHOTOGRAPHY WITH
A SMALL TELESCOPE.— Photography of the Sun may be
taken with a very small telescope, using an enlarging lens in
place of the eyepiece and a screen close over the plate. The
exposures are so short that a fixed telescope will answer.
For the Moon use the fastest plates obtainable with an
enlarging lens. Exposures of about one second at full aperture
can be given and the amount of enlargement possible is
dependent on the aperture of the telescope. Images about
one-inch diameter with a two-inch telescope should show a
good deal of detail.
Planetary photography is beyond the reach of a small
telescope, except in the case of Venus, where the crescent
form can be photographed with an enlarging lens.
For stellar photographs use the telescope as a guide to an
ordinary camera firmly attached to it. With patience, good
photographs may be taken by keeping a bright star in the
centre of the field of the guiding telescope. This is best done
by bisecting the out-of-focus image of the star with cross wires
in the eyepiece. Even a simple pillar and claw stand may be
used, but it is essential to balance well the telescope and
secure a comfortable rest for the observer's head and arm.
The apparatus needed is quite simple: a light-tight
tapering box, securely fastened to the outside of the eye end
of the telescope leaving the rack tube free ; a focusing glass,
finely ground, with its centre rendered transparent by a
microscopic cover glass being cemented to it with Canada
balsam ; a plate-holder as light as possible ; a simple
magnifying glass in a screw mount for focusing, and a
dark card to cover the object-glass end of the telescope
will be required. The enlarging lens is important; it takes
the place of the ordinary eyepiece, and the best form is a
triple-cemented lens on Steinheil's principle, as used for
dissecting microscopes; cost about 10/-. This kind of lens
passes a great deal of light and gives sharp images.
To take a photograph, say, of the moon : First obtain the
actinic focus, if a refracting telescope, by trial. To do this
mark the draw-tube roughly in fractions of an inch, say for half
an inch, round the visual focus ; then make a number of
exposures at different focal lengths until the best result is
obtained. When this is found, the focusing lens can be adjusted
to view the moon through the central clear space in the ground
glass, and with the telescope at best actinic focus, made to give
good visual focus and fixed there, so that ever after when focusing
with this lens it will be the true focus for photography.
Having obtained the focus, cover the object glass with the cap.
Set the telescope in advance of the Moon and wait until the
Moon's image will be central, having the plate open, and then
expose by removing and replacing the card. It is best to have
the card larger than the aperture and hold it in front for a while
before exposing, to prevent shaking the telescope, quickly
moving it to one side and back again to expose.
For developers Metol Hydrokinone or Paramidophenol are
good. For plates, Imperial Flashlight or Lumiere Sigma
answer well ; they should, of course, be backed.
THE "FOURTH DIMENSION."
To the Editors of " Knowledge."
Sirs, — There is one statement in Mr. Redgrove's letter in
the June number of " Knowledge "to which I ought to reply
He says that he had " already intimated " that he did not
intend to discuss the question further with me. This is not
correct ; what he said does not bear this meaning. However,
I have no wish to continue the correspondence, and, since he
does not wish to reply to my letter in the April number of
" Knowledge," I am quite content that what is contained in
that letter should remain the final statement of the issue
between us. JOHN JOHNSTON.
Hendon, N.W.
THE PLANET MARS.
To the Editors of " Knowledge."
Sirs, — A copy of your Journal for May, 1913, has been sent
me, apparently to call my attention to, and perhaps secure my
comment upon, an article denying the reality of the canals of
Mars. Comment on the argument is unnecessary, but the
statement on the first page, that Schiaparelli is responsible for
the theory of their artificiality, should be corrected. The
blame for the discovery rests wholly on me. His theory was
that they were natural channels, though, with the magnanimity
and open-mindedness of genius, he wrote to me before his
death : " Votre theorie devient de plus en plus probable."
PERCIVAL LOWELL.
Lowell Observatory,
Flagstaff, A.T.
THE TRUE CAUSE OF SEA-SICKNESS.
By H. NORMAN BARNETT, F.R.C.S.
The questions "To what is sea-sickness really due ? "
" Is there any cure ? " have often presented them-
selves to the minds of the general public.
There is probably no ill which flesh is heir to that
has a more constant interest, especially in these days
of travel ; for it presents itself to the week-ender
crossing from Dover to Calais as well as the traveller
to the Far East or West.
There is no minor ailment — minor so far as its
pathology is concerned — which causes so much
discomfort, none which gains so little sympathy
from those unaffected by it, and has had such
divergent prescribing with so little good result.
There are many theories of the cause of sea-
sickness. I have had proof of the untrustworthi-
ness of most of them. What is known as the
" endolymph " theory is, however, scientificallv
accurate and supported by much practical evidence
of its truth.
Having once found a cause which is a satisfactory
explanation of the various phenomena of sea-sickness,
its prevention and even cure become a comparatively
simple matter ; for we have in the bromides drugs
which, when properly handled, are capable of good
results in the treatment of this disorder.
The sickness which occurs when crossing the
Channel or the Irish Sea, and vanishes when the boat
reaches its destination, is vastly different from that
arising in the Indian Ocean during the south-west
monsoon, when for a week the ship is violently
pitching, so that even seamen have difficulty in
remaining in their bunks at night. Supposing a
patient to be in delicate health, or suffering from
some concomitant ailment, the results may be most
serious.
I have met many cases where great prostration
had to be faced ; others where haemorrhage
threatened a phthisical patient. Many patients who
are often thoughtlessly ordered abroad for their
relief or cure may be reduced to a very serious
condition. I am glad to note a change in this
respect, but many are still sent on long sea voyages
who could be much better treated in a sanatorium at
home.
Sad cases are often seen of those in the second
and even third stages of phthisis who have been
enabled to take the voyage with much financial
difficulty, and have to make it as one of three
or four in a small third-class cabin. Such patients,
often unable to touch the food — good, but rather
coarse — are particularly bad subjects should the
ship encounter rough weather. They are usually
violently ill, and have to remain in lower-deck
cabins, with every porthole closed. The atmo-
sphere of such a cabin teems with tubercle bacilli
and other forms of germ life inimical to health.
The result is that the unfortunate patient lands, if
he survive, on some distant shore a piteous wreck,
friendless, probably almost penniless, in every way
worse than when he left England, having on the
journey probably caused infection to more than one
cabin-mate.
The only class of phthisical patient that should be
allowed to go for a long voyage on a passenger ship
is one in the first stage of the disease, who can afford
to have an entire first- or second-class cabin, with
plenty of air space, to himself. If bad weather be
met with, fair ventilation can then be secured. This
minimises the risk of sea-sickness for the patient,
and danger to others is avoided. A sea voyage is
very beneficial for those suffering from surgical
tuberculosis so long as the cases are not too
advanced.
I would designate sickness at sea as that which is
produced in a person whose digestive organs are at
fault in one way or another, and which is often
confounded with true sea-sickness. I feel sure that
all who give any thought to the matter will find
an explanation in this of cases which are evidently
not explicable on the theory to which I shall presently
refer. They are, in fact, cases of severe sick
headache which might occur anywhere.
The origin of sea-sickness is not so apparent as
many seem to think. That the exciting cause is the
motion produced by a ship on a rough sea is the
indefinite reason assigned, but it should be remem-
bered that there are many predisposing causes and
circumstances that modify the exciting one.
Predisposing Causes may be divided into those
connected with the stomach, those connected with
liver, those connected with the nervous system, and
those connected with the ship.
Those connected with the Stomach have had too
great stress laid upon them. In the healthy
individual symptoms referable to the stomach are
secondary, being the result, not the cause, of the
malady. In those who are suffering from gastric
disturbance, either chronic or acute, or who go on
board a ship with an overloaded organ, the condition
will prove a predisposing cause to " sickness at sea,"
or even to the true ailment, by rendering them more
liable to react when any abnormal condition of
things is experienced, such as the motion of the ship
if rough weather be encountered.
Those connected with the Liver we may dismiss
with a word, since what has been said above of the
stomach will apply equally to the liver. A sluggish
liver — one which is not secreting actively — is a very
bad companion for the sea-voyager, but it is not of
so much importance as a predisposing cause as one
253
Al
254
KNOWLEDGE.
July, 1913.
might think from reading the advice given by some
writers.
Those connected with the Nervous System are very
important. Nervous fear or association of ideas
will produce nausea without being on board a ship.
I know of one lady who has made several voyages to
India, on each occasion suffering much from sickness,
who dare not venture to a dock or wharf, as on
seeing the shipping violent nausea is produced.
Apart from such remarkable effects as this, nervous
anticipation of sickness or of danger from the sea
is a potent predisposing cause. Again, persons who
are generally neurasthenic, though without particular
reference to the sea, are usually bad subjects ; while
with those who have had brain injury or are liable to
epilepsy the sea will, as a rule, have an easy victory.
So inconsequent a thing as a nervous headache is a
predisposing cause of some importance. In fact,
any condition of the nervous system which is not
perfectly normal is liable to render the person under
it a prey to mal-de-mer.
Those connected with the Ship. The ship itself is
important, not only as an exciting, but also as a
predisposing cause. A ship which is a bad sea boat,
and takes heavy seas aboard, one in which the
vibration is great, or which has a marked list, often
induces sickness, when much worse weather with
more actual motion on a better sea boat will not do
so. This result is no doubt due to nervous influences
at work, such as apprehension of danger from the
noise of large quantities of water falling on the upper
decks, and many other sounds which are more
marked on a badly found ship than on a well-found
one.
The Exciting Cause is mainly the motion of the
craft on a rough sea. This motion is communicated
through a special sense to the brain, and thence to
the stomach as a secondarily affected organ. The
exciting cause, however, is not quite so simple as it
may appear at first sight. Thus we find that a
pitching motion produces sickness much more
quickly than a rolling one ; that a person accustomed
to the long, slow movements of a liner on great
oceans may easily succumb to the short motion of a
small ship in land-locked seas. It is found if one
lies down on going aboard, or when a storm is
blowing up, that sickness can often be averted ; and
also that if the weather becomes gradually worse
passengers can generally stand it who would
certainly be ill if they were subjected to a sudden
storm or went straight from dry land to a boat on
rough water.
It is, in my opinion, due to a complete misunder-
standing of the true cause of sea-sickness that so
few cases have been relieved and remedies of little
or no value have been prescribed. Most people
seem to have taken it for granted that, since
vomiting and nausea are prominent symptoms, the
disease is due to gastric disturbance. As well might
it be said that vomiting in the case of a tumour of
the brain is due directly to gastric trouble.
It will be well here to review the various theories
put forward before taking up that which I consider
to be the true cause.
There can be no doubt that symptoms of gastric
disturbance are the most prominent, and, to the
casual observer, or the scientific one who has not
seen a great deal of this complaint, they appear to
be the only ones. Those — and they are many — who
hold that such symptoms are primary maintain that
the motion produced by the ship creates a dis-
turbance of the stomach and its contents, which sets
up a feeling of nausea, followed in due course by
vomiting. It is not clear why a particular movement
should affect the mucous membrane of the stomach
in this way, or why the motion of pitching should
have a greater effect than that of rolling. Much
confusion would be avoided if it were remembered
by those who advance this theory that there are
many persons whose digestive organs are weak or
easily affected by any unusual condition. In these
cases, no doubt, sickness at sea is set up, and
stomachic medicines do good. To arrive at the
truth the exceptional must be eliminated and the
average insisted on ; otherwise cases could be found
to bear out apparently an}-, even the most extrava-
gant, theory.
The theory that while the gastric disturbance is
the primary one the brain has something to do with
the origin of the sickness, but rather as a predis-
posing than exciting element, is held by some.
Some hold that in a sluggish liver, which reacts
on the stomach, we have the true and only cause
which is responsible for sea-sickness. Such a view
leaves inexplicable many of the symptoms associated
with the condition.
The theory of imagination is advanced to show
that the primary nausea and the secondary vomiting
are figments of a diseased imagination, and if persons
so afflicted went on board ship determined not to be
sick they would probably not suffer. This savours
rather too strongly of Christian Science to be worthy
of consideration.
Zing is of opinion that sea-sickness is due to a
high degree of cerebral anaemia, induced by the
pitching of the ship, caused by some obscure action
of the vasomotor centres comparable to the mode of
action of the emotions. It is doubtful if the brain is
anaemic during sea-sickness ; the good effects of the
bromides point to the reverse. He also holds that
the stomach is not directly concerned in the act of
vomiting, which he considers Nature's method of
replenishing the depleted cerebral circulation. The
vasomotor centres are certainly disturbed, as evi-
denced by the flushing and subsequent chilliness
experienced in sea-sickness. The disturbance I
believe to be due to the emotion of fear, since
this and profound depression are symptoms of the
disorder. Such disturbances are but symptoms, and
by no means account for all phenomena of the
condition.
There are some who hold that it is through the
July, 1913.
KNOWLEDGE.
255
sense of sight that sea-sickness is produced, the
sight of the waves, the motion of the ship's masts,
and other objects seen at sea being conveyed through
the optic nerve to the brain. The effect of atropine
on some cases is pointed out as confirmatory evidence
of this theory
In considering the action of the sea upon special
senses, and through them upon the brain, we are
coming into the region of scientific reasoning and
leaving that of empiricism. It is, however, to
another special sense we must look for a true
explanation. There are some cases in which the
sense of sight plays an important part ; but there are
great difficulties in the way of accepting disturbance
of this sense as the cause in all cases, or, indeed, as
the true cause in any, the effect of atropine notwith-
standing. The cases benefited by this drug are those
in which physical fear is a prominent feature. The
temporary impairment of sight by atropine — a
bandage would have the same effect — calms the
nervous system by preventing the patient seeing
the motion of the water and the ship.
Thus it is a well-known fact, and one in my
own experience, that a traveller will be made ill
by observing the motion of a passing ship, who
does not become so by feeling that of the one on
which he is travelling. Nor does the optic nerve
theory explain the cases, with which all are familiar,
where the patient, having been asleep in fine weather,
or when the ship is in dock, wakes up violently sick
when the motion of a rough sea ensues.
It is to the organ which is closely allied to the
sense of hearing, which has to do with equilibrium
and the indication of the perpendicular position,-
that we must turn for a satisfactory explanation
of the many phenomena of sea-sickness.
It will be well, before proceeding to indicate
the way in which the effects are produced, to
review briefly the anatomy and physiology of the
part.
The internal ear is divided into the cochlea (or
special organ of hearing), the vestibule, and the
semicircular canals. It is the last that claim our
attention. These canals are hollowed out of the
petrous portion of the temporal bone : thev are
three in number, each one being placed at "right
angles to the other two. Each osseous canal
contains a membraneous one, the lining epithelium
of which secretes a fluid called endolymph.
The auditory nerve divides into two at the bottom
of the internal auditory meatus : the anterior branch
goes to the cochlea and special organ of hearing ;
the posterior is distributed to the semicircular
canals. We have between this nerve and the vagus
nerve a distinct connection by means of the facial
nerve, along which impulses can be conveyed to the
stomach from the semicircular canals.
In so far as the vomiting of sea-sickness is a reflex
act it is possible that the sympathetic nerve has also
something to do with the causation of sickness,
when the terminal branches of the posterior division
of the auditory nerve are irritated.
The anatomical direction of the canals themselves
should be remembered — i.e., two vertical and one
horizontal.
The semicircular canals have two functions:
(1) that directly connected with hearing, by collect-
ing in their fluid contents sonorous undulations from
the bones of the cranium ; (2) that indirectly
connected with the sense of hearing, by informing
us as to our equilibrium, by means of the constant
alterations in pressure of the fluid within the
canals.
This is closely associated with coordination of
muscular movements. It has been found that when
the horizontal canal is divided in a pigeon a constant
movement of the head from side to side occurs.
When one of the vertical canals is divided, up-and-
down movements are produced. These movements
are associated with loss of coordination, as after the
experiment the bird is unable to fly in a proper
manner.
Having regard to these anatomical and physio-
logical facts, and in view of the proofs derived from
observation of the signs and symptoms of sea-sick-
ness, there can be little doubt —
That the true cause of sea-sickness is irritation of
the terminal fibres of the auditory nerve dis-
tributed to the membranous labyrinth ;
That the irritation is conveyed, through the nerve
connections mentioned above, to the vagus,
and possibly to the sympathetic, and thence
to the walls of the stomach ;
That it is primarily an irritation of cranial nerves;
That this irritation is caused by the motion of a
ship on rough water, but not by this alone.
Any motion which is contrary to that usually
experienced by the fluid contained in the
semicircular canals will cause a set of
symptoms exactly similar to those of sea-
sickness.
Our semicircular canals constitute a sort of human
spirit-level. It is not difficult to conceive that any
motion which will more or less violently throw the
fluid against its containing walls, richly supplied
with delicate nerve-endings in direct communication
with brain and stomach, will produce symptoms
referable first to our equilibrium, then to the cere-
brum, and finally to the stomach. This is what
occurs in sea-sickness.
In searching for the true pathological cause of any
condition it is a usual and proper rule to find out
under what varying conditions similar symptoms are
produced. Such a survey has not been accorded to
sea-sickness. It was concluded that the person
affected was suffering from a sort of bilious attack,
produced by the unusual motion, combined, perhaps,
with the smell of oil, and so on, on a steamboat.
Such a lax way of viewing causation would have been
condemned in any other disease, but a good-humoured
laugh at the sufferer, combined with advice as to
256
KNOWLEDGE.
July, 1913.
diet and the ordering of a couple of pills, has more
or less satisfied a large proportion of the profession,
if not the public. It is strange that this should
be so, as the symptoms of an ordinary bilious
attack are not at all similar to those of well-
marked and true sea-sickness. Let us therefore try
to find if similar symptoms are produced under other
circumstances.
If the body be rotated rapidly, and an attempt be
then made to walk, it will be found that staggering
has been produced, clearly proving that coordination
has been interfered with. This is owing to the
endolymph having been subjected to unusual move-
ment. Nor. if rotation be continued, is incoordination
the only symptom : headache, giddiness, slight double-
sight, rapid pulse, flushing followed by chilliness, and
distinct nausea will in turn be experienced — these
being produced by the irritated endings of the
auditory nerve conveying sensation to brain and
stomach. If we compare the above set of symptoms
with those of sea-sickness a marked similarity is
at once seen.
It is a well-known fact that some children are
unable to use a swing owing to nausea, giddiness
and headache being caused, while other children
and many adults suffer in a minor degree. Here,
again, the endolymph is subjected to an unusual
motion as compared to that caused by our ordinary-
movements.
There are also those who experience when on a
switchback railway or a water-chute one or more of
the above symptoms, undoubtedly due to a similar
cause.
The high dive and violent horseback exercise have
been known to produce in those unused to such
sports disagreeable effects of a nature akin to those
of mal-de-mer.
In my own personal experience, and that of most
other sufferers, it is the pitching motion that pro-
duces the most severe form of sea-sickness. In
a rolling ship the nausea and vomiting are much
less and of shorter duration. Have we in this fact
any proof of the endolymph theory ? Undoubtedly ;
since it is the fluid in the vertical canals that is
affected in pitching, and, as they are two to one, we
naturally suspect double the effect. In rolling, on
the contrary, the fluid in two canals is practically at
rest, only one — the horizontal — having its fluid level
and pressure on its walls much changed.
The proportion of those who do not overcome
sea-sickness, if long on board ship at one time, is
small ; usually, after a more or less prolonged
apprenticeship, the nerve filaments become accus-
tomed to the motion. If, however, the ocean be
exchanged for the sea or channel, where the waves
are short, and the liner of twelve thousand or more
tons replaced by the boat of eight hundred tons,
sickness in many cases will return, even in the case
of old seamen.
Such a fact cannot, I think, be explained on any
other hypothesis of the causation of the malady
than the endolymph theory; accept that, and the
explanation is easy. The fluid, which has become
accustomed to one motion, is subjected to another of
a different character, and the new one produces its
effect. Should the circumstances be reversed and
the large ship substituted for the small one, sickness
will not, as a rule, be produced ; since the motion of
the former is better borne, the endolymph being
more agitated by short seas on a small boat. A
person who suffers under these conditions is not
necessarily a bad ocean traveller.
Seasickness produced during sleep is a stumbling-
block to those who believe that the optic nerve is the
medium for sensation producing sickness, and is
difficult to explain by any process of reasoning but
the one. The endolymph is, of course, influenced
by motion whether the person is awake or asleep ;
the effect, however, is considerably lessened by the
recumbent position. Hence it is a wise precaution,
advocated by many who do not grasp the true
reason, for a person liable to mal-de-mer to lie down
when starting on a short passage. Such advice is
obviously not of much use to those starting on a
long sea voyage, with continued bad weather, unless
supplemented by treatment.
Some persons after a short voyage, on which they
have experienced bad weather, continue to feel the
motion after landing. This is a very direct proof
of the origin of the sensations felt on board ship, the
explanation being that the fluid in the canals has
accustomed the nerves to the feeling of the motion,
which they do not lose for some time.
It is found that, however ill a person may be, the
moment the ship runs into perfectly calm water all
symptoms vanish, except perhaps the sensation just
referred to. Such would not be the case were the
stomach seriously at fault, but is explained by the
action of our " spirit-level."
It is a curious fact that, in these days of scientific
accuracy, the bromides are sometimes prescribed by
those who speak and write of sea-sickness being of
gastric or hepatic origin. I can see only one legiti-
mate reason for prescribing bromides — namely, belief
in the nervous origin of the ailment — and I would
point out, as a further proof of the pathology
advanced above, the very direct effect they have
in subduing symptoms.
I am not aware that such weight of practical and
scientific proof can be brought forward in support of
any other theory of the pathology of sea-sickness.
The endolymph causation, indeed, can hardly be
regarded as theory ; the evidence of its being the
true cause is, short of ocular demonstration, to my
mind complete. Gastric symptoms are certainly
prominent, but not more so than in many con-
ditions where they are admittedly secondary. The
symptoms referable to the semicircular canals and
the brain are so evident that there is no mistaking
them, though, to a great extent, they have been
ignored in the past.
THE SUBLIMINAL SELF.
By J. ARTHUR HILL.
I.
There has probably always been a suspicion,
among thinkers, that we are greater than we seem
to be. For one thing, the idea flatters our natural
vanity — or, to put it more mercifully, our hopes
and longings and aspirations — and is a hospitable
refuge, giving ampler air and spaciousness in times
of suffering, due to our limitations. It is expressed
in many forms and places. In the Bible, mortals
are referred to as" gods " (Psalm lxxxii, John x); in
Christian theology the Divine and human natures are
united, not in one unique instance, but in all (e.g.,
Dante, near the end of the " Paradise " and else-
where) ; in Plato's " Republic " the human soul
descends from supernal realms, drinks of Lethe, and
forgets its previous experience (limits itself, puts off
its greatness, takes on the form of a servant) ; and
this kenosis is closely paralleled in some of the
teachings of Hinduism. The standard modern
expression of the idea is that of Wordsworth in the
"Ode":—
Our birth is but a sleep and a forgetting !
The Soul that rises with us, our life's Star,
Hath had elsewhere its setting,
And cometh from afar :
Not in entire forgetfulness
And not in utter nakedness,
But trailing clouds of glory do we come
From God, who is our home.
And elsewhere, in a sonnet, he finishes with the often -
quoted line : " We feel that we are greater than we
know."
Until recently these ideas were left to the domain
of the speculative philosopher, or poet, or prophet.
But within the last quarter of a century or so they
have more and more claimed the attention of the
scientific man, and they have more and more
obtained the support of actual, scientifically observed
facts.
II.
If there is something mental or psychical in us
beyond the bounds of our own minds or souls as we
know them in self-consciousness, how are we to
discover this something; how become aware of it ?
The answer cites various classes of fact, and the
inferences to be drawn from them.
(1) Subliminal Sensation. — One small fly walking
over the back of my hand arouses no sensation. It
is not felt. But if there were six flies instead of one
I should feel them. Thus, six times nothing
produces something ; or, to put it the other way, a
given amount of sensation is produced by a certain
stimulus, but when the latter is decreased by five-
sixths the remaining sensation is not one-sixth of
the original sensation, but, on the contrary, is nil.
In other words, there is a " threshold " ; below this
threshold of intensity a stimulus produces no con-
scious sensation ; but we suppose that it produces
a subconscious or subliminal one. Something in us
perceives the one fly, even if the normal mind does
not. This is borne out by various experiments in
hypnosis, whereby the subliminal can be put — as
Professor James used to say — " on tap." Conscious-
ness is like a spectrum-band. There are sensations
which we do not normally become aware of, as there
are rays of light which we cannot see.
(2) Subliminal Intellection. — For this the evidence
is ample. There is no doubt whatever that some-
thing in us thinks, reasons and calculates without
the normal consciousness knowing anything about
it. The most striking experiments on this point are
those of Dr. J. Milne Bramwell, who ordered
hypnotised patients to carry out some action after
their arousal from the trance — as, for example, to
make a cross on a piece of paper at the end of a
specified period of time, reckoning from the moment
of waking. In the normal, waking state, the patient
knew nothing of the order; but a subliminal mental
stratum knew, and watched the time, making the
patient carry out the order when it fell due. The
period varied from a few minutes to several months.
For instance, Dr. Bramwell would say to the
hypnotised patient : " You will feel impelled to
make a cross on a piece of paper, and will do so,
putting down the time also. This is to take place
at the expiration of 24 hours and 2,880 minutes."
This is one of the actual cases : the order was given
at 3.45 p.m. on Saturday, December 18th, and it
was carried out correctly at 3.45 p.m., December 21st.
In other experiments the periods given were 4,417,
8,650, 8,680, 8,700, 11,470, 10,070 minutes. All
were carried out correctly. In the waking state the
patient was quite incapable — as most of us would
be — of calculating mentally when these times would
elapse. But the hypnotic stratum could do it, and
could ensure that the order should be carried out at
the exact moment of falling due. In one instance
the time happened to expire during the night. The
patient made the cross on paper at her bedside at
the correct time, apparently without waking, for she
had no recollection of having done it.*
We may say, then, that not only is there some
subliminal part of our minds that can calculate, but
also that this something can calculate better than
the ordinary waking consciousness.
The same conclusion is arrived at by consideration
of the performances of "arithmetical prodigies." It
* Proceedings, Society for Psychical Research, XII., p. 185.
257
258
KNOWLEDGE.
July, 1913.
is often found that these curiously endowed people
can solve in a few seconds — and sometimes almost
instantaneously — problems which would utterly
baffle most ordinarily educated people, and which
would take an average arithmetician a quarter of an
hour's rapid work with pencil and paper. Yet these
prodigies — who, by the way, are often, like Dase,
Buxton and Mondeux, of very low mental power so
far as their normal faculties are concerned — are
entirely unable to tell how they do it. They do
not consciously work the sum out. They let it
sink into their minds and then wait for the answer
to be shot up. It is like putting the plum-pudding
into the geyser to be boiled ; or like putting the pig
into the Chicago machine. It goes in pig and
comes out sausages. The intermediate processes
are hidden from us. The calculation is made
subliminally — below the threshold of ordinary
consciousness.
Subliminal Memory. — The results of hypnotic
experiment and of the study of pathological cases
of split personality (such as Dr. Morton Prince's
Miss Beauchamp) are sufficient to prove beyond
question that the subliminal memory is wider than
the normal one. Many things which we " forget "
seem to slip down below the threshold, thus
becoming lost to ordinary consciousness, but
remaining accessible by hypnotic methods. Or it
sometimes happens that they are recovered in sleep,
when the conscious self is in abeyance, and the
other strata of the mind come to the top. Or they
turn up in automatic writing with planchette or a
pencil. In a recent striking case, reported to the
Society for Psychical Research, an automatic writer
had communications from a " spirit," who called
herself Blanche Poynings, and gave a great deal of
historical detail which the automatist did not con-
sciously know. But it was afterwards found that
Blanche Poynings was a character in a novel which
the automatist had had read to her many years
before, and the novel contained all the historical
details given. All this had been " forgotten." It
had slipped down below the threshold. But the
subliminal strata still retained it and could produce
it (in the usual mystifying spirit style) when tapped
by a borehole, sunk, so to speak, through the
upper level of consciousness, by means of automatic
writing.
Subliminal Emotion. — This is a reality also,
though perhaps less provable. An interesting
example of the necessary evidence occurred in
Mrs. Verrall's experience with automatic writing
some time ago. [Mrs. Verrall is a classical lecturer
at Cambridge ; translator of " Pausanias " ; widow
of Dr. A. W. Verrall, late King Edward Seventh
Professor of English Literature.] This automatist,
without experiencing conscious emotion, found the
tears running down her face when she roused herself
from a semi-conscious state in which she had been
writing automatically. The script, on examination,
turned out to contain references to two friends who
had died under tragic circumstances ; but Mrs.
Verrall was quite unaware of the contents of the
script until she had read it. Evidently some part
of the mind was not only thinking and remembering
and making the fingers write without conscious
direction, but was also feeling and suffering, and
making the eyes overflow without the conscious
mind knowing why. (Proceedings S. P. R., XX., p. 15.)
Subliminal Creation. — This is the best proved of
all, for most of us prove it for ourselves every
night. In dreams every one of us becomes novelist
or dramatist, inventing situations — usually absurd
to the waking mind — which are absolutely novel in
our experience. And, to step at once to the higher
plane, it can be said, without fear of contradiction,
that all works of genius, all creations, are uprushes
from subliminal depths. They are not produced by
taking thought. The process is felt to be quite
different from that of the faculty which thinks and
reasons consciously. It is more a waiting than a
working. " All is as if given," said Goethe. (Alles
ist als ivie geschenkt.) The inspiration comes from
below the threshold. Many great writers amply
bear out Goethe's dictum. Ibsen wrote " Brand "
in three weeks in a state of feverish exaltation,
scrambling out of bed to write down, half asleep,
the lines which rose tumultuously to the surface of
his mind. Charlotte Bronte could write freely on
some days, while at other times the story hung fire
for weeks at a time, refusing to unroll itself ; then a
volcanic burst, and she would write furiously until
she was ill with the strain. In her preface to
Emily's " Wuthering Heights," discussing the Tight-
ness of creating such characters as Heathcliff, she
states the case in unsurpassed language : —
" But this I know ; the writer who possesses the creative
gift owns something of which he is not always master — some-
thing that, at times, strangely wills and works for itself. He
may lay down rules and devise principles, and to rules and
principles it will perhaps for years lie in subjection ; and then,
haply without any warning of revolt, there comes a time when
it will no longer consent to ' harrow the valleys, or be bound
with a band in the furrow ' — when it ' laughs at the multitude
of the city, and regards not the crying of the driver '—when,
refusing absolutely to make ropes out of sea-sand any longer,
it sets to work on statue-hewing, and you have a Pluto or a
Jove, a Tisiphone or a Psyche, a Mermaid or a Madonna, as
Fate or Inspiration direct. Be the work grim or glorious,
dread or divine, you have little choice left but quiescent
adoption. As for you — the nominal artist — your share in it
has been to work passively under dictates you neither
delivered nor could question — that would not be uttered at
your prayer, nor suppressed nor changed at your caprice. If
the result be attractive, the World will praise you, who little
deserve praise ; if it be repulsive, the same World will blame
you, who almost as little deserve blame."
This would be endorsed by Scott, who dictated
" The Bride of Lammermoor " while ill and in an
abnormal mental state, and found a great part of the
story quite new to him when he read it in the book.
Also by Stevenson, who tells us that he wrote
fifteen chapters of " Treasure Island " in fifteen
days, then stuck completely ; " my mouth was
empty ; there was not one word of ' Treasure Island '
in my bosom " ; but again the tide rose, " and
July, 1913.
KNOWLEDGE.
259
behold ! it flowed from me like small talk," and he
finished it at the rate of a chapter a day. It is
interesting to remember, in this connection, that
Stevenson used to dream most of his plots, as he
describes in " Across the Plains."
Similar statements of experience could be culled
from other fields of creative art. Perhaps it is even
more marked in music than in literature Mozart,
for example, had a vivid perception of the extraneous
nature of the afflatus — extraneous, that is, to the
conscious mind ; and, among painters, Watteau
frankly and quaintly avows himself puzzled at the
" queer trick he possesses," evidently not knowing
in the least how he did it. Indeed, no genius does
know " how he does it." If he knew, he could teach
others to do it also. No, it is not the knowing part
of the mind that is the agent, nor is it any part that
the consciousness can understand. The power lies
deep buried in the subliminal levels. It is only its
results — its exfoliations — that we see.
It is established, then, that there can be mental
or psychic activity of many kinds — sensational,
intellectual, reminiscent, emotional, creative — over
and above anything that the conscious mind is
aware of. Science has proved that we are greater
than we knew. The hinter horizons of the mind
have receded and fled away. New vistas open out
in metaphysical psychology. The soul is become
immense, immeasurable. We are suddenly trans-
planted from a cellar dwelling to the illimitable
prairie. Not only do we not know what we shall
be, but we do not even know what we are. Like
Malvolio, therefore, we may again "think nobly of
the soul." The Psalmist, quoted approvingly by
Jesus, said : " Ye are gods." A blinding and stunning
thought ! But, whether we go so far as that or not —
and, after all, it is not a very great thing to say, for
we are certainly more wonderful creatures than many
of the Greek and Norse gods — we can at least
subscribe to that profoundly wise and suggestive
triplet of Emerson's, who in so many of these
things had a curiously prophetic instinct: —
Draw, if thou canst, the mystic line,
Severing rightly his from thine,
Which is human, which divine.
III.
The late Professor William James used to say that
he thought the most fundamental problem in
philosophy was that of the One and the Many.
How can a Universe which is Whole and One,
containing everything that is, both material and
immaterial — how can this One Thing be at the
same time Many ? And if we start with the many-
ness, this and that tree and house and mountain and
country, this and that microbe, blade of grass,
butterfly, how are we ever going to visualise them
as one, when they are so incontestably disparate ?
The problem is at present insoluble. We can begin
at either end, but there is no meeting-place in the
middle. One remains One, and Many remains
Many.
But in the region of mind or soul the modern
doctrine of the subliminal self — which, first pro-
pounded by Myers twenty-five years ago, was after-
wards hailed by James as the greatest modern
advance in psychology, and which is continually
being buttressed by new facts — is at least pointing
to a kind of solution to this problem. Human
minds are many, it is true ; but they are closely
alike, and in all biological science it is found that
close similarity points to a common source. In some
sort, then, it is to be surmised that all human minds
descend from a common source. But the pheno-
mena of psychical research — telepathy, to name only
one — indicate that there is absolute connection
between the minds here and now existing, in ways
over and beyond those accounted for by the known
senses. And there is reason to believe, though the
evidence is too complex to specify here, that in
telepathy and allied phenomena it is the subliminal
part of the mind that is active. These and other
considerations point to the supposition that though
our ordinary normal consciousnesses are severed
from each other, and apparently distinct, so that we
have to communicate with each other by the clumsy
means of speech and writing, we are nevertheless all
in connection with each other in the subliminal levels.
To vary the metaphor, each of us is like a stream of
water issuing from one of the thousands of taps in a
city, but the water is the same, coming from the
same reservoir. The same soul thinks in all of us.
The One is the Many.
It may be said that this conclusion is a specu-
lative and abstract proposition. On the contrary, it
is extremely practical ; for it has close connection
with human action. Remember how we feel about
our brothers and sisters ; how we stand shoulder to
shoulder with them, feeling that the interest of the
family is a common interest, for which each indi-
vidual is bound to fight. Remember also how, broadly
speaking, the individual's welfare is bound up with
that of the family, and what is good for it, is also
good for its component units. And now think what
would happen if all men, or even all civilised and
educated men, could regard humanity at large as one
huge family, one in interest and, further, one in
reality and essence, being joined together in that
subliminal region, the individual separation of the
conscious minds being illusion, due to ignorance of
our real nature. Would not a revolution be effected?
I am sure it would. And, sooner or later, it will.
The religious doctrine of the brotherhood of man
was a noble moral inspiration but its appeal was to
the affective side, and it was consequently inopera-
tive against the coldly intellectual. But it is now
supported by science. Knowledge now goes hand in
hand with faith and love. A new dawn begins to
send up its shafts of light in the East. A new era
is at hand.
According to present conventions, it is bad form
to be in earnest about anything ; the proper thing is
to cultivate a manner of light banter which shall
give an impression of cleverness and wit. The
260
KNOWLEDGE.
July, 1913.
popularity of the fashion is very comprehensible ;
for there are always plenty of people who wish to
seem clever but are not. And the trick of it is
easily acquired. Be cynical and flippant about
everything, and you will get the credit of having
seen through the illusions of the world, and of being
a deeply wise man who conceals his wisdom. But
it is a pose and an affectation. There is really no
disgrace about being serious, at least occasionally,
nor in being honest, even almost habitually ! If I
seem too solemn or too enthusiastic in my vision of
the future when the unity of mankind shall be more
fully realised, I appeal from the decadent trifler of to-
day to the vigorous thinker of to-morrow — from Philip
drunk with sophistication and selfishness to Philip
sober with clear eyes and better ideals. Better times
are coming. We are beginning to see that we are not a
" concourse of warring atoms," but a vast multitude
of units which fit together and make up an organism ;
and that what is good or bad for the organism is
good or bad for the units. Solidarity and homo-
geneousness are the watchwords. Individualism
has been over-accentuated. We must see
humanity steadily, and see it whole — a whole,
however, within a still larger Whole of the entire
Cosmos.
SOLAR DISTURBANCES DURING MAY, 1913
By FRANK C. DENNETT.
May has been remarkable for the small amount of disturbance
upon the Sun. The disc has been examined every day, but on
twelve occasions (1, 3, 6, 8, 12, 13, 19, 20, 22, 23, 29, and 31)
it has appeared to be quite free from disturbance, bright or
dark. Short-lived pores were noted on three (11, 16, and 25),
and faculae on the remaining sixteen. The longitude of the
central meridian at noon on May 1st was 224° 27'.
On May 1st and 2nd the granulation of the photosphere
was noted as being very fine all over the disc. On the 11th
there appeared to be very many minute pores in the central
portion of the disc and in northern latitudes. One showed as
a small irregular umbra near the central meridian (94°) with
large faculic flecks about it.
On the 16th, in the afternoon, pores showed in high
latitudes both north and south, well to the west of the central
meridian, which was 24°.
On the 25th, at 5.15 p.m., in high latitude south-east, about
six days on the disc a small pore showed in a rough-looking
area, nearing the central meridian, which was 264° 13'.
Unfortunately no measures were made in either of these cases.
The faculic display was also of a most meagre description.
On the 4th and 5th a faculic cloud was measured at longitude
244°, south latitude 40c. On the 14th and 15th a small
bright facula was situated at 339°, 68° South ; on the 16th
and 17th a small facula at 312°, 10° North, and on the 17th, a
paler one at 310°, 12° South; on the 24th a pale one at
218°, 33° South, and another at 208°, 21° North. Perhaps
the most interesting one was a brilliant granule, less than
7° from the South Pole, seen on the 26th, 27th, 30th, and
June 4th.
Other faculae were seen, but not measured, near the
western limb on the 21st and 28th; south-western on the
7th, 10th, 17th, 18th, and 30th; south-eastern on the 10th,
14th, 15th, 17th, and 25th; and north-eastern on the 2nd,
9th, and 10th.
The Chart was constructed from the observations of
Messrs. John McHarg, A. A. Buss, C. Frooms, E. E. Peacock,
and the writer.
DAY OF MAY, 1913.
?
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THE MOON.
The plate of the Moon given in Figure 267, on page 261, shows much fine detail, particularly in the Maria Imbrium, Nubium and
Crisium ; Tycho, Copernicus, Kepler and Aristarchus are very well defined. From the sketch-maps published in " Knowledge "
during 1909 all the points to be seen in this plate may be identified. The image is shown as it would appear in an inverting
telescope. The photograph was taken at Paris on November 13th, 1902, at 2.57 a.m., with the Equatorial Coude. The
aperture was 23-62-ins., the focal length 59' 6" -6, and the exposure 0-6 of a second.
July, 1911
KNOWLEDGE.
261
Fiom a photograph
by P. Puiisux
FIGURE 267. The Moon. Age thirteen days live and a half hours.
262
KNOWLEDGE.
July, 1913.
Figure 268. Figure 269.
Photographed from Store Korsnes. Photographed from Bossekop.
Aurora Band across the Great Bear, March 29th, 1913, 10h 15™.
Fro/n a photograph
Figure 270. Nebula 9 Ophiuchi.
Taken at the Mount Wilson Observatory April 5th, 1905, with an exposure of 4h 30n
Position of the Nebula R.A. 16h 20m. Declination -23°.
by E. E. Ba) nard.
ON AN AURORAL EXPEDITION TO BOSSEKOF
IN THE SPRING OF 1913.
By PROFESSOR CARL STORMER,
(University of Christiania).
The following is a short account of a new auroral
expedition which I made to Bossekop in the spring
of 1915 for the purpose of completing the results of
my expedition to the same place in 1910.*
My assistant was the meteorologist, Bernt Johannes
Birkeland, who also went with me in 1910, and is
going with Roald Amundsen's expedition over the
North Polar basin.
The purpose of the expedition was mainly to
obtain more accurate and a greater number of
auroral photographs for the determination of the
form of aurora and its height and situation in
space, and, further, to experiment with prism-
objective photographing and the taking of cinemato-
graph films.
Our preparations and equipment were, on the
whole, the same as in 1910 ; but the following
improvements, based upon experience gained on
that expedition, were carried out.
The cameras were furnished with an arrangement
whereby a photograph of an illuminated watch-face
was taken on the plate simultaneously with the
aurora. The time could then be read from the
photograph, and also the exposure by the sector
described by the second hand. This improvement
I had already employed in photographing aurora in
Christiania in the winter of 1910-11.
In order to avoid the waste of time in changing
plates in a dark room, each station, in addition to
forty cassettes, was furnished with changing boxes
in which the plates could be changed in the open
air. Thanks to this improvement, it was possible
on some evenings to take more than eighty simul-
taneous photographs at the two stations.
In order to have the arms at liberty the following
improvement in the telephone arrangement was
made. The microphone and receiver were fixed to
the chest and head and connected with the field
telephone apparatus by a cord four metres in length.
In this way it became possible to utilise more
fully the brief moments during which the aurora
displayed its greatest intensity.
F"or the purpose of obtaining reliable parallaxes a
base of twenty-seven and a half kilometres was
chosen, as against four and a half kilometres in 1910.
The station at which Birkeland took up his quarters
was Store Korsnes, the other was Bossekop. As
assistant at Bossekop I had engaged Sergeant Ottem.
The direction from Bossekop to Korsnes was almost
due north.
Through the courtesy of the Telegraph Depart-
ment the State telephone line from Bossekop to
Korsnes was placed at our disposal every night
from 7.30 p.m.
Thanks to these arrangements, we succeeded in
one month in taking the following pairs of simul-
taneous auroral photographs at Bossekop and
Korsnes : —
Day.
Number of
Pairs taken.
Of these
Successful.
Feb. 28
Mar. 3
,, 4
„ 6
„ 11
„ H
„ 15
„ 16
„ 17
„ 18
„ 21
„ 22
„ 23
„ 24
„ 28
„ 29
„ 30
April 1
14
38
23
7
86
81
81
8
14
5
23
20
1
6
5
83
71
70
0
19
9
1
58
54
72
2
7
5
20
12
1
6
3
64
62
52
Total
636
447
On the six best evenings, the 11th, 14th, 15th,
29th, and 30th March and 1st April, the weather was
clear and the aurora vivid and continuous, so that we
were able to make use of every chance.
The parallaxes, thanks to the large base, were very
distinct, as a rule between five and fifteen degrees,
and the large number of photographs — four hundred
and forty-seven pairs as against forty-four in 1910 —
gives very much more certain and complete results
than on that occasion. If we reckon about ten
measurements to each photograph, these will give
more than four thousand reliable determinations of
height. All important forms of aurora were photo-
graphed, and there are long series of developments.
:'See Bericht iibcr cine Expedition nach Bossekop zwecks photographisclie Aufnahmen unci Hbheninessuitjieti von
Nordlichtem, mit 57 Figuren itn Text und 88 Tafcln. Videnskabsselskabets Skrifter, MathNaturv. Klasse 1911,
No. 17, Christiania.
263
264
KNOWLEDGE.
July, 1913.
A pair of the photographs are reproduced in
Figures 268 and 269 enlarged about two and a quarter
times, one degree answering to two millimetres in
the photographs. The time is Central European
time and reckoned from 0h to 24h, 0h answering to
12 noon.
With a prism-objective we succeeded in taking
some photographs simultaneously with the auroral
photographs, on which are seen stellar spectra and
some views of the aurora lying side by side,
answering to various spectral lines. The prism had
an angle of 60°+ and was placed in front of the
kinostigmatic objective, on the principle already
mentioned in my " Bericht." A systematic
employment of this method will be of great
importance to the study of the highest strata of the
atmosphere.
Most of the cinematograph attempts were failures,
as the film (Lumiere) was not as a rule affected by
an exposure of less than two seconds. It was only
with very intense aurora that we succeeded in
getting good photographs with an exposure of about
one second and with about two seconds' interval
between the photographs. Two or three such
series were taken, thus proving the utility of the
cinematograph both for taking photographs and for
registering rapid changes.
The working-up of the matter collected during
the expedition will be the subject of a subsequent
detailed account.
t With regard to the kind of glass that would be best for the purpose. I received valuable information from Dr. Slipher
when visiting the Flagstaff Observatory in the summer of 1912.
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
PROLONGED OBSERVATIONS OF TEMPORARY
STARS. — Professor Barnard has put the Yerkes 40-inch
refractor to a very useful piece of work in following the
temporary stars of recent years long after they have become
invisible to ordinary telescopes. He notes that in at least two
cases — T Coronae of 1866 and Nova Geminorum (2) of 1912 —
the Nova was identical with a previously seen or photographed
star. His study was made partly in the hope that he might
find some peculiarity in the aspect of faded Novae. In this
he was disappointed : a few of them show longer focus than
ordinary stars, and the more recent ones show slight variability,
but otherwise they are indistinguishable from ordinary stars.
T Coronae was a B.D. star of magnitude 9-5 before the out-
burst, and is now at practically the same magnitude and
apparently colourless.
Nova Cygni of 1876 is now of magnitude 15, perhaps
slightly variable : its appearance is hazy and the focus longer
than usual. In these respects it resembles Nova Aurigae of
1891, which is a magnitude brighter, and Nova Sagittarii of
1898, which is of magnitude 15.
Nova Persei of 1901 is now of magnitude 12$, well defined
and colourless, of ordinary focus. According to Professor
E. C. Pickering this star existed before the outburst as a star,
photographed as far back as 1890, whose light fluctuated
between magnitudes 13 and 14.
Nova Lacertae of 1910 also existed before the outbreak as
a star of magnitude 13$ ; it is now of magnitude 12$, having
the appearance of a small bluish-white nebula ; focus five
millimetres greater than usual.
Nova Geminorum of 1912 existed before the outbreak as a
13-5 magnitude star. It fluctuated in brightness last winter,
and was of magnitude 8? last January. On February 8th,
1913, "with good seeing and at the proper focus, the Ha
image was clearly seen. It was small, sharp, and intensely
crimson, surrounded by a greenish - blue halo 3" or 4" in
diameter. The normal focus, however, was not different from
that of an ordinary star."
Nova Geminorum of 1903 is now of magnitude 16$ and still
fading. The Nova of the Andromeda nebula (1885) is now
invisible; this may be partly from the bright background.
Professor Barnard also gives a diagram of the small stars
in the region of Tycho's Cassiopeia Nova of 1572. There are
several stars shown, but none of them appeared in any way
peculiar.
SATURN'S NINTH SATELLITE.— Another interesting
paper of Professor Barnard's describes his visual observations
of Phoebe with the 40-inch. Now that Saturn is far north
of the Equator he finds the satellite quite an easy object, at
least as bright as magnitude 14 (it had previously been
supposed to be of magnitude 16). The positions were in
practically perfect agreement with the American ephemeris,
which uses Dr. F. E. Ross's elements. As these were pre-
pared several years ago, and as the perturbations are very large,
this agreement is most creditable to him.
PARALLAX OF THE ANDROMEDA NEBULA.— Astr.
Nachr. No. 4650 contains a determination of the parallax of
one of the small companion nebulae of the great one, made by
M. Gustaf Strbmberg at Stockholm. He obtains for the
parallax 0"-073 with a probable error of 0"'055. Some
previous determinations had given 0" ■ 171, 0"-132, and
0" -070 for the parallax. As the nebula is a difficult object
for precise measurement it can only be claimed that the
results give some slight probability to the conclusion that it
has a sensible parallax, which of course if proved would
negative the idea of its being an external universe.
THE STAR POLARISSIMA.— Astr. Naehr. No. .4650
has an article by L. Courvoisier on this faint star, which is of
magnitude 9-3. It is only 10' from the North Pole, and thus
is always within the range of the field of view of a meridian
instrument ; also it is bright enough to observe on a clear
night with a partially illuminated field, so the writer suggests
that it might with advantage be used for obtaining the
azimuth error of the instrument. For this purpose an
accurate knowledge of its place and proper motion is
required. These are investigated in the article. The proper
motion is given as about 3" per century with a probable error
of one-third of itself. The star's right ascension this year
is 14h 12™, diminishing 5" each year.
VARIATION IN THE SUN'S RADIATION.— Astr.
Nachr. No. 4656 contains a paper by Messrs. Abbot, Fowle
and Aldrich on the simultaneous measures of the Sun's
radiation at Mt. Wilson and at Bassour, Algeria. The mean
value after correcting for atmospheric absorption, and so on, is
I -929 calories per square centimetre per minute. It appears
to increase 0-07 calorie for an increase of 100 in Wolfer's
sun-spot numbers. There is also an irregular variation of
II per cent, which is concluded to be really in the Sun, from
July, 1913.
KNOWLEDGE.
265
the fact that the two very distant stations agree in the days
that give unusually high or low values.
High radiation values are accompanied by a relative
increase in the strength of the violet radiations, and conse-
quently increased contrast between the centre and edge of the
Sun's disc. From this they conclude that the variation is
actually in the Sun, and not due to the interposition of a
meteoric screen. Haze was very prevalent in 1912 : it is
supposed to have been caused by the presence of fine dust in
the air, from the eruption of Mt. Katmai in Alaska. When
this is allowed for, the radiation of 1912 is higher than that of
1911. Hence the cause of the abnormally hot summer of
1911 is to be sought on the Earth, not in the Sun; but the
Katmai dust may have had something to do with the cold
summer of 1912.
BELTS ON NEPTUNE. — The same number contains a
series of drawings of Neptune made by Professor T. J. J. See
in 1899. They clearly show a number of curved dark belts on
each side of the Equator, where there is a narrow bright
streak. These drawings were made before the position of the
Equator had been deduced from the shift of the node of the
satellite's orbit, and it is interesting to note that the Equator
in the drawings is not in the plane of the satellite's orbit, but
inclined to it about 20°, which agrees with theory. Belts on
Uranus were seen by Mr. Buffham, Professors Young and
Schiaparelli and the Henry brothers. The four giant planets
seem to be all alike in this respect, as in low density and rapid
rotation.
THE SELENIUM PHOTOMETER.— A posthumous
paper by Professor Ristenpart describes an application of
the selenium photometer to the measurement of the diminu-
tion of light in the solar eclipse of last October. The time of
minimum light is very sharply defined, the curve on each side
being very steep ; while this particular research is more orna-
mental than useful, it illustrates the power of the method,
which depends on the increased electrical conductivity of
selenium when light falls upon it.
SCHAUMASSE'S COMET.— The following are improved
elements of this comet : —
Perihelion passage, 1913. May 15-1648, Paris M.T., Omega
53° 2' 17", Node 315° 5' 25", Inclination 152° 21' 23",
Log Perihelion Distance 0-163514.
Ephemeris for midnight, July 3, R.A. 13" 0m 12s, N.Dec. 28° 34' ;
July 7, R.A. 12h 52m 7s, N.Dec. 26° 56'; July 11,
R.A. 12h 45"' 508, N.Dec. 25° 29' ; July 15, R.A. 12h 41m 0s,
N.Dec. 24° 11'.
NAMES FOR THE units of planetary and stellar distances
are suggested by Mr. J. W. Scholes. He gives Parxsecarc for the
stellar unit. This is like the " Parsec " suggested by Professor
Turner. " Disethsun " is suggested for the distance Earth-
Sun ; for myself I should have thought the term " Astron "
very suitable for this, if not used for the stellar unit. For it is
an obvious abbreviation of Astronomical unit of length, which
has hitherto been the term used.
CONGRATULATIONS to Sir J. D. McClure on his
knighthood. There must be many of our readers who have
heard his lectures on astronomy, which were prepared with the
most conscientious care and zeal for accuracy, and whose
illustrations, both pictorial and verbal, were calculated to
arrest and sustain the interest of his hearers.
OBITUARY.— I have heard with regret of the death of Mr.
F. W. Henkel, who was a familiar figure at astronomical
meetings and an occasional contributor to this magazine.
Also of Professor Luis G. Leon, the energetic Secretary of the
Mexican Astronomical Society. He made its journal a most
readable summary of astronomical progress ; he visited
Greenwich a few months ago, and published an interesting
account of his impressions.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
ANTARCTIC LICHENS.— In his report on the lichens of
the Swedish Antarctic Expedition (Wiss. Ergcbn. Schwed.
Siidpolar-Exped., Band 4, 1912) Dr. Darbishire gives some
interesting details regarding the distribution of lichens gen-
erally in the Antarctic and Arctic regions. Up to the present
one hundred and five lichen species are known from the land
lying strictly within the Antarctic limits, and of these thirty-
two occur also in sub-Antarctic America, twenty-five in New
Zealand, and sixteen in South Georgia, showing a very close
affinity between the Antarctic lichen flora on the one hand
and the American and New Zealand lichen floras on the
other, the difference to the disadvantage of the latter being
accounted for by the greater nearness of the sub-Antarctic
American region to the extreme limit of the southern drifting
pack-ice. The lichens of sub-Antarctic America and New
Zealand are also very closely allied ; for out of the one
hundred and thirtythree lichen species of the former Mora,
one hundred and thirteen are found in New Zealand, thirty-
two in the Antarctic, and thirty-one in South Georgia, the
latter being evidently, from the phytogeographic point of
view, a half-way house on the road from sub-Antarctic
America to the Antarctic area. Moreover, about half of
the Antarctic species occur also in the Arctic regions.
Of the one hundred and six Antarctic lichens, sixty-nine are
crustose (encrusting forms which are applied so closely to the
rock that the latter has to be chipped off in order to get
specimens of the lichen), eighteen foliose (attached to the
surface at various points on the underside of the thallus, but
more easily removed than the crustose forms), and nineteen
fruticose or shrub-like (attached only at one point) : of these,
the numbers found in sub-Antarctic America are respectively
sixteen, five, and eleven. Of the sixty-seven species found
only in the true Antarctic area and nowhere else, forty-nine
are crustose, ten foliose, and 8 fruticose. The sub-Antarctic
American flora includes three hundred and six lichen species,
while seven hundred and forty have been found in New
Zealand : of the species common to the two regions fifty per
cent, are fruticose, thirty per cent, foliose, and only twenty
per cent, crustose. The affinities of the lichen floras of
sub- Antarctic South America and New Zealand lie mainly in
the fruticose lichens which are the oldest and probably the
least variable forms. The encrusting lichens are more
variable and have adapted themselves more readily to local
conditions, thus giving rise to new species.
Dr. Darbishire raises the interesting question of the re-
sistance to cold by lichens, and suggests some experiments
which might be made on these plants in the coldest regions.
For instance, it would be interesting to determine the amount
of water contained in the lichen thallus at different times and
seasons ; in what condition the lichens exist during the long
winter ; at what temperature assimilation begins, and so on. It
is of little use to make experiments on the plants in warmer
climates if we wish to ascertain how these lichens can live
under the adverse conditions prevailing in the polar regions.
Lichens are found everywhere on the outer limits of vegeta-
tion, and their chief ecological factor is their power to become
quite dry and yet remain alive. No doubt it is this power
which enables them to spread slowly but surely into the
bleakest and most inhospitable regions. They are making
their way towards the North and South Poles, and so far have
been beaten in their race only by the perpetual covering of
snow. If bare rocks are found in the neighbourhood of the
Poles themselves there is little doubt that lichens will be
found growing there.
VEGETATION OF NATAL.— An extremely interesting
account of the vegetation of Natal is given by Professor J. W.
Bows in the Annals of the Natdl Museum, II, 1912.
From the coast to the Drakcnsberg range, Natal presents
three terraces (about three hundred, six hundred and one
266
KNOWLEDGE.
July, 1913.
thousand metres respectively) with a mountain range above
one thousand five hundred metres. The chief rivers cut back
deeply into the higher topography, hence, in addition to the
main terrace system there is a system of river valleys at a low
level, and intervening ridges at a high level, introducing
greater complexity into the conditions affecting plant-life.
The soils are generally derived from poor shales and sand-
stones, but locally enriched by the frequent occurrence of
intrusive basic igneous rocks. A table of soil analyses is
given. Natal is a region of summer rainfall, and the higher
hills are moister than the valleys ; the rain clouds from the
Indian Ocean deposit first on the coastal belt, and the rising
edge of each successive terrace receives more precipitation
than the intervening terrace-plateaux ; mists also contribute
largely to the water-supply of the plants. Extensive meteoro-
logical tables are given in support of the author's conclusions
on the distribution of the vegetation in relation to climatic
factors — rainfall and temperature at different periods of the
year. There are great variations in illumination, from the
low intensity of the bush formation to the full light of the open
veld; details are given for various habitats. Interesting
details are given as to the influence upon the vegetation of
winds, fires, and animals (termites, locusts, caterpillars, earth-
worms, mammals) and man ; the effect of termites (" white
ants ") on the soil through their tunnelling and nest-building
is more than equalled by their direct effect on the vegetation
through their fungus-gardening and general scavengering opera-
tions. The plant formations and associations are described
and illustrated by excellent photographs, with lists of
species classified to indicate dominance and biological grouping.
The shore vegetation comprises (1) halophilous associations
on unstable sand, including Scaevola and Cyperus,
Ipomaea Pescaprae, and Mesembryanthemuin associations ;
(2) psammophilous bush formation on fixed dunes fifteen to
seventy metres high, forming a fringing belt along the whole
coast of Natal, as much as fifty miles broad in Zululand.and con-
sisting of trees with little undergrowth but many lianes;
(3) lagoon mangrove formation, an interesting outlier of the
Eastern mangrove flora with Avicennia officinalis,
Rhizophora mucronata, and Bruguiera gymnorhiza, at
the river estuaries where the sand-dune bush is interrupted
with a Salicornia herbacea association on mud-flats; (4) a
Barringtonia association just above the lagoons in wet
ground more sandy in nature and not brackish.
The inland vegetation consists of evergreen dicotylous
forest and grassland with summer rains and dry winters ; the
lower valleys have a dry climate, low winter temperature, and
a xerophytic vegetation. The forest is divided into (1) coastal
bush extending up to the edge of the first terrace, about five
hundred metres, on south-eastern slopes facing the rain-clouds
and sheltered from dry hot winds, with species which mostly
extend through tropical East Africa — Albizzia fastigiata and
Rhus longifolia dominant; (2) midland bush, also on the
south-eastern slopes and receiving the largest rainfall in the
region — vegetation in general similar to that of the coastal
bush, but with Combretum and Calodendron dominant ;
(3) yellow wood bush, forming the larger forest areas of
Natal, at one thousand metres and above, with Podocarpus spp.
and Olea dominant ; (4) rocky stream flora of the narrower
valleys, chiefly differing from the other three types in the
undergrowth which includes a rich and varied cryptogamic
flora— from its more variable and indefinite character it
apparently represents a migratory type in contrast to these
three types, which represent the formation on stable topo-
graphy ; (5) thorn veld or thorn savannah, including the
vegetation of the broader dry valleys, with trees (Acacia spp.,
and so on) scattered through the veld grassland.
The veld or grassland (grass savannah), widely distributed
in Natal, presents two types: — (1) high veld on the open soils
of the higher hills with the larger rainfall, with tall grasses which
flower regularly, Anthistiria imbcrbis usually dominant and
associated with Andropngon spp., Digitaria, and so on ;
(2) low veld on hard dry clays with valley frosts and low
rainfall, with more xerophytic grasses (low-growing, more
hairy), Anthistiria dominant but tufted and seldom flowering.
Associated with the veld grasses are numerous herbs, some of
which always flower immediately after the burning of the
grass ; the majority (including numerous bulbous monocoty-
ledons) flower early in the season soon after the first raius and
before the grass has grown tall enough to shade them ; and a
third class includes taller forms that grow with the grass and
flower late. In marshes on wetter parts of the veld the
dominant plants are grasses and sedges ; actual lakes are rare,
and often contain surprisingly few aquatic phanerogams, and
most of the marshes are dried up more or less completely in
the dry season.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon.), E.I.C.
THE FUTURE OF MOTOR SPIRIT.— The problem of
the future supply of motor spirit is discussed by Professor
V. B. Lewes in The Chemical World (1913, II, 111). The
trade statistics show that during the last seven years the
imports of petrol into Great Britain have risen from eighteen
million to eighty million gallons, whereas the increase in the
world's output of crude petroleum oil has only been from 28 -5
to fifty million tons. Most of the petrol imported into this
country has been derived from America and the Dutch East
Indies, but the increase in the demand in America has reduced
the supply available for export and has raised the price of the
crude oil.
Various methods are now being used to obtain a larger
yield of petrol from the crude oil. The gas escaping from the
wells in the oil-fields is collected and compressed, and the
light spirit thus obtained is mixed with the light fractions of
higher boiling-point separated in the distillation of the
oil. The specific gravity of the petrol used for motors is now
0-720, as compared with 0-680 when a larger supply of the
light fractions was available.
Methods have been devised whereby heavier fractions of
crude oils are converted into lighter products, such as, for
example, distillation in the presence of a catalytic agent like
nickel, or superheating the vapours while in process of
distillation.
In one American process a heavy petroleum fraction, termed
" solar oil," is sprayed together with water into an iron retort
packed with iron filings and heated to 600° C. The vapours
issuing from the retort are fractionally condensed, and yield
about thirty-nine per cent, of petrol, thirteen per cent, of
solvent spirit, and thirteen per cent, of varnish.
Professor Lewes points out, however, that crude petroleum
oil cannot be regarded as a lasting source of supply, and in
his opinion the motor spirit of the future will probably con-
sist of alcohol containing about ten per cent, of benzol.
At the present time about eight million gallons of benzol
are recovered in coke-oven plants, while the Scotch shale
industry produces each year about six hundred thousand
gallons of motor spirit.
A N EW I RON BACTERI UM.-A bacillus that has a specific
action upon solutions containing iron has been isolated by
Mr. E. M. Mumford (Chem. Soc. Proc, 1913, XXIX, 79), from
the Bridgwater Canal tunnels at Worsley, Lancashire. This
bacillus varies in its actions upon iron solution according as
to whether it acts in the presence or absence of air. Under
aerobic conditions the iron, whatever its condition of
oxidation, is precipitated as ferric hydroxide, while under
anaerobic conditions no precipitation of dissolved iron takes
place, although any ferric hydroxide already precipitated is
dehydrated and reduced to bog-ore. It is probable that in
nature these two actions take place simultaneously, and
account for the deposits of bog-ore found in various places.
The bacillus is a short organism about two microns in
length. It is motile and forms different involution forms. It
can be cultivated upon ordinary culture media and grows
readily upon potato, on which it forms greenish-brown nodules.
An enzyme has been separated from the bacillus, and this
also has the same specific action upon iron, its optimum
temperature of activity being 70° C. Both the bacillus and
its enzyme require the presence of nitrogen in the medium in
order to act upon the iron salts in solution.
July, 1913.
KNOWLEDGE.
267
EFFECT OF TARRED ROADS UPON VEGETATION
— -Various criticisms have been brought against the use of tar
upon roads on the grounds of their effect upon vegetation and
animal life, and a general outline of these is given in the
current issue of The Journal of Industrial and Engineering
Chemistry (1913, V, 428). In 1910 it was shown by MM. True
and Fleig (Comptes Rendus, 1910, CLI, 593) that although
bituminous vapours had but little influence upon the eyes
the dust from old roads produced, through its mechanical
action, inflammation and other troubles.
The following year M. Mirande (Comptes Rendus, 1911,
CLI I, 204) tested the effect of various coal tar products, such
as creosote and the like, and came to the conclusion that these
all had a destructive influence upon plant life, blackening the
leaves and causing death. Mainly on the results of this investi-
gation has grown up the belief that the tarring of roads is
injurious to the neighbouring vegetation ; but quite recently
this has been refuted by other investigators. For example, it
has been pointed out by French engineers that tar has been
used in Bordeaux for many years without any injurious effects
upon the trees. In another town, however, tar was apparently
responsible for the destruction of the trees in a large square ;
but here its action was purely mechanical, for it had been
spread so closely to the trunks that it prevented water from
reaching the roots.
The conclusions of M. Mirande have also been called in
question in Germany, and the results of experiments made by
Dr. H. F. Fischer to determine the point are to be brought
before the International Road Congress which will have met
(June) in London prior to the appearance of this note.
STUDIES ON THE ELEMENT ZIRCONIUM.—
Pure zirconium cannot be prepared by reduction with
aluminium or magnesium, but a product containing about
ninety-eight per cent, of the metal has been obtained by Herr
Wedekind (Annalen, 1913, CCCXCV, 149) by the following
method. Pure zirconium oxide was mixed with finely divided
metallic calcium, and the mixture placed in an iron tube, from
which the air was subsequently removed with an air-pump.
The reaction between the calcium and zirconium oxide was
started by heating the bottom of the tube, after which the
exterior of the tube was cooled by means of a current of air,
and finally by placing it in cold water.
After cooling, the contents of the tube were rapidly powdered,
and treated first with water, then with acetic acid, and finally
with dilute hydrochloric acid, care being taken to exclude air
throughout the whole process. This treatment was continued
until the whole of the calcium had been removed, the water
being then expelled, and the powder dried first in a vacuum and
finally at a high temperature in a porcelain tube from which
the air had previously been extracted. The final product,
which contained a small quantity of iron, had a specific
gravity of 6-44 in the melted state. It melted at 1530°C,
and at higher temperatures oxidised readily. The solidified
metal when filed and polished had a fine surface, which did
not tarnish on exposure.
A new compound, zirconium nitride (Zr3N2) was prepared
by heating the metal in an atmosphere of nitrogen, and
this could be decomposed by hydrogen at a high temperature
with the formation of the theoretical amount of ammonia.
IMITATION PEARLS FROM GELATIN.— An ingenious
adaptation of the process of diffusion of salts through a gelatin
film is described by Dr. R. Liesegang (Zeit. Chetn. hid.
Kolloide, 1913, XII, 181). It is based upon the fact that when
certain saline solutions diffuse into gelatin the film becomes
iridescent. The best results are obtained with dilute solutions
of alkali phosphates and pure gelatin in the form of a ten
per cent, solution. Beads intended to serve as the foundation
for the imitation pearls are dipped into the warm gelatin
solution and placed on a glass plate which has previously been
coated with gelatin. Round each bead is then painted a ring
of the ten per cent, phosphate solution, or in place of this a
mixture of the phosphate and gelatin may be used for coating
the glass plate.
Gradually there is a diffusion of the phosphate into the
gelatin, and the desired iridescent effect is obtained. Special
precautions are taken to prevent the beads drying too rapidly,
and finally the gelatin may be hardened and rendered in-
soluble by exposure to the vapours of formaldehyde.
OCCURRENCE OF FORMALDEHYDE IN PLANTS.
— A method of detecting formaldehyde in plant juices has
been discovered by MM. Angelico and Catalano (Gazz.Chim.
Hal., 1913, XLIII, 38). It is based upon the fact that the
plant Atractylis gummifera contains an active glucosidal
principle (atractiline) which gives a specific reaction with
formaldehyde, and will detect a mere trace of that compound.
When the juice of the plant is brought into contact with
atractiline and sulphuric acid, a violet coloration is imme-
diately produced when formaldehyde is present.
By means of this test the aldehyde has been detected in
the juices of eleven plants, including lupins, maize, and so on ;
and its formation is apparently connected with the chlorophyll
function. This is indicated by the fact that when the same
plants were kept for twenty-four hours in the dark no formal-
dehyde could be found. The juices and distillates from
several species of fungi contained no trace of formaldehyde.
GEOGRAPHY.
Bv Alex. Stevens, M.A., B.Sc.
BIOGEOGRAPHY OF THE ATLANTIC ISLES.— The
bathymetric charts of the Atlantic reveal a long submarine
plateau running along the axis of the present ocean and
bounded by symmetrical valleys on the east and west. The
surface of the plateau is irregular, rising into peaks which
project here and there in groups as the Atlantic Isles. Far
out the Azores rise from the " oceanic axis," while the
foundations of the Madeiras, the Canaries, and the Cape
Verde Islands lie in the eastern trough. These archipelagos
are of volcanic origin, and were the seat of a recent, Neolithic,
it is thought, and considerable vulcanicity. The Madeiras are
continuous with the Great Atlas. The materials of the
islands are uniform — trachytes, basalts, and tuffs — and all the
isles present the same appearance of towering mountains,
trenched by deep valleys, cut off at the sea by vertical cliffs or
running out into long promontories continued by tails of islets.
The ocean platform also is covered with lavas which were
certainly poured forth on dry land, but were covered by the
sea before subaerial denudation could leave its mark on them.
A second group of the Atlantic Isles embraces those in
the Gulf of Guinea and the distant Ascension and St.
Helena. But these are remnants of the foundered Gondwana-
land, and display a characteristic tropical African fauna.
Louis Germain (" Annales de Geographie ") has worked out
faunal and floral connections for the northerly groups,
particularly by means of insects and fossil and living molluscs;
but he draws evidence from other phyla, worms, and
arthropods generally. The islands are remarkably poor in
vertebrates, notably in mammals; and this poverty has been
used by Wallace, who considered the few vertebrates found
in the archipelagos to be imported, as an argument against
the possibility of a former continental connection. But
Scharff has shown that the mammals are indigenous and
came from Europe by a land passage, while Osborn, less
convincingly, derives the rabbit from America. It is a matter
for regret, nevertheless, that no traces of a possible extinct but
once flourishing mammal fauna have been brought to light
for purposes of comparison with American forms. On the
whole the much larger part of the fauna is circummediter-
ranean and the smaller American.
Where the Atlantic now rolls an old - time continent
supported a large and varied fauna and flora. By the close
of the Cretaceous the southern Gondwanaland portion was
passing beneath the waves and a narrow gulf divided the
northern part from America. Later, and perhaps within the
memory of the human race, this too — possibly the Atlantis of
Plato and the ancients, recalled only by uncertain oral
tradition — passed. The waters encroached from the west,
and the shore creatures of a fauna common to Atlantis and
268
KNOWLEDGE.
July, 1913.
America were driven farther east till the last bond with the
great eastern land-mass failed, and the ocean lapped the
bounds of Mauretania.
GREAT EXPLORERS. — The geographical journals have
recently been full of appreciations of Livingstone, and the
fact has emerged that it is at least largely as a geographer
that he will be remembered. To him is due a revolution in
African exploration, and to his influence can be traced a
beneficial effect on exploration generally. His mistakes, and
particularly his curious tenacity in entertaining certain pre-
conceptions in the face of contradictory facts gathered in his
own work, have been made much of by certain critics. The
wonder is that the accuracy of his observations and results
has never been impaired under the influence of his prejudices.
His maps show accuracy proportional rather to his energy in
utilising stray opportunities of gaining instruction than to the
extent of his training. It is related of him that he spent his
time on his first voyage largely in learning from the captain of
the ship how to determine positions by means of the sextant
and in mastering the art. The result is that some of the
stations he fixed were determined with sufficient accuracy even
for many modern requirements. No man has made greater and
more valuable changes on any map than he on the accepted
map of Africa: to realise this one has but to glance at the
series of maps earlier and later than his, published recently in
the magazines. By virtue of his inborn capacity for leader-
ship and the management of men, and his sympathetic
grasp, he was able not only to bring away stores of informa-
tion regarding the topographical and racial geography of
Africa, but to leave behind the influence of a master mind
and heart.
The Geographical Journal for June publishes an account,
by Sir Clements Markham, of Vasco Nunez de Balboa, that
singular man who reached Darien, " headed up in a cask," a
fugitive on the ship of Enciso. At the helpless fort of
Darien, in the midst of Indians, whose distrust and enmity
had been aroused by Spanish cruelty and injustice, he was
recognised as a born leader, and was obeyed by Pizarro
himself, who was actually in charge. He regained the con-
fidence of the natives, though with difficulty, and contrived to
render the existence of the hitherto wretched fort possible.
Informed by natives of the sea beyond the mountains which
was always calm, he it was who first of white men saw the
Pacific and stood " silent upon a peak in Darien." Superseded
by an incompetent and unscrupulous gold-seeker, who had
influence at Court, Nunez was nevertheless allowed to devote
the remainder of his life to building ships on the western
coast of the Isthmus for the exploration of the new ocean.
Materials were brought from Cuba and dragged with infinite
labour through the forest and over the mountains. But when
he was ready with three hundred men to launch his four
ships, he was " judicially " murdered by Pizarro and the
rapacious Pedrarias. With the ships of Nunez, Pedrarias
explored the coasts of Panama and Nicaragua. Nunez it was
who rendered possible the invasion of Chile and Peru. Had
he lived the conquest of the Incas had been earlier, and its
story had been different.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
THE CONCEALED COALFIELD OF YORKSHIRE
AND NOTTINGHAMSHIRE.— The proving of the concealed
coalfield to the east of the Permian escarpment which runs
from Nottingham along the boundary of the visible coalfield
into Yorkshire and Durham began in 1854, when the Duke of
Newcastle sank two pits at Shireoaks. Here the valuable
Top Hard Coal was obtained at a depth of one thousand five
hundred and thirty feet, and was found to be three feet ten
inches in thickness. By far the greatest progress in the
exploration of the concealed field, however, has been made
since the beginning of the present century. The chief areas
in which borings and shafts have been sunk are three in
number : one, to the south of Nottingham, has been developed
with a view to the London market ; a large area has been
proved in the central region between Nottingham and
Gainsborough, near the navigable Trent ; but the largest
development has been made in the Doncaster district, where
special transport facilities are available. The amount of
information thus gained has become so large and valuable
that it has become necessary to collect and summarise it in a
publication of the Geological Survey, which has been written
by Dr. Walcot Gibson.
The Nottingham and Yorkshire Coalfield is of the shape of
a basin, of which only the western rim is visible at the surface,
the remainder being concealed beneath successive sheets of
newer formations to the east. The eastern edge of the
concealed portion of the basin has not been reached in any of
the borings yet made. A thickness of about four thousand
feet of Coal Measures has been proved. Two borings each
end respectively in the Upper and Lower Coal Measures; all
the other borings and shafts end in the Middle Coal Measures.
The chief conditions which affect the accessibility of the
coal in the concealed area are the thickness of the overlying
strata ; the configuration, structure, and folding of the Coal
Measures ; and the amount of denudation, if any, suffered by
the latter before the deposition of the Permian. Where direct
observation is possible it has been found that the Permian
rests unconformably upon an even surface of the Carboni-
ferous rocks, so smooth that a well-known graphic method
has been applied to contour the surface of the hidden Coal
Measures. The contour lines thus obtained are strikingly
parallel, and show that the buried surface has a remarkably
uniform slope directed a little to the north of east, and oblique
to the north-west strike of the Coal Measures. Hence higher
horizons in the Coal Measures tend to occur beneath the
Permian cover than at the outcrop. At Kelham and Thorne,
however, borings have shown that the Coal Measures rise, at
least locally, on approaching the Trent ; and if the general
slope of the buried surface (ninety to one hundred feet per mile)
is maintained here, the whole of the Coal Measures will be cut
out by the newer formations. The area of the concealed
coalfield already proved amounts to one thousand two hundred
square miles.
ORIGIN OF TURQUOISE.— A theory of the origin of
turquoise has been propounded by S. Paige (" Economic
Geology," 1912, 382-92) to account for an occurrence of this
gemstone in the Burro Mountains of New Mexico. The
country rock is a Pre-Cambrian granitic complex, which has
been intruded by quartz-monzonite with intense fracturing
and mineralisation. The turquoise occurs in small veins
within both the igneous rocks, and the veins are closely related
to the surfaces of denudation. The author believes that the
turquoise was formed by the oxidation of copper sulphides
and pyrite in the zone of weathering, and the reaction of the
resulting solutions with apatite. The latter would supply the
necessary phosphorus to combine with the copper and
aluminium of the solutions and thus form turquoise.
AN ENGLISH DESERT— The Long Valley, Aldershot.
is described by Alan G. Ogilvie in the June Geographical
Journal as an area which exhibits many of the phenomena
characteristic of deserts. The desert features, however, are
not due to aridity, but to the ceaseless erosion effected by the
hoofs and wheels of cavalry and artillery. This action has
completely stripped the area of the original mat of vegetation,
and has exposed the underlying sand and gravel to very rapid
erosion. The Long Valley is now dissected by a system of
stream -courses which reproduce all the essential features of
desert wadys. These are only filled after heavy rain, and
then contain rushing torrents which carry down large masses
of sand and gravel. Ordinary rain showers have no effect, as
the water percolates at once through the sand. Similarly the
water from a continuous spring loses itself in the sand after
running in a well-formed valley for about a hundred yards.
The erosion due to wind is, however, more important than
that of water. The wind is producing a steady lowering of
the surface of the valley by blowing away the lighter particles.
The finer dust is probably carried beyond the confines of the
area, but the blown sand tends to form miniature dunes on its
July, 1913.
KNOWLEDGE.
269
margins, especially at the north-east corner facing the prevalent
wind. The desert appearance of the Long Valley is shown in
a series of striking photographs which illustrate the disastrous
and desolating effects of the removal of vegetation from an
area the climatic conditions of which do not differ from those
of the surrounding districts.
METEOROLOGY.
By William Marriott, F.R.Met.Soc.
WINDS IN THE FREE AIR.— At one of the Friday
evening discourses at the Royal Institution Mr. C. J. P. Cave
dealt with the subject of the " Winds in the Free Air." He
has for some years devoted a considerable amount of time
and work in carrying on observations in the upper air, first by
means of kites and subsequently by small rubber balloons, the
movements of the latter being followed by a specially
designed theodolite. The lower layers of the atmosphere up
to one or two kilometres are the most important to aviators.
To meteorologists the higher layers offer problems of greater
interest. In considering the winds in the free air it is con-
venient to have some datum to which to refer them, and this
is known as the gradient wind. Mr. Cave divides the wind
structures into five types. In the first three the wind
increases above the surface and equals the gradient velocity
at a height of half a kilometre or so; above this, in the first
class, the wind remains more or less equal to the gradient
velocity up to a height of seven or eight kilometres ; in the
second class the wind in the upper air greatly exceeds the
gradient wind ; and in the third class it falls off again to a
lesser value; but in all three classes the direction remains
much the same as that of the gradient wind. There are often
cases of reversals when the wind in the upper air is very
different in direction from that near the surface, and when it
bears no relation to the surface-pressure distribution. In
cases of reversal it is found that the warm wind flows over the
top of the one that comes from a colder region ; there must
somewhere be a line where the warm current is rising, where
it must be cooled dynamically, and where its moisture may
condense into cloud or rain. It is interesting to note that in
most cases rain occurs somewhere in the region of the reversal,
and in summer thunderstorms are frequent. The last type of
wind structure considered was the outflow that seems to take
place from the upper layers over a low-pressure system,
causing west to north winds in the upper air on the east and
south sides of the depression.
Following on inquiries made by Mr. W. H. Dines on the
correlation between the surface pressure and various
meteorological elements at a height of nine kilometres, Dr.
W. N. Shaw has suggested that the changes of pressure to
which our changes of weather are due have their origin, not
near the surface of the earth, as hitherto supposed by many
meteorologists, but just below the level of the stratosphere at
a height of nine kilometres or so above the surface. Mr. Cave
says that this view is in accordance with the observed facts of
the wind distribution in the different layers of the atmosphere.
HOURLY OBSERVATIONS OF CLOUD FORMS.—
Mr. Spencer C. Russell, who has always been a keen observer
of clouds and thunderstorms, gave, at the May Meeting of the
Royal Meteorological Society, the results of monthly and hourly
cloud-form frequencies at Epsom for the eight years 1903-
1910. He had observed during this period, almost single-
handed, the amount of cloud and also the various forms of
cloud visible at each hour, day and night. This was truly a
most remarkable feat of endurance, but it is a valuable
addition to this little-studied branch of meteorological science.
He arranged the fifteen varieties of clouds into four groups,
viz. (1) upper, (2) intermediate, (3) lower, and (4) clouds of
diurnal ascending currents. The upper clouds, which include
the Cirrus, Cirro-stratus, and Cirro-macula, show a marked
prevalence during the summer with minima during the winter.
Morning and evening maxima, with a midday decline, are
common to all these varieties. The intermediate clouds,
which include Cirro-cumulus, Alto-stratus, Alto-cumulus,
and Cumulo-stratus, are also more prevalent in the summer
than in the winter. The lower forms, which include Strato-
cumulus, Nimbus, Fracto-nimbus, Fracto-cumulus, Stratos,
and Fog, attain their maxima in the winter months, their
minimum frequency being in the summer. The clouds of
diurnal ascending currents, Cumulus and Cumulo-nimbus, are
independent of any seasonal variation in hourly frequency,
the maxima, at noon and 3 p.m. respectively, taking place at
these hours in every month of the year.
The total number of individual records made by Mr. Russell
approximate close upon 100,000. The Cumulus cloud yielded
the greatest number of daily values (1,622), the Stratus coming
next (1,155), but the Stratus had the greatest number of
hourly records (13,497), the Cumulus being next (11,414).
METEOROLOGY AND MAGNETISM AT THE
ROYAL OBSERVATORY, GREEN WICH.— In his Report to
the Board of Visitors of the Royal Observatory at the Annual
Visitation on June 7th the Astronomer-Royal gave particulars
respecting the meteorological and magnetic work carried on
at Greenwich. The chief results for the twelve months ended
April 30th, 1913, were: The highest temperature in the shade
(recorded on the open stand) was 90°-0 on July 12th. On
twelve days the highest temperature equalled or exceeded
80° -0, but none of these days occurred after July, maximum
readings of 70° and upwards occurring only seven times in
August, and not at all after. The lowest temperature during
the same period was 24° -2 on February 23rd. There were
twenty-seven days during the winter on which the temperature
fell as low as 32°, or less than half the average. The mean
temperature for the twelve months was 49°- 8. The mean
daily horizontal movement of the air was three hundred and
ten miles, which is twenty-six miles above the average of the
previous forty-five years. The greatest recorded daily move-
ment was eight hundred and forty-five miles on March 19th,
and the least fifty-six miles on October 11th. The total rain-
fall was 25-61 inches, or 1-49 inches greater than the average.
The number of hours of bright sunshine was one thousand
three hundred and thirteen out of a possible four thousand
four hundred and fifty-seven hours, giving a mean proportion
of 0-295, constant sunshine being represented by one. As
compared with the previous twelvemonth the deficiency of
.more than five hundred hours is fully accounted for by the
fact that in July, August, September, and April the duration of
sunshine was only about half what it was in the corresponding
months.
The magnetic elements for 1912 determined from obser-
vations in the Magnetic Pavilion are as follows : —
Mean declination 15° 24'-3 West
Mean horizontal force ... 0-18528 (in C.G.S. units)
Mean dip 66° 51' 46"
The Astronomer- Royal stated tnat in the new magnetic
observatory shortly to be erected provision is made for the
continuation of the long series of Greenwich observations of
the variations of the magnetic elements. This series is
unique as regards the length of time during which observations
have been made on the same site. The care which has been
taken to guard the observatory from all artificial electro-
magnetic disturbances which could affect the accuracy of the
observations has preserved the suitability of the site for such
work. The present wooden structure, however, is old, and
needs extensive repairs or renewal. The latter course was
considered preferable, and designs have been prepared for a
new building in the Magnetic Pavilion enclosure in the Park,
where the absolute observations are made. The main feature
of the building is the provision by insulation and heating for
the reduction of the daily range of temperature. Also, to
avoid damp, it will be above ground. The building will
therefore be adapted to house a set of modern instruments.
Although the change of site is small, the new and the old
instruments will be run concurrently for a period sufficient to
give a good comparison between the two.
THE ATMOSPHERIC TURBIDITY OF 1912.— The
great deficiency of bright sunshine referred to above was not
confined to Greenwich only, and it was no doubt connected with
270
KNOWLEDGE.
July, 1913.
the unusual haziness that overspread most of the northern
hemisphere during June, 1912. This appears to have been
the result of the eruption of Katmai Volcano in Alaska. This
volcano became suddenly active on June 6th, and violent
explosions were frequent during the three days that followed.
The eruptions continued with greatly diminished energy until
the end of October, and perhaps until the end of the year.
Professor H. H. Kimball, of Mount Weather Observatory,
U.S.A., who has been investigating the subject, has found that
in connection with the atmospheric haziness noted by many
observers, but more especially by those engaged in astronomical
photography, there was a decrease in atmospheric transparency
of from ten to twenty per cent. The solar radiation intensities
measured at the Mount Weather Observatory, after June 9th,
1912, were below the average, and the percentage of polarisa-
tion of skylight on cloudless days was abnormally low. These
low values seem to be due in some measure to volcanic dust
in the upper atmosphere.
INTERNATIONAL METEOROLOGICAL COM-
MITTEE.— A meeting of this Committee, which consists of
representatives of the principal meteorological services in
various parts of the world, was held in Rome from April 7th to
12th. Dr. W. N. Shaw, F.R.S., the Director of the Meteoro-
logical Office, London, is the President, and Dr. G. Hellmann,
the Director of the Royal Prussian Meteorological Institute,
Berlin, is the Secretary of the Committee. Among the
subjects which came up for consideration were Weather
Telegraphy, Weather and Agriculture, Investigation of the
Upper Air, Meteorological Units, Sunshine Recorders, and
Storm-warning Signals.
MICROSCOPY.
By F.R.M.S.
AN APLANATIC AND ACHROMATIC CONDENSER.
— An attempt to modify the or-
dinary refracting substage conden-
ser used for observation with
transmitted light, so as to render
it available for use as a dark-
ground illuminator, has led to the
construction of an Aplanatic and
Achromatic Condenser. The or-
dinary condenser of N.A. 1.40,
which consists of three lenses,
though corrected for neither spher-
ical nor chromatical aberration,
is nevertheless available as a
means of producing dark-ground illumination, but its deficient
chromatic correction gives rise to colour effects which inter-
fere with the quality of the resulting image : this defect can be
remedied by achromatising the condenser. This quality alone
would not, however, have placed the condenser on a level with
the reflecting condensers, seeing that these, in addition to
being naturally achromatic, are also excellently corrected with
respect to spherical aberration. To compete with these the
refracting condenser must needs be aplanatic as well as
achromatic.
To meet this requirement the condenser constructed in
1907-8 by Leitz has recently been further improved in the
matter of spherical correction. In the majority of cases
objects which are observed with dark-ground illumination are
examined in an aqueous medium, having a refractive index
barely exceeding that of water, i.e., 1-33. Every ray whose
aperture is numerically greater than the refractive index
of the medium containing the objects is totally reflected at the
surface of the medium, as can be easily shown by a simple
calculation, and the rays so reflected do not contribute to the
illumination of the object. In order that the whole of the
light which a condenser is capable of receiving when opened
to its full aperture may be brought to bear upon the prepara-
Figure 271.
The Condenser.
tion, the condenser must have an aperture of 1.33, that being
the refractive index of water.
The new condenser has lenses of the same diameter as the
older type with N.A. 1 -40 ; however, when used with aqueous
media, it produces a more brilliant illumination than the
latter. In the most recent form of the reflecting condenser,
the so-called Concentric Reflecting Condenser, we have also a
practical application of the above reasoning."1
As will be seen from Figure 271, the condenser con-
sists of two doublets on either side of a meniscus and a
hemispherical front lens. In its general construction it
resembles an oil-immersion lens and, as a matter of fact, it is
computed on precisely similar lines.
Although the condenser has been corrected as an
immersion condenser its qualities will be impaired only very
little when being used dry if the layer of air between
condenser and slide is kept as thin as possible. In this case,
however, the aperture is reduced to N.A. 1-0, since all rays
of higher aperture are totally reflected.
In addition to being both achromatic and aplanatic, this
condenser also satisfies the sine condition.
The focal lengths are 14-5 in immersion contact and 9-6
millimetres dry, and the effective aperture of the back lens is 26
millimetres. The light-transmitting power of the condenser is
at least not inferior to that of a condenser constructed of single
lenses of similar diameter ; the loss of light due to absorption
in its passage through the six lenses of the new condenser is
fully compensated for by the manner in which the rays
appertaining to the different zones are brought to a focus.
This quality, coupled with the other conditions which are
satisfied by the formula of the condenser, furnishes an
efficient means of projecting a sharp, even, and colourless
image of the source of light in the plane of the object ; in the
methods of photomicrography this is of great importance.
Continuous use and practical experience must show whether
the refinements in the correction of the aplanatic condenser
and its large aperture will secure tangible results in ordinary
microscopic observations with transmitted light, both direct
and oblique, especially in the case of objects which are diffi-
cult to resolve. Under the conditions of dark-ground
illumination the excellent correction of the aplanatic condenser
shows itself in an unmistakable manner, and every effort has
been made to provide the condenser with qualities that will
satisfy all the most advanced requirements of modern observa-
tion by this method of illumination. The extent to which
the spherical aberration has been successfully corrected is
clearly shown by the photograph reproduced in Figure 276 of
the path, within fluorescent uranium glass, of the intersecting
pencils of rays, which method was first used by the firm of
Ernst Leitz in 1910. It will be seen that the pencils
intersect within a very small area, and this furnishes an
estimate of the resulting brightness of the illuminated field.
By reason of the excellent correction of spherical and chro-
matic defects, and since also the sine condition is satisfied,
the objects can be illuminated on a dark ground in such a
manner that the image is seen free from colour, without
distortion, and without disturbing flares.
The requisite conditions for observation against a dark
background are established by the use of a central stop (see
Figure 273) which rests on the carrier of the iris-diaphragm.
The illumination is derived from the peripheral zones only
of the pencil of light : these pencils are indicated by dotted
lines in the annexed diagram, which shows the path of the
rays through the aplanatic condenser and an oil-immersion
lens. The image as seen in the microscope (see Figure 277),
derives its existence exclusively from refracted and diffracted
light emitted by the object.
The following points respecting the central stop may be
noted. The disc of the smallest central stop, which is
attached to the outer ring by three radial arms, has a
diameter of 16 millimetres, and bears the number 0-85,
whilst the ring is inscribed 1-33. All parallel rays entering
the condenser within the annular zone, corresponding to an
• Cf. F. Jentzsch, Ueber Dtmkelfeldbeleuchtung, Phys. Zcitschr., XI, 1910. pages 993-1000; Verhandl. dcr D. Physik.
Gesellschaft, XII, 1910, pages 975-91.
July, 1913.
KNOWLEDGE.
271
Figure 272.
A Liliput arc-
lamp placed in
position for use
with the con-
denser.
Figure 273.
Central stop.
Figure 275.
An objective with
the nickel-plated
part unscrewed.
Figure 276.
1'he intersecting pencils of light within fluorescent uranium glass
Figure 274.
Two of the loose
discs.
Figure 278.
Snapshot taken
upon an ortho-
chromatic plate
with the aid of a
screen. Repro-
duced from a
platinum print.
(See page 274.)
Figure 277.
Diagram of the condenser and
an immersion objective. The
dotted lines indicate the pencils
of light.
272
KNOWLEDGE.
July, 1913.
Figure 286. P. pttlchellum Jenyns.
Figure 279. P. ainnicum Miiller.
Figure 287. P. subtruncatum Malm.
Figure 280. P. attartoides Sandb.
Figure 281. P. casertanum Poli.
Figure 282. P. nitidum Jenyns.
fe
J
Figure 288. P. henslowanum Shepp.
Figuue 289. P. supinum A. Schmidt.
Figure 290. P. steeabuchii M oiler.
Figure 291. P. lilljeborgii Clessin.
^^J ^^^
Figure 283. P. personatum Malm.
Figure 292. P. hibernicum Westld.
v
Figure 284. P. pusillum (Gmelin) Jenyns.
Figure 285. P. milium Held.
I^W) ^B
Figure 293. P. obtusalc (Lam. ?) Jenyns.
*
■*>*&.
/ #>
Figure 294. /J. vincentianum B. B. Woodw.
The fifteen British Species of Pisidia recognised by Mr. B. B. Woodward in the Catalogue recently published by the
British Museum (Natural History), and a New Species described by himself.
July. 1913.
KNOWLEDGE.
273
apertural range extending from 0-85 to 1-33, are allowed to
participate in the illumination. The objectives employed for
observation should in these cases have apertures which are
less than N.A. 0-85, such as the Leitz objectives, Nos. 2 to 5,
having respectively focal lengths ranging from 24 to 5-4
millimetres, as well as the apochromatic lenses of 8 millimetres
and 16 millimetres focus. To use high-power objectives,
.having apertures exceeding N.A. 0-85 in conjunction with the
central stop, it becomes necessary to reduce their aperture to
less than N.A. 0-85 by a stop situated behind the back lens.
To modify the range of the peripheral zone three loose
discs, two of which are shewn in Figure 274, bearing the
following numbers, 1-0, 1-1, 1-2, are provided with the
stop. Each disc has a central hole fitting a small pin at
the centre of the immovable disc inscribed 0-85. When
one of these discs is pressed down upon this pin the cone of
illumination becomes reduced, so that an aperture of 1-0,
i-1, and 1-2 is respectively employed; these discs are
used when observing with objectives having an aperture
of 1'0. Oil-immersion lenses have their aperture reduced
to 1-0 for observation with dark-ground illumination by
unscrewing from the body of the objective the nickel-
plated part of the mount (see Figure 275), which con-
tains the optical system, and screwing it to an adapter fitted
with a conical stop, which is so arranged that it cuts off all
rays which would pass if the numerical aperture of the lens
were greater than 1-0. In the case of dry lenses it is gene-
rally desirable, to obtain an intensely dark background, to
employ one of the larger stops ; in the majority of cases the
one marked 1 ■ 0 is sufficient for this purpose. For observation
with dark-ground illumination it is always an advantage to use
objectives of high degree of chromatic correction — for instance,
fluorite lenses or apochromatic lenses — since under the
conditions of dark-ground illumination the residual colour
defects of the lenses, known as the secondary spectrum, are of
much greater importance than is the case in ordinary observa-
tion with transmitted light. The best source of light to use
with dark-ground illumination is the Liliput Arc Lamp, which
has been specially devised for this purpose. This lamp burns
carbons set at right angles to one another and consumes five
amperes: it is so arranged that it may be connected with the
ordinary domestic electric supply by means of a plug contact.
The light emitted by this lamp is rendered parallel by a con-
densing lens attached to the lamp casing, and is reflected by
the plane mirror of the microscope into the condenser, the
latter being adapted for parallel light. The lamp, being hinged,
moves in a vertical plane, and should be so set that the plane
mirror may be completely filled with light. The lamp should
be placed at such a distance from the microscope that the
observer may be able to manipulate it without inconvenience,
as shown in Figure 272. When using dry lenses a ground-glass
screen may be interposed between the lamp and the mirror;
the contrast between a dark-ground and a brightly illuminated
object is thereby intensified. When using low-power lenses
having apertures not exceeding 0-40 the condenser may be
used dry ; with lenses of higher power the condenser should
be used in immersion contact with the object slide ; it will
generally be sufficient to employ water as the optical medium.
The adjustment of the dark field is not always an easy matter
with high-power lenses ; it may, however, be greatly simplified
by the following procedure : —
The object should be viewed first with an objective of
medium power, say No. 3 Leitz Objective, in conjunction with
a high-power eyepiece. Incidentally it may here be noted
that high-power oculars are particularly useful in observations
under dark-ground illumination. Focus the lens in the plane
of the object, the object slide being at this stage connected to
the condenser by a drop of oil. By the requisite movement
of the substage mirror direct the light upon the object.
Under good conditions of adjustment the circle of bright
light should appear in the middle of the field of view, and it
should be sharp and free from colour. The condenser should
be raised or lowered until the spot of light becomes as sharp
as it is possible to make it. Having prepared the adjustment
in this way a very small correction in the position of the
mirror and condenser will be needed to secure a very perfect
dark ground. These manipulations are sufficient to obtain
the necessary adjustments, and there is no need to have
recourse to centring screws.
The transition from dark background illumination to
ordinary observation with transmitted light, and vice versa,
can only be made in the case of a refracting and not in that of
the usual reflecting condenser ; for this purpose a useful
special arrangement has been devised.
The ordinary conical stop with which lenses of high aper-
ture are fitted to render them available for observation with
dark-ground illumination is replaced by a small iris-diaphragm
fitted to the body of the lens mount. When the lens is used
for observation with an ordinary bright field this diaphragm
should be opened to its full extent, and it should be partly
closed for observation with dark-ground illumination. In
order to pass rapidly from one mode of illumination to the
other the iris-diaphragm carrier below the condenser is
provided with a central stop attached to a slide by means of
which it may readily be pushed in or withdrawn.
It may be useful to point out the distinctive features of a
refracting condenser. In the case of a reflecting condenser
the course of the rays is solely determined by a series of
reflections. In refracting condensers the illuminating pencils
are brought to a focus by refractions at the surfaces of the
constituent lenses. In addition to these refractions, however,
the rays undergo certain reflections which may impair the
distinctness of the image as seen in the dark-ground field. It
seems almost hopeless to construct an aplanatic and
achromatic condenser which needs correction by the use of
so many kinds of glass and refracting surfaces, and in such a
way that every surface must be excluded from which reflected
rays after successive refraction and reflection shall yet leave
the condenser at such an angle as to enter the plane of the
object. These indirect rays which cannot altogether be
avoided, however faint they may be, impair the blackness of
the background which is never the same as that obtainable
with a reflecting condenser, and under these circumstances
the clearness of the image may suffer.
The condenser described above, on the other hand, has the
advantage of being of the nature of a universal illuminator,
and in this respect it surpasses all existing reflecting con-
densers. Primarily, a highly refined illuminator adapted for
the various purposes of visual microscopy with transmitted
light and photo- micrography, its performance as a dark-
ground illuminator entitles it to a prominent position among
the condensers devised for this purpose. Far from being
restricted in its use to high-power objectives, it illuminates a
sufficiently large field to render it suitable for use with low-
power objectives whose focal lengths may be as much as
twenty millimetres. The only optical device of the nature of a
reflecting condenser which can be regarded as a dark-ground
illuminator is our old friend the concave mirror : this can be
converted into a makeshift for a dark-ground condenser by
covering up the central portion of the mirror. Owing to its
small apertural angle the mirror can be used in this way only
in conjunction with lenses of a very low power.
C. Metz, Wetzlar.
THE BRITISH SPECIES OF PISIDIUM — Those
who study British land and freshwater shells — and they are
many — owe a deep debt of gratitude to Mr. B. B. Woodward
for determining what species of Pisidium are British and
for clearing up all the doubts and difficulties which have
long surrounded these small freshwater bivalves. After
examining many thousands of specimens under the microscope,
and devoting his leisure hours during nine winters to the
subject, he has come to the conclusion there are fifteen
British forms worthy of specific rank, of which all but one
(P. astartoides) are still living in this country. Photographs
of these by the kindness of Mr. Woodward we are permitted
to reproduce on page 272 (see Figures 279 to 293).
The determination of the species is based to a large extent
upon the hinge characters of the shell and the form and
position of the various hinge " teeth."
P. casertanum (see Figure 281) is a species which haslong
been known on the Continent under this name or that of
274
KNOWLEDGE.
July, 1913.
P.fontinale. P.nitidum Jenyns(see Figure 282) still stands,
and Mr. Woodward points out that it has frequently been
mistaken for small specimens of the last species, P. personatum
or P. pusillum. P. personatum (see Figure 283) was recorded
as British by Mr. Woodward in 1908. This, again, has often
been confounded with other species, and its detection has
helped very greatly to clear matters up. P. pusillum (see
Figure 284), P. millium (see Figure 285), and P. pulchellum
(see Figure 286) still stand. P. subtruncatum was
identified as British by Dr. Johansen, who pointed it out
to Mr. Woodward in 1901 (see Figure 287). This was
looked upon as a variety of pulchellum by Jenyns,and is the
var. pallida of Jefferys' P. fontinale. P. henslowanum (see
Figure 288) is recognised by Mr. Woodward. P. supinum
was found by Dr. Johansen near Kew Gardens in 1901. Mr.
Woodward describes P. parvulum, which has not yet been
met with in Britain, and is the smallest of the Western
European species. P. steenbuchii, P. lilieborgii, and
P. hibernicum (see Figures 290 to 292) are species that were
not recognised till recently. P. obtusale (see Figure 293)
is an old friend. We figure also P. vincentianum, a fossil
form from the Pleistocene of Belgium, which is a new species
described for the first time by Mr. Woodward, but which has
not yet been discovered in this country (see Figure 294).
Mr. Woodward's researches have been published by the
British Museum (Natural History) as a catalogue consisting
of one hundred and forty-four pages and thirty plates, the
greater part of which latter consists of collotype reproductions
of photographs of many hundreds of shells. In the case of
every species the hinges and hinge-teeth are described in
great detail. Symbol maps (in accordance with those agreed
upon by the British Association Committee for " The Forma-
tion of a Definite System on which Collectors should record
their Captures ") are also given, which show recent as well as
fossil records. A detailed list of localities for each species
is also included, and the synonomy, which in some cases runs
into two or more octavo pages, gives some little idea of the
work which Mr. Woodward has accomplished. Every
collector of land and freshwater shells will now have to check
his specimens of Pisidia and redetermine them with the
help of Mr. Woodward's book which can be obtained at the
British Museum (Natural History), Longmans, Green & Co.,
B. Quaritch, or Dulau & Co. Price 10/6 net. w M w
ORNITHOLOGY.
By Wilfred Mark Webb, F.L.S., F.R.M.S.
THE COMMITTEE FOR THE ECONOMIC PRESER-
VATION OF BIRDS.— We learn from the July number of
The Selborne Magazine that at the meeting of the Council
of the Selborne Society, held on November 26th, 1912, Mr.
Holte Macpherson and the Secretary were empowered to
confer with Dr. Chalmers Mitchell and others, including
members of the trade, as to the best steps to be taken to
preserve birds which are being killed off for their plumage.
Subsequently Mr. Macpherson, Mr. Poole, and the Secretary
were given formal authority to represent the Society on the
Committee for the Economic Preservation of Birds, to which
also the London Chamber of Commerce has appointed
representatives. Many leading zoologists have joined the
Committee which is now beginning active work.
In the past, bird-lovers have sought to secure legislation
without stopping to consider whether the objects they seek
will be obtained. On the other hand the trade has occupied
itself with opposing all legal measures, and nothing has been
done. It is hoped, however — now that naturalists and
merchants are combining to consider the question — that some
steps will be taken to preserve birds whose plumage is used in
commerce. Anyone who has evidence to offer with regard to
the killing of birds for trade or natural history purposes is
invited to communicate with the Honorary Secretaries of the
new Committee, care of the Selborne Society, 42, Bloomsbury
Square, W.C.
PHOTOGRAPHY.
By Edgar Senior.
PLATINUM PRINTING.— Of the many processes of
photographic printing there are few which equal in simplicity,
together with the beauty of the results obtainable, that known
as platinum printing (see Figure 27S). For while it is capable
of rendering shadow detail in a most perfect manner, it is at the
same time able to reproduce all the delicate gradations in the
lights. Then there is the additional advantage of permanency,
for which both platinum and carbon stand pre-eminent, and
although the former does not enjoy the advantages attending
the latter, of giving an almost unlimited choice of colours,
both warm or cold blacks and sepia are readily obtainable.
The papers manufactured by the Platinotype Company,
Gevaert Limited, and others are of several grades or kinds,
which refer to the surface, texture, and thickness. As the
paper has a great affinity for moisture, special precautions
have to be taken to keep it in a perfectly dry atmosphere,
and neglect of this is a great cause of so many failures in
practice. Therefore, in order to keep the paper in good
condition, it is sent out by the makers in sealed-up tins
containing a small quantity of a desiccating agent (calcium
chloride) which absorbs the moisture contained in the air
enclosed in the tin. In this manner the paper will keep
perfectly dry for a lengthened period, the writer having found
it to be in perfect condition after the expiration of two
years. As soon, however, as the tin is opened the paper must
be removed to a storage tube which is provided at one end
with a receptacle for containing the calcium chloride, and this
salt must be frequently dried and replaced in the tube ; in fact,
it cannot be too strongly urged upon those who use platinum
paper to keep their tins in a dry place, as well as keeping the
calcium chloride dry. If these points be attended to there
will not be any difficulty in preserving the paper in good
condition. Neglect of these simple precautions is seen in the
fiat, muddy, sunken-in appearance of the image. One of the
first considerations is the kind of negative that will give
the best result by this process ; it may, however, be taken
for granted that any negative which possesses good gradations
from high lights to shadows will yield a good print, but that
poor, flat, or thin ones will not be suitable as a rule. Before
commencing printing, it is necessary to dry the printing
frames, and especially the backs, thoroughly before a fire.
The negative is then placed in the frame and the coated
surface of the paper in contact with it, this operation being
conducted in as subdued a light as possible, as the
paper is much more sensitive than the P.O. P., and
the effect of short exposure to light is not apparent until
after the print is developed. In order to protect the paper
from moisture during the time of printing it is usual to place a
piece of vulcanised rubber upon it before placing the back of
the frame in position ; several sheets of waterproof paper can,
however, be made to answer instead. The paper before
exposure to light is of a lemon-yellow colour ; as the printing
proceeds it changes to a greenish-grey, the shadows finally
becoming a blue-grey and with some negatives a slight orange-
brown colour. It is not advisable, however, to continue the
printing until the detail in the lights is plainly visible. The
time of exposure necessarily varies with the kind of negative,
but it is about one third of that required for a silver print. It
is evident that the progress of printing can be inspected from
time to time ; but as over-printing is not made apparent until
development has taken place, some amount of experience is
required to know when printing should be stopped. This
knowledge, however, will soon be acquired after a few trials.
But it does constitute a vital point in the process. If thought
desirable, one of the many forms of actinometers may be
employed in printing, although they are of little use unless a
number of prints are required from one negative ; in which
case they are a help in ensuring that the printing shall
be carried to the same depth in each case. The printing
having been carried far enough, the next operation is that of
development. This may be carried out at once, or the
exposed paper may be returned to the calcium tube until a
July, 1913.
KNOWLEDGE.
275
more convenient time. The reason of its being necessary to
develop the print is owing to the light having acted upon the
iron salt only, and before the product formed is able to reduce
the platinum salt in contact with it it becomes necessary to
float the exposed paper upon a solution of either potassium
oxalate or a mixture of this with sodium phosphate, known as
developing salts. Using the former, a stock solution is made
as follows : —
Oxalate of Potash
Water
16 oz.
54 oz.
For use one part of this is diluted with two parts of water.
If this bath is made slightly alkaline with carbonate of soda
or potash it gives slightly warmer tones, and if made slightly
acid by means of oxalic acid, a colder or bluish colour results.
In either case the alkalinity or acidity should only be such as
to just alter the colour of the test paper used. If developing
salts are used, then a stock solution of the following strength
is prepared : —
Developing Salts ... ... $ lb.
Water 50 ozs.
And for use one part is taken to which is added one part of
water. It is claimed for this developer that it gives better
half-tones, as well as a colder tone generally. Whichever
developer is employed, the print is floated face downwards
upon it, the print being then turned over to watch the progress
of development, which should be complete in about thirty
seconds. The temperature of the solution should be from
60° to 100° F. If the solution be below 60° the deposit is liable
to become granular, while if too hot there is a tendency to a
brown and muddy colour, although under-exposed prints may
frequently be saved by use of a warmer solution for their
development. As soon as the desired result is obtained the
print is placed into a dish containing a dilute solution of
hydrochloric acid, the strength being —
Hydrochloric Acid (pure)
Water
1 oz.
100 oz.
The prints are allowed to remain in this bath for ten minutes,
after which they are transferred to a second bath of the same
nature, and finally to a third, remaining for ten minutes in
each. After this they are washed for about half an hour in
several changes of water, a little carbonate of soda being put
into the last washing water to ensure the removal of all trace
of the acid. If the prints on removal from the water are
placed between blotting boards and allowed to dry slowly,
they will be found to remain perfectly flat and ready for
mounting by any method that may be thought most desirable.
PHYSICS.
By Alfred C. G. Egerton, B.Sc.
IS SODIUM RADIOACTIVE? — It is a somewhat
striking fact that potassium and rubidium are radioactive ;
that is, they emit spontaneously radiations consisting of
negatively charged particles, or 0-rays. The electrical effect
produced by these rays from potassium is only about a
thousandth of the effect produced by the radiations from an
equal weight of uranium. Experiments seem to show that
this small effect is due to /3-particles spontaneously emitted
from the potassium or rubidium atom, and that these atoms can
therefore be described as being radioactive. N. Campbell,
who made this interesting discovery, has continued his
researches on the feeble activity of substances and has
investigated what are termed the *-rays — rays which are
too feeble to ionise a gas and render it capable of con-
ducting electricity. The energy in ergs necessary to ionise
an atom is 4-2 X10"11; hence if the velocity of the
electrically charged particle which collides with the atom is
less than \/4'2 X 10 ", i.e., 3-6
im
second, where m (the mass of the electron) is equal to
X 10" centimetres per
6-5 X 10'i'i (the mass of the electron bears the same ratio
to a grain of wheat as the latter does to the whole mass
of the earth), the electron will not be able to ionise the
atom, and can only be detected by the charge it carries and
can give up to a conducting body. The velocity of such
8-rays have been measured and are of the order 3 X 10" centi-
metres per second, or smaller than the velocity necessary to
ionise an atom of a gas through which they pass.
Now sodium is in the group of elements which are similar
to potassium and rubidium, but no radiations are detectable
from it, neither does lithium give any measurable radiation.
It is curious that there should be these two elements, potassium
and rubidium — more or less light atoms as compared with the
heavy, unstable, radioactive elements such as uranium, radium,
and thorium — which show radioactivity and stand alone in
this respect. Such a fact raises the question whether most
elements do not emit characteristic radiations spontaneously
to a slight extent, but that the radiations are moving too
slowly, and the radioactive changes are proceeding too slowly,
both for the rays to be detected by their ionisation or for the
rays to be detected by the sum of their individual charges.
Some evidence for the radioactivity of sodium has been
brought forward by F. C. Brown in Le Radium for October,
1912. Although no measurable radiation is emitted by it, yet
from certain geological considerations there seems to be some
reason for the view. Joly has calculated the age of the earth
from the salinity of the ocean and the amount of salt carried
down to it by the rivers. The value is seventy million years.
However, from the amount of helium or of uranium in rocks
a measure of the age of the earth is also obtained, and this
makes the figure four hundred and twenty million years.
Consequently, if the latter value is correct, there is too little
salt in the ocean or too much carried down at the present
time by rivers ; if sodium was a member of a radioactive
series of elements there would be too little sodium in the
ocean and too much in the rivers, and in support of the actual
fact the proportion of sodium to chlorine in the rivers would
be such that the sodium would be in excess, whereas in the
sea the reverse would be the case.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A.
BREEDING LEECHES.— M. Moshin Khan gives an
interesting account of the breeding of leeches in the United
Provinces of India. It is the occupation of a class of people
called "Chohra." In April or May selected leeches are put
in earthen pots with " hair-cleaning clay " and a little water,
and the pots are put out of reach of all disturbances; for
the leeches are very sensitive when laying their cocoons.
When these are formed and have hardened, they are picked
up and put into closed cups of clay, which are changed every
alternate day for a fortnight. Then the breeders help the
young leeches out by breaking the shells. Each cocoon con-
tains five or six young ones. The young leeches are reared
in fresh water, and the breeder gives them meals from his
own body. Those that are sold for medical purposes are said
to lose their power of breeding ; so special " seed leeches "
are put aside. A leech stops sucking at once if there is any
pus mixed with the blood of the patient. The Chohra cleans
a gorged leech by puncturing it dorsally near the head and
pressing the blood out from the tail forwards.
AN INSECT PROTECTED BY ITS MEALS. — Dr.
A. Ch. Hollande, of Nancy, reports a very interesting case
of protective coloration. The flower-buds of one of the
mountain mulleins, Verbascum nigrum, are pierced in
autumn by the larva of a Curculionid beetle called Cionus
olens, which eats the violet hairs of the stamens. The violet
vegetable pigment (anthocyan) eaten by the grub passes
down the food-canal and, as usual, into the blood (in
some uncoloured form). It is carried to the fatty bodies
and accumulates there in numberless granulations, again of
276
KNOWLEDGE.
July, 1913.
a violet colour. The colour, shining through the brownish
integument, makes the grub most effectively harmonious with
the colour of the stamens amid which it works.
relaxation of the muscles mentioned above and — in Dioduns
and Tetrodons, at least — by the action of the ventral body
muscles, which are adapted to this purpose.
DEATH-FEIGNING IN I N SECTS. — This very
interesting reaction has been carefully studied by Professors
H. H. P. Severin and H. C. Severin with especial reference to
Belostoma and Nepa, two water-bugs. The death-feigning
positions are characteristic and definite, unlike those of the
dead insects. The average duration of the " feint " in
Belostoma was eight hours, and it is proved that the length
is affected considerably by the external conditions of drought
and illumination. The death-feint continues even when the
head of Belostoma is cut off, and decapitated specimens will
often swim freely after arousing from the feint. Both the
water-bugs studied are very sensitive to contact stimuli, and
in both species there is a marked propensity to cling together
and form clusters. The investigators do not think that there
is any conscious effort to deceive enemies through the death-
feigning. The act is non-intelligent and wholly instinctive.
FECUNDITY OF THE PO M AC E-F L Y — In some
Lepidoptera the reproductivity of the adult female depends
wholly on the nutritive conditions of the larva. In other cases
like the blow-fly, almost everything depends on the nutrition,
of the adult. In the pomace-fly, Drosophila ampelophila,
the nutritive conditions of any period have their effect on the
number of eggs produced and laid by the female fly. This
has been shown very clearly by Emile Guy6not. Immature
flies fed on potato become mature in seven to thirteen days
and lay an egg per diem ; but those fed on potato and
yeast become mature in four to five days at the most and lay
ten to fifteen eggs per diem to begin with, and twenty to
twenty-five later on. Mature females fed on yeast while
immature, but afterwards placed on potato diet, begin
to lay a day after their emergence, and they exhaust
themselves towards the end of the third day, thereafter pro-
ducing only one or two in a day. But their sisters, kept on
potato and yeast, continue producing a regular twenty to
twenty-seven eggs every day. Thus the influence of nutrition
on fecundity is made very clear.
CAVE SPIDERS. — Louis Fage has made a study of a
family of spiders, Leptonetidae, whose members are almost all
restricted to caves and grottos. There are some interesting
features. Thus it is not usual to find more than one species in
one cave, as if there were some intolerance of strangers in the
darkness. The webs spread among the stalactites and
roughnesses are very large and delicate. The spinners move
very slowly. If there is the least disturbance they either
quicken their pace or play possum with their limbs laid along
their body. In most spiders the males are found only at
certain seasons, but in the uniformity of the caves they are
found all the year round. The reproduction is not punctuated.
In the few cases where the eggs are known, the interesting
feature is that each cocoon contains very few, but these are
large. In some cases there are only two eggs ; in Telema
tenella there is only one in each cocoon. It is two-fifths of
a millimetre in diameter and the whole spider is only about a
millimetre. The adaptation here is that the young spider is
vigorous when hatched. It has had the advantage of a big
legacy of yolk.
INFLATION IN FISHES.— For a very long time it has
been known that many globe-fishes and their relatives have
the power of inflating themselves and floating on the surface.
Nils Rosen has been studying the mechanism of the inflation.
It is the air-sac that is filled — by swallowing movements. The
air is kept in by means of circular muscles in the wall of the
gullet and by a valve, or by means of a special closing muscle.
As a result, the body is like a football, and if there are spines
they stand out. The Diodons turn upside down and are
driven about on the surface of the sea by waves and currents.
It is a protective adaptation. The air-sac is emptied by the
GIZZARD OF BEETLES AND ORTHOPTERA.— It has
been too hastily assumed that the gizzard of insects, like the
water-beetle and the cricket, functions as a mill for grinding
up hard parts. Willy Ramme finds that it is mainly an organ
which allows some of the digestive juice of the mid-gut to
pass through into the crop, and which works up a sort of mash
of food and digestive juice. In all the insects studied the
digestive juice of the mid-gut was found in the gizzard (or
proventriculus) and in the crop. In Dytiscus the indigestible
parts, e.g., chitinous fragments, are kept back by the proven-
triculus and passed out again. In Orthoptera the indigestible
debris passes on through the intestine.
FUNGUS GROWING ON HAIR OF ECHIDNA.—
Karl Toldt reports the occurrence of an entirely new hair-
fungus which he found spreading its hyphae over and in the
cortical substance of the bristle-like hairs of Zaglossus
(Proechidna) bruijni from New Guinea. He suggests that
an examination of the hairs of the rarer mammals would
reveal the existence of some new and interesting Fungi.
HOW MUCH DOES A STARFISH SEE ?— At the end
of each arm in the common starfish there is a little red eye.
It is sheltered at the base of the terminal tube-foot, which has
become altogether sensory. The eye or eye-cushion shows
numerous little cups, each closed by a lens, lined by red rod-
like sensory cells, clothed externally by supporting cells, and
containing a transparent watery substance. Hellmuth
Plessner has recently made a number of experiments at
Heligoland in order to discover how much a starfish sees with
these " eyes," or eye-spots. The answer is: Not very much.
It does not form an image nor does it perceive a moving
object. But it has considerable sensitiveness in distinguishing
different degrees of light and shade. Even the skin of the
starfish is responsive to differences of illumination in the
immediate vicinity, but by means of its " eyes " the starfish
becomes aware of distant illumination that differs, either
positively or negatively, from that of the immediately
surrounding area.
FERTILISATION AND CONJ UGATION— When an
egg is fertilised there is an intimate and orderly union of the
nuclear elements of the egg-cell with those of the sperm-cell.
The number of chromosomes in each has been reduced during
the ripening process to half the number which is normal for
the species in question. Thus in fertilisation there is a
restoration of the normal number. It must also be admitted
that the spermatozoon brings with it an extremely minute
quantity of cytoplasm, which probably has some significance.
It is also well known that the spermatozoon introduces into
the egg-cell a centrosome, which divides into two and plays an
important role in the subsequent segmentation. The fertilising
spermatozoon keeps the egg from dying, as in all ordinary
circumstances it would otherwise do, and gives it some
initiative to development. In certain cases (of artificial
parthenogenesis) this part of the sperm's role can be replaced
by chemical or physical stimulus. But the other main role —
the mingling of two inheritances — is something quite apart
and more distinctively vital. Now it is interesting to find that
the careful experiments made by Professor H. S. Jennings on
conjugation in Paramoecium, the slipper-animalcule, all point
to the conclusion that conjugation does not effect any
rejuvenescence, its meaning being rather to secure biparental
inheritance, which often means variation. When the conditions
of life are untoward, conjugation is apt to occur, and it may
be followed by new combinations of qualities, some of which
are suited to the altered conditions of life. In those infusorians
conjugation implies a loss of vigour, but it promotes variations
some of which pay by securing survival.
REVIEWS.
ASTRONOMY.
Daytime and Evening Exercises in Astronomy.— By S. F.
Whiting, Sc.D. 104 pages. 26 illustrations. 7-T-iuX5-in.
(Ginn & Co. Price 3/6.)
This book is written for schools and colleges. The aim of
the authoress is to encourage and direct the teaching of
astronomy during the daytime (and night also) instead
of waiting for night instruction only. The method proposed
is to make practical acquaintance during the daytime with
many objects and branches of astronomical work, by means
of the study of models, globes, photographs, and other
apparatus, as set out in forty-five exercises. She has certainly
succeeded in putting a good deal of facts and questions into
these hundred pages ; but the book is primarily an aid to study
and work, and should be useful to teachers. If the book is
intended to be used here we think that, in another edition,
the articles mentioned on pages xi-xiv should not be re-
stricted solely to U.S.A. goods ; but, as equally good apparatus
and books are known and can be readily obtained in this
country, we suggest that these be given as alternatives ; many
of the names now given are quite unknown here. We would
further suggest some considerable reduction in the price.
The Index is very meagre and of little use : we looked for six
important items given in the book — four were not in the index.
F. A. B.
Annates de VObservatoire Royal de Belgiquc. — Physique
du Globe. Tome V., Fasc. III. 197-308 pages.
12J-in.X9j-in.
(Hayez, Bruxelles.)
This is a continuation of a long series of observations made
at the Belgian National Observatory at Uccle. The present
part contains the Hourly Magnetic Observations made at Uccle
in 1911 and their discussion by A. Hermant, seventy pages
and two plates ; Observations of Atmospheric Electricity in
1910 and 1911 and their discussion by A. Hermant, twenty-
five pages and four plates ; and the Temperature of the Sun
(i.e., the Earth) at different depths in 1911. From this last
section it may be seen that thermometers placed at depths of
0ra-l, 0m-2, 0m-3, 0m-6, lm-0, ln,-25 and l»-50 all record
the (mean) maximum temperatures in August, that at one
and a half metres being nearly the same in September ; while
the (mean) minimum temperatures occur in January for the
first four depths, at one yard the retardation or greater
deviation from the external air temperature becomes pro-
nounced, and the (mean) minimum is not reached until the
month of February ; the mean temperatures at all these
depths in March and September are very similar : the range
is within half and one degree (centigrade) respectively. But
we think the means for such periods as thirty days are much too
long and mask interesting facts.
F. A. B.
L'Astronomie : Observations, Tlieorie et Vulgarisation
Generate. — Par M. Moye. 396 pages. 4 plates.
43 figures. 7i-iu.X5-in.
(Paris : O. Doin et Fils. Price 5 francs.)
This is one of an extensive series called " Encyclopedic
Scientifique," published under the direction of Dr. Toulouse,
Directeur de Laboratoire a l'Ecole des Hautes-Etudes.
There is a short account or preface of six pages on the
" Bibliotheque d'Astronomie et Physique Celeste," by J.
Mascart (Director of the Lyons Observatory, who is to be the
astronomical editor of the series), in which there is a
discussion of the influence of various other sciences upon
astronomical knowledge, the reasons given for these books,
and the lines upon which they will be written. It is intended
to publish twenty-nine volumes upon astronomical subjects, of
which this volume by M. Moye is No. 1 ; there are three
others already published. The series is therefore a composite
one so far as concerns authorship, and it is intended thai
each volume shall contain about three hundred and fifty to
four hundred pages, with illustrations, in cloth, and be sold
separately at five francs.
The spirit in which the book is written may be given in the
editor's own words: — " Une notion prevaut pourtant le
caractere mystique, ardu et rebartif, de la science astronomique,
science reservee aux plus savants des savants ct dont la
moindre teinture semble donner a ses adeptes figure de
profonds techniciens. Au risque de perdre notre aureole,
nous avons au contraire essaye de demontrer la facilite avec
laquelle on peut mettre l'astronomie a la portee de tous ceux
qui veulent en apprecier les philosophiques jouissances."
The book is not a text book or handbook replete with
references, authorities, quotations, formulae, calculations, or
tables of figures ; nor is it quite of the scrappy popular form,
with speculations frequently bubbling out, appealing to the
senses. It takes its place as an introductory book to general
astronomy, and is just suited to young folks at high schools,
in their Continental sense ; for a university course it is too
popular and elementary. Most of the very numerous features
and facts in astronomy are referred to in a pleasant reading
and concise form. The type and figures are not too fine,
a frequent fault in French books ; the paper is poor. We
still notice the persistence of the use of French words for the
constellations. When will the French astronomers come into
line with the rest of the world and use the Latin designation ?
At the end there is a useful list of books consulted ; also an
index, which is very poor and incomplete. On page 277 the
author erroneously attributes the discovery of the crape-ring
to Bond and Dawes, and not to Galle ; and the date given,
1858, should be 1850. Galle's observation of the crape-ring
was made and published in 1838. FAB
CHEMISTRY.
Gas Analysis.— By Dr. Hartwig Franzen. Translated
from the German by F. Cali.an, M.Sc, Ph.D. 120 pages.
30 illustrations. 7j-in. X4j-in.
(Blackie & Son. Price 2/6 net.)
This little book should be found of great use as an intro-
duction to the larger works on gas analysis. Little knowledge
of the subject is assumed, and the directions for using all the
more simple forms of apparatus are sufficiently full and clear
for any beginner to follow, while excellent diagrams are
provided where necessary. The book is divided into two
sections, the first of which gives the methods of analysing the
common gases, while the second contains some of the
principal applications of gas analysis in the examination of
inorganic substances. By the way, the title of this section —
" Volumetric Gas Analysis " — is somewhat misleading. Tables
of the chief physical data required in gas analysis are appended,
but it is a drawback to an otherwise excellent book that no
index is given, and that the reader has to search through the
list of exercises for what he requires.
C. A. M.
Qualitative Determination of Organic Compounds. — By
J. W. Shepherd, B.Sc. (Lond.). 348 pages. 20 illustrations.
7-in.X5-in.
(W. B. Clivc. Price 6/6.)
A successful attempt is made in this book to systematise
the analysis of organic compounds upon similar lines to those
followed in the examination of inorganic substances. The
arrangement is distinctly novel and gives a clearer view of
the principles underlying organic analysis than any other
book with which we are acquainted. The first part deals
with the characteristic reactions of the different groups of
organic compounds, while in the second part the reactions are
classified and illustrated by typical examples drawn from the
different groups. The class to which a given substance
belongs having been discovered by systematic tests, the
substance may then be identified by its physical properties,
and for this purpose a good tabular index is provided.
277
278
KNOWLEDGE.
July, 1913.
Enough has been said to show the value of the book, not
only as an aid to examination, but also as a practical guide to
the student of organic chemistry. It is of necessity concise,
but it suffers in places from too much condensation, and this
is particularly noticeable in the section on Enzymes. In this
connection we notice that the author alludes to the coagulation
of blood as a fermentative process — an hypothesis which lacks
confirmation. The book would gain much if a section were
added on the qualitative analyses of dyestuffs upon the same
lines as those devised for the substances dealt with in the
other sections. „ . ,,
C. A. M.
The Atmosphere. — By A. J. Berry, M.A. (Cambridge
Manuals of Science and Literature.)
146 pages. 5 illustrations. 6i-in. X 5-in.
(The Cambridge University Press. Price 1/- net.)
The first impression after reading this little book is a feeling
of wonder how so excellent an account of the scientific
investigation of the atmosphere can be produced at so low a
price. The subject is treated purely from the chemical and
physical standpoint, and omits nothing of importance from
the days of Galileo to the present time. Separate chapters
are given to liquid air, radioactivity, the inert gases, and so on,
and there is a most interesting outline of the views and
speculations upon the probable composition of the atmo-
sphere in prehistoric times. Every page of the book is read-
able, and all points in dispute are stated fairly and without
bias. Portraits of Boyle, Priestley, and other early chemists
add to the interest, and there is a good bibliography and
index. In short, this is a model of what a popular scientific
book should be. _ . ,,
C. A. M.
One Hundred Simple and Exact Mathematical Proofs that
the Valencies of Carbon are Unequal. — By Hawkswork
Collins, B.A. (Cantab.). 110 pages. 8{-in.X 5i-in.
(Morton & Burt. Price 7/6 net.)
This volume is a sequel to the author's " The Relative
Volumes of the Atoms of Carbon, Hydrogen, and Oxygen
when in Combination," reviewed in "Knowledge" for
January, 1912. In it Mr. Collins shows how his method of
calculating molecular volumes may be extended to bodies
containing the halogen elements. So far as the results go the
atomic volumes of chlorine, bromine, and iodine in combination
with carbon are constant, being 23-01, 27, and 32-75 respect-
ively, whilst carbon, hydrogen, and oxygen have the same
values as before. The calculated values are in extraordinarily
good agreement with the experimental results of various
investigators, as was also the case in the former volume. In
view of this fact it is difficult to understand why Mr. Collins's
calculations do not receive greater attention from physical
chemists. His books are certainly worthy of this, whatever
views may be held concerning his theory of valency. As I
mentioned in the former review, Mr. Collins explains the fact
that hydrogen may have, according to the configuration of the
molecule, any one of four different values, by the theory that
the valencies of carbon are unequal. No doubt this would
explain it; but more than one alternative hypothesis is
possible ; and so this peculiarity in the calculated atomic
volume of hydrogen cannot be regarded as proving the
inequality of the carbon valencies. Further calculations
dealing with the molecular volumes of compounds containing
other elements are promised by Mr. Collins, and will no
doubt be awaited with interest by those who can value
calculations of this sort, and can appreciate the labour involved
in making them.
H. S. Redgrove.
ECONOMICS.
The Economics of Everyday Life. — A First Book of
Economic Study. By T. H. Penson, M.A. Part I.
176 pages. 48 tables and diagrams. 7$-in. X 5T-in.
(The Cambridge University Press. Price 3/- net.)
This work forms an admirable introduction to the science of
economics, and should meet the requirements of both the
general reader and the student who is just commencing a study
of the subject. The author's language is clear and simple ; he
is careful to give accurate and precise definitions to the terms
he employs ("wealth" and "labour" may be noted as
particular instances) ; and the frequent use of diagrams aids
greatly in enforcing the meaning of the text. Part I of the
work is divided into four books, dealing respectively with
introductory matters, production, exchange, and distribution.
Part II will deal with consumption, taxation, and trade unions
and cooperative societies.
A few points call for criticism. Mr. Penson explains the
construction of demand and supply curves, but he omits to
point out that if both curves are drawn to the same axes, the
market price ot the commodity dealt with (under the simple
conditions considered) is given at the point where the curves
intersect : this would probably not be obvious to readers
unacquainted with graphic algebra. In dealing with the
division of labour Mr. Penson notes both the advantages and
the disadvantages, but, whilst insisting on the former, unduly
depreciates the latter. Up to a certain point (i.e., into trades
and professions) the advantages are immense and the dis-
advantages very slight. But when division is carried to the
extent of incomplete processes, the gain to the community (or,
rather, to certain members of it) is, I suggest, outweighed by
the loss to those who are engaged in carrying out such
incomplete processes. It is thus that the factory system arises
with its many evils, especially the non-ownership by the work-
men of the tools of his trade, which largely destroys his liberty
and tends to make him the slave of the capitalist. Moreover,
the happiness of a community depends, not only upon its
wealth (i.e., upon what it possesses), but upon what it does;
and it cannot be denied that the carrying-out of incomplete
processes is soul-destroying work, though such considerations,
perhaps, belong to ethics rather than economics.
In enumerating the advantages of the large retail store over
the small business Mr. Penson says that " the large scale
tends to the accumulation of large amounts of capital in few
hands, and thus to the amassing of large fortunes " (page 77).
I cannot in the least understand in what sense this can be
held to be a genuine " advantage."
In concluding the volume Mr. Penson writes : " Whether
or not the existing system of distribution satisfies the claims
of justice or achieves the best social results is quite outside
the scope of the present work. In dealing with this question
as with others the aim has been to point out and to explain
things of everyday occurrence, to illustrate and to arouse
interest in the economics of everyday life." That, of course,
is the right attitude to take in an introductory work, in which
economics must be treated as a natural, and not as a normative,
science. Normative economics must come afterwards ; but
from the first, I think, we must be impressed with the fact
that, whilst the skill and ability of the workman or organiser
are inseparable from the man himself, capital is separable from
the capitalist ; hence that, whilst the workman and the organiser
are of value to the community, and should be remunerated for
their services, the capitalist is not only useless, but acts as a
clog on the free flow of monev. no n
B H. S. Redgrove.
ETHICS.
The Faith of all Sensible People. — By David Alec
Wilson. 124 pages. 6j-in. X4-in.
(Methuen & Co. Price 2/6 net.)
The title of this book, and the claim made for it that the
title is justified, strike one as somewhat pretentious, and the
author's style savours of dogmatism. But the book contains
a good many sound common-sense maxims on a variety of
topics, which show the predominant influence of Confucius.
The writer believes in evolution, but rejects the theory of
natural selection as unproven, though he offers no alternative
thereto. In passing, I might note that the acceptance of
natural selection as a scientific law by no means involves the
acceptance of the materialistic metaphysics which frequently
go along with it. Mr. Wilson has a keen dislike of transcen-
dental metaphysics, and he asserts that we do and can know
nothing of a life after death, if such there be. This, of course,
July, 1913.
KNOWLEDGE.
279
is sheer dogmatism. Experimental psychology has not yet
said the last word on the subject, nor is it scientific to reject,
without examination, the testimony of the religious conscious-
ness. When, however, Mr. Wilson discourses on the value of
knowledge, of perseverance and hard work, and on the
advantages of the married state, most readers will agree with
him. He explains that his object in writing the book was " to
distil knowledge from current speculation" and to " show to
the man in the street in plain words that the materialism so
widely believed is not science but pseudo-science." But
though I can fully sympathise with this object, I do not think
it has been accomplished in " The Faith of all Sensible
PeopIe-" H. S. REDGROVE.
MATHEMATICS.
The Nature of Mathematics. — By P. E. B.Jourdain, M.A.
92 pages. 6j-in. X4j-in.
(T. C. & E. C. Jack. Price 6d. net.)
This is a volume in the series entitled " The People's
Books." Mr. Jourdain does well to indicate the practical
value of mathematics and in emphasising the importance
as concerns the history of mathematics of Mach's view that
" science is dominated by the principle of the economy of
thought." But from the standpoint of the general reader the
book cannot be regarded as satisfactory. In the first place
there are no diagrams to assist him in understanding the text.
Moreover, the explanations, notably in the case of logarithms
and " imaginary " quantities, are wholly inadequate to his
needs. Dealing with the latter subject, the author says, " If
we are given the equation *"— 1 = 0, its solutions are evidently
x = + l,or#= — l,for the square roots of 4- 1 are + 1 and— 1."
He has not explained the multiplication of negative quantities,
and so to the non-mathematical reader the " evidently " will
come as a surprise. There is much else in the book of a
similar nature. Of course, in so small a compass it is
impossible to deal with the vast subject of mathematics
adequately, but I think much of the space filled with talk
about the ''logical basis of mathematics" might have been
better occupied with something about modern non- Euclidean
geometry, and, if possible, vector-analysis as well. Mr.
Jourdain distinguishes between mathematics and our know-
ledge of mathematics, and I gather that when he speaks of
mathematics as having a purely logical basis he is denying
that it is an empirical science. Mathematics, no doubt,
makes larger use of deduction than any other science, but
like all other sciences it is inductive at the basis. It is
experience, not logic, that enables us to assert that 1 + 1=2.
H. S. Redgrove.
The "Method" of Archimedes, recently discovered by
Heiberg. (A Supplement to "The Works of Archimedes,"
1897.) Edited by Sir Thomas L. Heath, K.C.B., Sc.D.,
F.R.S. 51 pages. 15 figures. 8i-in. X 5^-in.
(The Cambridge University Press. Price, 2/6 net.)
Heiberg's most valuable find is of the greatest value to
those who are interested in the history of mathematics ; that
portion of it consisting of a work hitherto supposed to have been
irretrievably lost is here presented in a convenient English
dress and in modernised terminology. The Greek geometers,
in their formal treatises, present the subject matter in a purely
logical form, giving no hints as to the methods they employed
in making their discoveries. The " Method " of the great
Archimedes is, however, not a formal treatise, but a letter
to a student ; and in it he lays bare the manner in which he
discovered a number of propositions concerning the areas,
volumes, and centres of gravity of certain figures. The two
chief propositions concern the volumes of two solids with one
or more curved surfaces, which can be expressed exactly in
terms of rectilinear solids. The method of discovery is a
peculiarly interesting and ingenious one, miking use of the
mechanical concepts of moments and equilibrium, for which
reason Archimedes did not regard it as supplying rigid proofs
of the propositions discovered by its aid. He therefore
supplied what he regarded as sufficiently rigid proofs of the
propositions, partly here and partly in other works, though
nowadays the mechanical proofs would be quite rightly
regarded as sufficiently rigid. It is interesting to note that, in
one case at least (namely, in the mensuration of the sphere),
the order of discovery is not that of logical development ; a
fact which may very well be advanced against the once
common idea that the best order of presentation in the
teaching of geometry is the logical one. Students of the
history of mathematics are under a large debt of gratitude to
Sir Thomas Heath for this most valuable translation.
H. S. Redgrove.
ORNITHOLOGY.
British Birds' Nests : How, where and when to find and
identify them. — By Richard Kearton, F.Z.S., F.R.P.S.
518 pages. With many plates and illustrations. 9 .J -in. X6-in.
(Cassell & Co. Price 14/- net.)
Mr. Kearton's book is really a new edition of his " British
Birds' Nests," with the addition of the best pictures that were
published in another of his volumes, entitled, " Our Rarer
British Breeding Birds," with others which have been more
recently secured. A feature of the present book is the
arrangement by which it is easy to find particulars of the
nesting sites and materials as well as the eggs of many of our
British Birds. The coloured plates of the Lapwing's nest and
eggs, as well as that of the Tree Pipit's nest, are exceedingly-
good ; and the figures of eggs reproduced by the three-colour
process from actual specimens adds greatly to the usefulness
of the work. It is evident that many photographs of the birds,
especially those of the more timid ones, such as the Water
Rail, must have been a great trouble to secure ; and among
the interesting points incidentally mentioned is one concerning
Rooks which built on chimney-pots. As a book of pictorial
records Mr. Kearton's " British Birds' Nests " is most
charming, and as a book of reference is of considerable merit.
G. K. W.
PSYCHOLOGY.
Psychology. — By Henry J. Watt, M.A., Ph.D., D.Phil.
90 pages. 8 figures. 6J-in. X4-S-in.
(T. C. & E. C. Jack. Price 6d. net.)
This is a volume in the series entitled " The People's Books."
It is an interesting little introduction to the study of
psychology, written upon somewhat different lines from that
of most elementary text books on the subject, being less
formal and schematic. Its condensed style, free use of
technical terms (the meanings of which are not always
explained), and the emphasis put upon the as-yet-unsolved
problems of psychology cannot do otherwise than make it a
somewhat " difficult " book for the general reader.
In dealing with the question of the empirical distinction
between sensation and imagery, Dr. Watt points out that the
mere degree of intensity does not supply an adequate basis of
distinction. He adds : " The distinction of sensation and
imagery must therefore depend upon our ability to say
whether an experience has come about through impression
from a real object or not. This is often expressed by saying
that in dreams we take our imaginations for reality, because
we have no reality by us to compare with them." This begs
the question at issue; for what this question asks is: How
can we distinguish between reality and imagination, or, rather
(so as not to perpetuate the common misuse of the term
"reality"), how can we distinguish objective from subject
reality ? I think that Berkeley adequately answered this
question to the effect that sensations occur in definite orders
and series (" laws of nature ") lying without the control of our
will, whereas imagery occurs, to a large extent, in what order
we please.
There is a short but telling criticism of the Langc-James
theory of the emotions in the book, and Dr. Watt well con-
cludes by insisting on "that magnificent jewel that delights
the eyes of all men and never wearies — the reality of effort."
H. S. Redgrove.
280
KNOWLEDGE.
July, 1913.
ZOOLOGY.
A Bibliography of the Tunicata, 1469-1910.— By John
Hopkinson, F.L.S. 288 pages. 9-in.X 5i-in.
(Dulau & Co. Price 15/- net.)
When Mr. John Hopkinson was preparing for publication
Alder & Hancock's " British Tunicata " he compiled a
bibliography for his own use, bringing matters up to the
year 1870, and liter, after consultation with Canon Norman,
he decided to extend it to the year 1910. This has now been
printed and forms one of the volumes published by the
Kay Society for the year 1912. The care with which Mr.
Hopkinson works is well known, and though he has been
assailed with various difficulties he has produced a volume
which will be of very great assistance to students of the
Tunicata, while he has made up for any little deficiencies
due to the printing of the work in two parts by appending
an addenda of twenty-five pages. w ., .,,
The British Parasitic Copepoda. — By Thomas Scott,
LL.D., F.R.S., and Andrew Scott, A.L.S. Volume I.
Copepoda Parasitic on Fishes. 256 pages. 2 plates.
9-in.X 5j-in.
(Dulau & Co. Price 15/- net.)
This, the second of the volumes published by the Kay
Society to subscribers for the year 1912, consists of the text
of Messrs. Scott's work, with two plates. The bulk of the
plates will appear as a volume for 1913. The Kay Society
published in the years 1878-1880 a monograph of the British
Free and Semi-parasitic Copepoda, by Dr. G. S. Brady, and
from this those forms which were truly parasitic on fish were
expressly omitted. Dr. Brady suggested that they should be
dealt with in a separate volume, and Messrs. Scott have now
produced it. With very few exceptions recent specimens
have been examined and carefully dissected. The result is a
series of very careful descriptions, to which are added details
of the habitats. „. ,, ,,,
W. M. W.
NOTICES.
THE KOYAL INSTITUTION.— A General Meeting of the
members of the Royal Institution was held on the afternoon
of June 2nd, the Duke of Northumberland, President, in the
chair. Mr. L. K. Guthrie, Mr. G. W. Heath, and Mr. K.
Malcolm, were elected members. The Chairman reported the
death of the Right Hon. Lord Avebury, a member of the
Institution for sixty-four years, and a resolution of condolence
was passed.
SECOND-HAND PHYSICAL APPARATUS.— Messrs.
Newton & Company announce that owing to the great develop-
ment of their optical business they can find neither time nor
space for their Philosophical and Physical Apparatus
Department, and are therefore disposing of the whole of their
stock at a low valuation. A catalogue has been issued,
including demonstration apparatus in Electricity, Chemistry,
Pneumatics, Sound, and so on.
ADDITIONS TO THE -ZOOLOGICAL SOCIETY'S
MENAGERIE.— The number of additions to the Zoological
Society's menagerie during the month of May was two
hundred and sixty-eight, and among those which are new to
the collection are two White-bearded Gnus (Connochaetes
albojubatus) received in exchange, two Naked-tailed Mice
(Uromys bruijnii) from Dutch New Guiana, presented by
Mr. A. F. R. Wollaston, and a Chestnut-faced Barn Owl
(Strix castanops) from Tasmania, which was purchased.
THE EAST COAST. — The east coast affords an oppor-
tunity for good work in Natural History and Archaeology, and
we recommend to those who are thinking of spending their
holidays there, a little book entitled " On the East Coast," by
Percy Lindley, fully illustrated in half-tone and colour, which
has just been issued by the Great Eastern Railway Company,
and can be obtained gratis from the Superintendent of the
Line.
BOOKS ON BIRDS.— Ornithologists will be interested in a
catalogue which Messrs. John Wheldon & Company have just
issued containing more than fifteen hundred titles. Besides
general works dealing with the subject under geographical
headings, sections are devoted to migration, to game and
domestic birds, as well as to bird protection. No less than
eighteen editions of " The Natural History of Selborne," by
Gilbert White, are included under " Selborniana," with other
works relating to the great field naturalist.
A NEW CAMERA.— We have received an intimation that
in anticipation of the holiday season, to which the taking of
photographs adds a great charm, the Optical Works of
Messrs. Goerz are introducing a new " Tenax " camera. The
working of this is simplicity itself, and it has an accurately
graded shutter as well as all the movements required. Added
to this it is fitted with one of the world-famous Goerz lenses,
and the scientific worker who wants a camera will feel quite
happy in taking advantage of what has been done for his lay
brethren.
ENGLISH MICROSCOPES.— We have pleasure in calling
attention to Messrs. James Swift & Sons' catalogue of
Microscopes and Accessories. In runs into seventy pages
and contains figures and descriptions of the more important
of the well-known microscopes which this firm produces.
There are some pieces of apparatus of particular use in
certain cases that may be mentioned, such as the Stevenson
Binocular Microscope for delicate dissection; the simple cone
camera for attachment to the draw tube of the microscope,
and the stereoscopic photomicrographic attachment designed
by Professor Herbert Jackson, which gives perfect stereoscopic
photographs of suitable subjects under the microscope.
MACMILLAN'S NEW BOOKS.— The catalogue of new
books which has just been issued by Messrs. Macmillan contains
among the notes, some details of the life of Miss Octavia Hill,
and in the classified list of books recently issued we notice
several on Archaeology and Agriculture. Mayo's " Diseases of
Animals " has been increased in price from 6s. 6d. net to
8s. 6d. net, and "Franklin's Electric Lightning " from 10s. 6d.
to 12s. 6d. Volume XC of Nature, September, 1912-February,
1913, is now ready, price 15s. net.
NESTING BOXES. — The great benefits which many birds
confer on the agriculturist and the forester have long been
appreciated in foreign countries, and recently it was
pointed out in the press how the Thirlmere plantations had
been saved from the attacks of the larch saw-fly owing to the
provision of nesting sites by the Manchester Corporation. In
this connection it is interesting to chronicle that the Royal
Agricultural Society has specially invited the Selborne Society
to send a representative series of its very successful nesting
boxes to the Forestry Exhibition, which will be held in con-
nection with the Royal Show at Bristol from July 1st to the
5th.
THE EMU. — Messrs. Witherby & Co. have been
appointed European Agents for The Emu, the organ of the
Royal Australasian Ornithologists' Union, and copies of that
publication can now be obtained at 326, High Holborn.
THE NATIONAL PHYSICAL LABORATORY.— The
Annual Meeting of the General Board of the National
Physical Laboratory was held recently at the rooms of the
Royal Society, when the report and accounts for the year
1912 and the statement of work for 1913 were presented and
approved for transmission to the President and Council of the
Royal Society.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted bv Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
AUGUST, 1913.
THE STREAMLESS DOWNS AND THEIR DRY
VALLEYS.
By G. W. BULMAN, M.A., B.Sc.
One of the most striking things on the Chalk Downs
of the south of England is the absence of streams.
" We have no waters to delight
Our broad and brookless vales,
Only the dew-pond on the height
Unfed that never fails."
And the reason is obvious. The substratum of
chalk is so pervious that the rain sinks into the rock
at once, and none can run off to form streams.
Another feature of the Downs are the numerous dry
valleys, which look as if they had been carved by
water. We may call the coexistence of the two
features the puzzle of the physical geography of the
Downs. If there are no waters to cut them out, to
what do we owe " Our broad and brookless vales " ?
In the " Memoirs of the Geological Survey "
(" The Geology of the Country round Eastbourne ")
we find the following suggestion by Mr. Clement
Reid :—
" Such a feature in the pervious chalk cannot be
accounted for by any change in the amount of
rainfall ; it points to other conditions which have
now passed away. It is in all probability a relic of
the Glacial Epoch, which in these southern districts
did not lead to an accumulation of ice, but caused
the rocks to freeze to a great depth, thus rendering
them impervious to any rain that might fall in the
summer. During that period the chalk would be
cut into valleys in the same way as any impervious
rock, instead of immediately absorbing the heaviest
rain, as it does at the present day."
Any suggestions coming from so distinguished a
geologist as Mr. Clement Reid must be received
with due respect, but there seems to be more than
one fatal objection to this explanation. It assumes,
in the first place, that the porous chalk became
saturated with water to the surface, and was then
frozen hard. But if the rain sank into the chalk as
it does to-day this could never happen. Even after
the wettest season the line of saturation never rises
to near the surface.
In the second place, is there any ground for the
belief that during glaciation the ground would be
frozen to great depths ? As a matter of fact, in
glaciated regions to-day ice and snow seem to keep
the earth warm. For there always seems to be
water under the glacier and ice-sheet. Mr. Reid,
however, seems to suggest that the southern parts
of the country were not covered with ice or snow
during glaciation. But we cannot hypothesise a
sufficiently heavy snowfall in the north to produce
glaciation, and none or very little in the south. Nor
can we suppose there was a summer rainfall
sufficient to cut the valleys without admitting a
corresponding snowfall in the winter. Would not,
then, the Downs be covered with snow and the
ground thus kept from freezing ? And even if
summer began with a frozen ground, would it not
begin to melt simultaneously with the first rain ?
We further venture to think that if these dry
valleys in the chalk had been carved during the
glacial period they would now show signs of filling
up. For there must be some movement of material
into them from the higher ground at the sides, and
there has been time for some to be almost obliterated.
But instead of thus growing less they seem rather
to be still in course of formation.
We venture, therefore, to suggest as a tentative
hypothesis that our dry chalk valleys are the lines of
underground waters comparable to the Oueds of the
African deserts ; not as to origin, but in the fact
281
282
KNOWLEDGE.
August, 1913.
that they are underground rivers. The Oueds of the
Sahara are buried rivers, but to-day no rivers are to
be seen, only more or less fertile valleys in the desert
marking their courses. The rivers have been buried
by the drifting sand, but their waters still pass
along the old channels. In a different way we
suggest that the waters of the Downs have become
underground streams, which have made their own
now streamless vales. Suppose the line of such a
valley lies among the main dip, and that rolls in the
chalk cause minor dips on both sides towards this.
The rain sinking into the chalk will descend till it
reaches an impervious substratum. Then it will
soak on both sides towards the central lines of the
valley. Reaching this it will, along with what
reaches it directly from the surface, flow or soak
along the main dip. All the time it is dissolving
and carrying away the rock, and the surface
gradually sinks in, as it does in the formation of
swallow holes. Thus we suggest that the dry
valleys of the chalk are due to subsidence caused by
underground waters directed by the slopes of the
strata.
The action of the underground water would
be assisted in a small degree by that of the sur-
face. For when a channel was once formed the
rain water would tend to collect in the hollow in
the form of soaked soil or subsoil. Here, then, the
solvent action would be greater, and the making of
the valley hastened. The whole is a tentative
hypothesis only, but one that seems worthy of
careful consideration. And, apart from any inherent
probabilities in their respective suppositions, it
appears to possess this advantage over the glacial
hypothesis, that it views the valleys as still in the
making. Mr. Reid's explanation, on the other hand,
looks upon them as completed in the Glacial Epoch.
And we think that there is evidence that the denud-
ing forces are still at work, for otherwise would
they not show signs of filling up ? There must be
a certain amount of slipping and sliding and wash-
ing of matter into the valleys from the sloping sides
which would tend to obliterate them. But they do
not, as we have said, appear to be growing less.
It is possible, however, that some of these valleys
date back for their initiation to the time when the
chalk was covered by Tertiary deposits, sandstones,
clays, limestones, and so on. In these strata
streams might cut out valleys in the ordinary way.
When these rivers had got down to the chalk, their
beds would contain sufficient clay, and so on, to
prevent them altogether being absorbed. The chalk
itself might have become impregnated with clay to
a certain depth, and so have become impervious.
This might last long enough for the stream to cut
down the chalk to a certain extent. Finally, how-
ever, all clay and impervious chalk would be swept
away, and the rain sink directly into the ground as
it does to-day. But we need not suppose that the
river which cut the valley has actually gone. It
may, so to speak, have sunk into the ground, and be
still carrying on its work of excavation. Obviously,
at any rate, the water which normally runs off as
streams and rivers is in some fashion working its
way through the rocks below.
We may carry the idea of underground streams
and rivers a little further. The invisible waters of
the downs flow finally into a great subterranean
lake which lies in the rocks beneath the lower
valley of the Thames. There they are joined by a
similar set of streams from the chalk hills north of
London. For the chalk of the south of England
dips beneath the strata of the London basin, and
rises again to the north. The Tertiary rocks of the
London basin, in fact, lie in a syncline or trough of
the chalk, and in this the water collects. So a part
of the rain falling on the Downs finds its devious
way to the great subterranean reservoir over which
is built the Metropolis. When an artesian well is
sunk through the Tertiary beds and a part of the
chalk an abundant water supply gushes out. The
waters which should " delight our broad and brook-
less vales " go unseen to supply the deeper wells of
the city of London.
ADDITIONS TO THE ZOOLOGICAL SOCIETY'S MENAGERIE.
The registered additions to the Society's Menagerie during
the month of June were 295 in number. Of these 144 were
acquired by presentation, 35 by purchase, 56 were received on
deposit, 15 in exchange, and 45 were born in the Gardens.
The following may be specially mentioned : —
One Pudu Deer (Pudupudu), from Chili, and two Patagonian
Cavies (Dolichotis magellanicus), from Patagonia, presented
by Mr. Albert Pam, F.Z.S., on June 2nd.
Three Pumas (Felis concolor), born in the Menagerie on
June 13th.
Two Canadian Beavers (Castor canadensis), from Canada,
received in exchange on June 5th.
One Savanna Sparrow (Passerculus savannah), from
North-East America, new to the Collection, purchased on
June 18th.
One Ceylon Mynah (Acridotheres melanosternus), new
to the Collection, presented by Dr. Philip H. Bahr, F.Z.S., on
June 29th.
One Golden-fronted Woodpecker (Melanerpes flavifrons),
from Brazil, new to the Collection, purchased on June 5th.
One Calthrope's Parrakeet (Palaeornis calthropae) from
Ceylon, new to the Collection, deposited on June 29th.
One Condor (Sarcorhamphus gryphus), from Chili, pre-
sented by Mr. Albert Pam, F.Z.S., on June 2nd.
Two Crested Screamers [Chauna cristata), bred in the
Menagerie on June 19th.
Two Sun-Bitterns (Eurypyga helias), from South America,
purchased on June 16th.
One Kagu (Rhinochetus jubatus), from New Caledonia,
received in exchange on June 27th.
Two Spiny -tailed Skinks (Egernia depressa), from
Australia, new to the Collection, purchased on June 10th.
A collection of Snakes from Sierra Leone, including three
Sooty Snakes (Boodon fuliginosus), new to the Collection,
presented by Mr. Guy Ayhner, F.Z.S., on June 18th.
A collection of Snakes from India, including one Forsten's
Tree-Snake (Dipsas forstenii), new to the Collection, received
in Exchange on June 2nd.
Two Gopher Frogs (Rana aesopus), from North America,
new to the Collection, received in exchange on June 2nd.
THE HAIRS OF ANIMALS.
By C. AINSWORTH MITCHELL, B.A. (Oxon), F.I.C., and R. MORRIS PRIDEAUX, F.I.C.
The study of the hairs of animals has been singu-
larly neglected, notwithstanding the many questions
of scientific interest that it involves. With the
exception of silk and wool, which now have a fairly-
full literature of their own, little will be found in
textbooks about other animal fibres and the curious
differences in structure shown by the hairs of
different species of animals. In the present article,
therefore, we wish to give a general outline of the
nature of hair, together with some account of
observations that have been made by us and not
hitherto published.
In the popular view, wool and hair are usually
regarded as something quite distinct, but the
difference is one of degree rather than of kind.
Wool may be defined as a particular variety of hair
of fine texture characterised by having a more or
less curled form and a surface covered with scales
which tend to overlap each other. As a rule there
is no medulla.
This distinction between hair and wool is by no
means sharp, and it is not uncommon to find the
same animal producing both types of fibres. For
example, in trie hair of the goat there is a lower
layer of woolly fibres, and a similar mixture of the
two sorts of fibre may be observed in the coats of
certain breeds of dogs, such as the Bedlington
terrier (Figure 299).
In the case of the Siberian sheep the nature of
the hair varies with the seasons, the coat being of a
hairy type in the summer, but changing to wool in
the winter. The predominance of woolly fibres in
the coats of ordinary breeds of sheep is largely the
result of the animals having been kept for generations
under exceptional conditions, and of special breeding
to produce this result. When the ordinary domestic
sheep is allowed to run wild, it will in the course of
a generation or so produce a fleece containing a
large proportion of straight fibres.
The character of the scaling upon wool is an
important factor for distinguishing between the
products of different breeds. For example, in the
wool from the merino sheep, the scales go round the
fibre, so that the microscopic appearance suggests
that of a Malacca cane, with closely set joints (see
Figure 295), whereas in the wool from cross-bred
sheep the scales are smaller and cover only a small
section of the axis of the fibre (see Figure 296). In
healthy wool the scales cover the area of the fibre
completely, but in certain diseased conditions the
cortex will appear bare in patches. It is not
uncommon, however, to find in the wool of lambs
that have not yet been shorn numerous fibres from
the tips of which the scales have been completely
stripped by friction (see Figure 297).
The scales on the hair of animals are best
examined by oblique illumination by throwing the
iris diaphragm out of the optical axis of the instru-
ment. This causes the projecting edges of the
scales to catch the light in such a way that they
stand out clearly.
The number of scales on a given area varies
greatly. For example, Hanausek found that in one
millimetre length the number of scales showed the
following variations :—
Sheep's Wool (ordinary) 97
White Alpaca ...
... 90
„ ,, (merino).. 114
Brown „
... 150
„ „ (Saxony).. 121
Vicuna
... 100
Angora Wool 53
Camel's Hair ...
... 90
The cortex or surface beneath the scales frequently
shows longitudinal streaks, and in the coarser types
of hair a medulla or central canal may be present.
This medulla may be continuous along the length of
the fibre, or it may show interruptions in places, or
stop abruptly. It often shows cells of characteristic
form, while in other cases it is made up of granular
particles. It is best examined under the microscope,
with the iris diaphragm reduced to a small aperture.
Frequently it will be found that when both
woolly and hair-like fibres are produced by the
same animal, the former show no indications of a
medulla, whereas the latter have a pronounced
medulla. A good instance of this may be seen
in the hair of the Cashmere goat and in that
of some of the small American goats. In vicuna
fibres from Auchenia vicuna, fine woolly hairs with-
out medulla predominate, whereas in alpaca hair
from Auchenia paco most of the fibres are coarse
and show a medulla.
The wavy structure of woolly hairs, which is
most pronounced in the finest varieties of sheep's
wool, appears to be due to contractions, which are
caused by the cells upon the cortex being uneven.
In types of wool which approximate more nearly to
hair, as, for example, that of the Angora goat or
mohair, there is only a slight tendency' towards
curling.
Another point to which attention must be given
in differentiating the fibres of different species of
animals is the distribution of the pigment in the
cortex. In studying this feature under the micro-
scope as much light as possible should be transmitted
through the fibres. This will cause all signs of
283
284
KNOWLEDGE.
August, 1913.
medulla and scaling to disappear, but will render
the disposal of the pigment very distinct.
In the case of sheep's wool, fibres containing
black or brown pigment are relatively uncommon,
whereas in the hair of the camel and many other
animals, they are of frequent occurrence.
Arrangement of the pigment in dashes or lines, or
in a congeries of dots, is often characteristic of the
hairs of particular animals, as may be seen by
reference to the illustrations of the hairs of the
bears and some of the apes. The Himalayan
goat or serow produces hair (see Figure 298), which
may be taken as typical of the bristle type of fibres.
Among the hairs will be found some so heavily
charged with pigment that in places they are quite
opaque. Other bristles, however, of equally coarse
character contain but little pigment. In both these
types of fibres the medulla is very pronounced (A),
nearly down to the base, while in the dark-coloured
fibres the pigment extends nearly the length of the
hair (C). In some of the fibres of a less coarse
nature there is no medulla, and the scaling is less
pronounced.
From what has been said the general points to be
studied in examining the hairs of animals will be
readily understood, but it may be of interest to
amplify our remarks by reference to the fibres of
particular animals, and especially those of allied
species.
In the hair of the dog, as in the case of sheep's
wool, considerable differences will be found in the
fibres produced by different breeds, the wire-haired
dogs having hair of different type from the silky-
haired dogs. In the woolly hair of the Bedlington
terrier, to which allusion has already been made, the
scaling projects and no medulla is visible, so that
the general appearance of the fibre resembles the
wool of an Angora kid (see B, C, Figure 299). The
stoutest type of hairs (D) are of a bristly character
and show a pronounced medulla, while intermediate
between these extremes are fibres showing an inter-
rupted medulla, fine scaling, and faint longitudinal
markings.
It is interesting to note that the coat of the
native Australian dog, the dingo (see Figure 300),
has fibres of the three types and shows to an even
more pronounced degree an analogous cellular
structure of the medulla.
On the other hand, the few remaining hairs of
the Mexican hairless dog (see Figure 301) show a
very different structure. In the fibres without
medulla the surface is covered with fine scales,
resembling that upon the hairs of some of the
apes, while the other fibres have a very coarse
medulla which does not show the cellular structure
usually found in the hairs of ordinary breeds of dogs.
In the fur of the wolf (see Figure 302) the cellular
structure of the medulla is apparent in some of the
fibres, whereas in others there is a very broad con-
tinuous medulla. In the former the scaling causes
the edge of the hair to appear sharply serrated, while
in the latter the edge is nearly smooth and the
scaling very fine. The type of fibres marked A is
intermediate between these extremes.
Wide variations in structure are also shown by
the hairs of the African jackal (see Figure 303).
These include coarse black and white bristles, having
an opaque medulla (A) and ending in a fine point
(B), and fine woolly hairs which are well covered
with scales. In the latter the medulla, which in
places has a chain -like appearance, stops near the
apex, where the fine scaling resembles that of merino
wool.
Similarly, in the fur of the fox (see Figure 304)
the fibres contain a small proportion of bristles
having a w ide medulla which becomes intermittent
towards the tip, which ends acutely (C). Most of
the hairs, however, are soft and curl}-, with scales
projecting from the edges, and this, in conjunction
with the structure of the medulla, gives to the fibre
the appearance of a jointed chain.
Coming next to the cats it will be noticed that in
the fur of the domestic cat, the fibres end in a very
fine point, while the scaling is well marked, and all
show a medulla which here and there is interrupted.
In the full-grown animal the medulla may be wide
and show a reticulated structure (C, Figure 305),
but in the case of the kitten the hairs have pro-
jecting scales and a medulla made up of a series of
single cells.
It is interesting to note that the leopard shows
fibres of an analogous character, the medulla in
some being wide and continuous (see Figure 306),
while in others, which show fine scaling, it is inter-
mittent. Examples of the unicellular structure of
the medulla seen in the hair of the common kitten
may also be found.
Mention may also be made here of the so-called
sea-cat of Chili, which is valued for its fur. The
fibres are of the most variable type. On the fine
hairs the scales are very prominent but not plentiful,
and in some cases (C) project so much as to give
a feathery appearance to the hair. The fibres
terminate in a somewhat blunt point, and have
a medulla which ends near the base (see Figure 307).
The reticulated structure of the medulla which is
shown by some of the fibres of the cat is much more
pronounced in the hair of the brown rat (see
Figure 308). These are of the bristly type, with
scaling well marked towards the base, and end in an
abrupt point.
Examples of hairs from the fur of different species
of bears are shown in Figures 309-311.
In the fur of the Himalayan bear some of the fibres
are dark brown and very opaque, while others are
August, 1913.
Figure 295.
Merino Wool.
Figure 296.
Irish Wether.
KNOWLEDGE.
Figure 297.
Lamb's Wool.
L
Figure 298.
Himalayan Serow ? .
/• f
285
Figure 299.
Bedlington Terrier.
Figure 300.
Dingo Puppy.
Figure 301.
Mexican Hairless Dog.
Figure 302.
North American Wolf.
Figure 303.
African Jackal.
Figure 304.
Common Fox.
Li
Figure 305.
Cat.
Figure 306.
Nigerian Leopard.
I
[(
Figure 307.
Sea Cat.
HAIRS OF ANIMALS X 104.
286
I
KNOWLEDGE.
HAIRS OF ANIMALS X 104.
E2
August, 1913
Figure 308.
Brown Rat.
Figure 309.
Himalayan Bear.
Figure 310.
Russian Bear.
Figure 311.
Sloth Bear.
li
m
i
.
li
*
*. ■>
Figure 312.
Kangaroo.
Figure 313.
Rabbit.
Figure 314.
Sable Antelope.
Figure 315.
Human Hair.
Figure 316.
Young Chimpanzee.
teSpi*i.»»
Figure 317.
Old Chimpanzee.
J \J
Figure 318.
Orang Utan.
Figure 319. Figure 320. Figure 321.
Gibbon (hind foot). Human Hair (axillary). Hair of Negro.
August, 1913.
KNOWLEDGE.
287
paler and show well-marked scaling and an ill-defined
medulla.
The Russian bear also shows the two kinds of
fibres, but the medulla, when present, is much more
pronounced.
In the hairs of the sloth bear the medulla is usually
absent. The pigment is deposited in lines in the
same way as in the hair of the other bears, while in
the central portion of the fibre the scaling is close
and well marked.
Hairs of very distinctive types are shown by the
kangaroo (see Figure 312) and the rabbit (see
Figure 313), the structure of the medulla and the
scaling being very characteristic in each case.
A single example of the hair of the antelopes is
given (see Figure 314) which shows two portions
of a fibre from the coat of a Rhodesian sable
antelope. The hairs are long and coarse and show
a broad opaque medulla extending from the base
nearly to the tip (A). The scaling on the cortex is
fine but well defined.
There is no difficulty in distinguishing between
human hair and the hair of any of the lower animals,
but the numerous points of resemblance between the
hairs of allied species of animals suggested the
possibility that man's nearest relation among the
animals might also show analogous resemblances to
human hair.
Apart from its scientific interest, the point is of
practical importance, since it is frequently necessary
in forensic w^rk to ascertain whether a particular
hair belonged Lo a human being or to an animal.
To investigate this question we have made a study
of widely differing types of human hair, and have
compared them with the hair of some of the principal
species of anthropoid apes.
The hair shown in A, Figure 3 15, was taken from the
head of a newly-born female child, and it is remark-
able that the fibre has many more points of resem-
blance in common with the hair of some of the lower
animals such as the merino sheep, than are to be
found in adult human hair. Thus on the hair of the
young child (B) the scales are very scanty, while in
adult human hair they become more numerous and
more compressed. There is also a tendency towards
a jointed structure, which disappears in the hair of
the adult (see C, Figure 315).
In the hair of the young chimpanzee (see
Figure 316) it will be noticed that one of the fibres
(B) resembles the hair of the young human child,
with the exception that the scaling is less pronounced ;
but in the other fibre (A) there is a clear medulla.
Again, in the hair of the old chimpanzee (see
Figure 317) it will be seen that part of one of the
fibres, near the base, resembles adult human hair,
but that here, again, the scaling is less pronounced
than on human hair. In this hair, however, a
medulla interrupted in places will be found, while
at the top the disposal of the pigment differs from
that usually found in human hair.
The hair of the orang utan (see Figure 318)
and of the gibbon (see Figure 319) also shows
points of resemblance to human hair, but there are
also many distinguishing features.
A medulla is much more common in the hair of
the higher apes than in European human hair. In
a lecture to the Selborne Society it was stated by-
one of us (Mitchell) that apparently a medulla
was not formed in human hair.
Since then our investigations have led us to
modify this statement considerably.
It occurred to us that since the axillary hair in
man is probably a vestige of his former ancestry, it
was in such hair that a medulla would be most
likely to be found. This was confirmed by a
study of the hair from the human arm-pit (see
Figure 320). In some of these hairs there was a
narrow irregular medulla (A), with dots of pigment,
but no scaling visible, while others equally stout
showed no medulla, but were covered with fine
scaling which was well marked near the base.
The remarkable result of this examination led us
to examine the hair of a negro, in which it appeared
probable that the relationship between the hair of
man and the apes might be traced more closely than
in the case of European human hair. The result is
shown in Figure 321.
The fibres were coarse, and usually showed a
narrow medulla, which in some cases was continuous
throughout the whole length of the hair.
The pigmentation was so pronounced in some of
the fibres as almost to obscure the tract of the
medulla, while other hair contained a much smaller
amount of pigment. Apparently the amount of
pigment had no bearing upon the occurrence of a
medulla. In all the fibres the scaling was ill-defined.
A comparison of these hairs with the hair of
the apes, especially the orang utan, shows how
close are many of the resemblances. In fact,
it appears justifiable to conclude that the hair of the
negro resembles that of some of the higher apes
much more nearly than it does the hair of the
average European.
We intend to continue the study of this interest-
ing branch of our subject, and should be grateful if
any reader of " Knowledge " would forward to us
any authenticated specimens of hairs of out-of-the-
way races of mankind.
Note.— All the illustrations are drawn to the same scale of magnification (104 diameters).
CORRESPONDENCE.
MARS.
To the Editors of " Knowledge."
Sirs, — In your issue of June there appeared on the above
subject a letter, signed J. E. Maxwell, which contains so many
errors and misrepresentations that their complete refutation
seems to me necessary.
In the first place there is a confusion in the very purpose
of that paper, since its author chiefly disagrees with me on an
idea of mine which he himself adopts. It is stated in my
article, on pages 193-196, that although there are no straight
lines on Mars, yet this truth would not be accepted without
opposition, and that the astronomer of the future will sneer
at these wonders. Hence I made it quite clear that my
arguments and proofs had not yet secured public recognition,
and that, consequently, at present they are not established
truths. Yet the author of the letter in question, in his anxiety
to contradict, overlooks that he appropriates my idea by
proclaiming that my views " are not established truths." But
even otherwise considered, the argument has no bearing ; for
when an investigator is sure that he enunciates the truth, he
cannot but remain utterly indifferent to the acceptance, or
temporary non-acceptance, of his results by the public.
The correspondent in question next says that he has never
before seen it stated that " canals " appear " straight and not
curved at the edge of the disc." And yet canals are drawn
straight near the limb by Schiaparelli, Perrotin, Terby, Guiot,
Wilson, Cerulli, Lowell, Douglass, and others. Further,
from one of the numerous papers in which this peculiarity was
pointed out, I shall quote a passage in " Knowledge " for
1894, page 250, where we find that "the 'canals' when near
the edge of the disc are apt to be represented as much
straighter than they could possibly be." With ordinary care
and prudence such public display of unaquaintance with the
subject treated could easily have been avoided.
Another glaring oversight is the assertion that "no markings
. . . can be seen near the limb of Mars, owing obviously to
the planet's atmosphere." That this is just the reverse of
reality is proved by the photographs, which show all dark
markings quite as intense near the limb as near the centre of
the disc. The apparent character of the bright limb, due to
contrast with the dark sky, is naturally not even suspected
here.
There is nothing extraordinary in the fact that Mr. Denning
discovered the true nature of the minor detail on Mars with
a ten-inch, while Mr. Lowell failed to do so " with his twenty-
four-inch." For, to say nothing of the superior ability and
experience of the former of these two observers, the effective
difference between their telescopes is not the difference of
ten and twenty-four, as erroneously pointed out on pages
238, 239, but the difference between ten inches and thirteen
and a half inches, since this last is the usual aperture to
which the twenty-four-inch is stopped down on Mars.
The writer of the letter quoted next fails to understand the
effect of magnification of a planetary disc on the sharpness of
its markings. Yet nothing can be clearer. Inasmuch as the
fine lines flashing on Mars are usually flashing on a disc
having the apparent size of a sixpenny piece held at the
distance of two feet from the eye, they ought to be represented
quite sharp on such a small disc held at the above distance.
But on a three-inch drawing, seen at one foot, the sharpness
would cease, just as the sixpenny piece enlarged photographic-
ally to six inches would show nothing but very vague details.
Should further corroboration be needed on this point, it could
be found on the best photographs of Mars, which, while
revealing more delicate detail than any ever drawn prior to
1909, yet show all markings diffuse on a disc smaller than one
inch in diameter.
On page 239 doubt is cast on the fact that the narrow
straight lines on Mars are seen only by glimpses. Here,
again, we have a confusion of the straight fine lines with the
diffused streaks, held steadily. My experience, like that of
Terby and others, is that the lines are always flashing for a
small fraction of a second ; and as this was also Schiaparelli's
experience, I shall be excused if I accord a greater weight to
the Martian observations of Schiaparelli than to those of an
unknown amateur.
With regard to Figures 190 to 193, page 194, we are now
asked to believe that the structure of the planet was
geometrical and furrowed with straight lines on 1909,
September 18th; that it was natural and irregular, without
lines, two days later, on September 20th, and also on
October 5th ; and that it was again geometrical with straight
lines on November 3rd. The manifest impossibility of such
an assumption proves that my drawing, corroborated, as it is
by Professor Hale's wonderful photograph, shows Mars
practically as he is (so far as our present optical means go),
and that the rude sketches of Mr. Lowell and M. Jarry-
Desloges, which fail to reveal the coarser details, break down
altogether under the crucial and unanswerable test of photo-
graphic comparison. Behind the impersonal confirmation of
photography, I am awaiting all critics with a smile ; and the
overwhelming superiority of large telescopes, displayed every
day on double stars, and by the spurious satellite to Sirius
discovered at Mr. Lowell's observatory, thus receives an
additional, though useless, corroboration.
I granted some years ago, and still grant, that Flag-
staff may enjoy the finest atmospheric conditions for
astronomy. But as the aperture there is some thirteen and
a half inches, Mars is defined in Arizona as if he were from
two and a half to three times more distant than in the three
largest refractors of the world. This is the reason for which
a few seconds of perfect seeing at Yerkes, Lick, Meudon, or
Mount Wilson have done more for the recognition of the true
character of the Martian spots than the laborious canal
records of nine whole apparitions at Flagstaff. Does the
correspondent know that the areographer who drew more
straight lines on Mars than any other — Professor A. E.
Douglass— in a visit paid me in 1910, declared all the canals
which he was seeing for years with Professor Lowell's very
telescope at Flagstaff to be illusive.
Discussions on such a one-sided affair as the canal
question are, of course, useless. Yet the present letter, besides
refuting opposition, has also rendered clear the position of
the believers in the linear canals, which is : (a) that,
within certain limits, the more distant a heavenly body is
from the observer, the better he distinguishes the details of
its surface ; (b) that, within wide limits, the greater the
confusion of vision of an object, the sharper its perception ;
and (c) that the laws of perspective, on which our knowledge
of the universe stands, are wrong.
When the defenders of a theory are reduced to question
the truth of natural law for its support they merely betray
the rout of their reasoning.
E. M. ANTONIADI.
Paris.
HEN BIRDS WITH MALE PLUMAGE.
To the Editors of " Knowledge."
Sirs, — Regarding the statement by your correspondent (the
Director of Melbourne Zoological Gardens) that hen-pheasants
and so on, assume the plumage of the male bird under certain
conditions, it may interest your readers to know that when
visiting Folkestone Museum a few years ago I saw there a
stuffed specimen of a cockerel which a card near explained
had formerly worn hen plumage, and even laid eggs. The
bird had been the property of a farmer in the vicinity whose
name is attached to the card.
A. ATKINSON.
Harrogate.
288
SOME NOTES ON THE HISTORY AND SIGNIFICANCE
OF THE THEORY OF SPONTANEOUS GENERATION.
By H. STANLEY REDGROVE, B.Sc. (Lond.), F.C.S.
A belief in the spontaneous generation of such
forms of life as mice, maggots, lice, and other
vermin out of dirt and decayed organic matter
was at one time universally held, and was explicitly
taught by Aristotle (see the fifth book of his " History
of Animals"). The first work of importance to
throw doubt on this theory was done in 1668, when
the Italian Redi showed that no maggots were bred
in meat, if flies were prevented from laying their
eggs on it. In 1683, however, A. van Leeuwenhoek
discovered, by the aid of the microscrope, those
forms of life, invisible to the naked sight, that are
known as "bacteria." This discovery seemed to give
considerable support to the doctrine of spontaneous
generation, or abiogenesis (as it is now generally
called), it being found that, hosvever carefully bodies
of organic origin were screened from contami-
nation by outside sources, bacteria invariably made
their appearance in them. In the middle of the nine-
teenth century, however, Pasteur found that if the
bodies were first sterilised by heat and prevented
from coming in contact with any air other than that
which had also been sterilised, no bacteria were
developed : milk, for example, he found would
keep good for any period in these circumstances.
Pasteur's results are accepted by practically all
modern biologists and bacteriologists. Professor
Charlton Bastian,* however, has more recently
carried out numerous experiments with results
apparently altogether opposed to those of Pasteur.
Indeed, he states that he has obtained growths
of bacteria and torulae in inorganic saline solutions
containing sodium silicate or colloidal silica (prepara-
tions of mineral origin) which had been completely
sterilised by heat and preserved in hermetically
sealed tubes. It is evident that abiogenesis must
have taken place at some period of the world's
history, for certainly no life could have existed on
the earth when it was in a molten condition ; and if
one argues (as has been done) that life was first
conveyed to this earth by meteorites from other
planets, apart from the intrinsic difficulties of this
theory, it merely transfers the problem of the origin
of life to another planet without in any way simplify-
ing it. Given the right conditions, therefore, there
seems no valid reason why spontaneous genera-
tion should not take place now ; though it is, perhaps,
difficult to understand how organised forms of life,
such as bacteria, could be immediately produced
from inorganic matter; but, as Professor Bastian
indicates, the production of the bacteria and torulae
in his experiments may have been preceded by the
formation of ultra-microscopic specks of unorganised
life. Another question that may be asked in
connection with these experiments arises out of the
fact that protoplasm, which is the material basis of
all forms of life, contains carbon as one of its
essential elements. Must we assume that a trans-
mutation of the elements occurred in Professor
Bastian's experiments ? Or is it possible for silicon
to take the place of carbon in protoplasm ? However,
Professor Bastian's results have not met with general
acceptation. It is a pity that his experiments are
not repeated by other competent biologists ; some
degree of "certainty in the matter might then be
obtainable.
In 1905 Mr. Butler Burke thought he had
succeeded in obtaining living " cultures " by the
;,; In Professor Bastian's experiment very dilute solutions of sodium silicate containing either (i) a few drops of liquor
ferri pernitratis (ferric nitrate solution) or else (ii) a very small quantity of ammonium phosphate and phosphoric acid
were placed in sterilised glass tubes and hermetically sealed. They were then heated to temperatures varying from 115° C. to
145° C, and afterwards exposed to diffused sunlight. After several months they were opened, and the sediment formed
by the chemical reaction between the salts when the solutions were heated was examined microscopically. Microphotographs
(X 700) of various examples of organisms either observed in the sediment or cultivated therefrom are shown in Figures
325-330, which are reproduced on page 292 from " The Origin of Life : being an Account of Experiments with certain super-
heated saline Solutions in hermetically sealed Vessels " (Watts, 1911, 3s. 6d. net), by kind permission of Professor Bastian.
These figures are as follows : —
Figure 325. Solution (ii). Heated to 130° C. for 10". Mass of Torulae (" Yeasts ").
Figure 326. Solution (ii). Heated to 135° C. for 5". Group of vacuolated Torulae.
Figure 327. Solution (ii). Heated to 135° C. for 5". Bacteria.
Figure 328. Bacteria cultivated from tube shown in Figure 327 as found on ninth day.
Figure 329. Solution (ii). Heated to 130° C. Mass of Torulae with four Bacteria. Cultivated (ninth day).
Figure 330 (from the Second Edition of "The Origin of Life"). Solution (i.). Heated to 100° C. for 20" on
three successive days. Mould of Streptothrix type. (X 300).
In the case of the experiments, the results of which are shown in Figures 327-329, Graham's pure colloidal silica was
used in place of sodium silicate. It was found necessary to use freshly prepared silica or silicate solution.
It is interesting to know that in control experiments, in which the tubes were opened within a day or two of sealing,
no organisms were observed.
289
290
KNOWLEDGE.
August, 1913.
action of radium salts on sterilised bouillon, and his
experiments produced a "nine days' wonder" at
the time. Mr. Soddy, however, showed shortly
afterwards that the phenomenon was of a purely
chemical nature, no living matter being produced.
Quite recently, Professor Leduc has described
certain inorganic preparations (called " osmotic
growths ") which resemble living bodies in some
respects. An " osmotic growth " may be obtained
by dropping a piece of a soluble calcium salt into
a solution of carbonate, phosphate, or silicate. The
dissolving calcium salt is diffused into the solution
and produces an insoluble carbonate, phosphate, or
silicate of calcium, forming a colloidal membrane
around the partly dissolved calcium salt. This
membrane offers far more resistance to the passage
of dissolved salt than it does to that of water.
Hence pressure is set up and water flows into the
membrane, distending it until all the calcium has
been used up and the membrane can no longer bear
the pressure. The phenomena resemble, in a way,
those of growth and assimilation of nutriment as
exhibited by living beings, and the distended mem-
branes assume forms not unlike those of certain
species of marine life. It is only by a stretch of
imagination, however, that we can speak of such
" osmotic growths " as possessing life ; but they do
help to illustrate the difficulty there is of drawing
a hard-and-fast line between living and non-living
matter. (See Figures 322-324.)
Seeing that life as manifested in this world is
always associated with protoplasm, the suggestion
readily arises that protoplasm, so to speak, is
naturally alive ; that the chemist has only to
synthesise this body in order to produce
living from non-living matter. A good deal of
attention has been drawn to this theory by Professor
Schafer's recent presidential address to the British
Association on the origin of life. But the
theory is not a new one. Similar views have
been expressed by Professor Haeckel ; and the
present writer in 1909, as the result of a some-
what different manner of viewing the question,
expressed a conviction that chemists had only to
synthesise protoplasm in order to produce living
matter.* This synthesis has not yet been carried
out, but no doubt it will one day be brought about.
Since the day in 1828 when Wohler first synthesised
urea from ammonium cyanate, and thus broke down
the artificial (though convenient) distinction between
inorganicandorganic bodies, chemists have succeeded
in building up from simpler forms of matter an
enormous number of bodies hitherto only obtainable
from animals and plants ; and everything indicates
that the progress of chemistry will continue until all
organic products will be included in this category.
Does this view of the subject, however, justify us
in holding a purely materialistic view of life, as
some biologists (e.g., Professor Sir E. Ray Lankester)
seem to believe ? The reply to this question
depends largely upon what we mean by life,
Professor Schafer is very careful in his address,
already referred to, to indicate that by " life " he
does not mean " soul " ; and one cannot help
contrasting his cautious and scientific attitude in
the matter with the somewhat unscientific
impetuosity of Professor Sir E. Ray Lankester,
who has informed the readers of the Dally Mail
that for him this distinction does not exist.
Considered purely as a phenomenon occurring in
the physical realm, one is certainly justified in
looking for a scientific, that is, a mechanistic (or
materialistic, if one so pleases to term it) theory of
life. But this is not the last word on the subject.
Metaphysics begin where physics leave off, and the
problem of life still exists for the philosopher when
it has been solved by the man of science.
Looked at genetically, living matter, as we have
indicated, appears to differ but slightly from that
which is called non-living : the one seems to merge
into the other. So must we look at life to under-
stand it scientifically. But to understand life
philosophically we must look at it when most
highly developed or (to speak more accurately)
manifested : not at the moment of its birth. In
other words, we must study man. And here the
distinction between the living and the non-living
becomes manifest. Matter — non-living matter — is
essentially inert. Man is essentially active. So
far as low forms of life are concerned, the
biologist may explain their apparently spontaneous
activity as the result merely of reflex action ; that
is, as the reaction to forces operating from without,
and thus involving nothing opposed to the charac-
teristic inertia of matter. But psychology forbids
us to believe that man, though subject to outside
influence, is moved only from without. In fact,
considered philosophically, the problem of life be-
comes the problem of soul and consciousness ; and
it is then evident that no materialistic explanation is
possible. For, since matter is known to us only in
terms of consciousness, the attempt to explain con-
sciousness in terms of matter at once places us in a
vicious circle from which there is no escape save by
repudiating our materialism.
There seem to be only two alternatives, (i) the
universe is unintelligible, or (ii) all things are the
product of " spirit " (if I may use this term to
designate that reality whose characteristic property
is consciousness) ; and the first of these alternatives,
I think, is put out of court by the fact that as our
experience widens so do we find the universe in-
creasingly intelligible.
Looked at from this standpoint, then, matter is
the first and lowest product or manifestation of
spirit. As such its properties seem to contradict
those of spirit. As such it is inert and lifeless.
But, itself the product of spirit, it forms the vehicle
for increasingly full manifestations of spirit. The
degree of manifestation depends upon the form and
complexity of the matter. At the protoplasmic
stage of evolution the manifestation begins to exhibit
See the present writer's " Matter, Spirit, and the Cosmos" (Rider, 1910), Chapter IX, " On the Origin of Life."
August, 1913.
KNOWLEDGE.
291
Figure 322.
Figure 323.
Figure 324.
Osmotic Growths reproduced from " The Mechanism of Life," by kind permission of Dr. Stephane Leduc.
292
KNOWLEDGE.
August, 1913.
'mm*-
Figure 325.
Torulae (Yeasts).
X/0
^o
X>
Figure 326.
Vacuolated Torulae.
«#!
Figure 327.
Bacteria.
Figure 328.
Bacteria cultivated.
'
Figure 329.
Mass of Torulae.
Figure 330.
Large Mould (Streptothrix).
ORGANISMS OBSERVED IN PROFESSOR BASTIAN'S EXPERIMENTS.
August. 1913.
KNOWLEDGE.
293
the properties of spirit more clearly than heretofore,
and we call the matter "living" because we recognise
the kinship between its spirit and that which we call
" ourselves." The raisoti d'etre and purpose of the
whole process is, I believe, the differentiation of homo-
geneous spirit into individual, self-conscious units
or souls capable of true happiness — the one thing of
absolute value. This is only perfectly achieved in
man. Of course, a theory so wide and comprehen-
sive as this deserves more than the bald statement
here alone possible. I have attempted a fuller state-
ment, though very inadequately, in the essay already
referred to ; and I must also refer the reader to the
remarkable metaphysical treatise of the Swedish
philosopher, Swedenborg, entitled " The Divine Love
and Wisdom," which is the chief source of these
views concerning the ultimate significance and
nature of life. My primary reason for calling
attention to the theory here is to indicate how
entirely it fits in with the doctrine of evolution and
the latest scientific view concerning the possibility
of the spontaneous generation of life.
CORRESPONDENCE.
THE NUMBER OF "DOUBLE" STARS.
To the Editors of " Knowledge."
Sirs, — In your number for June, on page 239, Mr. E. Holmes
criticises a correct statement of the late Mr. F. W. Henkel as
to the number of known double stars. The words he quotes
are : Perhaps as many as twelve thousand such couples are
known." I take exception to his criticism ; the most correct
word of these ten is perhaps. Further, the expression
standard authority " is out of place ; there is no one
standard authority. Let me explain. The branch of
astronomy known as "double stars" (two stars in close
juxtaposition as viewed from the earth) has become very
expansive since I commenced observing double stars in 1881 ;
the great increase in the optical power of recent telescopes
has brought thousands of optical pairs of stars upon record.
The chief merit of these modern observations is that they
are made with the finest instruments and most skilled
observers in this branch ; many of these observations
are duly recorded in Mr. Burnham's " Magnum Opus," in
1170 pages, and the total number of double stars which he
gives therein is thirteen thousand six hundred and sixty-five
(not fifty-five, as given by Mr. Holmes). This work was
published in 1906 by the Carnegie Institution of Washington.
But of what does this consist ? I opened this catalogue at
random and it happened to be page 112 ; this is what is there
(with thirty-three properly observed pairs) : —
Position
No.
Angle.
Distance.
Magnitudes.
Year.
5564
116°-3
15"±
8-9, 11
1830 +
5568
331 -8
7±
11 = 11
1834-3
5575
305 ±
20 ±
6 17-18
1820 +
5577 ]
70 +
2 ±
13 14
1820+
305 ±
25 ±
15
1820 +
5578
53 -8
4±
10-11,11-12
1830 +
5587
69 -4
25 ±
9-10, 10
1830+
5588
9
• . >
5589
35 ±
12±
11 12
1828 +
5593 |
210 +
135 ±
5
1873-29
130 ±
5 ±
9-0 10-0
1873-29
5596
CI. IV
8 11
. ..
5601 |
22 -5
15 +
10-11,14
1830+
208 -0
18 ±.
14
1830 +
5602
CI. IV
8-9 10
...
5607
CI. IV
8 11
, . ,
5609
130 ±
15 +
9 10
1820+
5610
33 -27
1783-09
5611
...
...
9-1 ...
1902-
5612
139 -0
15 ±
9-10,11
1830+
Upon referring to Vol. II (notes) I find there is no further
information given to Nos. 5568, 5577, 5578, 5596, 5602, 5612 ;
to Nos. 5564, 5575, 5587, 5593, 5611 there are recent and
accurate measures given ; therefore the Herschel approxima-
tions might have been abandoned and not again, reprinted.
They are already in Smyth's " Celestial Cycle " and Gledhill's "
Handbook" ; Nos. 5588, 5589, 5601, 5607, 5609, and 5610 have
notes, and there seems no need to have again numbered them,
nor to have included them in a good reference catalogue, except
among the notes or in a table in the Introduction.
The general result is that on page 112 there are fifty pairs
of stars : of these, seventeen are as just quoted in detail, none
of which should have so appeared in an accurate and up-to-
date catalogue, except as mere notes. The whole volume is
similar to this, and the 13,665 pairs or double stars may be
safely reduced by at least twenty-five per centum, and we get
about nine thousand pairs worthy of inclusion in the tabular
catalogue : the R.A.'s and Declinations are given for an old
epoch (1880). Then this only includes stars to minus thirty-
one degrees ; none of Innes's valuable work, or of other
southern observers, is included. So Mr. Henkel's "perhaps
as many as twelve thousand such couples are known " is a
statement not very far from the correct number at present
published, mere estimations omitted. From Mr. Holmes's
reference to other catalogues of double stars one is lead to
believe that he is unacquainted with the contents of that
excellent catalogue by Mr. T. Lewis, published also in 1906.
While the catalogue of Mr. Burnham is collected from all or
many sources since 1780, and is still far from complete or
homogeneous in character — though a work of reference so far
as it goes — that by Mr. Lewis is formed upon a definition
plan, being based upon a systematic series of observations of
about three thousand double stars by W. Struve, with which
have been incorporated in detail all known and good observa-
tions until about 1904. Much valuable information upon the
orbits of the more interesting binary stars is given — as also
in Mr. Burnham's catalogue. So it may be truly called a
standard work of reference for W. Struve's stars, and it will
be used for many a year ; it does not touch those modern
pairs of bright stars with very faint stars within about 1",
observed with instruments of 25-in. to 40-in. object glasses. So
much for the visual pairs, few of which are " binaries."
What of the spectroscopic binaries, which are of the
greatest interest ? Their known number is already consider-
able. None of these are as yet thought to be worthy of
inclusion in a so-called standard catalogue of " double stars."
Mere numbers will not make a standard catalogue ; uniform
quality, completeness, and up-to-date epoch and material is
what we should expect.
Oxford. f. A. BELLAMY.
P.S. — I should like to mention that this letter was written
quite in ignorance of Mr. Henkel's death, and it was in type
before I was informed of it.
THE AGE OF THE EARTH
By E. JOBLING, A.R.C.Sc, B.Sc, F.C.S.
The discovery of the embalmed corpse of one of
Egypt's ancient kings or the unearthing of some
hieroglyphic inscription apparently dating back to
Biblical times, are items of information which, when
they reach the public ear, awaken at least a transient
interest in the probable antiquity of the one or the
bearing of the other upon the history of the peoples of
the world. The call of the past is an appeal to which
few of us are really irresponsive, though in most the
receptive faculty gets dulled by inactivity, due in
large measure to the lack of that divination
which sees interest in objects of almost everyday
acquaintance.
To comparatively few, for instance, has it ever
occurred that in the age and life-history of that
world upon which they " live and move and have
their being " is to be found a problem of keener
and more lasting interest than either of the above.
The indifference of the many to this question cannot
nowadays be attributed to a prevalent unquestioning
belief in the Scriptural computation which ascribed
to the earth a longevity of between six and seven
thousand years; for this form of mental paralysis
is happily now a thing of the past. It can only be
the absence of any acquaintance with the general
trend of scientific thought which debars them from
the very real pleasure to be derived from the story
of man's endeavours to delve into the unknown.
After all, to determine the age of the earth is a
far more difficult undertaking than to assign the
mummified king to his position in the Egyptian
dynasties or to unravel the hieroglyphics of a
Babylonian column. The presence of a coin or
inscription in the one or a scientific deciphering of
the other solves the respective problems ; but in the
case of the earth the difficulties encountered are not
so easily overcome. The shape of the earth has to
be determined, its strata have to be laid bare, its
oceans weighed, and a thousand and one other
investigations satisfactorily completed before even
the data are amassed by means of which we hope
to realise the vast stretches of time that preceded
the very earliest of historians. Stupendous as the
obstacles are, however, sufficient is known already to
fling into the misty past a beam of light powerful
enough to reveal with tolerable certainty the features
of the earth as they presented themselves, say, a
hundred million years ago, and to dispel to some
extent the darkness of an even greater antiquity, if
we call to our aid a little justifiable hypothesis.
Already it has been hinted that only in quite
recent times has the question been approached
scientifically. Time was when " catastrophism "
was the current idea, and men believed that the
earth, and indeed the whole solar system, had
suddenly sprung full-fledged into being at some
ridiculously recent date. When, however, the
foundations of geology came to be laid by Hutton
and Lyell, the immensity of the time required for
an orderly deposition of the sedimentary rocks or
the elaboration of the organic world laid such hold
upon their imagination that " catastrophism " was
abandoned for the other extreme, " utilitarianism,"
which relegated the birth of the earth to the very
beginning of time and refused to adopt any smaller
chronological standard than an " eternity."
These somewhat ludicrous extremes are now, of
course, replaced by more reasonable views, which
owe their conception to the application of the
modern scientific spirit and the ever - growing
accumulation of experimental data. The iconoclast
who assailed and overturned the above extravagant
hypothesis was Lord Kelvin, then Sir W. Thomson,
who, in the few years following 1862, published
papers in which he proceeded by several physical
lines of reasoning to an estimate of the earth's age
so small comparatively as to make the then-ortho-
dox geologists gasp with surprise and indignation.
These estimates of his — historically interesting, if
now perhaps obsolete — will be briefly dealt with
first before attention is turned to other more reliable
evidences advanced in recent years.
It would be as well, however, before discussing the
theories if we first obtain a clear idea of the various
phases of life-history through which the earth has
passed in order that no confusion may subsequently
arise as to the relative significance of the numerical
values obtained.
Imagine, then, a vast molten globe — the product,
we may take it, of the condensation of a nebular haze
— rapidly rotating round the sun. The influence of
the latter would be such as to develop vast tides in
the liquid magma of the rotating body, one of w hich
tidal waves, the late Sir G. Darwin suggested, might
conceivably have assumed sufficiently large propor-
tions as to disturb the stability of the whole, and to
be itself trundled off into space, where it would con-
tinue to revolve around the remainder as the infant
moon. Sir G. Darwin, by-the-by, has calculated the
time which has elapsed since this separation to be
fifty-six million years. Its birth-pangs over, what
we now know as the " earth " starts upon its career
as a separate member of the solar system. Prob-
ably soon after the moon's departure the earth had
cooled enough to permit of the formation on the
sea of magma of floating islands of scoria, which
would assume larger and larger dimensions until the
outer crust of the earth was entirely solid and what
is called in the earth's history its cousistentior status
was inaugurated. Further cooling resulted in the
condensation of some of the constituents of the
atmosphere, which products would collect in
294
August, 1913.
KNOWLEDGE.
295
pockets on the surface, and thus the configuration
of continents and oceans arose. Sooner or later,
yet another era would be ushered in by the
commencement of those processes of denudation and
deposition which, throughout the long ages following,
have reared new continents upon the ruins of the
old, and which still manifest their slow-moving but
irresistible activities before our eyes. At what period
signs of life appeared and the earth first became
inhabited we cannot stay to discuss, but must revert
to our original theme.
I. — Kelvin's Theories.
During mine-sinking operations it is noticeable
that as the shaft penetrates deeper and deeper the
temperature slowly and regularly increases. In
different places the temperature-gradient is not the
same ; for external conditions necessarily disturb it
in the topmost strata, and we have not yet delved
deep enough to reach the lower regions where
uniformity prevails. But from observations made
an average can be taken, and from this it is possible
to deduce mathematically an estimate of the earth's
age. The problem resolves itself into the following.
Knowing the conductivity of the earth's crust, and
assuming a certain uniform initial temperature, what
time must elapse before it cools to such an extent
that the temperature-gradient over a certain thick-
ness is that which we find to obtain now ? The
mathematical expression of this has been solved by
Kelvin, who arrives at the result that the whole
period since the earth was molten amounts to about
twenty million years, and certainly could not exceed
four hundred million years.
Another method of his depends upon the braking
action which the tides exert upon the rotation of the
earth. Since the earth rotates more quickly than
the tidal bulge, it follows that the frictional effect
thus brought into play must have slowly diminished
the period of the earth's revolution. As a time-
keeper, in fact, the earth loses some twenty-two
seconds in each century, and though this appears
a negligible quantity it nevertheless mounts to
appreciable proportions when extended over millions
of years. Consider, then, for a moment, what this
retardation implies. We all know that the earth is
not a perfect sphere, but oblately spheroidal, having,
in fact, almost exactly the shape it would assume if
it were all molten and revolving at its present rate.
If the earth, however, had been rotating very much
faster when in the liquid condition, and solidi-
fication had then taken place, the shape would
differ considerably from what we find it to be now.
Even if it had been rotating three per cent, faster,
the difference would be quite noticeable ; for a greater
polar flattening would result and the disposition of
the oceans could not be as at present ; and since
mathematical reasoning demonstrates that one
hundred million years ago a three per cent, increase
in the rotation would obtain, the deduction is drawn
that any greater antiquity than one hundred million
years can only be regarded as improbable.
The remaining argument is drawn from a con-
sideration of the origin of solar heat and its
dissipation by radiation, and led to the conclusion
that the sun has illuminated the earth only during a
period which is probably less than even one hundred
million years and certainly not much more.
This computation, however, and to some extent
the second, are based upon data which are neces-
sarily vague and indeterminate, and in consequence
much reliance cannot be placed upon the results.
As will be shown presently, even the first of the
Kelvin estimates has to be rejected on the score of
recent discovery ; so now there is not one of his
methods of estimation to which exception cannot be
taken.
In their day, nevertheless, they served a useful
purpose ; for by awakening geologists from their
dream of an unlimited credit on the bank of eternity,
and compelling their reluctant limitation to a less
exorbitant draft, the above intrusion on the part of
physics at least prepared the way for fresh lines of
argument of less doubtful validity. Naturally,
Kelvin's estimates were at first indignantly dis-
credited, though without any apparent effect upon
the firmness of Kelvin's attitude. In vain his
opponents appealed to their ancient traditions —
geologists to their succession of strata, and palaeonto-
logists to their evolution of types, both of which
were believed to require an aeon of time— he simply
ignored all with disarming unconcern.
But though the most eminent of the physicists
thus arbitrarily defined his isolated position, there
were others in his own sphere of activity who
refused to recognise the finality of his results, and
were disposed rather to compromise with geologists
on the question. Thus, Sir G. Darwin, in a review
of the three theories, pointed out some of the
uncertainties which surrounded them ; whilst
Professor Perry, in his inimitable style, advanced
cogent reasons for believing that the Kelvin com-
putation erred considerably on the side of under-
estimation. Indeed, Perry was quite willing to
concede an estimate four times greater than the
greatest of Kelvin's.
These more reasonable views now stand fully
justified in the light of more recent knowledge.
The first and, as we have mentioned, the most
trustworthy of Kelvin's arguments was vitiated
during the last few years of the nineteenth century
by the discovery of radioactivity and its allied
phenomena. This is a point, however, which has to
be deferred to a later stage. It is evident that some
other methods of attacking the problem were urgent,
and as such have happily been forthcoming we shall
proceed to discuss them.
II. — Solvent Denudation.
FYom a consideration of the weathering forces
which on every hand mould the features of con-
tinents, Professor Joly derives a method for
determining the age of the earth since the time
when the latter attained its consistentior status.
296
KNOWLEDGE.
August, 1913.
Looking for a ready means of computing the
total effect produced by the multifarious denudation
agencies, he naturally turned to rivers, as being the
vehicles for the removal of detritus, and exercised
himself to find some constituent which, while
capable of sufficiently accurate measurement, should
be non-cyclic in character, that is to say, should
accumulate in the sea without possibility of return.
The well-known fact that the sea, and inland lakes
in particular, are slowly growing salter and Salter
led Joly to select sodium — in the combined state, of
course — as the element best satisfying the necessary
conditions. The broad outline of the method is
now easy to understand. The volume of the ocean
has first to be estimated and then, from a knowledge
of its average chemical composition, the total
quantity of sodium at present in it can be obtained.
This sodium must have accumulated there ever
since denudation began, and if, therefore, we divide
its total by the calculated amount of it which enters
the ocean annually from the rivers, an uncorrected
estimate of the earth's age will result.
The amount of sodium in the sea at present is
known to within a few per cent., but the quantity
discharged per annum by all the rivers in the world
is not so well authenticated, being much more
difficult to determine. The sodium content of rivers
is so variable a quantity that the water of a large
number must be analysed before any reliable data be-
come available ; a difficulty, of course, which time will
entirely remove. The magnitude of the quantities
in question will be realised from the statement that
if all the salt at present in the ocean were con-
solidated into a uniform layer of rock salt upon
the land area of the globe the earth would be
covered to a depth of about four hundred feet.
Without going into numerical details the fact
may be stated that the estimate of the earth's age
derived from the above-mentioned data amounts to
practically one hundred million years.
To this number several corrections must be
applied. The most important of these refers to
what is known as " wind-borne sodium," i.e., to
those impalpable particles of salt which are carried
inland by air currents. This factor slightly disturbs
the non-cyclical character of the process, but only
requires a small correction (six to ten per cent.).
Relatively insignificant, too, is a correction which
takes into account the land deposits of sea-salts.
The only other conceivable corrections are inherent
in the method itself, or, more precisely, in the
assumptions which lie at the basis of the method.
There is, for instance, the possibility that in the
remote past the conditions which determined the
rate of denudation were far different from those
which prevail to-day. The sun may have been much
less powerful, or, on the other hand, the elements
may have been more active, and therefore more
destructive. Again, there is every reason to believe
that the ratio of land to sea has been far from
constant during the long ages of the past. But if
uniformity of the past and present conditions be
assumed, as indeed seems most likely, and the other
uncertainties be duly allowed for, the time which
has elapsed since the "waters under the heavens were
gathered together in one place, and the dry land
appeared," runs to between eighty and ninety
million years.
A couple of years ago the fundamental assump-
tion underlying Joly's method was challenged by
Dr. Becker, who put forward some very interesting
views. He pointed out that the sodium of the
ocean is derived mainly from igneous rocks, and
that when denudation began these rocks were the
sole constituents of the earth's crust. A very
different state of affairs obtains nowadays. Sedi-
mentary rocks are the obvious features of surface
strata, and the igneous rock lies buried far beneath
them. Does not this imply that the rate of decom-
position has changed considerably since the early
days of the earth's youth ? For, whereas the neces-
sary rocks were then freely exposed to denudation
influences, the upper layer of decomposition pro-
ducts now arrests decay. In other words, the rate
of decomposition, being dependent upon the area of
exposure, has diminished throughout the ages in the
same way as a sum of money would diminish if sub-
jected to a certain percentage deduction annually,
each deduction being calculated on the sum still
remaining at the beginning of the year. That is to
say, it has varied according to an exponential law.
The estimate of the earth's age, worked out on this
formula, gives a somewhat smaller value than by
Joly's method, viz., from fifty to seventy million
years.
However, the two results are of the same order of
magnitude, preference perhaps being given at present
to Joly's value. Let us see if this is borne out by
the next computation.
III. — Stratigraphy.
The reverse of the preceding method would
obviously consist in determining the rate at which
the strata are being deposited ; and then, from a
knowledge of the maximum depth of the stratified
rocks, an estimate of the earth's age readily follows.
Sir A. Geikie, even before Lord Kelvin had assaulted
the geological stronghold, held that one hundred
million years would suffice for the history of the
sedimentary rocks. More recently Professor Sollas,
Professor Joly and others have discussed the
question.
The uncertainties attached to the method, how-
ever, render it practically impossible to obtain any
reliable result. From the observations of geologists
in different parts the maximum thickness of the
deposits laid down during the various geological
epochs has been estimated, but the accuracy of the
measurements decreases with the increasing
antiquity of the formation concerned, until, when
pre-Cambrian times are reached, anything but the
merest guesswork becomes impossible. Even were
this difficulty removed, the intermediate lapses of
time which are represented by unconformities and
August, 1913.
KNOWLEDGE.
297
other appearances must, of necessity, be disregarded.
When it comes to measurements of the rate of
accumulation of the various strata, still greater
difficulties are encountered. Theoretically, it is
only necessary to measure the annual silt-loads of
various rivers, as well as the catchment area, and
the rate of deposition ensues. But, in practice, the
rates are found to be so divergent and variable that
the average counts for little. As Joly points out,
we are at liberty to assume anything from a foot to
a few inches deposition per century. Taking the
rate of accumulation to be four inches in the
century, the age of the sedimentary column, which
is between sixty and seventy miles thick by the best
estimate, then works out to be about one hundred
million years. Sollas gets thirty millions ; Joly gets
eighty million years. The latter is probably the
more likely of the two, so we shall not be far wrong
if we consider our one hundred-million year com-
putation as fairly near the mark.
IV. — Radioactivity.
Among the many wonderful possibilities which
radioactivity has to offer, the determination by its
aid of the age of the earth may be the least
important ; but it is undoubtedly one of the most
interesting, opening up as it does such a splendid
field for discussion and speculation.
In the first place, it deals the death-blow to
Kelvin's thermodynamic method. The disintegra-
tion of a radioactive body is known to be accom-
panied by a spontaneous evolution of heat energy,
and, considering the widespread character of these
bodies throughout the earth's crust, the total heat
developed in this way can be no negligible quantity.
Indeed, so far as present estimates go, it more than
accounts for the earth's annual loss by radiation —
truly an embarrassing position for the earth, as will
be shown in a moment. The supposition, then,
that the earth is merely a cooling body, whose
primitive stock of heat is being slowly depleted, must
be modified in order to take account of the new
factor. Let us examine afresh our conception of
the life-history of the earth.
The fact that the molten earth contains a con-
siderable store of long-lived radioactive elements
would not appreciably retard its cooling until the
consistentior status was reached. Then, on the
formation of the surface crust, the rate of cooling
would be reduced to a very small fraction of its
former value ; comparable, in fact, with the heat
liberated during elemental disintegration. Near the
surface of the earth this heat is sufficient, we have
seen, to make good the radiation loss ; whereas in
the interior, where escape is impossible, the heat
generated cannot but have accumulated during the
long geological epochs. The final result is evident.
Not from without, by collision with some wandering
star, but from within, by her own irrepressible
vulcanicity, is the destruction to come which is to
return the earth to her pristine state, to begin again
her life-history, perhaps for the nth time, where n
represents an unknown quantity. In a similar way
the long duration of the sun's heat is accounted for,
and another theory of Kelvin's exploded.
But let us get back to age determination. The
basis of the radioactivity method will be clearly
understood if it be remembered that radium is an
element whose parentage is known and whose
descendants to many generations have been fairly
definitely established. In other words, this singular
element has been proved to be one of a series which
begins with uranium and proceeds down a scale of
radio-elements of diminishing atomic weight until
the final stable substance, now thought to be lead, is
reached. The disintegrating process is accompanied
at almost every stage by a loss of what are called
a particles, which themselves have recently been
shown to be identical with helium atoms.
Of course, the process of degradation is incon-
ceivably slow, though the time-rate for each stage
has actually been calculated from laboratory observa-
tions. The number of helium atoms discarded
during each of the transformations is likewise
known. Assuming, then, that all these discharged
atoms have accumulated in situ in any geological
formation, it is only necessary to determine in a
specimen mineral the ratio of the occluded helium to
the still-remaining radioactive element in order to
arrive at an estimate of the age of the strata from
which the mineral was taken.
The Hon. R. J. Strutt, in particular, has examined
from this point of view many minerals taken from
strata of the different geological epochs. His results
are too numerous to quote, but so far they have not
been particularly satisfactory. Even in material
obviously contemporaneous, for instance, the varia-
tions in the geological ages turn out to be very
considerable. The weak point of the whole method
seems to lie, not in the theoretical assumptions
involved, but rather in the improbability of a
complete helium accumulation. It appears likely
that the varying experiences to which the helium-
bearing formations have been subjected throughout
their existence — such as changes of temperature and
pressure or the solvent action of percolating waters —
have all contributed to an appreciable alteration in
the amount of helium accumulated. The advantage
that the method otherwise possesses, in that each
determination is an independent estimate of the
geological age, is thus swamped by the disability just
referred to, and any results which are the outcome
of such a method must consequently be received
with caution.
The problem has recently been approached from
another standpoint, and, at first sight, one more
reliable. If lead is really the ultimate product of
the disintegration of uranium — and much evidence
has been adduced in support of this view — then from
the uranium-lead ratio supplementary estimates are
possible. Professor Boltwood has attacked the
problem of the age of the earth from this assumption,
and is led thereby to attribute to a number of
uranium-bearing minerals an age which ranges from
298
KNOWLEDGE.
August, 1913.
two hundred to one thousand three hundred million
years ; though since the geological positions of the
rocks examined are not available the figures do not
convey much.
Considered broadly, the evidence of radioactivity
is to assign to the earth an age considerably greater
than results from any other method. This either
means that the accuracy and, perhaps, the funda-
mental assumptions, of the other methods are
impugned, or that the radioactivity method itself
is founded upon hyphotheses which are not justifi-
able. There is even some reason for believing that
the latter is not altogether out of question. Thus,
though no acceleration in the rate of disintegration
of uranium has yet been observed in the laboratory,
it is not beyond the pale of possibility that some
conditions did prevail in the earlier stages of the
earth's history which are not experimentally realis-
able to-day, but which then determined an increase
in the rate of decay. It would be unwise, however,
to pursue speculation further, notwithstanding an
innate desire to cast doubt upon a method which, by
disturbing the gradual maturing and stabilisation of
our views before its appearance, has thrown us back
into what Professor Schuster describes as " the
primitive state where no opinion is absurd and every
hypothesis justifiable." Until further evidence of a
more convincing nature is forthcoming, we may
provisionally assign an age of not less than one
hundred million years to this earth of ours.
Of course, this estimate takes us back only to the
consistentior status. Whether, before that, the sun
was still pouring his beneficent rays upon the earth,
so that the present estimate of the earth's age is not
merely an estimate of the sun's activity, or whether,
instead, after solidification of the outer crust, the
earth rolled through space as a dead world shrouded
in darkness save " where her volcanoes glowed red in
the eternal night," cannot be answered decisively.
From present evidence it appears very likely that
the sun shone brightly long before the earth came
into existence, and the one hundred million years
would not then have to be very materially increased
in order to take us back to the very birth of the
earth. On the other hand, it may be that the
discrepancies between the results derived from a
consideration of denudation and of radioactivity
are to be interpreted as pointing to long aeons of
time during which the earth slept as she rolled
through space.
It would be an interesting diversion to consider
whether the whole scheme of evolution outlined by
Darwin and others could possibly be worked out
within such a comparatively short period as we have
accepted. Are one hundred million years time
enough for that evolution of the organisms which,
starting with a shapeless mass of protoplasm, deter-
mined its development through countless structures
of increasing complexity, until finally man himself
was reached ? At this stage only the briefest of
answers can be given. Eminent biologists declare
that the period is ample and the ordinary doubts
of the layman may therefore be laid aside.
The period of one hundred million years, then,
which have been conceded to the earth, is from most
points of view a reasonable estimate. It cannot be
expected, however, that finality is attained. This
estimate, like its predecessors, may have to be dis-
carded if further investigation requires it, though
as yet there seems no valid reason for abandoning it.
Nevertheless, our ideas on the subject must be
pliant and versatile, our minds ready to recognise the
meaning of revolutionarydiscovery. The best attitude,
perhaps, is that which regards the one hundred
million years as the earth's minimum age, and is
prepared, if occasion demands, to consider im-
partially an estimate of greater — it may be much
greater — magnitude.
CORRESPONDENCE.
SPURIOUS DIAMETERS OF STARS.
To the Editors of " Knowledge."
Sirs, — Reading recently the papers of Sir W. Herschel,
published last year by the Royal and Royal Astronomical
Societies, 1 was surprised to see his statement that increase
of magnifying power with the same aperture of object glass or
mirror causes a decrease in the size of the spurious discs of
stars. I was fully under the impression from reading modern
works that the reverse was the case. I know that increase of
aperture means decrease of diameter of spurious discs, but
the other was news to me. Herschel's words are : " By many
observations their spurious diameters are lessened by increasing
the power, and increase when the power is lowered." In
Vol. II., page 303, again he says that the diameter of spurious
disc of <t Aurigaewith power 227 was 2"- 5, and that of a Tauri
with power 460 was 1" 46'", and with 932 it was 1" 12'", while
that of o. Lyrae with power 6450 was 0"-3553. I should be
glad if some of your astronomical readers would reconcile
these extracts with present-day ideas.
THEODORE B. BLATHWAYT.
Cape Town.
STELLAR DISTANCE UNITS.
To the Editors of " Knowledge."
Sirs, — I notice some comments in your July issue regarding
names for the planetary and stellar distance units. In my
opinion the names suggested are quite impossible — ugly of
look and ugly of speech. The names for any unit of measure
should assuredly be short and easy to pronounce. Dr.
Crommelin's suggestion of " astron " for one is quite
acceptable. But why bother about the inner significance of
the words at all ? An arbitrary adoption would do quite as
well. Why not follow the course adopted in electrical measure-
ments ? Here we have " Watts " and " Amperes " ; in
Astronomy we might well have " Keplers " and " Newtons."
Let the former stand for the shorter or earth-sun unit, and
the latter for the longer " light-year." In order to destroy the
personal look about the terms they might well be abbreviated
to " keps " and " newts." As alternatives the names of the
men who (a) first determined the earth-sun distance and
(6) who first used the " light-year " of a unit of measure might
be used.
A. J. H.
Aberystwyth.
A PLEA FOR A BRITISH FOLK-MUSEUM.
By W. RUSKIN BUTTERFIELD.
A proposal has recently been made to utilise the
Crystal Palace and grounds for a National Folk-
Museum on the lines of the famous Nordiska
Museet at Stockholm, with its open-air department
of Skansen.
The last two decades have witnessed the forma-
tion of folk-museums in various parts of Europe,
and especially in the Scandinavian countries. In
addition to the one mentioned at Stockholm, Sweden
possesses others at Lund, and at Bunge in the island
of Gotland ; in Norway similar institutions have
been established at Christiania, Lillehammer,
Elverum, and Hamar ; and in Denmark at Copen-
hagen. Their raison d'etre is to illustrate in a
concrete manner the evolution of national culture
and characteristics ; to trace the modes of life of the
people in times past and to preserve represen-
tative examples of national buildings, domestic and
other appliances, costumes, personal ornaments —
in short, to bring together in one locality all such
objects as best serve to reconstruct the conditions
of life in their respective countries from remotest
times.
In no country is a national folk-museum so neces-
sary as in England, because in no other country is
there such a dearth of distinctively national objects,
and also because no other country has outgrown its
past so rapidly and so completely in regard to in-
digenous customs, amusements, and modes of life
generally. What an unalluring sight is presented,
for instance, by the interiors of the smaller homes of
the land at the present time. The furniture, pottery,
and other objects are almost all of the factory type.
Here and there, it is true, one does find an old
corner cupboard, a lace christening cap, or a piece of
slip-ware made at some forgotten local pottery and
containing perhaps a presentation inscription com-
memorating a wedding or a betrothal ; but these old
folk-objects are few and far between. During the
Victorian period especially there existed a profound
apathy, if not antipathy, for what was deemed old-
fashioned. Mural paintings were hidden behind
coats of lime-wash, oak-panelling was torn from
the walls, and immemorial seasonal customs in town
and village alike dwindled to their final abandon-
ment. No less striking were the changes wrought
by the concentration of industries and by increased
facilities for transport. Home industries, such as
weaving and lace-making, and local crafts, like those
of the potter and the basket-maker, were diverted
from the villages to factories in the larger centres
of population. A national folk-museum would
take account of these several changes and preserve
the links between the past and the present.
The British Museum at Bloomsbury and the
Victoria and Albert Museum at South Kensington
are national in scarcely any other sense than that
they are State institutions. The splendid collections
in the former tell us as much, if not indeed more,
about the ancient Egyptians and Greeks than about
our own peoples and our own land. The equally
fine collections at South Kensington have been
accumulated mainly for the special purpose of
providing objects, irrespective of their place of
origin, to serve as standards in the industrial and
fine arts. Moreover, the methods of exhibition in
these great museums are only partly in keeping with
the spirit of folk-museums. Instead of displaying
collections in formal series in standardised glass
cases, the folk-museums assemble their objects so far
as possible in related groups. But the great failing
of the museums in question lies in their remoteness
from the realities of every-day life. They restrict
themselves too rigidly to things which are merely
rare or precious, or which attain a certain artistic
merit. They pay little or no concern to the ordinary
man and woman. In other words, they touch the
circle of national life only at the glowing centre
instead of reaching to the wide periphery.
Now let us turn to the proposed scheme and see,
so far as is possible in a bare outline, what it is
intended to accomplish. Taking the Crystal Palace
grounds first, it is proposed to establish therein an
open-air museum. Of all the survivals from former
times, none surpass in interest the people's homes.
The first duty, therefore, of the open-air museum
would be to secure ancient houses bearing in a
sufficiently well-marked manner features distinctive
of some period or locality. The buildings would be
taken down and re-erected in the grounds with
scrupulous regard to their original form. It is not
contemplated, it need hardly be said, to ransack the
English countryside and tear buildings from their
time-honoured sites, where there is no danger of
their demolition or serious mutilation, but to rescue
here and there worthy and typical buildings in
imminent danger of destruction. After their
re-erection the houses will be provided with con-
temporary furniture and all appropriate appliances,
the idea being to show them exactly as they
appeared to the people of the time. Some of the
houses might have associated with them old English
gardens, with a columbarium, a well-house, a sun-
dial, and clipped yews. Consider how fascinating
such sights would be, not only to ourselves, but
also to visitors from amongst our kinsmen in the
dominions beyond the seas.
In some cases, instead of removing whole houses,
299
300
KNOWLEDGE.
August, 1913.
it would be sufficient to secure the ceiling, a fireplace,
a panelled room, or the main staircase, and to instal
these in rooms in the Crystal Palace.
Besides domestic buildings, other structures would
be treated in the same way, such as ancient barns
and water-mills. It might even be possible to save
some abandoned and decaying English church
whose preservation is demanded by its age or
importance. Such a church would form the most
appropriate home for the display of ecclesiastical
art. No doubt many people would find it hard to
assent to the removal of a church from its parish,
but such removal and preservation are better than
decay and final ruin.
The scheme provides for the assignment of a
portion of the grounds for our great national games
and pastimes ; here would be a maypole for the
children and a bowling green for their elders. A
dancing floor would be laid out for national dances,
and an open-air theatre prepared for the performance
of historical pageants and stage plays. At Skansen,
spacious enclosures are reserved for living examples
of Swedish mammals and birds. This might be
imitated by a miniature British " Zoo."
As to the Crystal Palace itself, it would serve for
the exhibition of objects of all sorts illustrating the
daily life, occupations, and amusements of the
peoples of these islands. One room could be
devoted to children's toys, another to objects used
by women in indoor amusements, another to the
apparatus and methods of producing fire in past
times (a most seductive subject), another to inven-
tions, another to models to enable the blind to
gain, by tactual means, a knowledge of some of
the more interesting objects in the various depart-
ments. Space would further be required for
developmental series of English metal-work, wood-
carving, pottery, glass, furniture, and textiles ; also
for such things as hand-looms, vehicles, old surgical
instruments, inn-signs, the regalia of guilds and
other societies, stocks, gibbets, clocks, tallies,
charms, cheese-presses, and a multitude of others.
Special stress would be laid upon objects typified
by ornamental lace-bobbins, carved bone apple-
scoops, and costumes, as it is just such things as
these that best illustrate the trend of native culture.
The framers of the scheme point out that it would
be particularly appropriate if a number of rooms in
the Crystal Palace could be devoted to collections
relating to past and present members of our Royal
house, such as portraits, ceremonial robes, and
personal relics. The present writer had hopes at
one time that Stafford House might be converted
into a royal museum after the fashion of Rosenborg
Castle at Copenhagen, but the future of that building
has been settled otherwise.
A national folk-museum like this would illustrate,
by means of actual objects, historical continuity.
After all, the present can only be measured in terms
of the past, and, unhappily, in England our past is
rapidly disappearing beyond recall. If the project
is delayed much longer its effectual accomplishment
will become impossible. Other European countries
are fully alive to the importance of preserving
unbroken the records of national life. There is
little in our past to be ashamed of ; there is much
of which we may justly be proud.
Through the patriotic action of Lord Plymouth,
Sir David Burnett, and of The Times, the Crystal
Palace grounds are now available for some public
purpose. It is desirable, from every point of view,
to take advantage of so unique an opportunity for
promoting the establishment of a permanent and
comprehensive national folk-museum. The central
feature of the situation lies in the fact that, if these
grounds are assigned to some other use, no other
open stretch of land so near London of such
magnitude can ever again be forthcoming. It is a
duty we owe to posterity no less than to our for-
bears, to preserve, while it is still possible, the fast
dissolving links that bind us with the past.
I wish to express my indebtedness to Mr.
Bernhard Olsen, of the Dansk Folkemuseum, Mr.
Hans Aall, of the Norsk Folkemuseum, Mr.
Bernhard Solen, of the Nordiska Museet, and Dr.
Anders Sandvig, founder of Maihaugen Open-air
Museum, for kind permission to reproduce the
accompanying illustrations ; also to Dr. F. A.
Bather and Professor Henri Logeman for valued
assistance.
THE ARTIFICIAL RIPENING OF FRUITS.
The Gardeners' Chronicle for July 19th points out that
the Arabs have for centuries ripened dates artificially by
exposing them to the fumes of vinegar ; and refers to the
ripening of persimmons by the Japanese, who store them in a
closed cask in which the national alcoholic beverage known as
sak6 has been kept. Professor Francis Lloyd's method of
exposing unripe fruits under a pressure (of from fifteen to
forty-five pounds to the square inch) to the action of carbon
dioxide for fifteen to thirty-six hours is also discussed.
What happens in the process is not altogether clear, but
we quote the following remarks : —
" Astringency is due to the action on the tongue of the
tannins contained in the unripe fruit. It disappears if the
tannins are destroyed, or if these bitter substances are
prevented from acting on the tongue. Carbon dioxide seems
to produce the latter effect, and in the following way:
Associated with the tannins in plant tissues are coagulable
substances. Such substances when caused to coagulate
hold the tannins very strongly, so strongly, indeed, that the
latter substances are prevented from giving rise to an
astringent taste when the fruit containing them is eaten. In
short, the coagulated substance plays the part of the coat of a
bitter pill, enabling the latter to be taken untasted. The
explanation may be that which has been given ; but we are
inclined to think that other changes are induced by carbon
dioxide. For example, it is possible that the effect of carbon
dioxide is to hasten the oxidation processes of the tissues, and
hence to cause a partial or complete destruction of the
astringent substances. Whatever be the precise interpretation
of the process the important thing is to ascertain whether a
similar process may be induced in our common large fruits ;
for although artificial ripening is primarily of importance to
the grower of tropical fruits — dates, bananas, persimmons,
and the like — it may prove also of service to the home grower."
August, 1913.
KNOWLEDGE.
30i
Figure 331. Assemblage of buildings within enclosures forming a "summerset," or temporary quarters occupied during
cattle grazing, from Jamtland. Skansen.
Figure 332. Timber-houses from Telemarken. Norsk Folkemuseum.
302
KNOWLEDGE.
August, 1913.
Figure 335. Interior of room from a farmhouse, from
Amager, near Copenhagen. Dansk Folkemuseum.
Figure 334. Farmhouse interior from Urendorf, Halsatia.
Dansk Folkemuseum.
Figure 335. Interior from Telemarken. Norsk Folke-
museum.
Figure 33fi. Timber-house (" Rolstadloftet ") from Gud-
brandsdale. Norsk Folkemuseum.
Figure 337. House in the Maihaugen Open-Air Folk-
Museum. Lillehammer.
Figure 338. Interior of a dwelling at Lillehammer.
THE FACE OF THE SKY FOR SEPTEMBER.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 52.
Date.
Greenwich
Sept.
Sun.
R.A. Dec.
h. m.
1043-9
11 1*9
11 199
11 37-9
11 55-8
12 13-8
N.8'1
6-2
4'3
2 '4
N.o-s
S.,-5
Moon.
R.A. Dec.
h. m. 0
12 8-5 S. i-8
16 46-4 S. 27*6
21 18*5 S. 19*1
° 53'4 N- 7'3
4 59*2 N.28'0
9 55'2 N.i5-4
Mercury.
R.A. Dec.
9 56*5 N.i4"i
10 33 'o u*o
11 8-8 7-4
[i 43-0 N.3's
12 15-3 S.o-5
12 45*0 S.4'3
Venus.
R.A. Dec.
h. m. <,
S 13*6 N. 19*4
8 38-0 18-3
9 2'2 17*0
9 26*1 15-5
9 49-9 13-8
10 13*4 N.i 1 '9
Mars.
R.A. Dec.
5 26'9 N.22"9
5 39-7 23-1
5 5">*i 23-3
6 4'3 23'4
6 i6'o 23*5
6 27-3 23-5
Jupiter.
R.A. Dec.
h. m. 0
8 34-9 S.23'4
8 35-0 23-4
8 35'4 23"4
8 3°'i 23'4
8 37'i 23"4
8 38-5 S-23-4
Saturn.
R.A. Dec.
6"! N.21'2
7't 2I'2
7'9 2I"2
8'5 21-2
8'9 21*2
9*2 N.2I*2
Uranus.
R.A. Dec.
h. m.
20 27 '1
20 26'5
20 26 'o
20 25*5
20 25'
S.19'8
19-9
I9'9
19-9
19-9
20 24*8 S.19'9
Table 53.
Date.
Sun.
P P. I.
Moon.
P
Mars.
P B L T
Jupiter.
P B L I, T T
121 2
Greenwich
Noon.
00 0
+ 21*4 +7*2 24*2
22*6 7*2 318 1*2
23*7 7*2 252*2
24'5 7'i i86'2
25*2 7*0 120*2
+25*8 +6*8 54*2
0
+2i-8
+ 6-9
-16*5
-21-4
- 5-8
+ iS*6
o a 0 h. m.
— 28'7 — i'o 227*1 9 6e
27*5 +0*2 178*9 O 24*W
26*2 1*4 130*8 3 2 m
24*9 2*5 82*8 6 20 m
23*6 3'5 34'8 9 37 »•
-22*3 +4*s 346*9 o 54 c
0 » • ° h. m. h. ra.
-4*6 —1*6 199*9 285*5 423' 2 4'
4*6 i*6 269*0 316*5 2 30 e 1 13 e
4*6 1*6 338*1 347*4 10 27 e 0 22 *
4*7 i'6 47*1 18*2 8 34 r 9 26 e
4*8 i*6 n6'o 49*0 6 41 e 8 36 e
— 5*0 —i*6 184*8 79*6 4 48 e 7 45 e
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Mars, T is the time of
passage of Fastigium Aryn across the centre of the disc. In the case of Jupiter, Lt refers to the equatorial zone; La to
the temperate zone; Tlf T2 are the times of passage of the two zero meridians across the centre of the disc ; to find inter
mediate passages apply multiples of 9h 50£m, 9h 55lm respectively.
The letters to, e, stand for morning, evening. The day is taken as beginning at midnight.
The asterisk indicates the day following that given in the date column.
The Sun continues his Southward march with accelerated
speed. The equinox is passed 23d 3h 53me. Sunrise during
August changes from 5.13 to 5.59, sunset from 6.48 to 5.41.
Its semi-diameter increases from 15' 53" to 16' 0". Outbreaks
of spots in high latitudes should be watched for.
Mercury is in Superior Conjunction 16d 3he ; before that
it is a morning star. Illumination increases from A to Full.
Semi-diameter diminishes from 3" to 2i".
Venus is a morning star, rising 3 hours before the Sun.
Semi-diameter diminishes from 7" to 6". At beginning of
month J of disc is illuminated; at end of month §. Being
North of Sun it is favourably placed for Northern observers.
The Moon.— First Quarter 7d lh 6m e ; Full 15d 0h 46me ;
Last Quarter 23d 0h 30m e. New 30d 4h 57m m. Perigee
ld 7h in, semi-diameter 16' 44". Apogee 15d Noon, semi-
diameter 14' 44". Perigee 29d 6h e, semi-diameter 16' 44".
Maximum Librations, 7d 8° W, 8d 7° N., 23d 7° E.,
23d 7° S. The letters indicate the region of the Moon's
limb brought into view by libration. E. VV. are with
reference to our sky, not as they would appear to an
observer on the Moon.
Eclipses. — A small partial eclipse of the Sun, invisible in
Europe, occurs on August 31st, lasting from 8h 2m e to
9h 42m e ; greatest magnitude 0*15. Visible in Newfoundland,
Labrador, Greenland.
A total eclipse of the Moon, invisible in Europe, occurs on
September 15th, lasting from 10" 53m w to 2h 44m e. Visible
over Pacific Ocean, Australia, New Zealand, and so on.
A partial eclipse of the Sun, invisible in Europe, occurs on
September 30th, lasting from 2h 56m m to 6h 36m m ; greatest
h m
O
12...
23 24-5
3-6
18...
23 20-2
4-9
24...
23 16*1
6-1
30...
23 12-3
7-3
magnitude 0*83. Visible in South Africa, Madagascar,
Mauritius, and South Indian Ocean.
Mars is a morning Star, semi-diameter 4", defect of
illumination nearly a second. It will reach Opposition
early in January, so the season of observation is
commencing. The Earth is in the plane of Mars' Equator
on September 6th ; both poles are then on the edge of the
disc.
Juno is in opposition September 14th, magnitude 7*6.
Ephemeris for midnight : —
R.A. S.Dec.
Sept.
Saturn is a morning star, coming into a better position for
observation. Polar semi-diameter 8 i". P. is — 4°*9; ring
major axis 43J", minor 194". The ring is very widely open.
It is of interest to examine the exact amount of overlap
beyond the planet's pole.
East Elongations of Tethys (every fourth given), 3d 4h-9e,
lld 6h-lw, 18d 7h-4e, 26d 8h-6m; Dione (every third given),
6d llh- le, 15d 4h-2TO, 23d 9h-3»» ; Rhea (every second given),
2d 4h-8-n, lld 5h-7m,20d 6h-6w, 29d 7h-5m. For Titan and
Iapetus E.W. mean East and West Elongations; I. Inferior
(North) Conjunctions, S. Superior (South) ones. Titan, 3d
5h-7e W., 7d 5h-2e S. ; lld 8h-4e E., 15d 8h-4e I., 19d 4h*9d
W., 23d 4h-3e S., 27d 7b-4e E. ; Iapetu , 9* 5h-3w S., 29e
6h-0e E.
Uranus was in opposition on July 29th. Semi-diameter,
13". At end of August, 2° S.E. of p Capricorni.
303
304
KNOWLEDGE.
Table 54. Occupations of stars by the Moon visible at Greenwich.
August, 1913.
Date.
Star's Name.
Magnitude.
Disappearance.
Reappearance.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.
i9«3-
h. m.
h. m.
Sept. 4
BAC 4722
5'5
7 13 '
67"
—
—
„ 6 ...
Lacaille 6719 ...
69
7 13*
63
—
—
,, 6
Stone 8802
7-0
7 49«
89
—
—
„ 8
71 Sagittarii
var.
4 53 '
84
6 13 1
281°
„ 9
BAG 6525
62
7 54 «
121
% 51 1
21 1
„ IO
A Sagittarii
4 9
5 53 «
80
7 He
252
,, 14
h1 Aquarii
5'4
6 2 r
4
6 35 «
302
„ 17
BD+ 9°I42
7'i
—
—
9 29 e
270
„ 19
BD + 15-305
7'5
—
—
2 8 m
180
„ 19
BD+i8°347
6.9
—
—
9 14 '
210
„ 20
BD+i9°432
7-0
—
—
1 39 "'
275
„ 20
47 Arietis
5-8
2 53 '"
116
3 43 »'
193
„ 20
9 Tauri ...
67
—
—
8 58'
219
„ 20
17 Tauri
3 8
11 58'
62
I 9*;«
248
» 21
16 Tauri
3-8
0 17 m
20
I 7 m
289
„ 21
20 Tauri
4'I
0 46 w
28
i 45 m
282
„ 21
7) Tauri ...
30
I 38 m
138
2 2 »<
174
„ 21
24 Tauri
6-8
—
2 8 tit
189
„ 21
BD + 23°54o
70
—
—
2 37 *"
230
„ 21
BAC 1171
6 6
—
—
3 I I VI
221
„ 25
C Geminorum ...
5 '5
2 30 m
48
3 12 111
326
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
The asterisk indicates the day following that given in the date column.
Attention is called to the occultation of the Pleiades on the 21st ; the stars from 17 Tauri to BAC 1171 belong to the group.
Neptune is too near the Sun for convenient observation,
having been in conjunction on July 19th.
Jupiter was in opposition on July 5th. Polar semi-diameter,
19" in mid-September.
Satellite phenomena visible at Greenwich, ld 7h 29m I. Sh.
I., 8h 38m I. Tr. E., 9h 48m I. Sh. E., 10h 31m III. Tr. I.,
10" 47ra 41s IV. Ec. D. ; 2d 7h 3m 46s I. Ec. R. ; 5d 8h 39m 4'
III. Ec. R., llh 15m II. Tr. I.; 7d 10h 50m 6" II. Ec. R„
llh lm I. Oc. D.; 8d 8h 12mI. Tr. I., 9h 25m I. Sh. I., 10h30m
I.Tr. E.; 9d 7h 56m IV. Tr. I., 8h 58m 46" I. Ec. R., 10h 57m
IV. Tr. E.; 12d 7h 37m III. Oc. R., 9h 25m 32s III. Ec. D. ;
14d 8h 4m II. Oc. D. ; 15d 10h 5m I. Tr. I. ; 16d 7" 21m I. Oc.
D., 8h 22m II. Sh. E. ; 17d 6h 51m I. Tr. E., 8h 8m I. Sh. E. ;
Table 55. Non-Algol Stars.
Star.
Right Ascension-
Declination.
Magnitudes.
Period.
Date of Maximum.
h. m.
d.
RU Aquilae ...
20 9
+ 12 '7
7-9 to 14
276
Aug. 22.
R Sagittae
20 10
+ 16 -5
8'5 to 10
70-6
July 20, Sep. 29.
AI Cygni
20 28
+ 32-2
8'6to 9-7
■73
Aug. 27.
V Cygni
20 38
+ 47 -8
6-8 to 14
418
June 29.
T Aquarii ... ...
20 45
-5'5
6'8 to 13
202-7
July 30.
R Vulpeculae...
21 1
+ 23 "5
71 to 13
1368
Aug. 30.
T Cephei
21 8
+ 68 -2
52 to II
387
Oct. 24.
SW Pegasi
21 18
+ 21 -6
87 to ?
175
July 10.
YY Cygni
21 19
+ 42 -o
8510 95
378
Sep. 29.
S Cephei
21 36
+ 78 -2
70 to 13
486
lune 24.
V Pegasi
21 57
+ 5'7
7-8 to 14
303
"Sep. 8.
X Aquarii
22 14
— 21 -3
7-6 to 11
3'5
July 31.
TX Pegasi
22 14
+ 13 '2
8-5 to 9'2
123
July 20, Nov. 20.
S Lacertae ...
22 25
+ 39-8
8-o to 12- 5
237-5
July 29.
R Lacertae ... .."
22 39
+ 41 '9
8-3 to 139
299-8
July 1.
U Lacertae
22 44
+ 54 '7
8-5 to 9-1
659
July 5.
S Aquarii .. ...
22 52
-20 -8
8-o to 14- 5
279-7
July 25.
SS Andromedae
23 8
+ 52 '4
8-9 to 96
165-8
Aug. 5.
TY Andromedae
23 10
+ 40-3
8-2 to 9- 6
144
Oct. 19.
W Pegasi
23 15
+ 25 -8
7 to 13
3426
Aug. 13.
S Pegasi ...
23 16
+ 8-4
7 3 to 13- 1
3I7-5
Aug. 10
R Aquarii
23 39
-15-8
60 to io- 8
387-16
Oct. 6.
V Cephei
23 52
+ 82 -7
6' 2 to 70
362
Nov 20.
R Cassiopeiae...
23 54
+ 50 -9
48 to 13- 2
431°
July 21.
Y Cassiopeiae
23 59
+ 55 2
8-4 to 13.9
410
Nov. 22.
(3 Lyrae minima Sept. 5d 2hm, 17d midnight, 30d 10he, Period 12d 21 -8h.
Algol minima Sept. 3d 0h llm;», 5d 9h0me, 23d lh 54mm, 25d 10h 43me, 28* 7h 32me, Period 2d
20 -8h
August, 1913.
KNOWLEDGE.
305
18d 8h 16"' 58s IV. Ec. R. ; 19d 8h 10m III. Oc. D. ; 23d 6h 36m
III. Sh. E., 8h 5m II. Sh. I., 8h 22m II. Tr. E., 9h 15m I. Oc.
D.; 24" 6h 27m I. Tr. I., 7h 45m I. Sh. I. 8h 45m I. Tr. E.,
10h 4m I. Sh. E. ; 25d 7h 17m 37" I. Ec. R. ; 30d 7" llm III. Sh.
I., 8h 5m II. Tr. I. All these are in the evening hours, the
planet setting before midnight.
Table 56.
Day.
West.
I
East
Day.
West.
East.
SeD. I
O
342
Sep. 16
432
O
I*
,. 2
32
O
14
„ 17
3241
O
.. 3
321
O
4
„ 18
3
O
l*
.. 4
3
U
124
„ 19
13
O
24
>, 5
1
U
24
3*
,, 20
2
O
134
., 6
2
0
134
,, 21
12
O
34
.. 7
1
u
34
2«
,, 22
O
1324
,, *>
0
1324
.. 23
31
0
4
., 9
32
0
I*
.. 24
32
0
4
,. io
3421
0
.. 25
3
O
124
,, II
43
0
12
„ 26
134
O
2
., 12
41
0
32
.. 27
42
0
13
» ii
42
0
13
„ 28
412
O
3
,, 14
412
0
j
„ 29
4
O
123
M 15
4
0
132
„ 30
413
O
2
last year are again available, and readers are referred to the
corresponding month, of last year.
Variable Stars.— Tables of these will be given each
month ; the range of R.A. will be made four hours, of which two
hours will overlap with the following one. Thus the present
list includes R.A. 20h to 0h , next month 22h to 2h , and so on.
Meteor Showers (from Mr. Denning's List) : —
Configuration at 81' c for an inverting telescope.
Double Stars and Clusters. — The tables of these given
Radiant.
Date.
R.A.
1
Dec.
June to Sep. .
335
+
57
Swift.
July 25 to
Sept. 15
48
+
43
Swift, streaks.
[uly to Sept. .
335
+
73
Swift, short.
Julv to Oct. ...
355
+
72
Swift, short.
Aug. to Sept. .
353
—
11
Rather slow.
346
0
Slow.
Aug. to Oct. 2.
74
+
42
Swift, streaks.
,, to Sept...
63
+
22
Swift, streaks.
Sep. S-15 ...
62
-t-
35
Swift, streaks.
„ 6-17 ...
106
+
52
Swift, streaks.
.1 lS-24 •
14
+
6
Slow.
,, 21
31
+
19
Slow, trains.
,, 27-3° ■•■
4
+
28
Slow.
„ 28 to
Oct 9
320
+
40
Slow, small.
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
THE LIGHT- VARIATION OF EROS.— It will be
remembered that at the time of the near approach of Eros at
the end of 1910 and beginning of 1911 a large variation was •
detected in its brightness ; there was a question whether the
period was five hours or two and a half hours ; it appears that
the full period is five hours, but that it is made up of a double
wave with unequal maxima, like some variables (Beta Lyrae
has the maxima equal, the minima unequal). At the opposition
of 1903 Eros was far south, and Professor S. Bailey made
most careful observations on the variability at the Arequipa
Observatory. The visual and photographic methods con-
firmed each other, and showed that the five-hour period is
correct ; the exact value is 0-2196 day, but this has not been
corrected for the changing position of the planet. Taking the
minimum brightness as zero, the following tables give the
excess of brightness (in stellar magnitudes) over minimum
light at intervals of one-twenty-fourth of the period, beginning
at principal maximum. The upper set is derived from the
visual measures, the lower from the photographic : —
•63, -57, -44, -27, -10, -01, -00, '06, -19, -34, -47, -55, -56
•50, -40, -29, -14, -02, -00, -07, -22, -39, -53, -61.
•51, -47, -39, -28, -15, -05, -00, -00, -07, -16, -29, -38, -43,
•43, -37, -29, -16, -05, -00, -00, -07, >21, -36, -47.
The two curves are in good agreement, and show a range of
fully half a magnitude. The maxima differ by -07; the reality
of the double maximum is probable, but it appears possible
that there is really only a single wave with half the period.
The most probable cause of the variation seems to be
irregular shape of the planet. In such a tiny body gravity is
very weak, and insufficient to form a regular shape. This
seems more likely than the suggestion made by Professor
Turner that it may have spots on its surface of very different
albedoes. On such a tiny world anything in the nature of cloud
or snow is out of the question, for it could not retain an
atmosphere. Also organic rocks like chalk are excluded. It
seems not impossible that at the near approach of 1931 our
giant telescopes may be able to see Eros as a tiny disc (it
should be quite half a second in diameter) and detect any
notable departure from roundness ; double stars half a second
apart are easily separated in large instruments.
There is no reason to think that Eros is the only small
planet whose shape is irregular — many have therefore been
observed at Arequipa for variability. Three gave definite
light-curves: Sirona has a period of 0d,403, range one-half
magnitude; Celuta period 0-364, range one-half magnitude;
Tercidina period 0d,366, range one-half magnitude; its
variation had already been detected by Wolf and Wendell.
Variation was suspected in Hecuba and Urania, but not
fully established. It would seem that the asteroids as a
class have pretty rapid rotation from the periods of those
that vary.
THE WORK OF HARVARD OBSERVATORY.— We
had the pleasure of hearing both Professor E. C. Pickering
and Miss Cannon at the meetings of the R.A.S. and the B.A.A.
in June, and we formed some idea of the immense scale of
their work. Miss Cannon is directing the preparation of a
catalogue of the spectra of one hundred thousand stars,
which will be practically exhaustive down to magnitude 8, and
will contain many fainter stars. This is, of course, made from
photographs taken with a prismatic camera ; it would be out of
the question to obtain so many spectra with a slit spectro-
scope; the latter is, of course, better for large-scale spectra of
bright stars, or for motion in the line of sight, which can only
be deduced in an indirect and unsatisfactory way from the
prismatic camera. This, however, gives a considerable amount
of detail even with faint stars, and wave-lengths of lines can
be deduced differentially. Miss Cannon is so intimately
acquainted with all the types of spectra and their subdivisions
that she can assign them to their different classes with great
rapidity ; subsequently her assistants identify the stars and
prepare the catalogue. No fewer than fifteen Novae were
discovered at Harvard by their spectra, ten by the late Mrs.
Fleming. Many other stars having bright lines in their
spectra have been discovered. Professor Pickering states that
with a slit-spectroscope only about two per cent, of the stars'
306
KNOWLEDGE.
August, 1913.
light is utilised, as atmospheric unsteadiness continually moves
its image off the slit. With the prism before the object-glass
there is little loss of light, no guiding is required ; the spectra
are given any desired width by allowing them to trail on the
plate.
APPEAL FOR MORE VOLUNTEERS FOR OBSER-
VATION OF VARIABLE STARS.— The June number of
Publications of the Astronomical Society of the Pacific
has an article on this subject by Mr. E. Gray. He points
out what a suitable field this is for amateurs with a small
equipment ; a good binocular suffices to observe the brighter
variables, while a very large field of work is open to the
possessor of a three-inch telescope : it need not be equatorially
mounted, though if not it is necessary to commit to memory
the field surrounding each star studied, so as to be able to
identify it without loss of time. For the brighter variables the
observer can make sketches of the fields for himself ; for the
fainter ones he should procure Father Hagen's Atlas. The
article quotes the case of an observer who had only a three-
inch on a tripod stand who was able to observe twenty-six
variables on one evening and to finish work at 8.50 p.m.
There is the charm of uncertainty about this work, for while
some of the stars are regular, others are subject to large
irregularities, and there is the possibility that assiduous work
may find the law of these fluctuations. X Monocerotis is
quoted as a typical star for which more observers are needed
to follow it through all its stages (it does not go below the
tenth magnitude). Beginners are more likely to persevere if
they take up work that they know is of real utility than if
they merely do aimless star-gazing. A further attraction is
added to this field of work by the rich red colour of many
of the stars.
THE PLANET ALBERT. — The same publication contains
an account of Dr. Haynes's work on this planet (better known
as MT). He is taking the three undoubted observations of
1911, October 3rd, 4th, and 11th, and combining them one
by one with each of the other eight doubtful places, so as to
get a series of orbits one of which is presumably right. Search
will be made in all possible positions when a favourable
opposition recurs. The planet was in opposition last spring,
but only of magnitude 19 or 20. Search was, however, made
with the Crossley Reflector at Lick, and three faint planets
found, but it appeared that none of them could be Albert.
I am glad to note that Dr. Haynes has received the degree
of Doctor of Philosophy in the University of California in
recognition of this work.
THE TROJAN GROUP OF PLANETS.— The same
magazine has an article on this group by Dr. S. Einarsson.
They nearly conform to the equilateral configuration with the
Sun and Jupiter, which Laplace showed to be an exact
solution of the three-body problem. The present paper shows
that it is both simpler and more accurate to deal with the
motion on this, basis from the first than to treat Jupiter's
action as a mere perturbation.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
THE "AFTER-RIPENING" OF SEEDS. — In many
cases seeds require a long time for germination, usually
owing to the exclusion of water or of oxygen by the seed-
coat. After excluding such cases, however, there are some
plants left in which the seed does not grow, even when the
coat has been removed and the embryo put in good germinating
conditions, until a certain period has elapsed, during which
some change is evidently taking place in the embryo. To
such cases the term " after-ripening " is strictly applied, and
Miss S. Eckerson has just made a careful study of this
phenomenon (Bot. Gaz., Vol. LV). It has been found that
seeds of various pines show a delay in germination of as much
as two years, while those of ash sown in spring do not
germinate until the following spring. In the latter case the
embryo in the mature seed occupies about half the space
within the endosperm, the rest being occupied by a muci-
laginous substance ; during the year that the seed lies in the
ground the embryo grows in length and fills the seed-coat ;
hence a period of growth is necessary before germination.
The authoress has studied the delayed germination or
" after-ripening "of the hawthorn (several speciesof Crataegus).
She finds that food is stored in the embryo in the form of
fatty oil ; lecithin is also present, but there is no starch or
sugar. The reaction of the cotyledons is acid, but the
hypocotyl is slightly alkaline. During the after-ripening period
there is a series of metabolic changes in the embryo, beginning
with increased acidity, and correlated with this there is an
increased water-absorbing power, and also an increase in the
activity of the ferments catalase and peroxidase. Near the
end of this period there is a sudden increase in the acidity and
in the water content ; here oxidase first appears. All of these
increase until the hypocotyl is three to five centimetres long ;
then fats decrease and sugar appears, while hydrocyanic acid
is present in the cotyledons. The after-ripening period can
be greatly shortened by treating the embryo with dilute acids ;
the water- holding power, the acidity, and the amount of
peroxidase increase much more rapidly, and oxidase appears
much earlier, than in untreated embryos. Apparently there
is a correlation between the acidity of the hypocotyl of
Crataegus, its water-absorbing power, production of ferments,
and germinating power. Whether the acidity is causal or
merely correlative is not known, though there is some evidence
that it is causal — for instance, it has been found to lead to the
liberation of ferments, and to increase the water-absorbing
power of colloids.
BACTERIAL NODULES ON LEAVES— All students
of plant life are doubtless familiar with the remarkable
nodules found on the roots of Leguminosae and a few other
plants (Aluus, Myrica, Podocarpus, and so on) and con-
taining bacteria which fix free atmospheric nitrogen and thus
supply the " host " plant with nitrogenous food. Faber
(Jahrb. f. wiss. Bot., 1912) describes an interesting and
unexpected symbiosis of a similar kind which he has dis-
covered in two tropical genera (Pavetta and Psychotria)
belonging to the Rubiaceae; but here the nodules are developed
on the leaves instead of the roots. The bacteria have the
same power of nitrogen fixation as those in the roots of
Leguminosae. They are already present in the unopened
bud, lying in the cavity formed by the stipules of the leaf, and
they enter the leaves themselves by way of the stomata,
collecting in the air cavity just below a stoma and multiplying
so as to disturb the shape of the surrounding cells of the leaf,
which appear to be stimulated to vigorous division, resulting in
the formation of a mass of small-celled tissue. In this tissue
there are relatively large intercellular spaces, and in these the
bacteria grow, though without apparently injuring the cells.
After the bacteria have entered and set up the formation of
the nodule or "gall," the stoma becomes occluded, shutting
them in ; the plant has, so to speak, swallowed the bacteria.
The tissue in the swelling contains abundant chlorophyll and
starch grains, but when the nodule is fully formed the starch
disappears and is replaced by reducing sugar, evidently formed
by fermentation of the starch. Finally, towards the close
of the leaf's life the bacteria have largely disappeared from
the intercellular spaces and the cells again contain abundant
starch ; hence the food apparently serves for the nutrition
of the bacteria — as one might say, in return for the service
rendered by them to the plant in supplying the latter with
nitrogenous compounds manufactured from the atmosphere.
In a variegated form of Pavetta indica these remarkable leaf
nodules are conspicuous as green swellings on the otherwise
white leaf.
The author believes that this represents an ideal case of
symbiosis between bacteria and higher, plants, though the
latter gets the better exchange, since ultimately the cells of
the leaf, whether or not they actually cause the death of the
bacteria, at any rate absorb their dead remains ; the walls of
the bacterial cells become slimy, and eventually they disappear.
The bacteria, which closely resemble the tubercle bacillus,
occur in the seed, lying between the embryo and the endosperm,
August. 1913.
KNOWLEDGE.
307
and after germination they are found occupying the growing
tip of the young shoot, so that the relationship between the
bacteria and the higher plant is extremely intimate and begins
at a very early stage. The author killed the bacteria with
hot water without injuring the embryo, and found that the
young plants thus sterilised, or freed from bacteria, grew very
slowly and had small leaves as compared with normal or
infected plants. Sand cultures of sterilised and unsterilised
seedlings showed that the former died in the absence of a
supply of nitrogenous food materials, while the latter grew
quite well. Precautions were taken in these cultures to
exclude other micro-organisms.
CYTOLOGY OF BACTERIA.— In a long paper on the
cytology of bacteria, Dobell (Q.J.M.S., Vol. LVI) prefaces his
own observations by a useful and interesting summary of
previous work on the structure of bacteria, with special
reference to the methods of fixation and staining used by the
various investigators and to their conclusions concerning the
presence or absence of a nucleus in these organisms. He
examined a large number of forms, obtained from the
intestines of various animals, and arrived at the following
conclusions. All bacteria which have been adequately
investigated have a nucleus; but the form of the nucleus is
variable, not only in different bacteria, but also at different
periods in the life-cycle of the same species. The nucleus
may be in the form of a loose system of granules (chromidial
nucleus) ; or of a filament of variable configuration ; or of
one or more relatively large aggregated masses of nuclear
substance ; or of a system of irregularly branched or bent
short strands, rods, or networks ; and probably also in the
vesicular form characteristic of many plants, animals, and
protista. There is no evidence that non-nucleate bacteria
exist. The author considers it highly probable that the
bacteria are in no way a group of simple organisms, but
rather a group displaying a high degree of morphological
differentiation, coupled in many cases with a life-cycle of
considerable complexity.
BIOLOGY OF THE PITCHER-PLANT DISCHIDIA.
— In the genus Dischidia belonging to the Asclepiadaceae
and found in the East Indies as epiphytes climbing by
adventitious roots and having fleshy wax-clad leaves, some
species have, in addition to ordinary leaves, remarkable
pitcher-leaves. Each of these is a pitcher with an incurved
margin and about four inches deep ; but their biology is very
different from that of such pitcher-plants as Nepenthes.
Into the pitcher there grows a root which arises from the
stem or from the leaf-stalk close to the pitcher, and this root
ramifies among the humus and other debris which is apparently
largely carried into the pitcher by ants. The pitcher also
catches rain-water, hence it serves as a humus collector and
water reservoir ; the inner surface is coated with wax, hence
the water cannot be absorbed by the pitcher itself, nor lost
by passing through the walls, but must be absorbed by the
roots; the inner surface of the pitcher also bears stornata, and
doubtless the water-vapour given out through these is con-
densed in the pitcher.
Some further details of the biology of Dischidia have
recently been given by Kerr (Proc. Roy. Dublin Soc, Vol.
XIII) from observations made on the pitcher-bearing species
D. Rafflesiana and on D. nutntnularia in their native
habitat in the jungles of Northern Siani. The plants are
associated with two species of ant (Iridomyrmex
myrttiecodiae, I. cordex). In D. nutntnularia the ants are
found below the leaves, where they form nests of clay and
vegetable debris in which the roots of the Dischidia branch ;
while in D. Rafflesiana the ants make their nests within the
pitchers and plaster clay above the bases of the pitchers and
over the roots. The flowers are pollinated by bees, but the
ants assist in the dispersal of the seeds, removing them for
food — the seeds not eaten germinate along the ants' tracks.
The author concludes that in D. Rafflesiana the pitchers do
not so much store water as serve to economise the water
vapour of transpiration and also provide shelters for ants,
which in return supply the roots with food material.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon), F.I.C.
ARGON AND ITS PLACE IN NATURE.— An outline of
a communication on this subject made by Sir William
Ramsay, to the Chemical Society of Rome, is given in the
Chemical Trade Journal (1913, LII, 595). The experiments
of Professor Collie and Mr. Paterson, which indicated the
formation of helium and neon from hydrogen, have been
repeated and their results confirmed. In the opinion of Sir
William Ramsay dry hydrogen becomes polymerised into
helium, when subjected to the action of cathode rays in a
vacuum tube, while for the production of neon the presence of
oxygen is necessary. This might be derived either from a
trace of moisture or from the bombardment of the glass by the
rays. When the experiment was modified by placing dry
hydrogen in a vacuum tube and passing an electric discharge
for five or six hours between an aluminium cathode and
anode, which were coated with sulphur, argon was produced,
but no trace of helium or neon could be detected. Again,
when the electrodes were coated with selenium instead of
sulphur the gas, after the experiment, showed the character-
istic lines of the krypton spectrum. The three elements
neon, argon, and krypton, the atomic weights of which are in
an ascending scale, have thus apparently been produced from
hydrogen in the presence of oxygen, sulphur, and selenium
respectively — elements which stand in an analogous relation-
ship towards each other.
BIOLOGICAL METHOD OF IDENTIFYING SEEDS.—
The precipitin method of distinguishing between the flesh
and blood of different species of animals was described some
years ago in these columns. In brief, it is based upon the
fact that when the serum of a particular animal is injected
into, say, a rabbit, the serum of the latter becomes
immunised, and when subsequently the rabbit is killed its
serum will give a precipitate with the serum of animals of the
species to which it was rendered immune, but not with the
serum of an animal of another species.
This method has now been successfully applied to the
identification of the seeds of different plants, and an account
of the process devised by Relander is given by Dr. Zade in
' the Bull. Agric. Intel, and of Plant Diseases (1913, IV, 200).
The seeds — wheat, for example — are finely powdered and
extracted with physiological salt solution. The filtered extract
is then injected, in small quantities at intervals of three to ten
days, into a small animal. After a suitable period the blood
serum of this animal is separated and filtered, and the filtrate
tested with a few drops of an extract of the seeds under
examination. If these are of the same kind as the original
seed a precipitate will be produced, whereas the liquid will
remain clear on the addition of extracts from other kinds of
seeds.
By this method Relander obtained a precipitate on
adding extracts of two-rowed barley to the serum of a rabbit
which had been treated with a similar extract, whereas no
precipitate was obtained with extracts of six-rowed barley.
In the same way it was found possible to distinguish between
American, Italian, and Norwegian clover seeds, but Finnish
seed reacted in the same manner as Norwegian seed.
By means of this test it should be practicable to distinguish,
prior to cultivation, between awned and awnless varieties of
wheat, which has hitherto been impossible.
CARBON TETRA-IODI DE.— An iodide of carbon,
CL, which crystallises in ruby-red octahedra, having a
specific gravity of 4-50 at 0° C. was first obtained in 1885 by
the action of iodides upon organic chlorine compounds. The
various reactions by which the tetra-iodide may be prepared
have recently been studied by M. Lantenois (Comptes Rendus,
1913, CLVI, 1385). In order to avoid decomposition of the
product it is necessary not to let the temperature exceed
92° C, and the most satisfactory results have been obtained
by heating lithium chloride for five days at that temperature
with an excess of carbon tetrachloride in a sealed tube. A
pure product could also be prepared by treating iodoform
with a hypochlorite.
308
KNOWLEDGE.
August, 1913.
THE TESTING OF DISINFECTANTS.— The usual
method of testing the value of disinfectants is by comparing
their germicidal powers under standard conditions. This
test, which is commonly known as the Rideal-Walker test, has
recently been subjected to severe criticism by Messrs. Kingzett
and Woodcock (Analyst, 1913, XXXVIII, 190), who cite the
results of experiments to show that the conclusions afforded
by the method are fallacious. For example, they point out
that such powerful chemical agents as nicotine, prussic acid,
and strychnine have little or no action upon the typhoid
bacillus, and that corrosive sublimate has a much lower value
than many coal-tar preparations when tested by the bacterio-
logical method. Again, copper sulphate, which is known to
possess germicidal powers, appears in the light of this test to
be nearly inert. In the opinion of these chemists the Rideal-
Walker test does not take into account variations in the chemical
conditions, and they consider that the only reliable method of
examining disinfectants as a class is to test them for the
particular purposes for which they are required. At the same
time they consider that there is no doubt that for coal-tar
disinfectants the Rideal-Walker test is the best that has yet
been devised.
GEOGRAPHY.
By A. Stevens, M.A., B.Sc.
TOPOGRAPHY, EARTH - MOVEMENTS AND
ISOSTASY — In 1909 the United States Coast and Geodetic
Survey began publication of a series of bulletins* on Isostasy
and the " Anomalies of Gravity," which may be said to
develop along one line the work begun by Bouguer at
Chimborazo, and Maskelyne at Schiehallion. The possibilities
of the principle of isostasy in accounting, in part at least, for
the configuration of the land surface of the globe have been
for some time generally, if darkly, seen. But recently the
subject has been more closely studied, and interesting accurate
determinations have been made by Americans of the degree
to which isostasy obtains, and of the amount of correspondence
between anisostatic conditions and the irregularities of the
terrestrial surface.
In these official publications isostasy was defined, a con-
venient and approximately correct upper limit of isostatic
equilibrium fixed relative to sea-level, and accurate determina-
tions in dynes of the actual intensity of gravity given for
upwards of a hundred and twenty stations in the United
States. For these stations theoretical values of the intensity
were computed by three methods : that of Bouguer, the free-
air method, and a new method due to Hayford, corrections
being applied for topography and compensation. The deficiency
or excess of the observed value over this computed value of
the intensity is called the " anomaly of gravity " for the station.
The United States have been mapped in areas of deficient, or
excessive gravity intensity, and the rate of variation shown by
contouring.
As elsewhere, in the United States there is evidence of
differential vertical movement in the crust of the earth. In
particular the terracing of the Atlantic continental slope, the
submarine canyons and valleys indenting the Atlantic and
Pacific coasts, and the Post-Glacial deformation of the raised
beaches of the great lakes demonstrate extensive subsidence.
Deep valleys cut in the Tertiary deposits of Louisiana to
depths of between two and three thousand feet, which have
been filled with material containing shells representing living
species only, prove recent subsidence at the coast to the
extent of two thousand three hundred feet, increasing inland,
it is estimated, to three thousand feet.
Post-Glacial deformation has frequently been ascribed to the
tendency towards isostatic equilibrium asserting itself on the
disappearance of the ice. J. W. Spencert uses the anomalies
of gravity to show the inadequacy of the weight of the ice"
cap to counterbalance the earth-pressures involved. Gravity
anomalies are worked out by means of constants, due to
Bowie, to equivalent rock -thicknesses, and between the figures
so obtained and the amounts of subsidence and distortion
remarkable correspondence is observed.
Spencer attributes the topographical "bulges" to differential
sinking conditioned by crustal rigidity, and invokes as the
prime cause of movement shrinkage of the earth beneath the
oceans and continents. Thereby continents are raised and
then gradually they sink towards isostatic conditions, pre-
serving on their submerged borders the marks of the
denudation they suffered in the elevated condition. This
explanation, of course, in itself presents little that is new,
and possibly may require revision in the light of work in other
fields of research. But it is important that a definite and
quantitative study of some topographic questions has been
found possible and initiated. Further work, of which we
have a promise, will be looked for with interest.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
AUSTRALITES. — The curious little bodies of volcanic
glass found scattered throughout Australia, and known as
australites, are the subject of a memoir by E. J. Dunn
(Bulletin No. 27, Geological Survey of Victoria). These
bodies are mostly button-shaped, with a central core and
depressed rim. The latter occurs only in the more perfect
forms owing to the accidents of weathering. These discoidal
forms are by far the most abundant ; rarer shapes are elon-
gated cylindrical and dumb-bell shaped ; others are quite
irregular. The material of the australites is acid volcanic
glass, identical in structure and composition with obsidian.
Thin sections show that the australites have good flow-
structures, and have been built up by material which flowed
in from above and around their peripheries.
These bodies are regarded by Mr. Dunn as the blebs or
lower portions of glass bubbles. They are very similar in
form to the drop of water which collects at the base of a soap-
bubble. They are conjectured to have been formed in
volcanoes, and their distribution over Australia is accounted
for by their dispersal through the agency of air-currents. The
bubbles would be blown up to a height of five or six miles
above the volcano, and before their destruction might have
been carried hundreds of miles from their point of origin by
the air-currents of the upper atmosphere. On the bursting
of the bubbles the pendant blebs would fall to the ground,
and would become embedded in whatever formation was then
in process of deposition.
Australites occur in deposits representing a period corre-
sponding with that covered by the last great episode of volcanic
activity in Australia. It is uncertain, however, how far they
extend back into the Tertiary era. They were formerly
regarded as of meteoritic origin ; but this cannot be reconciled
with their chemical composition, which is utterly unlike that
of any meteoritic body, with their symmetrical shapes, and
local distribution.
J. F. Hayford, " The Figure of the Earth and Isostasy from Measurements in the United States'
" (U.S.C. # G. Survey, 1909); J. F. Hayford and W. Bowie, "Effect of Topography and
in 1909 of the Figure of the Earth and Isostasy
Isostatic Compensation upon the Intensity of Gravity " ; W. Bowie
the Intensity of Gravity, Second Paper '
A Supplementary Investigation
1 Effect of Topography and Isostatic Compensation upon
(U.S.C. & G. Survey. 1912).
1 J. W. Spencer, " Relationship between Terrestrial Gravity and Observed Earth Movements in Eastern America," Amcr. four.
Science, June, 1913.
August, 1913.
KNOWLEDGE.
309
METEOROLOGY.
By William Marriott, F.R.Met.Soc.
"THE DOCTOR."— At the June meeting of the Royal
Meteorological Society a paper by Mr. H. W. Braby was read
on the Harmattan Wind of the Guinea Coast, which was
based upon the results of five years' observations made at
Zungeru, in Northern Nigeria. The harmattan blows during
the winter months along the coast of Upper Guinea, from
French Guinea to the Cameroons. It is exceedingly dry and
brings with it fine sand which enters the crevices of doors and
windows, covering everything with a film of dust. The sun
is partially obscured, and distant objects become invisible.
It blows intermittently from November to March, and is,
generally speaking, health-giving, although its extreme dryness
is trying to new residents. It is locally known as " the
doctor."
The harmattan almost invariably blows from the north-
east, a circumstance which justifies the presence of dust
particles brought from the Sahara. In some respects the
wind partakes of the nature of a Fohn. It is exceedingly
dry and blows from elevated to lower regions. Mr. Braby
points out that its direction necessitates there being an area
of high barometric pressure to the north and of low pressure
to the south. The area around the northern tropic, however,
seems scarcely far enough from the equatorial regions to be
the seat of a well-defined winter anticyclonic system, such as
prevails in the interior of Asia at that season. The equatorial
low-pressure belt is, however, now at its southern limit, and
this combined with the somewhat lower winter pressure to the
north appears to be sufficient to establish a north-easterly
wind along the Guinea Coast.
HURRICANES OF THE WEST INDIES.— The opening
of the Panama Canal in the near future will no doubt bring
about a change in the long-established sailing routes and turn
much of the tide of commerce of the Atlantic and the Pacific
towards the Isthmus of Panama. The convergence of new
routes to the Caribbean Sea and the Gulf of Mexico will
necessitate the crossing of a wide area swept at intervals
during several months of the year by the severest type of
storm known to the mariner, viz., the West India hurricane.
With the view of giving information on this subject Professor
O. L. Fassig has tracked all the hurricanes which have
occurred in the West Indies during the thirty-five years 1876-
1910, and the results have been printed in a bulletin published
by the U.S. Weather Bureau.
The hurricane belt may be defined as the area embracing
the Caribbean Sea, the Gulf of Mexico, and the West India
Islands. Within this area the points of origin are distributed
with a fair degree of uniformity, although belts of varying
frequency are clearly discernible. There is a well-marked
main path of greatest frequency through the northern half of the
Caribbean Sea, extending almost due east to west between
the Windward Islands and Jamaica; taking a north-west
crossing through the Yukatan Channel and across the western
end of Cuba, the path recurves in the eastern portion of the
Gulf of Mexico and across the Florida Peninsula into the North
Atlantic, with a north to north-east trend. There is a
secondary path, not so well defined, extending from the
northern group of the Windward Islands in a west-north-west
direction across the Bahama Islands and recurving east of
Florida in the North Atlantic Ocean. Between these two
paths lie the Greater Antilles — Cuba, Jamaica, Haiti, and
Porto Rico. Of these islands Porto Rico and Haiti are
comparatively free from the devastating winds near the
hurricane centres ; the western half of Cuba is crossed in
the recurve of a large percentage of the storms of the
Caribbean Sea, or those of the main branch referred to
above. These two paths coincide very closely with the two
branches of the great equatorial current of the North Atlantic
Ocean, the main stream of which passes through the
Caribbean Sea and the Yukatan Channel into the Gulf of
Mexico and out into the Atlantic again through the narrow
channel between Havana and Key West. Here it meets the
northern branch of the equatorial current, which is more in
the nature of a wide surface drift of equatorial waters passing
through the Bahama group of islands, forming, later in its
course, the eastern portion of the Gulf Stream.
The normal track of hurricanes for the entire season
resembles a parabola in form. The first branch extends in a
direction west by north, between the parallels of 18° and
20° N. lat., to the centre of the hurricane area (23° N. and
70° W.), then north-westward and north; recurving over
Central Florida, the trend is north-eastward over the Atlantic
along the second branch of the parabola.
The geographical centre of origin for the entire season is
just off the north-west coast of Haiti. The average point of
recurve is in the centre of the Florida Peninsula. The
advance of the season is marked by a slight increase in the
latitude of the point of recurve. The movement of hurricane
paths from south to north and return southward coincides
very closely with the movement of the trades and the
equatorial belt of calms.
Conditions favourable for the formation of hurricanes in
the West Indies begin in the month of June, but do not
become well developed until the month of August. From
August to the close of October is the real period for these
storms. The mean daily movement of hurricanes for the
entire season is about three hundred miles, or about 12-5 miles
per hour. After passing the recurve there is a considerable
increase in the velocity, especially in the latter part of the
season. The average period of duration of hurricanes while
within the zone below the latitude of 30° N. is about
six days ; about three days are spent in moving westward
along the storm's path and two days in the recurve. After
the recurve the storm enters into the region of temperate
zone cyclones, and may continue its existence for many days,
sometimes crossing the entire expanse of the North Atlantic
and even into Europe.
HURRICANE, TYPHOON, AND CYCLONE.— These
terms are applied to the same type of storm, but, as Mr. O. L.
Fassig has pointed out in the paper quoted above, they are the
same in essential character. To the meteorologist they are
all " cyclones " or storms in which the surface winds blow
toward a central area of low barometric pressure at angles
varying between 0° and 90°. This broad definition includes
not only the intense storms of the Indian Ocean and the Bay
of Bengal, originally called " cyclones," the hurricanes of the
West Indies, and the typhoons of the Pacific, but also the
temperate-region storms usually referred to as " barometric
depressions," " storm areas," or simply " lows," and the
tornadoes of central valleys of the U.S.A., and waterspouts over
the seas in all parts of the world. In all storms of this class the
surface winds blow more or less spirally inward toward an
area of minimum atmospheric pressure, then upward and out-
ward at elevations varying with the extent and intensity of the
storm. The term " hurricane " is restricted to cyclones which
have their origin and field of action within well-defined limits,
embracing the West Indies and neighbouring waters of the
North Atlantic. The storms occurring in tropical regions of
the Western Pacific are called "typhoons." In the Indian
Ocean they retain the name originally given them by the
early English mariners, namely, cyclones. It is only in
comparatively recent years that the term " cyclone " was given
the broader, and at the same time more technical, definition to
include all so-called " revolving " storms. The temperate-
region cyclone covers a greater area than the tropical
variety, the diameter of a well-developed storm of the middle
latitudes being over one thousand miles, and occasionally
covering more than half the area of the United States ; the
cyclone of the tropics is generally not over three hundred to
four hundred miles in cross-section, but probably penetrates
to a greater height into the atmosphere than the extra-tropical
cyclone. Tropical storms are accompanied by a greater fall
in the barometer, resulting in more destructive winds and
heavier rainfall than in the temperate-region cyclone, where
the barometer falls with a more uniform gradient from the
310
KNOWLEDGE.
Auoust, 1913.
edge of the storm to the centre. In the tropical storm there is
a moderate decrease of pressure to within forty or fifty miles
of the centre, and then a rapid fall, which in exceptional cases
may descend to twenty-eight inches and even less. This
steep-pressure gradient marks the area of the destructive
winds and the excessively heavy rainfall which are character-
istics of the tropical storm.
CLIMATE AND HEALTH.— During last session Mr.
W. Marriott read a paper on " Meteorology and Public
Health " before the Institute of Sanitary Engineers, which
has now been published in their Journal. He showed that a
bracing climate is invigorating and acts as a tonic to the body.
This is due to an open exposure and a good wind or current of
air blowing over the place. This continuous flow of air over
the body removes the moisture from the skin, and so causes a
lowering of the temperature, which in turn produces a crisp
and pleasant feeling. A relaxing climate, on the other hand,
is enervating and causes a languid feeling. This is largely due
to the situation being sheltered, and also to comparatively
little movement of the air. Consequently the moisture from
the skin is not so freely removed as when there is a continuous
flow of air. Again, there is the inland climate and also the
sea-coast or maritime climate. Inland the temperature, as a
rule, is high during the day and low during the night, and so
there is a considerable diurnal range of temperature. Along
the sea-coast the temperature does not rise so high during the
day nor fall so low during the night ; consequently the range
of temperature is less on the coast than it is inland.
Extremes of temperature — hot weather in summer and frost
in winter — cause an increase in the death-rate. In summer
the increase in the number of deaths is due almost entirely to
cases of infantile diarrhoea. In winter the increase in the
number of deaths is due almost entirely to diseases of the
respiratory organs, especially among young children and old
people.
Pneumonia and bronchitis are most prevalent in the colder
months, and generally follow cold, damp weather with marked
changes of temperature, which lower the vitality and are con-
ducive to chills. Severe cold spells are likely to be followed
by an increase of pneumonia, especially among elderly persons
and children.
MICROSCOPY.
By F.R.M.S.
THE APLANATIC AND ACHROMATIC CON-
DENSER AND ITS USE AS AN APERTOMETER.—
The Aplanatic and Achromatic Condenser possesses another
useful quality, inas-
much as it can be
employed as an aper-
tometer. This pro-
perty arises from the
following optical facts.
The iris - diaphragm
being situated near the
lower focal plane of the
condenser, an image
of it is formed thereby
at a distance which
may be equated at
infinity. Of this image
the objective forms
another at its posterior
focus and situated near
the outer surface of the
back lens on the side
towards the eyepiece. The rays of a pencil of light entering
the condenser in a direction parallel to its axis intersect at its
anterior focus. As this is made to coincide approximately
with the lower principal focus of the objective it follows that
the pencil of rays which proceeds from the focus of the
objective will emerge from its posterior focal plane in the
form of a pencil composed of approximately parallel rays.
Figure 339.
The base of the pencil of rays appears on the back lens of the
objective as a bright circle, and hence it will be seen that this
bright circle of light and the image of the iris-diaphragm are
situated more or less in the same plane. The diameter of the
circle of light is governed by the aperture of the objective
which corresponds to an equal angular aperture of the
condenser. The latter again is determined by the opening of
the iris-diaphragm. The aperture of the condenser can be
computed from the diameter of the iris-diaphragm, thus
supplying the requisite datum for determining the aperture of
the objective.
That the condenser may be used in this way as an aperto-
meter is due to the fact that its formula satisfies the sine
condition, and not so much to its spherical and chromatic
correction, the principal effect of the latter being that the
condenser furnishes a more sharply defined image than an
ordinary condenser.
i
The sine condition is expressed by the formula = const.
sine a
In the case of parallel incident light this constant quantity is
numerically equal to the focal length of the condenser, h is
the semi-aperture of the iris-diaphragm, whilst sine a with dry
lenses and m sine a. with immersion lenses represents the
numerical aperture of the condenser. From this it will be
seen that the aperture of the condenser varies directly as the
numerical aperture of the condenser as well as that of the
objective. This simple relation is a convenient circumstance,
inasmuch as the indices corresponding to the numerical
apertures 0-1, 0-2 . . . to 1-3 are separated by uniform
intervals (see Figure 339^.
To calculate and register the scale of apertures become
under these circumstances a very simple matter. When a
preparation lies between the objective and the condenser the
angle by which the rays emerge from the condenser is the
same as that by which they enter the objective ; that is to say,
the angles which determine the aperture of the condenser and
objective remain equal, since the object slide, the cover-glass,
and the interval between the latter and the objective behave
optically as plane and parallel plates. This being so, the
angles of incidence and emergence of a ray passing through
the intervening media are identical so long as the surround-
ing media — in this case air, water, or oil — remain the same.
The aperture maybe determined in the following manner : —
Focus the objective in the usual manner in the plane of the
object, using diffused light ; next remove the eyepiece and,
placing the eye immediately above the tube, view the circle of
light at the back of the objective and open the iris-diaphragm,
the image of which will also be seen in this plane, until its
opening just coincides with the boundary of the circle of light
at the back of the objective. To use the condenser in this
way it is necessary to have the mount of the iris-diaphragm
graduated in terms of the numerical apertures.
It will be admitted that it would be difficult to imagine a
simpler and more inexpensive device for measuring the aper-
ture of lenses, and the manner of using it cannot give the
slightest difficulty. The accuracy of the results is all that could
possibly be desired for any practical purpose. The difference
in the aperture of objectives, as found by this simple method,
and its absolute value, as determined by the most exacting
methods in use, is too insignificant to disclose any appreciable
difference in the light-transmitting and resolving power of
objectives differing to this small extent in their apertures. As
a matter of fact, these discrepancies are no greater than those
unavoidable and invariably existing differences in the in-
dividual objectives of the same denomination arising from
slight variations in the thickness, position, and mounts of the
lenses.
It is no doubt convenient to be able to determine without
trouble and with practically a sufficient degree of accuracy
the aperture of an objective. This, however, is scarcely the
best use to which an apertometer can be put, as it is a far
more important advantage that the apparatus enables the
observer at any instant to ascertain and state numerically the
aperture of direct light at which he is actually working, and
that will give him the best results.
August. 1913.
KNOWLEDGE.
311
The reader need scarcely be reminded of the importance c'
the proper choice of the aperture of the condenser, and to
realise how different are the effects produced by the different
apertures one need only instance the case of Koch's
structural and colour images : both are the result of the same
optical condition — in one case with a contracted diaphragm to
attempt to bring out fine structural details in unstained
preparations, in the other with the condenser opened to its
full extent to show deeply stained bacteria.
A condenser whose aperture can be varied in a numerically
definite manner does away with loose statements to the effect
that this or that investigation should be carried out with the
condenser shut down to one third, a half, two thirds, and so
on. Directions of this kind are far too indefinite, and are not
even applicable to condensers of different maximum apertures.
In future it will be as easy as it will be desirable to specify the
aperture of the condenser among the other particulars relating
to microscopic observations, projection, and photomicrography,
such as the denomination of the lens, its magnification, and
the tarsi has two claws with a caruncle or sucker ; this
caruncle assumes different forms in different species.
They prefer damp places to live in ; that is to say, those
that are not parasitic. They are found under stones, decayed
wood, garden rubbish, stables, under loose bark of trees,
in moss, and I once found a large number in a deserted robin's
nest.
The Gamasoidea is divided into three families — Gamasidae,
Uropodidae and Dermanyssidae. Nathan Banks, the
American writer on mites, gives the following key to the three
families of the Gamasoidea : — -
(1) Parasitic on vertebrates : mandibles fitted for piercing ;
body sometimes constricted. Dermanyssidae.
Free, or attached to insects, rarely on vertebrates, never
on birds. 2.
(2) First pair of legs inserted within the same body-open-
ing as the oral tube : genital apertures surrounded
by the sternum. Uropodidae.
Figure 340.
Gamasus equestris Koch.
Drawn under camera lucida from a
specimen found at Barmouth. $
Figure 341.
Uropodidae.
Drawn from a specimen found in moss
at Sunningdale. Ventral surface of
Cilliba cassidens. ?
Figure 342.
Dermanyssus avium.
Drawn under camera lucida from
specimen from a canary.
the nature of the illumination, time of exposure, and so on.
This will be an easy matter, as the aperture can be read by
the index of the iris-diaphragm.
C. Metz. (Wetzler.)
GAMASOI DEA. — Anotherneglected super-family of mites is
the Gamasoidea, and yet entomologists are continually coining
across specimens, either as messmates or parasites, on various
kinds of insects. Not much notice, however, is taken of thein.
They are more often than not thrown away as a nuisance ; yet
they may be more interesting than their host. The most
commonly known of all the Gamasids is no doubt Gamasus
coleoptratorum and G. crassipes, so often found in large
numbers on the Dor beetle and others. Beetles, however, are
not the only insects on which they are found ; all other sorts of
insects are pressed into their service either to supply them
with nourishment or as a means of getting from one place to
another. One family of the Gamasoidea — the Dermanyssidae
— are all parasitic on warm-blooded animals.
The characteristics of the super-family are — they are without
any visible eyes ; they are mostly pale coloured : being
generally a light brown or fawn colour they have none of the
brilliant reds we find in the Trombidiuins. The bodies are
broad and flat. The skin is mostly smooth and tough, in
some species chitinous only in parts, the other parts being
thinner and paler in colour. The legs have seven segments,
(3) First pair of legs inserted at one side of the mouth
opening, male genital aperture usually on the anterior
margin of sternal plate. Gamasidae.
The Dermanyssidae are all parasitic. The best-known
representative is the red mite, found in such large numbers in
bird-cages and fowl-houses that have not been kept clean.
This bright red colour of the mite (which is commonly known
as Dermanyssus avium Dug.) is due to the amount of blood
which the mite has sucked from its host during the night. In
the daytime, if it can possibly hide away, it is invisible. The
Dermanyssidae is split up into about half a dozen genera.
There are several papers on this family, but I have not heard
of any monograph.
The Uropodidae. — The most striking feature about this
family is that some of its members are found attached to
their host with a connecting filament which De Geer
thought was of the nature of an umbilical cord by
which the mite drew its nourishment. Other naturalists
thought it was a silken cord with which the Uropoda tied
itself to its host to prevent it being brushed off. It has
since been found to be connected with the anus of the
mite, and to be nothing more or less than its consolidated
excrement : this connection the mite can sever at will.
Banks says that these mites so attached are not true
parasites, but that it is a means used by nymphs as u
312
KNOWLEDGE.
August, 1913.
means of migration. This family is divided into about six
genera.
The Gamasidae are the largest family of the three, containing
about twenty genera. A number of papers have been published
in the British Isles on the Gamasoidea in natural history
and microscopical journals. Mr. Michael has given two, if
not more, very interesting ones on the internal anatomy of
Gamasidae and Uropoda; also one on the life-history of
Gamasidae, and in 1888 described one new species. Dr.
George has also described and recorded some rare and
interesting species in The Naturalist from time to time —
three species in particular, of the genus Epicrius. But there
is no monograph on any of the three families yet, neither is
there a Tierreich.
Figures 340-342 will help to convey the general appear ■
ance of each family. But, as Mr. Banks says, the Der-
manyssidae and the Gamasidae are so closely allied by
structure that the parasitic habits are the best character for
separation.
C. D. Soar, F.L.S., F.R.M.S.
QUEKETT MICROSCOPICAL CLUB.— May 28th —
T. A. O'Donohoe read a paper on " Minute Structure of
Coscinodiscus asterotnphalus, Pleurosigma angulatum,
and P. balticum." The object of the paper was to prove
that the " black dot " is the correct image of diatom structure.
Photomicrographs, mostly at X 4000, were shown of fragments
of the diatoms mentioned. When the edge of the fracture was
sharply focused the transparent silex was shown as white
and the perforations as black. On slightly raising the
objective the silex was rendered as black and the perforations
as white. It was therefore thought to be justifiable to relegate
the " white dot " images of diatoms to the abode of Mr.
Nelson's " ghosts."
June 24th. — E. M. Nelson sent a note describing Koristka's
new loup.
H. Sidebottom, contributed a paper on " The Lagenae of
the South-West Pacific." This is part two of a paper
published in the April 1912 issue of the Club Journal.
There was some discussion as to the significance or use
of the very beautiful markings and decorations found
in this and other groups of organisms. The President could
not conceive it possible that the presence or absence of a
minute projection on a sponge spicule, for instance, could
make any difference whatever to the organism, especially as
in the case of the sponge, the spicule is buried in the general
protoplasmic mass of the animal. In the case of f oraminifera
the markings are invisible during life, as they are concealed
under the usual gelatinous mass of exterior protoplasm.
E. M. Nelson described " A new method of measuring the
magnifying power of a microscope." The " constant " of an
eyepiece with a given tube-length is determined. This
" constant " is found by first determining by any of the usual
methods the combined magnifying power of that eyepiece on
the given tube-length with a medium power objective, such as
half-inch. Second, measure the exact diameter of the field by
means of a stage micrometer. The product of these two
quantities is the " constant " of that eyepiece with the
given tube-length. Example — objective one-third of an
inch, eyepiece, compensating X 8, tube-length 170 milli-
metres, measured magnifying power X 280, measured
field 0-023 inch, product is 6-44, which is the "constant"
of that eyepiece for 170-millimetre tube. The power of
any other objective with this eyepiece and tube-length
can be determined by measuring the diameter of its
field with the stage micrometer. The magnifying power
will obviously be the eyepiece " constant " divided by the
diameter of the field (an objective of varying power with a
negative front cannot be measured in this manner). A
number of examples were given. The " constant " may also
be employed for ascertaining the total magnification for any
tube-length. All other conditions being the same, the total
magnification will be proportional to the tube-length used.
PHOTOGRAPHY.
By Edgar Senior.
USE OF GLYCERINE IN DEVELOPING PLATINUM
PRINTS. — As mentioned in last month's notes on platinum
printing, glycerine is of use in the development of these prints,
as when added to the developer it so reduces its rapidity of
action as to enable local development to be carried out with-
out any difficulty. As the sensitive salts with which the paper
is coated are almost insoluble in glycerine, this may be
brushed over the surface of the exposed paper without risk of
injury to the print. A mixture of glycerine and developer
may then be applied with a brush and an over-printed portion
of the subject may be retarded by the application of a
weaker developer, or one containing more glycerine, until the
other parts of the image are sufficiently strong. This method
of treatment lends itself particularly to the production of
vignetting effects on account of the great softening of the
edges that can be obtained. The strength of the solution
employed by different workers varies, but the following will be
found to answer well : —
Oxalate of Potash
Water
Glycerine (pure)
1 ounce
3 ounces
1 ounce
This will form a stock solution which for use may be taken
in the proportion of one part mixed with an equal volume of
water. If preferred, the developing salts may be used in
place of the oxalate, as with a little practice it is quite easy to
control development with either. When the desired result has
been obtained the prints are placed for the required time in
each of the three acid baths, and finally washed and dried,
intensifying under-exposed platinum prints with gold.
Some years ago Mr. Alfred W. Dolland published a
method of strengthening an under-exposed platinum print by
means of a solution of gold chloride applied with glycerine.
The writer tried this at the time with perfect success. The
procedure consists in applying glycerine to the finished print
and then spreading a solution of gold chloride by means of a
piece of cotton-wool or a brush, the strength of the gold
solution which we used being fifteen grains in fifteen drachms
of distilled water. The print rapidly gained in strength,
assuming a fine bluish-black colour, and when the action had
proceeded far enough the print was washed, and an ordinary
amidol developer applied for a few minutes in order to reduce
any remaining gold chloride to the metallic state, when a final
washing completed the operation. We have quite a number
of prints that were treated in this manner, which appear
as fresh as when first produced, and certainly the colour in
many cases produced a more pleasing effect. Platinum prints
may also be intensified by a method, due to Baron Hubl, of
depositing further platinum upon them. In order to employ
this method the following solutions have to be made up : —
Sodium Formate ...
Water
Platinum Tetrachloride
Water
48 grains
1 ounce
10 grains
1 ounce
For use fifteen minims of each of the above are taken and
made up to two ounces by the addition of water. The print
is placed in a flat dish and the solution is poured over the
dish, which is kept rocking until the desired effect is seen in
the print, when the latter is washed and dried.
WARM TONES IN PLATINUM PRINTS.— Various
substances have from time to time been recommended as
additions to the developer in order to vary the colour of a
platinum print, but the one most generally employed is
mercuric chloride, as by its means, together with variations in
the temperature of the developer, tones ranging from warm
black to sepia are readily obtainable. Numerous formulae for
August, 1913.
KNOWLEDGE.
313
use in the production of these tones have been given, a' though
the following is perhaps as satisfactory as any : —
Mercuric Chloride ...
Potassium Oxalate...
Potassium Phosphate
Water
3 grains
48 „
48 „
1 ounce
The temperature at which the prints are developed ranges
from 653 to 170° F., according as a warm black or one
approaching sepia is desired. When warm tones are obtained
the gradation is usually much softer than that of a black
print from the same negative ; there is therefore a tendency
to general flatness in some cases. When this is the case the
results may often be improved by the addition of about five
minims of a two per cent, solution of potassium bichromate to
each ounce of developer. As special paper is, however, made
by the Platinotype Company and others for obtaining sepia
prints, this should be employed, taking special care to protect
the same during examination of the printing from the action of
weak light as much as possible ; and as these prints, unlike
the black one, are likely to be affected by light when in the
acid baths a more subdued light should be employed during
this stage of the operation as well.
SECTOR SHUTTERS.— We have received a copy of a
paper read at the Optical Convention on June 20th, 1912, by
Cyril F. Lan-Davis, F.R.P.S.,on the subject of sector shutters.
The author, in dealing with the number of leaves
comprised in shutters of this type, and showing that the
position of the pivot does not affect the ratio of the
total diameter of the shutter to its opening diameter,
proceeds to discuss the effect that the shape of the leaves, as
well as their number, has on the shutters' efficiency, showing
by means of diagrams that an alteration in the form of the
leaves as well as a reduction in their number results in an
additional area being uncovered for equal partial central
openings in the shutter. In doing this comparison is drawn
between a ten-leaved shutter of the usual iris form, which
opens in an expanding circle from its centre to edge (so that
the amount of light transmitted by the margin is very small
indeed), and one having two leaves only, which opens in a
broad band that rapidly expands to the full circle. A shutter
of this kind would also possess the further advantage that
it could be made smaller, as the ratio of the total diameter
to the aperture is only 2-1. Although shutters of this type
are not yet on the market, we believe Messrs. J. H. Dallmeyer,
Ltd., are making arrangements for their manufacture. We
have received from Messrs. Wratten & Wainwright, Ltd.,
several of their booklets dealing with the subject of
orthochromatic photography and the use of light filters for
special purposes, such as photo micrography, and in the
illumination of the dark room. We may mention in con-
nection with our notes in the June issue, dealing with the
testing of dark-room light filters, that the firm make quite a
number of special screens for this purpose, which are
scientifically tested, and may therefore be relied upon to
afford a perfectly safe light for use during the manipulation of
the particular kind of plate " or sensitive surface " that they
are supplied for use with. While reserving any further remarks
for some future occasion, we may say that the name of
Wratten & Wainwright is always a sufficient guarantee of
the excellence of any product issued by them.
PHYSICS.
By Alfred C. Egerton, B.Sc.
Xs? — Professor Sir J. J. Thomson, O.M., gave the Bakerian
Lecture to the Royal Society on May 22nd. In the course of
an account of his recent experiments, he surmised that a gas
exists, which he terms, somewhat mysteriously, Xa. When
the positive rays are allowed to stream back through the hole
in a hollow cylindrical cathode in a vacuum tube, through
which an electric discharge is passed, they ionise the gas
through which they pass. The rays produce a number of
differently electrified gas particles ; they give rise to : —
(i) Atoms with one unit positive charge of electricity,
(ii) Molecules with one unit positive charge,
(iii) Multiple charged atoms,
(iv) Atoms with one negative charge,
(v) Molecules with one negative charge,
and when the discharge is passed through air at very low
pressure, since oxygen, nitrogen, argon, carbon monoxide and
carbon dioxide, and hydrogen (from water vapour) are present,
and each of them may be split up in the above ways, the
character of the gas evidently becomes somewhat complicated.
Nevertheless, by submitting the gas to magnetic and electric
fields, the charged particles can be identified from the position
they occupy on a suitably placed screen or photographic
plate, when fields of known strength are applied ; their
mass can then be calculated. By such means there is found
in the gas of tubes in which cathode rays are allowed to
bombard against solids, particles which consist either of
carbon with four charges of electricity or a substance of
atomic weight 3 with a single charge — this latter is the
substance to which Sir J. J. Thomson assigns the name X8,
because it has not itself been isolated yet in the free state,
and because it should have atomic weight 3. The reasons
given f:>r considering that it is not carbon with four charges
are that it can pass over red-hot copper oxide and then over
potash without being absorbed, it is not changed when sparked
with excess of oxygen, it can pass over metallic sodium, it is
not condensed by liquid air, but is absorbed by charcoal
cooled with liquid air, while it combines with mercury vapour
in presence of the electric discharge, and also to some extent
with red-hot copper.
It will be very interesting if this gas can be caught and
examined ; a new gas a little heavier than hydrogen and
lighter than helium may explain much that is not yet under-
stood.
NOMENCLATURE OF RADIOACTIVE
SUBSTANCES. — A little while back an international
committee assembled in order to discuss matters connected
with radioactivity ; one question was the standardisation of
radioactive substances, and in order to be able to refer such
substances to a definite standard it was settled that Mme.
Curie should prepare a solution containing a known amount
of pure radium, the unit of radioactivity so obtained being
called a " curie." Another question was the nomenclature of
radioactive substances ; there are three main groups of radio-
active substances — the radium, the thorium, and the actinium
series. Hitherto, as the separate products of these three
series have been discovered, it has been usual to distinguish
them by consecutive letters of the alphabet, but sometimes
when such names have been settled a product is subsequently
found which lies between two such consecutive letters, e.g.,
thorium Ci and Ca. The question of the nomenclature of
these many products was therefore postponed till such a time
as it should become certain that no more intermediate products
are present to be discovered. However, it is unsatisfactory that
the matter was left in so chaotic a state as it is at present ;
for in different journals, or indeed often in the same paper, the
same product is given more than one name.
There are two ways open — either each product should be
given a definite name as is the custom is for the ordinary
elements, or some elastic system should be devised which
would not only allow for the discovery of new products, but
would also give an idea of the properties of the separate
products. The former system has been favoured by Sir
William Ramsay in naming radium emanation "niton,"
Professor N. Campbell has advocated the other way.
In chemistry organic compounds are named in such a way
that the chemist can tell from the name of the substance
many of its properties, and also its relationships with other
substances; for instance, o naphthylamine signifies that the
substance contains an NH2 group in a particular position in
the naphthalene molecule. It should be possible to devise a
system of nomenclature of radioactive substances from which
it would be possible to tell the main properties of the
substance. The nature of the rays should be prefixed to the
314
KNOWLEDGE.
August, 1913.
name, the number of the product in its series should be
included (for knowing this and the rays given by the product,
the position of the element in the periodic table, and hence its
chemical properties, would be known), and the series to which
the product belongs should be the root of the name. It is
probable that most of the changes, which give off a or P rays,
have now been discovered, and in order to allow for rayless
changes where there is no change of mass of the atom but
only a difference in configuration the method used in organic
chemistry to describe different isomerides (ortho, meta, and
para, and so on) might be imitated.
It is to be hoped that before long the radioactive substances
will be satisfactorily named.
THE MERCURY VAPOUR LAMP.— The Cooper Hewitt
mercury vapour lamp has been so improved that the great
objection, viz., the peculiar colour of the light, can now be
overcome. The inventor has succeeded in this by placing a
celluloid film stained with rhodamine behind the mercury
vapour which is giving out light. The rhodamine fluoresces
with a red colour, that is to say, the rhodamine is so stimulated
by the violet radiations of the mercury vapour that it gives
out rays of its own, which are most intense in the red. The
resulting luminosity makes a fairly good imitation of daylight.
Professor Wood has noticed that when such a stained
fluorescent film is backed by white paper or porcelain the
luminosity is much greater than when backed by a silvered
surface, the reason being that only part of the fluorescent
radiation emerges from the film : the rest is internally reflected
and does not get out, unless a scattering reflector, such as a
matt white surface, is placed behind. The effect is somewhat
striking, and a considerable loss of fluorescent radiation is
shown often to occur owing to internal reflection.
The "neon" light, devised by M. Claude, which has the
similar advantage of the mercury vapour lamp in being very
economical of current, also has the disadvantage of giving rise
to a light deficient in certain colours ; the light is rich in red,
but deficient in green and violet. M. Claude has been able
to combine his lamp with the mercury vapour lamp and over-
comes this difficulty. The mercury vapour lamp works with a
low voltage current, while the neon light is worked by a
current of high voltage and frequency. All the same,
M. Claude has succeeded in his most recent type of lamp in
combining the two quite satisfactorily.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A., LL.D.
RESPIRATION IN THE WATER BOATMAN.— A care-
ful study of the process of respiration in this well-known insect
(Notonecta), which rows on the surface of the water, has con-
vinced Frank Brocher that in ordinary circumstances, at the
surface, only the seventh abdominal stigmata are used, both
for inspiration and expiration. When the water boatman has
finished taking in air, and is about to dive, it makes more
energetic expirations, and expels by all its stigmata the excess
of air which it has in its tracheal system. This expelled air
spreads round the body, to which a portion remains adherent,
while another portion returns to the atmosphere or is
entangled in bubbles about the abdomen.
THE CIGARETTE BEETLE.— Mr. Charles R. Jones
has made an important study of the cigarette beetle (Lasio-
derma serricorne) in the Philippine Islands. It has been
prominent for many years as a destroyer of stored vegetable
products, and is one of the worst pests of the tobacco
industry. All the principal tropical and subtropical tobacco-
producing districts abound with it. The eggs are laid in small
folds in the dried tobacco, e.g., within the open tip of the
cigar or cigarette, or under the overlapping edges of the
wrapper. The larva, which is less than a millimetre in
length to begin with, eats small cylindrical galleries in the
tobacco, especially in the higher-grade tobacco. There is a
little Clerid beetle which feeds ravenously, both in its larval
and adult stages, upon the larvae and pupae of the cigarette
beetles, and acts as a useful check. It has been shown by
careful experiments that the cigarette bettle can be absolutely
controlled, without affecting the tobacco, by fumigations of
carbon bisulphide and hydrocyanic gas, and by using high and
low temperatures.
FUNCTIONAL TEETH IN UPPER JAW OF SPERM
WHALE. — It has been regarded as one of the characteristics
of the Physeteridae — -the sperm whale or Cachalot family —
that functional teeth are confined to the lower jaw. In the
sperm whale, indeed, it is well known that numerous rudi-
mentary teeth occur in the upper jaw ; but these have been
held to be relatively small, embedded in the gum so that they
do not reach the surface, and necessarily, therefore, altogether
functionless. It is recorded, however, by Messrs. James
Ritchie and A. J. H. Edwards that two out of seven
specimens examined at Bunaveneader in Harris bore visible
exposed teeth in the upper jaw. They lay in a row along
a well-defined groove running the length of the jaw on the
inner side of the depressions caused by the mandibular teeth.
There were about a score, each eleven centimetres long, all
but the tip embedded in the gum, far removed from the
maxillary bones. The worn and scratched surface afforded
proof of actual use.
LARGEST AND STATELIEST OF BRITISH
COELENTERATA. — These words are applied by Professor
Herdman to the giant sea-pen, Funiculina quadrangttlaris,
which occurs abundantly in certain limited localities on the
west coast of Scotland. There appear to be " forests " of
them — flexible unbranched colonies fixed in the mud and
rising gracefully into the water. The finest specimen obtained
in 1912 was sixty-two inches in height, and several were about
five feet. Sir Wyville Thomson referred long ago to their
" pale lilac phosphorescence"; Professor Herdman notes their
"' pale translucent rosy tint." ■
SOLAR DISTURBANCES DURING JUNE, 1913
By FRANK C. DENNETT.
There is very little to record by way of disturbance on the
Sun during June, notwithstanding that the disc has been
telescopically examined every day. The falling off of activity
has been as marked as that at the beginning of 1912.
On the 1st, 4th and 8th there were traces of tiny dark
spots, but these were not sufficiently evident to have their
positions measured.
Even faculae have been comparatively few and far between.
On the 4th, minute faculae were visible within a few degrees
of both the South and North Poles. On the 14th a small
facula was situated Longitude 69° and Latitude 23° N., there-
fore approaching the North -Western limb. There was a pale
faculic patch on the 28th in Longitude 245°, Latitude 29° S.,
and so nearing the South-Western limb. Other pale faculae
were seen North-East on the 4th, 5th, 7th and 8th; South-
west on the 8th; South-East on the 7th and 8th ; and near the
centre of the disc on the 4th and 5th.
Whilst looking at the projected image of the Sun upon the
focusing ground glass of the 4-inch photo - heliograph,
formerly in use at Greenwich Observatory, when only one
small spotlet was visible, a visitor was heard to remark that
he was unaware the Sun ever had so few spots as one. But
frequently of late the disc has presented a complete blank.
By the kindness of the Astronomer- Royal we are enabled to
reproduce a print from the original negative of the Sun taken
at the Cape of Good Hope on the morning of April 22nd, 1913,
when the disc was devoid of all disturbance except a very
small group of faculae near the N.E. limb (see Figure 343
and Figure 344 given for comparison).
The observers were Messrs. J. McIIarg, A. A. Buss, E. E.
Peacock, J. C. Simpson and F. C. Dennett.
August, 1913.
KNOWLEDGE.
315
Figure 343.
The Sun practically devoid of all disturbance.
Reproduced by the kindness of the Astronomer- Royal from a print from the original negative of a photograph taken at the
Cape of Good Hope on the morning of April 22nd, 1913.
316
KNOWLEDGE.
August, 1913.
Figure 3-14.
A greatly disturbed Sun.
The Astronomer- Royal has kindly permitted us to reproduce the photograph of the Sun taken on August 8th, 1893, only a
short time before the maximum activity. The great spot group is over 100,000 miles at its greatest diameter, and the
longer group on the other side of the equator nearly 130,000 miles in length. This picture presents a striking contrast
to Figure 343.
PLANT PROTECTION.*
Of the numerous crusades that are being carried on
against the different evils that are recognised as rife
to-day, such as the killing of birds for plumage, the
inhumane slaughter of animals, the preservation of
ancient buildings, and so on, none are of more
importance than the one directed towards the
preservation of wild plants.
The man in the street thinks, when he reads in the
press that a hawker has been fined for selling ferns
that have been carted wholesale from the woods and
lanes, that that is the only cause of the extermination
of beautiful wild flowers and ferns from the outskirts
of large towns, spots that, maybe, he has known in
his youth as a veritable paradise.
But though this is a prevalent notion it is far
from being the truth, and, as everyone knows, a
half-truth is often worse than a lie. The publications
cited show that there are numerous and widespread
other causes at work, some, such as smoke, tree-
felling, golf-links — to mention only a few — equally
powerful in exterminating plants. Mr. Horwood has
collected information on a systematic plan from every
county in the British Isles, and is able to point to
some sixty causes at work in diminishing plants in
particular spots or exterminating them entirely.
As Recorder of the Plant Protection Section of
the Selborne Society (with Dr. Rendle as Chairman,
and an influential Committee), Mr. Horwood describes
the work of that body already accomplished since
its formation in 1910. Not least in this direction is
the publication of the leaflets* issued to the public
and to schools, endeavouring to prevent over-
collecting owing to nature study, or by the public
in general. Fifty thousand leaflets were issued
alone to the schools. The object of the Section is
to create a public opinion in favour of a better treat-
ment of wild flowers. None will gainsay the need
of this.
It is further desired to achieve certain definite
means of protecting plants or obtaining reservations
by the help of county councils, rural district councils,
landowners, and scientific societies. The last have
recently been appealed to, and a fair measure of
success has apparently been obtained ; but it is
desirable that all societies should support so worthy
an object by the appointment of a corresponding
secretary to assist the Section in its work. In a
short notice of so important a matter as this it is
impossible to state, more than briefly, the ideals of
those who have set themselves the uphill task of
obtaining what in Prussia is known as State protec-
tion. To the few, probably, this would be distaste-
ful, as implying more officials and the intrusion of
bureaucratic methods in scientific affairs ; but without
the machinery of the State, in the absence of an active
and generous public support, there is apparently no
present medium for enforcing what is certainly the
public opinion in this matter — that is, a determination
to prohibit premeditated vandalism, or, what is as
bad, careless extermination from want of foresight
or knowledge.
The general adoption by all county councils of
the principle of obtaining a local order for prohibit-
ing hawking on public highways would, we think,
come to much the same thing as a Wild Flowers
Protection Act, if, in addition, private lands could by
a consensus of assent on the part of all the great
landowners be protected by the framing of rules
relating to private property.
In the meantime the work of this Section, which
Mr. Horwood describes, should have the support of
all who feel strongly about this matter. They can,
moreover, we may be permitted to say, by obtaining
copies of the leaflets cited, do much good in their
own districts in their own way by distributing them
and remonstrating on every possible occasion with
those who are guilty of vandalism. And there is
no doubt that any suggestions of a useful nature,
or actual cases of extinction or diminution coming
within the individual experience of readers of
" Knowledge," that may be sent to him will be
welcomed by the author of these cogent appeals
as additional evidence in support of this movement
for the public good.
:t " The Protection of Wild Plants" (Selborne Society, Special Leaflet No. 1); "An Appeal to Nature Study Teachers"
(Ibid., Special Leaflet No. 2) ; " To the Public " (Ibid., Special Leaflet No. 3) ; " The Need for State Protection of
Wild Plants," Westminster Gazette, March, 1913; "The State Protection of Wild Plants," Science Progress, April,
1913; "The Preservation of our Wild Plants," School Nature Study, June, 1913. A. R. Horwood (Leicester
Museum), Recorder, Plant Protection Section, Selborne Society.
t These can be obtained from the Secretary, 42, Bloomsbury Square, London, W.C.
CORRESPONDENCE.
THE PATH OF VESTA.
To the Editors of " Knowledge."
Sirs, — Professor Pickering, in an address to the British
Astronomical Association, suggested last month that it would
be an interesting and useful work for amateurs to trace the
path of Vesta in the sky, and to compare its magnitude with those
of adjacent stars ; so we have made and verified a small map
(see Figure 355) with the path of the little planet for alternate
days in August, with all adjacent stars down to 7-5 magnitude.
The designation of star by number and zone is from the Harvard
Durchmusterung, and the magnitude of each is given in Tabic
317
318
KNOWLEDGE.
August, 1913.
57. For any amateur who has a good binocular glass, it may
prove useful. The magnitude of Vesta on August 4th,
according to Dr. Crommelin, is 6-1.
FIAMMETTA WILSON,
S. A. WILSON,
Members of the British Astronomical Association ;
Metnbres de la Societe Astronomique
d'Anvers.
Bexley Heath.
Table 57.
4
xxi 56
5*
48 44
4"
36
'9
it
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If
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20
;(,
IS
»
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_
22
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V
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V
b
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7
-
=4
it
rf
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%
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25
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I x*l 5° 5* 48 44 40 36
XX
Figure 345.
Map of the Path of Vesta showing neighbouring Stars in
Capricornis.
Star magnitudes and star numbers from Harvard Durch-
musterung.
Abbreviations. — Fl. = Flamsteed. Number followed by
G = number from Manometria Argentina.
Star Number or
Epoch
1900.
No.
on Map.
Star Name in
Harvard Durch-
Mag.
musterung.
R.A.
Dec.
Hr. Min. Sec.
.
.
1
-22. 5511
7
■5
20 37 36
-22
49
2
- 26. 15227
8
•0
20 37 52
-26
11
3
- 19. 5905
7
3
38 12
19
42
45 G
6
7
39 12
27
37
f Capricorni
4
3
40 12
25
38
Flamsteed
17 Capricorni
5
9
40 24
21
53
4
- 24. 16262
7
2
40 24
24
6
5
- 27. 15025
7
0
40 30
27
14
6
- 22. 5526
8
0
40 42
22
32
7
- 19. 5921
7
0
40 52
19
48
8
- 26. 15264
7
3
41 24
26
47
9
- 23. 16498
7
5
42 0
23
51
10
- 19. 5928
6
5
42 30
19
38
11
- 23. 16508
7
4
42 36
23
7
52 G
6
1
43 24
26
9
12
-27. 15065
7
3
44 6
27
45
13
- 25. 15067
6
9
44 36
25
21
14
- 21. 5844
6
8
45 6
21
40
15
- 27. 15080
6
8
45 36
27
37
w Capricorni
4
1
45 52
27
18
16
- 20. 6055
7
0
46 30
20
1
17
-21. 5852
7
3
46 36
21
36
18
- 19. 5942
8
3
46 42
19
7
58 G
6
6
47 12
24
9
59 G
6
5
47 48
19
29
19
- 24. 16339
7
3
48 12
24
39
59a G
7
3
48 24
19
22
20
- 26. 15326
7
5
48 30
25
57
21
- 21. 5864
7
5
49 0
21
20
22
- 19. 5960
7
0
49 6
19
10
63 G
6
1
50 52
26
41
23
- 22. 5572
7
5
51 6
22
23
20 Flamsteed
6
2
53 52
19
26
Capricorni
67 G
6
2
55 52
27
17
24
- 19. 5998
7
0
57 6
19
39
25
-25. 15195
7
3
57 30
25
28
26
- 24. 16443
7
4
58 0
24
43
27
- 27. 15222
8
1
58 36
27
8
v Capricorni
5
0
58 42
20
15
28
- 20. 6127
6
8
21 1 0
20
35
29
- 23. 16698
7
4
1 6
23
37
30
-23. 16700
7
0
1 18
23
33
A Capricorni
4
8
1 18
25
24
31
- 27. 15255
7
3
1 30
27
41
32
- 19. 6024
7
0
1 48
19
29
33
- 22. 5612
7
8
2 6
22
44
X Capricorni
5
3
21 2 48
-21
36
34
- 27. 15275
7
5
21 3 12
-27
31
35
- 24. 16495
7
4
3 24
24
2
36
- 20. 6140
7
0
3 30
20
36
78 G
6-5
21 3 52
-20
57
REVIEWS.
ARCHAEOLOGY.
Church Bells of England. — By H. B. Walters, M.A.
F.S.A. 400 pages. 170 illustrations. 9-in.X6-in.
(The Oxford University Press. Price 7/6 net.)
This book taken generally is exceedingly well written, the
illustrations, one hundred and seventy in number, are good,
especially the one on page 11 showing a man playing on an
octave of bells ; see also page 31, whereon is shown a finished
bell and method of casting. Other illustrations of the "copes,"
" cores," and moulds joined are interesting (pages 37, 39, 41),
and of the completed peal on page 43. The twelve ringers at St.
Paul's Cathedral (page 75) forms a good picture, and furnishes
an excellent idea of what the ringing chamber there is like.
Copies of old prints appear on pages 258, 259, and 260, and
these show the " washing," " blessing," and " censing " of a
August, 1913.
KNOWLEDGE.
319
bell in bygone days, whilst the chapter (XIII) on the decoration
of the castings is particularly interesting. It is pleasing to
note that the writer agrees with Canon Simpson's principle of
tuning bells, and he rightly observes that it is a mistake to
retain " maiden " bells in a peal when they would be the
better for tuning.
In a complex work of this description there is bound to be
a few " slips " which may be well to correct in a future
edition. For instance, on page XIII the date of the " Clavis "
is given as 1888; it should be 1788. The stating of the
changes on page 83 is incorrect, and the same error occurs on
page 84. It may be a printer's error on page 83 where the
word " courses " is given instead of " changes," but the
writer on page 141 calls "touches" ''peals." A " peal " is
the extent of changes obtainable, whilst a " touch " may be a
number less than the extent.
It is stated that the second bell at Aldbourne, Wilts, was
given "by anonymous donors" (page 340), but such is not the
case, for the names of the donors are plainly cast upon the
bell, and the full inscription is as follows : — ■
" The gift of Jos: Pizzie and Wm. Gwynn of Aldbourn. .
Robert Wells fecit 1787.
Music and ringing we like so well,
And for that reason we gave this bell."
W. L.
CHEMISTRY.
The Interpretation of Radium. Being the Substance of
six free popular experimental Lectures delivered at the
University of Glasgow. — By Frederick Soddy, M.A.,
F.R.S. 3rd Edition, revised and enlarged. 284 pages.
33 illustrations. 8j-in. X 5£-in.
(John Murray. Price 6/- net.)
In the third edition of this work, whilst the original lecture
form has been retained, many additions have been made
concerning recent investigations, including a new final
chapter dealing with the thorium and actinium series of
radioactive elements. Controversial matters have been
avoided as far as possible, but Mr. Soddy does something
less than justice to the electronic theory of matter (with all its
faults) when he dismisses it as based upon extravagant
assumptions (page 151). Concerning transmutation Mr.
Soddy shows that the study of radioactivity indicates the •
possibility of achieving this ; but he asserts that transmutation
has not yet been accomplished, entirely ignoring the experi-
mental work of Sir William Ramsay on the subject, which
certainly ought to have been mentioned, even if regarded as
inconclusive. Another matter that calls for criticism, is that
Mr. Soddy does not clearly distinguish between the aim of
science (namely, the correlation of phenomena) and that of
metaphysics, which is concerned with the source or cause of
phenomena. Thus, he uses " matter " as a metaphysical
concept, defining " mass " as " quantity of matter " (an
exceedingly vague metaphysical expression), whilst at the
same time stating that " mass " is measured by " inertia."
Energy, moreover, is spoken of in the book as though it were
a metaphysical entity.
Apart from these faults, however, it must be freely admitted
that there is much that is excellent in the book — as, indeed,
one could only expect from a man to whom the science of
radioactivity owes so much. Apart from the tendency to
untenable metaphysics, already indicated, the style is clear
and precise, and the language is simple and adapted to the
needs of the ordinary reader, who requires a general account
of the new science, in which technicalities and matters of
detail are avoided as much as possible.
In one chapter, which is frankly speculative, but by no
means the least attractive in the book, there are some very
interesting speculations arising out of the consideration of the
geological significance of radioactivity and the evolution of the
elements. Mr. Soddy suggests that there may have been, in
the dim distance of the past, a civilisation on this earth in
advance of the present, to whom the secrets of the elements
were known, and that the traditional theories of the
mediaeval and older alchemical philosophers (which in certain
cases, as Mr. Soddy points out, seem to express at times, in
allegorical form the views of modern science) were the
remnant of heritage from this past.
H. S. Redgrove.
GEOLOGY.
The Earth : its Genesis and Evolution. — By A. T. Swaine.
277 pages. 64 illustrations. 8j-in.X5-in.
(C. Griffin & Co. Price 7/6 net.)
Although this work is confessedly a compilation, it may be
commended to general readers and lower-grade students as a
well-written and, on the whole, trustworthy exposition of the
leading factors in the evolutionary history of the earth, with
passing notices of the faunas of the different epochs.
Scientific terms are avoided so far as possible ; but the
author in a very large number of instances has given
references to authenticate particular statements, so that the
student desirous of entering more deeply into the subject
will have no difficulty in finding where to turn for further
information.
Commencing with the consideration of the various theories
of planetary genesis and the beginning of the earth, the
author, after a chapter on the leading physical features of the
latter and its movements in space, gives an excellent survey of
the igneous and sedimentary rocks and their mutual relation-
ship and sequence. Very wisely, he has omitted all reference
to guesses as to the supposed age of the globe in years,
remarking that these have practically no basis of fact, and
also that figures of such magnitude are beyond the scope of
the ordinary human understanding. The fact that nearly all
the great mountain chains of the old world are of Tertiary
age is brought very prominently before the reader ; but it
might have been added that the stupendous physical changes
involved in such movements serve to demonstrate that
compensating changes must have occurred in other parts of
the world, and consequently that the arguments of those who
urge the stability of continents and ocean-basins are of little
value. Perhaps the least satisfactory parts of the work are
those dealing with extinct vertebrates, with which the author
seems to have but a very slight acquaintance. It is, for
instance, incorrect to describe the figure of the skeleton of
Diplodocus (page 168) as that of a restoration of the animal;
while the statement (page 171) that the terrestrial dinosaur
Brontosaurus was not unlike an Ichthyosaurus or a
Plesiosaurus in form will astonish every palaeontologist. It
must, too, have been a remarkably big Newfoundland dog
that rivalled the ancestral elephant Moeritherium (or
Moerithrium, as it is misspelt on page 196) in size. These,
however, are blunders which detract but slightly from the
value of an eminently readable book. R ,
PHYSICS.
Wireless Telegraphy. — By C. L. Fortescue, M.A.
143 pages. 20 illustrations. 6f -in. X 5-in.
(The Cambridge University Press. Price 1/-.)
The series to which this little book belongs has already
become widely known, and may fairly claim that it supplies
" simple, concise, and reliable information." On such a
subject as Wireless Telegraphy this combination of qualities
is not easy of attainment. The author has succeeded in
putting within the compass of 143 pages the main principles
of current induction, condensers, oscillatory currents,
resonance, and electromagnetic waves, along with details of
the various processes of transmitting and receiving, followed
by chapters on wireless telephony and on the history of the
development of the whole subject. At a first glance the
statements seem to be well and clearly put, and a reader who
knows something of electricity in practice will doubtless find
much help from a book of this kind. It is doubtful whether
any book can supply such help to those who have no practical
acquaintance with electricity. These, however, are becoming
fewer in number. On page 132 we observe that Hertz is said
to have published the results of his experiments with oscil-
320
KNOWLEDGE.
August, 1913.
lating currents in the year 1878. Surely two figures have
become transposed, for Clerk Maxwell died in 1879. It is,
perhaps, unfortunate that three pages are devoted to the
Marconi Agreement of 1912.
VV. D. E.
ZOOLOGY.
Text Book of Zoology.— By H. G. Wells, B.Sc. and A. M.
Davies, D.Sc. 487 pages. 207 figures. 7-in. X 5-in.
(The University Tutorial Press. Price 6/6.)
Mr. H. G. Wells, when he was a teacher of Zoology, planned
out this book, which was rewritten by Dr. Davies. Now the
sixth edition has been carefully revised by Mr. J. T. Cunning-
ham, who has added a summary of the modern ideas with
regard to evolution, which we have read with very great
interest.
W. M. W.
Wild Life in Wales. — By George Bolam. 405 pages.
62 illustrations. 9-in. X 6-in.
(Frank Palmer. Price 10/6 net.)
There is a wealth of interesting information in this book
which deals first of all with sheep-dogs and agriculture, but as
its name implies is mostly occupied with first-hand observa-
tions on the wild life of Wales. There are also included
some very useful discussions as, for instance, the one with
regard to the development of spots on birds' eggs. For the
mole it is claimed that the damage he may do is so insignifi-
cant that it may be ignored, " while his hillocks form a good
top dressing to the grass and are gradually spread by sheep,
who thereby, it has been claimed, help to grind off the
superfluous growth with their own hoofs." It is pleasant to
learn some good also of the carrion crows, which Mr. Bolam
says for the greater part of the year are nearly as assidious as
rooks in hunting and destroying beetles, wireworms and so
on. The lover of nature will be delighted to hear of the
chough, the buzzard, the peregrine falcon, the polecat and the
marten, and also to see many of the excellent photographs
which have been used as illustrations, while here and there
those to whom antiquities have a charm will be glad to find
details of the hand-plough, the flail and the rushlight.
W. M. W.
"/•" A Memoir of John Willis Clark, Registrary of the
University of Cambridge and sometime Fellow of Trinity
College.— By A. E. Shipley, F.R.S. 362 pages. With
3 portraits. 8£-in. X 5j-in.
(Smith, Elder & Co. Price 10/6 net.)
To almost every Cambridge man who matriculated between
the middle sixties and the earlier years of the present century
the name of J. W. Clark — abbreviated at first to "J. W. " and
then to " J " — must have been more or less familiar. For its
owner occupied a unique and prominent position at the
University, while his many-sided activities brought him into
contact with undergraduates of diverse types, from serious
zoological students to the light-hearted members of the
Amateur Dramatic Club. And as every alumnus who
came in contact with Clark could not fail to be attracted by
his genial, if somewhat cynical, disposition, they should all
rejoice that the book escaped the dire fate of being privately
published.
To the naturalist the chief interest of the book is concentrated
in the appendix on Clark's long career (from 1866 till 1891)
as Secretary and Superintendent of the University Zoological
Museum ; an institution which may be said to have attained
its present high status as a teaching unit as the result of the
energy and hard work of its Superintendent, combined, it
should be added, with the assistance of the then Professor of
Zoology, the late Alfred Newton. But Clark succeeded in
making the museum under his charge a great deal more than
a teaching centre by obtaining for it many collections of high
scientific value to which students will constantly resort so
long as they remain in existence. Of actual scientific work
Clark did comparatively little, partly, no doubt, through lack
of the proper training in early years and partly owing to the
pressure of his administrative duties. In the early part of his
career as Superintendent he published, however, some papers
on sea-lions, which were of considerable value in clearing up
the confusion then existing with regard to the number of
species and their distinctive characters.
No one better suited to the task of writing the life of his
old friend could possibly have been found than Dr. Shipley,
to whom all contemporary Cambridge men owe a debt of
gratitude. j^ ^
NOTICES.
BIO-ECONOMICS.— Dr. Reinheimer is about to issue,
through Messrs. Kegan Paul, Trench, Triibner & Company,
a contribution to evolutionary science in the form of a
volume entitled " Evolution by Co-operation — A Study in Bio-
Economics."
FOREIGN BOOKS.— Messrs. W. & G. Foyle have opened
at 5, Manette Street, W.C., a Foreign Book Department
containing, we are told, volumes in every language and on
every conceivable subject, carefully arranged and classified.
SCIENCE FOR ARTISANS.— To meet the want of highly
intelligent artisuns for something more concrete than theory,
Messrs. Constable & Company are bringing out a series of
short, simply-written monographs by competent authorities
under the title of " Thresholds of Science." The books will
be well illustrated, and the volumes on Zoology, Botany,
Chemistry and Mathematics are now ready.
HISTORICAL MEDICAL MUSEUM.— This Museum,
which has been set up at 54a, Wigmore Street, is formally
recognised as part of the History of Medicine Section of
the International Medical Congress which is now being held
in this country. The collections are due to the munificence
of Mr. Henry S. Wellcome, and to the most interesting speci-
mens and models brought together by his and his assistants'
labours we hope to devote a special article in the near future.
SECOND-HAND BOOKS. — Mr. Edward Baker, of
Birmingham, has sent us his catalogue of Second-hand
Books, numbered 319, and among the thirteen hundred items
described in it we notice many having reference to various
branches of science, while there are special headings dealing
with Botany, Ornithology, and General Zoology.
NEW EDITIONS.— Messrs. J. & A. Churchill, of 7, Great
Marlborough Street, W., have nearly ready for publication
the 7th edition of " The Microtomist's Vade-Mecum," by Mr.
Arthur Bolles Lee; the 6th edition of the late Professor J.
Campbell Brown's " Practical Chemistry," edited by Dr.
Bengough ; and the 3rd edition of " A Text- Book of Physics,"
edited by A. Wilmer Duff.
JOURNAL OF CHEMICAL TECHNOLOGY.— The
Publications Committee of the Association of Chemical
Technologists announce that in future the " Journal of
Chemical Technology," the official organ of the association,
will be published quarterly, and that the July number will
be the first of the new issue.
BAUSCH & LOMB MICROSCOPES.— We have received
the Bausch & Lomb Optical Company's catalogue of micro-
scopes which contains particulars of two new stands " F "
and " FF " the latter of which has a focussing sub-stage.
A special feature of these microscopes is the base, which is
of a modified horse-shoe form of rounded contour. These
models, which embody all up-to-date bacteriological require-
ments have been introduced to meet the popular demand
for a high-class instrument at a moderate figure. Incident-
ally we may mention that the Bausch & Lomb Optical
Company have now sold more than eighty-seven thousand
of their microscopes.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
SEPTEMBER, 1913.
THE EXISTENCE OF LUMINOUS BIRDS/
By COUNT L. de SIBOUR.
Few students delve deeply in natural history with-
out encountering the topic of luminous birds, and
the pros and cons of the subject are developed by
the reader with a frequency that tests the credulity
of any superficial investigator. That birds having
the quality of luminosity have long existed seems a
fact beyond dispute. Especially true is this in
England. In 1907 Sir Digby Piggott called the
attention of ornithologists to the appearance of
luminous birds in Cambridge, and these unusual
members of the feathered family had already been
noticed by others in the same county, and especially
by Mr. J. H. Gurney, of Norwich, who spread the
news on the Continent through the French
ornithologist, M. Ternier, in The Ornithological
Review of France.
It seems that as early as 1866, in the same county,
Mr. J. A. Harvie-Brown had mentioned "moving
lights " frequently seen at night. But no special
attention had been paid to these reports, as they
were believed to have originated in the credulous
minds of country folk.
The more frequent apparitions in 1907 at last
aroused the attention of naturalists, especially in
France, where similar cases had been observed in
the Vosges and in the Pyrenees.
According to Sir Digby Piggott, a couple of
luminous birds were seen near Twiford, Norfolk,
in February, 1907, by a gamekeeper, who, having
killed one, identified it as a common barn owl (Strix
Hammed). In October, 1907, Mr. B. J. Purdy and
Mr. Spencer saw another which was seen again on
the 19th and 22nd of December. On the first
occasion it seemed to have attained the maximum
of luminosity, as the branches of the tree upon which
it had perched were visible in the pale yellow glow.
This light did not frighten the mice ; for the bird
was seen to drop upon them several times.
The power of the light was that of a bicycle lamp
seen three or four hundred yards off, and its strength
diminished considerably when the bird's flight was
in a direction away from the observer. This pointed
to the inference that the luminosity was confined to
the breast.
According to Mr. C. L. Harman, a luminous bird
was seen by him in the marshes of Haddiscoe, on the
25th day of December, 1907. Similar apparitions
were recorded during the years 1907 and 1908 ; but
in 1909 they ceased, and none has since been
observed.
The glow on the breast of the barn owl is un-
doubtedly due to phosphorescence, and the moulting
of the feathers explains its sudden extinction.
Two theories were given as to the origin of this
unusual luminosity.
Mr. Gurney, who had the opportunity of observing
several specimens of these birds, thought it probable
that the owls had been in contact with phosphores-
cent wood, and that phosphorescent bacteria
had attached themselves to the feathers. This
opinion at first was generally accepted, especially
in Norfolk, where many birds had been seen,
and was apparently confirmed when Lord Lindley
announced that on his property there was a
"Extracted from Articles by L. Ternier, in The Ornithological Review of France.
321
322
KNOWLEDGE.
September, 1913.
beech tree showing a patch of phosphorescence
eight inches square. It was therefore surmised
that the birds had inhabited holes infested by
this bacterium. The other theory was that dampness
and uncleanliness of the covering of the breast had
favoured a sudden growth of luminous fungi peculiar
to feathers. This explanation appears to have been
more plausible ; for in the contact theory it would
seem that the wings and head, rather than the
breast, would be likely to touch the sides of the
hole. Yet these parts produced little or no light.
Again, it would necessitate the bird being a tree-hole
dweller, whereas similar cases have been observed
on Canadian blue herons, for which this kind of
life is impossible.
The phenomenon is not confined strictly to wild
birds. Cases are also found among domestic pigeons.
The locating of the light on the breast can be ex-
plained by the fact that the feathers are finer and
thicker on that part of the body than on any other,
except the neck. It is also a part that the bird can-
not thoroughly clean, and will therefore retain the
greater part of the germs and dust gathered in flight.
The peculiar increase of light during flight is prob-
ably due to a chemical action of the air producing
superoxygenation, as it is well known that the agita-
tion of a medium containing phosphorescent particles
intensifies the luminosity of the latter.
The balance of argument is thus in favour of the
fungi theory, and the latest observations of Senor
Elorza in Spain are a confirmation of it. On
several nights he saw a couple of luminous birds.
Upon inquiry he was informed that they had been
noticed for several years, that they lived in cliffs
near by, and that they disappeared in the month of
May. The description given by him did not answer
to that of the Barn Owl, and it is to be supposed
that we are in presence of another bird, one of
nocturnal habits, offering a similar case of phos-
phorescence. These specimens did not live in trees,
but in cliff-holes. Their disappearance in May is
accounted for, as in the other cases, by the spring
moulting of the feathers.
It might be of interest to look back to the works
of the earlier naturalists and note that several
observers were aware of the existence of luminous
birds. The first to record their appearance was
Pliny. He mentions them in his account of the
Hercynian forest (" Historia Mundi," X, 47). Two
hundred years later Solin, in the twentieth chapter
of his " Polyhistoria," alludes in much the same
way to what the great Latin naturalist had observed :
" Soltus Hercynius aves gignit, quarum pinnae per
obscurum emicant et interlucent, quamvis densa nox
denset tenebras." It is probable that he was not
unacquainted with Pliny's works.
The first work solely devoted to luminous animals
was written in 1555 by Conrad Gessner : " De
raribus et admirandis herbis, quae sive quod noctu
luceant,sive quod alias ob causas lunariae nominantur,
et obiter de aliis etiam rebus, quae in tenebris lucent."
He speaks of plants and grass shining at night, and
seems to have an obscure idea of the origin of this
phenomenon, which he calls " res naturae luscentes."
Finally, in 1647, Thomas Bartholin published his
great work, " De luce animalium." This is a com-
pilation, in three volumes, of observed (and some
problematical) cases of luminous animals. The third
book is entirely devoted to birds, and in it are
mentioned the Phoenix, the birds of Diomedes, the
" Incendiaria avis," which set on fire any tree or
house on which it perched ; the cock " cum luce
consensum alit," whose feathers had robbed from
the sun their brilliant metallic shine.
But among these quaint beliefs one finds observa-
tions very probably true. In 1641, at Montpellier,
in France, during a short period of famine, many
fowls were brought to market. Several of these
birds attracted wide attention by their unmistakable
phosphorescence, and Henri de Bourbon, Prince de
Conde, was called to admire them. A cock was
killed "who shone on all parts of his body with a
remarkably strong light," " veram totius corporis
lucem . . . aperte exserint." The same year, at
Montebello, according to the author, there was a
hen which " shone like a ball of white fire." And
Thomas Bartholin, comparing these two birds,
ingeniously adds : " It is a pity that the cock did
not meet the hen ; for we might then have obtained
a breed of incandescent fowls."
A SIMPLE METHOD OF DIFFERENTIATION BETWEEN MALTOSE
AND LACTOSE IN THE SOLID STATE. .
A solid is given which reduces Fehling's Solution and does
not reduce Barfoed's Solution. The solid must be either
Lactose or Maltose.
(1) Take some of the solid and place it in a clean dry test
tube.
(2) Add from 5 c.c. to 10 c.c. of absolute alcohol and shake
well.
[The alcohol should not be heated as Lactose is sparingly
soluble in warm alcohol and might give an erronous result, j
(3) Then filter through a clean, dry filter funnel and receive
the filtrate into an evaporating dish.
(4) Evaporate the filtrate on a water-bath nearly to dryness,
(5) To the filtrate then add a few c.c.'s of diluted Fehling's
Solution and warm.
[Before adding the Fehling's Solution a sample should be
tested to see that it does not reduce of its own
account.]
(6) If reduction takes place, Maltose is present ; if no
reduction, Lactose.
This differentiation can be carried out within the space of a
few minutes with quite a small amount of solid and with very
little apparatus. It is very useful when sugar is mixed with
a protein which will prevent one from obtaining an osazone
or a polariscope reading.
The London Hospital,
VICTOR FELDMAN,
THE ZODIACAL LIGHT.
By the Late F. W. HENKEL, B.A., F.R.A.S.
Astronomers are generally agreed to consider
this phenomenon as falling within the purview of
their science, though there have not been wanting
some who, by a wide extension of the term
Meteorology — t« /ueTeupa," things aloft" — have rather
included it under the latter heading. Inhabitants of
towns, " those in populous cities pent," are not
often favoured with a view of its delicate luminosity,
the multitude of artificial illuminations completely
veiling its feebler intensity. But in tropical regions
it is a fairly regular phenomenon and, according to
Humboldt and other observers, its brilliancy often
greatly surpasses that of the Milky Way.
In our latitudes, the Zodiacal Light is best seen in
the evenings of February and March, being then
nearly perpendicular to the western horizon ; in the
autumn mornings it is to be similarly seen in the
east before sunrise. As seen on a late February
evening it has the appearance of a cone or lens-
shaped beam of light reaching from the horizon
towards the zenith, following generally the course of
the ecliptic (or perhaps that of the Sun's equator),
whence its name, the Zodiac being that part of the
sky within which are performed the apparent move-
ments of the Sun, Moon, and the principal planets.
This cone has its base at the horizon, and its vertex
is at a distance from the Sun's position varying from
50° to 90°, the breadth of the base being not less
than 8° or more than 30°. Cassini and Mairan
observed it, at times, not less than 100° from the
Sun's place, and occasionally even further, showing
its extension in space beyond the Earth's orbit.
Humboldt and Brorsen seem to have been
amongst the first to observe a second light in the
East at the same time that there was a principal
light in the West, a narrow band of fainter
luminosity uniting the two, whilst Flammarion says
that in the equatorial regions of the Earth the
conical form disappears with the last trace of twilight,
and by " night there is seen a luminous band forming
a more or less complete circle in the sky, sometimes
stretching from West to East, the parts nearest the
Sun being the most brilliant, other regions less so,
the whole of a pure white tint." In the region of
the sky exactly opposite the Sun's place there is
often seen a patch of several degrees diameter, more
luminous than the surrounding portion, and this is
known as the " Gegenschein," or counterglow.
Whilst under the Tropics the light is of pure white
colour, in our latitudes it is more commonly of a
reddish tint, especially at its base ; this is, however,
probably due to the last traces of twilight.
Humboldt, however, says ("Cosmos," Vol.1): " I have
occasionally perceived not exactly a reddish colora-
tion, nor the lower part darkened, nor even a
scintillation such as Mairan asserts he has seen, but
a sort of tremulous shivering of the light."
It is perhaps a little surprising that the zodiacal
light seems to have escaped the notice of the ancient
astronomers, unless we may suppose that a reference
to the " trabes " by Pliny, in his " Natural History,"
may be so interpreted ; but this is more probably an
allusion to the aurora. Kepler and Descartes make
obscure allusions which may be interpreted to
indicate their familiarity with it ; but the earliest
authentic mention of the light occurs in the works
of Childrey, Chaplain to Lord Henry Somerset,
who, in his " Natural History of England " (1659)
and his " Britannia Baconica " (1661), was the first
to draw the attention of his contemporaries to the
remarkable observations made by him during several
previous years, in the evenings of February and
March, after sunset. About twenty years later,
Dominique Cassini gave considerable attention to
the phenomena as seen in Central Europe, and
studied them " in all their bearings with regard to
space," formulating a theory of their origin which
differs but little from that generally admitted by
present-day astronomers. He considered that the
light was produced by a ring of small planetary
bodies revolving in orbits nearly in the plane of the
Ecliptic and reflecting the light of the Sun. He
even thought that the fall of meteoric stones or
bolides might be due to the passage of our Earth
through this ring. The principal difference between
this and later views consists in regarding the in-
numerable small particles as rather forming a thin,
flat sheet partly lying between the Earth's orbit and
the Sun and partly beyond it, the light being due to
reflection mainly, but perhaps, as we shall see later,
to a small extent intrinsic also. It is by no means
impossible that to the action of the denser part of this
layer of "meteoric dust " within the orbit of Mercury
may be due the unexplained motion of the peri-
helion of that planet's orbit as detected by Leverrier.
Sir John Herschel says : " It may be conjectured
to be no other than the denser part of that medium
which, as we have reason to believe, resists the
motion of comets, loaded, perhaps, with the actual
materials of the tails of millions of those bodies of
which they have been stripped in their successive
perihelion passages."
Liais and Mayer thought that to this layer might
be referred the maintenance of the Sun's light and
heat, " the meteoric theory of solar radiant energy."
Materials must be continually falling upon the Sun's
surface, and the "arrested motion" transformed into
heat, thus making up for that lost by radiation, so
323
324
KNOWLEDGE.
September, 1913.
that the Sun might long continue in this way to heat
and illuminate the planets. But the insufficiency of
this process is a fatal objection, except as possibly
affording a minute portion of the solar radiation ;
for, were the Sun's heat thus maintained at its pre-
sent rate of emission, calculation shows that our own
Earth and the nearer planets would be subject to a
bombardment also, sufficient to add about fifty tons
of meteoric matter on each square mile of the Earth's
surface per day ; whereas in reality the actual amount
falling is not one-millionth of that quantity. The
fall of sufficient material in such vast quantity
implies the presence of a yet greater amount in the
surrounding regions, and very evident effects upon
the motions of the planets would also be perceived
which are not observed. Nevertheless, the idea that
a balance between expenditure and receipts is kept
up in this way seems so beautiful an one that we may
perhaps be permitted to regret that it is not true.
Long-continued observations of the light were
made by the Rev. G. Jones, chaplain of the
American steamship " Mississippi," during a cruise
of two years round the world, and his observations
and results were published in a beautiful volume
during the year 1858. The final conclusion at
which he arrived from the totality of his observa-
tions was that the zodiacal light is produced by a
nebulous ring having for its centre the Earth, which
lies within the orbit of the Moon ; in other words,
a kind of terrestrial ring like one of the rings of
Saturn. Captain Wilkes, a well-known American
navigator, objected to Jones's views and proposed an
alternative theory that the zodiacal light is simply a
terrestrial meteorological phenomenon, the result of
the illumination of that part of the Earth's atmo-
sphere upon which the sun falls vertically within
the tropics. The Dutch observer Gronemann
similarly considered the light to be of terrestrial
origin, and denied that the relation asserted to exist
between the luminous cones seen in the east in
the morning and those seen in the west during the
evening had been established ; he also declared that
it had not even been proved that they shared the
apparent diurnal motion of the heavenly bodies. In
1876 Serpieri, of Urbino, presented to the Italian
Spectroscopic Society a memoir dealing with the
results obtained by various previous observers, and
gave as his opinion that the light was of electrical
origin, perhaps analogous to the aurora. Thus we
see that there is still much to be done before we can
be said satisfactorily to understand this mysterious
phenomenon, although, as we shall point out later
on, there are good reasons for thinking that the
" auroral " theory of the zodiacal light arises from a
confusion of ideas.
Long ago Humboldt, whose interest had been
excited by finding the intensity of the light much
greater in Spain than in Germany, expressed his
astonishment at the variability of this phenomenon
under the tropical skies of South America. Even
whilst its luminosity was greatest it would for some
minutes diminish appreciably, and then without
warning brighten up again to its former intensity.
"The strength of the light increased in a remarkable
manner as I approached the Equator in Southern
America. In the constantly clear and dry atmo-
sphere of Cumana, in the grassy llanos of Caracas,
on the elevated plains of Quito, and in the Gulf of
Mexico, especially on the plateaux (of ten thousand
to twelve thousand feet above sea level), where I
stayed for some time, I noticed that its brilliancy
often surpassed that of the brightest part of the
Milky Way between Argus and Sagittarius, or,
speaking of the part more familiar to us in the
northern hemisphere, that part between Aquila
and Cygnus " (" Cosmos," Vol. IV). On the whole,
however, Humboldt considered that the brilliancy
of the zodiacal light did not increase with the
altitude of the region where it was observed. He
insisted especially upon " the intrinsic variability
of the phenomenon itself," but he did not dispute
the possibility of the influence of varying atmo-
spheric conditions, the greater or less transparency
of the upper and lower strata of the air upon its
brightness, as we have already noticed with regard
to the coloration perceived in extra-tropical regions,
scintillation, and so on.
Amongst others who have studied the various
phenomena, Professor Searle has also devoted much
time and thought to the different theories pro-
posed. Dealing with the observations of Jones and
others he concludes that the zodiacal light varies
in position during the course of the year, being
more to the north in autumn than in spring (of our
hemisphere) ; atmospheric absorption has a great
influence also upon its apparent position ; the zone
of the sky occupied by the minor planets presents
peculiarities like those of the zone occupied by the
light, and thus one is led to think that the latter
also is due, in part at least, to small bodies moving in
planetary orbits. The light does not interfere with
the visibility of even faint stars, and it disappears
by setting, and not by growing fainter. This last
movement, due to the Earth's diurnal motion, as we
have seen, was denied by Gronemann.
From observations made at sea whilst in the
Tropics during 1862 Helis concluded that the
change of position of the light depends more on the
time of year than on the situation of the observer.
Colonel Tupman made a number of observations
from 1869 to 1871 in Southern Europe, and gave an
account of his work in The Monthly Notices of the
Royal Astronomical Society, Vol. XXXII. He stated
that the axis of symmetry of the light with regard
to the Ecliptic varied considerably during the course
of the year, being almost parallel to that plane in
winter and making an angle of as much as 20°
with it in August and September. He also
asserted that the plane of the light did not pass
through the Sun. If this be indeed the case it would
seem that the matter composing it does not turn
round the Sun, but his observations differ very
September, 1913.
KNOWLEDGE.
325
considerably from those of others. About the
same time the late A. C. Ranyard, formerly editor of
" Knowledge," was in Sicily for the purpose of
observing the famous total eclipse of the Sun in 1870.
He examined the luminosity of the zodiacal light
with the Savart polariscope, and saw that this gave
distinct signs of polarisation, thus concluding that
the material giving rise to it is either composed
of particles so small that their diameters are com-
parable with the wave-length of light, or else is
composed of matter capable of giving " specular
reflection." Angstrom, of Upsala, the famous
spectroscopist, concluded from his observations that
the substance emitting this light is the same as that
which causes the aurora. He thought that he saw
the " brilliant auroral line " (5567) in its spectrum ;
but as the aurora is a phenomenon of far greater
frequency in Sweden than in regions further south,
his observations, through the possible confusion
between two coexistent phenomena, are subject to
considerable uncertainty.
Acrimiz, at Cadiz, also observed a faint continuous
spectrum with two brilliant lines, one yellow
{"probably an auroral line") and another bright
line in the blue, more refrangible than the F line of
hydrogen, which he thought was identical with
another auroral line, but which he could not identify
with certainty. " As," says Professor Michie Smith,
" his observations were made with an instrument
whose dispersion was much too great to allow of the
visibility of the faint luminosity of the zodiacal
light," it seems fairly certain that this was not the
phenomenon which he had observed at all.
Important observations have been made by
Barnard in America, Max Wolf at Heidelberg, Innes
at Johannesberg, Ferrari, Maxwell Hall, Backhouse,
and others ; but to enable us to arrive at a completely
satisfactory theory it is evident that we must have
more observations made in elevated regions, where
the influence of the denser part of the atmosphere
and other disturbing causes have less influence, as
well as careful measurements made over a term of
years. Hitherto we have had to rely mainly upon
observations made too near the sea level, under
unfavourable conditions, and of a spasmodic nature.
Thus it can scarcely be wondered at that there are
divers views and conflicting theories as to the true
nature of the zodiacal light.
We have already alluded to a yet more mysterious
phenomenon, the " Gegenschein " (counterglow), as
Brorsen called it when he discovered it some sixty
years since. It is a faint luminosity of variable size,
in general more or less of the form of an oval patch,
but occasionally lens-shaped, lying along the Ecliptic
or close to it, its longitude differing from that of the
Sun by 180°, whence its name, from its always being
in exactly the opposite part of the sky. A very
extensive series of observations has been made by
Mr. T. W. Backhouse, the well-known astronomer,
of West Hendon House, Sunderland, for more than
thirty years, and he has published his results in
Vol. II of the publications of that observatory. He
finds that the ordinary form of the Gegenschein is
nearly circular, its diameter about 7°, its centre lying
a little to the north of the Ecliptic (0°-75 N. lat.).
The Gegenschein precedes the " anti-solar point " in
the sky by 0°-6 of longitude at the most.*
Professor Barnard being at Nashville, Tennessee,
U.S.A., during the autumn of 1883, whilst searching
for comets, one night noticed a feeble luminosity in
the sky " near Pegasus." He thought at first that
this was due to local illumination, although it was
remarkably steady. The following night it was
still there, and by observation of its position for
several nights running he found that it moved
towards the east along the Ecliptic at the rate of a
degree per day. HehadrediscoveredtheGegenschein.
Following up his first observations he continued to
make numerous examinations of the object, discover-
ing various changes during the course of the year.
Fifteen years of observation convinced him that
these changes are seasonal, and are repeated annually
in the same part of the sky.
About the Gegenschein there is also a variety of
theories. Some are inclined to regard it as due to
" nebulous " matter rejected from the Earth, thus
forming a kind of tail like that of a comet. Very
little of such matter would be sufficient to produce
its feeble luminosity, which is visible only upon a
perfectly dark sky. If it be indeed true that this is
the nature of the Gegenschein, then our Earth would
be richer in appendages than has been hitherto
supposed, possessing, perhaps, a ring or rings like
those of Saturn (Jones's theory of the Zodiacal Light)
and a tail like that of a comet (the " Gegenschein ").
Professor Barnard, however, is inclined to consider
the latter as a purely atmospheric phenomenon, not-
withstanding his observations and the absence of
measurable parallax, which he admits to be a weighty
objection to such a view (" Popular Astronomy,"
No. 64). Professor Searle, whose views have been
already referred to, considers that the zodiacal
light is due to the reflection of sunlight by millions
of minute planetary bodies and particles of " cosmical
dust," too small to be seen separately. When they
are directly opposite to the Sun in the sky each of
these particles shines with a "full" disc like the
Moon in the same position, and the vast collection
of small objects fully illuminated must increase the
general luminosity of this region. In other positions
less of their illuminated sides are turned towards us,
and therefore they are not so easily visible. Being at
the same time nearest to the Earth, and full when in
opposition, we have the Gegenschein. Mr. Evershed,
of Kodaikanal, in India, explains the Gegenschein as
produced by molecules of hydrogen and helium — the
* Celestial longitude is the angular distance, measured along the Ecliptic (not along the Equator) from the first point of
Aries, in degrees and other units of angular measure. Latitude is the angular distance north or south from the Ecliptic
towards its poles.
326
KNOWLEDGE.
September, 1913.
two lightest known gases — which are driven away
from the Earth in the direction opposite to the Sun ;
but the absence of sensible parallax is a serious
objection here also, unless we suppose that these
particles are already far beyond the Moon when
they are observed. Gylden, the Swedish mathe-
matical astronomer, has shown that meteors passing
near opposition in the neighbourhood of the Earth
could follow one or other of several oscillating orbits
round the point of opposition before resuming their
course around the Earth or Sun. Even if these
minute particles were very numerous they would not
exercise any appreciable attraction upon one another
or much influence on the Earth, but still they would
present the appearance of a kind of luminous fog in
opposition to the Sun. The centre of this luminous
path would be the point in the sky directly opposite
the Sun : its outline elliptical and its major axis lying
along the Ecliptic. Since the observed deviation
from perfect circularity is but small, it must be con-
cluded that the meteors move round the Earth in all
directions, without there being many more in the
ecliptic plane than in any other.
Mr. Innes has proposed a modification of an
earlier theory to account for the Gegenschein. He
considers that the Earth is continually bombarded by
meteorites which give off " corpuscles." These
latter, repelled by the Sun and Earth together,
produce a kind of feeble tail, smaller than that of a
comet, which is visible on a dark night in the part
of the sky just opposite the Sun.
Although, as we have seen from the various
accounts and views just given, there is still con-
siderable divergence of opinion as to its true nature,
and much still remains for observation, especially in
regions more favoured than our own, yet we may
conclude that the general character of the zodiacal
light is fairly well established. It is almost certainly
due to innumerable particles of matter moving round
the Sun in elliptic orbits more or less eccentric, their
paths lying in or nearly in the plane of the Earth's
orbit in a widely extended, but comparatively thin,
zone, so that the denser part has the form of
a thin, flat sheet, like one of the rings of Saturn,
lying partly within and partly without the Earth's
orbit. As there is no definite certain limit to the
Sun's corona it is possible that the inner part of
this sheet is connected with the outer part of the
former, and so in a certain sense the zodiacal light
might be regarded as an extension of the corona (as the
late Sir William Huggins was inclined to think); but
this seems an extreme view, for we might similarly
regard the planets also as so connected. There
are not wanting proofs of the existence of a resisting
medium whose influence in former ages upon the
planetary orbits is so evident, drawing them inwards
and making their paths more nearly circular than
would otherwise have been the case ; and though
most of the material composing this medium has
probably long since fallen upon the Sun and planets,
yet there most likely remains enough of it in the vast
regions of space separating the larger bodies of our
system from one another to become visible to us by
reflection of sunlight, and perhaps also by a feeble
intrinsic luminosity, like that of the nebulae, as the
zodiacal light.
PHOTOGRAPHIC EFFECT OF CHEMICAL REACTIONS.
By J. H. VINCENT, M.A., D.Sc, and J. MARLEY, B.Sc,
London County Council, Paddington Technical Institute.
Under the above title, in Mr. Ainsworth Mitchell's
Chemical Notes in " Knowledge " for March, 1912,
an abstract of a paper by Matuschek and Nenning
(Chem. Zeit., 1912, XXXVI, 21) is given and
commented on. The results were of such a striking
nature and offered so interesting a field for further
investigation that we tried many experiments on the
same lines. Matuschek and Nenning state that many
cases of chemical action are accompanied by the
emission of light, which acts on a photographic
plate after passing through glass. Our results differ
altogether from those obtained by these authors.
In a paper on this subject recently published in the
Chemical News (March 20th, 1913), we state that
" At first some slight photographic effects were noted
which could not be traced to known chemical action
of the kind studied by Russell, and which is attributed
to hydrogen peroxide. These positive results dis-
appeared as experience was gained in protecting the
photographic plate from the action of extraneous
light. As some of the experiments have lasted
several weeks, the precautions against the accidental
entry of light to the plate cannot be too elaborate.
In all cases any vapours, and so on, arising from the
substances engaging in the chemical action must
also be prevented from acting on the plate. Apart
from the Russell effect, due to metal screens, and so
on, we have been unable to find any evidence of
action on the plates.
The reactions tested were : —
1. Action of sulphuric acid on zinc.
2. Action of hydrochloric acid on sodium-
metasilicate.
3. Action of nitric acid on lead.
4. Hardening of plaster of Paris.
5. Electrolysis of water with platinum
electrodes.
It is difficult to account for the positive effects
observed by Matuschek and Nenning. Properly
controlled experiments with vessels containing water
heated electrically and with paraffin wax heated
electrically, have convinced us that the heat produced
by chemical action is not competent to account for
the apparent positive results. We find then no
evidence of any radiation capable of acting on a
photographic plate after passing through glass."
THE MODERN EVOLUTION OF THE STEREOSCOPE.
By A. LOCKETT.
The valuable aid offered by the stereoscope to the
scientific investigator is again attracting notice.
In astronomy, photo-surveying, the surgical applica-
tions of radiography, photo - micrography, the
treatment of certain diseases of the eyes, and in
many other new and often unexpected ways,
stereoscopy places a fresh power in the hands
both of the inquirer and the expert. Even the
cinematograph is now made to give moving
pictures in natural relief — a development opening
out a wide vista of possibilities.
The stereoscope itself has been greatly improved
of late years, and a better understanding of the
principles on which it depends has led to the
production of new models embodying important
modifications. This being so, the time seems not
inopportune for a brief sketch of the modern
evolution of stereoscopic apparatus and some
consideration of those factors that have to be
studied in order to secure the maximum satisfaction
of optical and physiological requirements. Clearly
what is needed is the best practical performance,
together with the greatest possible convenience and
the least complication. These different qualities
may not be obtainable together, but that will
evidently be the most perfect instrument which
enables the truest balance to be struck between
them.
Like telescopes, most stereoscopes may be divided
into two classes, those, namely, that utilise reflection
and those depending upon refraction. A third class
which relies upon neither, but includes several
instruments or systems of unique character, may,
perhaps, most conveniently be considered first.
The earliest stereoscope, Elliott's — designed in
1834, though not constructed till 1839 — dispensed
with all optical intervention, the two pictures, or
rather diagrams — for photography was then non-
existent — being viewed direct by the observer.
The instrument thus possessed two excellent
features ; but, unfortunately, it was necessary to
cross the axes of the eyes in a somewhat
unnatural manner, which called, in many cases,
for a little troublesome practice before it could be
accomplished. On that account Elliott's stereo-
scope never came into general use.
A modified form of the Elliott instrument, devised
by the writer in 1912, may be of interest. As shown
by Figure 346, it consists of a tapering box, A, having
two oval openings at the front for the observer's
eyes and a rectangular opening at the back. In
the diagram the top is removed for clearness of
illustration. The box is blackened inside, and to
the bottom is attached a narrow piece, B, on which
slides a holder similar to those used on the ordinary
American stereoscopes. The two photographs must
not, as is usual, be transposed in mounting, but
should be allowed to remain just as they are printed
from the negative, the picture for the right eye being
on the left and that for the left eye on the right.
To use the apparatus it is held by the handle, D, and
the stereograph is moved to and fro, keeping one eye
shut, until one picture appears to fill up the aperture
in the back. On opening the other eye the com-
bined images will then usually be seen in stereo-
scopic relief, or, if not, a few further trials will ensure
this result. The principle involved is obvious.
Owing to the fact that nothing can be seen except
through the back opening, placed midway between
the two pictures, the right eye can only perceive the
left-hand picture, while the left eye beholds only the
right-hand one. At the same time they are both
mentally referred to an apparently identical position,
so that they coalesce and give the effect of natural
relief.
For a reason to be explained later, another unique
method, the parallax system of F. E. Ives, though of
much later date (1903), may not inappropriately be
dealt with next. By this highly ingenious method
each stereograph carries its own viewing arrange-
ment, so that no separate instrument is required.
In making the negative, the two slightly different
images are superposed on each other. This may be
done in various ways, but that commonly adopted is
to use on the camera a single plano-convex lens of
about three inches diameter, placing behind this a
diaphragm having two small openings two and a
half inches apart. A screen ruled with fine vertical
lines, about one hundred to the inch, is interposed
between the lens and the plate at such a distance
from the latter that it splits the two images into
a series of adjacent lines, every alternate line con-
sisting of a portion of one image only, while the
intermediate lines represent parts of the other
image. From the resulting negative, a transparency
is made and is bound up with a line screen of the
same spacing as that with which the photograph was
taken, kept at a similar distance by a cardboard
mask. On holding the bound-up transparency at
the correct distance from the eyes, usually about
twelve inches, perfect and beautiful stereoscopic
relief is perceived. Figure 348 illustrates, on a
much enlarged scale, the precise action of the ruled
viewing screen, A being the transparency, B the
screen, and C and D the eyes of the observer. It is
obvious that either eye sees only the intermediate
portions forming its own proper picture, while the
two pictures are at the same time superposed and
united. For the best result, the opaque lines of the
taking screen should be twice the width of the
transparent interspaces, as this prevents the parallax
327
328
KNOWLEDGE.
September, 1913.
lines from running into each other when developed.
If we consider any two adjacent spaces of the
composite transparency in relation to a single open-
ing in the line screen, as shown by Figure 349, the
remarkable similarity in principle to Elliott's early
apparatus will be evident. The Ives stereograph
consists, in fact, of hundreds of tiny Elliott stereo-
scopes, all inspected simultaneously. While the
results obtained are unexceptionable, there are two
obstacles to the general
adoption of this system.
One is the necessity of
precise adjustment of the
distance of the ruled screen
from the plate in relation
to the camera extension and
the separation of the two
view points, besides the
corresponding care required
in binding up the positive,
the other being the fact that
only transparencies can be
made.
Yet a third method of
stereoscopy , utilising neither
reflection nor refraction, is
the anaglyph system of
Louis Ducos Du Hauron
(1890) in which the two
pictures forming the stereo-
graph are printed, one
over the other, in red and
blue ink respectively. The
resulting jumbled combina-
tion is viewed through
spectacles containing a red
and a blue glass, or Figure 346.
similarly tinted pieces of
gelatine. Through the red
glass, the red image is invisible and the green one
appears black, while through the green glass the
reverse is the case. As each eye, therefore, sees
only its particular picture, and the two are super-
posed, stereoscopic vision results. Prints of any
size may be produced and viewed in this way, and
the stereographs evidently occupy only half the space
that would be necessary if the two pictures were
placed side by side in the usual manner. The
drawbacks are a considerable loss of light from the
presence of the colour filters, and the fact that the
prints cannot be inspected without the viewing
arrangement, as is often desired. Though Du
Hauron was undoubtedly the first to employ the
foregoing method with printed stereographs, it
should be stated that the principle was foreshadowed
by Dove in 1843, and by Rollmann in 1853, while
D'Almeida, in 1857, used a very similar system, but
with red and green glasses for stereoscopic projection
by the lantern.
Turning now to refracting stereoscopes, that of
Sir David Brewster, familiar as the old box-form
pattern of early Victorian days, comes first in order.
Initially studied by its inventor in 1844, and com-
municated to the British Association in 1849, this
instrument was not placed on the market till 1851,
when Duboscq, of Paris, undertook its manufacture.
The principle of Brewster's stereoscope is probably
so well known that explanation is almost superfluous.
A few words, however, may be desirable. The
lenses or prisms A and B (Figure 350), cut from
the two halves of a bi-convex lens and turned with
their thin edges inwards, so
refract the rays from the
two pictures C and D that
the eyes of the observer
see them converged
together, both images being
superposed at E. Since,
nevertheless, each eye sees
only its own proper half of
the stereograph, the result
is stereoscopic relief. A
more convenient form of
Brewster's instrument, de-
signed by Oliver Wendell
Holmes in 1861, with the
further improvement of a
sliding view-holder, added
by J. L. Bates in 1864, is
now in general use.
The refracting stereo-
scope has the advantages
that no light is lost and
that the image is magnified.
Counterbalancing these
merits arc the facts that in
magnifying the prints the
grain of the paper is also
enlarged, detracting from
the fineness of the image;
that only pictures of a
small and rather awkward size can be employed ;
that the instrument has to be focused to suit differ-
ences of vision ; and, finally, that a slight degree of
distortion, if not of other optical aberrations, is
present. It may also be added that some observers
have difficulty in combining the two images with
this type of apparatus.
Variations of Brewster's instrument have been
numerous. Whole lenses have, for instance, been
used, as in the telescopic stereoscope of De la
Blanchere, which resembled a pair of opera glasses
with the two tubes adjustable as to convergence. It
is not, by the way, generally known that if we look
through an ordinary opera-glass pointed wrong way
round at a stereoscopic slide, a single small image in
relief will be seen. Another interesting stereoscope,
devised by Steinhauser, had lenses contrary to those
of Brewster's apparatus, causing the optic axes to
cross, so that untransposed stereographs could be
utilised. The chief modern improvements on
Brewster's instrument, apart from the American
hood and sliding holder, have been the employment
of achromatic instead of single lenses, and provision
September, 1913.
KNOWLEDGE.
329
KNOWLEDGE.
September, 1913.
C D
Figure 348.
The Principle of Ives's Parallax Stereograph.
Figure 349.
A Diagram illustrating Analogy
between Ives's system and
Elliott's Instrument.
EA
Figure 350.
The Principle of Brewster's
Refracting Stereoscope.
Figure 351.
The Principle of Wheatstone's
Reflecting Stereoscope.
CD
Figure 354.
The Principle of Pigeon's Prism
Stereoscope.
Figure 352.
The " Reflectascope."
Figure 355.
The constructive details of Pigeon's
Prism Stereoscope.
4>
Figure 353.
Theodore Brown's pocket
Reflecting Stereoscope.
Figure 356.
The method of inspecting Pigeon
Stereographs with an ordinary
Plane Mirror.
September. 1913.
KNOWLEDGE.
331
for altering the separation between them to suit the
distance between the eyes of any observer. Such
refinements, however, are still only met with in the
higher-priced lenticular stereoscopes.
In the opinion of many, the reflecting principle
offers the fewest disadvantages, now that its earlier
constructional drawbacks have been overcome. It
is not without interest to trace the evolution of the
reflecting stereoscope, from the cumbrousness and
complexity which at first distinguished it to its
latest developments and refinements. The earliest
stereoscopic apparatus making use of reflection was
invented by Sir Charles Wheatstone in 1838 — next in
order, therefore, to Elliott's apparatus. As shown by
Figure 351, it had two plane mirrors, A and B, inclined
together at an angle of 90°, silvered side outward,
the two pictures C and D composing the stereograph
being placed one at each side, and the observer
viewing their images in the mirrors. As both images
were reflected into an identical position at E, and
thereby made to coalesce, while, at the same time,
each eye saw only its own particular picture, stereo-
scopic vision resulted. The chief drawbacks of this
arrangement were that the two pictures had to be
inserted separately ; that, if any adjustment were
needed, both pictures had to be advanced towards or
withdrawn from the mirrors simultaneously, which
involved the use of a clumsy double-threaded screw ;
that the reflected image was necessarily reversed as
regards right and left ; and that the efficient lighting
of both pictures, from two contrary directions,
presented serious difficulties. This instrument was
therefore soon superseded. It may be remarked
that, besides claiming credit for the inception of the
first reflecting stereoscope, strong ground exists for
believing that Wheatstone was aware of the principle
of — if he had not actually constructed — the
lenticular form prior even to Brewster.
There have been many variants on Wheatstone's
instrument, since it is obvious that the two prints
and mirrors may be arranged in numerous different
ways. One of these, known as the Reflectascope, is
illustrated by Figure 352. As will be noticed, two
plane mirrors are placed at A and B, joining at a
very obtuse angle. The stereoscopic slide, the back
only of which is seen in the figure, is inserted in a
holder at C, and the observer, looking over the slide,
sees in the mirrors a single picture in relief. The
chief drawback here is that the join between the
mirrors shows, though almost imperceptibly, as a
thin line across the centre of the combined image.
If the two mirrors are inclined inwards away from
the slide, instead of outwards, the arrangement
otherwise remaining the same, non-transposed
stereoscopic slides may be used. In both cases the
image is reversed as regards right and left.
It is an evident advantage that optical aids should
be dispensed with so far as possible, in order that the
eyes view the stereograph direct. Except in Elliott's
instrument, the drawbacks of which have been
pointed out, this desideratum is incapable of practical
fulfilment. There are, however, several systems in
which one eye at least regards its own picture direct.
Various suggestions to that effect were made, at
different times, by H. W. Dove, Brewster, and
Rollmann ; but, as a modern instance of efficient
performance combined with convenience, Theodore
Brown's tiny pocket stereoscope (1895), doubtless
the smallest made, may be mentioned. In this, as
shown by Figure 353, two small mirrors, A and B,
are enclosed in a case, nearly but not quite parallel
with each other. Looking through an aperture in the
case, the right eye views its proper picture by double
reflection, apparently superposed on the left-hand
picture, the latter being seen direct by the left eye.
The same idea is obviously applicable to a double
reflection prism having sides of suitable angle.
Mirrors, to give optically perfect results, should
be surface-silvered, but are then unfortunately liable
to tarnish, and are very susceptible to injury by
moisture, scratches, or abrasion. Reflecting prisms
serve all the purposes of mirrors and are free from
these disadvantages, besides being more easily
cleaned. Many prismatic stereoscopes have been
constructed, among which may be recorded that of
Girard-Teulon (1861), in which four total reflection
prisms were used, and several forms of apparatus
invented by Sir Howard Grubb (1878), in which the
two stereographic prints were mounted one above
the other, instead of side by side. In another
instrument by Grubb the two pictures of an
ordinary stereoscopic transparency were thrown in
superposition on to a concave mirror by means of a
combination of prisms and lenses, the observer, at a
suitable distance, seeing an aerial image in relief. It
may be mentioned that Duboscq and also Jequezel,
both in 1857, made stereoscopes having prisms as
well as lenses, so that both reflection and refraction
were employed. These instruments were, however,
practically modifications of Brewster's apparatus.
Whether mirrors or prisms are used, it is fairly
evident that a double reflection must involve more
loss of light, and must require a more exact adjust-
ment than a single one. There is therefore a
special advantage in the prism stereoscope invented
by Professor Leon Pigeon, of Dijon (1910), who is
also known as the contriver of the compact and
useful book-form mirror stereoscope named the
" Dixio " (1905). In Professor Pigeon's prism
stereoscope (see Figure 354) the right-hand picture,
A, is viewed direct, while the left-hand one, B, is
seen by a single reflection in the prism, C, apparently
superposed on A. It is necessary that the left-hand
print should be laterally reversed, a condition easily
fulfilled, among other obvious ways, by making the
prints in carbon, one by single and the other by
double transfer ; or, if film negatives are used, by
printing the left-hand picture from the back. As
shown by Figure 355, the apparatus consists of an
upright panel, A, supported by a narrow cross-piece,
B, the prism being mounted in a hood, C, which
screens stray light from the left eye. The prints,
which may be of quite large size if desired, are laid
flat on a table and the instrument is placed over the
332
KNOWLEDGE.
September, 1913.
central line between the two pictures, as indicated.
Large prints may conveniently be hinged together by
a tape glued across the back at the junction, in order
that they may be kept unmixed and may fold up when
not in use. For prints over 8-in.x6-in. the stereo-
scope should be raised in the hand, so that a longer
viewing distance is obtained. Besides its ordinary
purpose the model illustrated is very suitable for
viewing stereoscopic illustrations in books. Another
pattern, it may be stated, makes provision for the
inspection of transparencies and autochromes. On
the whole, the Pigeon stereoscope — the last word, so
far, in reflecting instruments — certainly seems to
offer a maximum of efficiency, combined with
extreme simplicity. The image is exceedingly clear
and brilliant, while with a front lighting absolute
uniformity of illumination is easily secured. Those
who would like to have ocular demonstration of the
principle involved may readily do so by using an
ordinary plane mirror, about eight inches or ten inches
high, supporting it in a vertical position on the line
between the two prints, the silvered surface being to
the left, as shown by Figure 347. For the purpose
of experiment an admirable anatomical study from
an exhibit in Dijon Museum, taken by M. L. Chapuis
in collaboration with Professor Pigeon, and repro-
duced by kind permission of the latter, will be found
on page 329. The effect with an ordinary mirror
will not, of course, be so good as with a surface-
silvered one, or with the prism, but will still enable
an excellent idea to be obtained of the results possible.
It may be mentioned that an ophthalmological
stereoscope on the reflecting principle has been
invented by Professor Pigeon, for the diagnosis and
treatment of strabismus, or squinting. Besides its
primary use, it may be employed for the direct study
of the problems of binocular vision ; for investigations
concerning the function of the motor muscles of the
eye and paralysis of these muscles ; for the physio-
logical fusion of colour ; for the medico legal
examination of alterations in sight, real or simulated;
and for many other purposes.
In conclusion, some remarks concerning the
relative merits of small and of large stereographs
will not be irrelevant. It has been stated by several
writers that a small print inspected at a short focal
distance gives really the same stereoscopic effect as
a larger print viewed from a greater distance. To a
certain extent this is true ; but there is a grave fallacy
in the reasoning, since the much greater amount of
detail secured in the larger picture is overlooked.
To make the matter plainer, compare the case of an
enlargement made from a small negative with that
of a large direct photograph the same size as the
enlargement. There can be no question as to which
of the two will give the more detail. The large
direct print will show many things that are not
visible in the enlargement, it being, therefore, clear
that they are absent in the small picture. Large
prints, moreover, are seen with less fatigue, make a
more definite impression, need no objectionable
magnification, may be made with lenses of a more
acceptable focal length, and are more useful for
purposes of investigation or for the deduction of
measurements.
BEDROCK:
In the current number of Bedrock the " Hermit of
Prague " makes fun of the Headmaster of Eton for
taking seriously Miss Curtis's New Mysticism, the
nature of which she explains in her book " Medita-
tion and Health." This the " Hermit of Prague "
describes as one of the numerous wholly unscientific
works on " mind-healing " that for several decades
have gained a curious vogue in the United States.
Under the title of " Mendelism, Mutation and
Mimicry," Professor Punnett very clearly sets forth
what in his mind are the leading difficulties against
accepting the theory of mimicry as explaining the
likeness between various butterflies. He charac-
terises as an enormous assumption Professor
Poulton's belief that a very slight accidental
variation on the part of a species in the direction
of a pattern which is utterly different, will be
detected by its enemies and cause them to let it
alone. He asks how an enemy endowed with such
remarkable discrimination could fail to distinguish
between mimic and model even in cases of the
closest resemblance yet recorded.
The evidence in favour of the existence of pre-
palaeolithic man is brought forward by Mr. J. Reid
Moir, and he sums up his arguments by saying that
there is one thing, and one thing only, left for the
opponents of the pre-palaeolithic implements to do
if they wish their views to be taken seriously, and
that is to subject flints to some unguided, natural
force, and produce forms indistinguishable from
those which are in dispute.
Mr. Hugh S. Elliot, . commenting upon Dr.
McDougalPs article in the previous number of
Bedrock, says that while historically and scientific-
ally Dr. McDougall is justified in applying the name
" Materialism," to his (Mr. Elliot's) published views,
the word carries with it in the public mind many
connotations which are very far from the opinions
of those who profess it. The name " Scientific
Materialism " is suggested instead and used as a
title for the article, which is an answer to Dr.
McDougall.
Among the contents of the same number is a
contribution by " A Business Man," which he calls
" The Truth about Telepathy." The writer grumbles
because Sir Oliver Lodge attributes motives to him,
but we cannot say that we admire the methods of
" A Business Man."
♦ For July, 1913.
CATALEPSY IN PHASMIDAH.
By PETER SCHMIDT.
Privat Dozent of the Imperial University of St. Petersburg.
In the following article I wish to give the results of
some observations and experiments upon cataleptical
phenomena in connection with an Indian insect —
Carausius morosus Br. v. W. — an Orthopteron of
the family of Phasmidae. The representatives of
this family are all tropical or subtropical insects of
green, grey or brown colour and protectively resemble
the stems of the plants on which they feed. The
habitat of Carausius morosus, which will breed
during any month of the year in my laboratory, so
far as I am aware, is North India and Afghanistan ;
but, five or six years ago it was imported into
Germany via Hamburg and thence came to St.
Petersburg, where it breeds now in almost all
zoological laboratories. The insects are so interest-
ing in many respects and their breeding is so easy
that it is really strange that these Indian emigrants
have up to the present been so little known in other
countries. Their biology was studied in detail by
an eminent German entomologist, Otto Meissncr,*
who published a valuable paper, but strangely did
not notice the most interesting feature about them,
viz., their catalepsy.
These green stem-like creatures with red markings
on the femora of the forelegs show generally very
little movement. They may sit motionless during'
the whole day on the stems of plants or on the sides
of a glass jar (see Figure 357), and only occasionally
do they begin to move, and then they creep in a very
lazy way. They feed generally at night, and it is
very seldom that one can see a Carausius eating
leaves by day.
The insects may be thought at first sight to be
sleeping or reposing, but closer observation and some
very simple experiments will produce the conviction
that we have to do here with a catalepsy exactly like
that artificially produced in higher animals. Indeed.it
has long been known that many vertebrates can be
hypnotised and made motionless by very simple
methods. If we lay a rabbit on his back on the
table and fix his head and his feet for a few seconds,
we shall make him cataleptic — he will lie motionless
for some minutes, and his muscles will be strained
as in a hypnotised human subject. The same thing
can be done with a crayfish — one can stand him
vertically on his head and the first pair of legs, and
he will keep completely motionless for many hours
as if bewitched.
Now if we look more carefully at a Carausius in
his quiet state we shall see that his feet and whole
body are rigid, and his muscles are strained as in
catalepsy. Indeed, if we gently take hold of a leg
with a pair of forceps, bend it, and put it in some
pose or other, we see that it keeps this pose for
a very long time, even if it is unnatural and uncom-
fortable. In the same way we can raise the head
and the prothorax of the animal and move asunder
the first pair of legs, so that Carausius takes approxi-
mately the position of a. Mantis (see Figure 359). In
such an artificial pose Carausius will stay for many
hours.
When I had detected this interesting muscular
state in the quiet Carausius I tried some other
experiments, and after a number of trials it occurred
to me, for instance, to stand the insect on its head
(see Figure 358) and to give him a still more
amusing pose which I have called the " wrestling
bridge " (see Figure 360). In one of the experi-
ments a cataleptical Carausius remained on its head
for four and a half hours ! And he showed not the
slightest signs of fatigue.
All these experiments sufficiently demonstrate that
the muscles of Carausius are really in a state which
is named by physiologists " flexibilitas cerea "
(i.e., wax flexibility). They are strained, but not
extremely as in the state of tetanus : they can be
stretched more and remain in a given position.
Expressly the same state of muscles is observed
in the cases of catalepsy or "hypnosis" in higher
animals and in man.
How strong is this rigidity of muscles is seen
from the experiment shown in Figure 361. Here a
Carausius is posed between two books with the tips
of the forelegs on the one and with the end of the
abdomen on the other. A very considerable weight
for it, in the shape of some paper strips, has been
placed on its abdomen, so that it is bent like a bow,
and, notwithstanding, it will remain in the deepest
catalepsy for one or more hours in this strange pose !
It is known that catalepsy has two distinguishing
features : (1) a cataleptical subject does not feel
pain : one may cut and sting him, and he remains
in the same state of immobility ; (2) the cataleptical
tension of muscles does not cause fatigue. And, in
fact, a cataleptical Carausius is completely feeling-
less : with sharp scissors one can cutoff its antennae
and feet, and, one after the other, all the segments of
the abdomen ; its green blood flows from the wounds,
but it stays in the same pose completely motionless.
In order to awake the insect from its hypnotic
sleep, a prolonged excitement of the nervous system is
needed. One can excite it mechanically, for instance,
by tweaking the end of its abdomen with forceps, or
by giving it electrical shocks with an induction coil.
* Zeitsch. f. wissensch. Insektenbiologie, Bd. V, 1909, Heft 1-3.
333
334
KNOWLEDGE.
September, 1913.
But the electrical shocks must be very strong : weak
ones do not awake the insect.
The strangest circumstance in the catalepsy of
Carausius is that this state arises from unknown
inner conditions. If the insect is in its active state
it is impossible to hypnotise it artificially, like a
cray-fish. One can lay the creature down, fix it
in a given position, stroke it gently, but nothing
happens : it makes responsive movements, but does
not become cataleptic. Only of its own accord and
without exterior excitement does Carausius become
so. Therefore, I have called this phenomenon
" autocatalepsy."
From a biological standpoint the autocatalepsy is
nothing more than an accommodation to a highly
developed protective resemblance. A cataleptical
Carausius is not only motionless but remains in the
same position in which the external factors — for
instance a breath of wind or a fallen twig or leaf —
have placed it. Its likeness to the inanimate
objects is increased and the insect is given an
extra chance of surviving in the struggle for
existence.
My laboratory experiments have detected also
some interesting points in the physiology of the
catalepsy of Carausius (which I have described
elsewhere *), but biological observations on this
feature under natural conditions are wanting.
Perhaps some readers of " Knowledge " living in
tropical countries will give some attention to this
new question and make some observations on other
Phasmidae. It is possible that the catalepsy is a
feature of other representatives of this interesting
family.
* Biologisches Centralblatt, 1913, April.
CORRESPONDENCE.
THE NUMBER OF DOUBLE STARS.
To the Editors of " Knowledge."
Sirs, — Mr. Bellamy is correct in stating that the number
of double stars in Burnham's Catalogue is 13,665. I do not
know how the number I gave came to be printed.
I hope you will let me remind him I found no fault with
Mr. Lewis's Catalogue. I did not depreciate his work. I
have no doubt Burnham would agree his work was incomplete,
but Mr. Lewis's is much more so in point of numbers, and
especially as it is only a reference catalogue for Struvian
stars, and, of course, does not include the very numerous
discoveries of Burnham, and is just as defective as regards
spectroscopic binaries as Burnham's.
For the rest, Mr. Bellamy merely expresses his personal
preference for Lewis's, and leaves my criticisms entirely
untouched. EDWIN HOLMES.
Hornsey Rise, N.
Sirs, — By your courtesy I offer the following conclusions
upon Mr. Holmes' reply.
1. Mr. Holmes' reply merely leaves the point unanswered —
that is, the "Standard Authority" (or Catalogue) — which I
take to be a work wherein the particular item required may
almost certainly be found. On page 293 I stated enough to
show that the Standard Catalogue of Double Stars (including
Spectroscopic Binaries) is still, and may long be, a
desideratum.
2. I demur to Mr. Holmes' statement that he found no fault
with Mr. Lewis' Catalogue, for as the latter is a definite and
complete piece of work, it would be nearly impossible to do so ;
but he most distinctly does this, by depreciation, on page 239.
3. The question of my personal opinion does not enter, as I
dealt with facts; so the matter may end and Mr. Holmes
may enjoy in print his original criticism on this point, which
was of an inaccurate, spiteful, and unnecessary character. I
have already proved the first ; the second and third were too
obvious. Personally, I may add that I have used Mr.
Burnham's Catalogue some hundreds of hours more than that
of Mr. Lewis, but not as a " Standard " Catalogue of Double
F. A.
Stars.
Oxford.
BELLAMY.
STELLAR DISTANCE UNITS.
To the Editors of " Knowledge."
Sirs, — A. J. H. seems to have overlooked the fact that
Kepler and Newton have each places assigned to them in
the Moon, and when we think of the millions of worlds waiting
to be named or numbered, there is no reason to be afraid that
there will not be worlds to be christened, if necessary, after
the earth's great men and women. A new name for " Light
Year" was not asked for in June "Knowledge" as this is
easy to understand, and simple enough. In these days of
greater and more and more wonderful scientific researches
and discoveries, when men are trying to measure " White
Nebulae" and their distances, and so on, " Andromedes,"
"Sirio Meters," " Star Ratios," " Units" have been mentioned
as measures of astronomical distances, so that there are now
several astronomical measures of length ; and when we try to
think of the unmeasurable, unknown, infinitude of space, with
all it contains, we may safely say, " More to follow."
A short easy word is needed to represent the nearest
distance of the Earth from the Moon, and the second of arc
now being divided into tenths, hundredths and thousandths,
it is time some simple short words or signs were used for them.
J. W. SCHOLES.
Grimscar," j
Huddersfield.
SELBORNE EXTENSION LECTURES.
To the Editors of " Knowledge."
Sirs, — It is one of the difficulties of the Secretaries of
local Scientific Societies and of Institutes to find, year after
year, new subjects for discussion and lecturers whom their
members have not previously heard. May I in this connection,
therefore, call the attention of your readers to a list of lectures
which I have compiled, and which is being printed in The
Selbome Magazine tor September. The various items have
in most cases been delivered before the Selborne Society, and,
in my capacity as Extension Lecture Secretary, I should be
very glad indeed to give any help that I could to local Scientific
Societies who are wanting good lectures of general interest, at
fees which they can afford to pay. I may add that in certain
cases the lecturers only wish to cover their expenses. The
subjects, as befits the Society which perpetuates the memory
of the author of "The Natural History and Antiquities of
Selborne," deal with plants and animals, with the forces of
Nature, and with Archaeology. Many of the lecturers have
series of slides illustrating other addresses than those of which
titles are given.
In places where there are no local bodies the Selborne
Society, under special circumstances, would arrange one or
more lectures, which would come under the category of
Selborne Local Lectures.
,„ „ c PERCIVAL J. ASHTON.
42, Bloomsbury Square, j
London, W.C.
September, 1913.
KNOWLEDGE.
335
CATALEPSY IN
PHASMIDAE.
Figure 357.
Carausius as its sits on
a branch.
Figure 358.
Carausius morosus Br. v. W., standing on
its head.
Figure 359. Mantis-like pose of Carausius.
Figure 360. The " Wrestling Bridge/
Figure 361. Hypnotic experiment with Carausius.
Figure 362. Carausius reclining.
336
KNOWLEDGE.
September, 1913.
Figure 363.
First Method.
Figure 365.
Third Method.
Figure 364.
Second Method.
Figure 366.
Fourth Method.
Methods of Constructing Regular Polygons,
ON THE CONSTRUCTION OF REGULAR
POLYGONS.
By H. STANLEY REDGROVE, B.Sc. (Lond.), F.C.S., and W. H. COLES.
There are simple well-known methods for con-
structing regular figures of 3, 4, 5, 6, and 8 sides
of given length,* but the construction of regular
polygons with 7 or more than 8 sides, the length
of the sides being given, is a more difficult matter.
There is a well-known method (which need not be
described here) involving the division of a semicircle
into as many equal parts as the polygon required is
to have sides, which can be used with accuracy when
the number of sides is either 2" or 3 x2" (i.e., 4, 8,
16, 32, and so on, or 6, 12, 24, 48, and so on), since
the bisection of any arc and the trisection of a
semicircle are both easily effected. When the
number of sides, however, is any other number (e.g.,
7, 9, 10, 11, and so on), this method suffers under
the disadvantage that the semicircle has to be
divided by trial.
Another method is to calculate the vertical angle
(d) of the polygon by means of the formula
x
where x is the number of sides ; or the central
angle ((j>) may be calculated from the formula
_ 360° ,
x
either of these angles is then set out. In many
cases, however, these angles are not measured by an
exact number of degrees, and cannot, therefore, be
accurately set out with an ordinary protractor.
Moreover, when x is large, an increase of 1 or
more to x produces very little alteration in the size
of either 6 or <p, so that the angles would have to be
measured with extreme accuracy for the method to
be any good. (See Table 58.)
The following method, though not new, does not
appear to be very generally known. Let A B (see
Figure 363) be one side of the required polygon.
Bisect A B in M, and at M draw M P perpendicular
to A B and of indefinite length. With centre M
and radius M A (or M B) describe an arc cutting
M P in 4. This point obviously gives the centre of
the circle circumscribing the square drawn on A B
as base. With centre B and radius B A describe an
arc cutting M P in 6. This point obviously gives
the centre of the circle circumscribing the regular
hexagon drawn on A B as base. Bisect 46 in 5 and,
commencing from 6, mark off divisions 7, 8, 9, 10, and
so on, along 6 P, each equal to 45 or 56. Then each
of these points gives, approximately, the centre of
the circle circumscribing the regular polygon, drawn
on A B as base, containing the same number of sides
as the number used to designate the point. It is a
simple matter, then, to draw the circle circumscrib-
ing the polygon desired, and to step distances equal
to A B around its circumference. In Figure 363
are shown polygons containing 5, 7, 9, and 12 sides
thus drawn. The first three are fairly accurate.
The dodecagon, however, is not satisfactory, and
the method is increasingly inaccurate as the number
of sides is increased ; for example, if one attempts
to draw a fifteen-sided figure by this method, the
result is a polygon with sixteen sides.
In the present paper we propose giving the results
of an investigation of this method, which has made
it possible to devise three similar, but far more
accurate, methods, whereby regular polygons con-
taining as many as twenty sides can be satisfactorily
and easily drawn. In the above method it is assumed
that the distances of the centres of the circumscribing
circles from the mid-point of the given side are
in arithmetical progression. Now, the length of
this distance, in any case, measured in terms of
half the side as unit, is obviously given by the
tangent of half the vertical angle of the polygon,
/ 180°\
i.e., tan ( 90° J, where x is the number of
■j n. ir ,„ 6M , /Qno 180°\
sides; thus in Figure 363, , „ = tan 90 — — ^— I
AM V 6 /
= tan 60° = 1-732 (approx.). This method
180°^
assumes, therefore, that tan ( 90°
is a linear
function of x. This is not actually the case, since
rftan(90"-1-f) .see* (90° -if)
dx *a
i.e., a quantity whose value is not constant. This
can also be seen from the figures given in Table 59.
/ 180°\
In column 2 are given the values of tan (90° — )
between x = It and .* = 20. In column 3 are
* There are also special methods for a few other polygons, but they are all tedious.
t No figures, of course, can be drawn corresponding to x — 1 and x = 1, but the values corresponding thereto are
given throughout the table for the sake of completeness.
337
338
KNOWLEDGE.
September, 1913.
tan 90° —
given the differences between consecutive values of
180°\ n . (am 180° \
). It tan (90° — — - ) were a
linear function of x, these would all be the same.
This is evidently not the case, the difference tending
to become less as x is increased. On the other hand,
the differences do not vary very much after x := 4 is
/ 180° \
passed, and if the function y = tan f 90° — ) is
graphed, the curve obtained does not differ very
greatly from a straight line after the point corre-
6
,
,
r
- /*
i
\
•
■ r
•
i
«
.
■
\
Figure 367.
sponding to * = 4 is passed. (See Graph A, Figure
367.) The above method of drawing polygons gives
the centres of the square and hexagon accurately;
that is to say, this method gives y = 1-000 when
x = 4, and y = 1 -732 when x = 6. Since an equal
increase in x (the number of sides to the polygon)
produces an equal increase in y (the distance of the
centre from the mid-point of the side) according to
this method, it follows that y =: mx -\- c, where
m and c are constant quantities. Consequently
4 m + c = 1 • 000, and 6 m + c = 1-732,
whence c = — -464, and m = -366.
Therefore y = • 366a; — ■ 464. The values of y
thus calculated are given in Column 4 of Table 59,
and the differences between them and the true
values of y (as given by tan ( 90° — J), correct to
the third decimal place, are shown in Column 5. As
is evident, these differences are comparatively small
between x = 3 and x = 9. After this they become
increasingly large, as can also be seen by comparing
/ 1 80°\
the graphs of y = tan ( 90° J and y = -366 x
— -464 (Graph B in Figure 367), so that this
method, whilst fairly accurate for polygons with less
than 10 sides, is not satisfactory when the number of
sides exceeds 9.
The distance between consecutive centres is
assumed in the above method to be -366 x half
length of side. Referring to Column 3 of Table
2, however, it is obvious that this difference, between
x=b and ^=20, is more nearly equal to ^ x half
length of side. On this fact we base the three
following methods, each of which has special
advantages. We shall refer to the method discussed
above as Method 1.
Method 2. Let A B (see Figure 364) be one side
of the required polygon. Bisect A B in M, and at
M draw M P perpendicular to A B, and of indefinite
length. With centre B and radius B A describe an
arc cutting M P in 6. This point obviously gives the
centre of the circle circumscribing the regular
hexagon drawn on A B as base (i.e., y = 1 ■ 732 when
x=6). Trisect MB (or AM) and, commencing
from 6, mark off divisions 7, 8, 9, 10, and so on,
along 6 P, each equal to J M B. These points give
the centres of the circumscribing circles. The
polygons are then drawn as in Method 1. In Figure
366 are shown polygons containing 7, 9, 12, 14, and
17 sides thus obtained. The first four are very
accurate, the last is affected by a slight error. The
equation connecting x and y for this method can be
obtained thus : Let y=mx + c. Then clearly
m — -3, and 6w 4- c = 1 • 732 ;
whence c = — -268.
Therefore y=-3x — 268. The values of y thus
calculated are given in Column 6 of Table 59, and
the differences between them and the true values of
y are shown in Column 7. In no case between
x=4 and #=20 does the difference exceed -085, so
that this method is a good method for any polygon
containing 4 to 20 sides. In every case, moreover,
save between x=3 and x = 5 (which cases are not of
importance), this difference is less than with Method 1.
Method 2 is especially accurate when the number of
sides is 11, 12, 13, 14, or 15. Graph C in Figure 367
represents the equation corresponding to y = -3x
— 268. It will be noticed how closely it lies to
/ 180°\
V=tan(90°-— ).
Table 58.
Angles of Regular Polygons.
Vertical Angle
Central Angle
X.
*=i8cr-360:-
, 360°
<t> ■
X
X
3
60°
120°
4
90"
90°
5
108°
72°
6
120°
60"
7
128° 34' (approx.)
51° 26' (approx.)
8
135°
45°
9
140°
40°
10
144°
36°
11
147° 16' (approx.)
32° 44' (approx.)
12
150°
30°
13
152° 18' (approx.)
27° 42' (approx.)
14
154° 17' (approx.)
25° 43' (approx.)
15
156°
24°
16
157° 30'
22° 30'
17
158° 49' (approx.)
21° 11' (approx.)
18
160°
20°
19
161° 3' (approx.)
18° 57' (approx.)
20
162°
18°
September, 1913.
KNOWLEDGE.
339
Method 3. Let A B (see Figure 365) be one side
of the required polygon. Bisect A B in M, and at
M draw M P perpendicular to A B and of indefinite
length. With centre M and radius M A (or M B)
describe an arc cutting M P in C. With centre A
and radius AC describe an arc cutting B A produced
in D. With centre M and radius M D describe an
arc cutting M P in 8. It can be easily shown that
this point is the centre of the circle circumscribing
the regular octagon drawn on A B as base {i.e., y
— 2-414 when * = 8). Trisect MB (or AM) and,
commencing from 8, mark off divisions 9, 10, 11,
12, and so on, along 8 P, and 7, 6, 5 along 8 M, each
equal to J M B. These points give the centres of the
circumscribing circles. The polygons are then
drawn as in the former methods. In Figure 365 are
shown polygons containing 7, 9, 12, and 14 sides
thus obtained. The first three are very accurate;
the last is affected by a slight error. The equation
connecting x and y for this method can be obtained
thus : Let y = mx +- c. Then clearly
tn -3, and 8m + c = 2-414;
whence c = —-253.
Therefore y=-3x — 253. The values of y thus
calculated are given in Column 8 of Table 59, and
the differences between them and the true values of
y are shown in Column 9. In every case after x=6,
these differences are less than with Method 1 ; but
after x=10 they are greater than with Method 2.
For polygons containing 7, 8, 9, or 10 sides this
method is the most accurate. The graph of the
equation y=-3x— -253 cannot be shown distinct
from that of _y=-3.r — 268 in Figure 367, since the
two lines practically coincide.
Table 59.
6
10
11
^_^
i
CO
0)
(J
1
Method 1.
Method 2.
Method 3.
Method 4.
X
o
■ 366-v
Errors.
•3*
Errors.
•3-v
Errors.
■3*
Errors.
c
a
g
- -464
- -268
-•253
- -3
1
— oo
-J-oo
-•098
—
+ ■065
—
+ •080
—
0
—
2
0
•577
+ •268
—
•399
—
•414
—
+ •333
3
+ •577
•423
• 634*
+ •057
•732
+ •155
•747
+ •170
•667
+ ■090
4
1-000
•376
1-000*
•000
1-065
•065
1-080
•080
1-000*
•000
5
1-376
•356
1-366*
-•010
1-309
•023
1-414
•038
1-333
-•043
6
1-732
•344
1 • 732*
•000
1 • 732*
•000
1-747
•015
1-667
•065
7
2-076
•338
2-098
+ •022
2-065
-•011
2 ■ 080*
■004
2-000
•076
8
2-414
•333
2-464
•050
2-399
•015
2-414*
■000
2-333
•081
9
2-747
•331
2-830
•083
2-732
•015
2-747*
•000
2-667
•080
10
3-078
•328
3-196
•118
3-065
•013
3-080*
•002
3-000
•078
11
3-406
•326
3-562
•156
3 ■ 399*
•007
3-414
•008
3-333
•073
12
3-732
•325
3-928
•196
3 ■ 732*
•000
3-747
•015
3-667
•065
13
4-057
•324
4-294
•237
4-065*
+ •008
4-080
•023
4-000
•057
14
4-381
•324
4-660
•279
4-399*
•018
4-414
•033
4-333
•048
15
4-705
•322
5-026
•321
4-732*
•027
4-747
•042
4-667
•038
16
5-027
•322
5-392
•365
5-065
•038
5-080
•053
5-000:,:
•027
17
5-349
•322
5-758
•409
5-399
•050
5-414
•065
5 • 333*
•016
18
5-671
•322
6-124
•453
5-732
•061
5-747
•076
5 • 667*
•004
19
5-993
•321
6-490
•497
6-065
•072
6-080
•087
6-000*
+ •007
20
6-314
6-856
•442
6-399
•085
6-414
•100
6-333*
•019
340
KNOWLEDGE.
September, 1913.
Method 4. Let A B (Figure 366) be one side of
the required polygon. Bisect A B in M, and at M
draw M P perpendicular to A B and of indefinite
/ 1ft0°
length. Now, when *=19, tan (90°— —
= 6.
almost exactly ; so that if a point 19 be marked on
M P distant from M three times the length of A B,
this will give very accurately the centre of the circle
circumscribing the regular nonadecagon drawn on
A B as base. Mark this point. Trisect M B (or
A M) and, commencing from 19, mark off divisions
along M P each equal to f, M B. These points give
the centres of the circumscribing circles. The
polygons are then drawn as in the former methods.
In Figure 366 are shown polygons containing 17
and 19 sides thus obtained. Both are extremely
accurate. The equation connecting x and y for this
method can be obtained thus: Let y — mx-\-c.
Then clearly
m = -3, and 19m + c = 6-000;
whence c = — -3.
Therefore y= -3r — -3. The values of y thus
calculated are given in Column 10 of Table 59, and
the differences between them and the true values of
y are shown in Column 11. Below .*=15, these
differences are higher than with Methods 2 and 3,
and below x = 9 they are greater than with Method 1.
This method is not recommended, therefore, for
polygons with less than 15 sides. But when the
number of sides lies between 15 and 20 inclusive, it
is the most accurate method. The graph of the
equation y = «3* — -3 is shown in Figure 367
(Graph D). It practically coincides with that of y
180°^
90°
tan
between x — 16 and x — 20.
We have not considered it necessary to continue
the investigation for polygons containing more than
20 sides, though doubtless similar methods for
accurately constructing such polygons could be
devised.
In Table 59 that method which is most accurate
for each polygon is indicated by an asterisk. If, when
using any of these methods, one has a list of errors,
such as given in Columns 5, 7, 9, and 11 of Table 59,
an even more accurate construction may be obtained
by estimating with the eye the true position of the
centre of the circumscribing circle above or below
the approximate position given by the method
employed.
SOLAR DISTURBANCES DURING JULY, IQI3-
By FRANK C. DENNETT.
During July the solar disc has shown very little disturbance,
though rather more than in the two previous months. On
eight days (2, 5, 19, 21, 22 to 24 and 27) the disc appeared
quite clear. On nine (7 to 14 and 30) spots or pores were
visible. No observations were made on the 18th, and on the
remaining thirteen days faculae were visible. The longitude
of the central meridian at noon on July 1st was 137° 20'.
No. 9. — First seen on the 9th as two spotlets, the larger
leading. On the 10th there were at least three umbrae in the
western portion of the group and two, with a dull companion,
in the eastern. The disturbance reached its maximum on the
11th, being some 40,000 miles in length; the components were
smaller on the 12th, and less in the evening than in the
morning. Only two pores were seen on the 13th, one still
remaining on the 14th. Faculae were seen in the same area
on the 16th and 17th.
No. 10. — A little group of pores seen on the morning of the
30th, which had faded greatly by the afternoon, and were
gone entirely by the next day.
On both the 7th and 8th tiny black pores and bright flecks
were visible in various places on the disc under best
conditions, but none sufficiently conspicuous to measure.
Faculae during the month were very far from being
conspicuous. There were some near the western limb on the
1st, and within the north-eastern on the 3rd and 4th. On the
20th a facula near longitude 295°, S. Latitude 35°, was
approaching the south-western limb. Faculae were within
the eastern limb on the 25th and 26th, also within the north-
eastern limb on the 28th and 29th. On the 29th faculae were
also situated at about 206°, 20° North, and 56°, 5° South.
There were faculae near the eastern limb on the 31st.
Our chart is constructed from the combined observations
of Messrs. J. Mc Harg, A. A. Buss, E. E. Peacock, W. H.
Izzard and F. C. Dennett.
DAY OF JULY, 1913.
II.
10
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8
7
1
*
4
31
SO
hf
1.
23
f
■
25.
z-,.
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2
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1
13
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15
14
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'f
30
20
10
B
9
10
&
°V
10
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30
N
FCP
1
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N
0 a » » *o a a ro ao 90 to m no 00 i»o u »» oo wj no joo ?w w no zw s> »o vo jso ?*> s* » 520 530 M »so w>
September, 1913.
KNOWLEDGE.
341
Figure 368.
Nest of the Song Thrush built against a post and lacking
one side.
Figure 370.
An old pail in which a Blackbird annually builds.
' *■
Figure 369.
A Song Thrush sitting in an old Kettle.
Figure 371.
A Blackbird's nest in an old paint pot.
342
KNOWLEDGE.
September. 1913.
Figure 372.
A Song Thrush's nest on the top of a nesting box in which
tree sparrows built.
Figure 374.
A Song Thrush's nest built in an open bracket basket
put up for the purpose.
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*"^^Sm5^^ »
SSSFP Bfe^^. * •
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iff t I) '^%
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Ml "•» 9 * ~ 4K
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Figure 373.
The nest of a Blackbird built in an open-fronted nesting box
intended for robins and flycatchers.
•"iglke 3/5.
Young Song Thrushes in a nest built on a roofed tray made
for these birds or blackbirds.
THE NESTS OF • THE SONG THRUSH AND
BLACKBIRD.
By WILFRED MARK WEBB, F.L.S.
Chairman of the Brent Valley Bird Sanctuary Committee.
Many of the blackbirds and thrushes which nested
in the Brent Valley Bird Sanctuary during the past
spring and summer built in interesting positions,
and a short account of a few of the sites will be
given here.
The first nest to which we may allude was that of
a song thrush which was built against a flat-sided
post about two feet from the ground. The interest-
ing part about the structure, however, is that there
was practically no material used on the side towards
the post, but it appeared as shown in Figure 368.
The hollow was therefore not circular and the nest
recalled that of a martin, which is built against a
wall.
In connection with the height of this nest from
the ground, it may be mentioned that both blackbirds
and thrushes have at various times actually placed
their nests directly on the earth, though until the year
1912 it was noticed that the birds were usually
unsuccessful in rearing their young. In that year,
however, a song thrush which constructed a well-
hidden nest under some brambles, brought up five
young ones, and this spring four young birds flew
from a very similar nest which probably belonged to
the same old birds.
Our second illustration (see Figure 369) shows
one of the same kind of bird sitting in an old kettle
which in previous years has found favour with robins
and with wrens. Blackbirds have chosen a similar
nesting-place in the Sanctuary, but this is the first
time that a thrush has contented itself with such
restricted accommodation. The hen bird, it may be
mentioned, like others which have chosen artificial
surroundings, was very tame, and when perching on
the branch outside the kettle would allow us to stand
within a couple of feet of it.
Four or five years ago an old pail was lodged in
the fork of a large hazel branch, and during successive
seasons since blackbirds have built in it, sometimes
rearing two broods of young ones (see Figure 370).
Another pair of these birds built a very substantial
nest in the disused paint pot which is seen in
Figure 371. But some enemy or other interfered
with the eggs and the nest was deserted.
Some years ago a thrush took possession of the
top of one of the rough closed nesting boxes with a
sloping roof put up for smaller birds, and completed
its work of building in a little over a week, but the
nest slipped off the box and came to grief.
This year, two nests were found in similar positions
and these remained quite steady, tree sparrows
taking possession of the insides of the boxes. One
of the nests is shown in Figure 372, and the box is
becoming quite an historical one. It was occupied
by the first pair of nuthatches which were recorded
as breeding in the wood, a wryneck has laid in it, as
well as tits and tree-sparrows.
Quite close at hand, another thrush brought off
her brood on the top of a hurdle inside the shed in
which the keeper was at work.
For the benefit of robins and flycatchers nesting
boxes made of hazel branches with open fronts have
been put up, and on two or three occasions have
been taken possession of by blackbirds, with complete
success. One of these, which was occupied during
the past summer, is shown in Figure 373. Once or
twice song thrushes have begun operations in similar
receptacles, but they have not completed their work,
probably because there is too little room, and as they
twist round in nest-building their tails catch against
the sides of the box.
Seeing that blackbirds and thrushes will take to
artificial nesting-sites such as have been mentioned,
and that bird lovers who were anxious for these
birds to nest with some amount of security in their
gardens had made enquiries, members of the Bird
Sanctuary Committee were led to try the experi-
ment of making special arrangements for these birds.
Both species very commonly build on the small
twigs that grow out from the lower parts of tree
trunks, and trays and baskets were made of thicker
or thinner branches and nailed up like brackets in
their positions, as well as flat trays, which were
nailed on the upper sides of horizontal branches.
Very few of the latter were used, but as the others
became weathered and the artificial look wore
off, they came to be occupied more and more
generally, until this year probably ten or a dozen
were used.
The first one of which use was made some time
ago was of the type shown in Figure 375, where the
trays were fastened to a board and supplied with a
roof of the same material. This covered bracket
tray forms a very snug nesting site and during the
winter a field-vole made a roof of moss to the
deserted nest, and bored a small round hole in the
mud lining, making himself very cosy winter
quarters. In Figure 375, just mentioned, some
young thrushes of this year can be seen.
Another type of bracket is similar to the last
described, but instead of having at the back boards
and a roof, the tray is simply fastened to two vertical
piecesof split branch, theflatsides being put againstthe
tree and those with the bark on away from it. Still yet
another kind resembles the baskets which are made
for ferns. This is shown in Figure 374 and contains
M3
344
KNOWLEDGE.
September, 1913.
a thrush's nest and eggs. A blackbird's nest in a
similar basket was begun on a Tuesday and was
seen completed with two eggs in it on the following
Sunday morning, while it may be added in this
connection that within two days of a new log box
being put up a great tit had begun to bring in
material, and before the week was out the nest was
finished and contained eggs.
Some seasons ago, two examples of the Lyne
nesting bush, which we believe is intended for
aviaries, were sent to the Sanctuary by the inventor,
and one of these put up in a hazel was occupied by
a thrush in the first year, but not afterwards. We
have pretty well exhausted the various places which
the birds with which we are dealing have chosen in
the Sanctuary, but we may mention that in The
Selbome Magazine for August a photograph is
reproduced showing a ladder hanging under the
eaves of a cottage with thirteen blackbirds' nests
built between the rungs. These were constructed in
the same season, and several of the birds were
sitting at the same time.
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
PROFESSOR NEWCOMB'S LAST RESEARCHES ON
THE MOON'S MOTION.— A pathetic interest attaches to
the volume of the American Ephemeris Papers that has lately
appeared ; for Professor Newcomb, who had given a large
portion of his life to researches on the Moon's motion, and
was the first to find the reason of the rapidly growing error of
Hansen's Tables, continued to dictate the matter of the
present volume till within a few days of his death. Some
thirty years have now passed since his earlier researches, in
which he showed that one of Hansen's large Venus terms
ought to be left out altogether, having no place in theory ; that
the mean motion and secular acceleration he used were also
wrong, and that it was necessary to introduce a large
empirical term with a period of about three centuries. These
four alterations were introduced into the Nautical Almanac
under the name of Newcomb's Corrections, and are used
there to this day. There were some who denounced their
introduction, which they called an introduction of empiricism
into exact astronomy ; this shewed a decided misconception of
the situation ; only one of Newcomb's four corrections was
empirical, the others were in accordance with theory ; besides,
Hansen's Tables were themselves just as empirical, for they
had a large Venus term which ought not to be there at all, its
coefficient being really quite insensible. In the last thirty
years many attempts have been made to find a theoretical
explanation of the great empirical term. It is now established
that it cannot be due to the action of any of the known
planets ; at least four causes have been suggested : it might be
due to a ring of planets inside Mercury's orbit, with period
nearly the same as a lunation ; or to want of symmetry in the
sun, whose rotation is nearly the same in length as a lunation
(this suggestion was made by Brown, but it does not appear
tenable in view of the great differences of rotation-time of
different zones of the sun) ; or that gravity was obstructed in
passing through matter, so that a lunar eclipse causes a
diminution in the sun's action on the moon (this is due to Dr.
de Sitter) ; or that there is some connection with the earth's
magnetism, the period of revolution of the magnetic pole being
something like three centuries.
The object of Professor Newcomb's last research was to
try to find the nature of the great oscillation with more
accuracy ; for this purpose he has used a very long series of
observations of occultations of stars ; these are capable of
more precision than meridian observations, for the disappear-
ance or reappearance is instantaneous, and can be estimated
to a quarter of a second or less. The places of all the brighter
stars in the zodiacal region have now been found fairly
accurately, and the error of the moon's place can be deduced.
I would remark that the observation of these phenomena is
one in which amateurs may well take part ; a three-inch
telescope is amply large enough ; there must be some means
of getting correct time ; one way of doing this is to receive
the wireless signals from the Eiffel Tower. Writers in Nature
have stated that they have succeeded in doing this, using an
ordinary wire mattress as collector ; a fairly good clock or
chronometer is also necessary, to measure the interval between
the occultation and the time signal.
After calculating the results given by the long series of
occultations, which extend from 1620 to 1908, Newcomb
proceeds to discuss the mean motion and acceleration, and
the form of the empirical fluctuation. He finds that a single
sine curve will not represent the fluctuation ; there is evidence
of another with a period of about sixty-four years, which has,
in fact, been introduced into the new French Tables ; the
great term is best represented by the expression
12"'95 sin { 1°-31 (t-1800) + 100°-6 }
the period being two hundred and seventy-five years; his
result of thirty years ago was
15"-49 sin { 1°-3187 (t-1800) + 93°-9 }.
The coefficient has now been reduced by 2§", and the period
lengthened by four years.
Newcomb gave a diagram of the fluctuations of the moon
from its calculated place since 1620 in the Monthly Notices
for January, 1909 ; it clearly shows the great wave and the
term of about sixty-four years, and there is an appearance of
a still shorter wave from the observations of the last century.
The work also discusses ancient eclipses of sun and moon ;
Newcomb gives little weight to the former, considering that
the evidence that any eclipse was total at a given point is not
convincing ; indeed, this is admitted by all, and weight is only
assigned to corrections which will make most of the eclipses
of antiquity agree with the narratives.
Several other astronomical constants are incidentally dis-
cussed, since this long series of occultations throws light on
them : among others the rate of change of the obliquity of the
ecliptic ; Newcomb favours Seeliger's suggestion that we
should look to the denser part of the Zodiacal Light for an
explanation of the discordance of this rate from theory, also
of discordances in the rate of motion of the perihelion of
Mercury and of the node of Venus (Newcomb had deduced
8"- 76 for the sun's parallax from the motion of Venus' node;
the accepted value now is 8" -806; the discordance may be
due to the action of the Zodiacal Light). The part of the
Zodiacal Light that seems to be gravitationally active is of
ellipsoidal form, and within the orbit of Mercury ; that is, it is
only a small part of the light that we see. but the density
doubtless increases rapidly as we approach the sun, so that
most of the mass lies inside Mercury's orbit. This would be
a more satisfactory explanation than the assumption that
gravity does not vary exactly as the inverse square. Another
suggestion for explaining the anomalies in the moon's motion
was that they might arise from changes in the rate of the
earth's rotation. Newcomb tested this question by the
observed transits of Mercury ; his earlier discussion seemed
to indicate changes that would explain half the moon's
fluctuations ; but the more complete discussion seems to
indicate no change in the rotation rate. The rather unsatis-
factory end of the entire work is that " Until the matter is
September, 1913.
KNOWLEDGE.
345
cleared up it will be impossible to predict the moon's longitude
with the precision required for astronomical purposes. We
shall be obliged to correct the moon's mean longitude from
time to time, perhaps at intervals of ten to twenty years from
observation."
THE MAGNETIC FIELD OF THE SUN.— Nature for
July 17th contains an interesting article on Professor Hale's
recent work in this direction. It will be remembered that the
hydrogen vortices round sunspots gave evidence by the
Zeeman effect (i.e., the doubling or tripling of spectral lines)
of the passage of the rays through a magnetic field, which it
was reasonable to conclude was caused by the whirling motion
of negative electrons. The present investigation has been a
search for a similar but much weaker effect due to the general
magnetic field of the sun. Great dispersion is required, as the
field is weak, and the Zeeman effect slight ; the new 164-feet
tower telescope and 75-feet spectrograph at Mount Wilson
have been used, which make one Angstrom = 4-9 millimetres ;
the distance between the D lines is 29 millimetres, or over an
inch. Full details are given in Nature of the manner of
taking and measuring the spectrograms. It will suffice to say
here that the spectrograms are divided into narrow longitudinal
strips, polarised in opposite directions, so that alternate
members of the doublets appear on alternate strips,
and the lines as a whole have an " in-and-out " appear-
ance. The shifts follow a sine-curve fairly regularly, being
0 at the equator and poles, and reaching maxima in opposite
directions at latitude 45° north and south. The maximum
displacement in either direction is about -006 millimetres.
It is concluded that the north magnetic pole of the sun lies at
or near the north pole of rotation, and that the strength of
field at the pole is about fifty Gausses. The lines belonging
to high levels of the sun's atmosphere show practically no
displacement, so it is concluded that the field falls off rapidly
as we ascend from the photosphere. It is incidentally
suggested that the tiny pores, which appear at all parts of the
sun, are incipient vortices which, under favourable conditions,
develop into spots. The whole investigation is a striking
illustration of the power of modern methods, especially in the
hands of such a master as Professor Hale. He contemplates
further researches, so as to obtain more information as to the
variation of the magnetic field at different altitudes.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
INDIAN TIMBER TREES.— The Superintendent of
Government Printing, Calcutta, is issuing a series of
extremely useful notes on Indian timbers (Forest Bulletins,
Nos. 16 to 21, price 4d. each), which can be obtained from
H. S. King & Co., 65, Cornhill, London ; Oliver & Boyd,
Tweeddale Court, Edinburgh; E. Ponsonby, 116, Grafton
Street, Dublin ; or through any bookseller. The trees dealt
with in the six bulletins just issued are, respectively, Gmelina
arborea, Pterocarpus marsupium, Terminalia tomentosa,
Lagerstroemia lanceolata, Ougeinia dalbergoides, and
Anogeissus latifolia. Each bulletin gives the distribution,
habit, and so on, of the tree, the properties and uses of the
timber, minor products, if any, and much other information, and
includes a specimen of the wood in the form of a thin section
mounted in a stout cardboard frame. The preparation of
these bulletins, and their issue at such an extremely low
price, reflect the greatest credit on the enterprise of the
Forest Research Institute at Dehra Dun, the officers of which
are responsible for their compilation, and it would be a great
boon were our home authorities to issue a similar set of notes
on British-grown timbers.
THE FAMILY HYDROPHYLLACEAE.— In the great
encyclopaedia of systematic botany, " Das Pflanzenreich,"
now being issued under the editorship of Professor Engler,
there has just appeared a monograph of the family
Hydrophyllaceae, by A. Brand (Heft 59, 210 pages. Price
M. 10.60). Though some members of the family are
cultivated as border plants (chiefly species of Netnophila
and Phacelia), the Hydrophyllaceae are not represented in
Europe, and though some species occur in all the other
continents the great majority are American, and the family is
practically concentrated in California and adjacent parts of
North America. In several respects the family is one of the
most interesting among the gamopetalous Dicotyledons. The
geographical distribution of the genera and species presents
some remarkable features, which can only adequately be
explained on the view that the distribution was formerly much
more extensive than at the present day ; the few species which
occur outside of North America — in South America, tropical
Asia, Africa, and so on — appear to be remnants of former wide-
spread genera. The systematic position and the affinities of
the Hydrophyllaceae are also of great interest. The family
is placed near the base of the Tubiflorae — the large series of
Gamopetalae including such families as Convolvulaceae,
Solanaceae, Scrophulariaceae, Labiatae, and so on. To the
Boraginaceae it presents various resemblances, such as the
roughly hairy leaves and stems, the coiled inflorescence (the
so-called " scorpioid cyme "), the presence in various forms of
scales within the mouth of the corolla-tube, and the internal
anatomy; as to the last point, the family agrees with
Boraginaceae and Polemoniaceae in having collateral bundles
of the normal type instead of bicollateral bundles with
internal phloem such as occur in the Convolvulaceae and
Solanaceae. Again, the family is separated somewhat
widely from the Polemoniaceae by the fact that the micropyle
of the seed is directed upwards (as in the Boraginaceae),
while the structure of the ovary in Hydrophyllaceae
differs from that of all the neighbouring families owing to the
characteristic large placentas, which only rarely fuse in the
centre so as to produce a truly two-celled ovary — in most
cases the placentation is parietal. Yet there is a striking
correspondence between Hydrophyllaceae and Polemoniaceae
as regards geographical distribution. During the twenty
years that have elapsed since the Hydrophyllaceae were dealt
with in Engler and Prantl's " Pflanzenfamilien," the number
of known species has increased from one hundred and seventy
to two hundred and thirty. Like all the other volumes of
" Das Pflanzenreich," this monograph is more than a mere
technical description of genera and species, the systematic
portion being preceded by an interesting general account of
the anatomy, pollination mechanisms, geographical distribution,
affinities, and so on.
BIOLOGY OF SUBMERGED WATER-PLANTS.— An
interesting resume of various recent publications on the
structure, physiology, and ecology of aquatic and marsh plants
is given in the current number (Vol. I, No. I, June) of the
new Journal of Ecology. One of the papers reviewed at
considerable length is by W. H. Brown (Philippine Journal
of Science, Vol. VIII), and deals with the relation of the sub-
stratum to the growth of the Canadian water-weed, Elodea
(Anacharis) canadensis, though the results have a general
bearing upon the biology of submerged water-plants. Brown
gives tables showing the relative growth of Elodea with and
without the addition of carbon dioxide to the water, in tap
water, and in Knop's nutrient solution, with and without soil,
rooted in and simply anchored over soil or sand, and so on,
and the results from this portion of his work are summarised
as follows : — Sufficient carbon dioxide to keep the plant grow-
ing or even alive does not diffuse from the air into the water
during winter and spring ; the substratum probably serves as
an important source of this gas. The Elodea is not dependent
on its roots for absorption of mineral salts ; the chief function
of the roots (in this and doubtless in other submerged rooted
aquatics) is to anchor the plant to the soil, which is advan-
tageous when the soil contains organic matter and gives off
carbon dioxide ; plants rooted in good soil grow better than
those simply anchored over the same soil. When carbon
dioxide was supplied by a generator instead of by the soil,
rooted and anchored plants grew about equally well; with
similar soils but no external supply of carbon dioxide, floating
plants grew better than rooted ones, the air being in this case
the source of carbon dioxide.
346
KNOWLEDGE.
September, 1913.
Further details of Brown's important work, and of various
other recent researches on the interesting aquatic flora of
ponds and streams, are given in the review mentioned above,
which extends to nine pages and deals with every important
publication on the aquatic and marsh flora during the last
two years, with references to earlier work in addition.
CUSHION PLANTS.— Another interesting article in the
Journal of Ecology for June deals with the structure,
physiology, and ecology of cushion-plants, based on an
important work by Hauri (Beih. Bot. Centralbl., Band 28),
of which the following is a brief summary. Cushion plants
are perennial, usually evergreen, more or less stunted plants
of compact and usually rounded growth and dense branching,
the branches being closely covered with relatively small stiff
sessile leaves which are either appressed or are packed
together with hairs. Hence the plant forms a living spongy
cushion characterised by firmness, compactness, and closed
growth, which reacts as a whole to the factors of the environ-
ment. Details are given of the main features of these
remarkable plants, under such headings as general form,
branching, root system, firmness and closure, and packing
material, and cushion-plants are divided into six classes
(illustrated by a full-page set of illustrations) of which
examples are given. In the general sketch of the biology and
ecology of cushion-plants the following points are noted,
(a) The capacity for absorbing and retaining large quantities
of water, serving to regulate the temperature of the plant
during alternate warming and cooling of the air, to keep the
air in and around the plant relatively moist, to make the
underlying soil moist and warm, and in some cases to supply
water directly to the aerial organs by means of adventitious
roots. (b) The crowding and overlapping of the leaves,
serving as a protection against direct insolation, and producing
wind-still and moist capillary interspaces between the
branches, thus minimising loss by transpiration, (c) The
compact growth of the branches in the cushion, which
enhances the capillary arrangement due to (6) and serves to
collect sand and other wind-borne debris as well as the dead
leaves of the plant itself, besides being the main factor in pro-
ducing the cushion habit itself with its obvious protective
advantages, (d) The packing material, which enormously
enhances the water-holding capacity of the cushion, provides
food in the form of humus, and enhances the rigidity and
hardness of the cushion. The degree of hardness attained in
some cases may be judged from the fact that in some Andine
species, such as Azorella tnadreporica, the plant turns off
a revolver shot at point-blank distance, and specimens can
only be obtained by breaking up the cushion with a hammer !
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon), F.I.C.
WILD LETTUCE RUBBER.— Mr. C. R. Fox, writing in
the Journ. Ind. Eng. Chem. (1913, V, 477), gives an
account of two species of wild lettuce which grow in the
United States, and suggests the possibility of utilising them
for the production of rubber. One of these, Lactuca
canadensis, which is popularly known as " trumpet weed,"
yields when bruised a thick milky juice, or latex, containing
over two per cent, of rubber. It also contains upwards of
13 per cent, of a brittle brown resin, which dissolves readily
in alcohol and acetic acid, and a slightly acid substance with
an intensely bitter taste. More than forty years ago it was
stated by Maisch that the juice of this lettuce contained a
bitter principle, " lettuce opium," and Mr. Fox suggests that
extraction of this drug combined with the separation of the
rubber might be found a profitable industry. Owing to the
presence of the acid bitter principle the rubber would require
washing with alcoholic alkali.
The other species of lettuce, L. scariola, is an annual
plant, the juice of which contains less rubber (1-58 per cent.)
and a smaller proportion of resin. The rubber derived from
either of these plants is stated to possess excellent physical
properties.
ACTION OF CAUSTIC LIME ON SOIL. — It is
common knowledge that soil is materially improved by
suitable additions of caustic lime, and this is usually
attributed to its neutralising the free acids in the soil and
rendering the plant food constituents suitable for absorption
by the plant. Mr. H. B. Hutchinson's experiments, however
(Journ. Agric. Science, 1913, V, 320), indicate that these
effects do not explain the whole of the results obtained in
practice through the application of lime to the soil. The
germicidal action of the lime is a material factor, and it has
been found that its action in this direction is more pronounced
than that of volatile antiseptic agents, but is less effective
than sterilising the soil by heat. The immediate effect of
adding lime is to destroy the larger protozoa and a large
proportion of the bacteria in the soil, and to decompose
organic nitrogenous compounds. After the whole of the lime
has been transformed into carbonate bacteria begin to develop
rapidly, and there is an increase in the production of available
plant foods.
These conclusions were confirmed by the results of
practical tests with different soils. For example, the addition
of 0-5 per cent, of caustic lime to a poor soil already con-
taining sufficient calcium carbonate was followed by a
pronounced increase in the crops ; while treatment of a good
garden soil with varying proportions of caustic lime up to
1 per cent, caused the first crop to be poorer, but the second
crop to be much richer than originally.
THE ACTIVE MODIFICATION OF NITROGEN.—
It has been asserted that the phenomena attributed to active
nitrogen are due to the presence of traces of oxygen, but the
Hon. R. J. Strutt shows (Proc. Royal Soc, 1913, A.
LXXXVIII, 539) that this is not the case. On the contrary,
oxygen has an unfavourable effect, and when present in the
proportion of two per cent, inhibits the reactions of the
nitrogen. In preparing the nitrogen for the action of the
electric discharge, Mr. Strutt absorbs all traces of oxygen by
means of phosphorus, and then dries the gas by passing it
first through phosphorus pentoxide and then through a tube
packed with copper gauze and cooled with liquid air. Finally,
oxides of phosphorus are dissolved by the water which rises
in the gas-holder, the latter being meanwhile covered with
black cloth to prevent the action of light upon the nitrogen.
Nitrogen thus purified and rendered active by the passage
of an electric discharge will combine with vaporised zinc,
cadmium, mercury, sulphur, and other elements to form
nitrides, which are decomposed by water, with the liberation
of ammonia. It reacts with carbon bisulphide to produce a
blue polymerised carbon monosulphide and a blue nitrogen
sulphide, while it decomposes sulphur chloride with the
formation of the ordinary yellow nitrogen sulphide. It appears
to act upon most organic compounds, liberating hydrocyanic
acid, but carbon tetrachloride is not decomposed in this way.
ACTION OF OZONE ON FIBRES.— The results of
experiments to determine the effect of ozone upon different
textile fibres are described by Mr. C. Doree in the Journ. Soc.
Dyers and Col., 1913, XXIX, 205. In each case the yarns
were exposed to the action of oxygen containing 1-5 to 2 per
cent, of ozone and their relative breaking strength and
elongation determined after various periods. In the case of
cotton and artificial silk there was but little reduction in the
strength during the first hour, but subsequently the deteriora-
tion was very rapid, and after twelve hours the breaking
strength had fallen from 30 to 50 per cent. This alteration
in the physical properties was accompanied by a chemical
change. For example, a sample of cotton-wool, containing
44-4 per cent, of carbon, showed only 43-5 percent, after the
oxidation. Flax was attacked much more rapidly than cotton,
and yielded formic acid and solid acids, but dry wool was
hardly affected after several hours' exposure to ozone in the
presence of moisture. If the wool were first soaked in water,
however, a rapid decrease in its strength and elongation was
observed, while silk under similar conditions was rapidly
attacked by ozone.
September, 1913.
KNOWLEDGE.
347
GEOGRAPHY.
Bv A. Stevens, M.A., B.Sc.
TENTH INTERNATIONAL GEOGRAPHICAL CON-
FERENCE.— This conference was held at Rome in the end
of March and the beginning of April. Unfortunately it had
been twice postponed, and the consequent was that the attend-
ance was only half that at the foregoing conference. It was
decided that all papers notified for the postponed meetings
should be read, but the authors of many of these were not
present. Several of the sections held very few meetings : in
one case only a single meeting was possible, and the sessions
were often unexpectedly short. Possibly the most interesting
discussions concerned the international map of the world on
the scale of 1 : 1,000,000. With it, as well as with other maps
on larger scales for international use, considerable progress
has been made. The important question of uniformity in the
spelling of names on maps, particularly on those of uncivilised
and polar regions, was also raised, and we may hope that
shortly satisfactory and uniform methods of spelling will be
adopted.
EXPLORATION.— The Canadian Arctic Expedition left
British Columbia in June to explore certain circumpolar
regions, notably the area of the Parry Archipelago. Reasons
based on a detailed study of tidal currents have been brought
forward by Dr. R. A. Harris for supposing the existence of
an Arctic continent, stretching from the 75th beyond the 85th
parallel, N. latitude, and lying between one hundred and one
hundred and fifty degrees W. longitude. Peary believes he
saw the outposts of such a land north-west from Cape
Thomas Hubbard, and Greely also supports Harris' opinion.
Nansen, however, thinks the area is occupied by a deep
polar basin. The expedition has been equipped and staffed
for comprehensive scientific work. The operations will be
based on Melville Island, and will be directed to exploration
of the Archipelago and to investigation of the region to the
north-west, where the supposed continent should lie. They
will occupy three years.
An elaborately equipped expedition to Eastern Turkestan,
under Italian auspices, and led by Dr. D. Filippi, is com- •
pletely organised, and will set out shortly. The leaders will
join the main party in Asia next March.
EARLY MAN IN SOUTH AMERICA.— Bulletin 52 of
the Bureau of Ethnology of the Smithsonian Institution
contains the results of the work of a party which investigated
the human remains of Argentina. The purely geological
work shows that the Pampas have been built up by wind and
rivers acting alternately, as the delta plains of Eastern China
are at present being formed. H uge deposits of loess are found.
Abundant evidence of the existence of man in Argentina at
an early date was discovered. But the men of the Pampas
were of a well-marked American Indian type, and there is
nothing to indicate very great antiquity or that man has been
primarily or independently evolved in South America. As is
pointed out, the report contains no positive evidence against
the theory of the evolution of man in that region ; nevertheless,
there is abundant evidence against it of the negative kind.
PROBABLE EFFECTS OF THE PANAMA CANAL.—
To the March issue of the Journal of the Royal Statistical
Society Professor L. Hutchinson contributes a suggestive
paper on this subject, which Professor T. Russell Smith also
discusses in the March Journal of Geography.
The eastern seaboard of the United States and the
European centres of trade on the one hand, and on the
other the markets of Pacific countries, are chiefly affected.
Professor Hutchinson points out that in the market countries
there is already considerable development evident ; they are
well on the way to supplying many of their own requirements
in food and clothing, and the main increase in imports is to
be expected in manufactured goods, notably of steel. Their
export trade is likely to develop most in vegetable products,
in meat and animal fibre, and in minerals. A statistical study
of the facts confirms the general idea that of manufactur-
ing countries Britain, Germany, and the United States will
be mainly affected ; and of these the foreign trade of the last
shows the widest growth, while that of the first is on a
downward gradient. Though the changes will not be so
fundamental as those consequent upon the opening of the
Suez Canal, Professor Hutchinson believes that whatever
modifications political causes may impose, the commercial
factors will produce an important acceleration of the advance
of the trade of the United States. Professor Smith holds
that the Canal will bring about " the greatest readjustment
of all time " and affect profoundly the volume of trade carried
by every important ocean route as well as the routes them-
selves.
VARIATION OF THE WATER-LEVEL OF LAKE
TANGANYIKA. — An attempt has been made to assign a
period and amplitude to this variation in a paper in the
Mitteilungen d. Deutschen Schutzgebieten, 1913, No. 1.
The upper limit is got from terraces marking old shores seven
to ten metres above the present surface level towards the
north end of the lake ; and it is believed that the water
reached the topmost shortly after the time of Stanley's visit
(about 1878). At this time the outlet by the Lukuga to the
Congo drainage system was silted up ; but the bar was
pierced about 1880, and there seems to be no reliable
information as to whether it has been re-formed since. At
Usumbura a post placed at the water edge some thirteen
years ago now stands twenty metres out from the shore in
• 78 metre of water, and it has been concluded that the
minimum level is about one metre below the present surface,
reached last about 1908. Thus the period is put at thirty
years, and the amplitude at eleven metres. The fall in level,
however, has been frequently checked and reversed, sometimes
for a space of years, and there is no good reason to believe
that a major rise has now set in. If definiteness is to be
assigned to the phenomenon much more exact and continuous
information must be collected over a greatly extended time.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
THE MICROSCOPIC EXAMINATION OF COAL.—
Thin sections of coal are extremely difficult to make owing to
the brittleness and softness of the material, and when made
the opacity and homogeneity of the material frequently render
the microscopic examination very disappointing. By the use
of a tough cement, however, J. Lomax (Transactions of
the Institution of Mining Engineers, Vol. XLII, Part I) has
been enabled to make very thin sections of coal, and finds
definite structures, each seam having its own special charac-
teristics. In thin section most coals are found to be laminated
with alternating bands of bright and dull material. Even the
brightest coals when sliced show this lamination. The dull
bands are chiefly composed of numerous megaspores embedded
in a ground- mass of microspores ; whilst the brighter portions
are built of the smaller microspores with highly compressed
remains of leaves and other vegetable tissues. Other coals
show compressed woody tissues, sometimes in the form of
" mother of coal," or having a resinous appearance with the
tissue preserved. Other structures are frequently seen : some
are oval and intensely resinous in appearance. These have
been named Ovalites resinosus by Mr. Lomax. In some of
the coals beautiful amber-coloured bodies of various shapes
and sizes are found, to which the author proposes to give the
provisional name of Amberites. Many species of megaspores
are found in the various coals, one species being confined
chiefly to each seam.
The author gives the results of the examination of many
Lancashire coals, and has illustrated their microscopic appear-
ance in many fine plates. The cannel coals are found to
consist of an agglomeration of microspores, with here and
348
KNOWLEDGE.
September, 1913.
there a few megaspores. Some of them grade into a material
which is nothing but a black carbonaceous mudstone. The
majority of the coals examined are humic coals, composed of
the droppings of trees and plants in the form of spores, fruits,
leaves, twigs, and sometimes fragments of flattened stems.
Mr. Lomax comes to the conclusion, contrary to some recent
opinions, that no great quantity of wood enters into the com-
position of coal ; and what there is occurs mostly in the form
of charcoal or " mother of coal." In the hardest, purest, and
brightest coals the material has been reduced to a more or
less pulpy state before carbonisation.
An interesting and important practical application of these
results has been made. The author suggests that the micro-
scopic examination of a coal-seam may be a good guide as to
the inflammability of the dust likely to be given off. Many
coals have been shown to be composed largely of the spores
of the huge Lycopods of the Carboniferous period, plants
whose descendants are the recent Selaginellas and Club-
mosses, the spores of which are known to be highly inflam-
mable. The spores in the coal have not lost their highly
inflammable and explosive nature during their long entombment,
and when released in the form of dust during working produce
a highly explosive mixture. Many coals, moreover, contain
the resinous and inflammable bodies known as Ovalites
resinosus. Hence coals rich in megaspores and Ovalites
resinosus are likely to give rise to a very explosive dust, and
this conclusion is borne out by the microscopic examination
of coals which are known to produce such a dust.
ALLUVIAL FAN FORMATIONS.— In arid regions
of high relief, such as the western deserts of North America,
there are huge deposits of rock-detritus in the form of confluent
or interdigitating alluvial fans. These fans or cones are
deposited by occasional violent torrents, and, owing to the
diminishing velocity and carrying power of the water towards
the lower levels, a more or less regular gradation occurs from
large blocks at the upstream point of the fan to fine silt in
the playas, or river-bottoms. This material is prevailingly
angular, although there may be admixture of rounded pebbles
due to the denudation of old conglomerates in the mountains
from whence the detritus is derived. When cemented these
fan-deposits are called " breccias," in accordance with current
usage ; but as A. C. Lawson points out (Bulletin of the
Department of Geology, University of California Publi-
cations, Vol. VII.), the term "breccia" is so overloaded with
meanings that it has no particular connotation suggestive of
the kind of rock to which it is applied, or its origin. Hence
Dr. Lawson proposes the new term " fanglomerate " — a
particularly ugly hybrid — for the deposits described above.
He also points out the scarcity of rocks of this kind in the
older geological formations, even after making due allowance
for possible non-recognition or disguise under other names,
and suggests that this may be explained by the supposition
that the combination of bold relief and aridity was not common
in the geological past. It is further concluded that the period
of time from the Quaternary to the present is exceptional in
geological history in respect to the coexistence of these two
conditions over a large portion of the North American
continent.
METEOROLOGY.
By William Marriott, F.R.Met.Soc.
THE "FERNLEY" SELF-RECORDING RAIN
GAUGE. — The Southport Meteorological Observatory is
considered by meteorologists to be one of the best equipped
observatories in this country. When the Royal Meteorological
Society held its Provincial Meeting at Southport in May last
year, the Fellows had an opportunity of inspecting the
Fernley Observatory and the Marshside Anemograph
Station, and also of seeing the large collection of instru-
ments at work, the great care bestowed upon them, and
the remarkably clear and valuable records obtained from
them. Mr. Joseph Baxendell, the Borough Meteorologist, in
his Report for 1912, describes the " Fernley " self-recording
rain-gauge, which he has just brought out and added to the
equipment of the Observatory. In this he has introduced a
new action of siphoning, and also added other improvements.
Figure 376 illustrates the working of the instrument.
The rain collected by an 11-inch deep-rimmed funnel [not
shown for want of space] passes through a wide pipe (C) to
the cylinder (A), raising the float (B) and a new anti-friction
wheels' pen-carrier, until 0-50 inch has fallen, when a cam
(K) throws over a rocking-weight shown, and this, by means
of a tripping-rod (J), causes the contents of a tilting-bucket
Figure 376.
Plan of the " Fernley " Self - Recording Rain Gauge.
(H) to be emptied into a water-air-pump (G, F). A i-inch
bore copper syphon (D) above the pump, and leading
from the side of the rain cylinder (A) to a trap (E), is
rapidly exhausted by the water-air-pump and, coming into
action full-bore, empties the half inch of rainfall in half a
dozen seconds, the pen returning to zero on the chart. The
water, escaping through a pipe (M), refills the tilting-bucket
(H), which is raised or "righted " not merely by the flush of
water, but also by a lever (O) that is actuated by the rocking-
weight while the latter is being raised into position (through a
pin and lever) by the weight of the descending float (B). A
detent (N) locks the rocking-weight until rainfall has caused
the pen once more to approach the top of the chart ; the
rocking-weight cannot, therefore, be accidently thrown over in
the meantime.
This new rain-gauge, which is made by Messrs. Negretti
and Zambra, works in a most satisfactory manner, and will
be of great value not only to meteorologists, but also to
engineers, surveyors, and all others who require continuous
rainfall records of a thoroughly reliable character.
September, 1913.
KNOWLEDGE.
349
THE U.S. TORNADOES OF MARCH 23rd, 1913— In
connection with the system of low barometric pressure which
crossed the United States during the latter part of March,
severe local storms occurred in portions of Kansas, Nebraska,
Iowa, Illinois and Indiana. The tornado at Omaha, Nebraska,
on Easter Sunday, the 23rd, was most destructive. From the
account in the Monthly Weather Review it seems that
ninety-four persons were killed, as well as thirty-three horses,
four cows and five mules. At Terre Haute, Indiana, the
tornado was less than two minutes in traversing the city,
during which time about three hundred and thirty houses were
demolished or badly damaged, two hundred and fifty persons
injured and twenty-one lives lost. The Weather Bureau
official states : " I have talked with several persons who were
caught in the tornado. They saw the funnel-shaped cloud
touching the ground in places and house after house crumbled
as it passed over them. They say the roar was deafening, and
I was told by several persons that it could be heard for a mile.
Many freakish things resulted : chickens were defeathered,
the clothing was drawn off a bed through a fireplace and
thence up the chimney ; in one house the linoleum was raised
off the floor ; in another a baby was lifted out of its bed,
carried a square, and laid down without injury ; toothpicks
were driven into the hard wood of a sideboard on which they
were laid, and a splinter of wood was driven through a large
phonograph horn."
ELECTRICAL STORM IN KANSAS, MARCH 23rd.—
During the greatly disturbed weather conditions referred to in
the preceding note, an unusually severe electrical storm
occurred in the three western tiers of Kansas counties on Easter
Sunday, March 23rd. From an account given by Mr. S. D.
Flora we learn that during this storm windmills, especially
steel mills mounted on wooden supports, became so charged
with static electricity than anybody touching them received a
distinct shock, and in some cases the shock was a severe one.
The observer at Tribune, Greely County, reported an instance
where sparks two or three inches long were drawn from a
wire running to a windmill. Telephone and telegraph wires
and wire fences also became charged sufficiently to give quite
noticeable shocks, and in Scott County, where the disturbance
seems to have been most severe, one case was reported where
a prairie fire was thought to have originated from electric
sparks caused by a break in a wire fence. The observer at
Scott City also reported that sparks passed from a person's
finger held near a horse's ear, and that the horse would shake
his head as though he felt the contact of the spark. These
electrical phenomena, which occurred during high south-west
to west winds, were generally experienced from early morning
until about sunset ; and during this time the air was filled with
dust and was very dry, with no precipitation during the storm,
though light rain fell in the north-western part of the State
early in the evening.
THE VELO CLOUD.— Dr. Ford A. Carpenter in his
recently published book, " The Climate and Weather of San
Diego and California," gives the following account of the Velo
cloud which is such a characteristic feature in the climate of
St. Diego. " While the velo cloud is common to the Pacific
Coast generally, and has been observed as far north as the
Straits of Fuca, this cloud reaches its perfection over the
littoral region of Southern California. The velo cloud is the
chief characteristic of the summer climate of the San Diego
Bay region. And summer should be understood as covering
all the year excepting November, December, January and
February. These four months could easily be reckoned as
spring-time. The screening of this region from the sun's rays
is so thoroughly accomplished that, during a normal summer's
day, the sun breaks through the velo cloud about 10 o'clock,
the sky clearing shortly afterwards and remaining free from
clouds until about sunset. That the velo cloud is effective as
a sun-shield, it needs only to be stated that the average of all
the July maximum temperatures since weather observations
began shows a mean of about 78°.
" The cause of the formation of the velo cloud and,
consequently, the cool summers of St. Diego, is, strange to
say, found in the hot weather in the interior of California
and Arizona. It is a unique example of the aptness of the
proverb, ' It's an ill wind that blows nobody good.' The hot
weather in the interior produces an aerial eddy (the ' low ' of
the weather map), and the difference in atmospheric pressure
between the interior and the ocean results in giving San Diego
cool, uniform days and nights, free from extremes, or what is
really the summer temperature of the Pacific Ocean. The
velo cloud should therefore be incorporated in our local
vocabulary, and it should replace the misnomer ' high fog.' "
VERIFICATION OF METEOROLOGICAL INSTRU-
MENTS.— Dr. C. Chree, in his Report of the Observatory
Department of the National Physical Laboratory, has given a
list of the instruments examined at the Kew Observatory
during the year 1912. The testing of barometers and hydro-
meters was transferred to Teddington in November, but
including these it is shown that the total number of instruments
— exclusive of watches and chronometers — examined during
the year was 40,324, an increase of 3,875 on the previous
year. The number of barometers and thermometers tested
was : —
Barometers — Aneroid
261
„ Mercury
351
Thermometers — Clinical ...
. 20,909
„ Deep Sea
55
„ Meteorological .
. 9,133
,, Standard...
107
,, Other forms
. 1,216
It is stated that the increase in the number of thermometers
tested is due in considerable measure to the introduction of
new regulations by the Home Office for cotton factories.
These factories are required by law to have dry and wet
bulb thermometers to show the hygrometric conditions
prevailing, and the new regulations required the introduction
of what was practically a new type of thermometer.
Thermometers of " other forms " are also much more
numerous than usual, owing partly to a specially large supply
of those of the type issued in connection with the chilled
meat trade.
MICROSCOPY.
By F.R.M.S.
A NEW PHOTO-MICROGRAPHIC APPARATUS.—
Although one hesitates to apply the word " new " to any form
of mechanical contrivance nowadays, seeing that any
newness about such things partakes of the nature of a fresh
arrangement of old principles or ideas, yet I venture to say
that the subject of this note presents various conveniences
which the photo-micrographer has not been able to enjoy
hitherto. I have had this piece of apparatus in practical use
for some time, and strongly commend it on account of its
convenience, ease of working, and also its efficiency.
Figure 377 shows a general view of the apparatus. It is here
seen resting on a long narrow table which was especially
designed and made for this purpose. The table bed, which is
of solid oak rather more than an inch thick, is supported by one
pillar at each end. The pillars divide so that the table rests on
four feet with castors of the form used for billiard tables. Under
the table-bed are three hanging drawers " running through "
and so get-at-able equally well from either side of the table.
The apparatus can be dismembered and all parts, except the
long square base bar, stowed away in these three drawers.
The legs of the table are fixed to the table top by nuts and
bolts, so that it can be taken to pieces for travelling.
The shoes, and so on, are all tapped with the same thread,
so that the various parts are interchangeable in position.
The photographic part consists of a five and a half feet long
straight, solid, square steel bar or base, A. A. On this slide
a number of square-fitting shoes supporting the various parts.
These shoes slide quite freely, and may instantly be clamped in
any position along the bar by means of milled headed screws
at the lower angle. The lamp end of the bar has a one-legged
350
KNOWLEDGE.
September, 1913.
shoe, B, while the camera end rests on a two-legged shoe, C.
All three of these legs are adjustable by means of screws, so
that the apparatus can be levelled on a non-level table. [This
special table is not an essential part of the outfit. A friend
has a similar piece of apparatus which is supported on a shelf
firmly bracketed to the wall, and finds this entirely satisfactory.]
Now briefly to enumerate the parts. AA, the square base
bar, arranged with its diagonals vertical and horizontal ; B,
the one-legged support, here shown resting on a thick pad of
pieces of cloth (the best absorber of vibrations that I know
of) ; D, the first sliding shoe, into which screws a round
vertical metal rod or lamp support ; E, the gas tap for
light, which by a screw can be fixed at any desired height ;
E is connected to the gas supply by a piece of rubber tubing ;
F is the holder of an inverted gas mantle. I find the " Howelite "
excellent, the light is intensely brilliant and steady, and the
mantles stand a surprising lot of rough usage. When not in
use I lift off the part F carrying the mantle and slip it on to a
piece of round wooden rod fixed into a loose triangular foot,
and keep it in one of the drawers. The next four sliding shoes
have vertical brass cylindrical pillars screwed into them. Inside
each pillar another tube slides. This latter can be fixed at any
height by a clutch screw collar, the upper part of the outer
tube being cut in two places so as to permit of the taper
thread forming a throttle grip. The first of these pillars G,
i.e., the one next the lamp, carries a " paralleliser " or
condensing lens of the crossed lens type which can be centred
by three screws and springs. H, the next pillar now un-
occupied, can hold a water tank if required. The one, J, here
carries a contrivance for holding a two-inch square colour
screen in three sides of a square rebate or groove. On the
other side of the circular head are two spring clips like those
on the stage of a microscope. These we may use for other
colour screens, and so on. J can also be used as a stage
object holder for such things as shells, fossils, suitably
mounted, and so on, when photographing with a short focus
objective without the microscope. K, is another shoe and
pillar not occupied at the moment. L, the microscope with
M, a sliding baffle tube embracing (without touching) a
projecting short tube in front of the camera, thus providing a
light-tight joint between microscope and camera, but without
contact between these two pieces. P, the bellows of the
camera, is prevented from sagging by a shoe and sliding pillar
arrangement Q. At C, we have the two-footed support (cloth
has been removed to show details). R, is a reflector or mirror
on a separate tripod foot and sliding pillar with knuckle joint
at the back, fixed at any angle at will by a screw. Thus one
can stand at any place along the table edge and yet see the
reflected image of the focusing screen in this reflector R. On
the further side of the base bar is a long steel rod. At one
end is S, a large milled head used for working the fine adjust-
ment of the microscope. At the other end, here out of sight,
but shown in Figure 383, is a grooved circular disc U. This
carries a silk cord which passes round the head, T, of the fine
adjustment. Details shewn in Figures 378-382 — V, is a pulley-
weight which keeps the silk cord taut and of even tension.
Going round the camera end of the table we get the view
shown in Figure 383, where S is the head of the fine adjust-
ment focusing rod. C is the two-legged support here shown
resting on pads of cloth. At R we see the back of the mirror
holder with screw knuckle joint, sliding pillar, and tripod foot.
At U is placed a pointed bit of white card to indicate the
grooved disc on the focusing rod which carries the silk cord
focusing tackle. In this view we see how the camera is
supported on two U-shaped or forked uprights (detachable),
so that the camera can be adjusted at any height by the
screws, b, b. By removing the butterfly screws, a, a, the two
supporting forks lift off their respective sliding shoes. The
sagging of the bellows results from removing the supporting
pillar, Q, seen in the first view.
Figure 380 shows us a little more detail as to how the
microscope is supported on the metal table, d, d, which is
fixed to its own pair of sliding shoes by the butterfly nuts,
d, d. The three feet of the microscope fit into three ring
collars, e, e, e, on the base plate. At / is shown a contrivance
like a shallow pill box lid of white card. This fits the distal
end of the sub-stage condenser at g. On this are drawn two
or three concentric circles in black lines by compasses. When
this light-adjusting cap is in situ at g it greatly helps in
adjusting the positions of the lamp, E, F, and lens, G, so as
to get an even image of the mantle mesh truly centred. If
now we open the camera back and look through the
microscope tube we can see at a glance (/ being removed, of
course), if our light, F, and lens, G, are on the axis of the
tube. At h we see a new form of speculum condenser con-
sisting of a stout clear glass rod polished at one end
and ground at the other end. Before leaving this figure
we may glance at the silk cord and then see
it in detail in Figures 378 and 382 ; this being, so far as I
know, an entirely new design. The letters T, U and V as
before refer to the milled head of the fine adjustment screw,
the grooved wheel on the focusing rod, and the weight with
pulley head. The pulley head is notched, so that it can be
easily detached. The cord is also easily lifted off T and U,
so that it remains only attached to the table d, d. It may be
noted that the edge of the table under the pulley wheels of the
table is cut away on both sides to facilitate the unshipping of
the focusing tackle. The silk cord is so arranged that at no
part of its course does the cord rub against itself, and there
is quite even tension at T. i.e., no side-pull at all.
Figures 379 and 381, show us the arrangement for the light-
tight connection between the microscope and camera. At
M we have a double tube, which, by means of a collar,
slides freely on the inner draw tube K which may or may not
carry an eye-piece as we may desire. Between these (inner
and outer) tubes goes a similar flange-mounted tube, N, on
the front of the camera as shown in Figure 381. The camera
has a loose panel front fixed by four turn buttons, so that
short-focus photographic objectives may be used without the
microscope in conjunction with certain other contrivances
which may be held over for a further note.
This apparatus has been especially made for me under the
supervision of Mr. W. R. Biss (106, Elmore Street,
Canonbury, London N.,) who is an enthusiastic amateur in
microscope and camera matters, and to whom is due the
credit of designing many of the contrivances above mentioned.
F. C. Lambert, M.A., F.R.P.S.
CORRECTION. — By an accident the blocks of two figures
on page 272 [Volume XXXVI (1913)] have been inter-
changed. The description of Figure 285 should, therefore,
read " Pisidium obtusale " which is the most globular
species, and Figure 293 should be P. millium, the squarest.
PHOTOGRAPHY.
By Edgar Senior.
PLATINUM TONING.— Although the toning of silver
prints by means of a salt of platinum has not been practised
to anything like the extent that gold toning has, the method is
nevertheless a useful one, and at the same time capable of
giving excellent results either when used alone or following
after a preliminary toning with gold. The use of platinum
salts in toning certainly dates back at least forty years, but it
cannot be considered as having been successful until the
introduction of the chloroplatinite of potassium by Mr. Willis
for platinotype printing, as attempts to use the ordinary
tetrachloride of platinum more often than not resulted in
failure. One of the earliest, perhaps, to devise a really
simple and satisfactory process of platinum toning was the
late Mr. Valentine Blanchard, who supplied a matt surface
printing paper together with the toning solutions for the prints
made upon it. Since then, however, numerous formulae
have from time to time been published for the toning of silver
prints with platinum that leave little to be desired. Collodio-
chloride papers especially give good results when toned in this
way. When the treatment with the platinum solution follows
toning with gold the following method may be recommended : —
September, 1913.
KNOWLEDGE.
351
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Figure 378.
Figure 379.
Figure 380.
Figure 381.
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Figure 383.
352
KNOWLEDGE.
September, 1913.
Figure 384.
The Fish (Scopelus glacialis) with the combined parasites,
i.e., the Parasitic Copepod carrying the Hydroid.
b c
Figure 385.
(a) The Parasitic Copepod (Sarcotretis scopeli) adult female
with egg strings ; (b) Front part of the same, dorso-lateral
view ; (c) Ventral aspect.
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Figure 387.
(a) The basal part of the Copepod with Polypes and
Medusae-buds; (b) Large Medusae-bud ; (c) Young Hydroid
colony (Iclithyocodium sarcotretis) without Medusae-buds.
Frft
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Figure 388.
(a) Cyclops stage of Sarcotretis, dorsal and lateral view ;
(b) 1st, Pupal stage, dorsal and ventral view.
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Figure 386.
Pupal stages of Sarcotretis, lateral views (a) 2nd ; (b) 3rd,
Male specimen ; (c) 4th.
Figure 389.
(a) Front part of young female in the boring stage, dorsal view .
(b) The same somewhat more developed, ventral aspect.
A Hydroid E'pizoic on a Parasitic Copepod (see page 354).
September, 1913.
KNOWLEDGE
353
Wash the prints in several changes of water and then tone in
the following bath —
Borax ... ... ... 35 grains.
Sodium Acetate ... ... 35 grains.
Water (Distilled) ... ... 7 ounces.
Gold Chloride ... ... ... 1 grain.
This solution should be made up as required, as it will not
keep. The prints are toned in this to a chocolate brown.
They are then rinsed and placed in the following bath —
Potassium Chloroplatinite
Water
Phosphorous Acid, 1-12
5 grains.
10 ounces.
75 grains.
This solution may be used over and over again until
exhausted. If the preliminary toning with gold is not carried
too far the final treatment in the platinum bath should yield a
good black. The prints after toning are well washed and
then fixed in a solution of hypo of the following strength —
Hypo ... ... ... 3 ounces.
Water ... ... ... 20 ounces.
This should be freshly prepared and about twenty grains of
soda carbonate added to it when fixing platinum-toned
prints, or, if preferred, the prints after toning may be rinsed,
and then placed in a five per cent, solution of soda carbonate
until ready for fixing. After remaining in the fixing bath for
about fifteen minutes the prints should be washed in running
water for two hours. When it is desired to tone with
platinum only without the use of the preliminary gold bath,
the following formula for the solution may be employed —
Potassium Chloroplatinite
Water
Hydrochloric Acid
i grain.
30 ounces.
J drachm.
or in place of the above we may use one containing chrome
alum, thus —
Chrome Alum ...
Potassium Chloroplatinite
Water
120 grains.
1 grain.
10 ounces.
When the prints are toned they are placed, after a slight
washing, in a five per cent, solution of soda carbonate and
allowed to remain there until all are ready for fixing.
SULFINOL DEVELOPER.— A further addition to the
already large number of bodies which act as developing
agents has recently been made by the preparation of a
substance— by M. J. Desalme — termed " Sulfinol." Those
who wish to experiment with this new compound will now
be able to do so, as it is being manufactured by the Societe
des Matieres Colorante et Produits Chimiques de Saint Denis,
105, Lafayette, Paris.
Sulfinol is a bluish-grey powder only slightly soluble in
water, but much more soluble in water containing soda
carbonate and other alkalies. It appears to contain the
sulphonic group — SO»H, and somewhat resembles Glycin in
its slowness of action. It gives soft negatives having
excellent gradation and good detail in the high lights. The
colour of the deposit verges on brown. The addition of
bromide has the effect of greatly slowing the developing
action. Sulfinol appears to be specially useful in the
development of bromide prints and enlargements on account
of the warm tones obtainable by its means. The developing
action, however, is very slow, the image taking about three
minutes to appear and requiring from seven to eight minutes
for complete development ; but the length of time required
does not appear to cause any fogging action to take place over
the lights. We append the following formula recently
published by Captain K. Hergeth in " Wiener's Mitterlungen "
for the preparation of a sulfinol developer for bromide paper —
Sulfinol ...
Soda Sulphite (Crystals)
Soda Carbonate (Anhydrous)
Water ...
10 to 15 grams.
40 to 50 grams.
30 grams.
1,000 c.c.
The soda sulphite and carbonate are first dissolved in
about 200 c.c. of water and then the sulfinol added, the
solution being finally made up to 1,000 c.c. with the addition
of water. This developer keeps well and is always ready for
use. Sulfinol may also be employed in conjunction with
hydroquinone when a developer is obtained which acts much
more rapidly and can be used for both plates and papers.
Prints made upon bromide paper may be developed with the
mixed solutions in about two minutes, — without bromide — ■
and the image will have a pleasant warm brown colour. Some
six or eight prints may be developed in the same solution,
although after the first two or three it becomes much slower
in its action. Finally, the sulfinol-hydroquinone developer
may be said to supply the means for obtaining prints of a
warm tone by direct development, and in this way is a useful
alternative to that of after-toning.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A., LL.D.
ACCESSORY CARTILAGE IN BAT'S WING.— Oskar
Torne recalls attention to an interesting extra cartilage which
lies to the outer side of the last joint of the little finger in all
Vespertilionidae. It is not bound to any other part of the
skeleton, and has considerable independent mobility. Fibrous
strands of connective tissue extend from the accessory
cartilage into the posterior margin of the wing, and probably
move it in some independent way during flight. What the
accessory cartilage really is remains obscure, and must remain
so until its development in the embryo is worked out.
EXTRAORDINARY MODE OF PARENTAL CARE
IN A FISH. — In one of the rivers of New Guinea the explorer
Lorentz found a remarkable fish, Kurtus gulliveri, whose
parental care has been described by Professor Max Weber.
In the mature male a bony process on the back of the skull
grows forwards and downwards, and forms a ring or " eye."
In this, somehow or other, a wreath of eggs is attached. Each
egg bears radiating filaments — over a hundred in number —
which unite into strings, and these form a cylindrical band.
This band passes through the bony ring, and the male carries
the eggs on the top of his head. The details of the curious
attaching filaments which fasten the eggs together have recently
been studied by Professor F. Guitel, who compares the
filaments with those of another fish, Clinus argentatus. The
adaptation is very remarkable, and one would like to know
more in regard to the manner in which the eggs come to be
fastened to the bony ring.
THE HERMIT CRAB AND ITS BORROWED
SHELL. — In his recently published memoir on the Hermit
Crab — an admirable piece of work — Mr. H. Gordon Jackson
discusses the old question whether the crustacean forcibly
ejects the mollusc. Bell argued from the frequent freshness
of the shells that the hermit must eat the mollusc out of its
home, and fishermen sometimes catch the soldier hermit crab
(Eupagurus bcmhardus) devouring a whelk. But Mr.
Gordon Jackson points out that while the argument and the
observation are both sound they do not prove that the
hermit crab attacks the living Gastropod. " In the first place
it is not very conceivable that a hermit crab would have
the strength to remove bodily, or the appetite to devour, an
extremely tough animal like the whelk." In the second place
it is well known that " the cod feeds very largely on the whelk,
and that nothing but the operculum is ever found in the fish's
stomach. The mollusc's fleshy portion (chiefly the foot and
head) must therefore be bitten off while expanded — a com-
paratively simple matter to the active and powerful Teleost —
leaving the softer (visceral) parts inside the shell." The
hermit crab may then clean up the remains and ensconce
itself in the emptied shell.
CHEMISTRY OF THE SILKWORM.— R. Inouye finds
that the chemical composition of the silkworm is greatly
354
KNOWLEDGE.
September, 1913
changed in the metamorphosis, but there is not much difference
between pupa and moth. There is no loss of nitrogen in
gaseous form during the metamorphosis. During the pupal
and moth stages the greater part of the fat accumulated by the
silkworm is consumed. In the pupal and moth stages the
waste of body protein is repaired with amino-acids, and a
part of the latter is further transformed into ammonia.
Splitting of the protein in the silkworm is caused by the action
of some proteolytic enzyme.
GEOGRAPHICAL DISTRIBUTION OF BED-BUGS.—
The family of bugs known as Cimicidae is nowadays repre-
sented all over the world — seven species in Europe, six in
Africa, five in Asia, two in Australia, and seven in America.
The two Australian species are importations by man, and the
same two have been introduced into America. Dr. G.
Horvath, of Budapest, has been recently looking into the
matter, and finds reason to believe that the common bed-bug
(Cimex lectularius) is indigenous in the Mediterranean region,
whence it has spread everywhere. The other bed-bug in the
strict sense is Cimex hemipterus, a native of tropical regions
of Africa and Asia, whence it also has been transported to
various parts of the world, such as the Antilles and Brazil.
Dr. Horvath thinks that both species of bed-bugs were, like
most of their fellow-species, parasites of bats to begin with,
and that they shifted their attention from bats to man.
A MARINE BUG. — In 1878 Baron Bonnaire discovered a
marine Hemipteron, Aepophilus bonnairei, which lives
under deeply imbedded stones at low tide. It can live for
days under water — indeed, it often occurs at levels which are
not uncovered except at very low tides. It also occurs higher
up in the Fucus zone. More information in regard to its
distribution has been recently collected by R. Lienhardt, who
points out that the insect probably gets into crevices with
imprisoned air. More than one naturalist has found it on the
back of a starfish and among worm-tubes and the like.
There are records of its occurrence from Cornwall, the
Channel Islands, Wimereux, Tatihou, Roscoff, Concarneau,
He de Re (where it was first found), and from Galicia.
FORAMINIFERA AS WORLD-BUILDERS. — From
Cambrian times or even earlier the shells of Foraminifera
have contributed notably to the crust of the earth. Messrs.
Heron-Allen and Earland have contrasted the contributions
made in different geological ages. Thus there is but a single
record of Foraminifera for the Devonian, while in the
Carboniferous they began to form enormous deposits. There
were many forms in the Cretaceous, but they did not form the
great deposits characteristic of the Foraminiferal Golden Age
in the beginning of the Tertiary times. Nowadays, as everyone
knows, a few pelagic genera are building up great deposits of
Globigerina ooze on the floor of the deep sea. In regard to
the beds of chalk ranging from the Chalk Marl to the Upper
Chalk, the authors make a useful note : " It is one of those
popular beliefs which die so hard that chalk is made up
entirely of the shells of the Foraminifera, and the textbooks
and microscopical works abound with statements to that
effect. . . . The so-called ' spheres ' of the chalk are perhaps
the origin of the belief that chalk is built up of the shells of
Foraminifera. But, whatever the ' spheres ' may be, we are
convinced that they are not Foraminifera." They may be
the firm tests of Infusorians. There are, indeed, plenty of
Foraminifera in many zones of the Chalk, but in most cases
their number is small compared with the whole bulk of
amorphous matter.
A HYDROID EPIZOIC ON A PARASITIC COPEPOD
At the Portsmouth Meeting of the British Association, held in
1911, Professor Hector Jungersen, of Copenhagen University,
read a paper on a new Gymnoblastic Hydroid (Ichthyocodium
sarcotretis) epizoic on a new Parasitic Copepod (Sarcotretis
scopeli) infesting Scopelus glacialis Ros.
Professor Jungersen very kindly allowed us to copy the
lantern slides which he exhibited at the time, and these are
now reproduced on page 352 to illustrate his interesting
description, which is as follows : —
The Hydroid coats more or less of the external part of a
parasitic Copepod deeply sunk into the body of Scopelus
glacialis (see Figure 384, page 352). It consists of : —
(1) Polypes, devoid of tentacles and growing from a
network of delicate tubes in a basal membrane without
perisarc ; and : —
(2) Medusae-buds, arising from the base of the polypes.
The largest buds possess a bell with two marginal tentacles,
four simple radial canals and a manubrium. When fully
developed they are set free as Medusae (Anthomedusae). This
new Hydroid, Ichthyocodium sarcotretis (see Figure 387),
is related to Hydrichthys minis Fewkes, epizoic on the fish
Seriola zonata. With the Hydrichthys it has to be
adopted into the family of Corynidae, as defined by Stechow
(1909). The Parasitic Copepod, Sarcotretis scopeli (see
Figure 385), represents a new genus and species of the family
Lernaeidae, allied to genera like Peroderma, Lernaeenicus,
Lernaea and Pennella.
The adult female has an elongated body, the middle part of
the long genital segment constricted into a narrow, firmly
chitinized stalk ; only the distal claviform part behind the
stalk protrudes outside the host. Cephalothorax with dorsal
shield fully preserved; two large clumsy outgrowths arise
below the margins of the shield, but no other outgrowths are
present. No eyes are visible. Antennules are linear,
antennae cheliform, the sipho large ; only one pair of
maxillipeds ; three pairs of abdominal feet, the two anterior
biramous, the posterior with a single ramus ; three free
abdominal segments with terga and sterna well developed.
It is found in the eastern part of the Atlantic, inserted into
the body of Scopelus glacialis, the body wall of which it
pierces, penetrating to the alimentary tract.
A series of Metamorphosis-stages has been found on the
same species of fish, namely,
(1) A Cyclops-stage (see Figure 388) resembling that of
Lernaea branchialis and capable of moving along on its
host and of attaching itself by means of its strong cheliform
antennae.
(2) Four Pupal-stages (see Figures 388 and 386) passively
fixed to their host by means of a hardened secretion from the
rostrum. Inside the last Pupa the copulatory form has been
observed. After impregnation the female takes up parasitic
life anew, but in a more intense form ; it pierces the skin of
Scopelus glacialis, and, gradually growing, it penetrates
through the muscles and reaches by and by the intestines of
the host.
The triple association between the Fish, the Copepod, and
the Hydroid seems to be a regular one: of fourteen adult
Sarcotretes seven carry the Ichthyocodium ; and the loss
of tentacles in the Polypes of the latter seems to show that
the Hydroid in some way or other depends on the Fish for
getting its food.
THE FACE OF THE SKY FOR OCTOBER.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 60.
Date.
Oct.
Greenwich
Noon.
Sun.
R.A.
Dec.
h. m.
0
12 31-9
S.3'4
12 5o'l
5 '4
13 8-5
7 '3
1327-0
9'i
"3 45'<S
10*9
'4 4 '9
S. 12 7
Moon.
R.A. Dec.
h. m. o
14 28-3 S. 18-7
19 23.4 S. 26*9
23 19-0 S. 5'o
2 59'2 N.21-4
7 41-7 N.26'o
12 1 3 "8 S. 2*5
Mercury.
R.A. Dec.
li. m.
■3 IS'5
13 44'2
14 12-4
14 40*0
'5 7'i
S. 8-o
11 4
14-6
'7'4
9'
'5 33'° S.2I-8
Venus.
R.A. Dec.
h. m. 0
10 36 "6 N. 9-9
(
10 59'7 7'7
(
11 22-6 5-5
(
11 45'4 3'*
12 8-1 N. o-8
12 30-9 S. 1 "6
;
Mars.
R.A. Dec.
6 38-2N.23'5
6 48-5 23-5
6 58-2 23-4
7 7'3 =3'3
7 15-8 23-2
7 23-4N. 23-2
Jupiter.
R.A. Dec.
h. m.
18 40*2
18 42*2
18 44-5
18 47-1
18 49-9
S.23'4
23-4
23-3
23'3
23-2
53-0 S.23
Saturn.
R.A. De
9*2 N.2I-2
9'I 2I"2
8"7 21*2
8'2 2I'2
7*4 2 1*2
6*5 N.2I'I
Uranus.
R.A.
Dec.
h. in.
0
20 24*6
S. 20. 0
20 24 '4
20.0
20 24-3
20 '0
20 24"3
20.0
20 24*4
20.0
20 24 "6
S.i9'9
Neptune.
R.A. Dec.
o'o
0-7
0-9
I'O
N.20-1
20 'I
20'I
20*1
20*I
N.20'I
Table 61.
Date.
Sun.
P B L
Moon.
P
Mars.
P B L T
Jupiter.
P B L, L2 T, T2
Greenwich
Noon.
Oct. 2
O 0 o
+ 26-2 +6'6 348-2
26*4 6'3 282'2
26*4 6*0 216*3
26-3 5-6 150*3
25-9 5-2 84*4
+ 25*4 +4'8 18*4
0
+ -7'S
- 7'5
-21-5
-15-6
+ 9'i
+21-9
0 a 0 h. m.
— 20'9 +5*4 299-2 4 iof
i9'8 6-3 251-5 7 26 c
i8'6 7*1 203-9 10 41 e
17-4 7-8 156-4 1 17 111
16-3 8-4 rog'i 4 32 in
-i5'3 +9'° 6" '9 7 45 *
0 & * Q h. m. h. m.
— 5*2 — 1"6 253-5 no'2 2 56 e 6 54 e
5-4 1-5 322-1 140-7 10 54« 6 4«
5'6 i'5 3°'7 '71'2 9 1 ' 5 '3'
5'9 «*J 99'2 20I'S 7 9e 4 23 '
6-2 1-5 167-7 *3i'9 S 16 e 3 33 e
-6'5 —1-5 236-1 262-1 3 24 e 2 43«
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Mars, T is the time of
passage of Fastigium Aryn across the centre of the disc. In the case of Jupiter, h± refers to the equatorial zone; L2 to
the temperate zones; Ti, T2 are the times of passage of the twozero meridians across the centre of the disc; to find inter-
mediate passages apply multiples of 9h 50jm, 9h 55\m respectively.
The letters m, e, stand for morning, evening. The day is taken as beginning at midnight.
The asterisk indicates the day following that given in the date column.
The Sun continues his Southward march, but with slacken-
ing speed. Sunrise during October changes from 6.1 to 6.53,
sunset from 5.39 to 4.35. Its semi-diameter increases from
16' 0" to 16' 9". Outbreaks of spots in high latitudes should
be watched for.
Mercury is an evening star. It reaches greatest elongation
(23i° E) on November 2nd, but, being South of Sun, is not
well placed for observation by Northern observers. Illumina-
tion diminishes from Full to %. Semi-diameter increases
from 2i" to 3".
VENUS is a morning star, rising 3 hours before the Sun.
Semi-diameter diminishes from 6" to 5i". At beginning of
month f of disc is illuminated ; at end of month A- Being
North of Sun it is favourably placed for Northern observers.
The Moon.— First Quarter 7d lh 46m m ; Full 15d6h 7mm ;
Last Quarter 22d 10" 53ra e. New 29d 2h 29m e. Apogee
12d 3h e, semi-diameter 14' 44". Perigee 28d 4h m, semi-
diameter 16' 36". Maximum Librations, 5d 8° W, 5d 7° N,
20d 7" S., 21d 6° E. The letters indicate the region of the
Moon's limb brought into view by libration. E. W. are with
reference to our sky, not as they would appear to an
observer on the Moon.
Mars is a morning Star, in Gemini, semi - diameter
4i", defect of illumination over a second. It will reach
Opposition early in January, so the season of observation
is beginning. The North Pole is now turned towards us.
Table 62. Occupations of stars by the Moon visible at Greenwich.
Date.
Star's Name.
Magnitude.
Disappearance.
Reappearance.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.
'9'3-
h. m.
h. m.
Oct. 2
BAC4867
6-4
5 56 e
77°
—
—
„ 4
BAG 5603
60
5 2 e
100
6 18 e
273°
„ io
39 Aquarii
6-2
7 32 «
16
8 34 «
277
,, II
45 Aquarii
6-1
0 1 1 in
69
1 15 m
224
„ 13
BAC57
6'3
5 53 *
i'5
6 9<
l8l
„ 14
e Piscium
4-S
7 i5'
79
8 ii«
211
„ 16 ...
27 Arietis
64
6 1 e
"3
6 37 *
194
„ 17
66 Arietis
6-1
9 59 e
94
II 0 e
213
„ 19
BAC 1648
6.4
11 13«
44
0 10* m
289
„ 21
BD + 26°i48i
7-0
—
—
8 59 «
234
M 2I
BAC 2383
6-5
10 21 e
49
II 2 e
3'4
„ 28
BD-8°3456
6-8
4 58 "'
242
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
The asterisk indicates the day following that given in the date column.
355
356
KNOWLEDGE.
September, 1913.
Jupiter is now rather low in the West. Polar semi-
diameter, 17i" in mid-October.
Table 63.
Day.
West.
East.
Day.
West.
East.
Oct. I
432 O
I
Oct. 17
43
0
12
,, 2
43
J
2«I«
,, 18
42
O
3«i»
. 3
43i
J
2
>■ 19
421
O
3
- 4
24
J
13
„ 20
4
0
r3
. 5
21 O
43
., 21
1
0
32 4»
, 6
o
1234
,, 22
1
0
14
, 7
I
J
24
•> 23
312
0
4
, 8
32 O
14
,, 24
3
0
124
. 9
3i O
4 2#
.. 25
0
43«H
, io
3 0
24
„ 26
21
0
34
, n
2
1
134
•1 27
0
2134
, 12
21 O
43
,, 28
1
0
324
> i,3
4 O
123
,. 29
23
0
41
. 14
41
0
32
>. 30
34t
u
. IS
432
J
1
„ 3i
43
0
12
, 16
43>2 O
Configuration at 6h 30mm for an inverting telescope.
Satellite phenomena visible at Greenwich, ld 8h 22ra I. Tr.
I., 9h41m I. Sh. I.; 2d 5h 37m I. Oc. D., 8h 4m 36s II. Ec.
R. ; 9h 12m 41s I. Ec. R. ; 3d 6" 29m I. Sh. E. ; 7d 5h 57m
III. Tr. I., 9h 16m III.Tr. E. ; 9d 7h 33m I. Oc. D. ; 10d6h5m
I. Sh. I., 7h 5m I. Tr. E., 8h 24m I. Sh. E. ; lld 5h 25m II. Sh.
E., 5h 36m 30s I. Ec. R. ; 13d 7h 44m IV. Sh. I.; 16d 7h 54m
II. Oc. D. ; 17J 6b 44m I. Tr. I., 8h lm I. Sh. I.; 18d 5h 9m
II. Sh. I., 5h 25m43BIII. Ec. D., 5h 29m II.Tr.E., 7h31m 33s
I. Ec. R., 8h 1B II. Sh. E., 8h 44m 34s III. Ec. R. ; 21d 5h 24m
IV. Oc. D., 8h 43m IV. Oc. R. ; 5h 19m II. Tr. I., 5* 56m I.
Oc. D., 7h 44™ II. Sh. I., 7h 47m III. Oc. R., 8h 10m II. Tr.
E. ; 26d 5" 31m I. Tr. E., 6h 45m I. Sh. E. ; 27d 5h 18m 31s II.
Ec. R. ; 30d 5h 44m IV. Sh. E. All these are in the evening
hours, the planet setting before midnight. Attention is called
to the double eclipses of 2d, 18d, 25d. On the 25th there is
only one satellite visible outside the disc. Satellites 1, 2, 4,
are all near together on 30th.
Saturn is a morning star, in Taurus, in a good position for
observation. Polar semi-diameter 9". P. is — 4°-9; ring
major axis 46", minor 20£". The ring is very widely open.
It is of interest to examine the exact amount of overlap
beyond the planet's pole.
East Elongations of Tethys (every fourth given), 2d 0h-6m,
9d l"-8e, 17d 3h-0w, 24d 4h-2e, Nov. ld 5h-4m; Dione (every
third given), ld2b-3c,9d 7h-4e, 18d 0h-4m ; 26d 5h-4m; Rhea
(every second given), 3d 7h- 9c, 12d8h-7c, 21d9b-5e, 00d 10h-2e.
For Titan and Iapetus E.W. mean East and West Elonga-
tions; I. Inferior (North) Conjunctions, S. Superior (South)
ones. Titan, ld7h-4e I., 5d 3h-8eW. ; 9J3"-2e S., 13d 6h-le
E., 17d 5h-9de I., 21" 2h-3e W., 25d lh-5e S., 29d 4h-le E. ;
Iapetus, 20d 7h-4ra I.
Uranus is an evening star. Semi-diameter, lj". About 2° S.
of p Capricorni.
Neptune is a morning star.
Meteor Showers (from Mr. Denning's List) : —
Radiant.
Date.
R.A. Dec.
July to Oct. ...
355 + 7°2
Swift, short.
Aug. to Oct. 2
74 + 42
Swift, streaks.
Sep. 28 to
Oct 9
320 + 40
Slow, small.
Oct. 2
230 + 52
Slow, bright.
,, 4
tio + 79
Slowish.
„ 8
77 + 31
Swift, streaks.
,, 8-14 ..
45 + 58
Small, short.
14
133 + 68
Rather swift.
15
3i+9
Slow.
,, 18-20 ...
92 + 15
Swift, streaks.
23
1 00 + 13
Swift, streaks.
„ 29
109 + 23
Very swift.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R.A. will be made four hours, of which two
hours will overlap with the following one. Thus the present
list includes R.A. 22h to 2h , next month 0h to 4h, and so on.
Table 64. Non-Algol Stars.
Star.
Right Ascension
Declination.
Magnitudes.
Period.
Date of Maximum.
X Aquarii
h. m,
22 14
a
-2: -3
7'6 to 11
d.
315
July 31.
TX l'egasi
22 14
+ 13 -2
8'5to 9' 2
123
July 20, Nov.
20.
S Lacertae
22 25
+ 39-8
8-0 to 12- 5
237\5
fuly 29.
K Lacertae
22 39
+ 41 '9
8'3 to 139
299-8
July 1.
U Lacertae
22 44
+ 54 '7
8-510 9- i
659
J«iy 5-
S Aquarii
22 52
-20 -8
8-o to 14- 5
279-7
July 25.
SS Andromedae
23 8
+ 52 "4
8-9 to 9-6
1658
Aug. 5.
TY Andromedae
23 10
+ 4" '3
8-2 to 96
144
Oct. 19.
W Pegasi
23 is
+ 25 '8
7 to 13
342'6
Aug. 13.
S Pegasi
23 16
+ 8-4
7 3 to 13- 1
3I7-5
Aug. 10.
R Aquarii
23 39
-15 -8
60 to IO' 8
387-16
Oct. 6.
V Cephei
23 52
+ 82 -7
6-2 to 70
362
Nov 20.
K Cassiopeiae...
23 54
+ 50 -9
48 to 13- 2
43i'6
July 21.
Y Cassiopeiae...
23 59
+ 55 2
8-4 to 139
410
Nov. 22.
SS Cassiopeiae
0 5
+ 51 'I
8-5 to 11- 7
139-6
Sep. 6.
TCeti
0 17
-20 -5
5-4 to 69
280-6
Oct. 16 (min.)
T Cassiopeiae...
0 19
+ 55 -3
67 to 12- 5
443'°
Oct. 7.
TU Cassiopeiae
0 22
+ 5° -8
7.7 to 85
59
Oct. 29.
TU Andromedae
0 28
+ 25 "5
7-7 to 11
317
Oct. 27.
RX Cephei
0 43
+ 81 -5
7-4 to 79
130
Oct. 24 (min.)
RV Cassiopeiae
0 48
+ 46 9
8 to 13
327
Oct. 24.
ZCeti
1 2
- 1 '9
8-81013-5
184-5
Oct. 6.
S Piscium
1 13
+ 8-5
82 to 14-7
404-45
Sep. 6
X Cassiopeiae
1 5i
+ 58 -8
8'4 to 12.2
367-0
Nov. 22.
(3 Lyrae minima Oct. 13d 9he, 26d 7he, Period 12 21 -8h.
Algol minima Oct. ld 4h 21™e, 10d 6M8mm, 13d 3h 37mm, 16d 0h 26mm, 18* 9h 15me, 21d 6h 3me, Period 2d 20 -8h.
THE PLUMAGE QUESTION.
Nearly thirty years have now passed since an organised
effort was begun in this country to discourage the fashion of
wearing the plumage of beautiful wild birds. The late Mr.
George Musgrave, in the year 1885, founded the Selborne
Society for the preservation of birds of beautiful plumage ;
rare and useful birds ; and pleasant places.* About the
same time, namely, on December the 18th of that year,
the Rev. F. O. Morris wrote to The Times advocating the
formation of a Plumage League and this became the plumage
section of the Selborne Society. From the comments made
by the Editor of The Gentleman's Magazine upon a letter
received from Mr. Musgrave, we gather that the latter had
learned the difficulty of enforcing protective Acts and relied
upon persuasion to overcome the results of fashion.
A prospectus of the Selborne Society, dated December,
1885, states that its object was to discourage the wholesale
destruction of birds, and that the trade had plenty of material
available "in the feathers of birds killed for food, the
game birds of the world, and of birds farmed or protected
for their plumage." The support which the Society got
from public men like Tennyson, Avebury, Leighton, John
Ruskin, and Robert Browning, as well as from many lady
members of the aristocracy, enabled it to wield considerable
influence, and to arouse an interest in the preservation of
birds.
One result of this was that in the year 1889, a special
Society (now the Royal Society) for the Protection of Birds
was brought into existence. Its object that bears upon
the plumage question reads as follows : — " To discourage the
wanton destruction of birds and the wearing of feathers of
any bird not killed for the purposes of food, other than the
Ostrich, but to take no part in the question of the killing of
game birds and legitimate sport of that character." Of recent
years the energies of this Society have been directed towards
obtaining legislation which will prevent the importation of
plumage, but none of the Bills which have been produced have
become law ; for it is obvious that without some international
agreement, the trade in feathers, which is not an incon-
siderable one, belonging to this country would simply be
transferred to the Continent.
In the meantime fashions which call for feathers still
prevail, and the killing of birds goes on. A moment's thought
shows that it is to the interest of the plumage trade that the
supply of feathers for which there is demand should not fail
through the extinction of the species producing them. The
result of domesticating the Ostrich has been little short of
marvellous from the commercial point of view, and it seemed
possible that if the naturalists and the traders were to
find some common programme, even if their ultimate objects
were by no means the same, something might be done to save
species in immediate danger of extermination.
Mr. S. L. Bensusan, the well-known writer, and the Secretary
of the Selborne Society happened to discuss the matter
informally, and the latter brought it before the Council of the
Society which empowered him and Mr. Holte Macpherson to
confer with others including members of the trade. The
result, after much delicate negotiation, was the formation of
the Committee for the Economic Preservation of Birds. On
this body there are members specially appointed by the
Selborne Society and also by the London Chamber of
Commerce. The British Ornithologists' Union has accepted
the invitation to appoint a delegate, but the Royal Society for
the Protection of Birds has not yet done so. As will be seen
from the list which we print below, many of the leading
zoologists have joined the Committee which is hard at work
collecting information bearing on the question.
Quite recently (on August the 4th) another Bill was brought
before the House of Commons forbidding the importation of
any plumage except that of Ostriches and Eider Ducks.
Licences may be granted for the importation of specimens
for museums and for scientific research, but no provision is
made for the obtaining of feathers by fly-fishermen. The bill
is open to the same objection as has been raised in previous
cases ; moreover, plumage forming part of wearing apparel
can be brought in by the owners, and birds may be imported
alive. If any attempt is made to bring in living specimens
for trade purposes the amount of mortality will be very great
and the result of the bill if it becomes law will be to encourage
the killing of British birds for their plumage, though the
Secretaries of State and the Lord Lieutenant of Ireland are
given power by the Bill to make orders for the protection of
wild birds independently of County and Borough Councils,
probably with an eye to remedying the possible evil results
to which allusion has just been made.
THE COMMITTEE FOR THE ECONOMIC
PRESERVATION OF BIRDS.
F. G. Aflalo, F.R.G.S., F.Z.S.
t+S. L. Bensusan.
Professor Gilbert Bourne, D.Sc, F.R.S., Sec. L.S.
(University of Oxford).
Walter E. Collinge, M.Sc, F.L.S., F.E.S.
Professor A. Denny, M.Sc. (University of Sheffield).
fC. F. Downham (Member of the London Chamber of
Commerce).
F. Martin Duncan, F.R.P.S., F.R.M.S.
+G. K. Dunstall (Member of the London Chamber of
Commerce).
Professor James Cossar Ewart, M.D., F.R.S. (University
of Edinburgh).
Professor F. W. Gamble, D.Sc, F.R.S., F.Z.S., (University
of Birmingham).
Professor J. Stanley Gardiner, M.A., F.R.S., F.Z.S.
(University of Cambridge).
Professor Marcus Hartog, M.A., D.Sc, F.L.S. (University
College, Cork).
W. D. Henderson, M.A., B.Sc, Ph.D. (University of
Bristol).
Professor J. P. Hill, D.Sc, F.L.S., F.Z.S. (University of
London).
Matthew Davenport Hill, M.A., F.Z.S. (Eton College).
H. Knight Horsfield.
COLLINGWOOD INGRAM.
tLouiS Joseph (Member of the London Chamber of
Commerce).
fProfessor H. Maxwell Lefroy (Imperial College of
Science),
+A. Holte Macpherson, M.A., B.C.L., F.Z.S. (Vice-
President of the Selborne Society).
Professor A. Meek, M.Sc, F.L.S. (University of Durham).
|P. Chalmers Mitchell, LL.D., D.Sc, F.R.S. (Secretary
of the Zoological Society of London).
tC. E. Musgrave (Secretary of the London Chamber of
Commerce).
Professor Robert Newstead, M.Sc, F.R.S., A. L.S.
(University of Liverpool).
■(Hubert H. Poole (Librarian of the Selborne Society).
Hugh Scott, M.A., F.L.S. (University Museum of Zoology,
Cambridge).
tW. Lutley Sclater, M.A. (British Ornithologists' Union).
C. G. Seligmann, M.B., F.R.C.P. (University of London).
The Rev. Thomas R. R. Stebbing, M.A., F.R.S., F.L.S.
Professor D'Arcy W. Thompson, C.B., D.Litt. (University
College, Dundee).
H. W. Marett Tims, M.A., M.D., F.L.S., F.Z.S. (University
of London).
I [Wilfred Mark Webb, F.L.S., F.R.M.S. (Secretary of the
Selborne Society).
W. Percival Westell, F.L.S., M.B.O.U.
Marcus Woodward.
The Honorary Secretaries, who may be addressed c/o The
Selborne Society, 42, Bloomsbury Square, would be very glad
to have the names of others who would care to join the
Committee.
* The Gentleman's Magazine, December, 1885, page 619.
t Members of the Executive Committee. { Honorary Secretaries.
357
REVIEWS.
CHEMISTRY.
Practical Agricultural Chemistry. — By S. J. M. Auld,
D.Sc, F.I.C., and D. R. Edwardes-Ker, B.A., B.Sc.
243 pages. 32 illustrations. 8-in.X5-in.
(John Murray. Price 5/- net.)
The authors of this handbook call attention to the fact that
students at agricultural colleges frequently finish their course
without having grasped the essential connection between their
laboratory work and the chemical changes in Nature which it is
intended to make clear. For this reason they have dwelt fully
on the qualitative examination of plant products, which in their
experience is likely to be of more service to the general student
than the study of quantitative methods. On this point, however,
we should be inclined to differ from them, since there can be
little doubt qualitative chemistry gains much by being taught
quantitatively. It must not be inferred from this that
quantitative work is neglected, for full outlines are given of
methods of analysing plants and their constituents, soils,
fertilisers, and feeding stuffs, and dairy products, the ground
covered being that required for the London B.Sc. degree in
Agricultural Chemistry. In general these methods are
accurate and up-to-date, although inaccuracies may be noted
in certain places. For example, in the determination of the
Iodine value by Hiibl's method insufficient time is allowed
for the absorption, and the iodine value given for linseed oil
(172) is far lower than is usual when a longer time is allowed.
A little more space might have been given with advantage to
some special subjects, such as, for instance, the analysis of
water and the difficult problem of interpreting the analytical
results. „ . .,
C. A. M.
A Text-book of Experimental Metallurgy and Assaying. —
By A. Roland Gower. 163 pages. 50 illustrations.
7§-in.X5-in.
(Chapman & Hall. Price 3/6 net.)
Metallurgical processes are too often learned by rote with-
out any thorough understanding of the chemical reactions
upon which they are based. Such rule-of-thumb methods
may give good results with the more common ores, but leave
the metallurgist at a loss when he is called upon to assay
minerals of unusual composition. The author of this book,
therefore, rightly lays stress upon the necessity for the
student to learn the chemistry of metallurgy, though he
assumes that some elementary knowledge has already been
acquired. The book has been considerably enlarged since
its first appearance many years ago, and now covers the
ground required for the Lower Examination of the Board of
Education in this subject. The exercises are simply described
and good diagrams are provided where necessary, so that the
book should prove most helpful to beginners. Among the
various assays is included a section on the examination of
fuels, including the determination of the calorific value. The
value of this would have been increased by directions for
obtaining an average sample, which is one of the chief
difficulties in the analysis of coal. „ . ,,
C. A. M.
An Introduction to the Chemistry of Plant Products. —
P. Haas, D.Sc, and T. G. Hill, A.R.C.S., F.L.S. 401 pages.
9§-in.X6-in.
(Longmans, Green & Co. Price 7/6 net.)
The aim of this book is to enable students of botany and
vegetable physiology to understand the nature of the chemical
changes that take place in plants, and the biological meaning
of those changes. The principal groups of chemical con-
stituents in plants, such as fats, carbohydrates, pigments,
proteins, and enzymes are, therefore, described at some
length, their chief qualitative reactions and methods for their
estimation being also outlined in each of the sections. As a
rule, the analytical methods given are full enough for a
trained chemist to follow without having recourse to another
work, but in some instances either too much or too little
detail is given. This is notably the case in the section dealing
with the analysis of the fats and oils, where the directions are
more than are required for understanding the meaning of an
analysis, but are not sufficient to obviate the need of reference
to other books. For instance, since the analytical methods
are given at length, tables of the values of the principal
vegetable oils and fats should have been added as an aid to
the interpretation of the results.
In this connection it may be noted that the insoluble
bromide test, devised by Hehner and the present reviewer, is
here incorrectly described as the " hexabromide test," whereas
the evidence points to the compound being the bromide of a
mixed glyceride and certainly not a hexabromide. But these
are only minor defects in a most valuable book, which ought
to find a place upon the shelves of every agricultural chemist
and botanist. It should be added that there is an excellent
index, and that full references are given in footnotes to the
authorities quoted in the text.
C. A. M.
GEOGRAPHY.
Maps and Survey. — By Arthur R. Hinks. 206 pages.
24 illustrations. 8f-in.X 5i-in.
(The Cambridge University Press. Price 6/- net.)
Those interested in Geography, and particularly those
connected with the teaching of the subject in universities and
colleges, have to thank Mr. Hinks for two valuable contributions
this year to the available literature on the practical side of
the science. Except for official publications of this country
and the United States, the systematic works on maps and
map-making in English have been special treatises by pure
mathematicians, or articles in the encyclopaedias. In " Maps
and Survey," as in " Map Projections," the demand on the
mathematics of the reader is not large, and the special needs
of the geographer have been kept in the forefront.
The present volume consists of chapters on Maps, Map
Analysis, Route Traversing, Simple Land Survey, Compass
and Plane Table Sketching, Topographical Survey, Geodetic
Survey and Survey Instruments. There are numerous illus-
trations, mostly of a high order, and the student who can
handle and examine the instruments and engage in simple
exercises easily devised will obtain from this cheap and well-
written book training of a nature his predecessors found it
difficult to acquire.
No doubt the parts on plane-table and theodolite work will
appeal most to this class of reader, and both are interesting
and well done. Here, as throughout the book, the author
indicates the possibilities and particular applicabilities of each
instrument, the errors permissible, and methods of obtaining
accuracy. We were struck, for example, by the treatment of
resection and the triangle of error in plane-table survey, and
the adjustment of rounds of angles taken by the theodolite.
Geodesy is a branch of the science of Geography that is not
widely studied or appreciated, and the most interesting
chapter on Geodetic Survey should do much towards develop-
ing a wider and more intelligent knowledge of this fascinating
subject. For Geographers and Geologists alike the theory of
Isostasy has no little importance and the present volume
presents a useful introduction to it.
We found the first two chapters a little " slow " ; and yet
they contain a great deal of useful matter which can be got
at by the much slower process of examining maps of many
kinds of details. To learn intelligently the maps must be
studied, but the book provides valuable fore-knowledge and a
guide to the work. It is difficult to see how some dullness
could be avoided.
In Chapter IV., a slight alteration of the text would
conduce to readier grasping of the method of simple levelling.
358
September, 1913.
KNOWLEDGE.
359
On page 101, the figure of the prismatic compass is given as
Plate X1I1 instead of Plate XIV, and on page 102 the special
graduation of the card of the prismatic compass might be
more fully treated; on page 129, the phrase, "distance
= s tan 0" should read "distance is s cot 0" unless there
is something wrong in the text ; and on page 148 is not
stated that the correction — H2/2L is an approximation to
— L (1 — cos 0). In a new edition doubtless these and
other slight matters will be amended with advantage to a very
ORNITHOLOGY.
excellent book.
A. S.
HORTICULTURE.
Garden Work. — By William Good, F.R.H.S. 359 pages.
38 plates. Numerous figures.
(Blackie & Son. Price 5/- net.)
This is a good practical book written by a practical man
who nevertheless has a theoretical knowledge of his art, and
does not forget in appropriate places to say something about
the structure of plants and their physiology. The bulk of the
book, however, deals with cultivation. Definite instructions
are given under the heading of each kind of vegetable or
flower, and what is of considerable importance and value is a
short list of selected varieties which the author specially
recommends. Cultivation in window boxes, in frames, and
in greenhouses, is also dealt with. There is a chapter on
propagation and another on hybridisation and cross-breeding,
while, after some words on the eradication of weeds and the
aims of floral decoration, the book is completed by the
consideration of the birds and insects of the garden and plant
diseases. We are glad to see that the author suggests that
advantage should be taken of birds which do good by
destroying pests and that they should afterwards be prevented
where possible from doing harm to fruit by netting the trees
and bushes. A number of good diagrams have been
introduced, with a series of photographic illustrations and
some coloured plates. These add considerably to the
attractiveness of the book, which we heartily commend to our
readers. ^ M> ^
NATURAL HISTORY.
A Naturalist in Cannibal Land — By A. S. Meek. 238
pages. 36 illustrations. 9-in.X6-in.
(T. Fisher Unwin. Price 10/6 net.)
Apart from being a stirring narrative of fortune and
misfortune in collecting natural history specimens in out
of the way parts of the world, Mr. Meek's book is in a way
autobiographical ; for it shows how he became a collector and
the way in which the desire for adventure caused him to take
up the career which he has so successfully followed. Of
course, a good deal of the book is occupied with an account of
the various finds of birds and butterflies which were
discovered and sent home to Tring Museum for Mr. Walter
Rothschild, but we get a very good idea of some of the habits
of the natives; for instance, in the New Guinea Hill Country,
when the traveller is on a journey, the natives of a village will
know that he is coming many days before he gets there, and
in the following way. The villages are built as a rule on the
tops of spurs, and early in the morning a crier will go to a
selected spot and sing across the valley to the next village.
As soon as an answering cry is received the crier will chant
the news he wishes to convey. Generally the message is
repeated twice, and, if necessary, it will be sent on to other
villages. The account of the position of women is of interest,
for in some places it appears that they are becoming emanci-
pated so far as to be able to choose their own husbands, and
it is amusing to read how, on one or two occasions, Mr. Meek
interfered on their behalf and became a matchmaker.
It is curious that Mr. Meek should have had so little trouble
as he did with the natives, but he seems to have been most
discreet in his treatment of them.
Among the interesting photographs which illustrate the
book is one of an albino Native Child from the Trobiands.
Another shows the Papuan kiss, which consists of the rubbing
together of noses.
W. M. W.
The Food of some British Wild Birds. — By Walter E.
Collinge, M.Sc, F.L.S., F.E.S. 109 pages. 8i-in.X5i-in.
(Dulau & Co. Price 4/6.)
Mr. Walter E. Collinge has made a really valuable contri-
bution to economic ornithology, which is the outcome of much
keen observation, and it is to be hoped that in the near future
a very great deal more scientific evidence will be produced in
this country, as to the good and harm which wild birds do.
Mr. Collinge is also to be congratulated on his freedom from
bias, and though it is possible that everyone will not agree
with his findings, seeing that the habits of birds vary very
considerably in different places and under different conditions,
he has afforded a most useful basis for argument.
Three thousand adult birds and three hundred nestlings
were examined, and twenty-nine species are discussed. Lists
are given of the articles of diet by eating which the birds may
be deemed beneficial, injurious or neutral, and then the whole
question is summed up. We give Mr. Collinge's conclusions
in each case.
Missel Thrush. — Should be kept down in fruit-growing
districts for four months of the year; it does more harm
than it does good in the rest.
Song Thrush. — Cannot be regarded as anything but very
beneficial to the fruit grower and horticulturalist.
Blackbird. — One of the most destructive birds which the
fruit-grower has to contend with.
Whitethroat. — The bulk of the food consists of injurious
insects.
Blackcap. — Mr. Collinge thinks that if this bird becomes
numerous it will be a very undesirable orchard pest.
We should like for sentimental reasons to hear a better
account of this bird.
Great Tit, Blue Tit and Wren. — Distinctly beneficial to
the fruit grower.
Goldfinch. — The worst that can be brought against this
species is that it probably aids in the distribution of
weed seeds.
House Sparrow. — If it were no commoner than the Robin
it would more than compensate for the harm which
it does.
Chaffinch. — For two months or more does great harm to
sprouting corn ; it requires reducing in numbers.
Linnet. — A harmless bird.
Bullfinch. — In fruit-growing districts it should be destroyed.
Yellow Bunting. — Generally speaking may be regarded as
beneficial.
Starling. — Considerably reduced in numbers, would regain
the good name it has borne in the past, and prove
a most useful bird to the farmer.
Jay. — An almost neutral factor.
Magpie. — Beneficial to the farmer.
Jackdaw. — The good which it does far outweighs the harm.
Rook. — Not particularly beneficial ; but its usefulness might
be considerably increased were it less numerous.
Lark. — Does more good than harm.
Bam Owl. — A most valuable bird to the agriculturist and
perfectly harmless otherwise.
Brown Owl. — Deserves all protection.
Kestrel. — The benefits this bird confers on agriculture
far outweigh the harm that it occasionally does to
young game.
Sparrowhawk. — Mr. Collinge shows that this bird is useful
apart from its fondness for game and poultry, but for
the latter reason does not advocate any protection.
Wood Pigeon. — No quarter should be shown to this bird.
One remembers, however, that in a discussion at the British
Association Meeting at Dundee last year it was pointed out
that when the corn eaten by this bird after the harvest had
been gathered in was not counted in, the balance — which,
according to the calculations of a careful observer was
previously against it — was turned in its favour.
360
KNOWLEDGE.
September, 1913.
The Stock Dove. — Condemned by Mr. Collinge.
Plover. — It would be difficult to exaggerate the value of
this bird to the agriculturalist.
These extracts will show Mr. Collinge's well-considered
opinions, but we would urge all those who are interested in
birds, from whatever point of view, to get Mr. Collinge's book
and study all the interesting details and information contained
thefein- W.M.W
PHYSIOLOGY.
Anaphylaxis. — By Charles Richet (Paris). Translated by
J. Murray Bligh, M.D., with Preface by T. R. Bradshaw,
M.D., F.R.C.P. 266 pages (including Bibliography).
7-in. X5-in.
(Constable & Co. Price 3/6 net.)
It it only eleven years since that strange and interesting
condition known as Anaphylaxis was first discovered and
described by the author of the monograph before us. Already
an enormous literature on the subject has grown up, but
Professor Richet, the pioneer, is still the greatest master of
his subject, as every page of this interesting book testifies.
Anaphylaxis may be described as " the modification of the
cells of an organism by the injection of a dissimilar albuminoid
substance, so that they seem to react with greater intensity on
the repetition of the injection," and is of great importance in
these days of serum treatment for diphtheria, cellulitis, and
other conditions. If, as was described in a recent number of
this Journal, after an interval of from a few weeks to two or
three years, a second injection of the serum of the same
animal is administered, serious symptoms of poisoning often
rapidly develop, and in some cases prove fatal. It is also
probable that those curious cases in which ordinary articles of
diet such as eggs, pork, strawberries, asparagus, shellfish, and
so on, in some people give rise to symptoms of poisoning, are
to be explained in somewhat the same manner.
The book is clearly and ably written, and should prove of
the greatest possible value to those working at this subject.
A very complete Bibliography is included.
S. H.
RADIOACTIVITY.
Beyond the Atom. By John Cox, M.A. 151 pages.
13 figures. 6i-in.X4i-in.
(The Cambridge University Press. Price 1/- net.)
This volume, No. 65 of the " Cambridge Manuals," contains
an interesting and succinct account of the modern science of
radioactivity and the theory of the disintegration of the atom,
which may justly be regarded as the central doctrine of this
science. Except for the occasional use of an unexplained
technical term or two (e.g., "Faraday tube of force"), the
book is well adapted to the needs of general readers. Mr.
Cox clearly indicates the broad lines of evidence for the
disintegration theory and its advantages over the " helide "
hypothesis, which in the light of so much evidence can now
hardly be regarded as in any sense tenable. As Mr. Cox says,
" the chemist . . . has been compelled to look ' beyond the
atom,' and in the words of Blake —
' To see a world in a grain of sand
And heaven in a flower ;
To grasp infinity in the palm of the hand,
And eternity in an hour.' "
There is a statement on page 46, however, which will
certainly prove misleading, as seeming to indicate that the
products of radioactive disintegration are not elementary, for
which there is, of course, no evidence, and which is not, I
think, what Mr. Cox intends to say.
There is an interesting chapter on " The Objective Reality
of Molecules." No doubt the Brownian movement, especially
in the light of Perrin's wonderful investigation, does endow
molecules with more reality than heretofore, and the word
" objective " is not out of place. But lest we interpret this
term in too metaphysical a sense, we must remember that
Berkeley's arguments concerning the nature of the existence
of the material world still remain ; and in the last analysis it
is clear that the world of science is a purely conceptual
world — that it is a great hypothesis, a machine, as it were,
produced by the mind in order that the mind may deal easily
with its sense-impressions. But on the other hand, of course,
if this view limits the meaning of "objectivity," it does
nothing to invalidate physical science or to deny its truth,
pragmatically understood.
H. S. Redgrove.
ZOOLOGY.
The British Parasitic Copepoda. — By Thomas Scott,
F.L.S., and Andrew Scott, A.L.S. Vol. II. Copepoda
Parasitic on Fishes. 72 plates. 9-in. X6-in.
(Dulau & Co. Price 25/- net.)
In our July number we noticed the text of the latest
publication of the Ray Society, dealing with the British
Parasitic Copepoda. The present volume, which is issued
to subscribers for the year 1913, contains the excellent
plates — more than half of them coloured — the majority of
which have been drawn by Mr. Andrew Scott from specimens
examined by the authors. ... ,, ...
W. M. W.
The Wanderings of Animals. — By Hans Gadow, F.R.S.
150 pages. 17 maps. 6i-in. X5-in.
(The Cambridge University Press. Price 1/- net.)
The distribution of animals is a question which calls up all
sorts of interesting matters. On many of these Dr. Gadow
is able to touch in the first part of his book, which shows how
animals have spread and how long they have taken to do so.
Some attractive calculations are incidentally given with regard
to the human species. In England the population doubles
itself in fifty years, and if this was to go on, a thousand years
hence the whole land surface of the globe would not afford
sufficient standing room for the sixteen hundred and sixty million
millions of people that would then exist. It is absolutely
certain that the origin of man dates back into the Pliocene,
and if we assume that the human race started as the traditional
Adam and Eve pair in that period, the rate of increase
necessary to account for the present total population would be
so small as to render the calculation quite preposterous.
Dr. Gadow gives figures which show that the rate of propaga-
tion has been always as large as it is now all over the world.
The second half of the book consists of brief accounts of
the distribution of selected groups of animals, and contains a
large amount of useful information in a small compass.
W. M. W.
NOTICES.
PLANT PROTECTION. — Arrangements are being made
to hold a Conference on this subject in London on September
the 19th. Those interested in the subject who would like to
attend are invited to communicate with the Editors of
" Knowledge " at 42, Bloomsbury Square, London, W.C.
CLASSES IN PHOTOGRAPHY.— Mr. Edgar Senior's
elementary and advanced classes in photography at the
Battersea Polytechnic begin again at 7.30 p.m. on September
the 30th, and at the South-Western Polytechnic, Manresa
Road, Chelsea, on September 22nd.
THE BRITISH ASSOCIATION.— This year's meeting
will be held at Birmingham, under the Presidency of Sir
Oliver Lodge, who will give his address on the 10th of
September. The Railway Companies, on production of a
voucher signed by the Secretary of the Association, will grant
reduced fares, and Birmingham can now be reached on the
new Great Western line in exactly two hours from Paddington.
From a time-table sent to us by the Divisional Superintendent,
we learn that trains depart at 9.10 and 11.5 a.m., and 1.0,
2.35, 4.0, 6.0, and 8.0 p.m.
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
OCTOBER, 1913.
DARK-GROUND ILLUMINATION AND ULTRA-
MICROSCOPIC METHODS IN BOTANY.
By S. REGINALD PRICE, B.A. (Cantab.)
During the last few years, and more especially
since the introduction of the ultra-microscope in the
early part of the century by Siedentopf and
Zsigmondy, the application of methods of dark-
ground illumination to high-power work has
received much attention, while many interesting and
important observations have been made by the
use of the methods. The work which has been
done in botanical research is probably compara-
tively little known, but nevertheless the method
seems likely already to become an important one in
studying various aspects of the plant cell and also
in other directions indicated below. The results,
moreover, are of general interest to the biologist as
well as to the specialised plant physiologist, and, in
view of this, a short account of some of the observa-
tions already made may be of sufficient interest
to justify this article.
Only a very brief account of methods can be given
here, and at the outset it must be emphasised that
a distinction must be made between methods of
dark-ground illumination and the method of the
ultra-microscope. The latter term is best confined
to the method devised and used by Siedentopf and
Zsigmondy — the illumination of the object (coloured
glass, colloidal solutions, and so on) by a lateral
beam of light, perpendicular to the optical axis of
the microscope.
Dark-ground illuminators are sometimes also
called ultra-microscopes, but this terminology should
not be used, although it is true that at times they
can render visible, particles which are below the
limits of visibility in direct illumination.
An apparatus for demonstrating ultra-microscopic
particles is always a dark-ground illuminator, but
the converse does not necessarily hold. Certain
forms of sub-stage illuminators are now on the
market, which give a very intense concentration of
the light in a small area, and these are chiefly used
for studying ultra-microscopic particles. Such are the
Cardioid condenser of Zeiss and the Ultra-condenser
of Leitz. Possibly the term " ultra-microscope "
should not be applied to these, if it be desired to
keep a special name for Siedentopf and Zsigmondy's
apparatus, but Leitz's term " ultra-condenser " would
be suitable.
It is important to notice that most of the high-
power dark-ground illuminators, do render visible
ultra-microscopic particles under certain conditions.
For further particulars the pamphlets of Leitz
and Zeiss should be consulted, as well as works on
the microscope, which, however, will not include
361
362
KNOWLEDGE.
October, 1913.
descriptions of some of the later designs of apparatus,
although they will deal with the theory of dark-
ground illumination in general.
The most general methods in use are as follows : —
(1) Siedentopf and Zsigmondy's Ultra-microscope,
which, however, is inconvenient in biological
work, although it has been employed at
times.
(2) Sub-stage Dark-ground Illuminators.
The simplest type is the central stop in the
immersion condenser of high N.A., which, however,
is strongly chromatic.
The simpler forms of dark-ground illuminators,
such as the paraboloid of Zeiss and reflecting con-
densers of most optical firms, are primarily designed
for fine dark-ground structural work such as the
observation of bacteria ; but, as mentioned above,
with a bright source of light they render visible
ultra-microscopic particles.
The ultra-condenser of Leitz, designed by Dr.
Jentzsch, and the cardioid condenser of Zeiss, by
Dr. Siedentopf, are both primarily designed for ultra-
microscopic observations, but are not very suitable
for biological work on account of the delicacy of
adjustment required.
In most of the dark-ground illuminators the rays
fall on the cover-slip at such an angle that total
reflection takes place, so that a clear field appears
black. When objects are present they shine out
brightly by the light which they scatter.
In using immersion objectives, special means
must be taken to reduce the aperture — that is, to
cut out the peripheral rays by means of a diaphragm.
Apochromatic objectives always give the best
results, and the illuminators themselves are usually
achromatic.
(3) By stopping the objective.
This method was also devised by Dr. Siedentopf.
A certain circular area of the centre of the front
lens of the objective is blackened at the back. A
condenser of low N.A. is used and stopped down
till the direct cone of light is just blocked by the
blackened area. When objects are introduced into
the field they scatter the light. The method is
chiefly used for thick preparations, but has the
disadvantage of showing strong diffraction rings.
With regard to the illuminant, in most cases the
better the light the better are the results. A Nernst
lamp gives fairly good results with the paraboloid,
for example, but more especially for the dark-ground
structural observations. A small arc lamp is better,
but best of all is strong sunlight directed on to a
large glass globe filled with water, although this light
cannot always be switched on when required !
Such is an indication of the methods employed.
A short list of literature will be given at the end.
The study of living material is usually most instruc-
tive, so that in most cases water has to be used as
the mounting fluid.
A few of the applications of the method in
botanical work will now be shortly described.
Little will be said of the work included in the first
two classes below, as many of the observations are
mostly of interest to the specialist alone. The main
lines of work may be perhaps classified as follows: —
(a) The study of living bacteria, and so on.
(6) The study of moving cilia.
(c) Observations of the living plant cell.
(a) Little will be said here. The method has
been useful in studying bacteria in the living state
generally, especially when one dimension is sub-
microscopic. The presence and movement of the
flagella have also been observed in the living state.
(b) The method greatly facilitates the study of
cilia generally, as these are easier to observe as a
bright line against a dark background than in
direct illumination.
Ulelah has recently published his results of a
series of researches by means of the method ; he
used, in fact, a Zeiss paraboloid. Motile cells from
practically all the great groups were examined —
zoospores of green and brown Algae, spermatozoids
of Bryophyta, and so on, as well as many Flagellata.
The results are, of course, to be appreciated by the
plant physiologist, but generally the work is of
interest in showing that the method is capable of
profitable application in this direction.
(c) It is. however, with regard to the structure of
the plant cell that the most important results have
been obtained.
The method of illumination employed, demon-
strates the presence of structures and particles
which cannot be observed in direct illumination, and
it also renders much more distinct some particles
which on account of their transparency and small
size are very difficult of observation in direct
illumination.
The greatest difficulty to be encountered in the
application of the method to the study of the plant
cell is that of choosing and obtaining suitable
material which can be examined in the living state.
The object must, if possible, be only one cell thick,
which at once precludes the use of masses of tissue,
or sections of tissue generally. The cell walls must
be optically homogeneous, or nearly so, in order to
allow of an illumination of the cell contents, and,
moreover, the outer wall of the cell must be quite
clean. When all these desiderata have been
obtained the cell contents may be quite unsuitable
— for example, a large peripheral chloroplast scatters
most of the light at once, so that no internal cell
structure can be seen.
Objects which may furnish suitable material
are more especially unicellular organisms, such as
unicellular algae, yeasts and so on, filamentous Algae
and Fungi — Spirogyra, Mttcor, flat plates of cells —
tnonostroma, thin leaves, unicellular or seriate plant
hairs, root-hairs, and so on. There is still another
point which rapidly becomes evident when observa-
tion is begun — the cells must not be too small nor the
October, 1913.
KNOWLEDGE.
363
filament too narrow, or the diffraction images of the
edges mask all other effects.
Much of the work in the observation of the living
plant cell has been done by N. Gaidukov (see
his " Dunkelfeldbeleuchtung" reference at end).
A few general examples of some of the best
objects for observation and the appearance they
present may be described, and in many cases the
first appearance is sufficiently surprising. One of
the most suitable objects for observation is the
green alga Spirogyra. A species with fairly thick
filaments and a rather loose spiral chloroplast is best,
but a close spiral does not prevent good observation,
and, in fact, in some cases may be an advantage
(Price, S.R. ; see references below). A single fila-
ment is mounted in water and covered with a thin
cover-slip for observation. Under quite a low power
of the microscope of, say, two hundred diameters in
good illumination a large number of twinkling points
of light with a rapid dancing motion first attract the
attention. These are particles which occur in the
cell sap and may conveniently be referred to as
" sap-particles." They can usually be seen in
illumination under high powers, especially with
the condenser considerably stopped down. Little
attention as yet seems to have been given to these
particles, which are apparently widely distributed in
plant cells. They seem to increase in number with
a lowering of the plant's vitality.
Under high power, say the three-millimetre apo-
chromat of Zeiss, and a six or twelve compensating
ocular, much more can be made out. The chloroplast
is relatively inconspicuous now, and the protoplast,
which lines the wall of the cell and encloses the sap
vacuole, is seen to be full of rapidly oscillating and
moving particles of a minute size, particles which
are not seen in direct illumination. There is some
evidence to show that particles of two orders of
magnitude are present, the smaller particles being
present in the internal and external layers of the
protoplast. On focusing in a lower plane — into the
vacuole — the sap particles can be seen again, and
now they appear rather as minute bubbles of a
refracting liquid of a greater order of magnitude
•than the protoplasmic particles. In a few cases the
nucleus can be seen, appearing almost clear and
suspended by protoplasmic fibrils in which are
moving particles.
The whole appearance is certainly very striking
and animated, and gives rather a new impression of
the great activity of the living cell.
Incidentally, a dead cell shows none of the
protoplasmic movement, and the coagulated proto-
plast has quite a different appearance.
The staminal hairs of Tradescantia have also been
observed by Gaidukov and show somewhat the same
phenomena. The cell wall is finely striated, how-
ever, so that observation is not so easily made.
The circulation and streaming of the protoplasm
can be well seen.
The latter is also particulaily well shown by
certain cells in the leaf of Elodea, the American
, water - weed, so common in our waterways. A
single leaf is removed and mounted in water. The
leaf is only one cell thick at the edge, and, moreover,
the chloroplasts are relatively few in these cells.
At first only the " sap particles" may be seen, but
with careful observation the protoplasm can be
observed filled with minute particles, exhibiting a
rapid oscillating or Brownian movement. As the
leaf warms up the streaming of these particles along
the protoplasmic threads and round the cell is clearly
seen. After a time a well-marked rotation of the
protoplasm is set up, and the minute particles seem
to travel along at a great rate. Subsequently
enough energy seems to be developed to cause the
chloroplasts to move, but these always do so at a
slower rate than the small particles.
Somewhat similar phenomena, . the Brownian
movement of the small particles in the protoplasm,
and so on, have been described for many other
objects ; for example, Mougeotia cells, root-hairs of
mustard, yeast cells, multicellular hairs from the
tomato plant ; but, as would be expected, there are
differences in detail. Yet other cases seem to show
little or no movement of the protoplasmic particles.
The extreme mobility and the great display of
activity in some of these plant cells seem at first
sight rather surprising and rather militate against
some of the older views of the structure of the
protoplasm of the living cell. Although the observa-
tions yet made are comparatively few — too few to
admit of any elaborate theory being postulated — yet
some sort of hypothesis is required to explain these
phenomena, to be used as a basis for further analysis.
The facts as they appear at present seem to agree
quite well with the hypothesis that the protoplasm is
of the nature of a colloid solution, and in view of
recent work on colloids in other directions this view
is considerably strengthened. The particles which
have been described above are held by Gaidukov to
be actual colloid particles, exhibiting the usual
Brownian movement when suspended in fluid. The
death of the cell results in complete cessation of the
movement — the plasma has coagulated. The liquid
watery colloidal solution of the living cell is, in the
language of the colloid chemist, a hydrosol, and the
coagulated mass a hydrogel. The death of the cell
is thus a conversion of hydrosol into hydrogel.
The colloid hypothesis has been further elaborated,
but this is not the place to enter into a general
discussion of its fuller bearings. It may, however,
prove to be a firm stepping-stone leading to a true
basis of many of the phenomena connected with the
living processes of the cell and with the " life " of
the " life-substance " protoplasm.
The account which has been given is necessarily
very superficial and sketchy, but it may in some
degree indicate that the method is really a useful
one, and one of which a good deal may be expected.
The glamour surrounding new methods often results
in a gross over-estimate of their application ; but this
glamour, let us hope, has partially disappeared in
this particular case, although at first it was very
364
KNOWLEDGE.
October, 1913.
decided. Even if it only serves to take us a small
step forward in the comprehension of the life of the
cell, its continued use will be amply justified.
The following short list of references may be
useful to any interested in the subject generally : —
Zeiss. Pamphlets on " Ultra -microscopy " and " Dark-
ground Illumination." Parts 1 to 8.
Leitz. Pamphlet, " Reflecting Condensers."
H. Thirkill. " Ultra-microscopv." Science Progress in
the 20th Century. 1909-10~ Vol. IV. Page 55.
N. Gaidukov. " Dunkelfeldbeleuchtung und Ultramikros-
kopie in der Biologie und in der Medezin." 1910.
G. Fischer, Jena.
A full list of references is given here : —
Ulelah. Biologischea Centralblatt. 1911.
Price, S. K. ''Observations with Dark-ground Illumination
on Plant Cells." Proc. Camb. Phil. Soc. Vol. XVI.
Part VI. Page 481.
Price, S. R. " The Method of Dark-ground Illumination
in Botanical Research. Sci. Prog., Oct., 1913.
Cotton et Mouton. " Les Ultramicroscopes, les Objets
Ultramicroscopiques." Masson et Cie, Paris. (Out
of print).
Barnard, T. E. " Ultramicroscopic Vision." Nature.
Vol. LXXIX. 1909. Page 489,
A SOLAR OBSERVATORY IN NEW ZEALAND.
By MARY PROCTOR.
On April 14th, 1912, I left New York for a lecture-
tour in Australasia, for the purpose of arousing
enthusiasm and raising the necessary funds for the
establishment of a solar physics observatory in
that part of the world. Exactly a year later, on
April 14th, 1913, I met Mr. Thomas Cawthron, a
millionaire, of Nelson, New Zealand, who had read
about my lectures in which I had pointed out the
necessity for such an observatory in the Dominion,
and he generously offered to provide sixty thousand
dollars to build, equip, and endow an observatory
to be erected somewhere in the vicinity of " the
sunny city of Nelson." If Nelson lives up to its
reputation in this respect, the institution could not
be more favourably situated.
The observatory should prove very valuable for
supplying data which will be of great use in
connection with meteorology, weather forecasting,
and other scientific and practical purposes, such as
enabling us to trace the possible connection between
sun-spots and magnetic storms on the sun and
magnetic storms on the earth.
To establish this theory it was necessary that the
sun should be observed continuously throughout the
twenty-four hours, but unfortunately a gap of one
hundred and fifty degrees separated the solar
observatory at Mount Wilson, in Southern California,
and the one at Kodaikanal, in Southern India. The
proposed observatory at Nelson will not only fill in
this gap, completing the chain of such observatories
round the world, but it will be the only station of
this kind south of the Equator. It will also have
the additional advantage of providing a good
observing station during the months while winter
prevails in the northern hemisphere.
Regarding the climatic conditions of Nelson, they
compare most favourably with those of Southern
California. The annual average of direct sunshine
is two thousand five hundred hours, and of rainfall
in inches during the past thirty years is 37 • 88. Praise
of Nelson's climate comes from Professor Archibald,
the well-known expert meteorologist, as follows : —
" I passed through Nelson twenty-two years ago, and
I was impressed by the bright character of the sky."
The universal opinion of that time was that Nelson
was the climatic paradise of New Zealand. Nelson
is a very suitable site for the establishment of a solar
observatory and the study of solar physics. Con-
sidering that we are now finding that there are
oscillations of weather distinctly connected with the
small as well as the larger periods of solar
phenomena, including the magnetism of the sun and
the surface spots, there is little doubt that the pro-
jected observatory at Nelson will materially aid
meteorologists and physicists to solve the remaining
problems which confront us. We shall learn how
our luminary affects the weather and other conditions
of the earth. It will be work, not only valuable to
Nelson and New Zealand, but to the wide world.
It will be distinctly to the honour of New Zealand
to take a prominent part in an investigation which
is daily becoming more and more of world-wide
interest and importance. Work such as will be done
at Nelson will link with similar study by Sir Norman
Lockyer at Cambridge, Professor G. E. Hale at
Mount Wilson, and Mr. John Evershed at
Kodaikanal in Southern India.
The illustrations show the probable site, usually
referred to as the Fringe, situated two thousand five
hundred feet above sea level ; but at the present
moment of writing (May 8th) the matter is awaiting
the decision of an expert on such matters from
England, at the suggestion of Sir Robert S. Ball, of
Cambridge University. About eighteen months ago
he was invited to come to Australasia to lecture for
the purpose of raising funds for the erection of a
solar physics observatory, but owing to his advanced
age and duties as a professor at the University he
was unable to accept. He suggested that I should
come in his place, and the generosity of Mr. Thomas
Cawthron has enabled me to state that my mission
has been accomplished successfully.
[Since the above was written Miss Proctor has
received a letter concerning the serious illness of
Sir Robert Ball. Consequently the matter now
awaits the decision of Professor Newall, to whom
the letter was handed.]
October, 1913
KNOWLEDGE.
365
I
From a phutu^ttipli
FlGUUE 390.
by Tyree, Nelson.
Mr. Thomas Cawthron, who has offered to establish a Solar Observatory near Nelson, New Zealand.
366
KNOWLEDGE.
October, 1913.
Figure 391. One half of a panoramic view of the mountains to the South-East of Nelson, New Zealand. Maungatapu
Mountain on the left is 3312 feet high.
Figure 392. A continuation of the picture seen above. Fringe Hill in the centre is 2580 feet high. On the summit of
one of these mountains the Cawthion Solar Observatory will be placed.
From photographs by Tyree Nelson.
I
THE CHEMISTRY OF THE FOREST.
By P. Q. KEEGAN, LL.D.
By the chemistry of trees is meant the detection by analysis
of such separable and distinctive organic and inorganic bodies
as are incidental to the vital processes thereof, whether these
substances are the direct outcome of the arboreal life energy,
or are merely the by- or waste-products of the spent and
exhausted activities. The tree, indeed, may be regarded as
the outward and visible sign of an inward and wholly
invisible force. The capital force is the one called " vital,"
shrouded in mystery ; but chemical forces, aided in some
cases by physical forces, are created and set a-going thereby,
and are manifested in visible and tangible shape by the
inevitable consequences of a production of principles mostly
not detectable in the animal or mineral kingdom. It must
be admitted, indeed, that several of the most distinctive
constituents of the body of the tree, its stem, leaf, and flower,
are not the results of any chemical processes known to science,
and cannot be artificially reproduced by the most skilful
application of the most modern and approved synthetic
methods and expedients; that is to say, the chemical origin
of what are called the products of vegetable assimilation is a
mystery shrouded beneath the inscrutable veil of forest
secrecy. With regard to the woodland soil, it may be briefly
stated that it contains much humus, i.e., it is highly charged
with organic matter, which is the essential condition of the
life of certain fungi which assimilate the nitrogen and carbon
thereof, and by association with the roots of the tree
(mycorhiza), contribute to supply thereto these necessary
aliments in the form of ammonia and carbon compounds.
The arborescent forms of the forest flora of the British
Islands are not very numerous, but (native and denizen
species included) they are sufficiently varied as respects
chemical interest and instructiveness. For instance, in the
first place, let us study the chemical characteristics of the
Gymnosperms, taking as an example that stately and sombre-
foliaged occupant of sandy wastes and craggy mounds known
as the Scots Pine (Pinus sylvestris). Perhaps heretofore
we have regarded the leaf as the most vigorously active of the
vegetable organs, but here we see that much of the total
energy is assigned to the woody tissues. For it is there that
the resin, so characteristic of the Coniferae, prevails. Some
specially active parent-cells of the heart-wood contain an
opaque plasma which divides again and again, and thus forms
a group of several daughter-cells, which separate internally
(schizogenous), and so leave a hollow space (resin-passage),
wherein there flows the product of their spent and exhausted
activity (deassimilation), viz., volatile oil and resin. Then,
again, the starch and fatty constituents of the wood undergo
curious transformations, or rather alternations. During the
winter there is no starch whatever in the wood, pith, or bark,
the wood at this time bearing much fat-oil which vanishes in
April, leaving only a faint residue thereof during the entire
summer. Likewise the leaves (really twigs) are free from
starch in winter, but about April 1st, whatever the weather
may be, and although the chlorophyll therein is oily and
inactive, these organs are found crammed with starch, i.e., in
circumstances and conditions that in most dicotyledons would
assuredly preclude this effect ; and the quantity of this starch
gradually diminishes, and disappears altogether in mid-
October. Coniferous leaves in their most developed condition
are always poorer in nitrogenous, carbohydrate, and mineral
(ash) constituents than those of deciduous trees, and the ash
is also of a somewhat different composition. Hence we learn
that our arborescent Gymnosperms (pines and firs) are subject
to a fitful periodicity of life-energy interrupted by pretty long
periods of repose akin to hibernation, all preordained and
operative in the first place in the formed leaves, ere the buds
are evolved or the cambium has awakened. A speciality, too,
is the strong accumulation of " dry substance " in the
tissues under the form of resins, waxes, volatile oils, tannins,
tannoids, glucosides, phlobaphenes, and lignin (but not acids),
while, on the other hand, the relative amount of starch, fat-
oil, carotin, chlorophyll, and albuminoids is comparatively
small.
Reviewing now the more familiar field of the Dicotyledons,
and in the first place the various species of Elm (Ulmus
campestris, and so on), we are arrested at once by the
presence of a very troublesome constituent known as
vegetable mucilage. In the cortex, special sacs or canals
evolved from the meristem, and in the leaves cellulose-
encased roundish compartments in the epidermises, petioles,
and nerves contain mucilage in large quantity. It is a
degradation product of cellulose provoked by the great undue
pressure of growth : it swells enormously in water, and has an
acidic function. Some resin occurs in elm bark and wood
parenchyma, but the quantity of tannin is decidedly scanty in
all parts of the tree. The leaves contain much carotin, wax,
albuminoids, and sugars at all times, and their starch-
producing power is extremely vigorous. In fact, the tree
is a very distinctive starch-tree, and it retains most of it in
winter, little or no oil appearing then in the tissues. The
average amount of transpiration is only moderate, its flowers,
fruits, and leaves grow rapidly, but are short-lived, as the lavish
fortification of its bark, leaves, and even fruits, with lime and
silica, attests, and some of its varieties are even capable of
forming a primary persistent periderm, albeit only feebly
suberified.
Passing on now to those nearly allied, closely related
(taxonomically) congeners, the Birch and the Alder, we begin
to realise the supreme value of chemical analysis as applied in
the world of plants. Both are fat-trees, for in winter the
starch vanishes from the pith, wood, and bark, because the
leaves produce little starch, and the general reserve thereof
is feeble and readily exhausted. So far they agree, but in the
Birch the process of deassimilation is not so complete as that
in the Alder. In the Birch it is not pushed much beyond the
production of waxes, resins, and volatile oils, and hence the
tannins, phlobaphenes, pigments, and so on, are comparatively
sparse. Hence in the " queen of the woods " we observe
a silvery-whitish bark, of ghastly aspect by moonlight, con-
taining some twelve per cent, of a white hydrocarbon (betulin),
easily resinifying in the air, but only about five per cent, or
less of tannin, and very little hidden phlobaphene. The
phellogen that works this effect is stimulated to action by the
rapid growth of the very sappy internal tissues. On the other
hand, in Alder bark there is found sometimes as much as
twenty per cent, of a powerfully astringent tannin, together
with some emodin, which is a higher product of deassimilation
again. This tannin penetrates freely into the medullary rays,
parenchyma, and pith of the wood (birch-wood is almost free
from tannin) ; and although it does not conduce much to
lignification, it renders the wood very resistant to the action of
water. Birch leaves produce more starch, cellulose, fibre,
wax, volatile oil, resin, ash, silica, and soluble salts than Alder
leaves do ; but these, on the contrary, contain much more
nitrogenous matters, and more fat-oil, tannin, pigments, acids,
lime, and manganese. Thus we come to perceive that more
fundamental differences exist between these two tenants of the
forest than what a mere recital of the few and slight specific
characters (chaff-like or woody, falling or remaining scales of
the seed-bearing catkin, and so on) would in any way fore-
shadow or prognosticate.
Certain members of the order Cupuliferae must now claim
our attention. As regards the grand old Oak, it may be
asserted that no member of the vegetable kingdom has been
more exhaustively investigated. All that we need state here,
however, is that the amount of starch which it creates and
367
368
KNOWLEDGE.
October, 1913.
stores up in all its organs is considerably larger and more
durable than that of any tree in our sylva. The beautiful
Beech exhibits a distinctive variation in this respect, inasmuch
as even in January and February its wood is very rich both in
oil and starch, every cell in the parenchyma of the outer rings
being full of starch (not the case in most starch-trees), and
this remains up till April, when the wood is still rich in oil (in
fat-trees there is little oil in spring or summer). In the Beech,
too, the wood becomes lignified very slowly ; the quantity of
tannin produced here and elsewhere is relatively small ; it lays
up a store of starch in the inner rings in a rare manner, and
it requires more nitrogen, potash, and lime than many other
trees. " The whole tree " says Wicke, " sticks, so to speak, in
a siliceous coat of mail, the silica forming a thick solid crust
over the whole stem and the young twigs " (the actual white
colour of the bark is, however, due to lichens). The pure ash
of the bark contains up to ninety per cent, carbonate of lime,
indicating an enormous affluence of acids, mainly oxalic. The
chief difference between Beech and Oak, as revealed by the
chemistry of their leaves, is that the latter is more vivacious
than the former : the Oak has much more tannin and
carbohydrates, and its protein falls off in greater amount
towards autumn, at which time also the quantity of silica in
its ash is little over half of what it is in that of the Beech ;
this latter tree, however, evolves more fat-oil, its ripe nut
containing some twenty per cent, thereof, while the acorn
produces only about six per cent, at most. This various
outcome of these two constituents seems referable to the
varying capacity of the two trees to withstand the effects of
external conditions of weather, and so on.
We now approach the Ash (Fraxinus excelsior) with its
smooth bark and knotty protuberances; and it must be
confessed that it is difficult to render full justice to its perfec-
tion of organisation and to its wonderful wealth of chemical
constituents. In fact, we here enter upon a new chapter in
the chemistry of the forest. In 1856 Prince Salm-Horstmar
discovered in the infusion of the bark a peculiar fluorescence,
and in 1857 he isolated and examined the substance causing it
and named it fraxin. Its dilute aqueous solution with a trace
of alkali exhibits by reflected light a strong bluish fluorescence,
due to the absorption of certain rays. It is a colourless
crystalline glucoside perhaps derived from cinnamene. The
tannin of the Ash totally differs from that of any of our native
or denizen trees, the Holly excepted. In fact, it is identical
with the tannin of coffee, and is accompanied by a tannoid
whose dun shades with alkalies produce the blackish Ash
leaves in the fall. Ash leaves, indeed, may be ranged among
the wonders of British botanical chemistry. They rival the
Oak in the manufacture and storage of starch, but far surpass
it as respects carbohydrates, such as mannite, inosite, and
also malic acid, malates, and mineral matters, but have not so
much wax, fat, carotin, tannin, or mucilage. The difference
in this case arises from the nature of the protoplasm, or of its
behaviour. While, on the one hand, the products of assimila-
tion are only somewhat different, on the other hand the
products of deassimilation exhibit a marked variation. Thus,
while the tannin of all the trees hitherto considered contains
what is called a phloroglucin nucleus, that of the Ash has a
quinol nucleus, and, moreover, it is linked on to the derivatives
of a hydrocarbon which indicate that a larger number of
carbon and hydrogen atoms are relinquished on the disrup-
tion of the albuminoid molecule. This means that the pro-
cess of oxidation in this particular direction is carried in the
Ash leaf to a loftier pitch than is the case with regard to the
preceding organisms in our review. The Ash is a tree of
great soil consumption, and its leaves retain their vitality up to
the first frosts, the ash therein amounting to 10-5 per cent, in
dry matter with 45-8 per cent, of lime. Curious how it is
that this tree sucks up no manganese from the soil, while
closely contiguous plants and trees may absorb a great deal.
The lordly Sycamore and some of its allies remain to be
considered. The chemistry here is comparatively simple.
They are all starch trees, but at the same time are rather
oily. Thus there is a lavish plaster of wax on the lower
epidermis of the leaves of a Sycamore. Its bark is very poor
in tannin, and has no resin apparently, but a saponin-like
substance, very much oxalate of calcium, and 9-4 per cent,
of ash are found here. Its vital powers awaken early in the
year, for concurrently with the regeneration of the starch in
spring a quantity of cane-sugar (rising mainly from the roots
or base of the trunk) becomes dissolved in the cell sap, which
thereby gains sufficient tension to bleed out through the bark
if pierced. The adult leaves have no reserve of starch,
having no true chromoplasts, but contain much carotin, wax,
and albuminoids at all times, also a good deal of tannoid and
tannin, only a little sugar or mucilage, but much oxalate of
calcium almost from birth, and 11-2 per cent, of ash, which
even on 8th August yields 14-9 per cent, silica. The fact
that in the leaves the production of starch declines towards
the autumn, while the cellulose does not increase, the
albuminoids and sugars remain uniform till very late, and
there is a heavy fixation of silica and lime in the old tissues,
indicate the rapid growth and early decline of vitality of these
organs. That well-known ally, the Horse Chestnut, exhibits
a similar chemistry, except that its fruit contains starch and
saponin, and its bark yields the brilliantly fluorescing aesculin
discovered by Canzoneri in 1825. The tannin of these
Aceraceae is especially competent to evolve very brilliant
crimson tints, as is seen in the American Maples in Autumn,
but our species, alas ! are precluded from this beauteous
display by reason of the sharp weather fangs that cause a
premature demise of their external tissues.
By way of summary it may be concluded that starch trees
are Elm, Oak, Ash, Sycamore; fat-trees are Birch, Alder,
Linden, Scots Pine, Holly. The richest in starch, but having
less chlorophyll, are Birch, Ash, Elm, Scots Pine, Oak ; poorer
in starch, but having more chlorophyll, are Beech, Sycamore,
Alder, Poplar, Rowan. As to nitrogen the leaves of Alder,
Elm, Beech, Willow, Linden, Sycamore, contain most ; while
those of Oak, Hazel, Poplar, Ash, have less, as against those
of Birch and Scots Pine, which contain the least. Trees rich
in waxy and fatty matters are Scots Pine, Sycamore, Beech,
Alder, Birch ; while Oak, Ash, Elm, Poplar, Holly, produce
one half or less thereof. The greatest proportion of lignin or
crude fibre is found in Scots Pine, Oak, Sycamore, and
rather less in Ash, Elm, Birch, Alder, and Hazel. Alder and
Oak produce the most tannin ; there is much less in Beech,
Elm, and Poplar. The mineral matters of the soil are most
strongly absorbed by Elm, Sycamore, and Ash, while the other
trees flourish with vigour in most cases on a much sparer diet
of that sort.
SAGACITY OF A DOG.
Mr. James Saunders, of Luton, contributes the following to
The Selborne Magazine : —
" There were two terrier dogs, a black smooth-coated one,
and a rather larger white one. The latter was in the water
by his own desire, where he was enjoying himself. The black
one slipped off the stone coping and had an involuntary bath.
He tried to extricate himself by striving with his fore-paws to
gain the top of the coping, but the sides of the lake were so
perpendicular that his hind feet could get no grip. He
partially succeeded several times, but always fell back till he
showed evident signs of distress. In the meantime the white
dog had left the water by the shallow river bed, and at once
went to see what the other dog was doing. He soon realised the
gravity of the situation and tried to grab the black dog by the
neck. In this he failed several times, but at last got some of his
teeth under the other dog's collar and hauled him out instantly."
COSMOLOGICAL HYPOTHESES.
By R. T. A. INNES.
The best known and still the most widely accepted
cosmological theory is Laplace's nebular hypothesis.
This hypothesis was only put forward in a tentative
manner by its author, although on several occasions
he recurred to the subject. It is proper to note that
although it is doubtful if anyone had ever a greater
facility for clothing his ideas in mathematical
formulas, Laplace used none in explaining the
nebular hypothesis. Many cosmogonies have been
based on ideas not essentially different from
Laplace's — that is, the condensation of a primitive
nebula into rings, which later disrupt into planets,
whilst the central and final condensation forms the
central body or sun of the system. The fission
theory of the formation of satellites and double stars
from condensing bodies is closely connected with
the nebular hypothesis.
Other sets of cosmogonies are indicated under the
meteoric or planetesimal hypothesis, and capture
theory. Kant's cosmogony was more general in
that he postulated neither nebulous matter nor
meteors — merely matter. The nebular hypothesis of
Laplace, and its modifications by Faye, du Ligondes,
Darwin, See, and others, seized on the popular mind
because it was not in too marked discord with the
theological teachings of the age, " the earth was
without form, and void." Genesis i, 2.
By the very mode of its existence the human race
can view but a small part of the drama of nature.
On the surface of the earth, thanks mainly to the
geological record, the mode of the evolution of flora
and fauna and the making of rocks is fairly clear.
But when we view not the surface of the earth, but
bodies outside the earth, the planets, stars and
nebulae, our interpretation is not so easy. We
cannot even say if the sun, and with it the earth,
is growing hotter or colder. We imagine the
rhythm of the universe is periodic, but until one
period is completed — and this the human race
cannot live to see — how can we tell, nay, even guess,
the nature of its periodicity ! The periodicity may
be complicated, is almost certainly more complicated
than that of a butterfly which goes through the
stages, egg, caterpillar, chrysalis, butterfly, and so
on, and what being could by the closest inspection
of, say, a millionth of any one of the sub-periods, egg,
caterpillar, chrysalis, or butterfly, foretell the other
sub-periods ! It is probably thus when we attempt
to explain the evolution of the stars. When Laplace
wrote his nebular hypothesis facts were few, the
laws of thermodynamics had not even been formu-
lated, and modern chemistry was in its infancy.
Hypotheses without facts are not uncommon ; the
Greek geniuses loved hypotheses, but seemed to dis-
dain facts, and the effects of their examples are
buried deep in the fibres of our mentality. The
fundamental assumption of the nebular hypothesis
is that a nebula can condense, not only get more
dense, but even ultimately form liquids and solids of
various atomic weights. This assumption has no
foundation in nature, and is so improbable that it
should not be accepted without proof. Lockyer's
meteoric hypothesis started with a swarm of solid
bodies, meteorites, which by their collisions gave
rise to a nebula, which then followed the Laplacian
theory ; but the spectroscopic evidence on which it
rested has since been proved to be devoid of
foundation.
Although many cosmological hypotheses have
been imagined, I wish to show that another can be
added to them ; its only merit is that it takes into
account the few facts of observation which are
available to-day. The hypothesis is compounded of
the planetesimal hypothesis of Chamberlin and
Moulton, and the radiation theory of Arrhenius,
with the addition of an explosive element suggested
by the mutations of uranium radium-helium.
The primordial stuff out of which the universe is
made is in the form of meteors. Aggregations of
meteors are caused by collisions and gravitation.
These aggregations increase in size forming, firstly,
. cometary bodies ; secondly, planetary bodies ;
thirdly, sun-type bodies. Growth is continuous in
one direction in all these bodies, so that a cometary
body by the addition of more meteorites can pass
into a planetary body, and a planetary body similarly
into a sun-type body, but a sun-type body cannot
increase in size indefinitely, as a time comes when it
will disrupt with explosive force. A cometary body
is a loose aggregation of meteors. A planetary body
is a solid body in which the forces of solidification
and cohesion are at a maximum. A sun-type body
is a liquid body, of which the sun is a prototype.
The reverse process cannot take place; thus a sun-
type body cannot shed meteorites and so lose matter
that it becomes a planetary body, and so on. Under
certain circumstances, such as the near presence of
a large mass, a cometary aggregation can, however,
be dissipated, but this is an indirect effect which
does not concern us here. All three classes of
bodies can radiate substance in the form of
electrons, although at vastly different rates, so that
they can pass from the solid or liquid state to the
gaseous state, which is and will be called here the
stellar state, and from the gaseous or stellar state to
the final form, the nebulous state. The stellar state
is the first step in the degradation of atomic matter.
It has to be considered how this hypothesis fits
A paper Vead to the Science Congress, Lourenco Marques.
369
370
KNOWLEDGE.
October, 1913.
facts. Clausius has taught us that the end of the
universe as an abode of life or available energy will
be reached when entropy becomes a maximum, and
that it does tend to such a maximum. This con-
clusion is not contradicted, it is only enlarged so as
to include in the available energy the enormous
stores of power contained in every atom. The end
of the universe, or at least one sub-period of it, is
reached when every atom has disintegrated into its
component parts, be they electrons or the elusive
nebulium of which nebulae are mainly composed.
The older cosmogonists started with nebulium,
which in some way could condense into atoms and
end with vast cold stars consisting of heterogeneous
collections of atoms containing enormous stores of
unavailable energy. The present hypothesis reverses
the process. We know there are meteorites —
numbers flash through our atmosphere and are seen
on every clear dark night ; a few reach the surface of
the earth. Examination and analysis of the meteors
which have been found show that in the main these
bodies contain all the elements found upon the
earth, and that they are compact bodies formed
under considerable pressure. How they came into
being is quite unknown ; to us they must represent
an earlier stage or sub-period of the universe akin to
the egg or chrysalis stage in the butterfly's period of
existence. The earth is increasing its mass by these
falls of meteorites, but the increase although
constantly in action is very slow. But it is
improbable that the planets of the solar system were
formed by this process ; it is possible that the
planets grow by accretion, but their formation was
due to explosions of the central mass. As long as
matter was considered to be inert, there was no
limit to the quantity of it which could be assembled
in one mass and held together by the power of the
mutual gravitation of its parts. But it is obvious on
further thought that a time will come when the
gravitational pressure of a mass will break into the
atomic structure of its matter and cause explosions.
It is by such explosions that planets are thrown off.
We can imagine that in the solar system one great
explosion threw off all the planets and their satellites,
and that some of the satellites are due to sub-
explosions at the same epoch, and some due to
capture of remnants. In this, the solar-type of
explosion, but one seven hundred and thirtieth part
of the solar mass was thrown off, but we may
expect all types of explosions — thus the original
mass might explode into two nearly equal parts,
examples of which we see in many double-star
systems, or the explosion might be so shattering that
the original mass is almost uniformly broken into
thousands of fragments forming a star-cluster like
w Centauri or £ Toucani. Or the mass of a system
may so nearly balance the explosive force that
explosions are muffled and intermittent ; these
would give rise to stellar-variability or, in the case of
a body like the Sun, act as one of the causes of
sunspots. It has been shown that some of the
transformations of radium are rhythmic, a fact which
suggests that the sunspot period may be due to
atomic disintegration.
Here we may remark that it is not impossible
that explosive action on the Earth, as shown in
volcanic action, is due to the liberation of atomic
energy ; formerly it was ascribed to the percolation
of water into hot strata, but the recent researches of
A. Brun have proved that the ejecta of volcanoes
are free from either steam or water. A time comes
when the central mass of a system becomes fairly
quiescent, such as the Sun now is. In this quiescent
stage the Sun is a globe of liquid with an enormous
radiation of heat and light waves, and emitting
electrons ; its heat is mainly due to atomic disin-
tegration which will continue as long as any of it
remains, or, in other words, as long as it contains
atoms of more than gaseous atomic weight. Its end
will be approached by its passing into a gaseous or
stellar state, which will later devolve into a nebula.
There are no dark suns or stars. Continuity requires
that the Earth and other planets should be going
through a like process, but on a much slower scale
owing to their smaller masses, and perhaps, also, to
the different proportions of the elements of which
their chemical constitutions are built up ; one can
imagine that whilst, say, Jupiter is still growing by
planetesimal accretion, the Sun's attractive mass may
become so small through the emission of electrons
that the centre of our system will be transferred, in
the course of ages, to the planet Jupiter.
The explosion hypothesis suggests an explanation
for the phenomena exhibited by the so-called Novae
or new stars ; these are small stars which almost
instantly increase enormously in luminosity and
slowly and somewhat irregularly fade away, often to
small nebulae. These may be assumed to be gaseous
stars, in which the ratio of their specific heats exceeds
one and one-third ; they are then essentially unstable,
and a time comes when a radical change of state
occurs — a sudden blaze up, followed in most cases
by a rapid disintegration into the final state of
nebulosity, in which entropy has become a maximum
and atomic energy a minimum.
The implication of this hypothesis in the glacial
epochs of the Earth is simple. A glacial period
will come on slowly as the heat of the Sun falls
through the rhythmic close of a period of chemical
disintegration ; the hot period will come on suddenly
with a prodigious melting of the waters, a time of
maximum temperature following the epoch of
greatest cold comparatively closely. If temperature
and time were plotted the curve would resemble
that of the light of a variable star, as it should,
because the cause at work is the same.
If we seem to live in an age of uniformity in
temperature conditions, it is perhaps because the
race can only flourish under such circumstances ; the
theory gives no promise of continued uniformity.
An explosive disintegration of atomic energy on the
Sun may occur at any time. We can only surmise
from past conditions on the Earth that at present
the Sun is getting colder in preparation or as an
October. 1913.
KNOWLEDGE.
371
antecedent to a further outburst. Here again the
behaviour of variable stars is an indication ; although
some of these stars are remarkably regular in their
changes, others are not, and generally the fainter the
minimum the more rapid and brighter the following
maximum.
In building up the above hypothesis the follow-
ing facts of observation have been borne in mind : —
1. The mutation of heavy elements, such as
uranium (atomic weight 238-5) into
helium (atomic weight 4) with an enormous
liberation of energy spread over thousands
of millions of years.
2. The changing of stars into nebulae of which
some four or five cases are known, whereas
the reverse process is unknown.
3. Gaseous stars (spectra showing helium and
hydrogen, with or without bright lines) are
very light, their density not exceeding one-
ninth that of the Sun, whilst their gravitative
power seems to be " nil." Thus the brilliant
close pair a Crucis shows no orbital motion,
whilst the essentially wider solar-type star
a Centauri is a rapid binary pair. (N.B.
— -Wider is used in a mathematical sense
and includes the effect of surface luminosity ;
so far as distance alone goes, a Centauri
is not so wide as a Crucis.)
4. Nebulous matter is found near most stars of
the gaseous types — thus the nebulous regions
of Orion are in the midst of helium-type
stars ; nebulous matter is unknown near
solar-type stars.
As, under the explosion hypothesis, the Sun is
liquid it cannot maintain its temperature by con-
traction, because liquids are virtually incompressible,
hence Helmholz's theory of the maintenance of solar
heat is not applicable. It is further improbable that
gaseous or stellar-type masses always contract as
they radiate heat ; on the contrary, Kelvin's investi-
gations indicate very strongly that such masses of
gas may expand. The argument that spiral nebulae
are systems in formation, overlooks the palpable fact
that these objects are exceedingly faint. Long
exposure photographs give very misleading pictures
of spiral nebulae. In nearly every case the total
brightness is less than any one of its neighbouring
small stars. It would be of the same order of
reasoning to assert that islands are formed out of
wisps of cirrus cloud.
The commonly received view that gaseous stars
are hotter than liquid or sun-type stars has perhaps
been engendered by the classification really based
on the nebular hypothesis, viz., that white stars are
the hottest and that sun-type stars already show
signs of cooling, but Huggins clearly shows that
solar-type stars are the hotter — thus in his " Atlas
of Spectra," 1899, page 85, he says: —
" In strong contrast with this falling off in Vega
at about X 3,700 the continuous spectrum of the
solar stars, Procyon and notably Capella — that is to
say, the narrow bright intervals between the
numerous strong dark lines, ... is obviously
far more intense." And it may fairly be asked, if
the gaseous or stellar type of star is the hotter, why
it should not show metallic lines in its spectrum.
The answer, under the new hypothesis, is that such
stars no longer contain substances of high atomic
weight, as these substances have disintegrated into
the simpler gaseous elements.
One cannot imagine the process, in a universe
tending to uniformity and to a maximum of entropy,
by which a simple gas, such as nebulium is, can be
transformed into complex atoms containing enormous
stores of energy. The reverse process seems to be a
more fitting one ; it starts with heterogeneity and
finishes with homogeneity. In short, Laplace's
nebular hypothesis as a representation of nature is
quite untenable, as it is contrary to observation and
to known chemical and thermodynamical laws ; in
spite of this, literally volumes of mathematical
deductions (but not by its author) have been drawn
from it.
I have added a list of references to various
modern authorities whose views have influenced
my own ; some numerical results have been quoted.
References.
Barnard. — "The Temporary Stars. On the present
appearance of some of these bodies." Astro-
nomische Nachrichten No. 4655, 1913, May
20th.
Nova Cygni, 1876 : Its appearance is distinctly
hazy.
Nova Aurigae, 1891 : Its image is ill-defined.
Nova Sagittarii, 1898 : It is always hazy and
ill-defined.
Nova Lacertae, 1910 : It presented the appearance
of a very small nebula, less than 2-in. in diameter, of
a bluish-white colour.
Chamberlin, Moulton and others. "Contributions
to Cosmogony and the Fundamental Problems of
Geodesy." " The Tidal and Other Problems,"
1909.
This is a remarkable work, which is published
under cost price by the Carnegie Institution of
Washington, but it is so poorly advertised that its
circulation is far below its real merits. For this
reason, I venture to quote some of the conclusions
reached in it.
Chamberlin: — "The application of the most
radical and the most rigorous method of estimating
the f rictional value of the present water-tides . . .
seems to show that they have only a negligible
influence on the Earth's rotation . . . The tides
of the lithosphere are chiefly elastic strains, and have
little retardative value . . . The accelerative
forces seem to be also negligible . . . There
has been no such change in the rate of the Earth's
rotation ... as to require to be seriously
considered in the study of the Earth's deformations."
(Page 59). J j xa
Chamberlin writes (page 23) : — " There can be no
372
KNOWLEDGE.
October, 1913.
theoretical doubt that there are tides of the litho-
sphere."
Since then Professor A. Young's discovery of lunar-
tide effects on the Karoo has since been published.
(" Tidal Phenomena at Inland Boreholes near
Cradock," Trans. Roy. Soc. of South Africa. 1913,
Vol. Ill, Part I.)
Moulton : — " In a word, the quantitative results
obtained in this paper are on the whole strongly
adverse to the theory that the Earth and Moon have
developed by fission from an original mass, and that
tidal friction has been an important factor in their
evolution. Indeed, they are so uniformly contra-
dictory to its implications as to bring it into serious
question, if not to compel us to cease to consider it
as even a possibility." (Page 133.)
"... The hypothesis of Laplace has the
support of no observational evidence. On the
contrary, there are well-known considerations . . .
which compel us to reject it . . ." (page 137).
As to the possibility of the fission-theory of the
formation of satellites, planets and double-stars,
Moulton's conclusions are : —
"(1) We find that the Sun cannot arrive at this
critical stage (fission) until its mean density shall
have exceeded 307 x 1011 on the water standard.
This corresponds to an equatorial diameter of the Sun
of about twenty-two miles.
(2) We find that the Sun cannot become so oblate
as Saturn is now until its mean density shall have
exceeded 148 x 1010 on the water standard. . . .
Since even the latter density is impossibly great we
conclude that the Sun will never become so oblate
as Saturn is now, and that it will always be more
stable than Saturn is now.
"(3) We find that Saturn cannot arrive at the
critical state at which Jacobian ellipsoids branch
until its mean density shall have become twenty-one
times that of water. . . We conclude because of the
great density demanded that Saturn will never suffer
fission." (Page 159.) " Perhaps the hypothesis that
stars are simply condensed nebulae, which has been
stimulated by a century of belief in the Laplacian
theory, should now be accepted with greater reserve
than formerly. Up to the present we have made it
the basis not only for work in dynamical cosmogony,
but also in classifying the stars. It may be the
time is ripe for a serious attempt to see if the
opposite hypothesis of the disintegration of matter —
because of the enormous sub-atomic energies, which
perhaps are released in the extremes of temperature
and pressure existing in the interior of suns, and of its
dispersion in space along coronal streamers or other-
wise— cannot be made to satisfy equally well-known
phenomena. The existence of such a definitely
formulated hypothesis would have a very salutary
effect in the interpretation of the results of astrono-
mical observations. We should then more readily
reach what is probably a more nearly correct
conclusion, viz., that both aggregation and dispersion
of matter under certain conditions are important
modes of evolution, and that possibly together they
lead in some way to approximate cycles of an extent in
time and space so far not contemplated." (Page 160.)
Lunn. — "Geophysical Theory Under the Planetesi-
mal Hypothesis."
In this paper, if I grasp aright the meaning, the
author shows, by adopting plausible laws of com-
pression and density, that it is only small bodies that
can be very dense, which is borne out so far as they
go by astronomical observations ; thus we have
Type.
Body.
Mass.
Density.
Planetary
Meteorite ...
Infinitesimal
3 to 8
,, ...
Mercurv ...
1/5000000
1-21
„
Earth
1/330000
1-00
Sun or Solar...
Sun
1
0-26
Stellar or
Gaseous...
Algol*
3
0-14
») i»
ft Lyrae
9-6
0-00016
* Uncertain, Stebbins gives Mass 0-55, Density 00.2.
Cox.—" Beyond the Atom," 1913.
" One pound of the emanation would, at its
maximum intensity, radiate energy at the rate of
about ten thousand horse - power. This large
emission of energy from the radio-active bodies
throws an interesting light on two questions which
have long been the subject of controversy, the age
of the Earth and the source of the heat of the Sun."
(Page 109.)
Period of fall of Uranium to half-value six
thousand million years. (Table, p. 91.)
Kelvin (and Green). — " The Problem of a Spherical
Gaseous Nebula." Trans. R. S. of Bdin., 1907- 8.
" It is scarcely possible to conceive that any fluid
composed of the chemical elements known to us,
could be gaseous in the Sun's atmosphere at depths
exceeding one hundred kilometres." (Page 268.)
Kelvin calls a gas in which a the ratio of the
specific heats is greater than 1$ a gas of species P ;
and it is almost certain that all monatomic gases
have a = If.
" We see that the central temperature of a globe
of gas P in equilibrium increases through gradual
loss of heat by radiation into space. We then see
also that the internal energy of a globe of gas P,
continuing in a condition of approximate equilibrium
while heat is being radiated away across its boundary,
would go on increasing, and the work done by
mutual gravitation of its parts would go on increas-
ing till the gas in the central regions becomes too
dense to obey Boyle's Law." (Page 281.)
In this statement no account is taken of any
possible liberation of atomic energy, but, even with-
out this, it is evident that the underlying idea of
contraction is at fault, and that a decrease of
internal temperature and increase of size could go on
together. So far as observation goes, the evidence
is in favour of the latter view. Although hardly
supplying an exact parallel, it is well known that the
gaseous envelopes of comets contract as they
approach the Sun,
October. 1913.
KNOWLEDGE.
373
Newcomb. — " The Stars : A Study of the Universe."
1902.
" A very remarkable case is that of Zeta Orionis.
It has a minute companion at a distance of 2" -5.
Were it a model of the Sun, a companion at this
apparent distance should perform its revolution in
fourteen years, But, as a matter of fact, the motion
is so slow that even now, after fifty years of observa-
tion, it cannot be determined with any precision.
It is probably less than 0"- 1 in a year. The number
expressing the comparison of the density and surface
brilliancy of this star with those of the Sun is
probably less than 0-0001. The general conclusion
to be drawn is obvious. The stars in general are not
models of our Sun." (Page 200.)
Newcomb. — " Popular Astronomy," 1882.
" Then a mathematical computation of the attrac-
tive power exerted by such a system of masses
(five hundred million sun-masses) shows that a body
falling from an infinite distance to the centre of the
system would acquire a velocity of twenty-five miles
a second." (Page 501.)
This calculation does not seem to be correct, but
it serves to show how impossible it is for the potential
energy of a nebula composed of nebulium, helium
and hydrogen to be changed by gravitation into the
radio-active and other atomic energies of heavy
atoms. The velocity with which a small mass
falling from rest at an infinite distance would strike
the Sun is three hundred and eighty miles a second.
This means that a gram falling into the Sun would
generate forty-four thousand eight hundred and
forty-four calories ; this is but one five hundred
thousandth of that evolved by radium.
Perry.— "The Life of a Star." Nature, 1899,
July 13th.
"Assumptions like those of Homar Lane and
Ritter may lead to results which are altogether
wrong. . . . Homar Lane, Lord Kelvin, Ritter,
and all people who have tried to make exact calcula-
tions, have assumed that the stuff of which a star is
composed behaves as a perfect gas in a state of
convective equilibrum. . . . But if we apply
our results to the Sun we find that at its centre there
is a density thirty-three, that is, fifty per cent,
greater than the ordinary density of platinum. It
seems to me that speculation on this basis of
perfectly gaseous stuff ought to cease when the
density of the gas at the centre of the star
approaches 0.1 or one-tenth of the density of
ordinary water in the laboratory. . . It seems to
me that if a mass of this kind of gas (in which H the
ratio of its specific heats =1§) gravitates by itself
from an infinite distance, it retains all its energy.
But such gas must surely be imagined to be radiating
heat, as it is not at zero temperature. Where can it
get such heat ? I come to the conclusion that there
must be atomic energy available somehow in it.
I say that no substance for which 8 =1$ can behave
as a perfect gas."
Kelvin's remarks on and his endorsement of
Professor Perry's conclusions will be found in
Nature, 1907, February 14th.
Ramsay. " Elements and Electrons, 1912."
" Cordite, the explosive powder used for our
artillery, evolves 1,253 calories per gram. . .
Radium, 2,800,000,000 calories."
CORRESPONDENCE.
"THE ORIGIN OF LIFE."
To the Editors of " Knowledge."
Sirs, — I have seen Mr. H. Stanley Redgrove's article in the
August number of " Knowledge " in which he refers to a
"nine days' wonder" produced by my experiments on the
action of radium salts on sterilised organic media, such as
gelatin bouillon used for the cultivation of bacteria. He adds
that Mr. Soddy showed the effects were of a purely chemical
nature. I was not aware that Mr. Soddy had made any
experiments upon the subject ; nor do I believe that unlike the
effects produced by barium, strontium, and lead salts, the
results due to radium are of a purely chemical nature.
The effects are on the whole physical rather than chemical
as I have repeatedly pointed out, and as Sir William Ramsay
was good enough to explain they might have been expected to
be. My own views upon the subject were put forward at
length in my article in the Fortnightly Review, September,
1905, and in my book on the "Origin of Life" published in
1906, of both of which Mr. Redgrove is apparently unaware. If
these experiments remain a nine years' wonder I throe not, but
I venture to deny, considering the prolonged discussion to
which they have given rise, and are likely yet to give rise to when
more fully understood, that they were a nine days' wonder if
indeed they can be said to be a wonder at all.
BRITISH MEASURES NEARLY HYDROMETRIC.
To the Editors of " Knowledge."
Sirs, — It is not, perhaps, generally known that our British
system of weights and measures is very nearly hydrometric,
that is, having a simple relation between the measures of
length and weight through the medium of water. If we
suppose that the gallon is reduced by the small amount of
three one-thousandth parts, we have the following interesting
and useful relation :
Sixty-four cubic feet = four hundred gallons.
We may visualise this by picturing a cube which measures
four feet in each direction and therefore contains 4X4X4, or
sixty-four cubic feet.
Now by law a gallon of water weighs ten pounds; and to
preserve this relation we must suppose the pound to be
reduced by the same small amount as the gallon. If this be
done, and if for convenience we call our four-foot cube a
" vol," we shall have
One vol of water weighs two tons (four thousand pounds).
An easy deduction from this is
One cubic foot of water weighs one thousand ounces
and from this again we have
Tn-foot cube of water weighs one ounce.
IMMO S. ALLEN.
Weybridge.
JOHN BUTLER BURKE.
London Institution,
Finsbury Circus, E.C.
THE HISTORICAL MEDICAL MUSEUM.
In our notices in the August number of
" Knowledge " allusion was made to the Historical
Medical Museum, organised by Mr. Henry S.
Wellcome, and formally opened by Dr. Norman
Moore, the President of the Section of the Interna-
tional Medical Congress which dealt with the history
of medicine. The idea of forming a museum illus-
trating the history of the healing art occurred to
Mr. Henry S. Wellcome several years ago, and
the remarkable collection of rare and curious objects
of historical interest connected with surgery,
medicine, and the allied sciences brought together
from all parts of the world is now housed at 54a,
Wigmore Street, London.
Dr. Norman Moore in the course of his opening
address said that the Museum, which had been
recognised as a part of the History of Medicine
Section of the International Medical Congress,
formed a most important addition to its studies.
He reviewed the formation of earlier museums, all
of which are relatively recent creations and usually
developments from libraries. In the reign of
Elizabeth, John Dee formed one of the first, a
collection of mathematical and astronomical instru-
ments and of various curiosities in his library at
Mortlake, but the first considerable museum in
England was that of John Tradescant, father and
son, at Lambeth. The catalogue of the Trade-
scantian Museum was printed in 1656, and shows
that it had fifteen sections, among which were
beasts, birds, reptiles, weapons, and man)- dried
plants and fruits ; for the Tradescants were primarily
gardeners and collectors of herbs. Their museum
went to Elias Ashmole, and was re-arranged at
Oxford, where most people have seen the unique
head and foot of the dodo, the body having been
destroyed in one of those periods of darkness to
which all universities are liable.
Another great museum was formed in London by
James Petiver, an apothecary to the Charterhouse,
who was educated at Rugby School and at St.
Bartholomew's Hospital. He was a botanist and
entomologist, but the many sea captains whom he
came to know, brought him every kind of curiosity
from all over the world. Sir Hans Sloane bought
his collection and others, made a great one of his
own, and bequeathed the whole to the nation.
All these early museums were associated with
libraries and contained every kind of specimen, and
this form the British Museum still retains. The
museum of Francis Calceolari, of Verona, is described
in a folio of eight hundred pages printed in 1622,
and a picture of the museum showed the original
form which developed into such a collection as is the
British Museum. The specimens were in a well-
proportioned room, paved with variegated marble
and surrounded by an ornate sort of dresser with
drawers and shelves. At one end were books and
on the shelves all round were specimens. On one
side was a statue of Atlas bearing the world, showing
the regions whence the specimens had come, and on
the other Minerva, showing that all learning was
included in the collection.
The gift of Dr. William Hunter to the University
of Glasgow was another museum of this type. It
contains pathological, anatomical, and natural history
specimens, manuscripts, pictures, early printed books,
Greek and other coins.
A more limited kind of museum succeeded these
vast collections, of which a type is the collection of
anatomical preparations formed by Edmund King,
surgeon to St. Bartholomew's, in the seventeenth
century. Of these specialised museums the greatest
was that of John Hunter, now under the care of the
Royal College of Surgeons in Lincoln's Inn Fields.
The museum, which they were there to open
was the first established in England to illustrate
the history of medicine, and it might justly be
regarded as a further step in the establishment of
the subject as a regular study.
The origins of medicine might be studied in two
directions. In the hall in which they were
assembled could be seen two figures which typify
these. There was Ixtilton, the Mexican god of
healing, his head covered by a grotesque mask, a
necklace of the teeth of the sperm whale round his
neck, a curious instrument of enchantment in his
right hand, seeming to have uttered some strange
and terrifying ejaculation as he extended his left
hand. Near him was the Apollo Belvedere, the
most perfect of the sculptured representations of
men ; his face showed, the highest flights of
thought and powers of observation. The figure of
Ixtilton suggested charms, amulets, and magical
ceremonies. The figures of Apollo and of his son
Asklepios suggested observation, experiment, and
reasoning.
It is always useful when considering the develop-
ment of any phase of human activity which began
at a time before written records were made, to study
what is done at the present day by uncivilised people,
and one section of the Historical Medical Museum
is devoted to what one might call superstitious
medicine, to the fancies and fetishes of savages and
the ways and implements of witch doctors. For
instance, in the entrance hall we find one of the
rough figures from the outside of a village, into
which scores of sufferers have driven spikes and
nails, indicating the places in which they felt pain
374
October, 1913.
KNOWLEDGE.
375
sk & '•
m; .y ~^
' 4ljfr = _ MrfJf "
•
fl^C
^^ffl^^^MPW
^R^ra
10 1
PI
«* *
U
IP
1 1
RJ ^^^^
™ \1
M* U\
^K^m ^H
i
±U
■»■ ' jj
Figure 393. The Barber Surgeon's Shop.
Figure 394. A Roman Surgery in Pompeii.
376
KNOWLEDGE.
October, 1913.
Figure 395. Liebig's Laboratory.
Figure 396. An Alchemist's Laboratory.
October, 1913.
KNOWLEDGE.
377
in their own bodies, and with the belief that by the
simple process adopted they would be cured.
Adjacent to this exhibit, and coming like it from
tropical countries, we have quite the latest develop-
ment of modern zoological medicine ; for arranged
under microscopes are slides illustrating the most
important Protozoa which cause disease, and on the
walls are maps, diagrams, and pictures showing the
past history and present knowledge of malaria, yellow
fever, sleeping-sickness, and other diseases which
make themselves felt in hot climates.
Exceedingly interesting is the series of portraits
and relics of Dr. Edward Jenner, the discoverer of
vaccination, which are in an alcove of the Gallery of
Pictures, and, indeed, not the least remarkable part
of the collection is that devoted to celebrated
medical men.
Returning to the bacteriological side we are
reminded again and again of the great benefits of
antiseptic surgery. At the same time there are
many pictures of operations performed in ancient
days which proved perfectly successful. In this
connection it may be mentioned that not a few of
the exhibits indicate what operations were like before
the introduction of anaesthetics. One peculiar
feature of the representations, whether they be of
operations, of post mortems, or of birth chambers,
is the large audience that has collected together in
most of the cases.
As may be expected, a fair amount of space is
devoted to surgical instruments and their evolution,
but it must not be thought that there is not an
immense amount of material of general interest.
There is an excellent selection of charms and
talismans, including many Egyptian amulets, and
a feature which we have chosen to illustrate here
by the courtesy of the Museum Committee is
the reconstruction of ancient shops and labora-
tories. On page 375 we show the barber surgeon's
shop, the ceiling of which is decorated with bleeding-
dishes. Below, on the same page, we reproduce a
photograph of a Roman surgery in Pompeii, which
has been reconstructed for the Historical Medical
Museum, and the furniture and decoration of which
have been copied from the originals found in
Pompeii and Herculaneum. On page 376 is
depicted Liebig's laboratory, and also that of an
alchemist.
Other points of special interest on the ground
floor are the representation of a lying-in room of
the sixteenth century, the chapel showing votive
tablets, chiefly from Perugia, which were offerings
put up out of gratitude by those who had recovered
from accidents or disease during the seventeenth,
eighteenth, and nineteenth centuries. We must not
forget to mention also a London pharmacy of the
eighteenth century. The shop front is the original
of that established in 1798 by John Hell, the founder
of the Pharmaceutical Society. The room at the
back contains the actual fittings from a pharma-
ceutical laboratory of the eighteenth century which
once stood in Russell Street, Covent Garden.
It would be impossible within the limits of a single
article to give a really comprehensive account of all
that Mr. Henry S. Wellcome and his able assistant,
Mr. C. S. Thompson, have got together, but we may
mention a few things which have attracted our
attention during our visits to which allusion has not
yet been made.
Among the very many pictures are representations
of Ambroise Pare using the ligature when amputat-
ing on the battlefield at the siege of Baravilliers in
1552 ; of William Gilbert demonstrating the magnet
before Queen Elizabeth ; of William Harvey
explaining his theory of the circulation of the blood
to Charles I ; and of Leeuwenhoek with his micro-
scope. Elsewhere there is a fine collection of early
microscopes, which alone would be worth a visit to
the Museum.
A case not mentioned in the catalogue contains
the shirt, drawers, and garters worn by Charles I on
the scaffold, together with touch-pieces, mostly
nobles from the reign of Henry VIII onwards, used
in connection with touching for king's evil.
The frieze in the gallery of pictures represents the
sculptured reliefs in the birth-house at Luxor
illustrating the birth of Amenophis III, 1450 B.C.
In the gallery devoted to books, manuscripts, and
diplomas we find a demand from the Rector and
Council of the University of Pavia to the Inquisitor
of Witches. It appears that the anatomical depart-
ment of the University was entitled to the body of
one malefactor every year, but that they had not had
one for six years; and hearing that a woman had
been sentenced to be burned alive for witchcraft, the
authorities applied to the Inquisitor, requesting him
to choose some other method of killing her, so that
her body might be useful, not only to the University
of Pavia, but to the world at large.
We are shown also the contents of the opium den
raided in the east end of London which previously
had furnished Charles Dickens with his references
to opium smoking in " The Mystery of Edwin
Drood." The evolution of the infant's feeding bottle
from a cow's horn is illustrated, and there are some
interesting models of and original parturition chairs.
A Sicilian one of the latter, dating from the
eighteenth century, was believed to possess special
powers, and was known as "The Miraculous Chair
of Palermo." It was in the possession of a famous
family of midwives for three generations, and it is
estimated to have been used in two thousand cases.
With the instruments of torture we find a number
of appliances used for restraining the insane from
the fifteenth to the eighteenth century. There are
ancient weights and measures, and a collection of
curious materials used in medicine. It is understood
that the Museum will be made a permanent one, as
a great many of the objects belong to Mr. Wellcome
or have been presented, while a number of those
who have lent specimens will allow them to remain
for some time on exhibition. The Museum is not
open to the public, but members of learned societies
can gain admission.
THE NATURE OF X-RADIATION
By W. F. D. CHAMBERS, B.A. Cantab.,
Barrister -at- Law.
(For Illustrations, see Page 390).
Is the universe a liquid or "flowing crystal" in
process of transformation, with varying acceleration,
to the solid or cubic state ?*
Daring as such a speculation may appear to-day,
its analogies are almost involuntarily suggested by
recent developments in optics and crystallography ;
and speculation (in leisure hours) gives a zest to
science.
Even the older physics and astronomy taught us
that it was not improbable that the sidereal universe
might be tending, under laws of conservation and
dissipation, to a uniform diffusion of heat, a rigor
mortis, in which there should exist no longer the
restless surge of potential differences which is
responsible for the grand drama of life and
evolution.
Coming now to sober facts, it will be familiar to
your readers that the X-rays, hitherto supposed
to be subject neither to refraction, diffraction, nor
deflection by magnetic fields, have at last yielded
to the seductions of crystalline substances, as the
present writer predicted they would four years ago.
From the year 1905 a particulate theory of the
aether, or medium supposed to pervade space, has
been advocated, and it was proposed that light, in
some forms at least, might consist of polar particles,
or self-satisfying doublets, which neutralise inter se
their chemical valencies, and, even in a high degree,
their susceptibility to external stress. The X-rays,
and at first the alpha particle of helium, emitted by
the radium atom undergoing transformation, were
supposed to be among these forms. This hypo-
thesis, first published in The Journal of Downside
College, 1907, was later sketched as a general
theory of Energy-Action in the Scientific Monthly
Magazine. The distinctive geometrical feature of
the attempt was the use of Gregory St. Vincent's
principle of the quadrature of the hyperbola, which
curve in its rectangular form was supposed to furnish
a limit to the excursions of light and cathode
particles, when the curve is transformed to polar
coordinates, and rotation round an axis is supposed
added to the motion. Professor Bickerton, quite
independently of the writer, has made use of a
similar geometric scheme for his Kinetol, vide
" Birth of Worlds and Systems," 1911, page 17.
Benoist [Journal de Physique (3), X, 1901, page
653, and elsewhere] has shown that when X-rays are
allowed to fall upon various metallic surfaces after
passing through a standardising prism of paraffin,
the molecular weights plotted against the absorptions
seem to approximate to such a curve, and this law
of absorption (which must correspond with a redistri-
bution of material particles) is independent of
temperature. Furthermore, there is reason to think
that individual series of compounds are susceptible
of treatment in the same way, especially as regards
their critical changes at high temperatures. We may
also recall the fact that in his original experiments
on the modifications of light produced by narrow
apertures Newton found that the shadows produced
by knife-blades placed in the path, approximated to
rectangular hyperbolas the more nearly the edges
were brought together.
Professor Bragg has given the more complete
expression of the doublet theory of X-radiation, and
Tutton has dealt with the conception in its wider
application in his work on crystals (" International
Science Series "), where he illustrates the various
internal and external forms which may be produced
by " astatic " or moving magnetic fields.
It has also been pointed out that such a theory of
the ultimate significance of Mendeleef's famous
principle of periodicity would probably lead us to
suspect a composite nature of hydrogen, which
might be considered as a primary doublet, or perhaps
connected with the terrestrially unknown gases
coronium and nebulium ; and now Sir J. J.
Thomson has given grounds for believing in the
possibility of some such modification of Prout's
hypothesis. Hydrogen, if not composite, is at least
capable of some extraordinary action with neon.
It must not, however, be supposed that such
speculations are opposed fundamentally to the
undulatory theory of light. The discoveries of
Perrin in connection with, the " Brownian move-
ments " in fluids in no way invalidate tidal theory,
though they tend to show that water may be
considered from another, and perhaps deeper, point
of view than that which treats of the unresolved
motion of its particles, or movements en masse. The
mechanism of ripples or " pulses " in aether may in
like manner be shown to be subject to general laws
of arithmetical and geometrical progression in the
distribution of constituents, and yet this need by no
means change the law of averages, the differential
equations of the group effects. Similarly we assert
nothing of the movements of individual birds in a
flight or of bees in a swarm merely because we see
numbers of them together moving as if they had no
purpose or aim in their random wanderings on
behalf of nest or hive. Indeed there are cases where
:,: Some recent theorists have sought to reduce even colloids to a crystal basis.
378
October, 1913.
KNOWLEDGE.
379
such aggregates of moving individuals, e.g., the spiral
nebulae, will appear perhaps like a stationary or
wavy streak of cloud maintaining a fictitious appear-
ance of rest during long periods ; and yet they are in
all probability the seat of turbulent centrifugal
action the ends of which it will take aeons to
discern.
Professor See, of Mare Island, California, in his
recent monumental work on the nebular theory,
maintains that he has adduced evidence that the
older forms of these mysterious germs of worlds
approximate to the Archimedean form of spiral, the
later tending to the logarithmic. These curves can
express respectively arithmetical and geometrical pro-
gressions such as Perrin found ; and it is noteworthy
that upon any such theory of gravitation, as a
residual mode of energy, as that of Lorentz a resist-
ance varying in the inverse square must be added.
Professor See in a recent letter to the writer
suggests that sufficient attention has not yet been
given to such attempted correlation ; such was also
the opinion of Poincare. It appears not improbable
that free electrons passing through atoms, or some
stars, such as 1830 e Groombridge, through globular
clusters, would do so, not upon long ellipses, but
rather on elliptiform helices, their orbital motion
being gradually damped while passing through the
centre of the cluster. Yet in no science must we be
more vigilant against spurious appearances of
irregularity or regularity than in optics. In that
science a speculative element is positively a saving
grace ; as Faraday expressed it : " That man only
is condemned who cherishes fixity of opinion." Do
not the canals of Mars teach us a like lesson, that these
questions of law or ultimate expressions of fact are
still open to faith in a beneficent and volitional
purpose ?
In pursuance of such ideas Mr. Rankin and the
writer have recently (Nature, June 19th and August
21st, 1913) been able to show that X-rays are
" diffracted," or at least characterised by contact or
close proximity to metals as well as "crystals," and
even by substances such as plate glass (see Figure
411), which must be regarded as either structureless
or at least in a transitional stage, seeing that it is a
super-cooled liquid. Some of these effects have also
been obtained through cast, as well as wrought, iron
plates (up to one centimetre in thickness), used as
obstacles without apertures, showing a geometrical
pattern on special rapid plates which can scarcely
in all cases be attributed to the mechanical rolling
of the metals. It seems not improbable (see Figure
410) that the primary beam of X-rays has under-
gone some displacement or shift, as though it were
subject to some repulsive agency which begins to
act perceptibly at short distances, effects which are
visible only to the photographic eyes of science. In
this experiment a thin lamina of mica was used to
cover the aperture in a lead screen, and was placed
at an angle of 85° to the rays. The curious bands
upon the reflected portion of the beam are still, we
believe, unexplained. A series of upwards of two
hundred experiments has been made with the
object of throwing light upon some of the obscure
questions raised by the recent reflection of X-rays.
A short resume only of the results can be given in
the present article.
Halos, similar to those of Figures 406 and 407,
were obtained both with and without mica, or other
crystal used to cover the apertures, which were
generally about a quarter of an inch in diameter, in
metal screens, lead, iron, brass, and others. One
hypothesis of these halos attributes them to atmo-
spheric secondary radiation. They are probably not
halation effects, though if this were the case it would
be tantamount to a reflection of X-rays from a glass,
i.e., a non-crystalline surface, the back of the
" special rapid " plate. The term " halo " is care-
lessly used by photographers, and should we
think be confined to appearances such as Figure
406, where the feature is independent of the image
of the direct rays ; in Figure 407 the white band
alone secures the effect from being possibly due to
secondary radiations, or some cause not implicating
the primary rays. In experiments (see Figure 409)
to study the disposition of the reflected spots from
mica placed normally to the aperture in an iron
screen it was found in several cases that these
markings occur at increasing distances from the
centre, indicating a spiral sequence ; the exterior
spots not well seen in the reproduction, appear
elongated or drawn out into bands which are not
concentric. Figure 408 shows one arm of a bright
cross which had appeared on one negative where no
mica or crystal had been interposed in the aperture
of an iron screen. This cross covered the whole
plate, i.e., extended beyond, and was apparently
independent of, the image of the aperture, and
suggested a possibility that the primary rays might
possess some structure or be polarised or quenched
in special directions by the use of certain crystals.
But in further experiments black bands parallel and
normal to the arms of a cross were obtained even
with the direct or uninterrupted rays received upon
a plate within a wooden box containing an intensify-
ing screen. This raised the question whether these
bands might not be purely photographic effects due
to some development errors or the mechanical pro-
cess of plate manufacture, though plates of various
makers had been used and all the non-essentials of
the experiment repeatedly changed. A crucial trial
was therefore devised to determine how far photo-
graphic errors could effect the general results, and
this showed that the possibility of vibrations at right
angles to the plate in process of manufacture causing
inequalities of disposition of the sensitive material
in process of drying, must be taken into consideration
This particular effect could not be due to a primary
structure of the X-ray beam, i.e., a structure ante-
cedent to all obstacles, such as metallic crystals,
whether in the wires, anti-cathodes, or glass of bulb
or plates. The experiment was arranged as follows.
Four recording plates, two made by the well-known
380
KNOWLEDGE.
October. 1913
Ilford Company, and two by the Imperial Plate
Company, of Cricklewood, were placed parallel, one
behind the other and a thick lead screen. The
plates were normal to the rays, but their edges were
at various angles to the horizontal, none of them
being the " way " of the plate-process. The distance
between the plates was a few centimetres, and that
of the first plate to the platinised-nickel anti-cathode
of a water-cooled X-ray bulb was fifty centimetres.
A constant current of -7 milliampere was passed
through the bulb, and the exposure continued for
eleven hours. Dark parallel bands showing a crossed
system appeared on all the plates, but these are not,
as they should be if one continuous form or structure
of radiations had been transmitted through the
series, in some one definite relation to the images
of three small circular apertures in triangular form
which had been made in the lead screen. Similar
bands, however, in so many other experiments have
been found in a definite quadrilateral pattern that
chance variations in the plate process or in develop-
ment can scarcely be the cause, though some definite
variations causing an inequalityof absorbing substance
may be. It appears that such causes varying the
effect must be considered as one of the inevitable
disadvantages of the photographic method, which
even in the case of experiments with crystals, giving
reflections or spots of variable form, should be
checked by such devices as we have used, or even by
the ionisation method. Mr. Keene, in a recent
letter to Nature, seems to suggest the convertibility
of the spots and bands by the mechanical structure
of rolled metals.
Inference is either direct or indirect. A thoroughly
instructive experiment does not allow one to escape
its lesson. But there is another kind of inference,
less trustworthy, but still necessary, to guide re-
search, which demands theoretical knowledge or
ingenious insight into analogy. No doubt one
must first adopt the method of frontal attack which
leads to the inevitable form of inference, yet after-
wards probabilities or speculative suggestions may
be tolerable or even useful.
Now, if the X-rays are simply light, the reasons
which may compel them to appear different may be :
(1) that the velocity is higher ; (2) that the mass of
the constituent rays or particles may be greater, the
total momentum being higher on one or other of
these grounds. I prefer to suppose that it is the
velocity, considered as a function of the inertia or
primary property of resistance, which is greater than
that of ordinary light.* It does not appear that
experiments have yet rendered untenable this
reduction of light and matter to one and the same
substantial theory of electrical resistance. If not, it
may form a simple aim or guiding hypothesis which,
being proven, would constitute an advance towards
the simplicity of generalisation. One or two salient
facts which tend in support of such a theory may be
mentioned here, not because they prove it, but rather
that they are steps on the way. Thus the writer
found, following Tribe and Leduc, that if a
small quantity of potassium ferri-cyanide be com-
pounded with gelatine, and the mass subjected
to electric currents of low voltages, coloured rings
appear in the gelatine round the electrodes, and these
rings are undoubtedly due to the transport of ions from
one pole to the other after the chemical dissociation
of molecules. In one case a clear-cut impression
like a seal or intaglio was obtained round the zinc
electrode as though matter had been actually
scooped out and transferred to the other pole. Also
Scheffer, of Berlin, has recently shown that probably
particles of silver bromide in the gelatine of such
plates as were used for these X-ray experiments
explode and emit daughter particles having filaments
connecting them to the parents. It seems reasonable
to expect that there should be for freed electrons
some lateral principle of limitation of the distribution
answering to the vertical geometrical progression
discovered by Perrin for the arrangement of small
particles in fluids. For instance, he found (vide
" The Brownian Movement and Molecular Reality,"
translated by F. Soddy, F.R.S., page 42) that the
concentrations of granules were determined in five
equidistant planes, the numbers being 100, 116, 146
170, and 200, whereas the numbers 100, 119, 142,
169, and 201, which do not differ from the preceding
by more than the limits of an experimental error,
are in geometrical progression, the altitudes (repre-
sented in Gregory Vincent's construction as areas
or volumes) being in arithmetical progression. This
is also suggested to the ordinary observer by the
form of the smoke from volcanoes in still air, which
spreads out into a flat plate bounded on the under-
surface by what resembles a hyperbolic curve. Such
a principle, if based on numerical experiments such
as those of Perrin, with the granules of X-ray
plates, might tend in the direction of setting free the
logarithmic or hyperbolic curve from the special
mode of energy-action we know as gravitation,
giving us a counter-principle of levitation or atomic-
segregation through the cosmos acting, in general,
contrary to weight, which is conformable to much
recent research and speculation, including Professor
Bickerton's new astronomy.
;: This view was first expressed by the writer before Kaufmann and Abraham had given experimental evidence of it for
Cathode particles. Vide " New Theories in Biology," Zoological Record, 1899, where it is called the principle
of " Cumulative inertia."
THE FACE OF THE SKY FOR NOVEMBER.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 65.
Date
Greenwich
Noon.
Nov. i
„ 6
,, ii
,, i6
, 21
, 26
R.A. Dec.
h, m. 0
14 24-48.14-3
M 44"' I5'9
'5 4'3 I7'3
15 24-6 18-7
'5 45'4 I9'9
16 6-5S.20-9
Moon.
R.A. Dec.
17 3-0 S. 28*0
21 39.2 S. i6'9
1 13-2 N.10'3
5 29-7 N.28"3
10 14-0 N.12'9
14 35'5 S. 19-4
Mercury.
R.A.
Dec.
h
m.
«S
56-6
S.23-3
lb
».V7
24-1
ib
26 -4
24-1
ib
22-3
23-0
w
2-8
20 "6
15
37 -2
S-"7'7
Venus.
R.A. Dec.
h. m. o
12 53-8 S. 4-0
13 i6'8 6-4
13 40*1 8'7
14 3-7 11 -o
■4 27'7 "3"i
14 52-2S. 15-1
Mars.
R.A. De
h. m 0
7 30-1 N.23'1
7 35'9 23'i
7 4°'7 23"l
7 44'3 23'2
7 467 23'3
7 47'7N-23'5
Jupiter.
R.A. Dec.
h. m. o
18 56-3 S.23-1
18 59-8 23-0
19 3-5 22-9
19 7-4 22-8
19 1 1 '5 22-7
13 I5-7 S.22'6
Saturn.
R.A. De
h. in. o
5 5-4N.31-1
5 4'2 2I'I
5 2'8 2I*0
5 1-4 2i'o
4 59-8 21 -o
4 58*1 N.20-9
Uranus.
R.A. Dec.
h. m.
20 24-9
20 25-3
20 25-7
20 26-3
20 26*9
S.19'9
19-9
19-9
19-8
19-8
20 27-6 S. 19-8
Neptune.
R.A. Dec.
I o
1*0
°'9
0-7
°'5
°"3
N.20-I
20"I
20*1
20*1
20'I
N.20-I
Table 66.
Date.
Sun.
P B L
Moon.
P
Mars.
P B L T
Jupiter.
P B L L T T
121 2
Greenwich
Noon.
00 0
+ 24*6 +4-3 312-5
23*7 3*7 246*6
22*6 3'2 180*7
21*2 2*6 114*7
19*7 2*0 48*8
-fi8*o +i'4 342*9
+ 5"5
-«?*7
— 20 *9
- 3"i
+ *9'4
+ 17*1
0 0 0 h. m.
-14*4 +9*4 15*0 10 58 w
13*6 9"8 328*2 2 io e
13*0 io'o 281*7 5 2Z e
12*5 io*i 235*3 8 32 e
I2'i 10*1 189*3 ll 41 '
— i2'o + io"o I43"5 2 11 m
0 9 ° ■ h. m. h. m.
-6*8 -1 '5 304*5 292*4 1 32 * 1 53'
7*2 i"4 i2'8 322*6 9 30 e 1 3*
7*6 1*4 8 1 '2 352'7 7 38 * 0 13*
8*o 1 '4 149*4 22*9 5 46' 9 19 e
8*4 1*3 217*7 53*o 3 54' 8 29 e
-8*8 — 1*3 285*9 83*1 2 2 e 739*
„ 6
„ 16
26
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Mars, T is the time of
passage of Fastigium Aryn across the centre of the disc. In the case of Jupiter, Lx refers to the equatorial zone; L2 to
the temperate zones; Tx, T2 are the times of passage of the two zero meridians across the centre of the disc ; to find inter-
mediate passages apply multiples of 9h 50im, 9h 55jm respectively.
The letters m, e, stand for morning, evening. The day is taken as beginning at midnight.
The asterisk indicates the day following that given in the date column.
The Sun continues his Southward march, but with slacken-
ing speed. Sunrise during November changes from 6.53 to 7.44,
sunset from 4.35 to 3.53. Its semi-diameter increases from
16' 9" to 16' 15". Outbreaks of spots in high latitudes should
be watched for.
Mercury is an evening star till 23rd. It reaches greatest
elongation (23£° E) on 2nd, but, being South of Sun, is not
well placed for observation by Northern observers. Illumina-
tion diminishes from § to Zero, then increases to iV Semi-
diameter increases from 3" to 5".
Venus is a morning star, rising 2 hours before the Sun.
Semi-diameter diminishes from 5i" to 5i". At beginning of
month A of disc is illuminated; at end of month 3$. Being
North of Sun it is favourably placed for Northern observers.
The Moon.— First Quarter 5d 6h34me; Full 13d 11" llme ;
Last Quarter 21d 7h 56m m. New 28d lh 41m m. Apogee
9d 4h m, semi-diameter 14' 46". Perigee 25d 6h m, semi-
diameter 16' 22". Maximum Librations, ld 7° N, 2d 7° W,
16d 7° S„ 17" 5° E, 29d 7° N, Dec ld 6° W. The letters
indicate the region of the Moon's limb brought into view by
libration. E. W. are with reference to our sky, not as
they would appear to an observer on the Moon (see Table 67).
Table 67. Occultations of stars by the Moon visible at Greenwich.
Date.
Magnitude.
Disappearance.
Reappearance.
Star's Name.
Mean Time.
Angle from
N. to E.
Mean Time.
Angle from
N. to E^
1913.
Nov. 1
„ 5
,, 8
„ 14
„ 16 ...
„ 16
„ 18 ...
„ 18 ...
BAG 5838
27 Gapricorni
BACX129
66 Arietis
BD + 27°88o
136 Tauri
47 Geminoruni
HAC 2383
6-8
6-i
6 3
6-1
7-0
4-6
5-6
6-5
h. m.
4 5"
6 12 e
3 39 «
6 29 m
6 1 t
2 8 m
5 38 m
129*
3'
101
118
103
79
27
h. m.
7 22 e
4 31 *
7 hot
5 3i '
6 49«
3 20 m
5 49 m
269°
"95
223
248
242
3°4
9
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
381
382
KNOWLEDGE.
October, 1913.
Mars is a morning Star, in Gemini, semi-diameter 6", defect
of illumination over a second. It passes its stationary point
on November 27th, and will reach Opposition early in January,
so the season of observation has commenced. The North
Pole is now turned towards us.
J upiter is now very low in the West. Polar semi-diameter,
16" in mid-November.
Table 68.
Day.
West.
East.
Day.
West.
East.
Nov. I
413 <
D
2
Nov. 16
24
O
'3
,. 2
42 (
)
13
.. 17
421
0
3
»» 3
4 <
J
3 2»I«
„ 18
4
©
23
.. 4
41 (
)
23
.. 19
4
0
3'
.. 5
423 <
j
1
„ 20
4321
O
., 6
3421 (
)
ii 21
43
O
21
.. 7
3 (
J>
412
ii 22
43'
O
2
,, s
3i <
)
24
.. 23
42
O
3i
.. 9
2 (
J
134
., 24
21
O
43
.. 10
2 '
1
34 «•
.» 25
O
1243
,, ii
1
J
234
„ 26
O
234 !•
., 12
2
D
14
,. 27
231
O
4
321 <
5
4
„ 28
3
O
14 2«
.. 14
3 <
J
214
.. 29
3i
O
24
» '5
3i <
J
42
„ 30
2
0
14 3«
Configuration at 5h e for an inverting telescope.
Satellite phenomena visible at Greenwich, ld 7h 55m I. Oc.
D., 8h Om II. Tr. I.; 2d 5h llm I. Tr. I., 6h 21m I. Sh. I.,
7h 30m II. Tr. E. ; 3d 5h 50m 20s I. Ec. R.. 7h 56m 52" II.
Ec. R.; 5d 6h44m III. Sh. E. ; 9d 7" llm I. Tr. I.; 10d4h24m I.
Oc. D., 5h 31m II. Oc. D.; lld 5h 5m I. Sh. E. ; 12d 5n 5m
II. Sh. E., 6h 22m III. Tr. E., 7h 14m III. Sh. I.; 17d 6h 23m
I. Oc. D. ; 18d 4h41m I. Sh. I., 6h 0m I. Tr. E., 7h 0m I.
Sh. E.; 19d 4h 8m 59s I. Ec. R., 4h 47m I. Sh. I., 5h 42m II.
Tr. E. ; 23d 4h 48m 389III. Ec. R. ; 24d 5" 6m 16" IV. Ec. D.;
25d 5h 42m I. Tr. I.; 6h 36m I. Sh. I.; 26d 5h 37m II. Tr. I.,
6h 3m 52" I. Ec. R., 28d 5h 10m 49" II. Ec. R. All these are in
the evening hours, the planet setting before midnight. Atten-
tion is called to the double eclipse of 3d. The eclipses take
place to the east of the disc, or to the right in an inverting
telescope.
Saturn is a morning star, in Taurus, in a good position for
observation. Polar semi-diameter 9 J". P. is — 4°-7; ring
major axis 47J", minor 21". The ring is very widely open.
It is of interest to examine the exact amount of overlap
beyond the planet's pole.
East Elongations of Tethys (every fourth given), ld 5h-4m,
8d6h-5e, 16" 7h-7*n, 23d 8h-9e, Dec. ld10h-lm; Dione (every
thirdgiven),3d10h-3m,lld3b-3e,19d8h-3e; 28dlh-2w; Rhea
(every second given), 8d 10h-9e, 17d llh-5e, 27d 0b-2*n.
For Titan and Iapetus E.W. mean East and West Elonga-
tions; I. Inferior (North) Conjunctions, S. Superior (South)
ones. Titan,2d3h-7eI.,6d0h-leW.; 10d llh -3m S., 14d lh-9e
E., 18dl"-6de I., 22d9h-8m W., 26d9h-0m S., 30d llh-5mE.;
Iapetus, 8d 8b-2m W., 27d 2-4bw S.
Uranus is an evening star. Semi-diameter, lj". At lf° S.
of p Capricorni.
Neptune is a morning star, entering Cancer. Stationary
at beginning of November.
Meteor Showers (from Mr. Denning's List) : —
Radiant.
Date.
K.A. Dec.
Nov. 1
4°3 + 2°2
Slow, bright.
„ 2
58+9
Slow, bright.
„ 10-12 ...
133 + 3'
Very swift, streaks.
,, 14-16 ..
150 + 22
Leonids, swift, streaks.
„ 16-28 ...
154 + 41
Swift, streaks.
,, 20-23 •
63 + 23
Slow, bright.
,. 17-23 ...
25 + 43
Andromedids, very slow,
trains.
„ 25 t.
Dec. 12
■ 89 + 73
Rather swift.
,, 30
190 + 58
Swift, streaks.
Double Stars and Clusters. — The tables of these given
last year are again available, and readers are referred to the
corresponding month of last year.
Variable Stars. — Tables of these will be given each
month ; the range of R. A. will be made four hours, of which two
hours will overlap with the following one. Thus the present
list includes R.A. 0h to 4h , next month 2h to 6h , and so on.
Table 69. Non-Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Maximum.
SS Cassiopeiae
h. m.
0 5
•
+ 51 -I
8-510 n-7
d.
139-6
Sep. 6.
TCeti
0 17
-20 -5
54 to 69
280-6
Oct. 16 (min.)
T Cassiopeiae
0 19
+ 55 '3
6-7 to 12- 5
443 '0
Oct. 7.
TU Cassiopeiae
0 22
+ 50 -8
7.7 to 85
59
Oct. 29.
TU Andromedae
0 28
+ 25 "5
7 ■ 7 to II
317
Oct. 27.
RX Cephei
0 43
+ 81 -5
7-410 7-9
130
Oct. 24 (min.)
RV Cassiopeiae
0 48
+ 46 9
8 to 13
327
Oct. 24.
ZCeti
1 2
- 1 -9
8-8 to 13-5
184-5
Oct. 6.
S Piscium ...
1 >3
+ 8-5
8-2 to 14 7
4°4 '45
Sep. 6
X Cassiopeiae
1 5'
+ 58 -8
8'4 to 12 2
367-0
Nov. 22.
R Arietis
2 11
+ 24 1
7-5 to 12'7
18666
Sep. 12.
R Ceti
2 22
- 0 6
7'5 to 12-8
166-88
Oct. 20.
U Ceti
2 3°
-J3 '5
6-6 to 12- 7
235 2
Dec. 8.
R Trianguli
2 32
+ 33 9
5-9 to 11. 1
265 -4
Dec 27.
Y Persei
3 22
+ 43 9
8' 2 to to- 4
254'9
Nov. 2.
/3 Lyrae minima Nov. 8d 5he, 21d 3he, Period 12d 21 -8h.
Algol minima Nov. 5d 2h 8mw, 7d 10h57me, 10" 7h 46me, 13d 4" 35me, 28d 0h 40m m, 30d 9h 29me, Period 2d 20-8\
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
THE NUMBER OF VISIBLE STARS.— The enquiry as
to the number of stars in the entire heavens that can be seen
with our best telescopes, or photographed by them, is a very
interesting one. Various estimates have been given at
different times, some going as high as a thousand millions,
but it now appears that this number is greatly in excess of
the truth. Naked-eye observers are often surprised on
hearing that they can seldom see more than two thousand
stars at a time. In the same way, when one has seen some
of the rich fields of the sky in a large telescope, with the
whole region thickly studded with stellar points, one is apt to
make extravagant estimates of the number in the whole sky.
Mr. R. H. Tucker has a paper in Publications of the
Astronomical Society of the Pacific for August, in which
he gives, by the collation of various authorities, the number
which can be seen visually (i.e., down to the 17th magnitude)
as forty million, or a thousand to the square degree. This is
about the same as the number of inhabitants of Great
Britain. He gives the number that can be photographed
(i.e., down to the 20th magnitude) as a hundred millions. It
is well known that the relative increase in number for each
additional magnitude falls off for the fainter stars, indicating
either an absorption of light in space or our actual approach
to the limits of our system. In any case, the number given
must be less than the real number of stars in our system, for
there are many stars of small intrinsic luminosity which are
faint even when near us, and would be invisible in the more
remote parts of the system. Of course, no account can be
taken of dark, burnt-out stars, as we have no means of
forming an estimate of the number of these. If we suppose
the star density to remain constant throughout our system
(which is probably not true) and take the number of stars
within sixteen light-years as eighteen, then a hundred million
stars would fill a sphere of radius three thousand light-years,
which is the same value as Newcomb's for the distance of the
outer parts of the Galaxy. But the value rests on such
doubtful assumptions that it is only a rough guess.
The same publication contains an article by H. D. Curtis
on the unit to be used for stellar distances. He advocates
the continuance of the use of the light-year, instead of the
astron or parsec, on the grounds that it is more easily grasped
by the general reader, and also that it is known to one part
in ten thousand, or ten times as accurately as the solar
parallax. As regards the first point, I do not think that anyone
proposes to drop the light-year for popular purposes ; the
second does not seem to me to carry much weight, in view of
the fact that star-distances can only be found in terms of the
sun's distance, and also that no stellar parallax is trustworthy
to more than two significant figures. The parsec is advocated
because it enables us to pass almost instantaneously from
parallax to distance, thus saving a large amount of mental
arithmetic.
There is one point in his paper which gives some food
for thought : he speaks of the light-year as being six trillion
miles. This is an instance of the American system that calls
a thousand millions a billion, a thousand billions a trillion, and
so on. The English system makes a million millions a billion,
a million billions a trillion, and so on. It has the logical
advantage that the bi-, tri-, and so on, express the powers to
which a million is raised, whereas the prefixes are meaningless
on the American system ; moreover, there is the important
advantage that fewer new names are introduced in the
expression of large numbers. The adoption of a uniform
system of arithmetical notation throughout the world seems a
more important matter than the question of the relative
advantages of the light-year or the parsec.
GIANT AND DWARF STARS.— Professor H. N. Russell
gave an interesting address on this subject at the June
meeting of the Royal Astronomical Society, and a summary
of it appears in the Observatory for August. He takes all
the stars for which parallaxes worthy of any confidence have
been obtained, and classifies them according to intrinsic
brightness and spectral type. He concludes that all the
intrinsically very faint stars are red, of spectral type K or M,
while all the stars of types A, B are much brighter than the sun.
There are, however, a number of red stars that are intrinsically
very bright, such as Arcturus, Aldebaran, Antares. The stars
of types K, M are either much brighter than the sun or much
fainter. Of the dwarf stars of class M not one is visible to the
naked eye, although one is the second nearest star in the
heavens.
Discussing the masses, he gives reasons for supposing that
these differ among themselves much less than the intrinsic
brightness, and that the dwarf stars are those of very low
surface brightness.
He conjectures that the giant red stars are at an early stage
of low temperature, low surface brightness, low density, great
surface, and consequently great total light. As each contracted
it would grow hotter and whiter, but smaller, so that its total
light would not change much. When hottest it would have a
spectrum of type A or B ; only massive stars would attain the
highest temperature, and stars of types A, B are found to be
massive in those cases where their mass can be determined.
After passing the maximum temperature it would grow smaller,
redder, and duller, i.e., it would pass to the class of dwarf stars.
According to this view the difference between giants and
dwarfs is not one of total mass, but of age and degree of con-
densation. It is, of course, rather curious that stars in
such different conditions should give the same type of
spectrum, i.e., that type M should occur both at the
beginning and the end of a star's career; but the evidence
seems strong that these M stars do form two different classes.
Professor Russell hopes to publish his researches more fully
next year, and we may look forward to their appearance
as likely to throw new light on the life-history of the stars.
A NEW COMET. — The second comet of the year was
found by Dr. J. Metcalf, on September 2nd, being his third
discovery of the kind. It was of the tenth magnitude, in
Right Ascension 6h 50m, North Declination 57°. Daily
motion minus lm 16s, North 34'. If an ephemeris for October
should be ready in time, it will be given in another column,
with " Face of the Sky " for November.
Later. — The comet was nearest to the Sun on July 20th, but
approached the Earth in September so as to grow slightly
lighter ; but it will not be conspicuous. Another faint comet
was found by Neujmin on September 3rd.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
BOTANY AT THE BRITISH ASSOCIATION.— The
doings of Section K (Botany) at the Birmingham meeting
presented various features of interest. For the first time
in the history of the British Association, a lady was chosen as
President of a Section, and in her address Miss Ethel Sargant
referred in felicitous terms to this innovation as an honour
done to herself as a botanist, but also as an act of generosity
— greater because done in the face of custom and prejudice.
RECENT RESEARCH ON EMBRYOLOGY OF
ANGIOSPERMS— Miss Sargant, after a tribute to the work
and influence of the late Lord Avebury, as a representative of
a small but distinguished class of naturalists, to whom she
383
384
KNOWLEDGE.
October, 1913.
referred as " the salt of the subject, preserving it from the
worst effects of a purely professional and academic standard,"
gave an interesting account of the development of botanical
embryology since 1870. As might have been expected from
the large share which the President herself has taken in the
investigation of seedling structure in Angiosperms and its
phylogenetic interpretation, the address was limited to
Angiosperm embryology, though this is, of course, in itself a
sufficiently wide field. As pointed out by Balfour, embryology
ought, strictly speaking, to deal with the growth and structure
of organisms during their development within the egg-
membranes before they are capable of leading an independent,
existence, but modern investigators have shown that such a
limitation of the science would have a purely artificial
character, and the term " embryology " is now employed to
cover the anatomy and physiology of the organism during the
whole period included between its first coming into being and
its attainment of the adult state. The older botanists used
the term in the narrower sense, including the study of the
embryo-sac and the structures contained in it before the
formation of the unfertilised egg-cell as well as the fertilisation
of the latter and its subsequent divisions, but they did not
proceed beyond the resting stage of the embryo within the
ripe seed. Here, as in zoology, this division is arbitrary and
inconvenient ; hence in the following remarks embryology is
taken to include every stage in the development of the plant
from the first division of the fertilised egg-cell to maturity.
Systematists from Caesalpino onwards have paid much
attention to the structure of the seed, and were indeed forced
to study the embryo because its characters are often of
systematic importance ; for instance, the number of cotyledons
is the most constant character separating the two great
classes of Angiosperms, while the presence or absence of
endosperm in the ripe seed, besides being important
systematically, determines the function of the cotyledons
after germination, and thus influences their structure pro-
foundly. Hence botanists became familiar with the structure
of the embryo in the ripe seed before they had traced its
origin from the fertilised egg-cell, or followed its development
after germination. Since the early history of the embryo was
a sealed book to observers without the compound microscope,
work on the external morphology of seedlings preceded that
on the formation of the embryo. In the school of seedling
descriptive work the greatest name is that of Thilo Irmisch
(1815-1879), whose work was neglected by the succeeding
generation owing to the rapid development of microscopic
botany, starting from Hanstein's classic work (1870) on the
divisions of the fertilised egg-cell, which laid the foundation of
botanical embryology in the narrower sense — the study of the
embryo from origin to germination. The period in the plant's
history beginning with the first division of the fertilised egg
(a natural epoch, since a new generation dates from it) and
ending with the formation of the ripe seed (a true physiological
epoch, since it corresponds with a complete change in the
conditions of life) would seem very well defined ; but
experience has shown that here, as in zoology, embryologists
lose more than they gain by dividing the subject in this way —
one group of investigators beginning their work where the
others end theirs — and that this division is neither so simple
nor so natural as it appears at first sight. It is not simple
because the embryo is not always completely dormant during
the interval between the formation of the ripe seed and the
first steps in germination. In most Monocotyledons and
many Dicotyledons the embryo is an almost undifferentiated
mass of meristem when the seed first ripens, and becomes
differentiated internally and externally by degrees during the
interval before germination : this is often called the matura-
tion of the seed, and it is quite distinct from its ripening.
Maturation is a process characteristic of the seeds of geophilous
plants (plants with bulbs, corms, rhizomes and other perennat-
ing underground organs) which commonly lie in the ground
for a year at least before germination ; the embryo of such
plants is not comparable morphologically with that in the seed
of an annual which may have ripened at the same time, since
the embryo of the annual has root, stem, and leaves besides its
cotyledons, and is ready to germinate immediately on the
return of spring. Hence the morphologist must continue his
study of the geophilous embryo throughout the maturation
period if he is to compare it with that of the annual ;
even then he will find it less advanced than the annual
embryo though both be examined as they break out of
the seed, for the geophyte may, perhaps, be four or five years
before it flowers, while the annual has to complete its whole
life-cycle in a single season. The division of the subject into
two parts, the first ending with the embryo in the ripe seed,
is also an unnatural one, even if the time of maturation be
included in that first period ; for the structure of the embryo
cannot be completely understood by reference to its past
alone. The observer must expect adaptive characters of
three kinds : — (1) those imposed on the embryo in the past
by its development within the embryo-sac while it is still
parasitic on the parent plant ; (2) certain adaptations to the
process of germination itself ; (3) characters which will be
useful after germination. Before the utility of these characters
can be fully understood the development of the seedling must
be followed for some time. In short, the structure of the
embryo is dependent upon its future as well as on its past,
and a division of the subject which excludes that future is, as
Balfour says, purely artificial.
The work done in recent years on the anatomy of the
seedling has therefore not only completed Irmisch's work on
its external morphology, but has also thrown light on the
problems of early embryology, attacked by Hanstein and his
immediate followers. These problems are of two kinds,
relating to the internal anatomy or the external morphology
of the embryo. Hanstein himself was chiefly interested in
the former, and his work disposed once for all of the
possibility that the embryo of Angiosperms might possess
an apical cell in the earlier stages of its growth as a
reminiscence of its cryptogamic ancestry. One general result
of work on the embryo since Hanstein's time has been
to discredit phylogenetic theories based on its early
history ; indeed, it was hardly to be expected that a small
mass of meristem, developing within a confined space and
feeding parasitically on the tissues of the mother-plant, should
preserve ancestral features. Still, Hanstein and his successors
did good service in elucidating the growth of the pro-embryo
from the fertilised egg-cell ; its division into suspensor and
embryo ; the general development of both, and the appearance
of external and internal differentiation in the embryo before
germination.
While some of Hanstein's general conclusions as to internal
anatomy have become the common property of text-books, for
instance, the early differentiation of the dermatogen and its
subsequent development into the epidermal system, he was
less successful in demonstrating the initial independence of
plerome and periblem, and their relation to the vascular
system of the mature stem. The early differentiation of
plerome and periblem from the inner tissues of the embryonic
axis and their continued formation at the growing- points of
root and shoot are processes which demand the most careful
investigation on account of their bearing on the stelar hypo-
thesis.
(To be continued.)
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon.), F.I.C.
TESTING THE VITALITY OF SEEDS— An
ingenious method of ascertaining whether a seed is living
has been devised by Mr. S. Tashiro, and an outline of his
communication on this subject to the Eighth International
Congress of Applied Chemistry is given in the Analyst (1913,
XXXVIII, 370). The method depends upon the fact that
so long as a seed is alive it liberates carbon dioxide. This
gas can be detected and estimated by means of a special
apparatus which is so sensitive that it can measure as little
as one ten-millionth part of a gramme. It was found with
the aid of this apparatus that when a living seed was crushed
October, 1913.
KNOWLEDGE.
385
or bruised its activity was stimulated, and that it then
emitted a much greater quantity of carbon dioxide.
DUST EXPLOSIONS. — Interesting experiments have
been made by Mr. W. R. Lang (Proc. Chem. Soc, 1913,
No. 168, 1911) to test the liability to explosion of finely
divided starch and coal dust when mixed with air. The fine
powder was allowed to fall into the upper end of a vertical
glass cylinder about seven feet long by four inches in
diameter. Through the sides of this open glass chamber,
about half-way down, were fused two wires connected with
an induction coil, so that a spark could be passed through the
mixture. When this was done the dust, whether of coal,
starch or lycopodium, ignited explosively; the combustion
spread throughout the length of the tube, and flames issued
from each open end. Analogous results were produced by
applying a light to the end of the tube.
Microscopic measurements of the particles of different kinds
of dust used in the experiments were made, and the
average results calculated into the total areas of the
substances per one hundred grammes. In this way the
following results were obtained : —
Mean diameter
Total surface area
Substance.
of particles in
for 100 grammes
millimetres.
of substance.
Square Metres.
Lycopodium powder ...
0-028
20-92
Maize starch
0-0122
32-78
Coal dust (a) medium ...
0-012
33-33
„ „ (b) fine
0-0016
250-00
" Pyrophoric carbon " ...
0-00125
332-00
" Pyrophoric iron "
0-0054
15-08
GEOGRAPHY.
By A. Stevens, M.A., B.Sc.
A PHYSIOGRAPHICAL STUDY IN NEW ZEALAND.
— In the September Geographical Journal there is an •
account of the physiography of the middle Clarence valley,
New Zealand, by Mr. C. A. Cotton. The Clarence River
rises near Mount Franklin, in North Canterbury, and after
flowing in a southerly direction for some forty miles, turns
sharply towards the north-west, flows for fifty miles between
the Seaward and (Inland) Kaikoura Ranges, and is again
sharply deflected to the south. The paper in question dis-
cusses the portion of the course which lies between the
Kaikouras.
The geology of the country has not been fully worked out'
and, as so frequently happens in New Zealand, presents some
difficult and disputed questions. Generally it may be stated
that the underlying older rocks are of about Carboniferous
age. They are much contorted, and the system of folding
has not been described. These rocks have been extensively
denuded, and probably were cut down so as to present a
surface of low relief. Newer deposits, of age ranging from
Cretaceous to Pliocene, covered them; on a basal con-
glomerate rested soft mudstones, and the sequence passed up,
through resistent beds of limestone and flint and soft marls,
to a top layer of hard conglomerate. Earth -movements on a
large scale have affected the area and produced two huge
anticlines, or probably anticlinoria, separated by an
asymmetrical syncline, the north-west limb of which gave
way, and is represented by a reversed fault of enormous and
undetermined throw. The anticlines build the Kaikoura
Ranges, while the syncline has been occupied by the Clarence
River, which in its middle course is therefore a consequent
stream.
In the cycle of denudation which ensued, the covering of
newer rocks was removed from the mountains by the streams
of the Clarence system, a flat floor of mudstone being left in
the valley. This lies closer to the north-west side of the
valley, where it is faced by the scarp of the limestone, and the
want of symmetry of the valley is a direct consequence of
the asymmetry of the syncline. A subordinate uplift follow-
ing rejuvenated the stream, already at base level, and it
proceeded to cut a gorge in the valley floor. The courses of
rivers further to the north and to the south are transverse to the
middle Clarence, and consequently to the axis of the
mountains, and these, Mr. Cotton considers, are antecedents,
whose courses were determined by a simple regional uplift
earlier than the folding. By the latter movement the
Clarence alone was diverted, and only in its middle course,
where the rise of the land reached its maximum. The lower
Clarence follows the course of an antecedent stream. The
valley slopes and floor of the middle Clarence are trenched
by streams antecedent, consequent, and subsequent, some
graded, some still cutting. The limestone ridge is dissected
by superposed consequents from the Kaikoura Range which
often join twos or threes just before clearing the ridge, and so
cut out pyramidal hills of limestone rather lower than the
adjacent part of the scarp. The fault-plane gives rise in
places to noticeable topographical features. It facets spurs
from the Kaikouras (long spurs from the Seaward Kaikouras
are also faceted — but by the stream), while in the lower part
of the valley it is marked by a bench, some twenty feet wide,
which represents an earthquake fissure. Evidences of
glaciation are wanting in the area, though it has been held
that the valley is deeply ice-worn. Mr. Cotton believes that
glaciers have always been absent, as they are now, for the
steepness of the slopes prevents the accumulation of reservoirs
of snow.
OCEANOGRAPHY OF THE MEDITERRANEAN.— An
article in Nature, for September 4th, draws attention to the
report of the Danish Oceanographical Expeditions of 1908-10,
to the Mediterranean and the adjacent seas. It is found that
the Mediterranean is divided into two basins by a submarine
ridge four hundred metres below sea-level at the deepest
points, which continues the line of Italy and Sicily to the
north coast of Africa. Of these basins the western is, for the
most part, two thousand to three thousand metres deep, the
eastern generally deeper, soundings of more than four
thousand metres having been made. The main interest
centres in the movements of the water. The rainfall balances
less than one quarter of the loss by evaporation, and the
water-level is maintained by an inward current from the
Atlantic which runs from one to three knots. As a direct
consequence the pressure inside is increased, and a stream
sets out towards the ocean at a speed which varies between
one half and five knots. Although the temperature is uniformly
so high as thirteen degrees at the depth of one thousand
metres, the unusual salinity, due to excessive evaporation,
raises the density of the water so much that the outgoing
current is a deep one. These currents are, of course, affected
by the tides, and the warm outward current is made by the
rotation of the earth to swing to the north and east in the
lower strata of the Atlantic. This may explain the occasional
high salinity in enclosed seas on the British coasts. Again,
the high precipitation in the area which feeds the Black Sea
and the Sea of Marmora makes these waters remarkably poor
in salts, and conditions exactly opposite obtain. But the
threshold of the Black Sea is so shallow that the deeper layers
of the water are stagnant, and the dissolved gas is hydrogen
sulphide ; hence only some forms of bacteria people the sea.
The water-circulation within the Mediterranean is complex
and incompletely described. It varies at different depths and
in different areas.
STUDIES IN GLACIERS.— From data, more or less
complete, covering a period of some dozen years, one might
conclude that at present there is a general tendency to retreat
of the ice-fronts of the glaciers of the world. From several
parts reports come in of the extension of the length of
glaciers, but the figures require careful scrutiny (Hans Hess,
Petermanns Mittcilungen, April), and when circumstances
386
KNOWLEDGE.
October, 1913.
more or less incidental are considered and the size and import-
ance of the various ice-streams taken into account, the
impression is produced that a longer period of study is
necessary, and in most cases more detailed records are
required. Those who make general statements covering the
phenomena of the whole globe raise not unfounded suspicions
that they are looking too keenly for unreasonable uniformity.
In Switzerland, if we eliminate small cirque-glaciers, which
are usually in a state of oscillation, only the Lower Grindelwald
glacier and the small glacier of the Sex Rouge show continued
advance (Annales de Geographie, July, and so on). In
Scandinavia in several important instances advances up to
one hundred and sixty metres are recorded ; but, on the whole,
the glaciers are in a state of oscillation, and no general statement
is justified. In Asia, New Zealand, and South America definite
information is wanting, but elsewhere it is stated there is a
general tendency to regression. In Alaska, however, certain
of the main glaciers have pushed forward their ice-fronts,
that of La Perouse, for example, having gained four hundred
metres. This growth followed upon earth tremors recorded
in 1899, and has been correlated with them. Hess prefers to
connect the advance with the abundant snowfalls of the end
of the nineteenth century.
Joseph Vallot (Comptes Rendus, CLVI, May, 1913,) gives
a record of temperature observations in glaciers at high
altitudes (four thousand metres) made during 1898, 1900,
1911. A diurnal variation up to 13° (centigrade) is observable
to a depth of -7 metre. Down to 7-5 metres the temperature
falls rapidly, and below that it varies between —12° and —13°,
remaining stationary at —12 -8° below fifteen metres. At the
depth of about one metre, it may be concluded, diurnal
temperature variation ceases, and the limit of the seasonal
variation is 7 • 5 metres. The grain of the ice grows from
■ 5 millimetre to 1-2 millimetres in diameter, apparently
without fusion, and the ice is impermeable. Hence neither
infiltration of water nor temperature variation, which ceases
at a relatively insignificant depth, can be an important factor
in producing the flow of glaciers.
By G,
GEOLOGY.
VV. Tyrrell, A.R.C.Sc, F.G.S.
GARNET AS A GEOLOGICAL BAROMETER.— The
petrological investigation of a peculiar manganiferous igneous
rock (kodurite) discovered by Dr. L. L. Fermor, of the
Geological Survey of India, in connection with his recent
survey of the manganiferous deposits of the Indian Empire,
has led to certain conclusions as to the mode of formation of
garnet (Records, Geological Survey of India, Vol. XLIII,
Part I, 1913). Typical kodurite is a plutonic rock consisting
of orthoclase, spandite (manganese garnet), and apatite.
Associated with kodurite is a garnet (spandite) rock. In
attempting to classify these rocks Dr. Fermor calculated their
analyses into the norm or standard mineral composition of
the American Quantitative Classification. The norm of
kodurite contained orthoclase, leucite, anorthite, hedenbergite,
wollastonite, tephroite, magnetite, ilmenite, and apatite ; whilst
that of the garnet rock was expressed as a mixture of anorthite,
hedenbergite, akermanite, fayalite, tephroite, and magnetite.
A comparison of the specific gravity of the mode (actual
mineral composition) with that of the norm (standard mineral
composition) showed that the kodurite occupied ten per cent.,
and the spandite rock twenty per cent., less room when
crystallised as the mode than as the norm. This indicated
at once that the crystallisation of kodurite and spandite rock
was conditioned by high pressure, necessitating a decrease in
volume as compared with the conditions of pressure under
which the norms might have crystallised from the respective
magmas.
If this be the true interpretation, garnet may be regarded
as a geological barometer, indicating especially high pressure
during its formation. Confirmation is found in the fact that
garnet is an abundant constituent of all the various rocks
associated with the kodurite series. Further speculation on
these lines suggested that eclogite is the high-pressure form of
gabbro, and consideration of the chemical analyses and the
specific gravities of these rocks supported this view. Since
the plutonic rocks, formed at great depths under pressure, are
typically non-garnetiferous, Dr. Fermor postulates the existence
below the plutonic zone of a shell characterised by garnets
wherever the necessary sesquioxide radicle is present. For
this shell is suggested the term infra-plutonic. Other
minerals, notably diamond, the high-pressure form of carbon,
may also be characteristic of the infra-plutonic zone, and
Dr. Fermor makes the interesting suggestion that the diamond
pipes of Kimberley, in which eclogites and garnets are found,
may be directly connected with the infra-plutonic zone.
PRESERVATION OF PLANT-FOSSILS IN LAVA.—
Some interesting examples of tree- moulds in lava are described
by F. A. Perrett (American Journal of Science, Vol.
XXXVI, August, 1913) from Kilauea. The basalt lava from
this great crater has sometimes invaded a forest of trees and
then flowed away, leaving an investment or casing of lava
upon a tree-trunk up to a height corresponding with the
greatest depth of the lava stream at that point. These are
known as the salient or projecting types of tree-mould, and
stand above the surrounding plain as a monument to the
original tree, which, if not destroyed at once by the basalt-
flood, soon dies and rots away.
In the sunken or ground type of tree-mould the lava has
invaded low ground, and has come to a standstill among the
trees. The latter, of which no trace now remains, have left
an impression of their forms down to the minutest detail upon
the lasting stone. These casts are found on the sides of
cylindrical openings, from three to five metres deep, in the
lava-plains. An excellent illustration in the paper shows the
faithfulness of these impressions of the rugged bark of the
trees upon the plastic lava. It is a matter for comment that
the trees were not destroyed by their " baptism of fire," long
before such impressions could be taken. If, however, the
resinous varieties be excepted, large tree-trunks, massive and
full of moisture, will resist carbonisation at least long enough
for a skin of cold, solid basalt to form in contact with them, and
thus provide a nearly non-conducting layer.
Similar plant-remains preserved in lava have been described
by Solorzano and Hobson from Mexico, where fragments of
maize were found in basaltic scoriae ; and by H. M. Cadell,
who has described a lycopod stem, twelve inches long,
embedded in olivine-basalt lava from the Bo'ness Coalfield.
Phenomena identical with those described by Perrett were
observed by F. A. Fouque on Etna, where the lava of the
1865 eruption flowed through a wood of lofty trees.
SAPPHIRE IN MULL.— Clear blue corundum has been
found by the Geological Survey in two localities to the west of
Carsaig, Mull. The mineral occurs in tabular hexagonal
plates, which are, however, too small and irregular to have
any gem value. In each case the crystals are found in
igneous rocks which have involved xenolithic masses of sedi-
mentary material. In one locality large xenolithic blocks of
baked sandstone and shale are involved in an igneous matrix
which is probably intrusive, and which encloses numerous
little sapphires. In the second locality the sapphires are
found in an irregular composite sill consisting partly of
andesitic felsite and partly of trachytic granophyre or syenite.
This intrusion is also full of xenolithic material, including
baked shale. The sapphires are found both in the latter and
in the igneous matrix.
METEOROLOGY.
By William Marriott, F.R.Met.Soc.
BEN NEVIS OBSERVATORY.— It is announced that a
tourist hotel is being built on the top of Ben Nevis on the site
of the former Meteorological Observatory. This hotel will
probably be the terminus of the four and a half miles railway
which it is proposed to construct when funds are assured and
sanction obtained to proceed.
It will, no doubt, be remembered that the Ben Nevis
October, 1913.
KNOWLEDGE.
387
Observatory was closed at the end of September, 1904, owing
to the lack of financial support. This observatory, which is
four thousand four hundred and four feet above sea-level, on
the highest spot in the British Isles, was established by the
Scottish Meteorological Society in 1883, and observations
were taken every hour, day and night, without a break,
frequently under very difficult conditions, for a period of nearly
twenty-one years. During the months of February and
March it was not uncommon for south-easterly gales to blow
for three or four days continuously at the rate of one hundred
miles an hour. On these occasions the observers had to go
out roped together or to crawl along the surface, otherwise
they would have been blown away by the wind. At other
times the rain would freeze as it fell, and so everything
became coated with ice, which continued to increase in thick-
ness almost indefinitely. During summer, or when the
temperature was above the freezing-point, the fog soaked
everything exposed to it, and so all the instruments outside
the observatory streamed with moisture, even though no rain
was actually falling; while in winter, or when the tempera-
ture was below freezing-point, the effect of the fog was to
cover everything with long feathery masses of rime or crystal-
line specks of snow. These continued to grow to great
lengths on the windward side until they broke off by their
own weight. In these circumstances it was impossible to use
self-recording instruments, and so the observers had to take
observations every hour, day and night.
The average temperature, rainfall, amount of cloud, and
hours of sunshine are as follows : —
Table 70.
Temper-
Rainfall.
Cloud.
Sunshine.
ature.
Inches.
Hours.
January
24° 0
18-33
8-8
22-4
February
23-8
13-55
8-3
42-3
March...
24-0
15-25
8-4
54-7
April ...
27-6
8-48
8-0
80-4
May
33-0
7-90
7-8
116-3
June
39-7
7-54
7-7
127-0
July
41-1
10-80
8-6
84-9
August
40-4
13-34
8-8
58-1
September
38-0
15-74
8-3
62-2
October
31-4
15-42
8-5
41-8
November
28-9
15-36
8-5
27-9
December
25-2
19-07
8-7
18-0
Year
31-4
160-77
8-4
736-0
As temperature decreases approximately at the rate of
1° F. every one hundred feet, the temperature at the summit
is usually about 15° lower than at Fort William; consequently
the snow on the top of the mountain remains nnmelted for the
greater part of the year.
BRITISH RAINFALL, 1912.— The publication of the
annual volumes of British Rainfall is always looked forward
to not only by meteorologists but also by engineers and
surveyors, and others who have any interest in rainfall
statistics. The volume for last year, 1912, has recently been
issued, and this includes the records of rainfall from more than
five thousand observers in Great Britain and Ireland. The
records confirm the popular opinion that the year 1912 was a
very wet one, as will be seen from Table 71.
The greatest amounts of rainfall recorded in the year were
205-17 inches at Crib Goch, on Snowdon, and 196-43 inches
at the Stye in Cumberland. The lowest amount was
19-24inches at Stifford, in Essex. It appears that the summer
of 1912 in England and Wales was wetter than any other
summer during the past fifty years, although the rainfall of the
summer of 1879 was nearly similar.
April, May, and September were the generally dry months,
and March, June, August, and December the wet months.
Table
71.
Rainfall for
1912.
Difference from Average.
England
Wales ...
Isle of Man
Scotland
Ireland ...
39-31 in.
56-19 „
41-85 „
41-77 „
44-06 „
+ 7-25 in. or 23 per cent.
+ 9-01 „ „ 19 „ „
+ 0-22 „ „ 1 „ „
+ 4-70 „ „ 11 „ „
+ 3-43 „ „ 8 „ „
The most remarkable feature of the year was the un-
precedented rainstorm of August 25th-26th, in East Anglia,
when more than six inches fell over an area of four hundred
and forty-six square miles, and more than seven inches over
an area of two hundred and forty-one square miles, while more
than eight inches fell between Norwich and Brundall.
Serious Moods resulted from this extraordinary rainfall : the
flood at Norwich was fifteen inches higher than the previous
highest one in 1614.
Dr. H. R. Mill, the director of the British Rainfall Organisa-
tion, has been obliged, acting under medical advice, to take
a long and complete rest. We trust that this cessation from
work will restore him to health. During his absence the work
of the organisation will be carried on under the joint direction
of Mr. R. C. Mossman and Mr. C. Salter.
AEROPLANES AND WEATHER.— The recent attempt
of Mr. Hawker to win the Daily Mail prize of £5,000 in the
waterplane race round Great Britain reminds me of a letter I
received a year ago from a correspondent, who attributed all
the bad weather to the action of aeroplanes. The letter was
as follows :
" Sir, — Has it not occurred to you and others that the bad
weather, and consequent likelihood of famine for us all, is due
to this interference with Nature's laws ? This foolish so-
called ' flying ' is cutting up the atmosphere. It is well
known that heavy firing of guns brings down rain by con-
cussion, and it stands to reason that great steel propellers,
slashing the air for great distances, is bound to cause violent
disturbance of the weather. Wherever there is ' flying,'
there come storms of wind and torrents of rain, and bitter
cold as by an electric fan. So do stop this rubbish lest we all
starve."
The writer of the above evidently has a very decided pre-
judice and hatred against flying machines, and also is ready
to attribute good or bad weather to unknown influences.
One often hears many other people give expression to some-
what similar opinions as to the weather, although it is very
doubtful if they really think anything about the matter. A
few years ago very decided opinions were expressed by many
people who asserted that the wireless installations erected at
certain places round the coast had quite altered our weather.
Up to the present, however, the ordinary meteorological
observations have not shown that any perceptible effect has
been produced by these things on the weather.
The cheap newspaper press is also much given to the use of
terms and adjectives about passing events — even about the
weather — which are great exaggerations and often incompre-
hensible. Anything that in the slightest degree interferes with
pleasure, sport, or comfort is at once described in terms of
execration. As an instance of this the following example
may be given. Thursday, August 28th, was very fine and
bright, but the next day, Friday, was misty, damp, and close,
with a slight thunderstorm and little rain between 10 and
11 a.m. On Saturday morning a placard of one of the
London daily papers was wholly taken up in large type with
the words " Grumpiest Day of the Year." It is difficult to
understand what the editor meant by such an expression. He
could hardly have realised that a few hundredths of an inch
of rain arc quite insignificant compared to the eight inches
which fell in Norfolk only twelve months previously, as
mentioned in the preceding note.
388
KNOWLEDGE.
October, 1913.
MICROSCOPY.
By F.R.M.S.
AN IMPROVEMENT IN THE HAND MAGNIFIER.
— Mr. W. G. Williams, of the Swansea Field Naturalists'
Society, has sent a sketch of a very simple way of using a
magnifier so as to have one hand free. Usually the magnifier
is held in one hand, and the specimen in the other, and if it is
desired to arrange the specimen or refer
to a book, the magnifier has to be set
down, and the observation begun again.
It will be seen by reference to the drawing
that hole A (see Figure 397) is made of
sufficient size for the frame of the magnifier
to rest on the top of the third finger of the
left hand, the specimen under examination
is held between the thumb and first finger,
and the right hand is free to do dissecting or for other
purposes (see Figure 398). The improvement costs nothing.
TERMITES. — A short time ago a friend
living in the Orange Free State sent me some
specimens of the Termites (usually miscalled
White Ants) found in that district, which
are apparently quite as mischievous to wood-
work there as their relatives in India and
elsewhere, and in general appearance they
do not greatly differ.
The Royal Cell containing the Queen was
dug up from about four and a half feet below
the surface of the ground ; it was oven-shaped
and measured five inches in length by two
and a quarter inches in width, with a height
in the centre of one inch. It was perforated
by numerous small holes giving access to
the workers and soldiers, but, of course,
useless as a means of exit for the Queen,
whose distended abdomen measured three
inches in length and was three quarters of an
inch in diameter at its widest part. The
workers measured -175 inches, were pale
yellow in colour and without eyes, for which
they had no need, since they carry on their
operations in darkness, their home duties
being mainly to feed the Queen and to remove
the eggs as laid. Each bore a pair of monili-
form antennae of fifteen joints, and in addition to the usual
mouth organs was armed with a pair of strong mandibles
eminently adapted for the destruction
of wood. The soldiers were consider-
ably larger in size, measuring • 3 inches,
of which the head alone was rather
more than one third ; they were dark
red in colour and in addition to
antennae resembling those of the
workers, were furnished with a pair of
formidable mandibles worked by
muscles of great power. On carefully
comparing these mandibles with
available figures, and particularly with
those of Termes bellicosus at the
Natural History Museum, I found
that they differed materially in shape,
and regarding this as indicating a different species I did
my best to identify it. In this, however, the Museum
experts were unable to help me, and a reference to the learned
Professor who is regarded as the greatest European authority
on the subject only resulted in his opinion that though it
appeared to be a new species he would not definitely commit
himself on the matter from the drawings and specimens sub-
mitted. I therefore give drawings of the mandibles of these
soldiers (see Figure 399) and also of those of the nearest
form met with, T. bellicosus (see Figure 400), thinking
that the comparison may be of interest to some of our
readers. R. T. L.
Figure 397.
Figure 398
Figure 399.
Mandibles of a
Soldier Termite.
NEW METHOD OF RADIO-MICROGRAPHY BY
P. GOBY. — A new and very attractive branch of science has
lately been opened up owing to the researches of a French
savant, and workers in various fields will now have a new
resource at their disposal, this being known as radio-micro-
graphy, as it is the application of the well-known principles of
radiography by the use of the X-rays to microscopic research.
While there has been a great improvement made in the
methods and instruments used for radio-
graphy of large specimens of ordinary
size, and remarkable results in the way of
radiographs are now obtained with such
apparatus, we are not aware that the struc-
ture of microscopic specimens has been as
yet revealed, so that the apparatus invented
by M. Pierre Goby, of Grasse, and the
radiographs which he secures by the use
of the rays, will be of interest to all naturalists. By observing
the views of the different specimens which we present in
Figures 401-405 on page 389, it will be
seen at once that the method is likely to be
a valuable auxiliary in all kinds of research
work, and the interior structure of the
specimens can in most cases be shown up
very clearly, as, for instance, in the case of
microscopic shells, diatoms, and the like.
Not only can the method be used for what
may be termed strictly microscopic
specimens, but it can also serve for en-
larged radiographs of very small animal
specimens, where an ordinary radiograph
would be too small to give the required
details.
In the account of his new method, which
M. Goby has kindly given to us, he states
that in both these cases the results are
obtained by the use of a special X-ray
apparatus of his design, and he expects to
make public the details of the device at a
not very distant date. Meanwhile he has
given us some radio-micrographs, as they
must no doubt be called, and they speak
for themselves. The details which he thus
obtains are difficult and in a great number
of cases impossible to obtain with the usual
method of sections prepared for microscopic
use. From the start, he commenced to apply his researches
in the field of palaeontology as well as in conchology, and
finds that the protozoa in general, as
well as foraminifera of all species and
other analagous microscopic specimens,
can be observed in their most minute
details in the interior of their structure,
and to show what can be done by the
new method we may state that he was
able to detect the presence of different
species in cases where ordinary exam-
ination would lead one to suppose that
only one species was present. In all
the sands which contain microscopic
specimens of different kinds such as
have not been examined, the use of a
fine pinch of sand allows of discovering
new species and to make a very exact determination of their
nature. The specimens which are illustrated here (see Figures
401 to 405) are magnified from twenty to twenty-five diameters.
One of them shows a pinch of sand from the south of France
(see Figure 404), containing a number of different forms.
Not less interesting is the application of the radiographic
method to very small animal specimens, and this allows us to
observe the gradual formation of the bones from the birth of
the animal to its full age. Not only can the details of the
bone structure be followed very clearly, but the method allows
of noticing the special features of the skin in many cases and
different anomalies — this with great precision in the details.
Figure 400.
Mandibles of
Termes bellicosus.
October, 1913.
KNOWLEDGE.
389
Figure 401. Nummulites.
Magnified 25 diameters.
Figure 403. An Orbitolite.
Magnified 25 diameters.
Figure 404. A pinch of sand from the
South of France. Magnified 20 diameters.
Figure 402. Fore and hind limbs of Seps.
Figure 405. Seps tridactylus.
390
KNOWLEDGE.
October, 1913
Figure 406. Halo obtained with X-rays without crystal.
Figure 409. Spots from mica normal to rays.
•
k
Figure 407. Halo from metals without crystals.
Figure 410. Reflection from mica at angle 85° showing
bands on the reflection and intermediate band.
Figure 408. No crystal used. Showing a broad white
band across plate ; also black bands.
Figure 411. Shows peripheral effects with mica across
aperture in metal screen.
October, 1913.
KNOWLEDGE.
391
Figure 412.
As will be observed in some of the illustrations, the flesh
parts and even the details of the muscles are apparent and are
clearly represented. It would be too long to enumerate the
applications which the new field of radio-micrography is
likely to obtain in the near future, but in furnishing the present
radiographs M. Goby is confident that scientific men will find it
valuable for different kinds of research work, and no doubt it
will be taken up in various quarters. Franc]s p> Mann_
Since the above was received M. Goby has described his
apparatus, and the following description is taken from a
translation of the contri-
bution to Compt es
Rendus, CLVI., pages
686-688, which appears
in the current number of
The Journal of the
Royal Microscopical
Society, from which
we have copied the
diagrams shown in
Figures 412 and 413.
The difficulty of obtain-
ing by the Rontgen rays
the requisite clearness of
detail has been overcome
by means of the appar-
atus shown in Figure 413,
which is carried on the
telescopic pillar u v, the
movable joint s of which
allows it to be pivoted
in a horizontal position.
Two large metal cylin-
ders a1, a2, the one sliding
within the other, form a photographic camera body, the
length of which can be varied as wanted. The top of this
body c is provided with a socket c1 through
which slides the axial metal tube d, which is
destined for suppression of the secondary or
superfluous rays, and for the transmission of the
cluster of active rays, which the thick leaden
diaphragm / of very small diameter allows to
pass, whilst a disc g opaque to the luminous rays
alone, shuts off other light which might affect the
photographic plate.
At the other extremity of the tube d an
" incidence indicator " or device for enabling the
incidence of the rays to be regulated is adapted,
which consists essentially of a very narrow
metallic tube i, supported by two discs h1, h",
permeable to the X-rays. Normally to this is
placed a small fluorescent screen /, which can
be examined through a darkened glass disc k,
destined to protect the eye of the operator,
when the apparatus is put in a horizontal
position. By means of the mechanism o, p, q,
the focus tube carrier I can be adjusted in two
directions, and all that is necessary is to adjust
the special Rontgen tubes held by the isolating
clamps m, m1, so that the small luminous spot
is seen in the centre of the screen surrounded by
a dark circle, thus indicating that the central ray of the cluster
is following a path axial to the tube itself. One can now
regulate the desired sizes of the radiographic field indicated by
the extent of the illuminated zone of the screen, by sliding the
tube d nearer or farther away from the source of radiation.
After once centring the focus-tube by means of the incidence
indicator, this does not need to be repeated, the indicator
being then slipped out of the tube d and laid aside.
All that now has to be done is, in the light of an ordinary
dark room, to place a small photographic plate, square by
preference and of very fine grain, on the centre of the leaden
disc 6, which forms the base of the camera, and which is
marked with a diametrical cross for purposes of registration.
The small object to be radiographed is placed in direct contact
with the sensitised surface of the plate without the interposi-
tion of black paper. It only remains to pull down the
cylindrical camera body into its grove and to allow the
appropriate rays of a Rontgen tube, with a very small anti-
cathode, to act for a convenient time in order to obtain, thanks
to the normality of the incident rays and to the suppression
of the paper envelope, the great clearness of detail which
allows of the radio-micrographs being enlarged to a consider-
able size.
PHOTOGRAPHY.
By Edgar Senior.
FAULTY PERSPECTIVE SEEN IN MANY
PHOTOGRAPHS. — Anyone who has compared a
photograph with the scene that it was intended to
represent must have noticed on many occasions
the great amount of difference existing between
the two with regard to the relative size of the
objects depicted when the photograph has been
taken with a short-focus lens. We have an
example before us as we write, taken with a lens
of this kind, in which the size of the objects in
the foreground is out of all proportion to those
at a distance, and this is by no means an isolated
example, but is quite a common effect obtained
by the use of wide-angle or short-focus lenses ;
and although wide-angle lenses are useful at
times, such as when working in confined situations,
there is the attendant disadvantage that objects
situated in the foreground are made to appear too
large compared with those at a distance. In con-
sidering the cause of this phenomenon, we must
remember that the eye when looking steadily at
an object forms an image upon the retina which embraces an
angle of not more than 60° ; therefore, in order that a
photograph may convey a
correct idea of the
relative size of the objects
represented when it is
viewed at a distance of
ten or twelve inches, the
angle included in the
picture should not be
greater than that of the
angle it subtends for
vision, which is from 55°
to 60° ; since if more is
included in the photo-
graph than this, the
images of objects in the
foreground will appear
too large in comparison
with those at a distance.
To render it obvious that
distortion of this nature
is not really due to any
fault of the lens, it is
only necessary to view
the photograph at a
distance equal to the
focus of the lens with which it was taken for the distortion to
disappear, or, better still, to enlarge the picture, as then it would
be viewed at a correspondingly greater distance. The conditions
under which a photograph will give a true representation of
natural objects have received considerable attention from Dr.
Alexander Gleichen, and in a paper translated by Dr. Lindsay
Johnson, M.A., F.R.P.S., and published in The Photographic
Journal, the author appears to consider that the aperture of
the lens should not in any case be larger in diameter than the
pupil of the eye (about eight millimetres), and that the focus
of the lens employed should not be less than ten inches (the
normal distance of distinct vision), or if the focus is less
than this the picture must be afterwards enlarged as many
times as the focus is less. Now, in using a ten-inch
^g^^^^^^^^K*^
Figure 413.
392
KNOWLEDGE.
October, 1913.
focus ens with an aperture of eight millimetres (1%) in
diameter, it is evident that the rapidity of the lens would be
equal to F/32, and this would be far too small for many
purposes. But as the size of the aperture is limited to is of
an inch in diameter, the only alternative is to use a shorter
focus lens, and so gain rapidity in that manner. Suppose, then,
that we wish to obtain a rapidity equal to an aperture of
F/6-4; then as the rapidity of lenses varies inversely as the
square of their focal lengths and the square of the diameter
of their apertures, the desired end would be gained by
reducing the focal length of the lens in the same proportion
as the diameter of the aperture would otherwise have to be
increased, which in this case is five times ; therefore, instead
of using a ten-inch focus lens, one of two-inch focus would
have to be employed ; and as 2 4- — = 6 • 4 we should gain the
rapidity while the size of the aperture itself remained
unaltered. At the same time the photograph would require
to be subsequently enlarged five times in order to be seen in
correct perspective when viewed at a distance of ten inches.
If the degree of enlargement to be finally obtained has been
previously decided upon, then the focal length of the lens
necessary for use in taking the original photograph " in order
that the required conditions may be fulfilled " can be found
from the following equation :
P-i
m
where F = the focal length of lens required, v = the distance
of distinct vision (ten inches), and in = the number of times
the picture is to be afterwards enlarged. Thus suppose that
the photograph is to be enlarged twice ; then
IT 10
r = — = 5 inches,
and as the diameter of the aperture is to be A-inch then
5 "J" r = 16, and the intensity ratio would be F/16. By trans-
posing the above equation we are also able to obtain the
distance from which the enlargement should be viewed.
v = F (m).
Thus suppose that a picture taken with the five-inch
focus lens is subsequently enlarged twelve times; then
v = 5 (12) = 60 inches, and the enlargement when viewed
from a distance of five feet should appear true to nature.
A SIMPLE FORM OF LENS SHADE.— It is obvious that
any light which reaches the plate, apart from that which is
actually employed in the formation of the image, must of
necessity have an adverse effect upon it ; and it is often found
when using a lens larger than is necessary to cover the plate
that the extra light which enters the camera, not being entirely
absorbed by the dead black with which its interior is coated,
causes a certain amount of haze or mistiness to appear over
the entire image, which destroys somewhat the brilliancy of
the picture. An effect of this kind is particularly noticeable
when working in an unusually bright light, such as that
obtained by the seashore, when something that will reduce
this excess of light becomes desirable. Adjustable hoods have
been recommended for attaching to the lens, but these are
difficult to manage, and whatever is employed, if it act in such
a manner that it only allows the lens just to illuminate the
plate that is in use, then the rising front is rendered useless, as
it is necessary for the circle of illumination to be considerably
larger than that required to include the plate to enable this
adjunct to a camera to be employed at all. The writer some
years ago made some experiments in bright light by the sea-
shore, to determine as far as possible the value of lens shades,
using a stand camera so that the various effects could be studied
visually as well as photographically, and the improvement that
resulted in both cases when a thin piece of wood made to
extend some four or five inches beyond the lens, and jointed
so that it could be depressed to any extent short of intercept-
ing the rays of light, was at once apparent. A shade of this
description was made that could be detached instantly from
the camera when not required, and as it folded up it was
easily carried in the pocket. Such an arrangement, however,
appears to be simply a modification of one used many years
ago by the late Mr. William England, and which is described
as a double-hinged mahogany flap which could be bent down
over the lens ; and from the very fact that it was found
valuable by this gentleman in taking the very fine photographs
which he produced should be an extra recommendation in its
favour. Then in the case of telephotography a shade in the
form of a hood becomes an absolute necessity for obtaining
brilliant pictures, since the amount of light which is actually
employed in the formation of the image is small compared
with that which enters the positive lens ; hence light traps in
the form of diaphragms inside the lens tube and special care
in the selection of a dead black and other devices are found
inadequate when dealing with an amount of stray light which
is many times greater than that used in taking the photograph.
On this account a tube or hood attached to the front of the
lens, and adjustable in length so that it can be altered to suit
various angles or magnifications, as suggested by Captain
Owen Wheeler, F.R.P.S., must be employed in cases of high
magnification in order to obtain the most brilliant images.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A., LL.D.
NEST MADE BY ORANG UTAN.— A recent issue
(Part I, 1913) of The Proceedings of the Zoological Society
of London, contains an interesting photograph, by Mr.
Seth-Smith, of the nest made in a tree near the Apes' House
by the large Sumatran Orang-Utan (Simia satyrus) which
escaped from its cage in November, 1912. It may be recalled
that a careful description has been given by Moebius of the
nests which the Orang makes in the woods. A nest is made
every night or every second night. It may be a yard and a
half long by four-fifths of a yard broad. It consists of two
dozen or so branches, with loose leaves above them. It is
simply a temporary bed and not, as some have asserted, either
a hut or a nursery.
A REMARKABLE FISH.— Messrs. Holt and Byrne have
described from the south-west coast of Ireland a new deep-water
fish (Lamprotoxus flagcllibarba) with several remarkable
features. The only specimen obtained had a body about seven
inches long, without including caudal fin and lower jaw.
It bore a filamentous barbel many times longer than the body.
The colour of the scaleless skin was velvety black, and the
barbel was grey. A purplish-grey cord-like band of luminous
tissue, partially embedded in the skin, formed a closed loop on
the anterior part of each side of the body. There was also a
large photophore behind and slightly below the eye, occluded
by skin save for a narrow slit. Very small photophores,
hardly visible externally, were present in lateral and marginal
series.
HERMAPHRODITE BEES.— In a hive in the Caucasus,
G. Kojewnikov found hermaphrodite bees. There were also
normal workers and drones from the same queen-mother.
The hermaphrodites looked like workers with the heads of
drones, but there was an intimate mixture of characters. One
of the mandibles was a drone's, the other a worker's ; the
eyes were drone's eyes, the thorax was a worker's thorax.
The sting was very variable. An interesting point is that
while some of the hermaphrodites had an ovary on one side
and a testis on the other, others had two ovaries or two testes.
Yet those which were unequivocally females or males as
regards the essential organs of generation were, nevertheless,
hermaphrodites in skeletal parts. This seems to show that
in this case the nature of the reproductive organs does not
influence the development of the external sex characters.
COMMENSALISM OF ANTS AND CATERPILLARS.
— Towards a hundred cases are known of caterpillars
(Lycaenidae and Erycinidae) living in commensalism with
ants. M. Charles Oberthiir has recently called attention
to two species in Brittany — Lycaena argiades and L. baton
— which appear to illustrate this kind of association. Harold
October, 1913.
KNOWLEDGE.
393
Powell reports the same in regard to L. baetica, L. bellargus
and L. iolas. An ant removed from its companion cater-
pillar (L. baetica) is restless and disturbed. In the case of
L. bellargus the ant rides on the caterpillar and caresses
it. Oberthur also refers to an Australian form which lives in
the nests of green ants. When the imago hatches out it is
covered with very deciduous white scales which fall like a
shower of confetti when it takes to wing from among its
quondam companions. There seems no doubt that this
association of ants and caterpillars will reward further
investigation.
LAND CRAYFISHES OF AUSTRALIA.— Very little is
known of the habits of these interesting animals (species of
Engaeus) which have left the aquatic habitat of their race
and become burrowers in damp ground. The burrows are
sometimes near the bank of a stream, but very frequently far
removed from any water in the middle of the forest in some
damp situation. There is water at the bottom of the burrow.
Messrs. G. W. Smith and E. H. J. Schuster, in a recent study
of the species of Engaeus, call attention to the great depth of
the carapace, its arched roof-like shape, the reduced
abdomen, the small eyes, and the tendency to reduction in
the size of the gills. An unusually strong hairiness of the
mouth-parts and neighbouring regions is probably correlated
with the necessity of filtering the water in the burrows, which
is usually very muddy. There are not a few minor losses or
suppressions, e.g., the loss of a flagellutn on the antennule
and the reduction of the antennary scale, and the authors
suggest that the underground burrowing habit which removes
the crayfis hes from active competition with other aquatic
forms has permitted degenerative changes which have no
special adaptive significance.
The young are brought into the world and tended by the
female parent in the same way as in the ordinary crayfish,
being carried about attached to the swimmerets. As the
animals keep to their burrows during the day, very little is
known as to their feeding habits. " It is probable that they
are mainly carnivorous in diet, as the remains of earthworms,
insect larvae, and probably land Crustacea have been found
in their stomachs The evergreen beech forests in
Western Tasmania support a very rich terrestrial fauna of
land amphipods (Talitrus) which swarm under the fallen •
beech leaves and timber, and numerous myriopods and insect
larvae occur as well, affording abundant food in exactly the
situations which Engaeus chooses for its burrows."
SPECIFICITY. — We have repeatedly referred in these
Notes to the existence of minute peculiarities of structure
which distinguish species, sometimes more convincingly and
reliably than do larger and more obvious features. A fish
may be known by a single scale or a bird by a single feather ;
and the cells lining the windpipe of a horse are readily
distinguished from those of the dog which barks at the horse's
feet. All flesh is not the same flesh, and nothing is more
specific than the blood. On a larger scale are peculiarities of
structure which run through a series of related forms. A
good example is furnished by Mr. Edwin S. Goodrich in his
study of the structure of bone in fishes. Ganoid scales are of
two kinds, which differ fundamentally in structure and mode
of growth — Cosmoid and true Ganoid. The latter are again
divisible into Palaeoniscoid and Lepidosteoid. The Lepidos-
teoid scale is easily distinguishable by the presence of a
system of delicate tubules running through and at right angles
to the bony layers. The same peculiar tubules occur in the
skull plates and other dermal plates of all the recent and
extinct Lepidosteoids and Amioids that have been examined,
with a single possible exception (probably a primitive form).
The minute peculiarity is quite distinctive. Mr. Goodrich
has more recently discovered that the Lepidosteoid structure
is exhibited not by the dermal bones only, but by the whole
endoskeleton as well. " The skull-bones, the ribs, even the
vertebral centra, are all provided with the characteristic
tubules traversing the bony lamellae, just as in the scales.
It follows that, from the examination of the minutest fragment
of the skeleton of a living or extinct species of fish, we can
decide whether or not it belongs to the Amioidei and
Lepidosteoidei, or to some other group. The histological
structure of the bone, may therefore be of the greatest
practical value for the identification of fragmentary specimens.
It may also prove of great importance in the interpretation of
phylogeny." This is a fine instance of a minute detail of
structure holding good as an index of relationship.
AFRICAN ELEMENT IN FRESHWATER FAUNA
OF BRITISH INDIA.— At the Zoological Congress at
Monaco Dr. Nelson Annandale directed attention to the
affinity, more close in some cases than in others, which can
be demonstrated between the freshwater fauna of India and
that of Tropical Africa. In some instances this affinity also
extends to South or Central America. The African element
in the Indian fauna was also compared with what we know to
exist in the fauna of the Jordan system. In the latter a large
contingent of the fish-fauna is pure African, but many of the
lower aquatic invertebrates resemble African forms much less
closely than do the Indian representatives of the groups. An
explanation may be found, on the one hand, in the more
recent date of the geographical connection between what is
now the valley of the Jordan and the river-systems of Africa ;
and, on the other hand, in the fact that existing conditions of
climate and chemical composition of the water are more
similar in Tropical Africa and India than they are in the
former and Palestine.
GALL-PRODUCTION.— Every contribution to the study
of galls is welcome ; for while great progress has been made
towards understanding them the uncertainties remain very
conspicuous. How far does the mechanical irritation pro-
duced by the parasite count as a stimulus ? Or is it wholly
chemical ? To what extent do bacteria and other fungi play
a part in stimulation ? How far is the gall that is formed in
response to the stimulus a quite new sort of growth ? How is
it that the same plant may produce several different galls in
response to the stimulus of not distantly related hosts ? How
far can it be held that the host derives benefit from the gall
because it thus restricts the sphere of the parasite's opera-
tions ? How far, on the other hand, is the plant playing into
the hands of its parasite by forming the gall ?
In a recent elaborate study of Canadian galls Mr. A.
Cosens maintains that the gall-producing stimulus renders the
protoplasm of the host more active and awakens in it
dormant characteristics, but does not endow it with power to
produce entirely new structures. The idea that the gall-pro-
ducing stimulus must be applied directly to the cambium is
not true in all cases, for any actively growing tissue will
respond to the gall-stimulus. Moreover the effect of the
stimulus is operative on tissue at a considerable distance from
the centre of application. There is no doubt that ferments
secreted by the gall-producer (Cynipidae) count for much.
They may pre-digest food for the larval gall-insect and may
indirectly stimulate cell- proliferation.
PERIWINKLES AND THE TIDE.— It has been noticed
that periwinkles (Littorina littorea) shift their position on
the rocks in correspondence with the tidal changes. It has
even been maintained that this tendency to periodic move-
ment is so engrained in the periwinkle's constitution that it
takes place apart from any tides. Recent experiments by
Haseman do not confirm the last statement. It seems, more-
over, that the oscillatory movements in normal conditions are
not exhibited by periwinkles on horizontal flat surfaces
between tide-marks or when they are below the low-tide mark.
What seems to remain secure is that periwinkles on the
vertical surfaces of rocks between tide-marks exhibit up and
down movements which correspond with the movements of the
tides.
MORE ABOUT BLACK TERMITES.— Professor Bugnion
has told us something more about Eutermes inonoceros, the
Black Termite of Ceylon. In their nocturnal excursions to
the trees — some of which were fifteen to twenty yards distant
— they usually managed to keep to the same paths. As they are
blind, they must feel or smell their way. Minute black specks
394
KNOWLEDGE.
October, 1913.
probably excrementitious, are often to be seen marking the
path. An interesting observation refers to a case where the
path followed went up four posts and down the other side
instead of keeping along the level ground 1
At critical places, or when danger threatens, the soldiers
form a double file guarding the march of the workers, and
they all face outwards. From an ampulla in their head they
squirt out viscous fluid in the face of offensive true ants like
Oecophylla. The nocturnal expeditions have the object of
collecting lichens, debris of leaves, and apparently some black
material from the humus.
HABITS OF THE AGAMA.— Dr. W. A. Lamborn gives
an interesting account of the habits of the common West
African lizard, Agama colonorum. There seems to be a
great disparity in the numbers of the sexes, and each male is
attended by several females, sometimes six or seven, who
behave with remarkable subservience towards their lord
and master. " The male's responsibilities seem to be in excess
of his capacities, so that the females are forced to resort to
various artifices to secure their share of his attentions." The
males are exceedingly combative, and the intrusion of one into
another's preserves usually leads to a battle. " The tail is the
offensive weapon, and to bring it into action the males take up
a position parallel to each other, but head to tail. Each seeks
to overcome the other, not by a number of strokes, but by a
single well-directed blow." The female lays the eggs, in a
cluster of three or four, in a burrow in the ground, and covers
them with earth. The lizards are usually insectivorous, but
will eat lettuce, tomatoes, and the like, in the dry season.
Their voracity is remarkable. On one occasion Dr. Lamborn
dropped no fewer than eighteen butterflies before a male
Agama, and all were consumed in ten minutes.
IN VERY DEEP WATERS.— Professor Louis Roule has
recently described a new abyssal fish, Grimaldichthys
profundissimus, gen. et sp. nov., which was dredged by His
Serene Highness the Prince of Monaco from a depth of
6,035 metres to the south-west of the Azores. One of the
features of this new form is that all the rays of the pectoral
fin are free and filamentous. The rather dangerous title
profundissimus indicates that up to date the depth inhabited
by this fish is greater than that recorded for any other.
HATCHING OF CROCODILES' EGGS.— Many years
ago (1899) Dr. Voeltzkow noticed that unhatched crocodiles
(Crocodilus madagascariensis) utter a cry from within the
egg — a cry that can be heard even when the eggs are covered,
as in nature, by one to two yards of sand. The sounds are
produced with the mouth closed, as we produce hiccough
sounds. Dr. Voeltzkow writes : — " This crying of the young
can be induced by walking heavily past the receptacle con-
taining the eggs (a box in the study), by knocking against it,
by taking an egg in the hand and turning it ; in fact, any shock
causes the young one to lift up its voice in the egg. As the
female visits the nest almost daily in order to convince herself
of its orderly condition, her passage from the water to the
nest and back shakes the ground and induces the production
of sound by those young ones which are sufficiently developed.
Thereupon the old one scrapes the sand out of the pit and
presently the young emerge." Dr. W. A. Lamborn has
recently made similar observations in regard to Crocodilus
niloticus at Lagos. Croaking noises were heard from below
a dry path, and when he dug down he found thirteen eggs, all
chipped save a bad one, at a depth of about eighteen inches.
All the young crocodiles hatched out within half an hour of
being dug up.
SOLAR DISTURBANCES DURING AUGUST, 1913.
By FRANK C. DENNETT.
August has been marked by a continued absence of
activity on the Solar disc. On two days only (11th and 28th)
tiny spotlets or pores were visible, on eight others (10, 14,
16-19, 27 and 29) faculae were seen, and on the remaining
twenty-one days the sun appeared free from disturbance,
unless exception be taken to a greyish patch some thirty
hours past the central meridian, in north latitude, seen on the
24th. The longtitude of the central meridian at noon on
August 1st was 87° 10'.
By some strange mishap the spot groups and faculae for
July have not reproduced on the diagram in the September
number of Knowledge ; they have therefore been inserted in
our present chart, the faculae being distinguished by the
letter a.
On August 11th a tiny pore was visible, amid faculae,
advancing from the north-eastern limb ; it was too minute for
measurement, but was approximately in the position marked
by a cross in longitude 248°, N. latitude 10°. Only seen on
one day.
On the 28th a minute pore with faculae was seen some
40° round the eastern limb — approximately in longitude 40° —
cloud intervened before exact measurements could be made.
Faculae were visible on the 10th some 35° from the south-
western limb. On the 14th a small double facula, situated
just south of the area of Group No. 9, closing up to the
western limb. On the 16th a small bright cloud seen less
than 20° from the North Pole, some three days past the
meridian. On the 17th and two following days a facula seen
some 8° S. latitude, in longitude 155°. On the 27th a tiny
facula was almost on the meridian about 18° from the South
pole ; also a brilliant knot in N. latitude 34°, longitude 21° ; this
remained visible ou the two following days.
Our chart is constructed from the combined observations
of Messrs. J. McHarg, E. E. Peacock, and F. C. Dennett.
DAY OF AUGUST, 1913.
7
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5
4
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f, f
1.
28
1
tt
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tf
If
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V'
'?
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f
16
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It
n
a
11
1
|
y
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5
0
sa
0
11
'■y
ot
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so
N
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fc:>
1
0
9
0
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31
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u
5
a
71
8
) 91
) u
0 II
i k
0 K
0 K
0 I
0 K
0 u
0 IE
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0 2
It I
i 2
t :
0 i
0 ?
0 ?
V 2
t I
to Z
"0 I
X 5
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0 3
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0 H
0
October, 1913.
KNOWLEDGE.
395
Hy the co-atesy of
Figure 414.
Male Peregrine Falcon or Tiercel.
(From "The Peregrine Falcon at the Eyrie.")
Country Life, Ltd,
396
KNOWLEDGE.
October, 1913.
Figure 415.
An Archegonium of a fern.
Figure 416.
A Prothallium of a fern.
Figure 417.
An Antheridimn of a fern.
m
* r4mc^4lh^ 4 ♦
Figure 418. The Sparassis (Sparassis crispa).
A fungus (one-half natural size) covered with twisted, thin, brittle lobes of a creamy white tint, found only in pine-woods, and
considered to be one of the most desirable of the esculent species.
(From "Hutchinson's Popular Botany," by the courtesy of Messrs. Hutchinson & Co.)
REVIEWS.
BIOLOGY.
La Biologic Synthetique. — By Professor Stephane Leduc.
217 pages. 118 figures. 9-in. X5^-in.
(Paris : A. Poinat. Price 6 francs.)
This is a sequel to the author's Theorie Physico-
Chimique de la Vie et Generations Spontanees, translated
by Dr. Deane Butcher and published under the title of The
Mechanism of Life (Rebman, 1911). Professor Leduc
points out that hitherto life has only been studied analytically ;
that is to say, living organisms have been investigated by
studying in detail each separate part. He suggests that it is
time the synthetic method be applied in biology, since many of
the phenomena associated with living organisms are exhibited
(or, perhaps one would say, simulated) separately in the
inorganic world. The book is highly suggestive, and the pro-
posed synthetic method of dealing with biological problems
ought to prove of great value. The book is marred, however,
by a tendency to materialistic metaphysics — a domain which
in reality lies outside of pure science. What Professor
Leduc terms " physicisme " and " mysticisme " are comple-
mentary rather than antagonistic. Philosophy completes the
work of science. The latter is concerned with the correlation
of phenomena ; the former seeks their source. The latter
may adopt a mechanistic theory of life ; the former must
transcend this.
H. S. Redgrove.
BOTANY.
Hutchinson's Popular Botany. — By A. E. Knight and
Edward Step, F.L.S. Vols. I and II. 588 pages. 721
figures. 18 coloured plates. 10-in. X 7-in.
(Hutchinson & Co. Price 7/6 each Vol. net.)
There was a time, and that not very long ago, when the
study of Botany meant to a very large extent the mere
collecting and naming of flowering plants. Hutchinson's
" Popular Botany " shows well how things have changed.
The inside of plants to many has become more interesting
than specific differences. The way in which the various
parts do their work and still more recently the interrelation
between plants which form communities and the connection
between plants and animals have attracted wide attention.
All these topics as well as those groups of plants which
do not bear flowers are considered and illustrated in " Popular
Botany " by a wealth of photographs and careful drawings,
the latter by Mr. A. E. Knight and the former, in many cases,
by Mr. Edward Step. There are also eighteen coloured
plates. The first volume contains chapters dealing with the
cell, with tissues, with physiological processes, with structure,
and lastly with the leaf in relation to environment. In the
second volume the last-mentioned topic is completed, floral
forms and their relations to insects are discussed at length,
and the reproduction of flowering plants and lower forms is
described and illustrated. Examples of the pictures, which
are a great feature of the book, we are permitted to give on
Page 396.
W. M. W.
CHEMISTRY.
Mineral and Aerated Waters. — By C. Ainsworth
Mitchell. 227 pages. 114 illustrations. 83-in. X54-in.
(Constable & Co. Price 8/6 net.)
From very early times the waters of certain springs and
wells were supposed to have medicinal properties which were
generally considered to be supernatural or miraculous. As
the chemists of the eighteenth and early nineteenth centuries
acquired a knowledge of the constituents to which the
therapeutic effects were due, it was natural that attempts to
prepare them artificially should be made. In this book the
author gives a short account of spas, wells, and natural
mineral waters, and then traces historically the development
of aerated water manufacture from Bergmann's primitive
efforts to the complicated methods of the present time. The
latter involve not only the use of liquid carbon dioxide and
elaborate machinery for aeration, but also ingenious
mechanical methods of purification and bottling.
An excellent description of these processes, accompanied by
many valuable diagrams and photographs, occupies a great
part of the book. The chapter on the bacteriological and
chemical examination of the manufactured products is
interesting, but we think that, in view of the fact that the
amount of lead in citric and tartaric acids has not reached the
minimum suggested by analysts, some of the common tests for
this metal might have been included. The work of Bardet has
shown lately that though lead, tin and silver are generally
constituents of well waters, they are only present in spectro-
scopic amounts, so that the acids and essences — which, by the
way, are scarcely mentioned in the book — are probably the
only sources of impurities. The bibliography might have
included, with advantage, such works as Raspe's " Heilquellen
Analysen " and the " Deutsches Baderbuch."
These omissions however, do not detract from the merits
of an excellent book, which is not only extremely interesting
to the general reader, but should prove most useful to the
manufacturer. . „ T
A. S. Jr.
Treatise on General and Industrial Organic Chemistry.
— By Dr. E. Molinari. Translated from the Italian by
T. H. Pope, B.Sc, F.I.C. 770 pages. 506 illustrations.
(J. & A. Churchill. Price 24/- net.)
This volume is practically a continuation of the author's
work on Industrial Inorganic Chemistry which was recently
reviewed in these columns, and deals with the subject upon
similar lines. The first part gives a general outline of the
physical and chemical methods of examining and identifying
organic compounds, and includes sections upon elementary
analysis, determination of molecular weights, and the relation-
ship between physical properties and chemical constitution.
• Part II gives an account of methane and its derivatives, and
includes hydrocarbons, fats, alcohols, and sugars ; while Part
III. deals with cyclic compounds, including aromatic hydro-
carbons, phenols, colouring matters, proteins, glucosides and
so on. In the case of each group of compounds, a general
outline is given of the characteristics of the principal
individuals, and this is followed by an account of industrial
methods of preparing those of technical importance. For
example, twenty pages are devoted to the description of the
manufacture and purification of illuminating gas, and a similar
space to petroleum and its products.
The author's aim appears to have been not so much to give
exact details of experimental work as to enable the reader
to follow the principles upon which the industrial processes
are based.
Dealing with such a wide range of subjects, it was obviously
impossible for one man to be thoroughly conversant with
them all, and in certain places this want of first-hand
knowledge is manifest. Taken as a whole, however, and
judged by those sections with which the reviewer is most
familiar, the book may be recommended as accurate and
up-to-date. Here and there small errors and inaccuracies
may be noted. For example, it is not correct to state that
" in comparison with all other fats, butter contains a large
quantity of volatile acids soluble in water." Possibly, how-
ever, it is the translation that is at fault here, and the reading
should be " a larger quantity than any other fat." The slip
on page 281 where it is stated that "the most favourable
temperature is 30 per cent. " makes the passage meaningless.
If "30°C." is meant, the statement is not borne out by the
facts.
The book is profusely illustrated, but it is to be regretted
that worn electros have been used for many of the illustrations.
397
398
KNOWLEDGE.
October, 1913.
In the future edition, which is sure to be needed before long,
it would be advisable to replace many of these blocks by
fresh drawings. The work deserves it.
C. A. M.
GEOLOGY.
Volcanoes, their Structure and Significance.- — By Professor
T. G. Bonney, Sc.D., LL.D., F.R.S. Third Edition.
379 pages. 16 plates. 21 illustrations. 8£-in. X6-in.
(John Murray. Price 6/- net.)
Since the second edition of this work much has been added
to our knowledge of vulcanicity by the great eruptions of the
Soufriere and Mont Pelfee, and by those in Guatemala and
Savaii. The first-named, however, was treated in an appendix
to the second edition, but in this book it assumes its proper
place in the text as, in at least one feature, a new type of
vulcanicity. The book is divided into six chapters, each
elaborating one aspect of volcanoes, their life history,
products, dissection, geological history in Britain, distribution,
and origin. The book is written in a picturesque and vigorous
style, well adapted to sustain the interest of the general
reader for whom it is intended. A disarming preface wards off
undue criticism. We may perhaps observe that while the
simplified petrographical nomenclature adopted may be very
comforting to both author and reader there is no such
simplicity in the rocks themselves ; and although the author
animadverts on the great number of new names, the majority
of them are absolutely necessary if any serious comparative
work in petrology is to be done. Professor Bonney also
favours the older view that there were two periods of eruption
in the famous old volcano of Arthur's Seat, Edinburgh ; but
the recent detailed mapping of the Scottish Geological Survey
is decisive in favour of Professor Judd's view that it is the
product of one continuous volcanic episode. The book con-
cludes with an admirable chapter on the various theories
advanced to account for volcanoes, in which we should have
liked to have seen some reference to Daly's recent fine work
on the mechanism of volcanic action. „ ... ~
g. w. r.
Submerged Forests. — By Clement Reid, F.R.S. (Cambridge
Manuals). 129 pages. 5 figures. 6£-in. X 5-in.
(The Cambridge University Press. Price 1/-)
At many places around the English coast black peaty earth,
with tree-stumps and other plant-remains, is exposed between
tide-marks. Several layers of this material, the lowest
generally at a depth of sixty feet below sea-level, are often
found in dock excavations. These submerged forests,
although, as explained by the author, muddy subjects to
dabble in, are replete with scientific interest, and their
exposition has given rise to a most interesting little volume.
Submerged forests and their correlatives, raised beaches, give
the clues to the most recent vicissitudes in the relative levels
of land and sea. According to the author's estimate the
submerged forests indicate a recent subsidence of nearly
ninety feet of the land with respect to the sea. The newest
of these deposits belongs to the age of polished stone, and the
earliest also probably comes within the Neolithic period. In
Mr. Reid's opinion the earth-movements ceased about three
thousand five hundred years ago, and began about one
thousand five hundred years earlier. These estimates, as we
are carefully told, are not to be taken as exact, since they are
based on somewhat uncertain factors.
Most of the book is occupied with the description of the
submerged forests seen on the English coasts. Amongst the
interesting subjects dealt with, the Dogger Bank, and the
question as to the mode and date of the severance of Britain
from the Continent, are the most likely to appeal to the
general reader. The author is to be congratulated on this
fine exposition of what, at first sight, appears to be an
unpromising and difficult subject.
G. W. T.
HISTORY.
Ancient Greece. — By H. B. Cotterill, M.A. 498 pages.
12 plates. 4 maps. 141 illustrations. 8^-in.X 5i-in.
(George Harrap & Co. Price 7/6 net.)
In an agreeable and compendious volume Mr. Cotterell has
furnished a popular history of Ancient Greece from the
earliest times about which anything is known down to the
life of Alexander the Great. He has interwoven with it
some account of Greek philosophy, literature, and art, and
added copious illustrations of sculpture, vases, ancient sites,
and famous men. The book will be a boon to the general
reader, who, with no knowledge of the Greek language and no
inclination for laborious study, would gladly acquaint himself
with the meaning and the place in history of all that is most
beautiful and expressive in art. The book, in fact, supplies a
want that must often have been felt by intelligent people with
small leisure. Mr. Cotterill sketches briefly the results of
recent discoveries throwing light on Aegean civilisation, and
shows how the early history of Greece was connected with
that of Crete and Egypt ; facts made additionally clear by a
useful chronological table, which provides an approximate
idea of their contemporary histories. In later times that most
tragic and graphic chapter in Greek history, the Sicilian
expedition, is illustrated by quotations from Thucydides ; the
march of the ten thousand from Xenophon. Mr. Cotterill
writes with a keen appreciation of what he describes and the
illustrations, to which allusion has already been made, have
been judiciously selected and well reproduced. Even coins
have received attention in this pleasant and useful book.
E. S. G.
PHYSIOLOGY.
Laws of Sexual Philosophy. — By J. L. Chundra. 208
pages. Frontispiece. 7i-in. X 5-in.
(Calcutta : The Author. Price 4/- net.)
Dr. Chundra is Professor of Medicine in the National
College of Calcutta, and his book is designed for students
of gynaecology and obstetrics. The volume contains much
that is of physiological and medical interest. Among other
points it discusses the theories which have been brought
forward and the experimental investigations, for instance of
Professor Schenck, with regard to the determination of sex.
The chapter entitled " The Laws of Genius," in which the
question of influence transmitted by parents to their children
is discussed, will hardly at the present time obtain serious
consideration.
W. M. W.
POLITICAL ECONOMY.
The Fate of Empires. Being an Inquiry into the Stability
of Civilisation. — By Arthur John Hubbard, M.D.
(Dunelm.) 220 pages. 3 figures. 8J-in. X5J-in.
(Longmans, Green & Co. Price 6/6 net.)
Dr. Hubbard has an interesting thesis to maintain. He
attempts to discover those forces which make for the growth
and decay of civilisation and of which history gives us only
the resultant. Of the latter he holds there are two, namely,
those due respectively from the social stress (i.e., the
competition of one's fellows) and the racial stress (i.e., the
trials and troubles of parenthood). Every stage in the history
of organic advance, he argues, will be found to be governed by
a new method or idea whereby life can be maintained on a
high scale. Each new method is superimposed upon the old,
which is utilised, not discarded, by the new. These methods
are as follows : — (1) Reflex Action ; (2) Instinct ; (3) Reason ;
(4) Religious motive. Instinct sacrifices the individual to the
race ; Reason, which results in Socialism, Dr. Hubbard
maintains, sacrifices the race to society, whose interests under
such a regime are identical with those of the individual. In
support of this he contends that Socialism appears simul-
taneously with a fall in the birth-rate. The method of
religious motive, he contends, alone reconciles the interests
of individual, society, and race by raising conduct from
geocentric to cosmocentric significance.
October, 1913.
KNOWLEDGE.
399
I am inclined to think that Dr. Hubbard has fallen into the
error of identifying reason with selfishness. Pure reason is
motiveless; it is an organon which any desire may utilise to
gain its ends ; and for this reason Dr. Hubbard's enumeration
of the methods of organic progress seems hardly satisfactory.
Nor is there any reason why Socialism should result in a falling
birth-rate; the instinct to propagate one's species (to look at
the question from a purely selfish standpoint) is, on the whole,
sufficiently strong to counteract the desire for ease and
comfort ; and whilst one can thoroughly agree with Dr.
Hubbard's appreciation of the method of religious motive it
is difficult to see how any system of political economy could be
constructed on this basis. The State can compel its members
to obey laws constructed by the aid of reason for their own
benefit ; it cannot compel them to be religious, though much
can be done by means of education. The theoretical portion
of Dr. Hubbard's book is followed by an historical section in
which his views are illustrated by reference mainly to the
Roman and Chinese civilisations. The account of the latter is
particularly interesting and suggestive.
H. S. REDGROVE.
SPORT.
The Tarn — the Lake. — By C. J. Holmes.
8i-in.X5i-in.
48 pages.
(Philip Lee Warner. Price 2/6 net.)
" The Tarn — the Lake " appears to be a prettily written and
imaginative treatise on fishing, but after the first two chapters
Mr. Holmes switches the giddy and bewildered reader on to
the Italian Renaissance, and proceeds to discourse on
" Shoes and Ships and Sealing-wax." Not that his observations
on these and kindred subjects are wholly lacking in suggestivc-
ness, but it is such a far cry from reminiscences of his youth-
ful experiences with minnows, and he takes so much for
granted, and he asks so many questions and never waits for
an answer. But eventually he deduces to his own satisfaction the
conclusion that degeneracy overtakes men and fish alike, when
all the natural incentives to healthy exertion are too carefully
removed.
E. S. G.
ZOOLOGY.
An Introduction to Zoology. — By Rosalie Lulham, B.Sc.
457 pages. 6 plates. 328 figures. 7-2-in. X 5-in.
(Macmillan & Co. Price 7/6.)
Miss Lulham has such a reputation in connection with
Nature Study work that one would expect any book that she
might write to be interesting and original. We are not
disappointed with the present volume, and it is evident that
much of the information included is culled from the writer's own
observations. If the classifications given are not always those
which have been based on recent researches it may be that
the author has in mind those who wish to classify things more
particularly in the field. For instance, the dragon flies with
no complete metamorphoses are still placed in the order
Neuroptera with such forms as the lace-wing fly, where there
is a resting stage. The reason suggested can, however, hardly
explain why the Testacellidae, which contains the worm-eating
slugs, the most highly modified of all land mollusca, is not put at
the head of the Stylommatophora, and from the description
also it is not evident that forms with well-developed shells are
placed in the family. Any little points of this kind are, how-
ever, over and again made up for by the practical notes given
at the end of each chapter, and we may mention specially
those on ants and the keeping of ants' nests. There are also
many useful hints and references given of the greatest value
to young students. In fact, the book is intended to take
the place of ordinary notes for those whose teachers spend
most of the time at their disposal, as should be done, in
practical work. w M w
The Peregrine Falcon at the Eyrie. — By Francis
Heatherley, F.R.C.S. 78pages. 30 illustrations. 11-in.by
8-in.
(" Country Life." Price 5/- net.)
Mr. Francis Heatherley is a bird-lover with a knowledge of
photography who during three seasons has carefully watched
the eyrie of the peregrine falcon, and the book under
consideration contains the records of his own and his friends'
observations. The author says that what little experience he
has had of the official ornithologist makes him anxious not to
be confounded with the latter, as the present mania for bird
and egg collecting is deplorable, considering the difficulties it
places in the way of study when so much remains to be
learnt of the habits of living birds. Mr. Heatherley has
also no exaggerated veneration for the printed word which he
too often finds is copied from one text-book to another in de-
fault of original observations, and in the case of the peregrines,
his only working hypothesis was that the falcon is bigger than
the tiercel.
Among the chief points of interest brought out are the time
of incubation and the way in which, after a few days, the
falcon handed over to her mate the actual*work of feeding the
young and looking after them while she spent her time in
hunting and bringing the quarry to him. On one occasion the
hen bird absented herself for a considerable time, and Mr.
Heatherley is doubtful whether she did this voluntarily, owing
to the constant presence of strangers, or whether she had been
shot, and the tiercel managed to secure the services of another
falcon. It would be interesting to know whether, if he had
been left to himself, the male bird would in the end have been
driven to hunt to appease his hunger, and that he would after-
wards have fed the young. It appears that the prey that was
brought to the nest for the latter was plucked or not according
to the time which the falcon had at her disposal. What she
brought for the tiercel's own consumption was usually skinned.
The young ones paid more attention to the warning note of
their father than that of their mother, and it is curious that
when they began to take their food with less alacrity the
tiercel encouraged them by giving a sharp yap.
Mr. Heatherley has come to the conclusion that the
difference in size between the nestlings is a sexual one, and
.not dependent upon the fact that incubation starts with the
first laid egg. Mr. C. J. King, who visited the eyrie in 1913,
found that of the three eggs one was larger than the others
and weighed fifty-eight grains more, while the difference
between the two small eggs was not more than a grain. Of
the peregrine language the author only learnt three phrases,
but he says that the use of a hiding contrivance greatly
enlarges one's appreciation of bird language — a rich field
for investigation. " In raising himself from the wild, man
has cut himself off from much knowledge of the ways of
his poor relations, knowledge some of which even our
immediate ancestors retained ; for instance, the use of the
great grey shike as sentinel by the Dutch trappers of passage
hawks, a use of a bird's characteristic implying an intimate
knowledge few museum authorities would care to claim.
Modern bird-photography and nature study are, however,
again lifting the veil."
In concluding his very original and interesting book, which
we recommend most heartily to all lovers of birds, Mr.
Heatherley gives some details with regard to his photo-
graphic work. He uses a lens with a fifteen-inch focus
because he sees no sense in going to the trouble of getting
the camera within six feet of a shy bird and then being
content with an image the size of a postage stamp. With
Kearton, he believes in developing some, at any rate, of his
exposures at the end of the day. He has three shutters
to his camera : (1) a time and instantaneous one fastened on to
the front, (2) a silent studio shutter which he can fix on by
taking out the back of the camera, and (3) the most expensive
and the least useful — a focal plane shutter at the back. He
uses a blackened brass cylindrical hood to screw on the lens in
front so as to project two or three inches, which proves useful
against sun and rain. He finds a rucksack the most con-
venient means for transporting apparatus, and the safest,
400
KNOWLEDGE.
October, 1913.
because a heavy bag swung over the shoulder is likely to
suddenly shift when you are in some awkward situation
and shake your nerve, if it does nothing worse.
By the courtesy of the publishers we are able to reproduce
on page 395 one of the many excellent photographs with
which the book is illustrated. ... ,, ,,,
W. M. W.
A Dictionary of English and Folk-Names of British
Birds. — By H. Kirke Swann. 266 pages. 8f-in. X5f-in.
(Witherby & Co. Price 10/- net.)
In this list the accepted English names of British birds are
printed in capitals throughout, and under the principal
headings there is given much folk-lore and many legends
with regard to the more familiar species. Some of the stories
are very curious ; for instance, the popular belief about the
song-thrush is to the effect that the bird acquires new legs
and casts the old ones when about ten years old. Another
notion, which comes from the Border, with regard to the pied
wagtail is that it ought always to wag its tail nine times on
alighting and before beginning to run about or feed, and
should the number be less or more it is very unlucky for the
person who is counting. More important from an ornitho-
logical point of view is the fact that Mr. Swann gives a
reference to the first usage of the various names. Altogether
there are nearly five thousand names of all kinds gleaned
from literature, from county lists, from several languages
and many dialects, and it is obvious that to bring them
together, quite apart from the many interesting details that
have been added, must have entailed a prodigious amount of
work. The time is gone by when the labours of the compiler
were not properly recognised, and the value of Mr. Swann's
book to all writers upon and students of birds will be acknow-
ledged as very great. W. M. W.
NOTICES.
ALEXANDER AGASSIZ.— Messrs. Constable will publish
almost immediately the " Life and Letters of Alexander
Agassiz," edited by his son.
THE FOX. — Mr. J. C. Tregarthen's " Life Story of a Fox,"
which has gained the admiration of many nature-lovers by
the accuracy of its observation and its charming style, is
shortly to be issued in a cheaper form by Messrs. A. & C. Black.
THE CENTURY MAGAZINE— In the issue of this
magazine for September, Mr. Robert Sterling Yar,d, the new
editor, reviews the aims of the magazine in the past, and sets
forth what they will be in the future. We wish him every
success.
UNKNOWN SOUTH AMERICA.— Mr. A. Henry Savage-
Landor has been for the past seven months hard at work on
his new book, "Across Unknown South America," describing
his remarkable journey across that beautiful and virgin
continent. The book is now completed and will be published
shortly, in two volumes, by Messrs. Hodder & Stoughton.
A NEW NATURAL HISTORY.— For many years Messrs.
Cassell have specialised in Nature-study volumes, and the
latest addition to their series of books upon this subject
will be ''Cassell's Natural History," which will deal with all
the latest discoveries in Nature Science, and contain photo-
graphs taken direct from Nature in natural colours, as well as
an abundance of other photographs.
THE NEW ENCYCLOPAEDIA.— Messrs. T. C. and
E. C. Jack announce the publication of a new encyclopaedia.
The work will be original throughout, and owing to the way in
which the matter is condensed and the illustrations treated,
the one thousand six hundred pages will contain as much
information as is usually put into six large volumes. All the
entries are thoroughly up to the latest date, and science is a
strong feature of the work. Struck by the inconvenience to
the reader of having from a dozen to twenty volumes to choose
from, and the consequent confusion and irritation, the
publishers have put the whole into one good-sized volume. A
large edition has been printed, and the work will be issued at
a popular price.
MACMILLAN'S NEW BOOKS.— From the classified list
of announcements of new books which Messrs. Macmillan
and Company have issued, we find quite a number dealing
with anthropology and archaeology. Among these are the
two parts of " The Golden Bough," which will complete the
third edition of Professor Frazer's great work. In " Marriage
Ceremonies in Morocco " Professor Westermarck repairs the
omission of which he says he was guilty when he wrote " The
History of Human Marriage" more than twenty years ago.
We notice also that the first volume of an English edition of
Windelband and Ruge's " Encyclopaedia of the Philosophical
Sciences " is being brought out under the editorship of Sir
Henry Jones. There are besides a number of scientific books
which should be of interest to our readers.
BIRKBECK COLLEGE.— We have received the Calendar
of the Birkbeck College for 1913-14. Founded by Dr. George
Birkbeck in 1823, this institution has played a very great part
in the education of the Metropolis, and is now conducted in
relation with the University of London. Classes are held both
in the day and evening ; thirty-two members of the staff are
recognised teachers of the University.
The courses of study provide for Degrees in the Faculties of
Arts, Science, Laws, and Economics.
In Science there is a very extended curriculum for
Chemistry, Physics, Mathematics, Botany, Zoology, and
Geology. The laboratories are well equipped with modern
apparatus and appliances, and research work is carried on in
all the departments.
The 91st Session of the College commenced on Monday,
29th September, when the Opening Address was given in the
Theatre, at 7 p.m., by Sir Francis Darwin, F.R.S., LL.D., D.Sc.
ARTIFICIAL FERTILISATION.— Dr. Jacques Loeb,
head of the department of Experimental Biology in the
Rockefeller Institute for Medical Research, has written a
companion work to his " Mechanistic Conception of Life,"
which attracted much attention on its publication last year,
entitled " Artificial Parthenogenesis and Fertilisation." It
will be issued during the autumn by the Cambridge
University Press, as British agents for the University of
Chicago Press. The subject of the book is an analysis of the
mechanism by which the male sex cell, the spermatozoon,
causes the animal egg to develop. The author has gained a
world-wide reputation for his achievements in artificial
fertilisation, and this work penetrates, in great measure, the
mystery which surrounds the term " life " to the extent of
showing how the action of well-known chemical and physical
agencies may be substituted for that of the mysterious
complex called the " living spermatozoon."
ELEMENTARY STUDIES IN ASTROSPECTRA.—
In November, Professor Bickerton will commence in " Know-
ledge " a series of articles on stellar spectroscopy for
beginners. These articles although intended for persons having
no knowledge of spectrum analysis, will by simple basic steps
lead the student to the solution of problems that eminent
astronomers admit themselves unable to explain. They may
therefore be useful to all interested in stellar spectra or in
the making and reading of even complex spectrograms. By
the term " spectrogram " is generally understood a photograph
of a celestial object taken by means of a telescope or camera
armed with a prism or diffraction grating.
Professor Bickerton has been for many years in New
Zealand, where he held a chair in experimental science for
over a quarter of a century. The Chairman of the Board of
Governors of his College, writing in the New Zealand
Spectator, of which he is editor, says : — " Professor Bickerton
is a man of intellectual power, a most picturesque writer,
and above all one who can invest scientific subjects with a
literary charm that makes them intensely interesting to the
lay mind."
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
NOVEMBER, 1913.
THE ESTABLISHMENT OF A RACE OF WHITE
CANARIES.
By MAUD S. MARTIN.
Some white canaries were exhibited before the
Linnean Society, in the year 1912, and the following
is an account of how the race was obtained, by Mrsi
Martin, who bred them. Professor Arthur Dendy,
F.R.S., who introduced the exhibit, has kindly
written the following lines by way of preface to
the article.
Last year I had the pleasure of meeting Dr. Palmer,
of New Zealand, who had brought over to England
a considerable number of white canaries bred by
Mrs. Martin. At my suggestion Dr. Palmer exhibited
a pair of these very beautiful birds at a meeting of
the Linnean Society, where they aroused great
interest, and in response to a request for further
information as to how they had been obtained,
Mrs. Martin has very kindly written the following
account, which I feel sure will be welcomed by
readers of " KNOWLEDGE." " Mendelism " is so
much to the front nowadays that it is hardly necessary
to point out the great interest of Mrs. Martin's
observations. They afford an excellent illustration
of the wonderful power which the scientific study of
heredity has placed at the disposal of those who
wish to produce new and permanent varieties of
plants or animals. White canaries have, it is true,
occasionally been obtained as sports by previous
breeders, but I believe I am right in saying that no
one has hitherto succeeded in establishing a pure
white breed. That this has now been accomplished
by an amateur, working alone in New Zealand, and
without any special scientific training, shows how
much may be expected in the future from the
application of Mendelian principles. Thanks to such
writers as Professor Bateson and Professor Punnett —
to mention only two of the best known workers in
this field — a knowledge of these principles is now
widely disseminated, and Mrs. Martin's work illus-
trates very clearly how easily and successfully such
knowledge can be put to practical use.
Mrs. Martin is, of course, responsible not only
for the results obtained, but also for the form
in which those results are set forth ; but in justice
to her it should be stated that, being in New Zealand,
she has had no opportunity either of consulting with
specialists in the subject or of revising the proofs of
her paper. . D
During the season of 1908-9, a pure white hen
canary (having a grey tick on the left cheek) was
hatched in Martinborough, Wellington, New Zealand,
being a sport from ordinary buff parents — its mother
being a buff hen with a black cap, and its father a
buff cock with a green crest and green wing mark.
In the same nest as the white sport were three other
birds, all buffs, more or less marked with green. All
the birds in this aviary were very much in-bred, and
many of them were very pale in colour, being a
creamy white in the nest feathers, but moulting
401
402
KNOWLEDGE.
November, 1913.
brighter. One very pale cock bird (with a grey tick
of the left cheek) was mate to most of the hens
both young and old.
The parent birds escaped after rearing their
brood.
The white sport hen was bred by Miss Lee, of
Martinborough, and I purchased it from her, as I
intended, if possible, to produce from it a race of
white canaries breeding true to colour. To attain
this end I determined to experiment on Mendel's
lines and bought as a mate for the white sport a buff
cock, quite unrelated to her. From the mating of
generation) I mated in 1911-12 to their sons the
white cocks of 1910-11 (second generation) and
from them I obtained fourteen buff chicks and
twenty-six white chicks (see Table 75).
The three white hens (1910-11, second generation)
I mated to white cocks (1910-11, second genera-
tion) in 1911-12, and from them I obtained twenty-
five white chicks, no buff ones appearing in the nests
at all, apparently proving their recessive character
(see Table 76). The six buff hens (1910-11,
second generation, I mated to white cocks (1910-11,
second generation) in 1911-12. Two of them gave me
2 buff hens.
Mated to a white
cock.
All buff chicks.
No whites.
Evidently pure
Dominants.
Table 72.
Buff cock, 1908-9. X Pure white sport hen.* 1908-9.
(Black Cap.) (Grey tick on left cheek.)
3 buff cocks.
(Clear and variegated.)
4 buff hens.
Mated to white
cocks.
Some white chicks.
Some buff chicks.
Evidently impure
Dominants or hybrids.
3 buff hens.
(Clear and variegated.)
9 white birds.
6 cocks and 3 hens.
3 cocks X 3 hens.
25 white chicks.
No buffs.
Evidently recessives
and breeding pure.
Several buff cocks.
Not used again for breeding.
1st hybrid generation,
1909-10.
2nd generation, 1910-11.
3rd generation, 191 1- 12.
* Note. — The white sport was bred from ordinary variegated buff parents and very much in-bred. One pale buff cock, in particular,
appeared several times as father in previous generations, the white hen being his granddaughter on both sides.
this pair in 1909-10, I reared three buff cocks and
three buff hens (see Tables 72 and 73). No
" whites " appeared, which is, of course, what I
expected. The white sport hen died before the next
season, so I was unable to use her again, and was
left with her young ones (three buff cocks and three
buff hens) to carry on the experiment. Some of
them were clear and some variegated.
These three buff cocks and three buff hens I
mated together in 1910-11 and obtained from them
forty-eight buff chicks and eighteen white ones,
proving their hybrid character (see Tables 72 and
74). Nine of the " whites " were reared, six
cocks and three hens, and I kept five buff hens
to breed with the following year. The buff cocks
I did not use for breeding as I had not white
hens enough to spare to test them with to see
if they carried white blood. Also there would
certainly be some dominants in them and I did not
want to increase my breeding operations or to
multiply the buff birds — for which reason I did not
use the buff hybrid cocks of the first generation
again, but used only the white cocks as mates for all
the hens the following year.
The three buff hens of 1909-10 (first hybrid
only buff birds, no white ones appearing in the nests
at all, which looked as though they were dominants,
(see Table 77), the other four hens having
sixteen buff chicks and twenty-seven white ones,
evidently being hybrids, or impure dominants (see
Table 78).
The details of each nest are made out in the
accompanying tables. The eggs were carefully
numbered and the young had numbered rings on
their legs, so that there should be no mistaking the
birds belonging to each pair.
The white chickens are easily distinguished
directly they are hatched, as their skin is a pale
bright pink, quite unlike the ordinary yellow appear-
ance of a common hatching. Very often (but not
always) the hybrid chicks have a pinkish-yellowish
body when first hatched, but this soon turns yellow,
and is never the bright light pink of the white chick.
Also the hybrid chicks are generally (but not always)
very pale in the nest feathers, quite a creamy white,
but becoming brighter yellow later, although many
remain very pale, but not all of them. It was on
account of these two peculiarities of the hybrid birds
that I mated the two buff hens (see Table 79) to
the white cocks, as I suspected that they would have
November, 1913.
KNOWLEDGE.
403
young white ones, which they both did have.
Hen I. (1907-8) I hatched in my own aviary,
and she was almost white in the nest feathers and
always continued very pale, and when mated to a
goldfinch gave me pied mules. Hen II. (1909-10)
had peculiarly pinkish-yellowish chicks, so I
suspected her too of carrying white blood, and in
1910-11 mated her to a first hybrid generation buff
cock, from which mating I got only one pale hen.
The following year (1911-12) I mated both mother
and daughter to a white cock (1910-11, second
generation), and got white chicks from both
of them. The daughter is the hen in Pair IV. in
Table 78.
I have other pale hens (older) related to the white
sport (but not descended from her), as Miss Lee
and I have for many years exchanged birds from our
aviaries. These hens I intend this year to mate
with white cocks, to prove if they are hybrids or not,
as I fancy some of them carry white blood too.
(Miss Lee, I think, must have many birds capable of
producing white chicks — as her birds are mostly very
pale — but she does not I think care to experiment
systematically.)
Table 73.
Results of Mating Buff Cock, 1908-9, to White
Sport Hen, 1908-9.
Unrelated.
Pair.
Buff
Chicks.
White
Chicks.
Remarks.
Original.
4 broods.
2
2
3
2
0
0
0
0
The young ones in
the third nest
died.
9
six sur-
vived.
1st Hybrid Genera-
tion, 1909-10.
Table 74.
Results of Mating 3 Buff Cocks and 3 Buff
Hens, 1909-10.
1st Hybrid Generation from Buff Cock and White Hen
Sport, the Hens being the Sisters of the Cocks.
Pair.
Buff
Chicks.
White
Chicks.
Remarks.
I.
6 broods.
3
3
2
4
3
3
0
1
1
1
1
0
II.
6 broods.
4
4
1
4
3
3
1
0
1
1
1
2
III.
7 broods.
1
3
4
1
2
0
0
0
1
0
3
1
1
2
48
18
2nd Generation from
White Hen, 1910-11.
Table 75.
Results of Mating 3 Buff Hens, 1909-10, of the 1st
Hybrid Generation to 3 White Cocks of the 2nd
Generation, the Hens being the Mothers of the
Cocks.
Pair.
Buff
Chicks.
White
Chicks.
Remarks.
I.
5 broods.
2
1
0
0
2
2
2
3
1
0
II.
5 broods.
1
0
4
0
1
1
4
2
0
3
III.
4 broods.
0
0
2
1
3
1
1
3
14
26
Table 76.
Results of Mating 3 White Cocks and 3 White Hens,
1910-11, 2nd Generation from White Hen.
Pair.
Buff
Chicks.
White
Chicks.
Remarks.
I.
3 broods.
0
0
0
2
4
4
The first hen died
half-way through
the season. All
the birds were
white, as was ex-
pected and hoped
for. It appears
that white colour-
ation is recessive
according to
Mendel's law.
II.
4 broods.
0
0
0
0
0
5
2
0
III.
4 broods.
0
0
0
0
3
2
0
3
0
25
3rd Generation from
White Hen.
404
KNOWLEDGE.
November, 1913.
Table 77.
Results of Mating 2 Buff Hens, 1910-11, and White
Cocks, 1910-11, all Second Generation From
White Hen Sport.
Pair.
Buff
Chicks.
White
Chicks.
Remarks.
I.
4 broods.
3
4
2
3
0
0
0
0
Apparently these
two hens were
dominants, a s
they gave no
white chicks in
any nest.
II.
3 broods.
3
3
4
0
0
0
22
0
3rd Generation,
1911-12.
Table 78.
Results of Mating 4 Buff Hens, 1910-11, and White
Cocks, 1910-11, all Second Generation from White
Hen Sport except the Hen in Pair IV.
Pair.
Buff
Chicks.
White
Chicks.
Remarks.
I.
3 broods.
0
3
2
3
2
2
Apparently these 4
hens were im-
pure dominants,
as they gave
white chicks as
well as buffs.
The hen of the
4th pair was
descended from
the White
Sport Hen on
the father's side
only, though
related on the
mother's.
II.
3 broods.
3
1
1
0
3
1
III.
3 broods.
1
2
1
3
2
2
IV.
3 broods.
0
1
1
4
2
3
16
27
3rd Generation,
1911-12.
Table 79.
Results of Mating 2 Buff Hens (closely related
to the White Sport, one being One Year older
and one being One Year younger, but not directly
descended from her, both having ancestors in
common and both being descended from the Pale
Buff Cock mentioned in the Note (Table 72), to
White Cocks, 1910-11.
Pair.
Buff
Chicks.
White
Chicks.
Remarks.
I.
2 broods.
0
0
1
1
Other nests of the hen
in Pair I came to
nothing. The hen in
Pair II was the
mother by a buff cock
(1st Hybrid Genera-
tion) of the hen in
Pair IV. in Table 78.
II.
3 broods.
3
1
3
2
1
1
7
6
Note. — I mated these two buff hens to white cocks as I knew
they were both related to the White Sport, and I thought, for
several reasons, that they might carry white blood. Evidently,
the white blood must have been in the strain several years before
the White Sport was hatched. No more whites have appeared in
that aviary, but they have not tried for them systematically. I
have other old hens related to the White Sport, which I am mating
this year to White Cocks, to see if perhaps they will prove to be
hybrid from their breeding results.
Table 80.
Results of Mating Jonque Cinnamon Hen and White
Cock.
Unrelated.
Pair.
Description of young birds.
I.
fl jonque green hen.
■] 1 buff green cock.
\ 1 clear buff hen.
No whites
appeared, as
3 broods.
("1 buff green hen.
was expected.
| 2 clear buff cocks.
The buffs are
[l yellow bird (died young).
exceptionally
pale coloured.
J 3 green birds.
(2 yellow birds (died young).
All my birds (and also Miss Lee's) are buff, being
bred from buff cocks and buff hens, except the
progeny from the jonque cinnamon hen (see Table
80) from which bird I have one jonque green hen,
to be mated this year (with the other young of the
cinnamon hen) with a white cock. This cinnamon
I bought, and it is quite unrelated to my other stock.
The clear buff hen in the cinnamon's first nest was
extremely pale (quite white in patches) in its nest
feathers, and has remained extremely pale, as have
also the two young clear buff cocks in her second
nest ; thev are quite as pale as any of my buff
birds bred from clear buff hens and white cocks,
and much paler than many of them. This is re-
markable as the basis of cinnamon colouring is green.
All my white birds have black eyes, not pink as
one might imagine they would have, and they are
very strong and hardy, being bred and reared out of
doors and living in an open out-door aviary all the
year round.
In their case their white plumage does not seem
to make them delicate.
Altogether I think the experiment has been most
successful, as I have established my race of white
canaries breeding true to colour, and apparently the
colours yellow and white obey the Mendelian laws,
producing dominants, impure dominants (or hybrids)
and recessives.
November, 1013.
KNOWLEDGE.
405
From a photograph,* by De la Baume Pluvinel Alcala de Chisverl, Spain, August joth, 1903,
Figure 419. Prominences that can be seen by means of an ordinary telescope only during an eclipse, but which are
shown at all times when a telescope is armed with prisms of wide dispersion.
* Horizontal Refractor and Coelostat. At. 0.153m. ((>"). F. L. 11.880m. (38' llj".) Exp. 2 sees.
From a photograph by G. XV. Ritchey, Mount Wilson Observatory,
February gth, iqto.
Figure 420. Owl Nebula in Ursa Major (N.G.C. 3587)
showing the central star, the bilateral symmetry, and the
concentric appearance that would occasionally be a late
stage in the third body produced by a graze of suns.
Fiom a photograph by G. IV. Ritchey. Mount Wilson Observatory,
July 2nd-4th, 11)10.
Figure 421. The Nebula in Cygnus (N.G.C. 6992), show-
ing details brought out by the camera which are too
faint directly to affect the human eye.
I
406
KNOWLEDGE.
November, 1913.
From spectrograms taken with- a 2-prism Jliut spectroscope by E. 11. Hills, Pulgaon, India, January 22nd iSq-S.
Figure 422. A:,: and B I , spectra showing the flame bands of the reversing layer of the Sun seen during an eclipse.
C, the dark lines of the ordinary spectrum when the Sun shines through glowing metallic vapours.
* At point of second contact. t At point of third contact.
TlTR*
! • . -J '-'-1 .lis 1. „ ■imi.j biiiiO ■ ■_
f ■...*- ' • ' ' ' ' ' '
LyR/6
Castor - F«mr<?rStaf
Fiom spectrograms by William Hu^gins, Tulsc llni.
Figure 423. Spectra of pre-solar stars (compared with the Sun) showing the many dark bands of hydrogen, all of which
become bright bands at a certain stage in the life-history of novae.
STELLAR SPECTROSCOPY FOR BEGINNERS.
By PROFESSOR A. W. BICKERTON, A.R.S.M.
I. INTRODUCTORY HISTORIC SKETCH.
The arming of the telescope with the prism and
photographic plate has produced another bound
forward in astronomical discoveries as great as that
made three hundred years ago, when Galileo armed
the eye with his wonderful optic tube. The tele-
scope extended our knowledge into such abysses of
space that the millions of miles to the distant Sun
became almost too short a unit with which to
measure them. It showed us that the filmy light of
the Galaxy was a seed-bed of millions of suns, as
Democritus so clearly described it two thousand
years before. Some of these suns proved to be so
vast as altogether to dwarf our majestic orb. The
telescope showed us also that the distant inhabitants
of space possess as great a diversity of structure as
immensity of mass.
The cipher messages unfolded by the prism were
to reveal the most unexpected truths : these
rainbow-tinted strips of light we call spectra, told us,
not merely the structure, but also the chemical
composition of the many members of those distant
regions.
The year 1642, when Galileo died, was that
in which Newton was born. Amid his many
wondrous discoveries of appliance and of principle
it had been the especial privilege of Galileo to apply
the telescope to the reaping of a rich and varied
celestial harvest. Newton continued to garner this
wonderful harvest, but he also sowed the seed of
another crop of results scarcely to be begun to be
reaped before two and a half centuries had elapsed.
This fertile experiment of Newton's was to place a
prism of glass in a beam of sunlight that streamed
through a hole in the shutters of a window ; thus he
analysed and decomposed the light into its constitu-
ents. It was a wonderful but crude experiment, for
the lovely strip of light he so produced was what we
call an impure spectrum. Newton never much
improved on his beautiful basic experiment ; it did
not occur to him to use a narrow slit instead of a
round hole, to prevent his colours from overlapping,
and so render his tints pure. It was reserved for
Wollaston and Fraunhofer to do that, and so
discover that the spectrum of the Sun (as Newton
called the coloured strip of light) was broken up by
black bands. Wollaston saw these bands, but
thought too little of them to take much trouble to
perfect his experiments. Not so Fraunhofer : he
carefully plotted them, and named them with the
letters of the alphabet to distinguish them, and so
we still call these revealing ciphers Fraunhofer lines'
By-and-by it was found that the light of burning
metals gave coloured lines instead of a rainbow-
tinted strip, and soon, in the hands of Bunsen and
Kirchhoff, this furnished a means of detecting the
chemical elements : an instrument was constructed
to do this which was called the spectroscope, and
spectrum analysis was born.
Spectrum Analysis.
It had long been known that the colour of these
flames was characteristic of many elements, and
these varied colours were used to give beauty to
fireworks and as aids in chemical analysis. If we
examine a set piece in a pyrotechnic display with a
spectroscope, the instrument spreads each colour out
into a series of separate lines of light. The yellow
in a firework display is caused by sodium, and this
element gives a brilliant yellow band. If an
exceedingly narrow slit be used in a good spectro-
scope, the band separates into two parts, and if the
light be passed through several prisms, the two
constituents may be obtained at quite a distance
from one another. Kirchhoff noticed that the exact
position of these two bright yellow sodium bands
was occupied by two black bands in the spectrum
of sunlight. He afterwards discovered that the
characteristic bright line of other glowing metals
corresponded with other sets of black lines in the
solar spectrum. Further experiments showed that
the bright bands given by a soda flame became
reversed when the electric light was allowed to shine
through it. The continuous spectrum produced
by the electric arc was crossed with black lines
when it shone through the yellow flame. The whole
mystery of the Fraunhofer lines was cleared up, the
sun was a blazing ball of fire shining through an
atmosphere of flaming metals ; hence we had the
basic discovery that in the radiant beams coming
from the Sun we were able to read its composition
and character (see Figure 422). With added refine-
ments, the same method was applied to the suns
that shine at night; the songs of the singing
atoms were read, and told us the story of the
stars. A great principle had been revealed to
man : the same elements that have been used
to build this Earth go to make up the structure
of the heavens. Gradually, as revelation after
revelation has come to us, we realise that " all are
but parts of one stupendous whole," that Nature is a
407
408
KNOWLEDGE.
November, 1913.
complex unity ; and the latest revelation of all that
the stars are telling us in the cipher messages is
that the scheme of creation is a cyclic system
infinite and immortal.
the Physics of the Stars.
The principle of isochromatic reversal was not
merely to tell the chemistry of the heavens, but,
joined to another fact called Doppler's principle, was
to unfold all kinds of physical facts and astronomic
wonders.
doppler's principle.
The express that took me to the British Associa-
tion Meeting at Birmingham passed another express
that had its steam whistle in full blast. As the
train approached the note was ghastly in the high
pitch of its shriek ; suddenly, as the engine passed,
the note dropped enormously, to be followed
instantly by a low-pitched groan. I had often
noticed the pitch of an insect's hum drop as it
passed me, and, standing on a railway bridge, had
heard the note of a steam whistle change as it
passed under the bridge. But the passing of those
two swift expresses gave me an illustration of
Doppler's principle that I have never heard equalled
before.
Each vibration produced by the approaching
whistle was made in a position nearer to us than
the former impulse, so they were closed up and
became shorter ; a shorter wave produces a higher
pitch, and so the whistle shrieked ; when the train
had passed, and was going away, each vibration
originated at a more distant point and the waves
were lengthened, the note consequently dropped,
and the high shriek became a low groan.
The same principle applies to colour: the slow
waves of light are red, the swift ones violet, the
other tints have intermediate velocities. Suns, when
very close to one another, have been pulled by mutual
gravitation, so that they may have speeds of
hundreds of miles a second ; the pitch of the definite
waves produced by each kind of their singing
atoms have the pitch of their definite waves of
light altered, and they become shorter as the
suns approach, and longer as they recede.
Hence a pair of suns that in our most powerful
telescopes appear to be a single point of light may,
under the spectroscope, give us a spectrum in which
a characteristic line of hydrogen may appear double,
and each line be displaced from the normal position.
In such a double star the sun approaching us will
give us lines displaced towards the violet, and the
sun receding a line displaced towards the red end of
the spectrum. Thus the spectroscope reveals the
motion as well as the composition of heavenly bodies.
If the pair of suns graze, a third body is struck off,
like the spark from flint and steel. In the case of
the exploding third star, produced in this way by
grazing suns, the quickly expanding and ensphering
shell of hydrogen that would be produced, as
described in "Knowledge" in September 1911,
would be made up of atoms moving in all directions
away from the nucleus of the exploding sun, and
hence in all directions to our line of sight (see Figure
420). The atoms moving towards us would give lines
displaced towards the violet, and those away from us
towards the red. Intermediate directions would have
resolved velocities that would fill the space between
these. The single line of light that would be pro-
duced were the hydrogen at rest, would broaden
into blaze bands, occasionally showing an opposite
speed on the two edges of each band of thousands
of miles a second. In the special case of Nova
Persei, the displacement in each direction was fully
a thousand miles a second. This is perhaps the
most interesting historic example of the physical
reading of stellar spectroscopy. The details of these
two wonderful principles of reversal of light and
change of speed will be given in detail in the
succeeding articles. Figure 423 shows the dark
bands of hydrogen as seen in ordinary stars.
THE ASTRONOMY OF THE INVISIBLE.
This principle of relative motion of lines reveals
the existence of dead suns by their influence on
luminous stars ; the spectra of some stars are seen
to have their bands moving periodically backwards
and forwards on the spectrum. Such a pair of stars
are one class of what are known as spectroscopic
binaries, so called because it is only in the spectro-
scope that the fact that they are double stars is
revealed. Because in addition, as in the case of
Algol the Demon Star, the dark star sometimes
eclipses the bright one, we are able to deduce their
orbits, and thus weigh and measure these two
properties of the two constituents.
SOLAR ECLIPSES.
When the Moon exactly covers the face of the
Sun, as it did for a second or so last year, if we arm
the telescope with a prism, a series of images of the
circular rim of light is produced. There is a
different ring for each special note of the vibratory
atoms of the various metals. We thus get a most
singular spectrum covered with rings of light,
instead of straight lines; some of the rings overlap
one another and some stand clear. Probably it is
not more than once in a century that the disc of the
Moon and the Sun thus exactly overlap and leave the
reversing layer to be seen all round. There is only
one small spot on all the Earth (and that not
precisely known) where it can be seen. Its duration
is something like a second. Yet the photograph of
this rare and elusive phenomenon was actually taken
last year in Portugal by James H. Worthington. It
will be published in the next number of
" Knowledge." The same principle is used during
ordinary eclipses to photograph the great crimson
hydrogen flames and the metallic outbursts that
spring from the Sun (see Figure 419).
By means of the same method of placing a large
prism in the path of the rays gathered by the
telescope it is possible to so dilute the ordinary
November, 1913.
KNOWLEDGE.
409
white solar light that the monochromatic light of
the hydrogen flame may be seen when there is no
eclipse. By making an extremely long spectrum
the ordinary sunlight is so spread out as to be in-
significant, whilst the red monochromatic light of the
flames retains its intensity, and thus we are enabled
to see these red flames during ordinary sunlight.
THE PHOTOGRAPHIC FILM.
Another principle adds greatly both to the power
of the ordinary telescope and particularly when the
optic tube is armed with a prism. It is the
application of photography to astronomy. One
wonderful effect is obtained by photography ; the
human eye soon tires, whereas the photographic
film will continue to add to its effects for hours or
even days, and thus filmy masses of light that
would for ever have remained undetected imprint
their message on the sensitive plate until, as in the
case of the nebulae of the Pleiades, details of
structure are shown connecting up the whole of
this beautiful cluster of stars, yet with the ordinary
telescope, used by the naked eye, the stars seem to
stand out on an almost absolutely dark background.
An example still more remarkable of the minuteness
of its detail is given in Figure 421. Another
effect of photography is that the film may be
left exposed, or exposed automatically, so as to
record effects when no one is near. Perhaps the
most wonderful of all the applications of photo-
spectroscopy is the work done in Harvard Observa-
tory and its branches, of the wholesale automatic
photography of the spectrograms of large numbers
of stars, taken all at once.
THE IMPORTANCE OF THEORY.
Years ago Newcomb feared that the science of
astronomy would be buried beneath the tremendous
mass of uncorrelated facts that were then accumu-
lated ; yet in spite of this the whole endeavour of
astronomy, until quite recently, has been merely
further accumulations. This state of things is
passing ; endeavours to correlate astronomical
phenomena are being made by able men, both in the
New World and the Old. And although these
endeavours have not hitherto been eminently
successful, nor much accepted save by their respect-
ive propounders, yet the attempts are promising
symptoms of the times. There is a distinct advance
on the part of astronomers in their willingness to
receive the assistance of workers in other branches
of science. Physicists and chemists are allowed to
read papers before astronomical societies. On the
other hand the learned societies representing
experimental science now make room for cosmic
generalisations. At the British Association Meeting
joint conferences of many sections were held.
All this is very hopeful, for nothing causes science
to spring forward by such leaps and bounds as great
generalisations. Although they are thus the mile-
stones in human progress, generalisations have
generally been neglected for something like half a
century. We are not without examples of disastrous
neglect in the present age of science. The broaden-
ing outlook gives us at present a better prospect and
supplies a probability that research will be no
longer mere vicious specialisation, but each expert
will do his work with definite purpose and in
correlation with the sum of knowledge.
Amid all the tremendous rush of present discovery
there is no branch of knowledge that is correlated so
widely in all directions as spectroscopy, and no
scientific worker should be ignorant of its basic
principles.
CORRESPONDENCE.
RAY FLORETS IN THE DISC OF
CHR YSA N THEM UM.
To the Editors of " Knowledge."
Sirs, — I enclose you a photograph of a specimen of the
common Marguerite (see Figure 505, page 431) in which two
strap florets have been produced in the centre of the group
of tubular ones ; the two strap florets were surrounded at
their bases by a small involucre. I have not seen a flower
like this before, and thought the reproduction of the photo-
graph might be of interest to readers of " Knowledge."
Newcastle-on-Tyne. JOHN HUME.
AUSTRALITES.
To the Editors of " Knowledge."
Sirs, — The short account given by Mr. G. W. Tyrrell
(page 308) on the subject of " Australites " (which formed the
subject of a memoir by Mr. E. J. Dunn, of Victoria,
Australia) has interested me very much.
In the year 1909 it fell to my lot to make a journey from
the coast of Vera Cruz up to near Mexico City on horseback,
accompanied by another geologist. The trip took four days,
and we rose close on seven thousand feet.
On the second day out, my companion who had done the
same journey previously, said to me, " To-morrow we shall
pass beds of sand and sheets of basalt, and I want you to
give me your unbiased opinion about the relative geological
positions of the sands and basalt, i.e., whether the sands lie
above the basalts or vice versa."
The third day brought us to the sands, and on seeing a
pure white silvery sand I at once said, " Why, that is not
sand, it is volcanic ash," and you can imagine my astonish-
ment when, on examining the sand with my pocket lens, I
found that a large percentage of the grains consisted of
perfect little bubbles.
No doubt the greater part of the remaining grains would
be " Australites," but this I did not know at the time.
I think that the conditions in Mexico prove conclusively
volcanic origin, for amongst the sand were later on discovered
pieces of fibrous pumice and a large amount of dark green
obsidian.
The obsidian, by the way, gave the source from which the
supply was obtained to make the numerous arrow-heads and
long flat needle-shaped spears frequently picked up in the
coastal regions.
I hope that the above will prove of interest to your
renders
F. W. MOON (A.M.I.C.E., F.G.S.),
Tandjong Poera, Sumatra.
THE STORY OF THE CHIN.
By LOUIS ROBINSON, M.D.
The human lower jawbone differs in a very essential
manner from those found among the rest of the
Primates — and all other vertebrates — in having its
lower anterior border bent downwards and forwards
The elephant (see Figure 431) has a kind of
chin, and among older writers in the pre-evolutionary
days this fact was adduced as showing its superiority
to other quadrupeds. But we now know that the
Figure 424. Atnphitherium oweni
(Stonesfield State).
Figure 425. Dromatherium
(Upper Trias, N. Carolina).
Figure 426. — Arsinotherium
(Eocene).
so as to form a chin. Recent discoveries of the
remains of early men, such as the Heidelberg and
Piltdown jaws, have informed us that this distinctive
shape of the inferior maxilla has increased in a
marked degree since the lower stages of man's
existence (see Figures 500 to 504).
I propose to discuss in the present article some of
the causes which appear
to be responsible for this
curious deviation from
type. That these causes
were evolutionary factors
of considerable potency
becomes fairly evident
when we examine further
into the facts. The general
type of the mandible among
terrestrial vertebrates has been curiously uniform
from the very earliest times, as may be seen in the
illustrations of mesozoic and eocene jaws (see
Figures 424 to 426). It is, we may say, fixed
or stereotyped to a remarkable degree. This makes
the search for evolutionary forces which have so
changed it in our own species all the
interesting.
more
elephant's chin is a mere degenerate remnant of the
long lower jaw of his ancestors, the tetrabelodon (see
Figure 429) and the mastodon (see Figure 430).
In the illustrations to which reference is made the
process of its downward evolution is plainly shown.
Another interesting example is found in the dugong
and its relations (see Figures 482 to 484). Here
a little search into palaeon-
tology shows that this
apparent chin is not, like
the elephant's, a relic of
decayed functions, but that
it has, like that of man,
increased and improved
with the ages. As seen in
the illustrations the du-
gong's collateral ancestor,
the halitherium, and its big extinct relative, known as
Steller's sea-cow (Rhytina gigas), had "chins" also,
but in a less marked form. As a matter of fact the
downward prolongation of the mandible in these
animals is not a chin comparable with our own at
all, but is merely a kind of bony rostrum on which
the dugong and its relations wear their horny false
teeth. This structure, with its curious change of
Figure 427. Pariasaurus. Figure 428. Inostransevia
Figure 429. Tetrabelodon.
There are certain apparent chins found among
other vertebrates, a few typical instances of which,
with their probable evolutionary causes, it may be
interesting to discuss briefly.
Figure 430. Mastodon.
Figure 431. Elephas
primigenius.
angle, is more comparable to the bony support of
the flamingo's bill than to a human chin. A very
curious fact is that we appear to find the nearest
resemblance in the whole animal world, whether
410
411
KNOWLEDGE.
November, 1913.
432. Fossil Lemur. 433. Macaque monkey.
434. Chimpanzee 435. Siamang gibbon,
(young male.)
436. The Naulette jaw
(Spy type.)
437. Akka Pigmy,
from Central Africa.
438. Bushman.
439. Hottentot.
440. Deaf Mute 441. An ordinary
(French). European type.
Figures 432-441 show the progressive stages from the beginning of the Genial Pit
in the Lemur to the fully developed Genial Tubercles in modern civilised man.
442. Hottentot.
443. Hottentot.
444. Bushman.
445. Hottentot.
446. Bushman.
447. Hottentot. 448. Bushman. 449. Andaman Islander 450, Veddah 451. Low type
(Negrito). (Ceylon). (West Africa.)
FIGURES 442-451 show the imperfect development of Genial Tubercle and the persistence
of the " Simian Pit " among certain low races with only imperfect articulate speech.
CASTS OF THE INS1UES OF LOWER JAWS.
November, 1913.
KNOWLEDGE.
412
452. Bushman 453. European Child 454. European Child 455. European Child 456. Ancient Egyptian,
with tubercles. (six years old). (fourteen years old). (sixteen years old).
Figures 452-456 show the development of the tubercles in young Europeans
compared with those well developed in savage and civilised people.
457. Fuegian.
458. Aino.
459. Bushman.
460. Hottentot.
461. Bengali.
462. Tasmanian. 463. Australian. 464. The prehistoric Heidelberg jaw. 465. O'Brien, the Irish giant.
Figures 457-463 afford a study of the remarkable Figures 464-466 show the contrast between the prehistoric
variety of the tubercles in different races.
type and the well-developed mo.lern type.
466. Maori.
467. Japanese. 468. Tartar. 469. Malay.
Figures 467-470 show the general similarity in races that are
somewhat akin in blood and language.
470. Chinese.
CASTS OF THE INSIDES OF LOWER JAWS.
413
KNOWLEDGE.
November, 1913.
471. Wolf.
472. Leopard. 473. Chacina Baboon. 474. Anubis Baboon.
FIGURES 471-474 show the marked contrast on the inner
side of the jaw between the dog-like apes and the Canidae
and Felidae.
475. Lemur.
476. Howler Monkey. 477. Proboscis Monkey. 478. Chimpanzee with
exceptional pit.
Figures 475-478 form an extremely heterogeneous group.
479. The Piltdown jaw.
480. Profile section of the 481. Central African Pigmy.
Heidelberg jaw.
Figures 479-481 show prehistoric jaws compared with a low type
of modern savage.
CASTS OF THE 1NSIDES OF LOWER JAWS.
414
KNOWLEDGE.
November. 1913.
Figure 482. Halitherium.
Figure 483. Steller's Sea Cow.
Figure 484. Dugong.
FIGURE 485. The Jawbone of a Chimpanzee,
showing mots of teeth ami the stout buttressed socket of the canine filling the side
of the "Chin."
Figure 486. The lower Jaw and Tongue of a Macaque,
from a drawing of a dissection by the Author, showing the deep pit for the
origin of the genio-g-fossits muscle.
Figure 487. Human Jawbone with part of the Tongue,
drawing showing the spreading Jasciculi of the genio-gtossits muscle, and their origin from the
upper genial tubercle.
489. Siamang.
Figure 488. Transverse section
through the Tongue,
diagram showing gaiio-glossus muscle penetrating
the intrinsic muscles. After Quain.
491. Chimpanzee. 492. Dog.
493. Man.
494. Pig.
Figures 489 to 494 show the under surface of the tongue and the proportions of the genio-glossus muscle.
November, 1913.
KNOWLEDGE.
415
ancient or modern, to our
own mandible in a group
of some of the earliest
reptiles that have yet
been discovered. In the
Figures 427 and 428 of
those strange thero-
Figure 496.
Diagram of the genio-glossus
pronouncing
muscle
in
sound
the
Oo.'
Figure 497
Figure 495.
Diagram of the genio-glossus
muscle at rest.
morphs, Pariasaurus and
Inostransevia, unearthed
by Professor Amalitzky in
the Permian strata on
the shores of the northern
Dvvina, we see an extra-
ordinary chin which re-
sembles our own in several
striking anatomical particulars.
How such a resemblance comes to
exist I do not even venture to guess ;
but most assuredly Nature's moulding
forces, which so shaped the mandibles
of these ancient reptiles, were totally
different from those cerebral activities
largely responsible for the chin of
civilised man. We say so more con-
fidently because casts of their skull-
cavities show that they had no brains
to speak of, the whole cerebral cham-
ber being of about the same calibre as
the tunnel for the spinal marrow.
When the writer discussed this
subject before the British Association
at Birmingham, and there suggested that the
needs of the mechanism for articulate speech
would probably account for the essential changes
in man's lower jaw, it was pointed out by Professor
Elliot Smith that man's face differs from those
of his nearest congeners in many other particulars
quite as remarkable as these. I hope some
day to show that most of these other changes
have been profoundly influenced, if not actually
caused, by structural necessities demanded by arti-
culate speech. To attempt to do so now would
take me beyond the scope of the present subject,
and I shall therefore confine my attention merely to
the changes that have taken place in the mandible.
In the many endeavours that have been made to
explain the why and wherefore of the chin, the
argument as to its being due to sexual selection
deserves most notice. It has been rightly said that
the chin is essential to the beauty of the human
countenance, and therefore in a choice of mates,
those deficient in this direction would be losers in
life's race. Arguments from aesthetics are very
Diagram of the genio-glossus
muscle in pronouncing the
letter " K."
difficult to handle, because of the extraordinary
differences in the standards of beauty, not only
among different species of the lower animals, but
among different nearly related races of men. Who
can doubt that among the anthropoid apes there is
a type of apish beauty (including the retreating
lower jaw) which satisfies the most critical and
exacting simian taste in choosing a mate ? We need
not do more than allude to the peculiar aesthetic
standards obviously existing a little lower down the
scale among the baboons, drills, and mandrils.
A chin is now unquestionably a sine qua non of
human beauty. But how did it become so ? When
did the simian ideal cease to flutter the hearts of our
primitive ancestors ?
Do we not find that almost all the adorable
features which have this disturbing and fateful
influence nowadays are based upon and are the sign
of some intrinsic quality contributing to racial
efficiency which lies behind mere appearance ? The
lower races are continually, to the great embarrass-
ment of sundry Colonial Governments, desirous of
mating with a superior race differing from them in
physique and in colour. There can be
no question that if the colonists in
such cases were not the superior race
this evidence of the working of sexual
selection would not appear. It would
seem, therefore, that the primitive
man who was manly and, amongst
other manly attributes, had a chin,
scored all along the evolutionary line
in mating contests over the prim-
itive man who was apelike. The
individual or the race which does not
recognise the upward stream of
tendency in such particulars by
instinct alone cannot be found upon
the surface of
this planet.
One argument against
the sufficiency of sexual
selection in producing a
chin, is the well-known
fact that man in the
early stages of his exis-
tence muffled up his
Figure 498.
Diagram of the genio-glossus
muscle in pronouncing the
letter " T."
lower jaw with a beard,
which is, almost with-
out doubt, of purely or-
namental value. Hence
it would seem that the
Figure 499.
Diagram of the genio-glossus
muscle in pronouncing the
sound " Ah."
416
KNOWLEDGE.
November, 1913.
chin per se as a sexual orna-
ment was a failure. Women,
it is true, have not adopted
this form of hirsute decoration ;
but I doubt if this goes far
in helping the aesthetic
argument, since, according to the
ideals generally current, a big
jaw and formidable chin are
nowhere considered an excellent
thing in woman. I think we
shall find that before aesthetics
came greatly into play, more
prosaic evolutionary forces had
already exerted pressure upon
the lower jawbone, and had
begun to mould it into the
general shape in which we find
it now.
A glance at the drawing of
the mandible of a chimpanzee
(see Figure 485) with the roots
of the teeth exposed shows the
real status of the chin in the
anthropoids. It is mainly
formed by two thick bony
buttresses supportingthe sockets
of the lower canine teeth.
This apparently was the real
physical beginning of the bony
chin, or rather was, as it were,
the gross concrete foundation
upon which evolutionary forces
of another kind have based the
modern structure.
It is a most remarkable and
suggestive fact that after man
(or the infra-man) had lost his
huge lower canines, this abun-
dance of bony tissue in the
lower edge of the mandible did
not disappear, but became more
marked as an anatomical feature
(see Figure 487). From analogy
with the elephant, such a
degeneration should have taken
place at once. That this did
not happen is a proof that the
part more than justified its
continued existence by perform-
ing some function of vital
importance to the species.
Sir E. Ray Lankester, in one
of his delightful scientific
causeries, has pointed out that
man's chin consistsof something
more than a bony prominence
on the jaw. There is a distinct
fleshy pad upon its outer
surface, which materially influ-
ences its outline and which
consists of fatty tissue bound
Figure 504. Modern man.
up in little cushion-like com-
partments almost exactly com-
parable to the pads on our
fingers and toes. Although
the aesthetic and sex influences
may be apparent here rather
more than in the bony
mandible itself — for who can
gainsay the charm of a softly
rounded chin ? — the probable
origin of this cushion - like
covering is to be found in the
fact that the protruding chin
needed a pad for exactly the
same reason as do a cricketer's
shins. It was into a world
full of brutal tumult and hard
knocks that the nascent chin
first made its appearance ! In
the prize-ring to-day it is a
well-known fact that a blow
on the chin is the most rapid
way of putting your opponent
hors de combat ; and, more-
over, it has become apparent
that the nearer the exponent
of " the noble art " is in
structure to a chimpanzee or
gorilla the better chance will
he have of wearing the glorious
" Champion Belt of all the
World." If we look at the
bony structure of the chin in
some of the prehistoric jaws, we
find it of astonishing strength,
being stout and buttressed as
if to stand terrific violence.
This is remarkably shown in
Emil Selenka's admirable
monograph on primitive jaws,
published by Kreidel, of Wies-
baden, in 1903. From the
above facts it seems reasonable
to infer that man acquired such
advantages as a chin can give
at his peril ; and here, again,
it is suggested that some
evolutionary need, of excep-
tional potency, moulded man's
jawbone into its modern shape.
It is when we turn a human
mandible round and look at it
from the inside, and observe
the surface beneath the central
incisor teeth, that we begin to
get hints as to the actual func-
tions of the chin and the causes
which have led to our deviation
from ancestral type. About
half-way between the rim of
the central tooth-sockets
and the lower edge there
November, 1913.
KNOWLEDGE.
417
are to be found in practically all European and in
most other jawbones two bony prominences known
as the genial tubercles (see Figure 441). Below
them are two somewhat similar prominences,
generally much smaller (which often appear as
faint convergent ridges), which are also known to
anatomists as genial tubercles; but these, I think,
we need not consider of any importance in the
present argument. They are to be found, not only
in the lowest savages and in prehistoric men, but also
in a large number of the apes and other vertebrates ;
indeed, I have detected apparent traces of them
in those strange Permian reptiles of incalculable
antiquity to which allusion was made above. They
are the points of attachment for a little muscle
which appears to be equally developed in man and
in many of the lower creatures. It is known as
the genio-hyoideus, and has no connection with the
tongue.
A close examination of the larger bony prominences,
or the genial tubercles proper, reveals some very
interesting and remarkable facts, especially when we
employ comparative methods. To these are attached
the tendon of the fanlike genio-glossus muscle
which spreads out beneath the whole lower surface
of the central region of the tongue, and penetrates
through the intrinsic muscles almost to the upper
surface (see Figures 487 and 488). Now if we
examine any of the current books on anatomy, little
or no suggestion is found that the functions of the
genio-glossus muscle have to do with articulate
speech. Let us leave the mandible for a while and
confine our attention to the structure and functions
of this muscle, and I think it will soon become
evident that it has more to do with the oral (as dis-
tinct from the laryngeal) machinery of articulate
speech than any other structure.
In the diagrams (see Figures 489 to 494), which
show the under surface of the tongue of man and
other creatures more or less related to him, it is
seen how remarkably this muscle has become
developed since we became human. The functions
accorded to it in our standard works of anatomy
would apply to the needs of the dog and the pig
equally to those of man ; yet we see that in these
animals it is a mere feeble slip of flesh which can
exercise but little influence.
I have dissected it in a good many apes, among
which animals it evidently had somewhat important
duties quite apart from vocal production ; in fact, I
doubt whether in any other creature except in man
we should find the tongue interfering in any way
whatever in the sounds which issue from the larynx.
The muscle is not only much smaller in apes than in
man, but it is much more homogeneous and compact
(see Figure 486) ; while, so far as I have been able
to observe, the method of innervation shows an even
greater difference than is seen in the structure of the
muscle itself. To put the matter very briefly, in
man the genio-glossus has become a series of a large
number of independent muscular strips which are, to
all intents and purposes, separate muscles, each with
its little fibre of the hypoglossal nerve entering it
in such a way as not to hamper its free movement,
while in the apes it is apparently a single muscle, or
a closely united group, acting en bloc.
It must be remembered that the adoption of an
exceedingly important new method of expression
and communication such as human articulate
speech would require widespread and most elaborate
changes in the structures which it brought into play.
It is not possible on the present occasion to go into
the marvellously intricate cerebral, nervous, and
muscular machinery, with its innumerable bonds of
coordination required for ordinary speech ; but a
little search into the matter will show anyone that
we are here in contact with one of the most incre-
dible marvels in Nature. Most wonderful of all, the
whole mechanism is, from an evolutionary standpoint,
quite new — a product of merely the later fragment
of a brief geological period !
When we consider the number of movements,
following one another in continually varying order,
required for articulate speech, it is obvious that only
machinery which is able to act with every
mechanical advantage and with a minimum of
friction, can accomplish such a task with precision.
Public speakers frequently talk at the rate of one
hundred and fifty words a minute, while it seems
possible to articulate quite clearly and correctly
when speaking at the rate of one hundred and eighty
words a minute. If we analyse the action of the
tongue when speaking at the rate of one hundred
and fifty words a minute, we find that there must be
at least five hundred different movements or adjust-
ments. This gives eight or nine in every second !
Such movements, it must be remembered, do not
follow one another regularly in mechanical rotation
like the piston-beats of a multiple-cylindered engine,
but are continually varying their order. What
wonder is it that coordination sometimes breaks
down, with the result of a stutter or a stammer ?
Now a brief examination of the intrinsic muscles
of the tongue, i.e., those that begin and end in the
tongue itself like the distal muscles of an elephant's
trunk, will show how totally inadequate these would
be to produce any such result ; but immediately one
takes careful note of the mode of action of the genio-
glossus muscle the solution of the tongue's incredible
agility becomes possible.
It is seen in the accompanying diagrams (see
Figures 495 to 499) that the several bundles, or
fasciculi, of the muscle are able to act more or
less at right angles to the main plane of the tongue
without anything to hamper them. For each flash-
like movement of the tongue away from the palate
all that is demanded is an instantaneous shortening
of one or other of these independent strips. For
instance, in pronouncing the letter T we place the
tip of the tongue against the palate close to the
upper incisor teeth (see Figure 498), and then
snatch it away with great rapidity. The placing
it there is probably the work of the intrinsic muscle
called the superior longitudinal lingual, but the
418
KNOWLEDGE.
November, 1913.
more critical action of withdrawing it at the proper
moment is due to the front fibres of the genio-glossus,
which become taut and braced for instantaneous
action as soon as the tongue-tip is pressed against
the palate.
In Figure 497 it is seen that in the hard G or K
exactly the same thing takes place with the central
fasciculi of the muscle. A like action comes in with
sounds involving L, N, R, D, J, Q ; while in S, X,
and all other consonants where the nice adjustment
of the distance of the tongue from the palate is a
matter of moment the genio-glossus muscle is
capable — and appears to be the only structure
capable — of exercising a quick and exact control.
The same applies to the vowels, as is well shown
in the accompanying diagrams after Von Meyer's
drawings. Von Meyer, however, has not shown
the genio-glossus muscle in action as it is shown
here, and indeed, strangely enough, does not give
it a word of mention as a factor in articulate speech.
It is worth while to take note of the fact that
practically all the speech-movements of the tongue
take place in the neighbourhood of its central line,
and that the sides play a very subordinate part.
Hence the other extrinsic muscles, such as the hyo-
glossus and stylo-glossus can have little or no part
in articulation (see Figure 488).
Now let us return to our inferior maxilla and
examine the attachments and relations of the genio-
glossus. It is obvious that for quick, precise move-
ments, such as those demanded by articulate speech,
it must be unhampered and have plenty of room to
act. An examination of the arrangements for the
play of the muscle in different animals is exceedingly
instructive. In the dog, and indeed the majority of
the mammalia, the tongue lies flat upon the lower
jawbone leaving practically no room for any muscular
machinery. If, however, a photograph of a plaster
cast of the inner surface of the wolf's jaw (see
Figure 471) is compared with that of the baboon (see
Figures 473 and 474), which outwardly resembles it,
a remarkable difference of shape is evident.
In all the monkeys — and even lower down the
scale among the lemurs — we find that Nature has
made provision for working room for the
genio-glossus muscle by excavating a kind of
pit on the inner surface of the mandible beneath
the tongue. This pit has been noticed by
various comparative anatomists, but I had never
seen any explanation of the reason why it exists, nor
was I aware of its function, until a series of dissec-
tions of monkeys' jaws showed in every case the tiny
tendon of the genio-glossus coming from the lower
surface of the deepest part of the pit (see Figures
433 and 486). The more doglike the jaw is, as in the
baboons — the more, in fact, it corresponds in general
outline with the prevalent type of the mandible
among lower vertebrates- — the deeper is this pit.
As soon, however, as the mandible begins in some
degree to resemble our own, as in some chimpanzees
and gibbons, and the whole lower surface becomes
tilted forwards, the pit seems to be no longer needed,
and becomes shallower. One may as well remark in
passing that it is of course obvious that originally
the genio-glossus muscle had nothing whatever to do
with articulate speech. The need it met in the
economy of lemurs and apes was probably that of
giving increased mobility to the tongue for sorting
food already in the mouth. This is plainly seen
when we give a monkey a nut and see him crack it
and turn it about with his tongue, selecting the
kernel and rejecting every fragment of shell. This
ability common among all the Primates to sort food
with the tongue, and with its aid to eschew unac-
ceptable morsels, is strikingly absent in the case of
most animals. Anyone can assure himself of
this on seeing a dog try to get rid of some small
unpalatable object. Animals such as cattle, and
especially camels and giraffes, which are liable to get
dangerous thorns into their mouths, depend upon a
most elaborate arrangement of the long papillae
lining their cheeks, so that by a simple backward
and forward movement of the tongue such things
are at length extruded.
There seems little doubt but that it is this sorting
machinery of the tongue in the lower Primates which
has been seized upon and greatly elaborated for the
new and wondrous mechanism of articulate speech.
Before going further it may be as well to clear up
another point which seems to have puzzled some of
my audience when I was lecturing at Birmingham.
The question was asked me, " How is a parrot able to
talk if he has no chin ? " An equally pertinent
question would be, " How is a phonograph able to
talk when it possesses no chin ? " A parrot has
deep down behind its breastbone a marvellously
elaborate and versatile sound-producing apparatus,
almost as different from any possessed by ourselves
as is the mechanism of a phonograph. When man
began to speak, he had to make use of raw material,
which was there already, to build up his talking
machinery. That the parrot and the phonograph
can speak, merely proves that there are other ways of
doing it ; but the only question which we here have
to discuss is how man did it himself with such
means as were at his disposal.
When we come to examine the difference between
prehistoric man and modern savages we find the
same order of structural change in the mandible still
going on, tending to the greater efficiency of the
genio-glossus muscle for speaking purposes. When
this fanlike group of muscular fibres came out of a
deep pit, such as is seen in the illustration of the
jaws of the lower monkeys, the fibres were obviously
hampered by being bunched and huddled together
(see Figure 486). As the jaw became tilted
forward, giving more engine room beneath the
tongue, the need for the pit became less, and it
becomes shallower and shallower until we find it a
mere depression, as in the Siamang gibbon (see
Figure 435). These changes are plainly shown
in the series of plaster casts of which photo-
graphs are reproduced in Figures 432 to 441. First
of all is a fossil lemur, in which the jaw still retains
November, 1913.
KNOWLEDGE.
419
its generalised character, but is beginning to show
depressions as the genial pit makes its appearance ;
then one has apes like the baboons, macaques, or
colobus monkeys with an exceedingly deep pit or
depression. Next come anthropoids, in which the
lower edge of the jaw is already being dropped into
something resembling a chin, and the depression at
once becomes less apparent. Next are some
jawbones of prehistoric man, namely, the Heidelberg
and the Naulette jaws, in which the depression is
still plainly seen and is scarcely less marked than in
the gibbon.
It will be seen that the Heidelberg jaw shows on
its surface a tubercle ; indeed, I understand that one
of the descriptions of it published soon after it was
found stated that it did not differ from modern jaws
in this respect (see Figure 464). A brief comparison
with the other casts, however, will make it plain
that the tubercle here seen is too low down to be
that for the genio-glossus, and is plainly the one for
the genio-hyoid muscle mentioned in the earlier part
of this article, which has nothing whatever to do
with the tongue. This tubercle is quite common
among the apes.
When we come to the Pygmies and Bushmen we
find in the majority of jaws the remains of this pit
or a mere flat surface ; but in some African dwarf
races, and among the Hottentots, Veddahs, and
Andamanese, two little prominences are seen
beginning to grow at the lower edge of the pit (see
Figures 442 to 452). These tubercles, as we pass to
higher and more civilised races, become more and
more prominent, until we get the European type
familiar to all students of anatomy.
Now the bearing of these changes on the
functions of the genio-glossus muscle is fairly
evident. First of all, it needed a deep pit in the
lower apes to get room to work at all. Then the
depth of the pit became unnecessary through the
tilting of the lower surface of the mandible ; and by
means of this change the muscle was obviously given
greater freedom for action. Then we get a nearly
flat surface ; and finally a prominence appears,
enabling the separate fasciculi of the muscle to
spread from the very point of origin and so act
independently without hampering their neighbours
(see Figures 441, 455, 461, and 465).
We are thus able to follow the whole course of
the history of the genio-glossus muscle from fossil
lemurs to modern men, and a very remarkable
history it is, difficult, I believe, to parallel in any
other structure of the body which we may pick out
for the purpose. We found it in the lower apes, in
which it first appears as an important factor in
tongue movements, coming out of a hole in the
lower jaw, and we take leave of it mounted upon a
pinnacle quite as high as the pit was deep (see
Figures 486 and 487). This is as if an organism
commenced its career in the uttermost depths of the
sea, and attained its full development at the top of
Mount Everest ! The muscle might stand above all
things else in our bodies as a symbol and sign of our
upward progress. For I think it cannot be denied
that its development marched pari passu with the
development of intellectual capacities and the
increasing need of a means of clear expression.
When speech began, as distinct from mere animal
stereotyped cries and other noises, it is, of course,
impossible to say. For the speech of certain low
savages, consisting of grunts, guttural sounds, and
clicks, it is fairly obvious that few tongue move-
ments are necessary ; but wherever languages have
become more elaborate — and many of them in
different parts of the world appear to have had an
independent origin from more brute-like utterances
— we find that the genio-glossus muscle comes more
and more into play, as is evidenced by its tubercles
of attachment and by the forward tilt of the chin to
give elbow room among all the higher races.
The speech of monkeys is, of course, a myth, and
most of our anthropoid friends are curiously silent
beings. The two exceptions appear to be the chim-
panzee, which is described by travellers as shouting
and calling in varied tones in the forest, and certain
gibbons, which appear to come nearer to us in the
variety of articulate utterances than any other of
the Primates. From the series of plaster casts
shown in the plates, and in many others that are in
my possession, it seems to become evident that,
speaking generally, the genial tubercles may be taken
as some index of social and intellectual development.
They are not, of course, strictly necessary for speech,
but it is clear, both from anatomical and general
reasons, that they greatly facilitate speech.
It is interesting to watch their development in the
normal human subject (see Figures 453 to 455), and
I have several casts which illustrate this fairly
clearly. In all young children they are absent, and
up to the age of fourteen years they make but a
small show ; in fact, the jaw of a child of fourteen
years almost exactly resembles in this respect that of
a Bushman or Pygmy ; between fourteen and seven-
teen, however, they appear to obtain their full
development. How far that development is
dependent upon the use of the muscle it is difficult
to say ; my own belief is that, like many of the
roughnesses and ridges upon our bones, they are
very largely the product of vigorous muscular
action, i.e., Nature has met the obvious need of the
muscle by altering the bone in a certain specific
direction.
For many years I have been endeavouring to get
evidence as to the presence or absence of the
tubercles in deaf mutes. Such as I have, so far as it
goes, seems to show that in adults who have never
acquired articulate speech they are quite absent
(see Figure 440). In the one specimen I have
from a deaf mute, the bone almost exactly resembles
that of a Bushman, or a child of fourteen.
A glance over the peculiarities of the tubercles in
the accompanying plates shows how extraordinarily
variable they are in different individuals and in
different races (see Figures 457 and 458), but before
any safe generalised conclusions are drawn
420
KNOWLEDGE.
November, 1913.
from these diversities one ought to have many
thousands before one for comparison. It seems to
me quite probable that this would prove a fruitful
line of research for anyone with leisure and
opportunity to follow up ; for, when we consider
the distinct anatomical problems involved in the
pronouncing of different languages it seems not im-
probable that definite structural peculiarities might
become apparent in accordance with the " tongue "
spoken. We know that it is practically impossible
for Europeans to acquire the elaborate tongue and
throat movements of not a few barbarous languages,
and it would be extraordinary indeed if this wide
diversity in muscular function did not leave some
trace which the methods of the anatomist might
reveal.
In Figure 465 is reproduced a photograph of
a cast from part of the jawbone of O'Brien, the
Irish giant, the capture of whose body gave
John Hunter so much trouble. I placed it
there, because it shows the typical arrange-
ment of the genial tubercles in a very marked
manner. It also tells us something else, which
I think is not a little instructive. There can
be no question that the Irish speak our
language with much greater correctness and pre-
cision than the average Anglo-Saxon, and further
investigations seemed to show that in Irish jaws
there was a fuller development of the genial
tubercles than in those found in English museums.
On following the same line of research a little
further it became apparent that a greater symmetry
and uniformity of the development of the genial
tubercles was to be found in French and Italian
jaws than in English. This seems to be a matter
well worth following up.
A few other suggestive points come out from a
further examination of the plaster casts, reproduced
in the plates, which have no very direct bearing
upon our present enquiry. One, for instance, is the
obvious kinship between certain American monkeys
and the lemurs, as evidenced by the duplicated pit
(see Figures 475 and 476). In nearly all the Old
World apes of which I have specimens, the two
cavities appear in close proximity or merged into
one, but in the American monkeys and the
Madagascar lemurs they are generally separated
by a marked interval. The lower jaw in certain
highly specialised apes, such as the howler and
proboscis monkeys, appears very difficult to inter-
pret. Here again a more extended collection, giving
opportunities for exact comparative methods, would
be certain to throw a good deal of light on what
is at present a subject which seems to have been
very little studied.
Apart from these by-products of the enquiry I
think it will be acknowledged that many of the
facts put forward in this article go far in justifying
my suggestion that the chin, which is so marked a
characteristic of the modern human mandible, may
be considered part of the necessary mechanism of
articulate speech.
Note : The illustrations in the above article are by Menie Gowland.
REPORTS.
THE YORKSHIRE NATURALISTS' UNION.— By the
unanimous vote of the council of the Yorkshire Naturalists'
Union the President for the next year will be Mr. T.
Sheppard, F.G.S.,of Hull. The Yorkshire Naturalists' Union
is one of the most successful associations of its kind in Great
Britain, and has published many important monographs on
the flora and fauna of the county, and also issues The
Naturalist, which is one of the oldest scientific monthly
magazines in the country. The Union has a membership of
nearly four thousand, and about forty important natural
history societies are affiliated with it. Until recently Mr.
Sheppard was the Honorary Secretary, and took a leading
part in the editing and publishing of its important monographs,
and there is no doubt that it is largely due to his efforts that
the Union owes its present influential position. Mr. Sheppard
is well known from the excellent work he has done in connection
with the three municipal museums at Hull. He is the author
of numerous books and monographs, as well as of the remark-
able series of Hull Museum Publications, close upon a hundred
of which have been published during the past fourteen years.
He has already filled the presidential chairs of the Yorkshire
Numismatic Society, the Hull Geological Society, the Hull
Literary Club, the Hull Scientific Club, and the Hull
Shakespeare and Playgoers' Society.
CAN LEAD BE TURNED INTO GOLD ? — At a
meeting of the Alchemical Society on Friday night, October
10th, Professor John Ferguson, M.A., LL.D., and so on (of
Glasgow University), delivered an interesting address on
English Alchemical Literature, in the course of which he
said the English literature on the subject was not very bulky
although it might be precious. Other chemical and technical
processes had very extensive literature in which the various
discoveries were traced. So far as he knew there was no gold
made by alchemists in existence at the present time. When
they saw a gold medal they knew it was gold, but there was no
proof that gold was ever made from mercury, lead, or any
other metal. Even if a piece of gold was produced which was
alleged to have been made by an alchemist, they had no
knowledge at present as to how it was done. He had never
come across an old book or manuscript on alchemy which
ever explained the method by which base metals could be
transmuted into gold. There were many manuscripts extant
at the British Museum and the Oxford Library bearing on the
subject, and in them one could find enough material to occupy
his whole attention for many years.
He did not propose to deal with the manuscripts because of
their great abundance and also because of their inaccessi-
bility, but would confine his remarks to books printed in the
English language on the subject. There were many books in
Latin whose authors are Englishmen, but he had not time to
deal with them. The earliest printed book on alchemy was
published somewhere about the year 1474 or 1480. Probably
it had been taken from a manuscript, and so far as he knew it
was the only book on the subject printed in the fifteenth
century. A number of books were printed in the sixteenth
century, and still more in the seventeenth century, but after
that the number declined, and during the eighteenth century
and nineteenth century most of the books dealing with the
subject were reprints. The lecturer then dealt in great detail
with the various authors, most of whom claimed to have
discovered the secret powder for transmuting base metals
into gold. There was a wide field for research work among
the manuscripts at the British Museum and the Oxford
Library. Whether any of those manuscripts contained the
precious secret he did not know, but he hoped that now he
had called attention to the literature on that subject it would
lead others to investigate the matter, which was a very
interesting one.
THE NOMENCLATURE OF VARIABLE STARS.
By F. A BELLAMY, M.A., F.R.A.S.
The present state of chaos in the nomenclature used
for variable stars — and it is daily increasing — calls for
careful consideration by astronomers to remove some
of the present anomalies, and, in view of the immense
increase in the number of known variable stars —
which will be still further increased by photographic
means — to establish some definite, convenient,
intelligible, and permanent notation.
The beginning of astronomical observations of the
variability in the light of stars may be placed in the
year 1572 with the discovery of the star which is
usually known as Tycho Brahe's Nova in the constel-
lation of Cassiopeia, or sometimes as B Cassiopeiae.
In the next hundred years three more such stars
(Novae) were discovered in 1600, 1604, and 1670,
and are known as P Cygni, a star in Serpentis, and
11 Vulpeculae. Until about one hundred years ago
not many observations of the variability in the light
of stars, or of Novae, are recorded. Systematic and
careful estimations of the magnitudes of certain
stars were made about seventy-five years ago, chiefly
by Schmidt (of Athens), Argelander (of Bonn), Heis,
and, later, by Hind, Pogson and J. Baxendell in
this country : their observations soon proved the
degree of variation of light in a number of stars they
had kept under frequent observation ; and, incident-
ally, these observers — to be more precise Argelander
and Pogson — laid the basis of the scale for accurate
stellar magnitudes, and afforded us both the means
of determining relative magnitudes and of carrying
on a magnitude scale with a definite light-ratio.
One may say quite fairly that for the last seventy
years all visual estimations of stellar magnitudes have
been made on this basis (Argelander and Pogson)
without change, and Pogson's value of the light-
ratio, or difference in the star's light from one
magnitude to the next, of 2 • 5 12, or logarithm 0 ■ 400,
has since been universally adopted, though Professor
E. C. Pickering's latest photometric work indicates
a slightly different value ; also he proves that
Argelander's magnitudes of the fainter stars observed,
8-0 to 9-5 magnitude, require diminishing by some
tenths of a magnitude : this is probably due to the
small size of Argelander's telescope, which is still
in situ at Bonn as when last used by Argelander
and Schonfeld. This by way of a parenthesis to
indicate the origin of accurate stellar magnitudes ;
for, without a uniform basis, the observations upon
variable stars for the determination of their periods
would be useless.
Returning to the definite subject of this note, the
first catalogue of variable stars appears to have been
that formed and published by Argelander in 1844,
and was published in Schumacher's " Jahrbuch," on
page 214. This catalogue contained eighteen stars
only, and all were well situated for observation in
what is now the German Empire : it may be of
interest to give them.
First Catalogue of Variable Stars.
o Ceti, |8 Persei, x Cygni, R Hydrae, R Leonis, v Aquilae,
(3 Lyrae, * Cephei, a Herculis, R Coronae Borealis, R Scuti,
R Virginis, R Aquarii, R Serpentis, S Serpentis, a Cassiopeiae,
a Ononis, a Hydrae.
The capital letters have been added to some of
these stars. The stars, when read horizontally,
are in the order of discovery; Novae were omitted
by Argelander ; they are mostly bright stars, and
ten of these have the old Greek notation, which
remains in variable star nomenclature as for all
other astronomical purposes. Of the other eight,
seven have the prefix R, and one the letter S. As
some of the capital letters beginning at A had
already been used by Bayer, about two hundred
years earlier, Argelander formed the scheme of
applying the letters of the alphabet, beginning at
R, to the stars shown to be variable, other than
those already designated with Greek or other letters.
So soon as enough variable stars had been discovered
to require the letter Z, the sequence was to be con-
tinued with the duplication or combination of letters ;
thus after Z the next in the series would be R R to
R Z, S S to S Z, and so on to Z Z. The necessary
complement of these prefixes was the name of the
constellation ; so the full designation for a variable
star might be R Andromedae, R R Aquarii, or Z Z
Cygni. This form of nomenclature was sufficient
for forty-five variable stars in each constellation.
Until a few years ago the discovery of new variable
stars depended upon visual work, and this nomen-
clature sufficed for all needs. With the greater
application, or rather a closer examination, of the
many thousands of photographs that have been
taken at Harvard College and other observatories
(mainly at Harvard), the number of new variable
stars is being increased by hundreds a year; the
result is that the method of Argelander has broken
down — at least for certain constellations.
In 1909 the number of variable stars was more
than forty-five (= Z Z) for the constellation of
Cygnus. Recourse was then had to the dual use
of the letters beginning with A A — single letters
could not be used, for, as I have pointed out, many
single capital letters were already in use for non-
variable stars. The continuance of this notation,
421
422
KNOWLEDGE.
November, 1913.
it is intended, shall run on after Z Z, with the letters
A A, A B, AC, and so on, prefixed to the name
of the constellation. If this part of the dual
notation be not continued beyond A Q, B Q, and so on,
there will be provision for one hundred and thirty-six
additional variable stars in each constellation. If
it be continued, as is being done in Hartwig's
Ast. Gesell. annual catalogues, from A A to A Z, as
far as Q Q to Q Z (always omitting J), then there will
be provision for two hundred and eighty stars, besides
the fifty-four from R to Z Z for each constellation.
In 1909 there were eighty-six constellations in
which one or more variable stars had been dis-
covered. The state of this lettered nomenclature
in 1909 was that in the constellation of Scutum
there were nine lettered variable stars and thirty-one
waiting for letters, in Sagittarius twenty-seven
lettered stars and seventy-four waiting, in Scorpio
twenty-five lettered stars and eighty-four waiting,
and in Orion there were nine lettered stars and one
hundred and twenty - five waiting for letters of
identification. In 1912 the constellations of
Cygnus, Scorpio, Sagittarius, Centaurus, Carina,
Aquarius, Aquila, Hercules, Andromeda, and Draco
had almost exhausted the R to Z Z section of the
alphabet ; in fact, A K was reached for Scorpio, AO
for Sagittarius, while for Cygnus the alphabet with
dual notation had been passed through once, and
A Z reached. For Scorpio there were thirty-nine
more lettered variable stars than in 1909, and yet
there were forty-five more already discovered and
waiting for letters. At the rate at which variable
stars are being photographically discovered it will
require but two or three years, perhaps, for the
whole alphabet to be used up in the dual form. To
continue to ring the changes with triples would be
cumbersome. The single or double letter form with
the figure 3 as an index might be convenient, both
for manuscript use and print, as R8, S8Z, or A3Q ;
but any extension of the scheme by mere variation
of printers' type — as has been suggested — would be
extremely inconvenient, and a source of many errors.
We shall now return to the historical side of the
subject and resume the thread of Argelander's
Catalogue of 18 variable stars published in 1844.
Though the lettered nomenclature had been in
use for some years, Argelander had given no very
definite account of the scheme until that which
appeared in the Astronomische Nachrichten, No. 959,
1855, May 3rd ; this explanation may be given best
in his own words : —
" Mit R bezeichne ich den Stern in der Jungfrau, dessen
periodische Veranderlichkeit Harding im Tahre 1809 entdeckt
hat, und dessen Position fur 1855 ist: 12s 31m 9s + 7° 47'- 3.
Dass ich einen nicht bei Bayer vorkommenden Stern mit
einem Buchstaben bezeichne, wird mir hoffentlich nicht
verdacht werden. Die veranderlichen Stern haben bei ihrer
Merkwiirdigkeit wohl ein Anrecht auf eine solche Auszeich-
nung, die zur Bequemlichkeit der Nachweisung bei so oft
erwahnten Sternen fast unentbehrlich ist. Um aber eine
Verwechselung mit den Ba^er'schen Buchstaben moglichst
zu vermeiden, habe ich die letzten des Alphabets gewahlt, und
sie dem grossen Alphabete entnommen. Nur im Hercules
gehen die lateinischen Buchstaben bei Bayer bis z, im Stier
bis t, in der Jungfrau bis q, im Lowen, Orion und Schwan
bis p ; im letztern Sternbilde ist dies ein grosser Buchstabe.
Bayer kennt sonst fur seine Bezeichnungen in den Stern-
bildern von den grossen Buchstaben nur das A ; die andern
grossen Buchstaben, die auf seinen Charten vorkommen,
weisen entweder auf hellere Sterne benachbarter Sternbilder
hin oder auf ausgezeichnete Puncte der Himmelskugel. Nur
bei dem bekannten neuen Sterne vom Jahre 1600 macht er
eine Ausnahme, indem er ihn mit P bezeichnet ; er sagt : ' P
tertii fulgensstella, anno MDC primum conspecta et observata,
omnium ferme tacito consensu pro novo phaenomene recepta,
eundem adhuc hodie retinet situm e.q.s.' Ich kbnnte somit
Bayer als meiner Vorganger bei dieser Auszeichnung der
veranderlichen Sterne citiren ; indess glaube ich, dass dieser
Astronom daran nicht gedacht hat, sondern den Stern in seiner
vor 1600 schon fertigen Charte, vielleicht erst auf der
Kupferplatte, nachgetragen, und desshalb die Ordnung nicht
unterbrechen wollte ; er hatte ihn sonst nach seiner Methode
mit 7, 7 mit S bezeichnen miissen, u-s-w, also waren alle
folgenden Sterne geandert worden."
The nomenclature proposed and used by Argelander
was generally adopted. Here is an example by
Dr. R. Luther (Bilk) in Ast. Nach. No. 996 (1855,
November 29th) : " welcher nach dem Argeland'-
schen Vorschlage (in No. 959 der Ast. Nach.)
T Piscium bezeichnet werden moge."
Argelander's Catalogue was followed by Norman
Pogson's pioneer work at the Radcliffe Observatory,
and he published a catalogue of 53 stars in 1854,
using Argelander's notation ; G. F. Chambers,
who is still living, published a list of 123 variable
stars in the Astronomical Register, II, 194, in 1864,
August ; this was reprinted in the Astronomische
Nachrichten in Band LXIII, page 117; a revised
form also appeared in the Monthly Notices of the
Royal Astronomical Society vol. XXV, page 208
(1865, May), and in later years catalogues of 235
variable stars, 126 probably variable, and 500 red or
orange stars in his Handbook of Astronomy. In these
catalogues he was helped by J. Baxendell, G. Knott,
F. Brodie, and J. E. Gore. In 1865 and 1875
Schonfeld published catalogues. The number then
given was 143 stars: to this number 48 variable and
77 suspected variable stars were added at Harvard
Observatory in 1883, and further lists were
published from Harvard in the Proceedings of the
American Academy of Sciences, vols. XIX-XXII.
In 1888 an Index to observations of variable star
(published) observations was given in the Annals of
the Astronomical Observatory of Harvard College,
vol. XVIII, No. VIII: in this 225 stars are given
and the records of 125,720 observations made from
1838-1888 are indicated.
Chandler published in The Astronomical Journal,
vol. VIII, 81 (1888), a catalogue of 225 variable stars,
with their elements, and a great deal of other
information ; a second edition, containing 260 stars,
was published in The Astronomical Journal, vol. XIII,
page 89 (1893) ; and a third and last edition, record-
ing 393 stars, was published in The Astronomical
Journal, vol. XVI, page 145 (1896). Soon after
this Roberts published a catalogue of 94 stars south
of —23° Dec, a portion of the sky previously much
neglected.
November, 1913.
KNOWLEDGE.
423
Chandler adopted an entirely new notation in his
three catalogues ; we give the reasons for the method
in his own words : —
" The number of a star, upon a system of ordinal notation
designed to remedy the inconveniences attending the usual
current numbers . . . . if the numbers of any one list
are retained, the interpolated stars require a suffix letter,
resulting in a hybrid notation which is exceedingly objection-
able, and which sooner or later has to be reformed ; when the
whole process of degeneration, with its awkwardness and con-
fusion, begins anew. It seems certainly better to adopt a
system which attaches a permanent numeral to each star, and
which permits interpolation to a practically unlimited extent.
I would accordingly suggest that the numbers for variable
star catalogues be one tenth of the right ascension,
expressed in seconds of time, for the equinox 7900-0."
This method limits us to 8640 variable stars in the
whole sky unless we adopt the " hybrid notation "
disparagingly referred to in the above quotation.
The publication known as the Vierteljahrschrift
der Astronomischen Gesellschaft has contained, since
1870, a list of variable stars with ephemerides. The
work was edited or compiled formerly by Winnecke,
Schonfeld, and at present by Hartwig. Up to 1889
it contained stars to 2° south of the equator ; from
1889-1895 stars as far south as — 30° Dec. were
included; from 1895-1902 the catalogues were
extended to — 35° Dec, and after that variable stars
in the whole sky were included ; the catalogue of
1906 contained information for 709 stars similar to
that in Chandler's catalogues. The number in the
catalogue for 1913 is 962 stars north of — 23° Dec.
and 417 stars south of that. During the year 1912
148 new variable stars were discovered, 109 from
photographs and 39 visually; since 1900 about
80 per centum were found by ladies, chiefly from
Harvard and Arequipa photographs. The non-
continuance of the preparation for further editions of
Chandler's catalogue resulted in more attention
being given to variable star work at the Harvard
Observatory. For some years Professor W. M.
Reed had been forming a bibliography of variable
stars, on cards, giving the details for separate
stars, and in 1897 this extensive record had needed
15,000 cards ; then it was continued upon similar
lines by Miss Cannon, who added 20,000 cards ; and
the results of Professor Reed and Miss Cannon's
work formed volume XLVIII, No. Ill (published in
1903), and was called the Provisional Catalogue of
1,227 stars, and is usually considered to be the hrst
catalogue of variable stars independently formed at
the Harvard Observatory. A supplement was
published in The Harvard Circular, No. 77, and a
further supplement is in Harvard Annals, volume
LIII, No. VII. The continuation of this work at
Harvard with still greater vigour, aided by an
exhaustive and comparative examination of portions
of the Harvard extensive series of photographs,
revealed a large number of new variable stars, and a
new catalogue was required. The volume LV,
under the joint editors, Miss A. J. Cannon and
Professor E. C. Pickering, was published in 1907 to
1909 to replace the former first and provisional cata-
logue, and it extends to 291 pages, entirely devoted
to variable star work. This second catalogue con-
tains 1,957 stars, with a supplementary list in Table
IX (page 272). On page 103 of volume LV begins
a list of 167 observers and observatories which have
contributed the observations included.
The variable stars discovered in the globular
clusters are included in this number 1,957, but not
those 1,791 variable stars already discovered in the
Magellanic clouds. To December, 1906 only, there
were 3,748 variable stars to be dealt with : of
these, 2,909 have been discovered at the Harvard
Observatory, mainly from photographs taken there
and at Arequipa; 514 of these 2,909 stars were
found by S. I. Bailey in southern globular clusters,
221 more were detected by Mrs. Fleming from an
examination of third-type spectra (photographs taken
for the Henry Draper Memorial), and Miss H. S.
Leavitt has discovered 2,110 of the total 2,909 stars ;
they were mainly in the Magellanic clouds.
The Harvard Observatory publications and work
upon variable stars really mark the introduction of
an entirely new system, and this brings us to the
third form of nomenclature. The great accession
to the number of variable stars in recent years,
largely owing to the extensive use to which the
photographic gelatine plate has been put, caused
Professor E. C. Pickering to form some easy,
permanent, and inexhaustible method of nomen-
clature for variable stars, and one that would at the
same time afford some other information than a
mere name.
The scheme which he first adopted in the Harvard
Provisional Catalogue was numerical in form, yet
not a mere number, but figures which also give the
position of the star in the sky with sufficient
accuracy to enable an observer to remember or
ascertain from an abbreviated or compact list —
without the necessity of consulting a large catalogue
— whether the star is suitably situated for observa-
tion. The form of designation which was adopted
for the Harvard Provisional Catalogue is retained
in the second catalogue of variable stars in Vol. LV.
The method has been found of great convenience in
actual practice. It is in constant and daily use at
that observatory, and the six figures, to be read
as three pairs, are quite readily retained in the
mind for all stars frequently observed, and the
accuracy indicated by the figures is sufficient to
enable the observer to set the 6-in. telescope and
identify the variable star field readily.
The plan is to give the hours and minutes of the
star's R.A. for 1900, omitting all seconds (not the
nearest minute) and the degrees of declination,
omitting all minutes ; when there are several
variable stars with the same hours and minutes and
the same degree, as sometimes occurs in clusters,
then a small letter is added beginning with a, b, c,
and so on ; in no case yet, we think, has more than
a single letter been required. Though the method
is really independent of the constellations it is better
424
KNOWLEDGE.
November, 1913.
to give them ; the designation almost always indicates
the constellation. The most unsatisfactory point in
the scheme appears to be the dual character for the
northern and southern stars ; if the constellation be
given as well as the number all would be clear for
stars in those constellations beyond fifteen degrees
from the equator. But for those, as Cetus, Orion,
Aquila, and so on, which embrace stars on both sides
of the equator some additional and distinctive
notation must be introduced, and Professor
Pickering continues his custom — as in all his
photometric and other work— of designating all
negative quantities in print in italic type. In a bad
light, or when using a catalogue quickly, one is apt
to overlook the italic type, this is the chief objection
to the method ; but the introduction of a minus sign
would give emphasis to the star being in the
southern hemisphere.
Had north polar distance (N.P.D.) been adopted
instead of declination this difficulty would have been
overcome ; but N.P.D. is very seldom used in
practice, and not many instruments are so graduated.
Let us see how the second Harvard Catalogue
looks. This is a portion of one page : —
Designa-
tion.
Name.
D.M.
R.A. 1900.
Dec. 1900.
h. m.
.
181912
— Scuti
5045
18 19-9
-12 45
182109
— Scuti
4376
18 21-1
- 9 15
182158
RZ Draconis...
...
18 21-8
+ 58 50
182513
X Scuti
5014
18 25-7
-13 11
183149
S V Draconis...
R
18 31-2
+49 18
183146
— Lyrae
...
18 31-6
+46 3
183107
— Scuti
4633
18 31-7
- 7 41
183208
Y Scuti
4663
18 32-6
- 8 27
183342
— Cor. Aust.
13498
18 33-6
-42 20
183647
— Telescopii
12488
18 36-5
-47 21
183604
— Scuti
4553
18 36-7
- 4 13
183606
— Ophiuchi...
18 36-8
+ 6 20
Two-thirds of these had no letters in 1907.
It will be appropriate to make a quotation here
from The Annals of the Harvard Observatory,
vol. LV :—
" The number of variable stars has now become
so large that it is necessary to have some convenient
means of referring to them and of locating them.
The numbers given by the editor of the Astro-
nomische Nachrichten, while very useful for certain
purposes, are not convenient as permanent reference
numbers for the stars. In reading an article which
merely gives, for instance, 21, 1909 Andromedae, one
is at a loss to recall just where the object is, or
whether it is suitably placed for observation. For
this purpose a list must be consulted to find the
position of the object. On the other hand the
designations used here serve to locate the star.
They give the hour and minute of right ascension
and the degree of declination. This is often all that
is needed. An observer can at once make up his
mind whether the object can be observed at present
or at a later time. The objection has been raised
that six figures cannot readily be remembered. On
the contrary, it is found here that they cling to the
memory with remarkable tenacity if constantly
used in connection with each variable. An observer
here,* by whom these [numerical] designations are
used daily, recently made a test. He wrote down
the names of 367 variable stars. For 260 of these
stars he supplied from memory the designations
correct in all six figures."
This quotation introduces the fourth form of
nomenclature now current. It is convenient as a
temporary expedient, but we think it should be
abandoned as being cumbersome and overlapping.
The Astronomische Nachrichten notes the discovery
of variable stars, and each year the series begins
with No. 1 (with the constellation added) ; so,
unless one is careful to add the year, confusion will
soon arise. From this temporary method of
nomenclature the star is advanced to the lettered
form, but that may not be until some years have
elapsed and the star has been proved to be variable.
The application of letters to the variable stars is
years in arrear ; the general result is that we have
four forms of nomenclature for variable stars in
current use.
There is yet a fifth method. Each year, as
already mentioned, there is a catalogue of variable
stars edited by Hartwig, and published in the
Vierteljahrschrift der Ast. Gesell. ; the stars (in the
list for 1913) are numbered from No. 1 to 962 in
order of R.A. for epoch 1855-0, and include only
the stars to — 23° declination ; those south of— 23°
begin at No. 1001 to 1417, but in order of R.A. for
1875-0! At the end of these annual catalogues
there is an alphabetical arrangement of the constella-
tions with the appropriated letters, to which is added
the number in the catalogue. So, as new stars are
added each year, the catalogue number for, say,
R Aurigae will differ almost every year. As only
about 1,400 variable stars are given in Hartwig's
catalogue for 1913, and 3,748 are given in the
Harvard Second Catalogue to the end of 1906, it is
presumed that when the number 999 is reached the
next thousand will have to be skipped and continue
the northern list at 2,000 : this is encouraging
confusion. The epoch for the Harvard Catalogue
is the same convenient date as for the International
Astrographic Survey, 1900 ; and it would save much
time and be of the greatest advantage to practical
astronomy in all its branches, if all positions of stars,
whether approximate or accurate, were always given
for this epoch (1900-0) for the next thirty or forty
years, when 1950-0 might be adopted until the year
2000.
Those interested in variable star work have there-
fore at least five forms of nomenclature and three
different epochs to amuse themselves with, besides
variations for north and south stars. In view
of the fact that continued rapid accessions of new
The Observatory of Harvard College,
November, 1913.
KNOWLEDGE.
425
variable stars are being made to the total,
now well over 4,000, and that only 1,400 of these
have lettered names, it would greatly benefit
astronomy and be to the credit of astronomers if some
international consensus of opinion were obtained, and
a definite and, as far as possible, a permanent scheme
were evolved from the present confusion.
In Chambers's "Handbook of Astronomy," Vol.
Ill, page 271, we read: " Argelander's very crude
and unsatisfactory nomenclature (Astr. Nachr., XL,
959, 1855, May 3) has been followed, but at no
very distant period it will have to give place to
something more artistic." And he wrote as long ago
as in 1865 : " The time seems arriving when it will
be imperatively necessary to adopt a new nomen-
clature for variable stars. The present system,
besides being inartistic, is gradually, and not very
slowly either, drawing to a natural termination."
This period has undoubtedly arrived, and, whether
or not Professor E. C. Pickering's scheme is more
artistic, it is certainly very convenient, of great
utility, capable of indefinite expansion, and with
some modifications, might very well hold the field.
To show how compact and convenient Professor
Pickering's method is we shall conclude this article
by giving a sample of the form in which Professor
Pickering has arranged a table for all the variable
stars with letters (to 1907). The whole catalogue of
lettered stars can be given on four or five pages.
Here is a sample (see Table 81).
The first star R Andromedae has R.A. 0h 18m and
Dec. + 38°; RT Andromedae has a note ; SR, TR,
TS are not used, only letters in direct sequence;
thus, for Cygnus, there are no stars for XR to XW,
YR to YZ, or ZR to ZY. All the stars under
Antlia have south declinations, also most of those
under Aquarius. There seems no valid reason why
letters and Professor Pickering's notation should not
be applied immediately a discovery — with sufficient
verification — in the star's light is announced; we
should get rid of the second, fourth, and fifth
variations in nomenclature and two different epochs.
Even if the star should eventually prove to be non-
variable no harm would be done; in 1920, 1930,
1940, or even every five years from 1915, the
catalogues could be swept clean of those spurious
variable stars and the letters appropriated for others.
The order of the letters is no longer coincident
with the order of discovery, and no chronological
significance would be disturbed.
Table 81.
Index to Designations of Variable Stars.
Constellation.
R.
S.
T.
U.
V.
W.
X.
Y.
Z.
Andromedae
001838
003740
001726
010940
004435
021143a
001046
013338
232848
H
R
004533
235048
r
013238
020448
004132
005840
231539
230552
II
S
T
...
230752
233335
230845
235943
002725
235939
225342
001828
012746
000843
225442
Antliae...
...
100531
092728
092936
103039
...
...
• ••
Aquarii
233815
225120
204405
215717
204102
204104
221321
203905
234716
V
R
210903
210504
221722
231917
210000
211800
...
...
Cygni
...
193449
200357
204334
201647
203847
213244
203935
204834
195849
11
R
204244
200938
' 194048
213753
213937
202539
200747
200635
204846
II
S
...
213843
202954
194029
200647
200346
201130
194232
202946
)»
T
...
193732
194348
203046
210129
205642
192928
191350
»i
U
...
...
213542
192843
201942
205030a
205230
215543
»»
V
210245
201134
205339
210039
214742
J»
w
...
...
...
200041
2014376
214443
204938
»i
X
...
...
...
...
...
200158
194541
193056
H
Y
...
...
...
...
...
...
211841
205840
11
z
...
...
...
...
...
202046
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
YERKES PARALLAX D ETERM I NATIONS.— The
Astrophysical Journal for July contains a further series of
parallax determinations by Messrs. Slocum and Mitchell.
Only four stars on the present list have parallaxes notably
exceeding their probable errors, and three of these are faint.
/uOrionis has a parallax of -"036; Groningen VII, number 20
(RA 16h 21m, N. 48°-6), whose magnitude is only 10-7, has a
P.M. of l"-22 and parallax -"125 ; an anonymous star, RA
17" 33m, N. 18°-6, magnitude 9-1, has parallax -"108, PM
T"36. Curiously enough, there are two other ninth-magnitude
stars close to it which also have large, though not identical,
P.M.'s, but their parallaxes are insensible. The remaining
parallax is an 11-3 magnitude star near 17 Lyrae, whose P.M.
is 1 • "75, parallax -"124 ; its intrinsic lustre must be extremely
small ; if its surface were of the same brightness as our Sun's
its size would be comparable with Jupiter's.
WESTPHAL'S COMET.— This comet, which appeared in
1852, has now been detected on its return by M. Delavan at
the La Plata Observatory, Argentine Republic, of which
Professor Hussey is Director. It was seen at Greenwich on
September 30th, when it was of eighth magnitude and about 3'
in diameter, with distinct central condensation. On November
1st its place will be roughly R.A. 20h 38ra, N. 24° 50';
November 11th R.A. 20h 33m, N. 31° 7'. The following are the
elements: Perihelion Passage, 1913, November 26-1, Omega
57i°, Node 346$°, Inclination 40° 57', Perihelion Distance
1-25, Period 61 • 12 years. The perihelion passage is about a
426
KNOWLEDGE.
November, 1913.
month later than the time that would give the best display. In
1852 it was on October 12th, or a fortnight before the time of
best display. It is fortunate that the conditions should be
good at two consecutive returns. There is little doubt that
the comet will be faintly visible to the naked eye at the time
of perihelion ; it will doubtless be visible in a binocular
throughout November.
This is the fourth member of the Neptune comet family to
be observed at a second return. The others were Halley,
Olbers, Pons- Brooks. There are two others, seen in 1846 and
1847, whose returns are expected about 1921 and 1927.
Westphal's has much the shortest period of the family. Its
aphelion distance is thirty, exactly Neptune's distance, but
there is not a close approach to Neptune's orbit, owing to the
large inclination. The time of perihelion is five months
earlier than that predicted as the most probable by Hnatek
and Viljev. This illustrates the difficulty of accurate predic-
tion in a period of this length.
THE PLANETARY DISTANCES.— I lately received from
Professor Lowell an interesting essay on the planetary
distances and their bearing on the question of the manner
of development of the system. He points out how often the
periods of two adjacent planets approximate closely to some
simple ratio. Thus : —
Mercury to Venus \
Jupiter to Saturn /
Venus to Earth
Earth to Mars
Saturn to Uranus ..
Uranus to Neptune
= i
= I
(A closer)
(A closer)
He suggests that there is not only a coincidence but a law
here, and that " each planet has formed the next in order at
exactly one of these commensurable points, at the same time
displacing it slightly Sunward."
He points out that the action of an outer planet on an inner
practically diminishes the Sun's mass and increases the period,
while the action of an inner one on an outer increases the
Sun's mass and diminishes the period, the second case being
the more effective. Thus a planet once formed tends to draw
neighbouring particles to itself by bringing their periods into
conformity with its own.
He then proceeds to consider the effect of commensurability
of motion, showing that there is a tendency for particles to
swing about the commensurate position ; he suggests that in
time this leads to the building-up of a planet at this position.
The planets would thus have been formed from the inside
outwards, " each acting as a sort of elder sister in bringing up
the next." Jupiter is supposed to have been formed ante-
cedently to the commencement of this action, and Saturn,
Uranus, and Neptune to have been formed outside in
succession, each being drawn slightly Sunward from the point
of exact commensurability. Thus is explained the youthful
appearance and small density of Uranus and Neptune. Had
they started at the same time as Jupiter, their small size
would lead us to expect further development and greater
density. Saturn, on this view, is the youngest planet as
regards stage of development reached, which accords well
with the very small density and the presence of the ring.
The four inner planets are supposed to have been formed
in a similar manner. The present condition of Mars is quite
consistent with an origin later than that of the Earth ; for in
spite of its small size it has evidently not yet reached its
" dead " stage. Professor Lowell points out that though
there are gaps in the minor planets at the distances cor-
responding with periods one-half, two-fifths, and one-third of
Jupiter's, yet the great bulk of them is concentrated near
these points. He suggests that we see here the same con-
gestion of matter as caused planetary aggregation elsewhere,
but in this case it proved abortive.
The paper is an interesting attempt to give a physical
explanation of the existing planetary distances. He ventures
to predict the distance 47-5 (period 328 years) for the planet
outside Neptune. From the analogy of the satellite system he
thinks it likely that it would have a large eccentricity and
inclination. This would make its discovery more difficult,
as a much wider zone would have to be swept.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S
RECENT RESEARCH ON EMBRYOLOGY OF
ANGIOSPERMS.— {Continued from page 384).
Schoute's work on the exact relationship of plerome and
periblem at the growing- point to the central cylinder and
cortex as differentiated in the older regions of the same axis,
whether stem or root, is very important. He accepts Van
Tieghem's definition of the stele as the solid cylinder of root
or stem enclosed within the endodermis. The endodermis
itself is considered as belonging to the cortex because in the
root its cells are opposite the radial files of the inner cortex,
and indeed form the inmost rank of these files ; this is assumed
to indicate a common origin by repeated tangential division.
The cells of the pericycle, the outermost layer of the stele,
alternate with those of the endodermis. As a rule there is no
corresponding radial arrangement in the cortical tissue of the
stem, but where such exists (as in the stem of Hippuris) the
endodermis is again included in it and terminates it. Schoute
in 1903 got precise results in species of Hyacinthus,
Helianthus, and Linum, in the roots of which the periblem
passed into the cortex, its inner layer becoming the
endodermis, and the plerome gave rise to the stele only ; but
owing to difficulties arising chiefly from the insertion of
leaves close up to the stem apex and displacements in the
original stem structure owing to this habit, Schoute found
definite results only in Hippuris, where the plerome gave rise
not only to the stele but also to the endodermis and to the
two or three inner layers of cortex immediately beyond it.
If Schoute's results are well founded the limit between
plerome and periblem does not correspond with that between
stele and cortex in the stem of Hippuris, and doubt is also
thrown on the assumption made by all previous observers that
rows of cortical cells arranged in radial files must be of
common origin.
The stelar hypothesis is essentially an assertion of the real
homology between the vascular systems of stem and root
throughout all vascular plants. No difficulty arises so long as
we are dealing with roots only, or with the stems of those
vascular Cryptogams in which the vascular system is a closed
cylinder without gaps at the insertion of the leaf-traces : in
such plants the vascular cylinder is as well defined as in all
roots and can be described in the same terms. But the case is
quite different in the stems of Phanerogams, where apparently
the primary vascular cylinder is a system built up of leaf-traces
embedded in a parenchymatous matrix. The early anatomists
were faced at once by this problem in its crudest form, for they
began with the primary structure of the dicotyledonous stem,
and that of the root was not clearly understood until many
years later ; since they attempted to interpret it by reference to
the skeleton of the stem and in the same terms ; though there
is nothing in the anatomy of the root to correspond with the
leaf-trace, and the leaf-trace is the vascular unit of stem
structure in all Phanerogams. Even when the facts of root
structure were accurately known, the conception of the leaf-
trace bundle as the structural unit continued to be a stumbling-
block. Modern anatomy dates from 1871, when Van Tieghem
published the first of his series of memoirs in which the axial
core of the root was treated as equivalent to the whole system
of leaf-traces in the stem ; a conception which gained ground
from the first, and was popularised by the happy choice of
the term " stele " in 1886. From that time the stelar hypo-
thesis has replaced all other schemes of vascular anatomy ;
the advance then made on all previous generalisations has
been shown by the new impulse given to research and the
comparative simplicity introduced into text-book anatomy,
though equal simplicity cannot be claimed for the technical
November, 1913.
KNOWLEDGE.
427
language of research in this subject. It is generally accepted
that the central cylinder of the root in Phanerogams is far
more closely comparable to the leaf-trace cylinder of the stem
than to any one of the traces within it, yet when the com-
parison becomes detailed difficulties arise. For instance,
where there is a pith in the root it certainly forms part of the
stele, which is a solid cylinder sharply defined by the specialised
endodermis around it ; but the leaf-traces in the young stem
surround a massive cylinder of parenchyma exactly resembling
the parenchyma of the cortex with which it is in apparent
connection through the gaps between the leaf-traces. Even
the secondary formations in the stem do not completely
divide one system from the other ; when a specialised
endodermis is present it is not so clearly defined as in the
root ; in many cases it is not present, and in a few instances
there is an endodermis around each leaf-trace. However, the
stele in the stem of Phanerogams is not necessarily a morpho-
logical fiction, because in many stems its precise limits cannot
be determined, for morphology is not merely descriptive. If
we suppose that the stem stele in remote ancestors of the
Phanerogams was as well defined as that of the root, and
clearly comparable to it, we may attach a real morphological
meaning to the term when applied to modern Phanerogams,
provided we can show cause to believe that what we call the
stele in their stems represents the ancestral stele. Its tissues
will then have a history distinct from those of the cortex,
though not clearly separated from them. The burden of
proof, however, lies with those who assert that an apparently
continuous and uniform tissue can be separated into two
parts of distinct origin.
The evidence advanced is of two kinds — one founded on the
comparative anatomy of stems and the other on the history
of the tissues of the individual plant. Schoute has collected
evidence to show that in the stems of Angiosperms a
specialised layer is commonly distinguished from adjacent
tissues either by the peculiar thickening characteristic of the
endodermis in the root, or by the presence of starch
in its cells. He shows that such a sheath surrounds
the vascular cylinder in a very large proportion of
Dicotyledons and in a majority of the Monocotyledons,
while among Gymnosperms it occurs but rarely ; and since
the Angiosperms in which this bundle-sheath is obscure or
wanting are commonly closely related to species in which it'
is perfectly well-defined he concludes that its absence in such
cases must be attributed to reduction. Allowing that such a
layer is as general among Angiosperms as Schoute believes,
doubt may still exist as to its homology with the endodermis
of the root, which is defined, not only by its thickened walls,
but also by the fact that the cells form the inmost rank of the
series of radial files distinguishing the inner cortex, while in
the stem the inner cortex cells are very rarely arranged radially.
As regards the second class of evidence, that drawn from
the history of the tissues in the individual plant, we have
already seen that the differentiation of plerome from periblem
is far less definite at the growing- point of the stem than at the
root apex, and doubts have even been thrown on the identity
of plerome and periblem with stele and cortex respectively.
But we must now follow the development of the tissues of the
embryo into those of the seedling. The normal seedling
of all Phanerogams consists at first of cotyledons, hypocotyl,
and root, the plumular bud being still rudimentary. The
primary root lies usually in a straight line with the primary
stem or hypocotyl. The hypocotyl is commonly the first part
of the embryo to lengthen, and then its xylem is lignified a
little earlier than that of the root or even of the cotyledon ;
but when, as in many Monocotyledons, the base of the coty-
ledon lengthens first, lignification begins in that region and
advances through the hypocotyl to the primary root. The
investigation of the anatomy of the seedling at this epoch
becomes extremely important when the vascular system of the
root is compared with that of the stem, for in the seedling
we have a' complete and simple vascular skeleton which at one
end belongs to the primary root of the plant and at the other
to its primary stem ; hence there must be an intermediate
region in which stem structure passes into root structure, and
the method of transition should at least suggest, if it does not
precisely determine, the relation in which they stand to one
another. For this reason great value has been attached by
anatomists to the transitional region of the main axis. Van
Tieghem showed that there are several types of transition
between root and stem, in all of which the xylem and phloem
bundles of the root are continued into the cotyledons or
plumule ; on their way through the hypocotyl they may divide
or be displaced, and the xylem bundles " rotate " (that is, they
turn on their axes until the protoxylem is internal), but all the
elements present in the root are continued upwards in regular
succession and are simply re-arranged in the upper part of the
seedling. Hence Van Tieghem considered that the steles
of root and stem are completely homologous. Gravis and
others, however, consider that there is no morphological
continuity in the hypocotyl between the vascular systems of
root, stem, and leaf : their traces are merely in contact
sufficiently intimate for physiological purposes, but there
is no true homology between the central cylinder of the
stem and that of the root. The third view is that of
Chaveaud, who agrees with Gravis that the presence of
external xylem is the rule in the hypocotyl and in the base
of the cotyledon, but considers that this external xylem
belongs to the primitive structure of hypocotyl and cotyledon
as well as to that of the root.
As already stated, the vascular system of seedlings is first
differentiated in the hypocotyl, base of cotyledon, and base of
primary root. According to Chaveaud, in all these regions
the primitive stele is root-like, the xylem alternating with the
phloem and its development being centripetal ; but this
primitive formation is permanent only in the root and
commonly in the lower part of the hypocotyl also — in the
upper part of the hypocotyl and in the base of the cotyle-
dons the first xylem elements are fugitive and disappear
so early that as a rule they are missed completely by the
anatomist, who is apt to prefer well-differentiated material and
therefore to choose seedlings which are past their first youth.
Chaveaud therefore considers that there is an early phase in
the development of the seedling in which the stele of the
hypocotyl — at that time the only representative of the stem —
is developing on exactly the same lines as the stele of the
primary root, and is, in fact, continuous with it. At that epoch
each cotyledonary trace is also developing on the same plan :
it belongs to the same phase of evolution. In many
Dicotyledons the insertion of the cotyledons is the simplest
imaginable — the original stele of the hypocotyl divides below
the cotyledonary node and one half goes to each cotyledon.
Where this formation is clearly developed there cannot be
said to be any transition between stem and root structure,
since stem stele and root stele are continuous and their
steles are developing in the same way, while even the
leaf-traces of the first two leaves are on similar lines,
and their insertion therefore does not modify the structure
of the stele. The structure we associate with the stem
of Phanerogams appears as follows. In the transitional
region of the hypocotyl the first xylem elements — perhaps
only two or three at each pole — alternate with the phloem
groups. The elements next differentiated lie within them, for
development is still centripetal, but in two diverging groups.
The xylem ray is then shaped like an inverted V. Each arm
of the V approaches the adjacent phloem group as it travels
inwards, until the last-formed elements lie on the same radius
as the centre of the phloem group, but well within it. The
next elements are differentiated on that radius, but are
directed towards the phloem — development has become
centrifugal. These successive xylem formations are termed
by Chaveaud the alternate, the intermediate, and the super-
posed. The alternate elements are fugitive in this transitional
region : they commonly disappear as the superposed elements
become conspicuous. The intermediate xylem persists ; but
higher up in the hypocotyl the intermediate elements also
disappear as the seedling becomes older. Hence in seedlings
of a certain age we have endarch bundles at the top of the
hypocotyl, forming a stele of the stem type, and an exarch
stele lower down, which passes unchanged into the root, the
connection between the two being maintained by the inter-
mediate xylem of the transitional region.
428
KNOWLEDGE.
November, 1913.
Chaveaud believes the stem cylinder in the upper hypocotyl
of a fairly old seedling to be a true stele, but one belonging to
a later phase of evolution than that of the root, and not
strictly homologous with it in the sense in which the earliest
vascular formations in cotyledon and hypocotyl respectively
were homologous with each other. He considers that
the successive vascular formations — marked by the
appearance of alternate, intermediate, and superposed xylem
in turn — represent three successive phases of stelar
development : the root stele corresponds with the first
of these phases only. This implies the hypothesis that at
some past period a group of plants in the direct line of descent
of Angiosperms possessed a stele resembling that which is now
a mere stage in the life of the individual ; thus the alternate
formation found throughout the very young seedling implies
an ancestral group with an exarch stele in stem as well as
root, and a leaf-trace of corresponding structure. If this view
be adopted, the seedling must, during the period when it
consists only of cotyledons, hypocotyl, and primary root, with
the plumule present as a mere bud, represent a past period in
race history when its ancestors possessed an exarch stele in
both stem and root, when the stem stele belonged to the stem
only and the insertion of leaf-traces hardly modified its
structure, and when it entered the root without change, and
therefore no transitional region occupied and puzzled the
anatomist of the period ! This early stage in the development
of the seedling is succeeded by that in which the epicotyl
(plumule axis) begins to grow, and as a rule the epicotyl is
undoubtedly modern : its vascular skeleton is built up of leaf-
traces which are endarch from the first, at the cotyledonary
node they are inserted on the vascular cylinder of the
hypocotyl which has become endarch at the top. This
transition has been effected lower down in the hypocotyl, as
described already, by the formation first of intermediate and
then of superposed xylem together with the gradual disappear-
ance of the original alternate xylem. Hence the cotyledonary
node may be considered to mark the interval between two
acts in the drama of evolution — an interval the length of which
cannot yet be estimated, but is clearly to be reckoned in
geological epochs. The race history of the phanerogamic
stem-cylinder is at present unknown ; possibly the develop-
ment of the hypocotyl may give a clue as suggested by
Chaveaud, or Jeffrey may be right in deriving the leaf-traces
from a simple tubular stele (siphonostele) which has become
more and more broken up by the appearance of foliar gaps.
Until this point is cleared up the exact relationship of the
vascular cylinder of the stem to that of the root will remain
obscure ; as a matter of convenience the stem cylinder will no
doubt be called a stele, even should anatomists acknowledge
that it cannot be considered as strictly homologous with the
stele of the root, but much confusion of thought would be
avoided if the two structures were not treated as strictly
comparable.
Apart from the foregoing consideration of modern
embryology in relation to a single problem of internal
anatomy, namely, the comparison of the vascular system of
the stem to that of the root, the evidence of embryology is
of great weight in questions of internal morphology and
phylogeny. Hanstein's account of the Monocotyledon
embyro suggests two distinct problems : (1) whether a
terminal member can be considered as a leaf, (2) whether
Dicotyledons are derived from a monocotyledonous ancestor,
or Monocotyledons from a dicotyledonous form. The most
obvious interpretation of Hanstein's observations is that
the single cotyledon of Monocotyledons is equivalent to the
pair found in Dicotyledons : this would imply that Dicotyle-
dons were derived from an ancestor with one cotyledon,
apparently terminal, which gave rise to the existing pair by a
process of splitting ; but other interpretations are possible, and
the terminal hypotheses received a shock when Solms-Laubach
discovered that in certain Monocotyledons the single cotyledon
is lateral from the first. The comparative antiquity of Mono-
cotyledons and Dicotyledons has been one of the first
questions raised by the study of seedling anatomy, and it is
remarkable that both the hypotheses founded on work of this
kind assert the greater antiquity of the dicotyledonous form ;
but if the cotyledonary member of Monocotyledons is derived
from one or both cotyledons of an ancestral pair, it cannot
be considered as terminal. Thus the evidence of seedling
anatomy bids fair to settle both these problems, and probably
others of the same kind.
Though the progress of botanical embryology has been
here treated from the morphological side only, it is clear that
every department of botany must deal with the immature
plants as well as with the adult form. For instance, the
struggle for existence between two species in any particular
locality must be profoundly affected by the characters of their
seedlings. If one species should gain a decided advantage
over the other early in life, the vanquished species may never
live to set seed, and may thus disappear from the neighbour-
hood in the first generation. This is an extreme case to show
the importance of considering seedling structure in problems
of ecology and distribution. The internal structure of seed-
lings is certainly a department of vegetable anatomy, just as
their adaptation to the conditions of life is a department of
vegetable physiology. That the connection between embryo-
logy and systematic botany must be equally close seems
at first sight to be beyond dispute, but the exact nature
of that connection is as yet undetermined. Certain features
of the embryo are included among the characters used
by systematists, but on the whole, the latter have dealt
exclusively with the adult plant, the embryo itself having been
treated rather as a portion of the seed than as an individual.
We need not be surprised if conclusions drawn from the new
embryology — that is, the embryology which includes internal
characters as well as external — sometimes appear to conflict
with the results of systematic botany, and it does not
necessarily follow that embryological evidence is of no
systematic value. The fault may lie with the embryologists
who, being human, do occasionally misinterpret their facts, or
possibly the natural system may need some modification in
the light of new knowledge. When both explanations have
failed to account for the discrepancy in a number of cases, we
may be forced to give up looking for phylogenetic results from
embryology.
A summary of various papers read at the Birmingham
meeting will be given in these columns next month.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon), F.I.C.
PATHOGENIC ORGANISMS IN RIVER WATER.—
Mr. A. C. Houston deals, in the Ninth Research Report,
Metropolitan Water Board, with the question of the typhoid
bacillus and its distribution. In a former Report, an outline
of which was given in these columns, it was shown that under
the ordinary conditions of storage and filtration the sewage
micro-organisms in a polluted river water are so diluted that
a very large volume of the water must be examined in order to
detect a single typhoid bacillus. " Where then," as Mr.
Houston asks, " is the typhoid bacillus ? " and he supplies the
answer in the following words : " The home of the typhoid
bacillus is not so much in impure waters, or even in the
crude sewage from a large community, as in the ' factories '
of disease, as exemplified by the ' carrier ' case."
In other words, there may be much less danger in the
contamination of water by the sewage of a whole community
than in traces of contamination from a single individual who
happens to be what is known as a " typhoid carrier." In the
case of the ordinary sewage contamination produced by a
large town the effect of these unknown typhoid " carriers " is
reduced by dilution, so that the water will probably contain
only the normal quantity of typhoid bacilli. Incidentally it is
pointed out that there is but little risk of typhoid infection
from breathing sewer gas, and it is interesting to recall that
this confirms the conclusion of a former editor of
" Knowledge," Mr. A. C. Ranyard, who, twenty years ago,
wrote an article on the subject in this journal.
November, 1913.
KNOWLEDGE.
429
Mr. Houston also calls attention to the striking differences
between the death-rates from typhoid shown by European
and American cities. This is illustrated by examples of which
the following may be quoted : —
Typhoid
Population.
Death- Rate
per 100,000.
Edinburgh
320,000
1-3
Berlin
2,000,000
2-2
London
7,280,000
3-3
Vienna
2,000,000
3-8
Paris ...
2,750,000
5-6
Boston
670,000
11-3
New York
4,766,883
11-6
Philadelphia
1,549,008
17-5
Washington ...
331,069
23-2
Minneapolis ...
301,408
58-7
In Mr. Houston's opinion the excessive prevalence of
endemic typhoid fever in American cities is probably due to
the "carrier" element, rather than to the consumption of
impure water in the ordinary sense ; since it can be shown by
calculation that an ordinary glass of properly purified water
will probably not contain a single typhoid bacillus.
CHEMISTRY AT THE BRITISH ASSOCIATION.—
Twenty-seven years had passed since a meeting of the British
Association had been held in Birmingham. It was at the
former meeting in 1886 that Sir William Crookes suggested
that the elements might have been evolved from a hypo-
thetical primordial substance or Urthyl. It was therefore
appropriate for the President of the Chemical Section, Dr.
Wynne, to review the progress that has been made in this and
other directions during the last quarter of a century.
With regard to the brilliant hypothesis of Sir William
Crookes, the President pointed out that this common origin of
all the elements was now commonly accepted, although " the
question whether the term ' transmutation ' is verifiable under
available conditions is answered differently according to the
view we take of the disintegration of radium and kindred
phenomena."
The main portion of Dr. Wynne's address, however, was
occupied with a discussion of the chemical change known as
substitution from the point of view of Werner's conception of
valency, according to which an atom may possess both a
principal and an auxiliary or residual valency.
The reports of two committees were presented to the
section, one dealing with " Dynamic Isomerism " and the
other with " The Study of Plant Enzymes." In the latter an
outline is given of the evidence in support of the view that the
pigments in the sap of plants are produced by the oxidation of
a colourless chromogen by means of an oxidising enzyme or
oxydase.
Most of the papers read before the section were of a highly
technical character, and implied a good knowledge of
physical and organic chemistry on the part of the audience.
Of more general interest, however, were the communications
upon radio-active elements. The investigations of Mr. Fleck
during the last year have shown that of the eleven new radio-
active elements studied all, with the exception of Uranium X,
are chemically identical with common elements already
known, such as lead, thallium, and thorium.
In Mr. Soddy's paper upon " The Radio-Elements and the
Periodic Law " the conclusion is drawn that " in that part of
the Periodic Table in which the evolution of the elements is
still proceeding each place is seen to be occupied, not by one
element, but on the average, for the places occupied at all,
by no less than four, the atomic weights of which vary over as
much as eight units. It is impossible to believe that the same
may not be true of the rest of the table, and that each known
element may be a group of non-separable elements occupying
the same place, the atomic weight not being a real constant,
but a mean value, of much less fundamental interest than has
hitherto been supposed."
The communications dealing with applied chemistry
included one upon " The Effect of Impurities on the Quality of
Commercial Copper," by Mr. F. Johnson, and " The Action of
an Alkaline Natural Water on Lead," by Messrs. Liverseege
and Knapp, an outline of which will be given later.
ENGINEERING AND METALLURGICAL.
By T. Stenhouse, B.Sc, A.R.S.M., F.I.C.
CORROSION OF CONDENSER TUBES.— The results
of a long series of experiments carried out with the object of
examining some of the factors which seemed likely to bear
upon the nature and speed of corrosion in condenser tubes
were communicated to the August meeting of the Institute of
Metals by Dr. G. D. Bengough and Mr. R. M. Jones. Tubes
of four standard compositions were immersed in stationary
sea-water at different temperatures, and similar tubes were
used in an experimental condenser plant. The results show
that the temperature is a very important factor in determining
both the nature of the chemical reactions between sea-water
and brass, and also the speed with which the brass is attacked.
Action is much more rapid at higher temperatures and the
experiments demonstrate the bad economy of overloading
condensers. The authors made direct experiments to test the
theory that particles of coke, and so on, deposited in the
tubes give rise to local galvanic action, resulting in pittings,
but could find no evidence of this action taking place. From
their experiments they conclude that selective corrosion,
resulting in dezincification and pitting, is an inherent property
of the alloys examined. They consider that the Admiralty
alloy, copper 70, zinc 29, tin 1, and Muntz's special brass,
copper 70, zinc 28, lead 2, are more suitable for condenser
tubes than plain brass composed of copper 70, zinc 30,
and they recommend the extended use of electro-chemical
protection.
THE CRITICAL POINTS OF STEEL.— A method of
determining the critical points Ar 1 and Ac 1 without the use
of a pyrometer is described by Dr. J. E. Stead in a paper read
before the Iron and Steel Institute at the September meeting.
Two bars of the steel are supported, without touching each
other, in a short length of porcelain tube, which is then
inserted in the side of a muffle furnace. The bars are
allowed to remain until the temperature conditions become
constant, the inner ends of the bars being at a temperature of
about 1000° C, and the outer ends below 700° C. One bar is
then withdrawn for about 15 mm., and the heating continued
for about fifteen minutes more. Thin wires of pure silver,
aluminium, zinc, and so on, are then inserted in the space
between the bars, and the points on the bars where the wires
just melt are ascertained. A scale can thus be plotted showing
the temperature at each point along the bars. The bars are
then withdrawn, quenched, cleaned, and etched, whereby the
line of demarcation between the hard and soft portions
becomes clearly visible. A reference to the scale gives the
temperatures which the bars had at these planes when in the
furnace. The withdrawn bar gives the Ar 1 point, and the
other bar the Ac 1 point. The results obtained in this way
are stated to be within 3° C. of the truth.
GEOGRAPHY.
By A. Stevens, M.A., B.Sc.
THE DISTRIBUTION OF MAN.— The Presidential
Address of Professor H. N. Dickson to Section E (Geography)
of the British Association dealt with the question of the
Redistribution of Mankind, and recently there has been pub-
lished a good deal of matter bearing on the subject. The
discussion of the problem is bound up with the discussion of
resources, but there are certain questions of resources that
are of necessity more or less indefinite and incapable of even
probable solution. Such deal with coal supply, in general and
430
KNOWLEDGE.
November, 1913.
in detail, and with the extent, position, and importance of
supplies of metalliferous minerals. But a matter which is both
fundamental and more definite is the supply of food.
Agriculture has presented to the man of limited capital who
has energy and ambition and the desire to be his own master
in a new country the most attractive if not the only prospect.
The principles underlying his work are these : manual labour,
which is scarce and costly, is the minimum ; the crop covers
a large area, so as to pay in spite of the low yield per acre ;
the ground opened up in the first year is sown and the three
months which elapse before the crop comes to the harvest are
occupied entirely in opening up fresh land for the next spring.
We find Canadian and United States harvests give as low as
twelve to fourteen bushels of wheat per acre, Australian (and
Russian) eight to ten, compared with twenty-eight to thirty-two,
twenty-seven to thirty-three, thirty to thirty-five for the United
Kingdom, Holland, and Belgium respectively (J. F. Unstead,
"The Statistical Study of Wheat," Geographical Journal,
August, September, 1913.)
As the demand for wheat grows, the supply may be
increased, either by increasing the amount of land under
cultivation or by increasing the yield. In certain parts the
amount of suitable land under cultivation has closely
approached the limit of the amount available, and in any case
there is a very definite and reasonably well-ascertained
maximum of such land. In the United States this is already
evident in its effects. (The American Transcontinental
Excursion, 1912, I, " Economic Aspects," by G. G. Chisholm,
Geographical Journal, October, 1913.) Intensive cultiva-
tion is being more and more widely practised, and from the
Western States there is a steady stream of emigration to
Canada, where the amount of unoccupied wheat land is
greater.
It is on account of the great and rapid development of the
means of sea and land transport that certain less crowded
regions have been able to act as granaries for the thickly
populated industrial areas, and this has led to a type of
modern colonisation of a markedly recent and rapid growth.
But the countries originally mainly agricultural are filling up
with an industrial population as new resources are explored
and opened up. The consequence is that home productions
are more and more used at home, and the surplus for export
diminishes. The mean percentage of the total production
of wheat exported from the United States fell from thirty-
two for the period 1881-90 to nineteen for 1901-10. Russia
shows a corresponding fall from twenty-six to twenty-three ;
only newer countries — -Canada, Australia, the Argentine —
show large increases. Generally in a country the obvious
resources are the first used and the first to reach maximum
development, and among these are agricultural resources.
Later developments lead to the growth of an industrial
population. The order seems natural and inevitable, and
Canada and the United States may be taken as types of the
earlier and later stages in the evolution of a country.
Wheat is produced as a rule at a distance, often very great,
from the industrial centres in which it is consumed, and the
cost of transport forms an important if not large part of the
cost of the food. The possibility of local production in any
commodity depends on, among other things, the cost of the
same commodity when imported, and the cost of the home
product is simply the cost of production.* Import and local
production tend therefore to a state of conditional equilibrium,
and the condition may be represented by the formula due to
Professor Dickson (loc. cit.), slightly modified:
/ +l£ E + T,
where / represents cost of local production, E cost of produc-
tion at a distant place, the cost of transport from which is
represented by T. The state of true equilibrium is ideal, and
there will always be an excess on one side of the equation
representing the merchant's profit, and indicating whether
imported goods or local products form the main supply.
Scientific statistical study is extremely important in
Economic Geography. It should be more widely cultivated
because it gives, as it were, a partial differential equation in
which variation is expressed with respect to one variable and
variation with respect to a complex of others is implicit, and
to which a general solution can be found. The essential is
that the study be scientific and rigid. Taking wheat in
production and distribution as the variable, the solution gives
these final results with regard to the redistribution of man :
(a) intensive methods of cultivation will be adopted and lead
to increase in manual labour, and consequently to increase in
density of population in regions mainly agricultural and thinly
populated at present ; (b) cost of food will increase, and this
will result in an alteration of equilibrium in remuneration for
work of all kinds, and in increase of agriculture in countries
now almost wholly industrial ; (c) agricultural and industrial
areas will be more closely intermingled, but there will be no
less centralisation than at present, and nodal towns will tend
to become huge in size.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
CALCAREOUS ALGAE AS ROCK-FORMERS.— This
interesting but neglected subject was taken up by Professor
E. J. Garwood in his Presidential Address to the Geological
Section of the British Association. Whilst examining the
Lower Carboniferous rocks of the North of England, Professor
Garwood was impressed by the abundance of nodular
structures at certain horizons, and the large areas over which
these structures extended. Examined microscopically the
nodules were found to be organic, and to consist largely of the
calcareous alga known as Solenopora. This was the starting
point of an investigation which proved calcareous algae to
play a much more important part in the formation of limestone
deposits than had hitherto been considered. It was also
shown that certain forms became dominant over wide areas
at the same geological period, and might be used as proof of
the general contemporaneity of two deposits. As an example
is cited the abundance of Solenopora compacta during
Llandeilo-Caradoc times over an area covering the Baltic
Provinces, the British Isles, and Canada. The presence of
calcareous algae, which flourish best in the clear, shallow
waters of bays and lagoons, also furnishes evidence as to the
conditions prevailing during the accumulation of the rocks
containing their fossil remains.
THE ENRICHMENT OF SULPHIDE ORES. — The
principle of the secondary enrichment of sulphide ores,
announced almost simultaneously and independently by S. F.
Emmons, W. H. Weed, and C. R. Van Hise in 1900, has
received much discussion in the intervening thirteen years,
and has been made the subject of a bulky Bulletin (No. 529)
of the United States Geological Survey, by W. H. Emmons.
The principle is simple. Under the influence of atmospheric
weathering sulphide ores break down and form soluble
salts, chiefly sulphates. When conditions are favourable
these acid solutions will be carried downwards, generally
along the channels afforded by the fissured zone which
contains the ore-body. The unoxidised rocks below the
ground-water level are in general alkaline, and acid solutions
encountering them in regions where air is excluded will lose
acidity, and certain of the metals they contain will be
precipitated. Also if the solutions of metallic sulphates
encounter sulphides in depth, precipitation of metals may
ensue ; or there may be an interchange between the metals in
solution as sulphates and the metallic sulphides. As a
consequence of these reactions certain parts of the ore-body
* Exception may be taken to the economics of the discussion. In the first place, a (more or less problematical) future position is
considered up to and in which the nature of human (European) food continues as at present, and in which the questions of supply
and demand are somewhat different. For simplicity the matter is taken as less complex than it really is : supply and demand at a
price and changes in mode of living are ignored ; the question of whether land is or is not available does not necessarily arise. The
whole is to be thought of as giving the "differential equation " of the last paragraph.
431
KNOWLEDGE.
November, 1913.
Figure 505.
Chrysanthemum leucanthcmuin
with florets in the disc.
(See Page 409).
Figure 506. Three lightning flashes giving different images.
(See Page 439).
Figure 507. Lightning flashes taken at Johannesburg.
November, 1913.
KNOWLEDGE.
432
Figure 508. Anlacodiscus kittonii, eight rays
Objective used; Zeiss's B.B. of 0-30 N.A. ;
X 375.
Figure 509. Anlacodiscus sp.?, a reproduction
of Figure 411. Volume XXXV, page 372;
X 1,900.
FIGURE 510. Anlacodiscus sp.?, from
which Figure 509 was taUen. Objective
used; Zeiss'sB.B. of 0-50 N.A.; X 375.
Figure 511. Anlacodiscus kittonii,
from the west coast of Africa. Part of
a group of four- and five-rayed forms.
Figure 512. Anlacodiscus kittonii,
four-rayed form. Magnification ;md
objective the same as in Figure 510.
Figure 513. Anlacodiscus kittonii, centre of the
valve, shewn in Figure 508 ; X 1900, the same lens used
as in Figure 514.
Figure 514. Anlacodiscus kittonii, centre of the
valve, shewn in Figure 512. Objective used; Swift and
Son's oil immersion of 1-30 N.A. ; X 1,900.
November, 1913.
KNOWLEDGE.
433
are enriched. The greater part of the metallic contents of
the upper portion of the ore-body which is being subjected to
denudation is carried down in solution, and enriches the
lower portion. Many ore-deposits, especially those of copper,
are leached near the surface, and are considerably enriched
below the leached zone. At still greater depths the ore
becomes of lower grade. The zone of enrichment in a mining
region is frequently found to have a clear relation to the
surface topography, and especially to the ground-water level.
The theory of sulphide enrichment has proved of considerable
economic importance, and has been applied to many deposits
of the metallic sulphides. The subject is of great interest to
chemists as well as to geologists, as is shown by the lengthy
chemical discussion in the above-mentioned bulletin.
METEOROLOGY.
By William Marriott, F.R.Met.Soc.
FISHERY RESEARCH AND METEOROLOGY.— In
the Annual Report on Sea Fisheries for 1912, recently
issued by the Board of Agriculture and Fisheries, reference
is made to the scientific investigations carried out by the
Board. It is stated that although hydrographic data have
been collected systematically since 1903, it must be admitted
that we are still only beginning to arrive at an understanding
of the complicated inter-relations of physical conditions and
abundance or dearth of fish. In many cases, however, it has
already been possible to trace clear indications of a close
connection, not only between hydrographical conditions and
the movements of fish, but between these conditions and
weather. There is a good reason to believe that changes in
the ocean circulation, having a direct effect upon the weather,
greatly influence the growth of trees, and the relation between
atmospheric and hydrographic conditions is not without
interest to the fishing community, both because of the effect
of weather conditions upon actual fishing operations and
because of wind pressure upon the currents of the sea. It is
probable that meteorology has not yet been given its proper
place among the numerous sciences which may contribute to
the proper understanding of the problems connected with
fishing.
THUNDERSTORMS IN EGYPT— Mr. E. W. Bliss in
the Cairo Scientific Journal for June gives some particulars
about thunderstorms in Egypt. A list of all available records
of thunderstorms for the forty-five years 1868 to 1912 was
recently prepared by the Meteorological Service, and a
summary made of the results. For the years 1868 to 1903
the records depend upon the observations made at Abbasia,
but after 1903 they include four storms at Alexandria or else-
where which escaped Cairo. The total number of days
during the period on which thunderstorms, whether slight or
severe, and also cases where lightning only was observed, was
one hundred and eighty. The number of thunderstorms
which were accompanied by hail or heavy rain, or did damage
to buildings, was twenty-eight. It thus appears that there is
an average of rather more than one thunderstorm in two
years.
VOLCANIC DUST AND CLIMATIC CHANGES —
Professor W. J. Humphreys, of the United States Weather
Bureau, in a paper just published in the Bulletin of the
Mount Weather Observatory, has dealt with the subject of
volcanic dust and other factors in the production of climatic
changes and their possible relation to ice ages. Numerous
attempts have been made to find a probable cause for the
known climatic changes of the distant past, and especially
for those profound climate changes that brought about the
extensive glaciation that prevailed during the so-called ice
ages ; but nearly all the older suggestions have been definitely
abandoned because they are inadequate to meet the conditions
imposed upon them by the results of geological investigations.
Professor Humphreys now puts forward the question of
volcanic dust in the upper atmosphere as a factor in the
production of climatic changes, including, possibly, even those
great changes incident to the advance and retreat to maximum
and minimum of glaciation. In his discussion of the subject
he shows, among many other things, that volcanic dust in the
high atmosphere decreases the intensity of solar radiation in
the lower atmosphere, and therefore the average temperature
of the earth ; and this effect has been clearly traced back to
1750, or to the time of the earliest reliable records. It may
consequently be said that such a relation between volcanic dust
in the upper atmosphere and average temperatures of the lower
atmosphere always has obtained, and therefore that volcanic
dust must have been a factor, possibly a very important one,
in the production of many, perhaps all, past climatic changes,
and that through it, at least in part, the world is yet to know
many another climatic change in an irregular but well-nigh
endless series, usually slight, though always important; but
occasionally it may be, as in the past, both profound and
disastrous.
DAILY WEATHER MAPS FOR THE NORTHERN
HEMISPHERE. — The Meteorological Committee in their
Annual Report state that at the beginning of this year Mr.
R. F. Stupart, Director of the Meteorological Service of
Canada, brought to their notice specimens of the charts of
barometric distribution over practically the whole of the
Northern Hemisphere, which are prepared daily in Toronto
by co-operation with the Weather Bureau of Washington.
The charts in question differ from those now prepared in the
Meteorological Office, ten days after date, for issue with the
Weekly Weather Report, by including observations from
Alaska. These are not charted on the Canadian Daily Chart,
which is used for the compilation of the charts in the weekly
report, but it is pointed out that they are of exceptional
importance in relation to the general distribution of weather
conditions.
The Meteorological Committee are informed that the
Russian Government is raising the sum devoted to
meteorology to £50,000 a year, with the object, among others,
of initiating in the year 1915 a service of strictly simultaneous
observations at 6 a.m. and 6 p.m. (Greenwich time) over the
whole of the Russian Empire, which extends over nearly 180°
of longitude. The extension of the ordinary daily working
chart to include practically the whole of the Northern
Hemisphere will then be easily realisable. At this moment
the cable and wireless companies of the world could exchange
information which would give a very fair representation of the
weather conditions of the globe to those who are familiar with
the average features. The realisation of the project of a
" reseau mondial " for the daily weather service is now only a
question of international organisation and of money.
MICROSCOPY.
By F.R.M.S.
ANLACODISCUS KITTONII—AK APOLOGY.— As
author of the articles in " Knowledge " on " The True
Structure of the Diatom Valve," the writer feels an apology is
due from him to the editors and readers of this journal. It is
due to them for his own lapse by making a claim which he
now finds he cannot support, and begs to tender it accordingly.
On page 372, Vol. XXXV, two photo-micrographs were repre-
sented by him as the first published of Anlacodiscus kittonii,
showing the minute details of the structure under an oil-
immersion objective of wide aperture. The statement in itself
was true enough had the photographs but been of that diatom.
Tricked, however, in his memory at the time, he now finds
they were not, and his pretension falls to the ground.
The form then given is still probably a variety. It certainly
is about the same size, has the same general features, plus the
little bosses, but the cellules are much larger ; neither does
the secondary structure offer much difficulty in seeing or
photographing. Such a situation renders the writer's position
somewhat ridiculous, as he feels that he is bound to redeem
his character somehow, and, after assuming the white sheet,
now makes the attempt upon a form there can be no mistaking.
The photo-micrographs of the whole valves, taken for this
article, are magnified three hundred and seventy-five times.
Looking at the minuteness of the cellules in the two normal
434
KNOWLEDGE.
November, 1913.
forms, even under this magnification, it will be seen at once
how difficult is the task of photographing the still more minute
secondary structure— six or more faint dots within each cellule.
Nothing is more fitted to try the worker's mettle ; indeed, one
may say from one's experience in diatom structure, nothing
else is so fitted. There still remains to try the mettle of the
process worker and others in preparing the blocks.
The drawing of the finer structure of this diatom by Messrs.
Nelson and Karop, published in The Journal of the Quekett
Club for 1887, shows a few cellules only. Although professedly
drawn to a scale of one thousand two hundred diameters,
each cellule appears as of twice the sue of those in the present
prints, taken at one thousand nine hundred. One can question
neither the good faith of the artist nor the real size of the
details in the valve, yet the discrepancy can be easily accounted
for by supposing that Mr. Karop found them almost impossible
to make plain to the eye on so small a scale. This is the
difficulty the present writer fears now in his own prints, though
trusting to the skill of all connected with the production of
" Knowledge."
In the drawing in question the six or seven dots within each
cellule are rendered quite pale, a characteristic feature of this
diatom, and one making them so difficult to photograph. The
boundaries are formed by a series of similar dots, but black.
One does not like to differ from such eminent observers
as Messrs. Nelson and Karop, at the same time one
cannot help feeling that they are due to interference
from the under-structure of hexagons. Something of like
appearance occurs in Figure 513 of the present article,
yet on using the largest aperture of the substage con-
denser they disappear and the dotted membrane is seen
to be continuous over the whole valve. There would be
work for the owners of oil immersions during the winter
months to solve this problem and then send the results to
" Knowledge " — with the consent of the editors, of course.
The evidence of a continuous membrane is not lacking in some
of the coarser discoid forms. We have already seen that in
Triceratium favus and Coscinodiscus asteromphalus there
are structureless parts from which the kind of woven material
forming the secondary structure springs. In one species of
Coscinodiscus, however, from the Nottingham deposit, there is
nothing of this ; instead a uniform perforated membrane,
stuck upon little bosses some distance above the hexagons,
spreads over the whole valve.
Coming to the figures now, Figure 510 is of the same valve
from which Figure 411 of the last article was taken at one
thousand nine hundred diameters. Unfortunately the par-
ticulars underneath the print say two thousand seven hundred
and fifty, but this is a mistake. In some manner the
particulars of four hundred and ten and four hundred and
eleven have become transposed. Figure 410 should read
two thousand seven hundred and fifty diameters and 411
nineteen hundred. The next, Figure 512, is from an
undoubted four-rayed normal form of A. kittonii, and it will
be seen at once how minute are the cellules as compared with
Figure 510. Figure 514, taken at one thousand nine hundred
diameters from the centre of the same valve, shows the
secondary structure, but so minute as almost to require
another lens to see it. In Figure 509 we go back to Figure
411 of volume XXXV in order to compare the size of the
cellules with Figure 514. The contrast between the two will
then speak for itself.
Figure 508 is from an eight-rayed valve, a very beautiful
variety. A photo-micrograph of the same variety of this
species appears in the two editions of the Dallinger-Carpenter,
taken at two hundred and seventy diameters, by Mr. E. M.
Nelson, with an inch objective under dark-ground illumination.
Seen on either the first or second plate it looks innocent
enough, until one attempts the same performance with an inch
objective. Believe one who has tried, and must confess
to a dismal failure or failures in consequence. Figure 513
is from the centre of Figure 508, which, with Figure 514,
the writer hopes may be taken as a fitting supplement to Mr.
Nelson's print. He hopes also that he has now made his
amende honorable, as really having done what he only
boasted of doing before.
The varieties of A. kittonii range from three rays to nine.
The centre valve in Figure 511 is a five-rayed form, and is
curious otherwise as showing that Nature's freaks, such as
Two-headed Nightingales and Siamese Twins, are not con-
fined to complex organisms. At the end of each process in
the normal form, under high powers, a little bulb of crystal can
be seen, in shape like those used to light the carriages in the
tube railways. They are just indicated in the print, but at
the end of one process two appear in place of the usual one.
The specimens in this mount are from the west coast of
Africa. Ten in number consist of the four-rayed forms, one
of five, yet the secondary structure is so minute as not to offer
the slightest signs of resolution under an aperture of 1 • 30
N.A. Notice also the different shape of the processes from
Figures 512 and 508.
PHOTOGRAPHY.
By Edgar Senior.
GLAZING SILVER PRINTS.— When it is desired to
impart a high degree of glaze to P.O. P. or bromide prints
whcih are made upon a glazed surface paper, the prints after
washing should be placed in a solution of some hardening
substance, such as ordinary alum, chrome alum, or formalin.
Especially in warm weather is this treatment necessary, since
the gelatine surface often becomes very soft and liable to
adhere to the surface used for squeegeeing upon, whatever
precautions may have been taken to avoid it. If alum is
employed as the hardening agent a five per cent solution
should be employed ; formalin, however, is to be preferred in
many respects, as alum is not always successful in its action.
The strength of the formalin solution should be about one
ounce to ten or twenty ounces of water, and the prints should
be allowed to remain in for five or ten minutes and then
washed in several changes of water. With regard to the
materials to be used for squeezing the prints upon, these may
be either glass, ferrotype plates, or celluloid, the latter two
being the least likely to give trouble from the prints sticking.
If glass be used it requires to be very thoroughly cleaned, and
must be soaked for some hours in either of the following : —
Nitric acid 5 ounces
Water 20
or
Potassium bichromate ... 1 ounce
Water 30 ounces
Sulphuric acid ... ... 1 ounce
The bichromate should be dissolved and the solution made
perfectly cold before the sulphuric acid is added, this latter
being introduced very gradually, stirring well all the time.
As this mixture is very corrosive, great care is required in
handling it. After the glass plates have been soaked for
several hours, they should be well washed in water and
allowed to dry, when they are polished with French chalk, this
being dusted on to the plate and well rubbed over and
finally dusted off again. Or in place of the French chalk a
solution of beeswax in benzol or turpentine may be applied
with a piece of rag or a tuft of cotton-wool, and the surface
afterwards polished with a clean cloth. The following formula
will give a good solution for the purpose : —
Beeswax 15 grains
Turpentine 1 ounce
The clean glass, ferrotype plate, or celluloid should have a
little of this well rubbed over the surface and then polished
off. The material being ready, the prints are taken from the
washing water and laid face downwards, and then squeegeed
into contact and allowed to become thoroughly dry before any
attempt is made to strip them, and on no account must the
drying be at all accelerated by heat, or the prints will be
difficult to remove from the support. Sometimes difficulty is
experienced in getting them off, but this can be prevented by
drying the prints first and then rewetting them ; and if care be
taken to have the surface of the material thoroughly well
cleaned and prepared the prints should almost leave by them-
selves, especially so when ferrotype plates are used.
November, 1913.
KNOWLEDGE.
435
PHYSICS.
By Alfred C. Egerton, B.Sc.
A SENSITIVE PRESSURE GAUGE. — M. Gueritot
publishes in the Comptes Rendus for June, 1913, an account
of a sensitive manoscope which employs thermo-electric
junctions to detect very small displacements of air. Two
vessels are connected by a tube which is bent in the middle
upwards ; the tube is heated at the point of the bend
electrically, and the heated air remains in the neighbourhood
of the bend. On each side of the heated portion of this tube
are inserted two junctions of dissimilar metals connected to a
galvanometer. Any displacement of the heated air causes a
difference of temperature between the two thermal junctions,
and consequently an electromotive force is set up which drives
a current through a galvanometer. Very small displacements
of the heated air can be measured ; in fact, variation of
atmospheric pressure by one millionth of a millimetre of
mercury can be detected.
NEON AND X3. — Among the most interesting announce-
ments at the Birmingham meeting of the British Association
may be mentioned the experiments of F. W. Aston on the
separation of neon by diffusion into two constituents possessing
atomic weights very nearly the same, confirming in a remark-
able way the positive-ray experiments of Sir J. J. Thomson,
which showed that neon should contain two substances of
very nearly the same atomic weight. The other announcement
was by Sir J. J. Thomson about the supposed new gas, Xa.
The atoms of a gas of atomic weight 3 had been identified
by his positive-ray method. The properties of this gas have
been recently studied by Sir J. J. Thomson, and he was able to
announce that it behaved as a gas with a molecule consisting
of three hydrogen atoms. Thus hydrogen, as well as oxygen,
can give rise, under the action of electric discharge, to a
molecule consisting of three atoms. The molecule of active
nitrogen, discovered by Strutt, on the other hand, is supposed
to consist of single atoms.
Section A of the British Association at Birmingham showed
great activity, amongst the most interesting of the discussions
being that on " Radiation."
ZOOLOGY.
By Professor J. Arthur Thomson, M.A., LL.D.
POISON OF AMPHIBIAN SKIN.— It is well known that
the defenceless Amphibians — toads, frogs, newts, salamanders,
and the like — are protected by a poisonous secretion formed
by skin glands. The phrynin of the toad has been often
experimented with, and is a powerful poison. Madame
Phisalix has recently found that injections of a modification
of Amphibian poison will immunise an animal, e.g., rabbit or
guinea-pig, against a strong dose of the same poison. This is
what might have been expected from analogous cases. But
the further point is of much interest— that animals immunised
against Amphibian poison are also immunised against the
poison of the viper.
BEHAVIOUR OF FAIRY SHRIMPS.— Professor A. S.
Pearse, of the University of Wisconsin, has made an interest-
ing study of the behaviour of Eubranchipus dadayi, one of
the fairy shrimps. Its movements are exceedingly easy
and graceful. The body glides through the water slowly
but steadily at the rate of about a foot in ten seconds, with
the ventral surface usually uppermost or towards the light.
There is considerable dimorphism between the sexes and a
difference in colour that is of considerable interest. The
males have a delicate, translucent, almost transparent, creamy
colour, with reddish tail-pieces, while the females are reddish
throughout. The transparency of the males enables them
to wander about with comparatively little danger of being
seen, and they are thus able to seek out and fertilise the
females. On the other hand the coloration of the females
makes them inconspicuous as they rest quietly in holes at
the bottom of the pool, or await a mate at the surface in the
shadow of some floating stick or other shelter. Professor
Pearse's point is that "the coloration of each sex is
apparently adjusted to its behaviour in such a way that it is
well protected." The males have a strong sexual appetite,
but as soon as a female has been provided with sperm she
resists the advances of males, goes to the bottom of the pond
in which she lives, and remains quiescent so that the eggs
may descend into the ventral part of her ovisac, undergo
fertilisation, and develop.
RACES OF SARDINE.— Louis Fage has made a study
of the growth of the Sardine or Pilchard (Clupea pilchardus),
using the method, now so much employed, of reading the age
from the scales and otoliths. As in other cases, the concentric
striated zones seen on a scale are interrupted by several
clear non-striated zones, the latter indicating periods of rest
("winter rings"). As Hjort has said, "the growth of the
scales is so closely bound up with that of the individual that
it is possible by simple measurements of the zones of growth
on the scale to retrace with real precision the history of the
growth of the fish." The results of his measurements lead
Fage to conclude that there are two distinct "biological
races " — the Mediterranean and the oceanic Sardine. The
former grows more slowly, and lags more and more behind
as it grows older. He proposes to study the structural
differences associated with this different rate of growth.
SIGNALLING AMONG TERMITES.— Professor E.
Bugnion, of Lausanne (MT. Schweiz. Entomolog. Gesell-
schaft, XIII, 1913, page 125) communicates some very
interesting observations on signalling among Termites. The
phenomenon has been previously studied by Konig, Smeath-
man, Haviland, Sjbstedt, and Escherich, but Bugnion has gone
further. Helped by H. von Buttel-Reepen, he found that the
noise is produced by the soldiers, who knock on dry leaves or
the like with their mandibles, or with the basal piece of the
labium, which is exaggerated and hard. A cobra-like hissing,
as it seemed at first, was traced to a colony of Tertnes
obscuriceps which had formed its galleries on the big fallen
leaves of the Bread Tree (Artocarpus). From a colony in
Bugnion's office-desk answers used to be got to outside taps.
In another experiment a piece of termitary was placed on a
big plate and covered with stiff paper ; the soldiers collected
on the under surface of the paper and answered back to every
vibration. The noise differs in different species, but is always
due to minute blows on a resonating surface. The result
may be a rustling, or a rattling, or a crackling, or otherwise.
In the Indian Tertnes estherae Desneux, which turns out to be
the same as KSnig's Hodotertnes convulsionarius, the noise
made by the large and aggressive workers when they are dis-
turbed is like the crackling of withered leaves trodden underfoot.
There is evidence that the noises or the associated vibrations
serve to warn the workers or to reassure and encourage them.
There seems little doubt that they are of the nature of signals.
That sounds or vibrations are really perceived is made clear by
what was seen in the field, by the responses given by the
tenants of Bugnion's desk to taps from without, and by the
anatomical demonstration of a well-innervated sensory organ,
which is probably particularly sensitive to the vibrations of a
material like the framework of a leaf or branch, the wooden
partitions of the termitary, the dry walls of the fungus-growing
labyrinths, and so on. It is too soon to ask how much is
auditory and how much finely tactile. The audible signalling
is to be distinguished from another kind of signalling — a
soundless signalling — which seems to be common among
Termites. It is curiously like and unlike military saluting ;
for it seems that the soldiers salute the workers. So far as
we know, both soldiers and workers are sexually immature
individuals of both sexes. But this requires looking into. In
the soundless signalling the insect stands firmly on its legs,
with the head raised and the body slightly oblique, and shakes
itself for an instant with a convulsive shiver. This seems to
mean something to the passing worker. We cannot get
psychologically near enough to say more.
THE FACE OF THE SKY FOR DECEMBER.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 82.
Date.
Greenwich
Noon.
Dec. i
„ 6
,, II
„ i°
, 21
„ 26
M 3*
Sun.
R.A. Dec.
h. in. o
16 27"9 S.21'8
1 6 49*6 22*5
17 n'6
17 33'°
17 55*8
18 i8'o
23*0
23*3
23 '4
23*4
18 40'2 S.23'I
Moon.
R.A. De
h. m. e
19 38-6 S. 25*9
23 34*8 S. 2-4
3 19-9 N.23-o
8 11*9 N.23'9
12 33-1 S. 5*6
17 14*7 S. 28*1
21 52*2 S. 15*0
Mercury.
R.A. Dec.
h. m.
15 24-2
15 28-4
»S 44 '9
16 8-5
16 36'i
17 *"3
S. i6"o
16 '2
i7'5
•*9*3
21*0
22*5
17 38*2 S.23'6
Venus.
R.A. Dec.
h. m. o
15 T7'i S.i7'o
15 42'5 i8'7
16 8*4 20"2
16 34*8 21*4
17 1 "6 22*3
17 28 '7 23 "o
17 56*oS.23-4
Mars.
R.A. De
7 47'3N.23-8
7 45 '3 24' t
7 4- -8
7 36-8
7 3°'5
7 23*0
7 i4*6N.26"2
24 '5
24-9
25*3
Jupiter.
R.A. Dec
h. m.
19 20M
19 24*6
19 29'!
19 33'8
19 38*6
9 43*4
S.22'5
22*4
22*2
22 'O
21 '9
21*7
19 48-3 S.2I*5
Saturn.
R.A. Dec.
h. m. a
4 56*4 N.2o"g
4 54-6 20 *9
4 52 "9 20 "8
4 51*1 20*8
4 49*4 20'7
4 47*8 207
4 46'3 N.2o*7
Neptune.
R.A. Dec.
h. m.
59*9
59 "6
59*2
58-7
58-2
57*7
N.20'I
20 '2
20*2
20*2
20*2
20 "2
N.20"3
Table 83.
Date.
Sun.
P B L
Moon.
P
Mars.
P B L T
Jupiter.
P B I. I. T T
121 2
Greenwich
Noon.
o 0 o
+ i6'2 +o*7 277-0
I4'2 +0*1 2II'I
WO -O'S I45'3
g-8 12 79-4
7'4 1 '8 13-5
S'° 2-4 3077
+ 2'6 — 3'o 241*8
0
- 8-8
-2i-8
-14-2
+ II-5
+21-8
+ 4'5
-i8'4
0 0 oh. m.
— i2'o H-o*7 98*1 5 17 w
™"3 9"3 53'o 8 23 m
I2'8 8-7 8'2 11 j6m
13-4 8-i 323-7 2 29 «
•4'3 7'3 279-5 s 3o(
15-3 6-4 235-5 8 30 «
-16-4 +5-5 1917 11 30c
0 0 ' ' h. m. h. m.
- 9'3 — «'3 345'2 H3'1 10 1 « 8 53 m
9'7 i'3 62-4 143-2 10 iSw 5 59*
io*2 1-2 130-6 173*3 8 26 tn 7 13 in
io*6 1*2 198*8 203-4 4 25 e 4 19 e
— il'i i'2 267-0 233-4 4 42 wi 3 30 c
„ 6
„ i5
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Mars, T is the time of
passage of Fastigium Aryn across the centre of the disc. In the case of Jupiter, Lt refers to the equatorial zone; L2 to
the temperate zones; Tlt T2 are the times of passage of the two zero meridians across the centre of the disc ; to find inter-
mediate passages apply multiples of 9h 50£m, 9h 552m respectively.
The letters tn, e, stand for morning, evening. The day is taken as beginning at midnight.
The asterisk indicates the day following that given in the date column.
The Sun reaches its greatest South Declination (Winter
Solstice) December 22d 10ih tn. Its semi-diameter increases
from 16' 15" to 16' 17-J". Sunrise changes from 7h 46m to
8h 8m ; sunset from 3h 52m to 3h 58m.
Mercury is an evening star; reaches elongation, 21° W.,
on 10th, H° N. of Venus, 2d 8h e. Semi-diameter diminishes
from 4" to 2£". Fraction of disc illuminated increases from
k to a.
Venus is a morning star, but getting too near the Sun
for convenient observation. Disc practically full. Semi-
diameter 5".
The Moon.— First Quarter 5d 2" 59m e; Full 13d 3" 0me ;
Last Quarter 20d 4h 16m e. New 27d 2h 59m e. Apogee
6d 11" e. Perigee 21d 2h e, semi-diameter 14' 48", 16' 10"
respectively. Maximum Librations, ld 6° W, 13d 5° E,
13d 6° S., 26d 6° N, 28d 5° W. The letters indicate the
region of the Moon's limb brought into view by libration.
E. W. are with reference to our sky, not as they would
appear to an observer on the Moon. (See Table 85.)
Mars rapidly approaches opposition. Nearest Earth on
January 1st, distance 0-622. This is an unfavourable
opposition as regards distance, but favourable as regards
planet's declination. It will be seen that both hemispheres of
Mars are observable, but the Northern one is best placed.
The semi-diameter during December increases from 6l" to 7-J-".
The unilluminated lune is on the West: its width diminishes
from I" to 0.
Jupiter is an evening star, but almost invisible. Polar
semi-diameter, 15i".
Table 84.
1
Day.
West.
East. I
)ay.
West.
East.
Dec. I
21
c
43 D<
c.13
31
O
24
>■ 2
c
4123
. 14
32
0
14
.. 3
4
c
23 !•
. IS
21
0
34
■> 4
4231
c
, 16
0
134
.. 5
43
c
1 -■•
, 17
1
0
234
„ 6
431
0
2
, 18
23
0
14
.. 7
423
c
1
. 19
32
0
i*
„ 8
421
0
3
, 20
341
0
2
•• 9
4
G
123
, 21
43
0
1
„ IO
41
c
23
1 22
421
0
3
,. "
23
G
1 4
. 23
4
0
213
M I2
32
0
14
, 24
41
0
23
Configuration at 5h e for an inverting telescope.
Satellite phenomena visible at Greenwich, 2d 6h 27m IV. Tr.
I.j 3d 4" 54
lld4h 15m
14a 4*1 4411
Sh. I. These are all in the evening hours. The reappearance
from eclipse takes place on the east of the disc, to the right in
an inverting telescope.
r
I. Oc
D.
;4d
4'
32m
I. Tr. E.
; 5h
20,n
I.
Sh.
E.;
1.
Tr. I.
,4h
56m
I.
Sh. I
.; 12d4'
22m 15s
I.
Ec.
R.;
1
. Sh.
E.;
18d
4'
30m
III. Tr.
E.;
21d
4h
26m II.
436
November, 1913.
KNOWLEDGE.
Table 85. Occultations of stars by the Moon visible at Greenwich.
437
Date.
Star's Name.
Magnitude.
Disappearance.
Reappearance.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.
'9r3-
h. m.
h. m.
Dec. s
h1 Aquarii
S-4
3 4'
114°
3 44'
176°
„ 8 ...
BD+ c/142
7-1
5 42 '
105
—
—
„ 10
BD + i8°347
69
4 55'
131
—
—
,, 10
BD+ir/432
7-0
9 7 '
56
—
—
,, 10
47 Arietis
S-8
11 49 e
140
0 i5*>«
181
„ 11
9 Tauri ...
67
3 5o '
87
—
—
„ 11
16 Tauri ...
S'4
8 15 e
14
9 2 e
299
„ 11
17 Tauri
3-8
7 53'
59
9 8e
254
„ 11
20 Tauri
4'i
8 47'
22
9 41 '
293
» "
23 Tauri
4'3
8 57*
144
9 16 e
173
„ II
24 Tauri
68
9 20(
"3
—
,, II
BD + 23°540
7-0
9 24 e
74
—
—
,, II
r/ Tauri ..
3'°
9 29 e
121
10 18 e
198
,, II
BAG 1171
6-6
9 59'
82
—
—
.. 13
BAC 1746
6-5
5 56 e
80
6 54'
259
,. 14
BAC 1848
5-6
1 19 m
99
2 33 >"
269
,, 14
BAC 1918
6-i
6 1 1 m
128
6 58 m
248
„ 14
BD + 27°ii64
69
—
—
6 53'
263
,, 14
BD + 27°ii94
77
—
—
8 42 e
194
., 16 ...
7 Cancri
4-8
9 38 «
45
10 11 e
343
„ 17
BD + 20°2232
69
—
—
4 10 m
208
„ 17
8 Leonis
5 9
8 57'
76
9 45'
320
„ 20
82 Leonis ...
67
—
—
0 33 >"
323
„ 20
83 Leonis
63
0 20 m
122
1 21 m
299
,, 20
t Leonis
5-2
0 55 m
121
I 58 m
303
„ 21
BAC 4172
6-6
— ■
—
5 21 m
279
,, 22
BD-io°363S
69
—
—
5 24 m
326
., 31
1 Aquarii
4 '4
5 45'
359
6 24 e.
291
From New to Full disappearances take place at the Dark Limb, from Full to New reappearances.
The asterisk indicates the day following that given in the date column. Attention is called to the occultation of the Pleiades, on
Dec. 11th, the Moon being 2 days before Full.
Saturn is very well placed for observation, being in
opposition on the 7th. Polar semi-diameter 9J". P. is
— 4°-4; B — 26°-4. Ring major axis 48", minor 21". The ring
is approaching its maximum opening, and projects beyond the
poles of the planet. It is interesting to measure the exact
amount of overlap.
East Elongations of Tethys (every fourth given), ld 10h,lw,
8d llh-2e, 16" 0h-4e, 24d lh-5w, 31d 2h-7e; Dione (every
third given), 6d 6h-2m, 14d ll"-lm, 22d 4h-le, 30d 9k-le;
Rhea (every second given), 6d 0h-9m, 15d lb-5m, 24J 2h-2«J.
For Titan and Iapetus E.W. mean East and West Elonga-
tions; I. Inferior (North) Conjunctions, S. Superior (South)
ones. Titan, 2d llh -8m E.; 7d lh-7m I., 12d 9h-8e W.,
18d10h-3e S., 23d4"-le E., 28d6h-2m I.; Iapetus, 17d 9h-l*»
Uranus is an evening star, but badly placed.
Neptune is a morning star, in Cancer.
Meteor Showers (from Mr. Denning's List) :-
Radiant.
Date.
R.A. Dec.
Nov. 25 to
O 0
189 + 73
Rather swift.
Dec. 12
Dec. 4
162 + 58
Swift, streaks.
,, 6
80 + 23
Slow, bright.
„ 8
145 + 7
Swift, streaks.
„ 8
208 + 71
Rather swift.
„ 10-12 ...
108 + 33
Swift, short, conspicuous.
,, 12
119 + 29
Rather swift.
,, 22
194 + 67
Swift streaks.
,, 21-22 ...
117 + 47
Swift.
„ 31
92 + 57
Slow, bright.
Westphal's Comet. — The following ephemeris covers the
whole time over which the comet is likely to be visible with
ordinary telescopes : it is likely to be a faint naked-eye object
•in November. The ephemeris is for midnight on the dates
named.
Date.
R. A.
N. Dec.
Log. Dist.
from Sun.
Log Dist.
from Earth.
H.
M.
s.
Oct. 20
20
53
39
17
4
01358
9.8141
,, 24 ...
20
47
24
19
53
01287
9.8271
,, 28 ...
20
42
27
22
3°
01225
9.8409
Nov. 1
20
38
3°
24
56
01 169
9-8547
.- 5 ••
20
3.5
26
27
22
01119
9.8682
,, 9 ■•■
20
33
24
29
40
01075
9.8809
,, 13 ■••
20
32
8
3'
53
01 038
9.8932
„ 17 ■■■
20
31
51
34
8
0-1014
9.9050
„ 21
20
32
28
36
20
01004
9.9163
„ 25 ...
20
33
54
38
25
O-IOOO
9.9266
,, 29 ..
20
35
56
40
27
01004
9.9361
Dec. 3 ...
20
38
16
42
33
OIOII
9.9444
„ 7 •••
20
41
24
44
41
01028
9.9519
„ 11
20
45
52
4b
49
01062
9.9594
„ 15
20
5'
8
49
0
01 103
9.9662
„ 19 ...
20
57
32
51
9
01 149
9.9727
„ 23 ...
21
5
4
SI
21
o- 1 206
9.9786
,, 27
21
14
0
55
38
01 268
9.9847
„ 3' ■■
21
24
48
57
50
01332
9.9907
Jan. 4
21
37
0
60
17
0-1402
9.9964
„ 8 ...
21
52
8
62
29
01483
0.0026
„ 12
22
9
56
64
44
01565
0.0087
,, 16 ...
22
3«
28
66
59
01652
0.0154
,, 20
22
55
16
68
57
01 740
0.0231
,, 24 ...
2,3
29
0
70
37
01826
0.0315
„ 28 ...
O
S
56
72
12
0-1918
0.0400
Feb. I
O
48
36
73
14
0-2012
0.0500
The path lies through Vulpecula, Cygnus, Cepheus, and
Cassiopeia.
438
KNOWLEDGE.
November, 1913.
Double Stars and Clusters. — The tables of these referred to the corresponding month of last year,
given last year are again available, and readers are Variable Stars.
Table 86. Non-Algol Stars.
Star.
Right Ascension.
Declination.
Magnitudes.
Period.
Date of Maximum.
h. m.
0
d.
R Arietis
2 II
+ 24 -7
7-5 to 127
186-66
Sep. 12.
R Ceti
2 22
-o-6
7-5 to 128
166-88
Oct. 20.
U Ceti
2 30
-13 -5
66 to 12- 7
235-2
Dec. 8.
R Trianguli ...
2 32
+ 33 -9
5.9 to II- 1
265-4
Dec. 27.
Y Persei
3 22
+ 43 '9
8'2 to 104
254' 9
Nov. 2.
R Tauri
4 24
+ 10 -o
7-410 13- 8
325
Dec. 10.
X Camelop
4 35
+ 75 'o
7-510 13
141-5
Nov. 18.
T Leporis
5 '
— 22-0
7-7 to 8-9
366-5
Dec. 6.
S Camelop
5 32
+ 68 -7
7-8 to io-8
33°
Dec. 20.
Principal Minima of /3 Lyrae Dec. 4d lhe, 17d llhm, 30d 9h m. Period 12d 21h -8.
Algol minima Dec. 3d 6h 18me, 6d 3h7rae, 15" 5h 34™»j, 18d 2h23mm, 20' 11" llme, 23d 8h 0me, 26d 4h 49me. Period 2d 20h -8.
SOLAR DISTURBANCES DURING SEPTEMBER, 1913
By FRANK C. DENNETT.
September has yielded very little appearance of activity
upon the Sun to the ordinary telescopic observer, although to
the spectroscopist there does seem to be some increase. No
observations were made on two days during the month (1st
and 5th), spots were recorded on six days (6th to 10th and
16th), and faculae on nine others (3rd, 14th, and 24th till 30th).
On the remaining thirteen days the disc appeared clear. On
September 1st the Central Meridian was 37° 27' at noon.
No. 11. — So late as 10 a.m. on September 6th the disc was
reported clear, but at 1.20 p.m. a small irregular penumbraless
spot was recorded. On the 7th it had four or five smaller
companions, some bridged over, hydrogen flocculi were lying
about the area, causing displacements of the C-line, first to
red and later to violet. On the 8th the leading spot had
increased somewhat, and a trailer spot with small companions
had developed. Prominences were seen in projection over
the group, as well as dark hydrogen flocculi. On the 9th only
some members of the leading group visible, edged with
brightness, and on the 10th, at 8 a.m., just one pore was left
amidst the group of faculae which marked the area ; but it was
gone by midday. The group reached a length of 45,000 miles
on the 8th. The dark line of helium, D3, was traceable over
this disturbance on the 7th, 8th, and 10th.
On the 16th, at 8 a.m., there appeared to be traces of pores
on several parts of the disc, the largest being in South latitude
some two days past the central meridian, and therefore near
longitude 227°.
Faculae were seen near the eastern limb, well to the north,
on the 3rd ; on the 7th a small facula near longitude 258°
and 60° N. latitude ; on the 14th several bright flecks
appeared scattered over the disc. Faculic flecks were persist-
ently visible in the region within 20° of the north pole, records
being made on the 24th and 27th to 30th ; a faculic region
over, and just ahead of, the area of No. 11, within the eastern
limb, seen from the 25th until the 27th.
The observers whose work has contributed to this note
have been Messrs. J. McHarg, A. A. Buss, C. Frooms,
E. E. Peacock, and the writer.
DAY OF SEPTEMBER, 1913
. 50.
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SO 100 110 120 BO 140 ISO (0 170 180 190 ZM W 220 230 »0 250 260 270 280 290 500 310 320 330 340 350 360
CORRESPONDENCE.
LIGHTNING FLASHES.
To the Editors of " Knowledge."
a most vigorous but short-lived thunderstorm developed some
distance to the north-west of Johannesburg. The flashes of
lightning, which were principally cloud-earth discharges, were
Sirs,— During the evening of Tuesday, December 5th, 1911, very brilliant, and followed one another at short intervals. I
November, 1913.
KNOWLEDGE.
439
had a whole-plate Sanderson camera practically ready for
action, and set this up on the stoep of my house (facing
northwards) as quickly as possible. As I had a focal-plane
back on the camera, I opened the slit to the width of the
plate and decided to expose by withdrawing the slide of the
plate-holder, the lens cap not being at hand. Generally in
photographing lightning one has to wait for a little time to
secure a good flash, but on this occasion there were a number
of bright flashes whilst I was in the act of withdrawing the
slide. The bright flash to the right of the centre of
Figure 507 was the first to occur. At the moment I was not
certain whether the flash was too early for me. It was
followed almost immediately by the great flash which appears
on the left of the picture, and on seeing this I closed the
plate-holder at once. The plate was exposed at 7.45 p.m.,
and was developed at 8.5 p.m. on the same evening. The
centre flash is seen to be multiple, showing six or seven
discharges. The displacement of the individual flashes is due
to the fact that the flash occurred whilst I was withdrawing
the plate and the camera was oscillating slightly. The large
flash on the left of the picture also shows a similar effect.
This flash was much nearer to the camera than the two
flashes near the middle of the picture ; the latter are beyond
a low cloud, whereas the former is in front of this cloud.
The successive strips into which the negative is divided
puzzled me whilst the plate was developing, but the explana-
tion soon suggested itself. They represent flashes which
occurred during the short interval occupied in opening (and
possibly also closing) the plate-holder, which were not in the
field of view of the camera, but were near enough to produce
a fogging effect. The time taken for the double operation of
opening and closing the dark slide I found was nearly three
seconds, and in this interval there were at least twelve flashes.
Another plate was exposed at 7.50 p.m. on the same even-
ing, and as the storm was then much more distant the camera
was left open for some time. On developing, three small
flashes were seen to have impressed themselves (see Figure
506) and, very strangely, they were all photographically
different, i.e., one gave a normal image, the second a reversed
image, and the third a re-reversed or solarised image.
H. E. WOOD (F.R.Met.S.).
Transvaal Observatory. Johannesburg.
MARS.
To the Editors of " Knowledge."
Sirs, — In your issue of August, there appeared a letter from
M. Antoniadi with reference to a letter of mine which appeared
in your June issue. In discussing the questions arising from
these letters, I will endeavour as far as possible to dispense
with arguments ad hominem, and confine myself to arguments
ad rem.
M. Antoniadi declares that I misunderstood the purpose of
his article in the May issue of your journal (" Considerations on
the Physical Appearance of the Planet Mars," pages 193-196).
If my interpretation of this article (which is set out in my
letter in your issue of June) is incorrect, I had ample excuse for
being mistaken. The scorn which in this article M. Antoniadi
pours on those who are not of his way of thinking would, I
think, justify anyone in supposing that he claimed that his
views held the field in science. The motive which led me to
criticise M. Antoniadi's article was not an anxiety to contra-
dict, but a desire to point out to the uninitiated reader that his
views are by no means universally accepted by men of science.
I am satisfied on the not very important point that there
are instances where the canals have been represented out of
perspective. Taking into consideration the extreme delicacy
of these objects, and indeed they are so delicate as to require
the most favourable conditions for observation, and even in
the fine air at Flagstaff a disturbed atmosphere at times blurs
them out of recognition, it is not surprising that errors of
this nature occasionally occur.
M. Antoniadi seems to have altogether failed to understand
my meaning when I showed (I hope satisfactorily) that it is
not legitimate under any circumstances to represent as
indistinct and vague an object which is seen as clear and
defined. It is quite possible that if the image of Mars in the
telescope could be so enlarged that with perfect definition it
appeared the same size as a drawing three inches in diameter
held at a distance of one foot, features which under ordinary
circumstances appear sharp might appear exceedingly vague
and undefined. But, on the other hand, it is also possible
that they would appear as sharp and defined as they actually
do under ordinary circumstances, with the possible addition
of smaller canalian features. This is a question which
cannot at present be decided. M. Antoniadi's analogy
of a sixpence is a false one. It is true that if a six-
pence (or almost any other artificial production) is greatly
enlarged its details become vague. This, however, is not
true of most objects of nature, in many cases the original
details remaining sharp and well defined, and finer features
coming into view. If a sixpence were struck of the size of
three inches, all the details being perfectly defined, and then
reduced to the size of an ordinary sixpence, an enlargement
of it to its original size would not show the details vague. It
is thus impossible to ascertain without experiment what the
appearance of an object will be on enlargement. In recording
observations by drawings it is therefore only legitimate to
draw exactly what one sees, and it is not legitimate to make a
drawing showing what one thinks the planet's appearance
would be if it could be seen as large as the drawing. Such a
method is drawing beyond one's vision.
Then with regard to photography. In the perception of
light and shade contrast the camera is superior to the eye.
Hence the great value of the camera in the perception of faint
stars and strands of nebulosity and of the light and dark areas
of the planet Mars. But it must be admitted that for the
perception of fine, sharp detail the camera is not as efficient
as the eye. Far more detail has been seen on the moon than
has ever been photographed. Poor would be the observer
who could see on the moon no more detail than appears on
the very finest lunar photographs. In the Martian photographs
all the finer detail of the planet's marking is blurred almost
out of recognition. It is claimed, however, that canals are
indicated even on photographs. It is noticeable that the
photograph of Mars given on page 194 in your May issue
shows almost as much detail as does M. Antoniadi's drawing
of the same region. For light and shade studies of the planet
M. Antoniadi's drawings are, undoubtedly, worthy of the
highest admiration.
It is useless to go again into a discussion on the advantages
of using large and small apertures. It is a matter which must
depend on practical experiment. Professor Lowell, after
many years' experience with a telescope of the finest make,
situated as M. Antoniadi admits in the finest atmospheric
conditions, appears to have found that his best results are not
obtained when he is using his full aperture of twenty-four
inches.
It may be interesting if I make a quotation which refers to
Professor Lowell's observations from a book entitled " Is Mars
habitable ?" by Professor Wallace, F.R.S., who is as much
opposed to the theory of the artificiality of the canals as is M.
Antoniadi. He writes on page 14 of this book, in reference to
one of Professor Lowell's works, " No one can read this book
without admiration for the extreme perseverance in long-
continued and successful observation the results of which are
here recorded, and I myself accept unreservedly the whole
series."
I believe that much of the dispute as to the existence or
non-existence of the canals as straight lines arises from a
confusion between acuteness of vision (or the perception and
separation of fine detail), and sensitiveness to impression (or
the perception of faint contrasts). The two qualities rarely
go together in a high degree though one is often erroneously
taken as a guarantee of the existence of the other.
J. E. MAXWELL.
84, Dartmouth Road, N.W,
REVIEWS.
CHEMISTRY.
Laboratory Text Book of Chemistry. — By V. S. Bryant,
M.A. Parti. 246 pages. 10-in.X 72-in.
(J. & A. Churchill. Price 4/- net.)
The method upon which this text book is based is excellent,
for it aims at suggesting the use of experiment at every stage
of its course. From the very first the student is encouraged
to test facts and statements for himself, and the danger of his
learning the theoretical part of the science by memory is
guarded against by the use of supplementary questions, the
answers to which will require thought. The present part
includes the fundamental principles of chemistry, and the
elements, ogygen, hydrogen, and nitrogen, and their chief
compounds ; and a further section is promised dealing in the
same thorough manner with valency, oxides, carbon, and
sulphur. Diagrams are provided where necessary, and blank
spaces and pages are left for pencilled notes by the teacher or
student C. A. M.
General Index to " The Chemical News." — Vols. I-C.
712 pages. lOi-in.X 7j-in.
(The Chemical News Office. Price 40/-.)
Not only subscribers to The Chemical News, but others
who wish to consult its pages, and others again who may
now be tempted to seek for information, will appreciate the
issue of a general index to Volumes I to C of the periodical in
question, which appeared between the years 1860 and 1909.
The amount of labour entailed must have been very great.
The detail which has been gone into is shown by the fact that
subjects and authors are both given, while many of the former
are subdivided, and cross-references have been introduced.
Although the index contains two thousand one hundred and
thirty-six columns, the book is of a convenient size and is only
an inch and five-eighths thick. All chemists should show
their appreciation of the enterprise of The Chemical News
W. M. W.
by adding this valuable index to their library.
ENGINEERING.
Continuous Beams in Reinforced Concrete. — By Barnard
Geen, A.M.I.C.E., M.S.E., M.C.I. 210 pages. 14 illus-
trations. lli-in.X8$-in.
(Chapman & Hall. Price 9/- net.)
Continuity in reinforced concrete structures is at the same
time one of the most advantageous features possessed by the
material and one of the difficulties that has to be dealt with
by the designer. In steel structures continuity of beams can
to a great extent be avoided. In reinforced concrete the
monolithic nature of the structure makes such an easy
solution of the problem impossible. Considerable experi-
mental work has been done on the question of continuity of
structures by the French Government Commission and other
bodies, but hitherto the literature of the subject has lacked
a simple and reliable guide to the stresses to be expected in
continuous beams.
Mr. Geen has isolated the question of their determination,
and has worked out the bending moment and shear diagrams
for two, three, and five spans under five different forms of
loading. These diagrams have been combined, so as to give
directly the maxima positive and negative shears and bending
moments to be provided for in the cases dealt with.
In addition, such closely allied questions as the haunching
of beams, the bending stresses in columns due to the
continuity of the beams, the effect of subsidence of the
supports, and some features of tests of structures are also
briefly dealt with by the author.
The book is a useful contribution towards filling a decided
blank in the literature of reinforced concrete. The author
wisely stops at the determination of the stresses, and does not
proceed to discuss the method of determining the sections
necessary to resist them. That has been dealt with ad
nauseam in the literature of the subject.
The scheme of the work is unconventional. Out of a total
of two hundred and ten pages only some thirty-seven are
occupied by explanatory letterpress, the remainder being
devoted to diagrams and tables. The omission of the usual
padding and the general clearness and conciseness of the
letterpress enhance the value of the work and increase its
usefulness as a reference work for practical men.
N. M.
MICROSCOPY.
The Microtomist's Vade-Mecum. — By Arthur Bolles
Lee. 7th edition. 526 pages. 9-in. X5j-in.
(J. & A. Churchill. Price 15/- net.)
Since the first appearance of this book in 1885 no fewer than
seven editions have been called for, and no better testimony
to its value as a work of reference could be wanted. It is
one which every microscopist who does any real work, as
well as every biologist who makes researches, must consult
again and again. That it has been once more brought up to
date is matter for congratulation, and that the new edition
should be in the hands of everyone interested is shown by the
fact that the index alone gives more than seven hundred new
entries.
W. M.W.
.ZOOLOGY.
Notes on the Natural History of Common British
Animals and some of their Foreign Relations. Verte-
brates.—By Kate M. Hall, F.L.S., F.Z.S. 289 pages.
64 illustrations. 7i-in. X5-in.
(Adlard & Son. Price 3/6 net.)
Miss Hall's object in writing this book is to give those who
are engaged in the busy routine of elementary teaching such
information as she thinks would be of great service to them
in interesting boys and girls in our common British animals.
We think that Miss Hall has most successfully fulfilled her
purpose. To get together anything like the amount of
material which is here brought into convenient compass, very
much reading would have to be done, and it is quite probable,
not to say practically certain, that those who lack the Author's
training and experience would overlook many of the very
interesting points which give the book its charm. It will
appeal strongly, not only to the teachers for whom it is meant,
but to all those whose tastes lead them to love natural
history. w. M. W.
NOTICES.
LIEBIG'S LABORATORY— A CORRECTION.—
Figure 395, which was labelled Liebig's Laboratory, is in
reality from a photograph of a Pharmaceutical Laboratory of
the eighteenth century, reproduced at the Historical Medical
Museum.
CHANGE OF ADDRESS.— Messrs. Wratten & Wain-
wright, Ltd., have removed from Croydon to Kodak House,
Kingsway, W.C. A new factory has been erected for them
at Wealdstone, which will enable them to enjoy all the
resources of the Kodak plant.
SECOND-HAND APPARATUS.— Mr. Charles Baker's
catalogue, No. 53 P, contains a classified list of second-hand
photographic apparatus. This is kept separate from other
second-hand instruments, of which catalogue No. 54 has just
been issued, containing more than two thousand items, all of
which are guaranteed to be in perfect working order.
ZOOLOGICAL BOOKS.— The most recent of Messrs.
John Wheldon & Company's catalogues contains nearly twelve
hundred entries dealing with the Invertebrata, exclusive of
Insects.
440
Knowledge.
With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News.
A Monthly Record of Science.
Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A.
DECEMBER, 1913.
STELLAR SPECTROSCOPY FOR BEGINNERS. II.
By PROFESSOR A. W. BICKERTON, A.R.S.M.
Sound and Light.
We speak to one another by means of the vibrations
of air ; the stars tell us their story by the move-
ments of a medium we call ether, which is perhaps
best conceived of as a highly elastic jelly. We
cannot see the air, but we can feel it, and when it
moves swiftly enough it may knock us down or
hurl us over a house. We can neither see nor feel
the ether, yet able men tell us we have more proof
of the existence of ether than of matter, while some
think matter is ether in motion. Air and other
matter are made up of little moving particles of
extreme minuteness called " atoms."
Atoms.
A popular way of putting the size of atoms is to
say that there are more atoms in a drop of water
than drops of water in the Atlantic Ocean.
Perhaps the best way of realising some of the
properties of atoms is by means of a little instrument
Sir William Crookes made and called the sphin-
thariscope. By means of this pretty toy one can
see the effect of swift atoms of helium hitting a
surface of sulphide of zinc, each blow producing a
flash of light. The point of a needle is coated with
a little radium and placed in front of the zinc
surface, which thus becomes luminous. Solid radium
is for ever breaking up into other elements and
becoming a heavy and a light gas, and it takes two
thousand years for radium to half become gas. In
thus changing, each heavy atom of radium loses a
light atom of helium and becomes the atom of
another heavy element called " niton," or " radium
emanation," which is a gas. The element helium is
extremely important in stellar spectroscopy, and we
require to know a lot about it ; at present we want
to form an idea of the minuteness of the atom.
The zinc surface, with the radium-coated needle in
front, is put at the back of a little brass box with a
small convex lens in front. This instrument is
called a spinthariscope or scintilliscope. On looking
through the lens in a perfectly dark room, each
individual atom of helium as it strikes the sensitive
surface makes a flash of light. One sees hundreds
of such flashes each second. In some spinthari-
scopes this has been going on for years, and will do
so for thousands of years more without much
apparent diminution of the number of escaping
atoms of helium. Heat or cold makes no apparent
difference in the speed of escape of the helium
atoms, and no physical or chemical treatment seems
either to hurry up or in any way change the rate at
which these atoms — the so-called " alpha particles '
— leave the radium. Such, then, is the minuteness
of the atom.
An atom, although so small, is of wondrous com-
plexity, but for purposes of spectrum analysis we
had best think of them as little spherical bells flying
about in all directions, ringing for a little time after
they hit one another, and, like bells, ringing true to
tone. Like other bells also they alter the character
of the note according as to how hard and how often
they are struck. Heat makes atoms move faster,
and so when a gas is heated the particles hit harder,
and more overtones are produced. There is a
wonderful complexity in these atomic overtones ; the
atom of iron gives off thousands ; some atoms seem
to be much less complex. Many atoms seem to be
like compound bells, as though made up of many
bells of different tones fixed together.
441
442
KNOWLEDGE.
December, 1913.
Helium appears to be a very complex atom ; in fact
it seems to be an inseparable double atom, each part
being groups of bells. In it, however, one
characteristic tone rings out so clearly that midst the
complexity we can recognise helium by a line of a
pure yellow tint.
Colour.
The vibrations of a sheep bell we call sound ;
those produced by the atoms we call colour ; so it is
by colour the stars tell us their story. In the
spectrum the pure tints of singing atoms stand
apart, each in its proper place and so form the
cipher messages that reveal the mystery of the
stellar heavens. These ciphers are being gradually
deciphered and read by our industrious observers.
But " when the mind is blind the eye does not
see." What are wanted are guiding hypotheses, and
on all sides workers are awakening to this need.
Now their want is felt, the keys to open the doors of
the mind to see the richness of the corridors of space
and the many mysteries of Creation will surely be
forthcoming.
Some of these cosmic keys were found a long time
ago, but have only just begun to be used ; yet already
they have opened up many rich realms of Nature.
Vibrations.
Sound and light are both examples of propagation
of vibrations by wave motions. One gains a good
idea of wave motion by watching a field of ripening
wheat when moved by the wind. The waves travel
the length of the field, yet one knows the individual
heads remain each on its own stalk ; each con-
stituent of the wave only oscillates. Ear after ear
moves in succession, and so the motion looks to be
one of translation.
If a stone be thrown into the middle of a still
lake, the disturbance starts a series of waves that
travel until they reach the margin of the water. Yet
although the waves travel outwards, a cork on the
troubled waters merely moves up and down.
The speed of the wave depends on the elasticity
and density of the medium ; elasticity increases and
density diminishes speed. Elasticity in the air is
perhaps best understood by resistance to compres-
sion. Make the air in a football hot, and it resists
compression more, and is more elastic. The reason
is that the particles of air fly faster. The velocity
of a sound wave in a gas depends on the speed of
the moving molecules of the gas. Thus, at the
same temperature, hydrogen particles move four
times as fast as oxygen particles. So sound travels
four times as fast in hydrogen as it does in oxygen.
A tuning fork strikes a gas particle as a bat does
a ball, and it bounces away a minute degree quicker
than it came. It hits its next particle more quickly
than normal, and so a wave is produced. Sound
waves are often many feet in length and travel one
thousand one hundred feet a second. Light waves
are many thousands to the inch, and travel one
hundred and eighty-six thousand miles a second.
A tuning fork may only move one hundredth of
an inch. Yet it produces waves of sound that travel
thousands of times as fast as its own motion, and
the speeds of these waves differ whether they be
transmitted by gas, liquid or solid ; for example, if
they travel in air, in water, or in glass.
The curious thing is that the wave travels fastest
of all in the densest of these three substances. Not,
however, because it is dense — density reduces the
speed of progression — but because it is more elastic;
it recovers from compression more energetically.
How are we to explain these phenomena? We may
do so as suggested by imagining the tuning fork to
be a bat, hitting swift molecular balls thrown by a
demon bowler. The bat causes the balls to bound
back quicker than they come. In the case of liquids
and solids potential energy of molecular and cohesive
attraction has been converted into molecular kinetic
energy, so the molecules oscillate quicker than in
gas. Molecular and cohesive attraction make the
liquid and solid more elastic.
Light.
A beam of common white light is one of the most
complex things in existence. The waves of sunlight
are of many lengths and move in many planes. In
this respect the motion of sunlight is more complex
than the motion of the air when stirred by an
orchestra.
The vibrating particles of air, as the waves come
from a musical instrument, move in the line of
propagation towards and away from us ; not so
light. In the ether waves the motion is across
the direction from which the light is coming. As
the waves enter the eye the motion may be
horizontal, or vertical, or in any plane. In common
light they move in all planes— in all azimuths, as
astronomers say. When they are sorted out so as to
move in a single plane we say the light is polarised.
An instrument called the polariscope is used to so
sort the waves of light. A sound wave cannot be
polarised ; its sides do not differ. In plane-polarised
common white light the ether moves in one plane
only, but its waves are of many lengths. It is the
work of the spectroscope to sort the waves into their
different lengths. Light consisting of such separate
waves moving in one plane is said to be pure mono-
chromatic polarised light. A ray of polarised light
of any pure tint is the simplest conception we can
have of any beam of light. We picture it best by
imagining a tightly stretched skein of silk being
jerked, and watching the waves travel along the
length of the silk. Let us imagine an atom of
sodium to be vibrating, and picture the successive
motions in the ether as moved by the yellow beam
of light after it has passed through a polariscope.
Some transparent crystals have a structure like a
gridiron with very close bars. These minerals only
allow the vibrations of light to pass in one plane.
Such a crystal is a polariscope ; there are many more
effective kinds of polariscopes, but the action of
these crystals is easy to imagine.
December, 1913.
KNOWLEDGE.
443
Polariscope phenomena are not often studied in
spectroscopy, and will not here be further developed.
Refraction of Light.
A wavy line is a fair representation of a
simple ray of light of a pure tint polarised in a
plane (see Figure 515). In this each particle has
moved on its upright line, and the wave has
advanced. A beam of common white light is
made up of myriads of such waves of different
lengths moving in different planes. It is the duty
of the spectroscope to sort and to spread these
mixed colours into a long strip in which the waves
of different lengths stand out distinctly in the order
of their speed or length. This sorting is effected by
Figure 515.
prisms or by a parallel set of very close, fine lines
ruled on metal or glass, and called a grating. We
will try to understand the action of a prism on a ray
of light. As long as a beam of light travels in a
W
Wf\TER.
Figure 516.
uniform medium, such as still air or still water, it
moves straight forward at a uniform speed. In
angle. If the ray be a pure tint it is bent as in
Figure 516. If the pure ray pass through a prism
of glass it is bent both on entering and leaving, as
in Figure 517.
Refrangibility of Light.
A white beam of light may be made up of two
pure complementary colours. The best colours to
Figure 518.
use are green and red. If such a white beam passes
through a prism the two colours are differently bent,
and so separated as in Figure 518.
The white beam of light from an " Osram " filament
lamp has a myriad of different wave-lengths. Those
the eye can see, range from about thirty- three
Figure 519.
thousand to sixty thousand to the inch. In this
case the prism separates them into a rainbow-tinted
streak with the red at one end and the violet at the
other, in the order shown in Figure 519. The red is
Figure 517.
n G E DB
Figure 520.
INFRft RED
passing from one medium to another a beam of least bent ; then in order come orange, yellow, green,
pure light alters speed, and if it falls obliquely on blue, indigo, and violet. All the colours shade into
the plane surface of separation it is bent at an one another and there are thousands of tints, each
444
KNOWLEDGE.
December, 1913.
of a different wave-length. In popular lectures, to
give an idea of what has happened, I use the simile
of a crowd.
Simile to Picture a Spectrum.
If a strong light shone on a crowd dressed in all
the colours of the rainbow, at a distance the crowd
would appear to be clothed in white.
Suppose the crowd of many thousands to be made
up of individuals of all heights, the tallest about
twice as high as the shortest. The tallest are
dressed in deep red, then as they are shorter the
tint gradually becomes crimson, then passes to
scarlet, to orange, to yellow. The individuals of
intermediate height are yellow-green, still shorter
blue-green, then follow all the tints of blue, of indigo
and violet down to the lavender-grey, which some eyes
can see and others cannot. Colour-blind men
might not be able to see the tall ones. Eyes differ
in their power to see the two ends of the spectrum.
All the crowd exactly keep up with one another.
The tall red fellows stalk along, and the
little weak violet ones run to keep up, the size
of the stride representing the wave - lengths of
various coloured light. Every individual proceeds
forward in an exactly straight line. Then they
come to the prism ; it is a strong turning impulse.
Imagine a blast of wind blowing at right angles to
the travelling crowd. It turns them all a bit, but
the little weak ones, the violet, are turned much
more than the strong red, and all the intermediate
tints are turned in proportion to their speed of step
or their shortness or weakness. All three ideas are
important. Then, after passing the impulse of the
prism, again they go straight forward. If the crowd
be a very narrow one it corresponds with a narrow
slit. At once it begins to sort itself into its
constituent colours. The crowd broadens as it
travels ; after a time instead of a mixed crowd its
front is a long orderly line of individuals, a rainbow-
tinted streak, a spectrum, with the short violet
waves running at one end, and the tall red stalking
along at the other end. Supposing the individuals
of a certain height were truants, there would be a
gap, as when the electric arc shines through a
sodium flame. Supposing there be many truants of
different wave-lengths then there will be many gaps,
and we get the analogy of the solar spectrum.
Heat and Chemical Action.
White solar light is even more complex than the
coloured crowd : there are taller fellows than the
longest red and shorter than the shortest violet ;
they are in invisible grey, and the eye cannot see
them. The long waves are strong and the short
waves tricky. The big slow waves act as robber
brigands ; they can knock a whole molecule and
start it flying. The little waves are weak thieves
that cannot deal with a whole molecule, but can
steal his atoms.
The invisible ultra-violet waves are better pick-
pockets than the strong invisible infra-red. In the
solar spectrum the greatest energy is in the heat-
waves at and beyond the red end. The chemical or
actinic power of the spectrum is near and beyond
the violet end. The long waves are heating because
they move the whole molecules ; the short waves
are photographic because photography depends on
loosening and breaking up the molecule. The chloride
of silver is pulled to pieces and the silver deposited
by the quick vibrations of light that are not power-
ful enough to do much in the way of moving the
whole molecule and so heating the compound. The
height of the parts of the three curved lines in
Figure 520 gives the value in the entire solar spectrum
of its three properties ; that is, its energy or heat,
its light as it affects the eyes, and its actinism or
power to pull molecules to pieces. The power to
pull to pieces is also feeble energy, so energy is in
all parts of the spectrum ; but generally the higher
the temperature the greater is the ratio of light to
heat and the actinic power to the total energy.
Generally, also, the higher the temperature, the
greater the number and complexity of overtones the
atoms produce as they strike one another. Heat
being molecular indiscriminate motion, the velocity
of molecules increases with the temperature.
If a platinum wire be heated by an electric
current and used instead of a slit, and looked
at with a prism fixed over a hole in a large card with
the parallel edges of the prism held parallel to the
platinum wire, a good spectrum of the hot wire will
be seen. Of course, one does not look directly
towards the wire, but in the direction the rays are
bent by the prism. When the current is such that
the wire is just visible a red mass of light is seen.
As the resistance is lessened and the current
increases, the wire brightens, and as it does so the
red glow spreads to orange, then yellow is added,
and other successive colours of the rainbow show
themselves. When the platinum is near its fusing
point, a magnificently perfect spectrum of great
purity is produced. Thus we see the effect of
increased temperature in extending the spectrum
towards the violet ; that is, in increasing the speed of
movement of the molecules and consequently lessen-
ing the wave-lengths. This is the effect when we heat
a solid ; because its molecules cannot move freely,
it is like a mass of touching bells from which by
shaking we can only get a jangle of noise and no
music. The tightly fixed atoms of a solid have no
room for free motion, so they can only jangle and
give waves of every kind.
When a bell rings alone it gives a musical note,
and when a vibrating atom is free in a rare gas it
gives colours ; often of many very pure tints.
The colours in the spectrum of a star tell us its
story. The instrument we read the cipher message
with is the spectroscope, and the tale it tells us
depends on our understanding the laws of light and
widely correlated sciences.
(To be continued.)
December, 1913.
KNOWLEDGE.
445
From a photograph by J H. Worthington.
Figure 521. Flash spectrum obtained near Ovar, Portugal, 1912, April 17th, during a total solar eclipse, with a prismatic
camera consisting of a 2-1 inch Achromatic Quartz and Rock-salt lens of 50 inches focus with two 50° Quartz prisms in
front of it. Exposure, about ^-second. The photograph from which this is taken is unique.
(See " Knowledge," November, 1913, page 408.)
Figure 522. An enlargement of a portion of the flash spectrum shown in Figure 521.
From spectrograms taken with a 2-prism flint spectroscope by F. H. Hills, Fulgaon, India, January 22nd, iSqS.
Figure 523. A'' and Bf, spectra showing the flame bands of the reversing layer of the Sun seen during an eclipse.
Compare the definition and straightness of the lines in these spectra, photographed through a slit, with the circles in
Figures 521 and 522.
* At point of second contact, t At point of third contact.
44 6
KNOWLEDGE.
December, 1913.
Figure 524. Gannets in the Southern Hemisphere: Sulti capensis on Bird Island.
FIGURE 525. British Gannets: Stlla bassana on the Skellij;. Ireland.
(From "The Ganuet," by J. H.GGurney, by the courtesy of Messrs. YYitherby & Co.)
REVIEWS.
AVIATION.
Aviation. — By Algernon E. Berriman (late Technical
Editor of Flight). 360 pages. 32 illustrations. 6j-in.X 5j-in.
(Methuen & Co. Price 10/6 net.)
Mr. Berriman has attempted a Herculean task. He has
not only endeavoured to cover the entire ground of a
tremendous subject, but he has aimed at producing a book
that shall appeal to the whole range of possible readers — from
the tyro whose knowledge of flight is limited to a single visit to
an aerodrome, to the experienced aviator desirous of under-
standing the rationale of his movements in the air, or the
aeroplane constructor aiming at the perfect machine.
In a measure the author has accomplished the feat. In
one sentence he explains that an aeroplane does not flap its
wings ; in another he becomes severely technical over the
differential negative warp. Some really admirable simple
examples and experiments, that the schoolboy will delight
in, are followed by formulae of Pressure and Resistance
Constants. This is well enough, but the reader of the
entire volume is left wondering whether the attempt has
really been worth while, or whether the schoolboy and the
aviator may not both be slightly disappointed.
The only conceivable way in which such a task could be
accomplished is in a series of separate articles, and it is
of this that the volume with its twenty-four appendices really
consists. But the arrangement of these chapters might
well have been improved upon. The chronology is inten-
tionally turned upside down, but the result is a loss of
sequence and coherence. Many things come over twice ; nor
does the choice of subjects always seem wise. A description
of the various makes of aeroplanes would have been more
interesting than the Official Report of the Military Trials
of 1912.
Nevertheless the book is inspiring and one to delve into ;
for it is full of good things. The debt that aviation owes to
Sir George Cayley is acknowledged more fully than ever
before, and it is pointed out how aeroplane gliders might have
been in use centuries before any sort of engine was known.
" If the brave spirits of those times had sought to emulate the
soaring feats of birds, there is very little doubt but that a man at
the present day would be as much at home in the air as he is,
for example, in the water."
It may be questioned, by the way, if Mr. Berriman's
description of the sensation of flying is the general experi-
ence. It is not the writer's, at any rate.
If this book is not wholly satisfying, it is at least brimful
of information and interest. It is extremely well illustrated
and produced.
G. B.
CHEMISTRY.
Rubber and Rubber Planting. — By R. H. Lock, D.Sc.
245 pages. 32 illustrations. 7i-in. X4|-in.
(The Cambridge University Press. Price 5/- net.)
So many industries are now dependent upon a plentiful
supply of rubber that a book which describes in a simple
manner the nature of indiarubber and the science and practice
of planting the trees, should meet with a wide welcome. The
authoritative account given by Dr. Lock is not only extremely
interesting to read, but should also be of real value to the
prospective rubber planter and to those who wish to interpret
the prospectus of a rubber company.
Separate chapters are devoted to the physiology of the
latex, planting and harvesting operations, and the pests and
diseases to which the plant is liable. The book does not
profess to deal exhaustively with the chemistry of the subject,
but an outline is given at sufficient length for a non-chemical
reader, while there is a clear summary of the different pro-
cesses used in the manufacture of rubber goods.
The description of the industry gains much by the illustra-
tions, which include ten full-page photographs of methods of
tapping the rubber, diseased trees, apparatus, and so on,
and excellent line drawings, specially made by Mr. Denton
Sayers, of the different species of rubber-producing plants.
C. A. M.
Osmotic Pressure.— By A. Findlay, D.Sc, F.I.C.
84 pages. 2 illustrations. 9-in.X6-in.
(Longmans. Green & Co. Price 2/6 net.)
The latest addition to the Monographs on Inorganic and
Physical Chemistry is written by the general editor of the
series, and deals with the subject of osmosis upon similar lines
to those followed in the preceding monographs. Readers of
" Knowledge " will recall the wonderful osmotic forms
described by M. Leduc, and his remarkable theories as to the
part played by osmotic processes in the development of life.
It is another of the points of contact between physics,
chemistry, and biology, and biologists in particular will
welcome the appearance of a book which can be used as a
laboratory companion. The subject is not intended to be
exhaustively discussed, for the aim of the monographs in this
series is to summarise the present condition of knowledge in
each branch and to bring together the results of investigations
which are widely scattered in scientific publications all over
the world. References to the original papers and a full index
increase the value of the book to the practical worker, while
the general student of chemistry will here find an excellent
outline of this branch of physical chemistry.
C. A. M.
Organic Chemistry for Advanced Students. — By J. B.
Cohen, Ph.D., B.Sc, F.R.S. 427 pages. 8|-in.X5i-in.
(Edward Arnold. Price 16/- net.)
In this work Professor Cohen amplifies and extends the
course of lectures which he published six years ago, so as to
give, not only a general historical survey of the rise of organic
chemistry, but also an account of the recent researches
showing the connection between physical properties and
chemical structure.
Although full references are given at the foot of each page
to the original publications quoted in the text, the book is
intended rather to guide the student in the direction he may
profitably explore than to serve as a reference handbook.
Starting with an outline of the history down to Kekule's
theory, the author proceeds to discuss the valency of carbon,
and summarises the facts which tend to prove that, contrary
to the belief which was long regarded as almost an axiom,
carbon need not necessarily be tetravalent, but may be
tervalent or bivalent.
In the following chapters full outlines are given of the
nature of organic reactions, of their dynamics, of the relation-
ship between physical properties and structure, and of colour
and structure, and the book concludes with a good index of
authors and a subject index. The various theories, which are
not infrequently in conflict, are discussed at sufficient length,
the arguments for and against them being fairly presented.
It is difficult to overrate the value of this book to the
student. Organic chemistry was for far too long a time
merely a storehouse of an immense accumulation of facts
which were apparently uncorrelated. The aim of each
investigator was to prepare a new crystalline compound, and
so add another substance to the long list. But now the order
underlying all these disconnected facts is gradually being
unfolded, and this book of Professor Cohen will help all who
seek its aid to grasp the new conceptions which are modifying
the whole course of organic chemistry.
C. A. M.
447
448
KNOWLEDGE.
December, 1913.
GEOGRAPHY.
Japan's Inheritance (the Country, its People, and their
Destiny).— By E. Bruce Mitford, F.R.G.S. 384 pages.
12 maps and plans, and 75 illustrations from photographs.
9-in.X6-in.
(T. Fisher Unwin. Price 10/6.)
More than half the book describes the physical inheritance
of Japan, mainly from a geological point-of-view, laying
special emphasis on volcanic phenomena ; here, as in all parts
of the work, the author describes many personal experiences
which give the reader a vivid impression of local conditions.
Excellent photographs illustrate his descriptions ; one longs
for a better physical map. He adds a sober account of the
present-day state of affairs in the country, warning us that
the West and the East have only half learnt each other's
lessons, so that there is danger ahead : America has not learnt
to treat Orientals with due respect, and Japan, inevitably to
be linked with China, has acquired no spiritual foundation
to counterbalance its new materialism. Japan has a definite
mission to the East, which can only be fulfilled satisfactorily
if these defects are remedied. The book is well worth
reading. JCC
The Continent of Europe. — By Lionel W. Lyde, Professor
of Economic Geography in University College, London.
446 pages. Physical maps of each country, and many
diagrams. 9-in. X6-in.
(Macmillan & Co. Price 7/6 net.)
In a closely- written book of over four hundred pages,
Professor Lyde gives us a very interesting study of Man in
Europe, as influenced by geographical factors such as surface-
features and climate, based upon Europe's characteristic penin-
sular formation. For the sake of this study, he is prepared to
accept the tetrahedral theory of the development of world-
forms as a convenient working hypothesis ; the surface-relief
is examined in relation to this and its effect on the move-
ments and habits of Man. His intimate knowledge of
economic conditions and their correlation with the various
physical controls renders the book worthy of careful study ;
he makes one realise that in the long run geographical
conditions must play the fundamental part in shaping
the characters and destinies of countries and their
inhabitants. In Europe, especially, human history and
sentiment count for so much that he rightly groups his
matter around political units rather than " natural regions,"
and he shows great scientific ingenuity in tracing geographical
influences in history. It is a most inspiring book.
J. C. C.
OCEANOGRAPHY.
The Ocean. — By Sir John Murray, K.C.B., F.R.S.
256 pages. 12 plates. 6j-in.X4i-in.
(Williams & Norgate. Price 1/- net.)
It is not easy to do justice to this excellent manual of
Oceanography in a short review. From his great knowledge
of the subject Sir John Murray has condensed into two
hundred and forty-three post octavo pages a very extensive
account of the Ocean from almost all points of view. In fact
the book is so full of the latest facts and contains so little
"padding" that it will serve almost as a textbook or work of
reference for Fachleute, as well as a manual for the interested
amateur. After detailing the methods of research, Sir John
Murray passes on to the depth, salinity, and temperature of the
Ocean. The difficult problems of " why the sea is salt " and
why the percentage of carbonate of lime is so small in the
waters of the ocean are explained, though perhaps hardly so
fully as might be wished by the unlearned. We have not
found reference to the recent suggestion that the sea contains
much decomposing organic matter which may be made use of
by many organisms hitherto believed to live entirely by the
holozoic method of nutrition.
Tides and tidal waves are next touched upon, followed by
an account of the difficult question of ocean circulation, the
interesting condition of the Black Sea being sufficiently
explained in the limited space at the author's disposal, though
we think the Gulf Stream hardly receives sufficient attention.
Plant and animal life are next dealt with, and the first part of
Chapter VIII is perhaps the most interesting and stimulating
portion of the book ; the latter half is mostly a catalogue.
The plates of marine organisms at the end of the book
are rather too sketchy to be of much value. We
note that Figure 16, Plate VIII is upside down. The
nature of the marine deposits is very ably described and the
author gives in this connection sundry cogent reasons for dis-
belief in " Atlantis " and " Gondwanaland." Finally the
structure and interrelation of the various geospheres are
discussed in a highly interesting manner. We can confidently
recommend the book to all those — -and they must number not
a few — who would learn, from one who is facile princeps
among living experts, something of the " wonders of the Great
Deep."
M. D. H.
ORNITHOLOGY.
The Gannet. — By J. H. Gurney, F.Z.S. 567 pages.
131 illustrations. 9-in. X6-in.
(Witherby & Co. Price 27/6 net).
A striking testimony to the interest which is now being
taken in British birds is Mr. J. H. Gurney's book on "The
Gannet," for he devotes no less than five hundred and sixty
pages to his subject. His sub-title is " A Bird with a
History," and no one after reading his latest contribution to
ornithology can deny that the Solan Goose has a long and
interesting story. There was, some years ago, a fear that
the Gannet might die out. We are glad to think with Mr.
Gurney that its numbers are increasing, and that its fish-
eating propensities are overlooked, while the traffic in its
feathers is ended and the name Solan Goose is quite forgotten
in the " trade." It is to the description of the bird's habits
that many no doubt will turn. The fact that the birds show
a considerable amount of affection for one another and indulge
in caresses after the period of courtship is over, is of interest,
as well as the curious way in which the birds gape from time
to time, and the number of accidents which are responsible for
their deaths. It might be deduced from the facts that the
Gannet only lays one egg and takes three years to come
to maturity that it is long lived, and a marked bird is said to
have reached the age of eighty years. Mr. Gurney's book is
really most exhaustive and fascinating, and goes into every
kind of detail. On page 446 we are permitted to give two out
of the many well-chosen illustrations.
PHYSICS.
Researches in Magneto-Optics. — By P. Zeeman, Professor
of Experimental Physics in the University of Amsterdam.
219 pages. 74 figures. 9-in. X6-in.
(Macmillan & Co. Price 6/-.)
The discoverer of the well-known " Zeeman effect "
dedicates his monograph to the memory of Michael Faraday.
The book itself is not unworthy of such an association. In
clearness and completeness of exposition, in true scientific
enthusiasm, and in generous recognition of the work done by
others, it is a fit successor of the " Experimental Researches."
To criticise such a book in a brief notice would be an
impertinence, and to deal with it adequately would require
more knowledge than the writer of these few lines possesses.
He is capable, however, of appreciating the clearness with
which the distinction between dispersion and resolving power
of a spectroscope is made in the opening chapter. The book
is an expansion of Professor Zeeman's lecture given at the
Royal Institution in 1906, and has been written specially for
Macmillan's series of science monographs. The translation
of the Dutch manuscript seems to have been admirably done
by Miss J. D.Van der Waals. The last twenty-five pages are
filled with the bibliography of the subject. Evidently the
book is one which every student of Physics should possess.
W. D. E.
STELLAR PHOTOGRAPHY FOR AMATEURS.
By W. H. STEAVENSON, F.R.A.S.
Considering the large and important part now
played in astronomy by the photographic plate,
it is strange that comparatively few amateurs are
actively interested in this branch of the science.
No doubt most users of telescopes have tried their
hand at photography at some time or another, but
such attempts are too often limited to the taking of
a few snapshots of the sun or moon in the principal
focus of the instrument, which is then applied once
more to some line of visual work with results that
are generally of questionable value. Without
wishing for one moment to discourage useful
visual work, it is the aim of the writer to show
the great possibilities of stellar photography from
the point of view of the amateur and to suggest a
few branches of astronomical work to which he may
profitably apply it.
A few words on the subject of equipment may not
be out of place. A common mistake on the part of
beginners is to attempt work on too large a scale,
using the biggest apertures and longest foci at their
command. After what .has been done by Roberts,
Keeler, and Ritchey, however, it is doubtful whether
many amateurs could make any useful advance in the
photography of individual clusters and nebulae. It
is in small-scale and wide-field work that the average
amateur will find it most profitable to engage. The
exact size and make of the lenses used must, of
course, be largely a matter of individual choice ; but
whatever choice is made there are at least two qualities
which a lens to be used for stellar work should
possess, namely, great rapidity and great covering
power. Slow lenses may, of course, be used, but
the necessary exposures will be so long that it will be
hardly worth while to use a lens whose aperture is
less than /5 or /6. Unless expense is no object it is
perhaps best not to try to combine extreme rapidity
and good covering power in one and the same lens.
It is much better, if possible, to have two lenses — a
portrait lens for rapid work on small areas and an
anastigmat for large fields. The portrait lens should
have a working aperture of /3 or /4, and should be
of at least twelve inches focus. Such lenses are
often to be picked up quite cheaply in second-hand
shops. Their covering power is rather poor, and if
the focus is not above twelve inches or so there is
no point in using anything larger than a quarter-
plate with them. As a rule their limit of fair
definition does not extend beyond a circle eight or
ten degrees in diameter. The anastigmat should be
of about eight inches focus, should work at /4 • 5 or
/4-8, and should cover a half-plate sharply at its
full aperture. Under such conditions the lens will
cover an"area in the sky of thirty by forty degrees,
or considerably more than four times the area
enclosed by the four chief stars of Orion. The
portrait-lens and the anastigmat may be used simul-
taneously, thus acting as mutual checks on each
other's work. If they are used separately, the
former will obviously be employed for detailed work
on small areas, while the latter will be used when it
is necessary for any purposes to cover a large region
of the sky at once. Of course, for all photographic
work necessitating long exposures an equatorial
stand is absolutely essential ; but it may be a very
simple one, and need not even be provided with a
clock. The latter adjunct is an obvious advantage
as a saver of labour, but, given the requisite patience
on the part of the operator, excellent results may
easily be obtained with hand driving alone. Unless
the telescope is a large one it is best to attach the
cameras as counterpoises to the instrument, as this
saves unnecessary weight, which is apt to militate
against smooth and easy driving. For guiding, the
out-of-focus image of a star, bisected by cross-wires
in the eyepiece of the telescope, should be used.
In order to correct for refraction, a slow motion in
declination is essential. Care should be taken to
follow accurately to within a few seconds of arc, as
even small errors are much more noticeable on
photographs than might be expected.
It now only remains to indicate in a general way
some of the uses to which such lenses as those
mentioned above may be put. First there is the
search for variables and novae. In this branch of
work it is best not to try to cover too much ground
at once, but to work systematically on one small
region at a time, preferably with the portrait-lens.
A small part of the sky, in or near the Milky Way,
should be selected and photographed repeatedly
with the same instrument at intervals of a few
days, the plates being carefully compared by super-
position or some other method. For the detection
of short-period variables it is best to make several
exposures of equal length and at equal intervals on
the same night, moving the camera slightly for each
exposure. The result will be a number of images of
each star, which will be of equal intensity in every
case, unless there is in the region a variable under-
going rapid change at the time, in which case it can
at once be detected by the inequality of its various
images. This method has been used with good
results by Professor E. C. Pickering at Harvard.
Another use for the photographic lens is in the
search for comets. For this the anastigmat, on
account of the large field it covers, is especially
suitable. A region of the sky not too far from the
449
450
KNOWLEDGE.
December, 1913.
sun should be chosen, and the photograph taken as
near to the time of sunset or sunrise as the length
of the twilight will permit. The writer would par-
ticularly recommend this branch of work to
observers living in or near the tropics, where the
twilight is of short duration. For the actual study
of the changes in comets' tails the portrait-lens, on
account of its rapidity, is more suitable than the
anastigmat, though both may be used.
The visual study of the paths and radiants of
meteors may very profitably be supplemented by
work with the camera. Owing to the rapidity of
their flight, only the brighter meteors will record
themselves, but a few definite lines on a measurable
plate will be of more value in determining the
position of a radiant than any number of loose
statements based merely on eye-estimations.
Though not strictly speaking " stellar " in character,
comets and meteors have been included in this
article as being objects which are photographed
under essentially the same conditions as the stars
themselves.
There are many other ways in which photography
can help the amateur astronomer. Its value as a
means of map-making is considerable. It is often
desirable, for the identification of faint satellites and
for other purposes, to have an accurate map of some
region which shall show all stars down to a fairly
low magnitude. To those who cannot afford to
buy the Franklin-Adams charts or the Astrographic
Atlas, a home-made map, made in an hour or two
with a portrait-lens, will often be very useful.
THE ALCHEMICAL SOCIETY.
At a meeting of the Alchemical Society held Friday
evening, November 14th, a paper was read by Madame
Isabelle de Steiger, entitled " The Hermetic
Mystery," the chair being occupied by the acting
president, Mr. H. Stanley Redgrave, B.Sc, F.C.S.
Madame Isabelle de Steiger's interpretation of the
theories and aims of the ancient and mediaeval
alchemists differs radically from that accepted by
many students of the history of philosophy and
science, her views in the main agreeing with those
expressed in that well-known but exceedingly rare
work, " A Suggestive Enquiry into the Hermetic
Mystery and Alchemy."
According to the lecturer, the doctrines under-
lying Alchemy were the primitive doctrines at the
heart of every ancient religion. Alchemy, she
maintained, was not concerned with metals but with
man, whom the alchemists endeavoured spiritually
to perfect through a process analogous to that said
to have been discovered by Mesmer. The Alchemists,
she said, formed a sort of free secret order, and their
writings were cryptogrammatic, being intended to be
understood by one another only. They were couched
in the language of chemistry to mislead the ignorant,
on account of the danger attendant upon any
misuse of the processes with which they dealt.
The full text of the lecture has been published in
the November number of the Society's Journal.
THE EXHIBITION OF THE NATURE PHOTOGRAPHIC SOCIETY.
Some three years ago, through the initiative of Mr.
Carl Edwards, of Leeds, the Nature Photographic
Society came into existence, That there was a place
for it soon became evident. A large majority of the
leading nature photographers including Messrs.
Edward J. Bedford, Richard Kearton, F. Martin
Duncan, Oliver G. Pike, and John J. Ward, joined
the ranks of the members, and the organisation
became a distinct success, while a quarterly journal
entitled The Nature Photographer, has since
appeared regularly. If in the olden times all roads
led to Rome, nowadays most things find their way
to London, and last year the Annual Meeting of the
Nature Photographic Society took place in the metro-
polis, and what is more, the first exhibition of
photographs by members of the Society was held
during the months of October and November by the
courtesy of the Royal Photographic Society of Great
Britain at its house in Russell Square. It may be
said at once that an excellent series of pictures was
brought together and that Mr. H. Armytage Sanders,
who acted as organising secretary of the exhibition,
was able to fill all the space which had been kindly
placed at his disposal. As the movement in favour
of nature photography arose out of the interest which
was first of all taken in the hunting of British birds
with the camera instead of the gun, it was to be ex-
pected that photographs of birds would be well repre-
sented. Of them we ought to mention particularly
the gannet landing at the nest taken by Mr. Charles
Kirk with a "Birdland" Camera, the adjutant bird
in two studies of expression by Mr. Edward J. Jacob,
who sent also a very beautiful picture of a swan.
Many of the movements which are caught by
the camera look quite unnatural and are far from
being like drawings, so that those who say that
nature photographs should always be what is called
artistic do not understand their value and are talk-
ing rank nonsense. Such past masters in the art of
bird photography as Mr. Bedford, Mr. Kearton, Mr.
Pike and Mr. Sanders, were also represented, and we
are glad to see that Miss Grace Kearton is following
in her father's footsteps. Fungi and flowers were
fairly well represented ; the reproductions of Mr.
Essenhigh Corke's colour-photographs were very
striking. The president, Mr. Henry Irving, the
secretary, Mr. Carl Edwards, as well as Mr.
Somerville Hastings, sent pictures of fungi. Mr.
Hugh Main illustrated the life-histories of insects
and the habits of millipedes : his photographs of
the musk beetle we are able to reproduce on
page 451.
December, 1913.
KNOWLEDGE.
451
Figure 526.
Larva in stem. Natural size.
Figure 529.
Larva, lateral view X 2.
Figure 530.
Larva, ventral view X 2.
Figure 527.
Pupa, dorsal view X 2.
From photographs by
Figure 528.
Pupa, ventral view X 2.
Figure 531.
Imago X 2.
Hi/ok Main.
The larvae are to be found in the stouter twigs of the wiilow and are nearly full grown in March or April ;
they pupate in May, and the beetles emerge in August.
THE MUSK BEETLE (AROMIA MOSCHATA L1NNE.)
452
KNOWLEDGE.
December, 1913.
Figure 532.
a. b and c. Early stages of growth when the fungus is still yellow.
d. The fungus filled with a colourless liquid.
e. The partial formation of the sporangium.
f. A mature specimen studded with beads of moisture.
The portion below the dotted line is usually hidden below the surface of
the soil.
Figure 533.
The collapse of the
tissues after the ex-
plosion.
Figure 534.
g. Sporangium, highly mag-
nified, with a number of
spores still adhering to the
inner surface.
h. A single spore magnified
about S00 diameters.
Stages in the life history of Pilobnlits cry stall i it us.
(See page 453.)
., my.
ft /US'
Figure 535.
Dendromonas virgaria W'eisse (after Kent).
a. An isolated monad, highly magnified.
b. A colony of two monads in process of longitudinal division.
(See page 466.)
Figure 536.
The partial eclipse of the Sun, 1913, September 29th.
From a photograph taken with a telephoto lens at the
Union Observatory, Johannesburg, South Africa, by Mrs.
H. E. Wood.
(See page 459.)
AN EXPLOSIVE FUNGUS.
By P. J. ALEXANDER.
Among the various kinds of British fungi none, to
my mind, are more interesting than those which,
when mature, explode like a gun, shooting their
spores several feet into the air. Some of these
" ball-throwing " fungi belong to the Mucoraceae, a
family of the true moulds (Phycomycetae).
The easiest type of this class to find, and the one
that presents the greatest facilities for study (as
most of its movements can be watched with the
naked eye), is Pilobolus crystallinus. It may be
found in spring, summer, and autumn growing in
close clusters on all mammal dung, and especially
on that of horses, cows, pigs, and sheep. I have like-
wise met with it on the droppings of birds. It first
came to my notice quite by accident. One day, in
my country rambles, I observed some small red
pezizas on the sweepings from a sheep pen, and I
took some home with me in a tin box that I always
carry with me on such occasions. The next
morning on going to examine my find I was
astounded and delighted to see dense numbers of
crystalline bulbs surmounted by a black cap and
interspersed with tubes of a beautiful golden colour.
I kept the medium on which they were growing
moist, and examined the development of this new
fungus for ten consecutive days, and I think the
results of my observations and study may prove
interesting to readers of " Knowledge."
History. — This fungus was apparently unknown a
hundred and fifty years ago — at least we find no
mention of it in any literature prior to that date.
Scopoli was the first to call attention to it under
the synonym of Mucor obliquus in 1772 ; but it was
Wiggers who first enabled botanists to recognise
this fungus by his description of it published in
1780. It is a curious fact that Tode, whose name is
usually connected with this species, did not study it
till four years later. We come across it, it is true,
in a French work by Leveille and Durieu de
Maisonneuve in 1826; but they did little to
elucidate a knowledge of this fungus, as many
of their observations were erroneous. F. Cohn
noticed it in 1851, and Francis Currey further
investigated its formation in 1857. Two years
later a Belgian botanist and a native of Louvain
published his famous monograph on the subject,
showing that he had made a complete analysis
of this particular fungus, though still leaving one
or two questions unsolved.
Growth. — The first sign of this fungus on the
surface of the dung is a tiny golden speck, which,
however, soon becomes elongated and shoots up in a
golden finger-like tube. About three hours later
this tube swells out at the top into a small globe
(see Figure 532 a, b, c). Soon after this it loses its
colour, the tube and bulb become crystalline, and a
black hemispherical cap is formed on the top of the
bulb. This cap is the sporangium containing the
spores or reproductive bodies. At first it does not
seem very distinct from the rest of the bulb (see
Figure 532 e), but little by little a clear line of
demarcation becomes visible (see Figure 532 /).
The Pilobolus is now reaching maturity and ready
to discharge its spores. It is filled with a trans-
parent liquid which is slightly acid. Beads of
moisture often form along the stem and hang like
pearls around the bulb, giving the fully developed
fungus a most beautiful and delicate appearance (see
Figure 532 /). We can even observe with an
ordinary lens small worm-like animalcules moving
in the swollen bulb. It is now time to collect the
spore. The best way to do this is to hold a piece of
white paper a few inches over the black capsules.
If the light is good the tension soon becomes too
great and the caps are blown off with great force.
They are sometimes thrown to a height of three
feet. Before alighting on the paper they turn a
somersault in the air, so as not to strike the surface
with their convex side, but fall on the paper like an
inverted cup, shutting up the spores inside. This
black cap is made of a remarkably tough membrane
as we soon discovered in making a microscopic
preparation of the same (see Figure 534 g, which shows
this sporangium, about six hundred times enlarged, full
of yellow spores, ellipsoidal in shape). If the fungus
is not allowed sufficient light, or if the atmosphere
be too warm, instead of projecting the sporangium,
the whole fungus withers and topples over (see
Figure 533), and soon nothing is seen but a whitish
powder left by the dried-up skin of the stem.
The whole plant grows, develops, and dies within
twenty-four hours. If left out in the open in its
natural surroundings it attains maturity and explodes
shortly after sunrise ; but if kept in a room where
there is little or no sunlight the explosion does not
take place until midday or later, and sometimes not
at all. This would seem to show that not only
elasticity of the tissues but also light is a great factor
in causing the projection of the spores, which has
been variously attributed by different writers to
divers other causes, and erroneously to the tension
caused by the liquid in the stem. But if this were
the case, then heat would favour the explosion,
causing expansion ; but experience shows that it is
just the contrary which occurs.
The natural size of this little fungus is about
three millimetres ; hence it will be found rather tiring
to examine with the naked eye, but with a good
magnifying glass, giving eight or ten diameters, one
can study all its movements with ease and comfort.
One must be careful not to confound it with an
allied species, Pilobolus oedipus, which it closely
resembles, and which may be found in the mud and
slime of gutters ; but in this latter species the spores
are globular and of a larger diameter than those of
Pilobolus crystallinus.
453
THE DEITIES OF ANCIENT MAORILAND.
By R. W. REID,
New Zealand.
The perusal of books of travel, and of missionary
registers dealing with New Zealand about a hundred
years ago, provides the principal information the
world possesses concerning the old-time Maoris,
their habits and customs, and their religious beliefs.
No worthy effort seems to have been made to collate
the invaluable accounts of ancient Maoriland
scattered through the kind of works mentioned.
Here and there, in some old and faded missionary
register, scientific facts of the greatest interest and
importance are met with ; nor are they of less
moment because the writers did not always realise
their importance, or foresee the avidity with which
their somewhat artless contributions would be read
by succeeding generations. One has to skim
numerous heavy tomes — heavy in more senses than
one — to arrive at anything approaching clear con-
ceptions with respect to the religious beliefs— the
superstitions, some may designate them — of the
Maoris when they were first discovered by
Europeans.
The Maoris, like the Greeks, Romans, and other
races, had a great variety of gods. Atua was, how-
ever, their principal deity. Crozet, in his " Nouveau
Voyage a la Mer du Sud," mentions that the Maoris
with whom he came in contact had a number of
subordinate divinities to whom they were wont to
pray for victory over their enemies. A writer
(unnamed) in the Missionary Register for 1822 gives
a description of the Maoris' daily adoration of the
sun, moon, and stars. Of the heavenly host the
moon, he says, was their favourite. This statement
seems to be not fully borne out by the writer ; for he
observed that when addressing the moon the
Maoris employed a mournful song and appeared to
be as full of apprehension as of devotion. They
presented a totally different demeanour when
engaged in their adoration of the sun. Then their
arms were extended and partly uplifted, and though
their heads were bowed " there was an appearance
of much joy in their countenances." The songs
sung in their worship, or adoration, of the sun were
never solemn, as they were when the moon was
addressed, but bright and cheerful. The old Maoris,
in addition, held many strange ideas with regard to
some of the more conspicuous constellations. Not
only were the issues of human affairs influenced, but
also the future was indicated by the movements of
the stars. The Pleiads, shining in the deep blue of
the New Zealand sky, touched the imaginations of
the Maoris. Tennyson said the Pleiads
Glitter like a swarm of fire-flies tangled in a silver braid.
But the Maoris discerned there the presence of their
kinsmen. The Pleiads, according to Nicholas's
" Voyage to New Zealand," they believed to be
seven of their departed countrymen fixed in the
firmament. One eye only of each of those trans-
ported Maoris was visible, and in the form of a star.
But it was a common superstition among them — and
this fact is frequently mentioned in century-old
records — that after death the left eyes of chiefs
became stars.
The belief that the stars are the departed heroes
of the earth, as readers are aware, is old and wide-
spread. Traces of it can be found in the primitive
faiths of nearly every land. A shooting star was
regarded as an omen of ill, as generally a warning
of the approaching death of a chief ; and the
Maoris, like the rest of us, have their own man in
the moon. He, however, seems to be a kind of
deity. He is immortal, and possesses the power of
conferring immortality. He loved Rona, a Maori
maiden, and, as she loved him in return, she
accompanied him to the moon. Different versions
of Rona's life after her translation to the night
luminary are met with. One is that Rona remained
in the moon, and another that she returned to earth
to rejoin her Maori lover.
Atua, as stated, was the most powerful god in
ancient Maoriland. The word Atua is found in
several forms in most of the South Sea dialects, and
is thought by some to be allied with the Sanscrit
Dewa, the Greek Zeus, and the Latin Deus. This
god was deemed by the Maoris to be immortal,
omnipresent, invisible, and supreme. Yet, in spite
of those mighty attributes, he was believed to be, in
disposition, merely a vindictive and malignant demon.
The Missionary Register for 1823 mentions that
when a white clergyman spoke to the Maoris about
the infinite goodness of God they bluntly responded
with the query : " Are you joking with us ? " They
believed when anyone became sick, the illness
was caused by Atua, in the form of a lizard, having
gained admittance into the interior of the ailing
person, preying upon his, or her, entrails. Then
the tohungas, or priests, set to work. The Proceed-
ings of the Church Missionary Society for 1819
describes the old Maori mode of frightening, or
attempting to frighten, the demon god. The
tohungas, willingly assisted by the common people,
" addressed the most horrid imprecations and curses
to the invisible cannibal, in the hope of thereby
frightening him away." They imagined that, at
other times, Atua amused himself by entangling
454
December, 1913.
KNOWLEDGE.
455
the fishermen's nets and upsetting their canoes.
In the Missionary Register for 1823 is mentioned
a circumstance which helps to throw light on the
occasional ferocious attacks upon white explorers
and others made by the Maoris. Probably the most
notable, as it was among the first, of what appear to
have been either sudden acts of frenzy or of cold,
calculated massacre, was the slaughter of Captain
Marion du Fresne at the Bay of Islands in 1772.
Captain du Fresne, in command of the ship " Marquis
de Castres," and Lieutenant Crozet, commanding
the sloop " Mascarin," put into the Bay of
Islands to refit. Friendly relations were soon
established between the Frenchmen and the Maoris,
and for several weeks both races lived together in
harmony. " The inhabitants treated us with every
show of friendship for thirty-three days," records
Crozet in the volume already mentioned, " with the
intention of eating us on the thirty-fourth." Whether
the massacre was premeditated for a month or more,
or was suddenly resorted to in a fit of religious
excitement, has never been satisfactorily decided.
The fact, however, remains that the Maoris suddenly
attacked the party, killing, and afterwards eating,
twenty-nine of the number, including du Fresne.
Crozet had a narrow escape from the same fate,
but he eluded the savages and " lived to tell the
tale." The probability is that the murder of du
Fresne and his twenty-eight countrymen was due
to what in these later days would be designated
religious mania. The Register says : " The natives
have long suspected, ever since white men arrived
in their country, that their great god Atua has been
very angry with them for having allowed any white
men to obtain a footing in their country, a proof of
which they think they see in the greater mortality
that has recently prevailed among them."
The Missionary Register four years later is
found discussing these suspicions of the Maoris. It
was then apparent that they attributed their losses,
sickness, deaths — all their misfortunes — to the God
of the Christians. Him they denounced accordingly
as being cruel — at all events to others than
Christians. The article proceeds : " Sometimes
they more rationally assign as the cause of the
many deaths the diseases that have been introduced
among them by the whites. Until the whites came
to their country, they say, young people did not die,
but all lived to be so old as to be obliged to creep
on their hands and knees." Missionaries and
teachers tried to get the Maoris to believe that " the
white man's God " and Atua were one and the
same. The Rev. Samuel Marsden, New Zealand's
first missionary, in one of his letters relates a con-
versation he had upon this theme with some Maoris,
the sons of a chief, who had accompanied him to
New South Wales. When he told them that there
was but one God, they put the question : " Has the
pakeha's [white man's] God given the pakehas any
kumeras [sweet potatoes] ? " They failed to under-
stand why one God should give the Maoris kumeras
and the white man none ; and why, also, He should
be partial to the whites in the matter of cattle,
sheep, and horses and entirely neglect the Maoris so
far as these animals were concerned. But the final,
and to the Maoris the unanswerable, argument was :
" If one God made us both, He would not have
committed such a mistake as to give us different
colours — make one black, the other white." Mr.
Marsden, who, by the way, settled in New Zealand
in 1814, asked a Maori what he conceived the Atua
to be, and was answered : " The Atua is an immortal
shadow."
In " Nicholas's Voyage " appears, on the authority,
it is stated, of Nicholas's friend, Duaterra, a lengthy
and fairly precise account of the inferior deities of
the ancient Maoris. Their number was " very
great " and " each has his distinct powers and
functions." One minor god " was placed over the
elements, another over the fowls and fishes, and so
of the rest." Deifications of the different passions
and affections also found a place in Maori
mythology ; a fact which suggests a connection of
some kind with the early peoples of Europe and
Egypt. It is very remarkable, as Nicholas points
out, that the Maoris attributed the creation of man
to their three principal deities acting together, " thus
exhibiting in their barbarous theology something like
a shadow of the Christian Trinity." Still more
wonderful was their tradition respecting the creation
or formation of the first woman, who, they said, was
made of one of the man's ribs. Moreover, the
Maori's general term for bone is pronounced some-
thing like hevee, which certainly seems to be not
far removed from the Eve of Biblical narrative.
Chiefs of high standing had, according to Nicholas,
their own particular god or gods. When, for
instance, the ship " Active " was lying in the river
Thames, in the North Island, there was a gale of
wind, and this the natives on board attributed to the
anger of Hupa's god. Hupa was a chief who lived
near the Thames. An elderly native, a man of some
note apparently, Koro-Koro by name, informed the
master of the ship that, as soon as he got ashore,
he would endeavour to prevail upon the chief to
propitiate the offended deity. When Mr. Marsden,
trying to embarrass the Maoris of Kiapara, asked
them if they had ever seen or heard, or had any
communication with, the god of that locality — for
certain localities had their own particular god — he
was bravely informed that the god of the Kiapara
had been often heard whistling. Frequently chiefs
were called Atuas, or gods, even while they were
alive. There was, it will be observed, considerable
confusion as to Atua. Atua was the principal god ;
but the name was thus also applied to men not
thought to be specially endowed with supernatural
power apparently, but to those who considered them-
selves as the habitation of deities. An aged chief,
Terra by name, who is mentioned in the nineteenth
report of the Church Missionary Society, solemnly
assured a missionary that the god of thunder resided
456
KNOWLEDGE.
December. 1913.
in his forehead. Not to be eclipsed by this kind of
fame his neighbours, Shungie and Okeda, firmly
maintained, against all critics and sceptics, that in
them lived the gods of the sea.
The dwelling-place of the gods — they, like the
Maoris, lived largely in community, it would appear
— was always represented as being extremely
beautiful. " When the clouds are tinted with
bright and lively colours," writes Mr. Kendal, a
missionary, " the Atua above, it is supposed, is
planting sweet potatoes. At the season when
these are planted in the ground the planters
dress themselves in their best raiment, and say that,
as Atuas on earth, they are imitating the Atua in
heaven." Captain Cruise, in his journal, is
responsible for the statement that the Maoris he met
with a hundred years ago believed that the higher
orders among them were immortal, but that when
the common people died they perished for ever.
The spirit, they explained, left the body the third
day after death, till which time it hovered near the
corpse, hearing quite well all that was said to it.
But they held, further — and here again their beliefs
become somewhat complicated and contradictory —
that there was a separate immortality for each of
the eyes of the dead chief. The left ascended to
heaven and became a star, and the other, as a spirit,
took flight for the Reinga. The Reinga is, nowa-
days, sometimes mentioned as the Elysium of the
departed, and is also given to the rock on the north
shore of New Zealand from which the Maoris
believed the spirits leaped into the sea on their way
to this Elysium. Little difficulty, apparently, was
experienced in passing from the surface of the
ocean to the portals of these happy regions. In most
mythologies the way to spirit land is usually depicted
as being long and painful. Southey, in his " Songs
of the American Indians," for example, describes
the dread path which has to be trod by the Hurons:
To the country of the dead,
Long and painful is thy way !
O'er rivers wide and deep
Lies the road that must be passed,
By bridges narrow-wall'd,
When scarce the soul can force its way,
While the loose fabric totters under it.
War remained one of the chief employments in
the olden-time Maori heaven, though how results
were established in the matter of deaths and
victories does not appear. A Wesleyan missionary,
in The Missionary Register for 1826, relates a lively
conversation which took place between him and
several Maoris on the twin subjects of heaven and
hell. He says : " On telling them about the two
eternal states, as described in the Scriptures, one of
the number, an old chief, began to protest against
these things with all the vehemence imaginable, and
said he assuredly would not go to heaven, nor
would he go to hell to have nothing but fire to
eat, but he would go to the Raing or Po, to
eat kumeras with his friends who had gone
before." Slaves were sacrificed on the death of
a chief, so that they might accompany his spirit, or
spirits. The Missionary Register for 1828 narrates
the story of a child having been drowned, when the
mother insisted upon a female slave being killed " to
be a companion for it on its way to the Reinga."
It only remains to add that these old beliefs are not
yet wholly extinct in New Zealand. The present-
day Maoris will seldom venture far from their homes
when the night is dark — spirits are then abroad.
Graveyards and the houses of dead chiefs are tapu ;
to desecrate them would bring affliction, possibly
death. Still, in the silence of night, when the cry
of a belated bird is heard out of the darkness, the
Maori will exclaim : " Ah ! there goes another spirit
to Te Reinga."
THE LATE ALFRED RUSSEL WALLACE.
As our frontispiece to the volume of " Knowledge "
for 1912 we gave a portrait of Sir Joseph Hooker,
whom science had recently lost, and who in the year
1858, with Sir Charles Lyell, shared the honour of
communicating to the Linnean Society the papers
relating to the production of varieties, races, and
species which contained " the results of the
investigations of two indefatigable naturalists, Mr.
Charles Darwin and Mr. Alfred Wallace."
Hooker died at the age of ninety-four and now we
choose as our frontispiece a portrait of Dr. Alfred
Russel Wallace, who has just passed away at the
age of ninety. The part which Wallace played in
the establishment of the theory of natural selection
is too well known to need any comment from us, but
we may remind our readers of one or two points in
his life. He was born at Usk in Monmouthshire,
on January 8th, 1823, and was eight years younger
than Darwin. He left Hertford Grammar School
in 1836, and helped his brother who was an archi-
tect and surveyor. In 1840 he began to take an
interest in natural history and travel, and while
he was a master at a school in Leicester he met Mr.
H. W. Bates and took up with him the study of
beetles. It was with Bates that Wallace started off
in 1848 to the Amazons, to gather facts towards
solving the problem of the origin of species.
In 1852 Wallace, who had left Bates a year or so
previously, returned to England, losing all his
collections owing to his ship being burnt, and spend-
ing ten days in an open boat. He remained in
England for a year and a half to publish a book on
his travels, after which he went to the Malay
Archipelago for nearly eight years. In February,
1858, while he was in the Moluccas, he got the first
idea of the survival of the fittest obtaining as
did Darwin a suggestion from Malthus's " Essay
on Population." The paper arising out of this,
Wallace sent to Darwin. It is well known that
with regard to some points Wallace differed from
Darwin, and he occupied himself in the later
years of his life with other matters than those
which are purely scientific, but into these we
need not here go.
Frontispiece to KNOWLEDGE, Volume XXXIV (1913).
From a photograph
Alfred Kussel Wallace, O.M.. LL.D., D.C.L., F.R.S.
A portrait taken about 1911.
by Hoppt'.
THE FACE OF THE SKY FOR JANUARY.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 87.
Date.
Jan.
Greenwich
Noon.
Sun.
R.A. Dec.
h. m. o
18 44'6 S.23'1
19 6*6 22'6
19 28*5 2i'9
19 50*0 21 *0
20 11*3 20 'o
20 32-3 i8'9
20 53-0 S.17'5
Moon.
R.A. Dec.
h. tn. o
22 37-1 S. 9'7
2 I2'0 N.17'4
6 50*7 N.27-6
11 309 N. 2-5
15 57-2 S. 25-6
20 46-5 S. 21 "2
o 29-3 N. 5-4
Mercury.
R.A. Dec.
17 44'7
18 i8'i
■8 5*'3
'9 27'i
20 2*4
20 37 '8
21 13*1
S23-8
*4"3
24 '3
23-7
22'5
2o'7
S.i8-2
Venus.
R.A. Dec.
h. m. o
18 i-5S.23'5
18 28*9 23*5
18 56-3
■9 23'5
19 50 '5
20 17*0
2.3 ''
22 '7
21 8
20*7
20 43'i S. 19-3
Mars.
R.A. De
h.
7 I2'9N.26'3
7 4"i
6 5-,-5
6 47 '4
6 40-3
6 34 '4
26-6
26*9
27*1
27 '2
27*2
6 3o'oN.27*2
Saturn.
R.A. Dec.
ti. m. o
4 46*0 N.20'7
4 44 '6 20'0
4 43'4
4 42 '3
4 4" '4
4 4°'6
20 '6
20*6
20'6
20 "6
4 40'! N.20'6
Neptune.
R.A. Dec.
57'I
S6'5
55 '9
55'3
54 '7
54 '=
53'6
N.20'3
20 '3
20*3
20"4
20*4
20"4
N.20"4
Table
Date.
Sun.
P B L
Moon.
P
Mars.
P B L T
Greenwich
Noon.
OOO
+ 2'I — 3*1 228*6
- C3 3'7 162-8
27 4*2 96*9
5-1 4-8 31*1
7*4 5'2 325'3
9*6 5*6 259'4
+ 11*8 — 6"o r93"6
0
— 20*4
-18-5
+ 44
-f-2i*7
+ ll'3
-14-2
-2i-8
0 0 oh. in.
— ifi"6 4*5*3 1829 0 6 ;//*
'7*7 4*4 "39*2 2 29-w
18*8 3*6 95'4 5 29 m
ig"8 2'8 51 '4 8 29 tn
20*7 2'2 7'3 11 30 m
2t"4 i"7 322*9 2 32 e
-21*9 +i*3 278*3 5 35 *
„ 16 „
P is the position angle of the North end of the body's axis measured eastward from the North Point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the centre of the disc. In the case of Mars, T is the time of
passage of Fastigium Aryn across the centre of the disc.
The letters tn, e, stand for morning, evening. The day is taken as beginning at midnight.
The asterisk indicates the day following that given in the date column.
The Sun begins its Northward March. Nearest Earth
3d 9h e. Its semi-diameter diminishes from 16' 17i" to
16' 15£". Sunrise changes from 8b 8m to 7h 44m ; sunset
from 3h 58m to 4h 43m.
Mercury is a morning star till 25th, but too near the Sun
for convenient observation. Semi-diameter 2J". Illumination
nearly full. In " Face of Sky for December " read " Mercury
is a morning Star," not " evening."
Venus is a morning star, but getting too near the Sun
for convenient observation. Disc practically full. Semi-
diameter 5". One degree N. of Mercury, January 14d 5h tn.
Superior conjunction, February 11th.
Table 89. Occultations of stars by the Moon visible at Greenwich.
Disappearance.
Reappearance.
Date.
Magnitude.
Mean Time.
Angle from
Mean Time.
Angle from
N. to E.
N. to E.
1914.
h. m.
h. m.
Jan. 2
Wash. 1574
7-0
4 5°«
13°
—
0
., 4
Wash. 56
67
8 48 «
29
—
—
„ 6 ...
Wash. 149
6-8
8 15 «
79
—
—
., 9
BAC 1648
64
10 16 e
64
II 27 e
291
,, 10
BAC 1746
6-5
5 10 m
92
6 Off*
277
» 11
BD + 27°u64
6-9
4 57 '"
90
—
„ 12
k Geminorum ...
3-6
7 45«
136
8 25 m
256
„ 12
BD + 23Qi9i3
6-4
5 18 c
98
6 I2<
280
„ 13
Wash. 635
6-6
—
9 I4«
210
„ 15
BD+u°22i7
7-0
—
—
3 34 >"■
3°3
„ 15
45 Leonis
5 8
5 0 m
174
5 42 '"
256
,, IS
p Leonis
3-8
7 22 111
97
8 13 '"
324
,, 16
BAC 4054
6.4
10 31 e
100
11 25 e
322
„ 17
Wash. 789
6-9
—
—
6 7 111
299
,, 20
BAC 4867
64
2 36 111
98
3 35 '"
321
,, 20
BAC 4879
61
3 7 «
102
4 1 1 in
3i8
.. 31
62 Piscium
6-1
9 1 1
92
9 55«
217
„ 31
8 Piscium
4-6
9 27 e
41
10 21 e
269
From New to Full the disappearances occur at the Dark Limb, from Full to New the reappearances.
457
458
KNOWLEDGE.
December, 1913.
The Moon.— First Quarter 4d lh 9m e ; Full 12d 5h 9mm ;
Last Quarter 19d 0h 30m m. New 26d 6h 34m m. Apogee
3d 9h e. Perigee 15" 6h e. Apogee 31d 5h e, semi-diameter
14' 48", 16' 17", 14' 47" respectively. Maximum Librations,
9d 6° E, 9d 7° S, 22d 7° N, 23d 5° W. The letters indicate the
region of the Moon's limb brought into view by libration.
E. W. are with reference to our sky, not as they would
appear to an observer on the Moon. (See Table 89.)
Mars is in opposition 5d 6h e. Nearest Earth on 1st,
distance 0-622. This is an unfavourable opposition as
regards distance, but favourable as regards planet's
declination. It will be seen that both hemispheres of Mars
are observable, but the Northern one is best placed. The
semi-diameter during January, diminishes from 7b" to 6£".
The unilluminated lune is on the East : its width increases
from 0 to rV'. The Planet is in Gemini : 2° N. of e, on 22nd.
Jupiter is invisible, being in conjunction with the Sun on
20th.
Saturn is very well placed for observation, having been in
opposition on Dec. 7th. Polar semi-diameter 9J". P. is
-4°-2; B-26°-7. Ring major axis 47", minor 21". The ring
is approaching its maximum opening, and projects beyond the
poles of the planet. It is interesting to measure the exact
amount of overlap. The absolute maximum opening will
occur on July 1st, but the Planet will then be too near the
Sun to see.
East Elongations of Tethys (every fourth given), 2d0h-0e,
10d lh-2m, 17d 2h-4e, 25d 3h-6m; Dione (every third given),
2d 2h-7e, 10d 7h-8e, 19" 0h-7m, 27d 5h-7w; Rhea (every
second given), 2d 2h-8m, lld 3h-5m, 20d 4h-3m, 29d 5h-0m.
For Titan and Iapetus E.W. mean East and West Elonga-
tions; I. Inferior (North) Conjunctions, S. Superior (South)
ones. Titan, 5d 6h -2m I.; 9d 2h -6m W., 13d lh-9m S.,
17d 4h-6m E., 21d 4h-2m I., 25d 0h-6w W., 28d 12b-0e S;
Iapetus, 6d lh-9e I., 25d lh-4e W.
Uranus is invisible, being in conjunction with the Sun on
28th.
Neptune is in opposition on the 17th. Semi-diameter 1".
Possessors of small telescopes may easily recognise it by its
motion, if they make a sketch map of the stars in the region,
and observe it night by night.
Westphal's Comet. — See the ephemeris given last month.
The R.A. will be some 20" greater than the ephemeris value,
the declination 4° less.
Meteor Showers (from Mr. Denning's List) :—
Radiant.
Date.
R.A. | Dec.
Jan. 2-3 ...
230 + 53
Brilliant shower, swift,
paths.
long
.. 3
156 + 41
Swift.
,, 11-25 -
220 + 13
Swift, streaks.
,, 17
295 + 53
Slow, bright.
„ 17-23 •■
159 + 27
Swift.
„ 25
I3« + 32
Swift.
„ 29
213 + 52
Very swift.
Double Stars
given
of
these
are
and Clusters. — The tables
given two years ago are again available, and reai
referred to the corresponding month of two years ago
Variable Stars. — The list will be restricted to two hours
of Right Ascension each month. The stars given in recent
months continue to be observable.
Table 90. Non-Algol Stars.
Star.
X Aurigae
i) Geminorum
V Aurigae
V Monocerotis
V Lyncis
R Lyncis
S Canis Min. ...
V Geminorum
S Geminorum
U Puppis
Right Ascension.
h.
m
6
6
6
10
6
18
6
18
6
22
6
S4
7
28
7
36
7
3»
7
57
Declination.
+ 50 • 2
+ 22 -5
+ 47 -8
-2-1
+ 6l '4
+ 55 '5
+ 8-5
+ 20 -7
+ 23 -7
— 12 6
Magnitudes.
8-1 to 130
3'3to 42
83 10 ii- 7
7.7 to io- 2
8'6 to 9-4
65 to 14- o
7-7 to 12 7
8-5 to 9-2
83 to 145
8'5 to 145
Period.
d.
i62'6
233
352
332
72
379 '2
33o "3
286
293-8
315
Date of Maximum.
Feb. 4.
About January.
Dec. 22.
Jan. 7.
Feb. 1.
Mar. 27.
Dec. 21.
Jan. 27.
Feb. 4.
Dec. 16.
Principal Minima of /3 Lyrae Jan. 12d 7hm, 25d 5hw. Period 12d 21h -8.
Algol minima Jan. 7d 4h 5mm, 10d 0h 54mw, 12d 9h 42me, 15d 6h31me, 18d 3h 20me, 30d 2h 36mw.
Mira Ceti will reach maximum in March.
CORRESPONDENCE.
THE FLOWERING OF PLANTS IN SOUTH
GERMANY IN 1911 AND 1913.
To the Editors of " Knowledge."
Sirs,— Everyone knows the delights of botanists who, in the
month of August, have wandered through the Austrian and
Italian Tyrol. Edelweiss and Alpine roses form only a small
part of the treasures which they bring away, and they never
forget the fragrance of those Alpine meadows where the
flowers bloom and the bees fertilise them close under the ice
and snow. What is not generally realised is the wealth of the
Odenwald and the Schwarzwald especially so far as the fungi
are concerned, and these have been particularly abundant in
damp years, like 1912 and 1913. Unfortunately the orchards
and gardens have neither been so profitable nor so interesting.
So far as the plant-world of South Germany is concerned,
the annus mirabilis was the year 1911. The vineyards
were of more importance than the orchards. The grapes
were small but as sweet as sugar, and the tourist now in the
December, 1913.
KNOWLEDGE.
459
neighbourhood of Riidesheim and Eltville may deem himself
fortunate if the kindly host, who has his own vineyard, will
supply him with the vintage of 1911. To mix it with
Apollinaris, or any natural water, would be a crime.
The Spanish fruiterers, of whom there are many in this
part of Germany, had no need to import any fruit except real
exotics such as aubergines and pimientos. Quinces and
medlars were relatively extremely abundant. Peaches and
apricots were not only thoroughly ripe but also abundant,
and consequently so cheap that in some places they were
allowed to drop and rot upon the ground. It was worth a
walk of many miles out of the tourist's route to see in the
neighbourhood of Heilbronn the patient oxen drawing
wagon-loads of pumpkins which were like great balls of gold.
In Heidelberg and other towns of Baden it is extremely
common to see oleanders and pomegranates in public and
private gardens. They are often arranged in rows in front of
fashionable hotels, and now and again even in front of a
railway station. The blossoms on these were as profuse and
as beautiful as those I have seen in the warmest parts of the
South of Spain. Autumn blossoms, too, on the magnolias
were frequently seen, but this I find is not so rare. What
surprised me most was an avenue of horse-chestnuts from
which all the leaves had fallen, but the trees were covered
with recently opened blossoms. Again and again have I seen
horse-chestnuts, from which the leaves had fallen, covered
with new leaves, as though it were spring-time ; but here were
masses of blossom covering trees which were otherwise bare.
Is all this a development of buds recently formed, or a
development of the dormant buds of a previous year ?
This year has been worse than 1912, for the July of that
year was a warm month, whereas the heat this year has come
much too late. One peculiarity of the Neckar Valley is the
occurrence during the first fortnight of August of multitudes
of Ephemeridae, which are known there as August-Fliegen or
Weisse-Fliegen. Sometimes these are so abundant as to
fill the street lamps, and they are swept from the pavement
in barrow-loads, to be used afterwards as bait for fishing in
the Neckar. This year the little white flies have never been
seen. The pomegranates and oleanders have not blossomed,
the grapes are not sugar-sweet, and apricots and some other
fruits will never ripen. The fruiterers must import what they
want from Spain or the South of France, or depend in part
upon fruits which have been ripened under glass.
One thing which I have just seen is worth mentioning. Not
far from the dusty road which runs parallel to the Neckar
between Hirschhorn and Eberbach there is an apple-tree in
full blossom. Now what is the cause of that ? Certainly not
the warmth of the season. It is not the sun which has wooed
those blossoms from the buds. What one would like to know
is, what buds have been developed, and what will, in all
probability, be the history of that tree in the near future ?
76, Neuenheimer Landstrasse,
Heidelberg.
E. J. DUNGATE.
FRESH WORLDS TO CONQUER.
To the Editors of " Knowledge."
Sirs, — The other day when reading a scientific work (Mr.
Soddy 's excellent little book on Matter and Energy) I came across
the expression, " There is no fear that Science will yet awhile
be sighing, like Alexander, for fresh worlds to conquer." I am
happy to believe that this is true of Science ; but I strongly
object to having such a worse than childish aspiration put into
the mouth of one of the most highly educated heroes this
earth has ever seen. No doubt hundreds have said the same
thing before Mr. Soddy, and hundreds will say it again. But
no amount of repetition will make the phrase other than what
it is, namely, not only false, but the very reverse of what is
true, a piece of arrant nonsense and an insult to the memory
of a great man, who certainly had his faults, but who never
could have accomplished such wonders had his hold on the
reality of things been less steadfast and complete. And
precisely the fact that so eminent an authority as Mr. Soddy
should repeat the absurdity shows that the time for correcting
it has arrived.
Alexander did not conquer this world, and was perfectly
aware that he had not done so by a long way. It was with
bitter grief that he turned back from his Indian expedition in
deference to the remonstrances of his army. He must have
known, like every other Greek, that the Adriatic limited his
power to the West, that Italy, Sicily, and Carthage still
remained unsubdued, that his fleets had not doubled the
southern cape of Africa, long known to be circumnavigable,
nor even sailed to the Pillars of Hercules. And the interest-
ing thing, not merely for his biographers, but for the history of
science, is to read the true story which has been converted by
an almost inconceivable blunder into the false story commonly
circulated.
The true story runs as follows in the version given by
Plutarch :
" When Alexander heard from Anaxarchus [a philosopher
from Abdera] that there were an infinity of worlds, he burst
into tears, and on being asked what ailed him replied, ' Is it
not deplorable that while there are infinite worlds we should
not yet have made ourselves masters of this one world ? ' "
Plutarch tells the story, not where we would expect it, in his
Life of Alexander, but in his Moral Anecdotes, though what
particular lesson we are expected to draw from it does not
appear. Perhaps it was the same as that suggested to
Tennyson, when after looking through a telescope at the great
star-cluster in Perseus, he observed, " One doesn't think much
of the county families after that." Anyhow, the interesting
thing to find is that, contemporaneously with the strictly finite
world of Aristotle, Alexander's own teacher, revolving con-
centrically round our Earth, and enclosed by the outermost
solid star-sphere, conceived as a single body rotating once in
about twenty-four hours, the older and much truer Ionian
idea of infinite worlds should still have prevailed.
Thus by a path the reverse of Hamlet's we may follow in
imagination the noble dust of Alexander, or at least of
Alexander's table-talk, until it mingles with the star-dust of
the Milky Way.
ALFRED W. BENN.
THE PARTIAL ECLIPSE OF THE SUN, 1913,
SEPTEMBER 29.
To the Editors of" Knowledge."
Sirs, — This phenomenon5" was observed at the Union
Observatory, Johannesburg. At the time of sunrise a low-
lying bank of heavy clouds extended along the Eastern horizon,
but the sun began to appear above these clouds six minutes
after the calculated time of sunrise. The first appearance of
the sun was a very interesting sight. The eclipse was then
about at its middle phase and the sun, as it rose above the
cloud-bank, was exactly like a lion's claw. When the sun was
clear of the clouds it was possible to trace the dark outline of the
moon against a slightly lighter background for nearly a minute
of arc beyond the sun. This projection of the moon was
observed in the neighbourhood of both cusps of the sun. The
observation was made with a three-inch refractor through a
rather light dark glass. Definition throughout was too poor
to enable irregularities on the edge of the moon to be seen.
The last contact was observed at 16h 32m 50s Greenwich time.
(Mrs.) H. E. WOOD.
Union Observatory,
Johannesburg,
South Africa.
See Figure 536, page 452.
SOLAR DISTURBANCES DURING OCTOBER, 1913
By FRANK C. DENNETT.
October has proved more interesting to the solar observer
than any month since December last. Only one day was
missed, October the 5th. On seven days (4, 9 to 11, 13, 21,
and 30) the disc appeared free from disturbance, and
on nine others (1 to 3, 14 to 18, 22 and 23,) only faculae were
visible. It is to be remarked that the greater part of the
faculae and the whole of the dark spots were displayed in the
northern hemisphere. The longitude of the central meridian
at noon on October 1st, was 1° 24'.
No. 12. — A pretty group of tiny pores first seen on the 6th,
which in the afternoon were ranged like segments of two
interlocking eclipses. On the 7th only the rear portion was
seen, whilst on the 8th only a grey facula-lipped pore
remained which was gone next day. Its maximum length was
35,000 miles.
No. 13. — Two pores, the larger preceding, almost in the
centre of the disc, only seen on the 12th.
No. 14. — A small bright facula having two penumbraless
pores, one on either side, east and west, seen on the 19th,
when the disturbance showed hydrogen flocculi, and the dark
Ds line of helium with the spectroscope. Next day the facula
was still traceable with minute pores but they were not seen
after.
No. 15. — On the 24th a group of pores was visible a little
within the northeastern limb amid brilliant faculae. The
components remained small, and were subject to much
change until last seen on the 29th. Its greatest length was
72,000 miles.
No. 15a. — On the 31st there was a dark grey "veiled"
spotlet a little north of the area which had been occupied
by No. 15. It was not, however, seen afterwards.
Faculae like tiny bright granules were visible within a few
degrees of the North Pole, on October 1st to 3rd, 6th, 15th,
16th, 24th and 25th. A small one was noted at longitude 28°,
S. latitude 40°, on the 3rd. Faculae were also noted near the
south-west limb on the 11th, and the north-east on the 14th.
On the 16th a faculic knot was at longitude 217°, S. latitude
33°. On the 17th and 18th a faculic knot seen at 87°, 38° N.
(near the north-east limb), and a bright streakiness near 77°,
25° N. Traces of the former still showed on the 20th, as well
as a pale patch within the eastern limb a little north. Pale
faculae a little within the eastern, and nearing the south-
western limbs on the 22nd. Also within the north-eastern
limb, at 351°, 15° N. on the 23rd and 24th. Within the
eastern limb a faculic knot was visible on the 31st.
Our chart is constructed from the combined observations of
Messrs. J. McHarg, A. A. Buss, C. Frooms, E. E. Peacock,
and the writer.
DAY OF OCTOBER, 1913
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210 240 250 240 270 280 30 300 310 320 330 340 350 ■
NOTES.
ASTRONOMY.
By A. C. D. Crommelin, B.A., D.Sc, F.R.A.S.
DETERMINATION OF RADIAL VELOCITIES OF
FAINTER STARS.— It has often been felt that it would be
of great importance in advancing our knowledge of the
structure of the universe, if spectrograms taken with an
objective prism could be used in the determination of radial
velocities. The results with the slit spectroscope are
splendid in their marvellous accuracy ; but owing to the great
loss of light at the slit, and the resulting length of exposure,
the method is practically limited to the naked-eye stars, or
those not much below this limit. When the method of the
prism before the object glass, without any slit, is employed,
there is no loss of light, consequently much fainter stars can
be reached with a moderate exposure ; also there are many
spectra on each plate, so the work of making a spectroscopic
Durchmiisterung is rendered possible. In fact, much progress
has been made with this at Harvard, but hitherto attention
has been paid merely to the type of spectrum, not to motion
in the line of sight. Suggested methods of doing this were
given by Professor Pickering and others ; these are now
discussed by Dr. Schlesinger in Proc. Amer. Phil. Soc,
Vol. LII, No. 209. He considers two methods practicable for
obtaining fairly accurate results. The first consists in
measuring the distance between two known lines in each
spectrum. With prismatic spectra the effect of velocity in the
line of sight is much greater for the violet end of the spectrum
than for the red. Hence stars approaching us have their
spectra lengthened, those receding have them shortened.
Plates are now available that will photograph the red end of
the spectrum with moderate exposures. It is desirable to use
a Cooke Triple object-glass, or else to have one specially
designed to bring the required regions into focus together.
The author also recommends the use of a temperature case
surrounding the whole apparatus, as change of temperature
affects the sharpness of the spectra. He also advises taking
check plates every night on stars whose velocity is already
known by the slit method. With these precautions results of
considerable accuracy may be expected.
The other practicable method is that of placing a screen of
neodymium chloride before the plate. This artificially
introduces some absorption lines into the spectrum, one of
which, at X 4272, is stated to be suitable as a comparison line.
460
December, 1913.
KNOWLEDGE.
461
He does not recommend this method except for stars of types
A and B (Sirius and Orion). In solar and red stars the
artificial line is confused with stellar lines.
He gives a third method, but as he considers it less hopeful
I do not describe it.
In the case of object-glasses too large to cover by objective
prisms, he suggests the use of an auxiliary lens, placed in
the cone of rays from the objective, so as to give a smaller
pencil of parallel light than that falling on the objective. In
this way a smaller prism will suffice, without sacrificing any of
the aperture.
It goes without saying that a less degree of accuracy is
expected than with the slit method. But what is desired is
not so much the exact motion of individual stars as averages
for large groups of stars of different types,
and distributed over the sky. For this
purpose the new methods are full of promise.
c*
*.
• a
COMETS. — In recent years, the autumn
has been the great time for comets, and this
year has been no exception ; four comets,
three of them periodic, have been under
observation. Westphal's is the most impor-
tant, from its association with Neptune. It
presented an interesting appearance early in
October, being easily visible in an opera
glass (so that Mrs. F. Wilson found it
without knowing of its previous discovery)
and having been glimpsed with the unaided
eye. However, it did not live up to this
early promise. It grew faint and diffused, in
spite of its approach to the Sun, and by the
end of October was very difficult to see.
On October 22nd it passed within half a
degree of Metcalf's comet, and the unusual
spectacle was afforded of two comets in the
same field. Both were then of the ninth mag-
nitude. As Westphal's is not at perihelion till 3 p.m. on
November 26th, it is quite likely that there may be another
outburst of activity. This uncertainty about the physical
behaviour of comets adds interest to their study. During
December Westphal's will be about 40' south of the ephemeris
given last month ; the R.A. will be a minute or more in excess
of the ephemeris. Corrected elements by Miss Levy :
Omega 56° 31' 36", Node 346° 47' 45", inclination 42° 33' 7",
Period 61-121 years, Log. q. 0-1012, Log. a. 1-1908.
Neujmin's comet was interesting in two ways ; first for its
appearance. It was exactly like a small star with a faint
nebulous appendage to the south-east. This stellar appear-
ance enabled its position to be fixed with great accuracy.
Herr Stracke has computed the following orbit. Perihelion,
1913, Aug. 16-31 Berlin, Omega 346° 7' 52", Node 357° 54' 19"
inclination 14° 52' 34", eccentricity -7786, Period 18-16 years ;
perihelion distance 1-5300, aphelion distance 12-288.
The comet appears to belong to the group that owns
allegiance to Saturn. Two other members of the group are
known. One is Tuttle's comet, the other was discovered by
Peters in 1846, but has never been seen since. It is to be
hoped that the period of the present comet will be accurately
determined, to facilitate its recovery at its next return.
A comet discovered by Dr. Zinner at Bamberg, 1913 e, is
identical with Giacobini's comet, 1900, III, the period being
6-465 years. Perihelion passage is 1913, November 2-30,
Omega 171° 32', Node 193° 0', inclination 32° 17' log. q. 9-9961.
Owing to its rapid southerly motion it will soon be out of
reach of European observers.
THE ANDROMEDA NEBULA.— Lowell Bulletin No. 58,
contains an investigation by Mr. V. M. Slipher on the radial
velocity of this nebula. It has been known for some years
that there were some Fraunhofer lines in its faint continuous
spectrum. He secured four plates last autumn and winter
with exposures of about seven hours each, and obtains the
startling result that the nebula is approaching us at the rate
of 297 kilometres per second, the individual values being 284,
296, 308, 301. It is a little difficult to credit that such a vast
Figure 537.
Neujmin's Comet as sketched by
Prof. Barnard. 1913, Sept. 9th.
Star a is Nicolaiev 5064, mag. 8.3 ;
b is of mag. 11.7 ; c, 11.4 ; comet,
11.5. The distance a-c is 4|*,
South is at the top.
object as this nebula (certainly several light-years in length)
can be moving bodily with such inconceivable speed, and the
results will doubtless be discussed by skilled spectroscopists,
to see if there is any other explanation of the shifts of the
lines. Mr. Slipher notes that the shift in the violet was twice
that in the blue, which accords with the supposition that it is
due to velocity. If it really has a speed of this order, its
distance must be very great, or it would have a sensible
proper motion ; for the direction of motion is not likely to be
exactly radial.
I have lately been examining the photographs of this nebula,
and it appears to me that there are far more cases where
curves of stars mark out and follow the shape of
prominent portions of the nebula than we can reasonably
attribute to chance. In my view these
stars are actually associated with the nebula.
If this assumption is true it is of twofold
importance ; first, it would dispose of the
theory that the nebula is an external galaxy,
for these stars are exactly like those forming
the background of the sky in ordinary
regions, and obviously belonging to our
galaxy. Secondly, these stars could be
examined for parallax and proper motion
much more easily than the nebula itself,
since its outlines are vague. The case of
the Orion nebula may be recalled ; Sir W.
Huggins considered it established that the
stars forming the Trapezium were actually,
not merely optically, associated with the
nebula, so that they could be examined for
parallax and proper motion, instead of the
nebula itself; the soundness of this view is
generally admitted.
.y>,'.';.:-':?;5>i
JSStt
CAMPBELL'S "STELLAR MOTIONS,"
AND SIR DAVID GILL'S "HISTORY
OF THE CAPE OB S E RVATO RY."— These two
books have lately appeared. The first, which is the
" Silliman Lectures, 1910" should be read by all who
desire an intimate acquaintance with the marvellous precision
of modern spectrographic work, especially as applied to
motion in the line of sight, and the countless precautions
that are taken to avoid systematic errors in the results. In
our own system the method has been applied to various
problems : the rotation of the Sun, Venus, and Uranus, and
the optical verification of the fact that Saturn's ring is com-
posed of small particles with independent motion. In the
stellar heavens the method has given a new determination of
the direction and speed of the Sun's motion ; it has given
great help in forming estimates of the distances of various
classes of stars, and in demonstrating the unexpected fact
that the speed of a star increases as its spectral type advances.
Its application to the study of Algol variables and those of the
Beta Lyrae, Cepheid and Geminid types, are also dealt with,
and some interesting conclusions are drawn from statistics of
spectroscopic doubles.
Sir David Gill gives a resume of the important problems
with which the Cape Observatory has been associated. The
distances of the Sun, Moon, and Stars, Jupiter's satellites, The
Cape Photographic Durchmusterung, double stars, spectro-
scopic work, the survey of Africa, are all dealt with. I hope
to give some further notes on this book in a future month, but
in the meantime I recommend our readers to study it for
themselves.
DISTRIBUTION OF CLUSTERS AND NEBULAE.—
Dr. Charlier, of Lund, has published some statistics in tabular
and graphical form of the distribution of clusters and nebulae
in various regions of the sky : they are based on the three
catalogues of Dreyer, containing 13,223 objects, of which 769
are clusters. The clusters show an unmistakable tendency
to congregate along, or near, the Milky Way. This seems to
show that most of the clusters are actually involved in the
star-clouds of the Milky Way, and are consequently extremely
distant. The individual stars may therefore be very much
462
KNOWLEDGE.
December, 1913.
larger, and the degree of compression very much slighter, than
we are apt to imagine from their telescopic aspect.
The nebulae, on the other hand, show a decided avoidance
of the Milky Way and an aggregation towards its poles,
especially the northern one in Coma Berenices. He has
divided the nebulae into various classes according to size,
shape, and brightness, but the same general arrangement
persists. He has not grouped them according to spectral
type (the distinction between "white" and "green" nebulae),
though this difference is more significant than the others. It
has been suggested that the paucity of nebulae along the
galaxy arises from the brightness of the sky background, and
the consequent difficulty of detecting faint nebulous objects.
However, even the bright nebulae cluster very definitely round
the Coma Berenices pole. There is no such marked aggrega-
tion of them at the opposite pole.
On the whole it looks as if the Galaxy had some influence
on the distribution of nebulae ; if so, the greater part of them
belong to our own stellar system, and are not external
universes. This is also supported by the comparatively small
radial velocity indicated by those whose spectra have been
carefully observed. We should expect independent universes
to have considerable motion relatively to each other, and so to
show large radial velocities. Those actually found are of the
same order of magnitude as those of the stars.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S
BOTANY AT THE BRITISH ASSOCIATION
{continued). — Apart from the Presidential Address given by
Miss Sargant, the only notable paper of wide interest was that
by Professor Reinke, " On the Nature of Life." The veteran
Kiel botanist protested against the view that life can be
interpreted merely mechanically, and urged that the greater
the progress in experimental physiology, the better we learn to
use our knowledge of non-living matter for the explanation of
the processes of life, the more we understand that a complete
physico-chemical analysis is impossible for any important life
process. Behind all the physico-chemical facts ascertained
by physiological studies there hides an unknown factor, " an
* not to be solved by levers and screws and chemical
reagents." He maintained that although the laws of energy
are valid in the organism as well as in unorganised nature,
life being based on transformations of energy or "elementary
processes," these processes are not thrown together without
order in the living body, but are united by an invisible chain
which maintains order among the elementary processes and
represents the true difference between life and any event in
lifeless nature. This " life principle " is, unlike the single
elementary processes, inaccessible to physiological analysis ;
it is " no force or power, it is a principle of succession, of
order, of regulation, of harmony."
An interesting " semi-popular address " was given by
Professor W. H. Lang on epiphyllous plants — chiefly algae,
lichens, and liverworts — which grow in a non-parasitic manner
on the foliage of trees in very damp tropical forests. He
pointed out the prevalence in such forms of an efficient means
of attachment to the surface of the leaf, and laid stress upon
the occurrence of flat disc-like early stages in the germination
of the spores of epiphyllous liverworts as an adaptation to this
mode of life.
Among various other contributions on the morphology and
biology of cryptogams the following may be mentioned.
Professor West read two papers dealing with his observations
on the genus Microspora and on Zygnema ericetorutn : in
the former he pointed out that the isolation of Microspora in
a special order (Microsporales) of the Green Algae should be
given up. Dr. Darbishire described the development of the
apothecium in the lichen Peltigera, in which male organs
(spermatia) are very rare, though fruits are formed abundantly,
probably by apogamy ; no coiled carpogonia can be made out,
but there are deeply staining cells which form part of a connected
system of branched hyphae proceeding from medulla to cortex,
becoming multinucleate by nuclear divisions in the cells
and (after producing functionless trichogynes which force
their way through the cortex) giving rise to large cells
(" ascogonia ") from which the asci derive their paired female
nuclei. Miss E. M. Poulton described the structure and life
history of an aquatic lichen, Verrucaria margaracea. In an
interesting paper, illustrated by very fine lantern slides,
Professor Buller described the structure of the gills in
the toadstool genus Coprinus, with special reference to the
beautiful adaptations shown by the basidia of varying lengths,
bearing the spores at different levels, and thus ensuring the
liberation of spores in the most efficient manner. The same
genus was dealt with by M. L. Baden, who found that, after
encountering great difficulty in germinating the spores of
Coprinus sterquilinus on ordinary media, vigorous germina-
tion occurred in media containing abundant bacteria, leading
to the conclusion that in some way the bacteria are of benefit
to the spores and to the mycelium formed by theirgermination —
possibly by producing substances which soften the spore coat,
or by removing any by-products of the fungus which may
hinder germination. The apple-canker fungus, Nectria
ditissitna, was described by S. P. Wiltshire, who found that
this fungus, which is a genuine wound parasite, can only
attack trees when the injury is deep enough for the fungus to
reach the wood, and that in nature the chief means of inocula-
tion are injuries made by frost and by the woolly aphis
(Schizoneura lanigera), in both cases the bark being burst
by the swelling of the various tissues ; the reactions of the
host against the disease are the formation of phellogen at the
limits of the infected region in the cortex, of abnormal wood
similar in structure to the medullary rays, and of wound gum
in the wood vessels. Miss M. Hume described the structure
of the leptoids, or " sieve-tubes," of the moss genus Poly-
trichum, pointing out that these cells have a nucleus though
never containing starch grains or large oil drops like the other
living cells of the moss stem. Direct experiments indicate that
the conducting function of the leptoids is probably confined
to albuminous materials and is not concerned with carbo-
hydrates, the latter being possibly conveyed by the hydroids
which probably have not a purely water-conducting function.
Dr. R. R. Gates presented and discussed certain evidences
to show that mutation and Mendelian splitting are different
processes. Results have been obtained showing that some
at least of the mutations of Oenothera are not due to
recombinations of Mendelian characters, as some writers have
assumed, but to irregularities in the reducing nuclear division
(" meiosis ") which lead to changes in nuclear structure. The
cases of O. lata and O. semilata alone were referred to in
this paper, because they offer a means of differentiating
between characters which are inherited from the parents and
those which arise as a result of unequal or irregular distribu-
tion of the chromosomes during meiosis : these mutant forms
have fifteen chromosomes instead of fourteen, and the same is
true of all individuals possessing the foliage and habit of lata
or semilata, even when these characters are associated with
others derived by inheritance from their parental forms.
Such cases show definitely that mutation is a process which is
independent of the recombinations of characters such as
occur in hybrids. The source of the fifteen chromosomes was
shown some years ago to lie in occasional irregularities in the
distribution of the chromosomes during reduction ; two pollen
grains of a pollen tetrad receive eight chromosomes, and the
other two receive six, and when an egg having seven chromo-
somes is fertilised by a male cell from a pollen grain
with eight, the resulting individual will have fifteen
chromosomes and the foliage of lata or semilata. The extra
chromosome, which is a triplicate of a pair already
present, is thus associated with the development of certain
foliage characters in Oenothera in the same way that the
accessory chromosome, when present in duplicate, is, in
certain insects, associated with the development of female
sex characters. This is apparently the first case in plants in
which a definite relation has been shown to exist between a
chromosome and particular external characters.
Physiology was represented mainly by a joint discussion
December, 1913.
KNOWLEDGE.
463
with the Chemistry Section, which was opened by Professor
Moore with an account of various methods of bringing about
the synthesis of formaldehyde from carbon dioxide and water
by inorganic colloids acting as transformers of light energy ;
and by a paper in which Mr. W. N. Jones described some
recent investigations in pigment (anthocyan) formation.
Ecology was represented by three papers on maritime
vegetation. Professor Oliver dealt with the distribution of
Suaeda fruticosa and its role in the stabilising of shingle,
pointing out that while all shingle plants to some extent
modify or retard the landward movement to which shingle
beaches are liable, when very high tides are accompanied by
onshore gales, Suaeda fruticosa, from its shrubby habit of
growth and high capacity of rejuvenescence, is the most
effective stabiliser of all British shingle plants. Miss W. H.
Wortham described some features of the sand dunes in the
south-western corner of Anglesey, with special reference to
the succession of the various plant associations ; while Mr.
P. H. Allen gave a preliminary account of the observations
made by a party from the Cambridge University Botany
School on the maritime plant associations at Holme, Norfolk,
the chief feature of the area being a sandy salt marsh, though
there are also sand dunes and shingle banks.
CHEMISTRY.
By C. Ainsworth Mitchell, B.A. (Oxon.), F.I.C.
ACTION OF ALKALINE WATER ON LEAD.— The
water consumed in Birmingham, which is mainly derived from
Wales, is slightly alkaline, and unless subjected to special
treatment has a pronounced action upon bright sheet lead.
To obviate risk of danger from this cause a small amount of
powdered chalk is added to the water in the Welsh reservoirs.
The results of experiments upon this solvent action of the
water are described by Messrs. Liverseege and Knapp in a
communication to the British Association.
In these experiments, which were continued over a period
of five years, it was found that different portions of a lead
pipe behaved differently in this respect, and that the resistance
offered to the water increased with the lapse of time. New
lead pipes were rendered more resistant to the action of
the water by treatment with a dilute solution of potassium
permanganate. The erosion of sheet lead by the water
depended upon the simultaneous action of oxygen, and its
degree varied with the distance of the metal from the surface.
Carbon dioxide had but little effect in preventing the action
of the water unless present in a quantity exceeding two per
cent, by volume. Under those conditions the erosion of the
lead was stopped, but the metal was dissolved in appreciable
quantities. An addition of lime in proportions within the
limits of three to nine parts per one hundred thousand
reduced the erosive action, but larger or smaller quantities
had little, if any, effect. The best results were obtained by
treating the water with not less than four parts of calcium
carbonate or not less than two parts of calcium bicarbonate
per one hundred thousand.
THE FIXATION OF NITROGEN BY FELSPAR.— A
mode of decomposing felspar, and its use in the fixation of
atmospheric nitrogen, is described by Mr. W. H. Ross in the
Journ. Ind. Eng. Chem. (1913, V, 725). If a current of
nitrogen be passed over a mixture of felspar and carbon
which has been heated to a temperature of 1400° C. only a
small proportion of the nitrogen is retained by the ignited
mass, but by adding calcium carbonate or lime to the mixture
a relatively large amount becomes fixed. In the reaction that
takes place the potassium of the felspar is liberated and
volatilised, and more nitrogen is fixed than would be required
to form a nitride of aluminium. For example, a mixture of
two parts of felspar, two parts of carbon, and 4-3 parts of
calcium carbonate when ignited at 1400° C. in a current of
nitrogen fixed 6-1 per cent, of nitrogen in one hour and 7*4
per cent, in two hours. The fixed nitrogen may be very
slowly liberated in the form of ammonia by boiling the
product of the reaction with water or with a solution of
sodium hydroxide.
THE FORMATION OF ALKALOIDS IN PLANTS.—
From the results of experiments upon Datura and tobacco
plants Messrs. Ciamician and Ravenna (Chem. Zeit., 1913,
XXXVII, 1156) have drawn the conclusion that vegetable
alkaloids may be formed from amino-acids. For example, green
tobacco plants normally contain about 0-15 per cent, of
nicotine, but by inoculating them with various organic
compounds the proportion of alkaloid could be more than
doubled. Thus, after treatment of the plant with pyridine
tartrate, the amount of nicotine was raised to 0-22 per cent.,
while with asparagin it was increased to 0-25 per cent., and
with benzoic acid and quinol up to 0-4 per cent. Dextrose
also led to an increased production of nicotine, whereas
phthalic acid caused the proportion to be less than normal.
Analogous results were obtained by treating Datura plants
with pyridine, piperidine and carbopyrrolic acids, the first of
these compounds causing the greatest increase in the alkaloidal
production. In the case of both plants there was complete
assimilation of the added substances.
ABSORPTION OF OXYGEN BY COAL.— An investiga-
tion that has an important bearing upon the spontaneous
ignition of coal has been made by Mr. T. F. Winmill (Times,
Eng. Suppl., Oct. 1st, 1913). In each series of experiments
coal-dust from coal taken from different parts of the Barnsley
seam was exposed to the air at a temperature of 30° C. and the
rate of oxidation determined. It was found that during the
first hour or two the rate of absorption of oxygen was very
rapid, and that the quantity absorbed was approximately
proportional to the nature and amount of the carbonaceous
matter present. As much as a tenth of a cubic centimetre of
oxygen was absorbed by one hundred grammes of the coal
dust during this initial oxidation, which lasted about forty-eight
hours. The speed of absorption then became much slower,
but it was possible for the increase of temperature produced
during the first stage of oxidation to accelerate the velocity of
this second stage to such an extent that, given favourable
conditions, there was risk of ignition taking place. The
reduction of the proportion of oxygen in the air did not
prevent the initial oxidation, while the use of coarser coal-
dust having only one four- hundredth of the surface of the fine
dust only reduced the speed of oxidation by 28 per cent. A
rapid increase in the velocity of the absorption followed each
increase of the temperature.
MICRO-ORGANISMS PRODUCING ARSINE— The
conditions under which it is possible for arseniuretted
hydrogen (arsine) or similar products to be liberated from
compounds of arsenic are matters of considerable importance
from the public health point of view. Although wall-papers
coloured with an arsenic green are not so common as was
once the case, they may still be found, and, when exposed to
the air, may yield poisonous volatile compounds. At one
time it was commonly believed that cases of poisoning by
arsenical wall-papers were due to the dry dust given off from
the surface, but in 1908 it was proved by Gosio that the real
cause was an organic compound of arsenic produced by the
action of certain mould-fungi in the presence of the carbo-
hydrates contained in the paste by which the paper was
attached to the wall.
This action is strictly specific, and was shown by Neppe
(Scienza Pratica, 1908, I, 82) to be a characteristic property
of the following moulds, arranged in the order of decreasing
activity: — Penicillium brevicaule, Aspergillus clavatus,
A. fumigatus, A. glaucus, A. virens, and Mucor mucedo.
A certain degree of moisture is necessary for the action of
the mould-fungi, and a temperature of about 25° C. (77° F.)
promotes the decomposition, which appears to be a direct
vital phenomenon. When the amount of arsenic present
exceeds a certain proportion the mould-fungi themselves are
poisoned, but they can be gradually rendered immune to
larger quantities. The volatile compound set free was found
by Neppe to be diethyl-arsine, HAs (C2Hj)2.
A further investigation of the moulds capable of decom-
posing arsenical compounds in this way has recently been
made by Dr. Husz (Apoth. Zeit., 1913, XXVIII, 605). The
464
KNOWLEDGE.
December, 1913.
behaviour of ninety different mould-fungi was investigated,
and it was found that two forms of Aspergillus and five
forms of Penicillium were the chief micro-organisms
possessing this property. Among the moulds growing on
arsenical paint on the damp walls of a room there was also a
variety of Actinomyces, which appeared to be of common
occurrence. When grown on culture media this mould
formed colonies of a chalk-white appearance, owing to the
production of spores.
ATOMIC WEIGHT OF CHLORINE.— Two critical
studies of the published determinations of the atomic weight
of chlorine are given in the Chem. Zentralblatt (1913, II,
572). In the first of these by Dr. A. Guye, the collated
results obtained by the classic method of precipitating the
chlorine with silver give the atomic weight as 35-454, this
value being dependent upon the atomic weight of silver, which
is taken as 107-57 to 107-88. By the more modern method
of calculating the atomic weight from the vapour density,
chlorine shows the value 35-461, which corresponds to an
atomic weight of 107-89 for silver. The calculations of M. E.
Wourtzel are in substantial agreement with those of Dr. Guye.
Taking the atomic weight of hydrogen as 1-0076 and that of
nitrogen as 14-008, the corresponding atomic weight of
chlorine was found to be 35-460.
ENGINEERING AND METALLURGICAL.
By T. Stenhouse, B.Sc, A.R.S.M., F.I.C.
CORROSION OF CONDENSER TUBES.— Sir Gerald
A. Muntz, Bart., and Professor H. C. H. Carpenter, M.A.,
Ph.D., the Chairman and Hon. Secretary respectively of the
Corrosion Committee of the Institute of Metals, have prepared
a statement of a further scheme of work planned by the
Committee. A short summary of the experimental work
already accomplished was given in the last number of
" Knowledge." The new work to be undertaken includes
a time-temperature survey of the conditions under which
dezincification of condenser tubes can take place, and a more
detailed study of the temperatures existing in the experimental
condensing plant and other condensers. Special attention
will also be directed to the conditions under which electro-
chemical protection can be effectively maintained, and in this
connection a comparative study of all the principal methods
of holding tubes in tube-plates will be carried out. A
systematic series of experiments will also be initiated with
a set of tubes of a copper-aluminium alloy from which
specially interesting results are anticipated. The work will
be carried out by Dr. G. D. Bengough, M.A., the Hon.
Investigator, the expenses being met by subscriptions to the
Corrosion Research Fund of the Institute of Metals. The
contributions received to date since the establishment of the
fund in January, 1911, amount to nearly £800.
BRITISH ASSOCIATION— SECTION G.— The report
of the Committee to Section G of the British Association, on
" Certain of the more complex stress distributions in Engineer-
ing Materials," gives a review, with bibliography, of the
literature dealing with combined and alternating stresses. In
notes contributed by Dr. F. Rogers, the usual causes of the
failure of metals under alternating stress are summarised in
the three main classes: — (a) Flaws, including pipes, fissures,
blow-holes, impurity, and non-metallic enclosures. (6) Faulty
original heat -treatment of pure metal. This includes as a
special case, strains set up in manufacture, and overwork in
the working processes, (c) Under-estimation of stresses to
be expected, on the part of the designer. This includes as a
special case insufficient allowance for the effect of repetition
of a stress which would be harmless if applied once or steadily
maintained.
The Heat Treatment of steel, as affecting endurance, may
conveniently be considered in three main classes: — (1) Over-
heating, which must be distinguished from "burning," in
general, diminishes the endurance under alternating stress.
(2) Reheating through the critical range is, in general,
capable per se of bringing the endurance to a normal high
value. (3) The speed of cooling through the critical
range has in any event a most profound influence upon the
endurance under alternating stress. Generally speaking, it
appears that the more rapid this cooling the greater is this
endurance.
GEOGRAPHY.
By A. Stevens, M.a., B.Sc.
FIORDS. — The work on the Nature and Origin of Fiords,
just published by Mr. Murray for Professor J. W. Gregory,
will arouse much interest. Fiords have generally been
ascribed to glacial action, but Professor Gregory advances
reason for believing that they are the result of earth-
movements and faulting, and succeeds at least in discrediting
the glacial hypothesis. First of all, it is not true that fiords
occur only in glaciated regions, for typical fiords occur in the
unglaciated areas of Dalmatia and the North Island of New
Zealand. Then it is certain that at least the Scottish fiords
are pre-Glacial in age, and the direction of glaciation is often
transverse to the line of the fiords, as is shown remarkably in
the Shetland Isles, where the ice movement was from east to
west, while the inlets are strikingly arranged in a north and
south direction. Taking the Scottish lochs for example, they
are seen to follow four well-marked sets of lines, trending
north-east, north-west, east, and north. Fissure-systems
running in these directions are frequent and typical in
Scotland. Of these the first is the most striking, and the
Caledonian Canal with its line of lochs, and the persistence of
the line in the northern shore of the Cromarty Firth and the
coast of Sutherland and Caithness, is the most remarkable
example. This system is dependent on the well-known
Great Glen fault. In the north-west system the branch
of Loch Awe, for instance, runs in the Pass of Brander,
which is also a fault valley. Then the arrangement
of fiords is not that which a glacier system would
produce. There is no hint of radiating from central high
land that would inevitably be seen in features due to ice, and
side fiords join a main fiord of one system from directions
that associate them with other systems. It is not only in
Scotland that the fiords are associated with the ascertained
crack-systems of the country. The phenomenon is seen in
Spitzbergen, Dalmatia, and in the other regions described.
The distribution of fiords is significant and correlated with
the different types of movement characteristic of polar and
equatorial regions. They occur mainly on western coasts
where the piling up of elevations of the earth's crust is
greatest, and just beyond which has taken place extensive
foundering ; and this distribution is dependent on the rotation
of the earth. The crack-systems are associated with the
foundering of the ocean-beds. Two fiord belts exist, the
northern nearer the pole than the southern, on account of the
tetrahedral plan of the earth.. Along fiord coasts typical
fiords are found in the higher latitudes, and pass towards
the equator into fiards, which in turn give place to rias. In
the fiord regions themselves, in the higher latitudes, are wider
rift-inlets and sounds associated with typical networks of true
fissure fiords, and nearer the equator the wider rift channels
disappear, and only the fiord reticula remain. This succession
is wonderfully constant.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S.
CALCITE CRYSTALS FROM A WATER TANK.— In
view of the frequent occurrence of crystals of carbonates,
especially dolomite, in certain argillaceous sediments, the
observations of the late R. F. Gwinnell on calcite crystals
formed in a water-tank are of interest (Mineralogical
Magazine, July, 1913). The crystals were deposited in
sand-like heaps in a tank into which water was led, through an
old leaden pipe, from a spring in the ferruginous beds at the
base of the Marlstone (Middle Lias) to the north of Grantham,
Lincolnshire. They were formed during the dry summer of
1911, when the flow of water, although not ceasing, was
December, 1913.
KNOWLEDGE.
465
reduced to a mere trickle. Under microscopic examination
the crystals were found to be colourless, of rhombohedral
habit, and giving the usual tests for calcite. This determina-
tion was confirmed by chemical analysis, which showed that
the deposit contained 95 • 65 per cent, of calcium carbonate, the
rest being alumina, ferric oxide, and silica. The deposition
of these crystals under artificial conditions of comparative
aridity has a bearing on the formation of similar carbonate
crystals in ancient sediments laid down under arid conditions,
under which direct precipitation of carbonates from solution
may well have taken place.
LAND CLASSIFICATION AND GEOLOGY.— Recently
the people of the United States became aware that they had
been too lavish with their lands, and that more than half the
public domain had been alienated. Now, therefore, the
examination and classification of the public lands has been
made an essential preliminary to their disposition and develop-
ment, and the Geological Survey was commissioned to carry
out a scientific examination of the lands still remaining to the
nation. Pending the accumulation of this quantitative
knowledge the land is withdrawn from settlement and
exploitation ; but as soon as any area is accurately known, and
its highest use ascertained, it is restored to entry, and is so
disposed as to secure the maximum benefit to both settler and
State. From the results of geological examination by its field
officers the Land Classification Board of the United States
Geological Survey is enabled to say whether the highest
utilisation of certain areas may be attained by working
metalliferous deposits, coal, oil, gas, phosphate, or salines, or
by using it as a reservoir or water-power site, or merely as
agricultural land. On the basis of information thus obtained
the public-land administrative officers make the most useful
allocation of the land that is possible. In the case of coal a
most exact quantitative survey is made, and a valuation
becomes possible. After classification and valuation the
lands are restored to entry, and may be acquired under the
coal-land laws at the valuation prices. Prior to land-
classification many persons fraudulently obtained coal and
other valuable mineral lands under the cheap and easy mode
of entry relating to agricultural lands. The principles,
purposes, and methods of land classification are explained in
Bulletin 537 of the United States Geological Survey, which
makes most interesting reading. It presents a clear formula-
tion of a new method in which the science of geology is made
of practical value to the public. Although it is rather late in
the day to voice the sentiment it is perhaps a pity that all the
public land of our own country is so hopelessly alienated.
ORIGIN OF TEKTITES.— Under the term "tektite,"
Professor Suess includes all the peculiar pebbles of obsidian-
like glass which have been described under the names of
moldavite, billitonite, and australite. These have frequently
been assigned an extra-terrestrial origin ; and Dunn regards
australites as the blebs from the bases of glass-bubbles ejected
from volcanoes and distributed by the wind over the Australian
plains (see " Knowledge," August, 1913, page 308). G. P.
Merrill hasrecently compared tektites with a series of undoubted
obsidian pebbles from various localities in North and South
America and Iceland, and finds that the latter have the same
structures and peculiarities of surface-markings as the tektites.
Moreover, he shows that the chemical composition of one of
these obsidian pebbles does not sensibly differ from that of
tektites (Proceedings U. S. Nat. Mus., 1911, 481-6). Dr.
Merrill concludes that while the theory of the meteoric origin
of tektites is not controverted by these observations, it cannot
be regarded as proved until these bodies have actually been
seen to fall on to the earth's surface.
In connection with Dunn's theory of the origin of australites,
the observation by Mr. F. W. Moon of volcanic ash in Mexico,
consisting largely of perfect bubbles of volcanic glass, is of
great interest and importance (see letter in " Knowledge,"
November, 1913, page 409). It proves what Dunn was unable
to prove, that volcanic glass-bubbles are capable of being
formed and of being distributed over the earth. More inform-
ation concerning this occurrence is desirable.
METEOROLOGY.
By William Marriott, F.R.Met.Soc.
DURATION OF RAINFALL.— It is generally believed
in this country that every other day is a wet one. This
supposition is approximately correct, as the number of rain
days " in the year is about the same as the number of rainless
days. A " rain day " is held by meteorologists to be a day
on which an amount of 0-01 inch or more fell during the
twenty-four hours ending 9 a.m. of the next day. This may
be spread over the whole twenty-four hours, or it may only
occupy a few minutes in falling, but it gives no information as
to the actual duration of the rainfall. This can only be
obtained from self-recording rain-gauges, and it is satisfactory
to learn from British Rainfall that there is an increase in
the number of these instruments in use.
At Camden Square, London, where a Casella self-recording
rain-gauge has been in use since 1881, the following are the
average values for the thirty-one years, 1881-1911 : —
Rainfall. Duration. Intensity Rain days.
rate per hour.
24-13-in. 426-9 hours. -057-in. 162
In 1912 the values were : —
Rainfall. Duration. Intensity Rain days.
rate per hour.
27-88-in. 516-2 hours. -054-in. 180
The duration in 1912 exceeded the average by twenty-one
per cent., and the number of rain days eleven per cent, in
excess of the average for the same period ; the year was thus
one of very persistent rainfall, but with an intensity slightly
below the normal.
The following values from the same class of instrument
show the monthly duration of rainfall in hours at several
stations in various parts of the country during 1912 : —
Station ..
London.
Thrapston,
Northants.
Ciren-
cester.
Glos.
Hodsock,
Notts.
Southport,
Lanes.
Cray
Reservoir,
Brecon.
Height above I
sea- level /
111-ft.
262-ft.
366-ft.
56-ft.
39-ft.
1030-ft.
January...
February
March ...
April
May
June
July ...
August ...
September
October...
November
December
88-8
44-7
59-8
1-6
25-8
54-2
22-2
66-2
25-7
32-1
37-2
57-9
89-8
39-5
51-9
1-8
24-2
56-1
60-1
100-3
24-5
41-3
35-1
55-7
110-8
58-5
106-7
4-8
33-7
68-3
46-5
106-3
19-3
67-8
38-9
100-8
108-7
29-9
60-2
2-0
49-8
60-3
48-5
72-5
24-5
25-9
37-8
36-3
105-0
53-8
115-7
6-6
62-4
71-8
49-6
96-0
30-4
62-7
56-1
73-2
236-0
179-3
220-2
40-8
88-5
132-2
104-8
189-5
33-7
134-5
143-3
242-2
Year
Rainfall...
516-2
27-88
580-3
31-36
762-4
42-01
556-4
33-45
783-3
37-13
1745-0
82-83
April stands out prominently as a very dry month, the
duration of rainfall in many districts being less than two
hours. The months of greatest duration were January,
March, and August. It is interesting to notice that in the
mountainous districts, where there is a heavy rainfall, the
duration is considerably greater than at stations at a much
lower elevation.
TORNADO IN WALES.— We are accustomed to think
that tornados only occur in the United States and that nothing
of the kind is likely to be experienced in the British Isles.
On Monday, October 27th, however, a little after 5 p.m., a
most violent storm of the tornado type, accompanied by vivid
lightning and heavy rain, occurred in South Wales and passed
over the district in which Senghenydd is situated, where the
recent appalling colliery disaster occurred. From the
accounts in the local papers it appears that the storm started
on the mountain west of Treforest and rushed up the
466
KNOWLEDGE.
December, 1913.
eastern side of the Taff Valley to Cilfynydd, whence it roared
up Cwm Eldeg, and then over the north-eastern flank of
Llanfabon Mountain, and down into the Taff Valley. From
here it rushed up the western side of the valley, and expended
its fury upon the highest houses in Abercynon. It then seems
to have turned off at a tangent to Quaker's Yard and Treharris,
where its career apparently ended. The track of the tornado
was only about two hundred yards in width, but within this
area everything was devastated. Mr. Clement Edwards, M.P.,
in an appeal for monetary help for the sufferers, states that
many hundreds of houses have been ruinously damaged, and
that over two hundred families have lost beyond repair most
of their furniture and all their bedding and bedclothes and
wearing apparel. Among the more extraordinary effects of
the storm it may be mentioned that half a corrugated iron
roof was carried for several miles, through valleys, across
villages, and over mountain tops, and the tins of the sheets
detached and wound round posts as a doctor wraps a bandage
round a broken wrist. A four-ton oak tree was carried away
for nearly a quarter of a mile. Unfortunately two men lost
their lives, one being caught by the fury of the storm and
hurled a distance of one hundred and fifty yards into a field,
and the other being struck on the head by a slate.
EFFECT OF ATMOSPHERIC CONDITIONS ON
WIRELESS SIGNALS.— Dr. E. VV. Marchant read a paper
at the recent meeting of the British Association on the effect
of atmospheric conditions on the strength of wireless signals
sent out from the Eiffel Tower in Paris at 10.45 a.m. and
11.45 p.m., and received at Liverpool. The results obtained
show that there is a maximum variation from 0-6 to 1-3 in
the strength of the signals received on different days in the
same month ; the average strength of signal being assumed to
be 1-1, and that the current received on a fine clear night is
about 1 • 7 times as strong as that received in the daytime.
Although no certain relationship can yet be regarded as
established between the strength of a signal and the weather
conditions at the sending and receiving stations, so far
observation has shown that rain in Paris always corresponds
with diminution in strength of received signal. In one case,
with a wind of six meters per second velocity, blowing in a
north-west direction, the signal-strength fell to half its normal
value. The most favourable condition for signalling appears
to be a cloudy sky at both sending and receiving stations, the
signals being weaker when the sky is clear or covered with
light clouds. Rain at the receiving station appears to have a
comparatively small influence on the strength of the received
signals. The result of a set of special signals sent from the
Eiffel Tower on the evening of Saturday, July 26th, 1913 (by
the courteous arrangement of Comm. Ferri6), at intervals of
thirty minutes, between 7 and 10 p.m. (which includes the
time of sunset), shows that the increase in strength of night
signals occurs just after sunset, there being an abrupt increase
in strength of about 70 per cent. This change is quite
sudden, there being comparatively little alteration in signal-
strength until the sun has set, and no perceptible increase in
strength afterwards. There appears to be some evidence that
signals are slightly stronger just after sunset than during
normal night conditions.
MICROSCOPY.
By F.R.M.S.
DENDROMONAS VIRGARIA WEISSE.— At one of the
excursions of the Quekett Club during the autumn the above-
named organism was obtained in some quantity ; though
probably not very rare, it is certainly not frequently recorded.
Owing to its exceeding transparency and delicacy, and the
small size of the composing units, it would be easily over-
looked by anyone unacquainted with it. Saville Kent gives an
excellent representation of it from which Figure 535 is taken.*
As will be seen it is a tree-like form. The stem, called the
" zoodendrium," is rigid, dichotomous, and copiously branched.
At the end of each branch is attached a somewhat flattened
pear-shaped animalcule, the forward end obliquely truncated.
It has two flagella of unequal length, and is without a mouth,
food being taken in at all parts of the body. It has a nucleus
and one or two contractile vacuoles, and is practically a
stalked monad. The whole is perfectly transparent, and while
the individuals are extremely small — about 8m in length — the
entire organism is of considerable size, often consisting of
more than one hundred zooids, and being about 1-130" in
height. In consequence it is very difficult to observe satis-
factorily. For finding it and for a general view a half-inch
objective with good dark background illumination answers,
but for anything like a complete examination the highest
power that can be brought to bear on the object is necessary,
with a careful adjustment of light ; the use of a coloured screen
is advantageous. In the present instance, specimens were
fairly numerous on some fine grass stems which had evidently
been submerged a long time, but it was not found possible to
preserve them long under examination, as the zooids
soon became detached from the pedicle ; the stem
and branches, however, remained visible afterwards. In
most of the specimens it was noticeable that the
animalcules were arranged on a more regular level than
the illustration indicates, the mass forming, when looked at
from the side, a thin plate on the top of the beautifully
hyaline regularly-branched stem. In a surface view, at
least in the larger specimens, the pear-shaped bodies were seen
considerably compressed towards the middle of the group
owing to crowding, and were often angular in consequence.
Kent says of it : " Among all of the numerous stock-building
pedicellate varieties of the Flagellata, few, perhaps, excel the
present one in the exuberance of growth and graceful
symmetry of the erect branching zoodendrium. The
associated colonial stocks have been observed in such
abundance on the finely-divided leaves of Myriophyllum and
other water plants as to present the aspect of a perfect
forest growth of tiny crystal trees, each terminal leaflet replete
with life, and quivering with the combined vibratory action
of their flagella." Figure 535 represents an adult colony ; at
A is an isolated monad under high magnification ; and at B
a colony of two monads in process of longitudinal division,
all from Saville Kent's " Manual of the Infusoria."
JAS. BURTON.
QUEKETT MICROSCOPICAL CLUB.— October 28th,
S. C. Akehurst, " A changer for use with substage condensers."
This was on the principle of the Zeiss sliding objective
changers.
S. C. Akehurst, " A trap for free-swimming organisms."
This was exhibited in two forms and took advantage of the
phototropism exhibited by most pond animals.
James Murray, '" The Gastrotricha " : a valuable contribu-
tion dealing with this small group of minute animals, chiefly
freshwater, and of doubtful affinity. The paper describes
their form and structure, their haunts and habits, gives a
historical sketch of the group with its classification, a key to
the genera, and a list of the eighty-three species, including
one new one, which have been described, and concludes with
a lengthy annotated bibliography. The paper, with a plate of
some forty figures, appears at length in the November issue of
the Club's Journal.
E. M. Nelson on "An improved form of Cheshire's
Apertometer" and M. A. Ainslie, " A variation of Cheshire's
Apertometer " ; two papers describing improvements designed
to facilitate and render accurate determinations of the second
decimal place of N.A. with this instrument.
F.J. Cheshire did not think the form of Apertometer he had
introduced some ten years ago capable of greater accuracy
than he had then given it. He described another method of
estimating N.A. which he considered an improvement on the
older one.
PHOTOGRAPHY.
By Edgar Senior.
TESTING FOR "HYPO" IN MOUNTS, PRINTS,
AND WASHING WATER.— If silver prints are mounted
upon card that contains traces of " hypo " owing to this body
" Manual of the Infusoria." Plate XVII, Figure 1.
December, 1913.
KNOWLEDGE.
467
having been used as an " antichlor " in neutralising the
bleaching agent used in the manufacture of the paper or the
material from which it was made, its presence may bring
about fading of the print. On this account mounts for silver
prints should be selected with considerable care. There are,
however, several delicate tests that may be applied which
will detect " hypo," even when present in very small
quantity, the following being one of them. Take about three
or four square inches of the card to be tested and tear it up
into small pieces and put these to soak in a glass beaker
which is about half filled with distilled water, after which add
about half a dram of pure strong sulphuric acid and a little
pure zinc. The beaker is then to be covered with a piece of
filter paper upon which a few drops of a solution of lead
acetate have been allowed to fall. The presence of " hypo "
will be indicated by the acetate of lead becoming brown from
the formation of lead sulphide, and if after the expiration of
about half an hour there is no appearance of stains, it may be
assumed that "hypo" is absent. In any case the rapidity
with which the stains are developed will depend upon the
quantity of " hypo " present. The test depends upon the
nascent hydrogen evolved by the action of the sulphuric acid
upon the zinc, reducing the sodium thiosulphate ("hypo"),
with the formation of sulphuretted hydrogen, which combines
with the lead acetate to form lead sulphide, the reactions
being expressed by the equations
Na2S203 + 4H, + H2S04 = 2SHa + Na2SO, + 3HaO
Pb (CH3COO)2 + SH.2 = PbS + 2 (CH3COOH)
The presence of " hypo " in prints may readily be detected in
a number of ways, the iodide of starch test being commonly
employed for the purpose, the solution being made up in
the following manner. A small piece of starch is taken and
boiled in about three drams of distilled water until a clear
solution is obtained, to which when cold about a dram of iodine
dissolved in alcohol is added: this causes a dark-blue coloured
solution to be produced due to the formation of iodide of
starch. " The addition of iodine dissolved in water by the aid
of potassium iodide will answer instead of iodine in alcohol."
To apply this test to ascertain whether " hypo " is present in a
print, small pieces of the latter are boiled in a test tube
containing some distilled water ; the solution is then allowed
to get quite cold when one or two drops of the iodide of
starch are added to it, and should the blue colour be
discharged the presence of "hypo" is indicated, but should
the blue colour remain it may be assumed that this salt is
absent. The presence of " hypo " in the washing water of prints
is readily shown by taking two test tubes and filling one with
pure distilled water and the other with the water to be tested,
and if a drop or two of the iodide of starch solution be added
to each, sufficient to give a faint blue colour to one when
viewed by looking through it at white paper, a total absence
of any colour in the other will show that " hypo " is present
in it. The presence of " hypo " is also easily shown by means
of an alkaline solution of potassium permanganate, for which
purpose the following formula by Professor Bottcher is to be
recommended : —
Potassium permanganate (pure) ... l£ grains
Caustic soda ... 15£ ,,
Water (distilled) 18i ounces
When using this solution the presence of " hypo " is shown
by the pink colour changing to a green, owing to the
reduction of the manganese salts. The washing should
therefore be continued until a small quantity of the water
contained in a test tube will allow of some of the pink
solution being added to it without its becoming green.
PHYSICS.
By Alfred C. Egerton, B.Sc.
SPARK PHOTOGRAPHS AT HIGH PRESSURES.—
The curious phenomena which attend the passage of
electricity through gases are manifold ; the nature of the effect
is chiefly dependent on the pressure. At ordinary pressures
the usual spark discharge is obtained ; as the pressure
increases, so it becomes more and more difficult for the spark
to pass : the length of the air gap must be decreased, and
when the discharge passes a fatter spark is obtained and a
larger current is carried across the gap. At low pressures,
the discharge passes more readily until a certain lower
limit of pressure is reached, when the discharge passes again
with great difficulty. The discharge first appears as an
elongated spark; then as a straight but rather fuzzy strip; then
it fills the whole space between the two electrodes, and then
appears the Faraday dark space near the negative electrode,
which is surrounded by a luminous glow ; then, again, behind
this appears the Crookes dark space, where the negative
electrons are ejected normally to the surface of the electrode.
As this space begins to show, so the discharge usually breaks
up into a series of light and dark bands. Finally the Crookes
space fills the whole tube, and if exhaustion is carried very
much further the space refuses to carry any discharge of
electricity.
The study of these phenomena has led to the wonderful
developments of physical science during the last twenty years.
The positive, the negative or kathode, and the X-rays and
the rays they in turn give rise to — secondary rays — were all
discovered during investigations to explain these electric
discharges ; indeed, much light has been thrown on the
nature of matter and its relation to electricity by such
work done mainly by Sir J. J. Thomson and those who
have been inspired by his genius. An atom of matter is
built up of negative charges of electricity, some free to
move as they will, others bound, some controlling the
chemical properties of the atom, others resident within
and taking no part in chemical actions. These negative
charges are held together by the rest of the atom which is
positively charged. Whether this charge is concentrated in a
central nucleus or whether it is distributed throughout the
mass of the atom is still an open question ; the positive
portion is associated with the chief portion of the mass of the
atom. The effects obtained in the electric discharge in gases
are mainly due to the action of charged particles (electrons) or
positively charged atoms on the molecules of gas in their
path. If the velocity of the charged particle is sufficient it
will " ionise " the molecule on collision with it ; that is to say,
it will split it into oppositely charged parts. The current is
carried at the lower pressures by these moving ions.
The explanation of the discharge through gases at high and
ordinary pressures is dependent on similar considerations. A
discharge will pass through some gases more readily than
others ; through neon the discharge passes most readily. In
most cases of the conveyance of electricity through gases the
ions have to be produced by some kind of rays, but in the
spark discharge there are many more ions produced in a given
time in the neighbourhood of the electrodes than recombine in
the same time, and the discharge, as it were, "supports itself."
The differences in the ease with which the discharge will pass
through the gas depend on the amount of energy required to
ionise the molecules of the gas. Investigations on these matters
have been most ably carried out 'by Professor Townsend, of
Oxford.
Amongst the mass of literature on these subjects we may
note a paper read before the Rbntgen Society in April, 1913,
by Professor A. W. Porter. The terminals of an induction
coil are connected to two electrodes, one on either side of a
photographic plate. The photographic plate is situated in a
dark chamber, in which the pressure may be raised up to ten
atmospheres. When the negative electrode is against the
sensitive side of the plate, at ordinary pressures, fanlike
impressions of the discharge are obtained on developing the
plate; but on raising the pressure the fanlike expansions
separate into two filaments. The negative discharge gives
figures with lines of discharge which are characteristic of the
positive spark lines for the same gas ; that is, a positive re-
bound must occur after the negative discharge has taken place.
The distinction between the negative and positive dis-
charges is very marked, but they are somewhat more
similar at higher pressures. The fanlike discharges are shown
to be due to the presence of nitrogen. The spark in oxygen
468
KNOWLEDGE.
December, 1913.
passes easily and the effects at higher pressures obtained with
air are due to the presence of oxygen, the negative discharge
in nitrogen being very difficult to obtain at high pressures.
In hydrogen (he discharge merely amounts to a glow round
the terminal. The positive discharges, when the positive
electrode is put against the sensitive side of the plate, are not
so distinctly different in different gases, and they merely
become finer at higher pressures. These experiments will
help to define many curious effects obtained in the brush and
spark discharge, but there is much which remains to be
cleared up. The actual condition of affairs at the negative
electrode is, perhaps, one of the most interesting points upon
which the above researches may throw some light.
ZOOLOGY.
By Professor J. Arthur Thomson, M.A., LL.D.
COMMENSAL CRUSTACEANS IN CHAETOPTERUS
TUBES. — Professor A. S. Pearse has studied three
Crustaceans — Polyonyx macrocheles, Pinnixa chaeto-
pterana, and Pinnotheres maculatus — which occur as com-
mensals in the tubes of Chaetopterus variopedatus at
Wood's Hole. The two first-named are not closely related,
Polyonyx being a Galatheid and Pinnixa a true crab of
the family of Pinnotherids, but they have many similarities.
Like most Crustaceans, they are strongly thigmotropic, and
creep into crevices or tubes, which would easily account for
their taking up their abode with Chaetopterus. They are
rarely found elsewhere. They become quiet when a shadow
passes over them, which has probably protective value. They
feed by " net casting," after the manner of barnacles, and this
is admirably suited for the capture of food within the tubes.
The " nets " in both are formed by the inner blades (or
endopodites) of the third maxillipede, which are well supplied
with plumose setae and are swept through the water. Both
forms have the last leg shortened. Both have a long breeding
season, producing one brood after another, and this is perhaps
fostered by the sheltered life. They gain from their
association with the worm, but the worm's view of the
situation is unknown.
REMARKABLE BLIND CEPHALOPODS.— One of the
most precious spoils of the Michael Sars North Atlantic Deep
Sea Expedition of 1910 (carried out under the auspices of the
Norwegian Government and the superintendence of Sir John
Murray and Dr. Johan Hjort) was a blind cuttlefish, Cirro-
thauma murrayi n. g. et sp. apparently adapted for deep sea
life. Three thousand metres of wire were out when it was
captured. The specimen is perfectly gelatinous and semi-
transparent. Its fragility recalls that of a Ctenophore. A
delicate web unites the arms. The nerves can be seen
shining through the whole length of the arms. The gelatinous
body exhibits an exceedingly faint violet colour, and only the
parts round the mouth, the proximal portions of the arms,
and the web exhibit the purple chocolate colour peculiar to
many deep-sea animals. Chromatophores are absent, except
a rhombic one between the two fins. Very peculiar minute
suckers (thirty-six in number) poised on long spindle-shaped
and clumsy stalks of gelatinous substance occur on the inner
side of the arms. They are evidently out of function, being
flattened and without a sucking pit, and smaller than the normal
proximal suckers. In each stalk there is a curious structure
which may be a luminescent organ and reflector. The eye is
minute, without a lens, with a very degenerate retina and
optic nerve. There are deep-sea cuttlefishes with small eyes,
but no case save this one is known where the structure of the
eye is involved. Its degeneration has gone further than in
many blind vertebrates.
PHOSPHORESCENCE OF PEN NATU LIDS.— Professor
W. A. Herdman has recently described the "phosphorescence"
of Funiculina quadrani<ularis,the\a.rgest British Pennatulid.
The light on the bare part of the colony was more intense
that that produced by the polyps. " The long bare lower
part of the stem, nine inches to a foot in length, when gently
stroked in the dark glows with a continuous sheet of light
of (it seems to me) a pale green colour which flickers or
pulsates like a lambent flame." In Pennatula phosphorea
the luminosity seems to be confined to the polyps. It is
more general and more lasting than the sparkles that the
polyps give in Funiculina. In the report on the spoils of
the Michael Sars Expedition, the artist has given a figure of
the luminescence of Umbellula giintheri which was still
brilliantly phosphorescent although drawn up from the
immense depth of more than five thousand metres. Dr.
Hjalmar Broch refers to Sir Wyville Thomson's note that
the spectrum of Pennatulid phosphorescence is very restricted
and sharply included between b and D. Niedermeyer found
that the phosphorescence of Pteroeides griseum was
restricted to the polyps and small zooids, and is temporarily
lost after exposure to sunshine, which probably destroys, for
the time being, the product of some intracellular secretion.
Although its phosphorescence is only seen by us when we
stimulate these Pennatulids, Broch suggests that deep-sea
forms may show it without irritation.
NOTICES.
CHANGE OF ADDRESS.— We are asked to announce
that Messrs. Haseltine, Lake & Company, Patent Agents,
have removed from 7 and 8, to No. 28, Southampton Build-
ings, Chancery Lane, E.G.
OPTICAL LANTERNS.— Messrs. Newton & Company's
new catalogue is noteworthy for the many types of science
lanterns listed, and is particularly valuable on account of the
variety of arc lamps and other projection illuminants therein
described.
SCIENTIFIC BOOKS.— We have received from Mr. H. K.
Lewis his quarterly list of new books added to the circulating
library. It contains the books published from July to Sep-
tember. Under the heading, " Technology," we notice that
the first volume of the new edition of Lewkowitsch's
"Chemical Technology and Analysis of Oils, Fats, and
Waxes " is included.
THE "WELLCOME" PHOTOGRAPHIC RECORD
AND DIARY, 1914.— This useful little pocket guide to
photography has been reissued by Messrs. Burroughs,
Wellcome & Company. Particular attention is given in
this edition to blue and green toning and the production of
various colours by development. It should find a place in
every photographer's library.
SCIENTIFIC, INDUSTRIAL AND TECHNICAL
BOOKS. — Messrs. Crosby, Lockwood & Son have published
a new illustrated catalogue of books coming under the above
heading, and we are asked to announce that they will be
willing to send a copy post free to all who may be in any way
interested.
SECOND-HAND MICROSCOPES.— Messrs. H. F. Angus
and Company have issued their fourth catalogue under this
title. A good selection of instruments, objectives, and
accessories, as well as general optical and physical apparatus,
will be found therein.
NATURAL HISTORY BOOKS.— In Messrs. John
Wheldon & Company's latest catalogue will be found,
besides general literature, a list of important remainders of
books on Natural History, and many sets of scientific
journals, both English and foreign.
THE SCIENTIST'S REFERENCE BOOK AND
DIARY, 1914. — Once again we have pleasure in noting the
appearance of this handy pocket book. In addition to a diary
and space for memoranda it contains tables useful for
everyday reference and a short account of the progress of
science in 1913. It is published by Messrs. James Woolley,
Sons & Company, Limited, of Manchester.
Knowledge
v. 36
Physical &
Applied Sci.
Serials
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