f ^ ^ \ Si \ 30'^- 137a. NATURE A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE VOLUME XVII. NOVEMBER 1877 to APRIL 1878 " To the solid ground Of Nature trusts the mind which builds -^or aye'' — Wordsworth MA CM ILL AN AND CO. 1878 V- - '>, t ( Ml top, V LONDON E. CLAY. SONS, AND TAYLOR, rRINTERS, BREAD STREET HILL, QUKEN VICTORIA STREET the Radiometer and its Lessons, 26, 61 ; Mr. Crookes and Eva Fay, 81, loi, 122 Carpmael (W.), Telephone Experiments, 342 Cartilage, Transformation of, into Bone, 345 Caspian, Prof. Grimm on the Fauna of the, 345 Cassell's Natural History, Vol. i , 365 Castleton, Local Museum at, 454 Castor, the Binary Star, 105 Caucasus, Prof. Abich's Work on the, 309 Causation of Sleep, 124 Cavendish (Henry), his Writings on Electricity, 75 Cazin (Prof.), Death of, 16 Cecil (Henry), Hearing and Smell in Insects, 102, 381 ; the Wasp and tlie Spider, 448 "Celestial Atlas," Dien's, 141 Cerf (Mdlle, Henrietta), Death of, 71 Cesnola (Gen. L. Palma di), "Cyprus," 397 Chadwick Museum, 272 Challens;er, the. Estimates of the Volume of the Gulf Stream, T. Mellard Reade, 144 ; in the Atlantic, Sir Wyville Thomson's Account of, 145, 185 ; Laboratory Experiences on the, 394 Channel Islands, a Zoological Station for the, W. Saville Kent, 102, 475 Chappell (Wm., F.S.A.), Music a Science of Numbers, 32 Charkow, University of, 195 Charnwood Forest, the Rocks of, 294 Cheeseman (T. F.), Fertilisation of Glossostigma, 163 Cheijan (Omer), Translation of the Poems of, 351 Chemistry : Chemical Society, 40, 75, 134, 215, 255, 315, 394, 439, 499, 519; the Research Fund, 291, 309, 454; Anniver- sary Meeting of the Society, 479 ; a Problem in Chemical Affinity, 151; Chemical Notes, 150, 269; Die chemische Industrie, 251 ; Fowne's Manual of, 24; Prof. Kekule on the Position of, 55 ; N. N. Lubavin on Physical Chemistry, 240 ; Institute of, 291, 309 ; Chemistry and Algebra, Prof. J. J. Sylvester, F.R.S., 284, 309; Frankland's Researches in, Prof. J. Emerson Reynolds, 318; Dictionaries of, 455, 514 Chester Society of Natural Sciences, 16 Chili: Insect-Fauna of, R. McLachlan, F.R.S., 162; A. R. Wallace, 182 j the Insects of Chili and New Zealand, 221, 260 Chimpanzee at the Westminster Aquarium, 153 China: Telegraphy in, 310; Exploration of, 346; the Tele- phone in, 392 ; Mr. Baber's Report of the Grosvenor Mission, 434 ; Geographical Notes, 452 ; Chinese Remedy for Cynanche tonsillaris, 475; "Gray's China," 484; Chinese Plants and Animals in Paris, 513 Chloride of Silver Battery, Dr. De la Rue's Researches on the Electric Discharge with, 214 Chronometers, Trial of German and Swiss, 409 Cinchona, Cultivation of, 410 Cissbury : Exploration of the Cave-Pits, 53, 171, 215, 409 Clark (Xenos), Singing in the Ears, 342 Cleopatra's Needle, 251 Cliff-Dwellers in the United States, 409 Climatology : of the Spanish Peninsula, 248 ; of the Fiji Islands, 248 ; of India, 307 ; of English Sea-side Resorts, 356 Clock, a Watchman-Controlling, 292 Clusters and Nebulae, Literature of the, 288 Cobalt and Nickel, lodates of, 150 Cochin China, the French Colony in, 492 Coggia's Comet, 497 Cohesion Figures in Liquids, Diffusion of, 124 Cole (Alan S. ), State Aid to Music, 474 "Coleoptera Sanctas-Helense," Wollaston's, 338 Colley (Prof. R.), Electrical Experiment, 282 Collieries, Telegraphic Warnings in, 16 Colonies, Exploring, 290 Colorado, Atlas of, 371 Colours, Comparison of the Intensity of Light of Various, 438 Colour Sense of the Greeks, Prof. W. Robertson Smith, 100 Columbus, the Burial-place of, 17 Comets : De Vico's, 15 ; of Short Period of 1878, 36; of 1873, 46 ; the Comet of 1672, 63 ; the Austrian Comet-Medal, 129 ; Donati's Comet of 1858, 149; the Comet 1106, 189; the Comets of 1618, 247; the Periodical Comet 1873, 344- Tempel's Comet of Short Period, 408 ; Coggia's Comet, 497 '. Encke's Comet in 1878, 507 * Compass Adjustment in Iron Ships, Sir William Thomson, F.R.S., 331, 352, 387 Compasses, the Geometry of, Oliver Byrne, 199 Congo, the Yallala Rapids on the, 62 Connaissance des Temps for 1879, 70 Conrad (Timothy Abbott), Death of, 39 Conservation of Energy, Lecture Experiment, W. A. Shen- stone, 45 Cooke (C. J.), Landslips near Cork, 425 Cooke (Conrad W.) Cumulative Temperatures, 322, 448, 486 Cooling Powers of Various Liquids, 132 Cooper (Robt.) Mr. Crookes and Eva Fay, 183 Copeland (Ralph), Meteor, 29 Corbett (Dr. Joseph Henry), Death of, 410 Cordoba Observatory, 83, 209 Corfield (Dr. W. H.), Elements of Articulate Speech, 447 Cork, Landslip near, C. J. Cooke, 425 Corpse, Spasms in a Guillotined, 437 Corsica, Exportation of Blackbirds from, 309 Coryphodon, Brain of a Fossil Species of, 222 "Cotton Goods, the Sizing of," Thomson, 4 Cotton (Dr. R. P.), his Collection of Ilford Fossils, 231 Crabs, Horse- Shoe, 289 Craig- Christie (A.), the Future of our British Flora, 62 Crawfish, Artificial Culture of, 133 Cremmen, Discovery of a Prehistoric Burial Ground near, 391 CroU (Dr. James, F.R.S.), Age of the Sun in Relation to Evolution, 206, 321, 464 Crookes (William, F.R.S.), the Radiometer and its Lessons, 7, 43; and Eva Fay, 81, lOi, 122, 183, 200 Cruelty to Animals' Act and Physiological Teaching, Frank W. Young, 45 Crustaceans, Classification of Decapod, 127 Cryptogams, Hofmeister's work on, 344 ; Cryptogamic Society of Scotland, 133; Cryptogamic Society of Italy, 491 Cumberland Association of Literature and Science, 133 Cumulative Temperatures, 308, 322, 448, 486 Curious Phenomenon, 10 Cyanide of Gold, Double Salts with, 151 Cycadese, Structure of, 222 Cyclones and Anti- Cyclones, 134 Cynanche tonsillaris, Chinese Remedy for, 475 " Cyprus," General L. Palma di Cesnola, 397 D'Albertis' and Beccari's Voyage Round the World, 53 D'Albertis' Exploration of New Guinea, 383 Danish Greenland, Dr. Henry Rink, 57 D'Anvers (N.), " History of North African Discovery," 280 Danube, the, and the Aach, 233 D' Arrest's Spectroscopical Researches, 311 Darwin (Charles, F.R.S.), Conferring an Honorary Degree on at Cambridge, 52, 64 ; Fritz Muller on Flowers and Insects, 78; Proposed Memorial to, 95, 350; "Different Forms of Flowers," 445 Darwin (Francis), Insectivorous Plants, 222 ; Analogies of Plant and Animal Life, 388, 411 Darwin (G. H.), Geological Time, 509 Davids (T. W. Rhys), Buddhism, 239 Davyum, Sergius Kern, 245, 292 Dawson (G. M.), Drowned by a Devil Fish, 282 Deaf and Dumb Language, 479 _ Decapod Crustaceans, Classification of, 127 Declination Ranges and Sun-spots, Prof. Balfour Stewart, F.R.S., 326 Deep-Sea Ascidians, 289 Deer, Prof. Boyd Dawkins on the, of the Miocene and Pliocene Strata, 255 De la Rue's Diaries and Calendars, 1 1 De la Rue (Warren, F.R.S.), Researches on the Electric Dis- charge with the Chloride of Silver Battery, 214 Dendritic Gold, 283 Denning (W. F.), Meteor of October 19, 1877, 10; Shooting Stars, 201 Density and Sound, J. Cameron, 507 Development in Plants, the First Stages of, 433 ' VI I:\IDEX [Nature, May 30, 1878 De Vico's Comet of Short Period, 15 Devil Fish, Drowned by a, 27, 282 Dieii's "Celestial Atlas," 141 Diet, A Physician's Experiment, 305 *Diffasion Figures in Liquids, 87, 102, 124 Diffusion of Gases, 92 Digital Reduction, the Laws of, 128 Digits, Hereditary Case of Six, 372 Dimetian and Pebidian Rocks of Pembrokeshire, 155 Dispersal, Means of, W. L. Distant, 124 Distant (W. L.), Means of Dispersal, 124; Oriental Affinities in the Ett>iopian Insect Fauna, 282 Distillation of Organic Liquids by Means of Steam, 270 Dixon (Charles), Towering of Wounded Birds, 45 Doberck (Dr. W.), Ole Romer, 105 Dog-Fish, Capture of a, 251 Dohrn (Dr. Anton), the Zoological Station, Naples, 329, 360 Donati's Comet of 1858, 149 Donisthorpe (Wordsworth), Change of Habits in Toads, 242 Dorpat, University Intelligence, 354 Dorset, Earthquake in, 38 Double Salts with Cyanide of Gold, 151 Double Stars, 407 Dowdeswell (G. F), Bacteria in Water, 323 Downing (A. W.), Sun-spots and Terrestrial Magnetism, 242 Draper (Dr. Henry), Oxygen in the Sun, 339 Dresden, the Polytechnic, 354 Drosera rotundifolia, the Nutrition of, 222 Drought in the Southern Hemisphere, 436, 447, 454 Drury's "Chronology at a Glance," 253 Dublin, the Royal Society, 46 Dumas' Lectures on Chemical Philosophy, 193 Duncan (Dr. P. Martin), Cassell's Natural History, 365 Dundee Naturalists' Society, 54 Dun Echt Observatory Publications, 432 Dust, Explosive, 283 Dwarfs, African, 364 Dyer (Prof. W. T. Thiselton), the Rain- Tree of Moyobamba, 349 Early Man, Traces of, in Japan, 89 Ears, Singing in the, Xenos Clark, 342 Earth, Age of the, W. M, Flinders Petrie, 465 Earthquakes, 330 ; at Lisbon, 1 7 ; in Dorset, 38 ; New York, 38 ; at Iquique, 90; in Canada, 90, 1 10; in Nebraska, no; the " Ionia Volcano," iio; at Beachburg, 212; in Jersey, 272; of January 28, 1878, 292 ; at Liesthal, 475 ; at St. Stefano, 514 Earthquakes and Seiches, Dr. F. A. Forel, 281 Earthworm in Relation to the Fertility of the Ground, 18, 28, 62 Earthworm, Supposed Gigantic, 325 Earwigs, 128 Easter, the Date of, 433 Eastern Excavations, 397 Eclipse Photography, the Use of the Reflection Grating in, J. Norman Lockyer, F.R.S., 354 Eclipses : Solar of February 2, 1878, 36 ; Total Solar Eclipse of A.D. 418, 163; the Total Solar Eclipse of July 29, 1878, 250, 269, 381, 452, 453 ; the Coming Total Solar Eclipse,* J. Norman Lockyer, F.R.S., 481, 501 Eden (C. H.), "The Fifth Continent with the Adjacent Islands," 121 Edinburgh: University Buildings Extension Scheme, 95, 114; University Intelligence, 154, 294, 517; University Statistics, 214; Royal Society, 216, 276, 439, 480; University Chemi- cal Society, 296, 500, 526 ; New School of Medicine at, 354 ; Proposed Portrait of Dr. Balfour, 393 Edison's Phonograph, 90, 190, 291, 469 Educational Travel, 324 Education, Female, in Germany, 478 Education in France, 1 70 Education, Technical, Prof. Huxley on, 97 Edwards (M. Milne), appointed President of the French Scien- tific Association, 152 Eggs, the Earliest Changes in Animal, 509 Egypt, Flint Flakes, &c., from, 215 Eidum, a Submerged Village, 232 Eimer (Prof.), on the Nervous Systen^ of Medusa-, Geo. J. Romanes, 200 Elasmobranchs, the Fins of, Prof. St. G. Mivart, F.R.S., 355 Electrical Analogies with Natural Phenomena, 226, 385 ; Elec- trical Experiments, 180, 282 Electrical Nerves, Social, 305, 346 Electric Battery, a New, 455 Electric Lighting, 156, 310, 437 Electricity, Gas Lighting by, 495 ; and Light, Experiment on, 233; and Railway Collisions, 371 ; and Railway Working, W. E. Langdon, 461 Electro-Generator, Electromotive Force of, 514 Electro -Magnets, 20, 40, 56, 76, 96 r Electrometer, New Form of Absolute, 115 Electromotive Force, 252 Electrostriction, Prof. Mills, F.R.S., on, 235 Elliot (James), a Meteor, 425 Ellis (Alex. J., F.R.S.), Appunn and Koenig — Beats in Con- fined Air, 26 ; the Phonograph, 4, 85 Elton (Capt.), Death of, 383 Encke's Comet in 1878, 507 English Lake-Dwellings and Pile Structures, Prof. T. Rupert Jones, F.R.S., 424 Entomology : Entomological Society, 75, 176, 256, 395, 459 ; Entomology in America, 229 ; Entomological Exhibition at the Westminster Aquarium, 351, 391, 402 ; Entomological Queries, 467 Eocene Flora of Bournemouth, J. S. Gardner, 47 Erlangen, University Statistics, 214 Esquimaux in Paris, 54, 309 Ethiopian Insect Fauna, Oriental Affinities in the, W. L. Distant, 282 Ethnography, Lectures on, in Paris, 330 Ethnological Literature of 1876, 133 Ethnology of North America, 53 Ethylen Oxide, New Modes of Forming, 150 Eucalyptus : Prince Pierre Troubitzkoy, 10 ; Arthur Nicols, loi, 342; used for Checking Fire, 38; Dr. Calmy, 283; as Fuel, 392 ; the Uses of, 514 Euplectella Sponge?, 222 Euphrosyne, the Minor Planet, 36 Eurydice, the Meteorological Conditions Affecting the Wreck of the, 437, 466 Eva, the Minor Planet, 210 Everett (A. H.), Volcanic Phenomena in Borneo, 200 Everett (Prof. J. D.), " Shorthand for General Use," 17 ; Undei-- ground Temperature, 476 Evolution, Age of the Sun in Relation to, J. I. Plummer, 303, 360 ; Dr. James Croll, F.R.S., 321, 464 Evolution of Heat during Muscular Action, Prof. A. Fick, 285 Exner (Prof.), on the Diffusion of Gases, 92 Exploring Colonies, 290 Explosions in Mines, W. Galloway, 21 Explosions, A. Mackennah, 123 Explosive, Discovery of a New, 436 Explosive Dust, 283 Eyck (Jan van), Colossal Bronze Statue of, 490 Eye-brows, Supplementary, W. Ainslie Hollis, 124 Eye-motions during Sleep, &c., 371 Falb (Dr. Rud)., his Travels in South America, 513 Faraday (Prof.), Bust of, 291 Faraday's "Experimental Researches," Sylvanus P. Thompson, 304, 361 ; Bernard Quaritch, 342 Faunas and Floras, the Comparative Richness of, tested Numeri- cally, Alfred R. Wallace, 100 Fay (Eva), Mr, Crookes and Dr. W. B. Carpenter, F.R.S., 81, 122 ; Alfred R. Wallace, loi Faye (A. E. A.), elected Minister of Instruction for France, 91 Female Education in Germany, 478 Ferment in Plants, 455 Ferns and Mosses, Hofmeister's work on, 344 Ferns, J. Smith's British and Foreign, 43 Fertilisation in Thyme and Marjoram, 127 Fertilisation of Glossostignia, J. F. Chesseman, 163 Fertilisation of Plants, 221 Fetichism in Animals, Geo. J. Romanes, 168; C. G. O'Brian, 402 Fick (Prof. A.), on the Evolution of Heat During Muscular Action, 285 Fielden (Capt.), on the Geology of the Arctic Regions, 473 Field-mice, or Rats, Plague of, in Smyrna, 437 Nature, May 30, 1878] INDEX Vll " Fifth Continent and the Adjacent Islands," C. II. Eden, 121 I'Mguier's " Les Six Parties du Monde," 17 Fiji Islands, the Climatology of the, 248 Films, Experiments on Fluid, 44, 6l "Fire-Ball," Fall of a, 10 Fire-damp, Commission on Explosions from, 252 Fires, Telegraphic Warnings of, in Paris, 91 P'isheries, of the Rhine, 212; the American Inland, 382 Fishes the Distribution of Freshwater, 128 ; Prof, E. Perceval Wright on Fishes' Tails, 286 ; Glacial and Post-glacial Fishes of Norway, 509 Fittig's "Organic Chemistry," French Translation of, 233 Fitzgerald (Geo. Fras.), the Radiometer and its Lessons, 199 Flame, Vibrations of a. Experiments on, 54 Flame Spectra, Observing the Coloured Lines of, 273 Flames, Temperature of, 269 Flammarion (M.) on Stellar Systems, 82 Floating Magnets, Alfred M. Mayer, 487 Flora, British, the Future of Our, A. Craig-Christie, 62 "Flora of Tropical Africa," Prof. D. Oliver, F.R.S., 319 Floras and Faunas, the Comparative Richness of. Tested Numerically, Alfred R. Wallace, loo Flower (James), Death of, 37 Flower (Prof., F.R.S.), Ilunterian Lectures, 350 Flowers, Darwin's Different F'orms of, 445 Flowers and Bees, John B. Bridgman, 102 Flowers and Insects, 1 1 ; Fritz Midler on, 78 Fog-Signals, Dr. Tyndall, F.R.S., 456 Forbes (Henry O.), Selective Discrimination of Insects, 62 Forbes (Prof. Geo.), the Telephone as an Instrument of Precision, 343 Forel (Dr. F. A.), Seiches and Earthquakes, 281 Forests, the Air of, 515 Forficulida; (Earwigs), 128 Fossils: Discovery of Fossil Plants in Grinnell Land, 115; Fossil Fungus, 127 ; the Brain of a Fossil Mammal, 222, 340 ; Preparing Fossils, 369 ; Fossil Hunting at Bournemouth, J. S. Gardner, 369 ; London Clay Fossils, 487 ; Fossil Insects, 508 Foster (Prof. G. Carey, F.R.S.), the Radiometer and its Lessons, 5, 43, 80, 142 Foucault's Pendulum Experiments, 108 Fownes' " Manual of Chemistry," 24, 46 Fox (Gen. A. Lane, F.R.S.), the Arrangement of Museums, 484 France : French Geographical Society, 1 7 ; Association Poly- technique, 54 ; Statistics of Suicides in, 54 ; Bequest to the French Institute, 70 ; Universities in, 1 14 ; French Acclima- tisation Society, 132; Education in, 193, 214; the Scientific Association of, 232, 271 ; French Association for the Ad- vancement of Science, 251, 350 ; French Academy of Sciences, 273; Distribution of Prizes, 271 ; Proposed Exploring Expe- ditions, 329 ; Agricultural Weather Warnings, 371 ; Statistics of Wine Production, 372 ; Preservation of Boulders in, 391 ; Drought in the South of, 475 ; Societes Savantes, 490. See also Paris, &c. Frankland's Researches in Chemistry, Prof. J. Emerson Reynolds, 218, 318 Freiburg, University Statistics, 334 French Guayana, 508 French Popular Science, 120 Freshwater Fishes, the Distribution of, 128 Fries (EHas Magnus), Death of, 329 ; Obituary Notice of, 343 Fruit, Fungoid Disease of, 91 Fruits, the Action of Certain Antiseptic Vapours on the Ripen- ing of, 150 Fungoid Disease of Fruit, 91 Fungus, a Fossil, 127 Gabb (W. M.), Sense in Insects — Drowned by a Devil Fish, 282 Gabriel (M. Delafosse), Illness of, 370 Galileo, was. Tortured ? Sedley Taylor, 299 Galloway (W.), Explosions in Mines, 21 Gannister Beds of Northumberland, Marine Fossils in the, Prof. G. A. Lebour, 320, 352 "Gardener Bird," the, no Gardner (J. S.), the Eocene Flora of Bournemouth, 47 ; Fossil Hunting at Bournemouth, 369 Garnett (William), Leidenfrost's Phenomena, 466 Gas- Holder, New Form of, Prof. W. F, Barrett, 253 Gas -Lighting by Electricity, 495 Gases : Diffusion of, 92 ; the Liquefaction of the, 117, 265 ; the Last of the, 177; Experiments on Spread of, through Bodies, 393 Geikie(Prof. A., F.R.S.), Prof. Bryce's Ararat, 205 ; American Geological Surveys, 431 ; the Old Red Sandstone of Western Europe, 471 Gems from Russia, 72; the Production of Artificial, 55, 136, 152 Geneva, Lake of. Earthquake near, 234 Geneva Society of Physics and Natural History, 136 Gentiana asdepiadea and Bees, F. M. Burton, 201 Geography : Geographical Notes, 249, 270, 290, 308, 324, 364, 383, 408, 434, 452, 467, 489, 508; Geography at French Railway Stations, no; Geographical Magazine, 132, 293, 468 ; Geographical Bibliography, 324 Geology : Geological Congress, International, 65 ; Hauer's " Die Geologie," 78; Geological Society, 115, 136, 155,255, 294, 335. 374, 395, 518; Geological Work of the United States Survey under Dr. Hayden during the Summer of 1877, 129 ; Geological Surveys of America — Missouri, Prof. A. Geikie, F.R.S., 431 ; Geologists' Association, 475; Geologi- cal Time, G. H. Darwin, 509 Geometrical Teaching, the Association for the Improvement of, 89, 251 "Geometry of Compasses," Oliver Byrne, 199 Geometry of Three Dimensions, Theorems Relating to. Prof. S. Newcomb, F.R.S., 240 Germany: German Universities, Statistics of, 103; German Chemical Society, 131, 273; Botany in, 158; German Scien- tific Association, Report of the Munich Session, 350 ; Uni- versity Libraries of, 374; German Polytechnic Congress, 394; German Alpine Club, 468 Ghinozzi (Dr. Carlo), Death of, 170 Gibraltar, the Geology of, Prof. A. C. Ramsay, F.R.S., and James Geikie, F.R.S., 518 Giessen, the Ph. Degree at, 75 ; University Statistics, 478 Gilchrist Educational Trust, 334 Gillmore (Parker), " The Great Thirst Land," 360 Ginez (Francisco), Carnivorous Plants, 63 Giraud (Dr. H.), Death of, 513 Glacial Geology of Orkney and Shetland, S. Laing, M.P., 123 ; Prof. M. Forster Heddle, 182 Glass for Reflectors, Henry Bessemer, 241 Glass, the Engraving of, 372 ; Compressed Hard, 392 Glassy Sponges, 222 Glossostigma, Fertilisation of, T. F. Cheescman, 163 Goethe, Proposed Monument to, 211 Gold, Dendritic, 283 Gold in Teheran, 115; in Ne«r Guinea, 408 Goode (G. Brown), the Bermuda Lizard, 425 Gordon (J. E. II.), the Telephone as a Means of Measuring the Speed of High Brakes, 424 Gore (G., LL.D., F.R.S.), the Thermo-Electric Properties of Liquids, 479 Gorilla, Dissection of the Berlin, 89 Gottland, Discovery of Ancient Bronze Weights in, 351 Gottingen, Royal Academy of Sciences, 156, 296, 480; Uni- versity Statistics, 214 Government Research Fund, 403 Grapes, Frost-Bitten, 132 " Gray's China," 484 Great Pyramid, J. G. Jackson, 243 "Great Thirst Land," Parker Gillmore's, 360 Greek Cities and Islands of Asia Minor, W. S. W. Vaux, 119 Greeks, the Colour Sense of the, Prof. W. Robertson Smith, 100 Green Algte, 289 Greenland, Danish, Dr. Henry Rink, 57 Greifswald, University Statistics, 354 Greyhounds, Turkoman, 434 Grimm (Prof.), on the Fauna of the Caspian, 345 Grinnell Land, Fossil Plants found in, 115 Groshans (Dr. J. A.), Photography Foreshadowed, 202 Grove's Gas Battery, 394 Grove's Dictionary of Music, Dr. W. H. Stone, 422 Guadaloupe Island, the Birds of, 128 Guildhall, Public Standards at the, 454 Guillemard (Arthur G.), Great Waterfalls, 221, 242 Gulf Stream, the Challenger Estimates of the Volume of the, T. Mellard Reade, 144 vni INDEX {Nature, May 30, 1878 Giinther (Dr., F.R.S.). Gigantic Land Tortoises, 483 Hailstones, Rain-drops, and Snow-flakes, the Formation of, Prof. Osborne Reynolds, F.R.S., 207 Hailstorm at Brisbane, 455 Hair, Human, the Colouring Matter of, 355 Halle, University Intelligence, 235, 478 Haller (Albert von), 90, 223 Halogen Derivatives of Amines, 151 Handwriting, Restoration of the, of Old MSS., 351 Hanover, the Polytechnic at, 335 Harmonograph, 394 Harrison (Park), Exploration of the "Cave Pit," Cissbury, 53 Harrison (W. H,), " Lazy Lays," 38 Harrison (W. J.), Geology of Leicestershire and Rutland, 58 Harrow School Bathing-Place, Arthur G. Watson, 487 Hartlaub's " Birds of Madagascar," Prof. A. Newton, F.R.S., 9 Harvard College, U.S., Observatory, 363 Harvey (William), Notice of, by Prof. T. H. Huxley, F.R.S., 417 ; the Proposed Statue of, 435 Hatfield (H.), Meteor, 342 Hauer (F. R. von), «' Die Geologie," 78 Hayden (Dr.) Geological Work of the U.S. Survey in 1877, 129 Head-Masters on Science Teaching, Rev. W, Tuckwell, 317 Hearing and Smell in Insects, lienry Cecil, 102, 381 Heat, B. Loewy, 43 Heat, Evolution of, during Muscular Action, Prof. A. Fick, 285 Heat-Motion, on a Means of Converting the, Possessed by Matter at Normal Temperature in Work, S. Tolver Preston, 202 ; John Aitken, 260 Hebrides, Low Barometric Readings in the, Nov., 1877, 307 Hecla, Mount, Eruption of, 454 Heddle (Prof. M. Forster), Glaciation of Orkney, 182 Heidelberg, University of, 195 Helmholtz (Prof. H., F.R.S.), Lord Rayleigh's "Theory of Sound," 237; Helmholtz's Vowel Theory and the Phonograph, 384, 411, 423 Henderson (Richard) Manual of Agriculture, 280 Hennessey (J. B. N., F.R.S.), Optical Spectroscopy of the Red End of the Solar Spectrum, 28 Henry Telephone, 437 Hensen (M,), the Earthworm in Relation to the Fertility of the Ground, 18 Henslow (Rev. G.), on the Self-Fertilisation of Plants, 221 Hering (M.), on the Sense of Temperature, 372 Hermann (Otto), Hungarian Spiders, 128 Herring Fisheries and the Telegraph, 351 ; the Swedish, 391 Herschel (Prof. A. S.), the " Phantom" Force, 302, 321, 340 Hicks (Henry), Dimetian and Pebidian Rocks of Pembroke- shire, 155 Higgins (H. H.), " Notes by a Field Naturalist in the Western Tropics," 121 High Tides, Prediction of, 38, 45, 58, loi Hildebrandt (Dr. J. M.), Ascent of Mount Kenia, 72 ; Explo- ration of Africa, 194 Hilgard (J. E.), Transatlantic Longitudes, 244 Hind (J. R., F.R.S.), Wolf's "History of Astronomy," 259 (Translation), 359 Hinde (G. J.), Earthquake in Canada, 90 Hinduism, Buddhism, and Islam, 239 Hippopotamus, Death of, in the Zoological Gardens, 392 Hissarlik, Antiquities from, 397 Hofmann (Prof. A.), a " Commers " in Honour of, 393 Hofmeister's Cryptogamia, 344 Holden (J. Sinclair), Strychnia and its Antidote, 360 Hollis (W. Ainslie), Supplementary Eye-brows, 124 Hopkins, Johns, University, Baltimore, Anniversary, 459 j Fel- lowships at, 517 Horology, Modern, M. Claudius Saunier, 484 Horse-Shoe Crabs, 289 " Horticulture," F. W. Burbidge, 142 Hovelacque (Abel), the Science of Language, 464 Howgate (Capt,), Arctic Expedition, 153, 171 Hubbard (E.), the Wasp and the Spider, 402 Humboldt Institution for Naturalists and Travellers, 311 Hungary: Spiders of, 128; Rotifers of, 128 Hunter (Dr. W. W.), Rainfall in the Temperate Zone in Con- nection with the Sun-spot Cycle, 59 ; Great Waterfalls, 242 Hunterian Lectures for 1878, 350 Huxley's "Physiography," 178 Hydrophobia, 117, 139 Hygrometer, a new Condensing, 14, 28; M. AUuard's, 132 Ice : as an Electrolyte, 56; R. Pictet on the Formation of 154; Production of, 212 Iceland: Volcanic Eruption in, 171; no Butterflies in, 243, 260 Ilford Fossils, Dr. R. P. Cotton's Collection of, 231 Index Society, 37 India : Methods for Determining Solar Radiation in, 131 ; the Rainfall of, 273, 505 ; the Climate of, 307 Indium in British Blendes, Prof. N. S. Maskelyne, F.R.S., 5 "Inductive Metrology," Flinders Petrie, 357 Indus River, 38, 250 . " Industrial Art," 272 Inflexible, the, 131, 137 Ingleby (Dr. C. M.), Philadelphia Diplomas, 183 Injurious Insects, Report on, 330 Innsbruck University Statistics, 25-1 Insectivorous Plants, Francis Darwin, 222 Insects : and Flowers, 1 1 ; Fritz Mliller on Insects and Flowers, 78 ; Insects, Hearing and Smell in, Henry Cecil, 102, 381 ; Insects and Artificial Flowers, 133, 162 ; Selective Discrimina- tion of Insects, 62, 163, 402, 425 ; Insect Fauna of Chili, R. McLachlan, F.R.S., 162; A. R. Wallace, 182; Insects of Chili and New Zealand, 221, 260 ; Sense in, W. M. Gabb, 282; Report on Injurious, 330; Digestion in, 411 Institute of Chemistry, 273, 291, 309 Institute of Civil Engineers, 54, 76, 156, 215, 276, 356, 416, 460, 500, 520 International Geological Congress, 65 International Polar Expeditions, E. J. Reed, C.B., M.P., 29 lodates of Cobalt and Nickel, 150 Iquique, Earthquake at, 90, 272 Iron and Steel Institute, 436, 458 Iron, Red-hot and Light, 17 Iron Ships, Compass Adjustment in, Sir William Thomson, F.R.S., 331, 352, 387 Iron, the Fracture of, 491 Islam and its Founder, J. W. H. Stobart, 239 Island, a Volcanic, 194 Isomerism, Influence of, on the Formation of Ethers between Acids and Alcohols, 151 Italian Cryptogamic Society, 491 Italian Geographical Society, 37, 132 Jack (Robert L.), Research in Libraries, 486 Jackson (J. G.), the Great Pyramid, 243 Jahrbiicher f. wissenschaftliche Botanik, 158 Jahresbericht fiir Chemie, 171 Janssen's Researches on the Sun's Photosphere, J. Norman Lockyer, F.R.S., 23 Japan: Edward S. Morse on Traces of Early Man in, 89; Exploration of, 171 ; Archaeological Society in, 271 ; Geo- graphical Work in, 290 ; Japanese Students in England, 491 Jena, University Statistics, 254 Jenkins (Prof. Fleeming) and J. A. Ewing on Helmholtz's Vowel Theory and the Phonograph, 384, 423 Jenkins (B. G.), Expected High Tides, 45, loi ; Sun-spots and Terrestrial Magnetism, 259 Jersey, Earthquake in, 272 Jewell (Lieut. Theo. F.), Sounding Apparatus, 230 \ Johns Hopkins Scientific Association, 113 Joliet (M. L.), French Polyzoa, 382 Jordan (Dr. D. S.), the Distribution of Freshwater Fishes, 128 Journal de Physique, 294, 314 Journal of Forestry, 153 Judd (Prof. J. W„ F.R.S.), the Strata of the Westeni Coast and Islands of Scotland, 335 Jupiter's Satellites, 149. " Kames " in Connecticut, 213 Kampf (Dr. Frederick), Death of, 513 Kant (Immanuel), Proposed Monument to, 391 "Katzen, Das Buch der," 351 Keane (A. H.), Translation of Hovelacque's Science of Language, 464 Kekule (Prof.), on the Position of Chemistry, 55 Kelsief (M.), Exploration of Russia, 38 Kenia, Mount, Dr. J. M. Hildebrandt's Ascent of, 72 Nature, May 30, 1878] INDEX JX Kent (W. Saville), Sound-producing Arthropods, 11 ; a Zoolo- gical Station for the Channel Islands, I02 Kern (Sergius), Davyum, 245, 292 Key (Rev. Henry Cooper), the Earthworm in Relation to the Fertility of the Soil, 28 Kieff, University Intelligence, 374 Kirtland (Dr, J. P.), Obituaiy Notice of, 232 Knots, Trefoil, 421 Koenig and Appunn — Beats in Confined Air, Alex. T. Ellis, F.R.S., 26 Konigsberg, University Intelligence, 55, 478 Korostovtseff (M.), Exploration of the Northern Pamir, 249 Kosmos, 20, 254, 374 Krupp's Workshops, Statistics of, 351 Kuhlmann (Prof.), Collection of his Researches, 437 Kurz (Sulhiz), Death of, 391 Lagrange, the Statue of, 53 Laing (S, M. P.), Glacial Geology of Orkney and Shetland, 123 Lake-Dwellings, English, and Pile Stnictures, Prof. T. Rupert Jones, F.R.S,, 424 Lakes, Depths of, 468 Lalande, the Star, 382, 488 Lamps, Lighting by Electricity, 108 Lamy (Prof. A.), Death of, 436 Landslip near Cork, C. J. Cooke, 425 Land-Tortoises, Gigantic, Dr. Giinther, F.R.S. , 483 Landvort (M. Schoun), Death of, 170 Langdon (W, E.), the Application of Electricity to Railway Working, 461 Language, the Science of, Abel Hovelacque, 464 L'Annee Geographique, 1876, 489 Lapland, Exploration of Russian, 345 Laplanders at the Westminster Aquarium, 70 Last of the Gases, 177 Lava, Mineral Oil in, at Mount Etna, 150 Lebour (Prof. G. A.), Marine Fossils in the Gannister Beds of Northumberland, 320, 352 Leeds, Yorkshire College of Science, 175 Leicestershire and Rutland, Harrison's Geology of, 58 Leidenfrost's Phenomena, Wm. Garnett, 466 Leipzig, University Intelligence, 95 Levels, Bubbles of Air in, 233 Leverrier, the Pension to his Widow, 52 ; Proposed Monument to, 350. 391 Leverrier (Madame), Death of, 37 Lexington, U.S., Endowment of the University, 175 Library, Statistics of the Paris National, 92 Libraries of German and Austrian Universities, 374 Libraries, Research in, Robert L. Jack, 486 Liebig, the Proposed Monument to, at Munich, 16 Liebreich (Dr. R.), the Deterioration of Oil Paintings, 493, 515 Liesthal, Earthquake at, 475 Lighting Lamps by Electricity, 108 Light, Chemical Action of, 151, 436; the Sources and Reflec- tion of, Mayer and Barnard, 405, 427 ; Action of, on a Selenium (Galvanic) Element, Robert Sabine, 512 ; Experi- ment on Light and Electricity, 233 Lime, Strontian, and Baryta, Crystallisation of, 372 Limestone Rock, the Origin of a. Prof. W. C. Williamson, F.R.S., 265 Lindsay (Lord), his Dun Echt Observatory Publications, 432 Lingula, Structure of, 383 Linne, Centenary of his Death, 210, 271 Linnean Society, 55, 155, 175, 235, 315, 355, 394, 439, 499, 519 ; and the Centenary of Linne, 309 Liquefaction of Air and of the so-called Permanent Gases, Prof. T. E. Thorpe, F.R.S., 384 Liquefaction of Oxygen, &c., 169, 177, 265 Liquids, Compressibility of, M. Amagat on, 91 ; Thermo-elec- tric Properties of, G. Gore, F.R.S., 479; Volume of and the Absorption of Gases, 514; the Concentration of, and their Electromotive Force, 515 Lisbon, Earthquake at, 1 7 Littrow (Carl von), Obituary Notice of, 83 Liveing and Dewar (Piofs.), on the Reversal of the Lines of Metallic Vapours, 498 Liver, the Glycogenic Function of the, 439 Liverpool Historic Society, 193 Lizard, the Bermuda, G. Brown Goode, 425 Lloyd (W. A.), the Proposed Channel Islands' 2^ological Sta- tion, Aquarium, and Piscicultural Institute, 143 Lloyd (Dr.), Scientific Papers of, 272 Lob-Nor, Lake, Expedition to, 234, 434 Lockyer (J. Norman, F.R.S.), the Sun's Photosphere, 23 ; the Modern Telescope, 66, 125, 188, 225 ; the Use of the Reflec- tion Grating in Eclipse Photography, 354 ; the Coming Total Solar Eclipse, 481, 501 Locomotive Engine, Quick Mounting of, 438 Locust Plague in America, Andrew Murray, 377 Loewy (B.), "Heat," 43 Lohrmann's Lunar Charts, 343 London, University of, 19 London Clay Fossils, 487 Longitudes, Transatlantic, 244, 408 Lubavin (N. N.), "Physical Chemistry," 240 Lubbock (Sir John, F.R.S.), Habits of Ants, 355 Lunar Charts, Lohrmann's, 343 Lunar Landscape, Winkler's, 469, 514 Lyons Observatory, 149 Macalister (Prof. Alex.), Royal Dublin Society, 183 McCook (H. C), the Agricultural Ants of Texas, 433 ; the Aeronautic Flight of Spiders, 434 McKendrick (Prof. J. G.), Telephonic Alarum, 181 Mackennah (A.), Explosions, 123 McLachlan (R., F.R.S.), Insect Fauna of Chili, 162, 182; on some Pecular Points in the Insect Fauna of Chili, 260 Maclear (Commander J. P.), Spectrum of Aurora Australis, 11 McNab (Prof. W. R.), Baker's Flora of Mauritius and Sey- chelles, 77; Botany in Germany, 158; Oliver's Flora of Tropical Africa, 319 Macrosilia cluentms. Dr. Hermann Muller, 221 Madagascar, Hartlaub's Birds of, 9 Madrid, Annual Report of the Observatory of, 70 Magnet, a New, 252 Magnetical Measurements in Russia, 153 Magnets, Floating, Alfred M. Mayer, 487 Mahwa Tree, 394 Maisonneuve (M. C. Durieu de). Death of, 436 Male Nurse, a, 222 Malt, Explosion of, A. Mackennah, 123 Mammal, the Brain of a Fossil, 222 Mammoth Remains in Tomsk, 153 Mammoth, Discovery of a Fossil, in Hanover, 273 Man, Traces of Early, in Japan, 89; Antiquity of Man, 315 Manchester, Chemical Society at Owens College, 114; Literary and Philosophical Society, 96, 176, 296 Manjean (M.), Bequest to the French Institute, 70 Manfredonia, a Buried City near, 211 Manuscripts, Restoration of the Handwriting of, 351 Maps of the Balkan Peninsula, 346 Maps, Ancient, of Central Africa, 383 Marburg, University Statistics, 478 Mareotis, Lake, Proposed Draining of, 212 Marine Fossils in the Gannister Beds of Northumberland, Prof. G. A. Lebour, 320, 352 Marjoram and Thjnne, Fertilisation in, 127 Marmora (Gen. La), Death of, 211 Mars, the Satellites of, 15, 190, 231, 288, 433 ; the Planet, and B.A.C. 8129, 105 ; the South Polar Spot of, 209 Marseilles, Proposed Zoological Garden at, 474 Marsh (Prof. O. C), Brain of a Fossil Mammal, 340 Marshall (Dr. A. M.), the Development of Nerves, 382 Martini (Prof. Tito), Diffusion Figures in Liquids, 87 Maskelyne (Prof. N. S., F.R.S.), Indium in British Blendes, 5 Mathematical Society, 95, 155, 254, 336, 400, 459 Mauritius and Seychelles, the Flora of, by J. G. Baker, 77 Maxwell (Prof. Clerk, F.R.S.), an Electrical Experiment, 180; Tail's "Thermodynamics," 257, 278 Mayer (Alfred M.), Edison's Talking Machine (the Phonograph), 469 ; Floating Magnets, 487 Mayer and Barnard, the Sources and Reflection of Light, 405, 427 Mayer (Robert Julius v.), Death of, 435 ; Obituary Notice, 450 Mayer (Dr. Paul), Entomological Query, 467 Mechanical Analysis of the Trevelyan Rocker, Samuel II. Frisbee, 242 Medusae, Prof. Eimer on the Nervous System of, George J. Romanes, 200 INDEX \Naturty May 30, 1878 Meldola (R.), Oxygen in the Sun, 161 Meldrum (C, F.R.S.), Sun-spots and Rainfall, 448 Mello (Joaquim Correa de), Death of, 309 Melo-Piano, the, 453 Memorie della Societa degli Spettroscopisti Italiani, 314 Mercury, the Transit of, on May 6, 1878, 46, 69, 363, 370, 488 Merriman (Mansfield), List of Writings on the Method of Least Squares, 219 Merten, Excavations at, 475 Metallic Vapours, the Reversal of the Lines of the, Professors Liveing and Dewar, 498 Meteorites, see Meteors Meteorology: Meteorological Notes, 15, 248, 307, 362, 489; Meteorological Society, 134, 235, 295, 356, 499; Meteorology of New York, 15 ; Meteorology in Russia, 16; Prof. Monier Williams on Indian, 53 ; Meteorological Phenomena, 82 ; New Meteorological Observatory at Fiesole, no; Daily Warnings in France, 133; French Meteorology, 170, 193; Climatology of the Spanish Peninsula, 248 ; Climatology of the Fiji Islands, 248 ; United States Volunteer Weather Service, 248 ; Rainfall of India, 273 ; the Progress of Meteo- rology, 313; Bulletin of the Montsouris Observatory, 362; Meteorology of Western Australia, 363 ; Agricultural Weather W^arnings in France, 371 ; Proposed French Institute of, 391 ; Scottish Meteorological Society, 440 ; Meteorology of Stony- hurst, 489 ; Weekly Statistics of the Weather, 489 ; Missouri Weather Reports, 490 ; Comparative Atmospheric Pressure of New Zealand and Great Britain, 490 ; Popular Meteorology in Switzerland, 492 Meteors: 29, 94, 124, 221, 342, 425, 454, 467, 487; of October 19, 1877, 10 ; Meteorite of July 20, i860, 104 ; Meteorite of June 14, 1877, 150; of December 6, 1877, 152; the Meteor of November 23, 1877, 94, 113, 183, 246; Meteor in Virginia, 214 ; the Daylight Meteor of March 25, 467 Method of Least Squares, Merriman's List of Writings Relating to, 219 Metrology, Flinders Petrie on Inductive, 357 Metropolitan Sewage, 157 Meudon Observatory, 392 Mexico, New, Exploration of, 489 Meyer (Dr. A, B.), Mittheilungen aus dem k. zoologischen Museum zu Dresden, 142 Mice, Singing, II, 29 Michaud (M. Narcisse), Death of, 474 Michel (Gustav), " Die Buch der Katzen," 351 Microscopical Society, see Royal Microscopical Journal, Decease of the, 152 Midian, Capt. Burton's Exploration of, 53, 132 " Midland Naturalist," 233, 438 Millar (W, J.), a Telephone without Magnetism, 242 Millepora, Effects of the Urticating Organs of, on the Tongue, L. P. Pourtales, 27 Mills (Prof., F.R.S.), Electrostriction, 235 Miln (James), Archaeological Researches at Carnac, 379 Mimicry in Birds, 361, 380, 478, 486, 507 Minchin (G. M.), Potential Energy 27 Mineral Oil in a Lava of Mount Etna, 150 Mineralogical Society, 376 Mines, Telegraphic Warnings in, 16; Explosions in, W. Galloway, 21 "Minhocao," the, 325 Minor Planets, 36, 46, 63, 83, 210, 306, 344, 382, 488, 507 Missouri : Geological Survey of. Prof. Arch. Geikie, F.R.S., 431; Weather Reports, 493 Mittheilungen aus dem k. zoologischen Museum zu Dresden Dr. A. B. Meyer, 142 ' Mivart (Prof. St. G., F.R.S.), on the Fins of Elasmobranchs, 355 Mohn (Dr. IL), Norwegian Deep-Sea Expeditions, 30; Meteoro- logical Observations in the North Atlantic, 235 Moll (J. W.), Researches on the Carbon of Plants, 344 Molybdenum, 270 Mongolia and Siberia, Exploration of, 435 Monistic Philosophy, Prize for Treatise on, 70 Monotremata of Australia, E. P. Ramsay, 401 Monster, a New Underground, 325 Monteiro (Joachim John), Death of, 391 ; Obituary Notice of 425 Montsouns Park and Observatory, 132 ; Meteorological Bulletin of, 362 Monuments, George Smith's Ancient History from the, 119 Moon, a Lunar Landscape, 469, 514 Morning Dawn, the Expedition of the, 153 Morphologische Jahrbuch, 39, 294, 478 "Morphology of the Skull," Parker and Bettany's, 3 Morse (Edward S.), Traces of Early Man in Japan, 89; the Structure of Lingula, 383 Moscow, Anthropological Exhibition in, 16, 171 Moscow and the Volga, Communication between, 91 Moseley (H. N., F.R.S.), "Drowned by a Devil Fish," 27; Oregon, 302 ; Origin of Trachese in Arthropoda, 340 Mosquitos and Filarioe, 439 Mosses and Ferns, Ilofmeister's Work on, 344 Moths, Smell and Heaving in, 45, 62, 82 Mott (F. T.), Meteor, 467 Mount Etna, Mineral Oil in a Lava of, 150 Mount Tongariro, N.Z., 346 Moving Diagrams of Machinery, 158 Moyobamba, the Rain-Tree of, Prof. Thiselton-Dyer, 349 Muir (M. M. Pattison), Proctor's "Spectroscope and its Work," 360 Miiller (Fritz) on Flowers and Insects, 78 Miiller (Dr. Hermann), Fertilisation in Thyme and Marjoram, 127; Macrosilia chientius, 221 Munich, University Statistics, 275, 478 Miinster, University Intelligence, 354 Murphy (J. J.), Meteorological Phenomena, 82 Murray (Andrew), Obituary Notice of, 232 ; the Locust Plague in America, 377 Musaceae, Products of Assimilation in, 127 Muscular Action, the Evolution of Heat during. Prof. A. Fick, 285 Museums, the Arrangement of, Gen. A. Lane Fox, F.R.S., 484 Music : Music a Science of Numbers, Wm. Chappell, 32 ; Musical Association, 331 ; Grove's Dictionary of Music, Dr. W. H. Stone, 422 ; an Organ-Piano, 453 ; State Aid to Music, Alan S. Cole, 474 Musk-deer, Discovery of a Skeleton of the Pre-historic, 455 Mussel, the Byssus in the, 289 Musters (Capt.) on Bolivia, 90 "Mycenae," Dr. Schhemann's, 397 Myopia in Germany, 310 " Myths and Marvels of Astronomy," R. A. Proctor, 180 Naples, the Zoological Station at. Dr. Anton Dohrn, 329, 360 Natural History, Cassell's, vol. i., 365 Natural History Journal, 392 Natural Phenomena, Electrical Analogies with, 226, 385 Nautical Almanac for 1881 Navicula (?), Mr. W. W. Wood on a Species of, 392, 437 Neander Valley, the Collection of Remains from, 108 Nebulae and Clusters, Literature of the, 288 Nebulae, Variable, 306 Nemirovich-Danchenko (M.), "The Land of Cold," 211 "Nerthus," the, of Tacitus, 250 Nerves, the Development of, 382 Nettle, the Common, Experiments on the Fibre, 351 Neumagen, Excavations at, 292 Neumayer (Dr. G.), the Progress of Meteorology, 313 New Guinea, 250, 383 ; Gould in, 408 ; Exploration of, 435 New Mexico, Exploration of, 489 New South Wales, Royal Society of. Proceeding's, 17 New York, Meteorology of, 15; Proposed Zoological Garden in, 192 ; Natural History Museum, 232 ; Survey of, 508 New Zealand, Mount Tongariro, 346 ; Comparative Atmospheric Pressure of, and Great Britain, 490 Newcomb (Prof. S.), elected F.R.S., 150; Lunar Researches, 209 ; Theorems relating to Geometry of Three Dimensions, 240 Newton (Prof. A., F.R.S.), Hartlaub's "Birds of Mada- gascar," 9 ; No Butterflies in Iceland, 260 ; Mimicry in Birds, 380, 507 Niagara Falls, the Plorseshoe, 109 ; Curious Phenomenon at, 454 Nias Island, 290 Nickel, M. H. Wild's Researches on, 393 Nickel and Cobalt, lodates of, 150 Nicols (Arthur), Eucalyptus, 10, 342 Nicotin, Physiological Action of, 222 Nightingale, the, 487 Nitrification, R. Warington, 367, 40? Nature, May 30, 1878] INDEX XI Nitro-benzoic Acid, the Fourth, 151 Niven (W. S.). Trajectories of Shot, 466 Nocturnal Increase of Temperature with Elevation, Dr. E. Bonavia, 10 1 Noeggerath (Prof. Jacob), Proposed Monument to, 170 Nordenskjold (Prof.), Expedition to the Arctic Regions, 90 Northumberland, Marine Fossils in the Gannister Beds of. Prof. G. A. Lebour, 320, 352 Norway, Glacial and Post-GIacial Fishes of, 509 Norwegian Deep-Sea Expeditions, H. Mohn, 30 Norwegian North Sea Expedition, 253 Nova Cygni, 46 Novaya Zemlya, Colonisation of, 109 Noye (Thos.), a Double Rainbow, 262 Nuttall Ornithological Club, Bulletin of, 498 Nyassa, the Lake of, 435 O'Brien (C. G.), Fetichism in Animals, 402 ; Discrimination of Insects, 402 Observatories : Paris, 69, 109, 131, 152, 193, 232, 473 ; Madrid, 70; the Cordoba, 83, 209; Montsouris, 131; Lyons, 149 ; Cape of Good Hope, 269 ; Brussels, 288 ; the Temple, 324 ; the Radcliffe, 363 ; Harvard College, 363 ; Meudon, 392 ; Dun Echt, 432 Octopus, Drowned by an, 27, 282 Oil Paintings, the Deterioration of. Dr. R. Liebreich, 493, 515 Old Red Sandstone of Western Europe, Prof. A. Geikie, F.R.S., 471 Oliver (Prof. D., F.R.S.), " Flora of Tropical Africa," Prof. W. R. McNab, 319 Olympia, the Excavations at, 330 Ontario, Report of the Registrar-General, 455 Optical Spectroscopy of the Red End of the Solar Spectrum, J. B. N. Hennessey, F.R.S., 28 Oregon, H. N. Moseley, F.R.S., 302 Organ-Piano, an, E. J. Reed, M.P., F.R.S., 453 Organic Liquids, Distillation of, by Means of Steam, 270 Oriental Affinities in the Ethiopian Insect-Fauna, W. L. Distant, 282 Orkney and Shetland, Glacial Geology of, S. Laing, M.P., 123 ; Prof. M. Forster Heddle, 182 Ornithuric Acid, 270 Orograph, a new Form of, 1 56 Orton (Prof. James), Death of, 90 " Our Native Land," 491 Owen (Prof., F.R.S.) on the Modification of a Lower Form of Life by a Higher, 375 Oweas College, Chemical Society at, 1 14 Owls, M. A. Milne-Edwards on, 345 Oxford : University Commission, 19 ; proposed High School for, 19, 39; University Intelligence, 114, 194, 334, 393, 415 ; University Statistics, 354 Oxidation, Acceleration of, caused by the least Refrangible End of the Spectrum, Capt. Abney, F.R.S., 518 Oxygen, the Presence of, in the Sun, Dr. Arthur Schuster, F.R.S. , 148; R. Meldola, 161; Dr. Henry Draper, 339; in Sea-Water, T. Y. Buchanan, 162 ; Liquefaction of, 169, I77> 265; the Density of Liquid, 217; the Influence of, on Respiration, 252 Page (F. J. M.), Demonstration of Currents Originated by the Voice in Bell's Telephone, 283 ; the Action of the Telephone on a Capillary Electrometer, 395 Palmen on the Morphology of the Tracheal System, 284, 340 Pamir, the Exploration of the, 249, 324 Paper Trade, International Exhibition of the, 371 Papuan Plants, 289 Parker and Bettany's " Morphology of the Skull," 3 Paris: Academy of Sciences, 20, 40, 56, 70, 76, 96, 1 16, 136, 156, 195, 216, 236, 251, 256, 276, 316, 356, 376, 396, 409, 416, 440, 460, 480, ,500, 520; Vacancy in, 70; Prizes of the 294, 373 ; the Eloge on Buffon, 474. Geographical Society of Paris, 17, 346, 384, 468. Paris International Exhibition, 37 ; the Russian Division in, 350 ; Representation of Science at, 357 ; " £tudes sur I'Exposition de 1878," 371 ; Arabs at, 454. Congresses at Paris, 474 ; Paris Observatory, 69, 109, 131, 152, 193, 232, 473; the New Transit Circle at, 165. Statistics of the National Library, 92. Telegraphic Warnings of Fires in, 91. Ethnological Museum in the Palais de I'lndustrie, 272, Lectures on Ethnography in, 330. Societe d'Hygiene, 310. Statistics of the Press, 311. Elec- tric Lighting in, 437. Association d'Exau"sions Scientifiques, 454. Museum of the Jardin des Plantes, 455. the Tuileries Captive Balloon, 454, 491. Underground Railway in, 492 Pears, Fungoid Disease of, 91 Pembrokeshire, Dimetian and Pebidian Rocks of, 155 Peronospora, the Fossil, as a Primordial Plant, Worthington G. Smith, 144 Persimmon, the Persian, 508 Pesth, Artesian Well at, 109 ; Centenary of the University, 134 Petermann's Mittheiluiigen, 17, 90, 253, 408 Petrie (W. M. Flinders), "Inductive Metrology," 357; Age of the Earth, 465 Petty (T. S.), the Meteor of November 23, 183 "Phantom" Force, the. Prof. A. S. Herschel, 302, 321, 340 Pharmaceutical Society, 410 Phenological Observations during 1877, 236 Philadelphia : Academy of Natural Science, 296 ; Philadelphia Diplomas, Dr. C. M. Ingleby, 183 ; Dr. Richard C. Bran- deis, 221 Phipps (Geo. H.), the Earth-worm in Relation to the Fertility of the Soil, 62 Phoneidoscopic Representation of Vowels and Diphthongs, 447, 486 Phonograph : Edison's, 90, 190, 291, 41$, 469, 485 ; and Helm- holtz's Vowel Theory, Prof. Fleeming Jenkin and J. A. Ewing, 384, 423 Phosphides of Tin, 151 Photography : Photography of Natural Colours, 92 ; Photo- graphic Society, 195, 276, 376, 479 ; Photography Fore- shadowed, Dr. J. A. Groshans, 202 ; J. Rand Capron's "Photographic Spectra," 259; Abney's "Photography," 378 ; " Photographic Rays of Light," 438 Phylloxera in Germany, 211 "Physical Chemistry," N. N. Lubavin, 240 Physical Society, 55, 115, 135, 175, 295, 394, 415; Annual Meeting, Officers, &c., 315 Physician's Experiment, 305 "Physiography," Huxley's, 178 Physiological Tables, Dr. E. B. Aveling's, 5 Physiological Teaching and the Cruelty to Animals' Act, Frank W. Young, 45 Piano, an Organ, E. J. Reed, M.P., F.R.S., 453 Pic-du-Midi Observatory, 409 Pictet (M. Raoul), on the Liquefaction of the Gases, 292 ; Honorary Degree to, 436 Pidgeon (D.), the Phonograph, 415 Pig-iron, Separation of Phosphorus from, 459 Pigott's Observations of Variable Stars, 323 Pile-Dwellings, and English Lake-DweUings, Prof. T. Rupert Jones, F.R.S., 424 "Pioneering in South Brazil," T. P. Biggs-Wither, 423 Pirani (Prof. F. J.), an Electrical Experiment, 180 Piscicultural Institute, the Proposed Channel Isles, W. A. Lloyd, 143 Pitch, Absolute, Lord Rayleigh, F.R.S., 12 Pitury, the new Stimulant, 492 Planets, Minor, 46, 63, 83, 210, 306, 344, 382, 488, 507 Plant and Animal Life, Analogies of, Francis Darwin, 388, 41 1 Plante (M, Gaston), Electrical Analogies with Natural Pheno- mena, 226, 385 Plants : Ferment in, 455 ; the Carbon of, 344 ; Self-Fertilisa- tion of, 221 ; the First Stages of Development in, 433'j Plateau Films, Permanent, 175 Plestiodon longirostris, 425 Plummer (J, L), Aid of the Sun in Relation to Evolution, 303, 360 Poaching Birds, 509 Polar Expeditions, International, E. J. Reed, C.B., 29 Polyzoa, French, 382 Pongo, Death of the Gorilla, 70 ; Dissection of, 89 Potential Energy, 9, 27, 81 Pouchet, Monument to, 108 Pourtales (L. P.), Effiscts of the Urticating Organs of Millepora on the Tongue, 27 Powell (Major J. W.), Ethnology of North America, 53 Preston (S. Tolver), on a Means of Convening the Heat Motion Possessed by Matter at Normal Temperatiu-e into Work, 202 ; on the Diffiision of Matter in Relation to the Second Law of Thermodynamics, 31 ; the Age of the Sun's Heat in Relation to Geological Evidence, 423 Xll INDEX \_Nature, May 30, 1878 Pringsheim (Dr. A.), Jahrbucher fur wissenschaftliche Botanik, 158 Prjwalsky's Journey to Lob-Nor and Tibet, 153, 434 Proctor (R, A.), "Myths and Marvels of Astronomy," 180; " The Spectroscope and its Work," 360 Protection of Animals, Vienna Society for the, 293 Prussia, the Universities of, 55, 294 Ptolemy's Geography of English Coast, 193 Punjab, the Upper, the Geology of, 395 . Purple Dyes of Antiquity, 133 Pyramid, the Great, J. G. Jackson, 243 Quaritch (Bernard), Faraday's "Experimental Researches," 342 Quarterly Journal of Microscopical Science, 37, 214, 254 Radcliffe Observatory, 363 Radiant Heat, the Thermo-electric Pile and the Radiometer, 310 Radiometer : and its Lessons, 5, 7, 26, 27, 43, 44, 61, 79, 121, 142, 143, 181, 199, 220, 261 ; Prof. G. G. Stokes, F.R.S., on Certain Movements of Radiometers, 1 72, 234 ; and the Thermo-electric Pile, 310 Rae (Dr. J.), Tuckey, and Stanley, the Yallala Rapids on the Congo, 62 ; No Butterflies in Iceland, 243, 260 Railway Brakes, 410, 507 Railway Collisions and Electricity, 371 Railway Working and Electricity, W. E. Langdon, 461 Railways, Underground, in Paris, 492 Rainbow, a Double, Thos. Noye, 262 Raindrops, Hailstones, and Snowflakes, the Formation of. Prof, Osborne Reynolds, F.R.S., 207 Rainfall in the Temperate Zone in Connection with the Sun-spot Cycle, Dr. W. W. Hunter, 59 Rainfall, Contribution to the Sun-spot Theory of Rainfall, Dr. E. Bonavia, 61 Rainfall of India, 273, 505 Rainfall and Sun-spots, 443 ; C. Meldrum, F.R.S., 448 ; Alex. Buchan, 505 Rain-tree of Moyobamba, Prof. T. Thiselton Dyer, 349 Ralton (Dr.), " Handbook of Common Salt," 302 Ramsay (E. P.), Australian Monotremata, 401 Ramsay (Prof., F.R.S.), and James Geikie, F.R.S., on the Geology of Gibraltar, 518 Raspail (M. F. V.), Death of, 212 Ratti (Aurel de), the Telephone, 380 Rayleigh (Lord, F.R.S.), Absolute Pitch, 12; "Theory of Sound," Vol. I., Prof. H. Helmholtz, F.R.S., 237 Reade (T. Mellard), the Challenger Estimates of the Volume of the Gulf Stream, 144 Reale Istituto Lombardo di Scienze e Lettere, 294, 374, 478, 498 Reed (E. J., C.B., F.R.S.), International Polar Expeditions, 29 ; an Organ Piano, 453 Reflection Grating, the Use of, in Eclipse Photography, J. Nor- man Lockyer, F.R.S., 354 Reflectors, Glass for, Henry Bessemer, 241 Regnault (M. Victor), Death of, 250 ; Obituary Notice of, 263 Reichenbach's Odyle and Mr. Wallace, 8 ; Wm. B. Carpenter, F.R.S., 8, 44 Reilly (P. W.), a Meteor, 221 Research Fund, the Government, 403 Research in Libraries, Robert L, Jack, 486 Respiration, Aquatic, 290 Revue Internationale des Sciences, 152, 212 Reynolds (Prof. J. Emerson), Frankland's Researches in Che- mistry, 218, 318 ; Discovery of a New Explosive, 436 Reynolds (Prof. Osborne, F.R.S.), the Radiometer and its Lessons, 27, 61, 121, 220; on the Formation of Hailstones, Raindrops, and Snowflakes, 207 Rheostatic Machine, 40 Rhine, the Fisheries of the, 212 ; Method for Determining the Impurities of, 131 Rhinoderma darwinii, 222 Rhizopods in an Apple Tree, 434 "Rider," the, in Egyptian Balances, 455 Riley (Charles V.), the Locust Plague in America, 377 Rink (Dr. Henry), Danish Greenland, 57 Roads, Machine for Levelling, 392 Roberts (Edward), Expected High Tides, 58 Rocky Mountains, Geology of the, 39 Rohlfs (Herr G.), Expedition to the Libyan Desert, 290 Romanes (G. J.), Singing Mice, 29; Smell and Hearing in Moths, 82; Fetichism in Animals, 168; Prof. Eimer on the Nervous System of Medusae, 200 Romanis (James M.), on a New Form of Telephone, 20I Romer (Ole), Dr. Doberck, 105 Rontgen (Dr. W. C), a Telephonic Alarum, 164 Rosthorn (Francis von). Obituary Notice of, 1 1 Rotifers or Wheel -Animalcules of Hungary, 128 Royal Astronomical Society, 76, 195, 27.5, 309, 459 Royal Dublin Society, 46, 183 Royal Geographical Society : and the Public, 38 1 ; Medals of the, 467 ; School Prize Medals, 497 Royal Institution, 170, 291, 371 Royal Microscopical Society, 56, 156, 236, 336, 416 Royal Society : 37, 134, 214, 235, 314, 335, 354, 415, 479, 498, 518 ; Council of, 37 ; Medals of the, 69 ; the Times on the, 108 ; Election of Foreign Members, 151 ; New Fellows, 513 Royal Society of Edinburgh, 153 Rubies, the Artificial Production of, 152 Rugby, the Temple Observatory, 324 Ruhmkorff (Henry David), Obituary Notice of, 169; Sale of his Workshop, 351 Russell (Mr., Astronomer-Royal at Sydney), Attempt on his Life, 152 Russell (Hon. Rollo), Telephonic Experiments, 292 Russia : Meteorology in, 16 ; Exploration of, 38 ; Russian Geographical Society, 53, 153, 171, 194, 213, 324; Primary Education in, 53 ; Gems from, 72 ; Magnetical Measure ments in, 153 ; St. Petersburg Society of Naturalists, 194 ; University of Charkow, 195 ; Nemirovich-Danchenko's "The Land of Cold," 211 ; Russian Chemical Society's Journal, 251; Russian Anthropology at the Paris Exhibition, 350; Ethnology of, 468. See also St. Petersburg, Moscow, &c. Rutland and Leicestershire, Harrison's Geology of, 58 Ryder (John A.), the Laws of Digital Reduction, 128 Rye (E. C), Wollaston's " Coleoptera Sanctse-HelleucX," 338 Sabine, (Robert), the Telephone, 379 ; Action of Light on a Selenium (Galvanic) Element, 512 Sachs (Prof.), called to Berlin, 75 St, Andrews, University Intelligence, 95 St. Elmo's Fire, 436 St. Helena, Wollaston's "Coleoptera SanctDS Hellense," 338 St. Paul and Amsterdam, the Islands of. Prof. E. Perceval Wright, 326 St. Petersburg, University Intelligence, 55 ; Society of Natural- ists, 194 ; New High School for Ladies, 195 ; Education of Women at, 195, 334 ; New Archaeological Institution, 329 ; the Central Physical Observatory, 330; New Hygienic Society, 330 ; University Statistics, 374 St. Stefano, Earthquake at, 514 Salmon in Germany, 392 Salt, Ratton's Handbook of Common, 302 "Salzkammergut," Snow in the, 292 Sanderson (Prof. J. Burdon, F.R.S.), Bacteria, 84 Sanitary Institute, 38 Satellites, the, 129 Saunier's ".Modern Horology," 484 Saxony, Educational Statistics, 394 Schhemann (Dr. H.), Trojan Treasures, 132 ; "Mycenje," 397 ; " Troy and its Remains," 397 ; " Antiquities from Hissarlik," 397 Schmidt's Lunar Chart, 408 Schoolmasters, Congress of, in Paris, 314 Schuster (Dr. Arthur, F.R.S. ), VogeFs "Spectrum Analysis," 99 ; the Radiometer and its Lessons, 143 ; the Presence of Oxygen in the Sun, 148 Schwann (Theodore), Festival in Honour of, 436 Schweinfurth (Dr.), Proposed Return to Africa, 90 Science : Prof. Rudolf Virchow. on the Liberty of Science in the Modern State, 72, 92, ill; Science and Art Department Examinations, 134; Science in Training Colleges, 262; the Head-Masters on Science Teaching, Rev. W. Tuckwell, 317; Science at the Paris Exhibition, 357 Scientific Research, Grants of the British Medical Association, 90 Scientific Serials, a New Catalogue of, 272 Scientific Worthies, XII. — William Harvey ( With Portrait), 417 Scotland, Prof. J. W. Judd, F.R.S., on the Strata of the Western Coast and Islands of, 335 Nature, May 30, 1878] INDEX Xlll Scottish Meteorological Society, 440 Scottish Universities Commission, 441 Sea-Sediments, Movements of, 293 Sea-Water, Oxygen in, J. Y. Buchanan, 162 ; as a Specific, 234 Sccchi (Father), Illness of, 291 ; Death of, 350 ; Obituary Notice of, 370 Sediments in the Sea, Movements of, 293 " Seiches" on the Lake of Geneva, 234 ; and Earthquakes, Dr. F. A. Forel, 281 ; the Law of, 475 "Selborne," Prof. Bell's White's, 399 Selective Discrimination of Insects, 62, 163 Selenium, Action of Light on, Robert Sabine, 512 Scmirechensk District, Exploration of, 252 Sense in Insects, W. M. Gabb, 282 Sewing Machines, Effects from Using, 71 ; a New, 371 Sewage, the Metropolitan, 157 Seychelles and Mauritius, the Flora of, by J. G. Baker, 77 Shadows, Obsei-vations on, 351 Shells, Atlantic, WoUaston's 503 ; Dr. P. P. Carpenter's Col- lection of, 513 Shenstone {W. A.), Conservation of Energy — Lecture Experi- ment, 45 ' Shetland and Orkney, Glacial Geology of, S. Laing, M.P., 123 Shooting Stars, 201, 212 " Shorthand for General Use," Prof. Everett, 17 Shot, Trajectories of, Rev. Francis Bashforth, 401, 506 ; W. D. Niven, 466 Siberia : Sea Trade with, 324 ; the University of, 354 ; and Mongolia, Exploration of, 435 Sidebotham (Joseph), Singing Mice, 29 Silesian Society, Proceedings of, 219 Silver Salts, Relations between the Volumes of, 260 Simon Testimonial Fund, 371 " Simple Lessons for Home Use," 25 Singing in the Ears, Xenos Clark, 342 Singing Mice, 11, 29 Sipyhte, a New Mineral containing Niobium, 269 " Sizing of Cotton Goods," Thomson's, 4 Skin, Human, and Mineral Waters, 252 Skull, the Morphology of the, Parker and Bettany, 3 Slater (H. H.), Singing Mice, li Sleep, Causation of, 124 Smell and Hearing in Insects, Henry Cecil, 381 Smith (A. Percy), the Telephone, 380 Smith (George), Ancient History from the Monuments, 119 Smith (Worthington G.), a Fossil Fungus, 127; the Fossil Peronospora as a Primordial Plant, 144 Smith (Herbert H.), Exploration of Brazil, 308 Smith (J.), " Ferns, British and Foreign," 43 Smith (Prof. W. Robertson), the Colour Sense of the Greeks, ICX3 Smithsonian Institution : 18, 39 ; Annual Report, 192 Smyrna, Plague of Field-mice or Rats in, 43 Smyth (Prof. Piazzi), Sun-spots and Terrestrial Magnetism, 220 Snake Poison, 337 Snow in the " Salzkammergut," 292 Snowflakes, Hailstones, and Raindrops, the Formation of. Prof. Osborne Reynolds, F.R.S., 207 Soap-Films, the Acoustical Properties of, Prof. Silvanus P. Thompson, 486 Social Electrical Nerves, 305, 346 Societe des Colons Explorateurs, 290 Societe d'Hygiene of Paris, 310 Solar Corona, Early Observations of the, 14 Solar Eclipses : The Total Solar Eclipse of July 29, 1878, 36, 250, 269, 381, 452, 453; J. Norman Lockyer, F.R.S., on, 481, 501 ; Solar Echpse of a.d. 418, 163 Solar Radiation in India, Methods for Determining 131 Solar Spectrum, Optical Spectroscopy of the Red End of the, J. B. N. Hennessey, F.R.S., 28 Solar, see also Sun Soleil (M.), Death of, 455 Soles and Turbot, Consignment of, to America, 212, 311, Sorby (H. C, F.R.S.), the Colouring Matter of Human Hair, 355 Sound: Experiment on Viljralions, 194; "Lord Rayleigh's Theory of Sound," Prof. H, Ilelmholtz, F.R.S., 237 ; Velo- city of, 410 ; Sound Colour- Figures, Sedley Taylor, 426, 447 ; and Density, J. Cameron, 507 ; the Transmission of, l)y Wires, 519 Sounding Apparatus, Lieut. Theo. F. Jewell, 230 Spain, Science in, 91 ; the Telephone in, 437 Spalding, Douglas A,, Obituary Notice of, 35 Spanish Peninsula, the Climatology of the, 248 Spectroscope, the, and its Work, R. A. Proctor, 360 Spectroscopical Researches of D' Arrest, 311 " Spectrum Analysis," Vogel's, 99 Spherules, Coloured, in the Retina of Birds, 473 Spiders, Hungarian, 128; the Aeronautic Flight of, 434; Spider and the Wasp, 402, 448 Spitzbergen, Maps of, 290 vSponges, Glassy, 222 Standards, Public, at the Guildhall, 454 Stanley (H. M.), Exploration of Africa, '49, 90; at the Cajje, 109 ; his Arrival in England, 232, 249, 291 ; Dinner to, 270 ; at St. James's Hall, 297 ; his new Work on Africa, 364 Starch in Plants, 269 Starfishes, North American, Alex. Agassiz, 98 Stars : Tycho Brahe's, of 1572, 129 ; Variable, 163, 210, 231, 288; Shooting, 201, 212; e Indi, 231; the Star Lalande, 19,034, 306 ; Double, 407 Steam-Engine, a Remarkable Small, 214 Steel Plates, Gigantic, 436 Stellar Systems, 82 Stewart (Prof. Balfour, F.R.S.), Sun-spots and Declination Ranges, 326 Stobart (J. W. H.), Islam and its Founder, 239 Stockholm, the Royal Library at, 273 Stockdale (William), the Telephone, 380 Stokes (Prof, G. G., Sec. R.S.), Certain Movements of Radio- meters, 172, 234 Stone (Dr. W. H.), Grove's Dictionary of Music, 422 Stoney (G. Johnstone, F.R.S.), the Radiometer and its Lessons, 79, 181, 261 Stonyhiurst, Meteorology of, 489 Strassburg, New University Buildings, 55 ; University Intelli- gence, 195 ; Discovery of Prehistoric Remains in, 492 Strawberries in December, 193 Strontian, Lime, and Baryta, Crystallisation of, 372 Striimpell (Dr.), Causation of Sleep, 124 Strychnia and its Antidote, J. Sinclair Holden, 360 Styria, Avalanches in, 273 Subsidence of Soil in France, 513 Suicides in France, 54 Sumatra : Death of the Leader of the Dutch Expedition to, 170 ; Exploration of, 290, 409 Sun : the Sun's Distance, i ; the Sun's Photosphere, J. Norman Lockyer, F.R.S., 23 ; Sun's Magnetic Action at the Present Time, J. Allan Broun, F.R.S., 183 ; Photographs of the, 195 ; the Presence of Oxygen in the. Dr. Arthur Schuster, F.R.S., 148 ; R. Meldola, 161 ; Dr. Henry Draper, 339 ; Age of the, in Relation j to Evolution, 206, 303, 321, 360, 464 ; Age of the Sun's Heat in Relation to Geological Evidence, S. Tolver Preston, 423 Sun-spots : Rainfall in the Temperate Zone in Connection with the Sun-spot Cycle, Dr. W. W. Hunter, 59 ; Sun-spots and Terrestrial Magnetism, Prof. Piazzi Smyth, 220 ; A. W, Downing, 242; B. G. Jenkins, 259 ; J. Allan Broun, F.R.S. 262, 280 ; Joas Capello, 488 ; Sun-spots and Declination Ranges, Prof. Balfour Stewart, F.R.S., 326; Sun-spots and Rainfall, 61, 443, 448, 505 _ Supplementary Eyebrows, W. Ainslie Hollis, 124 Swinhoe (Robert, F.R.S.), Death of, 16; Obituary Notice of, 35 Sydney, International Exhibition at, 233 Sylt, the Island of, Discovery of a Submerged Village, 232 Sylvester (Prof. J. J., F.R.S.), Chemistiy and Algebra, 284, 309 Symons (G. J.), Alluard's Condensing Hygrometer, 28 Tacitus, the "Nerthus" of, 250 Tait (Prof. P. G.), " Sketch of Thermodynamics," Prof, Clerk Maxwell, F.R.S., 257, 278; ZoUner's Scientific Papers, 420; Thermal Conductivity, 480 Talking Machine, Edison's, 469 Tanner (Prof. H. W. Lloyd), Potential Energy, 81 Taschenberg (Dr. E.), Die Insekten, 41 Tasmania, 508 Taunton College School, 16, 154, 214, 354 Taylor (Sedley), Fluid Films, 44 ; Was Galileo Tortured ? 299 ; Phoneidoscopic Representation of Vowels and Diphthongs, 447 ; Sound Colour- Figures, 426, 447 XIV INDEX [Nature, May 30, 1878 Technical Education, Prof. Huxley on, 97 Technical University, the Proposed, 154 Teheran, Gold in, 115 Telegraphy : Telegraphic Warnings in Mines, 16 ; without Wires, 153; Telegraphs in Berlin, 251; the Society of Telegraphic Engineers, 277 ; Granfeld's Apparatus, 292 ; Social Electrical Nerves, 305, 346 ; and the Herring Fishery, 351 ; Telegraphic Warning Apparatus, 351 Telephone, the : 48, 135, 379 ; in Germany, 52, 71, 91 ; and the Post Office, 109 ; German Postal Regulations for, 131 ; Prof. Bell's Lecture on, 131 ; Telephonic Alarum, Dr. W. C. Rontgen, 164, 181 ; Experiments between Dublin and Holyhead, 170; Prof. Barrett on the, 193; James M. Romanis on a T>itw Form of, 201 ; Telephone without Magnetism, W. J. Millar, 242 ; its Use in Warfare, 25 1 ; Demonstration of Currents originated by the Voice in Bell's Telephone, ¥. J. M. Page, 283 ; Experiments with the, 292, 310, 342; W. 11. Preece on the, 295; W. Ack- royd on the Mechanism of, 330 ; the Telephone as an Instrument of Precision, Prof. Geo. Forbes, 343 ; Telegraphic Warning Apparatus, 351 ; and the Post Office, 352 ; and the Telegraph, 372 ; in China, 392 ; Action of the, on a Capillary Electrometer, 395 ; as a Means of Measuring the Speed of High Breaks, J. E. H. Gordon, 424 ; the Henry Telephone, 437 ; in Spain, 437 ; Application of, for Testing the Hearing, 475 ; Signalling by the, 491 ; a Mercury Tele- phone, 491 ; Early Electric Telephony, Prof. W. F. Barrett, Telescope, the Modern, J. Norman Lockyer, 66, 125, 188, 225 Tempel's Comet of Short Period, 408 Temperature ; Nocturnal Increase of, with Elevation, Dr. E. Bonavia, loi ; Average Annual, at Earth's Surface, D. Trail, 202; of November, 1877, 249; Temperatures, Cumu- lative, 308, 322, 448, 486 ; the Sense of, 372 ; Underground, Prof. J. D. Everett, 476 Tenby : Mr. Smith's Collection from the Caves, 212 ; Local Museum at, 391 Terrestrial Globe, a Self- Moving, 71 Terrestrial Magnetism, Prof. W. Le Roy Broun, 281 Terrestrial Magnetism and Sun-spots, Prof. Piazzi Smyth, 220 ; A.' W. Downing, 242 ; B. G. Jenkins, 259 ; J. Allan Broun, F.R.S., 262, 280; Joas Capello, 488 Texas, the Agricultural Ants of, 433 Thermal Conductivity, Prof. P. G. Tait, 480 Thermodynamics, on the Diffusion of Matter in Relation to the Second Law of, S, Tolver Preston, 31 "Thermodynamics," R. Wormell's, 25; Prof. Tait's, Prof. Clerk Maxwell, F.R.S., 257, 278 Thermopiles, Relative Value of, 437 Thierleben, Brehm's, 41 Thiers (M.), his Work on Trigonometry, 16 Thompson (Prof. Sylvanus P.), Faraday's "Experimental Researches," 304, 361 ; the Acoustical Properties of Soap- Films, 486 Thomson's " Sizing of Cotton Goods," 4 Thomson (J. Stuart), Mimicry in Birds, 361 .Thomson (Dr. Thomas, F.R.S.), Death of, 513 Thomson (Sir William, F.R.S.), Compass Adjustment in Iron Ships, 331, 352, 387 Thomson (Sir Wyville, F.R.S.), "The Voyage of the Challenger" — the Atlantic, 145, 185 Thorpe (Prof. T. E., F.R.S.), Note on the Liquefaction of Air, and of the so-called Permanent Gases, 384 Thunderstorms : the Law and Origin of, 362 ; in Iceland, 471; ; Artificial, 515 Thuret's Garden at Antibes, 351 Thyme and Marjoram, Fertilisation in, 127 Tibet, Notes on, 132 ; M. Prshvalsky's Exploration of, 153 Tides, High, Prediction of, 38, 45, 58, loi Titan, Transit of the Shadow of, across Saturn, 105 Toads, Change of Habits in, Wordsworth Donisthorpe, 242 Tomlmson (C, F.R.S.), Fluid Films, 61 ; Diffusion Figures in Liquids, 102 '^ Tomlinson (Herbert), the Telephone, 380 Tornado in Chester County, U.S., 362 Toronto, Earthquake near, 90 Torpedo Warfare, Modern, 50 Torpedoes, 361 Tortoises, Gigantic Land, Dr. Giinther, F.R.S., 483 Toucy, Belfry at, struck by Lightning, 392 Towering of Wounded Birds, Chas. Dixon, 45 Tracheal System, Palmen on the Morphology of the, 284, 340 Trail (D,), Average Annual Temperature at Earth's Surface, 202 Training Colleges, Science in, 262 Trajectories of Shot, Rev. Francis Bashforth, 401, 506 ; W. D. Niven, 466 Transatlantic Longitudes, J. E. Hilgard, 244 "Transcaucasia and Ararat," J. Bryce, 25 Transit Circle, the New, at the Paris Observatory, 165 Transit of Venus, English Report on, I ; French Reports of, 69 ; German Expedition, 392 ; the Transit of 1882, 507 Travel, Educational, 324 Trevelyan Rocker, Mechanical Analysis of the, Samuel H. Frisbee, 242 Tritoma, Bees Killed by, Alfred R. Wallace, 45 Trollope (Anthony), South Africa, 463 Troubitzkoy (Prince Pierre), Eucalyptus, 10 "Troy and its Remains," Dr. Schliemann's, 397 Trunk Engine, Batchelor's Patent Working Drawing of, 160 Tubingen, University Statistics, 354 Tuckey and Stanley — The Yallala Rapids on the Congo, Dr. J. Rae, 62 Tuckwell (Rev. W.), and Taunton School, 16; Presentation to, 214 ; the Headmasters on Science Teaching, 317 Tuning Foi-ks, Prof. McLeod's Experiments on, 55 Tunnel, the Proposed British Channel, 109 Tupman (Capt.), on the Meteor of December 6, 1877, 152 : the Great Detonating Meteor of November 23, 1877, 246 Turbot and Soles, Exportation to Massachupetts, 311 Turkoman Greyhounds, 434 Tycho Brahe's Star of 1572, 129 Tyndall (Dr., F.R.S.), Fog-signals, 456 Tyrol, Anthropology and Ethnology of South, 438 Underground Monster, a New, 325 Underground Railways in Paris, 492 Underground "J emperature, Prof. J. D. Everett, 476 United States : American Science, 18, 39 ; the Smithsonian Institution, 18, 39; the American Association for the Ad- vancement of Science, 37 ; Ethnology of the, 53 ; the Johns Hopkins Scientific Association, 113 ; Geological Work of the U.S. Survey under Prof. Hayden, during the Summer of 1877, 129; Lexington University, 175; Geological Survey of, 192; Proceedings of the American Philosophical Society, 199 ; Entomology in America, 229 ; Extension of Volun- teer Weather Service in the, 248 ; Tornado in Chester County, Penn., 362 ; Atlas of Colorado, 371 ; Prof. Hay- den's Expedition, 351; Harvard College Observatory, 363 ; the Geological Survey, 409 ; Cliff-dwellers in the, 409 ; American Chemical Society, 475 ; Survey of New York, 508 ; Proposed Catalogue of the Plants of North America, 514. See also America, New York, Philadelphia, &c. University and Educational Intelligence, 19, 39, 55, 74, 95, 114, 134. 154. 175. 194, 214, 23s, 254, 27s, 294, 314, 334, 354, 374» 393, 415, 459, 478, 497, Si7 University, Proposed New, 478 Upsala, University Statistics, 55, 478 Uranian Satellites, 323, 363 Variable Nebulje, 306 Variable Stars, 163, 210, 288; R Aquarii, 231 ; Pigott's Ob- servations of, 323 Valence or Atomicity, Discovery of the Law of, 309 Vaux (W. S. W.), the Greek Cities and Island of Asia Minor, Venus Transit, English Report on the, I ; French Reports of, 69 ; German Expedition, 392 ; the Transit of -1882, 507 Verne (Jules), the Works of, 197 Venezuela, Dr. Sachs on, 250 Vibrations, Experiments on, 194 Vibrations of a Flame, Experiments on, 54 Vibrations of Solid Bodies, M. Dubois on, 330 Vicars (G. Rayleigh), Acoustical Effects of Atmospheric Pressure, 244 Victoria Institute, 136, 216, 296, 416, 520 Vienna : University Intelligence, 55 ; Academy of Sciences, 116, 176, 196, 276, 296, 376, 500; Vienna Geographical Society, 211 ; Temperature of, 249; Society for the Protec- tion of Animals, 293 Nature, May 30, 1878] INDEX XV Vine-leaves, the Functions of, 20 Vines (S. H.), the First Stages of Development in Plants, 433 Virchow (Prof. Rudolf), the Liberty of Science in the Modern State, 72, 92, III Virginia Creeper, the Climbing of, 508 Viticultural Society at Cassel, 411 Vogel's "Spectrum Analysis," Dr. Arthur Schuster, 99 Vohl (Dr.), Method for Determining the Impurities of the Rhine, 131 Volcanoes: Volcanic Eruptions in Iceland, 171; Volcanic Island, 194 ; Volcanic Phenomena in Borneo, A. H. Everett, 200 ; Submarine, 372 ; in South America, 468 Volga and Moscow, Communication bet\veen,^9l Volta, the Statue of, 490 Volume of Liquids and Absorption of Gases, 514 Vowel Theory, Plelmholtz's, 41 1 Wallace (A. R.), and Reichenbach's Odyle, 8; Wm. B- Carpenter, F.R.S,, 8, 44 ; the Radiometer and its Lessons, 44 ; Bees Killed by Tritoma, 45 ; the Comparative Richness of Faunas and Floras tested Numerically, icx) ; Mr. Crookes and Eva Fay, loi ; Northern Affinities of Chilian Insects, 182 War, New Applications of Science to, 361 Warington (R.), Nitrification, 367 Wasp and the Spider, 402, 448 Watchman- Controlling Clock, 292 Water, Specific Heat of, 252 Waterfalls, Great, 221, 242 Waterspouts in Callao, 372 Watson (Arthur G.), Harrow School Bathing-Place, 487 Waugh (Gen. Sir Andrew Scott, F.R.S. ), Death of, 350 Waves, the Progression of, 95 Weather, Weekly Statistics of the, 489 Weber (Prof. Ernst Heinrich), Obituary Notice of, 286 Weights, Discovery of Ancient Bronze, 351 Wellington Philosophical Society, 296 West Indies, Higgins' "Notes on the Western Tropics," 121 Westinghouse Brake, 410, 507 Westminster Aquarium : 70, 193 ; Seals at the, 38 ; Laplanders at the, 70; Chimpanzee at, 153; Entomological Exhibition ^t, 351, 391, 402 ; American Fishes at the, 392 Whale, New Species of, 1 10 Wheel -Animalcules (Rotifers) of Hungary, 12S White Sea, Algae of the, 345 "White's Selborne," Prof. Bell's, 399 Whitmee (S. J.), the Southern Drought, 447, 486 Wild (M. H.), Researches on the Magnetic Properties of Nickel, 393 Williams (Prof. Monier), on Meteorology in India, 53 Williamson (Prof. W. C.), the Origin of a Limestone Rock, 265 Willmanns (Prof. Gustav), Death of, 436 Wilson (A. Stephen), the Earthworm in Relation to the Fertility of the Soil, 28 Wine Protection of France, 372 Wines, Adulteration of, in Berlin, 91 Winkler's Lunar Landscape, 469, 514 Wires, the Transmission of Sounds by, 519 Wisby, Discovery of Ancient Bronze Weights at, 351 Wisteria, the Seeding of, 439 Wojeikoff (Dr.), Travels in Japan, 171 Wolf (M. C), the New Paris Transit Circle, 165 Wolf's History of Astronomy, J. R. Hind, F.R.S., 259 ; (Trans- lation), 359 WoUaston (Thos. Vernon), Obituary Notice of, 210; "Coleop- tera Sanctse-Helense," E. C. Rye, 338 ; Testacea Atlantica, 503 Wolves in France, 233 Women, Higher Education of, 314; Prizes in Botany for, 314 Work, Relation of, and the Decomposition of Albumen, 515 Wormell (R.), " Thermodynamics," 25 Wright (Prof. E. Perceval), About Fishes' Tails, 286; the Islands of St. Paul and Amsterdam, 326 Wiirzburg, University Statistics, 334 Yallala Rapids on the Congo — Tuckey and Stanley, Dr. J. Rae, 62 Yenissei, Exploration of the, 38 Yorkshire College of Science, 175 Young (E. D.), "Nyassa," 99 Young (Frank W.), Cruelty to Animals' Act and Physiological Teaching, 45 Young (J.), Mimicry in Birds, 486 Zeitschrift fur wissenschaftliche Zoologie, 254, 479, 394 Zenger (Prof. Ch. V.), the Law and Origin of Thunderstorms, 362 Zeuthen (Dr. H. G.), Quatre Modele?, 240 Zollner's Scientific Papers, Prof. P. G. Tait, 420 Zoological Gardens, 68 Zoological Gardens : Additions to the, 18, 38, 54, 72, 92, no, 133, 154, 172, 194, 213, 234, 253, 273, 293, 311, 331, 352, 373, 411, 438, 456, 493, 515 ; Death of the Hippopotamus, 392 Zoological 'Society, 95, 115, 135, 170, 275, 355, 375, 460, 499, 520 Zoological Station, Naples, 329, 360 Zoological Station for the Channel Island;--, W. Saville Kent, 102 ; W. A. Lloyd, 143 Zurich, University Statistic;;, 374 A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE " To the solid grouna Of Nature trusts the mind which builds for aye." — WORDSWORTH THURSDAY, NOVEMBER i, 1877 TI/£ SUN'S DISTANCE A MO ST interesting state paper has just been issued ; we refer to the Report by the Astronomer- Royal on the Telescopic Observations of the Transit of Venus of 1874, made by the Expeditions sent out by the British Govern- ment and the results deduced from them. The Astro- nomer-Royal suggests that another report may be called for when the photographs of the transit have been com- pletely measured and worked out, if possible in combina- tion with the results of similar observations made in the expeditions organised by other governments. It will be seen from the present Report that the plan of operations actually pursued has been very nearly that proposed by the Astronomer- Royal in his communication to the Royal Astronomical Society on December 11, 1868, when for the third time directing attention to the arrange- ments which it would be necessary to make for the efficient observation of the transits of 1874 and 1882. The method of absolute longitudes was to be applied for observations both of ingress and egress ; it being therefore essential that the longitudes of the observing-stations should be determined with precision ; and the longitudes recommended to be fixed by Great Britain were Alex- andria, stations in New Zealand and in the Sandwich Islands, Kerguelen's Land, and Mauritius or the two islands of Rodriguez and Bourbon. The stations eventually selected for observations by the British expedition were fixed upon "entirely by considera- tion of the influence which their positions would have in determining with accuracy the necessary alteration of parallax." They were : Egypt, the Sandwich Islands, the Island of Rodriguez, New Zealand, and Kerguelen's Land. It was intended to adopt in each of these districts one fun- damental station, the longitude of which was to be inde- pendently determined, for conversion of local times into Greenwich times, and subordinate to thii primary station, other stations were proposed to be selected at such distances that advantage might be taken of different states of weather that might possibly prevail. In Egypt his Highness the Khedive rendered every Vol. xvii.— No. 418 possible assistance, tents being supplied with military guards for the protection of the observers and their in- struments, and telegraph wires erected. The Astronomer- Royal acknowledges the obligations of the expedition to the liberality of the Eastern Telegraph Company, in affording the means of determining with extreme ac- curacy and great facility the longitude of the principal station Mokattam. Greenwich was easily connected with Forth Curno, in Cornwall, whence there is an unin- terrupted line to Alexandria, the longest submarine line in the world ; Alexandria was connected with Mokattam by aid of the special line constructed by the Khedive from Cairo to the station. It is further stated that time- communication was also made from Mokattam through Cairo to Thebes, and to Suez by the ordinary telegraph, Thebes and Suez being the other Egyptian stations where the transit was observed. In the Sandwich Islands much assistance was received from King Kalakaua and members of the reigning family. The principal station was at Honolulu, the longitude of which was determined partly by meridian- transits of the moon and partly by transits of the moon observed with the Altazimuth instrument. Waimea, in the island Kauai, where observers were also placed, was connected with Honolulu by means of chronometers carried in H M.S. Teredos. At the Island of Rodriguez the longi- tudes were determined in the same manner as for the Sandwich Islands stations, for three positions, viz.. Point Venus, the Hermitage, and Point Coton ; and com- munication was further made with the Mauritius and with Lord Lindsay's expedition with the aid of H.M S Shear-water, the preliminary results being stated by Sir George Airy to agree closely with those given by the lunar observations. At Kerguelen's Land, again, the operations were similar ; Supply Bay and Thumb Peak being the stations chosen. In New Zealand unfavourable weather much interfered with the observations, and Sir George Airy had at first been led to suppose that all useful observation had been lost ; it subsequently appeared, however, that this was not the case, one phase of the transit being well seen at Burnham, the longitude of which was fixed by meridian transits of the moon. The Report is divided into three sections or tables. NATURE {Nov. I, 1877 In the first are given the descriptions of the various phe- nomena, in the words of the observers, with the Green- wich sidereal times of the different phases, obtained from accurate reduction of the ojjservatipns for longitude here particularised ; where such longitudes depend upon lunar observations the places of the Nautical Almanac were carefully corrected by observations on nearly the same days at Greenwich, Paris, Strasburg, and Konigsberg. In studying these original descriptions, Sir George Airy was led to infer that it was " possible to fix upon three distinct phases for the Ingress and four for the Egress," though it might have been supposed that Egress and Ingress would exhibit the same number of distinct phases in inverse order ; this was not the case in practice. The first phase, a, utilised in the calculations is the appear- ance of the planet just within the sun's disc, but the light between the two limbs being very obscure. After an interval of about twenty seconds " the light begins to clear, and the observers generally think that the contact is passed ;" this is phase /3. About twenty seconds later, the light which at phase /3 was not equal to that of the sun's limb, is free from all shadow, and the phase is called y. Sir George Airy finds that of these phases /3 is the most exact, observers, even in the presence of clouds of moderate density, agreeing within three or four seconds, though for other phases much greater discord- ances are exhibited. Similarly at the Egress, the first appearance of a fine line or faint shadow is called 8, this becoming definite, or a " brown haze " appearing, is called e. When most observers record "contact," the shadow having reached a maximum intensity, the phase is called f, and in this phase there is an agreement amongst observers, much closer than in other phases at Egress. The "circular" contact at Egress is called »;. In the second section of the Report, or Table II., these " adopted phases are massed for each district in which the parallax-factor is nearly identical," and several of the details of reduction are included. With the longitudes determined as above, the recorded times of the various phases of the transit were converted into Greenwich sidereal times. With the calculated apparent places of the sun and Venus in the Nautical Almanac, as deduced from Leverrier's Tables, an ephemeris was prepared ex- hibiting the predicted geocentric places for every tenth second of Greenwich sidereal time throughout the transit, and from these numbers the apparent positions of sun and planet at each station were computed. Calculations were further made, showing how the predicted places would be affected by alteration of the local longitude, by change in the tabular places of the sun and Venus, and by alteration of their tabular parallaxes ; the first two alterations were not essential in these reductions, but the determination of alterations of the third class, as it is remarked, constituted " the special object of the expe- dition." The form of the reductions was " entirely de- termined by the consideration that such alterations must be made in the parallaxes as will render the observations of the same phenomena in different parts of the earth consistent with each other." In Table III. we have " the mean solar parallax deduced from every available combination." Thus Ingress accelerated at the Sandwich Islands is compared with Ingress retarded at Rodriguez and with Ingress retarded at Kerguelen's Land ; Egress retarded at Mokattam and Suez with Egress retarded at Rodriguez, and likewise with Egress accelerated at the two stations in Kerguelen's ; and again the retarded Egress at Thebes is compared with Egress retarded at Rodriguez and with Egress accelerated at Kerguelen's. The greatest separate value of the solar parallax re- sulting from these different comparisons is 8'''"933 and the least 8""407. Weights are given to the various deter- minations depending, firstly, upon the number of observa- tions and the magnitude of the parallax-factor ; and secondly, upon the particular phase a, /3, ^y, S, e, and f being included. Thus it is found that all the combinations for Ingress give the mean solar parallax 8"739, weight io"46, and all the combinations for Egress give 8"'847, weight 2'53, whence the general result is 8"76o, from which Sir George Airy finds the mean distance of the sun equal to 93,300,000 miles. The New Zealand observa- tions were not included in these calculations ; their mean result is 8"'764, almost identical with the above. It is remarked that many persons may perhaps consider that the more closely-agreeing phases /3 and ^ should be em- ployed in deducing the value of the parallax to the exclusion of the others. If this be done we shall have from the Ingress 8"748, and from the Egress 8"*905, or with their due weights a mean value 8"773. In this outline of the details contained in the Astro- nomer-Royal's first Report upon the observations of the transit of Venus, and the conclusions to be drawn from them we have adhered closely to his own words. Pending the appearance of the deductions to be made from the complete measuring of the photographs, the results before us are perhaps to be regarded as provisional ones only, or we have not yet learned all that may be done from the work of .the British expeditions, so laboriously organised by Sir George Airy. Many astronomers we can imagine will regard with some 'suspicion so small a parallax as 8''76, which is a tenth of a second less than has been given by the most reliable previous investigations, upon different principles. In illustration we may quote the separate results from which Prof. Newcomb obtained his value of the parallax, now adopted in most of our ephemerides : — 8-855 8-842 8-838 8 •809 From meridian observations of Mars, 1862 From micrometric observations of Mars, 1862 From parallactic inequality of the moon From the lunar equation of the earth From the transit of Venus, 1769 (Powalky's reduc- tion) 8-86o , From Foucault's experiments on light 8 '860 To these may be added Leverrier's value subsequently deduced from the planetary theories, which is also 8"'86. Newcomb's mean figure, taking account of weights cor- respondirg to the probable errors is 8"'848, which, with ] Capt. Clarke's measure of the earth's equator, implies that the mean distance of the sun is 92,393,000 miles. Sir George Airy's 8 "760 would similarly place the sun at a mean distance of 93,321,000 miles. It is well known that some astronomers have not expected our knowledge of the sun's distance to be greatly improved from the observations of the transit of Venus, ^ regarding such an opportunity as is presented by a close | opposition of Mars as affording at least as favourable J conditions, [and the result of Mr. Gill's expedition to "Nov. I, 1877] NATURE Ascension to utilise the late opposition will be on this account awaited witli much interest. Nevertheless, what- ever degree of opinion might be entertained by competent authorities, it appears to have been felt by those imme- diately responsible for action, in different civilised nations where science is encouraged, that so rare a phenomenon as a transit of Venus could not be allowed to pass with- out every exertion being made to utilise it, and this country may lay claim to an honourable share in the great scientific effort, thanks mainly to the long-continued and admirably-directed endeavours of the Astronomer- Royal to secure this result. Several of the stations occupied during the transit of 1874 will be available for the transit of 1882, Kerguelen's Land in particular, where at Ingress the sun will be at an elevation of 12°, the factor of parallax being 0-98. In that year there will also be the advantage of observations along the whole Atlantic sea-board of the United States and Canada, where, as pointed out by the Astronomer- Royal in 1868, the lowest factor is 0-95, and the smallest altitude of the sun 12° for observing the retarded Ingress ; and for observing the Egress as accelerated by parallax, the factors are about 0-85, the sun's elevation varying from 4° at Halifax, to 32° at New Orleans, or Jamaica. Australian and New Zealand stations are important for retarded Egress. As is well known, the transit of Venus on December 6, 1 882, will be partly visible in this country. PARKER AND BETTANY'S "MORPHOLOGY OF THE SKULL" The Morphology of the Skull. By W. K, Parker, F.R.S., and G. T. Bettany, M.A. (London : Macmillan and Co., 1877.) IN the minds of most of those who have paid no special attention to the subject the skull is regarded as a bony case formed to contain the brain, together with the face. There is also a constancy in the number and posi- tion of these bones which lead to the apparently necessary conclusion that occipital, sphenoid, parietal, and other elements are fundamental cranial structures ; so that an exhaustive study of their relationships and variations might be thought entirely to cover the subject of skull structure. That such is not the case has dawned upon us since the elaborate researches of Rathke and other able em- bryologists, among the foremost of whom must be placed Profs. Huxley and Gegenbauer, who have been followed by Mr. Parker, the author of the work under consideration, who on account of his peculiar aptitude for manipulation, his untiring zeal and his immense experience, has placed the subject of cranial morphology upon a footing infinitely more satisfactory than it has previously been. His numerous memoirs in the Transactions of the Royal, Zoological, and Linnean Societies form a mine of biological facts, so beautifully supplemented by their accompanying illustrations. The perusal of them all, in their proper sequence, is however a task>nly to be undertaken by the specialist, and it is on this account that we have no small degree of pleasure in being able to give a notice of *' The Morphology of the Skull," a work of less than four hundred pages, in which is collected, condensed, and digested the mass of information spread through the larger memoirs. The work consists of a series of chapters on the skulls of carefully-selected types of the five classes of the Vertebrata. Those chosen are :— 1. The Dog-fish and Skate. 2. The Salmon. 3. The Axolotl. 4. The Frog. 5. The Common Snake. 6. The Fowl. 7. The Pig. These are each described in allj stages from their earliest appearance in the blastoderm to their adult con- dition. Following each chapter is a brief resuine of the peculiarities which have been observed in other members of each group, in such a manner that the student of any particular form can learn almost all he may require with reference to any special member of the sub-kingdom. The primitive trabeculas cranii, together with the para- chordal cartilages and the branchial arches are traced from their earliest development until ossification in and around them has reached the limits of the different types. The insufficiency of our data for the determination of the cranial segments is prominently brought forward, although the moniliform constrictions of the anterior extremity of the notochord in the fowl and in the urodeles is stated, and thought to suggest a segmentation. On the subject of the vertebral theory of the bony skull, Mr. Parker tells us that " only one bony segment, the occipital, can be said to be clearly manifest in the skulls of fishes and amphibians. And in these forms there are no good grounds for assigning to the cranial bones special names indicating a correspondence to particular parts of vertebras. From the study of adult structures in the mammalian groups skull-theories have been devised, lacking the basis of embryology ; and gi anting that they express some of the truth respecting the highest forms of skull, there is only injury to knowledge in arbitrarily interpreting the lower forms by them. In reptiles the skull becomes much more perfect, but with wide variations in the different groups, such that they cannot be merely subordinated to and explained by the mammalian type. A careful study of the growth of the bird's skull, again, will show that it is impossible to express its composition on a simple formula derived from vertebral structures. But from the lower to the higher forms of vertebrates we can discern a growing away from the primordial type of skull towards and into a loftier development." This result of the extensive investi- gation upon which it is based is somewhat paradoxical. The " loftier development " of the highest types results in a skull some of whose components may be compared in detail with some expression of truth to vertebra, whilst in the lower forms a similar comparison cannot be said to hold. And yet true vertebrae themselves, fully developed as far as their essential details are concerned, are found in forms far from high in the scale. Mr. Parker's invaluable investigations besides their importance in a comparative anatomical point of view, have done much to demonstrate the degree of stress which must be laid on facts of cranial structure in problems relating to classification. His labours have led him to elaborate the instructive classification of birds NATURE SJS^o'i). I, 1877 promulgated by Prof. Huxley in 1867, and so to bring out many points of special interest in avian cranial osteology, demonstrating most clearly the principle which may be arrived at from the study of any special organ or single structure, that a fact which is of the greatest significance in determining the relationships of some one collection of species or genera, may be valueless in attempting to classify others. As an instance of this we may take the skull of the woodpeckers and wrynecks, the peculiarities of which have led Mr. Parker to place them in a division by themselves of primary importance, whereas there is nothing more certain than that their differences from the Toucans and Capitonidas are only just sufificient to separate them as a family from either. And yet among almost all other orders of birds the cranial structure is invaluable in the determination of their affinities. The uniformity of the nomenclature and the absence of any laxity in the expression of the mutual relations of parts, greatly increases the facility with which the great number of facts brought forward by the authors can be grasped, and no doubt it is Mr. Bettany whom we have in great measure to thank for the general selection and classification of those which have been chosen to form "The Morphology of the Skull." In conclusion we feel certain that all who read the work under consideration, the very nature of which makes it almost impossible for us to discuss the details with refer- ence to any of the points which it brings forward, will realise how important an addition it is to biological science, and no thinking student will lay it down without recognising how much scope there is for still further investigation in the same field, especially in that direction which leads to the explanation of the reason why car- tilages grow and bones form in certain definite directions and situations and in them alone ; in other words, the next book of the kind required is one on the dynamics of the development of the skull. THOMSON'S "SIZING OF COTTON GOODS" The Sizing of Cotton Goods. By Wm. Thomson. (Man- chester : Palmer and Howe.) IN weaving cotton cloth it is necessary that the warp, which has to withstand a considerable strain in the process of manufacture, should be artificially strengthened by " sizing," that is, by dressing the thread with some adhesive material so as to enable it to resist the pulling and wearing action of the healds and shuttle. In the earlier days of cotton manufacture the weaver contented himself with the use of a mixture of flour-paste and tallow ; the first ingredient gave the thread the desired extra strength, the second removed the harshness which the use of flour alone would have given. But the manufacturer soon discovered that by a judicious selection of the components of his " size," and by alterations in the mode of applying it, he could confer upon the cloth the appearance of being fuller and stouter than it actually was, judging from the amount of cotton contained in it. The great scarcity of the raw material during the cotton famine which sprung out of the American civil war had a powerful effect in developing the ingenuity of a certain set of manufacturers, and there is no doubt that their machinations have had a lasting influence upon the mode of manufacture of grey cloth. As the weight of a piece of calico is one of the chief elements in determining its value, attempts were quickly made to increase that weight by mixing such bodies as powdered heavy-spar, or, worse still, of deli- quescent salts like the chlorides of magnesium and calcium, with the sizing material. Occasionally the manufacturer in thus attempting to palm off water or a worthless mineral in lieu of good cotton over-reached himself and a jusc retribution overtook him in the shape of heavy damages for mildewed or rotten goods. The results of many of these attempts afford excellent illustrations of the proverbial danger of a little knowledge ; the manufacturer somehow acquired the information that chloride of calcium, an almost worthless bye-product in many chemical operations, was an excellent absorbent of atmospheric moisture ; its advantages as an ingredient of the sizing mixture were therefore obvious ; unfortunately he knew nothing of oiditim oranteacnni or puccinia graminis, and had probably never heard of pencilium glaucum, or he might have known that he was preparing a mixture specially suited to the development of these fungi. Silicate of soda or water-glass doubtless appeared at first sight to be an excellent substance for dressing warp, but a painful experience was needed to teach some manufac- turers that these alkaline silicates rapidly absorb carbonic acid, and that the resultant products, namely, free silica, and sodium carbonate, together occupying a larger volume than the original silicate, exerted a disruptive action upon the hollow jCotton-fibre and made the cloth rotten and useless. Mr. Thomson does not altogether shirk the consideration of the moral aspects of the question of sizing ; he makes no secret of the fact that the operation is often done with fraudulent intention. He expresses his opinion distinctly enough that the introduction of an undue amount of size into goods intended for the home trade can serve no useful purpose, but we think he will find it difficult to convince ordinary or unbiased people that a composition consisting, to the extent of half its weight, of a mixture of putrid flour, or British gum, China clay, barytes, or magnesium chloride, tallow, or palm-oil, with a sufficient amount of chloride of zinc or carbolic acid to prevent the whole from running into absolute nastiness, is a fit material to clothe even the patient Hindoo or the prudent Chinaman. Mr. Thomson, how- ever, takes this business of sizing as a fact which, of course, cannot be ignored, and he tries to make the best of it. In the outset he shows that, as it now stands, the process is one of the clumsiest, most unscientific, and least understood of all the operations with which the manufacturer has to deal, and he points out, clearly and concisely, wherein it is faulty, and how it may be amended. The book is, of course, designed primarily for the use of grey-cloth manufacturers, calico-printers, and gene- rally of those whose business it is to buy and sell calico ; and the subject is mainly treated from the point of view of a chemist perfectly familiar with the objects sought to be gained by legitimate sizing. In plain and albeit scientific language he describes the various pieces of apparatus employed in ascertaining the value of the different ingredients in size ; he points out the qualities, good and bad, of the materials employed to give adhesive and softening qualities to the size ; how the Nov. I, 1877] NATURE size is to be applied to the yarn ; to what diseases or modes of decomposition it is liable ; and how it may be pre- served from mildew or mischievous changes. The book has every right to be regarded as the only important treatise on the subject which has yet appeared, and, as such, we would recommend it to all who are interested in the production of one of our chief staples. T. OUR BOOK SHELF Physiological Tables for the Use of Students. Compiled by Edward B. Aveling, D.Sc, F.L.S. (London: Hamilton, Adams, and Co.) We are at a loss to find any excuse for the publication of these tables, which no one, we presume, would attempt to justify except on the plea that they may be useful in cram- ming students so as to pass the multifarious superficial examinations which are a blot upon our educational system. They are unphilosophical in their plan, and altogether unreliable in their details. Some idea of the nature and value of the information which is here put up, as it were, into separate pigeon-holes for the use of the unwary, may be gathered from the following quotations. Nervous tissue, we are told, contains 15 per cent, of fats, thus classified : — Fats, 15 per cent, in white, ( Oleo-phosphoric acid. ^ ■" ^ V Olem ; margarm ; palmitm. ( Cholesterin. 5 per rent, in gray. Would Dr. Aveling like to write a short essay upon oleo-phosphoric acid 1 Has he never heard of such bodies as glycerin -phosphoric acid and its derivative lecithin ? Or to quote from Table IV., where Dr. Aveling writes on the causes of the circulation :— / Impulse of heart. Elasticity of arte- ries. c.-vuse.s of Circulation, Capillary Proofs. Force. Muscular pressure , on veins. 1. Alterations in diameter of cipil- liries. 2. Alterations of velocity of blood flowing through them 3. Movement of blood after excision of heart in cold-blooded amimals. 4. Emptying of arteries after death. 5 Secretion after death. 6. First movement of blood in em- bryo towards, not from, the heart. 7. Foetus without heart has organs developed. 8. Degeneration of heart during life without much alteration in the circulation. 9. Heart working well, and yet cir- culation through som; part ceases. 10, Asphyxia. Would it not be an admirable exercise to set the above hnes to intending candidates in physiology and ask them to criticise them 1 Our readers will do so for themselves. In the table referring to the sense organs we are con- fidently told that the nerve centres for the special sense of touch are the thalaini optici, that the centres of the special sense of smell are the olfactory lobes, that the centres of sight are the corpora quadrigemina, the corpora geniculata, and the thalami optici. But the above examples are more than sufficient to prove how dangero js a catalogue of mistakes Dr. Aveling has presented us with. If science is to be used as a discipline in education, let It be fully and accurately taught ; let us not imitate the old scholastic routine which forced unpalatable jargon in the form of "propria quae maribus," &c., upon the un- wilhng student, and refuse to follow it in that which is its merit— its accuracy. A. G. LETTERS TO THE EDITOR {The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he unda-take to return^ or to correspond with the writers of rejected manuscripts. No notice is. taken of anonymous communuations. The Editor urgently requests correspondents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of com- munications containing interesting and novel facts.] Indium in British Blendes It will be a matter of some interest to English mineralogists and chemists to know that certain blendes of Durham and, I believf , of Cumberland contain Indium in appreciable quantities. This fact has been made out by a very skilfully-conducted analysis by Dr. Flight in the laboratory attached to this department. The work in the laboratoy has, through the past two years, been almost exclusively devoted to the analysis of minerals selected from the division of the collection which is in process of being catalogued, and for which the crystallographic work has long been in progress. When I gave the particular blendes in question to Dr. Flight for analysis, the grounds for their selection were that they were British, and that one of them in particular resembled certain foreign blendes which contain the rare metals found in association with this mineral. The object of this letter is to secure a prompt announcement of Dr. Flight's having found Indium in the blende in question. He will in due time communicate further deta.ls of the analysis of the blende and of an elegant process by which he at once separates the Indium Sulphide from the blende. Nevil Story Maskelyne Mineral Department, British Museum, October 30 The Radiometer and its Lessons Will you allow me to make a few remarks in reply to to Dr. Carpenter's letter on " The Radiometer and its Lessons," pub- lished in the last number of Nature, and to try to show that I had good grounds for the opinion I expressed at the late meeting of the British Association in reference to his article on the same subject in the Nineteenth Century ? Nearly the whole of the first three columns of Dr. Carpenter's letter is devoted to proving that he " was not influenced, when writing on the radiometer, by any animus arising from [his] per- sonal antagonism to Mr. Crookes on another subject." As I never in any way charged him with being thus influenced, I do not think that this part of his letter calls for any further remark on my part than an expression of my sincere regret that it should have been possible for him to think that I intended to make such a charge. Dr. Carpenter devotes the rest of his letter to showing that he had "adequate justification" for "making it appear that Mr. Crookes had put a wrong interpretation on his own results," and thus proves very conclusively that I had " adequate justification " for supposing it possible that he may have intended to make this appear in his article in the Nineteenth Century. In order to make out his "justification," Dr. Carpenter sets himself to prove (i) that Mr. Crookes puts forward the " direct impact of the waves " as affording " a definite interpretation " of the motion of the radiometer, and (2) that he claimed "the discovery of a * new force ' or ' a new mode of force.' " With regard to the first of these points, I think that few per- sons can have read or heard Mr. Crookes's accounts of his investigations without having observed how careful he was to reserve his judgment as to the cause of the remarkable effects he had discovered, and neither to give out as conclusive any ex- planation of his own, nor to adopt any of those suggested by others until, chiefly through his own further experiments, one of them had been shown to rest on suflficient evidence. It is true that on one occasion he uses the following words (quoted by Dr. C rpentei) : — " My own impression is that the repulsion accom- panying radiation is directly due to the impact of the waves on the surface of the moving mass, and not secondarily through the intervention of air-currents, electricity, or evaporation and con- densation," and that, in several places in his earlier papers, he shows a leaning towards the same hypothesis ; but this is a very different thing from having adopted this view as a " definite interpretation" of the phenomena. Even Dr. Carpenter does not attempt to show that Mr. Crookes ever, in so many words, committed himself to this theory, but concludes that he held it NA TURE \_Nov. r, 1877 from considerations which, for fear of misrepresentation, I must give in Dr. Carpenter's own words : — " After pointing out that 'there is no real difference between heat and light, all we can take account of [I presume he means physically, not physiologically] being difference of wave-length,' he [Mr. CrookesJ thus continues : ' Take, for instance, a ray of definite refrangibility in the red. Falling on a thermometer it shows the action of heat ; on a thermopile it produces an electric current ; to the eye it appears as light and colour ; on, a photographic plate it causes chemical action ; and on the sus- pended pith i^rawj-^j w^/Zisw.' Now (i) this motion being else- where spoken of as due to the impetus given by a ray of light, (2) a set of experiments being made to determine the mechanical values of the different colours of the spectrum, (3) an observation being recoided on the weight of sunlight (without the least inti- mation that he was ' speaking figuratively ' as Mr. Crookes says that he did to his audience at the Royal Institution), (4) the term light-mill htvng used by himself as a synonym for 'radiometer,' and (5) no hint whatever being given of the dependence of the result (as argued by Prof. Osborne Reynolds) on a ' heat-reaction' through the residual vapour, I still hold myself fully justified in attributing to Mr. Crookes the doctrine of the direct mechanical action of light, " Taking these points in order and using Dr. Carpenter's numbers for reference, I may observe as to (i) that this seems to refer to Mr. Crookes's statement of an " impression " in a passage already quoted; with regard to (2) that Mr. Crookes having found that "every ray from the ultra-red to the ultra-violet " produced a mechanical effect under the circumstances of his experiments, it was very natural that he should hope to get some clue as to the nature of the action by finding what rays produced the greatest effect ; of Dr. Carpenter's arguments (3), (4), and (5), it is difficult to speak with the seriousness befitting their author's many valuable services to the cause of science, and the "due consideration of . . . his and my lelative positions." To conclude that Mr. Crookes must have held a particular theory from the fact that, when he had constructed an apparatus which spun round on exposure to light, he called it a "Light-mill ;" from his having neglected to give warning that he was " speaking figuratively " when he talked of "weighing a beam of sun-light," or from his having given no hint that he had adopted a rival theory, is certainly not to exemplify the " strict reasoning based on exact observation " which Dr. Carpenter recommends in the paragraph with which he concludes both his article and his letter to this Journal. A few sentences before the passage I have quoted. Dr. Carpenter refers to the "whole phraseology " of Mr. Crookes's papers of January 5 and February 5, 1876, as indicating "that he then considered [the motion of the radiometer] as directly due to the impact of the waves upon the surface of tl e moving mass." This again seems to me a very unsound conclusion. The effect to the elucidation of which these papers were devoted was un- questionably due to the incident radiation, but whether as a primary or as a secondary effect, was still a matter for discussion. In my opinion the phraseology used in them implies no more than this : it indicates a relation of cause and effect, but, for the most part, leaves the question as to how the latter follows from the former, entirely untouched. If, however. Dr. Carpenter will refer to § 195 of the paper of February 5, as it is printed in the Fhil. Trans, for 1876, he will see that Mr. Crookes did not then attribute the motion to direct impact of the rays upon the surface of the moving body, but rather to an elevation of its temperature, and a consequently increased radiation of heat from its surface. At the same time he will see that this suggestion is put forward in a tentative and entirely undogmatic way. Dr. Carpenter next undertakes to show that Mr. Crookes laid claim to the discovery of a " new force " or a "new mode of force," finding his proof of this in a passage included in the quotation from his letter that I have given above. Commenting on this passage in the Nineteenth Century (p. 248), he says : "To the //^r^^ attributes of radiation universally recognised by physicists, Mr. Crookes proposes (in the passage already cited) to add a fourth, the power of producing an electric current in a thermopile ; and a fifth, the power of producing mechanical motion when acting on light bodies freely suspended in a vacuum," Again, if Dr. Carpenter had consulted the Philo- sophical Transactions for 1876 (p. 361), he might have done Mr. Crookes more justice and might have given him credit for the discovery of a sixth attribute of radiation — (Mr. Crookes there mentions one more effect which the same ray can produce : "concentrate it on the hand by a lens, it raises a blister accom- panied with pain "), — and, if he had read a few lines further, he might have spared himself the trouble of explaining to Mr. Crookes that the electric current of a thermopile is not directly excited by the incident radiation, for he would have found that this action, in common with the pain and the blister and the motion of the mercury in a thermometer, is there spoken of as being an effect of heat. I think it must be evident to any one who will read this passage attentively with its context (either in Proc. Roy. Soc. [February 10, 1876], from which apparently Dr. Carpenter quotes, or in the Phil. Trans., loc. cit.), that it has nothing at all to do with either one or more new forces, but that the whole gist of it is to assert that, whatever may be the mode in which radiation produces mechanical force, the result is to be attributed to it as a whole and not to a particular constituent assumed for the purpose. As though with the object of covering a retreat, Dr. Carpenter says, near the end of his letter, that " Pi of. G. Carey Foster will doubtless be able to pick out points of detail in my article, as to which faults may be found by a severe critic." I may therefore point out that I have so far carefully confined myself to what he himself singles out as the "main issues" of the question between us, and that, in my further remarks, I shall treat the matter from a still more general point of view. In speaking (in my address at Plymouth) of the " tendency" of Dr. Carpenter's article, I meant to indicate that I referred in what I said about it to what seemed to me to be its general drift and tone, rather than to any particular passage or passages. And my judgment of the drift of the article was formed not only from what I found in it, but also from what I did not find there. For example, if Dr. Carpenter had thought as highly as I do of Mr. Crookes's work he would almost inevitably have pointed out more emphatically than he did the really astonishing number, variety, and laboriousness of his experiments ; he would also, I think, have pointed out that (with the important exception of Dr. Schuster) scarcely one of the numerous investigators, who, in consequence of his researches, have occupied themselves more or less with the radiometer, had obtained any significant experi- mental result which Mr. Crookes himself had not anticipated ; and he would have shown that the discovery of the radiometer, while affording a remarkable illustration of the importance ot following up unexplained though apparently trivial phenomena, illustrates no less forcibly the truth that scientific discoveries are not chance revelations, coming now to one and now to another, but that they are made only by those who have eyes to see a clue when it is offered them, and patience and skill to follow where it leads. Turning to what the article did contain, I think it is not incor- rect to say that it tended to produce the impression that Mr. Crookes, more or less obstinately, and on insuffici-^nt grounds, rejected a satisfactory explanation of his results. I will therefore try to state, as shortly as I can, what seems to me to be the true state of the case in relation to this point. Prof. Reynolds (in his paper read before the Royal Society on June 18, 1874) undoubtedly showed that a mechanical reaction, such as might account for the results obtained by Mr. Crookes, might arise when heat is communicated from a solid surface to a vapour or gas, but he did not (then at least) show that in Mr. Crookes's vacua there was enough residual gas to produce the results he ascribed to it. M'. Crookes, without disputing the possibility of the action pointed out by Prof. Reynolds, made experiments from which he concluded that it was insufficient to explain the movements he had observed. (I must here remark that Mr. Crookes did not say, as Dr. Carpenter asserts that he did, that the explanation offered by Prof. Reynolds was one that " it is impossible to conceive." His words were : "It is impossible to conceive that in these experiments sufficient condensable gas or vapour was present to produce the effects Prof. Osborne Reynolds ascribes to it. After the repeated heating to redness at the highest attainable exhaustion, it is diffi" cult to imagine that sufficient vapour cr gas should condense on the movable index to be instantly driven off by a ray of light, or even the warmth of the finger, with recoil enough to drive I ack- wards a heavy piece of metal." — Phil. Trans., 1875, p. 547. But although Prof. Reynolds is unquestionably entitled to the credit of having originated the fundamental idea and worked out many of the details of the explanation that seems now to be generally adopted, his explanation not only rested on a somewhat slender experimental basis, but was theoretically incomplete, and in par- ticular it did not show clearly why so high a degree of rare- faction should be needed for the production of the phenomena in question. An important step towards supplying this deficiency Nov. f, 1877] NATURE was taken by Profs. Tait and Dewar (July, 1875), who showed how the increase, resulting from rarefaction, in the mean length of the path of the gaseous molecules would favour the action, but the explanation in the form which they gave to it required that the rarefaction should be carried far enough to make the mean length of path of a molecule of gas great as compared with the dimensions of the inclosing vessel. It has, however, been pointed out by Prof. Zoilner {Pogq. Ann., February, 1877), and more recently by Mr. Tolver Preston {Phil. Mag., August, 1877), that, in ihe majority of cases, this condition is far from being fulfilled. On the other hand, the residual-gas theory of the action of the radiometer received very im- portant experimental support from Dr. Schuster's beautiful demonstration (February, 1876) that the force exerted on the discs was correlative with an equal opposite force exerted upon the glass envelope. The complete proof that the action was due in some way to the presence of residual gas was furnished by Mr. Crookes's own discovery (June, 1876) that it rapidly diminishes when the exhaustion is carried beyond a certain point depending on the nature of the gas. The outstanding defect in the theory was removed by Mr. Johnstone Stoney, who {Phil. Mag., March and April, 1876) showed that the observed pheno- mena might arise at a degree of rarefaction at v;hich the mean length ot path of a molecule was still much below the distance from the discs to the envelope, it being sufficient that this distance should not be too great to allow the warming of the discs to cause a sensible increase in the velocity with which the molecules struck the glass. Mr. Stoney's form of the theory answers to all the facts of the case, so far as I am acquainted with them, and it has been confirmed and illustrated by Mr. Crookes with a numerous series of remarkably beautiful and ingenious experiments. My object in thus tracing the chief stages in the growth of the accepted theoretical explanation of the radiometer has been to point out that the quality of mind which led Mr. Crookes to reject the various suggested explanations of the phenomena he had observed, so long as they were only approximate and did not account for all his facts, was merely a further exemplification of the quality which led him to the original discovery. If he had been content to disregard a seemingly trivial fact he would never have made this discovery at all, and if he had disregarded slight defects in the explanations that were offered he would have missed some of its most important consequences. I think that this also might have been suitably included among the "Lessons of the Radiometer." G. Carey Foster University College, London, October 27 Has Dr. Carpenter"allowed himself to become possessed by a "dominant idea?" From his letter in NATtJRE (vol. xvi. p. 544), I infer that he might have taken the trouble to reply to my article in the Ju'y number of the Nineteenth Century, had he not thought that my assertions " were well known in the scientific world to be inconsistent with fact." Some remark?, however, made by Prof. G. Carey Foster at the British Association seem to have forced upon Dr. Carpenter the conviction that he may have underrated my character /or veracity, and that the "scientific world," at all events, is not unanimous in regarding my "assertions" as falsehoods. Dr. Carpenter therefore seeks in your columns to justify the state- ments contained in his article on " The Radiometer and its Lessons," in the Nineteenth Century for April last. When Dr. Carpenter declares my "assertions (i) . . . (2) ... (3) " to be false, I have a right to demand that Dr. Carpenter give my identical words, and not his own interpre- tation of my words — an interpretation which is "inconsistent with fact." To show Dr. Carpenter's inaccuracies in small things as well as great, I may point out that he does not even quote correctly the title of my article in the Nineteenth Century. His carele.'s- ness in more important matter.i is of deeper consequence. In order to enforce one of his dominant ideas "yet more fully and emphatically," he tells us thit he applied himself to a "careful reperusal of" my papers " with the most earnest desire to present a true history of the whole mquiry." A most laud- able determination ! And where, will it be believed, did Dr. Carpenter, a Fellow of the Royal Society, go for information ? To the Philosophical Transactions, where my papers are printed at full length ? No ! He only referred to the " Proceedings of thd Royal Society," a record, as every one knows, that contains brief, and therefore imperfect abstracts of what is published in full in the Transactions. In his "justification" Dr. Carpenter quotes a passage from a lecture I delivered in 1874, on The Repulsion Accompanying Radiation, commencing, " my own impression is," &c. Had Dr. Carpenter quoted the next paragraph, which is necessary to a correct interpretation of the sentence he did quote, your readers would have been enabled to judge how far I advanced theories of my own. My words were these : " I do not wish to insist upon any theory of my own. . . . The one I advance is, to my mind, the most reasonable, and, as such, is useful as a working hypothesis, if the mind must have a theory to rest upon. Any theory will account for some facts, but only the true explanation will satisfy all the conditions of the problem, and this cannot be said of either of the theories I have already dis- cussea." My next paragraph concludes with the following quo- tation from Sir Humphry Davy: — "When I consider the variety of theories which may be formed on the slender founda- tion of one or two facts, 1 am convinced that it is the business of the true philosopher to avoid them altogether. It is more laborious to accumulate facts than to reason concerning them ; but one good experiment is of more value than the ingenuity of a brain like Newton's." With regard to my having " theorised on the subject," I have never denied having done so, although I have on five or six occasions specially stated that " I wished to keep free from theories," and " unfettered by the hasty adoption " of theories. But I do deny that I ever stated that my results were definitely explained by the direct mechanical action of light. Your readers will understand that an experimental research is necessarily and slowly progressive, and that the early provisional hypotheses have to be modified, and perhaps altogether abandoned, in deference to later observations. Until my experiments confirmed the explanation given by Mr, Johnstone Stoney, I adopted no definite theory, and I contend that a trained physicist would fail to gather from my published p)apers that I desired my first impressions to be regarded as final Dr. Carpenter again attributes to me the terms "anew force," or a "new mode of force," as applied to the repul>ion accom- panying radiation. Unless Dr. Carpenter can point these words out in my published papers, he has no right to place them between inverted commas. But the chief burden of Dr. Carpenter's song is that " Mr Crookes has another side to his mind, which mak'^s Mr. Crookes the spiritualist almost a different person from Mr. Crookes the physicist." I fail to see how the investigation of certain pheno- mena called spiritual can make a man a spiritualist, even if he comes to the conclusion that some of the phenomena are not due to fraud. My position in this matter was clearly stated some years ago, and I ask your permission to quote the following passages from an article I published in 1871 : — " I have desired to examine the phenomena from a point of view as strictly physical as their nature will permit. ... I wish to be considered in the position of an electrician at Valentia examining, by means of appropriate testing instruments, certain electrical currents and pulsations passing through the Atlantic cable ; independently of their causation, and ignoring whether these phenomena are pro- duced by imperfections in the testing ins'ruments them: elves, whether by earth currents or by faults in the insulation, or whether they are produced by an intelligent operator at the other end of the line." From this stand-point I have never deviated. Can Dr. Carpenter say that his position and mine, in respect to the investigation of the phenomena ascribed to spiritualism, are so very different ? He asserts that he has shown beyond doubt that it is all imposture. But I would ask if this was proved to his satisfaction twenty years ago, why does he still waste valuable time in interviews and sittings with so-called mediums ? If I am to be censured for having devoted time to this subject, such censure must be doubly applicable to a man who commenced the investigation when I was a child, and who cannot let the subject drop whenever a new " medium " comes in his way. Does he regard the subject as h's o^n special preserve, and may his demonstrations against other explorers in this domain of mystery be looked upon as the conduct of a gamekeeper towards a suspected poacher? To impress on the world that he has no " antmus," Dr. Car- penter says he " cordially" and " personally congratulated " me. His words bring vividly to my mind the conversation, of which, by the by, he has omitted an important part. It was at the annual dinner of the Fellows of the Royal Society on November 30, 1875, when the royal medal was awarded to me. Dr. Car- penter accosted me with great apparent cord-ality, and said. 8 NATURE {JSIgv. I, 1877 "Let us bury the hatchet ! Why should scientific men quarrel?" I signified my full acceptance of the offered peace, and great was my surprise soon afrer to find that, unmindful of the under- stood compact, he had exhumed his hatchet and was dealing me unexpected and wanton strokes, tempered by a certain amount of half praise which reminds me of the sort of caressing remonstrance of Majendie in the pre-ansesthetic days, to the dog which he had on his operating table — " Taisez votis, pauvre Mte!" In all seriousness, however, I must again ask, what is the meaning of the "personal antagonism," and the persistent attacks which Dr. Carpenter, for the last six years, has directed against me ? In his recently published book, in the Nineteenth Century, and in his last letter to you, the key-note struck in the Quarterly Rtviezv six years ago is sustained. We have the same personalities, the same somewhat stale remark about my double nature, a>^d the same exuberance of that most dangerous and misleading clnss of averments, half truths. Dr. Carpenter, indeed, condescends to admit that I have pursued "with rare ability and acuteness a delicate physical investigation in which nothing is taken for granted without proof satisfactory to others as well as to himself," and that I have "carried out a beautiful inquiry in a manner and spirit worthy of all admiration ; " but, after granting so much, he dissembles his love and proceeds to "kick me down stairs." I am damned with faint praise, and put to rights in such a school-masterly style, that I could almost fancy Dr. Carpenter carries a birch rod concealed in his coat-sleeve. He admits that in an humble and sub- ordinate sphere I have done useful work, only I must not give myself airs on that account. Dr. Carpenter reminds me of Dr. Johnson defending Sir John Hawkins, when he was accused of meanness. " I really believe him," said Johnson, " to be an honest man at the bottom ; but to be sure he is penurious, and he is mern, and it must be owned he has a degree of brutality, and a tendency to savageness, that cannot easily be defended." In the same magnanimous spirit Dr. Carpenter allows that I have contributed a trifle to science, but he does not forget to add that I am the victim of cerebral duplicity, and I am again held up to illustrate the sad result of neglecting to train and discipline "the whole mind during the period of its develop- ment," &c. & ^ r I have, it appears, two allotropic personalities, which I may designate, in chemical language, Ortho-Crookes and Pseudo- Crookes. The Ortho-Grookes, according to Dr. Carpenter, has acquired " deserved distinction as a chemist." He carries out a " beautiful inquiry in a manner and spirit worthy of all admira- tion." He has shown "ability, skill, perseverance, and freedom from prepossession." He pursues " with rare ability and astute- ness a delicate physical investigation." He evinces the "spirit of the true philosopher," and he has "deservedly" received "from the Royal Society the award of one of its chief dis- tinctions." But Pseudo-Crookes, whose career Dr. Carpenter has evidently watched almost from his cradle— as he professes to know the details of his early education— unfortunately took a "thoroughly unscientific course," and developed into a " specialist of specialists." He had "very limited opportunities " and " never had the privilege of associating" vrfth scientific men, al- though he displayed " malics aitimus" "towards those with whom he claims to be in fraternity." He is " totally desti- tute of any knowledge of chemical philosophy, and utterly untrustworthy as to any inquiry " not technical. His "asser- tions " are " well known in the scientific world to be inconsistent with fact." He enters on inquiries "with an avowed fore- gone conclusion of his own." He has " lent himself to the support of wicked frauds." He has "prepossessions upon which clever cheats play." His "scientific tests" are not "worthy of trust." He is a believer in "day dreams," and the supporter of a "seething mass of folly and imposture;" whi!st, to crown all, he actually thinks that the radiometer'is driven "by the direct impetus of light." In short, this Pseudo- Crookes is a compound of folly and knavery such as has rarely, if ever, previously been encountered. William Crookes (The Ortho-Crookes ?) London, October 29 Mr. Wallace and Reichenbach's Odyle I AM amazed that Dr. Carpenter should think it necessary to make public, with such haste, Prof. Hoffmann's statement that Baron Reichenbach's facts and theories are not accepted by the body of scientific men in Germany. Of course they are not. But how this affects their intrinsic accuracy I fail to see. Less than twenty years ago the scientific men of all Europe utterly disbelieved in the co- existence of man with extinct animals ; yet the facts adduced by Freere, Boue, McEnery, Godwin Austen, Vivian, and Boucher de Perthes, are now admitted to have been trustworthy and deserving of the most careful examuiation. The whole history of scientific discovery from Galvani and Harvey to Jenner and Franklin, teaches us, that every great advance in science has been rejected by the scientific men of the period, with an- amount of scepticism and bitterness directly proportioned to the novelty and importance of the new ideas suggested and the extent to which they run counter to received and cherished theories. Rejection is one thing, disproof is another ; and I have in vain searched for anything like disproof, or even rational explanation, of Reichenbach's facts : his theory, or " Odyle- doctrine," I have never "attempted to rehabilitate," as Dr. Carpenter, with his usual misconception, says I have done. In my review of Dr. Carpenter's lectures [Quarterly jFournal of Science, July, 1877, P- 39^)) I adduce five tests employed by Reichenbach, and also the independent and simultaneous con- firmation of Dr. Charpignon in France ; and the only reply I get is : "All men of science disbelieve them." With the facts of history above alluded to in my mind, and believing that human nature is very much the same in the nineteenth century as it was in the eighteenth, I can only say, " so much the worse for the men of science." Dr. Carpenter's reference to the believers in a flat earth, as a parallel case, is unfortunate, because the two cases are really of a totally different nature. Those who maintain the earth to be flat do not deny the main facts which we rely on as proving it to be round, but they attempt to give other explanations of them. The dispute is on a question of reason and inference ; and every intelligent and fairly educated man is able to decide it for him- self. But in Reichenbach's case it is the facts that are rejected without disproof or adequate explanation. The two cases are therefore quite distinct, and Dr. Carpenter's attempted parallel, as well as his setting up of scientific disbelief as a conclusive reply to evidence, is in conformity with his whole treatment of this subject. I trust that such of the readers of Nature as may feel any interest in the questions at issue between Dr. Carpenter and myself will read my article above referred to, and not allow themselves to be influenced by Dr. C.'s repeated appeals to authority and to prejudice. Alfred R. Wallace I HAVE to request your insertion of a post-card I have this morning received, for two reasons ; frst, because, as it is ano- nymous, and as the writer of it is obviously a reader of Nature, no otherway is open to me for replying to it except that which your columns may afford ; and secmidly, because it is a very curious' example of the misconceptions into which men are apt to fall who allow themselves to become " possessed " by " dominant- ideas." " If Mr. A. R. Wallace has to choose between being either 'a fool or a knave,' there is at all events no choice left for the man who deliberately and maliciously makes incorrect assertions and suppresses the truth to further his own views. I dare say you know what most people would call such a man. Yours, " One who was at Plymouth " Now, in the first case, it must be perfectly obvious to any one who is capable of reasoning logically, that nothing which I said of Mr. Wallace in your last number can be twisted into the implication that he is either " a fool or a knave." John Hampden is continu- ally saying this of Mr. Wallace and of everybody who upholds the rotundity of the earth. And I mildly suggested whether, in putting himself in opposition to the whole aggregate of scientific opinion on the value of Rf ichenbach's Odylism — not because he had himself repeated them, but because he believes in Reichen- bach— Mr. Wallace is not assuming an attitude in some degree similar, that is, setting himself up as the one wise and honest man who duly appreciates Reichenbach, and therefore implying that everybody else is either stupidly or wilfully blind to the evidence he presented. If anyone thinks it worth while to read Mr. Wallace's review of my lectures on "Mes- merism, Spiritualism," &c., in the last number of the Quarterly Journal of Science, he will be able to judge whether I have or have not wronged Mr. Wallace in this matter. The writer's appreciation of my own character, which has fre- Nov. I, 1877] NATURE 9 quently been expressed to me before in the same manner and in the like terse and elegant language, is now enforced by what he deems to be Prof. Carey Foster's judicial opinion, delivered at the Plymouth meeting ; and I find myself, therefore, fully jtisti- fied in my opinion that by his introduction of the word '* inten- tionally " Prof. Carey Foster made his judgment legitimately bear a meaning, which, as he has stated, he would consider insulting to my character. And I cannot but believe that Prof. G. Carey Foster will regret having thus given a new handle to a man who obviously wishes to insult me on account of my antagonism to spiritualism. As the writer of the post- card continues to use Prof. G. C. Foster's authority, after that gentle- man's explicit disavowal of the offensive meaning here attached to it, and as I may, of course, expect that he will continue to avail himself of that authority, I should like him to know through your columns that it is scarcely worth while for him to trouble himself to repeat these attacks, since they have long since ceased to do anything else than amuse me, and will only furnish me with materials for amusing other people. It seems much to be regretted that neither spiritualism nor attendance at the meetings of the British Association, nor even the reading of Nature seems able to teach this person to behave like a gentleman. WiLLiAM B. Carpenter October 29 Potential Energy Your correspondent '* X." has described some of his troubles respecting potential energy. Many a learner could describe similar troubles respecting force and energy in general. They who earnestly contend for definiteness and accuracy do not always teach with definiteness and accuracy. For example : in his "Treatise on Heat," p. 137, Dr. Tyndall tells me that by raising a weight from the floor I have conferred upon the weight potential energy. Presently he tells me that this energy is derived (not from me, but) from the pull of gravity. He next tells me that we might call the energy with which the weight descends, moving force, i.e. he teaches me to confuse force and energy ; and after all this he bids me remember that " exactness is here essential. We must not now tolerate vagueness in our conceptions." Take another example. In his lecture on " Force " (Nature, vol. xiv. p. 462), Prof. Tait teaches that force is a mere name, and that it has no objective existence ; he also teaches that the product of this non-existence by its displacement has an objective existence. Few learners would say that is a very lucid state- ment. Again, in the same lecture he says "there is no such thing as centrifugal force, and accelerating force is not a physical idea at all ; " but in his " Nat. Phil." he speaks of both these forces, and describes their effects (Nos. 185, 187, 598, 248). When teachers deservedly eminent make statements like' the foregoing, so likely to mystify and confuse a novice, it is no wonder that there is a good deal of smattering in popular science. Prof. Tait says " the so-called accelerating force is really no force at all, but another name for the kinematical quantity accele- ration." I venture to entirely disagree with this statement, and for the following reason : — — — is a number, and may be that number of units oi force, or that number of units of acceleration. When it is called accelerating force it is the representative of fn — , when m = i, and m does not appear in the expression ; c^ t' dv and it means - — units oi force. d t ^ it means — ^ units of acceleration, d t When it is called acceleration Accelerating force is just as real as moving force, for- it is, in fact, the wth part of the moving force. In like manner v may mean either v units of velocity, or v units of momentum ; in the latter case it is the representative of mv, when w = i, and means the momentum of a unit of mass which has v units of velocity. In like manner VI may mean either m units of mass, or m units of momentum, or m units of kinetic energy ; in the two latter cases it is the representative of mv or of fwz/' when v — \, and means the momentum, or the vis viva of m units of mass moving with unit of velocity. A few simple definitions would remove the difficulties re- pecting force. Thus : If a mass of m un'ts of mass is at any instant receiving an acceleration of a units of acceleration in any given direction, the force which is acting on it at the given instant in the given direction is ma units of force. The force acting on the mass in the direction of its motion is called the moving force. The force in the normal to the direction of its motion and towards the centre of curvature is called the centripetal force. An» equal and opposite force is called the centrifugal force. The mih. part of the moving force is called the accelerating force, which is the moving force acting on a unit of mass. In the case of a planet's orbit it is too common to give the name centrifugal force to two forces which generally differ both in magnitude and in direction, one of them being in the direction of the normal, the other in the direction of the radius-vector. This is the last instance which I shall give of sins against definiteness and accuracy. E. G. Bardsea ' Hartlaub's "Birds of Madagascar" The excellent review, exhibiting traces of a master's hand, of the above-named useful work, which appeared in Nature (vol, xvi. p. 498) prompts me to offer some remarks on the orni- thology of Madagascar and its neighbouring islands, and to take exception on two points therein laid down. The first of these is propounded by your reviewer and seems to me absolutely contrary to fact. He says :— " Compared with Madagascar itself the appendent island groups ' are poor in species, although in every case there are many interesting forms among their winged inhabitants. The Comoro Islands muster only some forty-four species of birds, Mauritius about sixty, of which fifteen or sixteen have been introduced by man's agency, and Bourbon about the same number, while Rodriguez appears to have only about twenty-five species now existing in it, of which four or five are certainly recent introductions." Now twenty years ago my friend, Mr. Sclater, in that remarkable paper of his on the geographical distribution of birds {y^mrn. Linn. Sac. Zoology, ii. p. 130), which so happily laid the tiue foundation for our present researches into the subject, showed that the proper mode of comparing the wealth or poverty of one fauna with another was to state the proportion which the number of species composing it bears to the area over which they range. The same view was adopted very shoitly after by Mr. Wallace, who took occasion (Idis, 1859, p. 449) to question certain of Mr. Sclater's results, and its correctness seems to have been since generally admitted. Yet, applying this test to Madaga9car and its neighbouring islands, we find a state of things to exist very different from that which your reviewer has alleged. The area of Madagascar is said^ to be 10,751 German square miles, that of the Comoros collectively 38 '57, of Mauritius 3476, of Bourbon 42*05, and of Rodriguez 5. It will be sufficient for my purpose to compare the first and last of these. Your reviewer is willing to allow twenty indigenous species to Rodriguez ; then — Area of Rodriguez. 5 Area of Madagascar. 10,751 : _ 10,751 X20 Species in Rodriguez. 20 • 43.004- Sp-cies in Madagascar. : X But instead of an avifauna of 43,004 species, or about four times the number known to exist throughout the whole world. Dr. Hartlaub gives it 218, and your reviewer generously adds two more, making 220 ! Suppose (an extravagant supposition) that future explorations enable us to double the last number, it is Madagascar that will still be out of all proportion " poor in species" compared with "the appendent island groups," and not these with Madagascar. The next point to which I must demur is that "the indi- viduality of the fauna of Madagascar is so unique that even that of New Zealand can hardly be compared with it." I will leave to fitter hands than mine to show that this is not the case gene- rally, and shall only remark here that it is not so with birds. Of the sub-class Ratita there have been until lately five strongly- marked groups, each of which is equivalent to an " order " amon^ the Carinatce. Now two of these groups were peculiar to New Zealand, and one (Apterygida;) is so now, while the other (containing the families Dinornithidce and Palapterygidce) is but recently extinct. Willingly granting that ^pyornis, when we ' Behin"und Wagner, "Arealund Bevolkerung der Erde" (Petennaon's Geogr. Mittheilungen, Erganzungsheft, November 10, 1876). Ba lO NATURE [Nov. I, 187; know more about it, may prove to form a sixth group, the balance of "individuality," if I understand the meaning of the word, will still be on the side of New Zealand. Turn-iig to the Carinate birds, Harpagornis stands alone, while Cnemiornis will certainly count for as much as the DididcE. The extraordi- nary Mascarene Rails {Miserythrus and Aphanapteryx) are well represented by Ocydromus, Tvhich so much resembles them, and Strigops is undoubtedly a more abnormal form than, so far as we can judge, either Lophopsittacus or Nicropsitlacus ; just as N'estor is more aberrant than Coracopsis, and Heterolocha than either Fregiluptis or Necropsar. But there is no need to con- tinue the list, and in conclusion I will only declare that I think far too highly of the fauna of Madagascar and of the Mascarene Islands to wish that its extraordinary peculiarities should be undervalued, though I do not want them to be unduly magnified £t the expense of those of the fauna of New Zealand. Alfred Newton Magdalene College, Cambridge, October 27 Eucalyptus Having read with great interest the article in your journal (vol. xvi. p. 443) on the Eucalyptus I take the liberty of sending you a pamphlet on the same subject, in which I have endeavoured 1 o unite all the arguments likely to persuade and convince the Italians of the immense utility of the above-named tree, the cultivation of which would be of the greatest importance for the Agro Romano. - As is well remarked in the article in Nature, the Eucalyptus is extensively cuUivated in France, Spain, and Portugal. But in Italy, where it prospers almost all over the country and might be cultivated with facility, in spite of the most earnest efforts on my part during my residence here for the last ten years, in spite of its being recommended in Parliament by one of the most influential members, it has not been adopted. In my gardens on the Lake Maggiore, I cultivate forty different varieties of the Eucalyptus. Of these the aviygdalina and the globulus have attained, in eight years, the height of 17 metres. It is to be remembered that the temperature has sometimes been as low as 7° C. below zero without injury to these plants. If you consider it probable that these few words could be ©f interest to your readers I willing authorise you to publish them in your estimable journal. Prince Pierre Troubitzkoy Villa Troubitzkoy, near Intra, Lago Maggiore, October 15 These trees are now attracting so much attention that even the small amount of experience I may be able to offer may not be unacceptable to your readers. Considerable stress is laid upon their influence in dissipating malaria ; but I have not found this to be the case in Queensland, one of the head-quarters of the tree. I have personally suffered from malaria in the very heart of a forest extending for many miles in every direction, and com- posed mainly of all the varieties of Eticalyptus, and not by any means remarkable for the extent of swampy ground, and have known many instances of febrile attacks among shepherds and stockmen in the locality. Moreover I was told on inquiry that these attacks were not confined to any particular year, but that every year some cases might be expected, I was greatly surprised at reading in your "Notes " (Nature, vol. xvi. p. 557) that the mosquitoes had disappeared with the introduction of the " gum" trees into Algeria. This would not be the experience of any one who has lived in Australia, I believe. I have found these pests so intolerable on high land, where almost the only tree to be found was one variety or other of Eucalyptus, and sometimes all, that sleep was impossible while camping out at night, and hfe a burden in the day by reason of these pests. The gums emit a most decided odour, especially in strong sun- light. "When riding across the great Queensland plains and approachmg wooded spurs I have (Scottice) " felt " the charac- teristic smell of the gums at a considerable distance. These plains— ten miles in breadth— are not crossed in a short time, and the resinous odour of the gums, omnipresent in the forest and scarcely noticed there, strikes one forcibly when approach- ing the trees after the olfactory organs have been for some time deprived of it Whether this odour has any effect or whether it is the preservative against malaria, I do not know. The growth of these trees in South America is very rapid. When in the Band a Oriental some years ago I examined a plantation of led and blue gums, then eight years old. The trees were at least forty feet high, and many of them measured thirty-six inches in circumference at three feet from the ground. They had a profusion of foliage such as I have never seen on the same trees in Australia. This was right out on " pampa " land, in deep alluvial soil. These trees had fought their way up, in spite of the black ants so destructive to foliage — the owner told me that they had at first stripped the young trees — and the tre- mendous gales which sweep over this open country. Those to the westward and south-westward of the plantation were far inferior in size to those on the east and north. This was the only grove of Eucalypti in the Banda, and it demonstrates the possibility of covering the naked pampas to any extent with forest. English settlers in the River Plate countries should note this fact, and I am sure the enlightened owner of the Estancia " Sherenden " would supply any of his countrymen with seed. Arthur Nicols Meteor of October 19, 6.15 p.m. The large meteor described by two correspondents (Nature, vol. xvi. p. 551) was observed also by several persons in this district, but most of the accounts are so meagre and doubtful as to possess little scientific value. The meteor appears, however, to have been well seen by Mr. W. Watkins Old, of The Parade, Monmouth, and his notes are so interesting that I beg to tran- scribe them. He says : — "The meteor fell at 6.15 exactly. It appeared to me to descend perpendicularly some degrees from and to the west of Arcturus (which was shining brightly), and it disappeared behind a bank of dark cloud above the horizon at a point in a line pro- jected beyond Arcturus, half the distance between that star and ihe last of those in the tail of Ursa Major, as roughly shown in the diagram below : — Ursa Major. ■ Arcturus. V Thus it remained stationary, like a dazzling white «'and, while I counted twenty, during which time I could perceive the vapour, of which the trail was composed, as it were in ebullition. It then gradually curved towards the north as depicted in the following sketch ; and drifted slowly away during eight minutes, oArctiirixs ^Arcturus until it lay almost horizontal though still brightly illuminated, while the clouds gradually rose and covered it from my view. Altogether I observed it over eight minutes by my watch. There was much twilight in the west and the moon was shining brightly from which one may judge the extreme brilliancy of the meteor. I should add that when it appeared there was simultaneously a sensible rent or flip, like one sometimes hears with a sharp flash of lightning, and which may possibly be due to the appulse of light, as it could scarcely be the sound of explosion if there was any. It was too simultaneous to be the report of the descent of the meteor through the air, but it was sufficiently loud to be pronounced and caused some people standing near me, with their backs to the west, to inquire what it was, though they evidently saw nothing of the meteor nor even turned towards its direction. I listened but heard no further sound." Ashleydown, Bristol, October 26 W. F. Denning Curious Phenomenon during the Late Gale Your correspondent, "G. A. M." (vol. xvi. p. 551), may be interested to know that the " ball of fire " he saw descend on the evening of the 14th inst. was seen here by me, and by those who accompanied me, at precisely the same time (6.50 p.m.) that he mentions. We were walking in a south-easterly direc- tion, and it seemed to fall from about half-way between that point of the compass and the moon, which was due south of us, and shining brightly. The ball itself appeared to us luminous white, while the " wake " left in its passage through the air, was bluish green. It was visible, I should say, for twenty seconds. Nov, I, 1877] NATURE 1 1 Occurring, as it did, at a time when thousands were wending their way to church, it must have been very generally observed. Harrow, October 26 A. W. B. J. Singing Mice When at school a friend and I used to keep tame mice, and amongst our large stock was one of the so-called singing mice. The mouse in question was not one we bred ourselves, but was bought from a London dealer, so we had no opportunities of knowing whether it had ever been kept near a singing bird or not J but it was not at all averse to performing in broad day- light, and would chirp whilst a knot of boys were standing round it as freely as when the cupboard was closed. As M. Brierre describes it (vol. xvi. p. 558), the mouse used to sit with its snout more or less elevated, but not at all to an uncomfortable height, and its throat used to throb like that of a bird whilst singing, the far of the one being ruffled like the feathers of the other ; and the song was something between that of a wren and that of a shrew mouse, and rather pleasing than otherwise. At first we were inclined to attribute the noise to disease of the lungs or throat, but were unable to hold that opinion long, as there never seemed to be any pain or gasping connected with it, but the noise was always produced at periods of greatest rest, and chiefly when the mouse came out of its sleeping place to wash its face and paws, at which times it generally chirped at inteivals. It never had the power of imparting the art to others, nor did any of its numerous progeny inherit its powers. Neither was it all short lived, but rather the contrary, and its death was caused by an accident. We were unable to consider the power of emitting the sounds at all the result of weakness or disease. Henry H. Slater Sound-Producing Arthropods I HAVE read with much interest the brief abstract given in Nature (vol. xvi. p. 567) of Mr. Wood Mason's announce- ment to the Entomological Society of the discovery of stridulating organs in association with scorpions ; reference being made at the same time to his recognition of similar sound-producing .'•tructures among other Arthropoda, including certain Crustacea. In this latter case no mention is made of the particular types with which these sound-organs have been observed, and I therefore hazard the relation of an instance that has recently fallen under my own observation with the chance of its proving a newly- recorded example. The crustacean in question, which I have ascertained to possess sound-producing properties to an eminent degree, is a species of Spherovia, belonging to the Isopodous order of the class. I have not as yet ascertained the exact method in which sound is pro- duced nor whether the animal has organs specially adapted for the purpose ; on numerous occasions, however, my attention has been attracted to the glass jar of which, with the exception of microscopic Copepods and Protozoa, a single specimen of the species is the sole animal occupant, by a little sharp tapping sound produced three or four times consecutively with intervals of about one second's duration, and which I can almost exactly imitate by gently striking the side of the jar witti the pointed end of a pipette. On being approached the little creature always endeavours to elude notice by passing to the opposite side of the stalk of seaweed, upon which it usually reposes in the same way that a squirrel dodges round the branch of a tree, and on no occasion so far have I been able to catch the little fellow flagrante delicto, or in the act of producing the sound which it most undoubtedly emits. The character and intensity of the sound produced associated with the small size of the animal, scarcely one quarter of an inch in length, induces me to believe that it is caused by the sudden flexion and extension of the creature's body. A more prolonged observation will no doubt clear up this point, but Mr. Wood Mason may possibly be in a position to throw further light upon the subject by means of the evidence he has collected hi reference to other crustacean types. Among the higher Decapodous crustacean order one species, Alpheus ruber, frequently collected by me in Guernsey, produces a snapping noise beneath the water by the sudden extension of the terminal joint of its larger claw that can be heard at a con- siderable distance, and that at once betrays its lurking place to a practised ear. The large sea crayfish {Palinurus quadricornis) agam, often emits when handled what may be filly described as a shrill squeaking sound by the rubbing to,^ether of the spinous ! abdominal segments. It would seem indeed that a closer study of the life habits of the aquatic Arthropoda is hkely to reveal among its members as infinite a variety of sound-producers as has hitherto been determined to exist among their more familiar terrestrial congeners. W. Saville Kent St. Heliers, Jersey, October 27 Insects and Flowers In reference to the question whether insects are most attracted to flowers by scent or colour, may I mention that while staying at the hotel at Cettinge lately I was amused by the behaviour of some humming-bird sphinx moths. My room was roughly stencilled with a "spotty" pattern of purplish brown on the dull white plaster. Every morning these moths, with their probosces extended, used toattack the dabsof colour, hovering before therr, just as though they were real flowers, but starting back with apparent amazement on finding that they were not. This seems the more remarkable because the wonderfully abundant aro- matic herbs of that region, which must have supplied their usual food, have all, so far as I know, very inconspicuous flowers Notting Hill, October 27 A. J. H. FRANCIS VON ROSTHORN PRANCIS VON ROSTHORN, who died June 17, ^ 1877, was the son of Matthew Rosthorn, of Lancashire, who went to Vienna in 1765, at the invita- tion of the Empress Maria Theresa, to establish the manufacture of metal buttons. He constructed the first rolling-mills in Austria ; one at Vienna, another (in 1792) at Fahrafeld, in Lower Austria. Matthew von Rosthorn was ennobled by the Emperor Joseph II. in 1790, and died at Vienna January 3, 1805, leaving five sons. The youngest of these, born April 18, 1796, at Vienna, is the subject of this notice. These five brothers joined in creating extensive metallurgic establishments ; the first (1817J at Oedj and another (1823) in Carinthia, for smelting zinc (then high in price) out of the Raibl and Bleyberg ores, by means of brown coal. Having pur- chased (1826) the state demesne of Wolfsberg, in Carinthia, with extensive metallurgical works, they con- structed there a large rolling-mill, together with a puddling furnace. Francis von Rosthorn, having prepared him- self for his practical career by attending the Mining Academy of Schemnitz, in Hungary (1814 to 1818), soon became acquainted with several eminent geologists, and obtained the patronage of the late Archduke John. He made several scientific tours in Carinthia, Carniolia, Styria, Salzburg, and the Hungarian border; in 1827 with Prof. Keferstein, in 1828 with Archduke John, in 1829 with Escher and Schrotter, and in 1832 with Dr. Boud. His annual visits to Archduke John at Gastein (1829 to 1836) were always connected with Alpine explo- ration. His later travels (1842 to 1847) were chiefly southward. In 1832 he communicated the results thus obtained to the Meeting of German Naturalists at Vienna ; and in 1836 to the meeting at Freiburg. In 1848 he was elected into the Legislative Assembly ("Landtag") of Carinthia ; and from 1852 to 1870 held the office of President of the Commercial and Industrial Board of that province. Francis von Rosthorn's constitution was exceptionally robust, so that up to his seventy-sixth year he was able to undertake arduous Alpine ascents. His conversation with persons of any social station was unaffectedly amiable ; but he could be sarcastic when he met with affectation or baseless pretensions. SPECTRUM OF AURORA AUSTRALIS AS I believe no account of spectroscopic observations of the Aurora Australis have as yet been published, I venture to send this description of two aurorae observed during the stay of H.M.S. Chaltenger in high southern ' Obituary Notice by Prof. E. Suess (" Report of the Imperial Geological Institute, Vienna/' August si> 1877). 12 NATURE [Nov. I, 1877 latitudes. The opportunities of observing were not frequent, either from the rarity of the phenomena (which is very possible) or because the dense mass of cloud which is the prevailing feature of those regions prevented their being seen except when exceptionally bright. Altogether four appearances were noted. The first was 1.30 on the morning of February 9, 1874, in lat. 57° S. and long. 75° E., bar. 29-0 in., ther. 35°. There were brilliant streaks to the westward ; no spectroscopic obser- vations were taken. The second was on February 21 at 9.30 P.M., lat. 64° S., long. 89" E., bar. 28 8, ther. 31° ; one bright white curved streamer extended from Jupiter, which appeared to be near the focus, through Orion and about as far beyond. Under this was what appeared to be a black cloud, but the stars were visible through it. Real cumulus clouds hid great part of the remainder, but there were two vertical flashing rays that moved slowly to the right (west), generally the aurora was still and bright. On examining the streamer with the spectroscope I found the usual three prominent lines, namely, one yellow- green, one green, the third blue or purple. I looked for the red line but could not find it. The third aurora was seen on March 3, lat. 53° 30' S., long. 109° E., bar. 29-1, ther. 36°, after some days wet and stormy weather. Soon after 8 P.M. the sky began to clear and the moon shone out. Noticing the light to the southward to be particularly bright I applied the spectroscope and found the distinguishing auroral line. About midnight I was called as there were very brilliant auroral clouds. The sky was almost clear, but so'.ith were two or three brilliant light clouds, colour very white yellow, shape cumulus stratus ; from about west to near south extended a long feathery light of the same colour, parallel with the horizon, and between south and west there appeared occasionally briUiant small clouds, the upper edges seemed hairy, and gave one the idea of a bright light behind a cloud. The forms changed, but I did not notice any particular order, perhaps because my attention was particularly directed to examining the light with the spectroscope, and the great cold, for my fingers seemed almost frozen, and the motion of the ship made my task rather difficult. I could trace four lines, three bright, and one rather faint, and by reference to the moon, which was shining brightly, roughly determined their places. They must have been exceedingly bright to show so plainly in full moon. The spectroscope used was one of Grubb's single prism with long collimator, A needle point in the eye-piece marked the position of the lines, and a conesponding needle point carried on a frame with the point in the eye-piece and moved by a coarse thread screw, scratched the lines on a plate of blackened glass. I took two plates ; — on the first I scratched the auroral lines and the telluric lines visible in the moonlight ; on the second I scratched the auroral lines, the telluric lines shown by the moon, and the lines given by carbon in the flame of a spirit lamp ; the next morning I verified the hnes in sunUght. The lines marked A are those shown A A A k \D ■Car. •:F ■G Car. Car. A<^ A by the aurora, those marked D, b, F, and G are the telluric lines, and those marked car. were given by the carbon in the spirit lamp. The spectrum has been magnified five times from the plates. I cannot account for the different position of the auroral lines in the two plates, as the prism was not moved during the observations that I am aware of. The fourth aurora was a slight one seen to the south- ward on March 6 at 8 P.M. It would be worth investi- gating whether the low barometer has anything to do with the absence of red in the spectrum, the normal state of the barometer is an inch lower in those regions than in more temperate latitudes. I may as well add that on February 9 the aurora was preceded by a watery sunset, and the day broke after- wards with high cirrus clouds and clear horizon. On February 21 the aurora preceded a fine morning, cumulus stratus clouds. On March 3 there was a brilliant sunset followed by a fine morning ; and on March 6, after the slight appearance of aurora, the clouds chansjed to high cirrus. J- P- Maclear ABSOLUTE PITCH AT the present time the question of absolute pitch is attracting attention in consequence of the discrepancy between Konig's scale and the numbers determined by Appunn's tonometer. This instrument is founded upon the same idea as Scheibler's fork tonometer, and consists of a s.ries of sixty-five harmonium reeds, bridging over an entire octave, and so tuned that each reed gives with its immediate neighbours four beats per second. The appli- cation to determine absolute pitch, however, does not require precision of tuning, all that is necessaiy being to count with sufficient accuracy the number of beats per second between each pair of consecutive reeds. The sum of all these numbers gives the difference of frequencies of vibration between the first reed and its octave, which is, of course, the same as the frequency of the first reed itself. The whole question of musical pitch has recently been discussed with great care by Mr. Ellis, in a paper read before the Society of Arts (May 23, 1877). He finds by original observation with Appunn's instrument 258*4 as the actual frequency of a Konig's 256 fork, and Prof. Preyer, of Jena, has arrived at a similar result (258 2). On the other hand. Prof. Mayer in America, and Prof. Macleod in this country, using other methods, have obtained numbers not differing materially from Konig's. The discrepancy is so considerable that it cannot well be attributed to casual errors of experiment ; it seems rather to point to some defect in principle in the method employed. Now it appears to me that there is such a theoretical defect in the reed tonometer, arising from a sensible mutual action of the reeds. The use of the instrument to determine absolute frequencies assumes that the pitch of each reed is the same, whether it be sounding with the reed above, or with the reed below ; and the results arrived at would oe vitiated by any mutual influence. In consequence of the ill- understood opera- tion of the wind, it is difficult to predict the character of the mutual influence with certainty ; but (" Theory of Sound," §§ 112-115) there is reason to think that the sounds would repel one another, so that the frequency of the beats heard when both reeds are sounding, exceeds the difference of the frequencies of the reeds when sounding singly. However this may be, in view of the proximity of consecutive reeds and of the near approach to unison,^ the assumption of complete independence could only be justified by actual observation, and this would be a matter of some delicacy. If the mutual influence be uniform over the octave it would require a difference of one beat per minute only to reconcile Konig's and Appunn's numbers. As to the amount of the influence I am not in a position to speak with confidence, but I may mention an obser- I It must not be forgotten that the vibration of the tongue involves a transference of the centre of inertia, so that there is a direct tendency to sst the sounding-board into motion. Nov. 1, 1877] NATURE 13 vation which seems to prove that it cannot be left out of account. If two sounds of nearly the same pitch are going on together, slow beats are heard as the result of the superposition of vibrations. Suppose now that a third sound supervenes whose pitch is such that it gives rapid beats with the other two. It is evident that these rapid beats will be subject to a cycle of changes whose fre- quency is the same as that of the slow beat of the first two sounds. For example, in the case of equal inten- sities of two sounds there is a moment of silence due to the superposition, of equal and opposite vibrations, and at this moment a third sound would be heard alone and could not give rise to beats. The experiment may be made with tuning-forks, and the period of the cycle will be found to be sensibly the same whether it be determined from the slow beat of the two forks nearly in uniFon or from the rattle caused by the simultaneous sounding of a third fork giving from four to ten beats per second with the other two. In the case of forks there is no fear of sensible mutual action, but if it were possible for the third sound to affect the pitch of one of the others the equality of the periods would be disturbed. The observation on Appunn's instrument was as follows : — The reeds numbered o and 64 being adjusted to an exact octave, it was found that the beats arising from the simul- taneous sounding of reeds o, 63, and 64 were by no means steady, but passed through a cycle of changes in a period no greater than about' five seconds. In order to work with greater certainty a resonator of pitch corresponding to reed 64 was connected with the ear by a flexible tube and adjusted to such a position that the beats between reeds o and 64 (when put slightly out of tune) were as distinct as possible, indicating that the gravest tone of reed 64 and the octave over-tone of reed o were of equal intensity. 'Qy flatteniiis: reed 64 (which can be done very readily by partially cutting ofT the wind) the beats of the three sounds could be made nearly steady, and then when reed 63 was put out of operation, beats having a 5 seconds' period were heard, indicating that reeds o and 64 were in tune no longer. It would appear, therefore, that when reed 63 sounds the pitch of reed 64 is raised, but in interpreting the experiment a difficulty arises from the amount of the disturbance being much in excess of what would be expected from the performance of the instrument when tested in other ways.' I come now to an independent determination of abso- lute pitch, which it is the principal object of the present communication to describe. The method employed may be regarded as new, and it appears to be capable of giving excellent results. The standard fork, whose frequency was to be measured, is one of Konig's, and is supposed to execute 128 com- plete vibrations in a second. When placed on its stand (which does not include a resonance box) and excited by a violin bow, it vibrates for a minute with intensity suffi- cient for the counting of beats. The problem is to compare the frequency of this fork with that of the pendulum of a clock keeping good time. In my experi- ments two clocks were employed, of which one had a pendulum making about li^ complete vibrations per second, and the other a so-called seconds' pendulum, making half a vibration per second. Contrary to expectation, the slower pendulum was found the more convenient in use, and the numerical results about to be given refer to it alone. The rate of the clock at the time of the experi- ments was determined by comparison with a watch that ' The value of my instrument has been greatly enhanced by the valuable assistance of Mr. Ellis, who was good enough to count the entire series of beats, and to compare the pitch with that of the tuning-forVs employed by him in previous investigations. Mr. EUis, however, is not responsible for the facts and opinions here expressed. It may be worth mentioning that the steadiness or unsteadiness of the beats heard when three consecutive reeds are sounding simultaneously is a convenient test of the equality of the consecutive intervals. The frequency of the cycle of the four a second beats is equal to the difference of the frequencies of either of the actual •extreme notes and that which, in conjunction with the other two, would 'make the intervals exactly equal. was keeping good time, but the difference was found to be too small to be worth considering. In what follows it will be supposed for the sake of simplicity of explanation that the vibrations of the pendulum really occupied two seconds of time exactly. The remainder of the apparatus consists of an elec- trically maintained fork interrupter, with adjustable weights, making about 12.V vibrations per second, and a dependent fork, whose frequency is about 125. The current from a Grove cell is rendered intermittent by the interrupter, and, as in Helmholtz's vowel experiments, excites the vibrations of the second fork, whose period is as nearly as possible an exact submultiple of its own. When the apparatus is in steady operation, the sound emitted from a resonator associated with the higher fork has a frequency which is determined by that of the interrupter, and not by that of the higher fork itself; nevertheless, an accurate tuning is necessary in order to obtain vibrations of sufficient intensity} By counting the beats during a minute of time it is easy to compare the higher fork and the standard with the necessary accuracy, and all that remains is to compare the frequencies of the interrupter and of the pendulum. For this purpose the prongs of the interrupter are provided with small plates of tin so arranged as to afford an intermittent view of a small silvered bead carried by the pendulum and suitably illuminated. Under the actual circumstances of the experiment the bright point of light is visible in general in twenty-five positions, which would remain fixed, if the frequency of the interrupter were exactly twenty-five times that of the pendulum. In accordance, however, with a well-known principle, these twenty-five positions are not easily observed when the pendulum is simply looked at ; for the motion then appears to be continuous. The difficulty thence arising is readily evaded by the interposition of a somewhat narrow vertical slit, through which only one of the twenty-five positions is visible. In practice it is not necessary to adjust the slit to any par- ticular position, since a slight departure from exactness in the ratio of frequencies brings all the visible positions into the field of view in turn. In making an experiment the interrupter is tuned, at first by sliding the weights and afterwards by soft wax, until the interval between successive appearances of the bright spot is sufficiently long to be conveniently ob- served. With a slow pendulum there is no difficulty in distinguishing in which direction the pendulum is vibrat- ing at the moment when the spot appears on the slit, and it is best to attend only to those appearances which correspond to one direction of the pendulum's motion. This will be best understood by considering the case of a conical pendulum whose rhotion, really circular, appears to be rectilinear to an eye situated in the plane of motion. The restriction just spoken of then amounts to supposing the hinder half of the circular path to be invisible. On this understanding the interval between successive ap- pearances is the time required by the fork to gain or lose one complete vibration as compared with the pendulum. Whether the difTerence is a loss or a gain is easily deter- mined in any particular case by observing whether the apparent motion of the spot across the slit (which should have a visible breadth) is in the same or in the opposite direction to that of the pendulum's motion. In my experiment the interrupter ^avos, eoi/ccos "ipiSt, t^v oktIvu Tjfxavpov. Prof. Grant considers that "the words here quoted refer beyond all doubt to a total eclipse of the sun, and that the phenomenon seen encompassing the sun's disc was really as well as verbally, ideiiticalwith the modem corona." He also points out that Plularch, i\W. I, 1877] NATURE Is who was contemporary with Apollonius, refers to a total eclipse of the sun which had recently occurred, and remarks of total solar eclipses in general that " a certain effulgence is seen round the circumference," so that although the sun may be wholly covered by the moon " still the eclipse is deficient in duration as well as in amplitude," this surrounding effulgence not allowing of a very intense shadow. These remarks of Philostratus and Plutarch Prof. Grant thinks may probably apply to the same eclipse, and afford "the earliest allusions to the corona recorded in history." Several attempts have been made to discover the date of the phenomenon, but so far as we know without success. The earliest distinct and more accurate account of the corona is that given by MM. Plantade and Capids, who observed at Montpellier on the occasion of the eclipse of May 12, 1706. The Outer Satellite of Mars. — Our ephemeris of the satellite of Mars is here continued ten days further from the elements employed last week, though much greater difficulty must now attend observations than when the discovery was first announced. In the middle of August the distance of the planet from the earth was less than o"4 ; on November 12 it will have increased to o'68. At the next opposition in 1879, the least distance of Mars will be o*482, at a north declination of upwards of 18°, so that observations may be made at many observatories in this hemisphere, probably without greater difficulty than about the late opposition ; at the following one in December, 1881, the planet will attain a declination of 27° N., but its distance from the earth will be at no time less than o'6o2. Prof. Asaph Hall's complete discussion of the observa- tions of the satellites of Mars, made in the present year, will be looked for with much interest ; it is only fitting that this investigation should be left in the hands of their discoverer, who has made the year 1877 a very notable epoch in the history of practical astronomy. The following positions of the outer satellite are for 8h. G.M.T. Nov. 3 ... Pes. 358 ... Dist. 21 ,, 4... ,, 69... „ 52 „ 5... „ 122... „ 25 „ 6... „ 236... „ 42 „ 7... „ 272... „ 37 De Vico's Comet of Short Period.— The year to which we drew attention some time since (i876"9-i877'9) as one which might possibly witness the re-discovery of De Vico's comet of 1844 is drawing to a close without its having been remarked, and the chance of detecting it at this season if the perihelion passage be not already passed, is small. We must therefore probably place the comet in the class which, though undoubtedly moving in elliptical orbits of small dimensions when under observa- tion, are now " lost." Whether in the case of De Vico's comet this arises from a larger error in the determination of the mean motion ini844than at present appears admissible, or whether the action of the planet Mars, to which allu- sion has been made in this column, may explain it, or again, whether the comet has encountered one of the minor planets, and thereby been deflected or disintegrated, cannot be at present ascertained. It was hardly to have been anticipated that the laborious investigations of Prof. Briinnow relating to the motion of this comet from 1844- 55 would not have resulted in its re-observation. METEOROLOGICAL NOTES Mean Atmospheric Pressure of Europe. — A great contribution to this very important subject has been made by Dr. Buys Ballot in the second volume of the " Nederlandsch Meteorologisch Jaarboek voor 1872," which has just been published. The first 130 pages of Nov. 8 . . Pos. 27 .. .Dist 2=; » 9" . » 75 • >> 48 „ 10.. • ,> ISO. »> 20 „ II ,. • „ 243. » 46 „ 12.. . „ 285. it 28 the volume are occupied with a very careful and in certain directions exhaustive discussion of the barometric obser- vations made at about no places situated in different parts of Europe from 1774 to 1874. The method of dis- cussion is identical with that adopted by Dr. Buys Ballot in his recently published paper on the Meteorology of Holland (Nature, vol. xvi. p. 89). This method consists in accepting as the normal mean atmospheric pressure at Greenwich, Vienna, and Palermo, the arithmetic means of the observations made at these places which embrace periods of 100, loi, and 84 years respectively. The normal values for the other stations have been determined by the process of differentiation, that is, by a comparison of the means of all the observations made at the place with the corresponding means of one or more places at the nearest available stations whose normals have been already determined, and thereafter applying the necessary correction. Thus the normals which have been arrived at in this very laborious manner are substantially the averages which would have been obtained if the obser- vations at each of the stations had been made during precisely the same terms of years. The thirty years' averages should probably have been accepted as the best normals for Stykkisholm in Iceland, instead of correcting these averages from the Greenwich and Christiania observations, seeing that a low average barometer at Stykkisholm is frequently coincident with a high baro- meter at either or both of these stations, and vice versd. The resulting differences, however, are but slight. This work of Dr. Buys Ballot, particularly when looked at with reference to future discussions, may be said to take a place at once as a classic of meteorology. The next step to be taken in this field of European meteorology is the discus- sion of all good barometric observations made in Europe during the meteorological lustrum ending with 1875. To the results of this discussion corrections could be applied from Du Buys Ballot's normals, which are sufficiently numerous for the purpose, and thus a graphic representa- tion could be made of the closest possible approximation to the true mean atmospheric pressure of Europe. In this way, by disclosing the striking, and in a large measure still unrecognised, influence of large masses of land and water on the barometric pressure, much light would be thrown on the origin and history of those great atmospheric currents which, flowing or sweeping over this continent, are mainly instrumental in determining the climates of its different regions. Meteorology of New York, U.S.— The "Annual Report of the New York Meteorological Observatory for 1876" gives, in addition to the individual observations made daily, and their monthly and annual averages, a more than usually full statement of rain and wind obser- vations. On pp. 39-88 are given the details of the amount of rain and snow-water which fell each hour from 1870 to 1876, together with the hourly averages of each month for these seven years. These hourly means show maximum amounts during winter, from 11 A.M. to 3 P.M. ; during spring, from 9 P.M. to i A.M. ; during summer, from 5 to 10 P.M. j and during autumn, from 3 to 8 A.M. The irregularity of these periods and the irregular occurrence of secondary maxima indicate that seven years is too short a time for the determination of the hourly curve of the rainfall at New York. There appears, however, a tendency to a double maximum varying considerably with season. Extended observation alone can give this curve. The influence of the daily fluctuation of temperature and of the sea breeze which sets in very decidedly from south-east during the hot months on the rain-curve, can then be studied. During the same seven years the duration of each shower has been noted in the number of minutes, the average result of which is that the minimum time of fall, a small fraction less than two days, cccurred in June ; from this time it slowly but steadily rose to 3 days i6 NATURE [Ni ov. I, 1877 17 hours in January, fell a little in February, and rose to 4^ days, the annual maximum in March, from which it rapidly declined to the minimum in June, On a mean of the past forty-one years the monthly averages are in excess from May to August inclusive, August and May being decidedly the months of maximum rainfall, whilst January and February are the months of least rainfall. From 1836 the annual amounts show with some interruptions a decided increase in the rainfall up to 1868, since which year there has been as decided a decrease. This result is generally corroborated by the rainfall at Washington, Philadelphia, and Providence, which Mr. Draper adds to his Report. A valuable table of the monthly amounts from 1836 to 1876 is printed at p. 6. In accordance with the suggestion thrown out by Mr. Hill (Nature, vol. xvi. p. 505) the amounts for the winter months have been picked out, averaged for the eleven-years sun-spot period, and bloxamed. The results, thus worked out, are in inches these, beginning with the first year of the cycle : — 22*57, 22'26, 22"92, 23"3i, 22*24, 2103, 21-98, 21*05, 21*14, 22*i8, and 23*56. Meteorology in Russia. — The St. Petersburg Agro- nomical Society has appointed a special committee for the purpose of elaboratmg, in accord with other Russian scientific bodies, a scheme for establishing throughout Russia an extensive net-vork of meteorological stations. Owing to the interest manifested in the subject by a great number of agriculturists, it is expected that the plan will soon be put into execution. NOTES We much regret to have to announce the death, on Sunday last, of Mr. Robert Swinhoe, F.R.S., a naturalist whose numerous contributions to our knowledge of the mammalia and birds of the Chinese Empire have proved invaluable to zoolo- gical science. We hope, next week, to give an account of Mr. Swinboe's woik. The International Committee for the erection of a monument to Liebig at Munich, having now at their disposal a sum of 120,000 marks, invite sculptors of all nations to send in models for their acceptance. A prize of 2,000 marks will b 2 given to the model which takes, the first place, and 1,500 to the second. The model of the statue should be forty centimetres, and of statue and pedertal about one metre in height. Models should be addressed to the "Castellan der koniglichen Akademie der Kiinste, 38, Unter den Linden, Eerlin," where they will be received from June 1 to 15, 1878, to be exhibited first at Berlin and then at Munich. The Committee bear all the expenses of transport. It has been noted in the French papers h propos of the recent colliery explosion, that M. Leverrier, when presiding at the meeting of the French learned societies at Easter, proposed to extend the telegraphic warnings of the International Meteo- rological System to the several French pits. The question of the illumination of mines by electricity has been revived by these ter- rible tragedies, and a number of interesting communications con- nected with that important topic will be presented and fully discussed at the next meeting of the French Academy of Sciences. It was stated by one of the speakers at the last quarterly meeting of the French Academies that M. Th ers had written a complete work on Spherical Trigonometry when quite a young man. We regret to record the death of M. Cazin, Professor of Physics at one of the Paris Lycees, and an active member of the Paris Ph>sical Society. M. Cazin was sent to the Island of St. Paul by the Academy of Sciences under the command of Capt. Mouchez to make physical observations during the last transit of Venus ; he there contracted the germ of the illness which has proved fatal at the early age of forty years. He had been admitted to the Observatory by M. Leverrier to execute a series ot delicate researches on magnetism, w^hich have been left unfinished. The Harveian Oration at the Royal College of Physicians ot London will be ^delivered in 1878 by Dr. J. Burdon Sanderson, F.R.S. An anthropological exhibition will be opened at Moscow in 1879, in connection with the society of Friends of Natural Science. Many objects of great scientific value, almost exclu- sively of Russian origin, are already in the hands of theorganising committee. Mr. Tuckwell, recently |,h6ad-master of Taunton College School, has issued a circular addressed to head-masters, giving an account of his connection with the school whose reputation he did so much to raise, and which has treated him so ungratefully. Our readers are already familiar with the details of this unhappy matter, and we are sure will all wish with us that Mr. Tuckwell may soon find a field for the exercise of his powers as a successful teacher unfettered by the narrowness of uneducated and narrow- minded directors. Mr. Tuckwell gave Taunton School a status and a name ; the Council of the school have undone all his work, and left the school nowhere. The winter session of the Chester Society of Natural Science opened on October 25 with a lecture on "The Arctic Regions," by Mr. de Ranee, of H.M. Geological Survey. The upper Silurian, lower carboniferous sandstones, mountain limestone, and lias of the Parry Archipelago, as well as the oolites, cretaceous and miocene rocks of Greenland and Grinnel Land, were de- scribed as occupying hollows in the old Laurentian Mountains, and the existing cold climate was stated to have probably only prevailed since the last glacial epoch. The range of the northern mammals, and the discovery of remains of the Eskimo by Capt. Feilden, R.N., naturalist of the Alert, near Cape Beechey, far north of the present limit of human habitation, and further north than any previous discovery of man or his works, were commented on j and a large collection of Arctic fossils were exhibited by Sir Phillip Egerton, collected in Grinnel Land by his nephew, Lieut. Egerton, R.N., of the late British Arctic Expedition. An unusually interesting scientific soiree was recently held at the Bristol Museum and Library, which has been characterised as "the headquarters of scientific research in the west of England." Many of the most recent scientific experiments were shown,fthe most attractive probably being Prof. Graham Bell's exhibition of the wonders of the telephone. During the winter a course of lectures has been arranged for at the museum, mostly scientific, as follows : — November 19— A. R. Wallace, F.R.G.S., F.L.S., the Distribution of Animals as indicating Geographical Changes; November 29 — Prof. Ball, F.R.S., a Night at Lord Rosse's Telescope, illustrated by the Oxy-hydrogen Lantern. December 10 — Frederick Wedmore, Rembrandt ; his Life and Work. January 14— Prof. Marshall, M.A., Principal of Uni- versity College, Bristol, The Economic Condition of America. January 28— Prof. W. C. Williamson, F.R.S., Coal and Coal Plants. February II— C. T. Hudson, M.A., LL.D., The Larger and Rarer Rotifers ; illustrated with Transparent Dia- grams. February 26— Prof. Rowley, M.A., of University Col- lege, Bristol, Francis Bacon : his Personal Character and Political Career. March 11— Dr. J. H. Gladstone, F.R.S., Fiery Meteors and Meteoric Stones. March 25— J. Norman Lockyer, F.R.S., Sun Spots in Relation to Indian Famines, with Spectroscopic Experiments and Oxy-hydrogen Lantern Illustrations. Nov. I, 1877] NATURE 17 The Royal Society of New South Wales, originated in 1821 as the Philosophical Society of Australia ; after an interval of repose it was revived in 1850 as the Australian Philosophical Society, by which designation it was known until 1856, when the name was again changed to that of the Philosophical Society of New South Wales, and finally, about ten years ago, by the sanction of her Majesty the Queen, it assumed its present title. Judging by its present list of members it would seem to be prospering, but judging from the volume of its Proceedings (vol. X. for 1876) its scientific life might be higher, and we would venture to express the hope that future volumes may give us a larger number of memoirs treating of that vast quadrilateral of which Sydney is the acknowledged cipital. Of the articles in this volume we would notice the following : On the Deep Oceanic Depression off Moreton Bay, by the Rev. W. B. Clarke, F.R.S. ; On some Tertiary Australian Polyzoa, by the Rev. J. E. T. Woods. The species were with one exception derived from the Mount Gambier polyzoan limestone, South Australia, and are all described as new ; ten are described and figured as belonging to the genus Eschara, two species of the genus Pustulipora are described, and one Tubulipora. On the forma- tion of Moss Gold and Silver, and on a Fossiliferous Siliceous Deposit from Richmond River, is the title of a paper by Prof. Liversidge. The composition of this deposit shows that it answers to the common siliceous sinters or geyser deposits. The weathered surfaces are usually marked with the remains of ferns which stand out in relief, and more rarely through the mass ' are to be found the remains of certain fruits and seeds. These latter have been described by Baron Mli ler as belonging to a plant (Liversidgea oxyspora) allied to Capparidete and Bixacese, the fruits are from two-thirds to nearly an inch in diameter, divided info four turgid lobes, placentas parietal ; seeds turgid ; oval towards one extremity and attenuated at the other ; both fern and fruits are figured. In the discussion following the reading of a paper by the Rev. W. B. Clarke, F.R.S., On the Effects of Forest Vegetationjon Climate, many interesting statements were made as to the condition of the forests in the neighbourhood of Sydney at the present tinie, and so long back as forty years ago. Petermann's Mittheilungtn for November contains a paper by Dr. G. Radde describing the journey of himself and Dr. Sievers from Erzeroum to the Bin-Gol-Dagh ; the paper is full of details concerning the botany of the region traversed. Under the title of •* Tekna and Nun," Dr. Rohlfs gives some valuable information on the part of the Sahara about the south-west of Morocco, showing that it is by no means so barren as is gene- rally thought, and that even the most recent maps of the region are unsatisfactory. One of the most interesting papers in the September number of the Buhetin of the French Geographical Society is an account by M. Brau de St.-Pol-L'ais of his visit to the French Colonial stations recently established on the coast of Sumatra, in the province of Deli. The author gives many interesting observa- tions on the people and the products of the part of the island which he visited, and speaks hopefully of the colony, which he considers an excellent basis for the exploration of the island. In the same number Dr. Harmand gives some account of recent journeys he made in Cambodia. The first map showing the whole of Stanley's" route from Bogomayo to the mouth of the Congo has been published by L Exploration (October 21). In this map the course of the Congo is roughly shown as indicated in Stanley's letter, and that also of the Ogove according to the explorations of de Brazza, Lenz, and Marche. The trend of the Ogove to the south-east is shown, and its probable junction with the Congo by two arms indicated. The Geographical Society of Paris has received letters from the French Consul at Zanzibar informing them that a road is being opened from Zanzibar to Tanganyika, for carting by oxen. It is expected that ere long explorers will be able to dispense with native porters. A Geographical paper has been started at Lyons by M. du Mazet, one of the staff of the Courrier de Lyon. It will record the transactions of all the provincial geographical societies of France. The Lyons Geographical Society will have the advantage of a number of communications from the Roman Catholic mission- aries who have an old-established special seminary and college in that city. In the Times of Wednesday last week appeared a long story about ♦he discovery of the remains of Columbus in St. Domingo. At Madrid, the Times Paris correspondent now states, the story is declared to be a hoax, inasmuch as "a Spanish squadron years ago escorted the remains to Havannab, where they lie in the Cathedral." Under the title of " Pictorial Geography for Young People," Messrs Griffith and Farran have published a neat little map intended to exhibit giaphicilly the significance of the various terms used in geography — continent, island, river, lake, mountain, volcano, city, &c. It is necessarily exaj.;gerated, but in the hands of a judicious teacher might be a valuable and attractive help to the teaching of the elements of geography. Two severe shocks of earthquake were experienced at Lisbon at 6.45 A. M. of October 25. No damage was reported. Under date October 17, it is reported from Smyrna, in Asia Minor, that there had been, during a few days, several eaith- quake shocks doing'no further harm but cracking some walls. It has been affirmed by P. Secchi of Rome, that iron heated red is transparent to light. This is denied by M. Govi of Turin, who, in a paper to the French Academy, describes some experi- ments on the subject, and shows how one may be deceived in study- ing the phenomena. If a mixture of borax and carbonate of soda be fused in a thin platinum crucible raised to a red heat, there will be seen on the exterior of the vessel the form of the liquid mass with all its accidents of rapidly varying form, indicated by a zone of less brightness than the upper portion of the metallic surface. At first sight it is natural to infer a transparence for light of the heated platinum, but (M, Govi points out) the case is really one of transparence for radiant heat ; that is to say, a phenomenon connected with the good conductivity of platinum. The liquid, liberating carbonic acid, is less hot than the crucible, and is constantly borrowing heat from it. It is inevitable, then, that at every point where the liquid touches the metal, the latter relatively cooled, should appear less luminous than in the neigh- bouring region. M. Govi gives some other examples of the phenomenon. " Shorthand for General Use " is the title of a little volume by Prof. Everett, of Belfast, published by Marcus Ward and Co. Prof. Everett's system claims several advantages over Pitman's, one being that the vowels can be written continuously with the consonants, and thus the word has not to be gone over a second time to insert the vowels. The system appears to us decidedly worth the attention of anyone wishing to learn short- hand. We have received the eighth edition of Prof. Atkinson's translation of Ganot's " Physics." About sixty pages of addi- tional matter, with an equal number of illus rations, have been added to this edition. Messrs. Longmans and Co. are the publishers. Another scientific play is now being performed at the Cluny Theatre, Paris, under the title of the " Les 6 Parties du Monde.'* It is written by M. Figuier, the well-known scientific story-teller. The sixth part of the world is supposed to be the Antarctic NATURE \l^ov. 1, 1877 continent, where Dumont Durville is made to land. It is a masterly panorama of a number of climes and countries, enlivened by a well-constructed plot. Dr. Hoek, of Leyden, sends us the following additions to the list of dealers in zoological specimens given by Prof. Ray Lankester in a recent number of Nature :— i. Hilmar Liihrs, Fischer f. Zoologen und Aquarien, Helgoland (Unterland), for fish and invertebrates (alive and in spirits, specimens of all classes). 2. The Zoological Station of Dr. Anton Dohrn, Naples, for fash and invertebrates (spirit specimens). The additions to the Zoological Society's Gardens during the past week include three Tigers {Felis iigris), born in the Gardens, but did not survive; a Common Genet {Genetta vul- garis) from North Africa, presented by Mr. P. V. Carletti ; two Hyacinthine Porphyrios [Porphyria hyacinthinus) from West Asia, presented by Mrs. Henry Cobb ; two All-Green Parakeets (Brotogerys tiriacula) from South America, presented by Miss Rowe ; two Yellow-bellied Liothrix {Liothrix licteus) from India, presented by Gen. Breton ; two common Marmosets {Bapale jacchus) from South-east Brazil, presented by Mrs. Clayton ; three Darwin's Pucras {Pticrasia darwini), a Chinese Blue Magpie {Urocissa sinensis) from China, a Sun Bittern (Eurypyga Julias) from South America, deposited ; a Moose [Akes machlis) from North America, purchased. AMERICAN SCIENCE pROF. HENRY'S portion of the report of the Smithsonian *■ Institution for the year 1876 has been printed in separate pamphlet form, in advance of the entire volume, and gives the usual record of operations for the period. It draws attention to the fact that it is the thirtieth of the annual series made by him, and that the policy advised at the first meeting of the board has been carried out with scarcely any modification. The original fund of 541,379 dols. has been increased to 714,000 dols., although a building costing nearly 500,000 dols. has been erected. There is a library of 70,000 volumes of the most valuable class of books, namely, the serial scientific publications of learned societies. The museum has grown until it now ranks among the best in existence. This embraces copious collections illustrating the ethnology and natural history of the world. The institution has published twenty-one quarto and forty -two octavo volumes of transactions and reports. It has carried on successfully a great system of meteorological observations (only intermitted on the successful operations of the Signal Service), the results of which have been issued by a number of stately volumes. It is now prosecuting a great system of international exchanges, for the benefit of the whole world. Its correspon- dence, both at home and abroad, requires a large number of clerks and specialists ; and the name of Smithson is universally known in consequence. Details have been recently published {Proc. Acad. Nat. Sci. Philadelphia, 1877, p. 255) of the exploration of a specially interesting mound at Coup's Creek, Macoupin County, Illinois. Four skeletons sat within it, considerably enveloped in a peculiar granulated but exceedingly tenacious earth. They were placed two and two, their arms crossed, the knees of one pair pressing sharply against the backs of the other, and the faces of all turned directly toward the east. Though the greatest care was taken, only one skull was removed comparatively perfect. The whole grave measured but six feet in length by three in width, and it contained in addition to the skeletons four large marine shells of Pyrula {Busycon) perversa (Luin.), each similarly placed in rela- tion to the bodies. The smaller end of one shell was placed in the right hand of each individual, while the larger portion rested in the hollow above the left hip. But, still more remarkable, within each shell had been packed what appeared to be the bones of a child ; the skull, crushed before burial, protruded beyond the aperture. The suggestion is made that these infants were sacrificial offerings in honour of the dead. The graves in these mounds are constructed of stone slabs from the locality, and hence they are known as stone graves. The builders give evidence of decided constructive ability, and of having been careful culti- vators of the soil. The grave-mounds are found upon ridges, while others on which dwellings were supported are near streams. A systematic series of mounds of similar origin extends from the foot of Lake Michigan to the mouth of the Illinois river, a distance of two hundred and fifty miles. Unfortunately the remains are scarcely ever capable of being preserved, or even of being examined satisfactorily on exhumation. The following are notes of papers in the October num- ber of the American Journal of Science and Arts : — The nickel plates now largely used as anodes for nickel plating are prepared by fusing commercial nickel, generally with addition of charcoal, and casting in suitable form. From an analysis of several specimens of cast nickel by Mr. Gard, it appears that silica may be reduced and retained as silicon, and that a considerable amount of caibon may be present {e.g., I '9 and I "8 per cent.). One experiment made with a view to asceriain how much carbon nickel may take up under conditions to which it is more or less exposed in the processes of manu- facture and casting, was to pack half-a-pound of granular com- mercial nickel in layers with charcoal in a Hessian crucible, in which it was exposed to a full red-heat twelve hours. No fusion took place. The temperature was then raised till there was com- plete fusion. The resulting metal was strongly magnetic, quite soft, and to a considerable extent malleable. Its specific gravity was 8 04, and it had a fracture like that of fine-grained pig-iron, scales of graphite being plainly visible. It was found to contain of total carbon 2-105, 2-130; graphitic carbon, 2,030, 1-990; silicon, -360. Mr. Gard also made some experiments on the deportment of nickel and cobalt towards hydrocarbon at a high temperature, the substances being placed in a platinum trough within a porcelain tube and treated with a slow current of pure dry marsh-gas at a full red heat. In one case thin plates of pure electroplate nickel ('8597 gr.) were found at the close to have gained 10-649 per cent. ; in another 1-2697 gr. of cobalt gained 12-758 per cent. Among other chemical contributions we note one on the iodates of cobalt and nickel, by Mr. Fallarton, who finds that the true normal iodates contain really six molecules of water of crystallisation, and that they are essentially different from the salts obtained by Rammelsberg. Several specific-gravity deter- minations follow (by students of Cincinnati University), including those of a series of chromates, by Miss Abbot. Pettersson has lately shown that selenates have molecular volumes exceeding those of the corresponding sulphates by six for each molecule of the acid radicle. On comparing the chromates with Pettersson's selenates, it is found that the two series of salts have approximately equal molecular volumes ; the difference, if any exists, being very slightly plus for the selenates. If regularities of this kind can be thoroughly established, it will be easy (Prof. Clark suggests), having the density of a chromate, to calculate that of the corre- sponding sulphate or selenate, or vice versa. A preliminary catalogue of the reptiles, fishes, and Lepto- cardians of the Bermudas is furnished by Mr. Brown Goode, comprising 148 out of 163 known specie?. The Bermudan fauna shares with the West Indies 116 species (or 79 per cent.), of which 58 (or 40 per cent.) are peculiar to the West Indies, while many others have their centres of distribution in that region. With the Eastern United States Bermuda shares 47 species, and with the waters of the Pacific and Indian Ocean 32 species. Mr. Goode also gives a description of four species of fishes believed to be new. Prof. Dana draws some lithological and orographic conclu- sions in his (continued) paper on the relations of the geology of Vermont to that of Berkshire, and the /ournal . sX%o contains some information on the Archaean of Canada and the geology of New Hampshire, &c. THE EARTHWORM IN RELATION TO THE FERTILITY OF THE GROUND FROM observations extending over a number of years, M. Hensen is led to the conclusion that infertile undersoil is rendered valuable by the action of worms in two ways, viz., by the opening of passages for the roots into the deeper parts, and by the lining of these passages with humus. This will be more fully under- stood from the following facts regarding the life-habits of the worm {Lumbricus terresiris) given in M. Hensen's paper in the Zeitschrift fiir zvissenschaftliche Zoologie. It is known that the adult animals in wet weather come up to the surface by night, and, with their hinder end in their tube, Nov. I, 1877] NATURE 19 search the ground round about. They then draw whatever vegetable material they can find into their tubes — fallen stems and leaves and small branches. In the morning one then finds little heaps of plant-fragments projecting at various parts of the surface, and each of them penetrating the tube of a worm. On closer examination it is found that the leaves have each been rolled together by the worm, and then drawn into the tube in such a way that the leaf-stalk projects. The portion of the leaf in the tube is moist and softened, and only in this state are plants consumed by the worm. There are distinct indications that the worm gnaws them, and after some days the meal is ended. The food is never drawn deeper down into the ground. In digging tlie ground at various seasons it was only very rarely that plant remains were found in the subsoil, and probably they got there by accident. With reference to the structure of the worm-tubes, some in- teresting facts were established in these researches. In humus their character is difficult to make out, owing to the looseness of the mass. In sand they proceed almost vertically downwards three, four, or even six feet, whereupon they often extend some distance horizontally ; more frequently, however, they terminate without bending. At the end of the tube the worm is found with his head upwards, while round about him the tube is lined with small stones. On the sandy wall of the tube one observes more or less numerous black protuberances which make the sand fertile. These are the secretions of the worm, which, after being removed out of a tenanted tube, are found next morning replaced by fresh matter. They are observed after a few days, when a worm is put in a vessel with clean sand, and allowed to make a tube for itself. Older abandoned tubes are pretty regularly lined with the earth formed by the worm, and some passages are densely filled with black earth. This black substance appears to diffuse somewhat into the sand. In about half of the tubes, not quite newly made, M. Hensen found roots of the plants growing at the surface, in the most vigorous development, running to the end of the tube and giving off fine root-hairs to the walls, especially beautiful in the case of leafy vegetables and com. Indeed such tubes must be very favourable to the growth of the roots. Once a root-fibre has reached such a tube it can, following the direction of gravity, grow on in the moist air of the passage, without meeting with the least resistance, and it finds moist, loose, fertile earth in abundance. The question whether all roots found in the under-soil have originally grown in the tubes of worms, cannot be answered with certainty. It is certain that the roots of some plants penetrate themselves in the sand, but not to great depths. M. Hensen is of opinion that the tap-roots, and in general such root-forms as grow with a thick point, can force a path for themselves, while the fine and flexible suction-roots have difficulty in obtaining a path into the depths other than what has been previously made for them. Roote of one year's growth especially can penetrate deep into the sub-soil, only where there are earth-worms. A microscopical comparison of the earth deposited by the worm shows that it is like the two-year leaf-mould prepared by gardeners for the filling of flower-pots. Most of the plant-cells are destroyed ; still there are present some cells and shreds of tissue, browned and friable, mixed with many sand grains and brown organic fragments. The chemical composition of the worm-earth shows much similarity to that of fertile humus ground. Its fertility, therefore, cannot be doubted, though direct experiments with it are wanting. With regard to the numerical value of this action of the earthworm, the following observations by M. Hensen afford some information. Two worms were put into a glass pot 1 4 foot in diameter, which was filled with sand to the height of i^ foot, and the surface covered with a layer of fallen leaves. The worms were quickly at work, and afier 14 month many leaves were down 3 inches deep into the tubes ; the surface was completely covered with humus i cm. in height, and in the sand were numerous worm-tubes partly fresh, partly with a humus wall 3 mm. thick, partly quite filled with humus. Counting, when an opportunity offered, the open worm-tubes in his garden, M. Hensen found at least nine in the square foot. Ino 15 square metres two or three worms were found in the deeper parts each weighing three grammes : thus in the hectare there would be 133,000 worms with 400 kilos, weight. The weight of the secretions of a worm in twenty-four hours was 05 grammes. While these numbers are valid only for the locality referred to, they yet give an idea of the action of this worm in all places where it occurs. The assertion that the earthworms gnaw roots is not proved by any fact ; roots gnawed by worms were never met with, and the contents of the intestine of the worms never included fresh pieces of plants. The experience of gardeners that the earth- worm injures pot plants may be based on the uncovering or mechanical tearing of the roots. " Let us take a retrospective glance," concludes the author, "over the action of ths worm in relation to the fertility of the ground. It is clear that no new manure material can be pro- duced by it, but it utilises that which is present in various ways. I. It tends to effect a regular distribution of the natural manure material of fields, inasmuch as it removes leaves and loose plants from the force of the wind and fixes them. 2. It accelerates the transformation of this material. 3. It distributes it through the ground. 4. It opens up the undersoil for the plant roots, 5. It makes this fertile. UNIVERSITY AND EDUCATIONAL INTELLIGENCE Oxford. — The University Commissioners are at present occu- pied in taking evidence on the subject of University requirements. The Dean of Christ Church, the Master of Balliol, the Master of University, the Librarian of the Bodleian, Profs. Clifton, Bonamy Price, Bartholomew Price, Stubbs, and others have appeared, or are to appear during the present week, before the Commissioners. Mr, Lazarus Fletcher, B.A., of Balliol, has been elected to the vacant Fellowship at University College. Mr. Fletcher obtained a first class in the School of Mathematics in 1875, a first class in that of Natural Science in 1876, and the senior mathematical scholarship in 1876. It is proposed to found a high school for the City of Oxford, the mayor, aldermen, and citizens having long felt it a re- proach that, being the site of one of the most ancient and famous of the Universities of Europe, it has been absolutely without any recognised grammar school available for the sons of the citizens. London. — Prof. W. K. Clifford, F.R.S., is at present delivering at University College a very interesting course of Lectures on Quaternions. The main object of the course is to bring the physical applications of quaternions as much as possible within the reach of mathematicians of moderate attainments. A requisition is in course of signature to the chairman of Convocation of London University, Dr. Storrar, asking that an extraordinary meeting of that body may be convened for the purpose of considering and discussing the following resolution?, and for deciding with reference thereto in such manner as to Convocation may seem fit: — "That it being manifestly inex- pedient that frequent application should be made to the Crown for new and additional charters, it is desirable that provision should be made in any such charter for all changes in the con- stitution of the University, either at the time urgent or likely to be soon required ; and that it being probable that initiative measures will be shortly taken towards procuring such a new or additional charter, the following proposals require the serious consideration of Convocation and the Senate : — ' (l) An enlarge- ment of the powers directly exercised by Convocation ; (2) An increase in the proportion of senators to be nominated or elected by Convocation, and the limitation of the tenure of office in the case of all senators to a term of years ; (3) The encouragement of mature study and original research among the members of the University, by the establishment of University lectureships, of limited tenure, in different departments of learning and science ; (4) The introduction into the constitution of the University of such modifications as may remove all reasonable ground of com- plaint, on the part of any of the affiliated colleges, with respect to the absence of means for expressing opinion and giving advice to the Senate on the examination regulations, and on the changes proposed to be made therein from time to time. And that a Special Committee of ten members of Convocation be appointed to consider the above-mentioned proposals, and to report thereon to Convocation as speedily as possible.' " The Entrance Science Scholarships in St Thomas's Hospital have been awarded this year as follows : — The Scholarship of 60/. to Mr. Wansborough Jones, B.A. Oxon., and B.Sc, London ; and that of 40/. to Mr. A. E. Wells. 20 NATURE \Nov. I, 1877 Bristol. — A well-printed and well- arranged Calendar of University College has been published. It extends to upwards of sixty pages, and contains all the information usually found in such publications, including full details as to the Medical School. Dean Stanley's address on Education, at University College, on Saturday, attracted an audience of about 1,700 people, who listened with the closest attention. SCIENTIFIC SERIALS Kosmos, Part 2 (May) opens with an article by L. Overzier, on " Heredity" (Part i), aiming at the discovery of the real cause of inheritance. — Prof. Jiiger, commencing a series of articles on " The Origin of Organs," deals with the development of the eye, showing bow the laws of optics and the properties of living substance mutually influence one another. — Hermann Miiller, treating on " The Origin of Flowers," considers the first metasperm (or angiosperm) to have been diclinous and fertilised by the vi^ind, that is, supposing the meta-.perms to have origi- nated from a single stock. — W. O. P'ocke deals with "The Conception of Species in the Vegetable Kingdom," especially in relation to the genus Rubus. He shows how far the different species are from being of equivalent value and that the term variety has no definite significance. He exposes the futility of much botanical "research," owing to imperfection of methods and lack of comparative study ; Darwin has few imitators. Such work requires an entire devotion of time and complete botanical gardens, for the multiplication of which the author calls. — A.. Lang, on Lamarck and Darwin (I.), expoimds Lamarck's con- ceptions of natural history. Kosmos, Part 3 (June). — L. Overzier continues his discussion of heredity, reviewing Darwin's theory of pangmesis, Haeckel's perigenesis, and Jager's chemical theory ; he considers the latter to be of great value. — Carl du Prel, on the needed remodelling of the nebula hypothesis. — Prof. Jiiger treats of the origin of the organ of hearing, tracing it from the simplest condition where spicules diffused through the entire protoplasmic body of an animal serve to gather up and conduct vibrations of sound. He brings forward the remarkable theory that in animals possessing nerve fibres, the organs of hearing is but a specialisation from the general tactile sense. — W. von Reichenau, on the colours of bird's eggs, makes tbe generalisation that birds having open nests have coloured eggs, while those with covered or concealed nests have white ones ; further, that in open and ground nests the colour of the eggs has a protective object. — A. Dodel-Port, on the lower limit of sexuality in plants, gives an account of the sexual processes in Ulothrix zonata, but appears not to have heard ot the researches of Dallinger and Drysdale on the monads. — A. Lang, on Lamarck and Darwin, expounds Lamarck's "hydro-geology." SOCIETIES AND ACADEMIES Paris Academy of Sciences, October 22. — M. Peligotin the chair. — The following papers were read : — M. Leverrier's tables of Uranus and Neptune, by M. Tresca. — On some applications of elliptic functions (continued), by M. Hermite. — Resume of a history of matter (first article), by M. Chevreul. This is an extract from a work commenced about the end of last year, and occupying 418 pages of the Memoires de I' Acadimie, t. xxxix. A sketch ot the principles of alchemy is given. — On one of the causes of red coloration of the leaves of Cis^us quinquefolia, by M. Chevreul. This cause is sunlight. The green colour is retained in the leaves that are shaded by others. — On the order of appearance of the first vessels in the shoots of some Legumi- nosae, by M. Trecul. — Modifications in the conditions of maxima of electro-magnets by the state of mo'e or less complete satura- tion of their magnetic core, by M. Du Moncel. The law of proportionality of the attractive forces to the squares of the intensities of the current is true only within certain limits, and under certain conditions ; and electro-magnets through which the current is interrupted at very short intervals, are (more or less) not subject to it. When the forces are proportional to (say) the cubes of the electric intensities, the helices must always be less resistant than the exterior circuit. In the case of multiplied interruptions, the resistance of electro-magnets must always be less the shorter the duration of closures of the current ; and for this reason (also because of defective insulation and extra currents; telegraph electricians reduce considerably the resistance of electro-magnets applied to Jong circuits. Reverting to the question in the title, the thickness of the magnetising spiral may be increased in case of defective saturation of the magnetic core ; becoming double the diameter of this if the force increises as the cube of the intensities. — Preparations of sulp'iide of carbon brought to the silid state by m-ans of gelatine, by M. Cassius. 100 grammes of gelatine are dissolved in i,ooo grammes of water, and sulphide of carbon (25,50, or 75 per cent.) is mixed at a tem- perature of 15° to 20°, and the'mixture let coal. M. Cassius thinks the preparation might be useful in viticulture. The sulphide is liberated slowly, the time varying according to the proportion of sulphide absorbed. — Experiments on the formation ot artificial ultramarine, by M. Piicque. He finds (in opposition to soma German authors) that ultramarine does not contain nitrogen. Blue ultramarine, properly so called, is formed by an oxy- genated conpound of sulphur, an! it is probable that this compound is fixed both by sodium and by aluminium. — On the catechines and their constitution, by M. Gautier. — On acid acetates, by M. Villiers. The increase of weight of some neutral acetates, dried and placed, in a summer month, under a bell jar with crystallisable acetic acid, was, in the case of acetate of soda, 404 per cent. , or nearly six equivalents of acetic acid ; acetate of potash, 264 p;r cent ; of baryta, 179 per cent. ; of lead, 134 per cent, &o. The solutions of neutral acetates in crystallisable acetic acid have much less tension of vapour than that of acetic acid. — Researches on butylene and its derivative?, by M. Puchot. — Note 01 the cxuse of anthrax, by M. Klebs. — On the structure of the blood corpuscle, and the resistance of its envelope to the action of water, by MM. J. Bechamp and Biltus. The demonstration of the membrane (by action of soluble fecula) is here given in the cases of the frog, the ox, the pig, and the sheep. Water does not destroy the globules ; it merely renders them invisible, and they may always be discovered with the aid of picrocarmin ite, even in extremely dilute media, and after several weeks of contact. The blood of sheep (like that of the hen in M, A. Bechamp's experi- ments) contains globules of more delicate structure than those of the other bloods examined. — Researches on the functions of leaves of the vine, by M. Macagno. Glucose and tartaric acid are formed preferably in the upper leaves of the fruit-bearing vine- branch ; this production of sugar progresses with that of the grape, and is much reduced (even to disappearance) after the vintage. The green branches are conductors of glucose. These facts explain the evil of "pinching" or remjving the tops of the grape-bearing branches, with too great zeal. Where there is an abundant product! m of grapes, a sufficient quantity of leaves should be left for prep tration of the necessar/ glucose. — Reply to a recent note of M. Bays Ballot, on the division into time and into squares of maps of nautical meteorology, by M. Brault. CONTENTS Pack The Sun's Distance i Parker AND Bbttanv's "Morphology OF THE Skull" 3 Thomson's " Sizing of Cotton Goods " 4 Our booK Shblf : — Aveling's "Physiological Tables for the Use of StUQents."^A. G. 5 Letters to the Editor : — Indium in British Blendes.— Prof. Nevil Story Maskklvne, F.R.S 5 The Radiometer and its Lessons. — Prof. G. Carey Foster, F.R.S. ; William Crookbs (The Ortho-Crookes?), F.R S 5 Mr. Wallace and Reichenbach's Odyle.— Alfred R. Wallace ; Dr. William B. Carpenter, F.R.S 8 Potential Energy. — E. G 9 Hartlaubs "Birds of Madagasjar."— Prof. Alfred Newton, F.R.S 9 Eucalyptus. — Prince Pierre Troubitzkoy ; Arthur Nicols . . lo Meteor of October 19, 6.15 p.m.— W. F. Denning (With Illustra- tions) 10 Curious Phenomenon during the Late Gale. — A. W. B. J. . . . 10 Singing Mice — Henry H Slater 11 Sound-Producing Arthropods. —W. Savillk Kent 11 Insects and Flowers. —A. J. H 11 Francis VON Rosthorn. By Prof. E. Suess 11 Spectrum of Aurora Australis. By Commander J. P. Maclear {With Illustration) " Absolute Pitch. By Lord Rayleigh, F.R.S 12 A New Condensing Hygrometer. By M. Alluard {With Illtis- tration) ^4 Our Astronomical Column :— Early Observations of the Solar Corona 14 The Outer Satellite of Mars 15 DeVico's Comet of Short Period iS Meteorological Notes 15 Notes 10 American Science ^ /-,•••'„ The Earthworm in Relation to the Fertility of the Ground t8 University and Educational Intelligence 19 Scientific Serials ^° SociBTiBS AND Academies "o NA TURE 21 THURSDAY, NOVEMBER 8, 1877 EXPLOSIONS IN MINES AFTER the occurrence of great colliery explosions such as those which took place recently in Pem- berton and Blantyre collieries, one very general and pertinent question presents itself to most minds, namely, What has been done or attempted with the view of preventing these disasters? It would be impossible to condense into an article hke the present all that could be said in reply to this question, but I shall endeavour to give a brief outline of the subject, and point out, as well as I can, what appear to be its most prominent features. Before the invention of the safety-lamp, the only means of guarding against the ignition of firedamp consisted in the employment of an apparatus called the " st^el mill." The light obtained by its aid was feeble and uncertain, and Mr. Buddie informs us that explosions were known to have been caused by the sparks emitted by it. When Davy made his brilliant invention in 1 815-16, the steel mill was laid aside for ever, and it was then imagined that colliery explosions had also become phe- nomena belonging to a past order of things. So con- fident, indeed, was Davy in the efficacy of his lamp, that he believed it could be safely employed for carrying on work in an explosive atmosphere ; and he even went so far as to propose to make use of the firedamp itself as the light-giving combustible. These fond expectations were soon roughly dispelled, as one explosion followed another in an apparently unaccountable manner ; and at length they were succeeded by a feeling of positive dis- trust, which found expression in the report of a select committee appointed, in 1835, to inquire into the nature of accidents in mines. In 1850 Mr. Nicholas Wood made a series of experi- ments, which proved that when a Davy lamp is subjected to an explosive current travelling at the rate of eight or nine feet per second, the flame soon passes through the wire gauze. This was corroborated about 1867 by experi. ments conducted by a committee of the North of England Institute of Mining Engineers. Lastly, in 1872-73, the writer demonstrated, also by experiment, that when a lamp burning in explosive gas is traversed by a violent sound- wave, such as that produced by a blasting shot, the same result follows, that is, ignition is communicated to the outside atmosphere. These are weak points inseparable from the construction of the ordinary Davy and Clanny lamps ; but as it is now a thoroughly-recognised maxim that work must never, under any circumstances, be continued in an explosive atmosphere, they are seldom put to the test. The atmosphere of part of a mine may, however, become explosive before the men can escape, either by the sudden influx of a quantity of firedamp from some natural cavity in which it had existed in a state of tension, or by a partial or total cessation of the ventilating current ; and I propose in the next place to consider how such an event could produce an explosion supposing all the men to be pro- vided with safety lamps. This will happen, firstly, if the inflammable gas passes over a furnace at the bottom of the upcast j Vol. xvii, — No. 419 secondly, if it is carried against a Davy or Clanny lamp at a greater velocity than seven feet per second, or if the lamp is traversed by a sound-wave ; thirdly, if a blasting shot is fired directly into it ; and lastly, if it reaches a safety lamp that has been opened by one of the men. The means that have been provided for guarding against these contingencies are as follow : — i. Furnaces have to a large extent been replaced by ventilating fans in fiery collieries. 2. Davy and Clanny lamps are still almost universally employed, and little importance seems to be attached to their known imperfections by those who are supposed to be capable of deciding the question. 3. Shot-firing having been found to originate many explo- sions, although probably in a manner not yet understood by most people, is now carried on under certain re- strictions which it could easily be shown are still insufficient. 4. Much nonsense has been talked and written about miners opening their lamps. That they sometimes do so is beyond a doubt ; but why should this state of matters be allowed to continue when it can be easily put an end to ? The present flimsy pretence for a lock is not a necessity but a cheap convenience ; and who is responsible if say a hundred men are killed through its being opened by one ? Is there no responsibility attach- ing to the owners or the legislature for placing the lives of ninety-nine innocent men in danger ? I think surely there is. The influence of changes of weather on the internal condition of mines has been remarked since the remotest times, and for the last fifty or sixty years at least many have asserted that firedamp is more prevalent when the barometer is low than in the opposite case. The explanation of the?e phenomena is easily found by any- one who has an elementary knowledge of the physical properties of gases. On the other hand, when vigorous artificial means of ventilation are employed, and ordinary skill practised in distributing the air, the effects of changes of weather become much less perceptible. Hence if a large proportion of explosions can be shown to occur simultaneously with, and therefore, presumably, in consequence of, those atmospheric changes that would tend to augment the amount of firedamp in the workings, there is a strong argument in favour of the supposition that they are preventible, and cannot therefore be consi- dered as accidents in the true sense of the term. With this object in view diagrams have been made from time to time by Mr. R. H. Scott and myself, and also by one or two others, showing the connection that exists between the two classes of phenomena, and an examina- tion of these is sufficient to convince unbiased persons that there is a striking coincidence between the explo- sions and the favourable atmospherical conditions. As might, perhaps, be expected, some persons engaged in mining either fail to see the connection, or possibly they do not understand it. Nevertheless a general rule was inserted in the Coal Mines' Regulation Act (1872) making it compulsory for mine-owners to place a baro- meter and thermometer at the entrance to every mine in the coal-measures. It has always been difficult, and sometimes impossible, for mining men to give an adequate reason for the extent of great explosions, and more especially when it is known thatj immediately beforehand, little or no inflam- c 22 NATURE \Nov. 8, 1877 mable gas has been present in the workings. The reports of the Inspectors of Mines bear ample testimony to the correctness of this statement. It has therefore been cus- tomary in the absence of any other tenable hypothesis to assume that a large volume of firedamp had been suddenly poured into the workings. But these so-called "out- bursts of gas " are entirely unknown in some localities in which great explosions have occurred ; and therefore it is much to be marvelled at that some other explanation was not at least sought for. In September, 1844, before the appointment of inspec- tors of mines, Lyell and Faraday were sent to Haswell Colliery by the Home Secretary to report on an explosion that had just taken place there. I am unable to quote from their official report, but I am firmly convinced that the following sentences taken from their article on the subject in the Phil. Mag. 1845, is the true key to a solution of the problem as regards both the mode of occurrence and means to be used for the purpose of avoiding great explosions in future ; and, moreover, I believe that it has been highly unfortunate, both for the cause of the miner and his employer, that these two philosophers were not induced to prosecute their investigations further than they did. The sentences referred to are these : — " In considering the extent of the fire for the moment of explosion, it is not to be supposed that firedamp is its only fuel ; the coal-dust swept by the rush of wind and flame from the floor, roof, and walls of the works, would instantly take fire and burn, if there were oxygen enough in the air to support its combustion ; and we found the dust adhering to the face of the pillars, props, and walls in the direction of, and on the side towards, the explosion, increasing gradually to a certain distance as we neared the place of ignition. This deposit was in some parts half an inch, and in others almost an inch thick ; 1 it adhered together in a friable coked state ; when examined with the glass it presented the fused round form of burnt coal-dust, and when examined chemically, and compared with the coal itself reduced to powder, was found deprived of the ■greater portion of the bitumen, and in some cases entirely destitute of it." About three years ago JVl. Vital, Ingdnieur des Mines in France, showed that a flame resembling that produced by a blasting shot which blows out the tamping is greatly lengthened in an atmosphere containing a cloud of coal- dust ; and soon afterwards the writer ascertained that air containing a small proportion of fire-damp (less than one per cent, by volume) becomes highly inflammable when coal-dust is mixed with it. These discoveries complete what Lyell and Faraday began, ahd show how explosions of any conceivable mag- nitude may occur in mines containing dry coal-dust. A blasting shot or a small local explosion of firedamp, or a naked light exposed when a cloud of coal-dust is raised up by a fall of roof in air already containing a little fire- damp is sufficient to initiate them, and, when once they are begun, they become self-sustaining. These remarkable facts are either not yet sufficiently well known or their true significance is not yet fully ap- preciated. In conclusion I may state that out of many ' In the reports of the Inspectors of Mines, human bodies, timber, and coal, are described as being charred or burnt where they arc covered with this deposit.— W. G. hundred collieries known to me there is not, to my know- ledge, a single damp one in which a great explosion has happened ; while, on the other hand, there is a con- siderable number of very dry ones in which explosions causing the deaths of from 12 to 178 men at a time have occurred. W. Galloway THE SUN'S PHOTOSPHERE DR. JANSSEN has just made a communication to the French Academy of Sciences, which will be received with interest, not only by students of solar physics, but by all who follow the various triumphs achieved by modern scientific methods. It seems a paradox that discoveries can be made depending on the appearance of the sun's surface by observations in which the eye applied to the telescope is powerless ; but this is the statement made by Dr. Janssen himself, and there is little doubt that he has proved his point. Before we come to the discovery itself let us say a little concerning Dr. Janssen's recent endeavours. Among the six large telescopes which now form a part of the equip- ment of the new physical observatory recently established by the French government at Meudon, in the grounds of the princely Chateau, there is one to which Dr. Janssen has recently almost exclusively confined his attention. It is a photoheliograph giving images of the sun on an enormous scale — compared with which the pictures obtained by the Kew photoheliograph are, so to speak, pigmies, while the perfection of the image and the photographic processes employed are so exquisite, that the finest mottling on the sun's surface cannot be overlooked by those even who are profoundly ignorant of the interest which attaches to it. This perfection and size of image have been obtained by Dr. Janssen by combining all that is best in the prin- ciples utilised in one direction by Mr. De la Rue, and in the other by Mr. Rutherfurd. In the Kew photohelio- graph, which has done such noble work in its day that it will be regarded with the utmost veneration in the future, we have first a small object-glass corrected after the manner of photographic lenses, so as to make the so- called actinic and the visual rays coincide, and then the image formed by this lens is enlarged by a secondary magnifier constructed, though perhaps not too accurately, so as to make the actinic and visual rays unite in a second ■image on a prepared plate. Mr. Rutherfurd's beautiful photographs of the sun were obtained in a somewhat different manner. In his object-glass he discarded the visual rays altogether and brought only the blue rays to a focus, but when enlargements were made an ordinary photographic lens— that is, one in which the blue and yellow rays are made to coincide — was used. Dr. Janssen uses a secondary magnifier, but with the assistance of M. Pragmowski he has taken care that both it and the object-glass are effective only for those rays which are most strongly photographic. Nor is this all ; he has not feared largely to increase the apertures and focal length, so that the total length of the Kew instru- ment is less than one-third of that in operation in Paris. The largely-increased aperture which Dr. Janssen has given to his instrument is a point of great importance. In the early days of solar photography the aperture used was small, in order to prevent over-exposure. It was I^ov. 8, 1877] NATURE 23 soon found that this small aperture, as was to be expected, produced poor images in consequence of the diffraction effects brought about by it. It then became a question of increasing the aperture while the exposure was reduced,, and many forms of instantaneous shutters have been suggested with this end in view. With these, if a spring be used, the narrow slit ' which flashes across the beam to pay the light out into the plate changes its velocity during its passage as the tension of the spring changes. Of this again Dr. Janssen has not been unmindful, and he has invented a contrivance in which the velocity is constant during the whole length of run of the shutter. By these various arrangements the plates have now been produced at Meudon of fifteen inches diameter, showing details on the sun's surface of less than one second of arc. So much for the modus operandi. Now for the branch of solar work which has been advanced. It is more than fifteen years ago since the question of the minute structure of the solar photosphere was one of the questions of the day. The so-called "mottling" had long been observed. The keen-eyed Dawes had pointed out the thatch-like formation of the penumbra of spots, when one day Mr. Nasmyth announced the dis- covery that the whole sun was covered with objects resembling willow leaves, most strangely and effectively interlaced. I here quote from Sir John Herschel.® " According to his observations, made with a very fine telescope of his own making, the bright surface of the sun consists of separate, insulated, individual objects or things, all nearly or exactly of one certain definite size and shape, which is more like that of a willow leaf, as he describes them, than anything else. These leaves or scales are not arranged in any order (as those on a butterfly's wing are), but lie crossing one another in all directions, like what are called spills in the game of spilikins ; except at the borders of a spot, where they point for the most part inwards, towards the middle of the spot, presenting much the sort of appear- ance that the small leaves of some water-plants or sea- weeds do at the edge of a deep hole of clear water. The exceedingly definite shape of these objects ; their exact similarity one to another ; and the way in which they lie across and athwart each other (except where they form a sort of bridge across a spot, in which case they seem to affect a common direction, that, namely, of the bridge itself), all these characters seem quite repugnant to the notion of their being of a vaporous, a cloudy, or of a fluid nature. Nothing remains but to consider them as separate and independent sheets, flakes, or scales, having some sort of sohdity. And these flakes, be they what they may, and whatever may be said about the dashing of meteoric stones into the sun's atmosphere, &c., are evidently the immediate sources of the solar light and heat, by whatever mechanism or whatever processes they may be enabled to develop, and as it were elaborate these elements from the bosom of the non-luminous fluid in which they appear to float. Looked at in this point of view, we cannot refuse to regard them as organisms of some peculiar and amazing kind . . . . " * Here, then, was a discovery with a vengeance ! and absolute endorsement from the man above all others who » I have recently been making some experiments with a view of getting rid of the narrow aperture in general use, as it has appeared to me that the diffraction effects produced by it must be as injurious to definition as those due to a small object-glass. I have found that a circular aperture, allowing the whole beam to be flashed on the plate in conjunction with a plate of optically pure yellow glass nearly ia contact with the photographic plate can he used without over-exposure. 2 " Familiar Lectures," p, 87, had a right to express an opinion. Nevertheless, the organisms have since disappeared, and the work of many careful observers has established that the mottling on the sun's surface is due to dome-like masses, and that the " thatch " of the penumbra is due to these dome-like masses being drawn, either directly or in the manner of a cyclone, towards the centre of the spot. In fact the "pores "in the interval between the domes are so many small spots, while the faculae are the higher levels of the cloudy surface. The fact that faculas are so much better seen near the limb proves that the absorption of the solar atmosphere rapidly changes between the levels reached by the upper faculae and the pores. These masses are in all probability due to a rapid increase of pressure in the portion of the solar atmo- sphere occupied by the photosphere; we know, or think we know, that they are not due to reduction of temperature. Thus much presumed we now come to Dr. Janssen's discovery. An attentive examination of his photographs shows that the surface of the photosphere has not a constitution uniform in all its parts, btit that it is divided hito a series of figures more or less distant fro7n each other, and pre- senting a peculiar constitution. These figures have con- tours more or less rounded, often very rectilinear, and generally resembling polygons. The dimensions of these figures are very variable ; they attain sometimes a minute and more in diameter. While in the interval of the figures of which we speak the grains are clear, distinctly terminated, although of very variable size, in the interior the grains are as if half effaced, stretched, strained ; for the most part, indeed, they have disappeared to make way for trains of matter which have replaced the granulation. Everything indi- cates that in these spaces, as in the penumbras of spots, the photospheric matter is submitted to violent move- ments which have confused the granular elements. In an article recently contributed by Dr. Hunter and myself to the Nineteenth Century^ the following pas- sage occurs : — " The spots may be taken as a rough index of solar energy, just as the rainfall may be taken as a convenient indication of terrestrial climate. They are an index but not a measure of solar activity ; and their absence indi- cates a reduction, not the cessation, of the sun's energy. Whether this reduction means one in a hundred or one in a thousand we do not ktiow." With the same idea in his mind Dr. Janssen points out that this fact throws light upon the forms of solar activity, and shows that that activity, in the photosphere, is always very great, although no spot appears on the surface. We have already referred to the paradox that the sun's appearance can now be best studied without the eye applied to the telescope. This is what Dr. Janssen says on that point. The photospheric network cannot be discovered by optical methods applied directly to the sun. In fact, to ascertain it from the proofs, it is necessary to employ glasses which enable us to embrace a certain extent of the photographic image. Then if the magnifying power is quite suitable, if the proof is quite pure, and especially it I " Sun-spots and Famines," Nineteenth Cenfufy, November, \Zn, p. 584- NATURE [Nov. 8, 1877 it has received rigorously the proper exposure, it will be seen that the granulation has not every vvheie the same dis- tinctness, that the parts consisting of well- formed grains appear as currents which circulate so as to circum- scribe spaces where the phenomena present the aspect we have described. But to establish this fact, it is necessary to embrace a considerable portion of trie solar disc, and it is this which it is impossible to realise when we look at the sun in a very powerful instrument the field of which is, by the very fact of its power, very small. In these conditions we may very easily conclude that there exist portions where the granulation ceases to be distinct or even visible ; but it is impossible to suppose that this fact is connected with a general system. We have written enough to show that when the daily history of the sun comes to be recorded another method and another point of view have now been added as the first fruits of Dr. Janssen's labours in his new observatory. J. Norman Lockyer FOWNES' ''MANUAL OF CHEMISTRY" Fo7vne^ Manual of Chemistry. Vol. 1 1. Chemistry of Carbon Compounds, or Organic Chemistry. Twelfth Edition. By H. Watts, B.A., F.R.S. (London : Churchill, 1877.) ORGANIC chemistry is now progressing with such rapid strides, that a work on this subject becomes antiquated, at least in some parts, in the course of a few years. A new edition of a well known and favourite book must therefore be most welcome to students of this branch of chemical science, and more so when edited by a man whom we may justly call " the English Gmelin." The old familiar, bulky Fownes has now been divided into two handy volumes, enabling the editor to devote the same space to the carbon compounds as to inorganic chemistry. The arrangement of the subject is in principle almost the same as in the last edition ; organic compounds being divided into hydrocarbons, alcohols, ethers, amido-com- pounds,organo- metallic bodies, acids, &c.,the compounds of each group being arranged in homologous series. Physiological chemistry is omitted, and this must be considered as an improvement, as that branch of chemical science now requires special treatment in a separate work. The name of the author is a sufficient guarantee for the soundness of the knowledge which this book imparts, and we hope to see it soon in the hands of numerous students who will find it a most useful and trustworthy guide, embracing as it does the most important recent researches. The book is singularly free from misprints, and the few which we have found can be easily corrected by a student who is accustomed to think for himself. As a reviewer is expected to point out any faults, we will do so, but " sine irae et studia," and only for the benefit of the students who will largely use this work. Thus we miss an account of the normal sulphuric ethers, which are found by the action of sulphuryl chloride, or oxychloride on the alcohols and phenols. Perhaps these parts were written before the researches we allude to were published, and the same may be the case with phenyl-sulphuric acid, and its homologues, compounds which possess such interest both for the chemist and physiologist. To lactide, the author still assigns the old formula C3H4O2, although Henry has proved, by determining its vapour density, that its molecular formula is C6H8O4. On page 285 we find a statement which might lead a beginner in practical work to disappoint- ment, it is there said that '' crude acetyl chloride is purified by heating it with water and dilute soda solu- tion." " Quandoque bonus dormitat Homerus." We were much pleased to find that Mr. Watts has given particular attention to the study of isomerism, especially among the derivatives of benzene, and he justly says in the preface : " This part of the subject is here presented in a form in which it has not yet appeared in any English publication, except in the Journal of the Chemical Society," Speaking of the disubstitution products of benzene, the following definition is given : " A di-derivative of benzene is para-, ortho-, or meta-, according as it can give rise to, or be formed from, one, two, or three tri- derivatives. This definition is, however, incomplete, and only holds good if in the di- derivative the substituting elements or radicals are the same. For it is easily seen that, to take the most simple case, a para-compound containing two different groups such as paranitrobromobenzene can give rise to or be formed from two different amido- nitrobromobenzenes. The oversight is, however, a matter of small importance, and an attentive student will not be led astray by it. The theory of structure or position which Mr. Watts treats so fully has been lately attacked by eminent chemists who seem to overlook or forget the great im- pulse which this theory has given to the progress of organic chemistry. The " modern chemists," as they sneeringly have been called, know well enough that the structural formulte which they use do not pretend to give a picture of the real position of atoms in space, and do not mean more than the parallelogram of forces in me- chanics, i.e., they only express the manner in which the different forces of the atoms attract each other. They fully understand that their present theory, with the pro- gress of science will have to undergo many modifications, and it is not a dogma, but will stand or fall on its own merits. The opponents of the modern school remind us of the last followers of the phlogistic theory who got hold of any fact which the antiphlogistonists were not able to explain as a proof that the latter were in the wrong. We can easily imagine how pleased Priestley was when it was found that when heating certain metallic calces with charcoal an inflammable air was formed, whereas, accord- ing to Lavoisier's school, only carbonic acid could be produced. Just in the same way the opponents of the structural theory point out that the existence of four lactic acids is incompatible with it ; and Mr. Watts himself, although a strong adherent of the theory of structure, shirks the discussion of this point, and rusticates one of the four in a foot-note, in which he expresses his doubts as to its existence. The recent researches of Wislicenus, however, hardly leave any doubt that four such acids exist. We must confess that we are not able to explain the difference between hydracrylic acid and ethenelactic acid, and quite agree with Mr. Watts that Wislicenus' explanation of the ISlov. 8, 1877] NATURE ^5 cause of their isomerism is improvable and far-fetched. But there exist other isomeric compounds which, like these two acids, have apparently the same chemical constitution, and in some of these cases it has lately been shown that the bodies are not chemical isomerides but physical isomorphides, or differ from each other in exactly the same way as calcite differs from arragonite. We have not the least doubt that the cause of the isomerism of the lactic acids will, at no distant time, also find a satisfactory explanation, because we are con- vinced that organic chemistry is working in the right direction. Time will show whether we prophesy truly or not. OUR BOOK SHELF Transcaucasia and Ararat ; being Notes of a Vacation Tour in the Autumn of 1876. By James Bryce. (London : Macmillan and Co., 1877.) Although in this narrative Prof. Bryce takes the reader over pretty well-known ground, about parts of which, at least, much has been written, still even the best-informed readers will read his book with pleasure and profit. Prof. Bryce used his own eyes, and as he is a good and independent observer, there is an unusual freshness about his narrative. He journeyed down the Volga, crossed the southern steppe and the Caucasus to Ararat, which he ascended, thence to the shore of the Black Sea, sailing along the coast to Constantinople. Nijni Novgorod Fair, he thinks, has been much over-estimated in some respects, and he has a good word to say of the recently much- abused Cossack. Prof Bryce is a good geologist, and his work abounds with interesting notes on the geology as well as the flora of the regions which he traversed. Per- haps the most interesting chapter in his book is that in which he describes his ascent of Mount Ararat. In a previous chapter he has collected much valuable informa- tion concerning the mountain, the legends connected with it, its geology, volcanic phenomena, meteorology, vegeta- tion, and animals. Prof. Bryce, with a companion, six Cossack soldiers, and an interpreter, set out from Aralyk, a little to the north of the mountain, at 8 a.m., on September n last year, to attempt the ascent. About noon they were fairly on the side of Ararat, and at about 6,000 feet came upon a small Kurd encamp- ment, some of the Kurds, with their oxen, being induced to act as baggage-bearers. At the well of Sardar- bulakh they camped late in the afternoon, about 7,500 feet above the sea. About one A.M. they started again, thirteen in all, but as they proceeded, with many vexatious halts, the Cossacks dropped off one by one, and at last, at about 12,000 feet. Prof. Bryce resolved to take what he wanted in the way of food, and start at his own pace. Two Cossacks and a Kurd accompanied him to the height of about 13,600 fee^, when they too dropped off, and Prof Bryce resolved to accomplish the remainder of the 17,000 feet alone, a hazardous under- taking even for a trained Alpinist. Partly up a rocky slope which seems to extend considerably beyond the snow-line, and partly over the soft snow itself, and enveloped much of the time in cloud, Prof Bryce continued his solitary and fatiguing climb, until about half-past two p.m., he became convinced that he was really on the top of Ararat, at least one of the tops, for there are two, one about thirty feet higher than the other, and he did not descend until he had set his feet on both. There were difficulties and dangers both in the ascent and descent, though they do not seem to be nearly so great, judging from Prof. Bryce's description, as those which attend the ascent of a moderate Alpine summit. Prof, Bryce reached his companions again in safety. Notwithstanding he had to make all haste to reach the summit, he had time to make several interesting notes of what he saw by the way, the evidences of volcanic action particularly attracting his attention. To show the superstitious awe with which the sacred summit is regarded in the region around, Prof. Bryce tells that when the Archimandrite of Etchmiadzin was told that the English- man had ascended to the top of " Massis," the venerable man replied, smiling sweetly, " No, that cannot be. No one has ever been there. It is impossible." Prof. Bryce's is the sixth known ascent of Ararat, the first having been made in 1829 by Dr. Frederick Parrot, a Russo- German professor in Dorpat University. Thermodynamics. By R. Wormell. (The London Science Class-books. Elementary Series. Long- mans, 1877.) This work is one of the earliest published of a series "adapted for school purposes," and "composed with special reference to use in school teaching," as we are told in the general preface. We feel very strongly that no good can come of the introduction of such subjects as the dynamical theory of heat into school- teaching. That an average school-boy can be taught the elements of such subjects as astronomy, botany, and natural history, and that he will to a certain extent profit by such teaching, may probably be true ; but only in so far as his powers of observation are concerned. We believe that it is a complete mistake in practical education to try to carry the process farther than the elements, even in the case of the comparatively easy subjects just named. Some elementary experimental facts connected with heat might, no doubt, be added to the list. But it is simply the work of the era nmer to stuff a school-boy's head with such utterly unassimilable materials as reversible engines, absolute temperature, and the kinetic theory of gases. This is education run mad. This obvious consideration decides at once our opinion as to the value of the work before us. It is beyond the intelligence of schoolboys, and in the hopeless endeavour to sink it to their level it has been deprived of much that might have made it a serviceable work for more mature minds. After what we have said, it would be superfluous to criticise the book minutely, for nearly all our objections would be mere repetitions in part of the first and general one. We note, however, a want of strictness, or at least of completeness, in some of the mathematical proofs. The first example we meet with may serve as a type. Thus (p. 4) it is assumed, without any attempt at expla- nation, in fact without a word to warn the reader that a distinct step has been taken, that in uniformly accelerated motion the mean velocity during any period is half the sum of the initial and final velocities—a truth, and a very important one, but most certainly not self-evident to the average schoolboy. Simple Lessons for Home Use. (London: E. Stanford, 1877.) These simple lessons are intended for younger children than those for whom the primers published by Messrs. Macmillan have been written, and they appear admir- ably adapted for the purpose they have in view. Mr. W. E. Forster, in his recent speech at Huddersfield, referred to the importance of teaching the elements of science in primary schools by means of appropriate reading books. The little books before us, so far as they go, meet the wish expressed by Mr. Forster. The print is clear, the language on the whole simple, and the price (threepence) places them within the reach of the humblest. Perhaps there is a little too great a tendency to moralise in parts of the otherwise capital little lessons on birds and money. The author of the last-named — the Rev. T. E. Crallan — tells in a simple and interesting way 26 NATURE \_Nov. 8, 1877 how money grows, and writes for younger minds than does the Rev. G. Henslow, who contributes lessons on flowers, where too many technical terms are, we think, introduced, especially in the first chapter. Miss Fenwick Miller's lessons on the human body, and on ventilation, are excellent, and so are Mr. Philip Sevan's on food, and Dr. Mann's on the weather. Altogether, we congratulate the publisher on the subjects selected, and the authors he has chosen : no doubt the remainder of the lessons that are to be issued will confirm the high opinion we have formed of those already before us. W. F. B, LETTERS TO THE EDITOR [The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts. No notice is taken of anonymous communications. The Editor urgently requests correspondents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of com- munications containing interesting and novel facts.'\ Appunn and Koenig. — Beats in Confined Air In my letter published in Nature (vol. xvi. p. 227), I stated that I should re-examine the question of the discrepancy between Appumi and Koenig, and inform you of the result. During the whole month of September I was engaged in very carefully counting and recounting Appunn's tonometer in the South Ken- sington Museum, the reeds of which had got a little out of order, a circumstance which did not interfere with the ascertainment of pitch, but disposed at once of any errors in Appunn's pendulum. I employed one of Webster's ship chronometers, which was rated to lose one second daily, and counted each set of beats repeatedly through one or two minutes. I ascertained by this means that the objections made by Koenig on the score of false pendulums and false counting were entirely groundless, and that the former determinations of the relative pitch of Koenig's forks and Appunn's reeds, made by Dr. Preyer and myself, were prac- tically correct. But as Lord Rayleigh pointed out in Nature (vol. xvii, p. 12) the practical agreement of the results obtained by Professors Mayer and MacLeod, and by his own new method there de- scribed, with Koenig's, serves to show that there is a physical phenomenon to be accounted for. Mr. Bosanquet had drawn my attention to the subject several months ago, and my own experiments on the beating of disturbed consonances had led me to the same conclusion. Accordingly I had devised a series of experiments for ascertaining the fact, the nature of which I lately communicated to Lord Rayleigh ; but as they required the use of two tonometers excited by separate bellows, there were difficulties in the way of making them, which I did not overcome till this week. To-day I made the first of these experiments, lasting four hours or more, and ascertained — 1. That the beats of the harmonium reeds in Appunn's tono- meter are affected by taking place in a confined space of air. 2. That they are accelerated, and 3. That the acceleration, being roughly about one per cent., will probably, when completely ascertained, account for the discrepancy observed. Details have been sent privately to Lord Rayleigh ; they are too incomplete for publication. The experiments will require many weeks to complete with the necessary accuracy. But in the meantime I hasten to communicate an important acoustical fact which may bear upon many other phenomena besides the ascertainment of absolute pitch. Alexander J. Ellis 25, Argyll Road, Kensington, November 3 The Radiometer and its Lessons As I now learn for the first time what are the grounds on which Prof G. C. Foster based his inculpation of me, I may ask for a very few last words. I fully admit that in giving a sketch of the history of the Radiometer, I intended to attribute to Mr. Crookes that he had in the first instance put a wrong interpre- tation upon his own results ; because I believed that this was a simple fact, well knovm to everybody who had followed the history of the inquiry. And Prof. Carey Foster has not called in question the correctness of my statement of the general im- pression which prevailed among scientific men, alike when Mr. Crookes first exhibited his radiometer at the soiree of the Royal Society, and when its phenomena were discussed at the subse- quent meeting. Having fol'owed that discussion with the greatest interest, I cannot now recall one word that was not in harmony with the "direct impact" doctrine, or that suggested the idea of " heat reaction " through residual gas. If the question had been then asked, whether the rotation would continue to take place in an open vacuum (were such possible), or in a per- fect vacuum, — so as to eliminate all " reaction," through residual gas, between the vanes and the containing flask, — I believe that the general, if not the unanimous, verdict would have been in the affirmative. Certainly I heard nothing from Mr. Crookes on the other side, he having previously spoken of the dependence of the "Repulsion resulting from Radiation on the presence of residual gas as 'impossible to conceive.' " It is clear, then, that in referring to this then prevalent view, I no more wished to put Mr. Crookes in the wrong, than I wished to put in the wrong my very excellent friends among the other eminent Physicists who shared it ; the special purpose of this part of my paper being to bring out, as strongly as I could, the thoroughly scientific and philosophical method in which Mr. Crookes aftenuards worked himself right. If this is not expressed in as much detail as Prof. G. C. Foster would have approved, it surely afforded no adequate ground for his going out of his way to charge me with having "depreciated Mr. Crookes's merits." Yet this is the only ground that I can find in the whole of Piof. Carey Foster's statement, for what I could not but regard as a very grave imputation. On Mr. Crookes's reply I shall make but a single remark, witli reference to his perfectly correct citation of the latter part of my conversation with him, on the occasion of his receiving the Royal Medal. If I had not found, afier the publication of my Lectures (in which I said nothing but what wfs respectful to Mr. Crookes), that he had himself been "digging up the hatchet" which 1 was quite disposed to keep buried, by giving his public attestation to the "spiritualistic" genuineness of what had been proved to be a most barefaced imposture, I s-hould not have again brought his name into the controversy. But I felt that his yrtatly increased reputation as a Scientific man would do an increasing injury to what I honestly believed to be the cause ot reason and common sense, not only in this country but still more in the United States. Since the death of Prof. Hare, not a single scientific man cf note (so far as I am aware) has there joined the Spiritualistic ranks; but the names of the "eminent British scientists," Messrs. Crookes and Wallace, are a " tower of strength " to the various orders of "mediums" — rapping mediums, writing mediums, drawing mediums, materialising mediums, test mediums, photc- graphic mediums, trance mediums, healing mediums, and the like — zvhose names form many columns of the " Boston Trades' Directory." And the now notorious impostor, Eva Fa}', has been able to appeal to the " endorsement " given to her by the " scien- tific tests" applied to her by "Prof. Crookes and other Fellows of the Royal Society," which had been published (I now find) by Mr. Crookes himsell in the Spiritualist in March, 1875. Within two months of that date, as Mr. Maskelyne has publicly stated, an offer was made him (I have myself seen copies of the letters) by Eva Fay's manager, that for an adequate sum of money the *' medium " should expose the whole affair, scientific tests and all, '\complicating at least six big guns, the F.R.S. people,''^ as she was not properly supported by the Spiritualists, I have therefore felt it incumbent on me to show that in dealing with this subject Messrs. Crookes and Wallace have followed methods which are thoroughly ««-scientific ; and have been led by their " prepossession " to accept with implicit faith a number of statements which ought to be rejected as completely un- trustworthy. My call to take such a part — which I would most gladly lay aside for the scientific investigations which afford me the purest and most undisturbed enjoyment — seems to me the same as is made upon every member of the Profession to which I have the honour to belong, that he should do his utmost to cure or to mitigate bodily disease. The training I originally received, and the theoretical and experimental studies of forty years, have given me what I honestly believe (whether rightly or wrongly) to be a rather unusual power of dealing with this subject. Since the appea-ance of my Lectures I have received a large number of public assurances that they are doing good service in preventing the spread of a noxious mental epidemic in this country ; and I have been privately informed of several instances, in which persons who had been " bitten " by this malady, have owed their recovery to my treatment. Looking to the danger which threatens us from Nov. 8, 1877] NATURE 27 the United States, of an importation of a real spiritualistic mania, far more injurious to our menial welfare, than that of the Colorado beetle will be to our material interests, I should be untrue to my own convictions of duty if I did not do what in me lies to prevent it. That I do not take an exaggerated view of the danger, will be obvious to any reader of Mr. Home's book. I know too well that I thus expose myself to severe obloquy, which (as I am not peculiarly thick-skinned) will be very un- pleasant to myself, and unfortunately still more so to some who are nearly connected with me. But I am content to brave all, if I can believe that my exposi will be of the least service either to individuals or to society at large. VV. B. Carpenter The high scientific position which Prof. Foster holds, as well as the decided manner in which his letter was written, must lead the otherwise unbiassed reader to the conclusion that not only has a satisfactory explanation of the action in question been found and generally adopted, but that this explanation turns upon certain considerations, and particularly on the mean length of the path of the gaseous molecules as influenced by the degree of rarefaction. I feel my position, therefore, particularly unfortunate in having, for the sake of truth, to show that the explanation which Prof. Foster has adopted, and supposes others to have adopted, is, if judged by the statements in his letter, inconsistent with well-established laws. Prof. Foster gives me credit for having originated the funda- mental idea of the explanation, but states that my "explanation was theoretically incomplete ; in particular it did not show clearly why so high a degree of rarefaction should be necessary for the production of the phenomenon in question ; " and then he proceeds to explain how this asserted deficiency was supplied by other thinkers, who showed that "the increase, resulting from rarefaction, in the mean length of the path of the gaseous molecules, would favour the action." It is this supposed completion of my explanation that is erroneous. It is contrary to the law of the diffusion of heat in g3ses ihat "the increase, resulting from rarefaction, in the mean length of the path of the gaseous molecules would favour the action," and so far from supplying any deficiency in my explana- tion it is incompatible with it. The only result from such an increase is to diminish the action — a result which rises into importance only when the rarefaction is carried so far that the mean length of the path of a molecule becomes comparable with the dimensions of the inclosing vessel. In my first paper I gave a definite proof, which has nowhere been questioned, that according to the kinetic theory the force arising from the communication of heat from a surface to adjacent gas of any particular kind depends only on one thing, the rate at which heat is communicated, and to this it is proportional. If therefore the increased rarefaction increased the f r -e it must increase the rate at which heat is communicated, but accor^hng to the law established by Prof. Maxwell the rate at which heat is communicated is independent of the density of the gas, whence it follows tbat the increase in the mean length of the path of the gaseous molecules, resulting from rarefaction, cannot favour the action which remains approximately constant until the gas becomes so rare that the law of diffusion no longer holds, alter which it may easily be shown the communication of heat, and hence the action in question, diminishes but never increases. The fact that in the radiometer the force caused by the com- munication of heat only causes motion when the surrounding gas becomes extremely rare is, as I pointed out in my first papers, fully explained by the action of what I have called con- vection currents, which action depends on the weight and density of the gas. The gas adjacent to the hot surface is hotter than that which is more remote, and hence the former rises form- ing an ascending column, to supply which the gas is drawn in laterally on all sides, and tends to carry the surface forward with it. With the same difference of temperature and surround- ing circumstances the speed of these convection currents is the same whatever may be the density of the gas, and hence the force which they exert on the surface is proportional to the density of the gas. This force is opposite in direction to that arising from the communica ion of heat to the gas, and since the former dimi- nishes with the density while the latter is constant, there must be some density for which they balance, and below which the constant force will predominate, while above this point the con- vection currents will carry the surface with them. The fact that, starting from low densities, the motion of the vanes in the radio- meter does not only diminish as the density increases, but is actually reversed at higher densities, requires explanation, and no other than this has yet been offered. I have gone into the subject at considerable length, as I felt bound, when venturing to differ from so high an authority as Prof. Foster, to state my reasons. There is, however, nothing in what I have said here which I have not said elsewhere, in the same or other words ; and however incomplete in theory the explanation given in my first papers may be, I can only say that it included all the facts known to me at the time these were written ; it has led me to predict many of the experimental results which have since been obtained, and I have not been able to find one fact with which it is not in accordance, nor has it been, so far as I am aware, controverted in any particular. Osborne Reynolds Potential Energy I HAVE reason to believe that the "grievous error" with which I charged "John O'Toole " in his reference to the clock is not meant by him to be his own view of the matter at all, but merely a legitimate deduction from the confused and inconsistent language of " the doctors." Such an erroneous view on his part is, indeed, obviously out of harmony with the extensive know- ledge of the subject of energy displayed by him in letters which, without doubt, will convince " the doctors " of the necessity of adopting consistent and strictly logical phraseology. G. M. MiNCHIN Royal Indian Engineering College, Cooper's Hill Effects of Urticating Organs of Millepora on the Tongue An article by Mr. Moseley, in Nature (vol. xvi. p. 475), reminds me of an experiment I made some years ago in Florida. In collecting corals on the reefs, I had of course become familiar with the disagreeable, though not very painful, effects of contact of the hands with Millepora. But the vulgar names of Pepper-coral or Sea ginger induced me to try the effect on the tongue, to find out how far the taste resembled those condi- ments. I accordingly broke off a fresh piece and applied it to the tongue. Instantly a most severe pain shot, not only through that organ, but also through the jaws and teeth. The whole course of the dental nerves and their ramifications into every single tooth could be distinctly and painfully lelt. I can com- pare the sensation to nothing better than to the application of the poles of a pretty strong galvanic battery. The pain re- mained severe for about half an hour, then became duller, leaving a sensation still perceptible five or six hours later. The whole impression was much too violent to allow the distinction of any particular taste. Such an experiment made with Physalia might be positively dangerous, considering the much more powerful urticating effects of its polyps. Indeed, a friend of mine once related to me that when a boy he had come in contact with one of the long tentacles of a Physalia, when bathing, and had to be carried out of the water almost fainting. L. F. Pourtales Cambridge, Mass., October 22 Drowned by a Devil Fish The following account of the destruction of a human being by a cuttle fish at Victoria, in Vancouver Island, has all the appear- ance of authenticity about it. It occurs in the Weekly Oregonian of October 6, 1877. The Oregonian is the principal paper of Oregon, and is published at Portland. The insertion of the account in Nature may lead to further information on the subject. I know of no other authentic instance of the kind. An account of the habits of the huge octopus of the Vancouver Island Sounds and also of the Indian method of hunting and killing the beasts for food is to be found in John Keast Lord's "Naturalist in Vancouver Island and British Columbia," vol. i. p. 192. Mr. Lord measured specimens which had arms five feet in length, with a thickness at their base as great as his wrist, and he once collected a detached sucker of one of these cephalopods as large as an egg cup in mistake for a huge actinia. NATURE \lSlov.Z, 1877 " British Columbia ' ' Drcnuned by a Devil Fish " Victoria, September 27. — An Indian woman while bathing was pulled beneath the surface of the water by an octopus or devil fish and drowned. The body was discovered the following day in the bottom of the bay in the embrace of the monster. Indians dived down and with their knives severed the tentacles of the octopus and rescued the body. This is the first recorded instance of death from such a cause in this locality, bat there have been several narrow escapes." Exeter College, Oxford H. N. Moseley The Earthworm in Relation to the Fertility of the Soil In Nature, vol. xvii., p. 18, there is an account under the above heading of M. Hensen's investigations of this subject, to which I wish to add a note. He says the assertion that the earth-worms gnaw roots is not proved by any fact ; roots gnawed by worms were never met with by him, and the contents of the intestines of the worms never included fresh pieces of plants. The experience of gardeners that the earth-worm injures pot plants may be based on the uncovering or mechanical tearing of the roots. I should have thought that the universal experience of gardeners is that earth-worms never eat vegetable matter until it has decayed, and that their instinct leads them to draw the points of leaves as far as they can into their tubes for the purpose of setting up the decaying process, and likewise to sever the roots of pot plants with the same object. I can hardly under- stand how earth-worms have any mechanical means of severing the roots of plants except by gnawing. But there is an omission in M, Hensen's account of the ferti- lisation of the subsoil by earth-worms which surprises me. He mentions but two ways in which this is effected, viz., by the opening of passages for the roots into deeper parts, and by the lining of these passages with humus. I thought it was a well-known fact that worms, by means of their "casts," effect a complete renversement of the soil of meadow land down to a certain depth in the course of a few years. But whether wdl-known or not I met with a demon- stration of this important fact in 1857. When putting down a considerable extent of iron fencing iu the alluvial meadows near my house (consequent upon an exchange of land) I had occasion to cut a ditch two or three feet deep, and when the workmen had finished the ditch — a quarter of a mile long in all — I was astonished to see in one portion, of about sixty yards in length, a distinct and very even narrow line of coal-ashes mixed with small coal in the clean cut surface of the fine loam of the ditch face, per- fectly parallel with the top sward. It immediately occurred to me that this was the work of the earth-worms, and upon inquiry I found that the farmer, who had occupied this land for many years, remembered having once, and only once, carted out some coal-ashes and spread it at this spot not many years before. I forget the exact number of years, but I believe it was about eighteeen. I have a distinct recollection, however, that the depth of the line of coal-ashes below the surface was at least seven inches, and that this seemed to confirm the general belief that the depth to which the earth-worm usually burrows is about that amount. I may add that the colour of the loam above the line of coal-ashes was decidedly darker than of that below. Henry Cooper Key Stretton Rectory, Hereford, November 2 In Nature, vol. xvii. p. i8, some details are given of observations made by M, Hensen on the relation of the earth- worm to the fertility of the ground. He has observed, as everyone must have observed, that the earthworm during night draws into its tube or hole the loose leaves and fibres which may be lying about. But this operation of the earthworm has a significance in relation to the vegetable world of even a pro- founder kind than that of the fertilisation of the soil. Some months ago, in searching for young ash plants with three cotyledons, I found that in a great many cases the samara or seed of the ash had been drawn into a worm's hole, and had there found moisture and other essential conditions of growth ; while the same seeds lying dry upon the surface had not germi- nated. There can thus be no doubt that many seeds of all kinds are drawn under the surface of the ground, or covered by the earth thrown up by worms. They are thus preserved from birds and various enemies, and are placed in the proper position for germination. The dead plant is perpetuated from its fallen panicle by the earthworm. An ash tree, or a whole forest of ash trees, may have been planted by earthworms. North Kinmundy, November $ A. Stephen Wilson M. AUuard's Condensing Hygrometer The notice of the above instrument in last week's Nature (p. 14) is an excellent illustration of the necessity for increased communication between the scientific men of all countries. The labour which is at present wasted by repeating what has been done before is enormous, and until international intercommuni- cation is improved it must be so. I quite agree with you in your appreciation of M. AUuard's hygrometer, but I think it is desirable to state that it is not the first in which "the part on which the deposit of dew is to be observed is a plane well-polished face a, of silver or gilt brass." The annexed engravings represent the form of plane- faced hygrometer invented by Mr. G. Dines, F. M.S., described by him in the Meteorological Magazine for October, 187 1, and exhibited at the Brighton Meeting of the British Association, 1872. The action is extremely simple ; no ether is required nor any aspirator. Water colder than the dew point is the only requisite — it is poured into the reservoir A, passes through the regulating- tap B into the chamber D ; it is, by the black diaphragm, thrown past the bulb of the thermometer c, and then allowed to escape. The cooled plane surface E of silver or black glas=, is excessively thin, and the space between it and the thermometer-bulb is wholly occupied by the effluent water, so that the great essent'al Section of all hygrometers, a true indication of the temperature of the cooled surface, seems to be reached. The plate e can be kept within o°'2 or o°'3 for a length of time by adjusting the screw B, and as the condensation usually takes an elliptical form over the thermometer-bulb, and in the middle of e, the advantage of an adjacent bright surface is usually attained. I am, hov/ever, not sure that M. AUuard's surrounding plate might not be a con- venience, although for the reason above given I have not found it necessary. G. J. Symons 62, Camden Square, N.W., November 2 Optical Spectroscopy of the Red End of the Solar Spectrum Nature, dated August 2 (vol. xvi. p. 264), containing Pro*". Piazzi Smyth's communication on " Optical Spectroscopy of the Red End of the Solar Spectrum," reached me on the 2ist ult., when I had no leisure to avail myself of the outgoing mail and reply immediately to the subject of his last paragraph. Inquiry is there made of "anyone" (besides the Royal Society), in association more or less with my name, whether more recent particulars have been published, of the spectrum in question, than "those {i.e. my) Indian observations," "printed in the Philosophical Transactions so long ago as 1874" {i.e. 1875). 2. The Astronomer- Royal for Scotland is presumably in a better position to reply for "any one," than myself, located in latitude N. 30°, longitude E. 78° ; and so far as the inquiry relates to the Royal Society, his penultimate paragraph in itself furnishes the information sought, because the Society's publica- Nov.Z, 1877] NATURE 29 tion prominently alluded to by himself is the last publication. As respects myself, I have printed no further particulars in addition to tho^e wh'ch the Professor (lismis^es, briefly for the present, with the announcement of having discovered, "total contradic'ions" to certam "conspicuous features." 3. It i* necessary to point out, that the designation for my observations adopted by the Professor of "the Royil Society's and Mr, Hennessey's high-sun seres" suggests existence of the a'iZ'/(/rt/ responsibility wh'ch is plainly disav()weit and sing on the edge of the table and allow Us to go quite near to it without ceasing its warble ; one of its favourite haunts was the wood basket, and it would often sit aad sing on the edge o( it. On Fetiruary 12, the last night of the carnival, we had a number of fi lends in our salon, and the little mouse sang most vigorously much to their delight and astonishment and was not in the least disturbed by the talking. In the evening the mouse would often run about the room and under the door into the corridor and adjoining rooms and then return to its own hearth ; after amusing us f^r nearly a month it disappeared, and we suspect it was caught in a trap set in one of the rooms beyond. The mouse was small and had very large ears, which it moved about much whilst singing ; the song was not unlike that of the canary in many of its trills, and it sang quite as beautifully as any canary, but it had more variety, and some of its notes were much lower, more like those of the bullfinch. One great peculiarity was a sort of double song, which we had now and then — an air with an accompaniment ; the air was loud and full, the notes being low and the accompaniment quite subdued. Some of our party were sure that there was more than one mouse until we had the performance from the edge of the wood basket, and were within a yard or two of it. My son has suggested that many or all mice may have the same power, but that the notes are usually so much higher in the scale that, like the cry of the dormouse and the bat, they are at the verge of the pitch to which the human ear is sensitive; this may be so, but the notes of our moue were so low and even the highest so far within the limits of the human ear, that I am inclined to think the gift of singing in mice is but of very rare occurrence, Joseph Sidebotham Hotel de Menton, Menton, S. France, October 31 Several years ago I received some of these animals from a fritni, and kept them in confinement for one or two months. The description which your correspondent gives of their per- formance leaves very little to be added by me, as in all respects this de-cription agrees perfectly with my own observations. I write, however, to remark one curious fact about the singing of these mice, namely, that it seemed to be evoked by two very o^ipo-itc sets of conditions. When undisturbed, the lit le animals Used for the most part to remain quiec during the day, and begin to s ng at night ; but if at any time they were alarmed, by handl ng them or otherwise, whether during the day or night, they were bure to sing vigorously. Thus the action seemed to be occasioned either by contentment or by fear. The character of the song, however, was slightly diff rent in the two cases. Tnat t*iese mice did not learn this arc from singing birds there can be no doubt, for they were captured in a house where no snch birds were kept It may be worth whi'e to add that thus house (a London one) scf-med to ha>'e been suddenly invaded, sotospetk. by a number of these animal-, for although my friend has lived in this house since the year 1862, it was only during a few months that singing mice were heard in it, and during these Jew months th-y were heard in considerable numbers. Regent's Park, November i George J, Romanes Meteor The following accottnt of a meteor seen here may perhaps interest some of your readers : — On October 29, at 8h, im, 30s. Greenwich mean time, a brilliant meteor exoloded in right ascension 268'', declination -1- 60° (equator of 1855) ; it left a bright crooked train scarcely half a degree long, wh ch remained visible for about ten seconds, and pointed towards | Draconis. The course of the meteor must have been directed downwards, a'most exactly towards this observatory. The flash of the explosion was seen by the assistant-astronomer, Mr. Lohse, although he was sitting in such a position as to be unable to see the meteor directly. Lord Lindsay's Ob^ervatory, Ralph Copeland Dnnecht, Aberdeen, November 3 INTERNATIONAL POLAR EXPEDITIONS IN February, 1875, when the Arctic Expedition was being prepared, I asked the First Lord of the Admiralty, in Parliament, whether, in view of the small value for scientific purposes of isolated observations in the Arctic regions, in comparison with simultaneous observations at different pUces, and in view, also, of the interest now taken in Arctic science by foreign Govern- ments, he would postpone fjr one season the departure of the proposed Arctic Expedition, and in the interval communicate with foreign Governments with a view to the organisation of other expeditions to make observa- tions simultaneously with our own at fixed times.'' The First Lord said that he considered the preparations for an expedition too far adv^anced to admit of this, and added : " I should regard the project of combination with other powers to attain the objects in view as one beset with difficulties "—in which, I think, he was in error. In the following month, when the Supplementary Estimate for the Arctic Vote was under discussion, I again drew the attention of the Governmerit and Parliament to the advantages of simultaneous Arctic expeditions (see Hansard, voL ccxxii. p, 1354), and in Naval Science for April of the same year, in an article on " Foreign Polar Expeditions," I drew still further attention to the matter, concluding with an extract from a paper by Capt. Weyprecht (who so greatly distinguished himself in the Austro- Hungarian polar expeditions of 187 1 and 1872-74), in which he pointed out in the clearest manner the desira- bility of extending future Arctic researches far bayond mere geographical exploration, and pressing forward with our studies of magnetis-n, electricity, the best of meteoro- logy, &c. " The solution of these questions cannot," he said, " be expected until all nations which claim to come up to the present high standard of civilisatiori unite to go hand in hand, setting aside all national rivalries. To bring about decisive scientific results it will be necessary to make a number of simultaneous observations, so con- ducted that they will furnish a yearly resumi of observa- tions made in different parts of the Arctic regions with exactly similar instruments, and from exactly similar instructions," Upwards of a year ago NATURE gave details ot Wcy- precht's project for the scientific exploration of the Polar regions. It was referred to on several occasions, and pointed out that Weyprechi's plan was the only satisfactory method of obtaining results of real and peimanent value, C2 30 NA TURE [Nov. 8, 1877 The programme has now been extended and completed, and was prepared for submission to the International Meteorological Congress which was to have met at Rome in September, but which has been adjourned to next year. I have just received from my friend Weyprecht a copy, and may summarise its contents as follows : — The enterprise proposed by Count Wilczek and Capt. Weyprecht has for its aim strictly scientific exploration, purely geographical discovery being a secondary matter. It will be the first step towards a systematic scientific investigation of the regions around the poles of the earth and the minute observation of phenomena pecu- liar to these regions — phenomena the earnest investi- gation of which is of the highest importance in con- nection with a great number of problems with regard to the physics of the globe. The international expedi- tion will have for its aim to make in the Arctic and Antarctic regions, or in the neighbourhood of these regions, and at as many stations as it is possible to establish, synchronous observations according to a pro- gramme mutually agreed upon ; for the purpose, on the one hand, of deducing by comparison from observations collected at different points, independently of the pecu- liarities which characterise the years of different obser- vations, the general laws of the phenomena investigated ; and, on the other hand, of arriving by probable induc- tions at a knowledge of the chances of penetrating further into the interior of the unknown regions. For this purpose each of the states participating in the work will undertake to equip at its own expense, and send out an expedition to one of the points designated. Each state will of course be at liberty to authorise its ex- pedition to carry on work outside of that mutually agreed on. The investigations to be made in common bear only on meteorological phenomena, those of terrestrial mag- netism, aurora borealis, and on ice phenomena. At each station the observations must be continued one year, from September i to August 31. The meteorological observations will be made in conformity with the resolu^ tions of the permanent International Committee, and will relate to atmospheric pressure, the temperature and humidity of the air, the direction and force of the wind, the state of the sky and its degree of clearness, and also to phenomena of condensation. The programme then gives detailed instructions as to methods and instruments of observation, all being arranged to secure accuracy, fulness, and uniformity. It is probable that each station will be near a coast, and one of the chief objects of the expedition will be to observe the connection between the movements of the ice and the winds and currents, and if these are observed regularly, important results will no doubt be obtained as to the movements of the ice in the Arctic regions, and therefore as to the routes most favourable for reaching the pole. The best ice-observations will of course be at those stations where local conditions have the least influence. The magnetic observations are divided into absolute determinations and determinations of the three elements. Minute directions are given in the programme as to the method to be followed in taking these observations, the fixing of the positions of the various instruments, the kinds of instruments to be used, the methods of verification and testing, the construction of observatories, &c. These directions, if faithfully carried out, would give the ob- server plenty of work to do, but the result would be of unprecedented value. In consequence of the per- sistent perturbations which prevail in these regions, isolated readings made only from hour to hour, even when carried on for long periods, are not sufficient to give with precision the hourly, daily, and monthly magnetic character of the place of observation. It is necessary, consequently, to multiply these observations. Ten obser- vations per hour for each of the three elements will be sufficient, and to injure a rigorous synchronism it is stipulated that the three instruments of variation be read during ten minutes, from minute to minute, viz., at the full minute (— h. 56m. os.) the declination, ten seconds after (— h. 56m. los ) the horizontal intensity, and ten seconds after that (— h. 56m. 20s.) the inclination. Before and after each observation, viz., — h. 52m. 03., and at — h. 69m. OS. the form and position of the auroras should be noted. Immediately after the meteorological observations should be proceeded with in the following order : — Temperature, humidity, winds, clouds, atmo- spheric pressure. (For magnetic observations it is proposed to use Gottingen mean time.) Besides obser- vations of the regular magnetic variations, it will be of great importance to have made, by three observers, rigidly synchronous readings of the three elements in order to obtain precise data of the total intensity. For this purpose there will be made, during one hour each day, by these observers, from minute to minute, from — h — m. OS., readings of the three instruments. The hours of these observations should be advanced an hour each day, so as to return to the point of departure at the end of every twenty-four days. The aurorae should be observed as to their form, their intensity, and their position. The programme then names and describes the various forms assumed by aurorae — arches, streamers, beams, corona borealis, haze, waves, flashes — for the adequate and scientific observation of which the programme gives directions. The most favourable time for this joint expedition will be October and November, when the temperature is not so low as to necessitate special preparations. As the absolute simultaneity of the observations is of the utmost importance, each station must be furnished with the means of obtaining the exact longitude ; good chronometers will also be necessary. To carry out the above observations to their fullest extent, four observers will suffice for each station, if among the subordinates there are men who can perform the purely mechanical duty of reading the instruments. The programme concludes with three propositions, the purpose of which is to insure the possibility of the exact comparison of the magnetic observations. The following are the points proposed as most favour- able for the various observations referred to above :— In the northern hemisphere — The north coast of Spitz- bergen ; north coast of Novaya Zemlya ; Finmark, near the North Cape ; the mouth of the Lena, on the north coast of Siberia ; New Siberia ; Point Barrow, on the north-east of Behring Strait ; the west coast of Green- land J the east coast of Greenland, about 1^ N. lat. In the southern hemisphere — The neighbourhood of Cape Horn ; the Kerguelen or Macdonald Islands ; one of the groups south of the Auckland Islands. I wish that in the influential pages of Nature this great international scientific subject could be agam urged. I cannot help thinking that in the present Hydrographer of the Navy we have an officer who would be at once most able and willing to take part in giving, in the way suggested, true scientific direction and scope to future Arctic research. My confidence in the g'Cat value of simultaneous observations in comparison with the meagre results of isolated expeditions must be my apology for thus writing, E. J. Reed THE NORWEGIAN DEEP-SEA EXPEDITION FROM soundings taken by the second German Polar Expedition, and kindly communicated by Capt. Koldewey, of Hamburgh, I have been induced to alter l^ov. 8, 1877] NATURE 31 my views about the configuration of the sea-tottom | around Jan Mayen. Tl^ ^gure of the bottom which I at present find the most probable I have given in the chart which I send herewith. It will be observed that it is the pait of the sea between Jan Mayen and Ice- land which is to be corrected on the small chart which was published in NATURE, vol. xvi. p. 527. Christiania, October 23 H. Mohn ON THE DIFFUSION OF MATTER IN RELA- TION TO THE SECOND LA W OF THERMO- DYNAMICS I. nPHE purpose of this paper is to call attention to a ■^ natural process that appears to constitute an exception to the second law of thermodynamics, and which, if noticed by others, would at least appear from its importance to merit a rr.ore general recognition. The subject may be best dealt with by means of a simple illustration, the principles involved in the action of which are already perfectly well known. 2. Let the annexed figure represent a cylinder, contain- P 0 H ing a piston, p ; a suitable (plumbago) porous diaphragm (as used for diffusion experiments) being fitted into the piston. The piston can be connected conveniently with any outer arrangement for doing work. Suppose the one half of the cylinder to be filled with oxygen, the other half with hydrogen. Then, as is known, according to the kinetic theory, the molecules of O and H are im- pinging continually against the porous partition or diaphragm, P, and the molecules in their impacts thus occasionally encounter vacant spaces or pores, and so continue their motion on across the diaphragm into the opposite compartment. Owing, however, to the fact that the molecules of hydrogen are moving four times as fast as the molecules of oxygen, they strike the diaphragm correspondingly more frequently, and thus four times as many hydrogen molecules pass through into division O, as oxygen molecules pass through into division H. [The piston is supposed fixed at present, so that no work being done, there is consequently no heating or cooling of the gas.] But on account of the excess of molecules passing into division O, the pressure there will rise. If, then, after the pressure has risen to a certain degree, the piston be 32 NATURE {Nov. 8, 1877 suddenly released, it will be driven by the excess of pres- sure in the direction O H, and in that act the gas in O will be chilled and the gas in H heated, which is contrary to the second law of thermodynamics, since in this process work is derived from matter all at a uniform temperature, or work is derived by cooling a portion of gas below the coldest of surroundzns^ objects. In the same way the piston might have been connected to some external mechanism, and so part of the work be done externally (in a self-aciing manner). 3. There can be little doubt that such work is done in natural processes (in the animal and vegetable world) since plants and organic tissues are distinguished fjr their porosity, 3ind such tissues are permeated with the various gases of the atmosphere, carbdnic acid, &c. It may be observed that even without any porous diaphragm at all, or when two gases whose molecules possess dif- ferent velocities are allowed to diffuse into each other, there is invariably a transferenr e of heaf, which is con- trary to the second law of thermodynamics, which law assumes that heat cannot pass between two bodies origi- nally at the same temperature, or heat cannot pass from a colder to a hotter body. Yet it is evident that as soon as the heat has begun to pass from one of the diffusing gases to the other, the one from which the heat com- mences to pass is already the colder. 4. Such a principle is evidently capable of an enor- mously wide application in nature. It is only necessary for example for the constituents of the universe to be diverse, to get any amount of work by diffusing them together, even if all originally at the satJte temperature. The principle Gi the tendency to the uniform diffusion of Matter, is capable of completely overthrowing the tendency to the uniform diffusion of Etiergy ; for even if energy were uniformly diffused, the uniformity could be upset by the diffusion of matter {i.e. provided matter were not already all uniformly diffused or homogeneous) : and, as we have seen, the quantity of work to be derived by the diffusion of matter is limited only by the quantity of matter at disposal.^ In order that all capacity for work might cease in the universe, it would be necessary not only that there should be a uniform diffusion of energy, but also a uniform diffusion of matter. Heterogeneity confers a capacity for work, as well as inequality of tem- perature. Heterogeneity, as far as is known, is one of the distinguishing characteristics of the material universe. Any dissimilarity of molecular mass, which (by equality of temperature) is necessarily attended by dissimilarity of molecular velocity, confers a capacity for work. The dis- similarity of velocity is evidently the efficient cause in determining the work, and therefore in the exceptional case where dissimilarity of molecular structure is not attended by inequality of mass (and consequently not by inequality of velocity), work could not be derived. We may note, therefore,. that inequality of molecular velocity, as well as inequality of molecular energy, confers a capacity for work, and in order that all capacity for work should cease, not only must molecular energy, but also molecular velocity be uniformly distributed, or the mole- cules of matter which (by equality of temperature) possess unequal velocities, must be uniformly diffused. 5. We may observe that gravity which does not inter- fere with the uniform diffusion of energy, does interfere with the uniform diffusion of matter. Thus, for ex- ample, the energy (heat) of the atmosphere, tends to be uniformly diffused throughout a vertical column of the atmosphere, in spite of the action of gravity. But the uniform diffusion of matter {i.e., the uniform mixture of the gases of the atmosphere through each other) is pre- vented by gravity. For by the well-known law of Dalcon ' Since the first draft of this paper was written, I have been informed that the question ot the quantity of work to be derived by diffusing gases has been treated of by Lord Rayleigh (^Phil, Mag, April, 1875;, but he does not apparently mention the bearing of the case on the sec6nd law bf thermo- dynamics. (>vhich accords with the result of the kinetic theory of gases), each gas arranges itself as a layer upon the earth's surface, precisely as it would do if no other gas were present. Thus (as is known), owing to s^the fact that a greater quantity of nitrogen exiss in the atmo- sphere than oxygen, the nitrogen consequently rises to a greater height than the oxygen, so that at considerable heights the nitrogen predomina'es. Thus the uniform diffusion of the constituents of the atmosphere through each other is prevented by gravity. It may, perhaps, be just as well to note in connection with this point that those gases which are observed at the surface of nebulas are not necessarily at the surface because of their greater lightness, but this is also determined by quantity; for as we have observed, each gas (according to the known conditions of equilibrium) arranges itself about a centre as if no other gas were present ; and therefore each gas must penetrate to the centre of the nebula, and therefore could not reach as far as ihe surface unless its quantity were sufficient (though, no doubt, by a greater lightness a less quantity of gas will suffice for that purpose). There might possibly be a tendency to assume (unless the conse- quences of the above principle were rigidly kept in view) that the light gas ob-erved (such as hydrogen) was floating on the surface of the nebula. We know that according to the conditions of gaseous equilibrium this is wrong, and that each gas (if freed from other disturbing causes) will have its basis at the centre of the nebula, where, therefore, the comDOsition or mixture of gaseous matter is uniform, but nowhere ele (excepting in the very improbable case where the quantities and densities of all the gaseous cocstituents are the same). If gravity were to cease (and the gaseous constituents of the nebula were supposed confined or prevented from expanding), the constituents of the nebula would uniformly diffuse themselves throughout the entire mass, and this act of diffusion would be attended by a transference of heat, even if all the gaseous constituents were at the same temperature. 6. Thus we may observe that by merely modifying the action of gravity or by altering the position of a portion of gas relatively to gravity, work may be derived through diffusion. Thus if we suppose a portion of gas to be moved to different positions in a nebula, the constitution of the portion of gas or the mixture of its constituents is changed according to its position, and in these changes work is derived, or available. Only when the portion of gas is situated at the centre of th^ nebula are its con- stituents uniformly diffused through each other ; less and less so towards the outside. 7. It would thus appear to foUow that, as far as present knowledge goes, a uniform diffusion of matter as well as a uniform diffusion of energy would be at least required, in order that all capacity for work and physical change should cease in the universe. At the same time does it not rather behove us to look to k time when, through increase of knowledge, a means for recurrence may possibly be discovered, whereby physical change is con- tinued, rather than to look to the purposeless end of a chaos of uniform temperature and uniform distribution of matter? Humboldt says relatively to this point (Preface to " Cosmos") : " I would therefore venture to hope that an attempt to delineate nature in all its vivid animation and exalted grandeur, and to trace the stable amid the vacillating ever- recurring alternation of physical meta- morphoses, will not be wholly disregarded at a future age." S. ToLVER Preston MUSIC A SCIENCE OF NUMBERS^ HTHE subject which I submit for your consideration this -*■ afternoon is the influence of numbers in music, as in the various combinations of consonances iind dissonances ' Read before the Musical Association of London, November 5, 1877, by W. ChappcU, F.S.A. Nov. 8, 1877] NATURE 33 which we hear every day, and to show how these are explained by the fundamental laws of the science. Although music has appeared to many persons a diffi- cult subject, it is really one of the most easily intelligible and one of the most firmly grounded of sciences. It is purely a science of numbers. The consonances which charm the ear, such as the octave, twelfth, fifth, fourth, and the major and minor thirds, have two concurrent sets of vibrations ; the one set produced by the lower string or pipe, and the other by the upper. Although they vibrate at different rates, yet there are periodical coincidences of vibration between them, and these coincidences sound with much more power upon the ear than the vibrations which are non- coincident, or sound apart. It has been calculated that two hammers striking simultaneously upon an anvil have, through the greater displacement of air, fourfold loudness, instead of merely double. The same law applies to musical sounds. Coincidence of vibration is more briefly expressed by its synonym, "consonance;" and all non- coincident vibrations, are included in "dissonances," meaning only that they sound apart. In a musical sense, dissonance is the medium between concord and discord, running from one into the other ; for, in the most pleasing intervals, there are some non-coincident vibrations, and when these become very numerous, they overpower all concord. This will be shown in the sequel. Suppose we take one long pianoforte string or an organ- pipe. The lowest sound it can' produce will be that of its whole length, and this may be made the foundation of an entire scale of consonant notes, for every aliquot part of the length, being such as will measure without any re- mainder, will be also a multiple of the vibrations of No. I. Thus No. 2, the octave, is half the length and vibrates twice as fast as the whole string. No. 3, the so-called twelfth, or octave and fifth, is a third of the length of No. I, and it vibrates thrice as fast. Then, if we sound No. 3 with No. 2 instead of No. i, we throw off the lower octave and have the fifth only, or 3 to 2. It is essential for consonance that the intervals should be aliquot parts of No. I, for if otherwise, we should only create discord. The musical law is expressed very simply, that the number of vibrations is in inverse ratio to the length of a string. The scale of all consonances is called the harmonic scale, copies of which are before you. It is exemplified by string or pipe. Let us consider, first, the ^olian harp, on which the winds alone produce the consecutive sounds. The strings are tuned in unison, except the two outmost, one on each side, and those are covered with wire, and tuned an octave lower. When the wind blows quickly enough to sound the bass strings, which we will suppose to have tuned to C on the bass clef, with 128 vibrations in a second of time, it is the whole string which sounds first, and the rapidity of the wind must be doubled before the harp will sound any change of note, and that note will be the octave^^above the first. It has already been said that the octave is produced by half the length of a string, and that it vibrates twice as fast as the whole — but mark the coincidence between the music and consecutive numbers ; i and 2 have no note between them, although the sound jumps from the whole length to that of the half ! When the bass strings sound the half length they have divided themselves into equal halves by a node, and that node creates tension in opposite directions, the one ventral segment pulling, as it were, against the other. These self-forming nodes may be easily seen by daylight, and at night by throwing a light upon the string. They were shown at our first conver- sazione in these rooms by Mr. Spiller, and at the Edin- burgh meeting of the British Association by Mr. Ladd. The gust of wind which sounds the octave, or half length of the bass strings of the ^olian harp, sounds at the same time the whole length of the gut strings, because they are tuned to that pitch. Then, as the wind rises, subdivision goes on in both with every multiple of 128 vibrations for the bass, and of 256 vibrations for the tenor strings. The reason for tuning the yEolian harp to a low pitch is, that the strings may be more easily acted upon by the wind. We read, poetically, of hanging one in a tree, but it requires a much stronger draught than it will get there, except during a hurricane, when no one will care to go to listen. Our late lamented Vice-President, Sir Charles Wheatstone, F.R.S., fixed a single violin string under a very draughty door, as an yEolian harp, and he calculated the increase of draught caused by lighting a fire in the room, and by the opening of an outer door, by the rising pitch of the note. The varieties produced by this string have been described as " simultaneous sounds," but they were purely consecutive. Anyone may satisfy himself that it could only be so, by repeating the experiment with a good violin string. The change of note is simultaneous with the change of nodes in the string. Mere undula- tions, or irregularities of vibration, will not change the note, but injure the quality of the tone. All the curves that a string may describe in vibration have been cal- culated by mathematicians, but only when nodes are formed are they of any importance in music. Often have I experimented upon harmonics or natural sounds, in former years, and have watched the changes of node, and have heard the simultaneous change of note. The experiments may be tried by any one who has access to a harpsichord, or a very old grand pianoforte. The tension is too great in modern instruments to allow free play to the string. Raise the damper and strike one of the longest uncovered strings with a hard pianoforte hammer near the bridge. The changes follow in nu- merical order, i, 2, 3, 4, 5, as in the paper before you, and the sounds ascend by octave, fifth, fourth, major and minor third, harmonic seventh, to the third octave, and then to the major and minor tones. It is difficult to attain the highest of these numbers, but the harmonic seventh. No. 7, is readily distinguished by its unusual sound. In the yEolian harp the rising pitch of the sounds is caused by the increasing rapidity of the wind ; but it is not so on a pianoforte. It is there due to gradual contractions of the string till it ceases to vibrate, and sinks to rest. The vibrations of a long string are widely discursive, but they become gradually more and more contracted as the nodes of the string diminish in length. The point to be remarked is that the sounds jump over intermediate discords — all are consonances — all aliquot parts : all the sounds are multiples of No. i. It matters not whether it be wind, string, or pipe ; in each of them nature teaches us the scale which is to resolve all musi- cal doubts, all disputed chords. She indicates all the basses for musical intervals, the more remote ones adapted only for melody, and the nearest for consonant harmony. To prove the case further we may take an illustration from a pipe. It must not be from those which have lateral openings, or keys, because they shorten the column of air artificially, but from such instruments as the coach horn, or hunting horn, the so-called French horn, or the trumpet without valves. The fundamental tone. No. i, or lowest sound it can produce, is derived from the whole column of air within the tube. To produce No. 2 the rapidity of the breath- ing must be doubled, and then the column of air within the horn divides itself into two equal halves, and the sound is an octave above ; so that, if the first note be tenor C with 256 vibrations in a second of time, this treble C requires to be blown at the rate of 256 vibrations to produce it. Here, again, we arrive at the identification of sounds with numbers ; for, just as there is no inter- mediate number between i and 2, so is there no inter- mediate sound between i and 2, its double in vibrations, produced by half its length, upon the horn. The 34 NATURE \Nov. 8, 1877 numbers run both ways. They are fractions as to length of tube, and multiples as to vibrations. Again, just as there ts an intermediate number between 2 and 4 (the second octave), so is there one intermediate sound, and one only ; it is No. 3, which is produced by a third of the length of the tube, and is the fifth above No. 2. The fifth and fourth divide the vibrations of the octave equally between them, so that the fifth is three times No. I, and the fourth immediately above it is four times ; — this, notwithstanding the diminution of the musical interval. The names which we have adopted for musical intervals are usually calculated from the keynote, as from C to E a third, from C to F a fourth, and from C to G a fifth, but these names are not real quantities, and are rather confusing than an assist- ance. The octave is not an eighth, but half, and the double octave is not a fifteenth, but a quarter of the length of No. i, and vibrates four times as fast. Octaves are powers of 2, thus 2, 4, 8, 16, and 32 are successive octaves. But the octave 4 to 8 has only four sounds, and these are our major and minor third, and two others, divided by the harmonic seventh, which we do not use. From 8 to 16 are eight sounds, of which we use three, the major and minor tones, and the so-called diatonic semitone, as from B to C. It is really the smallest of the eight tones, and not a semitone. The next octave is from 16 to 32, and that is all of semitones, while 32 to 64 is all of quarter-tones. After that, the octave is divided into eighths, sixteenths, and thirty- second parts of tones, among which it is only useful to note (and that only among musicians and mathemati- cians, that the so-called " comma," having the ratio of 80 to 81, is the eighth of a tone above the third of any key — as it is above E in the key of C. We have lately had mathematicians among us who are not fiovacKol, and who have, therefore, proposed to divide an octave into " twelve egna/ semitones." This is pure geometry, and not music. In music there cannot be even two equal semitones within an octave. If our friends will only change their theme from twelve equal semitones into twelve eqically tempered semitones, and give us their experience of the proposed sounds when heard with the bass (which seems not to have yet been taken into ac- count), we shall gladly avail ourselves of their research, on the grounds of modern expediency. In the meantime we must be content to leave the tempering of a scale in the hands of experienced practical men, who, judging only by their ears, as they always will, have hitherto satisfied onr immediate requirements. The interval of a fifth is 2 to 3 in ascending and 3 to 2 in descending, but, as the figures are usually placed over the upper note in scales, the 3 is written above the 2 as in the scale in your hands (the third of them), where it appears over G, referring to C as 2. And now for the practical use of these figures, for although the harmonic scale may be referred to, they are most easily remembered. All young pupils are taught the difference between an octave, a fifth, a fourth, and a third, upon the pianoforte, and it is only to associate the numbers with those intervals, to find out the best bass, and every adtnissible bass. All octaves are in the ratio of 2 to I, whether it be 4 to 2, 8 to 4, or 16 to 8. All fifths are in the ratio of 3 to 2, all fourths in that of 4 to 3, all major thirds 5 to 4, and minor thirds 6 to 5. For instance, in the key of C, C to the F above it is a fourth, and F is No. 4, therefore, the F, two octaves below, is the consonant bass ; whereas, if we strike G with the C above, C becomes the natural bass to that interval. The most consonant basses are always found in the lowest numbers, because the proportion of con- sonant vibrations is there greatest. Thus, from D to G is also a fourth, in the key of C, but the numbers are 9 to 12, with a remote bass in C, and there will be 21 vibra- tions, of which only two will coincide in every cycle — i of the 8, with i of the 9. Then, the proportion of non- coincidence will be so great as to make the sound un- pleasing to the ear. But as 9 to 12 is in the ratio of 3 to 4, we have the best bass in these lowest numbers, and take G. By the various basses to intervals we modulate into other keys. At the International Exhibition, held at South Ken- sington in 1862, Mr. Saxe, the eminent inventor of Saxe horns, exhibited an immense horn with an exceedingly long coil of tube, and perhaps standing six feet in height. When asked by the jury the object of this excesssive size and length, he answered, " Cest pour jouer dans le cinquieme ^tage " — " It is for playing in the fifth octave," and he produced with facility any of the sixteen tones and semitones of that octave from it. Half the length of any open conical tube is expended upon its second note, the octave. No human power could have blown the low notes of that horn. Supposing it to have been tuned to the lowest C upon the pianoforte, with thirty-three vibra- tions in a second, as the usual French pitch, it would have had 66, 132, 264, and 528 for its first, second, third, and fourth octaves, while its fifth octave would commence on treble C, with 528, and extend to C above the lines with 1056 vibrations in a second of time. It would thus be within the power of the lungs. He utilized only from the i6th to the 32nd part of his enormous tube, but it gave him the command of the semitones. This great incumbrance of length is not necessary in a cylindrical stopped tube. It will take up its own octave according to the ratio of its length to its diameter. We have here an example in a resonating tube invented by Charles Wheatstone just fifty years ago. The lecture for which he invented it was after- wards reported in the twenty-fifth volume of the Quarterly Jour7tal of Science, Literature, and Art, January to March, 1828. Both he and I knew Eulen- stein, an accomplished musician, whose admirable skill in playing upon the Jew's harp was the inducing cause of that particular lecture. Eulenstein had a peculiar facility for contracting and expanding the cavity of his mouth, through the pliability of his very thin cheeks and by the management of his tongue, so that he could fit them for any harmonic note within a certain compass. Wheat- stone then gave the law, that a perfect harmonic scale might be drawn from a single tuning-fork, or from the vibrating tongue of a Jew's harp, by resonators adapted, or adapting themselves, to multiples of the original number of vibrations. " I took," said Sir Charles, " a tube, closed at one end by a movable piston, and placed before its end the branch [or prong] of a vibrating tuning- fork of the ordinary pitch — C. The length of the column of air [within the tube] was six inches. On diminishing the length of the column of air to three inches [by moving up the piston], the sound of the tuning-fork was no longer reciprocated [in unison], but its octave was produced." " It is therefore evident from experiments," says he " that a column of air may vibrate by reciprocation, not only with another body whose vibrations are isochronous [or in unison] with its own, but also when the number of its own vibrations is any multiple of the sounding body." Again, he says : " No other sounds can be produced by reciprocation from a column of air, but those which are perfectly identical with the multiplications of the original vibrations of the tuning-fork or the tongue of the Jew's harp." I produced the original tube in this room about two years ago, to check a recent theory — that reso- nators strengthened the ear, and answered only in unison, and Sir Charles ordered this one for me, made by Mr. Groves, under his own superintendence. The improvement in this is, that the piston now works in a groove and is not liable to stick. Two octaves are pro- duced from the tongue of one Jew's harp as rapidly as the piston can be moved up and down. There is AW. 8, 1877] NATURE 35 no slurring between one sound and another, but clear jumps from one multiple to another, and every one of them may be arrested and heard by itself by checking the piston. But, although I am glad to produce this tube before those who were not present on the last occasion, and to do honour to the memory of our eminent vice- president, who declined to refer in any way to himself, I have another motive also. This is a principle which has never been utilised. We have had pipes stopped at the top, like the usual pitch-pipe, but they have been found too slow in action to be suitable for any other purpose. This is rapidity itself, and might surely be utilised for some such purpose as pedal-pipes for an organ. The piston can be balanced outside to the greatest nicety, and one such pipe will take the scale of C, and another that of F. All that is required is to blow across the top in the manner of the Pandean pipes, or, as it appears, better still, to set free a fan or cogged wheel at the mouth tuned to each of the two fundamental notes. The wheel might be set free by the action of the foot upon the pedal. It is now well known that the length of a 32 or a 16 foot pipe may be greatly reduced by breadth of scale. We Europeans have made little, if any, use of resonators, and yet they have been long in use in Java. The drawing on the wall is of an instrument brought from Java by Sir Stamford Raffles more than half a century ago. There is one of the same kind in the British Museum. But this is perhaps of greater interest, as it may have suggested to Wheatstone the prin- ciple of the resonating tube. The natives of Java cast metal plates which they suspend in a row upon strings, and strike them with drum-sticks, which are fitted into circular heads. As all cast metal is more or less false in tone, owing to inequalities and lack of homogeneity, they place some of the largest bamboos, cut to short lengths, and placed upright, under the metal to make the true sounds of these resonators to overcome the false har- monics of the metal plates. Resonators were used in the theatres of ancient Greece • — we here find them used in Java ; but these powerful auxiliaries to tone still await their development in modern Europe. And now, in conclusion, permit me to draw your atten- to a harmonium with two keyboards, the upper one having four octaves of our scale tuned without tempering, and the lower with the five octaves of the harmonic scale, and the sixteen notes in the fifth octave. Much has been said of the harmonic scale, and this is perhaps the only instrument on which the harmonics can be fully heard and sustained for experimental use. ROBERT SWINHOE, F,R.S. V\riTHIN the last thirty years or so their respective * * vocations happen to have called two able lovers of natural history in the direction of the Celestial Empire — Mr. Robert Swinhoe, from England, and the P^re Armand David, a Frenchman. The simultaneous inves- tigations of these two biologists have added immensely to our knowledge of a country whose fauna not long ago was thought to be in no way interesting, because the huge population had succeeded in extirpating all the indige- nous species. How far from the truth such an assumption is, has been demonstrated by the researches of the two naturalists above mentioned, the lamented death of the former of whom, at the early age of forty-one years, we recorded last week. Mr. Swinhoe was born at Calcutta on September i, 1836, and was educated at King's College, London, whence he matriculated at the University of London, in 1853. The next year he went, as supernumerary inter- preter, to Hong Kong, being transferred to Amoy in 1855, and to Shanghai in 1858. In the same year he was attached to the Earl of Elgin's special mission to China, and afterwards to H.M.S. Inflexible as interpreter in a circumnavigating expedition round Formosa, in search of certain Europeans said to have been held in captivity at the sulphur mines on the island. In i860 Mr, Swinhoe attended Gen. Napier, and after- wards Sir Hope Grant, the Commander-in-Chief, as inter- preter, and received a medal for war service. At the end of the same year he was appointed Vice-Consul at Taiwan, Formosa, and in 1865 to the full Consulship. In 1866 he was Consul, temporarily, at Amoy, and in 1868 went to explore the Island of Hainan. From May, 1871, to February, 1873, he was acting Consul at Ningpo, and at Chefoo until October of the latter year, when he had to retire from the service, on account of increasing para- plegia, from which he died on October 28 last. Mr. Swmhoe was a Fellow of the Asiatic Societies of China and of Bengal, as well as of many other societies, having been elected into the Royal Society in 1876. By far the majority of Mr. Swinhoe's scientific com- munications— fifty-two in number — mostly on the mam- malia and birds of China, are to be found in the Proceedings of the Zoological Society of London between 1861 and 1874, Other papers appeared in the Ibis and the Annals and Magazine of Natural History within the same period. Among the most important of these are the I' Catalogues " of the mammals and birds of China and its islands, in which are to be found descriptions of many new species of both classes, among which are St. John's Macaque {Macaciis sancii-johaimis), the Water Deer of Shanghai {Hydropotes incrnris), the Mantchurian Deer {Cerviis mantchnriciis), the Orange-bellied Helictis \H elicits subaurantiaca), the Superb Flying Squirrel [Pteromys grandis), Boyce's Stork .Ciconia boyciana), together with a great number of other birds, for a com- plete account of which we cannot do better than refer our readers to a work upon the birds of China, by M. I'Abbd David and M. E. Oustalet, published at Paris a week ago. Michie's Deer {^Lophotra^ris michianus) is the name given by Mr. Swinhoe to a small deer from Ningpo, with antlers more diminutive than many other species. This, or a very closely-allied species, was previously sent to Paris by Pere David, and described by M. A. Milne- Edwards under the name Elaphodus cephalophus. Mr. Swinhoe, besides the coUecnons which he made, was indefatigable and particularly successful in his endeavours to send living animals from China to this country, and there are many species, including Cervus s7vinhoiiy Hydropotes incrnris, and Ciconia boyciana, which were first procured by him. It will be some time, we fear, before so enterprising a naturalist as Mr. Swinhoe takes up his residence in China, and employs every available opportunity for the prosecution of his favourite line of research. DOUGLAS A. SPALDING OUR readers 'must be familiar with this name as that of an occasional contributor to Nature of thought- ful and acute articles in the department of mental science ; they will be sorry to hear— but those who knew him will not be surprised — that Mr. Spalding died on October 31, at Dunkirk, just as he was preparing to go to the Mediterranean coast to spend the winter. Not much is known of Mr. Spalding's early life, but we are told by one who ought to know that his parents, belonging to Aberdeenshire, were in very humble circumstances, and that he was born in London about the year 1840. He himself spent his early years in Aberdeen as a working slater, doing his best to educate himself. By the kind- ness of Prof. Bain Mr. Spalding was allowed to attend the classes of Literature and Philosophy in Aberdeen University free of charge, in the year 1862. After that he got some teaching about London, and worked very hard to support himself, and even managed to keep his 36 NATURE \Nov. 8, 1877 terms as barrister, though he never practised. It was during this period of privation that he contracted disease of the lungs, from which he suffered greatly up to the time of his premature death. The first thing that brought him to the notice of the scientific world was his experiments on the instinctive movements of birds, which were first described at the Brighton meeting of the British Association in 1872, and published va. Mac7nillan's Maoa- zine for February, 1873. From a series of interesting experiments on chickens he showed that the only theory in explanation of the phenomena of instinct that has an air of science about it is the doctrine of inherited associa- tion. Instinct, he maintained, in the present generation of animals, is the product of the accumulated experiences of past generations. In another paper at the Bristol meeting of 1875 he communicated the results of further experiments, some described in Nature, vol. viii. p. 289, bearing out still more strongly the conclusions he had already reached, and which he summed up in the statement that " animals and men are conscious automata." The Brighton paper brought Mr. Spalding into deserved repute. "While travelling in France he became acquainted with John Stuart Mill, and through him afterwards with many other distinguished men, who all treated Spalding with great respect. Through Mill also, we believe, he became acquainted with Lord and Lady Amberley, with whom he lived as companion and tutor to their children from 1873 until the death of Lord Amberley. Mr. Spalding was appointed guardian to the children, but was ultimately compelled to withdraw from this office owing to his religious opinions, Earl Russell, however, allowing him to retain for life the salary settled upon him by Lord Amberley. For the last two years Mr, Spalding has lived mostly in the south of France, bearing his fatal and pro- tracting illness with the greatest equanimity, regretting only his po verlessness to work and his enforced absence from London. As to the value of his scientific work our readers having the material before them are able to judge. By his experi- ments on animals he didmuch not only to clearup the nature of what is call .d instinct, but also to shed a new light on certain mental phenomena in man himself. His papers in Nature, mo ,tly reviews of works connected with psycho- logy, on the metaphysics of instinct and evolution— of the latter doctrine he was a warm advocate — were good speci- mens of clear and close reasoning. That he had a tender side to his character is evident from even his Association papers, and still more so from the interesting letters written by him to Nature, last April, on the swallows and cuckoos at Menton. All who knew him felt that had his health permitted he would have added largely to scientific knowledge in the special department to which he had devoted himself— physiological psychology. OUR ASTRONOMICAL COLUMN The Solar Eclipse of 1878, February 2.— The eclipse of the sun in February next will be annular, but the central line passes at such high southern latitudes that the annular phase is not likely to be observed unless it be in the western parts of Tasmania near sun-set. Thus the central eclipse will commence in longitude 103° o' west of Greenwich, latitude 73° 8' south, and will end in longi- tude 149° 25' east, latitude 40° 58', and the eclipse is cen- tral at noon m longitude 112° 27' west, and latitude 84° 3' south. Another point upon the central line is in longitude 145 25 east, and latitude 42° 25', where the sun's altitude however, will be less than 4° ; this point lies on the west coast of Tasmania. Launceston is near the central line but at the midule of the eclipse the sun at that place is almost in the horizon. A large partial eclipse will be visible over the southern parts of Australia. At Melbourne it will commence at Oh. im. P.M. local mean time, at 120° from the sun's north point towards the west, and will attain its greatest magni- tude o"9i, just before sunset, or at 7h. 4. At Adelaide the eclipse will begin at 5h. 44m. local time and will be greatest about 6h. 45m., when the magnitude will be 085, with the sun at an altitude of between f" and 6°. At Perth, in Western Australia, the whole eclipse will be visible ; greatest about 5h. 25m. local time, magnitude o"66, with the sun at an elevation of 23°. The next total eclipse of the sun visible in those parts of the earth will take place on the morning of September 9, 1885. At Wellington, New Zealand, the ecUpse begins about a quarter of an hour after sunrise ; totality com- mences at 7h. 42m. A.M., but continues only about forty seconds ; in 175° 3' east, and 40° 34' south, on the central line, the duration of totality is im. 54s. It should be stated that these figures are founded upon the tables of Damoiseau and Carlini. The Minor Planet Euphrosyne. — It does not frequently happen that we have to look for a planet at 60° of north declination ; such, however, will be the case at the end of the present year, and in the first days of 1878 as regards Euphrosyne, No. 31 of the group, which was discovered by Ferguson at Washington, on September i, 1854. The planet will be in opposition on December 18, with the brightness of a star of the tenth magnitude. The following are its calculated positions when passing its greatest northern declination. Distance i2h. Berlin M.T. Right Asceasion. Declioatlon. from the h. m. s. o , ,; Earth. 1877, December 31 ... 52017-1 ... 60256 ... I'6i3 1878, January i ... 51849-5 ... 60259 ... 1-614 ,, ,, 2 ... 51724-1 ... 60238 ... 1-618 The star L. 10067 ij^ Camelopardus, which Lalande calls an eighth, and Argelander a seventh, will be a good guide for identifying the planet in this position. At midnight at Greenwich on January i, by calculation, Euphrosyne will precede the star seven seconds in R.A., seven minutes to the south of it. The latest elements of this body which, it will be seen, approaches much nearer to the pole of the equator than the generality of the small planets, are as follows, according to the computations of Mr. S. W. Hill : — Epoch 1877, December 18 o M.T. at Berlin. Mean Longitude ... ... ... ... 901023 Longitude of Perihelion ... ... ... 93 17 30 ,, Ascending Node ... ... 313323 Inclination ... ... ... ... ... 26 28 34 Eccentricity ... ... ... ... ... 0-222786 Semi-axis major ... ... ... ... ... 3-14902 Comets of Short Period in 1878.— Of the comets known to be performing their revolutions in periods of less than ten years, two are due in perihelion again in the ensuing year, probably within a few days of each other. According to Dr. von Asten's elements of Encke's comet at its appearance in 1875, the next perihelion passage, neglecting perturbation, would fall about July 27-0, which involves an apparent track in the heavens un- favourable for observation. In 1845, when the con- ditions were more nearly the same than at any of the comet's returns since its periodicity was first ascertained, only four observations were secured between July 4 and 14 — at Rome, Philadelphia, and Washington. If the comet is not observed [before the perihelion in 1878, while at a considerable distance from the earth, it may be found at the observatories of the southern hemisphere, after perihelion, or in the latter part of August, when it makes its nearest approach to us, although its distance at that time will not be less than the mean distance of the earth from the sun. The second comet, which is due in perihelion in 1878, is that discovered by Dr. Tempel on July I, 1873, The period of revolution assigned by Mr. W. E. Plummer from observations extending to October 20, is 1,850 days ; and the comet, neglecting perturbations Nov, 8, 1877] NATURE 37 which are not likely to be material, would be in perihelion again about July 20 ; this date, however, will be uncer- tain, as thus far no definite discussion of the observations in 1873 has been published. Some time since it was stated that Herr Schulhof, of the Vienna Observatory, was at work upon this comet. With the above date for perihelion passage, the apparent path would be favourable for observations, and the comet would approach the earth almost as closely as is possible with the actual form of orbit. NOTES The session of the Royal Society opens next Thursday with the Bakerian Lecture On the Organisation of the Fossil Plants of the Coal Measures, Part ix., which will be delivered by Prof. W. C. Williamson, of Manchester, F. R.S. We learn from the Titnes that the following is the list of the new Council which will be submitted to the Royal Society for election at their anniversary meeting on St. Andrew's Day next, the 30th instant : — President, Sir Joseph Dalton Hooker, C.B., K.C.S.I., M.D., D.C.L., LL.D. ; Treasurer, William Spottiswoode, M.A., LL.D. ; Secretaries, Prof. George Gabriel Stokes, M.A. D.C.L., LL.D., Prof. Thomas Henry Huxley, LL D. ; Foreign Secretary, Prof. Alexander William Williamson, Ph.D. ; other members of the Council— Frederick A. Abel, C.B., V.P.C.S., William Bow- man, F.R.C.S., Frederick J. Bramwell, M.I.C.E., William B. Carpenter, C.B., M.D., LL.D., William Carruthers, F.L.S., William Crookes, V.P.C.S., Prof. P. Martin Duncan, M.B., P.G.S., William Farr, M.D., D.C.L., Prof. William H. Flower, F.R.C.S., Prof. G. Carey Foster, B.A., F.C.S., John Russell Hind, F.R.A.S., Lord Rayleigh, M.A., Vice-Admiral Sir G. H. Richards, C.B., Prof. Henry J. Stephen Smith, M.A., Prof. Balfour Stewart, M.A., and Pro^. Allen Thomson, M.D., F.R.S.E. Mr. F. M. Balfour, Fellow and Lecturer of Trinity College, Cambridge, has joined the editorial staff of the Quarterly Journal of Microscopic Science. The journal will in future be conducted by Prof. Ray Lankester as responsible editor, with the co-opera- tion of Mr. Archer in Dublin, Mr. Balfour in Cambridge, and Dr. Klein in London. The volume for the year just concluded shows an increase in the number and efficiency of the lithographic plates. Instead of sixteen octavo plates as usual four years ago, there are twenty-five, many of which are double sized, and some coloured. Madame Leverrier, the' widow of the astronomer, died on November i, at the age of fifty-eight years. This lady was suffering from a protracted illness, when the loss of her husband produced a shock from which she was not able to recover. She was a daughter of M. Choquet, an eminent professor of mathe- matics in Paris. Her father, about e'ghty years old, was present at the funeral. On the very day that Madame Leverrier died, the yournal Officiel published a decree, signed by M. Brunet, the Minister of Public Instruction, ordering the bust of Leverrier to be placed in the Palace at Versailles, where are to be collected the memorials of the great Frenchmen of the nineteenth century. This honour has been decreed to a number of other men who have ranked foremost amongst litterateurs, artists, or politicians. M. Leverrier, it is strange to say, has been chosen as the only representative of science. The French Academy of Medicine has been authorised by the ministry to accept a legacy of 4,000/. bequeathed by Dr. Demor- quay, to help them to build a hall of meeting. M. Faye, Inspector-General in Science of Secondary Edu- cation in France, has been appointed to a similar office for superior education in buccession to the late M. Leverrier. M. Fernet has succeeded to M. Faye's post. M. Watteville, director of Arts and Sciences in the French Ministry of Pubhc Instruction, has issued a circular notifying that a special exhibition will be held at the Champ de Mars, for collecting the results of the scientific missions granted by the French Government in 1867. Almost every country, civilised and barbarian, near or remote, has been visited. M. Bertrand, the perpetual secretary of the French Academy of Sciences, has been appointed by M. Bonnet member of the International Metric Commission. Commander Guiseppe Telfener has announced his inten- tion of placing at the disposal of the Italian Geographical Society a sum of 40,000 francs to found a section of commercial geography and organise at Rome a museum to contain specimens of all the products which Italy exports and imports. At a meeting held at the London Library on October 26 (Mr. Robert Harrison in the chair), it was determined to form an Index Society, with the immediate object of compiling subject indexes and indexes of standard books of facts, to be printed and circulated among the members ; and with the ultimate object of building up a general index of universal literature, which can be referred to at the office of the society during com- pilation. The great aim of the society will be the gradual accumulation of aids towards the preparation of a key to all knowledge, and with this object a library of indexes will be commenced. The subscription will be one guinea. Subscribers' names and suggestions on the subject of the proposed society will be received by Henry B. Wheatley, hon. sec. pro tern., 5, Minford Gardens, West Kensington Park, W. The utility of such a society and such an index to scientific men of all classes and grades will be obvious, and the effort now being made deserves their hearty support. The system under which the official addresses are made at the annual meeting of the American Association for the Advance- ment of Science seems curiously complicated, and sometimes is a puzzle even to the old members of that body. The retiring president, who has been the presiding officer in the preceding year, makes the opening address, which is the presidential address for that year. The presidents of the sections, on the other hand, who have just entered on their duties, open their sections respectively with an address. There are only two sec- tions, A and B ; other divisions are parts of these, and are characterised as sub-sections. Section A has charge of mathe- matics, astronomy, physics, chemistry, and microscopy ; Section B of zoology, botany, geology, palaeontology, ethnology, and archaeology. There is a further complication in the circumstance that the presidents of the sections are also the two vice-presidents of the Association. To illustrate this arrangement, we may cite proceedings at the meeting of last August at Nashville. Prof. W. B. Rogers, who was the president of the Association last year, and president at the Buffalo meeting, was expected to open the Nashville meeting with the presidential address, but was prevented by illneis. Professors E. C. Pickering and O. C. Marsh are respectively presidents for the present year of Sections A and B, and also vice-presidents of the Association. The address on "The Introduction and Succession of Vertebrate Life in America," by Prof. Marsh, which we recently published in full, was his official address as the president of Section B, delivered at the opening of the Section. To carry the illustra- tion further, it may be added that Prof. Marsh, who was elected at this year's meeting, president of the Association, will not preside till next year at St. Louis, and will not be expected to deliver his presidential address unul the meeting of the following year, 1879. The death is announced of Dr. Henry Lawson, until recentiy editor of the Popular Science Review. Mr. James Flower, for many years the articulator of the skeletons at the Royal College of Surgeons, has just died from 38 NATURE \lo mbouve anatomised by Duvernay, is delineated in four attitudes, and the reach of the fingers below the knee is well shown ; below it are three capital chimpanzees, but none of them equalling Wolf's admirable swinging chimpanzee in the possession of the Zoological Society of London, The orangs with their globular heads, projecting lips, and hirsute arms, are drawn with great force, and three gibbons, spidery and dangling, complete the show. A plate of hands and feet illustrates this part of the book, and the transition from the highest hand, probably that of T. tschiego, for it is more symmetrical than that of gorilla, to the lowest paw amongst the American mar- mosets is admirably shown. The dwindling of the thumb, the gradual equalisation in length of the three middle fingers, and the march first on the knuckles, and then, in the lower groups, on the palms are carefully demon- strated. Osteological anatomy is not much cared for, and therefore the skeleton of gorilla is not worthy of the book ; but in the chapter on this great ape there are some very remarkable plates which enable us to approach the truth. The chimpanzee comes next — and oh ! there is such a sly-faced fellow in a woodcut, utterly beyond the capacity of anyBritishcutter on wood— illustrating the genial species, after which, instead of before, as one would think ought to have been done, comes Du Chaillu's bald Troglodyte, the T. tschiego. With regard to this little-known beast, Vou XVII. — No, 420 Brehm gives some more information about its size and general zoology, but he does not enlarge on the Troglo- dytes aubryi of Gratiolet and Alix. A group of Entellus monkeys, with their forehead tufts rather exaggerated, illustrates in part the few pages on the Semnopitheci, and the Macaci are finely delineated, a life-like savagery being given to the Rhesus and pig-tailed kinds, Brehm's anec- dotes about the baboons are first-rate, and although the drawings of Hamadryas and the mandrill are slightly in exaggeration of what is common, they give a capital idea of the impudence of the one and the brutality of the other, Brehm has collected all the good anecdotes and descrip- tions from Humboldt, Schomburgk, Rennger, and Henfel about the Howlers, and in spite of the silence of those in captivity in Europe we can imagine the terrific noise of a tree full of the adults oi Mycetes car ay a. Bartlett is fully and deservedly quoted in illustration of the natural history of the spider monkeys, and the delineations of the group are fairly done, ease of position being often wanting in the illustrations, however. The short-tailed Brachyures are for once described and drawn not in caricature ; the context is mainly from Bates, and the sketch looks like a monkey and not like the distressed old man with a tail like an American vegetable marrow which is usually given in books. The Saimaris are introduced under the generic title Pithesciurus to which, and indeed to much 0£ Brehm's zoological nomenclature, we demur. The mar. mosets are grouped, as by Huxley, as Arctopitheci, a name given to some sloths by Gray, and there is much con- fusion in introducing new generic terms to the genera Hapale and Midas. The use of the term Leopithecus for Hapale, of- Hapale for Midas, for instance, shows the necessity for a final zoological arrangement of these small monkeys. No less than 239 pages are devoted to the apes and monkeys, and then the Lemuroida are com- menced under the old-fashioned terms Hemipitheci or Prosimii. Sonnerat, Pollen, and Peters are Brehm's authorities for the natural history of this group, and he does not appear to have had the advantage of studying Mivart, Murie, Grandidier, and Owen ; nevertheless the article is of good scientific value and of course the illus- trations are superexcellent. There is, however, the old jumble of synonyms for the genus Indris, and Lichanotus and Propithecus are put in most unadvisedly. The queer Stenops, oddly named gracilis, Galago with his ears on the move and a bogie of Tarsitts spectrum — if it were as big as a man how truly hobgoblin-like it would be — are excellent pictures. There is nothing new, however, about the group, and really more good information on anatomical and physiological subjects might have been given without detracting from the popular nature of the book. The Chiroptera are arranged in rather an old-fashioned manner, and are rather curtly treated ; and then the second part of the volume opens with the Carnivora, to the exclusion of the Insectivora. The lion of course comes first, and although there is nothing to notice particularly in the context, every one must admire Leo capensis and the lioness of Leo senegaletisis, although the specific determinations should sink into those of varieties. The sequence of species then becomes rather strange to English natural history, the puma and Felis eyra pre- ceding " Tigris regalis " or Felis tigris. The clouded P 42 NATURE \Nov. 15, 1877 tiger comes next as " Neofelis," and the illustration is hardly that of the short-legged meek- looking creature in the Zoological Gardens. The jaguar, as drawn in the next page is too long in the neck, but the rounded top to the head is well given ; the anecdotes and general history of this fine South American beast are beyond ordinary praise. Brehm has paid unusual attention to the smaller cats, and the pages devoted to them are amongst the most interesting in the book, and when telling of the lynx, he gives a wood engraving by Beckmann of the common form which is wonderful in its details of face- expression and fur (p. 490). The Cheetahs, so interestingly numerous just now in our Zoological Gardens, are fully considered, and in the illustration there is the upward whisk of the tail given to perfection, but the muzzle of the beast is too long, and the fore legs hardly long and stilty enough. Cryptoprocta concludes the Felidse, and Cams primczviis of Cashmir commences a most interesting article on the dogs. Amongst other beauties there is " Der BuUdogg oder Boxer," and Mr. Bill Sykes would have been surprised to have learnt that it is .called Catiis familiaris molossus gladiator. It is "ein wiithendes, unzugangliches und stumpfsinniges Thier." Then there is its relation, Mops, with its sharply curled-up tail and black short nose, the tiny tongue tip not, however, being shown in the engrav- ing, which tells the ladies of the period that Pug's real name is Canis familiaris molossus fricator. Amongst other dogs a sketch of a pointer by Beckmann is capital ; he is pointing, and just a little in doubt, the tail dropping slightly and the head being not over-expectant. The first volume concludes with the natural history of Otocyon and Canis procyonides. The second volume commences with a notice of the hyaenas, and although there is not much to be said in praise of this contribution to their literature, still the delineations of H. crocuta and H. briinnea place the dis- tinctions between the species plainly. H. crocuta is admirably drawn and the artist has managed to give it the peculiar weak look of the hind legs and drooping quarters of the caged animal. The Viverridse are shortly treated, and one of the few doubtful drawings of the work is in illustration of Cynogale bennettii. The genus Herpestes, the habits of some of whose species have taxed the imagination of Europeans as well as that of Eastern races, follows ; it is judiciously described and the anecdotes are good. The fur-yielding martens and their allies and other small carnivora valuable to the furrier are well illustrated, but Brehm had not the valuable volume on their natural history, lately issued by the American Survey, to learn from. The bears form a very interesting part of the book, but many of the illustrations have the positions of the animals rendered awkward by the attempt to give prominence to specific and peculiar structural points. Thus the polar bear in the water is wretchedly done, thanks to the endeavour to render the claws and narrowish snout very definitely comprehensible. The moles and hedgehogs are fairly noticed, but want of space begins to affect the treatment of these lower groups, but Galeopithecus, very shortly described, is properly placed at the head of the Insectivora. The Rodentia are of course full of anecdote and light literature, but Brehm's illustrations are by no means as good as those of the other groups ; perhaps the most striking is that of Cercolabes prehensilis, A capital plate of the sloth shows the short snout which almost looks moist, and for once in a way amongst books of this kind, there is a truthful rendering of the long narrow wrist with its two claws. The essay on the sloths and ant-eaters is admirable, but the anxiety to show the ipeculiar progression of the last group, on the anterior extremities and the position of the claws, has often led the artist to exaggerate. The Mar- supials are well illustrated and with great ability, but we miss some of Gould's most life-like sketches so familiar in most popular works. The pages devoted to the Mono- tremes contain the usual stories, and unfortunately were written before those important additions to their natural history were published, and which have lately been noticed in Nature. The other volume (the ninth of the work) before us is by Taschenberg, of Halle, and is a second edition of the part containing the Insecta, Myriopoda, and Arachnida. The species representing groups are of course well chosen as types, and the author has often taken pains to place novel- ties before the reader, especially in the way of illustration. The short anatomical introduction is sufficient for the general reader, but barely so for the young student. Amongst unusual forms, or rather unusual to the common routine of book making, is Mormolyce phyllodes, from the upper hill country of Java, with its wide leaf-looking elytra and long antennse, and the very common and opposite- looking Scarites pyracmon. The burying propensities of Necrophorus are told and illustrated, and there is a very curious and striking plate of a mole hanging by the neck in a trap, with a crowd of Silphidas (shield beetles) and larvae, besides blow-flies, on and about it, doing their best to turn its protoplasm into theirs. Some pests to museum-keepers and housekeepers are especially figured in the act of working away at a hare's foot which rests on pen, ink, and paper Anthrenus muscermn larva and adult, Attagenus pellio and Dermestes lardarius are there in full enjoyment of their mischievous propensities. The natural history of Lampyris, Meloe, and Sitaris, is cut too short, doubtless for want of space, but their interest- ing life cycles merit more attention than that of many others which are barely more than mentioned by name and might be left out. Apoderus longicollis, a Javanese species looking like a cameleopard amongst beetles, and unfortunately little known, has an interesting engraving ; and equally good is that of the langkafer Brenthus. Amongst the Hymenoptera the habits and nests of Bombus terrestris, of Odynerus parietum, and of the curious Belonogaster and the Sandwasp are very well explained and drawn ; and great praise must be given to the delineations of the life cycle of Othalia and Cimbex. The only fault to be found in the treatment of the Lepidoptera is that the article is too short, but the illus- trations are very good. A plate of a rush of a myriad of the maggots of Sciai-a militaris is a strange subject, but very effective, and the long crowd of closely-packed dark- headed long things looks as if short work was to be made of carrion. Amongst the leaf insects there is Mantis religiosa preying rather than praying with a fly in its clasp, and a host of larvae escaping from a mass of eggs ; and there is an equally interesting cut of Bacillus Rossii, one of the Phasmodea. A short chapter on the unsavoury subject of Pediculi precedes a sketch of the Cochineal Nov. 15, I $7 7] NATURE 43 insects, and then, after'noticing the Chermes that attacks that very strong food the larch, we come to a full descrip- tion of Phylloxera vastatrix. The Hemiptera are shortly mentioned, and then the Myriopoda. There is a good picture of Geophilus clinging around its great prey, a large earthworm, and also of a Polydesmus. Amongst the Scorpions the long-armed Phrynus and Gonoleptes, and amongst the Spiders a long Tetragnatha and the extraordinary-bellied Gasteracantha, form admirable illus- trations. A short chapter on Pycnogonum and Nymphon concludes this really wonderful volume. P. M. D. OUR BOOK SHELF Heat. By B. Loewy (Lardner's Handbook of Natural Philosophy. Crosby Lockwood and Co., 1877.) This, though not a bulky book, is a sort of miniature Encyclopeedia of the subject. So far as we have read it it seems to have all the faults of the original (?) work to which Lardner's name was prefixed, with the important exception of the inaccuracies. These have been to a great extent removed, and the work has been brought up to date, but there is still the woeful want of order, or indeed of any guiding principle whatever which distin- guished the former editions. It is a very curious mixture of good and bad, and cannot be called, in any sense, attractive to the reader. Numerous tables of expe- rimental data are given, but they are in many cases carried to a number of places of figures quite beyond the present power of experimental science. Two, or perhaps three of tbe figures in the earlier places of each number are probably correct ; the others give a show of minute accuracy which may altogether deceive the beginner. The treatment of the theoretical part is very meagre, but in the experimental part many curious facts not usually known are given. The book may be useful as a work of reference to those who are not in possession of Balfour Stewart's treatise, but we cannot say more in its favour. Ferns, British and Foreign. The History, Organography, Classificatioti, a7id Enumeration of the Species 0/ Garden Fertts, with a Treatise on their Cultivation. By John Smith, A.L.S., Ex-Curator of the Royal Gardens, Kew. New and Enlarged Edition. (London : Hardwicke and Bogue, 1877.) That Mr. Smith's " Ferns, British and Foreign " should have reached a new edition in a comparatively short time is no small tribute to its value as a book of reference for amateurs and fern cultivators. The chief portion of this very neatly got up work is occupied by an enumera- tion of cultivated ferns. The different genera, as under- stood by the author, who was one of the foremost pteri- dologistsjof his day, are described and figured, while a list of the cultivated forms, with synonyms and range of geographical distribution, follow under each genus, no attempt being made to give a diagnosis of the species. The scope of the work is therefore entirely different from that of the " Synopsis Fihcum " of Hooker and Baker. The classification adopted is that propounded by Mr. Smith in his early publication on ferns, an arrangement not much used by modem writers. An appendix of recently-introduced ferns is given. These have been col- lected and arranged under their respective genera and tribes, as their names have from time to time been noticed in the horticultural journals and in nurserymen's catalogues. The list has thus no pretensions to be a critical one. The most interesting part of the book is the history of the, introduction of exotic ferns, a subject about which, probably, no man living knows more than Mr. Smith. This is followed by an explanation of terms used in describing ferns, perhaps the least satisfactory part of the whole volume, as many of the terms are more or less obsolete, or only used in the book now before us. In this section nothing is said about the recent researches into the nature of the prothallus, construction of the reproduc- tive organs, and morphological nature of the sporangia. The last part of the work is occupied by an essay on the cultivation of ferns, reprinted without alteration from the first edition, but giving the results of long expeiience of the successful cultivation of all groups of ferns. As a work of reference and guide to the cultivation, this book will most undoubtedly be of great service to the fern- growing public. LETTERS TO THE EDITOR [The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undetiake to return, or to correspond with the writers of, rejected manuscripts. No notice is taken of anonymous communications. The Editor urgently requests correspondents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of com- munications containing interesting and novel facts.l The Radiometer and its Lessons I HAVE little doubt that Prof. Osborne Reynolds is much more competent than I am to say what is or is not consistent with the kinetic theory of gases, but I hardly think that he gives evidence of this in his letter to last week's Nature (p. 27). Unless my Ignorance of the matter is more complete than I am aware of, the law that the rate of communication of heat to a gas is inde- pendent of the density, applies only when the space occupied by the gas is so great, or the variations of density so small, that these variations do not alter the temperatures of those portions of the gas which are at each instant respectively re- ceiving and giving out heat. This condition cannot, I imagine, be fulfilled in the radiometer, where it seems to me inevitable that an action of the kind to which Mr. Johnstone Stoney called attention must take place. G. Carey Foster P.S. — Since writing my previous letter to Nature, a fort- night ago, I have read a paper by Mr. R. Finkener, in Foggen- dorff^'s Annalen (vol. clviii. pp. S72-595). This paper contains, besides a theoretical investigation of the motion of the radio- meter founded oft the kinetic theory of gases, an experimental proof that the action becomes much less when an extremely high degree of rarefaction is reached. The paper itself is not dated, but, as the Part of the Annalen which contains it was " closed " on July 31, 1876, the experiments described in it cannot have been much, if at all, subsequent to those (communicated to the Rojal Society, June 13, 1876) which led Mr. Crookes to a like result. G. C. F. Until I read Dr. Carpenter's letter in your issue of the 8th inst., it had never occurred to me that his "special purpose" was to bring out strongly my " thoroughly scientific and philo- sophical method ! " This is an act of disinterested kindness which recalls to me the exquisite truth ot Dean Swift's remark, " No enemy can match a friend.' Dr. Carpenter's only reply to my letter which appeared in your issue of the ist inst. is contained in the following passage : — "If I had not found," he says, "after the publication of my Lectures, that he had himself been 'digging up the hatchet,' which I was quite disposed to keep buried, by giving his public attestation to the ' spiritualistic ' genuineness of what had been proved to be a most barefaced imposture, I should not have again brought his name into the controversy." Further on Dr. Carpenter paraphrases passages from his article in Eraser's Magazine for this month, in which he goes more into detail touching this "public attestation," of which in his eyes I " Eva Fay," he says, "returned to the United States, carrying with her a letter from Mr. Crookes, which set forth that since doubts had been thrown on the Spiritualistic natvu'e of her ' manifestations,' and since he in common with other Fellows of the Royal Society had satisfied himself of their genuineness by ' scientific tests,' he willingly gave her the benefit of his attesta- tion. This letter was pubUshed in facsimile in American newspapers." My answer to this calumny shall be brief. It is untrue that I dug up the hatcbet—Dr. Carpenters 44 NATURE [Nov. 15, 1877 expression — in the interval between November 30, 1875, when he proposed it should be buried, and the time of his first subsequent attack upon me. It is untrue that during this interval, or at any other time, I gave my "public attestation to the spiritualistic genuineness of what had been proved to be a most barefaced imposture." It is untrue that I gave Eva Fay a letter, speaking of the "Spiritualistic nature of her manifestations," and referring to " Fellows of the Royal Society." It is untrue that Eva Fay "returned to the United States carrying with her " such a letter. It is untrue that "this letter was published va. facsimih in American newspapers." When Dr. Carpenter limits himself to definite statements, my task is not difficult. It is, however, less easy to answer a ruinour of something which somebody told Dr. Carpenter I privately admitted. "It has been rumoured," says Dr. Carpenter, in Eraser's Magazine, "that Mr. Crookes has privately admitted that some of his 'mediums,' when they could not evoke the 'manifesta- tions ' by fair means, have done so hy foul." I admit that such a rumour respecting Eva Fay was circulated in the United States, and a Boston gentleman wrote and asked me if there was any truth in this statement. I replied as follows under date Novembers, 1875 : — " In reply to your favour of October 25, which I have received this morning, I beg to state that no one has any authority from me to state that I have any doubts of Mrs. Fay's mediumship. The published accounts of the test seances which took place at my house are the best evidence which I can give of my belief in Mrs. Fay's powers. I should be sorry to find that any such rumours as you mention should injure Mrs. Fay, whom I always found most ready to submit to any conditions I thought fit to propose." Considering that this was a private letter from one gentleman to another, written currente calamo without any thought of sub- sequent publication, few of your readers, I believe, will see much harm in it. Not being aware that private communications were less sacred in America than in England, I was certainly surprised one moaning to receive a copy of an American news- paper containing a facsimile of this private letter. It will be observed that this letter is dated November 8, 1875, whereas the " bury-the-hatchet " episode took place on Novem- ber 30, 1875 ; this therefore cannot be the letttSr which convicts me of attesting to a " barefaced imposture " subsequent to November 30. Moreover, this letter does not contain the words " Spiritual- istic nature of her manifestations." Neither does it allude to " Fellows of the Royal Society." Nor did Eva Fay return to " the United States, carrying with her this letter." Nor was it even addressed to Eva Fay. It is then impossible that this can be the letter to which Dr. Carpenter refers, and I demand that he prove the truth of his allegation by producing a copy of the "American newspapers" containing 2^. facsimile of a letter written by me answering his description, containing the words which he professes to quote from it, and justifying his defamatory remarks. In your issue of last week (p. 26) Dr. Carpenter says nothing about this facsimile letter, but lays stress on an article written by me ten months previously. Does he seriously mean that the publication in March, 1875, of an account of some test experi- ments is a breach on my part of his "bury-the-hatchet" offer made the following November ? I have evidently been labouring under a misapprehension as to what Dr. Carpenter meant when he proposed to " bury the hatchet" I supposed he intended to cease misrepresenting my views and falsifying my experiments at his public lectures, and never afterwards to repeat such calumnies on my scientific posi- tion as he had anonymously contributed to the Quarterly Review for October, 1871. It seems, however, that Dr. Carpenter really meant that I was no longer to go poaching on his own special preserve, and was to abstain for the rest of my life from writing even a private letter on a subject which he has investigated for more than thirty years, and about which he is now writing and lecturing with redoubled vigour. Dr. Carpenter refers to an offer made in May, 1875, " by Eva Fay's manager, that for an adequate sum of money the ' medium ' should expose the whole affair, " and he vouches for its truth by saying he has seen "copies of the letters." I can supply, not copies, but original letters. I have before me letters from Eva Fay, dated Birmingham, May, 1875, speaking bitterly of the temptations and persecution to which [she was being subjected to induce her to join in the scheme, to which she was no party. But how, may I ask, does an abortive conspiracy to complicate " six big guns'" prove that my "scientific tests" — which with all deference to Dr. Carpenter's " good authority " can not be evaded by a "dodge" — were useless, and that in spite of them Eva Fay cheated me ? I am weary of protesting against the imputation which Dr. Carpenter conveys in the words "scientific advocates of the system." I emphatically deny that I have ever advocated any "system" in connection with the phenomena ascribed to spiritualism. I have never for one moment doubted that this name has covered an enormous mass of fraud and trickery ; but being convinced that amidst all this falsehood — which it -is Dr. Carpenter's mission to denounce in the most fsrvid eloquence at command — there was a solid nucleus of fact, and believing that every unrecognised fact is a reproach to science, and every unin- vestigated phenomenon is a probable mine of discovery, I con- sidered myself not merely entitled, but almost bound in scientific honour, to attempt the solution of the question. My attempt to bring the so-called supernatural within the realm of fact, to turn the light of science on a problem that required investigation, has exposed me to many misrepresentations, but especially to the ire of Dr. Carpenter, who never tires of repeating every idle tale from hearsay evidence. I look back to the days of the alchemists, and find the very same kind of fraud, mysticism, and trickery, differing but little from the impostures of the present day. But then, as now, there were a few earnest students who detected the germs of truth amidst the ravings and juggleries of the gold makers ; they cherished these germs, and although the Dr. Car- penter of that period would doubtless have denounced those students as " scientific advocates of the system " of alchemy, and felt it his duty to " undermine " their reputations, they persevered through calumny and ridicule, and thereby laid the foundations of our modern science of chemistry. The readers of Nature have now before them ample illus- tration of the falsity of the accusations with which I have been persecuted for so many years. A calumny once born, said the Great Napoleon, can never be killed. I have, however, done my utmost to prove the groandlessness of the very serious charges Dr. Carpenter has brought against me, down to the grave indict- ments in your issue of last week (p. 26). There is not a single charge which Dr. Carpenter has ever brought against me that I am unable to answer with like completeness ; and, judging from long experience, I venture to say that any future charges he may bring will be equally unfounded. But I cannot, out of regard for your readers, to say nothing of the sacrifice of time, continue to defend myself from every petty accusation ; and unless really forced by some imputation too serious to pass over, this must be my last letter on a subject which to me involves painfully too much self-reference. 1 have been constrained, in self-defence, to speak in somewhat downright fashion, but Dr. Carpenter's industrious misconstruction has drawn this protest from me. Misstatements expressed in a few lines may require pages to refute them. A calumny which takes a minute to write may demand days to answer. Memories of half-forgotten occurrences have to be revived, conversations recalled, old letters hunted out, journals exhumed, and, in fact, as much time and trouble ex- pended as if getting up evidence for an important legal trial. So great a tax for so trivial a purpose is monstrous in its dispropor- tion, and I can waste on this fruitless discussion no more precious time — time stolen from my physical work in the laboratory, already too much curtailed by the pressure of outward business. November 10 William Crookes The latter half of Dr. Carpenter's letter in last week's Nature (p. 26) consists of almost verbatim extracts from his article in this month's Fraser, I beg to refer your readers to a reply to Dr. Carpenter's attack, and a full exposure of his false accusations against Mr. Crookes and myself, which, will appear in the next issue of that magazine. They will then see who has been led by "prepossession" to adopt "methods which are thoroughly un- scientific," and whose are "the statements which_ ought to be rejected as completely untrustworthy." Alfred R. Wallace Experiment on Fluid Films I am experimenting on the optical phenomena exhibited by thin fluid films in a state of vibration, .and have just obtained ISIov. 15, 1877] NATURE 45 some beautiful results, including the formation of fixed straight and curved coloured bands, arranged in symmetrical figures, and of pairs of colour-vortices rotating in opposite directions. Unless these results prove to have been already described, I shall shortly publish an account of my experiments. Sedley Taylor Trinity College, Cambridge, November 12 Expected High Tides In your "Notes" last week you say that you cannot understand why the burden of such predictions should fall solely upon Capt. Saxby. This is what many of the public also do not understand. Why does not, say, the Meteorological Ofifice take the matter in hand, and not leave it to some private individual ? There can be no doubt the forewarnings are often of the greatest service and have saved the public tens of thousands of pounds and prevented a great deal of niisery. What I think Capt. Saxby is to be blamed for is the desire — it may be only apparent — to make a mystery ot his predictions with the general public ; and what gives weight to this is the fact that the Astronomer- Royal and the heads of the Meteorological Office and Society do not offer the public any aid in what is a purely scientific and eminently practical subject, in which Londoners are more interested than in the transit of Venus, and quite as much as in the storm-warnings for the Channel. When in March, 1874, Capt. Saxby came forward and in an oracular way predicted a great tide on the 20th, he gave no reasons. This many felt was unsatisfactory. Knowing that it must result from the action of natural laws curiosity led me to investigate the matter, and I found that the subject of extraordi- nary tides was a matter of much simplicity ; that the chief factors reside in the moon with its varyinsj distances and declinations ; the next in the sun and the seasons ; the next in the winds and atmosphere ; and the next, perhaps, in the action of the planets, as Venus and Jupiter, the former of which we know affects the orbit of the earth, and both have probably some power in pro- ducing the atmospheric disturbances in the sun. With these factors I predicted a year in advance the extra- ordinary tide of November, 1875, which had escaped Capt. Saxby 's notice. I was also able to say that there are two un- usually high tides revolving through the year, exactly six-and-a- half synodic months apart, each forty-eight days after the same tide of the previous year ; that these with the preceding and succeeding tides are chiefly those which may with bad weather develop into extraordinary ones ; and that the next great one — a very giant among tides — will be on March 20, 1878. If Capt. Saxby has some knowledge on the subject which others have not, how is it he did not predict the unusually high tide of October 26 last, which happened when the moon was neither full nor new, nor in perigee ? Why it happened is somewhat of a mystery ; the only explanation I can suggest is, that the moon had her highest northern declination on that day, and that a barometric depression passed over the North Sea the previous day, both which would tend to heighten the tide. November 12 B. G. Jenkins The Towering of Wounded Birds Last season I fired at a song thrush at a distance of fifty yards, but the bird continued its course, as if uninjured, for upwards of 200 yards, when it suddenly "towered" in the air, and as suddenly fell to the ground. Upon examination the bird was found to have been shot through the lungs alone, and had bled internally, the throat being full of clotted blood. The head was totally free from any injury. I have known similar instances occur in the pigeon, swallow, and starling. In all these cases the head remained uninjured, and death occurred throjgh internal haemorrhage. In the case of the starling one pellet entered the spine ; the bird continued its course for a few yards, towered, and suddenly fell to the ground dead. Should you consider these instances bearing on the matter of sufficient importance for an insertion in Nature they may prove acceptable to those who are interested in the subject. Heeley, near Sheffield Charles Dixon Cruelty to Animals' Act and Physiological Teaching I AM desirous of knowing through your many readers if, amongst; physiologists, the belief is anything like general, that showing ixnder the microscope the circulation of the blood in a web of a frog's foot is a contravention of " The Cruelty to Animals' Act, 1876.'^ Dr. M. Foster, in his " Primer of Physiology " (Macmillan and Co., 1877), advises the reader to " go and look at it at once ; you will never know any physiology till you do ; " and some naturalists here say if no incision is made, the animal being merely tiei down, the exhibition of the phenomenon is quite legitimJite, while, on the other hand. Pi of. Huxley, in his paper before the Domestic Economy Congress (reported in Nature, vol. xvi. p. 234) states it as his opinion that a teacher is "open to the penalty of fine and imprisonment if he «j-« " a frog "for the purpose of exhi- biting one of the most beautiful and instructive of physiological spectacles. " It was this, the expressed opinion of so distinguished an authority as Prof. Huxley, which caused me first to doubt the teacher's right to exhibit the experiment, and it is because of the differences of opinion I have mentioned that I seek to know through your columns, if a teacher is or is not at liberty to illustrate the blood circulation by this harmless experiment. Frank W. Young High School, Dundee, November 12 Smell andtHearing in Moths Numbers of moths, of many different species, are attracted into my room on summer evenings by the light ; and they are fond of resting on the lamp shade. One night I was using some very strong ammonia solution — and by way of driving them off I held a 3-ounce bottle of it with the open mouth almost close to them. To my surprise they seemed quite unconscious of it as a smell ; they would bear it unmoved for a minute, or sometimes for two or three minutes, and they then merely walked an inch or two further away from it. I have since tried the experiment repeatedly, and with several different species ; but none of them seem to detect the presence of ammonia except as a man might detect the presence of carbonic acid or of nitrogen in excess, that is, by their effects on his system generally. The common black and white " magpie moth," it is well known, often feigns death when captured. I caught two, one after the other ; both pretended to be dead, and I laid them gently on the table a few inches apart. They had remained motionless for ten minutes, when I took up a wine glass by the stem, and gave it one sharp stroke with a pencil, about six inches away from them. Both moths flew off at the instant the sound was heard. I repeated this many times with the same result — both with these and with other individuals of the sime species; and I also found that merely holding the glass near them and waving the pencil about noiselessly, did not arouse them. Loughton J. C. Bees Killed by Tritoma In a friend's garden here where there are quantities of Tri- tomas or "red-hot-pokers," hundreds of bees have been this year destroyed by them. The honey produced by the flower is very abundant, and the bees enter the tube of the corolla to get at it ; but the tube, which is only just large enough at the mouth, tapers gradually, and so the bee gets wedged in and cannot extricate itself. I saw numbers so caught, some in the fresh flower, while others remained in the completely withered and decaying blossoms. Perhaps it may be due to the fine warm days we have had this autumn, inducing the bees to work too late after our native honey-producing flo wers have been destroyed by the wet and frosts ; or is it a regular thing which happens every year ? If so bee-keepers should discourage the Tritoma, or set to work to select varieties with flowers large enough not to kill their bees. Alfred R. Wallace Dorking, November 3 Lecture Experiment The experiment described below illustrates in a very striking manner the particular instance of the "conservation of energy " exhibited by the equilibrium of liquids of unequal densities, in communicating vessels. The apparatus consists of a two-necked bottle, having in one neck a very strong glass tube half a metre, or more, in length, and terminating above in a funnel of 200 c.c. capacity, while its lower end nearly reaches the bottom of the bottle ; in the other neck is a piece of glass tube, drawn to a jet, and passing only a short distance into the bottle. As the pressure inside the appa- 46 NATURE {Nov. 15, 1877 ratus is considerable, the corks by which these tubes are fixed must fit very tightly. In using the arrangement the bottle is filled with water, the jet is then closed with the finger, and the fiinnel, which should be supported on the ring of a retort stand, is filled with mercury ; on removing the finger firom the jet the mercury falls into the bottle, expelling the water which rises in a fountain to a height depending upon that of the column of mercury, but rather less than is theoretically possible, the height of the fountain being ten or eleven times that of the fall of mercury. By employing mercury as the falling liquid in Hero's fountain a similar increase of effect may be obtained with that apparatus. W. A. Shenstone Fownes' "Manual of Chemistry" In my review of Fownes' "Manual of Chemistry" are two mistakes which I beg to correct. On page 25, line i, read improbable instead of improvable ; and line 6, dimorphides instead of isomorphides. The Reviewer OUR ASTRONOMICAL COLUMN The Transit of Mercury, May 6, 1878.— The transit of Mercury, which will occur on May 6 in the ensuing year, is the last during the present century in which the planet can be observed upon the sun's disc for any length of time in this country, and on that occasion the nearest approach of centres will take place only half an hour before sunset ; owing, however, to the long dura- tion of the transit, 7h. 35m. geocentric, Mercury will have been upon the disc more than four hours and a quarter when the sun sets. Reducing to Greenwich by the Nautical Almanac data it appears the first external contact will occur at 3h. lom. 58s. mean time, and the first internal contact at 3h. 14m. 4s., or the planet will be 3m. 6s. in wholly entering upon the d'sc. The least distance of centres will occur at 7h. om., and sun-set at 7h. 29m. The duration of the transit is longer than in any other of this century, or indeed than in any one that has occurred since the year 1756. Up to the present year twenty-four transits of Mercury have been more or less observed ; in this number are included that of 1631, November 7, predicted by Kepler, when the planet was seen upon the sun's disc for the first time by Gassendi, at Paris, who observed on the dark- chamber method — by allowing the sun's light to pass into the room through a small aperture in the window, and throwing his image upon a white screen ; that of 165 1, November 3, imperfectly seen by Shakerley at Surat, and that of 1707, May 6, which was observed through clouds by Roemer at Copenhagen near the egress. Of these twenty-four transits it is singular that only ei^Jit have taken place at the descending node or in May, as will be the case next year. Two-thirds of the number have therefore occurred in November, when we might have expected the hindrances to observation to have operated unfavourably in these latitudes. Of the three transits of the present century subsequent to 1878, that of 1881, November 7, will be wholly invisible in this country, the ingress taking place at loh. i6m. and the egress at ish. 37m. ; in the transit of 1891, May 10, the egress occurs soon after sun-rise ; and in that of 1894, November 10, it occurs near sun-set. The reader who is curious respecting the transits of Mercury in the next century may consult a communication from the Rev. S. J. Johnson to the Royal Astronomical Society in the Monthly Notices, vol. xxxvii. p. 425 ; and for an account of Gassendi's long watch for the transit of 163 1, and his successful observation of it, he may be referred to Prof. Grant's classical work, the " History of Physical Astro- nomy." Nova Cygni, 1876.— Prof. Julius Schmidt mentions that the star which he first remarked on November 24, 1876 (and which is not found in the Durchmusterung) diminished very regularly from JiUnuary to August ot the present year ; it exhibited none of the slight oscilla- tions in brightness which are still seen in T Coronae, and we may add in other " Novas." With the Athens re- fractor he has observed three small stars near the variable, with the following differences of right ascension and declination : — 13m J/ = Nova - i*o Nova — 45 13 s= „ -1-6 .. „ - 81 I2-S x^ „ +4-6 „ -h 20 It will be remembered that this star suddenly shone out of 3'4 magnitude, and had diminished to the limit of naked- eye vision soon after the middle of December. Its mean place for i88o'o is in R.A. 2ih. 36m. 59'9S., N.P.D. 47° 42' 16". Comet 1873, IV. — M. Raoul Gautier has worked out definitive elements of the comet discovered by M. Borrelly on August 20, 1873, and finds the observations best repre- sented by an ellipse with a period of 3,27 7§ years, the probable errors of perihelion distance and eccentricity limiting the period between 3,012 and 3,585 years. This comet, however, was observed for one month only, or through an orbital arc of only 58°, and such results of calculation in the present case are not perhaps to be allowed any great weight. There are many other comets which we imagine would better have repaid the labour expended by M. Gautier upon Comet 1873, IV. Express- ing his best paf-abolic elements in the manner adopted in catalogues of comet-orbits, we have the following figures : — Perihelion Passage, 1873, September 1083679 M.T. at Berlin, Longitude of perihelion 36 48 40 ) „ ^ j, „ ascending node ... 230 38 4 J ^^-^^^ '*73 o ,, inclination 84 o 50 Log. perihelion distance 9 '899956 Motion — retrograde. Minor Planets. — A remark in this column some time since upon the probability of several discoveries of so- called new planets proving to be observations of bodies previously detected, appears to be justified by recent experience. Thus the object announced as a new planet by Prof. Watson and M. Borrelly in August last was shown by Herr Knorre, of Berlin, to be identical with No. 141, detected by M. Paul Henry at Paris, on January 13, 1875, and it is now stated that the small planet remarked by Herr Palisa at Pola on October 2 is reaUy No. 161, which was discovered by Prof. Watson on April 18, 1876, and received the name Athor. As was to be expected from the rapidity with which discoveries of small planets have succeeded one another of late years, calculation is now considerably behind observation, and we are still without published elements of a number of the bodies lately brought to light. — Prof. Peters states that he has proposed the name Idunna for the planet discovered by him on October 14, which is No. 175, a name which he says will be understood by those members of the " Astronomische Gesellschaft " who, at their late meeting at Stockholm, participated in the hospitality of " Ydun." — There is now a strange confusion of mytho- logies and systems of nomenclature in the minor-planet group, a state of things that at one time might have been readily avoided. THE ROYAL DUBLIN SOCIETY A SCHEME for the reorganisation of this society as ■^*- a branch of the National Museum of Science and Art established by the Government has been under con- sideration for some time, and a report of the council on the subject was submitted to the society at its meeting on November 8. The scheme includes a recommenda- Nov. 15, 1877] NATURE 47 tion in favour of the amalgamation of the agricultural department of the society and the Royal Agricultural Society, under the title of the Royal Irish Agricultural Society ; after some discussion the report was carried. The following are the principal points involved in the reorganisation : — In accordance with the agreement entered into with the Government, the principal conditions of which are embodied in the "Act for the Establishment in Dublin of a Science and Art Museum and the Development of the Library of the Royal Dublin Society into a National Library," the property of the society in land, buildings, and collections has passed into the possession of the Government. The society will, in accordance with such agreement, receive the sum of 10,000/., which will be in- invested in such security as, subject to the approval of the Treasury, may be selected ; it will continue to be provided with the requisite accommodation in Leinster House ; the members will have free access to the several departments as heretofore, whilst the existing members, as well as all those who shall be admitted before January i next, will have the right to borrow books from the National Library. In order to assist in the more com- plete development of that part of the society's work which is devoted to the promotion of science and the useful arts, it has been arranged that all the scientific serials and transactions of learned societies, as well as all duplicates in the library, shall remain the property of the society ; the Lecture Hall and Laboratory will be reserved for its use ; and the collections in the Botanic Garden and Museum of Natural History will be available as for- merly for the illustration of papers read before the society. The most important condition, however, for the success- ful prosecution of the society's scientific work, pure as well as applied, is that for five years the cost of printing the scientific papers read before the society will be de- frayed by the Government. Concessions equally favour- able have been obtained for the agricultural department. Thus in lieu of the premises around Leinster House, which will be required for museum buildings, &c., the Government has undertaken to provide accommodation for agricultural shows elsewhere, and to reimburse the society for any pecuniary loss it may sustain in conse- quence of the change of site from the city to the suburbs. In order to develop the scientific work of the society, and thus secure to the fullest extent the great advantage of having the scientific papers read before it, printed, the Committee of Science have submitted a scheme for the complete reorganisation of the department under their superintendence. Thus, the meetings for the discussion, of subjects connected with science pure and applied will be held in these sections : — i. For the physical and ex- perimental sciences. 2. For the natural science, includ- ing geology and physical geography. 3. Science applied to the useful arts and industries. The papers to be read at these sectional meetings will be published in 8vo, as the Scientific Proceedings, the more important to be published in 410, under the title of " Transactions." In order to consolidate and economise both work and time other scientific bodies have been invited to associate themselves with the work of the sections, the meetings of which will be held simultaneously on the third Mon- day of each month, an invitation to which the Royal Geological Society and the Scientific Club have re- sponded. A special committee is now engaged in con- sidering the measures most advisable to adopt with regard to the future of the society, so as to maintain it as an object of attraction to the educated classes, and a pre- liminary report has been presented to the council, in which it is advised that in addition to the more complete organisation of the scientific department steps should be taken to render the reading-rooms more efficient, to establish a lending library for the use of future as well as present members, to arrange for the delivery of lectures for the elucidation of the latest discoveries in science, and to hold occasional conversaziones. According to one of the conditions contained in Lord Sandon's letter of February 9, 1876, the National Library will be placed under the superintendence of a council of twelve trustees, eight of whom are to be nominated by the Royal Dublin Society and four by the Government. Then followed the Report of the Committees of the Royal Dublin Society and of the Royal Agricultural Society on the subject of amalgamation, which, as we have said, was adopted. The two societies will to some extent remain connected ; the Agricultural Society, Lord Powerscourt stated, would be a branch of the Royal Society, though under different management. aV THE EOCENE FLORA OF BOURNEMOUTH DURING this last summer and autumn I have seized several opportunities of continuing my examination of the Bagshot Beds of Hampshire and the Isle of Wight, some of the results of which I think may interest your readers. This series is, as is now well known, of great importance from the fact of its being almost the only series from the tertiaries whose absolute relative geological age is positively known, it being under and overlapped on the mainland by the London clay and Bracklesham beds respectively, whilst in the Isle of Wight, occurring in a complete series of eocene strata, upheaved vertically, its true position is even still more plainly seen. It is further important as exhibiting in gradual sequence the change from an upland to a swamp flora, and represents very fairly the local flora of a long period and of an entire continent that has passed away. Of the richness and com-, pleteness of the flora an idea may be formed from the fact that I can reckon in my own collection not less than 10,000 selected specimens, many of large size, exclusive of twice that number which I have discarded, whilst there are also local collections at Bournemouth, a splendid series in the Cambridge Museurn, and a scarcely less important one from Alum Bay, at the British Museum. But perhaps the most valuable discovery — to the botanist, at all events — is that of various beds containing well-preserved fruits above the horizon of the leaf-patches, identifiable with fruits from Sheppey which are found in the London clay, and therefore below the leaves. We thus appear to have at Bournemouth the leaves of trees which may be descended from those whose fruits are imbedded at Sheppey. The assistance, it will be readily seen, of the Sheppey fruits will be of the greatest value in deter- mining the genera of the Bournemouth leaves and flowers. At Bournemouth about sixteen kinds of fruit may be collected in the seed-beds just mentioned, including Nipadites, Hightea, Cucumites, and Petrophiloides, quite sufficient to establish the fact that no break took place in the succession of the London clay flora. The number of forms also common to Bovey Tracey is worthy of note. The most abundant fern at either locality is Pecopteris li^nitum (now believed to be an Osmunda). Palmacites daemonorops of Heer, from Bovey, is no other than the Cactus of which I have frequently made mention. The dicotyledons of Bovey ascribed to Laurus, Ficus, Daphnogene, Dryandroides, &c., appear also to be identical with those of the Bagshots, and it is therefore not at all improbable that the miocene age of the Bovey Tracey beds, determined, as it seems to me, on most slender grounds, will have to be reconsidered. The extremely local distribution of the leaves in patches, each with its distinguishing group of plants, has again in fresh instances come prominently under my notice. At Studland, in one bed, fan palms with a three-foot radius lie massed together, but in a decomposed state ; and I only succeeded by using the utmost care in extracting one specimen showing the full length of the leaf. At 48 NATURE \_Nov. 15, 1877 Bournemouth a small bed of dark clay was found full of leaves of feather palm, crossing each other in every direc- tion ; the tip of a frond in my collection measures four feet in length, by three feet broad. Amongst other interesting specimens is a Smilax leaf of larger dimensions than any now living, and a twig of Dryandra, with many leaves attached, from Alum Bay, which unites in itself several of M, Watelet's species from the Gr^s du Soissonnais. The discovery of a finely preserved neurop- terous wing, and of two apparently hemipterous abdomens, are of interest in connection with the large series of insect remains from Gurnet Bay, Isle of Wight, lately deposited in the British Museum. The history remains to be written| of the subsidence of the great continent, whose further limits Edward Forbes surmised are yet traceable in the banks of Gulf Weed, ranging between the 15th and 45th parallels. Many, howevei", have written on Atlantis, but lacking the direct proof of its former existence in comparatively recent times, which has since come to light. The disappearance of almost an entire continent, is not a more startling proposition than the elevation of the Alps, Pyrenees, Apennines, and Carpathians, over whose highest summits the sea rolled at this period. Of the history of this dis- appearance Bournemouth presents us with but a page, still a page full of meaning. The incoming and disap- pearance in succession of oaks and beeches, figs and laurels, palms and delicate ferns, the swamp-loving aroids and Eucalyptus, Chrysodeum and Osmunda, on the same spot ; the appearance in masses of the fruit of Nipa, which is stated by travellers to be found in brackish estuaries ; the incoming of shore crabs and mud-boring Crustacea, sea-shells and Flustra, shingle beeches and deeper sea deposits, are each well-marked stages in the history of the disappearance of this continent, whose existence at this and a later period may be gathered from the writings, made from diff"erent standpoints, of Prestwich, Godwin-Austen, Sorby, and many others. The Bourne- mouth and Sheppey vegetable [remains were brought down by one of the rivers draining this continent, which at a later period silted over the reptiles of Hordwell and the estuarine shells of the fluvio-marine series. That the oscillations which gradually led to the disappearance of the land, vestiges of which remain in Cornwall, the Channel Isles, Brittany, Madeira, &c., have not ceased, even in historic times, there is ample local evidence to show. This branch of the subject, however, is scarcely yet ripe for discussion, nor would space here allow it to be fully entered into. Baron Ettingshausen and myself are preparing a monograph upon the ferns of this flora which I hope very shortly to place in the hands of the Palasontographical Society. J. s. Gardner THE TELEPHONE A T the Society of Telegraph Engineers on the evening -^-*- of October 31 a lecture of great interest was given by Prof. Graham Bell on the Telephone, with the inven- tion and improvement of which his name is so intimately connected. The lecture was largely illustrated by dia- grams, to which Prof. Bell: made constant reference, and with these illustrations will be published at length in the forthcoming part of the Journal of the Society. We have already given a full account of the telephone and its prmciples, and will only now refer to some of the mteresting episodes which occurred in the course of Prof. Bell's experiments. Prof. Bell's account of his experiments for devising methods of exhibiting the vibrations of sound, specially ^r use m teaching the deaf and dumb, is very interesting. For some time he carried on experiments with the mano- metnc capsule of Koenig, and with the phonautograph of Ldon Scott He was led to the idea of constructing a phonautograph modelled closely on the mechanism of the human ear, and at the suggestion of Dr. C. J. Blake, he made use of the human ear itself, a specimen of which was prepared by Dr. Blake, for conducting these experi- ments. It occurred to him that if a membrane as thin as tissue paper could control the vibration of bones that were, compared to it, of immense size and weight, why should not a larger and thicker membrane be able to vibrate a piece of iron in front of an electro-magnet, in which case the complication of steel rods in his first form of telephone could be done away with, and a simple piece of iron attached to a membrane be placed at either end of the telegraphic circuit. The form of apparatus he was then employing for pro- ducing undulatory currents of electricity for the purposes of multiple telegraphy he describes thus : a steel reed was clamped firmly by one extremity to the uncovered leg of an electro-magnet, and the free end of the reed projected above the covered leg. When the reed was vibrated in any mechanical way, the battery current was thrown into waves, and electrical undulations traversed the circuit, throwing into vibration the corresponding reed at the other end of circuit. He immediately proceeded to put his new idea to the test of practical experiment, and for this purpose he attached the reed loosely by one extremity to the uncovered pole of the magnet, and fastened the other extremity to the centre of a stretched membrane of goldbeater's skin. He presumed that upon speaking in the neighbourhood of the membrane it would be thrown into vibration and cause the steel reed to move in a similar manner, occasioning undulations in the electrical current that would correspond to the changes in the density of the air during production of the sound ; and he further thought that the change of the intensity of the current at the receiving end would cause the magnet there to attract the reed at that end in such a manner that it should copy the motion of the reed at the transmitting end, in which case its movements would occasion a sound from the membrane there similar in timbre to that which had occasioned the original vibration. The results, however, were unsatisfactory and discour- aging. With a reduction, however, in the size and weight of the spring employed, distinctly audible effects were obtained. " I remember," Prof. Bell said, " an experi- ment made with this telephone, which at the time gave me great satisfaction and delight. One of the telephones was placed in my lecture-room in the Boston University, and the other in the basement of the adjoining building. One of my students repaired to the distant telephone to observe the effects of articulate speech, while I uttered the sentence, 'Do you understand what I say?' into the telephone placed in the lecture-hall. To my delight an answer was returned through the instrument itself, articu- late sounds proceeded from the steel spring attached to the steel membrane, and I heard the sentence, * Yes, I understand you perfectly.' It is a mistake, however, to suppose that the articulation was by any means perfect, and expectancy no doubt had a great deal to do with my recognition of the sentence ; still, the articulation was there, and I recognised the fact that the indistinctness was entirely due to the imperfection of the instrument." After a time he produced a form of instrument which served very well as a receiving telephone ; and it was in this condition his invention was exhibited at the Centennial Exhibition in Philadelphia. It was in this condition also that Sir William Thomson exhibited the instrument to the British Association in Glasgow. In pursuing his investigations Prof. Bell has come across many interesting facts which we regret we cannot refer to in detail. It has long been known that when an inter- mittent current of electricity is passed through the coils of an electro-magnet a musical tone proceeds from the magnet. " I have discovered," he said, " that these sounds Nov. 15, 1877] NATURE 49 are not due wholly to sudden changes in the magnetic con- dition of the iron core, as heretofore supposed, but that a portion of the effect results from vibrations in the insulated copper wires composing the coils. An electro-magnet was arranged upon circuit unto an instrument for inter- rupting the current, the rheotome being placed in a distant room so as to avoid interference with the experi- ment. Upon applying the ear to the magnet a musical note was clearly perceived, and the sound continued after the iron core had been removed from the coils. The effect may probably be explained by the attraction of the coils for one another during the passage of the galvanic current and the sudden cessation of such attraction when the current ceased. It is probable, too, that a molecular vibration is occasioned in the conducting wire by the passage of an intermittent current. I have found that very distinct sounds proceed from straight pieces of iron, steel retort-carbon, and plumbago, when an intermittent current is passed through them." When a powerful current is passed through the body a musical note can be perceived when the ear is closely applied to the arm of the person experimented upon. The sound seems to proceed from the muscles of the fore- arm and from the biceps muscle. Mr. Elisha Gray has also produced audible effects by the passage of electricity through the human body. An extremely loud musical note is occasioned by the spark of a Ruhmkorff's coil when the primary circuit is made and broken with suffi- cient rapidity ; when two rheotomes of different pitch are caused simultaneously to open and close the primary circuit a double tone proceeds from the spark. A curious discovery has been made by Prof, Blake. He constructed a telephone in which a rod of soft iron, about six feet in length, was used instead of a permanent magnet. A friend sang a continuous musical tone into the mouth-piece of a telephone, which was connected with the sofc iron instrument alluded to above. It was found that the loudness of the sound produced In this telephone varied with the direction in which the iron rod was held, and that the maximum effect was produced when the rod was in the position of the dipping needle. This curious discovery of Prof. Blake has been verified by Prof. Bell. " Prof. Peirce has observed the most 'curious sounds produced from a telephone in connection with a tele- graph-wire during the aurora borealis ; and I have just heard of a curious phenomenon lately observed by Dr. Channing. In the City of Providence, Rhode Island, there is an over-house wire about one mile in extent with a telephone at either end. On one occasion the sound of music and singing was faintly audible upon one of the telephones. It seemed as if some one were practising vocal music with a pianoforte accompaniment. The natural supposition was that experiments were being made with the telephone at the other end of the circuit, but upon inquiry this proved not to have been the case. Attention having thus been directed to the phenomenon, a watch was kept upon the instruments, and upon several subsequent occasions the same fact was observed at both ends of the line by Dr. Channing ar.d his friends. It was proved that the sounds continued for about two hours, and usually commenced about the same time. A searching examination of the line disclosed nothing abnormal in its condition, and I am unable to give you any explanation of this curious phenomenon. Dr. Channing has, how- ever, addressed a letter upon the subject to the editor of one of the Providence papers, giving the names of such songs as were recognised, with full details of the observations, in the hope that publicity may lead to the discovery of the^ performer, and thus afford a solution of the mystery." Prof. Bell referred to some experiments made by Mr. F. A. Gower and himself to show the slight earth connection required to establish a circuit for the telephone. " One experiment which we made is so very interesting that I must speak of it in detail. Mr. Gower made earth connection at his end of the line by standing upon a grass plot, whilst at the other end of the line I stood upon a wooden board. I requested Mr. Gower to sing a con- tinuous musical note, and to my surprise the sound was very distinctly audible from the telephone in my hand. Upon examining my feet I discovered that a single blade of grass was bent over the edge of the board, and that my foot touched it. The removal of this blade of grass was followed by the cessation of the sound from the telephone, and I found that the moment I touched with the toe of my boot a blade of grass or the petal of a daisy, the sound was again audible." Prof. Bell concluded as follows : — " The question will naturally arise, through what length of wire can the telephone be used .'' In reply to this I may say that the maximum amount of resistance through which the undu- latory current will pass, and yet retain sufficient force to produce an audible sound at the disturbed end, has yet to be determined ; no difficulty has, however, been expe- rienced in laboratory experiments in conversing through a resistance of 60,000 ohms, which has been the maximum at my disposal. On one occasion, not having a rheostat at hand, I may mention having passed the current through the bodies of sixteen persons, who stood hand in hand. The longest length of real telegraph line through which I have attempted to converse has been about 250 miles. On this occasion no difficulty was experienced so long as parallel lines were not in operation. Sunday was chosen as the day on which it was probable other circuits would be at rest. Conversation was carried on between myself, in New York, and Mr. Thomas A. Watson, in Boston, until the opening of bi;siness upon the other wires. When this happened the vocal sounds were very much dimi- nished, but still audible. It seemed, indeed, like talking through a storm. Conversation, though possible, could be carried on with difificulty, owing to the distracting nature of the interposing currents. " I have had the opportunity of testing the telephone upon the artificial cable owned by Sir William Thomson. No difficulty was experienced in conversing through the equivalent of 120 miles of submarine cable. Vocal sounds were audible when the equivalent of the whole Atlantic cable was interposed between the two telephones, but the sounds were so faint that conversation could not be carried on. Songs that were sung into one telephone were readily recognised at the other end of the circuit, and the articulation of pre-arranged sentences was readily recognised. That the sounds were electrically produced was evident from the fact that they ceased when the cir- cuit was broken and when the coils of the telephone were short circuited. No difference was observed between the pitch of the note which was transmitted through the arti- ficial cable and the same note when transmitted directly through the air. The artificial cable experimented upon had four times the resistance of the Atlantic cable, and one-fourth its electrostatic capacity. I am informed by my friend, Mr. Preece, that conversation has been success- fully carried on through a submarine cable, sixty miles in length, extending from Dartmouth to the Island of Guernsey, by means of hand telephones." In a lecture on the 8th inst. at Glasgow, Prof. Bell, referring to the use of the telephone in mines, pointed out how the instrument might be of the greatest service in determining whether the ventilation of a mine was perfect or not ; for by listening to the telephone, if the mine was in good order, a little sound could be heard every moment. AFRICAN EXPLORATION MR. STANLEY'S letter and the map in the Telegraph of Monday enable us to realise somewhat more fully the nature and extent of the discoveries made by the 50 NATURE \_Nov. 15, 1877 intrepid traveller. Mr. Stanley is bent on calling the great river, so much of which he has explored, by the name of Livingstone. As a rule we think it a mistake to change native geographical names where these can be satisfactorily ascertained. In the case of the Lualaba- Congo, however, the river seems to have quite as many names as there are tribes or villages on its banks, and it would be a happy solution of the difficulty to confer upon it the most memorable name among African explorers. Mr. Stanley himself has taken great pains to obtain accu- rately the native names of tribes and places, and he animadverts with severity on geographers for crowding the map of Africa with names that probably correspond to nothing. For this they cannot be greatly blamed, neither need he be too hard on previous travellers for misunderstanding the significance of native words. A glance at the map, notwithstanding that it is based to some extent on conjecture, shows at once the vast import- ance of Mr. Stanley's discovery. Great tributaries join the main river from both sides, and we are assured there are many more besides these shown on the map. For more than 800 miles of its course, above the Yellala Falls, the river looks more like a long winding lake than any- thing else, forming a magnificent channel for navigation. Above the upper cataract, again, about the equator, many other long reaches are capable of navigation, while the affluents will afford over 1,200 miles, and perhaps much more. Some idea of the increasing magnitude of the river below Nyangwe may be obtained from Stanley's statement that at Nyang we the volume is 124,000 cubic feet per second, while Behm's calculation on the basis of Tuckey's trustworthy observations makes its volume at the mouth to be 1,800,000 cubic feet per second. Poor Tuckey comes in for a share of Stanley's castigation, because, according to Stanley, the former mistook the number of stages of the Yellala Rapids ; even if Tuckey was a little out in his counting, which we doubt, he will still be found to have been, all circumstances considered, an accurate observer. Many points, also, in connection with the map, show how true was Living- stone's geographical instinct^ and how near the truth his inferences came from the information obtained from the Arabs and natives. Stanley is probably right in conjec- turing that the Aruwimi, coming from the north-east, and joining the Livingstone a little north of the equator, is the Welle, and that the Ikelemba is the lower course of the Kasai. The water of the latter is of the colour of tea, and does not thoroughly mingle with the main stream until after 130 miles below the confluence. The banks of the great river are thickly populated by what appear to be industrious people living in extensive and well laid out towns, and naturally jealous of intruders. The three most powerful tribes on the middle and lower rivers are the Wa-Mangala, the Warunga, and the Wyanzi. The Livingstone, Mr. Stanley found, is subject to periodi- cal rises mainly owing to the rains, and varying from eight to fifty feet. The entire length of the Livingstone Mr. Stanley calculates at 2,900 miles, and its basin at 860,000 square miles. The extreme sources of the Bemba Lake, from which the Luapula flows, are in 33° E. long. Lake Bemba, or Bangweolo, Stanley states — and there appears to be good ground for the belief — is the residuum of an enormous lake that in very ancient times must have occupied an area of 500,000 square miles, " until by some great convulsion the western maritime mountain chain was riveii asunder, and the Livingstone began to roar through the fracture." As to the "great convulsion" and the " fracture," geologists may be able to decide when they are in possession of full information as to Mr. Stanley's observations. Nyangwe, Mr. Stanley informs us, is in 4° 16' S., and 26° 5' E. ; but by an unaccount- able mistake in another place he gives the latitude as 26° 15' 45", and that, too, while pointing out, in his peculiar way, a slight mistake in the position on Stanford's map of 1874. The position then was perfectly correct according to the data, and in the latest editions the position is exactly as Stanley gives it. Mr. Stanley insists on the importance of the river as a commercial highway, the country traversed by it being abundantly rich in products that would find a ready market in Europe. Naturally, on Monday night, Africa was the burden of the president's address at the opening of the Geographical Society. Sir Rutherford Alcock in- sisted that it now remained with the merchant, aided if need be by Government, to open up Africa still further. Indeed the country is now being attacked by national and private expeditions on all sides, and if a basis for minute explo- ration were formed by trading stations under government sanction and regulation, along the Livingstone, our know- ledge of the country would grow rapidly, and the benefits to commerce would be incalculable. Only, however, could the natives have fair play by governmental regu- lation of private enterprise. There is no danger of extinction for the native African, and it would be both prudent and just to protect him from the horrible cruelties at which Mr. Stanley hints in the conclusion of his letter. It is worth noticing that in the map the Lukuga runs boldly from Lake Tanganyika and joins the Lualaba, and the source of the Alexandra Nile is brought to near 4° south on the east side of the lake. According to latest intelligence Mr. Stanley is at the Cape wanting to get his followers sent back to Zanzibar. In his letter in yesterday's Telegraph he gives an inter- esting account of his companion, Frank Pocock, of whom he speaks in the highest terms, and whose death is a real loss to African exploration. The Daily News Alexandria Correspondent writes (on the 5th) that Signori Gessi and Matteucci have just started from Cairo for Khartum, via Assouan, by the Nile, instead of taking the shorter route by the Red Sea to Massowa. They are provided with the newest and most improved scientific instruments, and having promised to keep up constant communication with the Geographical Society at Rome, interesting accounts of their movement and progress will be looked for. MODERN TORPEDO WARFARE n^WO elements have contributed to make torpedo -*- warfare what it is : electricity and the new explosive compounds. It is true that in the Whitehead or fish torpedo recourse is had only to the latter of these, but it is the sole material exception, and all the mischief effected by this branch of marine warfare has been, so far, the result of electric torpedoes. Both on the Danube and in the last American war, when no less than twenty-five ships were sunk by the Confederates, the electric torpedo has worked extensive injury, and it is no wonder therefore that a keen interest should be taken in all that pertains to so novel and destructive a method of kiUing and wounding. We have called the torpedo a novel weapon, and the instruments that go by the name to-day undoubtedly are so. At the time of the Crimean war, we had to do with torpedoes of a kind ; nay, even so far back as the beginning of the seventeenth century, floating charges, called petards, were employed, but these were of too insigriificant a nature to merit attention. The " infernal machines" strewn in the Baltic by the Russians twenty years ago were small canisters of powder containing by way of igniting arrangement a mixture of chlorate of potash and sugar, together with a glass bulb with sul- phuric acid ; and the latter, escaping from its envelope when this was broken by a shock or collision, brought about an immediate explosion. These mechanical tor- pedoes had two disadvantages ; the igniting arrangement was of such a character that it could be set in action just as well by friend as by foe, and the explosion of the gun- l\^ov. 15, 1877] NATURE 51 powder was insufficient to effect any material injury. All this has been remedied. Electricity is nowadays em- ployed as the igniting agent, and those terribly violent explosives, gun-cotton and dynamite, replace the com- paratively innocuous gunpowder. Electric torpedoes may be broadly divided into two classes : offensive and defensive torpedoes. The latter are employed for the protection of harbours, channels, and roadsteads ; the former, in the shape of drifting or spar- torpedoes, are carried to the attack in small swift-sailing steam-launches. In this country we are favourably dis- posed to the employment of compressed gun-cotton in our machines, while on the Continent they seem to entertain a predilection for nitroglycerine, or rather dynamite. "Both compounds are what chemists term nitro-compounds, in contradistinction to gunpowder, which comes under the class of nitrate-compounds, and appear to exercise an ex- plosive force'of almost similar violence, measuring the sub- stances weight for weight. Compressed gun-cotton, we need hardly say, is cotton yarn acted upon by nitric and sulphuric acids and then pulped and washed, so that the result is a finely-divided mass which may be made to assume any shape or form. As a rule the material is pressed into cakes of disc-like form, which weigh from a few ounces to a pound, and while still wet the slabs are stored away in the magazines. In this moist condition Fig. I. — Fish Torpedo exploding against a ship. the compressed pulp is not only non-explosive, but actu- ally non-inflammable, except one possesses the key to its detonation. This is nothing more than a dry cake of the same material, or as the latter is termed in military par- lance, a "primer," which on being detonated by a few grains of fulminate, brings about the explosion of any wet gun-cotton in its immediate neighbourhood. Thus if simply a net is filled with gun-cotton slabs and thrown into the sea, the whole charge may be ignited by a primer contained in a waterproof bag having an electric fuze and wire attached. The possibility of communicating explosion in this way by vibration instead of by spark or flame is, too, as we shall presently see, the germ of a system of counter-mining, or torpedo annihilation, which bids fair to develop into a particularly effective means of defence against these terrible machines. Dynamite is similarly exploded to gun-cotton. The active principle in this case is nitro-glycerine, or, if you will, liquid gun-cotton, prepared by simply allowing glycerine to fall drop by drop into nitric acid. As a solid is usually more convenient to handle than a liquid, the use of pure nitro-glycerine has given way to dynamite, which may be described as siliceous earth impregnated with the explosive fluid. Dynamite and gun-cotton explode with something like four or five times the force of gunpowder, and for this reason a very destructive charge may be confined within a comparatively small space. Moreover they are peculiarly adapted to submarine mines, since nitro- glycerine is no more affected by water than gun-cotton ; and the old adage '' to keep your powder dry " does not apply to either of them. In the case of moored torpedoes which are connected with batteries to the shore or cany their own means of generating electricity, as in the Herz topedo of our German cousins, there is no limit to size, and machines containing as much as 500 lbs. of gun-cotton have, in fact, been constructed; but for a spar- torpedo, or in other words one which is thrust under an enemy's keel by means of a thirty-foot pole projecting from the prow of a launch, the charge must be con- siderably smaller, and for two reasons. A great weight at the end of such a lever could not be properly ma- nipulated, while the explosion, if the charge were a very large one, would destroy both the attacking and attacked. A big moored torpedo of 500 lbs. has been found, when sunk in thirty or forty feet of water, to be fatal to a strong ironclad if the latter happens to be within this distance of the source of explosion ; or, in other words, a cushion of water forty feet in thickness is not sufficient to secure the immunity of such a vessel. What would happen if this terrible volcano were to erupt — if we may use the word — in contact with the sides of an armoured ship, must be left to the imagination ; but despite Mr. Ward Hunt's opinion to the contrary, we do not think it would require Fig. 2. -A moored Torpedo exploding. 220 feet. Height of column 60 feet, base three such torpedoes successfully exploded, to bring our boasted Inflexible to grief. And in this opinion our readers, we suspect, will fully agree, when we inform them that a heavy torpedo like tltiis throws up a cone of water sixty feet in height, with a diameter at its base of no less than 220 feet. Such an heaving of waters, if it did not break the back of an ironclad, as there is every reason to suppose it would, must inevitably capsize her with- out more ado. But it is, of course, only on very rare occasions that such a monster torpedo could be brought to bear, and in all cases of attack the charge must needs be considerably less. The smaller Whitehead torpedoes, which, as our readers know very well, are narrow cigar- shaped weapons, that move through the water by the agency of compressed air, do not in all probability carry more than a 40 lb. or 50 lb. charge in the head, while a spar or drift torpedo of 100 lbs. is already as large as would be convenient to handle. At the same time either of these would quite suffice to fracture an iron plate several inches in thickness, and therefore be fatal, pro- bably, to any ironclad afloat, supposing there was no water-cushion between the craft and the torpedo. We have no definite information respecting the size or weight of the torpedoes which sank the Turkish monitor in the Matchin Canal, but as the expedition was hastily arranged and organised, the charges were, no doubt, not very large. The fish torpedo is a rare example of a comphcated apparatus coming into practical use, and its elaborate 52 NATURE {Nov. 15, 1877 construction and fine workmanship may be imagined when the reader is informed that the machines cost 500/. a piece to manufacture. The long tube is divided into three compartments : the head, which contains the explosive charge, the reservoir, in which the compressed air is stored, and the machinery by means of which the stored-up energy is converted into a propelling force. The air is compressed to the extent of 600 lbs. on the square inch, and to bring about this result an exceedingly powerful air-pump is necessary, which forms an addi- tional item of expense in the case of this torpedo. The latter when properly charged will do a journey of a mile, or mile and a half, underwater, the first 1,000 yards being got over at a rate of no less than twenty miles an hour, and if unaffected by tide or current, the machine will proceed in a perfectly straight direction. It floats at any distance under water that may be desirable, but is usually made sufficiently buoyant to swim at eight feet from the surface ; it explodes on striking any object, but the machine is so contrived that if it fails to strike, then it floats to the surface, and a trigger guard renders the fish at the same time innocuous, and permits of its recapture without risk. Ingenious as the little creature is, there has been, we repeat, no authenticated employment of it during the present war. On the Danube the spar-torpedo'alone seems to have been used against Turkish monitors. As in the case of the Thorny croft\aMn<^, of which we are to have a flotilla of thirty in the British navy, the torpedo is projected at the end of a spar, and is ignited either by concussion or by electricity. The Turkish ironclad at Matchin was the victim of two torpedoes of this class, the first of which, we are told, was ignited by the crew of the launch by electricity, and the other on concussion with the vessel attacked. These Russian torpedoes are said to be innocuous at a distance of ten feet from the seat of explosion, and hence those in the launch do not suffer much except from the water that is thrown into the air. From the fact that small batteries in the boat are used to fire the charges, we may safely conclude that their explosion is brought about by a platinum wire fuze, which, together with a few grains of fulminate, would determine the detonation of dynamite or gun-cotton. Each launch is provided with a pair of these spar torpedoes, carried, when not in action, on each side, running the length of the boat, and only on making an attack is one or other projected at the bow, the torpedoist being stationed behind a shield, or under an iron screen, where he can make his observations tolerably free from danger. In the case of moored torpedoes depending for their ignition upon electricity, many points of scientific interest have recently been brought to light. Some experiments undertaken in Denmark two or three years ago showed most conclusively that dynamite torpedoes cannot be placed close together without incurring the danger of one charge bringing about the explosion of others. A dyna- mite torpedo of 150 lbs. ignited in ten feet of water, was found capable of exploding other charges at a distance of 300 feet by the mere vibration imparted to the water ; so that in constructing coast defences with dynamite tor- pedoes it is absolutely necessary to keep them far apart from one another. Another point was also noted. A current of electricity, if it emanates from a powerful fric- tional electric machine, traversing one of a bundle of wires, will induce a current in the other wires, and thus bring about the explosion of torpedoes other than that which the operator on shore desires to ignite. It is these facts particularly which have led to the development of a system of counter-attack and have enabled our sailors to devise a means of defending themselves from the terrible sea-monsters. Both dynamite and gun-cotton are pecu- liarly sensitive to vibration — indeed their detonation, as we have seen, is brotight about by no other cause — and hence a captain of a man-of-war by exploding counter- mines in his vicinity may soon get rid of any lurking torpedoes lying in wait for him, at any rate if they contain a nitro-glycerine compound, and so speedily clear a way for his ship. This is certainly subject for ' congratulation, for it seemed at one time as if the poor sailor was absolutely defenceless against these submarine abominations. A crinoline of spars and wire rope may be employed to catch the fish torpedo and explode the vermin harmlessly in its toils, provided the ingenious brute is not a very large one, and the net is at some distance from the ship ; but heavy moored torpedoes have been hitherto con- sidered too dangerous to approach, so that marine coun- termining must prove invaluable. The spar or drifting torpedo cannot be dealt with by nets or booms alone, and in this case the only plan would seem to be to meet a^ tack with attack and beat off launches with other small boats. That all ironclads in time of war will have to be sur- rounded by lesser craft as a protection is a matter that we may now take for granted, as also that such vessels must be provided with some powerful means of illumina- tion— the electric light, for instance — to prevent swift, low-lying torpedo launches from approaching unperceived at night time. Special schools of instruction for acquainting officers with the science of electricity and explosives have for some time past been established, and there is indeed scarcely a naval power which has not paid attention to submarine warfare ; consequently we may expect to see future battles upon the sea carried on just as much under water as above it. In this country we have a torpedo school on board H.M.S. Vernon at Portsmouth, while at the Royal Naval College at Greenwich instruction in the experimental sciences now forms one of the most important items in the curriculum. France has its naval torpedo school at Boyardville, where both officers and seamen are made acquainted with the principles of submarine warfare. Germany, as all the world knows, practised torpedo war- fare to such good purpose seven years ago that the mag- nificent fleet of the French never once ventured to visit the coast of the Fatherland. Both at Kiel and at Wilhelms- haven are to be found torpedo depots and a well-orga- nised staff" of instructors. Lastly the news comes to us from Russia that the Czar has sanctioned the organisation of a distinct torpedo service, and two depots and instruc- tional schools are to be formed at Kertch and Cronstadt, whence torpedo appliances are to be issued for the defence of the Baltic and the Black Sea. NOTES Mr. Darwin will receive the honorary degree of LL.D. at Cambridge on Saturday next, at 2 p.m., at a congregation specially convened for the purpose. In the evening the annual dinner of the Philosophical Society will take place in the Hall of Clare College, when a brilliant gathering is expected to meet the illustrious visitor, among the non-resident guests being Profs, Huxley, Tyndall, and Parker, and Sir John Lubbock. The Postmaster-General of the German Empire is about to have an extensive series of experiments made with a view to the introduction of the telephone into the telegraphic service. Several hundred specimens of the telephonic apparatus manufactured by Siemens and Halske have been ordered. The French Ministry had granted a pension to the widow of Leverrier. Unfortunately the lady died, as we mentioned in our last number, before the first monthly instalment became due. It is hoped that a part of the pension will go, against ordinary rules, to the son and daughter of the astronomer. The Minister of Public Instruction has been authorised by si Nov. 15, 1877] NATURE 53 decree of the President of the French Republic to accept a sum of 8,000/., bequeathed by Madame Thuret, in order to establish at Antibes, in the Department of Alpes Maritimes, an agricul- tural station connected with the lectureship on Agriculture and Botany of the Paris Museum of Natural History. Mr. Park Harrison has completed the exploration of the galleries belonging to the "Cave Pit" at Cissbury — in which rune-like characters were found, in 1875 — and found that they communicate with galleries connected with other shafts, at distances of from 20 to 30 feet, on the north, west, and east sides. Mr, Harrison thinks there appears to be sufficient evidence that they were used for purposes of shelter or concealment long after they were originally excavated. One of the shafts last cleared out, was found to have been left in an incomplete state, as if the work had been for some reason inter- rupted. On the south of the cave pit, and immediately adjoining it, Mr. Harrison has discovered several small pits, the largest being 5 feet in diameter, and 4 feet 6 inches deep. All con- tained flint flakes, sling-stones, and a few bones. In some there were small ornaments, pots of good quality, bone combs, terra- cotta beads, and hard polishing-stones. In one pit there was an iron hook. The following testimony from so competent and disinterested an observer as Prof. Monier Williams to the necessity for syste- matic meteorological observation in India is valuable, and we hope will have weight with the proper authorities. In the last of his series of articles on his second tour in India, in the Ti/nes of November 7, Prof. Williams writes thus : — " One thing re- quires instant attention. The connection between agriculture, meteorology, and astronomy is now admitted on all hands, and no country in the world would be benefited more than India by systematic meteorological and astronomical observations carried on under Government direction. Much is already being done in this way. Yet I could only find one effective astronomical observatory, and that not adequately supported by Government, though I travelled from Cashmere to Cape Comorin. It is not generally known that from his observations of the present con- dition of the disc of the sun, in connection with various atmo- spherical phenomena, the Madras astronomer, Mr. Pogson, pro- phesied in 1876 a recurrence of the drought and famine in 1877." On Octohtxz^-weXea.tnkova.L'' Exploration, Signor D'Albertis and Prof. Od. Beccari left Genoa in the steamer Australia for a year's voyage round the world. They will first visit Egypt, and thence to India, China, and Japan, returning to Europe by New York. They intend to collect during their voyage birds, mammals, and insects for the museums of Italy, principally for that of Genoa. For several years past Major J. W. Powell, in charge of the United States Geographical and Geological Survey of the Rocky Mountain Region, has been paying particular attention in his researches, to the ethnology and philology of the American Indians ; and having received from the Smithsonian Institution an immense mass of material on this subject, collected during a period of many years, he has called to his assistance numerous experts for the purpose of preparing a series of memoirs on these topics. We have now a partial result of his labour in the first of a series of quarto volumes, entitled "Contributions to North American Ethnology," and published in most excellent style, with numerous illustrations, at the Government Printing-office. The present volume is occupied with the Indians of North-western America, embracing several papers by Mr. Dall and others on the tribes of Alaska and adjacent territories, and a number of vocabularies, principally by the late Mr. George Gibbs. Our readers may remember that last spring Capt. Burton made an expedition into the Land of. Midian, which lies to the south-east of the Gulf of Akaba, in the Red Sea. He was accompanied by a mining engineer, M. Marie, and the two explorers came upon traces of extensive mining operations, the ruins of ancient towns, and many other evidences of a flourishing mining district. They brought back specimens containing gold, silver, copper, and other metals, and were most sanguine as to their discovery. Capt. Burton is now again in Egypt, the Times' Alexandria correspondent writes, preparing another expedition to Midian. He is now determined to investigate thoroughly that biblical country of which he only got a superficial idea in his twenty-day visit last spring. His intention now is to penetrate to the mountains in the interior, and thoroughly satisfy himself as to their nature and capabilities. He estimates the distance under twenty days' march. It is a curious fact that these mines were known to the ancients so long ago as the time of Ramses HI., whose cartouche is inscribed on the Needle which is on its way to England. In the Harris Papyrus in the British Museum is a passage referring to the copper mines of Akaba. At the last meeting of the Russian Geographical Society, the Secretary gave some account as to this year's expeditions sent out by the Society. The results of Prshevalsky's expedition are a survey from Kuldja for 800 miles into the interior of the country, seven determinations of latitudes and longitudes, many baro- metrical measurements of heights along the route, a botanical collection of about 300 species, a zoological collection, numbering 85 mammalia, 180 species (500 specimens) of birds, 50 speci- mens of fishes, 150 reptiles, and 2,000 insects. The most im- portant objects in the collection are four skins of wild camel?. All the collections are now in Kuldja, and will be forwarded to St. Petersburg during the winter. About the end of August M. Pishevalsky' had started for Tibet. M. Potanin has returned without having penetrated far into the interior of Mongolia. He proposes now to go to the sources of the Yenissei. M. Mainoff has returned from his travels among the Mordva population of Eastern Russia with very valuable materials. He has obtained anthropological measurements according to the 1 26 queries of the programme, of 5 10 individuals, and he brings detailed answers on the queries of the programme as to the ethnographical and juridical customs of the Mordva, as well as numerous skulls, photographs, tools, and dresses. A RAILWAY official in Berlin was lately fined by the district courts for appending to his name the title of doctor juris utriusque, on the strength of a diploma from the University of Philadelphia. An appeal to a higher court resulted in a confir- mation of the sentence. Wk notice a very useful Russian work, just published by the St. Petersburg Committee of Primary Education, being a review of all works that have appeared in Russia in the department of primary instruction. The book, 640 pages, gives a complete catalogue of such'works, with critical notices on each of any importance, and it is sold at a very low price, for the use of primary teachers. A YOUNG schoolmistress of TIemcen (Algeria) has successfully passed her examinations before the Faculty of Aix for Bacca- laureate in Letters, and has been warmly congratulated by the Board. The statue of Lagrange, the celebrated mathematician, born in Italy, but a naturalised Frenchman, was erected last week in the hall of the Bureau des Longitudes. ;;; At a recent meeting of the Paris Academy of Sciences a letter from M. Fabre to M. Dumas was read, referring to an American vine which he had cultivated for a long time in the very heart of phylloxeric centres, but which has 54 NATURE [Nov. 15, 1877 escaped the least sign of infection. It flourishes under the most unfavourable circumstances, grows rapidly, and readily receives grafts from French vines. The French Association Poly technique, created in 1830, has just published its programme for 1877-1878. Lectures are given by this institution to working men] in each of the twenty municipal districts of Paris, and in almost every manufacturing district of France, For the first time the programme of lectures Is uniform, and special text-books are published at a'cheap rate under its authority. No salaries are given to teachers, and no fees taken from pupils. It is called "La Sorbonne de I'Ouvrier." All expenses are covered by voluntary contributions. M. Dumas, the perpetual secretary of the Institute has been elected 'pre- sident of the Association, He has filled this important position for a number of years. The Jardin d' Acclimaiation of Paris, as we recently stated, has received a family of Esquimaux, who are quartered alongside the Nubians, who were recently in London. They consist of three men, a woman, and two children, and have charge of a collection of phocas, white bears, and trained dogs. The customary Esquimaux huts have been erected for their accommo- dation, and their time is spent in the ordinary occupations to which they are accustomed in the Polar regions. The Societe d^ Anthropologie de Farts has appointed a commission to study these unusual visitors, consisting of Dr. Broca, president, and MM. Bordier, Dolly, Girard de Rialle, Mazard, and Topinard. The Ministry of Public Instruction has just established, in Paris, a " Bibliotheque L^niversitaire," containing all works appearing from the pens of the professors of the French University. Among the medals awarded by the Photographic Society in connection with their Exhibition, are one for the best micro- photograph, " Proboscis of a Blowfly," to Mr. Edward Viles, and a special medal to Mr. W, J, A. Grant for his Arctic Views. The Institution of Civil Engineers resumed its meetings on Tuesday. Among the papers announced to be read early in the session are, a " Review of the Progress of Steam Shipping during the last Quarter of a Century," by Mr. Alfred Holt, M. Inst. C.E. of Liverpool, whilst the latest development of electrical invention and its application to lighting purposes, will be discussed in a paper by Dr. Paget Higgs and Mi-. Brittle, Assocs, Inst. C.E., entitled "Some Recent Improvements in Dynamo-Electric Apparatus." The fourth annual meeting of the Dundee Naturalists' Society was held recently. Mr. Grothe, the president, occupied the chair. The secretary read the council's report for the past year, which showed that it had been one of great activity and prosperity. The year began with a membership, including all classes, of 232, but at the date of the report this number had increased to 401, being an increase of 169. The property of the society had also been considerably increased during the year, chiefly by gifts of books and specimens for the society's museum. During the last winter nine original papers had been read by members at the ordinary meetings of the society, treating of geological, biological, physical, and archaeological subjects. During the summer the interest in, and work of, the society was kept alive by a series of very attractive excursions. One excur- sion was a sea-dredging expedition, and opened up for the society a new field for its energies. In order to secure a more ex- haustive and systematic treatment of the various branches of natural science, the society was formed into sections, three in number, viz, : — i. Physical and Chemical ; 2. Geological ; 3. Biological, From this arrangement it is hoped that much good will result. The society is in a very healthy and vigorous condition. The following modification of an experiment of Prof, Tyndall's is described by M, Terquem in the Journal de Physique for October, A trumpet-bell connected by a thick caoutchouc tube with one of Konig's manometric flames, is fixed vertically over a square plate, which is vibrated so as to give two nodal lines as in Tyndall's experiment. If the axis of the bell be placed exactly over the centre of ,the plate, the flame remains quite motionless, and the same if the bell be placed above a nodal line. On the other hand, the flame vibrates when the bell is displaced, however little, and the vibrations become very strong when [the bell is placed above a ventral segment. With two similar trumpet-bells placed over two ventral segments having similar, or contrary movements, the vibrations may be united on a single flame, by means of a Y-tube, a drawing-tube being placed in the passage of one of the vibratory movements. The advantage of this arrangement consists in producing very strong separate vibrations ; moreover, it is possible to give them exactly the same intensity by displacing laterally one of the bells. To obtain absolute motionlessness in the flame the two combined movements must have exactly the same amplitude. To render the flame more brilliant M. Terquem passes the gas through pumice-stone soaked with benzine or the like, and incloses the jet in a tube through which a current of oxygen is sent. A cylinder of mica blackened interiorly, except on the side next the revolving mirror, surrounds the flame. A RECENTLY-PUBLISHED report by the Criminal Administra- tion of France gives some curious statistics with regard to suicides in 1874. There were in that year 5,617 suicides, the highest number ever recorded in the country. Of these 4,435 (79 per cent.) were committed by men, and 1,182 (21 per cent.) by women. The ages of 105 of the suicides are unknown. The 5,512 others are thus divided : — Minors of 16 years, 29 ; 16 to 21 years of age, 193; 21 to 40, 1,477; 4° to 60, 2,214; ^'^^ beyond 60, 1,599. Among the suicides there are enumerated 1,946 celibates (36 per cent.), 2,645 (4^ perxent.) were married, and 881 (16 per cent.) were widowed. Of the number of those forming the last two categories there were 2,259, or nearly two- thirds, who had children. The civil state of 145 individuals could not be ascertained. More than seven-tenths of the suicides were by strangulation (2,472), or by submersion (1,514). The suicides were, as always, more frequent in spring (31 per cent.) and in summer (27 per cent.) than in winter (23 per cent.) and in autumn (19 per cent.). As to the motives, there is no informa- tion about 481 of the suicides ; the others are classed as fol- lows : — Misery and reverses of fortune, 652 ; family troubles, 701 ; love, jealousy, debauchery, misconduct, 815 (of which 572 were brought about by drunken habits) ; physical sufferings, 798 ; various troubles, ^489 ; mental maladies, 1,622 ; suicides of persons guilty of capital crimes, 59. At the meeting of the Eastbourne Natural History Society, of October 19, Mr. Roper read an important paper on "The Addition to the Flora of Eastbourne since 1875." The additions to the Zoological Society's Gardens during the past week include a Tiger i^Felis tigris) from China, presented by Mr. A. Yoxb&sA.ngu^-fS.'M.z.cz.c^&yi.oxikty^Macacuscynofnolgus) from India, presented by Mr. H. W. Henderson ; a Saker Falcon {Falco sacer) from Egypt, presented by Mrs. Arthur Coote ; two Grey Plovers {^Squatarola helvetica), a Ringed Plover ((Egialitis hiaticula), a Dunlin {Tringa cinclus), European, presented by Mr. F. Cresswell; a Calif ornian Quail {Callipepla calif arnica) from California, presented by Mrs. A. H. Jamrach ; a Ring Hals Snake {Sepedon haniachates) from South Africa, presented by Mr. Eustace Pillans ; a Brown Pelican {Pelecanus fuscus) from West Indies, a Cape Zorilla {Icionyx zorilla) from South Africa, purchased ; five Reindeer {Ranifer tarandus) from Lapland, deposited ; a Cape Buffalo {Bubalus caffer) from South Africa, received in exchange. J^ov, 15, 1877] NATURE 55 UNIVERSITY AND EDUCATIONAL INTELLIGENCE Edinburgh. — The Marquis of Hartington has, by a large majority over Mr. Cross, been elected Lord Rector of Edinburgh University. Prussia. — We notice from the last report of the Prussian Minister of Instruction that the present number of instructors in the ten universities amounts to 896, viz., 466 ordinary professors, 7 honorary, 199 extraordinary, and 224 privat-docenten. The philosophical faculties include 400, the medical, 250, the legal, 86, and the theological, 110. The number of instructors varies from 29 at Miinster, to 201 at Berlin. The number of students is about nine times that of the professors, viz., 8,209, and includes 1,080 from other countries than Prussia. According to their faculties they are divided as follows : evangelical-theological, 684, catholic-theological, 289, legal, 2,261, medical, 1,349, and philo- sophical, 3,626. The attendance at the universities during the past summer was Berlin 2,237, Breslau, 1,245, Gottingen, 9^7> Bonn, 897, Halle, 827, Kijnigsberg, 620, GreifswSd, 503, Marburg, 401, Miinster, 315, and Kiel, 241. In the budget submitted to the present Prussian House of Deputies are the following items : — Erection of the German Industrial Museum, 998,000 mk. ; erection of a Polytechnic in Berlin, 8,393,370 mk. ; erection of an Ethnological Museum in Berlin, 1,800,000 mk. \ and for the Berlin University, erection of a Herbarium, 422,000 mk. ; of a Clinic, 1,955,000 mk. ; of a new building for a second Chemical Laboratory, as well as of a Technical and Pharmaceutical Institute, 967,000 mk. Bonn. — On entering upon the duties of rector of the Univer- sity, Prof. Kekule, the distinguished chemist, delivered, on October 18, a brilliant address on the scientific position of che- mistry, and the fundamental principles of this science. He made the following definition of chemistry as distinct from physics and mechanics : — " Chemistry is the science of the statics and dynamics of atoms : physics that of the statics and dynamics of molecules ; while mechanics considers the masses of water con- sisting of a large number of molecules." After rapidly sketching the growth of the present atomic theory, he claimed that the mass of results now obtained showed that chemistry was slowly but surely approaching its goal, the knowledge of the constitu- tion of matter. In opposition to the opinion that theory should be banished from the exact sciences, he regarded it as an actual felt necessity of the human mind to classify the endless series of individual facts from general standpoints — at present of a hypo- thetical nature — and that it was precisely the discussion of these hypotheses which often led to the most valuable discoveries. Vienna. — In Vienna the question is being agitated of separating the natural sciences at the University into a separate faculty, apart from the iphilosophical faculty, as is the case in Strassburg and a few other universities, which have risen superior to the old mediaeval classification. Strassburg. — The imperial authorities have finally decided upon extensive appropriations for the new buildings of the Uni- versity. They will embrace edifices for lecture-rooms, chemical and physical laboratories, and chirurgical and psychiatric clinics. The new observatory will be completed next year, and the botanical gardens are rapidly being laid out. In 1882 the University expects to occupy its new buildings. KoNiGSBERG. — Prof. W. Losscn, of Heidelberg, well known by his researches on hydroxylamine, has accepted a call to the Chair of Chemistry at the University of Konigsberg. Upsala. — The University is attended at present by 1,395 students, of whom the half are included in the philosophical faculty. The corps of teachers embraces sixty-three ordinary and extraordinary professors, and fifty-four privat-docenicn. Of these eighty-two are in the philosophical faculty. St. Petersburg. — The lectures at the St. Petersburg Ladies' High Medical School re-opened this year on October 13. One hundred and eighteen students were admitted, though a far larger number of applicants passed the examination. The number of the students admitted, however, was limited as above because of want of room. A fifth class has now been added, and the students receive, after having finished the studies, the degree of surgeons. SOCIETIES AND ACADEMIES London Linnean Society, November i.— Prof. Allman, F.R.S-. president, in the chair. — Messrs. S. M. Samuel and P. Wyatt Squire were duly elected fellows of the Society. — A communica- tion was read by Dr. G. King on the source of the winged cardamom of Nepal. By Dr. Pereira it had been regarded as the -prodnce of A r/iotnum maximum, Roxb. ; but this is indigenous to Java. Roxburgh named two Indian species, A. aromaticum and A. subulatum, and Dr. King shows that the latter is the so- called winged cardamom of Nepal, its true habitat being the Morung mountains and not the Khasia hills as asserted by Voigt. — There followed a paper by Capt. W. Armit on Australian finches of the genus Pocphila. Mr. Gould had recognised two birds, P. gouldia and P. mirabilis, as good and distinct specific forms, a statement questioned by Mr. Diggles at the Queensl. Phil. Soc, 1876. Capt. Armit having studied the live birds in their native haunts gives his evidence in favour of Mr. Gould as to the just separation of the said Australian finches. — The self-fertilisation of plants formed the subject of an interesting paper by the Rev. G. Henslow, a notice Jof which we shall give elsewhere. — Mr. Ed. J. Miers gave a revision of the Hippidea. " This group of the Anomourous Crustacea, although, by their elongated carapace and antenna; bearing considerable resem- blance to certain of the Corystoidea, to wit the Chilian, Ble- pharipoda spinnimana and Pseudocorystes sicarius, yet the author considers their true affinities to be with the Oxystomatous Brachyura, through the Raninidse. The Plippidea inhabit all the warmer temperate and tropical seas of the globe. Their life history and habits lately have received considerable elucidation at the hands of Mr. S. J. Smith, of Connecticut, in a study of the development of the common species of the eastern shores of the United States. Their limits are restricted northwards by the cold winters. The H. ialpoidea lives gregariously, burrowing in the loose, changing sands near low-water mark. Other species, however, inhabit deep water, such as the Albunea guerinii in the Gulf of Algiers, &c. — Mr. E. M. Holmes laid before the meeting the late Dr. Planbury's collection of cardamoms (from the Pharmaceutical Society) in illus- tration of Dr. King's paper above mentioned; he also drew attention to an undetermined fungus in a sugar cane, which mould had caused the destruction of a plantation in South India. — The Rev. T. H. Sotheby exhibited branches of two remark- able shrubs, Colletia cruciata, Hook., and C. Bictonensis, Lindl., grown in Lady RoUes' garden at Bicton. These South American plants it seems, are not unknown in this country (one Fellow present stating he possessed them now in flower), but the history of their introduction, nevertheless, is a curious one. — Dr. Masters showed an unusual specimen of a grape within a grape, viz., adventitious fruit developed in place of the normal seeds ; he 'also explained the rationale of adventitious tubers producing buds on the root of some examples of Brassica Papa exhibited by him. — Some twigs and flowers of British grown gum trees were shown by Mr. A. O. Walker, among others Penstemon Clevelandii said to have flowered here for the first time. Physical Society, November 3. — Prof. G. C. Foster, pre- sident, in the chair. — The following candidate was elected a member of the Society : Alexander Jesseman. — Prof. McLeod described some experiments he has recently made to determine the exact number of vibrations of tuning forks by means of the apparatus he exhibited to the Society on April 28 last, and which was designed for determining slight variations in the speed of machinery or other analogous purposes. He has studied two sets of forks belonging to the Physical Laboratory at South Kensington, and a new set just received from Konig, and his results exhibit a remarkable concordance, the extreme results in the worst set of observations on a fork of 256 complete vibra- tions only differing by o'oo5 per cent., and in a good set they agreed within o 00078 per cent. Examining the new series from 256 to 512, he found them to give from o'3 to 0'5 of a vibration more than was anticipated, but as this variation 'may be due to a difference between the temperature and that at which they were adjusted, he is waiting to ascertain what this was. He considers also that the manner in which the fork is held has an effect on its vibrations, and he hopes to be able to get some information as to the effect of temperature on elasticity. — Dr. Huggins exhibited some artificial gems recently prepared by M. Feil, the well-known glass manufacturer of Paris, who has succeeded ia cry;s^Uising stones of the corundum class. 56 NATURE \Nov, 15, 1877 Rubies, as well as a topaz and emerald, were exhibited. Dr. Huggins believes that the colour is imparted by small quantities of metallic oxides, and that the mass is mixed with boracic acid and maintained in a fused condition for a considerable period. M. Feil hopes to obtain larger stones by maintaining the heat constant for several weeks consecutively. — Dr. Lodge then read a communication from Professors Ayrton and Perry, of the Imperial College, Japan, in continuation of one read to the Society on May 26 last, on ice as an electrolyte, and since pub- lished in the Philosophical Magazine, The experiments therein described led them to expect a very sudden rise in the specific inductive capacity as the temperature of the ice increased through zero and it became water. Recent results have shown that, though rapid, this increase is not as great as they anticipated, and, whereas at - 12° C. the capacity is o'oo2 microfarads, at + 5° C. it is o'l 185 microfarads, and after this temperature the in- crease was so rapid as to render exact readings difficult. Referring to Prof. Clerk Maxwell's theory in which he compares electro- magnetic disturbances with light vibrations, they point out that he exclusively regards a conducting medium. But they showed in a former paper that no dielectric can be considered non-conduct- ing, hence they conclude that the measured specific inductive capacity can never be even approximately equal to the square of the index of refraction. Prof. Foster mentioned that he re- cently had occasion to collect as many results as possible on specific inductive capacity and refractive index, and he found that, where these figures were low, the agreement with the law was fairly close, but with greater values the inductive capacity and the square of the refractive index separate very rapidly. — Prof. Guthrie described a simple means for showing the inter- ference between two plane waves by means of two long cords vibrating side by side. If a vibration of considerable amplitude be imparted to them, and the plane in which they travel be care- fully examined, two faint black lines will be seen, which cross and recross each other more rapidly as the cords are less and less in unison, and with perfect unison remain stationary. Royal Microscopical Society, November 7. — Mr. H. C. Sorby, president, in the chair. — A paper was read by Mr. Thos. Palmer on the study of evergreens by means of the micro- spectroscope, in which he described the results of his examination of solutions of the colouring matters, oils, &c. , from the leaves in various stages of growth. The paper was illustrated by drawings arid by the exhibition under the micro-spectroscope of some of the solutions referred to. — A paper by Mr. F. A. Bedwell on the building apparatus of Melicerta riiigens, was read by the secretary. It minutely described the structure and functions of those organs, and was an important addition to the number of contributions to the history of this beautiful rotifer. The paper was illustrated by drawings, some of which were enlarged upon the black board by Mr. Charles Stewart. — A paper was taken as read on the lachrymal gland of the turtle, by Mr. Charles Stewart, Paris Academy of Sciences, November 5. — M. Peligot in the chair. — The following papers were read : — On some applications of elliptic functions (continued), by M. Hermite.— i?if«/w/ of a history of matter (third article), by M. Chevreul. This comprises from the thirteenth to the seventeenth century. — On the hydroge- nation ot benzine and aromatic compounds, by M. Berthelot. The experiments show that the action (surficiently intense and pro- longed) of hydriodic acid brings all these carburets to the com- position of carburets absolutely saturated, such as hydride of hexylene, C1.2H14, volatile about 69°. — Reply to a recent note of M. de Parville, "On the semi-diurnal variation of the baro- meter," by M. Faye. — The echidna of New Guinea, by M. Gervais. This animal is very different from the echidna of Australia. Inter alia, it is larger and has darker hair; the claws (which are strong and adapted for digging) number three on the fore as on the hind feet ; and the (black) muzzle is much longer than in E. aculeata, and sensibly arched ; the tongue is also much longer and very slender, and the homy papillae are differently arranged ; the number of vertebras and ribs is dif- ferent, &c. M. Gervais regards the animal as belonging to a separate genus, termed Acanthoglossus. — On a project of an inter- oceanic canal; studies of the international commission of the Isthmus of Darien, by M. de Lesseps. This relates to a report of recent scientific exploration by Lieut. Wyse (of the French Navy), The project comprises a tunnel of about 17 kilometres, the remainder of the length being ^bout $5 kilometres. The total cost is estimated at 600,000,000 francs. — Stellar systems formed of stars associated in a common and rapid proper motion, by M. Flammarion. — On the order (or class) of a plane algebraic curve, of which each point (or each tangent) depends on a corre- sponding point of another plane curve and on the tangent at that point, by M. Fouret. — Applications of a mode of plane repre- sentation of classes of ruled surfaces, by M. Mannheim. — On the liquefaction of acetylene, by M. Cailletet. The gas was com- pressed by means of a hydraulic pump through mercury, in an apparatus of special form. Acetylene is liquefied, e.g., at + l° under 48 atm., at 18° under 83 atm., at 37° under 103 atm. The liquid is colourless and extremely mobile ; it seems very refringent, and is lighter than water, in which it can be largely dissolved. It dissolves paraffin and fatty matters. Hydride of ethylene was liquefied in the apparatus at a slightly higher pressure than that of acetylene. The tensions of these two carburets and ethylene are but little different about zero. Reaction of chlorhydric acid on two isomeric butylenes and on olefines in general, by M. Le Bel. The ethylenic carburets combine with cold chlorhydric acid ; on the contrary, the hydrocarbons CHj = CHR and pro- bably those with the formula CHR = CHR' are not attacked, — On the alteration of eggs produced by mould from without, by MM. Bechamp and Eustache. Hen's eggs may remain long in a medium filled with infusoria without these organisms pene- trating. The shell and its lining membrane can be traversed by mucedineoe, which develop abundantly on the inner face of the latter. The yolk-membrane, however, is impenetrable by muce- dinese or any other microzoa or microphytes. The mediate relations of mucedineae with the yolk produce a true fer- mentation apart from any organic ferment except micro- zymas. The acidification of the white is due exclusively to the mycelium of the mould. The production of bacteria in the yolk is due to development of the normal microzymas of the yolk. — On a new function of the genital glands of sea-urchins, by M. Giard. During part of the year these glands play the part both of excretory organs and of deutoplasntiigenic organs. This fact presents a new point of relation between echinoderms and annelids, and even arthropods. — Causes which determine the liberation of agile bodies (zoospores, antherozoids) in the lower plants, by M. Cornu. The exit is not the result simply of a physical phenomenon of endosmose, but is at least partly due to the activity of the corpuscles themselves. This activity re- quires a sufficient temperature, or a certain quantity of oxygen (furnished directly or by oxidation of the green parts), for its exercise. — Meteorological observations made in a balloon, by M. Terrier. This ascent was made on October 18, at 3.30 P,M,, from Paris. It is affirmed that the temperature of the atmo- spheric layers at sunset decreases uniformly with increase of height (the decrease was i° per 100 metres). The lower winds are less stable than the upper, and it is necessary to interpret the latter for weather prognostication. The aerial currents of small height and velocity are influenced and notably deflected by the inequalities of the ground. CONTENTS Page Brehm's Thierlkben 41 Our Book Shblf : — Loewy's "Heat" 43 Smith's " Ferns, British and Foreign. The History, Organo- graphy, Classification, and Enumeration of the Species of Garden Ferns, with a Treatise on their Cultivation " 43 Letters to the Editor : — The Radiometer and its Lessons — Prof G. Carey Foster, F.R.S. ; William Ckookes, F.R S. ; Alfred R. Wallace 43 Experiment on Fluid Films.— Sedley Taylor 44 Expected High Tides.— B. G Jenkins 45 The Towering of Wounded Birds. — Charles Dixon 45 Cruelty to Animals' Act and Physiological Teaching. — Frank W. Young 45 Smell and Hearing in Moths — J. C . 45 Bees Killed by Tritoma. — Alfred R. Wallace 45 Lecture Experiment. — W. A. Shen stone 45 Fownes' " Manual of Chemistry." — The Reviewer 46 Our Astronomical Column : — The Transit of Mercury, May 6, 1878 46 Nova Cygni, 1876 46 Comet 1873, IV. 46 Minor Planets 46 The Royal Dublin Society 46 On the Eocene Flora of Bournemouth. By J. S Gardner . . 47 The Telephone 43 African Exploration 49 Modern Torpedo Warfare (With Illustrations)', 50 Notes ;...... . . 52 University and Educational Intelligenck 55 SoCIBTIKS AND ACADfCMISS i • • • t - 55 NA TURE 57 THURSDAY, NOVEMBER 22, 1877 DANISH GREENLAND Danish Greenland ; its People audits Products. By Dr. Henry Rink. Edited by Dr. Robert Brown, F.L S. With Illustrations by the Eskimo and a Map. (London : Henry S. King and Co., 1877.) THERE is a strange fascination about Greenland, which may be partly owing to the mystery that shrouds its early history, — partly to its being an almost Arctic country, the scanty population of which seems to furnish an example of a nation in the enjoyment of a very primitive culture ; and partly because it seems very prob- able that it was from it started the voyagers who were the first discoverers of what is now called America. Our knowledge of the early history of Greenland is limited to what we can gather from the Icelandic sagas or popular tales, and from these we find that about the year 986 an Icelander called Erik the Red, who had been outlawed, sailed to the west to look for some land which had some years previously been sighted by Gunbjdrn, the son of Ulf Kraku, another Icelander who had once been driven far westward by a very fierce storm. Erik found the land, made a two winters' stay thereon, giving names to many places, and returning to Iceland called this new country Greenland, because, said he, people would sooner be induced to go thither in case it had a good name. This first colonisation of Greenland seems at the time to have been fairly successful, and several ruins are still to be found which throw a light on the habits of these seafaring people. The present Eskimo station, Igaliko, situated on an isthmus between two fjords, is thought to have been the ancient residence of Erik. One of Erik's friends, named Herjulf, had a son called Bjarni, a promising youth, and very fond of travelling abroad. One year he would spend in Iceland, another with his father in Greenland. Wishing, however, to spend one Yule-tide with his father, he set sail for Greenland, where his father was, with a crew who had never been in the Greenland Ocean before, and the consequence seems to have been that he found himself after many days near a country covered with wood, which was certainly not Greenland, and turning his back upon it to hasten to find his parent, he succeeded in landing at the very spot where his father lived. It is probable that during this voyage he had discovered the tract of country stretching from Connecticut to Newfoundland. The news of Bj ami's venturesome voyage spread to Iceland and to Norway, and Leif, the son of Erik the Red, bought his ship, and set sail for the new country, on which they landed, and which, from finding on it a species of " fox-grapes," they called Vinland. Returning the next year to Greenland, it was no wonder that Vinland was all the talk, and Thorvald, about 1002, went to settle there and finally had a battle with the natives, in which he was killed. This Vinland was probably the present Massa- chusetts. Half a century later tidings from the Green- lard colonies suddenly became rare, but in 1126 the then pope sent them a bishop, the ruins of whose church are still pointed out, and about 1261 the Greenlanders became subjects of Norway. From this date to Vol.. xvii. — No. 431 1450 tidings of the colonists, stories of their doings, and records of their misfortunes, came less and less frequently to Europe. The very sailing route passed into oblivion, and the country was only again re- dis- covered in 1585 by John Davis, whose name will be for ever remembered in connection with the Straits also discovered by him. Another century-and-a-half passed away before the present European stations in Greenland were founded by the well-known Danish missionary, Hans Egede, who in 1 72 1 landed on an island at the mouth of the Godthaab-fjord and founded a regular colony. From then until now, with many a vicissitude ; an epidemic of small-pox in 1734, a total interruption with Den- mark (1807-18 14) on account of the war ; the colonies have struggled on. The trade was for some part of the former century made a private monopoly, but in order to keep up the commerce, the government was finally obliged to take it in hand, and since 1774 it has continued to be a royal monopoly. Following the steps of the extending trade, the missionary institutions have gradually incorporated the whole population into Christian communities. Dr. Rink's book tells us in a very succinct though most interesting manner, of the results of the European transactions thus carried on in Greenland, for now over a century, and he describes the present state, and hints at the future prospects of the population. More than this, he gives us in well-written chapters, an account of the configuration and general physical features of this almost frozen up island, he tells of its " inland ice," and of the origin of the " floating icebergs." We read of the tempera- ture, prevailing winds, the wonderful changeableness of its weather, and we find here a rhume of all that is known about its lakes and streams, its mysterious fjords, and of its great fields of drifting ice. Nor is the natural history of the country overlooked, for we have a chapter on its geological and mineral products. Of these latter cyolite appears to be the only one that has become a regular article of trade, about 10,000 tons thereof being exported each year. There are also chapters on its plants and animals, with special ones on the capture of whales and seals, and on the Greenland fisheries. From an Eskimo point of view the commercial import- ance of the seal and whale fisheries is very great. The flesh and blubber of these animals not only supply the Greenlander with nutritious food, but also provide him with heat and light. The sealskins too afford material for clothes, boats, and tents, and whaleskin called " matak," yields a favourite article of diet It may give some idea of the vast numbers of these animals killed yearly to summarise the average annual catch as follows : Of Phoca foittda, 51,000 ; of P. vttulina, 2,000 ; of P. groenlandica, 33,000 ; of P. barbata, 1,000 ; of Cystophora cristata, 3,000 ; and of narwhals, white whales, and walruses nearly 1,000. The right whale has nearly dis- appeared and the mean annual catch of the "humpback" whale is scarcely over two. The most important fisheries in addition appear to be those of the cod fish, the halibut, and the capelin. Perhaps there was not much to be said about the man- ners and customs of the people in the olden time ; the change in religion seems to have very early modified the social condition of the people, and this portion of Dr. 58 NATURE \N0V. 22, 1877 Rink's book is the one that satisfied our curiosity the least. The sketches of Greenland life by natives, as translated from the " Greenland Journal," are interesting, but they tell us of very little except marvellous escapes from snowstorms and icebergs. The great endurance of suffering, as detailed in some of these stories, demon- strates that heroes can be found even in Greenland ; the sublime spirit of martyrdom seems to breathe in the account of the " Kayakers cast ashore in a snowstorm." Scattered through this volume are some sixteen plates, representing Greenland ways of life. These are exact copies of partially coloured drawings executed by natives entirely after their own ideas. The greater number are the work of a seal-hunter living in Kangek, who, falling sick, could not leave his bed. With the drawing which forms plate 16, he wrote to say that increasing illness pre- vented him from doing more, and he ended the letter with " from exhaustion I must cut my letter short, this too will be my future fate," and shortly after he died. E. P. W. OUR BOOK SHELF A Sketch of the Geology of Leicestershire and Rutland' By W. J. Harrison. (Shtffield : W. White.) This is a creditable compendium of what is known regarding the geology of the two countries of which it treats. It was originally prepared by its author for White's " History and Gazetteer of the Counties," and has been reprinted in a separate form. It can be had embellished with twelve photographs of various parts of the crystalline nucleus of Leicestershire. These are not particularly successful. Mr. Harrison has done well to put the best of them as a frontispiece. It represents the " coarse ashy slates "- of Charnwood Forest. As a local guide this book may no doubt be useful ; fuller informa- mation can be found in the works which Mr. Harrison cites, and especially in the maps and memoirs of the Geological Survey. LETTERS TO THE EDITOR [The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts. No notice is taken of anonymous communuations. The Editor urgently requests correspondents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of com- munications containing interesting and novel facts.'] Expected High Tides If I may judge from the note published in your issue of November 8 (p. 38), and Mr. Jenkins' letter in the last number of Nature (p. 45), it would appear that the general public are unaware of publications which contain information respecting high tides. The Admiralty tide tables contain the time and height of every tide in the year for twenty-four of the principal ports of the United Kirgdom. There are also numerous other tide tables published, which give the heights as well as the times of high water. Amongst these may be mentioned Holden's Liver- pool table?, which contain, besides Liverpool, eight other ports (London irc'uded), and at Liverpool are held in higher esiima- tion than the Admiralty tables, inasmuch as Holden's predictions take into account the effect of the diurnal inequality at Liver- pool, which heretofore has been neglected in the Admiralty tables. There are also published at South Shielf^s, Ainsley's, and at Hartlepool, Pearson's tables, and at Bristol, Ariowsmith's tables (formerly Bunt's), which have deservedly a high reputa- tation for Bristol and the Bristol Channel ports generally. Any one who will select from these publications the highest perigean spring tides about the time of the equinoxes, and will send them to the papers, can apparently earn for himself the credit of "predicting" high tides. The increased range of tide in the Thames of about twenty inches during the last twenty years, is undoubtedly due, among other improvements, to the construction of the embankments, the increased water-way at the bridges at Westminster, and notably at Blackfriars, the improved line of wharfage continually being carried out, and the removal from the Pool of the colliers, which at low water acted as a dam, and prevented the improvement of the bed of the river. An overflow in the Thames at above-average spring-tides is now a matter of meteorological circumstances only. It has been observed, I believe, without exception that the overflows have been ciused by a strong northerly wind ; the most disastr^jus overflows, however, have followed a strong south-west wind, changing suddenly to a stiff norlh-west wind. The reason is obvious. An increased amount of tidal water with a south west wind and generally low barometer, is carried from the Atlantic to the northern parts of the North Sea, a sudden change in the wind to north-west brings the whole of this water to the south- ward, with probably litde or no disastrous effects until it reaches the mouth of the Thames, where it meets with the tidal water of the English Channel brought through the Straits of Dover. It then rushes up the Thames, and an additional height is given to the water, amounting sometimes to as much as four feet or more if there is much flood water meeting it, and an overflow is the consequence. I find the effect of a south-west wind on the tide in the Thames, as traced on a self-registering tide-gauge I have placed at Greenwich pier, is to depress the water considerably. The high water of Monday morning succeeding the he?,vy gale of Sunday, November il, was nearly two feet below the pre- dicted height, the extreme pressure of wind, as registered at the Royal Observatory, being 31 lbs. on the square foot. In the middle of October the effect of a south-west gale was still greater, probably owing to its longer continuance, although the registered pressure did not exceed 23 lbs. No overflow need therefore be feared from a continued south-west gale. Mr. Jenkins is perhaps unaware that Mr. Saxby has "predicted " high tides for many years, and that on one occasion, I believe in September or October, 1869, the Astronomer- Royal wrote reassuring the public that there was nothing extraordinary in the then forthcoming spring tides to occasion unnecessary alarm. If Mr. Saxby has discovered some law by which he can foretell the direction and force of the wind he will undoubtedly confer an inestimable boon by its publication, but from the following extract from the Times of November 5 he does not appear to claim any such knowledge : — "Capt. Saxby further states : ' If the wind should blow from a northerly quarter on either the 7th of November or 22nd of December next, very full tides miy be reasonably expected.' " The spring tides about December 22 are slightly below average, and as no overflow has yet occurred with below-average spring tides, but little apprehension need be felt respecting them. With respect to the actions of Venus and Jupiter ; although theoretically they cause tides, the Values have hitherto not been evaluated, being almost insensible. The high tide of October 26th was entirely due to the northerly wind ; the effect due to the maximum northern declination of the moon is very small in the Thames, and is more than counter- balanced by its effect in decreasing the value of the lunar semi- diurnal tide. Mr. Jenkins' statement respecting two great tides revolving through the year exactly six-and-a-half synodic months apart is merely on account of thirteen semilunations being very nearly equal to seven anomalistic months, and therefore the lunar perigee has again the same phase with respect to new or full moon, I may mention that ninety-nine semilunations exceed four years by about eighteen hours only, and also fifty-three anomalistic months by less than thirty-three hours. So that after a cycle of four years the perigean spring-tides fall very nearly on the S'me days of the year. This of course fails to take into account the variations due to' the moon's declination. The following table of the heights of the above-average spring- tides for London for next year may be useful not only to river- side owners and dwellers, but also to marine naturalists, who will on these days have unusually favourable opportunities at low- water of engaging in their pursuits. If at such limes the baro- meter should be high the low-water level will be still further depressed. It will also act as a guide to tourists wishing to avail themselves of the best chances of witnessing the bore in rivers, Nov. 2 2, 1877] NATURE 59 notably on the Severn, wbicb, according to Mr. Alfred Tyler, F.G. S., is seen to best advantage with a rising sun from Stone- bench Inn, about three miles below Gloucester. Height He; ght Height 1878. above I 378. above I 878. above average- average. average ft. va. ft. in. ft. in. Jan. 20 p.m. 0 4 April 17 a.m. 0 8 Sept. I a.m. I 3 ,, 21 a.m. 0 7 j> ,, p.m. 0 II 1) „ p.m. 0 II ,, ,, p.m. 0 9 >j 18 a,m. I I )> 2 a.m. 0 7 ,, 22 a.m. 0 10 »» ,, p.m. I 3 ,, ,, p.m. 0 11 j> 19 a.m. I 3 >> 26 a.m. 0 I „ 23 a.m. 0 10 »> ,, p.m. I 0 )) ,, p.m. 0 7 ,, ,, p.m. 0 7 >> 20 a.m. 0 9 >) 27 a.m. I 0 ,, 24 a.m. 0 4 >) ,, p.m. 0 5 >) „ p.m. I 4 0 I )> 28 a.\Ti. I 7 >> ^ 1 a. ID. Feb. 18 a.m. 0 5 j> ,, P-m. I 8 ,, ,, p.m. 0 II May 16 a.m. 0 I »> 29 a.m. I 7 „ 19 a.m. 4 >» „ p.m. 0 2 )> „ p.m. I 4 ,, ,, p.m. 5 )> 17 a.m 0 3 91 30 a.m. I I ,, 20 a.m. 6 )> „ p.m. 0 3 >> ,, p.m. 0 9 „ ,, pm. 6 >> 18 a.m. 0 3 Oct. I a.m. 0 4 „ 21 a.m. 5 >> „ p.m. 0 2 ,, ,, p.m. 3 >) 25 a.m. 0 2 ,, 22 a.m. 0 10 July 31pm. 0 3 j» ,, p.m. 0 6 ,, „ p.m. 0 4 Aug. I a.m. 0 5 >> 26 a.m.j 0 10 ?> ,, p.m. 0 7 )> ,, p.m. I 0 Mar. 18 p.m. 0 3 )) 2 a.m. 0 9 )> 27 a.m. I 2 „ 19 a.m. 0 9 )> ,, p.m. 0 9 >> ,, p.m. I 4 „ ,, p.m. 3 )> 3 a.m. 0 9 >i 28 a.m. I 2 ,, 20 a.m. 6 >> ,,p.m. 0 6 )) ,, p.m. 0 II ,, ,, p.m. 9 >> 4 a.m. 0 3 )) 29 a.m. 0 8 ,, 21 a.m. 9 >> M P-m. 0 4 „ „ p.m. 7 1) 28 pm. 0 I ,, 22 a.m. 5 >> 29 a.m. 0 6 Nov 24 a.m. 0 I ,, „ p.m I >> „ p.m. 0 » „ p.m. 0 3 „ 23 a.m. 0 8 >> 30 a.m. 3 >> 25 a.m. 0 4 ,, ,, p.m. 0 I >> „ p.m. 5 >> ,, p.m. 0 4 >> 31 a.m. 5 >> 26 a.m 0 5 April 16 p.m. 0 4 jj ,, p.m. 5 )> „ p.m. 0 3 From the above table it appears that the highest tides of the year will occur on March 20-21 and September 28. The heights will be found probably to exceed those of the Admiralty Tables, as I have employed larger factors in the necessary corrections to the semi-menstrual inequality. As a London tide table appears to be a desideratum, I have been induced to publish one for next year, in which the "dan- ger " tides will be distinguished in a new, bold, and unmistak- able manner. Edward Roberts 3, Verulam Buildings, Gray's Inn, November 17 Rainfall in the Temperate Zone in Connection with the Sun-spot Cycle This month's number of the Nineteenth Century contains an article on the connection of rainfall with the eleven years' cycle of sun-spots. It takes a carefully-selected area in which such a coincidence, if it existed, would be well marked. The great tract of water spreading southwards from Asia to the southern pole affords an arena for the undisturbed play of solar activity. It may readily be understood that any excess of solar energy has a more direct and uniform influence upon the rainfall gathered from this vast aqueous expanse, than it would have upon smaller areas of water interminjiled with tracts of land, and cut off from each other by ranges of mountains, as in the European and American continents. Other reasons exist which would render solar influence a more directly potent factor in the rainfall gathered from the Indian Ocean than in that of the temperate zone. Without doing more than alluding to the fact that sun- spot activity is confined to a belt of considerable thickness on either side of the sun's equator, there are several well-ascertained causes which would render an excess of solar activity more directly felt in the equatorial regions of our earth than in those nearer the poles. While, therefore, I believe that the coinci- dence of a rain cycle and of a cycle of wind disturbances with the eleven years' cycle of sun-spots, has now been established as regards the Indian Ocean and the Madras rainfall, I am anxious to guard against the conclusion beinij pushed too far. The article in the Nineteenth Century proves much, but it would be a misfortune at this still early stage of the inquiry, if wider inductions were drawn from it than are justified by the evidence which it brings forward. . It seems right, therefore, to state that so far as my investiga- tion of the rain returns of the temperate zone yet enables me to form an opinion, the cyclic coincidence of the rainfall with the eleven years' cycle of sun-spots, seems to shade off in extra- tropical regions until it ceases to exist at all. This opinion is ^ased upon an examination of the returns of between one and two hundred stations in different parts of the world, but only with regard to one-third of them is the evidence sufficiently complete as to raise more than a presumption either for or against the exist- ence of a cycle. Further, I have not yet been able, except in comparatively small groups of stations, to examine the monthly returns or to separate the winter from the summer rainfall. This separation forms one of the first essentials to arriving a' a final opinion on the question. Subject to these remarks, I beg to state the facts with regard to the rainfall of the northern extra- tropical zone in India, Europe, and America. It is chiefly with the first and last-named countries that the present contribution will deal. In my " Cycle of Drought and Famine," printed in India on the commencement of the late dearth, I mentioned that the rainfall which, in periods of minimum sun-spots, passes uncondensed over the Southern Presidency, might possibly "fill in the temperate zone. The excessive rain, if it takes place anywhere, will probably be found in India between the 22nd and 32nd degree of north lati- tude, to the south of the great Himalayan partition wall." Tne conjecture was based upon the configuration of the Indian con- tinent, which, in its lower and middle regions, receives the rainfall gathered from a vast ocean, and is provided with a barrier at the upper end to arrest the rain-clouds on their further progress northward. Prof. Archibald's examination of the rainfall in Northern India now throws a clear light on this side of the question. He has published in the leading Calcutta paper, the Englishmaft, a series of carefully-compiled returns from stations within the ten degrees of latitude above mentioned. He shows that the rainfall of the sub-tropical region, from 22° to, say, 30°, is in some respects (but only in some respects) complementary to the rainfall of Southern India, and in a recent letter to me he thus summarises his conclusions : — First, the winter-rainfall of Northern India varies inversely with the sun-spots in a well- marked manner at all the stations. Second, the summer rain- fall varies directly with the sun-spots, in a manner well marked in the north-western provinces, by no means marked in the lower provinces of Bengal, but sufficiently well marked when the returns of the several stations are combined. Let us examine the meaning of these facts. The returns from Madras and Bombay (lately published in Nature and elsewhere) prove that when the summer monsoon strikes Southern India, its aqueous burden varies directly with the sun-spots. Prof. Archibald's returns now show that the ramfall brought by the summer monsoon to Northern India also varies directly with the sun-spots. But they prove more than this. They show that the rain-clouds which, in years of minimum sun-spots pass over India without dropping their watery burden, are found, on their being stopped by the Himalayan partition wall, to be charged with a more than average surplus (so to speak) of moisture. In Northern India, therefore, the summer monsoon, on its passage up, brings, as in Southern India, a rainfall varying directly with sun-spot activity ; but the winter rainfall, i.e., the immediate rebound of the rain-clouds from the Himalayan barrier, varies inversely with sun-spot activity. I say the immediate rebound, for it must not be forgotten that the north-eastern monsoon (October to December), when it strikes Madras in its full develop- ment, after collecting its aqueous freight from the Bay of Bengal, follows the same law as the summer monsoon (May to Sep- tember), and varies directly with the sun-spots. Passing from the sub-tropical region of Northern India (22° to 32° lat.) to the temperate zone, we find the evidence of a cycle either very faint or altogether wanting. With regard to Europe, I am not yet prepared to offer any new facts. The existing evidence only amounts to this : (i) Mr. Baxendell, from observa- tions for a comparatively short period but very carefully recorded and scrutinised, came to the conclusion that even at an English station, notwithstanding the manifold disturbing influences incident to our insular meteorology, changes take place in the rainfall as well as in the temperature and barometric pressure, 6o NATURE {Nov. 22, 1877 which correspond closely in their maxima and minima periods with those of sun-spots. {2) A more comprehensive survey of the European rainfall has so far failed to establish this correspondence. Dr. Jelinek's examination of fourteen sta- tions, from 1833 to 1869, showed that the coincidence held good in fifty-two cases, bat failed in forty-two. While frankly accepting this as evidence against a real coinci- dence, it should be remembered that a general law such as a common periodicity in sun-spot activity and terrestrial rainfall will be subjected to, and sometimes overruled by, the local surroundings of individual stations. (3) On the other side, Gustav Wex, from the recorded depths of ttie El^ie, Rhine, Oder, Danube, and Vistula, for six sun-spot cycles (1800-1867), found that the maximum amount of water occurred during periods of maximum sun-spots, while the minimum levels were reached in the periods of minimum sun-spots. The evidence, as regards Europe, is, therefore, conflicting ; and it is safer for the present to reckon it as against a well-marked common periodicity. I hope at no distant date to submit the results of a new and more exhaustive examination of the European rain- register?. I now proceed to the North American rainfall. Here, as in Europe, the question is complicated not merely by disturbing me- teorological influences, such as the Gulf Stream, but by the uncer- tain value of the rain-returns. These are causes which even at a carefully supervised station render it difficult to estimate the number of inches yielded by long-continued or very violent snow- storms. At badly supervised stations, or in the case of private gauges where the supervision is apt to be of a still more hap- hazard character, these difficulties often suffice to render the returns quite worthless. Yet it is the latter class of records on which we have chiefly to depend in an attempt to deal with the American rainfall during a long series of years. Nowhere does meteorology now receive more careful and scientific study than in the Western Continent, but in many of the most valuable series the element of time is still necessarily wanting. The tvidence hitherto received from America has, on the whole, been favourable to the existence of a common periodicity. Mr. Dawson, Geologist to the British North American Boundary Commission, found a correspondence, although by no means an absolute one, between the fluctuations of the great lakes and the sun-spot periods. This question has been lately revived and interpreted afresh by a distinguished meteorological observer in Northern India. Prof. Brocklesby's contributions to the Ame- rican Journal of Science also point to a connection between variations in the sun-spot area and annual rainfall. It was with a knowledge of these statements that I undertook a systematic inquiry into the American rain-returns. I ought at once to say that the result of that inquiry altogether fails to establish the existence of a common cycle, so far as concerns the temperate zone. I divided the American stations into four groups. The first group consisted of eleven stations in east coast or Atlantic States, lyinjj between 40° and 45° N. latitude. The second group consisted of seven stations in Inland States, from 38° to 48°. The third group was intended to consist of s'ations in the West Coast or Pacific States, but I have obtained the returns (and those for a period altogether too brief) for only a single West Coast Station, San Francisco. I give them, how- ever, for what they are worth. The fourth group consists of three coast-stations in the Southern States, between 30° and 33°; or just above the sub-tropical region with which Mr. Archibald's returns for the Bengal stations deal. The results of the examination of the four American groups may be summarised thus : (i) Taken as a whole, the returns from the twenty-two stations do not exhibit any common periodicity between the rainfall and the sun-spots ; nor do they disclose an eleven year's cycle corresponding to the one which I have shown to exist in the rainfall (at Madras and elsewhere) gathered from the Indian Ocean. (2) That as regards the three northern groups, stretching across the continent from 38* to 48' N, lat., the rainfall, so far as any symptoms of periodicity can be detected at all, tends to vary inversely with the sun-spois ; but that it is impossible to discover any real periodicity whatever. (3) On the other hand, that as regards the southern group, between 30° and 33°, there are symptoms of a periodicity tending to coinciae with the sun-spot variations ; but that these symptoms are not suffi- ciently uniform in the small number of southern stations which I have examined, to justify any conclusion. The calculations on which these results are based would occupy many pages, but their general line may be indicated in a few sentences. Thus the mean rainfall at the twenty-two stations during the years of maximum sun-spots for which the records have been obtained, was 37J inches, while during the years of minimum sun-spots it was 39. The years of maximum sun-spots, together with the years immediately preceding, had a mean fall at the twenty-two stations ot 40*2 inches ; wtiile the minimum years of sun-spots, taken together with the years immediately preceding, had an almost exactly equal rainfall of 40'i inches. In the northernmost grouo of eleven /Vtlantic stations the mean rainfall of the years of maximum sun-spots was 39 inches, agaiist an average of 41 inches in years of minimam suti-spots ; in the second group of seven inland stations (38" to 48") the mean rain- fall of the years of maximum sun-spots was precisely equal to that of years of minimam sun-spots, being 33I inches in both ; in the third group, San Francisco, the mean rainfall years of maximum sun-spots was 21 inches against 23^ inches in minimum years ; in the fourth group of three southern stations (30° to 33°) the returns for the minimum and maximum years are broken ; but taking these years and the preceding ones together, the mean rainfa'l of the years of maximum sun-spots with the years immediately preceding was 51 inches, against 48 J inches in the years of minimum sun-spots and immediately preceding ones. The returns have also been examined by another method. I have shown elsewhere that the rainfall at Midras, and other stations around the Indian Ocean, follows a well-marked cycle of eleven years, with a miximum, minimum, and intermediate period, corresponding with the maximum, minimam, and inter- mediate period of sun-spots. The American stations not only fail to show such a correspondence, bat as regards the three northern groups so far as any symptoms of periodicity exist, they point in the opposite direction. The fourth or southern group of stations, on the other hand, so far as they disclose a periodicity, tend to coincide with the periodical variations in the sun-spots. The following table will show this. The Madras rainfall in the tropics discloses a cycle closely corresponding with the eleven cycle of sun-spots ; speaking generally, the American rainfall in the temperate zone discloses no such cycle ; but the southern stations begin to furnish symptoms of such a cycle. Table of Madras and American Rainfall Compared with the Eleven Years' Cycle of Sun-spots 13 ^S Rainfall and sun-spots shown in 1j "^ p*^ the mitiimura, intermediate, and maximum groups of the eleven 5 - ?^ Remarks. years' cycle. ■pi §0-0 E = § 'is'' 2 c G ^1" S ^s s Eleven years' cjcle of sun-spots (from Wolf's lists) 12 6 43 '5 768 Eleven years' cycle of rainfall at Inches. Inches. Inches. Common Madras 4a"3 4;o 53 '5 I Period- Eleven years' cycle of rainfall ; ( icity well- mean of three stations around marked. the Indian Ocean 43 '4 48-1 52"2 North American Rain/all. Mean of eleven stations in East Coast States, 40° to 45° N. lat. ... 40 'a 41-6 40" I ] No Mean of seven stations in Inland States, 38' to 48° N. lat 35'3 35-8 34 '6 ( commo.T 1 Period- Saa francisco ; West Coast Sta- tion, 38° N. lat. ... _ 22 9 19 9 223 J icity. Mean of three stations in Southern States, 30° to 33° N. lat 470 Sf2 49 1 Symptoms of common Periodicity. Note. — The sun-spot figures represent the relative numbers, reduced from Wolf. I he rainfall is expressed in inches. The San Francisco returns deal with only tweuty-one years, or not. quite two complete cycles; much too short a period for any definite conclusion. The records of the twenty-two American stations extend over brief periods compared with the Madras returns. Several of them disclose breaks or gaps ; few of them have been kept with the minute care bestowed by the professional astronomical staff^ on the rain gauge at the Madras Observatory, and the value of most of the eighteen northern ones is rendered in some degree uncertain by snow-storms. It is probable, moreover, that better and much more complete returns are available to American meteorologists than I possess for the twenty-two stations which l^OV. 21, 1877] NATURE 61 I have examined. They will come to the criticism oi my reiults with fuller materials than are available to me here, but so far as these materials enable me to form an opinion, the result is against the existence of a common periodicity in the sun-spots and in the American rainfall within the temperate zone. Allanton, Lanarkshire, November 4 W. W. Hunter Contribution to the Sun-spot Theory of Rainfall The Lucknow Meteorological Observatory has been estab- lished since 1868, and regular observations have been recorded since that year under my superintendence. In Nature of December 12, 1872, Mr. Lockyer published a notice of Mr. Meldrum's discovery of the coincidence between the maximum and minimum sun-spot periods, and the maximum and minimum rainfall in certain places. After reading it I examined the annual rainfall at Lucknow from 1868 to 1872, and found that there was reason to believe that the rainfall at Lucknow followed the same cycle as that of the sun-spots. The figures were : — 1868 27-6 inches. 1869 4i"9 .. 1870 646 ,, 1871 65-0 „ 1872 4i'4 .. The equal amount of rainfall (41 inches) on both sides of the maximum fall of 1870 and 1871 was very striking, and as there was a rise in the rainfall from 1868 to 1870-71, and after that a decrease, and having just read Meldrum's disc jvery, I conjectured that the annual rainfall would continue to decrease till it reached its minimum. In my annual abstract, which I submitted to Government in April, 1873, and on the slender evidence of five year's rainfall, I ventured to state that if Meldrum's law be true, we had in Lucknow lately passed the period of maximum rainfall, and were descending towards a minimum, S3 that during 1877, 1878, and 1879 there would be a scarcity of rain, and in one of those years the minimum rainfall of the cycle would occur. I am now able to give the annual rainfall of almost a complete cycle, and the figures will speak for themselves : — 1867 was a sun-spot minimum period. 1868 27-6 1869 419 1870 64-6 1871 65-0 1872 * 4r4 1^73 35-1 ) 1874 5i"4 1875 43'5 1876 23-6 1877 ' "7 (Up to date October 22). This is October 22, 1877, and the total fall up to date has been orly 117 inches, about a third of which fell in the months of January, February, and March. The fall during the rainy season of 1877 has been so small that great fear of a famine has been felt. I considered Meldrum's discovery so important that at the end of my annual abstract of meteorological observations for 1872, I inserted a long abstract of Mr. Lockyer's article in Nature, in order to make the theory more widely known. I believe meteorologists are on the track of a most important law. I would not expect the maximum and minimum rainfalls in every place to coincide with the sun-spot maximum and mini- mum so completely as that given above. Possibly in some places the figures might be reversed, owing to a changed direction in the water-bearing currents of the a'mosphere ; but that the changes occurring in the sun have a direct influence on rainfall there cannot, I think, be any doubt. E. Bonavia Lucknow, October 22 Inches of rainfall in Lucknow. The Radiometer and its Lessons I WISH that Prof. G. C. Foster had been more explicit in his answer to my letter ; for as it is I cannot understand to what "variations of density" he refers. So far as I know there are no variations of density in the gas in question except those which arise from variations of temperature ; but these variaions of density certainly do not affect the rate at which heat diffuses into and through the gas, for this rate is independent of the density and for the same gas depend only on the absolute tem- perature and on the degradation of temperature in the direction in which the diffusion takes place. The variations of tempera- ture do affect the rate of communication but only in proportion to the square root of the absolute temperature, and hence, in the case of the radiometer, only to an inappreciable extent. It is obvious that the law of diffusion holds good only so long as the gas is undisturbed by convection currents. Such currents, which certainly exist, increase the rate at which heat is communi- cated to the gas, that is to say, the hot surface instead of being exposed to the action of still air is exposed to a wind which t^nds to increase the rate of cooling. Bat the velocity of the wind does not increase with the rarefaction, and the cooling effect of a wind of a certain velocity does increase with the density 'of the air. Hence, as I pointed out in my first paper, the motion of the air will favour the force resulting from the communication of heat less and less as the rarefaction is increased. As regards Mr. Johnstone Stoney's theory. The post which brought me this week's Nature brought me also a paper from Mr. Stoney, on which I venture to comment. In doing this, however, I may say that I have no wish to criticise what Mr. Stoney has written. The fact that Mr. Stoney has in no way referred to my work, although I preceded him by some two years, has relieved me from all obligation to discuss Mr. Stoney's theory ; and I certainly should not do so now were it not that, as Prof. Foster has instanced this theory as disproving what I believe to be the truth, I feel bound either to show wherein it is wrong or acknowledge rtiy inability to do so. In the paper which I hive just received, 1 Mr. Stoney start s with an assumption that, hut for the effect of pravitation, "a flat stratum o'^gas in contact with a hot surface, A," and "everywhere subject to the same pressure" can exist in a state of equilibrium " except at the limits," without any passage of heat from the hotter to the colder part, although " within the stratum the temperature gradually decreases, from within outwards, from B^ the temperature of A to 0.^ the temperature of the surrounding gas." In support of this assumpt^oa 1 cann A fin i that any prooi is offered except that which is contained in the following portion of a sen- tence : — "We know, from familiar experiments, which show gases to be bad conductors of heat, that after the brief interval of adjustment a permanent state would ensue in which there would be no further change of density, or motion of heat, except by radiation." Now this assumption and the statement in support of it — in both of which Mr. Stoney seems to have ignored the very exist- ence of diffusion of heat in gases — are contrary to all experience as well as to the deductions from the kinetic theory of gases ; for it follows directly from the kinetic theory, and has been abundantly established by experiment, that under no circumstances can there exist a variation in the temperature of a continuous layer of gas without heat diffusing from the hotter to the cooler part. I think that I need say no more. This assumed condition of gas forms the base of all Mr. Stoney's reasoning, and although in a subsequent part of his paper he appears to me to have arrived at deductions which contradict his fundamental assumption, still this assumption may be held accountable for the anomalies which he has found. Osborne Reynolds November 17 ■ ■ I beg to call the attention of the readers of Nature to the following passage at the commencement of Mr. Crookes's lec- ture at the Royal Institution on February 11, 1876, "On the Mechanical Action of Light " : — " To generate motion has been found a characteristic common, with one exception, to all the phases of physical force." [Illus- trations are then given of the production of motion by heat, magnetism, electricity, gravitation, sound, and chemical force.] "But h^At, in some respects the highest of the powers of nature, /tas not hitherto been found capable of direct conversion into motion; and such an exception cannot but be regarded as a singular anomaly. "This anomaly the researches which I am about to bring before you have now removed ; and, like the other forms of force, light is found to be capable of direct conversion into motion, and of being most delicately and accurately measured by thj amount of motion thus produced." I cannot but suppose that Mr. Crookes and Prof. Carey Foster have alike forgotten the existence of this passage. If it does not convey an interpretation of the phenomena of the radiometer which is now admitted on all hands to be wront.', and imply a claim to the discovery of " a new mode of force," I am^incapable of understanding the meaning of words, I may add that one after another of my eminent scientific I " On the Penetration of Heat across Layers of Gas," Scientific Trans- actions of the Royal Dublin Society, November, 1877. 62 NATURE \_N0V. 2 2, 1877 friends has assured ma that I was perfectly justified in my statement on this point ; and it was by one of these, who was present at the lecture in question, that I was informed of the very explicit statement made on that occasion by Mr. Crookes of the views he then held, which were universally understood in their plain common-sense meaning, November 20 William B, Carpenter Fluid Films With reference to Mr, Sedley Taylor's interesting note on Fluid Films, allow me to say that if a drop of water, clinging to the outside of a glass gobkt, be lightly dusted with lycopodium powder, and a fiddle-bow be drawn across the edge of the glass, the drop will exhibit vortices, rotating in opposite directions. Highgate, N., November 19 C. Tomlinson Tuckey and Stanley.— The Yallala Rapids on the Congo Capt. Tuckey is dead and goKe and cannot answer for him- self ; it may therefore, perhaps, serve to clear his memory in some measure of a doubt about the correctness of his description of the Yallala Rapids in 1816, arising from the very different account of them given by Stanley sixty years afterwards, if I mention one of several facts in connection with American rivers. The late Sir J. Franklin, in his first and disastrous overland journey to the Arctic Sea in 1821, describes the " Bloody Fall" on the Coppermine River as "a shelving cascade about three hundred yards in length, having a descent of ten or fifteen feet." Betwetn 1848 and 1851 this "fall" was visited five times ; on one or other of such occasions the water was either at high spring flood, at low summer level, or at an intermediate elevation, yet under none of these conditions was the "fall" found to be more than thirty yaj'ds long, if so much, the height being about fifteen leet. Franklin and the officers with him were most careful and cor- rect observers, so that I can only attribute this wonderful change (from three hundred yards long to thirty) in the form of the cas- cade to the wearing away of the material forming the bed of the river, by the action of the water, assisted in a great measure by the large masses of ice and the stones carried down with it during the breaking up of the navigation in the course of thirty seasons, only half the interval of time between Tuckey's and Stanley's .visits to the Congo. Supposing a somewhat similar attrition, but in a less rapid manner, to have been going on at the Yallala Rapid, the description given by the former as he saw it may be equally correct as that of the latter when he visited it in its altered shape In 1877. May I add that a cataract may become a fall or a series of falls, and vice versd, according as the water in a river is in flood or at low level. J. Rae Scientific Club, November 16 The Future of our British Flora It may interest Mr. Shaw to know that the stations given by Lightfoot in his " Flora Scotica, 1777," still exist (as far as I am aware, and I have visited by far the greater number of them) at the present day. Experience has led me to the conclusion that a plant however maltreated, does not become extinct unless the natural cottdiiions are changed, as by the draining of a marsh, &c. I have over and over again found plants in stations where they were reported as "extinct years ago." Perhaps if Mr. Shaw visits his station for the " Lizard Orchis " (is this Orchis hircina, L. ? if so it is, I fancy, new to Scotch botanists) in the course of a year or two he may find it in as large quantity as ever. As regards the maltreatment of plants, I agree with what Mr. Shaw says respecting professors of botany. Each teacher of the science ought to teach his students that it is a crime to extermi- nate a plant, and that they can best learn botany from the observation of the common plants of their district ; there is great room for improvement in this respect. While a s udent I was often disgusted by seeing rare plants torn up and then cast away as if they had" been a handful of grass, or, worse still, put in the vasculum and forgotten till the next Saturday, when they were" thrown away ; and all this without a word of remonstrance from those who ought to have exercised authority, "that's villainous, and shows a most pitiful ambition in the man who uses it." Provided we reform a little, I do not think that, judging of the future by the past we have any reason to expect a large decrease in the ranks of our native flora. I do not supposa any species given by Lightfoot 100 years ago has become extinct even in his stations, and on the other hand we have had a consider- able number added to it since his time. Edinburgh A. Craig-Christie Selective Discrimination of Insects In continuation of the interesting observations of " S. B."" on selective discrimination of insects in Nature, vol. xvi. p. 522, permit me to send you the following notes from my journal, made in August last : — •* Watched by the roadside near Kew Bridge Station, several species of Hymsnoptera, of the genus Bumbus principally ; one visited thirty flowers of Lamiun purpiircum in succession, passing over without "notice all the other plants in flower on the same bank — species of Convolvulus, Rubus, Solanuvi. Two other species of Bombus and a Pierisrapa; also patronised i\iQ Lamium, seeking it out deep in the thicket, thrusting their probosces even into withered cups, although the Rubus' flowers were far, more accessible and seemed much more attractive, being fresh and well-expanded. " On the same bankseveral species of Diptera — »S)7-//«« chiefly — were visiting the Rubus, ignoring the Lamitcm. On another bank, some distance removed from t'ae first, I observed, how- ever, that the diptera were visiting the Latnium (one species was very busy on the convolvulus, applying its proboscis to the external aspect of the anther) while the Hymenoptera, species of wasp, were giving their attention to the Rtibus.'' I am sorry not to be in a position to identify the species of Hymenoptera and Diptera, being unable to capture specimens of either. Henry O. Forbes Highgate, N. The Earth-worm in Relation to the Fertility of the Soil In your number of the 8th instant there are some interesting remarks upon the habits, &c., of the common earth-wnrm. From frequent observations I fully concur with the remark that the worm does not consume living vegetation but only vegetable matter undergoing decomposition. I am also rather inclined to the opinion that there are (or may be) two reasons for the drawing in to their holes dead leaves, &c. , the one being, for use as food, and the other to protect the holes from a too plentiful supply of water. In this same connection I may mention what I have not before seen mention of, namely, the little mounds of small gravel stones which the worms heap up around the entrance to their holes. These are very curious and may be partly to prevent the entrance of water ; and also, as I think, partly for rubbing against the worm's slimy body, as fish do. It is very remarkable the extent to which loose gravel-stones (some as large as a hazel-nut, and even larger) are removed from a gravel-walk from distances quite beyond a foot, leaving the walk pitted all over. I have never seen a worm in the act of moving these stones and it is difficult to imagine how it is done, but as it generally takes place in wet weather, it may probably be by an adhesion of the stone to the slimy body of the worm. As regards fertilising eff'ects, it would be interesting to know whether the earthy matter composing worm-casts had passed through the worm's body, as the writer supposes, for in that.case it would probably have more fertilising properties than if consisting merely of the natural soil thrown up as by moles. The remark by one of your correspondents as to his observation of a line of darker soil thrown up by worms from a substratum of ashes deposited a considerable time before, would almost make it appear that the molc-like action above referred to took place. The writer, however, repeats his conviction that the matter composing worm-casts has passed through its (the worm's) body- 31, Stockwell Park Road Geo, H. Phipps Smell and Hearing in Moths "J, C," seems to draw inferences that moths have not the power of smell but have that of hearing. I feel quite certain they possess the former, but am in doubt about the latter. For the purpose of catching moths I use a preparation of beer and ISIOV, 2 2, 1877] NATURE 63 sugar boiled together, to which (after boiling) is added a little spirit, placing rags several folds thick, saturated in the pre- paration, upon garden-seats, low branches of trees, &c. I have in one evening taken as many as thirty-six moths (including red-, yellow-, crimson-underwing, swordgrass, angleshade, &c., &c.). What has attracted them unless smell ? or what generally leads them to their food ? With reference to the sound of the glass, is it not the quick motion of the hand which disturbs the moth ? E, H. K. Carnivorous Plants Prof. Serrano Fatigati, of Ciudad Real (Spain), has made some investigations upon two insect-feeding plants which he found during his last excursion to the province of Cordova, and on the general peculiarities of viscous plants during their flower- ing. The first of these plants is Ononis natrix ; it grows at Sierra Palacios. The second appears to be Sdene viscosa, and was found on the hill which connects the village of Belmery with the station. The experiments made upon these plants prove that when alive they were both covered abundantly with a viscous fluid, which in Silent was still visible after the specimens had been dried for four months. Prof. Fatigati has observed in several instances that every insect which touches their surface, and remains adherent to them, dies in a very few minutes. Remains of ani- mals in different stages of decomposition may be seen on the plants he possesses. The microscopical study of these plants has enabled the struc- ture of their secretory glands to be examined. The glands of the plant Ononis are at the extremity of hairs composed of cylin- drical cells, and are ovoid and multicellular. The protoplasm of the cylindrical cells always forms a parietal coating to the cell-wall. The glands of the Silene are simply conical epider- mical protuberances, and are divided into two cells at the close of their development. Prof. Serrano Fatigati has observed that in these species and in Cistus ladaniferus the secretion of the viscous fluid increases during their period of flowering ; he is studying this matter, in order to ascerta-n whether this circumstance bears any connec- tion with the production of heat and carbonic acid possessed by plants during the flowering period. Francisco Ginez Espar;eros 9, Madrid OUR ASTRONOMICAL COLUMN Minor Planets. — Mr. J. N, Stockwell, of Cleveland, Ohio, who has had much experience in calculations re- lating to the small planets, draws attention to a curious circumstance connected with the observations of Gerda, discovered by Prof. Peters at Clinton, N.Y., on July 31, 1872. It had been supposed that this planet was ob- served again in 1873, 1876, and 1877, but on forming equations of condition for the correction of the elements, Mr. Stockwell found that the observations of 1873 are quite irreconcilable with those of the other opposition?, or that some incompatible conditions had been introduced into the equations. " The discovery of these incom- patible conditions," he writes, " has been the occasion of an unusual amount of trouble and annoyance, and will be the source of future mortification, should the explanation at which I have arrived ultimately prove to be erroneous." Mr. Stoukwell's conclusion is this, that notwithstanding the planet observed from September 27 to November 12, 1873, was very near the computed place of Gerda, it was really another body that was observed in that year. To decide this point he calculated an orbit upon the observa- tions of 1873, which it appears are very well adapted to furnish reliable results, and finds the following elements, placing the elements of Gerda, as perturbed to the same date, in juxtaposition for the sake of comparison. The epoch is 1873, November 7*0 M.T. at Washington, longi- tudes from M.Eq. i873'o : — Planet of 1873. Gerda. Mean long. 35 4 57 213 14 38 178 53 9 I 36 3 I 58 40 6i3"-6390 35 47 14 208 19 29 178 56 40 1 36 19 2 o 51 6 14" -3842 It will be seen that four of the elements of the planet of 1873 are almost identical with those of Gerda, while the lines of apsides differ about five degrees. The actual distance of the planets from each other on November 7 would be 00188 of the earth's mean distance from the sun. Mr. Stockwell adds, " if there are really two planets moving in orbits so extremely near together, it must happen in the course of time, unless the mean distances are exactly the same, that they will approach each other so closely that their mutual perturbations will cause them to unite and form a single planet." A similar case of near coincidence between the orbits of two minor planets is that of Fides and Maia, to which attention was first directed we believe by M. Lespiault, of Bordeaux. In 1876 the elements were as follow : — Epoch .. Mean long. Fides. July 27-0 Berlin^M.T. - 326 33 33 ••• 66 27 20 ... 8 15 15 ... 3 6 49 ... 10 II 21 826" "441 7 Maia. Oct. 4-5 Berlin M.T. ... 2°7 37 21 ... 48 8 26 8 17 I 3 5 40 ... 10 4 31 824" -6400 Here, however, the planets are much further from each other than in the case of Gerda and the planet of 1873. At present Gerda and its companion will not be favour- ably placed for observation, but in the ensuing year no doubt an effort will be made to decide if there are really two bodies revolving in such near proximity to each other. Questions of much interest may arise if this should prove to be the case. The discoveries of minor planets during the present year now stand as follow : — No. 170, Myrrha, January 10, by Perrotin, at Toulouse. ,, 171, Ophelia, January 13, by Borrelly, at Marseilles. ,, 172, Baucis, February 5, ,, ,, .. 173. August 2, „ „ M 174. September 2, by Watson, at Ann Arbor, U.S. M 175. October 14, by Peters, at Clinton, U. S. M 176, November 5, by Paul Henry, at Paris. M 177. November 6, by Palisa, at Pola. A planet, November 12, by Watson, at Ann Arbor. We adopt Prof, Peters' name for No. 170, instead of the inappropriate one proposed in France. The Comet of 1672.— Madler has pointed out a distant resemblance between the elements of the comet of 1672 calculated by Halley, and those of the comet of 1 81 2, which has been found to have a period of revolution of about seventy years, and which therefore might h tve been in perihelion in the former year. The comet of 1672 was observed by Hevelius from March 6 to April 21, and also by Richer off the coast of Africa during his voyage to Cayenne, from March 15 to the end of the month, though he only described its position roughly. The observations of Hevelius are published in the rare volume of his " Machina Ccelestis " (of which, by the way, the British Museum possesses two copies), and we believe in the small special publication issued at Dantzig in the same year, and entitled, " J. Hevelii, Epistola de Cometh, anni 1672, Gedani observato, ad Henricum Oldenburgium," Halley's orbit gives for three dates of observation by Hevelius, adopting his corrected times, the foUo*ving positions : — G.M.T. R'ght Ascension. Deciination. h. m. o / o ' 1672, March 6, at 15 39 ... 353 16 ... 34 57 N. „ 15, at 7 44 - 18 2 ... 3725 „ ,, 29, at 8 8 ... 5221 ... 30 21 N. Without attempting an accurate reduction of the Dantzic observations, it may be seen that they agree sufficiently well with the positions deduced from Halley's orbit to render it probable that his elements would not be so far changed by a calculation from the improved places as to bring them materially closer to those of the comet of 64 NATURE \_NoV, 2 2, 1877 1812, the re-appearance of which is shortly expected. We have already mentioned that sweeping-ephemerides have been prepared by Herr Mahn, of Strasburg, and may be found in " Vierteljahrsschrift der Astronomischen Gesellschaft, 12 Jahrgang, 2 Heft." MR. DARWIN AT CAMBRIDGE AS we intimated last week, the honorary degree of LL.D. was conferred on Mr. Charles Darwin at Cambridge on Saturday. The occasion was in many ways remarkable, and suggestive of reflections that must occur to all, and which need not be put formally into words. The university seems to have been conscious of the honour Mr. Darwin was doing it, and seldom, it is said, was a more exciting scene seen in the senate-house. To appoint a special congregation of the senate for the transaction of no other business but the con- ferment of a solitary degree, although it be honoris causa, is only resorted to in exceptional and important cases. The step taken by the university evidently has met with general approval to judge by the tone of the assembly in the senate-house on Saturday. The building was packed, and the inevitable pastime of the undergraduates assume! a form extremely appropriate, however questionable its taste may have been. The appearance of Mr. Darwin entering the senate- house by a side door, with the Master of Christ's, of which College Mr. Darwin is a member, was the signal for a burst of applause which was evidently the result of genuine enthusiasm, and was certainly thoroughly hearty. At two o'clock the Vice-Chancellor took his seat on the raised dais, and the business of the day began. Standing side by side with Mr. Darwin in the centre of the senate- house, Mr. Sandys, the Public Orator, commenced the delivery of the customary Latin oration. Interruptions from the galleries occasionally interfered with the orator's efforts to make himself heard, but the pleasant manner of his delivery, combined with great tact and judgment, helped to quiet the undergraduates' " chafif,"^ and assisted him materially in getting through his task. We have been favoured with a copy of the Public Orator's address, which our readers will no doubt read with interest, both on account of the elegance of its Latin, and for its neat summary of Dr. Darwin's work ; indeed, in its way, it is somewhat of a literary curiosity. " ORATIO AB ORATORE PUBLICO HABITA CANTABRIGIAE DIE XVII° NOVEMBRIS A, S. MDCCCLXXVIl " DiGNlssiME domine, domine Procancellarie, et tola Academia : — " Meministis Horatianum illud, ' fortes creantur forti- bus ' ; vix igitur necesse est commemorare viri huius de rerum natura optime meriti patrem fuisse medicum egre- gium, avum poetam quoque insignem. ' Doctrina sed vim promovet insitam ' ; iuvat igitur recordari pueritiam huius fovisse scholam celeberrimam Salopiensem ; adu- lescentiam aluisse non modo Caledonicas illas Athenas, sed in hac etiam Academia Miltoni nostri Collegium. Tanti in laudem alumni, nisi fallor, ipsa paterni fluminis nympha, non immemor hunc primum patefecisse insu- larum corallinarum originem, ilia inquam Sabrina quae Miltoni in carmine vivit, curalio nitida roseum caput exseret unda, frontemque tam venerabilem sua praecinget corolla. " Quanta cum voluptate accepimus insularum illarum circulos, sese e vadis sensim attollentes, quasi florum irnmortalium palmarumque victricium corona locos illos \irides placidosque in Oceani campo designate, ubi priores insulae depressae et sepuUae sunt. Quam facete describit, quo modo varios sensuum affectur expriman': indices illi \u;tus et ipsa tacitorum oculorum eloquentia ; quo more apes, dum dulce illud nectar e flore delibant, quod continuandae floris stirpi utile sit, ipsae aliunde referant. Quam venuste explicat, quo modo captet Venus ipsa muscas ; quali ex origine sint Veneris volucres, ' raucae, tua cura, palumbes ' ; quibus cantuum illecebris, quo splendore plumarum, concilientur volucrum amores. Quam familiariter, velut rex ille excellenti sapientia, de tot rebus disserit, quicquid volat, quicquid natat, quicquid serpit humi ; quam varia eruditione disputat de fabuloso illo lepadum balanorumque marinorum genere, de mon- tium igneorum miraculis, sed idem de gracili vitis pam- pino et lentis hederarum bracchiis in apricum enitentium ; quanta liberalitate in patrocinium suum vindicat non modo 'aurea pavonum saecla,' sed etiam minus pulchram simiarum familiam. Qua de re quanquam poeta vetus dixit, ' simia quam similis nobis ' ; nobis tamen, viri Academici, cum oratore Romano, viro Academicae prae- sertim philosophiae dedito, gloriari licet, * mores ' esse * in utroque dispares.' " Illud certe extra omnem controversiam constat, pul- chrum esse tantam rerum naturae varietatem contemplari, regiones remotas invisere, silvarum incaeduarum solitudi- nem penetrare, insularum prope ignotarum recessus per- scrutari, varias denique animalium formas comparare inter se et distinguere ; pulchrius, haec omnia accura- tissime observata aliorum in usum voluptatemque lit- terarum mandare monumentis ; omnium pulcherrimum, infinita talium rerum multitudine ad leges quam paucissi- mas revocata^ipsum fontem et originem omnium repetere. Quanta igitur laude vir hie dignus est, qui adhuc iuvenis, aliorum magis quam suo commodo, tot terras lustra verit, lustratas feliciter descripserit ; qui maturiore aetate, tot generibus animantium et earum rerum quas terra gignit diligenter investigatis, illi praesertim legi constituendae operam dederit, qua docere conatus est, ita e perpetuo prope ad internecionem debellantium certamine aptissi- mam quamque novae stirpi propagandae speciem vivam victricemque superesse, ut tot species inter se diversae alia ex alia minutatim per immensam annorum seriem generari potuerint. ' Usus et impigrae simul experientia mentis paulatim docuit pedetemtim progredientes. sic unumquicquid paulatim protrahit aetas in medium ratioque in luminis erigit oras. namque alid ex alio clarescere et ordine debet omnibus, ad summum donee venere cacumen.' " Tu vero, qui leges naturae tam docte illustraveris, legum doctor nobis esto. "Duco ad vos Carolum Darwin." The conclusion of this oration was greeted with loud applause, and the proceedings ended with the Vice- Chancellor conferring the degree on Mr. Darwin in the usual foimal manner. In the evening the anniversary dinner of the Cambridge Philosophical Society was given in the Hall of Clare College. The president of the Society, Prof. Liveing, occupied the chair, and among the visitors present were Professors Huxley, Ramsay, Tyndall, Parker, Burdon Sanderson, Drs. Giinther, Wilks, Pye Smith, Mr. Francis Galton, &c. Prof. Ramsay proposed the toast of the University of Cambridge, and Prof. Huxley responded to that of Mr. Darwin, who was unable to be present. In his speech Prof. Huxley sarcastically spoke of the Uni- versity as reserving its highest honour till all other distinctions had been heaped on Mr. Darwin, that its own chaplet might crown the whole, and not be covered up. Prof. Huxley spoke of Mr. Darwin as the foremost among men of science, with one exception, since the days of Aristotle. A special meetiag of the Philosophical Society is to be held next Monday in the combination room of Christ's College, to consider the best means of making a permanent memorial of Mr. Darwin in the University. Would not a Darwin Professorship of General Biology be a very suitable memorial 1 Nov. 2 2, 1877] NATURE 65 INTERNATIONAL GEOLOGICAL CONGRESS AT the late meeting of the American Association for the Advancement of Science at Nashville, Tenn., Dr. T. Sterry Hunt presented a report on the above subject, of which at the time we gave a brief note. The following extracts, which have been sent us, will no doubt be more satisfactory to geologists : — " The committee to arrange for an International Geo- logical Exhibition and Congress, to be held in Paris in 1878, was appointed by this Association at Buffalo in August, 1876, and consisted of Messrs. W. B. Rogers, James Hall, J. W. Dawson, J. S. Newberry, T. Sterry Hunt, R. Pumpelly, and C. H. Hitchcock', together with T. H. Huxley for England, O. Torrel for Sweden, and E. H. von Baumhauer for Holland. At a meeting of the committee at Buffalo on August 25, 1876, James Hall was chosen chairman, and T. Sterry Hunt secretary. It was then agreed to prepare a circular setting forth the plan of an International Geological Exhibition, which should form a part of the general exhibition to be held at Paris in 1878, and indicating a scheme for the organisation of the geological collections to be sent thereto by the nations taking a part in that exhibition, and moreover, proposing an International Geological Congress to be held at Paris. " The circular in accordance with this plan was duly prepared, and printed in English, French, and German, and before the end of the year had been sent by the secretary to the principal scientific societies and academies, as well as to the workers in geology throughout the world. The response to this invitation has been most gratifying. The Geological Society of France has for- mally recognised the great importance of the objects proposed, and promised its hearty co-operation, while private letters from its president to the secretary of the committee, and from Prof. Hubert to Prof. Hall, give cordial assurances of the same kind. Spanish and Italian geologists have translated and published the circular in their respective languages, and have communicated to the secretary their hearty approval of the plan. Prof". Capellini has, in this connection, published an interesting correspondence, calling attention to the fact that in 1874 he had laid the project of a similar International Geolo- gical Congress, to be held in Italy, before tfie Italian Minister of Agriculture, Industry, and Commerce. " The Geological Society of London and the Geological Survey of Great Britain have also formally signified their approval of our objects, and the co-operation of Norway, Sweden, Russia, and Austro-Hungary, is promised. It is to be regretted that Germany has declined to take a part in the International Exhibition of 1878, but we trust that this will not prevent her geologists from joining in the proposed Congress. The director of the Geological Survey of Japan promises to aid in our work, and we have the same assurance from Brazil, where the circular has been translated into Portuguese. Chili and Mexico have also responded, and promise an ample representa- tion of their geology at Paris next year ; while Canada, both through her Geological Survey and in the person of Dr. Dawson, will probably be represented there. "The Government of the United States has as yet failed to accept the invitation of France to take a part in the Exhibition of 1878, so that American geologists are not certain that they will be able to participate in the Interna- tional Geological Exhibition of 1878. We are, however, assured that the Government is very desirous to have our country duly represented at Paris j and it is to be hoped that at the approaching extra session of the United States Congress, measures will be taken for accepting the French invitation, and appointing a commission, so that our people may secure a representation in Paris. I am assured, on all sides, that our geologists desire to con- tribute largely to the International Geological Exhibition, and even at this late day it will be possible to do much. In any event it is probable that several members of our committee will be present at the proposed Geological Congress. The precise date of this has not yet been fixed, though your secretary is now in correspondence with the Secretary of the Geological Society of France upon this point, and believes that with the co-operation of that body a time convenient to all -will be agreed upon. " It is recommended by the Standing Committee of the Association that, in addition to the names of Prof, J. P. Lesley, of Philadelphia, and Prof. A. C. Ramsay, director of the Geological Survey of Great Britain, already added to the International Committee, the presidents for the time being of the Geological Societies of France, Lon- don, Edinburgh, and Dublin, of Berhn, of Belgium, Italy, Spain, Portugal, and the Imperial Geological In- stitute of Vienna, be invited to form part of our Com- mission. T. Sterry Hunt " Secretary of the International Committee." Shortly after the presentation of the above report, the secretary received official notice that the Geological Society of France had, in co-operation with the above plan, appointed at Paris a local committee of organisa- tion for the proposed Congress, constituted as follows : — Hcbert, President ; Tournouer and Albert Gaudry, Vice- Presidents ; Bioche, Treasurer ; Jannetaz, Secretary- General ; Delaire, Sauvage, Brocchi, and Velain, Secre- taries ; with the following : Belgrand Bureau, de Chan- courtois, G, Cotteau, Damour, Daubrde, Delafosse, Delesse, Descloizeaux, Desnoyers, Fougud, V, Gervais, Gruner, De Lapparent, Mallard, Milne- Edwards, Pellat, Marquis de Roys and L, Vaillant, Members of the Committee, A circular issued by this committee bearing date July 31, invites all those interested in geological, mineralogical, and palajontological studies to take part in the approach- ing congress, and to subscribe the sum of twelve francs each, which will give a card of admission to the Congress, and right to all the publications thereof. All those who intend to be present are at the same time invited to send, as soon as possible, a list of the questions which seem to them worthy of general discussion, as well as of the communications which they propose to make touching these questions. They are also invited to indicate the date which appears to them most convenient for the meeting of the Congress, As regards an International Geological Exhibition, the Paris Committee of Organisation state that the difhculty of finding a suitable locality seems to them an obstacle in the way of realising this part of the programme. Ttiey hope, however, that there will be many special collections sent, and beg the exhibitors of such to give the committee due notice of these, in order that a special catalogue of them may be prepared. The secretary of the International Committee desires, in this connection, to call attention to the fact that his circular did not contemplate the holding of an Inter- national Geological Exhibition apart from the universal exhibition, but, in the language of that circular, the making as complete as possible the geolot^ical department of the universal exhibition. It is certam that, as at all previous similar exhibitions, the different nations will contribute more or less of geological material, and it was conceived that such collections, extended and syste- matised in accordance with the plan set forth in the circular, would, while forming a part of the universil exhibition, without farther cost meet all the requirements of an International Geological Exhibition, To the ac- complishment of this end it will only be necessary for the exhibitors of all nations to send a list of their geolo- gical contributions to the Local Committee of Organisation at Paris, All correspondeace relating to the Congress should be 66 NA TURE [Nov. 22, 1877 addressed to Dr, Jannetaz, Sdcrdtaire-g^n^ral, rue des Grands Augustins, 7, Paris, France; and all moneys sent to Dr, Bioche, at the same address. THE MODERN TELESCOPE THE gain to astronomy from the discovery of the telescope has been twofold. We have first, the gain to physical astronomy from the magnification of objects, and secondly, the gain to astronomy of position from the magnification, so to speak, of space, which enables minute portions of it to be most accurately quantified. Looking back, nothing is more curious in the history of astronomy than the rooted objection which Hevel and others showed to apply the telescope to the pointers and pinnules of the instruments used in their day ; but doubt- less we must look for the explanation of this not only in the accuracy to which observers had attained by the old method, but in the rude nature of the telescope itself in the early times, before the introduction of the micrometer ; the modern accuracy has been arrived at step by step. Fig. I. — A portion of the constellation Gemini seen with the naked eye. Let us see what the telescope does for us in the domain of that grand physical astronomy which deals with the number and appearances of the various bodies which people space. . Fig. 2. — The same region, as seen through a large telescope. Let us, to begin with, try to see how the telescope helps us in the matter of observations of the sun. The sun is about 90,000,000 of miles away ; suppose, therefore, by nieans of a telescope reflecting or refracting, whichever we like, we use an eyepiece which will magnify say 900 times, we obviously bring the sun within 100,000 miles of us ; that is to say, by means of this telescope, we can observe the sun with the naked eye as if it were within 100,000 miles of us. One may say, this is something, but not too much ; it is only about half as far as the moon is from us. But when we recollect the enormous size of the sun, and that if the centre of the sun occupied the centre of our earth the circumference of the sun would extend considerably beyond the orbit of the moon, then one must acknowledge we have done something (to bring the sun within half the distance of the moon. Suppose for looking at the moon we use on a telescope a power of 1,000, that is a power which magnifies 1,000 times, we shall bring the moon within 240 milts of us, and we shall be able to see the moon with a telescope of that magnifying power pretty much as if the moon were situated somewhere in Lancashire — Lancaster being about 240 miles from London. It might appear at first sight possible in the case of all bodies to magnify the image formed by the object-glass to an unlimited extent by using a sufficiently powerful eye- piece. This, however, is not the case, for as an object is magnified it is spread over a larger portion of the retina than before ; the brightness, therefore, becomes diminished as the area increases, and this takes place at a rate equal to the square of the increase in diameter. If, therefore, we require an object to be largely magnified we must pro- duce an image sufficiently bright to bear such magnifica- tion ; this means that we must use an object-glass or speculum of large diameter. Again, in observing a very faint object, such as a nebula or comet, we cannot, by decreasing the power of the eye-pie :e, increase the bright- ness to an unlimited extent, for as the power decreases, .'Nov. 2 2, 1877] NATURE 67 the focal length of the eye-piece also increases, and the eye-piece has to be larger, the emergent pencil is then larger than the pupil of the eye and consequently a portion of the rays of the cone from each point of the object is wasted. We get an immense gain to physical astronomy by the Fig. 3. — Orion and the neighbouring constellations. revelations of the fainter objects which, without the tele- scope, would have remained invisible to us ; but, as we know, as each large telescope has exceeded preceding ones in illummating power, the former bounds of the visible creation have been gradually extended, though even now we cannot be said to have got beyond certain small limits, for there are others beyond the region which the most powerful telescope reveals to us ; though we have got only into the surface we have increased the 3.000 or 6,coo stars visible to the naked eye to something like twenty millions. This space-penetrating poArer of the telescope, as it is called, depends on the principle that whenever the image formed on the retina is less than sufficient to appear of an appreciable size the light is apparently spread out by a purely physiological action until the image, say of a star, appears of an appreciable diameter, and iSxz effect on the retina of such small points of light is simply proportionate to the amount of light received, whether the eye be assisted bv the telescope or not ; the stars always, except when sufficiently bright to form diffraction rings, appearing of the same size. It therefore happens that as the apertures of telescopes i'lo. 4.— The Ncbu'a of Orion, reduced from Lord Rosses Drawing. increase, and with them the amount of light (the eye- pieces being sufficiently powerful to cause all the light to enter the e)e), smaller and smaller stars becoire visible, while the larger stars appear to get brighter and brighter without increasing in size, the image of the brightest star with the highest power, if we neglect rays and diffraction 68 NATURE \_N0V. 2 2, 1877 rings, being really much smaller than the apparent size due to physiological effects, and of this latter size every star must appear. The accompanying woodcuts of a region in the con- stellation of Gemini as seen with the naked eye and with a powerful telescope will give a better idea than mere language can do of the effect of this so-called space- penetrating power. With nebulae and comets matters are different, for these, even with small telescopes and low powers, often occupy an appreciable space on the retina. On increasing the aperture we must also increase the power of the eye- piece, in order that the more divergent cones of light from each point of the image shall enter the pupil, and therefore increase the area on the retina, over which the increased amount of light, due to greater aperture, is spread ; the brightness, therefore, is not increased, unless indeed we were at the first using an unnecessary high power. On the other hand, if we lengthen the focus of the object-glass and increase its aperture the divergence of the cones of light is not increased and the eye-piece need not be altered, but the image at the focus of the object-glass is increased in size by the increase of focal length, and the image on the retina also increases as in the last case. We may therefore conclude that no comet or nebula of appreciable diameter, as seen through a tele- scope having an eye-piece of just such a focal length as to admit all the rays to the eye, can be made brighter by any increase of power, although it may easily be made to appear larger. Very beautiful drawings of the nebula of Orfon and of other nebulae, as seen by Lord Rosse in his 6-foot reflector, and by the American astronomers with their 26-inch refractor, have been given to the world. The magnificent nebula of Orion is scarcely visible to the naked eye ; one can just see it glimmering on a fine night ; but when a powerful telescope is used it is by far the most glorious object of its class in the northern hemi- sphere, and surpassed only by that surrounding the variable star r] Argus in the southern. And although, of course, the beauty and vastness of this stupendous and remote object increase with the increased power of the instrument brought to bear upon it, a large aperture is not needed to render it a most impressive and awe- inspiring object to the beholder. In an ordinary 5-foot achromatic many of its details are to be seen under favourable atmospheric conditions. Those who are desirous of studying its appearance, as seen in the most powerful telescopes, are referred to the plate in Sir John Herichel's " Results of Astronomical Observations at the Cape of Good Hope," in which all its features are admirably delineated, and the positions of 150 stars which surround 6 in the area occupied by the nebula laid down. In Fig, 4 it is represented in great detail, as seen with the included small stars, all of which have been mapped with reference to their positions and brightness. This, then, comes from that power of the telescope which simply makes it a sort of large eye. We may measure the illuminating power of the telescope by a reference to the size of our own eye. If one takes the pupil of an ordinary eye to be something like the fifth of an inch in diameter, which in some cases is an extreme estimate we shall find that its area would be roughly about one-thirtieth part of an inch. If we take Lord Rosse's speculum of six feet in diameter the area will be some- thing like 4,000 inches ; and if we multiply the two to- gether we shall find, if we lose no light, we should get 120,000 times more light from Lord Rosse's telescope than we do from our unaided, eye, everything supposed perfect. Let us consider for a moment what this means ; let us take a case in point. Suppose that owing to imperfec- tions in reflection and other matters two-thirds of the hght is lost so that the eye receives 40,000 times the amount given by the unaided vision, then a sixth magnitude star — a star just visible to the naked eye — would have 40,000 times more light, and it might be removed to a distance 200 times as great as it at present is and still be visible in the field of the telescope just as it at present is to the unaided eye. Can we judge how far off the stars are that are only just visible with Lord Rosse's instrument ? Light travels at the rate of 185,000 miles a second, and from the nearest star it takes some 3^ years for light to reach us, and we shall be within bounds when we say that it will take light 300 years to reach us from many a sixth magni- tude star. But we may remove this star 200 times further away and yet see it with the telescope, so that we can probably see stars so far off that light takes 60,000 years to reach us, and when we gaze at the heavens at night we are viewing the stars not as they are at that moment, but as they were years or even hundreds of years ago, and when we call to our assistance the telescope the years become thousands and tens of thousands — expressed in miles these distances become too great for the imagination to grasp; yet we actually look into this vast abyss of space and see the laws of gravitation holding good there, and calculate the orbit of one star about another. J, Norman Lockyer (To be continued. ) ZOOLOGICAL GARDENS^ 'T^HE lists and reports of the various zoological gardens -■■ now before us show that much progress has lately been made by these as by other institutions connected with natural history. For though zoological gardens are looked upon by many as a simple form of amusement there can be no question that, when rightly conducted, they are not only mstructive in the highest degree, but also tend materially to advance the interests of the higher branches of natural science. All persons, therefore, who take an interest in the progress of science will be glad to see the number of zoological gardens increasing among the dependencies of this country and in other States. Of the first of the five works on our list we need say but little. The Gardens of the Zoological Society of London, in the Regent's Park, are too well known to most of our readers to require a lengthened notice. The chief additions to their unrivalled menagerie are recorded every week in our columns. The volume now before us contains a catalogue of all the species of vertebrated animals, of which examples have been exhibited during the past fifteen years, arranged in systematic order. The various specimens are distinguished by letters, and the date and mode of acquisition of each individual are added. Thirty-five woodcuts, most of which have originally appeared in the Society's Proceedim^s, illustrate some of the more remarkable forms. The result shows that from the commencement of the year 1861 to the close of 1875, there have been obtained for the collection in the Regent's Park, examples of no less than 2,143 species of vertebrated animals. Of these 570 were mammals, 1,224 birds, 227 reptiles, 39 batrachians, and 83 fishes. The catalogue of the animals in the newly-established Zoological Gardens at Calcutta, concerning the foundation and progress of which we have written at full length not long since,^ is next upon our list. It is drawn up after ^ (i) List of Vertebrated Animals now or lately living in the Gardens of the Zoological Society of London. Sixth Edition. 1877. (London : Longmans). (2) Li.st of Vertebrated Animals living in the Zoological Gardens, Calcutta, April, 1877. Printed at the Bengal Secretarial Presii. 1877. 8vo. (3) A Guide to the People s Park, Madras, wiih a description of the Zoological Collection contained therein. (Madras : Higgiubotham and Co , 1876) (4) The Fifth Annual Report of the Board of Directors of the Zoological Society of Philadelphia. Read at the Annual Meeting cf the Members aud Loanholders ol the Society, April 26, 1877. 8vo. (Philadelphia, 1877 ) (5) Report of the Director ot the Central Fark Menag-rie, Department of Public Pa-ks, City of New York, fer year i8;6. iNcw Yoik, 1877 : B. M. Lees. Printer, 210, Fulton St-eet. ) ^ Nature, vol xvi. p. 28. ISIOV. 22, 1877] NATURE 69 the fashion of the preceding, and has been prepared by Dr. John Anderson, the Superintendent of the Imperial Museum at Calcutta. It shows that though so recently in actual operation these gardens have already made con- siderable progress, and are able to show a good series of the better-known Indian animals for the instruction and amusement of the Calcutta public. Amongst others we may notice the Indian Otter {Ltdra leptonyx) and the Isabelline Bear, as animals which have not yet reached the Gardens of the Zoological Society of London. Alto- gether there are TJ species of mammals in the collection, 120 of birds, and 17 of reptiles. The " Guide to the People's Park " shows that Madras does not intend to be left behind the sister-city of Calcutta, and that she too will have a zoological garden. As its name imports, this little work is more of the nature of a " Guide " than a Catalogue. It appears that Madras is indebted to Sir Charles Trevelyan for the People's Park. Prior to 1859 the plot of ground which it now occupies formed " an im- mense swamp." In that year the enlightened governor of the day first suggested, and subsequently put into execution, the conversion of it into a park of about 116 English acres. (How glad would be the Council of the Zoological Society of London to have such an area at their disposal !) The collection of animals does not yet, it is true, appear to be very extensive ; but space, at any rate, does not fail them, and there is, at all events, plenty of room for additions, which cannot be said of some of the sister institutions. We must now turn to the western hem'sphere, and see what our Anglo-Saxon relatives on the other side of the Atlantic have done in the way of zoological gardens. In this matter, we must say, our usually energetic cousins seem to have moved a little slowly. Such vast and wealthy populations as those of New York and Phila- delphia might well have started zoological gardens for the instruction and amusement of their citizens years ago, and they would by this have been in possession of well- organised institutions. But although the subject has been mooted in both these cities for many years, it is only within these last few years, we believe, that anything very practical has been effected. , The Zoological Garden of New York forms a part of the Central Park of that city, and the report now before us is addressed by Mr. W. A. Conklin, the director, to the Board of Commissioners of the Department of Public Parks of New York. It gives us an account of the affairs of the Zoological Garden during the year 1876, and not apparently a very satisfactory one — since a reduction of the sum usuc.Uy appropriated (by the City of New York, we presume) to the Park was made that year, which rendered it impossible to keep up the Gardens on their usual footing. It was resolved " not to receive any animal for exhibition in the menagerie unless the owner furnished the necessary food." This measure and the diminution of the sum expended in new purchases seem to have caused a sad decrease in the number of animals exhibited in 1876. In spite of this the number of visitors was larger than in any previous year, which, however, is accounted for by the concourse of visitors passing through New York to and from the Centennial Exhibition at Philadelphia. While the Zoological Garden of New York is kept up out of public moneys that at Philadelphia is, like ours in London, the property of a private society, and appears to be in a much more flourishing condition. Here the *' Cen- tennial" told still more largely on the number of visitors than at New York, raising them to a grand total of more than 600,000 for the year ending April 30 last. The extra receipts from this source have not only enabled the society to make many important additions to its menagerie, but also to spend a considerable sum in improvements and new build- ings. Amongst the latter we notice " a house for the accommodation of warm-climated (!) hay-eating animals " (qu. zebras and antelopes ?) now under construction at an estimated cost of 18,000 dollars, which will apparently exceed in dimensions even the new lion-house of the Zoological Society of London. This is pretty well for a society only now issuing its fifth annual report. It is evident that in zoological gardens, as in other scientific institutions, Philadelphia means to "go-ahead" of her more populous neighbour. NOTES We take the following from the Times : — The Royal Society medals for the present year have been awarded by the President and the Council as follows : — The Copley Medal to Prof. James D wight Dana, for his biological, geological, and mineralogical investiga- tions, carried on through half a century, and for the valuable works in which his conclusions and discoveries have been published. A Royal Medal to Mr. Frederick Augustus Abel, F.R.S., for his physico-chemical researches on gun-cotton and explosive agents. A Royal Medal to Prof. Oswald Heer, of Zurich, for his nume- rous researches and writings on the tertiary plants of Europe, of the North Atlantic, North Asia, and North America, and for his able generalisations respecting their affinities and their geological and cHmatic relations ; and the Davy Medal to Robert Wilhelm Bunsen and Gustav Robert Kirchhoff, for their researches and discoveries in spectrum analysis. This is the first award of the Davy medal, which, as will be remembered, was founded by the proceeds of the sale of the service of silver plate bequeathed for the purpose by Sir Humphry Davy. The medals will be pre- sented at the Society's anniversary meeting on the 30th inst. A FEW days ago the French Minister of Public Instruction, by a decree which has not yet been published, appointed a Com- mission to deliberate with the members of the council of the Observatory of Paris, as to the improvements which are pos- sible in the organisation of the establishment without inter- fering with existing decrees. Among the commissioners are Dr. Janssen, Director of the Meudon Physical Observatory, M. Herve Mangon, President of the Meteorological Society of France, and M. Marie Davy, the Director of the Montsouris Observatory. M. Yvon Villarceau and M. Loewy have been appointed as councillors. The first meeting of the Commission took place last Saturday, under the presidency of M. Dumesnil, one of the heads of the ministry, representing M. Brunet. M. Yvon Villarceau, the astronomer delegate, read a long and elaborate report on the improvements which it was considered desirable to make in the establishment. The Commission came to no decision, and the meeting adjourned to Saturday, Dec. i. Some of the members are desirous of separating the meteoro- logical department from the observatory, and either transfer it to Montsouris or establish a Meteorological Institute ; to accom- plish this long desired change it would be necessary to suppress the decrees signed by M. Thiers and approved by M. Leverrier. The intentions of the Government are not to alter radically the existing state of things, which works satisfactorily, but to im- prove it as far as possible. Public opinion is strongly in favour of the organisation consecrated by M. Laverrier's administration. Two volumes of the French Transit of Venus Reports are now going through the press, and will be diitributed in a very few days. The first is a compte rendu of the m'ssion in China, com- manded by Capt. Fleurian. The second \s 2^ prods verbal of the sittings of the Transit Commission, which was presided over by M. Dumas. It is known that M. Leverrier abstained from being present at its deliberations, the illustrious astronomer being one of the few opponents of the transit observation. He preferred the opposition of Mars or direct measurements as taken by Cornu in his experiments on the velocity of light. The French Government intends to send out an expedition to San Francisco in order to observe the next transit of Mercury, which will take place on May 6, 1878. 10 NATURE [pOV. 22, 1877 At the meeting of the Paris Academy of Sciences, on Novem- ber 12, M. Faye presented the volume of the " Connaissance des Temps" for 1879. This publication has reached, according to M. Faye, the highest degree of perfection desirable, and the new volume is marked by two important improvements both due to M. Loewy. The first consists in a new method which enables longi- tudes to be calculated according to occultations of stars by the moon, and that with such facility that sailors will make use of them with great benefit. The second improvement consists in tables which enables the latitude to be obtained by observation of the polar. The death of von Baer has made a foreign associateship in the Paris Academy of Sciences vacant, and MM. Bertrand, Fizeau, Becquertl pere, Claude Bernard, Dumas, and H. St. Claire Deville, have been appointed a commission to prepare a list of candidates for the vacant " fauteuil." A PRIZE of 1,000 marks (50/.) is offered through Dr. Her- mann J. Klein, of Cologne, for the best treatise on "The Development of Monistic Philosophy from Spinoza down to the Present Time." The treatise must be written in the German lan- guage, and must contain a complete account of the relation of Spinoza to the Cartesian philosophy, a description of the progress and changes in the monistic theory brought about by Leibniz, Schopenhauer, Lazarus Geiger, and Ludwig Noire, and a clear definition of the differences between the materialistic and monistic theories. All details can be obtained from Dr. Klein. The term up to which treatises will be received is fixed for July 30, 1878. By a recent will, M. Maujean has bequeathed to the French Institute the capital producing a sum of 1,200 francs, designed to form a biennial prize of 2,000 francs, to be awarded alternately by the Academic Fran9aise, and by the Academic des Sciences. To obtain it of the latter, it is necessary to have published the work which shall be pronounced the most useful to hygiene, con- sidered in all its branches. The Berlin Aquarium suffered, on November 13, the loss of what was certainly, from a scientific and from a financial stand- point, the most valuable zoological specimen in Europe, viz., the famous gorilla Pongo, whose human-like form and playful antics became so familiar to Londoners during the past summer. The visit to England, and stay in its warm moist climate, was regarded as having had the best effect on Pongo's health, when he returned to Berlin on September 21, and there was every pros- pect of the animal's being able to live through his second northern winter. Five weeks later, a lessening of appetite and slight diarrhoea were observed, but were not regarded by the physician as of sufficient importance to prevent Pongo's appearance in public. The consternation was great when a few days later, the gorilla died suddenly, without any apparent increase of dangerous symptoms. The loss to the Berlin Aquarium is no small one, as it had lately refused an offer of 2,500/. for the animal, and, taken in connec- tion with the late deaths of their orang-outang and chimpanzee, will check somewhat the tendency to invest capital in anthro- poidal apes. Not less severe is the loss to the scientific public, for no animal of late years has so attracted the attention ot zoologists as Pongo, and theorists were looking forward with no slight degree of interest to the possibilities connected with his growth and education. After a dissection, which will probably reveal the cause of the sudden death, the skin will be handed over to the Berlin Anatomical Museum. We have received from Dr. Aguilar the annual volume of the Observatory of Madrid for the last year, 1876. It is a little late in the day, but we may call attention to the long and inter- esting article on geographical discovery with which the book terminates, seeing that that commences so early, "2400 (?) anos A. des J. C. Dispersion de las gentes despues del Deluvio. Del caos consiguiente a tan immensa catastrofe surgen a poco tiempo los tres grandes reinos de Babilonia, Ninive y Egipto." Already studied by two geologists, the Crimean peninsula has been recently visited by M. Ernest Favre, of Geneva. M. Hebert presented to the Paris Academy of Sciences, on Nov. 12, the results of this new examination, consisting of numerous sections on a very complete map. Hachette and Co. are about to publish an important work of reference in Chemistry containing such important matter as the coefficients of dilatation, the specific weight of vapours, refrigerating mixtures, numerical documents on quali- tative, quantitative, and spectral analysis, &c. We may state that the Smithsonian Institution are about to publish a similar work. There are now "on view" at the Westminster Aquarium four Laplanders — two men and two women — who have with them reindeer, dogs, an Arctic fox, a tent, sledges, and numerous articles of dress of home manufacture. They have been brought to England by Mr. Carl Bock, through the enterprise of Mr. Farini, so well known as the " inventor" of Lulu's "upward bound," Zazel's "lightning flight," and Maraz's "eagle swoop." Any entertainment announced by one whose greatest successes hitherto have been to puzzle the public as to "how it is done" will naturally be looked upon with the same kind of suspicion that was bestowed on the " Egyptians " in the recent Lord Mayor's show. In some cases the public enjoys being puzzled, and this adds a zest to the enterprises of those who devise how to puzzle them. In the case of these Laplanders there does not appear to be the slightest ground for any suspicion as to genuine- ness. It will be recollected that Mr. Farini's whale at the aquarium was genuine, and when the post-mortem was held under the direction of Prof. Flower it was shown beyond doubt that it was not made of vulcanite and kept going by clock-work as was popularly supposed. We draw attention to the visit of these Laps because there is much of interest to be learnt from seeing them, and we do so with all the greater pleasure because the aquarium, looked at from a scientific point of view, has fallen from its high estate. We cannot pretend to make it a com* plaint that it is in the evening practically a large music hall with a miscellaneous entertainment by comic performers and sword swallowers. The place cannot be kept open without money, and if the public will not pay to go to an aquarium pure and simple, the management must provide what the public will take to, or shut up the place. But what we fear is that the manage- ment has been too much neglecting that part of the public, the minority certainly, who do care for an aquarium. Occasionally, especially during the control of Mr. Cariington, the aquarium has been in good order and well-stocked. It is again getting very unsatisfactory, perhaps because Mr. Carrington is in Naples. We gladly mentioned such recent improvements as throwing several tanks jnto one to make a place for large fish, and the removal of the seals to the whale tank, where their gambols in swimming can be better seen, and we have on several occasions recorded interesting arrivals, and if we could honestly do so we would gladly recommend the tanks generally as affording a good opportunity for studying the habits of the occupants. Tho-agh the Laps are not especially connected with aquarium objects the building affords a centrally located home for them. The per- formance, if it may be so called, through which ihey go, is an illustration" of their quiet life, and happily there is no attempt to make it sensational. They show, among other things, how rein- deer sinew is worked into a continuous thread, a process of interest to those who have examined collections from bone caves containing implements which it is believed were used either with such threads or strips of reindeer hide. The size of some of the eyes of the bone needles is more suggestive of thread than strips. Their monotonous singing on the syllables iva wa wa, if not Nov. 2 2, 1877] NATURE 71 beau.iful, has an interest of its own as representing their secular music, especially when contrasted with their capability for singing Lutheran hymns. Schaferius gives the translation of some of their love songs. Have these dieJ out since his time ? Mr. Bock says they have no seculir songs. We are glad to know that the Zoological Society has given a friendly hand to Mr. Farini in offering a temporary home to five of his reindeer in the gardens, Mr. Bock states that the place from which he brought the party is Kautokeino, N. 69-/, E. 22*56. A REPORT has recently been presented to the State Board of Health i.i Massachusetts by Dr. Nichols, regarding the health of people who work with sewing machines. From observations by the medical men engaged it is inferred that a healthy person of average strength who does not make a business of sewing with the machine, may work from three to four hours daily without much fatigue or perceptible injury to haalth. Among work people, on the other hand, one frequently meets with disorders of digestion, due to sedeatary life and bad vea'.ilation, also pains in the muscles of the trunk and the lo»er limbs, because these la'.ter are always in motion. There occur a'so congestions of the ventral organs, weakness, and in some rare cases neuralgias of the legs and spinal irritations. It is recommended to the proprietors of works in whi:h the sewing machine is used, to have (i) a good ventilation ; (2) a shorter time forwoik, with periods of rest j {3) another motor force than that of the feet, ft^., a steam engine. An Indo-Chinese Society has just been formed in Paris for promoting the study of Transgangetic India and developing the trade of France in that region. The Juvenile Christmas Lecture at the Society of Arts will be by Prof. BarflF, on " Coal and its Components." The Moniteur Universel publishes an article on the manufac- ture of types for printing with hardened glass {verre trempe). It appears that the new types have worked admirably on the improved revolving press for continuous paper. The death is announced of Mdlle. Henrietta Cerf, who was born in Jamaica in 1810, and died in Brussels on the 22nd ult. Mdile. Cerf, who for some years resided near Dinant, communi- cated various articles on the botany t^f Kent and B.-lgiu^n to the Phytologisi. . . , ,' "'.' '; , Prince Bismarck's study at Varzin has been connected with the Foreign Office at Berlin by a telephonic apparatus. The demand for these instruments is said to be immense in Germany, A MONK of the monastery of Raigern, between Braun and Vienna, has completed a very curious mechanical work, a self-moving terrestrial globe, fourteen metres in diameter. A combination of wheels effects a revolution similar to that of the earth, and which lasts for three weeks. At the axis of the Noith Pole there are dials which indicate the days, months, &c. ; above this axis is another smaller globa which shows the rotation of the eanh around the sun. The large globe is set in motion by a dozen wheels. This ingenious mechanism has cost ten years' labour, and has only been achieved after many experiments. A map drawn upon the globe shows geographical details, and includes the most recent discoveries, routes of steamers, railways, telegraphs, mountain-heights, depths of the sea, &c. We have received a reduced photo-electrotype faciimile, by Mr. G. E. Emery, of Lynn, Mass., of the map which accom- panied the narrative of the brothers Zeni, published at Venice in 1558. The Zeni it will be remembered rnalc a voyage to the Arctic regions in the fourteenth century, and one of the problems of geography is to identify the places mentioned in their narrative and map. This has already been ably attempted by Mr. Major, and while Mr. Lynn's identifications agree in the main with those of Mr. Major, there are some important differences. " Icaria," e.g., which Mr. Major makes out to be Kerry, Irel ind, Mr. Lynn identifies with the Rockall Islands. The lost East Greenland Colony, the latter places on the east of Spitzbergen, apparently on Wiche Land, and most extraordinary of all, Crolandia, he maintains is the recently-discovered Franz-Josef Land. These two last identifications are very daring, and geographers will look with interest for Mr. Emery's reasons, which no doubt he will publish. Inteliigence has rea:hed the Royal Italian Geographical Society that the Ma'-quis Antinori, heading the Italian expedition of discovery in Africa, is dead. Chiarini, his fellow-traveller, is a prisoner in Abyssinia. A SECOND edition of Capt. Luigi Gatta's Italian translation of Mairy's "Physical Geography of the Sea" has just been published at Rome. It contains extensive and valuable footnotes by the translator. Capt. Gatta is, we understand, engaged in a translation of I^yell's " Principles of Geology," Dr. Harmand, who has been exploring in Cochin China, has arrived in France, bringing with him, we believe, results of much value. On October 18, the first pioneers of the International African Exploration Society, consisting of the two Belgian officers, Capts. Crespel and Cambier, and the naturilisf, Dr. Maes, left Southampton for Lake Tanganyika via Port Natal, on one of the vessels of the Union Mail Steamship Company. This Com- pany, with praiseworthy generosity, conveys the first party entirely free, and will make a deduction of twenty per cent, in the fares of all subsequently sent out by the society. The royal auspices under which the society enters upon its field of activity have ensured to it support in a variety of directions. The Sultan of Zanzibar has promised to render the utmost assl-tance possible, and the com- mercial houte of Roux de Fraissinet and Co., has instructed its widely-spread agencies on the east-coast to second the efforts of the exploring party. There seems to be no lack of fun is in the treasury of the society. Among the late subscriptions are 3,000 francs from the Hungarian Africm Society, while the collections in France amount already to 32,000 francs. Belgium, small as it is, contributed 300,000 francs outright in June last, while yearly subscriptions to the amount of 100,000 were given in addi- tion. There is every prospect that this magnificent united effort will succeed in solving some, at least, of the problems connected with the remaining terra incogn'ta of equatorial Africa. We regret to record the untimely end of the well-known geolo- gist and African explorer. Dr. Erwiu von Eary, whose recent explorations have frequently been referred to in our columns. Dr. V. Bary started in August, 1876, from Tripolis, on his journey into the interior of the Sahara, supported partly by the Karl Ritter Endowment Fund, and partly by the Berlin Afnkan- ische Gesellscha''t. The aim of this expedition was to make a thorough study of these ahnost unknown regions, with especial reference to topographical and geological questions, more par- ticularly the age and formation of the great desert. The chief resulsof this first journey were the observations leading to the conclusion that the Sahara was not formerly the bed of an inland sea as hitherto supposed. The traveller returned from this very exhaustive and fatiguing tour to the Berber town of Chat to recruit his impaired energies, and prepare for a more extended trip into the district of the Tuarej Hog^ar, which has not as yet been visited by Europeans. Here he met the sad fate of so many African explorers, and died on October 2, from the effects of excessive exposure and privation. Von Bary's varied qualifi- cations and complete devotion to the cause for which he perished, had led to high expectations among his fellow German geologisU, 72 NATURE [Nov: 2 2, 1877 and a general feeling of regret is felt over his eirly death, away from home and friends. The French geologist, M, Largeau, is at present endeavouring to penetrate into the Tuarej region from the north, and the interest previously centred on von Bary's investigations will now gather about his efforts. In the spring of the present year we referred briefly to the attempt being made by Dr. J. M. Hildebrandt, under the auspices of the Berlin Academy of Sciences, to ascend the snow- covered summit of Mount Kenia. The question as to the per- anent snow covering of the tw» equatorial mountains, Kenia and Kilimandscharo, has been a subject of so much controversy among geographers, that the results of this expedition have been looked for with great interest. It is with regret that we learn from a communication of Dr. Hildebrandt's, dated Suez, November 2, that he has been compelled to return, leaving the summit of Kenia still untrodden by the foot of a European. He left Mombassa on January 10 with forty attendants, and after two months of exhaustive travel amidst hostile tribes, reached Kitui, in Ukamba. Here, in full sight of Kenia, he was com- pelled to pause and retrace his footsteps, his followers utterly refusing to venture among the maraud ng tribes intervening between him and his journey's goal, and he himself being only saved by the swift application of an antidote from death by poison given by the natives. On reaching Zanzibar the physicians declared his health impaired to such an extent that restoration could only be hoped for in a more temperate clime. Dr. Hilde- brandt has suffered unusually from the two invariable concomitants of the African explorer — sickness and the hostility of the abori- gines, his two expeditions from Zanzibar in the spring and autumn of 1875 being both shortened and hampered by these causes. Herr Schutt, a civil engineer, has been despatched by the German African Society to*St. Paul de Loanda to undertake an expedition through the region lately traversed so successfully by the hunter. Dr. Pogge. One of the effects of the war in the east appears to be the discovery in out-of-the-way towns in Russia, of gems of unsur- passed size and beauty, which doubtless have been jealously hoarded by their possessors, and only brought to light in times, like the present, of national necessity. Some of these gems have naturally found their way to this country ; perhaps the most remarkable are — an aquamarine, far superior to anything before seen in England, weighing over six ounces and a half, without the slightest blemish, and of a deep sea-green tint ; also a topaz rivalling that purchased for the Grand Mogul at Goa for 11,260/. Ihese two remarkable gems were received from Moscow by Mr. Bryce M. Wright, Mineralogist, of Great Russell Street, the possessor of the unique suite of diamonds called the " Bryce Wright Diamonds," valued at 21,000/. We are requested to state that in the abstract of Mr. Perkin's paper read at the meeting of the Chemical Society on November I the word "cumenyl" was, by a slip, written "cinnenyl" throughout the report. The additions to the Zoological Society's Gardens during the past week include a Common Squirrel {Sciurus vulgaris), European, presented by Mr. T. Massey, F.Z.S. ; a Greater Sulphur-Crested Cockatoo {Cacatua gaknta), from Australia, presented by Mr. F. ;Lablache ; a Radiated Tortoise {Testudo radiata) trom Madagascar, presented by Mr. H. Harrison ; two Red-backed Squirrel Monkeys {Saimaris cerstedi), two Black- handed Spider Monkeys {Ateles melanochir), a Derbian Opossum {Didelphys derbianus) from Central America, a Bonnet Monkey (Macacus radiatus) from India, a Rufous-vented Guan {Penelope cristata) from Costa Rica, deposited ; a Bay Antelope {Cepha- lophiis dorsalis) from West Africa, received in exchange. THE LIBERTY OF SCIENCE IN THE MODERN STATED "XTlfHEN the honourable request was addressed to me by our ^ ' committee to deliver a lecture to the meeting upon this occasion, I asked myself whether I should not treat of a special department of the latest development of science, in accordance with that point of view to which I drew attention originally, and of which you were reminded by Prof. Klebs only the other day. But I decided this time to give expression to a more general want, principally because it seems to me that the time has come when a certain explanation must take place between science as we represent it and work in it, and general life as a whole, and because in the special history of the conti- nental nations of Europe the moment is rapidly approaching when the mental fate of nations by decisions in the highest quarters may be determined perhaps for a long time to come. It is not for the first time, gentlemen, that upon the occasion of a meeting of this Association I have been able, as a warning, to point out almost dramatic events happening in our neigh- bouring state. On a former occasion I could draw atten- tion to occurrences which had just taken place beyond the Rhine, and which, however far they may apparently be removed from our task, yet concern the same contested domain after all, that namely upon which a decision must be made with regard to determining what position modern science is to occupy in the modern state. Let us be sincere — here we may perhaps be doubly so, — it is the question of ultramontanism and of ortho- doxy, which moves us continually. I may say that I look forward with real fear to the events which will happen among our neighbours in the course of the next years. We here, at this moment, may look round with a certain pride and we may observe the course of things with a certain calmness. But to-day, when we are celebrating the fiftieth anniversary of this Association, it is certainly becoming to remember how great a change has taken place in Germany, and specially at Munich, since the days when Oken assembled German naturalists and physicians for the first time. I would only refer shortly to two facts ; they are well-known enough, but then they are also important enough to be mentioned again. The one is that when, in the year 1822, the handful of men who constituted the first meeting of the German Association of Naturalists met at Leipzig they thought it still so dangerous to hold a meeting of that description that it was really held in per- fect secrecy. The names of the Austrian members could indeed be published only thirty-nine years later, viz., in 1861. The second fact which strikes us when we remember Oken is, that he, the valued and renowned teacher, the ornament of the Munich high school, died in exile in the same canton of Switzerland in which Ulrich von Hutten ended his life full of troubles and contests. Gentlemen, the bitter exile which oppressed the last years of Oken's life, which caused his death far away from those scenes where he had sacrificed the best powers of his life, this exile will remain the signature of the time which we have gone through. And as long as there is a German Association of Naturalists, we shall thankfully remember that this man bore all the signs of a martyr until the time of his death, we shall point him out as one of those who with their blood conquered and obtained for us the liberty of science. Nowadays, gentlemen, it is easy to speak of the liberty of science in Germany; now we are perfectly secure even here, where, only a few decades back, the fear was great that a new change of things might perhaps produce the extreme reverse, and we can in all calmness discuss the highest and most difficult problems of life and the hereafter. The addresses which were delivered at the first and second general meetings certainly prove sufficiently that Munich is now a place which can bear to hear the representatives of science in the most perfect liberty. I was not able to listen to all these addresses, but I have since read those of Professors Haeckel and Nageli, and I must say we cannot ask more than to be allowed to continue to discuss with such liberty. If it were only a question of rejoicing over this possession I should indeed not have claimed your attention for that object. But, gentlemen, we have arrived at a point when it becomes necessary to investigate whether we may hope to retain securely for the future the possession which we actually enjoy. The fact that we are enabled to discuss, as we do to-day, is not a sufficient ' Address delivered at the Munich meeting of the German Association, by Prof. Rudolf Virchow, of Berlin. I^JOV. 22, 1877] NATURE 73 security that it will always remain so for one who, like myself, has had many years' experience of public life. Therefore I think that our efforts should not only tend to claim the attention of all for the moment, but I believe we ought also to ask ourselves what we are to do to maintain the present state of things. I will tell you at once, gentlemen, what I would represent to you as the chief result of my observations, what I would like to prove here principally. I would like to show that for the present we have nothing more to ask, but that on the contrary we have arrived at the point when we must make it our special task to render it possible, through our moderation, through a certain resignation with regard to personal opinions and prtdileclions that the favourable disposition of the nation towards us, which we now enjoy, does not change to the contrary ! In my opinion we are really in danger of doing harm to the future, by making use too amply of the liberty which the present slate of things offers us, and I would warn you not to continue in the arbitrariness of personal speculation, which now claims prominence in many domains of natural science. The explana- tions which my predecessors have given you, those of Prof. Nageli in particular, will yield a series of the most important points of view, with regard to the course and limits of natural knowledge, to all who read them, and it cannot be my task to repeat them. But I must point out in reference to them, and I would like to adduce a few practical instances from the experience of natural science, how great a difference there is between what we give out as real science in the stiictest sense of the word, and for which alone we may in my opinion claim the totality of all those liberties which we may designate as liberty of science, or, if we express ourstlves still more exactly, as liberty of sciejttifi: teaching, — and that larger domain, which belongs more to specu- lative expansion, which sets problems, and finds the tasks to which modem investigation is to be applied, and which antici- patively formulates a series of doctrines, which are still to be proved, and the truth of which must yet be found, but which in the mean time may be taught with a certain amount of proba- bility, in order to fill certain gaps in knowledge. We must not forget that there is a limit between the speculative domain of natural science and that which is actually proved and perfectly determined. The demand is addressed to us that this limit shall be not only occasionally pointed out, but fixed with the greatest exactness, so that each single worker shall at all times be per- fectly conscious of where the limit is drawn, and how far he may be requested to admit that what is taught is actual truth. That, gentlemen, is the problem which we have to work out in ourselves. The practical questions which are connected with this, lie very near. It is evident that for whatever we consider to be secured scientific truth, we must demand the complete admission, into the scientific treasure of the nation. This the nation must admit as part of itself— xX. must consume and digest it, and continue to work at it. Just in this lies the double promotion which natural science offers to the nation : — On the one hand the material progress, that enormous progress which has been made in modern times. Everything which the steam engine, tele- graphy, photography, chemical discoveries, the research into colours, &c., have produced, all this is essentially based on this — that we, the men of science, complete the doctrines entirely, and when they are perfectly complete and secure, so that we know with certainty that they are natural scientific truths, that we then give them to the nation at large ; then others can work with them as well, and can create new things, of which formerly nobody had any idea, of which nobody dreamt, which come into the world as perfect novelties, and which reform the condition of society and of states. This is the material signifi- cance of our labours. The mental importance, on the other hand, is similar. If I present the nation with a certain scientific truth which is completely proved, to which not the least doubt attaches, if I demand that everybody shall convince himself of the correctness of this truth, that he shall assimilate it, that it shall become part of his thought, then I suppose as a matter of course, that his conception of things generally must be affected by it. Each essentially new truth of this kind must necessarily influence the whole method of conception of man, the method of thinking. If, for instance, to refer to a case in point which lies near, we consider the progress which has been made during recent years with regard to the knowledge of the human eye, beginning at the time when the single component parts of the eye were first anatomically separated, when these single and anatomically separated parts were first examined microscopically and their different arrangement shown, down to the time when we gradually learned to know the vital qualities and the physio- logical functions of the different parts, until at last, by the discovery of the retina-purple (Sehpurpur) and of its photographic properties, a progress was made of which but a year ago we hardly had an idea, then it is evident that with each progressive step of this kind a certain part of optics, particularly the doctrine of vision, is determined and changed. By this we learn in a perfectly certain manner how the action of light takes place in the interior of the human body itself, and that it is quite an outside organ of the human body, not the brain, but the eye which experiences this action. We learn by it that this photo- graphic process is not indeed a mental operation, but a chemi- cal phenomenon, which occurs by the help of certain vital processes, and that in reality we do not see the external things, but their images in our eye. We are thus enabled to gain a new analytical fact for the knowledge of our relations to the world outside of us, and to separate more distinctly the purely mental part of vision from the purely material part. Thus a certain part of optics, and through it one of psychology, is entirely reformed. Chemistry now steps in to investigate questions which up to the present were entirely out of its range, particu- larly the highly important questions. What is retina-purple ? What substance is this ? How is it formed, how decomposed, and how again formed? The solution of these questions will not fail to open an entirely new field for investigation ; let us hope that also on the field of technical photography we shall soon make some progresr., that we shall learn how to produce many-coloured photographs. Thus a mixture of steps of pro- gress is formed, which belong' partly to the material and partly to the mental domain. And I therefore say, that with each true step of progress in natural knowledge a series of changes must necessarily take place in the internal relations of the human race as well as in the external ones, and nobody can prevent new knowledge from influencing him in a certain sense. Each new part of real knowledge works on in man, it produces new con- ceptions, new trains of thought, and nobody can avoid, after all, placing even the highest problems of the mind into a certain relation with natural phenomena. But there is still another side of practical consideration which lies far nearer to us. Everywhere in the entire German Father- land we are now occupied in remodelling educational affairs, in enlarging and developing them, and in determining their precise forms. The new Prussian educational law is on the threshhold of coming events. In all German states larger school-houses are being erected, new institutions are founded, the universities are enlarged, high schools and middle schools are estabhshed. At last the question arises. What is to be the principal tenor of what is taught ? Where shall the school lead to ? In what directions shall it work ? If natural science demands, if we have been exerting ourselves for years to obtain an influence in our schools, if we demand that natural knowledge shall be ad- mitted into education in a much larger measure, so that this fertile material be offered early to the youthful minds, in order to form the basis of a new conception, then we must indeed own that It is high time that we understood one another with regard to what we can and will demand. If Prof. Haeckel says that it is a question for pedagogues whether the theory of descent is now to form the basis of instruction, whether the plasti- dule soul is to be adopted as the basis of all considerations regarding mental phenomena, and whether the phylogeny of man is to be followed up into the lowest classes of the organic empire, and even beyond it up to spontaneous generation, then this is, in my opinion, a mere shifting of tasks. If the theory of descent is as certain as Prof. Haeckel thmks it is, then we must demand its admission into the school, and this demand is a necessary one. How could we imagine that a doctrine of such importance, which influences the conscience of everybody in so revolutionary a manner, which creates directly a soit of new religion, should not be entirely incorporated into the educational plan ! How would it be possible to ignore such a revelation — as I may indeed call it — in our schools, and to kill it by silence as it were, or to leave the transmission of the greatest and most important steps of progress, which our conceptions have made in the whole century, to the option of the pedagogue? Indeed, gentlemen, that would be a resignation of the most severe kind, and in reality it would never be exercised. Every schoolmaster who might receive this doctrine in his mind would teach it as well, even unconsciously. How could he do otherwise? He would have to simulate altogether, he would have to rob himself at times of his own knowledge in the most artificial 74 NATURE [Nov. 22, 1877 manner, in order not to show that he knew and recognised the theory of descent, and that he knew exactly how man has origi- nated and whence he comes. If indeed he did not know where man goes to, yet he would at least believe that he knew for certain how in the course of aeons the progressive series shaped itself. Therefore I say that if we really did not demand the admission of the theory of descent into the educational plan, this would yet be accomplished of its own accord. We certainly should not forget, gentlemen, that what here we express, perhaps still with a certain timid reserve, is propagated by those outside with a confidence increased a thousand-fold. For instance, I have once pronounced the phrase — in opposition to the doctrine then reigning of the development of organic life from inorganic matter— that each cell had its origin in another cell, indeed at that time with special reference to pathology, and principally with regard to man himself. I may remark here that in both relations I still to-day consider this phrase a perfectly correct one. But when I had pronounced this doctrine and had formulated the origin of the cell from the cell, others were not wanting who extended this phrase not only in the organic world far beyond the limits for which I had intended it, but who put it down as generally valid even beyond the limits of organic life. I have received the most wonderful communications both from America and Europe, in which the whole of astronomy and geology were based upon the cellular theory, because it was thought impossible that something which was decisive for the life of organic nature upon this earth should not be equally applied to the heavenly bodies, v^^hich virere said to be round bodies after all, and which had shaped themselves into globes and represented so many cells flying about ia universal space and playing a part there similar to that of the cells in our body. I cannot say that the authors of these communications were all decided fools and simpletons ; on the contrary, from some of their explanations I gained the idea that many an other- wise educated man, who had studied much and finally attacked the problems of astronomy, could not understand that the utility of heavenly phenomena should be based upon something else than the utility of human organisation, so that he, in order to gain a monistic conception eventually arrived at the supposition that the heaven must also be an organism, that indeed the whole world must be an organism of useful arrangement, and that no other principle but that of the cells could apply to it. I cite this only in order to show what shape things take outside, how " theories " are enlarged, and how our own doctrines may return to us in a form fearful to ourselves. Now only imagine how the theory of descent may be shaped to-day in the head of a socialist ! Indeed, gentlemen, this may seem ridiculous to many, but it is very rerious, and I only hope that the theory of descent may not bring all those horrors in our country which similar theories have actually brought to our neighbours. Anyhow this theory, if carried through to its consequences, has an extremely dangerous side and that the socialists have a certain notion of it already, you will doubtless have remarked. We must make this quite clear to ourselves. Nevertheless the matter might be as dangerous as possible, the confederates might be as bad as they could be, and yet I say, from the moment when we are convinced that the theory of descent is a doctrine perfectly proved, so certain that we could swear by it, that we could say, thus it is, — from that moment we must not hesitate to introduce it into general life, transmit it not only to every educated person, but teach it to every child, make it the basis of our whole conception of the universe, of society, and of the state, and found our educational system upon it. This I consider a necessity. In saying this I am not at all afraid of the reproach, which to my astonishment has made a great noise in my Prussian Father- land, while I was absent in Russia, I mean the reproach of half- kmivledge. Strange to say, it was one of our so-called liberal journals which asked the question whether the great faults of our time, and socialism in particular, were not based upon the diffu- sion of half-knowledge. With reference to this I would like to state here, in the midst of the Naturalists' meeting, that all human knowledge is only piece-work. All of us who call ourselves naturalists, only possess pieces of natural science ; none of us is able to come here and represent each science with the same right, or participate in the discussions of any scientific section. On the contrary, ic is just because they have developed themselves in a certain one-sided direction, that we esteem the special scientific men so highly. On the other fields we are all in half-knowledge as it were. Oh ! that we could only succeed in diffusing this half-kno.vledge moro and more, if we could succeed in causing at least the majority of educated persons to progress far enough to be able to survey the principal directions which the single depart- ments of natural science are taking, and to follow their develop- ment without meeting difficalties toa great to be overcome, so that they would at least be aware of the general progress of science, if, indeed, they were not acquainted, at every moment, with the totality of all single and special proofs. We do not get much further ourselves. I, for instance, have honestly tried during my time of life to obtain chemical knowledge ; I have even worked ia a laboratory, but I feel thoroughly incompetent to sit down at soma chemical meeting without preparation, and to discuss modern chemistry in all directions. Nevertheless I am able to penetrate, after a time, so far into any chemical novelty that it does not strike me as incomprehensible. But I must always first acquire this understanding, I have not got it to start with ; and when I want it again I must acquire it again. That which honours me is the knowledge of my ignorance. The most important part is that I know perfectly well what I do not know of chemistry. If I did not know that then of course I should always be wavering to and fro. But as I imagine that I am tolerably well aware what I do not know, I say to myself every time I am obliged to enter a domain which is stdl closed to me : " Now I must begin again to learn, now I must study afresh, now I must do as anybody does who enters the domain of science." The great error, which is equally shared by many educated people, consists in not remembering that with the enormous extent of natural science and with the inexhaustible quantity of detailed material, it is i.-npossible for any single person alive to cooimand the totality of all these details. That we get far enough to kno w the yyw/^i:/^//^/;^ of natural science and the gaps which exist in our own knowledge, so that every time we find a gap of this kind we say to ourselves, — " Now you enter a domain which is unknown to you," — that is what we must arrive at. If everybody was only sufficiently aware of this, many a one would beat his breast and own that it is a dangerous thing to draw general conclusions with regard to the history of all things when one is not even entirely master of the material from which these conclusions are to be drawn. {To be continued.) UNIVERSITY AND EDUCATIONAL INTELLIGENCE Cambridge. — This term has witnessed the election of two new Natural Science fellows. Mr. A. M. Marshall, Senior in the Tripos of 1874, has been elected at his own College, St. John's. His able papers on Embryology have been an im- portant addition to the researches which are making the British school again famous in this subject, and he is the first Doctor of Science in Comparative Anatomy in the University of London. Two of the newly-elected fellows of St. John's are taking to Medicine, viz.. Dr. Marshall and Mr, McAlister, the last Senior Wrangler. At Trinity the open fellowship has been adjudged for the first time to a non-member of the College, Mr. J. N. Langley, B. A., of St. John's, whose services as Demonstrator of Physiology to Dr. Foster are most highly appreciated, while his originality and perseverance in research will, before long, be much more widely known than at present. I understand that the aid of Piof Huxley was called in, giving the highest guarantee to the examination in Biology, and that several candidates showed themselves in every way worthy of a fellowship, especially in the original memoirs which were sent in before the examination. The new buildings for anatomy and physiology are advancing to completion and are partially occupied, Mr. Bilfour's two prac- tical courses of Comparative Anatomy being accommodated in them. Dr. Foster will transfer much of his work here after Christmas. The new buildings will be almost too small as soon as completed, for Dr. Foster has fifty men and several ladies working in his elementary classes this term, a very large number when it is considered that this is voluntary and not prescribed work. It is but a just tribute to Dr. Foster's rare value as a teacher who makes his students think, who sacrifices his time most indefatigably for their interests, and who cultivates the powers of investigation developing in his pupils with all the care of a paren^. Instead of engrossing authority to him- self, he sets his senior pupils to lecture on the subjects they make a special study ; thus during the present winter the advanced class will receive lectures from Dr, Gaskell, Mr. Langley, and Mr. Lea. Mr, Vines has returned from working in Germany Nov. 22, 1877] NATURE 11 with Sachs, and is lecturing toa' large ctass'^n Vegetable Phy- siology. Next year he will start the first practical course of botany, and, being unable to induce his college to provide appa- ratus for a laboratory, intends to furnish it at his own expense. Among other lectures in natural science Prof, Dewar's on Physical Chemistry are taking high rank. It is to be noted that Mr. Apjohn, the late lamented Praslector of Chemistry at Caius College, was to have received a fellowship this term by special vote of the whole of the fellows. The praelectorship is to be continued nr.ostly in its old form, but it is worthy of note that the prosecutinn of original research is put prominently among the duties <-f the office, as well as the instruction of students from the University generally. There are nearly a score of candidates, including such well-known names as Mr. W. Noel Hartley, Dr. J. T. Bottomley, and Dr. Dittmar. Prof. Clerk Maxwell greatly interested the Philosophical Society at its last meeting by an account of Henry Cavendish's unpublished writings and experiments on electricity. He was not generally known to have done much electrical work, and his papers were long in the hands of Sir W. Snow Harris, who is declared by Prof. Maxwell, after careful examination, to have made no use of Cavendish's work without full and adequate acknowledgment. These writings are left in a form quite iitted for publication, and will greatly advance the reputation of the great philosopher. His exactness, his candour, his grasp of the subject, his notable achievements with the small variety of instru- ments available in his time, were fully sliown by the examples cited to the Society. Yet these were less than his remarkable insight into electrical laws, his correct conception of potential, his ideas of investigating the total charges of bodies, and the resistance of electrolytes. Prof. Maxwell thought that nobody had ever possessed so large and various a collection of condensers of known capacity as Cavendish, but his family taciturnity pre- vented his merits from being fully known. He trained himself to be his own galvanometer, and the general value of his results is remarkable when compared with those obtained by modem iristruments. In regard to university reform, it appears that in some colleges at least there is a danger of the non-resident fellows, who form the largest proportion of the governing body under the act, endea- vouring to maintain at a very high number the fellowships to which no duties are attached ; of course every such fellowship diminishes the funds available for definite association with the progress of research and education. Some men hold very strongly to the " start in life" theory of fellowships ; viz., that they ought to receive three hundred a year for 'a number of years in order that they may gain three thousand a year in a profession the more speedily. Glasgow^. — Mr. Gladstone has been elected Lord Rector of Glasgow University in succession to the Earl of Beaconsfield. Berlin. — The well-known botanist, Prof. Sachs, of Wiirz- burg, has received a very flattering call to Berlin. Neither pains nor money seem to be spared by the Prussian Government in attracting to the capital the foremost talent of Germany ; and certainly in this choice of a successor to Alexander Braun no change of policy is shown. GoTTiNGEN. — The sum of 5o,cx30 marks has recently been appropriated for the erection of a phyto-physiological institute in the Botanical Gardens. GiESSEN. — In consequence of the late discussions excited by Prof. M( mmsen's articles on the Ph.D. examinations in Ger- many, the University of Giessen has issued an announcement stating that for the future no faculty can bestow the title of Doctor, except on the basis of a thesis and oral examination. DoRPAT. — The winter attendance at the university is 853, of whom but seven are non-Russian. Brunswick. — On October 16 interesting ceremonies took place at the opening of the magnificent new buildings of the Carolo-Wilhelminum Polytechnic, in which representatives 'of the Government, and delegates from all the great German poly- technics, took part. The new edifices are of great extend, and richly equipped with all possible adjuncts for modern technical education, so that this well-known institution will be able to maintain its well-earned reputation. The Carolo-Wilhelminum is the oldest polytechnic in Germany, having been founded in 1745, and the list of its students embraces many distinguished names, such as Gauss, the mathematician, Christopher Codring- ton, the' English commander at the naval victory of Navarino, &c. SOCIETIES AND ACADEMIES London Chemical Society, November 15.— Dr. Gladstone in the chair. — The following communications were made :— First report to the Chemical Society on some points in chemical dynamics, by Dr. Wright and Mr. Luff. An elaborate series of experi- ments was made to find out the temperatures at which the actions of ciarbonic oxide, hydrogen, and free amorphous carbon on oxide of iron or oxide of copper are first perceptible. The authors find that this temperature varies with the physical con- dition of the oxide used, that hydrogen acts, on a given ox'de, at a lower temperature than carbon and carbonic oxide, at a lower temperature than hydrogen, and that a given reducing agent begins to act on copper oxide at a lower temperature than on iron oxide. — On the chemistry of cocoa butter, Part I. ; two new fatty acids, by C. T. Kingzett. The first acid is a low acid of the series, C,jll2„02, having the formula CjaHo^Oj, i.e., lauric acid, but it melts at 57° '5. The second acid "is a high acid having the formula ^i^S^xi^O^, crystallising in microscopic needles or granules, melts at ']2^'2, and at a high temperature distils apparently unchanged. The author proposes for it the name of theobromic acid. It is pointed out that the usual state- ment in books, "that cocoa butter yields almost exclusively stearic acid " is entirely incorrect. — The third paper was on the influence exerted by time and mass on certain reactions in which insoluble salts are produced, by Mr. M. P. Muir. The author has taken solutions containing known quantities of calcium chloride and potassium or sodium carbonate mixed, allowed to stand for a certain number of minutes, and then estimated the quantity of calcium carbonate formed. He has arrived at the following conclusions : — That the greater portion of the chemxal change takes plice during the first five minutes ; the reaction then decreases in rapidity. The relative masses of the salts exert an important influence. Thus if the mass of alkaline carbonate be four times that required, the action is completed in five minutes, but if an equivalent quaniity only be present the action is not finished in forty-six hours. Potassium carbonate yields more calcium carbonate in a given time than sodium carbonate. An increase of temperature increases, whilst dilution, especially with solutions of potassium or sodium chloride, diminishes the rapidity of the action. Some experiments are given on the action of solutions of calcium sulphate and sodium chloride. Entomological Society, November 7. — Prof. Westwood, president, in the chair. — Mr. McLachlan exhibited ten of the thirteen species of Lepidoptera collected by Capt Feilden and Mr. Hart in Grinnell Land, between 78° and %i° N. lat, during the recent Arctic Expedition, and made some remarks upon the general insects of the Arctic Regions. — The Rev. A. Eaton also made some observations upon the same subject. — Mr. Meldo'a exhibited a five-winged specimen of Gonepteryx rhamtii, taken in Norfolk by Mr, John Woodgate ; likewise a gynandromorphic specimen oi Fieris brassicce, caught in Oxfordshire by Mr. J. B. Watson. The right half of the latter insect was female and the left half male. — Mr. H. Goss exhibited a gynandromorphic speci- men of G. rhamni, captured in Sussex ; in this insect also the right side was female and the left side male. — Mr. J. W. Douglas exhibited a specimen oi Polyphylla fullo, Linn., which had flown on to a steamer at Antwerp, and been thus brought to this country. Mr. Douglas also exhibited a specimen of the rare Telttgomelra impreisopunctata and one of Typhlocyba dcbilis, both taken on Sanderstead Downs ; and likewise, for comparison, an example of T. tenerrima. — Mr W. C. Boyd exhibited a larva of Pi^ris rapes attacked by Aficrogaster. — The president read notes on exotic Coleoptera, and exhibited specimens of Calo- metopus Nyassce, Afnblyodus Nicaragtice and drawings of other species. — Prof. Westwood also remarked upon an Indian Mantis {Gongylus gongylodes) which had been recently described by Dr. Anderson in the Proceedings of the Asiatic Society of Bengal for August, 1877, as being a simulator of a flower to a remarkable degree of perfection. — Mr. Wood- Mason also made remarks upon the same subject and upon stridulating organs in cnistaceans with reference to a letter on this suljject by Mr. Saville Kent in this journal (vol. xvii. p. Ii). Mr. Wood-Mason hkewise announced the discovery of a stridulating apparatus in a Phasma. — Sir Sydney Saunders read a note on the specific identity of the Hampstead Atypus, Mr. F. Enoch exhibited and made re- marks upon a male and female of this spider. — The following piapers were read : — Descriptions of new species of the colcop* IM- MATURE [Nov. 22, 1877 terous genus, Callirhipis {Rkipidoceridai), in the British Museum, by C. O. Waterhouse. — Descriptions of a new genus and two new species of Sphingida:, with remarks on the family generally, by A. G. Butler. — Descriptions of Halticince, by J. S, Baly. — Descriptions of new species of Clerida, with notes on the genera and corrections of synonymy, by the Rev. H. S, Gorham. Royal Astronomical Society, November 9. — Dr. Hugglns, F.R.S., in the chair. — A very large number of papers were presented. — Lord Lindsay was called upon to read Mr. Gill's report upon the expedition to Ascension to obtain the parallax of Mars, from which it appeared that in spite of meteorological difficulties and many causes of anxiety most satisfactory results had been obtained, and Mr. Gill had gone up a mountain to recruit his health. — Several important mathematical papers were then read ; one by the Astronomer- Royal on the solar parallax, as deduced from telescopic observations of the transit of Venus, 1874. — Next a paper by Prof. Adams on the motion of the moon's node, and a paper by Mr. Neison on three small inequalities in the mean motion of the earth, and a small inequality in the mean motion of Mars. These were followed by three observational papers on the recent opposition of Mars ; one by the Astronomer-Royal, read by Mr. Christie, giving the summary of what was seen at Greenwich both with the telescope and spectroscope ; the next by Mr. N. £. Green, giving an account of his expedition to Madeira and what he saw of Mars with a fine 13 inch reflector. This paper was accompanied by a series of beautiful drawings of the planet by the author. The third paper, on Mars, was by Mr. John Brett, being a discussion of a series of telescopic observations made in Cornwall, the purport of which was to show that the generally received hypo- thesis of the physical condition of Mars was altogether fallacious, neither the snows nor the seas having any foundation in fact. This paper was also illustrated by a series of drawings. — Then followed a y aper by Lord Lindsay, on a new form of spectro- scope, and the meeting adjourned. Anthropological Institute, November 13. — Dr. John Evans, r.R.S., president, in the chair. — The Rev. T. A. Bennett and F. V. Dickins were elected members. — An interesting series of casts of skulls made of papier-mache were exhibited, and a special vote of thanks was ordered to be sent to Prof. Bogdanow, of Moscow, by whom they were presented to the Institute. — Major-Gen. A. Lane Fox, F.R.S., exhibited some flint flakes from Egypt, and a note from Capt. R. F. Burton was read on the same. — The director then read a paper by Mr. H. H. Howorth, F.S A , on the spread of the Slaves: Part I., the Croats. —This was followed by a paper on the Castiheri d'Istria, by Capt. R. F. Burton, H.M.'s Consul at Trieste.— Mr. Hyde Clarke, the President, Major-Gen. A. Lane Fox, and Mr. Moggridge took part in the discussions. Institution of Civil Engineers, November 13. — Mr. George Robert Stephenson, president, in the chair. — Ihe paper read was a review of the progress of steam shipping during the last quarter of a century, by Mr. Alfred Holt, M. Inst. C.E., of Liverpool. Paris Academy of Sciences, November 12. — M. Peligot in the chair. — M. Faye presented the volume of the Connaissance des Temps for 1879. — On some applications of elliptic functions (con- tinued), by M. Hermite. — Resume oi a history of matter (fourth article) by M. Chevreul. This relates to the views of Lavoisier, Stahl, Scheele, Cavendish, and Priestley. — Observations on the principle of maximum work and on the spontaneous decomposition of hydrated bioxide of barium, by M. Berthelot.— On the hmits of etherification, by M. Berthelot. In experimenting en etheri- fication sixteen years ago he put aside a number of mixtures to be kept a considerable time, in order to ascertain the limit of the reactions produced at ordinary temperatures. The mixtures consisted of acetic acid and alcohol (equal equivalents), acetic acid and glycerine, tartaric acid and alcohol, valeric acid and alcohol. He has now examined these. The general laws of eiherification are confirmed, and especially the identity of the limits of combinations betw^een acids and alcohols, from ordinary temperatures up to 260°. — On the order of appearance of the first vessels in the shoots of some Legumlnosse (second part), by M. Trecul. — The Academy elected a commission to present a list of candidates for the vacancy among the Foreign Associates, caused by the death of M. von Baer. — On the numeration of globules of milk for the analysis of woinan's milk, by M. Bouchut. A drop of milk is mixed with 100 drops of slightly saline water (distilled). A drop of the mixture is placed under the microscope, whose eye-piece is divided into squares ; the number of globules in each square is counted, and the average taken ; from this may be deduced the number in one cubic millimetri>. The globules were thus counted in milk of 158 nuises, before, during, and after suckling. The average of globules is about l,026,cxx) per cubic millimetre of milk, or a hundred and two milliards six hundred millions per litre ; but between 800, cxx> and one million per cubic millimetre, the milk is considered of good quality. In one table are given the density and the quantity of butter corresponding to given numbers of globules of cow's milk. — New formulae for the study of the motion of a plane figure, by M. Haton de la Goupilliere. — On the migration of the puceron of the cornel tree and its reproduction, by M. Lichtenstein. This puceron comes from the roots of gramineae, and returns to them. Its mode of reproduction is that termed by the author anthogenesis. — Observations on the subject of a recent communication from M. Fabre, by M. Millardet. The secretary announced a new biennial prize, founded by M. Maujean. — Discovery of a small planet at the Observatory of Paris, by M. Paul Henry. — Discovery of a small planet at the Observatory of Pola, by M. Palisa. —Observations of planets 125 and 176 made at the Paris Observatory (equatorial of the garden), by MM. Paul and Prosper Henry. — New stellar systems, by M. Flam- marion. — On the equation with partial derivatives of the third order expressing that the problem of geodesic lines, considered as a problem of mechanics, supposes an algebraic integral of the third degree, by M. Levy. — On the evolution of red corpuscles in the blood of oviparous vertebrates, by M. Hayem. The red corpuscles proceed from a peculiar colourless element, which from the first phases of development is distinct from the white corpuscles ; the name of hematoblast is given it. The white corpuscles are foreign to the formation of the red, both in oviparous vertebrates and in the higher animals ; but whereas in the latter the red corpuscles of new formation are coloured, what- ever their minuteness, in the oviparous, the embryonic cor- puscles are at first quite without haemoglobin. — On the spots and crevices of pears, by M. Prillieux. These are due to the growth of a small parasitic champignon. — On the semi-diurnal variations of the barometer, by M. De Parville. He thinks it improbable that aqueous vapour has a preponderating influence in these variations. — On the quantities ot heat liberated in mix- tures of sulphuric .icid anl water, by M. Maumene. Sulphuric acid recently heated does not liberate, with water, the same quantity of heat as the same acid kept several months. This phenomenon, denoted as a tempering of liquids, seems to him a source of error in researches on thermo-ctiemistry not hitherto considered. CONTENTS Pagk Danish Greenland 57 Our Book Shklf : — Harrison's " Sketch of the Geology of Leicestershire and Rutland " 58 Letters to the Editor : — Expected High Tides —Edward Roberts 58 Rainiall in the J'emoerate Zone in Connection with the Sun-spot Cycle. — Dr W. W Hunter "jg Contribution to the Sun-spot Theory of Rainfall. — Dr. E Bonavia 6r The Radiometer and its Lessons — Prof Osbornb Reynolds ; Dr. WiLLiAJi B. Carpenter, F R.S. . 61 Fluid Films —C. ToMn^sov, F.R S 62 Tuckey and Stanley. — The Yallala Rapids on the Congo — Dr. J. Rae 62 The Future of our British Flora.— A Craig-Christie .... 62 Selective Discrimination of Insects. — Henry O Forbes .... 62 Ths Earth-worm in Relation to the Fertility of the Soil. — Geo. H. Phipps 62 Smell and Hearing in Moths — E. H K 62 Carnivorous Plants. — Francisco Ginkz 63 Our Astronomical Column : — Minor Planets di The Comet of 1672 63 Mr. Darwin at Cambridge 64 International Geological Congress 65 The Modern Telescope. By J. Norman Lockyer, F.R.S. {.With Illustrations) • 66 Zoological Gardens 63 Notes 69 The Liberty of Science in the Modern State. By Prof Rudolf ViRCHow 72 University and Educational Intelligence 74 Societies AND Academies 75 NA TURE 17 THURSDAY, NOVEMBER 29, 1877 FLORA OF MAURITIUS AND SEYCHELLES Flora of Mauritius and the Seychelles : a Description of the Flowering Plants and Fer7is of those Islands. By J. G. Baker, F.L.S. (London : L. Reeve and Co., 1877.) THIS compact volume of nearly 6go pages, adds another to the already long list of colonial floras prepared at Kew and issued under the authority and at the expense of the Colonial Government. It is arranged on the same plan as the other floras, many of them so well known, giving first, some general remarks on the physical geography and botany of the islands, and then that admirable outline of elementary botany prepared by Mr. Bentham, and which contains every definition necessary in descriptive botany, thus enabling the student to follow the technical descriptions given in the " Flora " itself. The work is almost entirely from the pen of Mr. J, G. Baker (the Orchids being by Mr. Le Marchant Moore, and the Palms and Pandani by Dr. I. B. Balfour), and is only another example of the indomitable industry so characteristic of Mr. Baker. The materials at the disposal of the author have been ample, and probably there is but little left to discover in Mauritius, the Seychelles, and Rodriguez, although many forms have not as yet been fully determined owing to the want of perfect specimens. Hence it is desirable that naturalists visiting the islands should endeavour to complete our knowledge of these imperfectly known plants. The smaller dependencies of Mauritius have not been explored botanically, hence there is probably a rich field for the investigator of these numerous islands. It is, moreover, all the more desirable to have these islands explored as the native flora of the islands already known has been completely altered by the introduction of cultivated plants and weeds as well as by the destruction of the native forests. Thus it is probable that in some of the undisturbed islands a rich native flora may be met with, or that some of the forms either rare or extinct on other islands, may yet be comparatively abundant. Mauritius is about 39 miles by 35, and has an area of 700 square miles, or a little smaller than the County of Surrey. It is situated at a distance of about 500 miles from Madagascar and 100 miles from Bourbon, and is just within the Tropic of Capricorn. The northern part of the island is a low plain covered with sugar plantations. In the centre is an elevated plateau rising to about 1,500 feet above the sea- level, the great mass of the rocks being entrely volcanic. Outside the central plateau, and within a short distance of the sea, rise the three principal moun- tain ranges, the highest portions being from 1,900 to 2,900 feet in height. There are two small lakes in the central plateau, the Grand Bassin and the Mare aux Vacoas. There are six rivers, about ten to twelve miles in length, and numerous small rivulets. The climate is warm, and at Poit Louis the mean annual temperature is 78° F. As a result, the vegetation has a decidedly tropical character. There are however, a few south temperate plants present, and also a number of the widely-spread temperate forms, as Nephrodt2imfilix-mas^ Cardamine hirsuta, Juncus effusus, Convolvulus arvensis, Plantago majory and P. lanceolata. Vol. XVII.— No. 422 Sugar is extensively cultivated in Mauritius. The increase in the cultivation "of sugar has led to the destruction of the forests, which at one time covered the island to the water's edge. As a result of the destruction of the forests, the indigenous flora has almost become destroyed. The orchids, ferns, pandani, and the shade-loving plants, and the curious endemic trees and shrubs have, within 100 years, been either entirely exterminated, or else have become exceedingly rare and local. The native vegeta- tion thus partly exterminated has been replaced by a number of introduced trees, shrubs, and weeds, to an extent only exceeded by the destruction of the indigenous flora of St. Helena. There seem to be about 269 intro- duced plants in Mauritius, and 869 undoubted native species, making a total flora of about 1,138. The Seychelles are situated 900 miles nonh-east of Mauritius, in 3°-6° south latitude, and consist of a group of about thirty islands, most of them of very small size. The islands are entirely granitic. The largest of the group, Mahd, has an area of 30^000 acres ; the best culti- tivated and most populous is La Digue, with an area of 2,000 acres. The mountains range from about 1,500 to 3,000 feet in height. The seasons are similar to those of Mauritius. Cotton was at onetime extensively cultivated, and the aboriginal forests were destroyed to make room for cotton plantations. Now cotton is hardly cultivated, the chief exports from the island being cocoa-nut oil and fibre. The vegetation is wholly tropical ; the few tempe- rate species found in Mauritius being absent from the Seychelles. The number of flowering plants and ferns from these islands is 338. Five genera of palms and one genus of Ternstroemiacese are endemic. The endemic palms are mostly well known, and belong to the genera Deckenia, Nephrosperma, Roscheria, Verschaffeltia, Lodoicea, and Stevensonia, The total number of endemic species is sixty. The rest of the flora consists chiefly (250) of widely distributed tropical plants, and be- tween twenty and thirty are of characteristic Mascarene types. The flora was expected to have been much richer in endemic forms from the isolated position and peculiar geological construction of the islands than^it has proved to be after the most careful examination. Rodriguez is situated 300 miles to the north and east of Mauritius, and is an island about eleven miles by five, with the hills in the interior reaching an elevation of little over 1,000 feet. The rock is entirely volcanic, and the climate similar to that of Mauritius. The flora must have undergone great changes, as the earliest records of the island state that it was entirely wooded. The plants of the island number about 202 wild flowering plants and ferns, nearly all collected, ^by that rising young botanist, Dr. I. B, Balfour, one of the staff of the Transit of Venus Expedition to Rodriguez. Of the 202 wild species, thirty- six are peculiar to the island j and there are three endemic monotypic genera, one Mathurina having been discovered and described by Dr. I, B, Balfour. The total number of species as given by Baker may be thus summarised : — There are 1,058 native species in the " Flora," 869 natives of Mauritius, 338 natives of Sey- chelles, and 202 native in Rodriguez ; 269 are naturalised in these islands, thus giving a total number of 1,327 species included in the " Flora of Mauritius and the Seychelles." The distribution of the species in the flora 7^ NATURE [Nov. 29, 1877 is also interesting. Thus there are 304 endemic species, 232 Mascarene species, i.e., plants confined to Bourbon, Mauritius, Madagascai-, and the Comoros ; 66 African but not Asian, 86 Asian but not African ; 145 common to Asia and Africa ; and 225 common to the Old and New World. If we take the percentages we have the following results :— 29 per cent, endemic, 22 per cent. Mascarene, 21 per cent, common to the Old and New World, 14 per cent, common to Asia and Africa, 8 per cent. Asian but not African, and 6 per cent. African but not Asian. From this it is evident that one-half of the wild plants of the flora are restricted to the Mascarene Archipelago. The orders containing the greatest number of species are the following : — Orchidacece, 79 ; Gramine^e, 69 ; CyperaceiE, 62 ; Rubiaceae, 57 ; Euphorbiaceas, 45 ; CompositJe, 43 ; Leguminosse, 41 ; Myrtacese, 20. There also 168 species of Filices, but it is rather unfair to con- sider the Filices as an order equivalent say to the Euphorbiaceas or Myrtaceee in the above enumeration. The descriptive part of the flora is elaborated in the same manner as the colonial floras already published, and is, as already mentioned, almost entirely the work of Mr. Baker, with the exception of the Orchids, Palms, and Pandani. Any one acquainted with Mr. Baker's work will know that any detailed notice of the descriptive part of the present volume is superfluous. W. R. McNab OUR BOOK SHELF Die Geologie. Franz Ritter von Hau^r. (Vienna : A Holder, 1877.) It is a good sign both of the progress of geological study in Austria and of the value of this manual by the director of the Austrian Geological Survey, that a second edition of the work has been called for within three years of the date of its publication. A sample of the revised issue which has been sent to us fully bears out the description on its title-page that it is enlarged and improved. The original work, besides its clearly-expressed introductory chapters on general dynamical and mineralogical geology, is especially a valuable repertory of information regarding the structure and palaeontology of the Austro- Hungarian monarchy. In the new edition, Ritter von Hauer is evi- dently doing his best to keep his manual abreast of the time. The book is well-printed, but the author is still in the hands of a very poor wood-engraver. The new cuts are as rude and feeble as ever. _ ^, .., , — — — . , '. i £fi,ifj[ a^..; LETTERS TO THE EDITOR \The Editor does not Jiold himself responsible for opinions expressed by his correspondents. Neither can he tmdertake to return, or to correspond with the writers of, rejected manuscripts. No notice is taken of anonymous communuations. The Editor urgently requests correspondents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of com- munications containing interesting and novel facts.'} Fritz Muller on Flowers and Insects The enclosed letter from that excellent observer, Fritz Miiller, contains some miscellaneous^ observations on certain plants and insects of South Brazil, which are so new and curious that they will probably interest your naturalist readers. With respect to his case of bees getting their abdomens dusted with pollen while gnawing the glands on the calyx of one of the Malpighiacese, and thus effecting the cross-fertilisation of the flowers, I will remark that this case is closely analogous to that of Coronilla recorded by Mr. Farrer in your journal some years ago, in which parts of the flowers have been greatly modified, so that bees may act as fertilisers while sucking the secretion on the outside of the calyx. The case is interesting in another way. My son Francis has shown that the food-bodies of the Ball's-horn Acacia, which are consumed by the ants that protect the tree from its enemies (as desciibed by Mr. Belt), consist of modified glands ; and he suggests that aboriginally the ants licked a secretion from the glands, but that at a subsequent period the glands were rendered more nutritious and attractive by the retention of the secretion and other changes, and that they were then devoured by the ants. But ray son could advance no case of glands being thus gnawed or devoured by insects, and here we have an example. With respect to Solatium palinacanthum, which bears , two kinds of flowers on the same plant, one with a long style and large stigma, the other with a short style and small stigma, I think more evidence is requisite before this species can be con- sidered as truly heterostyled, for I find that the pollen-grains from the two forms do not differ in diameter. Theoretically it would be a great anomaly if flowers on the same plant were functionally heterostyled, for this structure is evidently adapted to insure the cross-fertilisation of distinct plants. Is it not more probable that the case is merely one of the same plant bearing male flowers through partial abortion, together with the original hermaphrodite flowers ? Fritz Miiller justly expresses surprise at Mr. Leggett's suspicion that the difference in length of the jpistil in the flowers of Pontederia cordata of the United States is due to difference of age ; but since the publication of my book Mr. Leggett has fully admitted, in the Bulletin of the Torrey Botanical Club, that this species is truly heterostyled and trimorphic. The last point on which I wish to remark is the difference between the males and females of certain butterflies in the neuratioa of the wings, and in the presence of tufts of peculiarly-formed scales. An American naturalist has recently advanced this case as one that cannot possibly be accounted for by sexual selection. Consequently, Fritz Miiller's observations which have been published in full in a recent number of Kosmos, are to me highly interesting, and in themselves highly remark- able. Charles Darwin Down, Beckenham, Kent, November 21 You mention (" Different Forms of Flowers," page 331), the deficiency of glands on the calyx of the cleistogamic flowers ot several Malpighiacese, suggesting, in accordance with Kerner's views, that this deficiency may be accounted for by the cleisto- gamic flowers not requiring any protection from crawling insects. Now I have some doubt whether the glands of the calyx of the Malpighiacese serve at all as a protection. At least, in the one species, the fertilisation of which I have very often witnessed, they do not. This species, Bunchosia gaudichaudiana, is regu. larly visited by several bees belonging to the genera Tetrapedia and Epicharis. These bees sit down on the flowers gnawing the glands on the outside of the calyx, and in doing so the under side of their body is dusted with pollen, by which, afterwards, other flowers are fertilised. There are here some species of Solanum (for instance S, palina' canthum) bearing on the same plant long-styled and short-styled flowers. The short-styled have papillce on the stigma and appa- rently normal ovules in the ovary, but notwithstanding they are male in function, for they are exclusively visited by pollen-gather- ing bees (Melipona, Euglossa, Augochlora, Megacilissa, Eophila, n. g., and others), and these would probably never insert their proboscis between the stamens. In a few months I hope to be able to send you seeds of our white-flowered violet with subterranean cleistogamic flowers. I was surprised at finding that on the Serra (about i, 100 metres above the sea) this violet produced abundant normal fruits as well 35 subterranean ones, while at the foot of the Serra, though ISIov. 29, 1877] NATURE 79 it had flowered profusely, I could not find a single normal fruit, and subterranean ones were extremely scarce. Acccording to Delpino the changing colours of certain flowers would serve to show to the visiting insects the proper moment for effecting the fertilisation of these flowers. ; We have here a I.antana the flowers of which last three days, being yellow on the first, orange on the second, purple on the third day. This plant is visited by various butterflies. As far as I have seen the purple flowers are never touched. Some species inserted their proboscis both into yellow and into orange flowers {Danais erippus, PUris arlpa), others, as far as I have hitherto observed, exclusively into the yellow flowers of the first day {Ilelicouius apsiudes, Colanh jii'ia, Eurema leuce. This'is, I think, a rather interesting case. If the flowers fell off at the end of the first day the inflorv'jscence would be much less conspicuous ; if they did not change their colour much time would be lost by the butterflies: inserting their proboscis in already fertilised flowers. In another Lantana the flowers have the colour of lilac, the entrance of the tube is yellow surrounded by a white circle ; these yellow and white markings disappear on the second day. Mr. Leggett's statements about Pontederia cordata appear to me rather strange, and I fear that there is some mistake. In all the five species of the family which I know the flowers are so short- lived, lasting only one day, that a change in the length of the style is not very probable. In the long-styled form of our high- and Pontederia the style has its full length long before the flowers open. In my garden this Pontedaria is visited by some species of Augochlora collecting the pollen of the longest and mid-length stamens ; they are too large to enter the tube of the corolla, and have too short a proboscis to reach the honey ; they can only fer- tilise the long-styled and mid-styled forms, but not the short- styled. Among the secondary sexual characters of insects the meaning of which is not understood, you mention ("Descent of Man," vol. i., p. 345) the different neuration in the wings of the two sexes of some butterflies. In all the cases which I know this difference in neuration is connected with, and probably caused by, the deve- lopment in the males of spots of peculiarly-formed scales, pencils, or other contrivances which exhale odours, agreeable no doubt to their female?. This is the case in the genera Mechanitis, Dircenna, in some species of Thecla, &c. Fritz Muller Blumenau, St. Catharina, Brazil, October 19 The Radiometer and its Lessons Prof. Osijorne Reynolds's letter in Nature (vol. xvii. p. 26) has directed attention prominently to the circumstance that two hypotheses have been submitted to the scientific world as explanations of the force and motions which Mr. Crookes had shown to exist— one by Prof. Osborne Reynolds, the other by myself. Prof. Osborne Reynolds's explanation is based on the fact that when a disc with vertical sides is heated on one side and exposed to a gas, a convection current sets in, which' draws a continuous supply of cold gas into contact with the hot surface of the disc. As this cold gas reaches the disc it is expanded, and thus its centre of gravity is thrown-further from the disc. Accordingly, the disc, it freely suspended, will move in the opposite direction so as to keep the centre of gravity of the gas and disc in tlie same vertical line as before, and, if not freely suspended, will suffer a pressure tending to make it move in that direction. If I have understood Prof. Reynolds aright, this is both a correct and full description of his explanation as last presented. My explanation, on the other hand, is based on tnolecular motions which go on in the gas without causing any molar motion, and is independent of convection currents. Prof, Rey- nolds is therefore, I conceive, fully justified in denying that my theory has supplied any deficiency in his explanation. As he points out, the two explanations are incompatible ; if either is correct, the other is wholly wrong. It is easy to apply comparative tests to the lival hypotheses by making a selection from Mr. Crookes's incomparable experi- ments, from the experiments by Mr. Moss and myself, and from instances of compressed Crookes's layers in the open atmosphere ; but it is not easy to make the choice so as to bring the abundant evidence within the compass of a letter. These tests might take various forms, of which perhaps the most direct is to ascertain whether the force is affected by varia- tions in the convection current, as required by Prof. Reynolds's hypothesis, or is independent of convection, but increased when the heater and copier are brought nearer together, as required by mine. To test this Mr. Crookes mounted a radiometer in a receiver consisting of two unequal bulbs connected by a large tube. The movable portion could be transferred from one bulb to the other through the tube. In the small bulb the convection current is most impeded, and at the Fame time the heater and cooler are closest together. Mr. Crookes found that the motion of the radiometer was more rapid in the small bulb than in the large one, ia conformity with my theory, and in opposition to Prof. Reynolds's. The same is the uniform drift of a vast number of other experiments by Mr. Crookes, and of those by Mr, Moss and myself, from which it appears that whenever the heater and cooler are ma Je to approach there is an increase in the force, and that the force is not appreciably affected by variations of tl:e convection current, or by its suppression. This may also be proved, and quite conclusively, by observa- tions not requiring apparatus. Drops in the spheroidal state and the drops which are often seen floating on the surface of volatile liquids, as, for example, the drops which run about on the surface of the sea in certain states of the weather when water drips from an oar, are supported by Crookes's layers of air inter- vening between them and the liquid beneath. Similarly a red- hot copper plate will float on water, supported on a Crookes's layer, and many other instances of a like kind might be adduced. In such cases, where the film of air is thin and for the most part horizontal, it is manifest that there is no opportunity for those convection currents to arise which are required by Prof. Reynolds's hypothesis, while in all of them there are the peculiar molecular motions of my theory. The absence of convection currents which could produce an appreciable effect may also be proved in those radiometers of which the arms whisk round at a very rapid speed, and in many other cases that would take too much space to describe here. Again, a tangen'ial force which may be rendered considerable is an immediate consequence of my theory, but has no place as a consequence of Prof. Reynolds's. Now its presence has been verified by Mr. Moss and myself, and by Mr, Crookes in an exquisitely beautiful apparatus suggested for this purpose by Prof, Stokes, as well as, in a less degree, in all Mr. Crookes's apparatus with curved or crumpled discs. Hence Prof, Osborne Reynolds's hypothesis is not the ex- planation of Crookes's stress. It alleges a cause which is in certain cases a vera causa, but not the cause of what is to be explained. So far as I can form a judgment, its merit was col- lateral, and not intrinsic. It was the first attempt at a reduction of the observed phenomena to known physical laws. Though not accounting for them, it was sufficiently plausible to attract the attention of Prof, Reynolds and other physicists. It thereby had the important effect of suggesting Dr, Schuster's most valu- able experiment, which was the first that established the cardinal fact that the forces within a radiometer case are balanced. The conclusion to which we are thus led by a purely experi- mental inquiry is supported by an examination of the chief theoretie assertions of Prof. Osborne Reynolds's letter, viz., I. That an essential part of my explanation "is contrary to the law of the diffusion of heat in gases ; " and 2, " That the force arising from the communication of heat from a surface to adjacent gas of any particular kind depends only on one thing, ^q rate at which heat is communicated, and lo this it is propo:tional." Both of these statements have been set down by Pro^ Osborne Reynolds in error ; the first from not observing that the ordinary laws for the propagation of heat through a gas do not apply to compressed Crookes's layers; and the second from a misap- prehension of the actual agency at work in radiometers and other similar apparatus. I will proceed to establish these two positions. I. So long as a gas is in its ordinary state the distribution of the velocities of the molecules is the same in all directions, and when heat is imparted to the gas it does not disturb this uni- formity of structure. The heat simply increases ilie mem velocity, and the actual velocities continue lo be distributed about 8o NATURE \Nov. 29, 1877 their mean value according to the well-known exponential law, and are alike in all directions. But the gas of a compressed Crookes's layer is not in the ordinary state ; it is under con- straint, as I have elsewhere shown, oiving to the proximity of the heater and cooler between which it is confined. In consequence of this constraint there are what I have described as processions going on in the layer of gas : in other words, the velocities of (he molecules at any situation within the layer are not alike in all directions, but are greatest in the direction of the cooler, least in the direction of the heater, and of intermediate values in lateral dire :- tions. The heat in crossing the layer from the heater to the cooler maintains this polarised molecular structure, and if the How of heat is increased it does not simply increase the mean velocity of the molecules, but also augments the disparity of the velocities in different directions. Now the ordinary laws of the communication of heat to and through gas are bastd on the opposite supposition that when heat reaches any portion of the gas all the molecules of that portion are equally affected, that though their mean velocity is increased the laws of the dibtribution of the velocities about that mean, and in different directions, are not changed. Hence Prof. Osborne Reynolds has fallen into an error in applying the ordinary '* law of the diffusion of heat in gases " to the case of compressed Crookes's layers. The law employed by Prof. Reynolds does not prevail unless there is sufficient room in front of the heater for the development of a complete unrestricted Crookes's layer ; Crookes's force only presents itself when the thickness of that layer is restricted by a cooler. The transmission of heat across Crookes's layers is made the subject of investigation in a memoir which I laid before the Royal Dublin Society last May, which has recently been printed in the Transactions of that body, and of which a copy will shortly appear in the Philosophical Ma:;azine. The law proves to be enurely different from any of the laws for the propagation of heat hitherto known, and I have therefore called this mode of trans- ferring heat by a new name — the penetration of heat. Moreover, the results of theory had been verified by anticipation more than thirty years before by MM. De la Provostaye and Desains, in two elaborate experimental investigations into what we now know to have been the penetration of heat ; so that our know- ledge of its laws, which are entirely different from the laws of the diffusion of heat, quoted by Prof. Reynolds, already stands on both a deductive and experimental basis. 2. Prof. Osborne Reynolds further states that with each gas the force depends only on one variable, viz., the rate at which heat is communicated by the heater to the aijacent gas, and that it is proportional to this rate. Probably o .', ing to a mere slip on Prof. Reynolds's part, he has here omitted a second variable, viz., the temperature of the gas, which is implicitly contained in the equation of his first paper to which he refers. With this, however, I have no concern ; what I have to point out is that in making the statement, whether in an amended or in its actual form. Prof. Osborne Reynolds has overlooked the fact that the machinery of Crookes's stress consists of a cooler as well as of the heater and intermediate gas, and thit a sufficient proximity of the cooler is essential. Accordingly, the true expression for the force (of which I hope to publish an investigation made some time ago, as soon as my health will allow) is not so simple as Prof. Reynoldi supposes, but is a function of the temperatures of the heater and cooler, and of the rate at which heat reaches the . ooler by penetration, in addition to the single variable which one Prof. Osborne Reynolds admits. The vice of the mathe- matical reasoning, on which Prof. Reynolds bases his statement, is that it starts from a kinetic expresbion for the pressure of gas, which is only true when the mean of the squares of the velocities of the molecules is the same in all directions. Accordingly, his discussion does not reach the phenomenon it professes to explain; ''it is irrelevant to the case of compressed Crookes's layers, in which the gas is polarised, and where the degree of polarisation is itself a lunction of Prof. Reynolds's variable along with other thermal variables. Thus, in all parts of his inquiry. Prof. Osborne Reynolds has been led into error by having regarded the gas of compressed Crookes's layers as gas in its ordinary state ; in other words, because he has not had a glimpse of that peculiar molecular structure in the gas, which is the real source of Crookes's stress. From a review of the whole subject I think myself justified in submitting that the only discovery which brought with it any knowledge of the cause of Crookes's stress and of penetration, was the discovery that gas could assume this polarised con- dition ; and I must say that it does not appear to me that to this discovery Prof. Ooborue Reynolds has in any degree contributed. Dublin, November 15 G. Johnstone Stoney Postscript, November 23, — Pi of. Osborne Reynolds has written a further letter to Nature (vol. xvii. p. 61), in which he says : — "The fact that Mr. Stoney has in no way referred to my work, although I preceded him by some two year?, has relieved me from all obligation to discuss Mr. Stoney 's theory." I am sorry Prof. Osborne Reynolds should have thought me capable of discourtesy or inattention to the claims of a fellow-worker, and fortunately I am not conscious of being liable to the imputation. I became acquainted with Prof. Reynolds's paper in the interval between the publication of my first and second paper?, but did not refer to it in my second paper because 1 found on reading it that Prof. Reynolds's explmations of Crookes's force were all erroneous (viz., the evaporation of mercury or other vapour, and heat communicated to diffused particles of ga=;, or to gas brought by convection currents) ; because the mathematical analysis widi which he supports his [hypotheses is irrelevant to the problem with which he is dealing ; and finally, because for the purposes of my inves igation I had no occasion to point out these mistakes, inasmuch as Prof. Reynolds had not approached the subject of polarised layers of gas and their mechanical pro- perties, which was the subject matter of my papers. I ought to add a word in reference to the criticism of my memoir on penetration, which is contained in Prof. Osborne Reynolds's last letter. He seems to overlook a condition laid down in the second paragraph of my memoir, which diipo-:es of the criticism, viz. : "Let us further res^ard this gas as a perfect non-conductor of heat." Your mathematical readers will at once perceive that this condition is a legitimate simplification of the problem, because the diffusion or conduction of heat in gases is very sluggish compared with penetration, the phen jmtnjn with which I was dealing. It appears from Prof. Osborne Reynolds's last letter that my wish to make my note to Nature (vol. xvii. p. 43) a fortnight ago short, led me to make it obscure. I will ttierefore, with your permission, try to state the matter more clearly. As I understand the scientific question in discussion before us, it is this : — Assuming (l) that, when heat is communicated from a solid surface to a gas in contact with it, a force arises (equiva- lent to a pressure against the surface) which is proportional to the rate of communication of heat, and (2) that the conducting power of a gas for heat is independent of its density, Prof. Reynolds concludes thit the driving-force on the vanes of a radiometer does not increase with the rarefaction of the air, but that rarefaction favours the motion only in so far as it lesssni the opposing force due to convection- currents. I, on the other hand, while admitting Prof. Reynolds's premisses, do not admk his conclusion. On the contrary, I believe that, in the radio- meter, rarefaction must increase the rate of communication of heat, and hence also the force. To see how this may be, 1 t A B represent the thickness of a stratum of gas contained between two parallel solid surfaces, whose temperatures, measured from any zero, are represented respectively by A c and B D. Then, I imagine, the flow of heat through the gas will take place as though there were, in contact with each solid surface, a layer of gas whose temperature is throughout the same as that of ths contiguous solid, and whose thickne;s is equal (or at leist pro- portional) to the mean length of path of the molecules. The virtual thickness of the stratum of gas, whose conductivity comes into account in determining the rate of transmission of heat, is then the actual thickness diminished by the aggregate thicknesses of these two layeis. For example, if Aa and B^ represent the thicknesses of the hot and cold layers respectively, the virtual A CO ccl I HB thickness of the stratum across whic'i conduction takes place is ad, and the distribution of temperature from side to side of the whole quantity of gas is given by the ordinate^ of the ISIov. 29, 1877] NATURE 81 broken line ccdvt. If now! the gas is rareSed, the mean length of path of the molecules, and consequently the thickness of each of the layers of uniform temperature, is increased, and the thickness of the stratum acro-s which true conduction takes place is diminished. If, for example, the thicknesses of the layers become A a' and Tib', the thickness of the con- ducting stratum is reduced to a'b\ and the distribution of tem- perature is represented by the ordinates of the broken linec/^/o. The rate of flow of heat in the two cases will be proportional conjointly to the inclination of the line cd or dd to ar, and to the conductivity of the gas ; but as the latter factor does not vary with density, the result is proportional to the former only. It is evident that if this view of the matter is approximately correct rarefaction must increase the rate of transmission of heat across a stratum of gas whenever the increased length of path of the molecule?, resulting from rarefaction, bears an appreciable proportion to the thickness of the stratum, but that it will have no sensible effect of the kind when the stratum of gas is very thick or the rarefaction itself very small. I I ought to acknowledge that precisely' this mode of representing the effect of rarefaction occurred to me only as I was thinking how I could comply with Prof. Osborne Reynolds's wish that I should be "more explicit." When I wrote my last note I had in mind a somewhat different mode of action whereby it seemed that an equivalent result to that here pointed out would be brought about. The further consideration which Prof. Rey- nulds's letter in this week's Nature has caused me to give to the subject has, however, led me to think that the view given above is not only clearer, but also a nearer approach to a correct repre- sentation of the facts than the one I had previously adopted. But apart from the accuracy of any particular explanation of how such a result can occur, the experimental evidence seems to me to prove conclusively that the force in the radiometer does in- crease (up to a certain point) with rarefaction. The action of convection currents depends to so great an extent on such con- ditions as the size and shape of the envelope and the position of the fly, and they must be so much disturbed as soon as the vanes begin to move, that if they played the essential part which I understood Prof. Reynolds to attribute to them, I cannot think that the effect of rarefaction would present anything like the degree of regularity that has been actually observed. November 24 G. Carey Foster Mr. Crookes and Eva Fay The precise nature and grounds of the attestation given by Mr.' Crookes to Eva Fay's "mediumship" appear in an article entitled "Science and Spiritualism" in the Daily Tele- graph for March 13, 1875, embodying a communication made by Mr. Crookes himself to the Spiritualist of the preceding day. The readers of Nature will be able tojudge for themselves by the following extracts from this article, whether Eva Fay was not fully justified in announcing her " mediumship " to the American public as having received Mr. Crookes's "endorsement." "In the Spiritualist of yesterday, Mr. William Crookes, r.R.S., prints an account of a seance at his house in which Mrs. Fay exhibited some remarkable phenomena while under severe scientific conditions. The sitting took place on Friday evening, February 19, in the presence of several well-known men of science ; and, on Mr. Crookes's suggestion, the mtdium was so placed as to form part of an electrical current connected with a galvanometer, indicating on a graduated circle the exact deflection produced by the current. In each hand Mrs. Fay held the ter- minal of a wire, and the fact that she kept continuous hold of the terminals was guaranteed by the amount of deflection of the galvanometer needle, and by the flashes of light which accompany each change of position or break of contact. This method was agreed to by the savants present, as affording absolute certainty that the medium could not remove her hand or body from the wircB, whether in a trance or otherwise, without the fact being made known by the galvanometer. The sitting was held in a well-lighted drawing-room, the medium thus * tied down by electricity' being screened by a curtain. What followed is thus described by Mr. Crookes : — " We commenced the tests at 8. 55 P.M. ; the deflection by the galvanometer was 211 deg., and the resistance of Mrs. Fay's body 6,600 British Association units. At 8.56 the deflection was 214 deg., and at this moment a handbell began to ring in the library. At 8.57 the deflection was 215 deg. A hand came out of the cabinet on the side of the door farthest from Mrs. Fay."' A number of other occurrences of the like kind are then recorded ; the hand reappearing from time to time, and presenting diflferent members of the pirty with books and other articles severally appropriate to each, of which Mr. Crookes considered it impossible that Mrs. Fay could herself have gained possession. He adds : — " Before Mrs. Fay came to the house that evening, she only kne.v the names of two of the guests who would be present ; but during the evening the intelligence at work dis- played an unusual amount of knowledge about the sitters and the labours of their Jives." The entire extract (which I should have reproduced in full it the space of Nature had permitted) would show that — i. It is true that Mr. Crookes gave his public attestation to the genuine- ness of the so-called spiritualistic manifestations which occurred in his house through the " mediumship " of Eva Fay. 2. It is true that Eva Fay went back to the United States armed with Mr. Crookes's public attestation oi the genuineness of the performances which took place at his house, 3. It is true that Mr. Crookes wrote a letter to a gentleman in the United States, giving a similar attestation, which letter was published in facsimile in an American newspaper. — The only thing that was «^jf true in my statement, was that (through having mislaid the slip containing it) I spoke of this letter as having been addressed to Eva Fay herself, and having been written before her departure. 4. It is true that Eva Fay's public performances in London were imitated at the time by Messrs. Maskelyne and Cooke ; and further, that her business agent spontaneously offered Mr. Maskelyne to expose (for a sum of money) the tricks by which she cheated "the F.R.S. people." — If Nature thinks it worth while to admit into its columns the full particulars of that offer, Mr. Maskelyne is quite ready to furnish them. His general assertion of the fact has been long before the public ("Modern Spiritualism," p. 122), and has remained unchallenged, so far as I am aware, until now. 5. It is true that the whole modus operandi of Eva Fay's public "manifestations" in the United States has been publicly exposed in New York and Boston by Mr. Washington Irving Bishop, as stated in Fraser's Magazine for the present month. It was riot only in entire ignorance of these proceedings, but under the influence of a report in circulation among the Fellows of the Royal Society — that " Mr. Crookes had given up Spiri- tualism," that I expressed to Mr. Crookes, on the occasion of his receiving the Royal Medal, my desire to "bury the hatchet." But I most assuredly did not consider myself thereby pledged to keep silence in regard to any further proceedings of the like kind ; and only learned at the beginning of the present year that Eva Fay had been trading on the " endorsement " gi 'en her by " Mr. Crookes and other Fellows of the Royal Socie.y,"' which she natu- rally " improved " into that of " the Royal Society of England." November 19 Willi .01 B. Carpenter Potential Energy Will you permit me to express a certain amount of scep- ticism as to the reality of Mr, O'Toole's troubles on this subject ? That some statements made in the text-books quoted are not clear — that by an ingenious collocation of isolated passages from different authors some absurd conclusions may be drawn — we admit, but it may be doubted whether a Publius with the keen critical power of Mr. O'Toole would not be able to eliminate these errors or ambiguities by a reference to the context. In support of this position let us take the points raised by Mr. O'Toole in the order adopted by him. A. — Potential E,, as meaning Energy in posse. The ' ' doctors " quoted, with one exception, represent poten- tial E. — not as energy itt posse, but as kinetic energy in posse — a very different thing. Just as gold coin — though certainly not money in posse — may correctly be called silver coin (another form of money) in posse. But it is said this name — and certain phrase? employed by the doctors — imply that potential E. is "energy of about-to-su- pervene motion, or that it does not perform work except through the resulting E. of motion," Mr. O'Toole is so dis- tressed because poor Publius is susceptible to this impression, that I feel some hesitation in asking what is wrong in it? How can work be done without motion? How can the poten- tial E. of a system change without a change in the con- figuration— i.e., motion of the system? Where is the mistake in the conception of potential E. continuously changing into kinetic energy, and this into work, as suggested by poor " P, M.," who; was so summarily treated by this terrible O'Toole that I quake in my shoes as I think of my fate. 82 NATURE [Nov. 29, 1877 The exception mentioned above is an extract from Clerk Moxwell, which is certainly erroneous, and from which Mr. O'Toole gets a good deal of fun. We will not suggest that the addition of a single word would make the passage correct, for we should be told^ that text-books ought to be perfect. _ But it is only just to mention that the error occurs in an explanation of the name ; in the definition of the thing the error does not occur ; nay, it is expressly contradicted. After this is it not unkind to condemn tho?e doctors who drop the name " potential E." and replace it with such phrases as •' E. of repose," &c., implying that the energy in question is not due to motion? By-the-by where is the bull in "passive energy"? and what is the "action" that may be confounded with kinetic energy ? B.- -Potential E, as meaning " Energy related to Potential Funetions." The word Potential may be used in a second sense. This of itself is a trouble to INIr. O'Toole ; but— remembering that your readers may not sympathise with his undisguised antipathy to verbal skylarking — he hastens to add that the two meanings are not only heterogeneous but incompatible. " Surely there is no occasion to stop to prove this." Please do, Mr. O'Toole; we should like to hear you prove something. It may be noted that in this opinion and in paragraph 9 he appears to differ from Thomson and Tait. (See their definition of Potential, Nat. Phil., vol. i., § 485). C— Potential E. as meaning " Energy of Potency " It appears from a foot-note that " potency " may mean a force. If so, it is strange that the O'Toole— who, throwing off his thin disguise, at the end of Lis letter undertakes the "duty" of a doctor, and tells us that potential E. should be the " energy of a force " — it is strange that Dr, O'Toole should object to the name on this ground. But the remarks under this head are chiefly interesting, as indicating the modus operandi of our pseudo-Publius. He does not trouble to examine the definitions of "potential energv." He only looks for explanations of the word " potential." Find- ing scant material in the doctor's utterances, he resorts to his dictionary, hunts up the different meanings of " potential," adds to these their antitheses, and rends his phantoms to pieces. It is scarcely a parody upon his letter to say — we won't trouble about what a civil engineer is, but let us examine the meaning of civil. Now civil has" meanings : ( A.) polite, (B.), &c, Therefere "civil E." means "polite E.," and "civil E." used as a distinguishing title cannot mean anything else than this, that the other E. is unpolite E. As to the whereabouts of Potential Energy. " We shall now pass from the perplexities 'connected with this imlucky name, 'potential E.,' to consider the behaviour of our teachers towards the thing itself." At last Mr. O'Toole will deign to discuss the definitions given by the doctors. Nay, he wanders away into an examination of such rash— but perhaps not inexcusable— phrases as "the potential E. of a raised weight," &c. The proper remedy for the troubles arising on this pomt is "to use words discreetly and comistently." But this is not sufficiently heroic. A local habitation must be found for this "potential E.," although it would seem as vain to inquire into the whereabouts of potential E. as into the whereabouts of Mr. O'Toole's scientific erudition. It is proposed to lodge this E. in the forces, and perhaps it won't do much harm, as we don't know where the forces are. It is proposed, moreover, to sub- stitute "energy of tension " for " potential E," This done, the doctor's millennium will have come. Never mind about altering your conception of this kind of energy ; call it by another name ; give it a weis7iichtwo lodging. There will be no more " confusion about fundamental principles ; " there will be no more slips of the pen or tongue ; theie will be no more puzzled Publii ; and last, but not least, there will be no more O'Tooles to bother the doctors. Well may " verbal skylarking " be despised. What is it beside such gigantic fun as this? ' And yet I am sceptical. We started by hearing that it was "principally — though not entirely — the doctors who were to blame for this confusion about fundamental principles." Is this proved? Is not another cause indicated in the letter of of "E. G." (vol. xvii. p. 9)? And shall the doctors expect to be rightly understood when Dr. O'Toole's amanuensis admits (vol. xvi. p. 520) that Dr. O'Toole himself has been misappre- hended upon almost every point by one reader at Iea-.t? Cirenctiter, November 13 H". W. Lloyd Tan.ner Smell and Hearing in Moths In Nature fvol. xvii. p. 72) your correspondent " E. H. K," observes : " 'J. C seems to draw inferences that moths have not the power of smell, but have that of hearing. I feel quite certain they possess the former, but am in doubt about the latter " With reference to the sound of the glass, is it not the quick motion of the hand which disturbs the moth ? " May I draw the attention of both your correspondents to sonae experiments of mine on this subject which were published in Nature about a year ago ? These experiments, I remember, were quite sufficient to prove to me that moths have the power of hearing shrill notes ; and, until I read the query of " E. H. K." above quoted, I thought that my account of these experiments must have been equally conclusive to any one who read them. On now referring to that account, however, I find that I there omitted to state one of the experiments which was resorted to for the purpose of avoiding the possible objection which " E. II. K." now advances. This experiment was a very simple one, consisting merely in making a sudden shrill whistle with my mouth by drawing the breath inwards, so as not to disturb the air in the neighbourhood of the insect. The latter, however, always responded to this as to other sounds in the way described, although throughout the experiment I took care not to move any part of iny body. George J. Romanes It was because of my knowledge of facts like those named by " E. H. K." that I was surprised at the apparent inability of moths to smell ammonia. Being no physiologist, I ventured to draw no inferences ; but it occurred to mc to wonder whether the sense of smell differs in kind with d>fferent organisations ; whether, for instance, some substances strongly odorous to us may be quite inodorous to insects, and vice versa. As to the experiment on hearing, I do not think it was the movement of the hand which startled the moths. It may con- conceivably have been the vibration of their wings set up by the sound ; but the experiment can easily be repeated with variations by any one interested in the subject. J. C. Loughton Meteorological Phenomenon This morning at about a quarter before ten the sky here pre- sented a most unusual appearance. The air was calm and the sun shining, but not brightly, through a slight veil of cirro- stratus. The sky was mostly covered with fibrous clouds of cirrus or cirro-stratus (I am not quite sure which I ought to call it), the fibres being quite parallel to each other, but in two different strata ; those of one stratum were approximately from north-east to south-west, those of the other from north-west to south-east—so that they seemed to cross each other like the threads of a woven fabric. I think the fibres from north-east to south-west were the highest, but am not quite sure, though it seemed the same to another who was looking on with me. Joseph John Murphy Old Forge, Dunmurry, Co. Antrim, November 25 OUR ASTRONOMICAL COLUMN Stellar Systems. — M. Flammarion, in various notes communicated recently to the Paris Academy of Sciences, has been drawing attention to stars which appear to be affected with a common proper motion, or a motion similar in amount and in its direction. Several of his cases, however, are by no means to be styled " Nouveaux systemes Stellaires." Thus the large and uniform proper motions of the southern stars ^' and f^ Reticuli, to which he refers in the Cotnptes Rendns of November 5, were the subject of remark in ;^Nature, vol. xi. p. 328. That there was a probability of a common proper motion in these stars would be evident to any one who inspected the columns in the British Association Catalogue, published in 1845, but as Taylor had not observed them, and the comparison was consequently dependent upon Lacaille and Brisbane only, there was a possibility of mistake. The first confirmation of the large proper motion of the B.A.C. in f ■ was afforded in Jacob's "mean places of 1440 stars"— from the Madras observations 1849-53, and Nov. 29, 1877] NATURE 83 the earliest proof of a common translation in space was given by the same observer from the Madras observations 1853-58, which formed a part of vol. xxviii. of the Memoirs of the Royal Astronomical Society. Not having seen any distinct reference to the very large and uniform motions of these stars in astronomical treatises, we adverted to them in Nature as above. Again, the common proper motions of Regulus and Lalande 19749, mentioned by M. Flammarion in the same communication have been long remarked. The same may be said in the case of 9 and 10 Ursae Majoris, one of the systems to which he refers in a paper presented to the Academy on November 12. Any one who has carefully utilised the very valuable fourteenth volume of the Dorpat observations must have been familiar with this case, and, we may add many similar ones, though the proper motions involved may be to smaller amount. This volume contains Madler's laborious work upon 3222 of Bradley's stars, of which he gives positions reduced to 1850, and where all the catalogues available at the time and con- sidered deserving of confidence were brought to bear. Not the least important feature in this work is the addition of two columns, not usually found in catalogues, contain- ing the amount of secular proper motion in arc of great circle {r) and the angular direction of this motion (0) counted from north round by east to 360°. On p. 155 we have — For 9 i Ursae Majoris ... r= 52"-5 ... = 238°'9 „ 10 „ .... r- S2"-6 ... (/> = 238'-5 But, as we have stated, other similar cases are readily detected by an inspection of these columns. For in- stance : in y and 58 Tauri, distant 35', where r= 13", 0 = 97° ; in 66 and 68 Draconis, distant 43', r = I3"*5, c/) about 69° and for wider stars, in 26 and 34 Pegasi, dis- tant 4° 25', where r = 30''', 0 = 84° ; in rj and 10 Arietis, distant 5° 11', r= is"'5, 0 = 86°, with other neighbouring stars, moving in nearly the same direction, and again in fi and 54 Aquilas, distant 5" 13', r = 27", (j) = 121°. The hst might be largely increased. It is nevertheless to be expected that the researches which M. Flammarion is so industriously following up with respect to stellar systems may lead to a considerable addition to our knowledge of them, in cases which are not thus easily discovered from existing catalogues, par- ticularly by determining the proper motions of stars, not yet submitted to such investigation. The Minor Planets.— A letter from Prof. Watson, of Ann Arbor, U.S., to M. Yvon Villarceau, dated November 5, deranges the ordinal numbers of the small planets given in this column last week, from No. 175 onwards. It appears that on October i he discovered a planet lom., which he duly notified by telegraph to the Smithsonian Institution, but by some unexplained cir- cumstance the information was not transmitted by cable to the Observatory of Paris, as usual with such dis- coveries. Supposing this object to be really a fiera planet, it will be No. 175, and the subsequent discoveries mentioned last week will be on the same supposition, advanced a unit. Elements of No. 172 appear in Astron. Nach., No. 2,176, and of No. 176 in the Paris Bulletin International of November 25. The Cordoba Observatory.— Within the last few days, Mr. John M. Thome, the zealous co-operator with Dr. B. A. Gould in the important astronomical work carried on for several years past at the Observatory of the Argentine Republic, has visited this country on his return to Cordoba from the United States. We have seen in his hands proofs of the charts of the Argentine " Urano- metria," which are on a much larger scale than those of Argelander, Heis, and Behrmann. They have been engraved in New York. This work is expected to be soon published ; also large lunar photographs taken at Cordoba. All the stars in the " Uranometria" have been meridionally observed. CARL VON LITTROiV r^ARL LUDWIG VON LITTROW, whose death has ^^ been announced during the past week, was born at Kasanonjuly 18, 181 1, His father, Joseph Johann von Lit- troA', the eminent astronomer, afterwards Director of the Imperial Observatory at Vienna, was at that time Professor of Astronomy in the Universityof Kasan.where he founded an observatory. The son was educated under the father's direction, and in 1831 was appointed assistant at the Observatory at Vienna, of which institution the elder Littrow had taken the superintendence in 1819, removing thence from Ofen. In 1835 he first appeared as an astronomical writer, having in that year published an account of Hell's Journey to Wardoe and of his Obser- vations of the Transit of Venus in 1769 at that place, from the original day-books ; also a History of the Dis- covery of General Gravitation, by Newton, and Treatises upon Comets, more especially on Halky's, which was then appearing. In 1839 he published at Stutgard a Celestial Atlas, and a work which in the Catalogue of the Pulkova Library is called a Translation of Airy's " Popu- lare physische Astronomic," by which is most probably intended the well-known Treatise on Gravitation pub- lished by the Astronomer-Royal in 1834, though elsewhere Littrow's work is stated to refer to the history of Astro- nomy during the early part of the nineteenth century, presented to the British Association in 1832. In 1842 Carl von Littrow succeeded his father as "Director of the Observatory of Vienna, and the establish- ment has continued in vigorous activity under his charge. He has principally devoted the energies of the Obser- vatory to equatorial astronomy, following up with dili- gence the observations of comets and planets, and with the aid of able assistants determining their orbits. Some of the most complete com^tary discussions have emanated from the Observatory of Vienna while under his charge. The Annalen der Sternwarte in Wien, have been continued, and valuable, astronomical work is contained in them, as for instance in the first volume of the third series, which appeared in 185 1, where we have the positions of the stars in Argelander's Northern Zones reduced, by Oeltzen to 1842, the epoch for which elements of reduction were given in the Bonn volume. Littrow was a frequent contributor to the publications of the Vienna Academy. In one of his memoirs — " Bahnahen zwischen den periodischen gestirnen des Sonnensystems," printed in the Sitzungsberichte of the Academy for January, 1854, he applied an original process of investigation of the points of nearest approach amongst the orbits of the small planets discovered up to that time, and the orbits of the periodical comets — a troublesome work in which mechanical aid was introduced ; the result was the dis- covery of many close approximations of planets with planets, planets with comets, and of comets with comets ; amongst the latter near approaches of Biela's comet to the orbit of Halley's in 35° and 198" heliocentric longitude. When interest was excited relative to the expected return of the comet of 1556, which at that period was supposed to have been previously observed in 1264, Littrow was the means of bringing to light an unknown treatise by Heller, which, with the chart of Fabricius, has allowed of a much improved determination of the orbit, and similarly he made known interesting particulars with reference to the remarkable observation by Steinheibel and Stark of a rapidly-moving black spot upon the sun's disc on February 12, 1820. Littrow was a constant contributor to the columns of the Astronofnische Nachrichten. The names of Hornstein, Oeltzen, Weiss, Schulhof^ and others are well known in connection with the work of the Vienna Observatory during Littrow's direction. His death occurred on the i6th inst. Von Littrow's wife, Auguste Littrow-Bischoff, is one of the best known Austrian authoresses of the present time. The genial qualities of the astronomer and his wife made H NATURE [Nov. 29, 1877 them the centre of a large and admiring circle, and their residence was one of the most favourite gathering-places of the literary and scientific celebrities of Vienna. BACTERIA ^ IN a short paper communicated to the Royal Society at the close of last session, Prof. Tyndall did me the honour to criticise certain words reported to have been used by me at a meeting of the Association of Medical Officers of Health in January last. Although I am much indebted to him for the opportunity he has thus afforded me of discussing an important subject before this Society, I cannot refrain from expressing my regret that he should have thought it desirable to quote at length, and thus to place on permanent record in the Society's Proceedings, the expressions used on the occasion above mentioned. I regret this because these expressions occur in an abbre- viated and incomplete abstract of a hastily prepared discourse not intended for publication. As, however, I am well aware that Prof. Tyndall's purpose in his communication was not to criticise the language, but the erroneous views which the language appeared to him to contain, I shall make no further reference to the quotation ; but shall regard it as the purpose of the present paper, first to reply to the reason- ing embodied in his last communication, and secondly to corroborate certain statements previously made by me, to which he has taken exception in the more extended memoir published in the i66tlx volume of the Philosophical Transactions. It will be my first object to enable the Fellows of the Royal Society to judge how far the views I entertain differ from those which have been enunciated here and elsewhere by Prof. Tyndall. Biologists are much indebted to him for the new and accurately observed facts with which he has enlarged the basis of our knowledge, as well as for the admirable methods of research with which he has made us acquainted. As regards the general bearing of these facts on the doctrine of Abiogenesis, I imagine that we are entirely agreed. So far as I can make out, the difference between us relates chiefly to two subjects, namely, the sense in which I have employed the words " germ " and " structure," and the extent of the knowledge at present possessed by physiologists as to the structure and attributes of the germinal particles of Bacteria. Although Dr. Tyndall, in the title of his paper, refers to my "views of ferment," yet as he makes no further allusion to them, I will content myself with stating that in the passage quoted, the first sentence (from the words " In defining" to the word "living") has nothing to do with the following sentences, having been placed in the position which it occupies in the quotation by the abstractor. The paragraph ought to begin with the words " Ten years ago." Of the meaning which attached itself to the word " germ " in the days of Panspermism a correct idea may be formed from the following passage from M. Pasteur's well-known memoir " Sur les Corps organises qui existent dans 1' Atmosphere." " There exist," says he, " in the air a variable number of corpuscles, of which the form and structure indicate that they are organised. Their dimen- sions increase from extremely small diameters to one- hundredth of a millim., i"5 hundredth of a millim., or even more. Some are spherical, others ovoid. They have more or less marked contours. Many are translucent, but others are opaque, with granulations in'^their interior. .... I do not think it possible to affirm of one of these corpuscles that it is a spore, still less that it is the spore of a particular species of microphyte, or of another, that it is an egg or the egg of a particular microzoon. I confine myself to the declaration that the corpuscles are • " Remarks on the Attiibutes of the Germinal Particles oi Bacteria, in reply to Prof. Tyndall," by J. Burdon-Sanderson, M.D. , LL.P., F.R.S. Paper read at the Royal Society, November 22, evidently organised ; that thejr reaemble in every respect the germs of the lower organisms, and differ from each other so much in volume and structure that they unques- tionably belong to very numerous species." Such are the "germs" of M. Pasteur, and such is the conception of a germ which was entertained by informed persons up to 1870, and is very generally entertained up to the present moment.' It is obvious that these " corpuscules organises " were, if they had any relation to Bacteria, not bacterium germs in Dr. Tyndall's sense, but "finished organisms," and yet it was of these that M. Pasteur said that it was "mathematically proved" that they were the originators of the organisms v^^hich are developed in albuminous liquids containing sugar, when exposed to the atmosphere. With reference to the word " structure " I would point out that in the passage quoted from my lecture it is dis- tinctly stated that the bacterial germ is endowed with structure in the molecular sense, but not in the anatomical sense. The meaning of the expression " anatomical structure" was, naturally, not defined, considering that the persons whom I was addressing might be supposed to be familiar with it. As, however, my failing to do so has apparently led to some uncertainty as to my meaning, I must, to avoid future misunderstandings, define more com- pletely the difference between the two senses in which the word was used by me. The anatomical sense of the word structure may be illustrated by referring to its synonyms, to the English words texture and tissue, to the Greek word la-rlov, and to the German word Gewcbe, from vv^hich two last the words in common use to designate the science of structure, viz., histology and Geivebelehre are made up. What I have asserted of the germinal particles of Bacteria is, that no evidence exists of their being endowed with that par- ticular texture which forms the subject of the science of histology. In biological language there is a close relation between the words structure and organization, the one being an anatomical, the other a physiological term ; either of these words signifies that an object to which it is applied consists of parts or structural elements, each of which is, or may be, an object of obser- vation. As the observation is unaided or aided, the structure is said to be macroscopical for microscopical. The biologist cannot recognise ultra-microscopical structure or organisation except as matter of inference from observation, i.e., from observing either that other organisms, which there is reason to regard as similar to the object in respect of which structure is inferred, actually possess visible structure, or that the object can be seen to possess structure at a later period of its existence. As instances in which the existence of structure is inferred the following may be mentioned : — The protoplasm of a Rhizopod is admitted to have structure because, although none can be seen in the protoplasm itself, the compli- cated form of the calcareous shell which the proto- plasm makes or models can be seen. By analogy therefore other organisms which are allied to the Rhizo- pod are inferred to have structure, and from these, or from similar cases, the inference is extended to all kinds of cells, with respect to which it is taught by physiologists that although, in certain cases, no parts can be distin- guished, the living material of which they consist is nevertheless endowed with structure or organisation. Similarly, we assume, that a Bacterium possesses a more complicated structure than we can actually observe, because in other organisms which are allied with it by form and life history, such complications can be seen. Again, in all embryonal organs we admit the existence of structure before it can be seen, because in the course of 1 Before I became aware that the contaminating particles of water are ultra-microscopical I myself was engaged earnestly in huntmg for germs both in water and air. The search ha-; been continued by others up to a much later period. Those who desire information on the organised particles of the atmosphere will find the subject exhau-tively treated by Dr. Douglas Cunningham in a report entitled "Microscopical Examinations of Air," lately issued by H.M. Indian Government. I^ov. 29, 1877] NATURE 85 development we observe its gradual emergence. So far, inference of the existence of structure from historical evidence is justifiable ; but if we were to carry this inference back to the ovum itself, and say that the cha- racteristic structures of nerve, of muscle, or of gland, exist in the ovum at the moment after impregnation, every physiologist would feel the assertion to be absurd. In the familiar comparison of the origin of the elephant with that of the mouse, in which the perfect anatomical similarity of the ova in the two species is contrasted with the enormous difference of the result, we should be jus:i- fied in saying that the difference of development is the expression of structural difference between the primordium of the one and the primordium of the other ; but inasmuch as it is not possible to indicate any anatomical distinction, it is understood that structural difference of another kind is meant, namely, difference of molecular constitution. In other words, we assume that the potential difference between the one and the other is dependent on an actual difference of molecular structure. Whether this is accom- panied with an ana'omical difference, such as we might expect to be able to see if we had more perfect instru- ments, we do not know. From the moment that it is understood that the word structure means anatomical structure, the argument used by Dr. Tyndall loses its relevance. After referring to the " germ limit," he says, " some of those particles " (by which, I presume, is meant atmospheric particles) "de- velop into globular Bacteria, some into rod-shaped Bacteria, some into long flexile filaments, some into impetuously moving organisms, and some into organisms without motion. One particle will emerge as a Bacillus anthracis, which produces deadly splenic fever ; another will develop into a Bacteriutn, the spores of which are not to be microscopically distinguished from th )se of the former organism ; and yet these undistinguishable spores are absolutely powerless to produce the disorder which Bacillus anthracis never fails to produce. It is not to be imagined that particles which, on development, emerge in organisms so different from each other, possess no struc- tural differences. But if they possess structural differences they must possess the thing differentiated, viz., structure itself." Throughout this passage it is evident that it is not anatomical but molecular structure that is referred to. In the other passages relating to the subject, I venture to think that Dr. Tyndall has overlooked the distinction made by me between anatomical organisation and mole- cular structure. When, for example, he speaks of " germ structure " in the passage quoted from his Liverpool Address, he evidently refers to molecular structure exclu- sively, for he gives ice as his first example, and argues that as ice possesses structure so do atmospheric germs — a proposition which I should not have thought of ques- tioning. The experimental evidence which we have before us goes to prove that in all the known cases in which Bac- teria appear to originate de iwvo — that is to say in liquids which are at the moment of their origin absolutely free from living Bacteria — they really originate from " par- ticles great or small," which particles are therefore germs in the sense in which that word is used by Prof. Tyndall. To illustrate the views I myself entertain, and always have entertained on this question, I need only refer to my paper on the origin of Bacteria, published in 1871. The experiments mide by me at that time brought to light the then new fact, now become old by familiarity, that all exposed aqueous liquids, even when absolutely free from visible particles, and all moist surfaces, are contaminated and exhibit a power of communicating their contami- nation to other liquids. As regards water and aqueous liquids in general, I insisted on the " particulate" nature of the contaminating agent, and coined for the purpose the adjective I have just employed (which has been since adopted by other writers), at the same time pointing out that the particles in question were ultra-microscopical, and consequently that their existence was matter of in- ference as distinguished from direct observation. Dr. Tyndall has demonstrated by the experiments to which I have already alluded, that the ordinary air also contains germinal particles of ultra-microscopical minuteness. Of the completeness at>d conclusiveness of those experiments I have only to express the admiration which I, in common with all others whose studies have brought them into relation with the subject, entertain. That such particles exist there can be no question ; but of their size, struc- tural attributes, or mode of development, we know nothing. Prof. Tyndall, I am sure by inadvertence, has accused me of assuming that there is some relation between the limit of microscopical visibility and what he calls the molecular limit, by which I presume to be meant the size of the largest molecule. Nothing that I have said or written could justify such a supposition. My contention is not that the particles in question are of any size which can be specified, but, on the contrary, that we are not in a position to form any conclusion as to their size, except- ing that they are so small as to be beyond the reach of observation. Dr. Tyndall has taught us, first, that the optical effects observed when a beam of light passes through a particulate atmosphere are such as could only be produced by light-scattering particles of extreme minuteness ; and, secondly, that by subsidence these par- ticles disappear, and that the contaminating property of the atmosphere disappears with them. He has thus approximately determined for us the upper limit of mag- nitude, but leaves us uncertain as to the lower ; for we have no evidence that the particles which render the atmosphere opalescent to the beam of the electric lamp may not be many times larger than those which render it germinative. Consequently, the fact that the air may be rendered sterile by subsidence, while affording the most conclusive proof that germinal matter is not gaseous, leaves us without information as to the size of the par- ticles of which it consists. Of each germinal particle, whether inhabiting an aqueous liquid or suspended in the atmosphere, it can be asserted that under conditions which occur so fre- quently that they may be spoken of as general (via., moisture, a suitable temperature, and the presence of dead proteid matter, otherwise called organic impurity), it produces an organism. If, for the sake of clearness, we call the particle a and the organism to which it gives rise A, then what is known about the matter amounts to no more than this, that the existence of A was preceded by the existence of a. With respect to A we know, by direct observation, that it is an organic structure ; but inasmuch as we know absolutely nothing as to the size and form of a, we cannot even state that it is transformed into A, much less can we say anything as to the process of transformation. Considering that it is admitted on all hands that there exist in ordinary air particles which are potentially germs, it might at first sight appear needless to inquire whether or not this fact is to be regarded as carrying with it the admission that they must necessarily possess the other attributes of organised structure. Very little considera- tion, however, is requisite in order to become convinced that this question stands in relation with another of fundamental importance in biology— that, namely, of the molecular structure of living material.^ It is not neces- sary for my present purpose to do more than to indicate the nature of this relation. As regards every form of living matter, it may be stated that, quite irrespectively of its morphological characteristics, which, as we have seen, ' The reader who is interested in this subject will find it discussed with ereat ingenuity by Prof, f Huger, in his paper " Ueber die phvsio'.ogische Verbrennung in den lebendigen Organismen," Pfiilgers Atchiv, vol. x. p. 300. F2 86 NATURE [Nov. 29, 1877 must be learnt by the application of the various methods of visual observation at our disposal, it possesses mole- cular structure peculiar to itself. We are certain of this, because the chemical processes of which life is made up are peculiar, that is, such as occur only in connection with living material. Even the simplest instance that we can mention, that of the elevation of dead albumin into living (a process which in the case now before us must represent the very earliest step in the climax of develop- ment) is at the present moment beyond the reach of investigation ; for as yet we are only beginning to know something about the constitution of non-living proteids. But this want of knowledge of the nature of the ditference between living and non-living material in no wise impairs the conviction which exists in our minds that the difference is one of molecular structure. The sum of the preceding paragraphs may be stated in few words. Wherever those chemical processes go on, which we collectively designate as life, we are in the habit of assuming the existence of anatomical structure. The two things, however, although concomitant, are not the same ; for while anatomical structure cannot come into existence without the simultaneous or antecedent existence of the kind of molecular structure which is peculiar to living material, the proof is at present wanting that the vital molecular structure may not precede the anatomical. At the same time it must be carefully borne in mind that there is no evidence of the contrary. It is sufficient for my purpose to have shown that the existence of organised particles endowed with anatomical structure in the "atmospheric dust" has not been proved. I do not dispute its probability. Before leaving this subject I may be permitted to add a word as to the bearing of this discussion on a question which, to myself, is of special interest — that of contagium vivum. According to the view which these words are understood to express, the morbific material by which a contagious disease is communicated from a diseased to a healthy person consists of minute organisms, called " disease-germs." In order that any particle may be rightly termed a disease- germ 'two things must be proved concerning it, viz., first, that it is a living organism ; secondly, that if it finds its way into the body of a healthy human being, or of an animal it will produce the disease of which it is the germ. Now there is only one disease affecting the higher animals in respect of which anything of this kind has been proved, and that is splenic fever of cattle. In other words, there is but one case in which the existence of a disease-germ has been established. Comparing such a germ with the germinal particles we have been discussing, we see that there is but little analogy between them, for, first, the latter are not known to be organised ; secondly, they have no power of pro- ducing disease ; for it has been found by experiment that ordinary Bacteria may be introduced into the circulating blood of healthy animals in considerable quantities with- out producing any disturbance of health. So long as we ourselves are healthy, we have no reason to apprehend any danger from the morbific action of atmospheric dust, except in so far as it can be shown to have derived infectiveness from some particular source of miasma or contagium. I now proceed to the second part of my communica- tion, which relates to Prof. Tyndall's serious, but most courteously-expressed, criticisms of my experiments on spontaneous generation/ ' The expressions referred to are the following: — " I have worked with infusions of precisely the same specific giavity as tho^e employed by Dr. Bastian. This I was especially lareful to do in relaiion to the experiments .described and vouchi d for, 1 tear incautiously, by Dr. Burdon-Sanderson, in vol. vii. p. 180 of Natire. It will there be seen that though failure attended some of his efforts, Dr. Bastian did satisty Dr. Sander.-on that in boiled and hermetically tea'ed flasks Bacteria sometimes appear in swarms. Wuh purely liquid infusions I have vainly sought to reproduce the evidence which convinced Dr Sar.dtrson I am therefore compelled to con- clude that Dr. Sandtrson has lent the authority of his name to results whose antecedents he bad not suflEciently examintd." Phil. Trans., vol, clxvi. The fact that Dr. Tyndall blames me for incautiously vouching for is, "that in boiled and hermetically-sealed flasks Bacteria sometimes appear in swarms." From multiplied experiments he concludes that this is not true, and infers that I who vouched for it was incautious. The paper referred to was one in which I, as a bystander, gave an account of certain experiments which Dr. Bastian performed in my presence. So far as relates to the fact above quoted, these experiments were, to my mind, abso- lutely conclusive ; but inasmuch as I was unable to admit with Dr. Bastian that they afforded any proof of sponta- neous generation, I followed them as soon as practicable by a series of experiments (Nature, vol. viii. p. 141) (the only ones which I myself ever made on this subject), in which I tested the influence of two new conditions, viz., of prolonged exposure to the temperature of ebul- lition, and of exposure for short periods to temperatures above that of ebullition at ordinary pressure. The ex- periments accordingly consisted of two series, in the first of which a number of retorts or flasks charged with the turnip-cheese liquid, i.e. with neutralised infusion of turnip of the specific gravity 10 17, to which a pinch of pounded cheese had been added, and sealed hermetically while boiling, were, after they had been so prepared, subjected to the temperature of ebullition for longer or shorter periods. In the second series the period of ebullition was the same in all cases, but the temperature was varied by varying the pressure at which ebullition took place. The conclusion arrived at, as expressed in the final paragraph of the paper, was, that in the case of the turnip-cheese liquid, the proneness of the liquid to produce Bacteria can be diminished either by increasing the tem- perature employed to sterilise it, or if the ordinary tem- perature of ebullition be used, by prolonging its duration. I did not think it necessary after 1873 to occupy myself further with the subject for two reasons, first, that I had accomplished my object, which was to show that as a ground for believing in spontaneous generation the turnip- cheese experiment was a failure ; but secondly, and principally, because in the meantinie the subject had been taken up by the most competent living observers, who had in every particular confirmed the accuracy of my results. I conclude this paper by referring shortly to some of these researches. The first was made by P. Samuelson under the direc- tion of Prof. Pfliigeri in 1873. Its purpose was to ascer- tain whether it is true that certain hquids can be boiled for ten minutes without being sterilized, and secondly, to determine the influence of prolonged periods of exposure. The flasks employed were charged with the neutral turnip-cheese liquid, and sealed while boiling in the way already described. Some were subjected to the tem- perature of ebullition for ten minutes, the rest for an hour, the result being that whereas those heated for the longer periods remained without exception barren, an exposure of only ten minutes was followed, in the majority of cases, by an abundant development of Bacteria? At about the same period a similar series of experiments was made under the direction of Prof. Hoppe- Seyler at Strasburg. The results were essentially the same. 2 p. 57. In the abstract of a lecture delivered at the Royal Institution, JaiiTiiary 21, 1876, similar words occur, as aUo in a letter to Nature, dated Febiuary 27, 1876, in which Dr. Tynoall, after rem.rking that the experi- ments ot Dr. Bascian, witnessed by me, wtre too scanty and too litt'e in harmony with each other to bear an inference, suggests that 1 should repeat them. . , ^ " tJeber Abiogenesis," von Paul Samuelson aus Konigsberg, Pfliiger s Archiv, vol. viii. p. 277. The paper is designated as a repon of experiments made " im Auftrag und unter der Leitung des Geh.-Kath Prof Pfiuger." I refer in the text only to those experiment- which were virtually repetitions of my own. The research actually extended o>rer awider field. 2 " Als Re uliat dieser Versuchsreihe, ergab tich eine massenhafte Ent- wickelurg von Bacterien in den meisten nur 10 Minuten lang gekochten Flussikeitsmengen nach 3-4 Tagen " {loc. cit. p. I'^i). '■ 3 " I eber die Abiogenesis Huizioga's," von Felix Putzeys aus Luttich (aus dem chemisch-physiologischen Laboratorium des Herrn Prof. Hoppe- Seyler). Pfliiger's Jirchiv, vol. ix. p. 391. In a note appended by Prof Koppe-Seyler to this paper he states that he has recommended its publica- ISlov. 29, 1877] NATURE 87 During the next year the second question which I had attempted to solve, viz., the influence of temperatures above 100° C, was taken up with much greater complete- ness by Prof. Gscheidlen, ot Breslau. ^ After a rhuini of the proofs already given by his predecessors, that certain fluids are not sterilised by boihng ; and, secondly, that as means of sterilising :uch liquids the action of prolonged exposure and that of increased temperature may be re- garded as complementary to each other, he proceeds to relate his own researches, the purpose of which was rather to fill up defects in the evidence than to establish new conclusions. The flasks employed were capable of containing 100 cub. ceniims. (three and a half oz.) ; they were charged in the usual way with the turnip-cheese liquid, and exposed for short periods in chloride of calcium baths, of which the strengths were cartfully adjusted so as to obtain the requisite temperatures. It was thereby definitely proved that whereas the germinal matter of Bacteria can stand a temperature of 100° for five or ten mmues it is destroyed by temperatures varying from 105° to i \-tant element, the following form of experiment is worthy of notice : — A tube A drawn out and closed at both enCs is fused into the open mouth of a second tube B, of which the opposite end is drawn out and closed in a similar manner. In this way a compound tube is formed wtiich is divided by a conical seotum into two chambers A and B A small knob of gla.ss having been previously introduced into the chamber b, the septum can be easily broken by shaking the tube. With tubes so prepared two experiments are made. In Experiment i, compart- ment A is charged with infusion of cheese, sealed. a.id then exposed to a temperature of 110° before it is united to the compartment B. In like manner B is charged with neutral decoction of turnip, so that when the com- pound tube is complete it coiitams clieese in one compartment, turnip in the other. If. after boiling for ten minutes, it is placed in the warm chamber its contents remain barren. In Experiment 2 the experiment is varied by simply omitting the preliminary heating of A. The compound tube is bailed as before, but now its content.-, promptly give evidence that the conditions are present for an abundant development ui Bacteria. 3 Prof. Huizinga s papers on tlie Qiirstion of Abiogenesis are four in number. The references are as follows: — PJtiiger's Archiv, vol, vii. p. 225, vol. viii. pp 180, 551 ; vol. x. p. 62 4 1 he solution employed in these experiments was neutral, and contained, in addition to the requisite inorganic salts, 2 per cent, of g'ape su^ar, o 3 per cent, of ioluble starch, 03 per cent, of peptones, and i per cent, of ammonic tartrate. As in my experiments, the fla.sks were heated in a Papin's pot, of which the temperature was 102° C. Even after half an hour's ex- posure to this temperature all the flasks became in two or three days " stark triibe undvoU Bacterien," third paper, p. 555, January, 1874. cally, whereas in his exchange of air was allowed to take place during the period of incubation, through a septum of porous porcelain. To this last objection I might per- haps have thought it my duty to answer, had it not been shown by the subsequent researches of Gscheidlen to have no bearing on the question at issue. As regards the limit of sterilisation I can entertain no doubt as to the accuracy of Huizinga's measurements, and am quite willing to accept 108° C. as the lowest temperature which could be safely employed under the conditions laid down by him. It will be understood that in bringing these facts before the Society my only purpose is to show, as I trust I have done conclusively, that the statements which Dr. Tyndall in 1876 characterised as incautious, and which he virtually invited me to retract, had been two years before confirmed in every particular by experimenters of acknowledged competence. I DIFFUSION FIGURES IN LIQUIDS^ N making some experiments on the mixture of liquids entering into another liquid at the extremity of a tube of small diameter, a phenomenon presented itself which attracted my attention as both new and singular. A certain quantity of coloured alcohol, remaining in sus- pension in the centre of a body of water, assumed, by spreading gradually out, a form resembling that of a shrub having its trunk and its branches terminated by leaf-Hke expansions. I sought to reproduce the pheno- FiG. I. —Apparatus of Prof. Martini. menon, believing at first that this mode of diffusion was purely accidental ; but the phenomenon always recurring very nearly in the same manner, I devised a mode of experimenting which enabled me to study it more advantageously. C (Fig. i) is a sort of cylindrical funnel of glass, to the neck of which is fitted a small capillary thermometrical tube T, about eight centimetres long. The capillary tube communicates by means of a caoutchouc tube a by with a » From an article in La Nature by Prot Tito Martini, of Venice. 88 NATURE \_Nov. 29. 1877 small funnel i, which may be raised or lowered at pleasure by means of its support. Pour into I a certain quantity of alcohol coloured say with a red solution of aniline. The liquid will traverse the capillary tube, from which it will flow unless prevented by compressing the india-rubber tube with a small pincers. This being done, fill with water the vessel C about three-fourths full ; then by means of a funnel whose lower extremity reaches a little below the middle of the water, introduce a liquid denser than water, a concentrated solution of sea-salt or a thick syrup, until the vessel is filled up. Sulphuric acid may also be used, and in that case a less volume of liquid will suffice. Flc. «.— Experiments of Prof. Martini on the diffusion of coloured liquids in a sirupy liquid. The liquid more dense than water will collect at the bottom of c ; and there will thus be two layers of liquid superposed, the exact separation of which may be observed after being allowed to stand for an hour. If at the end of that time we raise the funnel i to a suitable height and relieve the pincers which compress the tube a b, the coloured alcohol which flows from the extremity of the capillary tube will enter the liquid in the vessel c, forming an ascending vein which usually has a spiral form. The alcoholic vein traverses the thickest layers of the liquid and is stopped at the boundary which separates Uie denser from the less dense part which floats above. At the point where the column of coloured alcohol is arrested, it will be seen to agglomerate into a mass at first formless ; but, gradually, that mass elongates and extends, then is seen to throw out fluid threads in the form of foliage, sometimes similar to the petals of a flo-ver, sometimes analogoas to the leaves of a tree. A'ter an hour the coloured alcohol has assumed a stable and regular figure. That figure varies in form with the liquids employed ; it sometimes resembles a flower, sometimes a shrub, and sometimes it takes the form of a parasol of bright and vaporous coluurs, which add to its beauty. The figure, so far as its form is concerned, attains its maximum of developraeat three hours or more after the fluid vein begins to flow ; but after that time the leafy expansions dilate more and more, and approach each other so as to form a mass of con'inuous layers, which remain suspended in the midst of the liquid. This hap- pens even when the inflow has been arrested, either by applying the pincers to the india-rubber tube, or even by lowering suitably the funnel, I. It should also be remarked that around the vein of ascending liquid there very often forms a very fine tube, which assumes the aspect of the stalk of the flower, or rather the trunk of the liquid shrub ; from different points of that stalk ex- pansions in the form of leaves will be seen to proceed. In order that the experiments I have devised may be successful, the tube through which the coloured liquid enters the vessel ought to be capillary, the flow ought to be gentle, and the apparatus maintained in a state of complete rest. It is necessary, moreover, to be careful first to expel the air from the india-rubber tube, since air-bubbles disturb the formation of the pheno- menon. The following is a succinct resume of some of the results I have obtained with different liquids : — Colours of Aniline Solution. — -I made use of aniline red, brown, green, and violet, dissolved in alcohol, being careful that the solution was not too concentrated. The forms obtained in sugared, salted, and acidulated water, are those represented in Fig. 2, Nos. i and 2. The figures obtained resemble, as will be seen, leaf-like expansions ; the ramifications are turned downwards in sugared water (No. i) ; in salt water, on the contrary, they are always raised, and at the commencement even more so than is shown in the figure. When acidulated water is used, the aniline colours are modified by the action of sulphuric acid ; the green becomes pale yellow, the red becomes brown, and the violet acquires a beautiful green colour ; but in all cases the shrub-like figure No. 2 is formed with perfect regularity. Litmus. Aqueous Solution. — With this solu- tion we obtain in acidulated water the figure represented in No. 3 (Fig. 2), which resembles a small parasol. Looked at from above, it has the aspect of a disc from the periphery of which proceed many equidistant rays very close to each other. In the salt water the same aqueous solution gives a different figure. In general, when aqueous solu- tions are employed to form the figures a space of time is required longer than that which is necessary in the case of alcoholic solutions. Alcoholic Solution. — With this solution there are formed in salt or sugared water, figures analogous to Nos. i and 2 ; in acidulated water there is produced a shrubby appearance similar to No. 2. Lake. — The aqueous solution of lake forms in salt water a figure similar to that of No. 4 ; in acidulated Nov. 29, 1877] NATURE IJJ 89 water Fig. 3 is produced, but more delicate and more regular than that obtained with litmus. Azure Blue.—lhQ aqueous and alcoholic solutions of azure-blue or pearl form figures similar to those already described. In acidulated water we obtain a very regular spheroidal nucleus of a very dark blue, surrounded by a spheroidal layer with an inferior stem (No. 6). Cochineal. — The aqueous solution forms in acidulated water the figure No. 3, regular, like that of litmus and of lake. In salt water, cochineal, not being soluble, is precipitated and the phenomenon is not produced. Iodine.— The. alcoholic tincture of iodine forms, in sugared, salt, or acidulated water, beautiful figures almost identical with those of the colours of the aniline solution. Bichromate of Potash. — To make the experiments with bichromate of potash succeed I changed the arrangement of the experiment on account of the very great density of the solution in comparison with the density of water. I fill the vessel in the usual manner, then I place above the vessel a small funnel, fitted with a capillary tube which partly enters the liquid. The aqueous solution of bichro- mate of potash being poured into the small funnel, flows out, forming a small descending spiral, which usually is arrested in the division between the more and less dense parts of the liquid. In acidulated or salt water two very beautiful figures are. formed resembling those of Nos. 2 and 5, but reversed. The various experiments described above have been repeated several times for each colour, and I have always obtained the same results. This persistence of form shows that the phenomenon is regulated by a law which I shall seek to discover. I believe. I may conclude from these first attempts that the form of the figure depends on the liquid in which the colour is dissolved, more than on the colour itself. By employing other acids and other salts, not such, however, as precipitate the colour, it is probable that other figures would be obtained. TRACES OF EARLY MAN IN JAPAN SO much interest is felt in the origin of the Japanese, that any information regarding earlier races in Japan will interest the readers of Nature. The discovery and examination of a genuine kjockken- moedding, or shell heap, enables me to give positive evidences regarding a prehistoric race who occupied this island. Whether autocthonous or not it would of course be impossible to say. On my first ride to Tokio, in June of this year, I observed, from the car window, near a station called Omori, a fine section of a shell heap, which was recognised as such at once, from its resemblance to those I had often studied along the coast of New England. On September 16, accompanied by Messrs. Matsumura, Matsura, and Sasaki, three intelligent Japanese students, I made an examination of it, and a few days afterwards, in company with Dr. David Murray, Superintendent of Public Instruction, and Mr. Vukuyo, with two coolies to do the heavy digging, made an exhaustive exploration of it. The deposit is composed of shells of various genera, such as Vusus, Eburna, Turbo, Pyrula, Area, Pecten, Cardium, two strongly marked species of Ostrea, and curiously enough, Mya arenaria, not to be distinguished from the New England form, as well as other genera. These shells, so far as I know, still live in the Bay of Yedo. The heap is about 200 feet wide, and varies from a foot to five or six feet in thickness, with a deposit of earth above, at least three feet in thickness. It is now nearly half a mile from the shore of the Bay, though in accord- ance with the usual position of these heaps in other parts of the world, it must have been formed near the shore, and this fact indicates a considerable elevation of the land since the deposits were made. I may add that other evidences of a geological nature indicate a wide-spread upheaval in past times. The peculiarities of the typical shell-heap, such as fragments of bones, rough implements worked out of horn, and pieces of pottery, are all here. The heap, however, is marked by certain features which render it peculiar. First, the immense quantity of pottery and its diversity of ornamentation, some of it extremely ornate, but very rude. Second, the absence of bone-implements, the few found — eight or ten in number — being of horn, with the exception of an arrow-head of diminutive proportions, made of the tusk of a wild boar. All the implements are very simple ; two of them are like blunt bone awls, with the end very obtuse, and a constriction worked around the end. Another one is made from the natural termina- tion of a deer's antler. A few fragments of horn were found which had been cut off at the ends. Third, the entire absence of flint flakes, or stone imple- ments of any kind, if we except a small stone adze found near the top of the heap, and made out of a soft sand- stone. The frequent occurrence of isolated tusks of the wild boar would seem to indicate that these teeth were used for implements, and one piece of antler, having a hole in the end, is worked in the form of a rude handle. By far the most common bones found were those of the deer and wild boar, and curiously enough Steenstrup shows the same proportion in the Danish shell heaps. No human bones have yet been found. An analysis of the red pigment found on some of the pottery shows it to be cinnabar. With its removal from the shore, its elevation above the level of the sea, the absence of stone implements, and the great thickness of the earth deposits above, we have reasons for believing that the deposit is of high antiquity. Through the intelligent interest manifested by Mr. Kato and Mr. Hamao, Director and Vice-Director of the Imperial University of Tokio, every facility for a thorough investigation of these deposits will be given me. Tokio, Japan, September 21 Edward S. Morse \ NOTES It is proposed to hold the next annual meeting of the Asso- ciation for the Iniprovement of Geometrical Teaching (under the presidency of Dr. Hirst) at University College, Gower Street, on January 11, 1878, at 10.30 A.M. Four resolutions are to be submitted to the Association : — i. That in the opinion of this Association it is both reasonable and expedient that candi- dates at all examinations in elementary geometry should be required to give evidence of such ability as is necessary for the solving of easy geometrical exercises ; and that the secretaries of the Association be instructed to send a copy of this resolution to the leading examining bodies of the country. The other resolutions relate to the proposed formation of sub-committees for drawing up a syllabus of (i) Solid Geometry, (2) Higher Plane Geometry (Transversals, Projection, &c), (3) Geometrical Conies. It may be in the recollection of our readers that the report of the British Association Committee (in 1876, published at the time in Nature) was highly favourable to the work of this Association. The dissection of the Berlin gorilla was performed last week by Prof. Virchow and Prof. Ilartmann in the presence of several pro- minent Berlin physicians, and it was ascertained that the sudden death of the animal was caused by acute inflammation of the bowels, the same disease which carries off young children so rapidly. The dissection explains the cause of his previous illnesses and supplies valuable information with regard to the treatment of anthropoidal apes. The button of a glove, iron wire, and pins were found in Pongo's stomach. 90 NATURE \Nov. 29, 1877 During the past week the Emperor of Germany received a deputation of the members of the German Expedition for observing the transit of Venus, v^ho presented him with a handsomely-mounted album containing copies of all the photo- graphs taken during the transit. Bern celebrates on December 12 the looth anniversary of the death of its famous citizen, Albert Haller, who was equally renowned as physiologist, botanist, and poet. The New York Nation informs us that news has been received of the death of the Rev. James Orton, professor of natural history at Vassar College, and well known as the author of " Comparative Zoology" and "The Andes and the Amazons.'' Prof. Orton made his first expedition to South America in 1867, crossing the Andes eastward froai Peru, and descending the Napo to the MaraKon. His second expedition in 1873 was the reverse of the former one, beginnhig with the ascent of the Amazon. He was on his way home from a third expedition when he died, September 25, on board a small schooner on Lake Titicaca. He was greatly esteemed by all who knew him. The New York Tribune states that Mr, Edison, the inventor of many improvements in telegraphy, is hard at work in the endeavour to make the telephone record the sounds it transmits. His apparatus at present consists chiefly of a steel point attached to the disk of a telephone and pressing lightly on a strip of paper passed beneath the point at a uniform rate. The vibrations of the disk are thus recorded, and can be translated. Mr. Edison has already achieved some success in this attempt, but as yet finds difficulty A'ith the more delicate vibrations. The invention suggests an ultimate possibility of recording a speech at a distance, verbatim, without the need of shorthand. Not one of the designs sent in in competition for the monu- ment to Spinoza at the Hague has satisfied the judges. A new term for receiving designs will therefore be fixed. Another letter from Mr. Stanley appears in the Telegraph of Thursday last, in which he gives many interesting details of his journey down the Lualaba- Congo, but does not add essentially to what we already know from previous letters. It will be well at present to rest satisfied with the fact that he has solved a great geographical problem ; discussion will be appro, priate and to some purpose when we are in possession of the full details. In the December number of Petermann's Mittheil- ungen that keen geographer discusses the bearings of Stanley's discovery, and on the basis of the earlier letters identifies the Lualaba- Congo with the discoveries of Browne, Barth, Nachti- gal, and Schweinfurth ; but on the map which accompanies i\\i paper he carries the great river north to about 4° N. lat. In a postscript on Stanley's own map Dr. Petermann seems to think that his identifications may require modification. Dr. Petermann cannot find terms strong enough in which to speak of the merit of Stanley's work. He calls him " the Bismarck of African exploration," who has united the disjecta membra of previous explorations as Bismarck has made one great empire out of a number of isolated states. He is evidently inclined to place Stanley alongside of Columbus. The December number of Petermann's Mittheilungen contains a long paper on the Iquique earthquake of May 9 last, in which much valuable data are given on the earthquake and on the wave which was simultaneous with it over so wide a stretch of the Pacific Ocean. The Daily News correspondent at Rome writes that no news has arrived there as to the death of the African explorer, the Marquess Antinori, the inference being that he is still alive. A long letter has been received by the Italian Geographical So- ciety from Signor Matteucci who, with Signor Gessi, is bound for Inner Africa ; the two expect to be in Khartoum in the beginning of December. They were splendidly equipped before leaving Italy. Dr. Schweinfurth, the celebrated African traveller, who has been staying at Berlin since the beginning of August, will shortly return to Africa, as he finds that the European climate no longer agrees with his health . At present he has left Berlin for Weimar. At the Geographical Society, on Monday night. Commander Musters, R.N., read a paper on Bolivia, in which he gave much valuable information abaut a country, its products and its people, about which we are extremely ignorant. Commander Musters lived in the country for a considerable time. Mr. Clements R. Markham read a paper on the still unexplored parts of South America. The facts is we are almost as ignorant of Central South America as, until recently, we were of Central Africa, and there is here a practically virgin field for a second Stanley, if not indeed for Stanley himself. In a recent number we referred to the preparations v/hich are being made for Prof. Nordenskjold's expedition to the Arctic regions next summer. The Ilandels och Sjofarts Tidning of Gothen- burg publishes further details, giving the plan of the expedition as presented to the King of Sweden by Prof. Nordenskjold. We now learn that the steamer Vega is being fitted up at the royal wharves of Carlskrona, and will take provisions for two years. The Professor intends to leave at the beginning of July next, and his staff will consist of four scientific men besides himself, four Norwegian sailors who are well acquainted with the Arctic Sea, a ship's officer, eighteen marines, and a ship's doctor. The first halt will be made at the mouth of the Yenisei River ; then the expedition will proceed to Cape Tscheljuskin, and try to penetrate as far as possible in a north-easterly direction. Mr. G. J. HiNDE, of Toronto, Canada, writes us that a shock of earthquake, unusually severe for that part of the world, occurred along the valleys of the St. Lawrence and Ottawa Rivers, Lakes Champlain and St. George, and through New Hampshire, Vermont, and Western Massachusetts, at or near 2 A M. of Sunday, the 4th instant. The limits along which it has been noticed are Pembroke on the Upper Ottawa to the north-west, Montreal on the east, Boston and Providence to the south-east, and Toronto to the west. The shock appears to have been most severe on the line of the Ottowa valley between Pem- broke and Montreal, and between Ottawa city and Cape Vincent on the St, Lawrence, following in a general direction the out- crops of the Laurentian range. It was but very slightly felt at Toronto, but at Montreal the shocks are stated to have lasted twenty seconds, and to have shaken movable articles about the rooms. The following grants in aid of researches have been made this year by the Committee of Council on the report of the Scientific Grants' Committee of the British Medical Association :— Mr. Gaskell, in aid of a research on the reflex action of the vascular system and muscles and reflex vasomotor action generally, 30/. ; Mr. Langley, in aid of a research on the changes produced in the salivary glands by nerve influence,' 25/. ; Dr. Rutherford, F.R.S., for a continued research on the action of Cholagogues, 50/. ; Drs. Braidwood and Vacher, for engravings for illustrating the third report on the life history of contagium, 40/. ; Mr. Pye in aid of a continued research for the investigation of the rela- tion that the retinal circulation bears to that of the brain, 8/. 15^. ; Mr. Bruce Clarke, in aid of a continued research on syn- cope and shock, 10/. ; Mr. A. S. Lee, Heidelberg, in aid of a research on the quantitative determination of digestive products obtained by the action of pancreatic ferment upon the various albumens, 25/. ; Dr. McKendrick, Glasgow, in aid of a con- tinued research into the antagonism of drugs, 30/. ; Dr. McKen- drick, Glasgow, in aid of an investigation into the dialysis of Nov. 29, 1877] NATURE 91 blood (renewed), 10/. ; Dr. John Barlow, Muirhead Demonstra- tor of Physiology, Glasgow, in aid of an experimental investiga" tion into the changes produced in the blood-vessels by alcohol, 10/. ; Dr. Joseph Coats, Dr. McKendrick, and Mr. Ramsay, the committee upon the investigation of ansesthetics, 50/. ; Dr. McKenzie, a research on pycemia, 25/. ; Mr, Callender, F.R. S., Dr. J. Burdon Sanderson, F.R.S., Dr. T. Lauder Brunton, f.R.S., and Mr. Ernest Hart, the committee appointed for the investigation of the pathology and treatment of hydrophobia, 100/. Total, 413/. I5J-. Telegraph warnings are to be employed all over Paris for giving alarms of fires to all the fire-engine stations. The alarm is given by breaking a small|pane of glass facing the streets, being a variation of the system employed on railways for signalling the engine-driver or guard. In the November session of the Berlin Geographical Society Baron v. Richthofen was re-elected presideat. The evening was chiefly occupied by an address from Dr. Nachtigal, on the results of Stanley's lately accomplished expedition, which he regarded as the most prominent event among ater African explorations. Prof. Orth gave a short description of a new met hod of cartography. Lieut, de Semell6 has intimated to the Paris Geographical Society that he intends to cross Africa5from west to east, ascending the Niger and Binue, making for Lakes Albert and Victoria, and reaching the east coast at Mombasa or Malinda. He states that he has already obtained sufficient resources. The chemists of Berlin have been occupied lately in analysing the wares of the wine merchants, and no little excitement has been caused by the discovery that the entire stock of one of the largest houses dealing in wines for medicinal purposes, consisted entirely of artificially prepared mixtures of spirit and sugar solutions, flavoured with various herbs. At Leipzig a " General German A nti- Adulteration Society'' has been formed, which has for its main object the prevention of the adulteration of food. A periodical is to appear, or has already appeared, as the organ of this society. At some fifty other German towns branch societies are being established. All political or religious matters are excluded from the programme of the society, while one of its statutes prescribes the special prosecution of the makers and sellers of so-called secret remedies and medicines. In evidence of the interest "now being ^taken by Spain in scientific subjects we may draw attention to the Boletin de la Institucion litre de Ensenanza (Madrid, 1877), the first five numbers of which, from March 7 to June 17, now lie before us. We notice Geometria y morfologia natural, Prof. De Linares ; Investigacion de los propiedades opticas, Prof, Calderon ; La religion de los Celtas sspailoles, Prof. Costa; Principios y Definiciones de la Geometria, Prof. Jimenez ; Precipitacion de los melales puros por los sulfuros naturales, Prof. Quiroga, There are accounts of papers read at meetings under the headings " Resumenes de Enseiianzas," and " Conferencias," The Boletin is in shape not quite so large as Nature, and each number contains four pages. The Minister of Instruction in the cabinet chosen by Marshal MacMahon last week is M. A. E, A, Faye, the well-known astronomer, who is spoken of as Leverrier's probable successor. M. Faye is at present in his sixty-third year, and is chiefly known through his discovery of the comet named after him, in 1843. Since that time he has devoted his attention principally to the consideration of the problems of physical astronomy, the solar constitution, &c. His most important works are *' Lemons de Cosmograp^ie," 1852 ; and a translation of Humboldt's '•Cosmos." M, Faye is probably the best known in what is ironically termed the cabinet des inconnus. French politics allure an unusually large number of scientific men. Naquet, the chemist, is now a leader of the radical wing of the Republican party, Dumas and Scheurer-Kestner are life members of the senate, and Wurtz was proposed as a candidate for the senate a few weeks since. The communication of the city of Moscow with the river Volga, leaving the railway out of account, was, up to the present, only possible in the spring of each year, on account of the shallowness of the Moskwa River. The boats were drawn by horses from Moscow to Kolomna on the river Oka, which falls into the Volga at Nishni-Novgorod, and this means of commu- nication, on account of the great time it occupied, not to mention its cost, was a very imperfect one. A series of locks has recently been constructed on the Moskwa River, and tug steamers are now running between the capital and the Oka. We have already referred to the proposed introduction of the telephone into the German tele^iraphic service. Dr. Stephan, the enterprising Postmaster-General of the German empire, who has brought the German postal service to such efficiency, and fairly created the present international telegraphic system, ap- pears to have definitely settled the question of the practicability of the general introduction of the new method. For the past few weeks the telephone has been in constant use between the General Post Office and the General Telegraph Office in Berlin, and has superseded the telegraphic communication between Berlin and some of the neighbouring villages. The results have been so satisfactory that a few days since a consultation of leading tele- graphic officials was held to make arrangements for the establish- ment of a large number of telephonic stations. Since the equip- ment of these stations is so inexpensive, and the long and cos'.ly preliminary training of a telegrapher is avoided, it can easily be understood with what readiness the new invention is put into practical use. Interesting in this connection is the recent adoption of the telephone by Prince Bismarck. He has caused, as we stated last week, the establishment of a telephonic means of communication between the Chancellor's office in Berlin and his country residence at Varzin, in Pomerania, 230 miles distant ; and finds that he is perfectly able to give instructions and receive reports without leaving h's favourite castle. No subterranean wires, but the ordinary telegraphic wires on poles, are used for this purpose. A series of researches on the compressibility of liquids has recently been described by M. Araagat in the Annates de Chimie et de Phydque. Among other results, the compressibility is found to be far from depending on the volatility of liquids, as might be supposed. The presence of sulphur, chlorine, bromine, and probably also iodine, tends to diminish the compressibility (a fact sufticiently explained by the corresponding increase of density). With regard to alcohols, the compressibility diminishes from the first member of the series, methylic alcohol, at least at 100°. At 14° common and methylic alcohol have nearly the same compressibility ; and at zero the common alcohol is perhaps more compressible than methylic alcohol. Of the ethers, ethyl- acetic ether is more compressible at 14° and at 100° than methyl- acetic ether (an inverse order to that of the densities, which decrease as you rise in the series. With regard to hydrocarbons, the compresdbility decreases regularly both at ordinary tempera- ture and at 100° as you descend in the series. A MICROSCOPICAL study has recently been made by M. PriK lieux, of a disease of fruits, and especially of pears, which consists in the appearance of spots, then of crevices, issuing in complete disorganisation. From the facts described, it appears that the cause of this evil is a fungus, the spores of which are developed on the skin of the fruit with the appearance of a thin filarncu". At a certain ti^nc this filament penetrates ilie cpider- 92 NATURE \_Nov. 29, 1877 mis and produces a mycelium, which develops in the very mass of the fleshy tissue. Later there appear, in addition, fructiferous filaments, which bear about twenty-five spores each. The cells of the fruit, on passage of the parasite, are destroyed, and it is thus that the crevices are formed. The diffusion which takes place between two gases separated from each other by an absorbent film (f.^., a soap film) was studied a short time ago by Prof. Exner, of the Vienra Aca- demy. He has recently extended his inquiry to the case of vapours from easily volatile liquids, using the same apparatus as for permanent gases. The experiments were made with sulphide of carbon, chloroform, sulphuric ether, benzine, alcohol, and oil of turpentine, and they show that the diffusion from such vapours follows the same laws as those of gases, i.e., that it depends both on the coefficient of absorption of the film and on the density of the gas being directly proportional to the former, and inversely proportional to the square root of the latter. Thus it appears that the greater or less distance of a gas from its liquefaction point has at least no influence on this kind of diffusion. It is reported that Herr Josef Albert, the eminent Munich photographer, has made the highly important invention of pho- tographing the natural colours of objects by means of a combina- tion of the ordinary photographic process with a photographic printing press constructed by the same gentleman some time ago. The images are stated to be so perfect that not the least improve- ment with the brush is required, as the finest shades of colours are faithfully reproduced. The secret of the invention is said to be based on the separation of white light into yellow, blue, and red rays, and in the artificial application of the same colours in the printing press. The first negative is taken upon a plate which is chemically prepared in such a manner that it only receives the yellow tints or shades of the object ; this is then passed through the printing press, the roller of which is impreg- nated with a yellow colouring matter. On the print only the yellow tints reappear more or less distinctly ; the object is then again photographed, and this time a negative is prepared^which only receives the blue shades and tints ; a second printing press has its roller impregnated with some blue colour, and the plate of course gives a print with only the blue tints reproduced. In the same manner a third print is obtained which only shows the red shades and tints. The final manipulation now consists in printing the three images upon the same plate, when the three colours intermingle and the natural colours and shades of th; objects are obtained. We need hardly point out the enormous importance of this invention. A PAMPHLET just published by the Director of the Paris National Library contains some interesting statistical data re- specting one of the finest libraries in the world. It has been found that the library contains 86,774 volumes on catholic theology, 44,692 volumes on the science of languages, 289,402 volumes on law, 68,483 volumes on medicine, 441,836 volumes on French history, and 155,672 volumes of poetry. The works on natural science are not yet catalogued. During 1876 the library received no less than 45,300 French additions and purchased 4,565 foreign books. The additions to the Zoological Society's Gardens during the past week include two Black-eared Marmosets {Hapale penicillaia) from South America, presented by Miss Quain ; a Black-backed Jackal (Canis mesomeles) from South Africa, presented by Capt. Fulton, s.s. Tay mouth Castle ; a Common Boa {Boa constrictor) from South America, presented by Miss Alice Leith ; a Brown Tree Kangaroo {Dendrolagus inustus) from New Guinea, a Slow Loris {Nycticebus tardi^radiis) from Malacca, a River Jack Viper ( Vipera rhinoceros) from West Africa, purchased ; a Green '^lovkf-y [Ccrcofihecus callitric/ius) from West Afiica, deposited. 1 THE LIBERTY OF SCIENCE IN THE MODERN STATED II. T is easy to say: "A cell consists of small particles, and these we call plastidules ; plastidules, however, are composed of carbon, hydrogen, oxygen, and nitrogen, and are endowed with a special soul ; this soul is the product or the sum of the forces which the chemical atoms possess." Indeei this is possible ; I cannot judge of it exactly. This is om of those points which are yet unapproachable for me ; I feel there like a navigator who gets upon a shallow, the extent of which he cannot guess. But yet I must say that before the properties of carbon, hydrogen, oxygen, and nitrogen are defined to me in such a manner that I can understand how, through their combination a soul results, I cannot admit that we are justified in introducing the plastidule soul into the educational programme or to ask gene- rally of every educated min that he should recognise it as a scientific truth to such a degree as to operate with it logically, and to base tiis conception of the universe upon it. This we may really not ask. On the contrary, I think that before we designate such theses as the expression of science, before we say this is modern science, we ought first of all to complete a whole series of lengthy investigation'. We must therefore say to the schoolmasters, do not teach this. This, gentlemen, is the re- signation which in my opinion, those ought to exercise who deem such a solution in itself to be the probable end of scientific investigation. We can certainly not differ on that point for a moment, that if this doctrine of the soul were really true it couli only be confirmed by a long series of scientific investigations. There is a series of events in the field of the natural sciences, by which we can show, for how long certain problems are in suspense, before it is possible to find their true solution. If this solution is found at last, and found in a direction of which there was a presentiment perhaps centuries ago, it does not follow that during those times which were occupied only by speculation or presentiment the problem might have been taught as a scientific fact. Prof. Klebs spoke of contapum animattim the other day, i.e. the idea that in diseases the transmission takes place by msans of living organisms, and that these organisms are the causes of contagious diseases. The doctrine of conta^ium animtuvi loses itself in the obscurity of the middle ages. We have had this name handed down to us by our forefathers, and it is very prominent in the sixteenth century. Certain works of that period exist, which put down contagium animatum as a scientific dogma with the same confidence, with the same kind of justi- cation, as nowadays the plastidule soul is set up. Nevertheless the living causes of diseases could not be found for a long time. The sixteenth century could not find them, nor could the seven- teenth and the eighteenth. In the nineteenth century we have begun to find some contagia animata bit by bit. Zoology and botany have both contributed to them : we have found animals and plants which represent contagia, and a special part of the knowledge of contagia has been absorbed into zoology and botany, quite [in the sense of the theories of the sixteenth century. But you will already have seen from the address of Prof. Klebs that the end of proofs has not yet ended. However much we may be disposed to admit the general validity of the old doctrine, now that a series of new living contagia have been found, now that we know cattle disease and diphtheria to be diseases which are caused by special organisms, still we may not yet say that now all contagia or even all infectious diseases are caused by living organisms. After it has appeared that a doctrine, which was formulated already in the sixteenth century, and which has since obstinately emerged again and again in the ideas of men, has at last, since the second decade of the present century, obtained more and more positive proofs for its correctness, we might really think that no v it was our duty to infer, in the sense of an inductive extension of our knowledge, that all con- tagia and miasmata are living organisms. Indeed, gentlemen, I will admit that this conception is an extremely probable one. Even those investigators, who have not yet gone so far as to regard the contagia and miasmata as living beings have yet always said that they resemble living beings very closely, that they have properties which we otherwise know in living beings only, that they propagate their kind, that they increase ' Address delivered at the Munich meeting of the Gennaa Association, by Prof. Rudolf Virchow, of Berl'n. Continued from p. 74. Nov. 29, 1877] NATURE 93 and are regenerated under special circumstances, that, indeed, they appear like real organic bodies, — these men, nevertheless, have waited, and rightly, until the proof of their being living organisms was furnished. And thus caution commands reserve even now. We must not forget that the history of science presents a number of facts which teach us that very similar phenomena may happen in a very different manner. When fermentation was reduced to the presence of certain fungi, when it was known that its begin- ning was closely connected with the development of certain species of fungi, then it w as really very obvious to imagine that all processes related to fermentation happen in the same way ; I mean all those processes which are comprised under the name of "catalytic," and which occur so frequently in the human and animal body as well as in plants. There were, indeed, some scientific men who imagined that digestion, which is one of the processes which closely resemble the fermentative ones, was brought about by certain fungi which occur frequently (in the special case of cattle the question has been practically discussed), and which were supposed to cause digestion in the stomach in the same way as the fermentation fungi cause fermentation elsewhere. We now know that the digestive juices have absolutely nothing to do with fungi. Much as they may possess catalytic propertie-:, we are yet certain that their active substances are chemical bodies which we can extract from them, which we can isolate from their other component parts, an i which we can cause to act in the isolated state free from any admixture of living organisms. If the human saliva has the property of being able to change starch and c'extrine into sugar ita the shortest time, and if every time we eat bread this new formation of "sweet" bread takes place in our mouth, then no fungus takes part in this nor any fermentation organism, but there are chemical substances which, much in the same way as it happens in the interior of the fungus, bring about chemical change in matter. We see, therefore, that two processes which are extremely similar, the one in the interior of the feraieiitation fungus and the other in the process of human digestion, are brought about in different ways ; the same process in the one instance is connected with a certaia vegetable organism, while in the other it takes place without any such organism and simply through a liquid. I should consider it a great misfortune if we were not to con- tinue in the same way as I have done now, to examine in each single case whether the supposition which we make, the idea which we have formed and which may be highly probable, is really true, whether it is justified by facts. With regard to this I would remind you that there are cases also amongst the infectious diseases where most undoubtedly a similar contrast exists. My friend. Prof. Klebs, will no doubt pardon me if I, even now, in spite of the recent progress which the doctrine of infecting fungi has made, still remain in my reserve, and that I only admit that fungus which has been proved by demonstration, while I deny all the other fungi as long as I do not hear of facts which attest them. Amongst infectious diseases there is a certain group which are caused by organic poisons — I will only mention one of them, which," according to my opinion, is very instructive — I mean the poisoning by a snake-bite, a very cele- brated and most remarkable form. If this kind of poisoning is compared with those kinds of poisoning which are generally called infectious diseases (infection does not signify much else than poisoning), then we must admit that in the courses both cases generally take the greatest analogies exist. With regard to the course of the illness nothing would oppose the supposition that the total sum of pheiaomena which occur in a human body after a snake-bite, were caused by fungi which entered the body and which produced certain changes in different organs. Indeed we know certain processes, septical ones, for instance, wheie phenomena of a completely similar nature occur, and it cannot be denied that certain forms of poisoaing by snake-bite resemble certain forms of septical infection ai much as one egg resembles another. And yet we have not the least cause to suspect an importation of fungi into the body in the case of snake bite, while in the case of septic processes we, on the contrary, acknowledge and recognise this importation. The history of our natural science has numerous examples, which ought always to cause us more and more to confine the validity of our doctrines in the most stringent manner to that domain only in which we can actually piove them, and that we do not by way of induction, proceed so far as to extend doctrines immeasurably which have only been proved for one or several cases. Nowhere the necessity of such a restriction has become more apparent than on the field of the theory of evolution. The question of the first origin of organic beings, this question which also forms the basis of progressive Darwinism, is an extremely old one. It is not known at all who first tried to find the different solutions for it. But if we remember the old popular doctrine, according to which all possible beings alive, animals and plants, could originate from a clod of clay — from a little clod under circumstances — then we ou^ht to remember at the same time that the celebrated doctrine of goteratio ceqiiivoca, of epigenesis, is closely connected with it, and that it has been a common idea for thousands of years. Now with Darwinism the doctrine of spontaneous generation has been taken up again, and I c mnot deny that there is something very seductive in the idea of closing the theory ( f descent in this way, and, after the whole series of living forms has been constructed, from the lowest protozoa upwards to the highest human organism, to connect this long series v/ith the inorganic world as well. This corresponds with that direction to generalise, which is so entirely human, that it has found a place in the speculation of man- kind at all times, backwards to the most obscure periods. We have the undeniable desire not to separa'e the organic world from the universe, as a something which is divided from it, but rather to insure its connection with the universe. In this sense it is pacifying if one can say, the atom-group carbon and company — this is perhaps speaking too collectively, but ye: it is correct, since carbon is to be the essential element — therefore, this asso- ciation, carbon and company, has at some special time separated itself from the ordinary carbon and founded the first plastxdule under special circumstances, and continues to found it in the pre- sent. But in the face of this we must mention that all real scientific knowledge of the pheaomena of life has proceeded in an opposite direction. We date the beginning of our real knowledge of the development of higher organisms from the day when Harvey pronounced the celebrated phrase, " Omne vivum ex ovo," every living being comes from an egg. This phrase as we now know, is incorrect in its generality. To-day we can no longer recognise it as a fully justified one ; we know that, on the contrary, a whole number of generations and propagations exist without ova. From Harvey down to our celebrated friend Prof, von Siebold, who obtained the general recognition of parthenogenesis, there lies a whole series of increasing restriction?, all of which prove that the phrase, " Omne vivum ex ovo " was incorrect speaking in a general sense. Nevertheless, it would bathe highest ingratitude if we were not to acknowledge that in the opposition, which Harvey assumed against the old gemratio crquivoca, the greatest progress was made which has been made by science in this domain. Later on a great number of new forms were known, in which the propagation of the different kinds of living beings is going on, in which new individuals originate— direct separation, gemmation, metagenesis. All these forms, parthenogenesis included, are data which have caused us to give up every single (cinheitlicke) system for the generatioa of organic individuals. In place of a single schema we now have a variety of data ; we have no uniform system left by which we could explain once for all how a new animal being begins. Generatio aquivoca, which has been disputed and refuted as many times, nevertheless faces us again and again. It is true that not a single positive fact is known which proves that generatio wquivoca has ever occurred, that spontaneous genera- tion has ever taken place in such a way that inorganic masses, let us say the association carbon and company, have ever spon- taneously developed into an organic substance. Nevertheless, I admit that if we indeed want to form an idea how the first organic being could have originated by itself, nothing remains but to go back to spontaneous generation. This is clear. If I do not want to suppose a creation-theory, if I do not want to believe that a special creator existed, who took the clod of clay and blew his living breath into it, if I want to form some conception in my own way, then I must form it in the sense of generatio tcquivoca, Tertium tton datur. Nothing else remains if once we say " I do not admit creation, but I do want an explanation." If this is the first thesis, then v,-e must proceed to the second and say " Ergo, I admit generatio csquiuoca." But we have no actual proof for it. Nobody has ever seen generatio crquivoca occurring in reality, and everyone who maintaii>ed that he had seen it, has been refuted, not by theologians indeed, but by naturalists. I mention this, gentlemen, in order to let our impartiality appear in the riglit light, and this is very necessary at times. We always have our weapons in ourselves and about us, to fight against that which is not justified. I therefore say that I must admit the theoretical justification 94 NATURE \_Nov. 29, 1877 of such a formula. Whoever will have a formula, whoever says " I absolutely want a formula, I wish to be perfectly at one with myself, I must have a coherent conception of the universe," must either admit gcncratio (tqi/ivoca pv creation j there is no other alternative. If we want to be outspoken we may indeed own th^t naturalists may have a slight predilection for genei-atio cvquivoca. It would be very beautiful if it could be proved. But we must admit that it is not yet proved. Proofs are still wanting. I f any kind of proof were to be successfully given we would acquiesce. But even then it would have to be determined first, to what extent we could adnait generatio aquivoca. We should quietly have to continue our investigations, because nobody will think that spontaneous generation is valid for the totality of organic beings. Possibly it would only apply to a single series of beings. But I believe we have time to wait for the proof. Whoever remembers in what a regrettable manner, quite recently, all attempts to' find a certain ba-,is for generatio ccqidvoca in the lowest forms of the transition fro;'?:! the inorganic to the organic world, have failed, should c ns'der it doubly dangerous to demand that this ill-reputed doctrine should be adopted as a basis for all human conceptions of life, I may, doubtless, suppose that the story of the Bathyhius has become known to nearly all educated persons. With this Bathybiiis the hope has Egain vanished that generatio ceqtnvoca can be prove 1. I think, therefore, that with regard to this first point, the IJoint of the connection between the organic and the inorganic, we must simply own that in reality we know nothing about it. We may not set down our supposiiion as a certainty, oar problem as a dogma ; that cannot ba permitted. Just as in the progress of the doctrines of evolution it has been far more certain, more fertile, and more in accordance with the progress of accredited natural science, to analyse the original single doc- trine part by part, we shall also have first to keep apart the organic and inorganic thinn;s in the old well-known analysing vay, and not to throw them together prematurely. Nothing, gentlemen, has been more dangerous to natural science, nothing has done more harm to its progress and to its position in th^ opinion of nations than premature syntheses. While laying stress upon this, I would point out specially how our Father Oken was damaged in the opinion not only of his contemporaries, but also in that of the following generation, because he was one of those who admitted syntheses into their conceptions to a far greater extent than a stricter method would have allowed. Do not let us lose the example of the natural philosophers j do not let us forget that every lime that a doctrine which has assurced the air of a certain, well-founded, and reliable one, of one which claims general validity, turns out to be faulty in its outlines, or is found to be an arbitrary and despotic one in essential and great points, then a great number of men lose their faith in science entirely. Then the reproaches begia — "You are not sure even yourselves; your doctrine, which is called truth to-day, is a falsehood to-morrow ; how can you demand that your doctrine shall become the object of instruction and of the general consciousness ? " From such experiences I take the warning that if we wish to continue to claim the attention of all we must resist the temptation of pushing our suppositions, our merely theoretical and speculative structures into prominence to such a degree that from them we would construct the concep- tion of the whole remaining universe. (To be continued.') THE METEOR A METEOR of unusual brilliancy was seen on the evening of -^*- Friday, the 23rd inst., from various parts of the kingdom. Mr. F. A. Buxton writing to us from Hertford states that he saw it two miles north of that town at 8.26 P.M. He says : — "I was attracted 'ry its glare notwithstanding the moonlight, and saw it moving vertically downwards. I could not accurately observe its path, but it passed, nearly or exactly, over a small star, just visible in the moonlight, which I think is tt Herculis, and di- appeared suddenly before it reached the horizon, in about N.P.D. 60 and R. A. i6"40. By comparing notes with another observer (half a mile north of Hertford) it appears to have been visible much nearer the zenith than I had seen it ; probably I saw the last \^ of its path. From the apparent slowness of its motion and complete absence of sound I gather that it was far off. My guess at the moment was fifty miles. In consequence of its brightness its apparent diameter was probably illusory. It attained two maxima of splendour, one about over the star named, the other at its disappearance. Scarcely any ' trail ' was left ; what there was almost immediately vanished. " Mr. T. Mellard Reade writes that he saw it from Blundell- sands, Liverpool, at 8.20 P.M. Looking up he saw a splendid broad streak of blue light terminating in a ball of red fire rushing across the sky ja a north-westerly direction. The first flash seemed directly overhead ; if so, Mr. Reade states, the meteor must have travelled through at least 45°. Shortly afterwards the moon being intensely bright and a shower coming on from the west, across the sea a most splendid "mo jn " rainbow made its appearance, finishing as a perfect arch of vivid colours with a second and a perfect bow above it. Mr. W. B. Ferguson writes from Edinburgh that while walking down Princes Street about 8-25 P.M. he saw a most brilliant meteor which appeared to fall almost vertically and burst with great brilliance appirently just behind the castle. Its direction from where he observed it wa? 10^ west of south. Mr. p. H. Dance, writing from Manor House, Ardwick, Man- chester, gives the time as 8h. 25 n. p.m. Greenwich mean time. The meteor, he states, appea.red to come from the constellation Cassiopeia, and after travelling in a direction a little to the west of north, finally hurst behind a cloud about thirty degrees above the horizon. The apparent size of the meteor was considerably greater than that of Mars during the late opposition, and the light which it emitted was intensely bright and of a bluish-greea colour, leaving a decidedly red impresfion on the retina. The period of visibility would be about five seconds, and the sparks in the train were also visible for some seconds. Mr. Plant, the Curator of the Salfbrd Museum, observed the meteor at the same time, visible to the narth of Manchester. Di'. S. Drew, of Sheffield, saw it at about 8.30 p.m. He gives the apparent diameter as two minutes ; path, from the square of Pegasus to near Altair ; motion, slow ; shape, at first globular, afterwards elongate I, with tail. It then appeared to break up. Colour, at first blue-green, afterwards ruddy ; light, brilliant. He heard no sound accompanying the meteor, and from the absence of sound and slow apparent motion, he infers the real distance and size of the bolide to have been great. Dr. Drew wa<;, at the time of observation, a little to the west of the town of Rotherham. Several correspondents write to the Tifiies describing what they saw of this remarkable meteor, for it is evidently the same body which has been seen by the various observers. The Liver- pool correspondent of the Times saw it about 8'30. " A large ball of fire shot from the sky, exploding and throwing off in- numerable variegated sparks as it descended in a northerly direction. The track of sparks gave the meteor the appearance of a brilliant comet with a long tail. Some spectators state that they heard the hissing noise made in its course, and othfers allege that it descended into the water near the bar of the Mersey with a great noise, sending up a column of steam and spray." Mr. Donald Mackay saw it from Victoria Street, London, shortly before 830 P.M. "It travelled Avith great rapidity for about 20° from the zenith to the horizon, bursting in a white ball as large as twelve of the planet Mars in one, lighting up all the houses surrounding Victoria Street, the point of observation, and leaving a large tail behind of the shape of a spear-head, with all the colours of the rainbow in it." The Rev. J. Hoskyns-Abrahall writes from Combe Vicarage, near Woodstock, that about 8.20 the northern sky was suddenly lighted up with a glow that outshone that spread over the south-eastern sky by a moon nearly full. "Looking northwards I saw a globular meteor of a pale orange colour dejcending perpendicularly. Its apparent size was scarcely less than that of the moon. Just above the slope on which I was, and seemingly not half a mile off, it burst into huge fragments, which flared forth with a fierce, lightning-like, reddish glare, and scattered sparks of surpassing splendour." Mr. D. Aldred writes from Milford, Derby, to the same effect. He saw the meteor about six miles north of Derby, about 8.25. " It was almost due north, and travelling from the zenith to the horizon, the point of dispersion being about 45° above the north point of the horizon. In shape it was conical, the greatest breadth about one and a half times the diameter of the moon, It left a trail of considerable length, and the colours detached were of most remarkable brilliancy." " R. ]\I. C." writes from Cathedine, Brecknockshire, giving the report of two reliable witnesses who were walking in an easterly direction at 8.25 p.m. Looking back, the moon being at the time obscured by a cloud, tliey tav a ball of the rao-.l intense white li^ht, "about the si^j of a caimou-bali," travers- ]S!ov. 29, 1877] NA TURE ing a space between two clouds, leaving behind it a fiery track of red. A Worcester correspondent gives the tirtie as 8.20. He describes the colour as brilliant blue and orange, and behind v*as a streaming trail of brilliant sparks, which remained visible for a few seconds after the brighter light had disappeared. UNIVERSITY AND EDUCATIONAL INTELLIGENCE Cambridge. — At a Congregation on November 22, Ihi; University seal was ordered to be affixed to a letter of thanks to his Grace the Chancellor of the University for his munificent gift of a complete apparatus of scientific instratrtents for the Cavendish Laboratory. A meeting of the members of the University to consider the propriety of securing a personal memorial of Dr. Darwin, was held on Monday in the combination room of Christ's College, the Rev. Dr. Cartmell, Master of the College, presiding. It w^as proposed by Prof. Humphry and seconded by Prof. Fawcett, *' That it is desirable that^lhe University ghould.'possess a personal memorial of Mr. Charles Darwin, LL.D." Proposed by Prof. Newton and seconded by Mr. Piele, of Christ's, "That the members of the University now present form themselv.es into a committee, with power to add to their number, for the purpose of collecting subscriptions from members of the University to carry out the foregoing resolution." Proposed by Prof. Liveing, seconded by Mr. J. W. Clark, " That Mr. A. G. Dew-Smith, of Trinity College, be treasurer and secretary to the committee, and be authorised to receive subscriptions." It was understood that the memorial should assume the form of a portrait, and about 75/. was subscribed in the room. Edinburgh. — The subscriptions to the Edinburgh University Extension Fund now amount to 82,000/., and Government has now promised to add 80,000/. to the amount on condition that 25,000/. is raised by public subscription, of which the sum of 10,000/. must be subscribed by December 31st next. The University Professors at Edinburgh have already contributed among themselves 5,360/. towards the additional 25,000/. required. St. Andrews. — Lord Selborne has been elected Lord Rector of this University. The students had much difficulty in getting any eminent man to allow himself to be nominated, and it was only on the day previous to the election that it was resolved to pit Lord Selborne against the Right Hon. Gathorne Hardy. Prof. Alleyne Nicholson has been appointed Swiney Lecturer on Geology by the Trustees of the British Museum. Leipzig. — Prof. Leuckhart^ the newly-elected Rector of the University, was installed into the duties of the office on October 31, and delivered on the occasion an able addre3s " On the Deve- lopment of Zoology up to the Present Time, and its Importance." The students already nunber nearly 3,200, an attendance, as usual, far above that of any other Garmin university. Amsterdam. — The new University of Amsterdam has lately made a most flattering offer to Prof. Gegenbaur, of Heidelberg, which has, however, been declined. Bergen. — It is intended to establish a new university in the Norwegian tovvn of Bergen. Eighty thousand crowns liave already been subscribed towards this object. SOCIETIES AND ACADEMIES London Mathematical Society, November 8.— Lord Rayleigh, F.R.S., president, in the chair. — The following were elected to form the Council during the session : — President : Lord Rayleigh, F.R.S. Vice-Presidents: Prof. J. Cleik Maxwell, F.R.S., Mr. C. W. Merrifield, F.R.S., Prof. H. J. S. Smith, F.R.S. Treasurer, Mr. S. Roberts. lion. Secretaries : Messrs. M. Jenkins and R. Tucker. Other members, Prof. Cayley, F.R.S., Mr. T. Cotterill, Mr. J. W. L. Glaisher, F.R.S., Mr. H. Hart, Dr. Henrici, F.R.S., Dr. Hirst, F.R.S., Mr. Kempe, Dr. Spottiswoode, F.R.S., Mr. J. J. Walker.— Prof. Cayley made two communications, on the function <^ {x) = ^-"^ "^ , (a sin- cx -k- a gttlarly neat expression was got for <^" (;ir), the late Mr. Babbage had considered the matter in 1813), and on the thcta functions. — Mr. Tucker read a portion of a paper by Mr. Hugh MacCoU (communicated by Prof. Crofton, F.R.S.) entitled the calculus of equivalent statements. A short account of thi? analytical method has been given in th? July and November numbers (1877) of the Educational Times, under the name of Symbolical Language. The chief u^e at present made of it is to determine the new limits of integration when we change the order of integration or the variables in a multiple integral, and also to determine the limits of integration in questions relating 1 1 probability. This object, the writer asserts, it will accomplislj with perfect certa'nty, and by a process almost as simple and mechanical as the ordinary operations of elementary algebra. — The president read a paper on progressive waves. It has often been remarked that when a group of waves advance ititiJ still w^ter the velocity of the group is less than that of the individual waves of which it is composed ; the waves appear to advance through the group, dying away as they approach its anterior limit. This phenomenon seems to have been first explained by Prof. Stokes, who regarded the group as formed by the super- position of two infinite trains of waves of equal amplitudes and of nearly equal wave-lengths advancing in the same direction. The writer's attention was called to the subject about two years since by Mr. Froude, and the same explanation then occurred to him independently. In his work on " The Theory of Sound " (§ 191), he has considered the question more generally. In a paper read at the Plymouth meeting of the British Association (afterwards printed iii Nature), Prof. Osborne Reynolds gave a dynamical explanation of the fact that a group of deep-water waves advances with only half the rapidity of the individual waves. Another phenomenon (also mentioned to the author by Mr; Froude) was also discussed as admitting of a similar expla- nation to that given in the present paper. A steam launch moving quickly through the water is accompahied by a peculiar system of diverging waves, of which the most striking feature is the obliquity of the line containing the greatest elevation of successive waves to the wave-fronts. This wave-pattern may be explained by the superposition of two (or more) infinite trains of waves, of slightly differing wave-lengths, whose direction and velocity of propagation are so related in each case that there is no change of position relatively to the boat. The tilode of com- position will be best understood by drawing on paper two sets of parallel and equidistant lines, subject to the above Conditions, to represent the crests of the component trains. In the case of twj trains of slightly different wave-lengths, it may be proved that the tangent of the angle between the line of maxima and the wave- fronts is half the tangent of the angle between the wave-fron!s and the boat's course. — Prof. Clifford, F.R.S., communicated three note', (i) On the triple generation of three-bar curves. // one of the three-bar systems is a crossed rhomboid, the other two are kites. This follows from the known fact that the path of the moving point in both these cases is the inverse of a conic. Bat it is also intuitively obvious as soon as the figure is drawn, and thus supplies an elementary proof that the path is the inverse of a conic in the case of a kite, which is not otherwise easy to get. (2) On the mass-centre of an octahedron. The construction was suggested by Dr. Sylvester's construction for the mass centre of a tetrahedral frustum. (3) On vortex-motion. The problfem solved by Stokes as a general question of analysis, and subse- quently by Helmholtz for the special case of fluid motion may be stated as follows : given the expansion and the rotation at evfery point of a moving substance, it is required to find the velocity at every point. The solution was exhibited in a very simple form. Zoological Society, November 6. — Mr, X. Grote» vice- president, in the chair. — A letter was read from Mr. R. Trimen, containing remarks on the African species of Sarcidiornis. —A letter was read from Mr. A. O. Hume, containing some remarks on Mr. Howard Saunders' recent p.iper on the Sterninae. — The secretary exhibited, on the part of Mr. Geo. Dawson Rowley, an egg of Pauxis galeata, laid by a black female. — Prof. W. II. Flower, F.R.S,, read a paper entitled "A Further Contribution to the Knowledge of the existing Ziphioid Whales of the Genus Mesoplodon, containing a Description of a Skeleton and several Skulls of Cetaceans of that Genus from the Seas of New Zea- land."— A communication was read from Lieut. -Col. R. H. Bed- dome, containing the descriptions of three new species of reptiles from the Madras Presidency. These were proposed to be called Oligodon travancoricum, GymHedactylusjeyporensis, and Bufo tra- vancoriiUs. — A communication was read from the Marquis of Tweeddale, F.R.S., containing an account of a collection of 96 NATURE \TSIov. 29, 1877 birds made by Mr. A. H. Everett in the Island of Luzon, Philip- pines. Three new species were named Megalurus ruficeps, Dic(Bum xanthopyg'mm, and Oxycerca eva'etti. — Mr. D. G. Elliott read some remarks on Felis tig7-ina,YjXX. , and its synonomy, show- ing that F. mitis, F. Cuv., andi^. macrura, Pr. Max., are iden- tical with that species. — Prof. Garrod, F.R.S., read a paper on some points in the visceral anatomy of the rhinoceros of the Sunderbunds {Rh. sondiacus). — A second communication from Prof. Garrod contained a note on an anatomical peculiarity in certain storks. — Mr. Edgar A. Smith read a paper in which he described some shells from Lake Nyassa, and a few marine species from the mouth of the Macusi River, near Quillimane, on the East Coast of Africa. — A communication from Dr. O. Finsch contained the description of a new species of petrel from the Feejee Islands, which it was proposed to name Procellaria albigularis. — A second communication from Dr. Finsch con- tained a report on the collections of birds made during the voyage of H.M.S. Challenger at Tongatabu, the Fiji Islands, Api, New Hebrides, and Tahiti. — Mr. Edward R. Alston read a supplementary note on rodents and marsupials from Duke of York Island and New Ireland. Macropus lugens, Alst., was shown to be a synonym of Helmaturus brownii, Ramsay, while Mr. Ramsay's Mus. echimyoides and M. miisavora were respec- tively identical with Miis. brownii and Uroinys rufescens of Alston. — A communication from Mr. L. Taczanowski contained a supplementary list of birds collected in North- Western Peru by Messrs. Jelski and Stolzmann. Two species were new, and proposed to be called Rallus cvpereii and Penelope albipennis. Cambridgk Philosophical Society, October 22. — A communication was read by Mr. Balfour, on the development of the vertebrate ovum. The points dealt with in this paper were (i) the nature of the stroma of the ovary, and (2) the relation of the perma- nent ova to the large cells of the germiral epithelium, named primitive ova by Waldeyer. October 29. — Mr. Bonney read a paper on the rocks of the Lizard District (Cornwall). The author brought forward evi- dence to prove that the serpentine of this district was clearly intrusive among the hornblende schists. November 5. — Prof. Clerk Maxwell communicated to the society an account of the unpublished papers of the Hon. Henry Cavendish, which contain his experiments in electricity. Manchester Literary and Philosophical Society, October 2. — Rev. William Gaskell, M.A., in the chair. — A case of flowering of Chctmerops fortunei ( Hook) at Alderley, by Arthur W. Waters, F.G. S. The fact of C ha i?ierops fortunei {Yiodk) flowering so far north as near Manchester seemed to the author to be of sufficient interest to be worth mentioning to the Society. — Table of effect of movement of the surface of the globe on the shifting of the axis of the earth,by Arthur W. Waters, F.G.S. Paris Academy of Sciences, November 19. — M. Peligot in the chair : — The following papers were read : — Meridian obser- vations of small planets at the Greenwich and Paris Observatories during the third quarter of 1877, communicated by M. Villarceau. — New remarks on the quantities of heat liberated by mixture of water with sulphuric acid, by M. Berthelot. He affirms that sulphuric acid always liberates the same quantities of heat whether it have been recently heated or kept a considerable time. — Resumi of a history of matter (fifth article), by {M, Chevreul. — On the theory and the various manoeuvres of the economising apparatus constructed at the dam of Aubois, by M. de Caligny. — On the use of refined neutral oils for lubrication of pistons in engines with surface con- densers, by M. Allaire. Lime causes decomposition of neutral fatty matters and unites with their acids, the result being a greater deposit than if lime had not been used. Doubt- less the deposit is oleate of lime instead of oleate of iron, and the boiler is preserved from attack ; but the inconveniences in con- densing engines are aggravated, for the condenser ceases to act as the tubes get covered, M. Allaire commends the use of refined neutral fatty matters which are undecomposable under the ordinary pressure of boilers. — Various observations on phyl- loxera, by M. Boiteau. The winter egg is deposited exclusively on the exterior of the stock. — Discovery of a small planet at Ann Arbor, by Mr. Watson. — General map of the proper motions of stars, by M, Flammarion. One result of this com- parison is contradictory of some common views as to the distance of stars relatively to their order of brightness ; for the greatest proper motions do not belong to the most brilliant stars, but indifferently to all sizes. Again, the author cannot support Bessel's and Struve's view that double stars are carried through space more rapidly than simple stars. — On the equation with partial derivatives of the fourth order, expressing that the problem of geodesic lines, considered as a problem of mechanics, supposes an algebraic integral of the fourth degree, by M. Levy. — New applications of a mode of plane represen- tation of classes of ruled surfaces, by M. Mannheim. — On the laws which rule the order (or class) of plane algebraic curves, of which each point (or each tangent) depends at once on a variable point and tangent in a given curve, by M. Fouret. — Extract from a letter (mathematical) to M. Her mite, by M. Fuchs. — On the decomposition into first factors of the numbers 2" ± I, by M. de Longchamps. — Reproduction of orthose, by M. Hautefeuille. Orthose can be obtained by raising to from 900 to 1,000 deg. a mixture of tungstic acid and a very alkaline silico-aluminate of potash containing one equivalent of alumina to six of silica. The tungstic acid forms tungstate of potash, and the silico-aluminate is thus brought to the composition of orthose. — On the composition and industrial use of gases from metallurgical furnaces, by M. Cailletet. These gases, if suddenly cooled, are found to contain an important quantity of combustible principles which can easily be lit again and burnt by passing, e.g., through a grate with burning fuel, and having their velocity diminished. — Forma- tion of iodous acid by the action of ozone on iodine, by M. Ogier, — On the solubility of sugar in water, by M. Courtonne. A saturated solution of sugar at 1 2 "5° contains 66 '5 gr. per cent, of sugar ; one at 45° contains 71 gr. per cent. — On the products of oxidation of camphor, by M. Montgolfier. — Note on the accessory discs of the thin discs in striated muscles, by M. Renaut. Muscular striation is formed of a succession of thick discs alone contractile, and of clear bands traversed each by a thin disc and two accessory discs similar to each other as regards form, and probably having similar functions. — A nalgesia ob- tained by the combined action of morphine and chloroform, by M. Guibert. A subcutaneous injection of chlorhydrate of morphine is made at least fifteen minutes before inhalation of chloroform. — On the causes of violet colour in oysters of the basin of Arcachon, by M. Descoust. The colour is found to be due to the presence of a small algal of the family of Rhodo- spermese and Florideas. This becomes more abundant in time of drought, and probably acts by absorbing moisture. — On the migrations and metamorphoses of the taenia of shrew mice, by M. Villot. — On certain monstrosities of Asterocanthion rubens, by M. Giard. — On the embryogeny of the cestoides, by M. Moniez. — On the bismuth ores of Bolivia, Peru, and Chili, by M. Domeyko. CONTENTS Page Flora of Mauritius anh Seychelles. By W. R. McNac ... 77 Our Book Shklf : — Von Hauer's " Die Geologie " 78 Letters to the Editor : — Fritz Muller on Flowers and Insects. — Charles Darwin, F.R. S. . 78 The Radiometer and its Lessons. — G. Johnstone Stonev ; Prof. G. Carey Foster, F.R.S 75 Mr. Crookes and Eva Fay. — Dr. VVilliaji B. Carpenter, F.R.S. 81 Potential Energy. — Prof. H. W, Lloyd Tanner 81 Smell and Hearing in Moths —George J. Romanes ; J. C. . . . 82 Meteorological Phenomenon. — Joseph John Murphy .... 82 Our Astronomical Column : — Stellar Systems 82 The Minor Planets 83 The Cordoba Observatory 83 Carl von Littrow 83 Bacteria. By J. Burdon-Sanderson, M.D., LL D., F.R.S. . . . Diffusion Figures in Liquids. By Prof. Tito Martini {With lUus- iratioiii) 87 Traces of Early Man in Japan. By Edward S. Morse .... 89 Notes 89 The Liberty of Science in the Modern State, H. By Prof. Rudolf Virchow 92 The Meteor 94 University and Educational Intblugbncb 95 Societies and Academies 95 NA TURE §7 THURSDAY, DECEMBER 6, 1877 TECHNICAL EDUCATION I^ROF. HUXLEY has seized the occasion afiforded him by his promise to aid the Working Man's Club and Institute Union by contributing to their present series of fortnightly lectures, to state his opinion on a question which, as we have already informed our readers, has lately been exercising the minds of some of the most influential members of various city companies. For some time past a joint committee, representing the most important among these bodies, has been endeavour- ing to obtain information as to the best means of applying certain of their surplus funds to the assistance of what is called technical education, and there is little doubt that a proposal for a huge technical university, made some time ago, and the discussion which took place in connection with that proposal, has had somewhat to do in leading to the present condition of affairs. Prof. Huxley and some four or five other gentlemen have been appealed to by this joint committee to send in reports on what they consider the best way to set about the work, and it is from this point of view that Prof. Huxley'* lecture is so important. It was not merely fresh and brilliant and full of good things, as all his lectures are, but is doubtless an embodiment of his report to the joint committee. We are rejoiced, therefore, to see that Prof. Huxley is at one with the views which we have all along expressed in Nature, namely, that, after all, the mind is the most important instrument which the handicraftsman, whether he be a tinker or a physiuist, will ever be called upon to use, and that therefore a technical education which teaches him to use a lathe, or a tool, or a loom, before he has learned how to use his mind, is no education at all. Prof. Huxley not only defined technical education as the best training to qualify the pupil for learning techni- calities for himself, but he stated what he considered such an education might be, and how the city funds can be best spent in helping it on. Besides being able to read, write, and cipher, the student should have had such training as should have awakened his understanding and given him a real in- terest in his pursuit. The next requirement referred to was some acquaintance with the elements of physical science — a knowledge rudimentary, it might be, but good and sound, so far as it went, of the properties and cha- racter of natural objects. The professor is also of opinion that it is eminently desirable that he should be able, more or less, to draw. The faculty of drawing, in the highest artistic sense, was, it was conceded, like the gift of poetry, inborn and not acquired ; but as everybody almost could write in some fashion or other, so, for the present purpose, as writing was but a kind of drawing, everybody could more or less be supposed to draw. A further desideratum was some ability to read one or two languages besides the student's own, that he might know what neighbouring nations, and those with which we were most mixed up, were doing, and have access to valuable sources of infor- mation which would otherwise be sealed to him. But above all- and this the speaker thought wai th« moit Vol. xvii, — No. 433 essential condition— the pupil should have kept in all its bloom the freshness and youthfulness of his mind, all the vigour and elasticity proper to that age. Pro^. Huxley then went on to explain that this freshness and vigour should not have been washed out of the student by the incessant labour and intellectual debauchery often in- volved in grinding for examinations. We gather from this part of the address— we shall refer to the others by and by— that so far as Prof. Huxley's advice goes we are not likely to see any great expenditure of the money of the ancient city corporations either in the erection of a huge "practical" university or in the creation of still another " Examining Board." How then does he propose to spend it ? Here we come to a substantial proposal, which Prof. Huxley may consider to be the most important part of his address. What is wanted, he considers, is some ma- chinery for utilising in the public interest special talent and genius brought to light in our schools. " If any Government could find a Watt, a Davy, or a Faraday in the market, the bargain would be dirt cheap at 100,000/." Referring to his saying when he was a member of the London School Board that he should like to see a ladder by which a child could climb from the gutter to the highest position in the State, he dwelt upon the importance of some system by which any boy of special aptitude should be encouraged to prolong his studies, to join art and science classes, and be apprenticed, with a premium if necessary. In the case of those who showed great fitness for intellectual pursuits they might be trained as pupil- teachers, brought to London, and placed in some col- legiate institution or training school. In this way the money of the guilds would be spent in aiding existing teaching systems, in which, on the whole, an enormous progress was acknowledged. It is true the architects of London would not have the opportunity of immortalising themselves by erecting an imposing edifice, but, on the other hand, the influence of the Guilds might be felt whenever there was a handicraft to foster, or a potential Watt to be sought out. We do not imagine that it is Prof. Huxley's idea that there shall be no local representation of the city's new activity and influence ; the reference to the training of teachers, we fancy, and other remarks here and there, seem to point to some such institution as the jfecole Normale of Paris, where the best and most practical scientific teaching could be carried on. Every one knows how much room there is for such an institution as this, but on this little money need be spent, '"so far as bricks and mortar are concerned, as little money is needed to equip such laboratories as are really meant for work. There is an advantage in such lectures as these by no means limited to the expression of opinion on the part of the speaker. The slow and sure way in which science is taking a hold upon our national progress is well evidenced by the fact that the daily press can now no longer ignore such outcomes as these, and hence it is that they do good beyond the mere boundary of the question under discussion. They show the importance of, and foster interest in, the general question of intellectual and scien- tific progress. The Timts agrees in the main with the kind of educa- 98 NATURE {Dec. 6, 1877 tion to be given, and holds that " What is needed is to give a man the intelligence, the knowledge of general principles, combined with the habits of correct observation and quick perception, which will enable him afterwards to master the technicalities of his art, instead of becoming a slave to them. No objection can be taken to the advice that, for this purpose, a lad, after learning to read, write, and cipher, should acquire some facility in drawing, and should be familiarised with the elements of physical science. The importance of the latter study for this particular purpose is, indeed, unquestionable, and even paramount, for a handicraftsman is dealing exclusively with physical objects in his work, and his skill in applying the processes of his craft will vary in great measure with his knowledge of the scientific principles on which they depend." But we fancy that the Times writer does not look upon this scientific part of education quite as the lecturer does, for he proceeds to add : "There can be little doubt, for instance, that many of the perils of mining might be averted if the miners were alive to the scientific reasons of the precautions they are urged to adopt. Many an improvement, probably, which now escapes the eye of a man who adheres slavishly to the rules of his craft would occur to him if he were applying them with conscious intelligence." The Times, however, considers that the school-time is too short for the languages, and curiously enough drives its point home by saying a harder thing about the Greek and Latin of our public schools than Prof. Huxley has ever done ; while, on the other hand, the Daily News points out that Prof. Huxley this time may have raised a hornet's nest about his ears by the unduly reasonable tone of his demands. The Daily Neivs then adds : — " A man of science who does not demand that from the earliest age an hour a day shall be devoted to each of the ologies may be regarded as a traitor to his cause." For our part we know of no man of science who has ever made such a demand ; and a careful examination of what men of science have said on this point for the last ten years will show that these extreme views to which reference is here made are not those of men of science at all. It will be well also if the strong language used in connection with the multiple examinations of the present day brings that question well before the bar of public opinion. The Times is " sorry to see another flout thus inflicted, in passing, on that system of examinations which, like most good institutions, may do harm to the few, but is indispensable as a motive for work to the great majority." Prof. Huxley has expressed the views of most of the leading teachers in this country with regard to the effect of these examinations upon the students, and he might have referred to their reflex action on the examiner. Go into a company of scientific men, and observe the most dogmatic, the most unfruitful, and the least modest among them, you will find that this man is, as we may say, an examiner by profession. Speak to him of research or other kindred topics, he will smile at you — his time is far too precious to be wasted in discussing such trivialities ; like his examinees, he finds they do not pay. The example set by Germany in this respect, both as regards students and professors, cannot be too often referred to, and there is •IT • little doubt that the love of science for its own sake which has made Germany what she now is intellectually, has sprung to a large extent from the fact that each young student sees those around him spurred from within and not from without. Noblesse oblige. In point of fact so far as our future scientific progress is concerned the examination question is as important as that connected with the kind of education to be subsidised by the city guilds, and it is important, seeing that our legislators will, in the coming time, have to give their opinion on these subjects as well as on beer, vivisection, and contagious diseases, that in Prof. Huxley's language "by the process called distillatioperasceiisum — distillation upwards — there should in time be no member of Parliament who does not know as much of science as a scholar in one of our elementary schools." NORTH AMERICAN STARFISHES Memoirs of the Museum of Comparative Zoology at Harvard College. Vol. v. No. i. North American Starfishes. By Alexander Agassiz. With Twenty Plates. (Cambridge, U.S., 1877.) '"T^HIS memoir consists of two parts. The first con- J- tains a history of the Embryology of the Starfish, which is substantially the same as that pubhshed in 1864 as Part I., Vol. v., of Prof. Agassiz's " Natural History of the United States." The author has, however, added notes on the points where additions have been made by subse- quent investigations. The second part treats of the solid parts of some North American starfishes. The plates accompanying the second part were intended to form part of one of Prof. L. Agassiz's volumes of " Con- tributions to the Natural History of the United States," and have been drawn for more than twelve years. The late Prof. Agassiz intended to add them as illustrating the anatomy of several of the more common American species. Under these circumstances the memoir is wanting in the completeness that distinguishes some of the other Memoirs of this series, such as that " On the Ophiuridae," by Lyman, and that " On the Echini," by Alexander Agassiz ; but though the subject of the Starfishes as thus presented is incomplete, it is beyond a doubt that we have here a work of great value that will serve not only as illustrating a number of American species, and showing the systematic value of characters often almost com- pletely overlooked, but as determining the homology of several genera not previously figured, and of which the details of the solid parts are fully given. The arrangement of the star-fishes into families adopted does not materially differ from that given by Perrier in his revision of the group. No general list, much less a synonymic catalogue, as in the case of Echini, is given ; and this because the number of species in the hands of Prof. Perrier, from the Florida dredgings, as well as those found by the Challenger expedition, have added a number of remarkable forms not yet wholly determined to the American starfish fauna. ,-3: '.-: iu: «'•: •-re -. . The author reminds us that the transformations pleculiar to the Echinoderms constitute neither a metamorphosis nor a case of alternate generation. The egg becomes the embryo laxva. Nothing essential is lost during the Dec. 6, 1877] NATURE 99 process. No intermediate form comes into the cycle ; the yolk becomes the larva, and this latter becomes the young Echinoderm ; and this larva is, according to A. Agassiz, an Acalephian larva, reminding one somewhat of the twin individuals of free Hydroids as Diphyes, though adapted to the mode of development of the Echinoderms. The Echinoderm; plutean form, with its mouth-stomach intestine, and with its water system originally forming a part of the digestive cavity, bearing as it would seem, about the same relation to the Ctenophoras, which the Ilydroid Polyps hold to the true Polyps. Therefore Agassiz cannot admit that the views so frequently urged and so generally admitted as to the separation of the Acalephs and Polyps as a distinct type (Coelenterata) from the Echinoderms have any foundation in nature. He would therefore still retain the Radiate sub-kingdom with its three equivalent classes — Echinoderms, Acalephs, and Polyps. Agassiz thinks G. O. Sars' idea that Brisinga is the living representative of the paleozoic starfishes rather too far-fetched, and he sees no very radical difference between Brisinga and such ordinary starfishes as Solaster and Crossaster, and he considers that if there has been a single ancestral Echinoderm, his primordial descend- ants early assumed different lines of development diverg- ing to a great degree, and retaining their characteristics from the earliest-known geological period, E. P. W. VOCE US ''SPECTRUM ANALYSIS" Practische Spectralanalyse irdischer Stoffe. Von Dr. Hermann W. Vogel (Nordlingen : C. H. Beck.) '"r*HE aim of the author in writing this book may best -*- be described in his own words. He says in the introduction : — " The many^ excellent popular books on spectrum analysis confine themselves chiefly to descriptions of the great discoveries made by means of it ; the chemical books only give short descriptions of flame reactions of alkalies and alkaline earths'; they contain seldom a detailed account of the methods of observation, and still less a description of absorption spectra. The present work is intended to fill up this want, and to be a text-book to the student, and a reference book to the initiated." Prof. Vogel is an authority on the absorption spectra of liquids and solids. Nearly half the book is given up to them, and we must add the better half. Here we find for the first time a connected account of all that has been done on the subject. Such an account is exceedingly valuable, and it brings prominently forward the gaps which have yet to be filled up. Prof. Vogel treats the subject chiefly from the chemical point of view, but those who take greater interest in the theoretical part will also find excellent information. So, for instance, the effect of the solvent on the absorption spectra of solutions is dis- cussed. The spectra of colouring matters are given in detail, and the account of the effect of chemical reagents on them will be found exceedingly interesting. There is no doubt that this part of the book will be of great use to every worker on the subject. We wish we could say as much of the chapter on emission spectra. As long as the author treats of the spectra of alkalies and alkaline earths, he is on safe ground, but when he comes to discuss the question of double spectra and the spectra of gases, he is confused and unintelligible. Led away apparently by a desire to do justice to every writer, he quotes approvingly the most divergent opinions, as if they could be consistently held at the same time. He is very fond of saying that a body has been proved to have two spectra but that one of them belongs to the oxide or to an impurity, which is the same as saying that he possesses two watches but that one of them belongs to his brother. The author is throughout the book careless in his expressipns, and this comes prominently forward in this chapter. What, for instance, can the student make of the following paragraph (p. 170)?— " A stro)ig electric spark passing throus;h air gives the sped nun of oxygen together tuith that of nitrogen. Both together form the so-called spectrum of air. Only one spectrum of oxygen is known. In dry pure air the spark only generates the spectrum of nitrogetiJ' The two statements in italics contradict each other as they stand. One of them is true for higher pressures, the other for lower pressures, but this the author has forgotten to add. It must be said that the subject is a complicated one, and even those who are practically acquainted with all the experimental details would find it difficult to give a connected and clear account of it. The first part of the book which treats of the optical principles involved in the spectroscope is apparently well written, and the student will find in it elementary proofs of some important theorems. '^ Arthur Schuster OUR BOOK SHELF Nyassa ; a Journal of Adventures whilst Exploring Lake Nyassa, Central Africa, and Establishing the Settlement of '' Livingstonia^ By E. D. Young, R.N. Revised by Rev. Horace Waller. With Maps. (London : John Murray, 1877.) This is a thoroughly interesting narrative, brisk, fresh, and instructive. Mr. Young tells the story of the planting of a missionary station under the united auspices of the Presbyterian churches of Scotland, at Cape Maclear, on the south-west corner of Lake Nyassa. Mr. Young for the most part takes us over classic ground, by the Zambesi and Shird, over ground familiar to readers of Livingstone's earlier and his latest travels. Mr. Young in his hardy little steamer the I lata, surveyed the north end of Lake Nyassa for the first time, discovering on its north-east shore a magnificent range of mountains, rising to from 8,000 to 12,000 feet above the level of the lake, and which he named after his old friend Livingstone. On the opposite shore is a range of less elevation. The lake is marshy at the north end, subject to quite oceanic storms, its shores being marked by varied and most attractive scenery. The steamer caused tremendous consternation among the slave-trading Arabs, who seemed to feel that with the advent of a British steamer on the lake their occupation was gone. The settlement was successfully planted and is likely to be of service both as a centre of civilisation and of more minute exploration. Britannia : A Collection of the Principal Passas;es in Latin Authors that Refer to this Island. With Vocabu- lary and Notes. By Thos. S. Cayzer, Head-Master of Queen Elizabeth's Hospital, Bristol. Illustrated with a'Map and twenty-nine Woodcuts. (London : Griffith and Farran, 1878.) The title-page sufficiently describes the contents of this I As a personal question I may add that fhe remark attributed to me on page 198 was made by Mr. Stoney and only quoted by me. — A. S. ICO NA TURE [Dec. 6, 1877 little volume. We think the idea of making such a col- lection a happy one, not only for scholastic purposes, but also for the use of those who wish to be able at any time easily to refer to any of the passages in Latin authors in which our island is referred to. Mr. Cayzer gives also translations of some of the chief references in Greek writers. We should think, if teachers and examiners could be persuaded to break through custom, the intro- duction of such a book into schools would add interest to the reading of Latin, and furnish, besides, the little fellows with a stock of valuable information. Most of the cuts are appropriate, several being old friends. LETTERS TO THE EDITOR \Tht Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undei-take to return^ or to correspond with the writers of, rejected manuscripts. No notice is taken of anonymous communuations. TTie Editor urgently requests correspondents to hap their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of com- munications containing interesting and novel facts.\ The Colour-Sense of the Greeks Mr. Gladstone has shown that the language of Homer is an inadequate vehicle for conveying precise and nicely distinguished ideas of colour. Whether the nation that was content to describe colours so imperfectly was also incapable of subtle perception of tones of colour is clearly another question. Language does not keep pace with perception unless a practical or resthetic necessity arises for expressing what is perceived in words to other people. Practical necessity gives names to pigments and bright objects, such as flowers and precious stones, rather than to tones of colour ; the aesthetic necessity that lies upon the artist to utter what he has felt will naturally lead to imitative expression sooner than to an expression that is merely symbolical. In other words an early race will learn to use colour with nicety for decorative and pictorial purposes before it develops the distinctions of language requisite for accurate word-painting. That this was actually the case among the Greeks appears, I think, very clearly in a passage of Ion which is preserved to us in Athenseus Deipnos., Lib. xiii. cap. 81 (p. 603 seq.). Ion, who was a contemporary of Sophocles, describes an evening which he spent with the great tragedian in Chios. Sophocles, admiring the blushing face of a little boy who served the wine, quoted, with high approval, a line of Phrynicus : — " The light of love gleams on the purplecheek." On this a certain pedantic grammarian breaks in — "In sooth, Sophocles, thou art skilled in poetry ; but yet Phrynicus spoke not well when he called the cheeks of a beautiful person purple. For if a portrait-painter were to colour the cheeks of this boy with purple pigment he would no longer appear beautiful. It is not fitting to compare what is beautiful with what is not so." Sophocles laughs at the objection, and replies — " Neither, then, my fiiend, wilt thou be pleased with that line of Simonides which, to the Greeks, has appeared very well said : — * The maiden sending forth her voice from her purple mouth ; ' nor with the poet, when he says, ' golden-haired Apollo ; ' for if the painter made the hair of the god golden and not black, his picture would be less excellent. Nor wilt thou be pleased with him [Homer] who said * rosy-fingered,' for if one were to dip the fingers in rose-colour, one would produce the hands, not of a fair woman, but of a dyer of purple." This retort produced a general laugh, and confounded the pedant not a little. The Greeks, then, were perfectly aware of the insufficiency of the poetic vocabulary of colour ; and accordingly they did not expect descriptive rendering of colour from the poet. This, it is plain, is a circumstance that must constantly be kept in view in any attempt to find in the poetry of the Greeks a measure of the development of their colour-sense. Aberdeen, December 3 W. Robertson Smith The Comparative Richness of Faunas and Floras Tested Numerically In his letter in Nature, vol. xvii. p. 9, Prof. Newton has strongly brought out the abstudity of comparing districts of very different areas by the proportionate number of species to area in each. On this principle he shows that to be equally rich with the small island of Rodriguez, Madagascar ought to possess four times as many species of birds as exist throughout the whole world ! It does not, however, by any means follow that the method thus expo-ed may not be of value in comparing regions of approxi- mately equal area, as is the case with several of the primary regions, to determine the comparative richness of which Mr. Sclater first applied it. I have not Mr. Sclater's paper at hand, but it is my impression that he made no attempt to sho w— " that the proper mode of comparing the wealth or poverty of one fauna with another was to state the proportion which the number of species composing it bears to the area over which they range " — as Prof. Newton implies that he did, but that he merely adopted this method as the only one readily available for the comparison of his regions. Although I took the opportunity of making some corrections in the figures, I never committed myself to the principle ; and I very soon afterwards found that it was not to be trusted. As, however, several later writers have made use of it without remark, it will be interesting to consider where the exact point of the fallacy lies, and with what modifications the method can be trusted to give useful and consistent results. If we compare two islands of almost exactly equal areas, such as Ceylon and Tasmania, and find that the one has twice or three times as many species of mammals or birds as the other, it will be generally admitted that we express the fact correctly when we say that, as regards such a group of animals, the one is twice or thrice as rich as the other ; and the same may be said of two countries or two continents of identical areas. For on the supposition that there is a general correspondence between the numbers of rare and common, of local and of wide-spread species in the two areas compared (and this seems probable), then the average number of distinct species to be m^t with on one spot, or to be seen during a journey of equal length, will be proportionate to the total number of species in the two areas. But now let us divide one of the two continents or islands which we are comparing into two or more parts. We know, as a matter of fact, that one-half the area will always contain much more than half the total number of species, while one-tenth of the area will contain immensely more than one- tenth of the species. To take an example : the county of Sussex is about one-eightieth part the area of the British Isles, yet it ac- tually contains full two-thirds of the total number of flowerino' plants, both being estimated by the same flora (Babington's. "Manual," fifth edition, British Isles 1,536 species, Sussex 1,059 species). If we now compare either Britain or Sussex with an eqtial area on the continent of Europe or North America, we may obtain an instructive estimate of the comparative richness of their respective floras ; but if we compare unequal areas, and then endeavour to equalise them by getting the proportions of species to area, we shall obtain erroneous results, which will become literally absurd when the areas compared are very unequal. The problem remains, how to compare unequal areas of which we possess the zoological or botanical statistics. We can only do so by equalising them, and this may not be so difficult as at first sight appears. For example, let us take the Palsearctic and North American regions, in which the species of birds are nearly equal in number, but the areas are as about seven to three. The number of the Palasarctic species have, however, been propor- tionately increased of late years, and if we take the western half of the Palaearctic region so as to include North Africa and Persia we shall have an area about equal to the Nearctic region, and a number of species perhaps one-sixth or one-eighth les>, which will thus represent the comparative richness ol these two areas. The eastern half of the region, including Japan and North China, is probably as rich as the western ; while the iijtc:rmediate portion is poorer in species. Combining these three portions, and taking the average, we should perhaps find the Palasarctic region about four-fifths or five-sixths as ricti as the Nearctic, instead of less thaa one-half, as shown by the method of proportionate areas. Whenever we know how xaz.riy peculiar species any district contains, we can deduct its area from the total area of the region to be compared, and this numbtr of peculiar species, from the fauna of the region ; and by this means we may reduce two unequal regions to comparative equality. Again, all detached portions or inlands should be omitted in estimating the compara- tive richness of regions, because they affect these regions very unequally. By adding Britam to Europe you increase the area without adding to the fauna, and thus make the region seem poorer ; while by adding Madagascar to Africa, or New Zealand Dec. 6, 1877] NATURE lOl to Australia, you "add to the fauna in a greater proportion than you increase the area, and thus make the region seem richer. For a fair comparison continents should be compared with continents, and islands with islands, and these should in every case be brought to an approximate equality of area by lopping off outlying portions with their peculiar species. We shall then get results which will be instructive, and which will afford us a true estimate of the comparative richness of different countries in tlie several classes of animals and plants, Alfred R. Wallace Mr. Crookes and Eva Fay I.\" Dr, Carpenter's eagerness to show that his statements about Mr. Crookes and Eva Fay had some bisis of fact, he seems entirely to have forgotten the real issue which he has himself raised, and which is of great importance to all engaged in the study of these tabooed subjects. The question simply is, whether any investigation of the alleged abnormal powers of individual?, however painstaking and complete it may bp, and however decisive its results, is to be branded with opprobrious epithets, without any proof of error or fallacy, but merely on the dicta of newspaper writers and alleged " exposers," In the case before us Mr, Crookes made certain experiments in his own laboratory, in which the greatest refinements of modern electrical science were employed ; and of these he pub- lished a detailed account. That is the sum total of his acts and deeds in regard to Eva Fay. Yet because these experiments have been referred to in America as indorsing Eva Fay's remark- able powers, and because some persons charge her with being an impostor, and go through an alleged imitation of her perform- ances, Dr, Carpenter accuses Mr, Crookes of encouraging "dis- gracefulfrauds " and indorsing a "notorious impostor," Now it is clear that, to support this accusation, Dr, Carpenter must • that Eva Fay was an impostor in respect to what happened 'Jr. Crookes's house, and that, to use Dr, Carpenter's own .. .ais, she evaded his "scientific tests" by a " simple dodge," He must prove that Mr, Crookes exhibited culpable careless- ness or incapacity in accepting, as conclusive, tests which were really fallacious ; for, otherwise, how can Mr, Crookes be held responsible for anything which happened afterwards in America ? Dr, Carpenter has promised to do this in the forthcoming new , edition of his lectures ; but as the accusation against Mr, Crookes , has been made in the pages of Nature, and the question is a ; purely scientific one — that of the absolute completeness of the ^ test of "electrical resistance"— I call upon Dr, Carpenter to [explain fully to the readers of Nature the exact particulars of that "simole dodge " which is to destroy Mr, Crookes's reputa- tion as a physical experimenter, and to sustain the reputation of 'lis accuser. Unless the explanation is so clear and conclusive s to satisfy all the witnesses of the experiments that Eva Fay Hid evade the scientific tests, and that what they saw was simple onjurin?, then Dr. Carpenter is bound to find a conjuror who ivill submit to the same tests as Eva Fay did, and produce the >ame phenomena before the eyes of the witnesses, so as to show 'how it is done," Mr, Maskel)me, who professes to have ixposed Eva Fay, will of course be ready to do this lor an ade- }uate remuneration, which I feel sure will be forthcoming if Dr, Carpenter is proved to be right and Eva Fay's " simple dodge " js clearly explained, I have already shown (in this month's Fraser) that the sup- posed exposure of Eva Fay in America was no exposure at all, 3Ut a clumsy imitation, as will be manifest when it is stated that he exposer, Mr. Bishop, performed all his tricks by stretching 'he cord with which his hands were secured to the iron ring behind his back ! There is hardly a greater exhibition of ;redulity on record than Dr. Carpenter's believing that such a 'performer proved Eva Fay to be an impostor and Mr. Crookes's bcperiments valueless. But what can we expect when we find a VaUy Telegraph report quoted as an authority ^in a matter of itcientific inquiry ? I venture to think that, whatever may be their opinions as to he amount oi/act in the phenomena called "spiritualistic " (by )r. Carpenter, but never by Mr. Crookes), all men of science nil agree with me that Dr, Carpenter is bound to prove by 'Urect experiment \\\-3ii Mr. Crookes and his coadjutors were the ■ictims of imposture on the particular occasion referred to ; or if ae fails to do this, that he should in common fairness publicly withdraw the injurious accusations he has made against Mr, !^rookes and all who are engaged in similar investigations. If his is not done it is equivalent to deciding that no possible proof of such phenomena is admissible — a position which is not that ot Dr. Carpenter, or, as far as I am aware, of the scientific world generally, I beg to take this opportunity of apologising for my involun< tary appearance under false colours in this month's Fraser. The letters "F.R.S. " were added to my name after the corrected proofs left my hands and wholly without my knowledge. I have desired the editor to make a statement to this effect in his next issue, but in the meantime wish to set myself right with the readers of Nature. Alfred R. Wallace Nocturnal Increase of Temperature with Elevation With reference to the article in Nature, vol. xvi, p. 450, on the above subject, allow me to place on record the following facts. On the night of January 7, 1874, in Lucknow, the tem- perature fell considerably below the usual. The minimum thermometer on the grass at the observatory registered 5° below freezing point. The destruction of plants in the Horticultural Gardens was great. Plantains, pine apples, sugar-cane, mango trees, casuarinas, pomsettias, colvilleas, bugainvilleas, &c., &c,, were all injured ; some killed outright. The remarkable fact which I observed on that occasion was, that the destruction of vegetation was only up to a certain height, viz., up to between seven and eight feet from the ground. Above that, not a leaf was touched by the frost. On the mango trees especially, which were planted close to each other, it was very remarkable to see a distinct line of destruction along the trees, of seven or eight feet from the ground. This, I think, distinctly showed that the temperature on that night, above eight feet from the ground, was decidedly warmer, and thus protected all vegetation, while all below it was more or less injured, or killed by frost. Other observations, I made lately, corroborate the result of the direct observations made by Mr. Glaisher. During the commencement of October there were several rainy days, with an easterly wind ; the total rainfall was under 2^ inches. When it ceased, and the clouds cleared away, I observed the following : — Before seven o'clock in the morning there were only a few low-lying clouds to be seen. As the sun rose, the wind still in the east and almost a calm, clouds began to form in all directions; about noon, and till about 3 P.M., the sky was thickly studded with cumuli of "various sizes. After that hour, wider and wider gaps began to form between the clouds, and the dissolving cf the cloud-masses continued as the sun approached setting. About two hours after sunset there was scarcely a cloud to be seen, and the twinkling stars came out in their full brilliancy. This melting of the clouds after a certain hour, and completely so after sunset, would, I think, indicate that the cloud region after sunset became decidedly warmer than it had been^during the day. E. BONAVIA Lucknow, October 22 Expected High Tides Mr, Edward Roberts in his letter has, I think, missed the chief object I had in addressing you, I did not complain that the authorities had not taken pains to calculate the heights of the tides, but that while one could take up almost any paper on the coast and find the heights of the tides of the place for the coming week, not one of the London papers, so far as I could find, supplied this information for its readers. What I felt to be a desirable thing was that the Meteorological Office, or some other constituted authority, should send to the daily papers warnings, when necessary, that on such a day a dangerous tide might be expected with a wind from such a quarter and with such a barometer, as the tide would be unusually high under even favour- able w^eather — in fact, give a forecast of the tide. It is almost useless to ask the public or vestries to put two or three facts together and think out the matter for themselves ; they require some authoritative announcement to prepare for danger. And this is the more necessary as an overflow of the Thames at above-average spring tides is, as Mr, Roberts says, now a matter of meteorological circumstances only, and on account of the increased range of the tide in the river, I was not aware that Captain Saxby had predicted high tides so far back as 1869, If, as Mr, Roberts says, the Astronomer- Royal wrote re-assuring the public that there was nothing extraordinary in the November 3 tide, and as, on the contrary, that tide rose 3 feet 3 inches above Trinity high- water mark, this incident may possibly have had something to do with the establishing of Captain Saxby's reputation with the public as a predictor of tides, I02 NATURE {pec. 6, 1877 especially if he had previously predicted the great tide of March i of the same year, which rose to 3 feet 7 inches above the mark. With respect to the actions of the planets, I did not refer to the ordinary tide-producing power, for on working that out some years ago for one of the planets I was somewhat surprised to find that the height was, I believe, a fraction of an inch, I referred rather to the action of that storm-producing power which appa- rently gives rise to the great atmospheric disturbances at certain times (and, indeed, more or less at all times) in the sun, and by sympathy, or even directly, in our atmosphere. B. G. Jenkins Diffusion Figures in Liquids Prof. Martini describes his diffasion figures as being "both new and singular." In the Phil. Mag. for June and November, 1864, I have described and figured various examples of what I call " the submersion figures of liquids " in continuation of a series of papers commenced in 1861 on " The Cohesion Figures of Liquids," or those assumed by liquid drops when delivered to various surfaces. Some of these figures are identical with those given by Mr. Worthington in the Proceedings oi the Royal Society for 1876, and recently in your pages. C. Tomlinson Highgate, N., December 3 Bees and Flowers In last Thursday's impression (p. 62) is a letter from Mr. H. O. Forbes, referring to bees confining their visits to plants of one kind during each excursion, and thus in a measure prevent- ing hybridisation of plants, &c. This may be the general habit of bees, but it is not invariable ; some bees, more especially their females, are to be found at certain plants only, as Andrena hattorfiana, at the scabious Colletes succincta, at the heath, and many others in like manner. I have collected bees for several years, and have often taken them with the pollen-grains varying from orange-red to almost white, and this mixtui-e on the same leg. I have inclosed a slide of pollen-grains which I washed from the leg of an Andrena nigro-anea, and mounted in balsam ; this shows several very distinct kinds of pollen ; this was mounted in 1875, ^^^^ ^t the time I gathered such of the wild flowers as were then in bloom, and compared the pollen. I was able to identify several of them, but as I made no notes I cannot say which. I would advise such observers as intend investigating this very interesting subject, to capture the insects and examine the pollen which may be found on them ; this will be difficult in the case of the Bombi and Apis, as they knead it into pellets, but with those which collect on the belly or whole leg it will be easy enough. Norwich John B. Bridgman Hearing in Insects My daughter bred this summer a number of the larvse of Sphinx ligustri and Metopsilus elepcnor, and I was much struck with the extreme sensitiveness to the sound of the voice — especially of the former. The child's treble 1 observed did not affect them so sharply ; but at the first word I uttered they invariably started, and remained some time motionless, with head drawn back, after their manner, I was disposed to attribute it to the vibration set up in objects around by sounds toward the deeper end of the scale, as I have felt a form tremble under me at the deep bass notes of a strong singer ; but it had all the appearance and effects of hearing. Henry Cecil IJregner, Bournemouth, December i AZOOLOGICALSTATION FOR THE CHANNEL ISLANDS C OME'definite prospect at length presents itself of the ♦^ establishment within British waters of an institution long recognised as a leading desideratum among our Biologists, Museum-Conservators, and Natural History Students, namely, a building with the necessary appur- tenances suitably situated, and founded on a somewhat similar basis to that of Dr. Anton Dohrn's noted Zoological Station at Naples, or the Anderson School of Natural History at Penikese Island, Buzzard's Bay, U.S. This long-felt need will be met by the proposed " Channel Islands' Zoological Station and Museum, and Institute of Pisciculture " described at some length in the advertising columns of this journal, and the establishment of which, or a similar institution, has been the guiding star and main object of the writer's ambition during the several years' " apprenticeship " spent by him as Naturalist and Curator to the various leading public aquaria of England, Successfully carried out, the more prominent features of this undertaking will comprise, as at Naples, in addition to an attractive public exhibition of the living inhabitants of the surrounding waters, laboratories fitted with tanks, tables, and^all the necessary instruments and apparatus requisite for the satisfactory prosecution of marine biological research, supplemented by a library replete with the standard scientific works and serials mostly in demand by those occupied in such investigation. Under the same roof it is likewise intended to establish a natural history museum accessible to the public, and more essen- tially illustrative of the notably rich marine fauna and flora of the Channel Islands. In connection with the library and museum departments popular lectures upon natural his! ory subjects will from time to time be given. Following the system productive of such gratifying results at the Penikese Island Station, it is further proposed foi the full development of the scientific advantages of this institution to institute summer classes for the attend- ance of students, and to hold out sufficient inducements for the most eminent authorities on various biological subjects to deliver lectures and a course of instruction to these classes upon that branch of natural history with which their reputation is more especially associated. An entirely novel feature to be incorporated with the Channel Islands' Zoological Station will be a department relegated to the conduct of experiments associated with the — in this country— little developed science of economic pisciculture, and in which department it is proposed to award a prominent place to the artificial rearing of lobsters. Experiments made in this direction by the writer some years since at the Manchester Aquarium have decisively shown that the artificial culture of these Crustacea on an extended and systematic scale might be developed into a highly iniportant and remunerative industry. In the experiments here referred to it was found that the little lobsters occupied from six to eight weeks in passing through those singular free swimming larval conditions, known respectively as the "Zoea" and " Megalops " stages, antecedent to their assumption of the adult and ambulatory form, and during which short interval they exuviated or cast their shells many times. These initial metamorphoses safely past, their further development to a marketable size, is a comparatively easy task. The scientific culture of the oyster and other edible species will likewise receive attention in association with this undertaking. The appropriateness of Jersey as a site for this intended Museum of Pisciculture and Zoological Station is at once apparent, the variety and exuberance of the marine fauna of the Channel Islands being such as to assimilate it more closely to that of the Mediterranean than any other one within British waters. The occur- rence on the Channel Islands' coast of the Sea Horse {Hippocampus), Urchin-fish {Diodon), Remora {Echencis)., Electric Ray {Torpedo), and Lancelet {Amphioxiis), among the vertebrate group ; and of the Haliotis, Scylla- rus, Cojnattda, Physalia, Velella, Lncernaria, and many others among the invertebrate section, are a few from among many that might be named in demonstration of this fact. The sponge-tribe and the division of the tuni- cate might be likewise specially singled out. as attaining upon the shores of these islands a development in both numbers and variety rarely if anywhere else excelled. Unprecedented facilities for the collection of all such ma- rine productions are also afforded by the extraordinary Dec, 6. 1877] NA TURE 103 low limit to which the water recedes during the monthly spring-tides. In no case less than thirty, and not unfre- quenily mo-e than forty feet represents the vertical height of the rise and fall of the tide on these occasions, the waves on [their retreat exposing to view and rendering accessible an extent of rocks and life-teeming pools that constitute a veritable elysium to the marine zoologist or botanist. The situation of Jersey, again, is such as to render it not only readily accessible to English naturalists and students, accompanied with just that amount of sea- passage requisite to satisfy the marine predilections of our countrymen, but it is also most conveniently reached from France, Belgium, Holland, and other Northern European countries, and which will thus invest the institution with international utility. Paris, indeed, already supplies a considerable number of the numerous summer visitors to the island, and from these no doubt might be enticed a strong contingent of students for the laboratories. As will be found in the advertisement already referred to, a special appeal is addressed to the scientific section of the community rather than to the general public for the funds required for the successful establish- ment of this institution, and it is certainly most desirable that an enterprise calculated hereafter to confer so great advantages upon this more limited class should receive a fair quota of support through its ranks. The sum total required, in fact — 5,000/. — for the founding of this zoo- logical station, and all accessory departments, is so comparatively small as to place it not quite beyond the pa'e of hope that sufficient enthusiasm to effect the purpose may be yet forthcoming from among the more wealthy devotees to the shrine of science, and in emulation of the praiseworthy example set on the other side of the Atlantic by Mr. John Anderson, the munificent founder and endower of the Pemkese Island Station. At all events, it is scarcely to be anticipated that so desirable an undertaking, replete with such promise of future advantage to the scientific world, will long lack the essential " sinews of war," considering that a contribution by each member of one only of our leading metropolitan scientific societies of less than one-half of his annual sub- scription to that society, would more than suffice to de- fray the whole expenditure contemplated. Through the kind liberality of a few, moreover, and the financial confidence of others, a small but substantial nucleus has been already formed, and it is confidently hoped that the full sum needed may yet be raised in time for naturalists and the public generally to participate in the advantages the Channel Islands' Zoological Station and Museum of Pisciculture will place at their disposal, so early as the summer of the year 1878. In conclusion it is perhaps desirable to note that in drawing up the legal foundation of this Channel Islands' institution the strictest care has been taken to permanently exclude all possible chance of the society's premises being used for any of those attractions of an entirely irrelevant and unscientific nature more usually associated with exhibi- tions of the living inhabitants of the ocean, and the existence of which must ever constitute an insuperable barrier to that good service to science which these last- named establishments might otherwise contribute. It is only under such restrictions as are above set forth that patronage and support are solicited. In recognition of the purely scientific status of this enterprise, the members of the Executive Committee, or Directors of the Society, have also unanimously resolved to accord their services as such members gratuitously ; and it is further j pro posed, so as to divest the undertaking of any merely speculative aspect, that all profits arising from the busi- ness of the hociety, beyond what would yield to the shareholders a return of five per cent, shall be devoted to the further development of the institution, or otherwise towards the aid and promotion of scientific research. St. Helier's, Jersey ' W. Saville Kent GERMAN UNIVERSITIES 'X*HERE have been comparisons made recently both in -*■ this and in other journals between the Universities of Germany and those of this country, and as the university question is at present giving rise to much discussion, it may be useful to give some statistics with reference to the former. Such statistics are much more easily attainable for Germany than for England, as there are two German publications in which all the important information concerning the various universities of the empire is systematically arranged, viz., the DeutscJu Universitdts Kaletidar and the Deutsche akade?ntsches Jahrbiich. To obtain similar information concerning the universities of the United Kingdom it would be necessary to obtain a copy of the calendar of each uni- versity. Our statistics are obtained from the JahrbiicJi, which contains information not only relating to the uni- versities, but also to the technical and high schools, learned societies, and libraries of the country. Some such pub- lication is wanted here, and might be made to include not only our various universities and colleges, but also our principal public schools. The Jahrbuch includes, moreover, the Russo-German University of Dorpat, the Universities of Vienna, Graz, Innsbruck, Prague, Czer- nowitz, Basel, but these we shall not take into account, Germany has in all twenty-one universities, each comp'ete in all departments. The number of students matriculated and non-matriculated attending each, mostly in the 1876-77 semester was as follows : — Matriculated Students. •a u & (U Total. "o •3 % 0 % 1 s c 0 Berlin 139 IC03 281 1067 2107 4597 Bona J 63 200 118 312 36 829 Breilau 107 377 165 458 • 5 II22 Erlangen 136 37 102 147 422 Freiburg 41 64 128 60 36 329 Giessen^ — — — — 10 331 Go t ngen 71 324 122 474 991 Greilswald 32 89 235 142 9 507 Halle 190 150 103 439 16 898 Heidelberg 9 410 lOI 215 60 795 Jena 66 lOI 71 201 20 459 Kiel 47 14 73 78 II 223 Konigsberg 44 186 127 264 10 631 Lei izig ... ... 328 1 102 364 1 182 "3 3089 Marburg 49 65 104 164 4 386 Mun ch 7§ 357 440 3 408* 1280 Mun>ter 208 — 223 431 Rostock 24 35 31 54 144 Sirassburg 49 211 178 236 ** 26 700 Tubingen 29s 251 138 335' 6 1025 "Wiirzburg ISO 93 547 328 22 1040 2223 5069 3428 6787 2501 20229 Thus, then, there are about 18,000 matriculated stu- dents attending the twenty-one universities of Germany, under a teaching staff of about 1,300 paid professors, besides about 450 privat-docenten. Of the students, about one-third belong to the philosophical faculty, the faculty in which the sciences are included, Unfortu- ' In "Philosophy" are included the physical and natural scie«ces,_ ' The Giessen students are divided into Hessian and non-Hessian, noi. according to faculties. 3 Including loo students of pharmacy. 4 Inchiding 9 students of forestry. 5 Including 97 mathematical and natural science students, these being ?, saparate faculty et Strassburg. The figures are for 1875-6. 6 Including S3 students in political economy and 141 in natural science these subjects forming separate fa-rHlties at Tubingen, 104 NA TURE S^Dec. 6, 1877 nately, in very few cases is the number of students attending the scientific as distinct from the literary classes given, and only in one or two universities has science as yet been erected into a separate faculty. If we may take the two universities, Strassburg and Tiibingen, in which natural science forms a separate faculty as a criterion from which to judge of the number of students of science in the other universities, the proportion must be very large. In Strassburg, of the 236 students whom we have placed in the philosophical faculty, ninety- seven are students of science, and in Tubingen 100, or something like one-third of the whole philosophical faculty. Or again, if the number of science students is at all in proportion to the number of science- teachers, the position held by science in German universities is in striking contrast to its ros'tion in our universities and colleges. Of the profes- sors, among whom we do not count the privat-docenten, about one-half belong to the philosophical faculty, and of these again, nearly one-half are teachers of science, that is, in the philosophical faculty of the German univer- sities there is one teacher on an average to every ten stu- dents, and in science the proportion is considerably greater. In these estimates we do not take account of the medical faculty, in which, in most of the universities, there are several chairs which might well be classed as belonging to science generally. For example, the well-known anthropologist, Dr. Virchow, the conclusion of whose address at the German Association we give this week, is Professor of Pathology at Berlin, and has been able to bring the results of his special medical line of investigation to bear, in an im- portant way, upon his anthropological researches. Both in Berlin and elsewhere, other names of eminent medical professors might be mentioned who have not only them- selves made important contributions to science, but under whom students are encouraged to do so likewise. Of the nature and extent of the scientific teaching in German universities some idea may be formed from the subjects represented by the teaching staff at Berlin, which may fairly be taken as a type of the whole. In Berlin then we find that there are (excluding the privat-docenten) five professors of mathematics, two of astronomy, seven of chemistry, five of physics, three of geology, four of botany, two of zoology, one of meteorology, two of geography, one of anthropology, and one of agriculture — physiology and comparative anatomy being well repre- sented in the medical faculty, and we might well have included among teachers of science those who devote themselves to the scientific investigation of languages. But a mere statement of the number of teachers gives no adequate idea of the means at the command of a German University for training its students in science. The number of teachers in each subject secures that its various departments will be thoroughly worked out, and gives a student a chance of following out any specialty he may take up ; this is made still further possible by the number and variety of institutions, museums, laboratories, collections, &c., attached to each university, not to speak of its large and comprehensive library. In connection with Berlin alone there are twenty- three scientific " Anstalten," as they are called, for practi- cal investigation in connection with the various faculties. Had we taken the numerous Realschule and the high and polytechnic schools into account, where an education can be obtained quite equal to that obtainable at most of our universities and colleges, it would have been seen that higher education in Germany leaves little to be desired. And in reference to the subject of our leader this week, we would point to these Realschulen as embodying the German id^ a of what practical training should he. The carefully drawn-up time-tables of these schools are an mstructive study, showing, as they do, that general mental culture IS regarded as of the first importance in train- ing a youth for the work pf the worjd. The Jahrbtich gives a statement of income and expendi- ture in connection with only one or two of the universities. Some interesting details, however, on the contributions of the State to the universities, as well as on other points, were given in a recent number of the Academy by Prof. Ray Lankester : — " The sum expended by the North German States on the twenty universities belonging to them is annually more than 500,000/. The Imperial Government has ex- pended upon the new University of Strassburg alone 70,000/, in one year. The University of Leipzig alone re- ceives annually from the Saxon Government over 50,000/. There are eight universities in North Germany which are little, if at all, less costly, and there are eleven of smaller size which receive each from 8,000/. to 20,000/. annually. " In North Germany there is one university to every two million inhabitants ; in Austria there is one to every five miUions ; in Switzerland one for each million ; in England one to every seven millions. In the twenty North German universities there are 1,250 professors.^ In the British Islands we ought to have sixteen uni- versities and 1,000 professorships in order to come up to the same level in this respect as North Ger- many. The stipend (apart from fees) of a professor in a German university ranges from 100/. to 600/. a year. As a rule, at the age of five- and- thirty, a man in this career may (in Germany) count on an assured income of 400/. a year (with retiring pension). The expenditure on atten- dants, libraries, laboratories, and officials may be calcu- lated as being (in a well-conducted university) more than equal in amount to the total of the professors' stipends. Taking the average German professorial stipend at only 200/. a year, we find that 250,000/ must be spent annually on this item alone in the North German States. : " In order to equip and carry on sixteen universities in this country which should bear comparison with the Ger- man universities, we require not less than an immediate expenditure of 1,000,000/ sterling in building and appa- ratus, and an annual expenditure of from 500,000/. to 800,000/," When we add to the Government subsidy the income of the universities from other sources, the sum is enormously increased. The half-million, moreover, does not include the occasional grants of the Government for special purposes. Some idea of the magnificence of these was shown in our recent " University Intelligence," where it was stated that in the budget submitted to the present Prussian House of Deputies are the following items :— Erection of the Ger- man Industrial Museum, 998,000 mk. ; erection of a Polytechnic in Berlin, 8,393,370 mk, ; erection of an Ethnological Museum in Berlin, 1,800,000 mk. ; and for the Berlin University, erection of an Herbarium, 422,000 mk. ; of a Clinic, 1,955,000 mk. ; of a new building for a second Chemical Laboratory, as well as of a Technical and Pharmaceutical Institute, 967,000 mk. OUR ASTRONOMICAL COLUMN The Meteorite of July 20, i860.— The occurrence of the splendid meteor of November 23, which has probably been observed with sufficient completeness to allow of the determination of its path, while it remained visible, recalls a similar object which passed over the northern parts of the United States and adjacent parts of Canada, on the evening of July 20, i860, which was made the subject of investigation by the late Prof. J. H. Coffin, of Lafayette College, N.Y. Probably no one of these remarkable bodies has been more extensively observed, and we do not remember any case where the calculations have been more laboriously conducted, and with greater hope of reliable results. » i.e. we presume professors strictly so-called, exclusive of " privat docenten." Dec. 6, 1877] NA TURE 105 The "meteoric fire-ball," as Prof. Coffin calls it, was first seen moving in an easterly direction from a point nearly over the western shore of Lake Michigan, though it may have become luminous somewhat further to the west as the sky was clouded over that region. From thence it was watched until it disappeared out at sea in a south-easterly direction from the island of Nantucket. Its course was therefore about 1,300 miles, and it was seen for several hundred miles on either side of this track. Upwards of 230 descriptions of the meteor were collected, and upon the best of these Prof Coffin under- took the determination of the orbit, by an elaborate pro- cess detailed in his memoir, which formed No. 221 of the " Sm thsonian Contributions to Knowledge," entitled " On the Orbit and Phenomena of a Meteoric Fire-ball, seen July 20, i860." The various accounts of the meteor are printed in the memoir, and reveal some peculiar points of interest in its path. There were two "remarkable ruptures of the main body of the meteor," particularly near the meridian of 77" west of Greenwich, when it separated into two parts nearly equal in size which disappeared below the horizon, as one observer describes it, like a chain- shot. Considering that whatever might have been the orbit of the meteor before it became visible, its course while it was under observation, from being so near the earth, must have been controlled almost wholly by her attraction. Prof. Coffin mentions that the orbit he has investigated is not the path of the meteor in space, but the orbit relative to the earth, having the centre of our globe in one of its foci. Approximate elements having been obtained, azimuths and altitudes deduced from them were compared with those given by the various observations to ascertain what modi- fications of the elements were required in order to satisfy them. It was found that with certain corrections thus indicated the first orbit represented tolerably well most of the reliable observations to the west of 76" or 77°, near which the most easterly of the two points from which it was determined, was situated ; but further to the east the discrepancies between calculation and observation were "so great that they could be reconciled only by introducing changes in the elements of the orbit, one on the meridian of 77° and another near the meridian of 74°, ancj as Prof, Coffin remarks, it is worthy of note that it was in the vicinity of these points that observers report the violent ruptures of the body of the meteor, which seems to afford a rational explanation of the changes of elements found to be required. It was apparent that while the meteor descended rapidly towards the earth till it reached the meridian of about 74°, it afterwards rose, and the change was too great to be accounted for on the supposition that the meteor at that point attained the perigee of its hyper- bolic orbit. After the introduction of other considera- tions, it resulted that the path divided itself into three sections, '* the first and third of indefinite length, over only a small portion of which the meteor was visible, and the second an intermediate one, 160 miles long, where it was must brilliant." The elements for the three sections, as finally adopted, are : — Sec. I. Sec. II. Sec. III. Long, of perigee 294 57 ... 275 37 ... 201 2 ,, descending node... 332 56 ... 325 il ... 329 24 Inclination to ecliptic 66 12 ... 67 ID ... 66 26 Eccentricity 29984 ... 2-9817 ... 2 9921 Major semi-axis 2005-3 ... 2005"3 ... 2005-3 Perigeal dibtance 4007 ... 3974 ... 3995 The major semi-axis and the perigeal distances are ex- pressed in miles. According to these elements. Prof. Coffin concludes that the meteor entered the sphere of the earth's attraction from the direction of the constella- tion Sextans, in about R.A. 148°, N.P.D. 87°, and left it toward a point in R.A. 355°, N.P.D. 121°. The Planet Mars and B.AC. 8129. — The near ap- proach of Mars to the seventh-magnitude-star, B.A.C. 8129, appears to have been observed pretty generally. Taking the^mean place of the star from the Washington Catalogue of i860, its apparent position on the evening of November 12 is found to be R.A. 23h. 14m. 24-375., N.P.D. 96° 34' 22 '-5. By Leverrier's tables the place of Mars at 6h. Greenwich time and the hourly motions were : — RA 23h. 1400. 24S-9I -i- 3S-473/?. N.P.D 96° 34' 25" -I - 30" -49/. Taking account of parallax, the star at 6h. would be on an angle of 3i9''-4, distant from planet's centre, i7"-8, b/ calculation, as seen at Greenwich. Probably the actual approach was not quite so close. The Binary-star Castor.— Dr. Doberck, of Col. Cooper's Observatory, Markree, whose investis^ations relating to the orbits of the revolving double-stars have been on several occasions referred to in this column, has corrected the elements of the fine binary a Geminorum, given by Thiele in 1859, by measures to 1877 inclusive. Thiele's period of revolution was 997 years, Dr. Doberck's calculation gives 1,001 years, and the comparison with observations, from those of Bradley and Pound in 17 19 to the present year, exhibits no larger differences than are to be attributed to unavoidable errors, or in one or two cases, bias on the part of the observer. The new elements are as follow : — Passage of the peri-astre 174975 Node Node to peri-astre on orbit Inclination Eccentricity Semi-axis major Revolution 27 46 (meridian of 1850). 297 13 44 33 03292 7"-43 1001-21 years. This orbit gives, for 1878-0, position 234°-9, distance 5"76. Transits of the Shadow of Titan across the Disc of Saturn. — Mr. Marth has drawn attention to the following dates of transit of the great satellite's shadow, as the only opportunities for obser-zation uniil the year 1891 : — December 9, about 6^h. Greenwich time, December 25, about 5fh., and January 10, about 5h. The "Nautical Almanac," 1881. — As usual the Nautical Almanac was published in November, the last volume being for the year 1881, which does not appear to be one distinguished by any particular astronomical phenomena. The two solar eclipses on May 27 and November 21, the first partial, the second annular, aie both invisible in this country, and the line of annularity in the November eclipse runs at great south latitude. The total eclipse of the moon on June 11 will also be invisible here, while in the partial eclipse on December 3 (magnitude 0-97) the moon will rise at Greenwich aboui twenty minutes after first contact with the shadow. A transit of Mercury on November 7, will be wholly in- visible in this country, the first external contact (geo- centric) taking place at loh. i6m. 13s., and the last at I5h. 37m. 41S. mean times at Greenwich. The list of visible occultations does not contain any planet, nor any star over the third magnitude. The list of standard stars is on the same scale as for the year 1880, and numbers close upon 200. The Naulical Almanac circ\i\a.tes to the extent of more than 20,000 copies, inclusive of the number appropriated for the use of the Royal Navy. OLE RUMER WHEN Newton's "Principia" raised the theory of astronomy to a height not previously dreamt of, practical a-^tronomy was still where Tycho Brahe left it almost a century before. Such was the respect paid to io6 NA TURE \Pec. 6, 1877 the memory of that great man that Hevel in Danzig carried cut Tycho's ideas about his observatory, and rejected all the improvements that had since originated, amongst which was the application of the telescope to astro- nomical observations. The obstinacy with which Hevel refused to adopt this invention appears strange to us now, but we must remember the great accuracy which was then obtained by pinnules alone. Tycho had reduced the probable error of astronomical observations from ten minutes to one, and some of Hevel's observations have been found to be affected by errors of less than half a minute of arc, results which show that the old astro- nomers were in possession of a skill in handling their apparatus which has since been lost. It should also be taken into account that the telescopes of Hevel's day were generally of Dutch construction, and Kepler's tube, with wires in the field to mark the centre, was first brought into general use by Auzout and Picard about the end of the century. . Of hardly less importance was the application of the pendulum to clocks, which from that time have been used as astronomical instruments. They had in Tycho's observatories been used merely to show what o'clock it was when observations were made, but never to determine differences of right ascension. With sufficiently good clocks it was possible to determine the positions of the stars by observa- tions in the meridian alone, and it was no doubt Picard who first became aware of the immense advantage of this. Consequently he solicited Go- vernment for a large mural quadrant, but Cassini was then called in from Italy, and no notice was taken of the request made by Picard, who, unfor- tunately for the practical astronomy of France, was not thought much of by the court of Louis XIV., his important, but modestly-conducted researches being eclipsed by Cassini's brilliant discoveries. Had Picard got the direction of the Royal Obser- vatory in Paris he would have been able to make further improvements in the construction of instru- ments ; but with no sufficient means at hand, he ascribed the partial failure of his attempts to the small size of his instruments. A mural quadrant like Tycho Brahe's, but furnished with a telescope, was first fixed at the observatory when Picard died.' Flamsteed. and Sharp adopted the methods just as Picard left them and with all their draw- backs. They used the quadrant both for right ascensions and declinations. Theit observations may perhaps be said to be twice as accurate as Hevel's naked-eye observations. This was the state of practical astronomy when Romer raised it to a height which was not sur- passed before Bessel. Ole Romer was born in Aarhus on September 25, 1644. Thence he came, 1662, to Copenhagen, where he studied mathe- matics and astronomy under Erasmus Bartholin, whom he subsequently assisted. As has already been pointed out, Tycho's observations continued to be consulted by astronomers, and in 1671 Picard went to Denmark to determine the difference between the longitude of Uraniburg and Paris.' There he found Romer occupied in revising Tycho's manuscripts, and he secured his assistance in the observations on Hveen, and when Picard returned to France he procured Romer a place as assistant at the observatory of Paris. There his talents did not fail to be appreciated, and he was soon elected a member of the Academy. It was in Paris that Romer discovered the gradual propagation of light from QVADRANS MVRALIS SIVE TICHONICUS. ' This interesting irstru lent is represented in Fig. i. It was cast wholly in bi ass and fi>ed with strong iron screws as exactly as possible in the meridian in the south-western room of the ground-floor of Uraniburg. Its radius was about six feet, and it could by means of transversals be read off to ten seconds of arc It had in a hole in the south-western wall in the centie a g>lt cylinder and two pinnules movable along the edee, which were so constructed tbat the slit could be opened or closed more or less according to the faintness or brightntss of the objects to be observed. Tycho Brahe who, in contiadist notion to Ole Romer, was not only anxious about the quality but also about the appearance of his instruments, had ornamented the large empty s]^ ace of the quadrant with the splendid picture shown in the plate. He is here depicted in his usual attire. At his feet is lying one of his favourite huntir.g-dogs, more as a symbol of ingenuity than as a symbol of nobility. Behind him are small poi traits of King Frederick and Queen Sofie. This was painted by John of Antwerp and is more like him than any other image, but the space contained also an architectonic picture by Steenvinkel, somewhat reduced as if at a distance. In the upper Story are reprcseiited some of his most celebrated instruments, in the middle story the library mside with the large celestial globe ana his pupils occupied with their studies, and in the cellar the chemicti laboratory. On the plate is seen a young man observing through one ct the pinnules, anotttr is watching the clocks, while a third is noting down their remarks at a table. Tj'cho Brahe's image seems as if admonishing and instructing them in their work. Fig. I. observations of the eclipses of the first satellite of Jupiter. His results, which were not very exact, were however, contested by Cassini and most other authorities for a long time after. Indeed, the theory of the moti 'n of the satellites was at that time so little elaborated, t lat similar conclusions might be questioned all the more a - they had been deduced from observations of the firs satellite alone. Romer shortly afterwards discovered the epi- cycloid, and published a paper on the prope- form of toothed wheels, and descriptions of a Jovila )ium and Saturnilabium ; he afterwards invented differen: kinds of ' On this occasion fire-signals were for the first time made use of for the determination of longitude. A fire was lit on the top of the astr jnomica tower in Copenhagen. There Picard eclipsed it at rsgular in-e c/;V^ knowledge, but there is a certain intermediate part — I mean ^f/^f/^— which also exists in science, with this difference only, that here it is applied to other things than in the case of religious belief. It is somewhat unfortunate, in my opinion, that the expression belief has been so completely monopolised by the church, that one can hardly apply it to any secular object without being misunderstood. In reality there is a certain domain of belief even in science, upon which the single worker no longer undertakes to prove what is transmitted to him as true, but where he instructs himself merely by means of tradi- tion, just what we have in the church. I would like to remark on the contrary — and my conception has not been contradicted by the church — that it is not belief alone which is taught in the church, but that even ecclesiastical dogmas have their objective and their subjective sides. No church can avoid developing in the three directions I have pointed out : in the middle the path of belief, which is cerlainly very broad, but on the one side of which there is a certain quantity of objective historical truth, and on the other a variable series of subjective and often very fantastic ideas. In this the ecclesiastical and the scientific doctrines are alike. The cause of this is that the human mind is a simple one, and that it carries the method which it follows in one domain finally into all the others as well But we must be aware at all times how far each of the directions mentioned extends in the different domains. Thus, for instance, in the ecclesiastical domain — it is easier to show it in this one — we have the real dogma, the so-called positive belief; about this I need not speak. But each creed has its peculiar historical side. It says : this has happened, this has occurred, these events have taken place. This historical truth is not simply handed down, but in the garb of an objective truth it appears with certain proofs. This is the case with the Christian religion just as much as with the Mohammedan, with Judaism just as much as with Buddhism. On the other side we find the left wing as it were, where subjectivity reigns ; there the single individual dreams, there visions come and hallu- cinations. One religion promotes them by special drugs, another by abstinence, &c. Thus subjective individual currents are deve- loped, which occasionally assume the shape of perfectly inde- pendent phenomena existing by the side of and apart from the previous ecclesiastical domain, which at other times are rejected as heresies, but which often enough lead into the large current of the recognised church. All this we find again in natural science. There too we have the current of the dogma, there too we have the currents of the objective and subjective doctrines. Conse- quently our task is a compound one. First of all we always try to reduce the dogmatic current. The principal aim of science has for centuries been to strengthen more and more the right, the conservative side. This side, which collects the ascertained facts with the full consciousness of proof, this side, which adheres to experiment as the highest means of proof, this side, which is in possession of the real scientific treasury, has always grown larger and broader, and this principally at the expense of the dogmatic stream. Really, if we only consider the number of natural sciences which since the end of last century have grown and now flourish, we must admit that an almost incredible revolution has taken place. There is no science in which this is so eminently evident as in medicine, because it is the only science, which has a continuous ' Address delivered at the Munich meeting of the German Association, by Prof. Rudolf Virehow, of Berlin. Continued from p. 94. history of nearly 3,000 years. We are, so to speak, the patriarchs of science, inasmuch as we have the dogmatic current at its longest. This current was so strong, that in the early part of the middle ages even the catholic church embraced it, and the heathen Galen appeared like a father of the church in the ideas of men ; indeed, if we read the poems of that period, he often presents himself exactly in the position of a church dignitary. The medical dogma went on until the time of the Reformation. As contemporaries of Luther, Vesal and Paracelsus came and made the first grand attempts at reduction, they drove piles into the dogmatic stream, constructed dykes by its sides, and left only a narrow fair- way to it. Beginning from the sixteenth century it has grown narrower and narrower every century, so that finally only a very small channel has remained for tlxe therapeutists. Thus vanishes the lordliness of the world. Only thirty years ago the Hippocratic method was spoken of as something so sublime and importantthat nothing moresacred could be imagined. Nowadays we must own that this method is annihi- lated nearly down to its root. At least, a good deal of imagina- tion is necessary if we say that any physician of the present day acts as Hippocrates did. Indeed, if we compare the medicine of to-day with the medicine of the year 1800— accidentally the year 1800 marks a great turning-point in medicine — then we find that our science has undergone a complete reformation during the last seventy years. At that time the great Paris school was formed, immediately under the influence of the French Revolution, and we must admire the genius of our neighbours that enabled them to find all at once the fundamental basis of an entire new discipline. If now we see medicine continue its development in the greater breadth of objective knowledge, we will never forget that the French were the precursors, as in the middle ages the Germans were. By our own example I only wished to show you shortly what changes both the methods and the storehouse of knowledge undergo. I am convinced that in medicine, at the end of the present century, only a sort of clay-pipe system will have remained, through which the last weak waters of the dogmatic stream may move — a sort of drainage. For the rest the objective current will probably have entirely consumed the dogmatic one. Perhaps the subjective one will remain as well. Perhaps even then many an individual will dream his beautiful dreams. The field of objective facts in medicine, great as it has become, has yet left such a number of lateral fields, that for anybody who wants to speculate, plenty of opportunities offer daily. And these opportunities are honestly made use of. A multitude of books would remain unwritten if only objective things were to be communicated. But the subjective wants are still so great, that I believe I am justified in maintaining that of our present medical literature about one half might safely remain unpublished, with- out doing any damage worth mentioning to the objective side. Now when we teach, in my opinion, we ought not to look upon this subjective side as an essential object in the doctrine. I believe I naw belong to the oldest professors of medicine ; I have taught my science now for over thirty years, and I may say that during these thirty years I have honestly striven by myself to free my mind more and more from all subjective tendency, and to get more and more into the objective current. Nevertheless I openly confess that I find it impossible to give up subjectivity altogether. Every year I see again and again that even in points, where I had believed myself to be entirely objective, I ^till retained a large number of subjective ideas. I do not go so far as to make the inhuman demand that everybody is to express himself entirely without any subjective vein, but I do say that we must set ourselves the task to transmit to the students the real knowledge of facts in the first place, and if we go further, we must tell them each time : " but this is not proved, but this is my opinion, my idea, my theory, my speculation.' This, however, we can only do with those who are already educated and developed. We cannot carry the same method into the elementary schools, we cannot say to each peasant boy, " This is a fact, this we know, and that we only suppose. On the contrary, that which is known, and that which is only sup- posed, as a rule get so thoroughly mixed up that that which is supposed becomes the main thing, and that which is really known appears only of secondary importance. Therefore we who support science, we who live in science, are all the more called upon to abstain from carrying into the heads of men, and most of all into the heads of teachers, that which we only suppose. Certainly, we cannot give facts only as raw material, that is impossible. They must be arranged in a certain systematic 112 NATURE {Dec, 6, 1877 order. But we must not extend this arrangement beyond what is a^^solutely necessary. This is a reproach which I cannot help making against Prof. Nageli as well. Prof. Nageli has discussed, certainly in the most measured way and — you will notice this if you read his address — in a thoroughly philosophical manner, the difficu't qiustions which he has chosen as subjects for his address. Nevertheless he has taken a step which I consider extremely dangerous. He has indeed done in another direction what is in one way done by generatto aquivoca. He asks that the mental domain ^hall be extended not only from animals to plants, but that finally we shall actually pass from the organic world into the inorganic with o ir conceptions of the nature of mental phenomena. This method of thinking, which is represented by great philosophers, is natural in itself. If anyone wants by any means to connect mental phenomena with those of the rest of the universe, then he will necessarily come to transfer the mental processes, as they occur in man and the animals of highest organisation, to the lower and lowest animals ; afterwards a soul is even ascribed to plants ; further on the cell thinks and feels, and finally he finds a passage down to chemical a^oms, which hate or love one another, seek one another, or flee from one ano'her. All this is very fine and excellent, and may after all be quite true. It may be. But then, do we really want, is there some positive scientific necessity, to extend the domain of mental phenomena beyond the circle of those bodies, in which and by which we see them really happening? I have no objection if carbon atoms have a mind as well, or that they obtain a mind in thfir union with the pla«tidule association, but / do not knno in n'hat I am to rerognise this. It is simply playing with words. If I declare attrac'ion and repulsion to be mental occu-rences, to be mental phenomena, then I simplv throw the mind (ftie Psych'') out of the window'; then the mind ceases to be mind. The phenomena of the human mind may eventually be explainei in a chemical way, ^ut for the present, I t^ink, it is not our task to mix up the-e donnains. On the contrary, it is our duty to keep tt-em stric'ly where we understand th^m to be. And as I have always laid stress upon thi=, that we should not in the first line try to find the trinntion fmm the inoi'ganic into the organic, but that we should first of all determine the contrast b^tween the inor- gani'- and the oreanic, and carry on our investigations among those contracts in the same way, I now rraintain that the only way to progress — and I hold the firmest conviction that we shall not advance at all otVierwise — is to limit the domain of mental phenomena where we reallv perceive ment^al phenomena, and not to suppose mental phenomena, where perhaps thev may be, but where we do not notice any visible, audiSle, sensible, in one word, perceptible phenomena, which we might call mental ones. There is no doubt that for us the whole sum of mental pheno- mena is attached to certain animals, not to the totality of all organic beings, not even to all animals generally, and I maintain this without hesitation. We have no reason yet to say that the lowest animals possess mental characteristics ; we find them only with the higher animals, and with perfect certainty only with the highest. Now I will admit with pleasure that certain gradations, cer- tain gradual transitions, certain points can be found, where from mental phenomena one gets to phenomena of simply material or physical nature. I certainly do not declare that it will never be possible to bring psychical phenomena into immediate connection with physical ones. All I say is, that at present we are not justified in setting down this possible connection as a scientific doctrine, and I must distinctly oppose the attempts to enlarge cur doctrines prematurely in this manner, and to bring again and again into the foreground as a po-iitive statement what we so often proved a useless problem. We must distinguish strictly between what we want to teach and what we want to investigate. What we investigate are problems. We need not keep them to ourselves ; we may communicate them to the whole world and say. There is the problem, this is what we are trying to find ; like Columbus, who, when he started to discover India, made no absolute secret of it, but who eventually did not find India, but America. And the same happens to us not rarely. We start to prove certain problems which we suppose to be perfectly correct, and in the end we find something quite different, which we never expected. The investigation of such problems, in wh'ch the whole nation may be interested, must be open to everybody. That is the liberty of research. But the problem is not at once to be the object of ins'tuction. When we teach we must confine ourselves to those smaller domains which are already so large, and wh'ch yre have ac'ually mastered. Gentlemen, I am convinced that only with a resignation oi this kind, which we impose on ourselves, which we exercise towards the rest of the world, shall we be enabled to conduct the fight aga'nst our enemies with a victorious result. All attempts to transform our problems into doctrines, to introduce our theories as the basis of a plan of education, particularly the attempt simply to depose the church, and to replace its dogma by a religion of descent without further trr uble, these attempts, I say, must fail, and their failure would at the same time br ng the greatest dangers upon the position of science generally. Therefore let us be moderate, let us exercis* resignation, so that we give even the most treasured problems which we put forth, always as problems only, and that we say it a hundred and again a hundred times : " Do not take this for confirmed truth, be prepared that this may perhaps be changed j only for the moment we are of opinion that it may be true. " By way of illustration I will add another example. At this moment there are probably few naturalists who are not of opinion that man is allied to the rest of the animal world, and that a connection will possibly be found, if indeed not with apes, then perhaps in some other direction, as is now the opinioii of Prof. Vogt. I acknowledge openly that this is a desideratum of science. I am quite prepared for it, and I would not for a moment wonder nor be alarmed if the proof were found that the ancestors of man were vertebrate animals. You know that just at present I work by preference in the field of anthropology, but yet I must declare that every step of positive progress which we have made in the domain of prehistoric anthropology, has really moved us further away from the proof of this connection. At this moment anthropology studies the question of fossil man. From man in the present "period of creation" we have descended to the quaternary period, to that period when, as Cuvier maintained with the greatest confidence, man never existed at all. Nowadays quaternary man is a generally accepted fact. Quaternary man is no longer a problem, but a real doctrine. Bat tertiary man is a problem — of course a problem which is ahcdy in a stace of material discussion. There are objects already about which discus- sions are going on as to whether they may be admitted as proofs for the existence of man during the tertiary period. We do not merely speculate on the subject, bat we discuss certain objects, whether they may be r^coi^nised as witnesses for the activity of man during the tertiary period. The question raised is answered differently according to whether these objective material elements of proof are considered sufficient or not. Even men who, like Abbe Bourgeo's, are decided ecclesiastics, are convinced that man has lived during the tertiary period ; for them tertiary man is already a doctrine. For us, who are of a more critical na'ure, tertiary min is still a problem, but, as we must acknowledge, a problem worthy of discussion. Let us therefore for the present remain at quaternary man, whom we really find. If we stu ^y this quaternary, fossil man, who ought after all to stand nearer to our ancestors in the series of descent, or rather of ascent, we find a man just the same as we are ourselves. Only ten years ago, when a skull was found, perhaps in peat or in lake dwellings, or in some old cave, it was believed that wonderful marks of a wild and quite undeveloped state were seen in it. Indeed we v/ere then scenting monkey air. But this has died out more and more. The old troglodytes, lake inhabitants, and peat people turn out to be quite a respectable society. They have heads of such a size that many a person living would feel happy to possess one like them. Our French neighbours have certainly warned us not to conclude too much from these big heads ; it may be possible that they were not filled only with nerve- substance, but that the old brains had more intermediary tissues than is the case now-a-days, and that their nerve-sub- stance in spite of the size of the brain, remained at a low state of development. However this is only a friendly conversation which to some extent is held as a support of weak minds. On the whole we must really acknowledge that all fossil type of a lower human development is absolutely wanting. Indeed if we lake the total of all fossil men that have betn found hitherto and compare them with what the present offers, then we can maia- tain with certainty that amongst the present generation there is a much larger number of relatively low-type individuals than amongst the fossils hitherto known. That only the highest geniuses of the quaternary period enjoyed the gool fortune of being pre- served for us I do not dare to suppose. As a rule we draw con- clusions from the condition of a single fossil object with respect to the majority of others which have not been found. But I will not do this. J will not maintain that tlip whole race was as Deed, 1877] NATURE 1 1 good as the few skulls which were found. But I must say that one fo<^sil monkey-skull or man-ape skull which really belonged to a human proprietor has never been found. Every addition which we have obtained in the material inventory of objects for dis- cussion has moved us further away from the problem to be solved. Now of course we cmnot avoid the consideration that perhaps it was on some quite special spot of the earth that tertiary man lived. This is quite possible, since during the last few years the remarkable discovery has been made in North America that the fossil ancestors of our horses occur in countries from which the horse had entirely disappeared for a long time. When America was discovered there were no horses there at all ; in the very place where the ancestors of our horses bad lived no living horse had r mained. Thus it may also be that tertiary man has existed in Greenland or Lemuria, and will again be brought to light from under the ground somewhere or other. But as a fact we must positively acknowledge that there is always a sharp limit between man and the ape. We cannot teach, we cannot designate it as a revelation of science, that man descends from the ape or from any other animal. We can but designate this as a problem, m ly it seem ever so probable and may it lie ever so near. We ought to be sufficiently warned by the experiences of the past, at a time when we are not justified in drawing conclusions, not unnecessarily to burden ourselves with the obligaiion, or yield to the temptation of drawing them all the same. Look you, gentlemen, it is in this that the difilicultv lies for every naturalist who speaks to the world at large. Whoever speaks or writes for the public, ought, in my opinion, doubly to examine just now, how much of that which he knows and says is objec- tive truth. He ought to try as much as possible to have all inductive extensions which he makes, all progressing conclusions by the laws of analogy, however probable they may seem, printed in small type underneath the general text, and to put into the latter only that which really is objective truth. In that case we might perhaps succeed in gaining an always increasing circle of followers, in obtaining an always mcreasing number of lellow- workers, and in causing the educated public to continue to take pttrt in that fertile manner in which it has already taken part in many domains. Otherwise, gentlemen, I fear that we overrate our power. Certainly old Bacon said with perfect justice, scientia est pctentia, knowledge is power. But he has also defined knowledge, and the knowledge which he meant was not speculative knowledge, not the knowledge of problems, but it was the objective knowledge of facts. I think that we should abuse our power, we should endanger our power, if in our teaching we do not fall back upon this perfectly justified, perfectly safe, and impregnable domain. From this domain we may as investigators make our excursions in the direction of problems, and I am convinced that every attempt of this kind will then find the necessary safety and support. AMERICAN SCIENCE 'T'HE principal paper in the American Journal of Science and -^ Arts for November, is Prof Marsh's able address at the recent meeting of the American Association, on the Introduction and Suc- cession of Vertebrate Life in America, which we have givenat length. — Discussing the question, Is the existence of growth rings in the early exogenous plants proof of alternating seasons ? Dr. Warring concludes from observations, that some exogens form rings at intervals much less than a year ; others require intervals of several years, and some form no rings. The presence or absence of rings in exogens occurs in all climates. Large and well- defined rinjjs are found where there is absolutely no appreciable variation of temperature or moisture throughout the year. An exogen naturally forming rings will continue to form them, although the climate become uni'orm throughout the year. Thus the existence of these markings in ancient flora gives no informaton as to the existence at that time of seasons, and so far as they are concerned we are left free to adopt any conclusion as to inclination of the earth's axis, which may appear most reasonable. — Some years ago Prof. Newcomb showed ttiac the improvements introduced into the theory of the moon's mean mot on by Hanssen's lunar tables did not extend to ths inequalities of long period in that motion. Wnile Hanssen, by an empirical term had secured a very good agreement with observations Irom 1750 to i860, this aLreement was found to have been obtained by sacrificing the agreement before 1750, and the moon had then begun to deviate from the tables at such a rate that they could not continue satisf^actorily to represent the observations. Prof. Newcomb has since attempted a complete discussion of all recorded observations of any astronomical value before the year 1750, and his suspicion has been entirely confirmed. The results of this examination are communicated. Comparing a theory of the moon's mean motion founded on gravity alone, with the observations, he is led to suppose thai; the deviations may be due to the action of some of the bodies of the solar system. He corrects Hanssen's term by an empirical addition. — Prof. Dana contributes to the number a rote on the Helderberg formation of Bernardston, Massachusetts, and Vernon, Vermont, and Mr. Mallet describes " Serpylite," a new niobate, from Amherst County, Virginia. The New York Tribune states that the Johns Hopkins Scien- tific Association has recently been organised in Baltimore. Prof. Sylvester is president. Prof. Remsen, vice-president, Dr. Story, secretary. A great feature in the programme is that the essays presented are to be short and concise, and to contain the par- ticulars of original research exclusively. There is also to be a discussion of new scientific publications, both foreign and domestic, at the meetings, of which the first has been held, with a score of members present. Under date November 20, the 7>//5;///^ has the following telegram from Washington : — Messrs. S. H. Scudder of Cambridge, and F. C. Bowditch, of Boston, have just returned from a two months' tour in Colorado, Wyoming, and Utah, where, under the direc- tion of Dr. Hayden, they have been exploring for fossil insects and collecting specimens especially in the high regions. They report having secured many specimens of fossil insects at different points along the railways from Pueblo to Cheyenne, and from Cheyenne to Salt Lake, as well as at Lakin, Kansas, and Gar- land, and Georgetown, Col., and in various parts of the South Park and surrounding region. Their time was so limited that they were unable to visit White River and explore the beds of fossil insects] known to exist there. Ten days were spent at Green River, and in that vicinity, in exploring the tertiary strata for fossil insects, but with very unsatisfactory results. Near Florisante the tertiary basin was found, to be exceedingly rich in insects and plants. Mr. Scudder spent several days in the careful survey of this basin, and estimates that the extent of the insect-bearing shales there is at least fifty times as great as that of those in Southern Bavaria. Six or seven thousand specimens of insects, and 2,000 or 3,000 of plants have already been received from Florisante, and as many more are expected before the close of the year. Arrangements were also made with persons who have found a new and rich deposit of fossils in the tertiary strata in Wyoming to forward all the specimens obtained there. Mr. Scudder believes that the tertiary strata of the Rocky Mountain region are richer in the remains of fossil insects than any others in the world, and that within the next few months the amount of material at hand for the study of the subject will be greater than was ever before possessed by any single naturalist. Prof. Joseph Leidy, the comparative anatomist and microscopist, has also recently returned from his second visit to the west, under the direction of Dr. Hayden. His field of operations during the past season was the country about Fort Bridger, Unitah Mountains and the Salt Lake Basin. The specimens he has collected comprise the lowest and simplest forms of animal life, the most minute requiring high microscopic power to distinguish their structure. THE METEOR WE have received some further communications concerning this remarkable phenomenon, and some interesting details concerning a similar body will be found in our "Astronomical Column." Mr. A. O. Walker writes from Chester:— In reading the notice of the meteor of November 23 in Nature, vol. xvii. p. 94, I am surprised to see no mention of any report from it. As I only heard it without seeing it I send you the notice of it from my diary, written immediately after the occurrence : — " About 8.30 P.M. heard a loud report like that of a cannon (say 32 lbs.), fired about 200 yards off, which shook the house, and the servants saw a bright flash. The sky overhead was quite clear and only cloudy on tfie horizon south and east. Thought ic was the explosion of an aerolite." Next day 1 made inquiries and added the following : — " Parry and Field said the flash was blue, and five minutes 114 NATURE \_Dec, 6, 1877 elapsed between the flash and bang. Parry's girl was outside, and came in crying ; said she had seen ' a very funny kind of lightning.' Parry remarked it shook his door." The two men named above are in my employ, and live about 300 yards from my house. Some friends of ours living about two miles from us also saw the flash and heard the report, but the latter not so loud as we did. They described it as sounding as if a bird had flown against the window." I give the above extracts verbatim, as first impressions, unin- fluenced by what one hears or reads subsequently, are much the most valuable. Dr. S. Drew, of Chapeltown, Sheffield, writes as follows : — I send you the following calculations as to the meteor of November 23. They may interest some of your readers. The estimates are only intended as approximate, as the observations at different points of view were too vague for much accuracy, and indeed, in two instances, obviously quite unreliable. The visible course of the meteor appears to have been from a point about 1 50 miles above the town of Worksop to the Irish Channel, north-west of Liverpool, probably nearly half-way between Liverpool and the Isle of Man — a direction from east by south to west by north, the horizontal distance traversed being rather over 100 miles and the perpendicular 150 miles. The size of the fire-ball before breaking up was about 150 yards in diameter. By this is meant the size of the luminous sphere, not that of the actual bolide, which would be much less. The rate of motion was near twenty miles per second in horizontal, and thirty miles in perpendicular ; as this in horizon- tal is little more than would be caused in appearance by the orbital and diurnal motion of the earth, it is evident that the proper motion of the meteor was nearly perpendicular to the earth's surface ; and, if belonging to the solar system, it must have moved in a very eccentric orbit, stretching far beyond that of the earth. The meteor broke at an elevation of about fifty miles, and then appeared much larger. The fragments must have dropped into the sea. Was it seen from Ireland or the Isle of Man ? S. A. K. writing to the Manchester Courier from Black- pool states that about 8.30 P.M. on the 23rd he beheld a ball of a pale blue colour shoot across the sky from east to west, followed by a train of rainbow lines, brilliant beyond descrip- tion. " It was over in a moment ; but as I and several others tood discussing the phenomenon we had just witnessed, two muffled booms as of far-distant cannon were distinctly heard in the west, after an interval of two or three minutes." Capt. Tupman writes from the Royal Observatory, Greenwich, to the Times: "There is reason to suppose that the great meteor which appeared at 8.20 p.m. on Friday last (November 23) fell into the sea near the mouth of the river Dee. From its splendour it was probably seen by many persons near the shores of North Wales, Cheshire, and Lancashire, whose observations would be of the greatest value ; and I venture to solicit the publicity of your columns in order that such observations may be forwarded here. On Tuesday night (Nov. 27), at 10.26, G.M.T., I observed another pass slowly from a point about 6° over Castor to 5° left of Sirius. It remained in sight fifteen or sixteen seconds, deter- mined by counting. Towards the end it became faint, of a dull red colour, and moved with extreme slowness. I have no doubt it must have appeared very large to observers near Dover and in Normandy, and it is to be hoped^ its path has been recorded elsewhere." A meteor was observed at Strassburg on November 23, the very day when the meteor was observed in England, but the time was a little after six o'clock (local time), and the direction from north to south. A violent detonation was heard, but without any resemblance to that of thunder. The light was as vivid as ordinary lightning at Strassburg. A witness states that he saw the meteor falling at a small distance from him (three or four metres) in a wood belonging to the Chevaudier de Valdrome on the new road leading from Lorquin to the French frontier. All the trees were illuminated as if by daylight. It is not reported by the Strassburg Gazette whether any stone was found on the spot. UNIVERSITY AND EDUCATIONAL INTELLIGENCE Oxford. — The Brackenbury Scholarship in physical science has been awarded to Mr. Cunningham, Balliol College. London. — The Council of University College have) awarded the Sharpey Physiological Scholarship to Mr. Patrick Geddes and the Joseph Hume Scholarship in Political Economy of 20/. per annum for three years to Mr. J. G. Schurman. Edinburgh. — A public meeting, under the presidency of the Right Hon. the Lord Provost, was held on the 29th nit. at Edinburgh to advocate the claims of the Edinburgh University Buildings Extension Scheme. The cost of the new medical school, &c., will be about 187,000/., and of that sum 82,000/. has been subscribed by the public and 80,000/. has been promised by Government on condition that the remaining 25,500/. be sub- scribed before the end of next year. It was announced that about 10,000/. of this has been promised, leaving upwards of 14,000/. still to be raised. In support of the appeal it was men- tioned that in some class-rooms there is not sitting room for the students. The number of students is increasing every year, there being at present enrolled 212 more than at the same time last year, so that before the summer session is over there will probably be close on 2,500 students matriculated. The first meeting of the fourth session of the Chemical Society of the University was held in the University on November 28, the president, Prof. A. Crum Brown, in the chair. The president gave an introductory lecture on the "Life and Works of Dr. Joseph Black." The following office-bearers were elected for the ensuing seasion : — President — Prof. A. Crum Brown ; Vice- Presidents— J. Gibson, Ph.D., F.R.S.E., W. Inglis Clark, B.Sc. ; Secretary — ^J. Adams ; Treasurer — C. Maxwell, R.N. The society numbers fifty-two members, and ten new members were proposed. Manchester. — A Chemical Society has been commenced at the Owens College. The society is intended to include all students of science at the College — Dalton Scholars, Associates, and a few others connected now, or in the past, with the Science Classes of Owens College. The society was opened on Wednesday evening by an address from Prof. Thorpe, F. R.S. on "Robert Boyle and the Sceptical Chemist." The Syllabus of the society for the sessioa is as follows : — " Are the Elements Elementary?" by Mr. Pattison Muir; "Graham," by Mr. P. P. Bedson, B.Sc. ; " Berzelius," by Mr. J. K. Crow, B.Sc. ; "Alkali Manufacture," by Mr. Bevan : "Crystallisation," by Mr. Baker; "Liebig," by Mr. C. F. Cross ; " Valensy," by Mr. O'Shea ; " Chemical Industry of Japan," by Mr. Siguira ; and a paper, subject not settled, by Prof. Gamgee. It is hoped and believed that the society will tend to increase the interest in scientific pursuits already manifested by members of the College. France. — A number of important measures have been taken by the French Minister of Public Instruction for fostering the zeal of students and professors in the several French faculties. By a decree issued on November 5 a number of scholarships hare been created in each academy at the expense of the public exchequer. In future years scholars are to be appointed after having passed special examinations similar to those for exhibi- tions in the English universities. Exceptions are created in favour of students who have been particularly successful in taking their preliminary degrees and have published approved papers in the Academical Transactions, or have rendered special services in tuition. For the present year the different scholar- ships are to be granted by a special commission. Three of these commissions have been established — one for letters, another for science, and the third for medicine. These scholarships are to be continued only for a limited time, varying from two to four years, but are to be stopped at once if the scholar does not give sa'isfaction to the professors or lecturers. A part of these scholarships is to be granted to candidates for the mastership of arts (Licencie-es-Lettresandes-Sciences), and another part to the masters in several faculties wishing to take the highest honours in their respective faculties. By another decree, published on the same day, M. Brunet has created a number of lectureships styled "conferences." A number of the lecturers are to act as public tutors, helping public professors in their duties. Other lectureships are to be granted to professors teaching supple- mentary sciences which, up to the present time, have not come within the limits of the official programme. The salary of all ot them is 120/., and they are to be appointed yearly from among doctors or members of the academies. In some peculiar cases Masters of Arts are eligible to these lectureships. The new organisation is expected to work during the present classical year. Dec. 6, 1877] NATURE 1 1 SOCIETIES AND ACADEMIES London Geological Society, November 7.— Prof, P. Martin Duncan, F.R.S., president, in the chair.— Stephenson Clarke, William Hunter, and the Rtv. W. Roberts, were elected Fellows of the Society. The following communications were read : A letter dated September 14 was read, from Lord Derby, sfatin|T that his lordship had received a despatch from her Majesty's Minister ot Tehran, reporting that a mining engineer had arrived there from Berlin, who, at the request of the Persian government, had been selected by Messrs. Siemens to ascertain what founda- tion there was for the reported existence of a rich vein of gold in the vicinity of Zengan ; that he had visited the locality and reported that auriferous quartz does exist, but that he had not yet succeeded in finding any vein or deposit of the metal. — Notes on fossil plants discovered in Grinnell Land by Capt. H. W. Feilden, Naturalist to the English North Polar Expedition, by Prof. Oswald Heer, F.M.G.S. Near Discovery Harbour, where H.M.S. Discovery wintered in 1875-6, in about 81° 45' N. lat, and 64° 45' W. long., a bed of lignite, from twenty-five to thirty feet thick, was found, resting unconformably upon the azoic schists of which Grinnell Land chiefly consists. The lignite was overlain by black shales and sandstones, the former containing many remains of plants ; and above these there were, here and there, beds of fine mud and glacial drift, containing shells of marine mollusca of species now living in the adjacent sea. This glacial marine deposit occurs up to levels of 1,000 feet, indicating a depression and subsequent elevation of the region to at least this extent. Remains of twenty-five species of plants were col- lected by Capt. Feilden, and eighteen of these are known from miocene deposits of the Arctic zone. The deposit is therefore no doubt miocene. It has seventeen species in common with Spitzbergen (78^^ 79' N. lat.), and eight species in common with Greenland (70° 71' N. lat.). With the miocene flora of Europe it has six species in common ; with that of America (Alaska and Canada) four ; with that of Asia (Sachalin) four also. The species found include two species of Equisetuvi, ten Coniferse, Phragmites tvttingt'nsis, Carex noursoakensis, and eight dicoty- ledons, namely, Popiilus arclica, Betula prisca, and Brongniarti, Coryins macquarrii and insignis, Ulmtts borealis. Viburnum nordinskibldi, zxA Nymphcca arctica. Of the Conifers, Torellia rigida, previously known only by a few fragments from Spitz- bergen, is very abundant, and its remains show it to have been allied to the Jurassic genera Phcenicopsis and B cetera, the former in its turn related to the carboniferous Cordaites, and among recent conifers, to Podocarpus. Other conifers are, Thuites ehrensiudrdii^'), Taxodium distichuin viiocenum (with male flowers), Pinus feildetnana (a new species allied to P. strolbus),Pinuspolaris, P^abies[,\.\\\g% covered with leaves), aspecies of Tsuga Pinus dicksoniana, Heer. ), and a white spruce of the group of Pinus grandis and cariocarpa. Pinus abies, which occurs here and in Spitzbergen, did not exist in Europe in miocene times, but had its original home in the extreme north, and thence extended southwards ; it is met with in the Norfolk forest-bed, and in the interglacial lignites of Switzerland. Its present northern limit is 69^° N., and it spreads over 25° of latitude. Taxodium distichuin, on the contrary, spread in miocene times from Central Italy to 82° N. latitude, whilst at present it is confined to a small area. Betula brongniarti, Ett., is the only European species from Grinnell Land not previously known from the arctic zone. The thick lignice bed of Grinnell Land indicates a large peat- moss, probably containing a lake in which the water-lilies grew ; on its muddy shores stood the large reeds and sedges, the birche?, poplars, Taxodia, and Torellue. The drier spots and neighbour- ing chains of hills were probably occupied by the pines and fir?, associated with elms and hazel bushes. A single elytron of a beetle ( Carabttes feiidenianus) is at present the sole evidence of the existence of animals in this forest region. The nature of the flora revealed by Capt. Feilden's discoveries seems to confirm and extend earlier results. It approaches much more closely to that of Spitzbergen than to that of Greenland, as might be ex- pected from the relative positions of the localities ; and the dif- ference is the same in kind as that already indicated by |Prof. Heer between Spitzbergen and Greenland, and would indicate the same kind of climatic difference. Nevertheless, the presence of Taxodium dtstichum excludes arctic conditions, and that of the water-lily indicates the existence of fresh-water, which must have remained open a great part of the year. Representatives of plants no\^ living exclobively in the arctic zone are wanting in the Grinnell Land deposits ; but, on the other hand, most of the genera still extend into that zone, altliough they range in Grin- nell Land from 12° to 15° further north than at present.— On our present knowledge of the invertebrate fauna of the lower carboniferous or calciferous sandstone series of the Edinburgh neighbourhood, especially of that division known as the Wardie Shales, and on the first appearance of certain species in the beds, by Mr. R. Etheridge, jun., F.G.S. Zoological Society, November 20. — Prof. Flower, F.R.S., vice-president, in the chair. — Mr. Howard Saunders exhibited a specimen of the rare Aleutian Tern {Sterna aleutica) from Alaska, and made remarks upon its intermediate position between typical Sterna and the group of the Sooty Terns {Ony- choprion). — A communication was read from the Marquis of Tweeddale, F. R.S., containing an account of a collection of birds made by Mr. A. H. Everett in the Island of Zebu, Philip- pines. Six new species were found in this collection, and were named Oriolus assimilis, Phyllornis flavipennis, Zost crops everetti, PrionocJiilus quadricolor, Turnix nigrescens, and Megapodius pusitlus. — Three communications were read from Dr. O. Finsch, C.M.Z.S. The first contained a report on a collection of birds made at Eua, Friendly Islands, by Mr. F. Hiibner, which had increased our knowledge of the avifauna of Eua from four to twenty-four species. The second contained a description of a collection of birds made on the Island of Ponape, Eastern Caro- linas, by Mr. J. Kubary. The total number of species known at present from Ponape was stated to be twenty-nine, of which seven were peculiar to the island. The third contained a list of the birds obtained at Ninafou Island in the Pacific, by Mr. F. Hiibner. This collection raised the number of the known birds of this island from one to twenty. — Prof. Garrod, F.R.S., read notes on the Taenia of the rhinoceros of the Sunderbunds Plagio' taenia giganted), on the anatomy of the Chinese water-deer {Hydropates inermis), on the possible cause of death in a young seal, and on the occurrence of a gall-bladder in certain species of parrots. — Mr. Howard Saunders, F.Z.S., read a paper on the Laridce collected during the voyage of H.M.S. ChaUinger, which comprised nine species of Sternce, five of Larince, and three of Stercorarincc, altogether seventeen speciej represented by forty- given specimens; sevejalof these were very rare in museums, although none of them were absolutely new to science. — A com- munication was read from Dr. A. B. Meyer, containing some additional proofs of the fact that the Red Eclecti are the females of the green species of that gentis. — A paper was read by Mr. G. French Angas, C.M.Z.S., containing notes on Hdix sepul- charalis of Ferrusac, and its allies, with descriptions of two new species. Physical Society, November 17, — Dr. Stone, vice-president, in the chair. — The president, Prof. G. C. Foster, described and exhibited a very simple form of absolute electrometer, which acts on the same principle as Sir W. Thomson's trapdoor form of apparatus, but can be constructed at a very moderate cost. To one arm of a balance is suspended by silk fibres a zinc disc, which hangs horizontally in the plane of a sheet of the same metal forming a guard-plate ; and at a diitance of about one inch below is a flat sheet of zinc, also horizontal. An electrical connection is formed between the guard-plate and suspended disc by a bridge of very fine wire. The method of using the appa- ratus to determine the potential required for a spark to pass from a Holtz machine through varying thicknesses of air was ex- plained. When the balance has been accurately counterpoised, an excess weight, say one gramme, is introduced into the scale pan, and the guard-plate and the lower attracting-plate, as well as the two knobs of a spark- measurer, are connected with the conductors of the machine. If this be now set in action, and the knobs of the spark-measurer be gradually separated, a point w.U be reached at which the attraction upon the suspended di^c just overcomes the excess weight in the balance pan. The length of spark for which this occurs can now be read off. The dif- ference of potential causing the spark is given by the formula ^ VS/; where a is the radius of the attracted disc, ^ its dis- a ' tance from the attracting-plate, and F the force of attraction in dynes. In the apparatus exhibited, a had the value 5-195 cm., and e the value 24 cm., whence, if w be the excess weight in grammes— so that /^ = 981 w— the difference of potential be- co.nes 39 VaT The proper action of the apparatus depends essentially upon the attracted disc being accurately in the same plane with the guard-plate. To facilitate this adjustment, each of th« silk fibres by which the di?c is suspended is attached to a ii6 NATURE {pec.b, 187;^ £cre V, by which it can be separately raised or laweied ; and by means of another screw the small brass plate holding the sus- pending screws can be raised or lowered as a whole. A few numerical results were given to illustrate the action of the appa- ratus. These were taken from a set of experiments in which the difference of potential needed to produce sparks in air between two equal brass spheres of 2 '61 cm. radius was measured. The following are the results for a; Jew of the shortest and longest sparks measured : — Length of Spark. 0*1325 0-1825 0-237 0-68 0-71 074 Difference of Potential. Mean Electrical Force. 17-4 20-4 24-5 62-9 65-2 68-7 131 117 104 93 92 93 Vienna Imperial Academy of Sciences, October ri. — Preliminary note on the position of the optical axes of elasticity in gypsum for various colours, by M. Lang, The angle of the optic axes shows a maximum for the Fraunhofer line D. The dispersion of the axes of elasticity in the plane of symmetry is abnormal. These observations agree on the one hand with Poggendorfif' s exact description of the axial forms of gypsum, and on the other side with Descloigeaux's observation that at the higher temperatures, where the plane of axis is at right- angles to the place of symmetry, no horizontal dispersion is observable. — Annual periods of the insect fauna of Austro- Hungary, by M. Fritsch. — On the relation between the second principal proposition of the mechanical theory of heat and the calculation of probability respecting the propositions on heat- equilibrium, by M. Boltzn.ann. — The cylindroid and its spe- cialties, by M. Kozak.— Simple calculation of elliptic arches, by G. Seewald. — On eruptive sands, and on the Flysch and the Argille scagliose, by M. Fuchs. — On equal figures in curves, cones, and surfaces of the second order and of certain of higher orders, by M. Puchta. — Calculation of cylindrical vessels with complicated relations, by M. Streicher. — On development of the resinous passages in some coniferge, by M. Weiss. — Continued studies on the mode of ending of nerves of smell, by M. Exnor. Paris Academy of Sciences, November 26.— M. Peligot in the chair : — The following papers were read : — Geographical posi- tions of the principal points of the coast of Tunis and Tripoli, by M, Mouchez. This relates to observations during the hydro- graphic voyage of the Castor in 1876, of some fifty points equally distributed along about 300 leagues of coast. — On some applica- tions of elliptic functions (continued), by M. Hermite. — The Echidna of New Guinea, by M. Gervais. He notes several points in which the head differs, from that of the Australian animal. — On invariants, by Prof. Sylvester. — On the waves of various kinds which result from the working of the sluice of Aubois, by M, Caligny. — On the solution of the equauon of the fifth degree, by M. Brioschi. — Nature of the hydrocarbons pro- duced by action of acids on manganesiferous spiegeleisen, by M. Cloez. Several of these products seem identical with those which exist in the ground and are extracted on a large scale under the name of petroleum. This production of complex carbonised compounds, without any intervention of life, supports the views of certain geologists on the origin of petroleum. The reproduc- tion of a large number of organic species might be realised tiy com- mencing with ethylenic or formenic hydrocarbons, furnished by cast iron. — Discovery and observation of the planet 175 by Mr. Watson. — On the distances of stars, by M. Flammarion. He cites several facts which seem not to allow of basing on differ- ences of brightness an estimate of dit^tances. — On the interme- diary integral of the third order of the equation with partial derivatives of the fourth order expressing that the problem of geodesic lines supposes an algebraic integral of the fourta degree by M. Levy. — Graphic tables and anamorphic geometry j recla- mation of priority, by M. Lalanne. — Second note on the mag- netisation of steel tubes, by M. Gaugain. The variations of magnetism produced by heat in a solid bar of steel ar« not different icova. those in a system composed of a tube and a core. Both seem to depend on the inverse magnetism developed by the mutual reaction of concentric layers, whether of the bar or of the system. — Liquefaction of bioxide of nitrogen, by M. Cailletet. This he effected by compressing to 104 atmospheres at — 11°. At + 8° the bioxide is still gaseous under 270 atmospheres. He hopes, also, to be able to liquefy formene. M. Berthelot remarked on the importance of this achieve- ment, and thought it probable that most of the gases not yet liquefied, such as oxygen, which already diverges from Mariotte's law under great pressures, and oxide of carbon, would yield to M.'Cailletet's new processes. — On nitrification by organic ferments, by MM. Schloesing and Muntz. Whenever, in these experiments, a nitrifiable medium has remained in the presence of chloroform, or has been heated to 100°, then guarded from dust, the nitrification has been suspended, but it has been possible to renew it, by introducing into the heated medium a minimum quantity of a substance like mould in process of nitrifi- cation.— On the termination of the nerves in tactile corpuscles, by M. Ranvier. He studied these organs in the tongue and bill of the domestic duck (where they are found in great simplicity). The tactile disc, the true sensitive nervous organ, is protected against mechanical excitations from without by the special cells surrounding it. It can only be impressed in an indirect way. — An experiment in stasimetry or measurement of the consistence of organs, by M. Bitot. The instrument is a kind of balance having at the end of one arm a perforating or sounding needle, at the end of the other a small controlling plate, and at the centre a pendulum with successive weights and a long indicator needle connected to it above, moving over a graduated scale. — On a mo- dification of Bell's telephone, with multiple membranes, by M. Trouve. A cubical chamber is substituted for the single mem- brane ; each face of it is a membrane which, in vibrating, influences a fixed magnet with electric circuit. Associating all the currents generated, an intensity is obtained proportional to the number of magnets affected; — On the telephone, by M. Pollard. This describes some experiments at Cherbourg. M. Du Moncel called attention to the ideas expressed by M. Ch. B more than twenty years ago, and which contains the telephone in germ. — On a new sounding apparatus for works of coast hydro- graphy, by M. Pinheiro. CONTENTS Page Technical Education 97 North American Starfishes 9^ Vogel's "Spectrum Analysis." By Dr. Arthur Schuster . . 99 Our Book Shelf :— Young's "Nyassa; a Journal of Adventures whilst Exploring Lake Nyassa, Central Africa, and Establishing the Settlement of ' Livingstonia ' " 99 Cayzer's "Britannia: a Collection of the Principal Passages in Latin Authors that refer to this Island " 99 Letters to the Editor : — The Colour Sense of the Greeks.— ReV. W. Robertson Smith . iod Ihe Comparative Richness of Faunisand Floras tested Numeri- cally.— Alfrbd R. Wallace ico Mr. Crookes and Eva Fay.— Alfred R Wallace 101 Nocturnal Increase of Temperature with Elevation. —Dr. E. Bonavia 10 ' Expected High Tides —B. G. Jenkins loi Diffusion Figures in Liquids —C Tom LiNSON, F.R S 102 Bees and Flowers — John B. Bridgman 102 Hearing in Insects. —Henry Cecil 102 A Zoological Station for the Channel Islands. By W. Saville Kent i°3 German Universities 1^3 Our Astronomical Column : — The Meteorite of July 20, i860 104 The Planet Mars and B. A. C. 8129 loS The Binary star Ca^tor 105 Transits of the Shadow of Titan across the Disc of Saturn . . . 105 The " Nautical Almanac," i83i 103 Ole RoMER. By Dt.'^. DoBKKQK. (With Illustrations) .... 105 Notes '^°^ The Liberty of Science in the Modern State, IIL By Prof. Rudolf Virchow ^'^ American Science "3 The Meteor "3 University AND Educational Intelligenck "4 SOCIKTIKS AND AcADBMIBS . .1 , .... "5 NA TURE t'7 THURSDAY, DECEMBER 13, 1877 HYDROPHOBIA POPULAR alarm has of late been aroused by the publication of an unusual number of cases of death from this most terrible disease, and interest and hope have been excited by the statement that, at last, a drug has been found — curare — which does exert such an influence that at least one case is said to have been rescued from otherwise certain death. We propose to discuss briefly in this article the chief points in the natural history of hydrophobia, to examine what light, if any, science has thrown upon its nature, and to inquire what reasons there are for believing in the alleged efficacy of drugs in its treatment. Hydrophobia is a disease which never occurs spon- taneously in man, being invariably communicated to him by the bite of some animal affected with it — commonly by the dog, more rarely the cat, more rarely still the fox and wolf. The bite induces the disease by permitting the absorption of the saliva of the diseased animal, the peculiar poison or '^ inateries tnorbi" of the disease being con- tained in the saliva. Inasmuch, then, as man only becomes affected with hydrophobia through the inter- mediation of the lower animals, it will be necessary to consider it, first of all, as it makes itself manifest in them. It has been, and still is, a subject of dispute amongst veterinarians whether hydrophobia, or " rabies," was origi- nated spontaneously in the dog. Avowedly the immense majority of cases of the disease can be proved to have been due to the bites of rabid animals; some cases do occur, however, in which it is stated that there was no possibility of contact with a diseased animal, and these are held to prove the occasional spontaneous origin of the disease. Now, whilst we are not prepared absolutely to contradict such a surmise, and to allege that at no time, and under no circumstances, hydrophobia originated spontaneously, we do hold that there is no better evidence of such a new origin now than there is of the spontaneous generation of the poisons which induce small-pox, scarlet fever, or measles. In the case of these diseases, as in that of hydrophobia, it does sometimes happen that some of the links in the chain of evidence are lost which are required to prove the connection between one case of disease and its precursor, but the exceptional cases do not outweigh the immense mass of evidence which proves that each of the diseases previously mentioned is as certainly the offspring of a previous case as is each animal or plant at present living the offspring of a pre- existing parent organism. We shall then probably be quite right in assuming that not only is it true of hydro- phobia as it affects man, but of the disease as it is manifest in all animals, that it is always due to the inoculation of poison from a diseased into a healthy organism. In commencing a description of hydrophobia we must point out that whilst the disease is always more or less prevalent, periods when it becomes much more frequent occur from time to time. Within the present century, especially between 1800 and 1830, several such outbreaks occurred ; in this respect hydrophobia resembles other Vou XVII,— No, 424 diseases of the zymotic cla«s, which, though always more or less prevalent, only occasionally prevail with epidemic intensity. We must assume that at this period the cir- cumstances which are required for the spread of the par- ticular disease are specially favourable, though it is only rarely that we can do more than surmise what these special circumstances really are. In the dog, as indeed in all animals, there is a period of latency, or as it is technically termed, of " incubation," which intervenes between the inoculation of the poison of hydrophobia and the development of any symptoms ; this period varies remarkably : it may be as short as a week, or as long as three months ; the greater number of cases occurring, however, between the twentieth and fiftieth days after the poisonous wound has been inflicted. It must not be supposed that the bite of a rabid dog always induces the disease in other dogs which it bites ; a certain number of such bites prove abortive. Thus, out of 131 dogs which had been bitten by, or inoculated with, the virulent saliva of certainly rabid dogs, only sixty- three fell victims. The failures in these cases are to be explained in several ways. In some cases it is probable that the saliva was not active, just as sometimes the liquid from the vaccine vesicle, when fairly tested, is found to be incapable of reproducing vaccinia ; in other cases the poisonous saliva has doubtless been prevented from penetrating the wound, having been retained by the hair and cuticle of the bitten animal ; finally, in a third class of cases, it must be assumed that the bitten animal did not offer conditions required for the development of the disease. A case is, indeed, recorded, on the best authority, in which a pointer dog was caused to be bitten on seventeen separate occasions by dogs affected with rabies, without the disease being induced. The period of incubation having passed, the fii*st symptoms of rabies usually consist in a change in the temper of the dog, which becomes sullen and snappish, and which often bites those around it, even without any provocation. This prominence of the cerebral symptoms in the early stages of hydrophobia in the dog is very remarkable, and contrasts, as will be seen in the sequel, with the phenomena of the disease in man. It is evidenced not merely by the tendency to bile, but by the whole changed aspect of the animal, which is now observed to be obviously ailing. The appetite becomes capricious, food often being refused, and all kinds of rubbish swallowed, and often, though ^by no means invariably, the dog utters dismal howls. It is in this stage that the dog often wanders from home, and ap« parently under the influence of maniacal excitement, rushes on, biting all dogs which it meets, and often all human beings who happen to come in its way. It is to be noted that the dog does not exhibit any of the dread of water which is so painfully evident in the disease as it affects man ; this depends upon the fact that in the dog there appears to be little, if any, tendency to spasm of the muscles of deglutition. As the disease advances palsy of the posterior extremities often occurs ; in other cases a peculiar paralysis of the muscles connected with the lower jaw sets in, so that the suffering animal ii unable to utter any sound, and is said to be suffering from " dumb-madness." Throughout the disease there is usually an increased secretion of viscid saliva. The ii8 NATURE {Dec. iz, 1877 whole course of hydrophobia in the dog is run in from four to eight days, the majority of cases proving fatal about the fourth or fifth day. This short description of rabies or hydrophobia, as it affects the dog, is almost exactly applicable to the disease as it occurs in other domestic animals ; a maniacal excitement and a tendency to injure men and animals with which they come in con- tact being as characteristic of herbivorous animals as it is of dogs, cats, foxes, and wolves. Having, then, before us an outline of hydrophobia as it affects the lower animals, let us compare with it the disease as it is observed in man. In the first place as to the frequency with which the bite of a mad dog is followed by hydrophobia. No general satement can be made on this matter, as the results vary very greatly according to the part bitten, according to the treatment to which the bitten part is subjected, &c. For instance, bites inflicted upon parts protected by clothing are followed by hydrophobia much less frequently than those in which the hand or face is injured, the poison in the former case being absorbed by the intervening clothing. Next, as to the period of incubation. In man this varies even more thaia in the case of the dog ; the majority of cases of human hydrophobia have, however, a period of incubation which varies between thirty and fifty days, though exceptional cases occur in which many months have elapsed between the infliction of the bite and the supervention of the symptoms ; these remarks might be illustrated by reference to cases which have occurred in England, and which have been recorded in the medical journals during the last two years ; the shortest period of incubation observed within this period having been eighteen days, and the longest nine months. During the period of incubation there is nothing to distinguish a bite inflicted by a rabid dog from the bite of a healthy dog. The study of some of the recorded cases of the disease would almost lead to the conclusion that in man there is during the period of incubation a tendency to nervous depression and melancholia which is a precursor of the terrible symptoms which are to follow ; it is obvious, however, that great caution ought to be exercised in the interpretation of such mental symptoms, which are after all in many cases but the necessary and logical results of an injury of which the possible consequences are but too well known and correspondingly dreaded. If we except these symptoms of depression and melancholy there are no characteristic phenomena which intervene between the infliction of the bite and the onset of the attack of hydrophobia. In a certain number of cases the advent of the disease is ushered in by pain of a neuralgic character in the bitten part ; this appears to be merely an evidence of the general feeling of illness which then supervenes, rather than any evidence of the specific nature of the bite. More commonly the first phenomena are merely vague symptoms of feeling very unwell, accompanied often by an intense feeling of melancholy. A deep sighing cha- racter of the inspirations, or even paroxysmal attacks of difficulties of breathing, wiih some pain in the throat and pain in the precordial region often follow. Beyond the feeling of impending evil, there is no "mental symp- tom at this stage of the disease at all comparable with those observed in the lower animals. Next in the order of accession is the difficulty which the poor patient experiences in swallowing ; this, at first slight, symptor.i soon acquires a terrible intensity ; the patient is troubled by an agonising thirst, and yet dares not drink ; an} attempt to drink gives rise to a terrible spasm of the muscles engaged in deglutition, and apparently to a simultaneous spasm of the muscles engaged in inspiration so powerful that he dreads suffocation. An analysis of the symptoms at this stage leads one, indeed, to the opinion that swallowing is often dreaded because of, and is indeed impeded by, the spasm of the inspiratory muscles which it induces. Then follows a stage in which" often, though by no means invariably, the patient becomer subject to delusions, and often violently maniacal, and this is succeeded by a stage of exhaustion and quiet which ushers in the fatal termination. If we have sketched with some degree of minuteness the outlines of a very painful picture, we have done so because a knowledge of them was absolutely essential before we could 'attempt to consider what light science has thrown upon this dread disease, and what reliance is to be placed upon the remedies which have been suggested for its cure. We shall now, in the first place, consider the results of pathological investigations relating to hydrophobia. Are there not some well marked and constantly present lesions of the great nerve-centres corresponding in some measure to the symptoms which manifest themselves during life t The older observations generally concur in showing that the brain and spinal cord are the seat of congestions which are,however, not sufficiently constant in their localisation to admit of any conclusions being drawn from them. And, since the time when pathological anatomy attained its present development and accuracy, but few persons sufficiently competent to draw accurate conclusions from their observations have had the oppor- tunity of working at the subject. From the observations of Benedict (F^Vr/^ija/'^ Archiv, 1875), it resulted, that in addi- tion to more or less widely spread congestion, there occur granular degeneration of nerve-cells, and of nerve-fibres in various parts of the brain. Subsequently Wassilieff, working under the direction of Prof. Botkin, of St. Peters- burg, described {Centralblait f. d. ined. Wissenschnft, 1876, p. 625) a, some alterations in the nerve-cells of the medulla oblongata, the outlines and nuclei of which are indistinct and the contents cloudy ; /5, a large accu- mulation of corpuscles of the size of white blood-cells in the interstitial connective tissue of the brain, in the peri-vascular canals and immediately surrounding them ; and ^, the presence of a highly refracting substance in the peri-vascular spaces, especially in the cortical layers of the cerebral hemispheres. Somewhat akin to them are the observations of Dr. Gowers who found in the medulla oblongata after death from hydrophobia, accumulations of cells, resembling white blood-cells, in the vicinity of the blood-vessels, and [also in the nervous substance. But what do all these observations indicate ? In all probability the accumulations of white cells are caused by the emigration of white blood corpuscles from the blood, so that they are to be held as supporting the older observations which alleged congestions of the brain to be frequently present, and the other pathological changes Dec. 13, 1S77] NATURE 119 noticed by the three observers to whom we have referred, cannot as yet be adequately interpreted. Pathological anatomy then helps U3 a little in our tempts to elucidate hydrophobia. Can we obtain better iciults by reasoning upon the symptoms and course of the disease from the standpoint of physiology ? Hardly, but we may nuke the attempt. Physiology necessarily cannot help us to understand the nature of the peculiarly subtle poison which can lurk so long in the system with- out betraying its presence by any symptom, but she may help us in explaining the phenomena which it in- duces. Of this poison we know as little, if not less, than of the other poisons which are capable of inducing zymotic diseases. Each of those diseases appears to depend upon a definite luateries tnorbi, upon the presence of whi h the peculiar phenomena of each dept-nd ; but the periods which elapse between the introduction of the poison and the manifestation of the disease varies in each case, no less than the course and duration of the disease, and the organs and tissues of the body whicli are affected. Thus, in scarlet fever the poison induces changes in the epitheliated surfaces of the body, manifested by the rash, the sore throat, the acute kidney affection ; in typhoid fever anatomical changes of the most obvious nature are wrought in the alimentary canal, and lead to the special dangers of the disease ; in typhus, again, the poison, whilst producing changes in the general nutritioa of the body, and exciting a specially-marked action upon the brain proper (as evidenced by the marked affection of all mental pro- cesses), produces no typical anatomical changes. These diseases all illustrate the fact that the poison of each zymotic disease affects certain tissues and organs of the body, and it might be easily shown that it is by the implication of particular functions that each of these poisons usually induces death. Is there, in the case of hydrophobia, any evidence that it affects specially any particular organ of the body ? Yes ; a physiological analysis of the disease reveals the fact that its symptoms depend upon an affection of the nerve-centres, and espe- cially of the medulla oblongata. These essential symptoms are — the spasmodic difficulty of breathing, which depends upon a spasm of the inspira- tory mechanism and a spasmodic affection of the group of muscles engaged in deglutition. The nerve-centres which preside over respiration and the co-ordinated movements of deglutition are situated in the medulla oblongata, and it is these centres which appear to be peculiarly affected. The reflex excitability of this portion of the nervous apparatus becomes first of all heightened so that a stimulus applied to the mucous membrane of the gullet, which in health v/ould give rise to a normal con- traction of the muscles of deglutition, travelling on to the morbidly irritable medulla, throws the centre presiding over deglutition into a state of tonic spasm so intense as to be acutely painful ; not confining its action to this one centre, the stimulus is able to throw the contiguous respiratory centre into a similar state of spasm, and the patient runs the risk of suffocation because the move- ments of the thoracic box, which are essential causes of the passage of air into and out of the lungs, cease for a time. The mechanism of suffocation in these cases resembles that observed when the upper end of the pneumogastric nerve is stimulated by a succession of strong induction shocks, except that in hydrophobia the abnormal effect is doubtless due not to the intensity of the stimulus, but rather to the heightened excitability of the nerve-centres implicated. Apparently a subtle animal- poison acting upon an intensely vulnerable but limited part of the nervous mechanism induces in it an action Fimilar in kind to that produced by strychnia upon the. spinal cord. Under the influence of this well-known poison the excita- bility of the nerve-centres in the cord is heightened, so that a stimulus reaching it by an afferent nerve which would in the healthy unpoisoned condi ion lead to the reflex and painless contraction of but a small group of rnuscles, will be able to throw the nerve-cells of the whole cord into intense activity, and as a re^^ult occasion the characteristic and terribly painful convulsions of strych- nia poisoning. There are, indeed, other facts besides those previously mentioned which point to a state of irri- tation and increased nervous excitability of the medulla and contiguous nerve-centres. Thus it has been observed that occasionally the pulse has been abnormally slow, a result almost certainly due in these cases to an excitation of the inhibitory centre in the medulla — of that centre which exerts a moderating or restraining influence upon the heart's action ; further, it not unfrequently happens that towards the close of the hydrophobic stage, stimuli which were at first only capable of inducing the spasms of deglutition and inspiration, are able to bring on attacks of general convulsions. Here we have a still further extension of the effects of the irritation due to an extension of the reflex excitability from the medulla to the spinal cord. x Our analysis of the symptoms of hydrophobia reveals that as a rule the spasmodic stage terminates before death, which is not produced, as in strychnia poisoning, by the mechanical result of the convulsions — suffocation — but apparently by a more general, though we confess unknown, action of the poison on the organism generally. We know as little of the mode of death in this case as we do in that of scarlet fever, or diphtheria, or typhus, each one of which may produce death without leading to the anatomical results which, at any rate in the case of the two former of these diseases are their usual accompani- ments. Zymotic poisons may indeed leave as few traces of their action as the simpler and belter known poisons such as prussic acid or morphia, so that whilst we cannot disregard the local manifestations or changes which they induce, and which of themselves are a frequent source of danger, we must admit that they are in many cases — nay in most cases — secondary in importance to the more general phenomena which are the expression of the poisonous influence affecting the. organism. {7^ be co?t(inUid,) ANCIENT HISTORY FROM THE MONUMENTS Ancient History from the Monuments. The History of Babylonia. By the late George Smith ; edited by A. H. Sayce. The Greek Cities and Islands of Asia Minor. By W. S. W. Vaux. (Society for Promoting Christian Knowledge, 1877.) THE Society for Promoting Christian Knowledge has been doing a very useful work in acquainting the public with the historical results of recent Oriental research 120 NATURE [Dec. 13, 1877 in a cheap and handy shape. The work has been wisely placed in the hands of those who have themselves been pioneers in the task of discovery, and the reader has thus been secured against the errors and unfounded conclu- sions almost inseparable from second-hand informa- tion. The histories of Egypt, Assyria, and Persia, have now been followed up by those of Babylonia and Asia Minor, and the fact that the history of Babylonia was the last literary work which Mr. George Smith, the indefati- gable Assyrian explorer, lived to accomplish, gives a melancholy interest to it over and above that of its sub- ject matter. Indeed, the materials for reconstructing Babylonian history are still but scanty, and must remain so until systematic excavations can be made among the buried cities and libraries of anc ient Chaldea. With the exception of a few early bricks and a fev/ dedicatory inscriptions of Nebuchadnezzar and his successors, it is from the clay tablets of Nineveh that almost all our knowledge of the sister kingdom has been derived. Even Babylonian chronology is still in an uncertain and tenta- tive condition, and the fragments of the Babylonian his- torian, Berosus, help us but little. Whole periods must still be left blank, and though one or two dates, like the conquest of the Elamite king, Cudur-nankhundi, in B c. 2280, can be fixed by the aid of later monuments, the relative position of even whole dynasties has not yet been settled. Our acquaintance with the mythical epoch is quite as great as with the historical epoch ; the Assyrians preferred the legends of the rival monarchy to a record of its glories, and while, therefore, we now have in detail the stories of the creation, of the flood, or of the hero Izdubar, we know comparatively little of the political changes which passed over the Babylonia of history. Compared, however, with what we knew of them a few years back, even this limited knowledge seems large and accurate, and the best evidence of this is the volume which Mr. Smith has written, and which would have been an impossibility but a short time ago. Those who wish to learn what light has been thrown by cuneiform disco- very on this important section of ancient history cannot do better than refer to his book. The importance of Babylonia for the history of culture and civihsation is daily becoming more manifest ; the early Accadian popu- lation of ihe country, who spoke an agglutinative lan- guage and invented wriiing, left a r ch inheritance of art, science, mythology, and religious ideas to their Semitic successors, and throug!i them to the Jews and Greeks. The latter were influenced partly through the Pnoenicians, partly through the nations of Asia Minor. Mr. Vaux's volume on the Greek cities of Asia Minor is therelore a suitable companion to Mr, Smith's " History of Babylo- nia." His difficulty in compihng it must have been the converse of Mr. Smith's, as here it was not the meagre- ness but the superabundance of materials which was likely to cause embarrassment. His selection, however, is good and judicious, and the book he has produced is at once instructive and readable. He has not forgotten to invoke the assistance of the latest discoveries ; the first few pages are devoted to an account of Dr. Schlie- mann's life and discoveries, and the researches of New- ton, Wood, and Fellows, have been largely drawn upon. Considering the space at his command, Mr. Vaux must be congratulated upon the amount he has been able to cram into it, and, so far as we can see, no city or fact of importance has been omitted. Both volumes are appro- priately illustrated, and the " History of Babylonia " con- tains a copy of a bronze image of an ancient Chaldean monarch recently brought to the British Museum, and interesting on account of the rarity of such early monu- ments. Their value is further increased by the addition of indices, and the editor of Mr. Smith's volume has added a chronological table of the Babylonian kings, and an explanatory list of proper names. FRENCH POPULAR SCIENCE Musee Entomologiqice IllustrL Les Papillons : Organisa- tion, Chasse, Classification. 80 Plates and 260 Wood- cuts. Les Coleoptires : Organisation, Moeurs, Chasse, Collections, Classification. 48 Plates and 335 Woodcuts. Anatofnie et Physiologie de VAbeille. Par Michael Girdwoyn. 12 Lithographic Plates. Les Champignons. Par F. S. Cordier. 60 Chromolitho- graphs and 8 Woodcuts. Les Prai7-ies Artificielles. Par Ed. Viaune. 127 Woodcuts. Les Ravageurs des Fortts et des Arbres d'Alignement, Par H. De la Blanch^re. 162 Woodcuts. Les Ravageurs des Vergers et des Vignesj avec lUiC J^tudc sur le Phylloxera. Par H. De la Blanch^re. 160 Woodcuts. Le Chaluineau. Analyses Qualitatives et Quantitaiivcs. Guide Pratique. Traduction libre du Traitd de B. Kerl. Par E. Jannettaz. Les Aliments. Determination Pratique de leurs Falsifi- cations. Par A. Vogl. Traduction par Ad. Focillon. 160 Woodcuts. V (AH published by J. Rothschild, Rue des Saints- Peres, Paris.) WE have received the preceding balch of works from the house of Rothschild of Paris. This is not the first time we have been able to show not only how worthily M. Rothschild is maintaining his position as one of the first publishers of popular science works of the time, but how eagerly such works are read, and how highly they are appreciated in France. It is impossible to speak too highly of the honest work which has been put into each of the volumes, while many of them are written by men whose names are widely known on this side the Channel. As is proper in this style of literature, the text is equalled by the illustra- tions. Why is it that in the matter of illustrated books such as those before us, the French finished product is so far superior to nine-tenths of those published on this side the water? Nothing can exceed the perfection of many of the hundreds of woodcuts in the above volumes, while we have rarely seen more finished specimens of chromolithography than those to be found in some of the volumes. We cannot think that the French public is so far beyond our own in its appreciation of science, as to make the publication of similar works in our own coantry hopeless. We shall therefore give an analysis of each of the above works in a single article, with a view of showing the treatment adopted abroad in popularising the branches of science with which the volumes deal, 'nstead of devoting Dec. 13, 1877] NATURE 121 one to each of them in turn, which we should have been quite justified in doing, having regard to their value. Of the two volumes on the Natural History of Insects, which are published by a society of French and foreign entomologists, vol. i. is devoted to the Coleoptera, and comprises their organisation and their different orders, with a short description of each, and woodcuts showing their different stages of development. These are fol- lowed by other useful matter, and then, in the second part, we come to " Le Monde des Scarabdes." The stag- beetle is here taken as an example of his family to show the anatomy of these insects. The description of their dwellings and instincts is clear, and written in such a style that it may be understood and enjoyed by those not versed in entomology. This part occupies a good portion of the book. In the pages devoted to the hunting, preparing, and keeping of beetles, beginners may find every information they require; pincers, pins, and nets are all shown, as well as the necessary requisites for the knapsack. A list of the principal entomological works is given, after which we have a lengthy classi- fication and iconography of European coleoptera, illus- trated with forty- eight plates beautifully coloured by hand. The arrangement of volume ii., on Butterflies, is very similar to the above, and contains thirty coloured plates illustrating the butterfly, caterpillar, and chrysalis, to- gether with the plants on which these are most frequently to be found. " The Anatomy and Physiology of the Bee," is taken from volume vi. of the " Memorials of the Polish Society of Exact Sciences in Paris," and translated into French by M. Pillain. This work consists of twelve lithographic plates which obtained medals of merit both at the Univer- sal Exhibition at Vienna and from the Royal and Imperial Society of Agriculture of Cracow. On these plates we have 172 figures of the various parts of a bee, greatly magni- fied. It is scarcely necessary to add that these are extremely well finished. In the folio we have the memoir itself, a book of forty pages, which first introduces us to the bees of different countries and the bibliography of the subject. In chapter i, the author describes the exterior parts of the bee, and in the second and third the interior and more complicated, such as the muscles, nervous system, circulation of the blood, &c. The work terminates with explanations of the figures. Altogether this is a valuable addition to an entomologist's library, and does great credit to the society from which it has emanated. In M. Cordier's book on Fungi we have much valuable information. In the first place he treats generally of the organisation of fungi, their physiology, mode of reproduc- tion, and geography, how to distinguish the edible from the poisonous, and he shows us how to extract this poison ; he tells how this works on the animal economy and the best means of counteracting it. In the second part all the fungi useful to man are chronicled, with detailed descriptions of each order and drawings from nature. M. Cordier has adopted Persoon's classification in preference to any other, as he takes it to be more practical ; indeed he dedicates the book to his memory as the " Crdateur de la Science Mycologique." The drawing and colours of the sixty chromolithographs are well worthy of note. The book also contains a glossary, table of common, and one of the scientific, names of the fungi. The author has evidently endeavoured to make his subject as interesting and complete as possible. The style of the popular portion of the book is admirable, and bon vivants will be glad to be informed that there are eight pages dealing with the proper way of cooking truffles. The two small books by H. de la Blanch^re — one on the enemies of forest trees, with 162 engravings of insects and larvae, the other on the enemies of orchards and vines similarly illustrated, form part of a large series now well known and highly appreciated in France, We have already noticed some of them, and these are in no way inferior to the former ones. " Plants used for Food," written by A. Vogl, of Prague, translated into French by Ad. Focillon, is a practical guide for detecting the adulteration of flour, coffee, chocolate, tea, and the like. " The Blowpipe," by E. Jannettaz, is extremely well arranged, and is a thoroughly practical guide for engi- neers, mineralogists, ^c. ; the information is accurate and condensed, and M. Jannettaz's name is a guarantee of its scientific value. OUR BOOK SHELF The Fifth Coniine7it, with the Adjacent Islands ; being an Account of Australia, Tasmania, and New Guinea, with Statistical Itiforviation up to the Latest Date. By C. H, Eden. With Map. (London ; Society for Promoting Christian Knowledge ; no date.) This volume contains much information on the Aus- tralian colonies, but it is somewhat desultory and in- complete. It is not a children's book, and it will not satisfy those who are in quest of full information on the subject It affords some idea of the history, people, and products of Australia and New Guinea, but it would be better to cut out much of what is said about the history and the people and give more space to well-digested information about the resources of the countries. Notes by a Field Naturalist in the Western Tropics. By Henry H. Higgins, M.A. (Liverpool : Edward Howell, 1877.) This is a readabla record of observations made during a yacht voyage to the West Indies by Mr. Higgins, who is president of the Liverpool Naturalists' Field Club. Mr, Higgins went over well-trodden ground, and therefore we need not look for any novslties in this little volume, although much of it is interesting. The chief purpose of the voyage, undertaken by Mr. Cholmondley, the owner of the yacht, was to observe and collect tropical birds. Mr. Higgins collected, also, many specimens, both zoological and botanical, from sea and land, which are now being arranged. He may possibly, he states, publish an account of the biology of the voyage. LETTERS TO THE EDITOR \The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts. No notice is taken of anonymous communuations. The EdUor urgently requests correspondents to keep their letters as short as possible . The pressure on his space is so great that it is impossible otherwise to ensure the appararue even of cam' munications containing interesting and novel facts. \ The Radiometer and its Lessons Prof. Foster's dear representation of what he conceives to be the effect of rarefaction reduces the question between us to a definite issue. Having assumed that heat is flowing across an intervening layer of gas from a hotter surface A to a colder turfice B, h« 122 NATURE [Dec, 13, 1877 sjQfs : — "Then, I imagine, the flow of heat through the gas will take place as though there were, in contact with each solid surface, a layer of gas whose temperature is throughout the same as thai of the contijiuous solid, and whose thickness is equal (or at least proportional) to the mean length of path of the molecules." Without these layers of uniform temperature or whatever may produce an equivalent effect it follows directly from Pi of. Foster's reasoning that the rate at which heat is communicated is, as I maintain it is, independent of the density, whereas if there were any such layers I should at once admit the force of Prof. Foster's reasoning. The who'e questiiar turns therefore on the existence of ihese layers of uniform temperature. Now what evidence of such layers have we ? No experimental evidence certainly ; and not only has the kinetic theory not as yet been appled to expla-n their ex'stence but it is easy to demonstrate that according to this theory no such layers or any equivaleiit can exist. For in order that the condition of heat may remain unaltered it is necessary that the rate at which heat is transmitted across all suraces parallel to the solid surfaces which can be drawn through the gas should be the same. And the rate at which heat is transmitted is for small variations of temperature propnnional to the degradaii'm of tempe'ature, hence if there were a layer of unilorm temperature no heat could be transmitted. It is surely incumbent on Prof. Foster in assuming the existence of thtse layers to give some sort of proof in support of his assumption, but not one word does he say ! I cannot allow this to pass without pointing out that the description which Mr. Stoney has given of my viev/ is grossly wrong and is certainly not to be gathered from anything I have written. Mr. Stoney carefully turns my position. He makes out that I have explained the action in question as arising from convtction currents, whereas I have from first to last maintained that it is these currents which oppose and eventually overcome the action. He makes out that my theory takes no account of molecular motion, whereas, in truth, it takes no account of any- thing but molecular motion, the effect of the expansion of the gas being so obviously trivial that I have never even men- tioned it. Your readers may judge of this by comparing the first of the following quotations, which is from Mr. Stoney's letter, with the others which are from my own papers, and are the only expres- sions, not mathematical, which I have given of my views as to fiction in the question : — Mr. Stoney's. "Prof. Osborne Reynolds's explanation is based on the fact that when a disc with vertical sides is heated on one side and exposed to a gas, a convection current sets in, which draws a continuous supply of cold gas into contact with the hot surface of the disc. As this cold gas reaches the disc it is expanded, and thus its centre of gravity is thrown further from the disc. Accordingly, the disc, if freely suspended, will move in the opposite direction so as to keep the centre of gravity of the gas and disc in the same vertical line as before, and, if not freely suspended, will suffer a pressure tending to make it move in that direction. If I have understood Prof. Reynolds aright, this is both a correct and full descrip- tion of his explanation as last piesented." My Own. " Whenever heat is commu- nicated from a hot surface to gas, the particles which im- pinge on the surface will re- bound with a greater velocity than that with which they ap- propriate ; and consequently the effect of the blow must be greater than it would have been had the surface been of the same temperature as the gas. " And, in the same way, whenever heat is communicated from a gas to a surface, the force on the surface will be less than it otherwise would be, for the particles will re- bound with a less velocity than that at which they approach.' " These forces arise from the communication of heat to or from the surface from or to the gas. These forces will be directly proportional to the rate at which the heat is communi- cated ; and since this rate has been shown by Prof. Maxwell to be independent of the den- sity of the gas, these forces will be independent of the density of the surrounding medium, and their effect will increase as the density and convection- currents diminish." ^ Proceedings, Royal Society, 1874, p. 407. Pkil. i)/(?^., November, 1874, p. 3. The first of the quotations from my papers is followed by a mathematical expression on which I have depended for com- pleteness, and from thi-i expression, in which neither convection currents nor the expansion of the g*s have any place whatsoever, it follows that whenever heat is steadily diffusing into or through a gas, the momentum transmitted across any surface in the direction in which the heat is diffusing will be greater than that transmitted in the opposite direction by a quantity proportional to the rate at which the heat diffuses, divided by the square root of the absolute Temperature of the gas. As to the value of what follows in Mr. Stoney's letter, I must leave it to your readers to decide. He proceeds to claim that his own theory has the advantage of being based on molecular mot'on«, he says : — *' My explanation, on the other hand, is based on molecular motions which go on in the gas without causing any molar mo'ion, and is independent of convection currents." Then having thus attributed to me an explanation, I never even thought of offering, and having assumed the true base of my theory as alone belonging to Ins. he proceeds to show wherein I am wrong. And ia every subsequent position which he attributes to me, he is as wrong as he is in h's first statement. Under these circumstances it would be useless for me to enter upon questions a>. to how far "diffusion," ace irdmg to the kinetic theory may be moie "sluggish " than Mr. Stoney's " penetration, ' or to discuss lurther the possibility of his " Crookes's layers." In my last letter I showed that the condition of a gas which Mr. Stoney called a " Crookes's layer" was impossible, and I do not see that Mr. Stoney has improved his position by showing that he had arrived at the \ ossibility of the condition by making the false assumption '^ that gas is a perfect non-conductor of heat.'" Wherein Mr. Stoney's views are at variance with the results of the laborious investigations of Maxwell, Clausius, Tiiomson, and others, he may best convince himself by referring to the works of the.'C authors. Until he has read my papers and explained the discrepancies between his views and the generally- accepted laws of gase-, I do not see that we have any common grrund for discussion. OSBORNE Reynolds November 30 Mr. Crookes and Eva Fay If Mr. Wallace had read my letter in Nature of November 29 with a little more attention, he would have seen that I did 7iot refer to the Daily Teleg7-aph "as an authority in a matter of scientific inquiry," but that the account I gave of Mr. Crookes's "scientific tests " was given in Air, C.'s own communication to the ' Spiritualist,' which would have been reproduced without abridgment if the columns of Nature could have admitted it. What I hold myself pledged to show (in Nature, if it pleases, as well as in the new edition of my Lectures) is that the " tying-down by electricity " described by Mr. Crookes in the Spiritualist, is no more effective in preventing the performance of juggling tricks than Eva Fay's ordinary tying-down under which her tricks were publicly reproduced two years ago by Messrs. Maskelyne and Cooke. And since Mr. Crookes made no mention of the extraordinarily sensitive galvanometer he UFcd, v/hich is described for the first time by Mr. Wallace in the last number of Eraser, I only consider myself bound to show the method by which, with ordinary apparatus, the electric test may be evaded — the trained skill of the acute trompcuse being very probably required to meet the more severe test now first specified. Mr. Wallace seems to me to have been a little hasty on another point. " The supposed exposure of Eva l"ay in America," he says, " was no exposure at all, but a clumsy imitation." As this is merely Mr. W.'s dictum founded upon an imperfect newspaper report, I prefer to trust the judgment of the eye-witnesses who have publicly testified to the completeness of the exposure. Among these are not only three of the ablest men in New York (the Rev. Dr. Bellows, Ex-Surgeon-General Mott, and Dr. Ham- mond), but the reporters of the very newspaper referred to which had previously shown a decided leaning to the claims of spiri- tualism. And their judgment is confirmed by the fact (which Mr. Wallace probably considers as a newspaper fiction, but of which I have mdependent testimony) that Eva Fay was forcca by the local authorities to take out a licence as a juggler as a con- dition of the continuance of her public performances. The fundamental difference between Mr. Wallace and myself as to the validity of testimony in regard to the "occult" comes out so strongly in this case that we have really no coinmon Dec. 13. 1877] NATURE 123 ground for a discussion which I cannot consider it profitable to continue. WiLLIAM B. CARPENTER The Glacial Geology of Orkney and Shetland Owing to an accident I did not see your number of Sep- tember 13 containing my letter on the glacial geoloj^y of Orkney and Shetland and Prof. Geikie's article (vol. xvi. p. 414), until my return from Scotland a few days ago. Otherwise 1 should have troubled you sooner with a few observations thereon. In tbe first place I wish to thank Prof. Geikie for the very courteous manner in which he has referred to the remarks of an outsider who has ventured to intrude on what the Professor has made, to such an extent, his own peculiar province. In the next place I am glad to find that upon what was the most important fact in my statement, viz., the absence cf ra sed beaches or other signs of recent elevation of the land in Orkney, Prof. Geikie agrees with me. I call this the most important because it bears directly on the theory cf wide-spreid changes in the relative level of sea and land owing to secular causes, such as a change in the axis of the earth's rotation, or in the position of its centre of gravity. If it can be proved that the difference of level, which caused the raised beaches of the south of Scotland, and extt:nded north along the coast of Ross and Sutherland, dies out as we proceed further rorih, and disappears altogether in Orkney and ShetlanI, it is truly a crucial experiment which shows that these raided beaches are due to local elevations of the land, and not to a general s^inking of the sea. This is the conclusion to which Prof, Geikie points, though he naturally finds it difficult to understand why the upheaval, so marked in Sutherland, did not affect Caithness and Orkney. I believe I can add a few facts which may assist in removing these doubts. At one of the places in Caithness mentioned by Prof. Geikie, where the existence of a raised beich mij^ht be possible, viz., in the sheltered Bay, between Freswick and Wick, I believe there is one, though less strongly marked and at a lower elevation than these in similar situations in Sutherland. I allude to a terrace which bounds the links of Keiss Bay, about half a mile inland from the present coast-line. I cannot speak positively, not having seen it for some years ; but my recollection is that it is a perfect miniature reproduction of the terraces round Brora and other bays in Sutherland. If so, it is a positive proof that the elevation of the land died out towards the north, and we might reasonably suppose that somewhere about the line of the Pentland Firth was the neutral axis, on one side of which the land rose, while on the other it fell. Be this as it may, the fact is, I think, incontrovertible that Orkney did not share in the southern movement of elevation. This rests not only on the absence of raised beaches, forming terraces, which might possibly have disappeared, but still more on the absence of all traces of marine action, such as pebbles, sand, or shells, on the low plains which must have been submerged. I would ask Prof. Geikie to consider whether the single instance cf the Loch of Stennis is not conclusive. If the sea had ever stood twenty or thirty feet higher relatively to the land than it now does, the whole plain up to the hills must have been a sheltered, shallow, inland fiord. As the land rose to its present level this must have left not only a terraced beach at the foot of the hills, which might pos- sibly have disappeared (though it is hard to see why it should have done so in such a sheltered situation), but the whole plain must have been a raised sea-bottom, strewed over with pebbles, sand, and shells. These could not have disappeared, and as they are nowhere visible and the plain consists everywhere of the ordinary rock, with a thin mantle of soil resulting from its disin- tegration by ordinary atmospheric causes, I am, I think, justified in assuming it to be proved that Oikney did not share in the recent movement of elevation which affected the rest of Scotland. Now one word as to glaciation. I can assure Prof. Geikie that I do not think for a moment of setting my authority against his, and that if he is right in the instances of glaciation he tells us he has observed in Orkney, so far from being disappointed, I shall be pleased, for it will clear up what has long seemed to me a perplexing anomaly. Of course Orkney must have experienced the full rigour of the glacial period, and it is only natural to expect that it should show the same abundant signs of glaciation as the adjoining counties of Scotland. Prof. Geikie will therefore excuse me if I still retain a little of that healthy scepticism which is go con- ducive to the establishment of truth, and venture to plead that judgment may ba suspended until there is further evidence. I d'l so mainly because the Professor's own statement is that during his visits to Orkney his atttntion was devoted mainly to the old red sandstone, and his remarks on glaciation weie only inciden'aL Now there are some proofs of glaciation which are so obvious that there can be no m'stake about them, others which may easily be mistaken, and which require close examination by a practised eye directed specially to them, to arrive at a just con- clusion. Boulders of foreign rock, perched blocks, rocks unmistakably rounded and polished by the ice plane, are among the former. But strias require yreat practice and careful exami>iatiori to be sure of them in a district of finely laminated sandstones which weather constantly into parallel lines or grooves. Stony clay a^ain, from disintegrated rock, is o'^ten so like boulder clay that it requires close observation to distinguish one from the other. And finally where steep hills have crumbled away and filled up many places in the narrow valleys between them with their dibris, as at Hoy, the appearances are very like those of glacial moraines. Now I observe that nearly all the conclusive proofs of glacial action are wanting in Prof. Gi;ikie's enumeration. He has not seen, or heard of anyone who has seen, a single boulder or perched block, or even a single piece of foreign itone in Orkney. As regards boulder-clay I would join issue on his instances, taking especially that of Kirkwall Biy, btcm^e it is typical of the other cases and so easily accessible that the facts can readily be verified. I believe it to be disintegrated and not boalder clay, for the following reasons : — 1. The clay is not compact like that of genuine bouHer-clay, but of looser structure, and often clearly mide up of minute splinters of the disintegrated rock. 2. The stones in the clay are never foreign stones, and are not scattered irregularly, as if shot out into a huge rubbish heap, as in true boulder-clay, but arranged for the most pirt so that the original lines o^ stratification can be followeH. 3. If the section which resembles boulder-clay be followed up, it will be found to merge insensibly in what is unmistakably the common disintegrated surface .'■oil of the district. • There only remains the question of ro.he^ mcutonnSes, and here I speak with the greatest diffidence, for cenainly Prof. Geikie ought to know a great deal better than I whether a hummock of rock is or is not " admirably ice- worn and striated" like those behind Stromness. I can only say that I have looked at them often, and they appear to me to be very different from the roches moutonnies of which I have seen so many in Scotland, Wales, and Swiizerlan \. They are not rounded, sm )Oth, and polished, as if planed into shape by some gigantic tool, but simply irregular hummocks of rock, sometimes smooth and sometime rou^h, according to accidents in the bedding and weathering of the strata. So at least they seem to me, and even in the valleys of Hoy, where, if anywhere, there were local glaciers, the sections shown bv the small streams and low coast-line, always, I believe, exhibit the same appearance of sandstone strata, coming at an angle to tha surface, and with their edges not planed off, but passing gradually into surface soil by disintegration. Of course I make these statements subject to correction. It may be that I have failed to see things because my eye is not suffi- ciently educated. But when we couple what is, I believe, abso- lutely certain, viz., the absence of the more prominent and obvious proofs of glaciation in the form of boulders and foreign rocks, with the equally certain fact that O.kney was an excep- tion to the general rule of recent elevation, I think Prof. Geikie will admit that the interests of science will be promoted by any remarks which miy lead to reasonable doubts, and therefore to conclusive investigation, as to the fact whether Orkney does or does not give proof of having been covered by a great polar ice- sheet during the glacial period. 36, Wilton Crescent, S.W. S. Laing Explosions I HAVE been waiting to see if Mr. Galloway's paper on "Explosions in Mines" published in Nature, vol. xvii, p. 21, would lead to any conespondence. Your readers may be in- terested in an incident reported to me Jjy the late Dr. Bottinger, of Messrs. i^llsopp's brewery, Kurton-on-Trent, 124 NA TURE {Dec. 13, 1877 Tn their new brewery, near the railway station, the crushed malt is lifted from one floor to another by a series of cups revolving on a leathera .band. The casing, which incloses the banc?, is full of floating malt dust while the revolution is g >ing on, and on opening one of the doors of the casing a puff of malt- dust is sent out into the room. Soon after the brewery was opened, a workman went with an undefended light to make some examination of the working of the leathern band, and on opening the door of the cas ng an explosion followed ; not of a very serious character, but enough, I think, to throw the band cut of gear. The cause of the explosion is evident ; the rapid cox bust icn of the fine malt dust with which the air puffed out into the room was charged. Dr Bottinger died a ii^f) years since, but it would probably not be diffcult to get accurate details of the accident from Messrs. AUsopp and Sons. A. Mackennah Bowdon, December 11 Means of Dispersal In his great work, " Insecta Maderensia," Mr. Wollaston remarks upon the great affinity in the coleopterous fauna of Madeira with that of Sicily, and in his "Coleiptera H speri- dum," on the iiorthem character of that of the Cape Verde Isles. Mr. Andrew Murray also found that out of 275 Cape Verde species 91 were comm n to the Canaries and 81 to the Madeiran group. The last author would seem to rely on the efficacy of now submerged continents as a means of transmission between the two areas. Towards the end of the fifteenth and commencement of the sixteenth century, the Portuguese carried the sugar-cane from Sicily to Madeira and the Canaries, The means of introduction would probably be the same then as now ; .the young shoots of cane would be conveyed in boxes or baskets of earth from one locality to the other, as the writer once carried young cane plants from Car Nicobar vid Rangoon to Penauir, and has seen the same arrive in the last locality from the West Indies. There can be little doubt that many of these plants must have been carried from Sjcdy to the Atlantic Isles before a successful or sufficient introduction was made, and with the earth in wliich the plants were conveyed, many geodephagous and other coleoptera would find an enforced means of migration. The sugar-cane is also reported as having been introduced into Cyprus from Asia, and transplanted from there to Madeira, thus adding another link to the localities in which these colej^jteral affinities have been detected. It is not proposed th« this was. the sole, but only a probable means of the transmission of common form-; in ihe coleopteral faunas of these widely-separated districts, ; The number of causes which have been factors ,to the sa^ne in the past may be in an inverse ratio to our knowledge of thpno. W, L. Distant Supplementary Eyebrows I MET a gentleman a few days agu who has on either side of the forehead a suppleoientary eyeljrow branching off from the superciliary ridge uear the supra-orbitaL notch, and passing obliquely upwards and o itwards f r about | inch across the forehead. Beneath these brows, which contain large and coarse hairs, are lints of soft down-like hair, one on either side occupy- ing the usual position of the eyebro'vs. Since my aitenton was drawn to this subject I have noticed that many persons have a short secondary spur of hairs at the points indicated. Artists, I believe, have noticed this deviation from the normal eyebrow-lme, as we occasionally observe it in por raits of Puck and other mischievous spiitcs. There is a spot about midway between the orbits in animals that I have examih d (namely, horses, dogs, and cats), whence the lines of hair-insertion into the skin radiate in various direc- tions. If we consiler the secondary eyebrj vs of man as a reversion to an ancestral type, we must conclude that our hairy progenitors also possessed such a radiating point of hair insertion upon their foreheads, and that the secondary eyebrows are only remnants of a hairy covering which originally enveloped the whole face. W. Ainslie Hollis Brighton Diffusion or Cohesion Figures in Liquids With reference to the above, allow me to relate some experi- ments made several years ago, and easily repeated, I. Take a tall precipitate glass, fill it with water, drop into it a piece of lump or refined sugar and four or five grains of common salt. Let the vessel remain quiet, so that when the sugar is dis- solved there may be different densities in the fluid from top to bottom. Then lightly touch the surface with a piece of lunar caustic (silver nitrate), and observe the figure which results. 2, The experiment may be repeated with sugar, diluted sul- phuric acid, and barium chloride, the figures varying with the proportions of the ingredients used. 3, Take a common tumbler glass filled with water, dissolve in it half a tea-spoonful of common salt. Touch the surface of the solution with the point of a pen filled with ordinary black ink, and the characteristic figures are produced. F.R.S. Brighton, December 12 Meteor At 8h. 13m, (i; 2m.) p.m. on December 9, a brilliant meteor passed from 32 Cameleopardalis (± 1°) through m Lyrae (± i'^), and disappeared about 6° beyond ; time of passage, i"6 (± ■3) sec. ; mag.. 8 (± 2) x Lyrse ; colour, emerald green ; track, yellow, visible I second ; seen from 51° 24' 43" N., 2' 13" E. This may enable a'northern observer to fix the position. Bromley, Kent ' W. M, F. P. ON THE CAUSATION OF SLEEP THE last nutnber of Pfiilger's ArcJiiv (vol. xv., p. 573) contains the following interesting note by Dr. Striimpell : — *' In the autumn of last year there was received into the medical clinik of Leipzig a youth, aged 16, in whom variou J phenomena of anaesthesia gradually developed themselves to an extent which has very rarely been observed. The skin of the whole surface of the body was completely insensible, and that in respect to every kind of sensation. The most powerful electric current — a burning taper held to the skin — was not able to produce any pain or even a sensa- tion of touch. Almost all the accessible parts of the mucous membrane of the body exhibited the same insensibility to pain. Al-o all those sensations which are classed together under the name of ' muscular sense,' were entirely absent. The patient, when his eyes were closed, could be carried about round the room, his limbs could be placed in the most inconvenient positions without his being in any way conscious of it. Even the feeling of muscular exhaustion was lost. In addition there carhe on also a complete loss of taste and smell, amaurosis of the left eye, and deafness of the right ear. "In short, hece was an individual whose only con- nection with the otiter world was limited to two doors of sense — to his one (right) eye, and his one (left) ear. Moreover, both these remaining doors could at any time be easily closed, and in this way it was possible to inves- tigate the consequences of completely isolating the brain from all external stinmlation through the senses. I have frequently made the following experiment, and often showed it to others : — If the patient's seeing eye was bandaged and his hearing ear was stopped, after a few (usually from two to three) minutes the expression of sur- prise and the uneasy movements which at first showed themselves ceased, the respiration became quiet and regular ; in fact the patient was sound asleep. Here, therefore, the possibihty of artificially inducing sleep at any time in a person simply by withholding from the brain all stimulation by means of the senses was realised. " The awakening of the patient was as interesting as the sending him to sleep. He could be awakened by an auditory stimulation, as, for example, by calling into his hearing ear or by visual stimulation, by allowing the stimulus of light to fall upon his seeing eye ; but he could not be woke by any pushing or shaking. If he was left to himself he did eventually wake up of his own accord in course of the day, after the sleep had lasted many hours, the awakening being due, it might be, to intrinsic stimuli started in the brain, or it might be to slight external unavoidable stimuli acting through his still functional sense organs, and making themselves felt in consequence of the sensitiveness of the brain being increased during the repose of the sleep." Dec. 13 1877] NA TURE 125 THE MODERN TELESCOPE^ II. 'HETHER the telescope be of the first or last order of excellence, its light-grasping powers will be practically the same ; there is therefore a great distinction to be drawn between the illuminating and defining power. W Fig. 5.— Saturn and his moons (general view with ajfinch object-glass.) The former as we have seen depends upon size (and sub- sidiarily upon polish), the latter depends upon the accuracy of the curvature of the surface. If the defining power be not good, even if the air be perfect, each increase of the magnifying power so brings out the defects of the image, that at last no details at all are visible, all outlines are blurred or stellar character is lost. Even with the best telescopes the power should not be strained. The testing of a glass therefore refers to two different qualities which it should possess. Its quality as to ma- terial and the fineness of its polish should be such that the maximum of light shall be transmitted. Its quality, as to the curves, should be such that the rays passing through every part of its area shall converge absolutely to the same point, with a chromatic aberration not absolutely nil, but sufficient to surround objects wiih a faint violet light. With the reflector we have to consider the brilliancy of the surface and the perfection of curvature. In close double stars, therefore, or in the more minute markings of the sun, moon, or planets, we have tests of its defining power ; and if this is equally good in the instruments examined, the revelations of telescopes as they increase in power are of the most amazing kind. A 3|-inch suffices to show Saturn with all the detail shown in Fig. 5, while Fig. 6 shows us the further minute structure of the rings wh'ch coties out when the planet is observed with an object-glass with an aperture of 26 inches. In the matter 01 double stars, a telescope of 2 inches Fig. 6.— Details of the ring of Saturn observed by Trouvelot wit'i ihe 26-inch Washington Refractor. aperture, with powers varying from 60 to 100, should show the following stars double : — Polaiis. 7 Arietis. a Geminorum. o Piscium. p Herculis. 7 Leonis, )u Draconis. f Ursae Majoris. \ Cassiopeop. A 4-inch aperture, powers 80-120, reveals the duplicity of — /3 Orionis. a Lyrse. 8 Geminorum. e Hydrre. f Urise Majoris. a Cassiopeae. 6 Booti<. 7 Ceti. « Draconis. I Leon's. ' Continued from p. 68. A 6- inch, powers 240-300 — 6 Ar etis. 20 Draconis. 32 Orionis. « GemiiiOrum. A Ophiuchi. * EquuleL An 8- inch — 8 Cygni Siriu«. 7'^ Andromec'se. 19 Draconis. The " spurious disk," which a fixed star presents, as seen in the telescope, is an effect which results from the passage of the light through the circular object-glass, or its reflection Irom a circular mirror ; and it is this U 2 ^ Herculis. \ Bootis. y? Herculis. ti? Bootis. I 26 NA TURE {Dec. 13, 1877 appearance which necessitates the use of the largest apertures in the observation of close double stars, as the S'ze of the star's disk varies, roughly speaking, in the inverse ratio of the aperture. In our climate, which is not so bad as some would make it, a 6- to an 8-inch glass is doubtless the size which will be found the most constantly useful ; larger apertures being frequently not only useless, but hurtful. Still, 4 or 3I inches are apertures by all means to be encouraged ; and by object-glasses of these S'ze5, made, of course, by the best makers, views of the sun, moon, planets, and double stars, may be obtained, sufficien ly striking to set many seriously to work as amateur observers, and with a prospect of securing good, useful results. Observations should always be commenced with the lowest power, gradually increasing it until the limit of the aperture, or of the atmospheric condition at the time, is reached. The former may be taken as equal to the number of hundredths of inches which the diameter of the object-glass contains. Thus, a 3f-inch object-glass, if really good, should bear a power of 375 on double stars where light is no object ; the planets, the moon, &c., will be best observed with a much lower power. Fig. 7. — Appearance of diffraction rings round a star when the ob- ject-glass is properly adjusted. Fjg. 8. — Aopearance of same object when object-glass is out of adjust- ment. Care should be taken that the object-glass is properly adjusted. And we may here repeat that this may be done by observing the image of a large star out of focus. If the light be not equally distributed over the image, or the diffraction rings are not circular, the screws of the cell should be carefully loosened, and that part of the cell towards which the rings are thrown very gently tapped with wood, to force it towards the eyepiece, or the same purpose may be effected by means of the set-screws always present on large telescopes, until perfectly equal illumina- tion is arrived at. This, however, should only be done in extreme cases ; it is here especially desirable that we should let well alone. In the case of mirrors, instructions for adjustment are generally given by the maker. The convenient altitude at which Orion culminates in these latitudes renders it particularly eligible for observa- tion ; and during the first months of the year, our readers who would test their telescopes will do well not to lose the opportunity of trying the progressively difficult tests, both of illuminating and separating power, afforded by its various double and multiple systems, which are collected together in such a circumscribed region of the heavens that no extensive movement of their instruments — an important point in extreme cases — will be necessary. Beginning with 8, the upper of the, three stars which form the belt, the two components will be visible in almost any instrument which may be used for seeing them, being of the second and seventh magnitudes, and well separated. The companion to /3, though of the same magnitude as that to S, is much more difficult to observe, in consequence of its proximity to its bright primary, a first magnitude star. Quaint old Kitchener, in his work on telescopes, mentions that the companion to Rigel has been seen with an object-glass of 2|-inch aperture; it should be seen, at all events, with a 3-inch. . The bottom star in the belt is a capital test both of the dividing and space-penetrating power, as the two bright stars of the second and sixth magnitudes, of which the close double is composed, are exactly 2|" apart, while there is a companion to one of these components of the twelfth magnitude about I" distant. The small star below, which the late Admiral Smyth, in his charming book, " The Celestial Cycle," mentions as a test for his object-glass of 59 inches in diameter, is now plainly to be seen in a 3|. The colours of this pair have been variously stated. Thit either our modern opticians contrive to admit more light by means of a superior polish imported to the surfaces of the object-glass, or that the stars themselves are becoming brighter, is again evidenced by the point of light, preceding one of the brightest stars in the system composing or. This little twinkler is now always to be s?en in a 3|-inch, while the same authority we have before quoted — Admiral Smyth — speaks of it as being of very difficult vision in his instrument of much larger dimensions. In this very beautiful compound system there are no less than seven principal starr ; and there are several other faint ones in the field. The upper very faint companion of X is a delicate test for a 3|-inch, which aperture, how- ever, will readily divide the closer double of the principal S'ars which are about 5" apart. These objects, with the exception of t, have been given more to test the space-penetrating than the dividing power ; the telescope's action on 52 Orionis will at once decide this latter quality. This star, just visible to the naked eye on a fine night, to the right of a line joining a and S, is a very close double. The components of the sixth mignitude are separated by less than two seconds of arc, and the glass which shows a good wide black divisioi between them, free from all stray light, the spurious disc being perfectly round, and not too large, is by no means to be despised. Then, ag^in, we have a capital test object in the great nebula to which reference has already been made. The star to which we wish to call especial attention is situate (see Fig. 4) opposite the bottom of the " fauces," the name given to the indentation which gives rise to the appearance of the " fish's mouth." This object, which has been designated the "trapezium," from the figure formed by its principal components, consists, in fact, of six stars, the fifth and sixth (y' and a) being excessively faint. Our previous remark, relative to the increased brightness of the stars, applies here with great force ; for the fifth escaped the gaze of the elder Herschel, armed with his powerful instruments, and was not discovered till 1826, by Struve, who, in his turn, missed the sixth star, which, as well as the fifth, has been seen in modern achromatics of such small size as to make all comparison with the giant telescopes used by these astronomers ridiculous. Sir John Herschel has rated y' and d of the twelfth and fourteenth magnitudes— the latter requires a high power to observe it, by reason of its proximity to a. Both these stars have been seen in an ordinary 5-foot achromatic, by Cooke, of 3f-inches aperture, a fact speaking volumes for the perfection of surface and polish attained by our modern opticians. Let us now try to form some idea of the perfection of the modern object-glass. We will take a telescope of eight inches aperture, and ten feet fo:al length. Suppose vye observe a close double star, such as | Ursse, then the images of these two stars will be brought to a focus side by side, as we have previously explained, and the distance by which they will be separated will be dependent on the focal length of the object-glass. If we take a telescope ten feet long and look at two stars 1° apart, the angle will be 1° ; and at ten feet off the distance between the two images will be something like 2j'j5 inches, and therefore, if the angle be a second, the hues will be the girVo^^ P^""^ ^^ ^^^^j o'^ about Yv^oa^h part Dec. 13, 1877] NA TURE 127 of an inch apart, so that in order to be able to see the double star ^ Ursas, which is a i" star, by means of an eight-inch object-glass, all the surfaces, the 50 square inches of surface, of both sides of the crown, and both sides of the flint glass, must be so absolutely true and accurate, that after the light is seized by the object-glass, we must have those two stars absolutely perfectly distinct at the distance of the seventeen hundredth part of an inch, and in order to see stars ^'' apart, their images must be distinct at one-half of this distance or at uj^y^th part of an inch from each other. J. Norman Lockver ( To be continued. ) BIOLOGICAL NOTES Classification of Decapod Crustaceans.— In this well-defined group, the position of the anomurous forms (hermit-crabs, &c.) has often been the subject of doubt. The special adaptations of some genera for particular modes of life have caused them to be thrown together ; and no doubt they agree in possessing neither the powerful abdomen of the lobsters, nor the very much aborted one of the crabs. Yet the anomurous forms include markedly contrasted groups. The family HippidcC, with its lobster-like cephalothorax and firm abdomen, differs greatly in aspect from the hermit-crabs. Hippa talpoida, a small species found along the whole eastern coast of the United States, inhabits sandy beaches exposed to the waves, at a zone very near low-water mark. It has a smooth oval form, and short and stout thoracic legs (second, third, and fourth pairs), enabling it to burrow backwards in the sand with marvellous rapidity. In life the antennae are peculiarly crossed, with the flagella curved round the mouth so that the setae, with which they are densely covered, all project inwards, and the function of the antennas appears to consist chiefly in the removal of all parasitic growths or foreign bodies from the anterior parts of the body. The appendages of the mouth are not adapted for prehension or mastication, and the alimentary canal is found loaded with fine sand. The thoracic appendages have neither external nor superior elements (exopodites, epipodites) ; while the ofifice of protecting and cleaning the gills is discharged by the small Umbs corresponding to the fifth pair of ambulatory legs in lobsters, which are curved upwards and hidden beneath the carapace. The development of this form has been recently carefully described by Mr. Sidney Smith, of Yale College, in the Transactions of the Connecticut Academy, vol. iii. p. 311. They pass through larval stages very analogous to the zoea stages of crabs, only being destitute of a large dorsal spine j and they then assume a form like the brachyuran megalops, with large eyes, and powerful abdominal swimming legs. But in this condition they buried themselves in sand with great alacrity. Thus it is determined that the embryonic development of Hippa, as well as of Albunea, studied by Claus, agrees much more closely with that of crabs proper than with hermit crabs or lobsters ; and this publication by Mr. Smith furnishes an important addition to the evidence favouring the view that the Anomura are a heterogeneous group made up of specialised families of Brachyura and Macrura. The American Bison.— Mr. J. A. Allen's valu- able " History of the American Bison," so sump- tuously produced by the Geological^, Survey of Kentucky and the Harvard Museum of Zoology, has excited so much interest that to supply the demand for it Dr. Haydan has republished almost the whole of the text in the ninth annual report of his survey of the territories, and as a separate pamphlet of 150 pages, with con- siderable additions by the author. One of the most interesting of these consists in the publication of a letter from Mr. J. W. Cunningham, of Howard County, Nebraska, on the domestication of this species. It appears that the bison has been crossed with the ordi- nary milch cow, and that half- and quarter-breds are not uncommon, and the cows yield extremely rich milk. They prove to be both hardy and tame. The colour of the bison and the majority of the distinguishing characters disappear after repeated crossings. The lump of flesh covering the dorsal vertebrae also becomes diminished. The preservation of a pure domestic breed of the bison does not seem so easy. In some instances where buffa- loes have been broken to the yoke they have proved strong and serviceable, but rather unmanageable at times. Unless the breed is maintained in some way artificially, the wild species will no doubt before very long become extinct. Products of Assimilation in Musace^.— Herr Emil Godlewski has recently investigated whether in the case of Musaceas the first assimilation-product is oil or starch, which latter is the first product in most plants. Sig. Briosi had recently maintained that oil was first pro- duced. The question which had to be solved, therefore, was whether these plants, when decomposing carbonic acid under the influence of light, exhale a volume of oxygen greater than that of the carbonic acid decomposed. If oil is formed from the carbonic acid this must be the case. Measurements which Herr Godlewski made to this end with Musa sapientium, gave negative results ; the oxygen exhaled was not of greater volume than the carbonic acid decomposed. Sig. Briosi had failed to discover starch in the grains of chlorophyll of the mesophyll-cells of the leaves ; while Herr Godlewski was perfectly successful also in this direction, perceiving numerous granules of starch in leaves from young specimens of species of both Musa and Strelitzia, which had been collected in the evening after a hot day. Fertilisation in Thyme and Marjoram.— Under the title of " Das Variiren der Gro;se gefarbten Bliithen- hiillen, und seine Wirkung auf die Naturziichtung der Blumen," Dr. Hermann Miiller reprints from Kosnios a paper containing many of the facts which have appeared from time to time with his signature in these columns. The special point to which he calls attention is the occurrence in many species of \.z!o\2X^— Thymus ser- pyllum, Origanum vul^are, &c. — of two distinct forms, one with larger hermaphrodite protandrous, the other with smaller female flowers. The second of these two forms can manifestly only be fertilised by the former, and will disappear where the conditions of life are unfavour- able ; while the propagation of the first form is in no way dependent on the other. A Fossil Fungus.— One of the most interesting re- cent discoveries in palaeophytology has recently been made by Mr. Worthington Smith, in the detection, in the coal- measures, of a fossil fungus nearly allied to that which produces the potato blight, and which he has named Peronosporites antiquarius. Fossil fungi were not pre- viously altogether unknown. Some years ago Mr. Car- ruthers, the keeper of the botanical department at the British Museum, detected mycelial threads among the cells of a fossil fern {Osmunda) from the Lower Eoceiie strata of Heme Bay ; and Mr. Darwin has stated that fungus threads in a fossil state in silicified wood were shown to him more than forty years ago by the late Mr. Robert Brown. Messrs. Hancock and Atthey have also described in the Annals atid Magazine 0/ Natural History (4th ser. vol. iv. 1869, p. 121, t. ix. X.), under the name of Archa- garicon, what may be a fossil Peronosporites from the Cramlington black shale. The specimen examined by Mr. Worthington Smith (the fungoid nature of the organism having been first suggested by Mr. Carruthers), was seen within the vascular axis of a Lepidodendron, 128 NATURE {Dec. 13, 1877 and is thus described by that gentleman : — It consists of a mass of mycelia and zoosporangia (or oogonia). Be- ginning with the mycelium, a close examination shows that it is furnished with numerous joints or septa. If, therefore, any reliance is to be placed upon the modern distinguishing characters of the now living species of the genera Peronospora and Pythium, as furnished by a septate or non-septate mycelium, the fossil parasite belongs to the former, and not to the latter genus, nor to any of the Saprolegnicce. The oogonia do not agree with those of Cystopiis. Within many of the fossil oogo- nia the differentiation of the protoplasm into zoospores is clearly seen ; but if any doubt could exist as to the exact nature of this differentiation, then other oogonia (or zoosporangia) on the same slide show the contained zoo- spores with a clearness not to be exceeded by any living specimens of the present time. It is a very remarkable fact that the oogonium precisely resembles, in size and other characters, average oogonia of the present day, especially those belonging to Peronospora infestans. The contained zoospores are, moreover, the same in form and dimensions with those of P. infestans when measured to the ten-thousandth of an inch. The organisms are, in fact, apparently identical ; and the average number of zoospores in each oogonium is also the same, viz., seven or eight. The aerial condition of the fungus has not yet been observed. Mr. Worthington Smith suggests, in conclusion, that we probably have, in Peronosporites antiqiiarius, one of the primordial plants from which both the great families of fungi and algae may possibly have descended ; but should not this primordial plant have led a non-parasitic life 1 — for if parasitical, then this fact points to some pre-existing plant. The Laws of Digital Reduction.— Hitherto there has been little explanation of the curious variation in the number and relative size of the digits in the vertebrata. Mr. John A. ^yAtr {American Naturalisi, October) suggests that the number of toes is least where the mechanical strains are greavest, and impacts most frequent and severe. He quotes several cases in which the hinder digits are reduced more than those of the fore feet, and shows that in all of them the body in jumping or running pitches mainly upon the hind limbs. He looks upon the outer toes of man as in process of undergoing reduction, being now v/eaker and shorter than in any of the higher apes. The chrysochloris among moles is an instance of special reduction in the anterior extremity, and here the mecha- nical strains are most frequent and severe. Among fossorial animals the claws and toes are usually best developed on the fore limbs. The retention by certain groups, of digits in a very equal state of development in manus or pes, or both, is attributed to the equal distribu- tion of strains on all. The Birds of Guadaloupe Island.— This inter- esting fauna is dealt with by Mr. Robert Ridgway in the Bulletin of the Nuttall Ornithological Club for July. It is strange that only eight forms from this island, situated about 220 miles south-west of San Diego, are satisfactorily known, and their affinities are almost entirely with those of western North America. They are recognised by Mr. Ridgway, however, as specifically distinct, differing from their nearest mainland allies in the (i) increased size of the bill and feet, (2) shorter wings and tail, and (3) darker colours. The Distribution of Freshwater Fishes.— Dr. D. S. Jordan, the well-known American ichthyologist, has contributed to the American Naturalist for October some of his conclusions derived from long study of the fishes of rivers flowing in different directions, and under the most widely- varied physical conditions. He finds that in the case of rivers flowing into the ocean, the character of the fishes of the upper waters bears little or no relation to the place of discharge. The higher or the older the watershed between two rivers, the fewer species are com- mon to both. Certain species (not including species of general distribution) occur on opposite sides of even the highest watersheds. When the watershed between two rivers is a swampy district, the same species are found ia the head waters of both, though the faunas of the lower courses may be distinct. There is often a great differ- ence between the forms in the upper and lower waters of a river, owing to differences in physical conditions. Some species are strictly confined to one river basin ; others are widely distributed. Usually the more southern rivers have the most peculiar and varied faunas. Species of the widest distribution often have breaks in their range which cannot be accounted for by any known facts. The characteristically American forms of freshwater fishes are, generally speaking, absent or rare in the waters of New England and of the Pacific slope. The larger the river-basin, the greater its variety of forms. Seventy species have been taken in the little White River at In- dianopolis, representing forty-eight genera, twice as many as occur in all the rivers of New England. Other things being equal, a river whose course lies in a region of undisturbed stratified rocks, or of glacial drift, contains most genera and species. Certain forms appear generally distributed in a definite range, either without regard to the direction in which the rivers flow, or even bounded by parallels of latitude. In any river-basin the most abundant species (of small fishes) are usually (i) those peculiar to it, or (2) those of widest distribution. Earwigs (Forficulid^). — Linnaeus seems to have known but two species of earwigs {Forficula au7-iculata and minor). Both were European, and had Elytra dimi- diata et AIcb tectce, and were placed among the beetles (Coleoptera). There are nowabout 250 species known which are found all over the world, and grouped in about thirty genera, of which the genus Forficula is by far the richest in species and the widest in its geographical distribution. Happily, too, it still retains the two first-named species, and it has also most justly given its name to the family. Entomologists will be glad to know that Mr. Samuel Scudder has just published a series of critical and his- torical notes on this family, in which he gives descriptions of all the known genera, and an alphabetical list with full synonyms of all the described species ; this most valuable list will make the study of these interesting insects an easy one. It is published in Parts 3 and 4 of vol xviii. of the Proceedings of the Boston Society of Natural History. Hungarian Spiders.— The first part of a work on Hungarian Spiders by Assistant-Director Otto Hermann, of Buda Pest, has just reached us. It forms a handsome royal-quarto volume, with three plates, and is printed in double columns, one in Magyar, and the other, fortu- nately for us, in German. This volume forms part of the T?'ansactions of the Royal Hungarian Natural History Society, which is really to be congratulated on the appearance of this and the next work that we will mention. The present volume gives a sketch of the literature belonging to spiders, and forms one of the most generally interesting portions of the work, for it is most carefully elaborated, being divided into the bibliography of the older and the newer times. It further treats of the life-history of spiders in general, and of the geographical distribution of those species to be met with in Hungary. The next volume will contain the spiders met with in Hungary proper, Hungarian Rotifers or Wheel- Animalcules. — A memoir on Hungarian Rotifers by Dr. Bartsch Samu is also published under the auspices of the Royal Hungarian Natural History Society, but it is v/ritten exclusively in Magyar, if we may except a short appendix containing brief descriptions of the new species determined by the author, and therefore unfortunately we can do no more than call attention to it. Dec. 13, 1877] NATURE 129 OUR ASTRONOMICAL COLUMN The Satellites.— The following table presents at one view the mean distances of the satellites from their primaries, expressed in equatorial semi-diameters of the latter, and founded upon the most reliable data hitherto available : — The Earth. Mars. Jupiter. Saturn. Uranus. Neptune. T. ir. TIL ... — IV. ... — V. ... — VI. ... — VII. ... — VIII. ... — 6027 ... 272 6 8i 570 ... 2-98 ... 771 ... 14-55 9'o7 •••■ 3"83 ••• 1075 ••• — 14-46 ... 475 ••• 1763 ... — 2544 ... 608 ... 23 57 ... — — ... 8-47 ... - ... - — ... 1967 ... — ... — — ... 24-80 ... — ... — — ...5728 ... - ... - It will be seen that the outer satellite of Saturn, lapetus, is the only one revolving round its primary at a distance similar to that of our moon, with respect to the semi-diameter of the central body. The exterior satel- lites of Jupiter and Uranus are similarly placed in this respect, and as regards the former planet the reader will remember a suggestion of Sir John Herschel's, that a distant satellite, by which was intended one situate more nearly, as our moon or the Saturnian satellite lapetus, might be " worth a search." At the end of the last century it was thought that if satellites of Mars existed they might be " distant many degrees from the principal planet," upon which idea the late Prof. D'Arrest argued that a search after a satellite situate many degrees from Mars would be an almost endless task ; and further, that a satellite at a maximum digression of seventy minutes of arc would have a sidereal period greater than the synodi- cal revolution of the primary. The same astronomer endeavoured to ascertam, at the opposition of 1864, to what magnitude stars were visible in the vicinity of Mars with the Copenhagen refractor, which has an aperture of about eleven English inches. He considered that a satel- lite as bright as the twelfth magnitude could hardly have escaped him, and that objects of a fainter class were only visible in such an instrument at distances of eight or ten minutes, and in the case of Mars opportunities of viewing a satellite in such position would occur compara- tively seldom. Perhaps the more prevalent idea respecting possible satellites of Mars, prior to their actual discovery, was that they would be " very small and close to the planet." (Hind, in " Solar System," p. 78.) Tycho Brake's Star of 1572. — It is to be hoped that the vicinity of the famous star in Cassiopeia, with which we are accustomed to associate Tycho Brahe's name, may continue to receive frequent attention, and in particular that the small star, which at present is so near to the most accurate position we are able to obtain of the star of 1572, may be assiduously watched and its bright- ness determined from time to time by comparison with its neighbours, and not merely by estimation of magni- tude. It was Bessel who, as he states in a letter to Olbers, in 1824, first engaged Argelander to work up the position of the Nova Cassiopeiae, with all possible pre- cision. Forty years later Argelander revised his calcula- tions with improved positions for trie reference-stars, and obtained a result differing in no material degree from the earlier one. The small star alluded to is so near to Argelander's last position |(differing only fifty seconds of arc), as to be within its possible limits of error ; it is No. 129 of the catalogue of stars in the vicinity which was pre- sented to the Copenhagen Academy in January, 1864, and an eleventh magnitude on Bessel's scale. It will be most readily identified by means of the star of the ninth magnitude. No. 300 of Oeltzen's Catalogue from Argelan- der's northern zones, the position of which for 1878-0 is in R,A. oh. 17m. 32s., N.P.D. 26° 22'-6 ; the suspicious object follows Argelander's star 29-65., and is south of it 10' 4". The place of Nova for 1878-0 is in R.A. oh. i8m. 2-is., N.P.D. 26° 31' 43". The Austrian Comet-medal.— We have received from the Imperial Academy of Sciences at Vienna, the conditions upon which that body has resolved to renew, until further notice, the prizes for the discovery of tele- scopic comets, and which appear to be similar to those originally issued in June, 1872. The awarding of a prize, which will consist, according to the wish of the receiver, in a gold medal or its money value of twenty Austrian ducats, is connected with the following condi- tions : (i) Prizes will be awarded only for the first eif^ht successful discoveries in each calendar-year, for comets that at the time of their discovery were telescopic, ie. invisible to the naked eye, that had not been previously seen by any other observer, and which could not have been predicted, and it is important to observe that in the case of independent discoveries priority is to be decided by^the epoch of the first position. (2) The discovery must be communicated to the Academy of Sciences imme- diately, by telegraph, where practicable, otherwise by the earliest mail, the Academy undertaking to make it known without delay to several observatories. (3) This first notice must necessarily contain the position and motion of the comet as accurately as they are known, with the place and time of discovery, and is to be supplemented at the next opportunity by later observations. (4) If the discovery should not have been verified by other ob- servers, the prize will only be adjudged 'Svhen the observations of the discoverer are sufficient for deter- mining the orbit." (5) The prizes will be awarded in the general sitting of the Academy held at the end of May in each year, and in cases where the first intimation of the discovery arrives between March i and May 31, the award will be decided in the general May session in the following year. (6) Application must be made for the prize to the Imperial Academy within three months after the first notice of discovery shall have reached it, later applications being rejected. Finally, the astronomers of the observatory of the University of Vienna are appointed judges, whether the conditions in (i), (3), and (4) have been fulfilled. GEOLOGICAL WORK OF THE U.S. SURVEY UNDER PROF. HAYDEN DURING THE SUMMER OF 1877 'X*HE necessity of a careful examination of the various -^ geological formations in the field, and a review by a practical palaeontologist of the various districts that have from year to year been surveyed by the different geologists of this and other surveys, has been long felt. Such a work, indeed, was imperatively necessary, before a con- sistent and comprehensive classification of the formations could be estabhshed. This duty was assigned to Dr. C. A. White, the palseontologist of this survey, and he took the field at the beginning of the past season and con- tinued his labours until its close. The special duty with which he was charged was to pursue such lines of travel as would enable him to make critical examination of the geological formations in succession as they are exposed to view on both sides of the Rocky Mountain chain, and also on both sides of the Uinta chain ; to collect and study the fossils of these formations in such detail as to settle, as far as possible, the questions of the natural and proper vertical limits of the formations, their geographical range, their correlation with each other, and to define the palEeontological characteristics of each. He has pursued his researches with such success during the past season as to demonstrate the necessity of con- tinuing this class of investigations by various lines of travel across what is generally known as the great Rocky Mountain region, especially those portions of it that have I30 NATURE [Dec. 13, 1877 been surveyed, as well as those in which surveys are in progress. Among other important results, he has shown the identity of the lignitic series of strata east of the Rocky Mountains, in Colorado, with the Fort Union group of the Upper Missouri River, and also its identity with the great Laramie group of the Green River Basin and other portions of the region west of the Rocky Mountains. He also finds the planes of demarcation between any of the niesozoic and cenozoic groups, from the Dakota to the Bridger, inclusive, to be either very obscure or inde- finable ; showing that whatever catastrophal or secular changes took place elsewhere during all that time, sedimentation was probably continuous in what is now that part of the continent, from the earhest to the latest of the epochs just named. The general course of travel pursued by Dr. White during the season was as follows, not including the nu- merous detours, meanderings, and side trips, which the work necessitated. Outfitting at Cheyenne, he journeyed southward, traversing in various directions a portion of the great plain which lies immediately adjacent to t>^e eastern base of the Rocky Mountains in Colorado. The most easterly point thus reached was some sixty miles east of the base of the mountains, and the most southerly point, about twenty-five miles south of Denver. Return- ing to Denver to renew his outfit, he crossed the Rocky Mountains by way of Boulder Pass, through Middle Park. After making certain comparative examinations of the mesozoic and cenozoic formations in Middle Park, he proceeded westward to the head-waters of Yampa River, following that stream down to the western foothills of the Park Range of mountains. Here, resuming his compara- tive examination of the mesozoic and cenozoic strata, he passed down the Valley of the Yampa as far as Yampa Mountain, one of those peculiar and remarkable upthrusts of palaeozoic rocks through mesozoic strata. In all this area, as well as that between the Yampa and White Rivers, the Laramie group reaches a very great and characteristic development ; and it received careful investigation, yielding some of the most important results of the season's work. Crossing the ground between the two rivers named, to White River Indian Agency ; thence down White River Valley about 100 miles, thence to Green River, crossing it at the southern base of the Uinta Mountains, making many detours on the way, he reviewed the geology of the region which he had sur- veyed during the previous season. This review brought out not only the important palsontological facts before referred to but it also added materially to the elucidation cf the geological structure of the region which lies between the eastern end of the Uinta mountain range on the west, and the Park range on the east. Beyond Green River he pursued his travels westward, studying the mesozoic and cenozoic strata that flank the Uinta range upon its south side, and making comparisons of both their lithological and palccontological charac- teristics. In this way he traversed the whole length of the Uinta range, crossing at its junction with the Wasatch range over into the valley of Great Salt Lake. Re-crossing the Wasatch to the north side of the Uinta range, he con- tinued his examinations of the cretaceous and tertiary strata into and entirely across the Great Green River basin, leaving the field at the close of the season at Rawlin's station on the Union Pacific Railroad. A general statement of the results of the season's work has been given in a previous paragraph, but the following additional summary will make the statement somewhat clearer, being made after the route of the season's travel has beeii indicated. The formations of later mesozoic and earlier cenozoic ages, especially those to which Dr. White, in former publications, has applied the provisional designation of " post-cretaceou?," have received par- ticular attention. The extensive explorations or' \iv. Hayden in former years, and the palseontological in- vestigations of the late Mr. Meek, pomted strongly to the equivalency of the Fort Union beds of the Upper Missouri River with the lignitic formation as it exists along the base of the Rocky Moun- tains in Colorado ; and also to the equivalency of the latter, with the Bitter Creek series west of the Rocky Mountains. The investigations of the year have fully confirmed these views by the discovery not merely of one or two doubtful species common to the strata of each of these regions, but by an identical moUuscan fauna ranging through the whole series, in each of the regions named. This shows that the strata just referred to all belong to one well marked period of geological time ; to the strata of which Mr. King has applied the name of " Laramie group" (Point of Rocks, Group of Powell). His in- vestigations also show that the strata which in former reports by himself and Prof. Powell, have been referred to the base of the Wasatch group, also belong to the Laramie group, and not to the Wasatch. He has reached this later conclusion not merely because there is a simi- larity of type in the fossils obtained from the various strata of the Laramie group with those that were before in question ; but by the specific identity of many fossils that range from the base of the Laramie group up, into, and through the strata that were formerly referred to the base of the Wasatch. Furthermore some of these species are found in the Laramie strata on both sides of the Rocky Moun- tains. Thus the vertical range of some of these species is no less than three thousand feet and their present known geographical range more than a thousand miles. Besides the recognition of the unity of the widely dis- tributed members of the formation of this great geological period, bounded by those of undoubted cretaceous age below, and those of equally undoubted tertiary age above ; his further observations have left comparatively little doubt that the "lake beds" of Dr. Hayden, as seen in Middle Park, the " Brown's Park group " of Prof. Powell, and the " Uinta group" of Mr. King, all belong to one and the same epoch, later than, and distinctly separate from, the Bridger groups. In that portion of the region which lies adjacent to the southern base of the Uinta mountain range, and which is traversed by Lake Fork and the Du Chesne River, not only the Uinta group, but both the Green River and Bridger groups also, are well developed, each possessing all its peculiar and usual characteristics, as seen at the typical localities in the great Green River Basin, north of the Uinta Mountains. This, added to the known existence of Bridger strata in White River Valley, and the extensive area occupied by the Green River group between White and Grand Rivers, has added very largely to our knowledge of the south- ward extension of those formations. In all the comparative examinations of the formations or groups of strata that have just been indicated he has paid special attention to their boundaries or planes of demarcation, crossing and recrossing them wherever opportunity offered, noting carefully every change of both lithological and palaeontological characters. While he has been able to recognise with satisfactory clearness the three principal groups of cretaceous strata, namely, the Dakota, Colorado, and Fox Hills, on both sides of the Rocky and Uinta Mountains respectively, they evidently constitute an unbroken series so far as their origin by continuous sedimentation is concerned. While each of the groups possesses its own peculiar palaeontological characteristics, it is also true that certain species pass beyond the recognised boundaries of each within the series. The stratigraphical plane of demarcation between the Fox Hills, the uppermost of the undoubted cretaceous groups, and the Laramie group, the so-called post- creta- ceous, is equally obscure ; but the two groups are pa'aeon- Dec. 13, 1877] NATURE 131 tologically very distinct, inasmuch as the former is of marine origin, while the latter, so far as is now known, contains only brackish-water and fresh-water invertebrate forms. He reports a similar obscurity or absence of a stratigraphical plane of demarcation between the Laramie and Wasatch groups, although it is there that the final change from brackish to entirely fresh waters took place over that great region. Furthermore, he finds that while the three principal groups of the fresh-water tertiary series, west of the Rocky Mountains, namely, the Wasatch, Green River, and Bridger groups, have each peculiar characteristics, and are recognisable with satis- factory dist^nct^le^s as general divisions, they really con- stitute a continuous series of strata, not separated by sharply-defined planes of demarcation, either stratigra- phical or palaeontological. During the progress of the field work, as above indi- cated, large and very valuable collections of fossils have been made, all of which will constitute standards of reference in the future progress of the work, and quite a large number of the species are new to science. These are now being investigated,, and will be published in the Usual paljeontological reports of the survey. NOTES At the moment of going to \ ress"we have received the report of the Inflexible Committee. The impression a first glance over it gives is that the Inflexible is a passable ship, but that the Committee strongly urge the Admiralty not to proceed with any more like it, which practically puts an end, we presume, to the Ajax and Agamemnon, in their present form, as well as to the fourth ship which the Admiralty proposed to build. It is proper, however, to state that a closer perusal of the report shows the hiflexible herself to be open to the gravest objections in several respects, and that the Committee recommend considerable modi- fications in her. In our next number we shall /uUy review the report. Wk have received several letters 'from India, showing that great interest is being taken in that country with reference to the best methods of determining the amount and variation of solar radiation. We may state that both Prof. Stewart and Mr. Lockyer have recently devised instruments to secure these data. The latter proposes to utilise Capt. Abney's method of obtaining photographs of the red end of the spectrum, so that variations in thermal and chemical intensity may both be recorded auto- matically. Sir William Thomson has been elected a Foreign Associate of the Paris Academy of Sciences, to fill the place vacated by the death of von Baer. Prof. Sir Wyville Thomson has been created a Knight of the Royal Order of the Polar Star by the King of Sweden. M. Tempel is^ to continue henceforth the publication of Donati's Bollettino of the Arcetri Observatory, of which only one number had been issued when Mr. Donati died. Gen. Nansouty, Director of the Observatory situated on the top of the Pic du Midi has been nominated '* Officier de rUniversite " by M. Faye, the new Minister of Public Instruc- tion. The General, as our readers know, spends his winters on that precipitous mountain for meteorological observations. We are glad to register such anacknowledgment of his devotion to science. Dr. Burdon-Sanderson gives notice that the first of his annual course of lectures on comparative pathology will be de- livered at the University of London, Burlington Gardens, on Saturday, December 15, at half-past five o'clock. The subject of the lecture will be, "The Infective Processes of Disease." The succeeding lectures will be on the Monday, Wednesday, and Friday of the following week, at the same hour, for which days "The Nature and Causes of Septic Infection," "The Germ Theory," and "The Theory of Contagium Vivum," are among the topics to be discussed. The German postal department has issued a complete series of regulations for the use of the telephone in the various offices where it has been established. In § 15 we notice the rule that the speaker shall pronounce each syllab e slowly and separately, and make a pause at the end of evtry six words to give lime for the receipt of the me.-sage. The receiver repeats the whole message at the end at an ordinary rate of delivery. Proper names and foreign messages are spelled. The Pontmasier- General, Dr. Stephan, who wages an unmerciful war in his department against all foreign words where a German equivalent is possible, has christened the new invention as the Fernsprecher (far-speaker), and excluded entirely tha^ Greek telephone ivoxa. his regulations. In consequence of the large numbers who were unable to obtain admission to the recent lecture at the Society of Arts on the "Telephone," Prof. Bell, at the special request of the Council of the Society, has consented to repeat his lecture on Wedne-day, the 19th inst. As there is certain to be a large attendance, it is suggested that those members who heard the first lecture, should refrain from exercising their privilege of being present on the second occasion. Prof. Kekuli^:, of Bonn, the originator of the present benzene theory has been nominated for president of the German Chemical Society for the coming year. The policy which the society adopted at its last annual election of choosing its chief officer from among the leading German chemists at a distance from the headquarters of the society, seems to meet general favour, and Prof. Wohler, the Nestor of organic chemistry, will certainly be ably succeeded by Prof Kekule, whose classical researches and theoretical deductions form the basis of the present atomistic theory. The German Chemical Society would do well to copy one of the customs of its sister society in London, viz., to require an inaugural address from its newly-elected presidents. We notice that the library of the society will be enriched by the bequest of the extensive chemical library of the late Prof. Oppenheim, an accession which will double the present number of volumes. Dr. Vohl, of Cologne, has adopted an ingenious method of determinin:^ the impurities in the Rhine, which consists ia analysing the boiler incrustations of the river steamers, as well as the concentrated residues i-emuning in the boilers after passing over a certain distance. By this means he has detected the presence of a large amount of arsenious acid in the river water — resulting chiefly from the aniline and dyeing establishments— a; well as other poisonous substances. An unusually high per- centage of phosphoric acid showed that the sea waj daily absorb- ing vast quantities of the most valuable fertilising material from the soil of Germany. The Scientific Congress of France will meet at Nice from January 10 to 20, 1878. The locality is likely to attract many visitors at such a cold period of the year. Another sitting of the enlarged Council of the Observatory of Paris was held on December 9. The councillors passed a resolution for an increase of the salary of the astronomers and auxiliary astronomers, the maximum pay of the former to be^ 10,000 francs instead of 8,000, and of the second 7,000 instead of 6,000. They propose to the Government to place the appointment of the director of the establishment partly in the hands of the Academy of Sciences and partly in the hands of the Council, the Minister to have only the privilege to choose 132 NA TURE \Pec. 13, 1877 between both presentations. It should be remembered that under the former organisation the appointment of the director was in the hands of the Bureau des Longitudes, which had to designate yearly their member to preside over the observations. Arago and his illustrious predecessor held their office by a yearly tenure, renewed up to the time of their death. It was only Leverrier who was appointed by the Government ; under the old monarchy the director was appointed by the Ung, A proposal was made for suppressing the general assembly of astronomers, which was established by M. Leverrier, and is to be held at Easter at the Ministry of Public Imtruction. The proposal was out-voted. At the next sitting the long-discussed organisation of meteorology will be introduced ; the existing order of things continues to enjoy the support of the majority. A TKLEGRAM from Alexandria states that Capt. Burton has started from Suez for Moilah on a second expedition to Midia, accompanied by many Europeans and a large number of native workmen and troops. A depot will be formed at Moilah in the Gulf of Akaba, and the expedition will extend to the second range o^ mountains hitherto unexplored. Capt. Burton expects to discover a rich mineral country between the two ranges of mountains. He will be absent four months. The Montpouris Park, in the centre of which the Montsouris Observatory has been erected, is almost ready for public use. Admittance to the observatory grounds will be procured on application to the secretary, for the purpose of inspecting the instruments and the working of the meteorological observations. In Wiirteniberg a remarkable property of ripe grapes has been recently discovered, which the agricultural authorities have now i published, so that all proprietors of vineyards may derive benefit S from being acquainted with it. It appears that if ripe grape?, which have become frost-bitten, are kept for a little time in some j dry place, they entirely lose the bad effects caused by the frost. In the Bulletin of the French Geo,:Traphical Society for October are some interesting notes from the Abbe Desjgodins, on Tibet. The Abbe gives some information concerning the Brahmapootra, which he obtained from an old lama, whom he believes to be thoroughly trustworthy. This lama has travelled much, and visited nearly the whole of Tibet. His information j^oes to prove the identity of the Yar-tsiou-tsang-po with the Brahmapootra. He has followed the great river from its source in or near the lakes of Tso-ma-pang in the west of the province of Ngare, the most western of Tibet, and in making his pilgrimages he has reached the frontiers of the savage tribe of the Lhopa. The lama states that some days to the east of Lassa the river turns towards the south, making a great bend, and traverses the well-peopled and rich district of Hia-zul, just to the north of the Lhopa. Passing through the latter district, it flows among steep and rugged r^cks, and after a certain distance forms a great waterfall. This faU of the Yar-kiou-tsang-po, M. Desgodins lias no doubt, is identical with the fall of Brama-Khoond, well known to the Assamese. The lama affirmed that the river did not reach so far as the Nahengs (Mishmis), but that it disap- peared more to the west, among the Lhopa. The lama gave the Abbe, besides, much information concerning the people and the districts through which the river passes. The Bulletin con- tains, besides, a learned article by M. E. Cortambert on some of the geographical monuments of the middle ages in the National Library, dwelling at considerable length on the well- known Mappemonde of Beatu=, a beautiful facsimile of which is given. The Italian Geographical Society has received letters from Aden dated November 25, which confirm the arrival of the second Italian (Martini-Cecchi) expedition at Far^e. There is no news ?it all about the supposed de''eat of King Menelik of Schoa in connection with which the death of the Marquis Antinori was reported. It seems, however, that King Kassa gained a victory over a Prince Menelik (son of the late Kirg Theodor), who had rebelled in Kassa's camp. The resemblance of names explains the misunderstanding and deprives of any foundation the news about the misfortune said to have happened to the members of the first Italian (Antinori) expedition. The French Acclimatisation Society held its anniversiry meeting on December 7 last, under the presidency of M. Quatrefages. The Society lost recently M. Drouyn de Lhuys, one of its founders, a former minister of the empire, well known in France as well as abroad. In this month's Geographical Alagazine Mr. C. R. Markham continues his valuable papers on Irrigation in Southern India, and Mr. G. J. Morrison concludes his interesting description of the island of Formosa. In criticisinT; Mr. Trelawney Saunders on the question of ** Water-partings versus Ranges," Mr. R. B. Shaw appears to have misconceived Mr, Saunders' statements ; Mr. Saunders' knowledge is too extensive and accurate to allow him to maintain the identity of the two terms. Sir George Nares contributes an important article on the Greenland Foehn, recently noticed in Nature. We are glad to learn from the Geographical Magazine that the Dutch are making active preparations to resume Arctic explora- tion, to which they have been able to do little since the days of the brave but unfortunate Barentz, and nothing at all, we believe, during the last century. A new schooner is to be built to be sent out in May next year to make a summer cruise in the Spitzbergen and Barentz Seas. The hygrometer devised by M. AUuard, described in Nature, vol. xvii. p. 14, was constructei by M. L. Golaz, of 24, Rue des Fosses St. Jacques, Paris, who contributed some beautifully- constructed apparatus to the recent Loan Collection at South Kensington. Dr. Schliemann, assisted by Mr. Streatfield, of the Science and Art Department, is busy arranging his Trojan treasures in the South Kensington Museum. Although a large space has been assigned for their reception, it will take considerable in- genuity to get all the interesting articles satisfactorily arranged. ■ M. Dahlander communicates to the Swedish Academy of Sciences the results of his observations on the comparative rapidity with which heated solid bodies are cooled by immersion in various liquids. If the cooling power of water be taken as unity, that of alcohol is 0*58, of mercury 2*07, of a concentrated solution of salt, 1*05, and of a concentrated solution of sulphate of copper, I 03. The rapidity of the cooling increases with the increased temperature of the liquid. The twenty-first annual report of the committee of the PVee Public Libraries and Museums of Sheffield, speaks favourably of the progress of these institutions. We are glad to see that the number of scientific works sought for both in the lending and consulting libraries bears a fair proportion to the number in other departments. According to the published reports of the Koenigsberg Board of Trade, the total production of amber in the province of Prussia amounted to 135 tons during the year 1876, of which eighty-five tons were furnished by one mine alone, viz., the mine of Palmnicken. This production considerably exceeded that of the previous year. The amber was exported principally to Austria, Fiance, Russia, America, China, and Japan, while the export to India, Persia, and Australia does not pay the pro- ducers, and is therefore extremely limited. The number of workmen in the province who are employed in the production of amber amounts to nearly 1,400. Now that the struggle in the East seems to be reaching its crisis, the fine, large, clear map of the Bosphorus and the Dec. 13, 1877] NATURE 133 Dardanelles, just published by Mr. Stanford, will be extremely useful to those who desire to follow, with intelligence, further movements, military or diplomatic. Mr. Heighway's handbook of "Practical Portrait Photo- graphy " (London, Piper and Carter), has reached a second edition, into which some improvements have been introduced. TllE death is announced of Mr, John G. Anthony, who for same years has had charge of the conchological department of the Cambridge Museum. He was one of the party accompanying Prof. Agassiz in his celebrated scientific expedition to BraziL The number of French communes receiving the daily warn- ings of the international service for agricultural purposes is increasing daily ; the death of Leverrier has not destroyed that extraordinary movement. It is said the twenty districts into which Paris has been divided, will very soon have the daily warnings posted at'each of their respective mairies. Ac- cording to a saying attributed to M. Dumas, ' The existing meteorology had had -t own plebiscitum. " Prof. J. Plateau, of Ghent, has reprinted (from the Pro- ceedhigs of the French Association for the Advancement of Science, 1876) a paper on the question, Is the instinct of insects deceived by artificial riowers ? As far as the series of experi- ments performed by him — rather few in number, but apparently carried out with great care — can ba relied on, although insects may be attracted from a distance by the bright colours of arti- ficial flowers, they are never tempted by the resemblance to alight on them in the hope of obtaining food from them. He concludes, therefore, that insects make use of some other organ than that of sight in the selection of the flowers which they visit. Prof. E. Morren, of Liege, has issued the fifth annual edition of his " Correspondance Botanique," which contains a complete list of botanical gardens and museums, and the occu- pants of botanical chairs throughout the world. Even adding a number of "unattached" English botanists whose names are given, it is instructive to compare the number engaged in botanical research in Great Britain with that in France or Irermany, or even in Italy or Russia. A BRIEF report of the third annual conference of the Crypto- amic Society of Scotland, held at Dunkeld in October last, has een published, from which it is evident the meeting was success- il. The first fasciculus of the " Fungi Scotici Exsiccati" will be published in January. Dr. Buchanan White, Perth, will receive orders ; no subscribirs names cxa be received after the 20th inst. We have received Part 2, 1876-77, of the Transactions of the Cumberland Association ol Literature and Science, which con- tains a number of scientifii: pipers of cons derable value. Among these are six original papers cummunica'ed to the socie- ties connected with the Association during the session, and selected by the Council for publication. Two of the,'uiing his la*e trip to Venezu.la,"' In Ac Atti della Reale Academia del Lined at Rome, some interesting investigations are described, which were made by Messrs. A. and G. De Negri at the Chemical Laboratory of the Genoa University, on the purple dies of antiquity. The authors have thoroughly investigated the subject ; after an elaborate account and an enumeration of the various historical data with regard to the molluscs from which the ancients obtained thtir purple colours, they enter into a discussion of the chemical and optical properties of these substances, the methods of dyeing with them, the adulterations found in them, and various other detail} concerning them. We must refer our readers to the original treatise for further particulars, as our space will not permit us to enter into them. The paper is accompanied by a number of plates, giving the spectra of the colours obtained irom species of the genera Applysia and Murex. The same volume of this publication contains an excellent account, by Signor C. Bagnis, of the fungi species Pucdnia, illustrated by no less than eleven well-drawn plates. The Piscicultural Institution of Schwerin has recently made some important experiments with a view to ascertain whether the artificial culture of river Crawfish {Astacus fluviatilis) is possible on a large scale. The experiments were entirely suc- cessful. In the spring of last year some 700 crawfish with ova were placed into two circular ponds of only six feet diameter, and for each animal a separate hole had been constructed. At the end of November the ponds were drained in order to separate the young crawfish from the old ones. It appeared that of the latter only three or four were crawling about at the bottom of the pond while all the others had occupied their respective dwellings. The young were of the size of a bee and extremely lively ; they were taken out of the ponds and already on the following day could be fed artificially with carrots and meat. Many a land or garden proprietor could thus make crawfish- culture a lucrative pastime at very little cost, particularly since the consumption of these crustaceans increases largely every year. The last number of the Zeitschrift fiir Ethnolo^ie contains a most valuable and elaborate review of the entire ethnological and anthropological literature of 1876, prepared by Prof. W. Koner. Over 1,000 pamphlets, periodicals, and books are referred to, and as few subjects are handled ia a greater variety of languages than those in question, the labour of compiling such a report can easdy be imagined. We have received the third (final) part of Herr Axel Blytt's elaborate Flora of Norway, which is published by order of the Royal Norwegian Society of Science--, and bears the title, "Norges Flora ; eller Beskrivelser af de i Norge vildtvoxende Karplanter" (" Flora of Norway; or, Description of the Wild Plants in Norway.") A CORRESPONDENT asks where he can find a description of the mode of drying sections of tree?. He has a transverse sec- tion, three inches thick, of an elm tree, and he wants to dry it so that it may be cut in veneer when ready. The additions to the Zoological Society's Gardens during the past week include a Diana Monkey {Cercopithecus diana) from West Africi, presented by Mr. Walter Mayhew ; a Rhesus Monkey {Alacacut erythrceus) from India, presented by Mr. R. S. Cox ; two White Storks ( .'iconta alba), a Common Heron {Ard^a ctnerea), a Greater Black-backtd Gull (Larus marinus), European, presented by Mr. C. Clifton ; a Hobby {Hypotriorchis subbuteo), captured at sea, presented by Mr. W. Renney ; two Lesser Sulphur-crested Cockatoos {Cacatiia sulphurea) from the Moluccas, presented by Mrs. Roberts ; seven Gelada Baboons (Cynocephalus gelada) from Abyssinia, four Barbary Turtle- Ddves ( Turtur risorius) from North Africa, deposited ; two Schlegel's Doves (Chakopelia puella) from West Africa, purchased. 134 NATURE [Dec. 13, 1877 UNIVERSITY AND EDUCATIONAL INTELLIGENCE Cambridge.— The examination for open scholarships at Christ's College will be held on Tuesday, April 9. Candidates in natural science will be required to show a satisfactory know- ledge of elementary chemistry, both theoretical and practical. Candidates are required to send in their names to one of the tutors o' the college before April 2. Further information can be obtained on written application to Mr. John Peile, or the Rev. J. W. Cartmell, Christ's College. Science and Art Department. — The list has been pub- lished by the Science and Art Department of the successful can- didates in honours at the examination of science schools and classes. May, 1877. We give the names of the two first in the first class of each subject : — Subject I. Practical, Plane, and Solid Geometry — ^John R. Smith, age 32, clerk; William J. Last, age 19, engineer. Subject II. Machine Construction and Drawing — Robert A. Sloan, age 22. engineer ; Will am Sisson, age 24, engineer. Subject III. Building Construction — Crichton Walker, age 34, carpenter ; Robert Henry, age 22, draughtsman. Subject IV. Naval Architecture — Frederick B. Ollis, age 18, shipwright's apprentice; George A. Agnew, age 23, shipwright's apprentice. Subject V. Pure Mathematics, Stages One, Two, and Three — George J. T. Harker, age 18, student ; Arthur W. Ward, age 18, cotton broker. Stages Four and Five — Frederick W. Watkin, age 18, pupil ; Arthur E. Holme, age 18, engineer. Subject VI. Theoretical Mechanics — William Sisson, age 24, engineer ; William Martin, age 22, engineer. Subject VII. Applied Mechanics — Frank W. Dick, age 23, engineer ; Fred Ogden, age 18, engineer, William J. Last, age 19, engineer, Robert A. Sloan, age 22, engineer, Robert Greei)halgh, age 22, engineer — eq. Subject VIII. Acoustics, Light, and Heat — Frederick E. Boughton, age 20, draughtsman ; James Greer, age 31, Inland Revenue officer. Subject IX. Magnetism and Electricity — Robert A. Sloan, age 22, engineer, Frederick E. Boughton, age 20, draughtsman— eq. ; William J. Last, 19, engi- neer. Subject X. Inorganic Chemistry— Charles N. Luxmore, age 19, chemist's as^sistant ; Sidney E. Meates, age 17, chemical student. Subject XI. Organic Chemistry — Charles M. Luxmore, age 19, chemist's assistant. Subject XX. Navigation — George Goodwin, age I4, eneineer's apprentice ; William AUingham, age 26, clerk. Subject XXII. Steam— Robert A. Sloan, age 22, engi- neer, William Sisson, age 24, engineer — eq. ; Alfred Cliff, age 22, engineer, Jerdan Nichols, age 21, engineer — eq. Subject XXIll. Physical Geography — John S. Harper, age 19, student in training; John Sharkey, age 29, schoolmaster. Subject XXIII, Physio- graphy— George A. Freeman, age 26, schoolmaster ; John A. Lakin, age 21, teacher, Fredk. J. Richardson, age 16, teacher — eq. Subject XXIV. Principles of Agriculture — Edward S. Chesney, age 21, student ; William E. Akroyd, age 20, student. There have been no first class successes in Geology, Mineralogy, Animal Physiology, Elementary Botany, General Biology, Principles of Mining, Metallurgy, and Nautical Astronomy. Bristol. — The annual meeting of the governors of University College was held on Friday last, when a report, on the whole satislactory, was presented. The number of students has some- what decreased, as indeed might have been expected, but there seems every reason to believe that the college has taken its place as an important centre of education in the west of England. The funds of the college, though considerable in amount, are yet not sufficient to keep it going with complete efficiency, and we hope the appeal made by the governors will be satisfactorily responded to. It is proposed to make the college a local xeutre for the examinations of the University of London. : ^f »;• j-j, Pesth.— A commission has recently been appointed by t&e various faculties, to make fitting preparations for the celebration of the first centennial of the opening of the university, which was performed by Maria Theresa m 1780. The university is wealthy, possessing property to the amount of 6,000,000 florins, and a library of 120,000 volumes, and forms the real centre of Hun- garian intellectual life. The other two Hungarian universities, Klausenberg and Agram, were founded respectively in 1872 and 1874. At present the instructors number 150 and the students 2,630. WiJRZBURG.— Prof. Sachs has declined the call to the vacant chair of botany at the Berlin University, and the authorities are still seeking a successor for the late Prof. Braun. SOCIETIES AND ACADEMIES London Royal Society, December 6. — Points of resemblance between the suprarenal bodies of the horse and dog, and certain occa- sional structures in the ovary, by Charles Creighton, M. B., Demonstrator of Anatomy, Cambridge University. Communi- cated by Prof. Humphry, F. R.S. On the tides at Malta, by Sir G. B. Airy, K.C.B., Astronomer- Royal. Observations on hermetically-sealed flasks opened on the Alps, in a letter to Prof. Huxley, Sec. R S., by Prof. Tyndall, LL. D., F.R. S. Though the author believes the question of "Spontaneous Generation" is practically set at rest for the scientific world, he has been making some experiments on Bacteria. He took with him this year to the Alps sixty hermetically- sealed flasks, containing infusions, of beef, mutton, turnip, and cucumber, which had been boiled for five minutes and sealed during ebullition. These were kept for six weeks, when some were opened in a haylo t and others on the edge of a precipice. The two groups of flasks were then placed in the author's kitchen, where the temperature varied from about 65° to 90° Fahr. Theresult was that twenty-one of twenty-three flasks opened in the hay-loft were filled wiih organism ; two of them remained clear. All the flasks opened on the edge of the precipice remained as clear as distilled water. Not one of them gave way. Chemical Society, December 6. — The President in the chair. — The following papers were read : — On gallium, by W. Odling. The properties of the metal, i's chloride, and sulpha'e, and their reactions, were given and specimens exhibited. — On nitrifi- cation, a report of experiments conducted in the Rothamsted Laboratory, by R. Warrington. Schloesing and Miintz have shown that nitrification is due to the action of an organised fer- ment whose action is suspended by chloroform. The author has completely confirmed the above statement, and has proved that carbolic acid and bisulphide of carbon also stop the action of the ferment, and moreover that darkness is essential for the process. The author has succeeded in converting a dilute solution of am- monium chloride into a nitrate by seedmg it with some earth from a fairy ring and keeping it in the dark for three months. — On potable waters, by E. J. Mills, D. Sc. The author investi- gates the minute errors incidental to the process of Frankland and Armstrong with great care, suggests a new form of evaporator, and arrives at three natural constants or ratios of organic carbon to organic nitrogen in potable waters. — On some derivatives of allylacetone, by J. R. Crow. By the action of sodium, a secon- dary alcohol homologous with allyl alcohol was prepared ; its acetate and dibromide were also investigated. — On a fourth method for estimating bismuth volumetrically, by M. M. P. Muir. The bismuth is precipitated as oxalate, the latter on boiling is converted into a basic oxalate, the precipitate is well washed, dissolved in hydrochloric acid, and the solution titrated with permanganate. — On the gas of the Grotto del Cane, by T. G. Young. This gas contains 61-71 per cent, of carbonic acid, the residual- air having the compoiition oxygen, 20*25, nitrogen, 7975. — Note on tetrabromide of tin, by T. Carnelly, D.Sc, and L. T. O'Shea. This body was obtained as a colour- less liquid, solidifying to a mass of colourless crystals,— melts at 30'' C, boils at 201°. Meteorological Society, November 21. — Mr. H. S. Eaton, M.A., president, in the chair. — The following gentlemen were elected Fellows of the Society, viz. : — E. D. Archibald, B.A., R. W. P. Birch, Capt. W. F. Caborne, H. Clarke, L.R.C.P., Cohen de Lissa, F.S.S., R. Gordon, J. Hunter, jun., J. J. Lake, Rev. E. A. D. O'Gara, O.S.B , R. Pcnnmgton, LL.B., E. E. Prichard, and Rev. S. J. W. Sanders^ — The following papers were read : — On the general character and principal sources of variation in the weather at any part of a C) clone or anti-cyclone, by the Hon. Ralph Abercromby, F. M.S. In a cyclone the broadest feature of the weather, as seen on a synoptic chart, is an area of rain about the centre surrounded by a ring of cloud, beyond which the sky is clear. The precise form and position of these areas vary with the t>peof pressure distribution, with the intensity of the cyclone, and with the rate of its pro- gress ; they are also influenced by local, diurnal, and seasonal variations, the general sphere of each of which is indicated. By recordirg the appearanc; to a single observer of any pait of a Dec. 13, 1877] NATURE ^D cyclone as it pasfees over him, it is dtscdvered that the «rea of rain and cloud-ring may be divided into two portions — the front and rhe rear — differing in physical appearance and general cha- racter of the weather by a line drawn through the centre, in front of which the barometer is falling and in rear of which it is rising. Details are given and it is shown that this character remams constant whatever changes the variations above mentioned may effect. In anti-cyclones synoptic charts sho^v great irregularity in the positions of cloud, &c,, owing to local, diurnal, and other variations, but to a single observer, who considers the surrourd- jngs and physical appearance, a certain general character can be discovered in every part. A marked contrast is shown to exist between the diurnal variation of the weather in a cyclone or anti-cyclone, and a probable connection is pointed out between the diurnal variation of the weather and the diurnal variation of the barometer. — On a remarkable barometric oscillation on January 30, 1876, by Robert H. Scott, F.R.S. At 8 A.M. a remarkable dip appeared in the barometric curve for Armagh. The total amount of reduction of pressure was "097 inch in 25 minutes and for a portion of the time, from 8'5 to 810, the fall was '058 inch, being at the rate of '697 inch per hour. On looking to the other barograms, it was found that while a very similar oscillation of slightly greater amplitude, '102 inch, appeared at Aberdeen at noon, almost exactly four hours subse- quent to the occurrence at Armagh, hardly a trace of disturb- ance could be detected in the barogram for Glasgow, and yet the last-named observatory lies almost on the direct line between Armagh and Aberdeen. The barograms for Stonyhurst and Halifax showed as little disturbance as Glasgow. At Dunecht Observatory the oscillation took place somewhat earlier and exhibited less intensity than at Aberdeen. At Bidston, however, which lies more out of the probable path of the depression than Stonyhurst, the oscillation is seemingly recorded with consider- able distinctness. Temperature showed no appreciable change at Armagh, Glasgow, or Aberdeen. At the time of occurrence of the minimum a temporary change of direction and increase of velocity of the wind is recorded both at Armagh and Aberdeen. — The "arched squalls " of the neighbourhood of the trade-winds and of those regions where the monsoons blow with slight force and with interruptions, by Capt. A. Scniick. Physical Society, December i. — Prof. G. C. Foster, pre- sident, in the chair. — Prof. Graham Bell exhibited and described the telephone before a crowded meeting of the Society, prefacing his account of the apparatus now so well known by a very com- plete historical sketch of the progress of electric te'ephony. The first experiments referred to were those of Prof. Page, who, in 1837, was studying the relation of electricity to magnetism, and found that if a coil of wire, traversed by a current, surrounds an iron rod, a sound like a pistol shot proceeds from this latter when- ever the current is made or broken. He was followed by De la Rive, Poggendorff, Reiss, and others, but Reiss was the first to employ the human voice in his experiments. After pointing out that in transmitting sounds by electrical means the initial sounds ih mselves are in no sense transmitted but are only employed to generate currents which reproduce similar sounds, Pfof. Bell proceeded to examine the phenomena which take place when sounds are transmitted through the air. It is, of course, not the motion of the vocal organs themselves that is received in the ear, but that of the air set in motion by their means, and all pecu- liarities in the sound must be peculiarities in the motion of that air. If the rapidity of motion varies it occasions a variation in the pitch, and the loudness is changed by ichanging the ampli- tude. The shape of the vibration produces timbre. If by moving the air in certain specified ways, certain vowel sounds are given out, then those same sounds will be emitted if an identical movement be occasioned by any mechanical means whatever, and Prof. Bell has found that such a motion may really be given to the air in various ways. Three classes of electrical currents have been employed for transmitting sounds to a distance, and these he denominates intermittent, pulsatory, and undulatory. The first form is obtained when a current passes for a brief interval, is then followed by an interval during which no current passes, and this by a current of the same or opposite sign. In the second class a current is con- tinually pas-sing, but its intensity mcreafes and decreases instan- taneously, and finally, in the third class this variation takes place gradually, and may therefore be represented by a sinuous line. In his experiments on the nature of the movement of the air i?rof. Bell employed a human ear, a hay sfyle attached to the Incas recoryihg the movement commtmlcated to it tfti a moving sheet of smoked glass. A very interesting series of curves pro- duced by this means was shown upon the screen, and he explained ho V his experiments in this direction led him to the present form of telephone. Since the very small membrane of the ear wa^ capable of setting in motion comparatively large bones, it seemeid probable that it could cause a li;^ht piece of iron to vibrate. In the earlier form of apparatus a piece of steel spring was therefore attached to a stretched membrane of gold-beaters' skin and placed in front of the pole of the magnet, but he found on increasing the area of metal that the action of the instrument was improved, and thus was led to do away with the membrane itself. Another branch of the investigation referred to the strength of the magnet employed, and this was modified by varying the strength of current. The battery was gradually reduced from fifty cells to none at all, and still the effects were observed, but in a much less marked degree ; the action was in this latter case, doubtles?, due to residual magnetism, hence, in the present form of apparatus, a permanent magnet is employed. Lastly, the effect of varying the dimensions of the coil of wire was studied, when it was found that the sounds became louder as its length was diminished ; a certain length was, however, ulti- mately reached beyond which no improvement was effected, and it was found to be only necessary to inclose one end of the magnet in the coil of wire. A number of diagrams were pro- jected on to the screen which showed the various forms the apparatus has taken from the time of Page to the present day. An air sung in a distant part of the building was distinctly heard in the room by the aid of an improved form of Reiss' telephone, lent by Prof. Barrett, and made by Mr. Yates, of Dublin. Prof. Bell, Prof. Foster, and Dr. Gladstone then carried on a conver- sation with a gentleman at a distance, and utterances were shown to be audible when the transmitting instrument was held about a foot from the mouth. A discussion then followed in which Mr. De la Rue, Dr. Gladstone, Profs. Foster, Guthrie, Atkinson, and others took part. In replying to the various questions, Prof; Bell stated that his attempts to determine the amplitude of the vibrations had not been successful, and he is coming to the con- clusion that the movement must be molecular. Very distinct sounds are emitted when a considerable mass of iron is employed ; and further, if the iron be glued to a piece of wood an inch thick and this be interposed between it and the magnet the action still continues. Conversation has been carried on through a distance of 258 miles, but a resistance of 60,000 ohms has been inter- posed without preventing the action. There is a very marked difference in the manner in which letters are reproduced by the telephone. Vowel sounds are more acceptable than consonants, and, as a rule, those letters are be.it transmitted which involve a large oral aperture in their utterance. Finally, he finds that high sounds are produced more fully than low ones, but this question has not yet received sufficient attention. Zoolog**cal Society, December 4^.— Prof'. Nev^ton, F.R.S., vice-president, in the chair. — Mr. Henry Seebohm, F.Z'S., ex- hibited and made remarks upon some of the rarer eggs and birds which he had obtained during his recent visit to the Arctic regions of the Yen-e-sey, in Eastern Siberia, and gave a rapid sketch of his journey. Some of the skins were interesting from the fact that they extended our knowledge of geographical dis- tribution, such as Phylloscopus trochilus and Acrocephalus schce- nobcE7ius, from long. 88° E., Antkus gustavi of Swinhoe [A. seebohmi of Dresser, and A. batchianensis of Gray) from the same longitude, and young in fir^t plumage of this species. — Mr. Saville Kent, F.Z. S., exhibited the plans of a Zoological Station and Museum and Institute of Pisciculture to be esta- blished at St. rielier's, Jersey. The object sought in the establishment of this institution was the provision within British waters of facilities for pursuing marine biological investigations similar to those which exist at the Zoological Station of Naples, and at the Ander.-en School of Natural History at Penikese Island, Buzzards Bay, U.S.A. — The Secretary exhibited, on the part of Mr. Andrew Anderson, F.Z.S., some specimens of natural history collected in India, amongst which were chicks of Rhviichops and specimens of Podiceps cristatus obtained breeding in North-Western India. — A communication was read from Mr. Henry Lee, F.Z.S., containing an account of the capture of a Risso's grampus at Sidlesham, near Chichester. — Mr. A. G. Butler read a paper in which he gave an account of a collection of lepidoptera made in Northern Formosa by Mr. H. E. Hobson. — A communication was read from the Matquis of Tweeddale, 136 NATURE [pec. 13, 18^7 F.R.S., containing an account of a collection of birds made by Mr. A. H. Everetc in the I4ini of Mindanao, Pnilippines. Eight nejif species were found in this collection, and were named Tanygnathus everetti, MuUeripicus fuliginosus, Penelopides affinis, Criniger evere'.ti, Orthotomus ni^riceps, ^tkopyga bella, Antho- threptus griseigularis- zxi6. Ftilopus incognitus. Geological Society, November 21. — ^John Evans, F.R.S., vice-president, in the chair. —Oswald Fitch, John Hadkinson, B. Holgate, H. F, Parsons, M.D., and Edgar P. Rathbone, were elected Fellows of the Society. — The following communica- tions were read :— On the glacial deposits of West Cheshire, together with lis's of the fauna found in the drift of Cheshire and adjoiding counties, by W. Shone, F.G.S. — The chair was then taken by Warington W. Smyth, F.R, S. — The Moffat series, by C. Lap worth, F.G.S. Victoria (Philosophical) Institute, Decemlier 3. — Mr. C, Brooke, M. D., F.R. S., in the chair. The paper of the evening was read by Mr. J. E. Howard, F.R.S., and referred to the advances that modern science had made in regard to nature, and the value of " a slow but sure path of induction." Paris Academy of Sciences, December 3. — M. Peligot in the chair : — The following papers were read : — On artificial pro- duction of corundum, ruby, and different crystallised silicates, by MM. Fremy and Feil. In a crucible of refractory earth is put a mixture of equal weights of alumina and minium, and calcined for some time at a bright red heat ; after cooling there are found two layers, one vitreous, formed chiefly of silicate of lead, the other crystalline and often presenting geodes full of beautiful crystals of alumina. To obtain the red colour of ruby, about 2 to 3 per cent, of bichromate of potash is added to the mixture of alumina and minium. The silicate of lead on the ruby crystals is removed by the action of fused oxide of lead, hydrofluoric acid, or otherwise. A silicate of alumina (appa- rently dysthene) is produced by heating for some time a mixture of equal weights of silicon and fluoride of aluminium (fluoride of silicon is disengaged). Other reactions with fluoride5 giving crystalline bodies are described. — On invariants, by Prof. Sylvester. — On various means of accelerating the service in navigation-locks, by M. de Caligny. — Sir William Thomson was elected foreign associate, in room of the late von Baer, receiving twenty-seven votes against twenty-five for M. Van Beneden. — Report on a memoir of M. Hautefeuille, on reproduction of albite and orthose, M. Hautefeuilie's process consists in keeping the elements of these minerals (free or com- bined), in presence of certain fused salts, such as tungstic acid and the alkaline tungstates. Thus a mixture of silica and alumina, in presence of an acid tungstate of potash at a temperature between 900° and 1,00.0° produces tridymite, orthose, and triclinic felspars. If the elements have been exactly propor- tioned, the tridymite and felspar disappear, and their elements go to increase the crystals of orthose. — On the law of absorption of radiations through bodies, and its use in quantitative spectrum analysis (first part), by M. Govi. This relates to a comparison of the curves of abiorpiion given by wedge-shaped forms of the absorbent sub>tance. — Practical tracing of the circle which has to be substi- tuted for a given curve of finite extent, by M. Lecomte. — Batteiy in which carbon is the electrode attacked, by M. Jablochkoff. Into fused nitrate of potash or nitrate of soda is placed, as the attackable electrode, ordinary coke, and as the unattackable, plaiina. Tne electromotive force varies between two and three units, and thus exceeds that of the Bunsen and Grenct batteries. The coke may be lit and put in the nitrate in a powdered state. The gases developed by the battery are utilised. The containing vessels are of iron (that for the carbon, of iron wire). — Action of oxa.ic acid on silicate of soda, hydrated quartz, by M. Monier. — On M. Allaire's new method of puriiication of fatty water of surface-condensers, by M. Hetet. — On the respiration of submerged aquatic plants, by M. Barttielemy. These plants, observed in the normal state, do not liberate gas, even in sun- light, any more than aquatic animals (the liberation ob-erved hitherto has been caused by experiment). The true respiratory act ot these plants consists in absorption of air in solu- tion in the water, probably by the roots. — A new one-liquid battery, by M. Jourdan. The electrodes are zinc and black- lead, the liquid an aqueous solution of sal alkali. — Occu.ta- tions ; graphic prediction, by M. Baills. — Observations of the spots and the rotation of Mars during the opposition of 1877, at the Rio de Janeiro Observatory, by M. Cruls. The time of rotation obtained from three values is 24h. 37m. 34.S. — On a fundamental problem of geodesy ; application of a general method of transformation of integrals depending on square roots (continued), by M. Callandeau. — On the rational integrals of the problem of geodesic lines, by M. Levy. — On the superficial tensions of aqueous solutions of alcohol and fatty acid^, by M. Duclaux. — On some properties of boric acid, by M. Ditte. A lecture experiment *is recommended, which demonstrates the liberation of heat in chemical actions. It is to add 125 grammes of water to loo grammes of boric acid. The heat is such that an ingot of Darcet's alloy put into the mixture is fused in a few seconds. — On the formation of ultramarines and their coloration, by M. Guinet. — On the alterations of eggs, a propos of note by MM. Bechamp and Eustache, by M. Gayon. — On the mechanism of death produced by inoculation of anthrax in the rabbit, by M. Toussaint. — On some new mammalia of New Guinea, by M. Milne Edwards. — On compound machines, their economic pro- duce, and the general conditions of their action, by M. de Fre- minviUe. — Process of registration and reproduction of pheno- mena perceived by hearing, by M. Cros (sealed packet). Geneva Society of Physics and Natural History, October 4. — M. Alphonse Favre has found on the Allelin Mountain, dominating the upper part of the Saas Valley near Mont Rosa, a bed of euphotide. This name is applied to a rock formed of two element'^, viz., saus- surite, a leaden gray mineral, and diallage, a bright green mineral, classed among amphibolites. This bed explains the origin of the erratic blocks of that substance, which are seen in numbers in the plain occupied formerly by the Rhone glacier. — Prof. Wartmann showed two apparatus based upon the properties recently recognised by him among derived currents. One is intended to determine immediately the fraction of an electrij current which traverses a given conductor. The other is a current-inverser, in which the production of the extra-current is avoided, because the current always finds its passage. CONTENTS Pace Hydrophobia • . • < 117 Ancient History FROM THE Monuments . 119 French Popular Science 120 Our Book Shelf : — Eden's " Fifth Continent, with the Adjacent Islands; being an Account of Australia, Tasmania, and New Guinea, with Statisti- cal Information up to the Latent Date" ■ izi Higgins's " Notes by a Field Naturalist in the Western Tropics " 121 Letters to the Editor : — The Radiometer and its Lessons. — Prof. Osbornb Reynolds, FR.S i-'i Mr. Crookes and Eva Fay.— Dr. Wilhaii B. Carpenter, FR.S 122 The Glacial Geology of Orkney and Shetland. — S. Laing, MP.. 133 Explosions. — A. Mackennah 123 Means of Dispersal.— W. L. Distant 124 Supplementary Eyebrows. — W. Ainslik Hollis 114. Diffusion or Cohesion Figures in Liquids.— F.R.S 124 Meteor.— W. M. F. P 124 On the Causation of Sleep 124 The Modern Telescope, II. By J. Norman Lockyer, F.R.S. {IVith. {llustrations) 125 Biological Notes : Classification of Decapod Crustaceans 127 The American Bison 127 Products of Assimilation in Musicese 727 Fe tiiisation in Thyme and Marjoram 127 A Fossil Fungus 127 The Laws of Digital Reduction 128 The Birds of Guarfaloupe Island 128 The Distribution of Freshwater Fishes 128 Earwigs (Forficulidae) 128 Hungarian Sjiders 128 Hungarian Rotifers or Wheel-Animalcules 128 Our Astronomical Column : — The Satellites 129 Tycho Brahe's Star of 1572 129 The Au>,trian Comet-medal 129 Geological Work of the U.S. Survey under Prof. Hayden during THE Summer OF 1877 129 Notes 13' University and Educational Intelligence 134 Societies and Academies ■ • - 134 NA TURE "^n THURSDAY, DECEMBER 20, 1877 THE ''INFLEXIBLE" ON July 12 last we explained the Inflexible case at some length to our readers on the ground that there might be seen in it the beginning of a system which not only involved the safety of the four large and costly ships then commenced or contemplated, but which " having received countenance and sanction in the highest quarters in this country, may not improbably become extended over the navies of the world." A week later we considered the Parliamentary Papers on the subject, and came to the conclusion that the Inflexible was not a safe ship for battle, and that the objections brought against her had been much too lightly treated. Now that the Report of the Admiralty Committee is before us we are able — not- withstanding much that appears in it — to point our readers to it as a full and complete justification of the course we and others then pursued, for that Report con- cludes with these words : — '"' We therefore desire to bring under the very serious consideration of their Lordships the necessity, before proceeding with the construction of more vessels of the type of the Inflexible, of thoroughly investigating whether by more beam their safety may not be largely increased without impairing their speed and efficiency." As this appeal "to the very serious con- sideration of their Lordship's " in arrest of the construc- tion of other ships of the type closely follows a paragraph in which the Committee show the very great advantages of an alteration in the form and proportions of the Inflexible s citadel (without increase of armour), it is not conceivable that the Board of Admiralty will proceed with the other vessels of the type, and it is absolutely certain that no more ships possessing the defects of which we complained in July will be laid down. The great object which we set before ourselves, therefore, is already accomplished, and the extension of a dangerous system of design throughout our own navy, and the navies of the world, has been effectually arrested. As we know that the case of the Ajax and Agamemnon was actually before the Committee, and as their Report makes no exception of them in their appeal to the Admiralty to stop further proceedings, it is to be inferred, we presume, that the beam of these two ships will have to be increased in accordance with the Committee's views. With these results before them all those who took part in bringing about this inquiry may, we think, be congratulated on the success and value of their labours. There only remains the Inflexible herself to consider in the light of the Committee's Report ; and in discussing this part of the subject we must not forget that no incon- siderable portion of the report, and especially the aspect which its opening pages presents, has been greatly in- fluenced by the form of the Admiralty reference. We take leave to say that the first of the questions put by the Admiralty to the Committee has little or nothing to do with the subject. We do not remember that even Mr. Reed, who has most strongly condemned the Inflexible's design ever contended that " the blowing out of the whole of the stores and cork by shell-fire " would occur very early in an engagement ; and if he had, the elicitation of Vol, XVII.— No. 425 a contrary opinion from the Committee would have no serious bearing upon the subject, simply because experi- ment, and experiment alone, can determine the degree and rapidity of the injury to which thin iron chambers filled with cork are liable. Mere opinions, in the absence of experiments, are comparatively valueless in such a case. But what we should have thought was absolutely self-evident, even without any experiment, is that shell- fire from modern ordnance would certainly blow cork packing out of thin iron chambers at some rate or other ; and yet, strange to say, this is what the Committee appear to doubt, and even to deny, for they say that in their opinion that which may "ht fairly assumed to represent the greatest amount of damage the ship would be likely to suffer in any action " is the condition in which, although the unprotected ends are completely riddled and water- logged, the cork and stores remain in place, and add to the buoyancy. It is fair to assume, then, according to the Committee, that in no naval action will the cork be blown out of place by shell-fire, and this in face of the fact that when an experiment was actually tried at Ports- mouth the contrary result was experienced. It is of the utmost importance to note carefully that it is only by making the above extraordinary assumption — an assump- tion which we believe will not meet with the concurrence of scientific artillerists and seamen— that the Committee are able to oppose in any degree the opinions of the ship's danger which we and others expressed in the autumn. It is on this assumption that they rest their opinion that '' the unprotected ends are as well able as the armoured citadel to bear the part assigned to them," and that therefore " a just balance has been maintained in the design." It unfortunately is made perfectly clear afterwards by the Committee that the " part assigned to them " is to hold the citadel and the rest of the ship upright, and it is clear that they cannot be presumed fit to perform this part if shell-fire can blow out the cork This is the weak point — we venture to think the danger- ously and even fatally weak point — of the Committee's Report, and one which the common sense and observa- tion of men will prevent them from assenting to, and consequently the Inflexible's safety is so ill-assured that we doubt if responsible persons will sanction the com- pletion of such a ship. The committee have fallen, as it appears to us, into a grave inconsistency, likewise, as regards the Inflexible herself. They say, as we have seen, that the unprotected ends are, as designed, well able to perform their part, and well balanced with the citadel. In subsequent passages, nevertheless, they go on to disclose and assert even more serious defects in them than any of us adverse critics of the ship have alleged, and to recommend an enormous extension of the cork chambers. What is the meaning of a scientific committee dealing with an extremely grave public question in this way? Either the unarmoured ends are well designed at present, or they are not ; if they are, why alter them to the very large extent — far larger than a cursory perusal of the report might lead readers to expect, for the increase of cork chambers recommended is enormous .'' If they are not, why has the contrary statement been made and circulated ? The truth is tkey have not been satisfactorily designed, as we shall presently prove from the Committee's own report. But first let us I 138 NATURE {Dec. 20, 1877 dispose of a long argument which the Committee enters upon and pursues with the object of proving that by- lengthening the citadel you would thin the armour upon it, and thus reduce its defensive power. Assuredly you would : nor can any one doubt for a single moment that it would be far better to reduce the armour a little for the purpose of making the citadel stable enough to hold the ship upright in spite of any injury to the unpro- tected ends, rather than to keep the present thickness, and to reduce its length sufficiently to cause the whole to capsize when the unarmoured ends only are badly damaged. We know how naval officers answer this question. But, in truth, the whole argument of the Committee on this point is beside the mark, and a mere beating of the air, for no one that we know of has urged the change which the Committee take so much pains to discuss. What we have always understood Mr. Reed to allege, and certainly what we have in Nature maintained is, that in the Inflexible the citadel and unarmoured ends were neither well- formed, well-proportioned, nor well-balanced against each other, and that a ship of her type should have em- braced a larger area of flotation within the citadel and a less area within the unarmoured ends. And this is pre- cisely what the Committee themselves declare, and thus refute their own assertion that the ship is properly designed at present. Near the end of the Report they say : — " Results which have been obtained in the course of the experiments at Torquay on the resistance of ships, show that a considerable increase of the extreme breadth of the Inflexible, if accompanied by a corresponding fining of the ends so as to keep the displacement unaltered, would, if anything, diminish the resistance of the intact vessel to propulsion at full speed. Supposing the ship thus increased in beam 10 feet, and the citadel shortened so as to retain the same perimeter and thickness of armour, her transverse stability would then be about doubled in the e and/' conditions, and in the riddled and gutted condition, would be more than it now is in condi- tion e or/. Her longitudinal stability in the riddled and gutted condition would be reduced 10 per cent. (/, Appendix No. 15), but would not be diminished in condi- tion e, and scarcely appreciably so in / The increase of beam would also add to the area of the citadel in a hori- zontal plane, and thus increase the buoyancy in the riddled condition." When the Committee, who lay^down these clear and cogent proofs that the Inflexible is vastly inferior, in respect of stability and safety, to what she might have been, also tell us that " a just balance has been main- tained in the design " of that ship, and that " a good result has been obtained," we find great difficulty in reconciling their statements, and feel strongly that if the public were to trust only to the language of the Report they might readily be led to draw extremely wrong infer- ences. We much fear that the gentlemen composing the Committee have thought too much of the Admiralty, with which they are all more or less connected, and too little of the public, who have been waiting for many months for their verdict. That verdict has been pronounced in a manner which, speaking 'on behalf of scientific men, we lament. It is inconsistent, and, so far as we can under- stand it, contradictory, in its several parts, and is in large ^ These references caud/, are to the Parliamentary Papers, and represent the ship with the ends riddled and water logged, e, showing the coal as well as the cork, &c, in place, and /with the cork, &c., in, but not tiie coal. part likely to beget in certain quarters a fatal confidence in a ship the defects and dangers of which the Committee evidently well understand. So uncertain and indefinite is it that it does not make it unquestionably clear even that the Ajax and Agamemnon are included in their desire to have progress arrested, for although after speaking of the Inflexible only they ask that no more vessels of the type may be proceeded with, and thus employ terms which cannot well be otherwise interpreted ; the absence of all mention of their names nevertheless leaves room for the suggestion of a doubt on the point. It was clearly due to all concerned that their views on so weighty a matter should have been placed beyond all hesitation and question. But those who would understand the full significance of this Report must not be deterred from perusing it care- fully through, for if after reading thirteen out of its sixteen pages they Avere to throw it aside they would have derived from it, we say without hesitation, not only a very insuffi- cient but a very untrue conception of the hflexiblds actual condition. Up to that point both a hasty and a deliberate perusal of it yields, to our minds at least, the impression that the Committee are admirers of the exist- ing ship in almost every particular. But the disclosures which the scientific conscience of the Committee de- manded and enforced commence on p. 14, and thence to the end facts of an appalling nature respecting her are gradually unfolded with so much effect that even the Committee themselves end by imploring the Admiralty not to repeat such a design ! Let us briefly observe what these disclosures are. The first relates to the inclining force which the action of the rudder exerts upon a ship of small stability. The Committee made experiments with the Thunderer ex- pressly to acquire facts illustrative of the Inflexible's case, and the conclusion at which they arrived is thus stated : — *' The Inflexible riddled and gutted,^ and without water ballast, going at 7*24 knots, and turning in the circle of 1,210 feet in diameter, would require a righting lever or G Z of '13 feet, and as the value of GZ at her maximum stability in this condition is only '12 feet, she would on this supposition overset." To soften down this alarming fact the Committee add : " It is, however, not to be expected that the ship under this condition could be driven at this speed"— a speed of y\ knots only round the circle, corre- sponding to only eleven knots in the Thunderer when steaming on a straight course ! And this the reader will bear in mind is true of the iTflexible, not when her armour has been pierced by huge shells, or her bottom knocked about by rams and torpedoes, but when nothing but her exposed unarmoured ends have been badly injured. Her armour and her bottom may be perfectly intact, ay, untouched, and yet her own rudder would capsize her in steaming at a low speed. No statement ever made about the Inflexible by those who condemn her has gone or ever could go much beyond this. And what can be thought of the figures given ? The line GZ is the lever or arm, at the ends of which the gravity and buoyancy of the ship act in opposite directions. The length required for withstanding the rudder's action under I This phrase, "The Inflexibli riddled and gutted"" is (improperly) employed by the Committee when they speak of the unarmoured ends being riddled and having the cork blown out. Dec. 20, 1877] NATURE 139 the given conditions was '13 of a foot (ij inches only [!]), but even that is more than has been allowed in the design of this ship (viz. -12) in which the Committee say " a just balance " has been preserved.^ And this inability of the ship to withstand her own rudder's action, and that at a low speed, even with virgin armour and a bottom un- touched by ram or torpedo, having been asserted and urged by others, elicits no remonstrance or objection whatever from the Committee. And yet, when a little later on in their Report they have disclosed a somewhat similar degree of longitudinal instability — discovered, as they sup- pose by themselves^ but already well-known and obvious, doubtless, to others — and have shown that the ship would not be safe at seven and nine knots speeds because of her tendency to capsize lengthwise (so to speak), and so more or less down headforemost, then the Committee see grave danger showing itself, for they say, " We consider that any large limitation in the ship's speed may expose her dangerously to the attack of ram or torpedo," and in the summary they incidentally tell us, in the mildest terms, that a blow from either would be fatal ; " the small residuum of stability she would possess would not avail to render such an attack other than fatal." The only difference in the two cases is (and this is possibly the reason why the Committee lay the greater stress on this case) that it is not here necessary to suppose the cork or stores blown out, for a single shot or shell making a large wound near the stem, bulging a skin plate outwards, and completely rupturing the internal bulkheads, would so destroy the longitudinal stability of this large ironclad, costing more than half-a-million sterling, that even at seven knots' speed she would run her bows under ; " and again," we are told by the Committee, "her speed is similarly limited to nine knots by wounds of a much less critical character in other parts of her sides." We have said that even this danger was doubtless foreseen by others — as it certainly was by ourselves, whether men- tioned or not — before the Committee's Report appeared ; but the Committee certainly have carried the subject a step forward by the experiments they have made with the model, and by their positive declaration that " on the whole the effect of sea-waves must be to aggravate, and in some circumstances greatly to aggravate," this very serious and certain source of danger. In a word, the very Committee who have in another place asserted that in the Inflexible the balance is fairly maintained between the armoured and unarmoured ends, have elsewhere in their Report shown that that balance is so ill maintained between the two, that with all the cork in place one or two shot and shell penetrating the unarmoured parts would so reduce her stability that she could not be steamed ahead with any reasonable speed, but would of necessity become a prey to any ram or torpedo craft that might evade or disregard her guns ! Another disclosure of the Committee is that the mere running out of the guns " would become a serious element of danger as the ship approaches the riddled and gutted condition." Here again they employ the phrase to which we have already intimated an objection in a foot-note, and speak of " the ship " approaching " the riddled and ' The Committee, at the bottom of page 15, give us the means of readily illustrating the amount of stability whicJi the InJIexibU has tin the case above considered, for they tell us that 60 tons in the bottom of the ship, which herself weighs over 11,000 tons, would alter the length of cz to '12 of a foot. gutted condition." They mean nothing of the kind ; by "the ship" they mean the exposed unarmoured ends only ; and here again it is to be observed that the danger disclosed is not one contingent upon the blowing out of all the cork, &c., but arises before, when the unarmoured part only approaches that condition. That the danger is, again in this case as in the previous one, a very serious and practical one is shown by the Committee recom- mending an alteration in the gunnery arrangements, proposing that the travel of the gun on the slides should be restricted, lest by running the guns out to the full extent at present arranged for, they should capsize the ship. We have now sketched, sufficiently for our present purpose, the substance of the Committee's Report. We may end this article as we ended that of July 19, and repeat : " The conclusions we have arrived at are, that the Inflexible is not a safe ship for battle in her present state, that the objections brought against her have been much too lightly treated, and that the disclosure of her condition, with the circumstances that have followed it, have excited just surprise and dissatisfaction." That surprise and dissatisfaction will be greater than ever when the Committee's Report has had time to produce its full effects, both intended and unintended, HYDROPHOBIA 1 II. WE do not intend to do more than allude in a cursory manner to the prophylactic treatment of hydro- phobia, i.e. to the treatment adopted to prevent the occur- rence of the disease in those who have been bitten by mad dogs. The general experience of the past sanctions, as might be expected, the practice of attempting to prevent the absorption of the poison of rabies by excising or destroying by caustics the wounds inflicted by rabid animals ; of the innumerable internal remedies which have been proposed and made use of with the object of preventing the deve- lopment of hydrophobia in those bitten by rabid dogs, it may be said with justice that nothing whatever is known which warrants the assertions of their advocates. This is indeed a case in which the fallacies which beset all therapeutical inquiries, especially when attempted by ignorant persons and fanatics, are specially liable to obscure the truth. Of all dogs supposed to be rabid, only an infinitesimal proportion really are so, and it is but rarely that the fact of a dog being rabid is tested by having it watched until it dies, or by the unfortunate fact that some of those bitten perish by hydrophobia ; then, of all persons bitten by certainly rabid dogs, only a small proportion become affected with hydrophobia, even when no treatment is adopted, so that the value of any drug or remedial measure as a prophylactic could only be tested by an experience such as no one ever has had. Less uncertainty prevails in reference to the effects of treatment when hydrophobia has been developed. According to the best observers this disease has hitherto been invariably fatal. There are, it is true, a few cases — and of these two have been recorded within a compara- tively recent period— in which a cure is said to have been effected, but when examined with care the'gravest doubts > Continued from p 119. 140 NATURE {Dec. 20, 1877 of their real nature must be entertained. Here again there are fallacies to be encountered of no insignificant nature. The continued and terrible anxiety lest a bite which has been inflicted should be followed by its terrible consequences has led, in the case of persons of a susceptible and unstable nervous system — as all other long- continued worries and anxieties are liable to do— to the development of hysteria and insanity and, in the attacks of acute mania which have occurred in such indi- viduals, many of the phenomena of hydrophobia have been imitated. An admirably-narrated case of this " hydro- phobic non rabique " of French writers was lately placed on record by Mr. Hugh Norris, of South Petherton (" Hydrophobia or its Eikon— which ?" — Lancet, Septem- ber 22, 1877) : — "A gentleman underwent terrible anxiety on account of his young son having been bitten by a dog which suddenly had become ill and strange in its behaviour. The danger which threatened the boy caused the father to become intensely emotional, and prolonged sleeplessness ensued. Other worries superadded them- selves to this one great gnawing anxiety, and the poor man fell ill ; at first there appeared symptoms which simulated very closely the hydrophobic phenomena, but these were succeeded by a genuine attack of acute mania, which necessitated the^patient's removal to an asylum, where he died on the seventh day of his illness." In this case there was no evidence that the patient was actually bitten by a dog, his statement that he had been so injured having been made, in a peculiarly suspicious manner, only after his illness had commenced, and being apparently but one of the delusions' which afterwards haunted him. Had this man been certainly bitten, and had his illness been followed, as it might have been, by recovery, his case would in all probability have been quoted as one of the few instances of recovery from hydro- phobia, though the impartial critic would have pointed out some anomalies which rendered the conclusion doubtful. The knowledge of the undoubted occurrence of such cases necessarily imposes great caution in the examination of alleged instances of recovery from hydro- phobia. The drug to which attention has of late been directed for the treatment of hydrophobia is curare or woorara, a substance used by the natives of South America as an arrow poison. This poison has been known since the end of the sixteenth century, when Sir Walter Raleigh made the conquest of Guinea ; but attention was drawn to it in a special manner by the celebrated traveller, Waterton, who first made experiments on animals with it, which were continued by Sir Benjamin Brodie and Dr. Sibson, and were succeeded by the now celebrated researches of Claude Bernard, Kolliker, and other eminent physiologists. Curare, the active principle of which is derived from a strychniaceous plant, when directly introduced into the blood or injected under the skin, produces paralysis of all voluntary movements ; this paralysis depends upon 'ts exerting a special action upon the terminations of motor nerves in the muscles, especially in voluntary muscles. The poison leaves intact the sensory nerves of the body, and at least in the early stages of its action, the nerve- centres. An animal subjected to its influence becomes absolutely motionless, and dies rapidly of suffocation from paralysis of the respiratory muscles ; if, however, respiration be kept up by artificial means, life may be prolonged for long periods, and, the poison becoming eliminated, recovery may ensue. As long, however, as the stage of complete paralysis continues, the creature is entirely unable to communicate with the external world. There is no proof that external stimuli do not affect it ; that it does not feel— but the channels by which the evi- dence of sensibility reach us are for the time interrupted. Curare has been suggested as a remedy for many diseases of a spasmodic character, but a great obstacle to its use is presented by the danger which attends its employment. A dose which will be sufficient to arrest an abnormal spasmodic contraction of a muscle or group of muscles, will presumably cause a stoppage of respiratory move- ments, and the medical man, if haply he be near the patient, will find himself compelled to keep up artificial respir?vtion — no easy task to accomplish, especially with the means which the physician, as distinguished from the physiologist, could employ. Hitherto the attempts to use curare have been few, and the results (if we except the two supposed cases of cure of hydrophobia) we think worthless. Curare is indeed a drug the employment of which must be attended with so great a risk that a very strong case should be made out in its favour before patients are exposed to it. Knowing as we do the physiological action of curare, we may ask whether it is a drug at all likely to be ser- viceable in spasmodic aff"ections generally, and specially in hydrophobia. The majority of spasmodic diseases are due to a central cause, or to a cause acting through a preternaturally excitable centre. Any drug which will cut off" — as curare does— the communication between the nerve-centre and the muscle will prevent its spasm, and will of course obviate any evil results which follow directly from the spasm ; but, necessarily, under these circumstances the abolition of the spasm is no index that any change has been effected in the morbid state to which it owed its existence. In hydrophobia there occur, it is true, as prominent phenomena, spasms of the muscles concerned in inspiration and in deglutition. The administration of curare in doses sufficient to stop the respiratory move- ments would doubtless prevent these spasms, though we must not forget that it would do so at no mean risk. But are these spasms the proximate or remote cause of death in hydrophobia ? We believe not. They are spasms which, as we tried to show, are probably dependent upon a morbid state of the medulla oblongata, with which is connected a morbidly heightened reflex excitability of that portion of the nervous system. But there is no evidence that curare would exert any influence in dimin- ishing this abnormal excitability. From our knowledge of the physiological action of curare we should not then be inclined to believe that it could affect in a beneficial manner the progress of the essential morbid processes of hydrophobia ; it could but modify some of the painful phenomena which belong to it. Actually curare has been tried in several cases, but only twice has its administration said to have been attended with success, and these two cases cannot be accepted as having been certainly cases of hydrophobia. We have seen one case of hydrophobia treated with curare without any influence having been exercised by it. There are drugs, however, which the physician is habitu- Dec. 20, 1877] NATURE 141 ally employing that possess actions which would cause one to predict that they would be of special use in controlling the terrible spasms of hydrophobia, e.g.^ bromide of potassium, chloral, and Calabar bean. These drugs all diminish in a signal manner the reflex ex- citability of the nerve-centres ; and the second in the list possesses in addition powerful properties as a hypnotic ; they have all been used in the treatment of hydrophobia ; and one of them — chloral — has, in sufficiently large doses, been successfully used, in so far as relief of suffering was concerned. But as for a cm-e for hydrophobia it has yet to be discovered ; and this remark applies to all zymotic diseases. The majority of these diseases, unlike hydrophobia, tend naturally towards recovery rather than death, and the physician is undoubtedly able, by judicious measures, to obviate the tendency to death. He cannot cure the disease, however, in the sense in which he might be said to cure it were he able to destroy the poison which is its cause ; apparently, once introduced into the system the poison must produce its effects — intense or slight — which must have a certain course, and then cease, be- cause the poison which induced them has passed away, or because the soil which nourished the poison supplies it no longer with the conditions which it required. But the day may come, and we believe will come, when even this great result may be achieved ; when not only shall we know the conditions which attend the spread of zymotic diseases so accurately that we shall be able to prevent their spread, but when medicine may supply us the means of dealing directly with the materies morbi of the diseases, as, for instance, by "sterilising" the soil in which they are implanted. Oar general review of the main facts in the history of rabies and hydrophobia has naturally brought out with considerable clearness how little is known concerning it and how much remains to be done. We hail, therefore, with satisfaction the appointment of a Committee of the British Medical Association charged with the investigation of this important and interesting subject. This Committee consists of Dr. Lauder Brunton, Mr. Callender, Mr. Ernest Hart, and Prof. Burdon-Sanderson. Before concluding, a few words concerning the measures to be adopted for preventing the spread of hydrophobia. From our insular position we are in a better position than any neighbouring nation for holding a check, or even " stamping out " such a disease as hydrophobia, which, as the vast mass of evidence tends to show, does not originate spontaneously, nor does it appear that it would be difficult to effect this result were the suggestions which have been made by several recent writers carried into effect. It is certain that the number of dogs kept in England is enormously in excess of any requirements, and it is equally certain that this state of matters might promptly be put a stop to. The existing dog tax need not be increased in amount, but it should be enforced in the most stringent manner, the business of collecting, prose- cuting, &c, being handed over to the police authorities of each district. Each dog should have a separate number on the local register, and might be the wearer of a collar bearing its registered number. Further, the licence should bear a description of the premonitory symptoms of rabies, and owners of dogs should be cautioned instantly to report any suspicious case to the police. These regulations would, as a necessary result, lead to each dog being indi- vidually looked after and cared for, and would, we believe, in the course of very few years, lead to the disappearance of rabies. DIEN'S " CELESTIAL A TLAS " Atlas Celeste, comprenant tontes les Cartes dc I'ancien Atlas de Ch. Dien. Rectifid, augment^, &c., par Camille Flammarion. 3" Edition. (Paris : Gautbier-Villars, 1877.) THIS is a new and enlarged edition of Dien's "Atlas Celeste," which first appeared in 1864, with the co-operation of M. Babinet, and is brought out under the editorship of M. Camille Flammarion. That the forma- tion of the atlas, both in its original and extended plan has involved a great amount of labour will be evident upon a very superficial examination. The first issue was said to contain upwards of 100,000 stars and nebulae, of which 50,000 had been observed by Lalande, projected on the development of a sphere, sixty-five centimetres in diameter, their places being reduced to the year i860, and this scale was stated to be sufficiently large to allow of the insertion without confusion of all stars to the ninth magnitude inclusive. The charts were said to contain " nearly jthe totality of stars in the catalogues of Lalande, Herschel I., Piazzi, Harding, Struve, Bessel, Herschelll., Groombridge, and Argelander," while for the southern heavens recourse was had to the catalogues of La Caille and Brisbane. This description of the authorities con- sulted is not very definite. The reference to Harding must apply to his atlas ; that to Bessel may be supposed to at least include the catalogue of equatorial stars ob- served by the Konigsberg astronomer, which was prepared by Weisse of Cracow, and pubHshed in 1846, if not the second catalogue founded upon Bessel's observations, containing stars from 15° N. to 45° N. decUnation, also reduced by Weisse, which appeared in 1863. The refer- ence to Argelander is especially indefinite ; we have the well-known catalogue of 560 stars, and the " Uranomelria Nova," but previous to the year 1864, when "Dien's Atlas" was published, astronomers were also in posses- sion of vols. 3, 4, and 5 of the " Durchmusterung," with the results of the survey of the whole northern heaven'^. The programme originally prepared was a very exten- sive one. The new edition is stated to have received numerous corrections and considerable enlargement to bring up the work to the actual state of astronomical science, and there is sufficient evidence that an attempt has been made in this direction, but we regret to have to express the opinion, after a close examination of the " Atlas," that in its present state it does not fulfil the pro- gramme upon which it was formed. It will soon be evi- dent, on comparing the maps with the charts issued by the Berlin Academy, or more generally with those in the original edition of Harding's Atlas, that so far from con- taining stars to the ninth magnitude inclusive, numerous eighths, and even stars of 67 magnitude, are omitted, and it is not easy to see from what cause. It might be inferred that Bessel's catalogue of equatorial stars had not been utilised, since stars of the seventh and eighth magnitude observed by Bessel and not observed by Lalande, are wanting. But in addition we soon miss stars that do occur in the " Histoire Cdleste," as for 142 NATURE {Dec. 20, 1877 instance L. 39836, a star which Lalande considered a sixth magnitude. Different views will be taken with regard to the proper contents of a celestial atlas, intended for general use, and it is not nerefore desirable to be too critical upon this point, but to take, we will say, two'extreme uses to which an atlas of the pretensions of Dien's may be applied, first for following a small planet with the aid of a chart pro- fessing to contain stars to a less degree of brightness, and secondly, for identifying the naked-eye stars by the general maps including only these brighter stars, an elementary purpose for which an atlas may be quite as readily adapted as a globe. In the former case Dien's maps are not sufficiently filled in to allow of a planet equaUing in brightness stars of Bessel's ninth magnitude being identified without some trouble and disappointment, and in the latter case we meet with a failing which is only too common with star- atlases — the outlines of constella- tions are so prominently drawn as seriously to interfere with, if not entirely to obliterate the naked-eye stars of the lower magnitudes, in using the " Atlas " in the open air. As a model of what an atlas should be in the latter respect, we must still refer to Argelander's " Uranometria," which, in our opinion, has yet no equal for the more elementary uses of such a work. Among the best features in the new edition of Dien's " Atlas " are the delineation of the southern heavens, in which Brisbane's stars are laid down, the view of the dis- tribution of double and multiple stars by M. Flammarion, the orbits of some of the principle revolving double-stars, and figures of remarkable nebulae and clusters of stars, OUR BOOK SHELF Horticulture. By F. W. Burbidge. With Illustrations. (London: E. Stanford, 1877.) This is one of the series of small handbooks on the British maufacturing industries, edited by Mr. G. Phillips Bev;\n, of which we have already noticed several volumes, A compact work on practical gardening, to serve as a guide to the amateur gardener and fruit-grower, was much wanted, and this volume to a certain extent supplies the desideratum. After a short chapter on commercial garden- ing, the author treats of the cultivation of fruit, and of the various descriptions of vegetables and herbs ; and then of gardening in its various departments, but more from the economical than from the amateui^'s point of view. If the owner of a garden wants to turn his bit of land to the most profitable account, he will find Mr, Burbidge an admirable guide ; but if he infers from the title of the book that he will obtain from it advice as to the treatment of his pelargoniums, fuchsias, and chrysanthemums, or the management of his hothouses, he will be disappointed. We fancy that information of this kind would commend itself to a larger number of readers than the guide-book information of the exact number of acres in each of our London parks, and the annual cost of maintaining them. The advice as to the culture of fruit and vegetables seems to us very good ; but the rather poor woodcuts do not add to the value of the volume. Mittheilungen aus dem k. zoologischen Museum su Dresden. Herausgegeben mit Unterstiitzung der Gene- ral-direction der koniglichen Sammlungen fiir Kunst nnd Wissenschaft, von Dr, A, B, Meyer, Director des konighcben zoologischen Museums. Zweites Heft mit Tafel. (Dresden, 1877.) In a former volume of Nature (vol. xiii.,p. 464) we have given some account of the origin of this meritorious work, of which the second portion is now before us. Like the former half of the first volume of the contributions the present section is chiefly occupied with memoirs based upon the collections made by Dr, A, B. Meyer during his well- known expedition to New Guinea and the adjacent islands. Herr Th, Kirsch, the entomologist of the Dresden Mu- seum, commences with two articles upon the lepidoptera and beetles collected by Dr. Meyer in New Guinea. Of the former Herr Kirsch enumerates 167 species, of which 133 belong to the diurnal section. Several novelties are described and well figured. The next article is by Dr. Meyer himself, and gives us an account of a large series of Papuan skulls which he collected on the mainland of New Guinea and in the Island of Mysore, in the Bay of Geeldink. The collection, embracing altogether 135 examples, is, we believe, by far the finest of this branch of the human family ever made, and should, we suppose, lead to some definite results upon that somewhat mysterious subject — the differentiation of the various races of mankind by their skulls. A second article by Dr. Meyer relates to the speci- mens of anthropoid apes in the Dresden Museum. We cannot say that the photographic plates of the stuffed speci- mens of these creatures are either elegant or likely to be of very great use, butitis.'satisfactory tohave the vexed ques- tion of the identity of the celebrated '"' Mafoka " lately living in the Zoological Gardens at Dresden, and long supposed to be a gorilla, finally set at rest, as is done by von Bischoff's article on its anatomy, which follows that of Dr. Meyer. A memoir on the Hexactinellid Sponges collected by Dr. Meyer in the Philippine Seas, in the preparation of which Herr W. Marshall has given his assistance, concludes this interesting volume, of which we may say that it adds materially to the status of the Dresden Museum, and to the scientific fame of its energetic director. LETTERS TO THE EDITOR [The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts. No notice is taken of anonymous communications. The Eddor urgently requests correspondents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of com- munications containing interesting atui novel facts. ^ The Radiometer and its Lessons I AM obliged to ask you to allow me to add a few words, by way of further explanation, to my letter printed in Nature, vol. xvii. p. 80. In trying to estimate the effect of the communication of heat between a solid body and contiguous gas, I have assumed that certain simplifying suppositions may be legitimately made, for the most patt identical with what are very commonly adopted in discussing the pressure exerted by a gas on a solid in contact with it. That is to say, I have assumed, first, that we may resolve the velocities of the mjlecules of gas into three rectangu- lar components, one perpendicular to the surface of the soiid and the other two parallel to it ; second, that we may conceive of the who!e number of molecules as divided into three equal parts, one- third moving in the direction of each of the resolved components of the velocity respectively ; third, that the mutual pressure between the solid and the gas, and any communication of heat from one to the other, may, for the purpose in hand, be attributed to direct impacts of molecules against the solid surface ; fourth, that all the molecules endowed with a velocity perpendicular to the solid surface, and con- tained within a layer adjacent to this suiface of a thickness not greater than the mean length of path, will strike the surface, while none of those which are outside this layer will ever reach it ; fifth, that the particles which have struck the solid surface will return from it with an average velocity corresponding to the temperature of the surface, and will retain this velocity until they arrive at the farther side of the layer before- mentioned. It was on the supposition that these are legitimate assumptions that Dec, 20, 1877] NATURE H3 I spoke of heat passing across a stratum of gas from one solid surface to another " as though there were, in contact with each solid surface, a layer of gas whose temperature is throughout the same as [it would perhaps have been been better to have said "determined by "] that of the contiguous solid." I am fully aware of the ease with which one may be led into serious mistakes by trusting too implicity to such simplifying assumptions, and also that some of the particular suppositions made above would be inadmissible in a discussion of the general problem of the conduction of heat in gases ; but I do not see any fallacy in employing them for the special purpose which I had in view in my last letter, namely, to show why I think that the flow of heat across a thin stratum of gas must be facilitated by dimi- nishing the pressure of the gas. Prof. Osborne Reynolds's argu- ment that " if there were a layer of uniform temperature, no heat would be transmitted," does not appear to me to be applicable to the case in question. It seems conceivable, as an extreme case, that, in a very thin layer of gas, between parallel solid surfaces maintained at different temperatures, the molecular movements might take place exclusively in the direction of the perpendicular to the bounding surfaces. In such a case the particles would move from side to side of the layer of gas with a uniform velocity, though the velocity one way would be greater than the velocity the other way, and heat would be transmitted across a layer of gas having the same temperature throughout. Such a condition, whether practically realisable or not, would, if I understand him aright, be the limiting case in one direction of what Mr. Stoney has called for shortness a " Crookes's layer : " the limiting case in the other direction being the ordi- nary condition of a gas, where the average velocity of the molecules is independent of direction. I venture to think that, in pointing out the results which must follow from the existence of a predominating direction of molecular motion, Mr. Stoney has made a very important contribution to the kinetic theory of gases ; and I do not see that his conclusions are in any way invalidated by its being shown that they are not in harmony with " the generally-accep'ed laws of gases," inasmuch as these Uws are deduced from suppositions which expressly exclude the conditions he has investigated. G. Carey Foster December 17 Allow me to say a few words on what I believe to be the correct theory of the radiometer. This theory was given to me by Prof. Osborne Reynolds during spring of 1875, and I have found it capable of explaining every experiment on the subject with which I am acquainted. The conservation of momentum is one of the laws of nature which even molecules do not break, and that law puts some restraints on the wonderful things ^yhich the shocks of molecules can accomplish. Imagine a vessel full of gas at a certain tem- perature. The centre of gravity of the gas and that of the vessel are supposed to be at relative rest. Suppose now that I increase the velocity of a certain number of molecules in a given direction, the centre of gravity of the gas will move relatively to the centre of gravity of the vessel, and no number of encounters between the molecules can alter that motion until the momentum has been taken up by the vessel. If in any gas we have a passage of heat in a certain direction, we shall have a propagation of momentum owing to the fact that the molecules move more quickly in one direction than in the opposite one, and no number of encounters can alter that propagation. Where the momentum enters the gas and where it leaves it we observe certain forces. This is Prof, Reynolds's theory of the radiometer. It has been objected that an increased pressure on the cool side of the vanes of a radiometer will counterbalance the force acting on the blackened sides, when the dimensions of the vessel are large compared with the mean path of a molecule, but I do not think that such is the case. The following special case may make this point a little clearer. If the forces on the vanes are counterbalanced, the forces on the vessel must be counter- balanced as well. In the case of an ordinary radiometer the forces reduce to a couple, and I do not see how any crowding of molecules in one part of the vessel more than in another can produce a couple on the vessel. The whole problem is one of conduction of heat. All the experiments made by Mr. Crookes on cups, inclined vanes, &c., admit of the same easy explanation as the fact that when a long and a short wire are connected with the poles of a battery, the current in the shorter wire will be the strongest. In a radiometer with inclined vanes, for instance, the temperature is the same on both sides, but the gradient of tem- perature is much larger on one side, and hence more heat will escape on that side. The dimensions of the vessel also have to be taken into account in the same way as the length of a wire has to be taken into account when the strength of an electric current flowing through it has to be calculated. It is difficult to say exactly what takes place within very small distances from the hot surface, but it seems clear that any phenomenon, such as Prof. Carey Foster supposes to exist, must affect the passage of heat in the same way as the force on the vanes. As the careful researches of Messrs. Kundt and Warburg have shown that under great exhaustion the conduction of heat decreases and does not increase, I do not see how an increase in the force can take place. The scientific world will judge how far Prof. Stoney has suc- ceeded in establishing'any new laws on the conduction of heat through gases. In justice, however, to Messrs. Provostaye and Dessains, whose experiments he calls to his aid, I wish to point out that their numerous experiments, with two exceptions, are in entire accordance with existing theories. At the time these experi- ments were made, no distinction was drawn between convection and true conduction. In order to deduce, therefore, the loss of heat due to true conduction, Prof. Stoney is obliged to subtract the effect due to convection currents. He draws, therefore, a curve representing the loss of heat due to this cause. All his conclusions must stand or fall with this curve, and I am afraid they must fall. After Professors Clausius and Maxwell had deduced theoreti- cally the coefficient of conductivity for gases, a series of cele- brated experiments were made by Stefan, by Narr, by Plank, by Winkelmann, and last, but not least, by Kundt and Warburg. The influence of convection currents has been fully discussedjin these papers and eliminated, and the conclusions arrived at by all.these experimenters are fully in accordance with each other and with theory. It appears, as was expected, that when the effects of convection currents are eliminated, the coefficient of conduc- tivity is independent of pressure until the dimensions of the vessel are comparable with the mean free path of a molecule, and that then the conductivity rapidly diminishes. It also appears that at the pressures at which Messrs. Provostaye and Dessains found that the loss of heat was independent of pressure, convection currents must have ceased to be appreciable, and therefore the great mass of their experiments is fully in agreement with later researches. The only exception is found in the case of carbonic acid and nitrous oxide. These abnormal results were not confirmed by Messrs. Kundt and Warburg in the case of carbonic acid, the only one of the two gases which they examined. Whoever reads their account of the difficulty they had in excluding the last traces of moisture, and considers the increased conductivity which such an admixture would' produce as the pressure diminishes, will have no difficulty in explaining the anomaly. At any rate I do not think Prof. Stoney will be inclined to base important conclusions on unconfirmed experiments on two gases in which we should expect the effect, owing to their density, to be parti- cularly small. The discovery of Master Gerald Stoney, who found that a red hot wire was cooled when a tin can containing water was brought sufficiently close might, I think, have been foretold by the recognised theory. Prof. Stoney, no doubt, will find on reading over the literature on the subject, that what he calls penetration of heat, has hitherto been known under the name of conduction of heat, that it takes place at all pressures, and begins to disappear at the exact point at which he makes it appear. The timely calculation of Mr. S. T. Preston in the August number of the Phil. Mag., shows that any theory of the radio- meter which makes the action depend on the comparatively large ratio of the mean free path to the dimensions of the vessel, must necessarily be wrong. Arthur Schuster The Proposed Channel Islands' Zoological Station, Aquarium, and Piscicultural Institute I AM very anxious that this project ' should succeed, mainly because of the facilities it will afford to inland aquaria, in procuring living animals cheaper, better, more variedly, and more systematically, than at present. This, I believe, will form the most profitable part of the undertaking. « Referred to in Nature, vol. xvii. p. i«2. 144 NATURE [Dec. 20, 1877 I hope, also, it may succeed as a sort of living museum, with- out any of the kind of attractions which are not biological ones, and which, indeed, are not scientific in any sense, as common and ribald music, theatricals, acrobatic and jugglery performances, and so forth. Only, no aquarium has ever permanently thriven without these things, I greatly doubt whether anyone yet possesses the requisite knowledge to be able to rear any marine crustacean from the egg state to an adult condition, and to feed it in captivity in such manner as to be able to sell it in the open market at rates below those sold under present circumstances. Yet this is put forward, conspicuously, as one of the aims of the scheme. In Britain are eaten as human food about a dozen species of crabs, lobsters, prawns, and shrimps, and most of these have been occasionally bred in aquaria as far as the Zoea state, when they are free swimmers, and they then generally die. Rarely, some few have been brought up to a higher stage, but I know of no instance, during twenty-five years of experience, where any marine crus- tacean of any kind has been reared to an adult condition in an aquarium. And if such a thing could be done, I believe that to feed them in any state of captivity, with animal food, which they require in great abundance and variety, and which must be purchased, would be very expensive, indeed, far too costly I think, to be practically and commercially remunerative, I am glad to see that in last week's Nature, vol. xvii. p. 133, it is stated that that excellently-tasted httle fre^h-water lobster, Astacus, has been bred artificially by a Piscicultural Institution at Schwerin. If so, why should it not be similarly bred in Britain, where it is much seldomer eaten than in France and Germany. In Berlin, Hamburg, and Dresden, I have often purchased it at sixpence a Hozen, while in Paris I have given as much as sixpence each for it. I' is a pi'y. however, that the Schwerin account is not more full and explicit. It is stated that in the spring of 1876, 700 Astacus in e^g, were placed in two roundjponds, each of six feet diameter, H oles were made in these, and recently, on draining the ponds, only three or four adult crayfish were found straying about the ponds, the rest each being in a separate hole, and a large number of young ones were found, as big as bees, and very lively. What size were the crayfish at birth, and if very small, and swimming, how were they prevented from escaping from the ponds ? Information is wanted as to the shape, length, breadth, direction as to angle, and distance apart of these holes, and their position in the ponds, whether in the sides or ba^e, or both. If nearly 700 animals occupied as many holes, where were the young ones ? How many young were there? If each female had only as few as 100 eegs hatched out, then 70,700 must have been the popu- lation of these two little pools. When, and in what manner, were the males introduced ? We require also to be told of the material of which the ponds were constructed, and if the sides were upright, and the bottoms flat, or if rounded or basin-shaped. If water ran in and out, how much in a named time, of what quality, as to foreign substances it contained in solution and suspension, and what was its temperature at various periods of the year? In what direcion and in what amount was light admitted ? How much vegetation, and of what kinds, grew in the ponds? What kinds of animal food was given them, and how much and often, and was it cooked or raw ? Carrots appear an odd food for crayfish. Let all these things and more, be carefully ascertained, to see if they can be applied to the culture of ffomarus, the near marine relative of Astacus, before much money is spent. It would be an excellent thing for students to have a place to study at, such as is proposed to be provided for them at Jersey, and similar to the zoological station and aquarium at Naples, in the arrangement of which I had much to do. But would students be content to go only so far as Jersey ? Is not the access too easy, and too cheap, as it is not easy or cheap to go so far as Naples, and to have the name of so going ? I have often thought it odd, and evincing not at all a really zealous spirit in my own direction on the part of my fellow-naturalists, that such a thing should be, that though the Crystal Palace Aquarium has existed for seven years within less than one hour's railway ride from London, and though it contains a constantly advertised collection of living marine animals exceeded in variety and interest by none in Britain, or even Europe, yet no scientific man, except the late Edward Newman, has ever applied for permission to carry on any course of inquiry here on any subject, continuously or occasionally, connected with the habits of living creatures, in the spirit of say, Gilbert White of Selbome. Yet we ofifer all such advantages as table-space, good light, and the use of any animals in our tanks not having a considerable money value — lest injury be done to such specimens — absolutely free of all charges. At this moment we possess many Italian animals in our collection, as fishes, crustaceans, moUusks, zoophytes, &c., which can be seen aKve nowhere else, save on the shores of the Mediterranean, and yet no professed zoologist known to me ever comes to see them, or takes the smallest interest in them. They are therefore beheld only by the general public, who only look at them for their mere prettiness, or for what untrained observers are complacently pleased to term "ugliness." No student ever asks us for more than any dead animals we may chance to have, and which we give away gratis, and these apparently afford far more pleasure than the sight of living specimens. It is not at all uncommon to meet with biologists who openly and avowedly proclaim their contempt for collections of living animals in aquaria, which they regard as being "well enough for women and children," but for men they say there is nothing like seeing such animals in rows of glass jars of alcohol on the shelves of a museum. My last contribution of any length to Nature was made so long ago as October 12, 1871, when I gave a description of the Crystal Palace Aquarium, then only just opened. Since then we have had no cause to complain of the appreciation of the world of sightseers. But as regards the indifference of ihe scientific world, that has been and is so great that the place mi^ht never have existed. William Yarrell, the British ichthyologist of the generation just passed away, used to tell me how glad he would be to see a live John Dory {Zeus faber), and how much he would give to behold one swimming. But here, at Sydenham, this fish can be seen alive and in perfect health for months together, in crystalline sea-water. Yet no Yarrell ever comes to s^e them. Are there no Yarrells, and Whites, and Watertons, and Newmans now? or has their very spirit passed away into the region of apathy where the affectation of caring for nothing, and of being never moved to zeal in anything, in this observation of live animals, seems to be regarded as a very high accomplishment ? W. A. X,(.OYD Crystal Palace Aquarium, December 15 The "Challenger" Estimates' of the Volume of the Gulf Stream In the interesting " Voyage of the Challenger,''^ just published, Sir Wyville Thomson states (vol i, p 371) " thai the Gulf Stream in its restricted sense was, early in May, 1873, at the point where we crossed it and made our observation-, about sixty miles in width, 100 fathoms deep, and its rate three knots an hour." I was much surprised at reading this, as the Admiralty Report on Ocean Soundings, No. 7, p. 12, estimates it at the same point as " 100 fathoms deep, and running at the rate of three miles an houry2?r a -width of fifteen miles, discharging four and a half cubic miles of heated water per hour." As no reference is made by Sir Wyville Thomson to the extra- ordinary discrepancy in these two est mates of the same thing at the same time — one being four times the volume of the other — and as he says he makes the statement "thus guardedly" I think, in the interest of scientifie accuracy, an explanation is required, T. Mellard ReaDE Liverpool, December 8 The Fossil Peronospora as a Primordial Plant The concluding sentence of your notice (vol. xvii, p. 128) of my observations on a fossil fungus is so important, that I shall be glad of a word of reply. You say, "But should not this primordial plant have led a non-parasitic life ? for if parasitical, then this fact points to some pre-existing plant." Although the specimen I have figured is $hown as growing within the decayed tissues of a Lepidodendron, yet it does not follow that the same fungus could not perfect itself on humus alone. Recent species of Peronospora show a tendency to grow upon the ground, as several species, including the fungus of the potato disease, will grow and produce fruit on the naked earth, A truly terrestrial species is found in the allied Botrytis terrestris, Persoon, and many of the Mucedines grow freely in cellars, on damp walls, or in any moist place, < WORTHINGTON G. SMITH 15, Mildmay Grove, N, Dec. 20, 1877] NATURE 145 THE ''CHALLENGER" IN THE ATLANTIC^ n^HE Challenger left Portsmouth on December 21, -■• 1872, and on the evening of May 24, 1876, she dropped her anchor at Spithead afcer an eventful voyage, I which lasted three and a half years. Shortly after her arrival we gave a sketch of her cruise over the Atlantic and Pacific Oceans. The two volumes just published consist chiefly of an abstract of the less technical portions of the journal kept by Sir Wyville Thomson during the first year of the Challenger's voyage, and during the early part of the fourth yeat's voyage, when she was on her way home. During both these periods the Challenger was in the Atlantic, so that we now obtain the record of her survey of this great ocean in a very complete form, and are led to look forward to several additional volumes, in which the account of her cruise in the Pacific Ocean and amongst its fair islands wdl appear. A great deal of credit must be given to the author of these two splendidly illustrated volumes for his so speedily publishing them. A large portion of one of them was actually passed through the press while the Challenger was at sea, and the preparation of the second volume had to be carried on amid the cares not only of professional duties, but also of getting the immense col- lections made into order, and of making arrangements for the thorough working out of the scientific results of the voyage. May we express the hope that his energy will enable him speedily to complete the popular narrative of this cruise thus so auspiciously begun. The strictly scientific records of the Challenger voyage cannot be pubhshed for some time; the working out of old forms, the describing and illustrating of new ones, takes time ; such work, to be done well, must necessarily be done slowly, and hence we all the more urge on Sir Wyville Thomson to let us have, as soon as can be, the completion of the popular narrative of the general: resuhs of his four years' work. This preliminary account is mdeed not solely a popular one, for we find in these two volumes a mass of exact scientific details that will make them always works of reference to the scientific student ; and while some few of the wondrous new species of animals and plants are but incidentally introduced to us their descriptions are often so well written, and their forms are so exquisitely portrayed, as to leave us for the time somewhat independent of their more exact scientific diagnosis. In our previous sketch of the voyage of the Challenger we dwelt somewhat in detail on th-? work accomplished by her during the first six months of 1873. About the middle of June in that year she left the Bermudas for the Azores and Madeira, establishing twenty-five stations on her way, some of these showing ocean depths of 2,800 fathoms. A few pleasant days were spent (July 1873) at Ponta Delgada, the capital of San Miguel and the chief town of the A9ores. On acccount of the presence of an epidemic of small-pox no delay was made at Madeira, but the vessel's course was struck for the Canaries and Cape de Verde Islands, keeping somewhat parallel to the Coast of Africa until nearly opposite Cape Palmas, when they turned westward and shaped their course to Saint Paul's Rocks. These solitary rocks are nearly under the equator, midway between the coasts of Africa and of South America. They were visited in 1832 by the Beagle, and are noticed in Darwin's charmincr Voyage of a Naturalist." Merchant- vessels usually give them a wide berth. They seem to have struck the travellers by their small dimensions ; it being rather under J Z '^'T ^°^f ^o °^' ^"^ Ch^l^^'Ser. The At'antic : a Preliminary Account of the General Results of the Exploring Vojage of H M.S. CkallenZ- during the Year 187? and the Early Part of the Year 1876." Bv Sir'c Wyv.lle Ihomso.-,, Knt , LL.D.. F.R.SS. L. and E., &c., Regius Professo^ of Natural History in the University of Ediuburg", and Director of .he Uvihan Sc.en ific Staff of the Challenger Exploring Expedition. Two volum s. Published by Authority cf the Lords O^mims' oners of the Admirahy. (London: Macmillaa and Co., 1877.) "» 01 tfte a quarter of a mile from the one end of the group to the other, they form quite little specks of rocks out in mid- ocean. Landing on these rocks was no easy matter. A loop of eight or ten ply of whale-line was passed round one of the rocks ; to this a hawser was run from the ship lying about seventy yards out, with her bows in 104 fathom water ; the hawser was made fast to the whale-line, and the ship thus moored to the rocks. Having landed on the rocks a line was l.iid across the mouth of the cove, which made the landing easier for the next parties. Only two species of birds were found on the rocks, the '' booby" (^Sula fusca) and the " noddy " {Sterna stolida), both being widely distributed birds on tropical islands and shores. They were here in enormous numbers, were quite tame, even allowing themselves to be taken up with the hand. The bleeding season was over. No land plants were found, not even a lichen. The terns used a green alga to line their nests ; all the crannies of the rock were crowded with an amphibious crab {Grapsus strigosus), which was much more wary than the birds, though '' wherever a morsel of food came within their reach there was instantly a struggle for it among the foremost of them, and they ambled away with their prize wonderfully quickly : their singular sidelong gait and a look of human smartness about them had a kind of weirdness from its being exhibited through a set of organs totally different in aspect from those to which one usually looks for manifestations of intelligence." Leaving these desolate rocks on August 29, the island of Fernando Noronha was in sight on September i, rising like most of the ocean island?, abruptly from deep water, the depth of the ocean within six, miles of the island being more than 1,000 fathoms. This. island presents a most remarkable appearance ; the land is generally not very high, but there is an irregular cliff which rises to a height of about loo feet from the sea, succeeded by undu- lating land and conical hilts, usually covered with luxuriant vegetation. The Peak is an e;xtraordinary- looking mountain, formed of a column of rock which starts up to a height of 600 feet from a more or less level plateau of rock, itself some 400 feet above the sea. There is a village and a citadel, the place being a penal settlement belonging to Brazil. There were at the time on the island nearly 1,400 convicts and a garrisop 0/ 200 soldiers. The convicts enjoyed a considerable amount of liberty, each of them occupying a h.ut, and being allowed to cultivate a little piece of garden ground, though their time and labour from six in the morning until four in the evening belonged to the Governmenf. Sir Wyville Thomson and his assistants were extremely anxious to investigate thoroughly the flora and fauna of this island, but unfortunately the military commandant set his face against this, and the land work had to be abandoned, " The coast scenery was here and there very beautiful, little sandy bays with a steep cultivated slope above them, or a dense tangle of trees absolutely imbedded in one sheet of matted climbers, separated by bold headlands of basalt or trap stuff. Besides the tropic birds, there were to be seen beautiful little terns, snowy white, which usually flew in pairs a foot or two apart, one following all the motions of the other, like a pair of paper butterflies obedient to the fan of a Japanese juggler. They could be seen flying over the land, and often alighting upon the trees. The noddy was very common, and the booby wdi in considerable numbers. High upon the cliffs the nests cf the frigate bird {Tachy petes aquila) could be seen, and from time to time these splendid birds moved in slow and graceful circles overhead." No wonder that the author adds, " We lay for some time below the cliffs admiring the wonderful wealth of animal and vegetable life ere we returned slovly to the ship." On September 14, as they neared the coast of Brazil, a shower of buttei flies ft 11 on the ship, fluttering in multitudes over it ; and over the sea as far as the eye 146 NATURE \Pec. 20, 1877 could reach they quivered in the air. Looking up into the sky where they were thickest, they were seen to be close together and had much the appearance and peculiar motion of large flakes of snow. Amidst such a down- pour the entrance to Bahia was seen. It is very beautiful ; the coast is not elevated ; it is neither mountainous nor hilly, but rises fiom the sea-shore in even terraces, broken here and there by ravines and wooden knolls, every space gloriously clothed with vegetation, and the sky-line broken by long lines of palm trees — from the sea it reminded one of Lisbon, but its splendid luxuriance of vegetation gives it a character of its own. The scientific work of the Challefiger was to be on the ocean, and Sir W. Thomson properly discouraged his staff from expending too much of their time or energies on investigating the natural history of the few spots of North or South America that they from time to time landed on. We therefore in these volumes meet with very few references to the glimpses that they got of this continent, but some time had to be spent at Bahia, and we cannot avoid giving the following interesting extract which describes a visit made by Sir W. Thomson to Santo Amaro. " Mr. Wilson was obliged to be next day at Sto. Amaro, a little town about thirty miles distant, across one of the ridges on another river where he had a line of steamers plying, and he asked us to ride there with him ; so we went back to his house and dined, and spent the evening at his window inhaling the soft flower-perfumed air and gazing at the stars twinkling in their crystal dome of the deepest blue, and their travesties in a galaxy of fire-flies glittering and dancing over the flowers m the garden beneath us. It was late when we tossed ourselves down to take a short sleep, for two o'clock was the hour fixed to be in the Fig. I —The Challenger at St. Paul's Rocks. saddle in the morning. We rode out of the town in the starlight, Mr. Wilson, Capt. Maclear, and myself, with a native guide on a fast mule. We were now obliged to trust entirely to the instinct of our horses, for if a path were visible in the daylight there was certainly none in the dark, and we scrambled for a couple of hours right up the side of the ridge. When we reached the top we came out upon flat open ground with a little cultivation, bounded in front of us by the dark hne of dense forest. The night was almost absolutely silent, only now and then a peculiar shrill cry of some night-bird reached us from the woods. As we got into the skirt of the forest the morn- ing broke, but the rdveil in a Brazilian forest is wonder- fully diff^erent from the slow creeping on of the dawn of a summer morning at home, to the music of the thrushes answering one another's full rich notes from neighbouring thorn-trees. Suddenly a yellow light spreads upwards in the east, the stars quick'y fade, and the dark fringes of the forest and the tall palms show out black against the yellow sky, and almost before one has time to observe the change the sun has risen straight and fierce, and the whole landscape is bathed in the full light of day. But the morning is for yet another hour cool and fresh, and the scene is indescribably beautiful. The woods, so absolutely silent and still before, break at once into noise and move- ment. Flocks of toucans flutter and scream on the tops of the highest forest trees hopelessly out of shot, the ear is pierced by the strange wild screeches of a little band of macaws which fly past you like the wrapped-up ghosts of the birds on some gaudy old brocade. There is no warbling, no song, only harsh noises, abrupt calls which those who haunt the forest soon learn to translate by two or three familiar words in Portuguese or English. Now and then a set of cries more varied and dissonant than Dec, 20, 1877] NATURE 147 usual tell us that a troop of monkeys are passing across from tree to tree among the higher branches ; and lower sounds to which one's attention is called by the guide indicate to his practised ear the neighbourhood of a sloth, or some other of the few mammals which inhabit the torests of Brazil. And the insects are now all awake, and add their various notes to swell the general din. A butterfly of the gorgeous genus Moipho comes fluttering along the path like a loosely-folded sheet of intensely blue tinsel, flashing brilliant reflections in the sun ; great dark blue shining bees fly past with a loud hum ; tree-bugs of a splendid metallic lustre, and in the most extraordinury harlequin colouring of scarlet and blue and yellow, cluster round a branch so thickly as to weigh it down, and make their presence perceptible yards off by their peculiar and sometimes not unpleasant odour ; but how weak it is to say that that exquisitite little being, whirring and flut- tering in the air over that branch of Bignonia bells, and sucking the nectar from them with its long curved bill, has a head of ruby, and a throat of emerald, and wings of sapphire — as if any triumph of the jeweller's art could ever vie in brilliancy with that sparkling epitome of life and light. " It was broad day when we passed into the dense forest through which the greater part of the way now lay. The path which had been cut through the vegetation was just wide enough for use to ride in Indian file, and with some care to prevent our horses from bruising our legs against the tree- trunks, and we could not leave the path for a single foot on either side, the scrub was so thick, what with fallen tree-trunks, covered with epiphytes of all descriptions, and cycads, and arums, and great thorny spikes of Bro- nielia, and a dense undergrowth, principally of melas- tomads, many of them richly covered with blue and Fig. 2. — Fernando Noronha. purple flovers. Above the undergrowth the tall forest trees ran up straight and branchless for thirty or forty feet, and when they began to branch, a second tier of vegetation spread over our heads, almost shutting out the sky. Great climbing Monsteras and other arals ; and epiphytic bromeUads ; and orchids, some of them distilling from their long trusses of lovely flowers a fragrance which was almost overpowering; and mazes of Tillandsia hang- ing down like tangled hanks of grey twine. Every available space between the trees was occupied by lianas twining together or running up singly, in size varying from, a whipcord to a foot in diameter. These lianas were our chief danger, for they hung down in long loops from the trees and lay upon the ground, and were apt to entangle us and catch the horses' feet as we rode on. As time wore on it got very close and hot, and the forest relapsed into silence, most of the creatures retiring for their noon- day siesta. The false roof of epiphytes and parasites kept off the glare of the sun, and it was only at intervals that a sheaf of vertical beams struck through a rift in the green canopy, and afforded us a passing glimpse of the tops of the forest trees, uniting in a delicate open tracery far above us. " For some hours our brave little horses struggled on, sometimes cantering a little where the path was pretty clear, and more usually picking their way carefully, and sometimes with all their care floundering into the mud- holes, imperfectly bridged o/er with trunks of trees. "As we had made our ascent at first, all this time we had been riding nearly on a level on the plateau between the two river valleys. Suddenly the wood opened, and we rode up to the edge of a long irregular cliff bounding 148 NATURE \_Dec. 20, 1877 the valley of Sto. Amaro. The path ran right up to the edge and seemed to come to an end but for a kind of irregular crack full of loose stones which went zigzagging down to the bottom at an angle of about 70°, and we could see the path down below winding away in the dis- tance towards the main road to Sto. Amaro. We looked over this cliff and told Mr. Wilson firmly that we would tiot go down the side of that wall on horseback. He laughed, and said that the horses would take us down well enough and that he had seen it done, but that it was per- haps a little too much ; so we all dismounted, and put the horses' bridles round the backs of the saddles and led them to the top of the crack and whipped them up as they do performing horses in a circus. They looked over with a little apparent uneasiness, but I suspect they had made that precarious descent before, and they soon began to pick their way cautiously down one after the other, and in a few minutes we saw them waiting for us quietly at the bottom. We then scrambled down as best we might, and it was not till we had reached the bottom, using freely all the natural advantages which Xht Primates have over the Solidunguli under such circumstances, that we fully appreciated the feat which our horses had performed. *' The next part of the road was a trial ; the horses were often up nearly to the girths in stiff clay, but we got through it somehow, and reached Sto. Amaro in time to catch the regular steamer to Bahia," And here is an uncommonly good anecdote about a parrot : — "At Sto. Amaro a line of tramways had lately been laid down also under the auspices of our enterprising fiiend, and we went down to the steamboat wharfs on one of the trucks on a kind of trial trip. The waggon went smoothly and well, but when a new system is started there is always a risk of accidents. As the truck ran quickly down the incline the swarthy young barbarians, attracted by the novelty, crowded round it, and suddenly the agonised cries of a child, followed by low moanings, rang out from under the wheels, and a jerk of the drag pulled the car up and nearly threw us out of our seats. We jumped out and looked nervously under the wheels to see what had happened, but there was no child there. The joung barbarians looked at us vaguely and curiously, but not as if anything tragical had occurred, and we were just getting into the car again, feeling a little bewildered, when a great green parrot in a cage close beside us went through no doubt another of his best performances in the shape of a loud mocking laugh. A wave of relief passed over the party, but we were rather late, and the drivers expressed to the parrot their sense of his conduct, I fear strongly, but in terms which, being in Brazilian patois, 1 did not understand." In another notice we will tell of the Challenoer s doings between Bahia and Cape Town, and from the Falklands home, and we will also more particularly allude to the general results of the scientific work she has so successfully accomplished. {To be continued.) ON THE PRESENCE OF OXYGEN IN THE SUN T HAVE spent the greater part of last winter and the ■^ beginning of this in an investigation of the spectra of oxygen. My experiments will be published, I hope, in another place ; but there are one or two points of more immediate interest, and, I venture to think, of some im- portance, which I trust you will allow me to discuss in ) o jr columns. Prof. Draper has lately announced the important dis- covery that the lines of oxygen are found to be present in the sun. These lines, however, are bright, and not dark, as the Fraunhofer lines. I had found that at a certain temperature, lower than that at which oxjgen shows its well-known lines, it gives another spectrum, and it oc- curred to me, when I heard of Prof Draper's discovery, that if the temperature of the sun, at some point inter- mediate between the photosphere and the reversing layer was the same as that at which the spectrum of oxygen changes, the fact that the known spectrum of oxygen appears bright would be fully explained. The spectrum of lower temperature, which, for reasons to be given, I shall call the compound line spectrum of oxygen, ought in that case to be found reversed in the solar spectrum, like the remainder of the Fraunhofer lines. I have consequently devoted all my time during three weeks to the exact measurement of these four lines, and I do not think that the evidence which I am about to give will be considered to fall far short of an absolute proof that the spectrum is really reversed in the sun. Two difficulties have put themselves into the way of exact measurement. The first is due to the extreme weak- ness of the spectrum. The light itself is not stronger than that of a non-luminous Bunsen burner ; and after that light has passed through four prisms, as in most of my experiments, or through seven, as in some of them, there is not much of a spectrum left to be mea- sured. It is only after having been in the dark for half- an-hour that the eye is able to do the work, and there are a good many days when the eye never obtains sufficient sensitiveness to make any trustworthy measuiements. But whenever my eyes were in sufficiently good con- dition, my measurements agreed so well, that I have no hesitation in saying that they are as accurate as the measurements of the solar lines which will be found by their side. The second and more serious diffi- culty is due to the fact that the lines in question widen to a great extent with increased pressure and in such a way that the brightest part, and still more, the centre of the band, is displaced towards the red. I have not been able to get the lines perfectly sharp, and the measurement of the centre of the band will give, therefore, too high a value of the wave-length. The lollowing table contains the numbers which I have obtained : — Oxygen. Width. Solar ..ines. a 6156 86 ^ 5+35-55 7 5J29-4t 8 4307 62 ±o'3 ±03 ±o'6 A. 615670 5435 '44 53^9 3 4367 58 S. 6156-69 5435 56 532910 The first column contains the wave-length of the com- pound line spectrum of oxygen. The second column contains the number which has to be added or subtracted from the wave-length, in order to get the edge of the lines, as it is their centres which are given in the first column. The third and fourth columns give the wave-lengths of the corresponding solar lines as observed by Angstrom (A ) or myself (S.). The greatest difference is found in the line y, but even this difference only amounts to the twentieth part of the distance between the sodium line?, and it would require a spectroscope of very good dispersive power and definition to separate two lines which would be that distance apart from each other. Nevertheless the amount in question is greater than the possible errors of observation, and 1 believe the difference to be due to the fact mentioned above, that the lines widen unequally. It will be seen from the table that the solar line would fall within the oxygen line, but about one-third of the dis- tance between its most refrangible and least refrangible ed^e. At a higher pressure the brightest part of the bard lies about 5331. None of the other lines widen nearly as much, and S is always perfectly sharp. Angstrom gives it as an iron line, but according to Kirchhotf, the solar line is composed of two lines, and separated by a distance of about o'l. Pec. 20, 1877] NATURE 149 The average distance between the solar lines in the green, which have not yet been identified, is about 4"4, or more than fourteen times the difference between the centre of the oxygen line and the corresponding solar line. The average distance between the non-identified lines near O « is 4'9, or about twenty-nine times the correspond- ing difference. In judging, however, of the value of the evidence, I should like the reader to leave the line S out of account. Although the agreement seems perfect, 1 have not the same confidence in the correctness of the wave-length as I have with the other lines. The line /3 is weaker than the others, and the error of observation may be a little larger than with a and y, which will, I think, be found correct to the decimal place. Let me point out in a few words the importance of the results obtained. The compound line spectrum of oxygen can only exist under a limited range of physical con- ditions. It is broken up at a higher temperature into the elementary line spectrum, and at a lower temperature it tumbles together into a continuous spectrum. During its existence its lines may be subject to variations owing to pressure. The spectrum of oxygen is therefore pre-emi- nently fitted to be at once the pressure gauge and ther- mometer of the sun. We cannot at the present moment give the exact temperature of the points at which the changes take place ; but we can say with certainty why it is that the line spectra of many metalloids are not found reversed in the sun, for the temperature which gives these line spectra is higher than that which gives the compound line spectrum of oxygen, and therefore higher than that of the reversing layer of the sun. Conse- quently we must look for their band spectra and not for their line spectra. The same may be true for the spectra of some of the heavier elements like gold, silver, and platinum, which have not yet been discovered in the sun. The continuous spectrum of the base of the corona is most likely the continuous spectrum of the cooler oxygen. As the science of spectroscopy advances we shall be able to determine the physical conditions which exist on the surface of the sun with as great a degree of certainty and a much smaller degree of discomfort than if we were placed there ourselves. I hope that this communica- tion will prove to be a step in that direction. All my experiments were made in the Cavendish Laboratory. Arthur Schuster St. John's College, Cambridge, November 30 OUR ASTRONOMICAL COLUMN Jupiter's Satellites.— Amongst the recorded pheno- mena connected with the motions of the satellites of Jupiter are several notices of observed occultations of one satellite by another, and of small stars by one or other of the EateUites. The following cases may be mentioned : — On the night of November i, 1693, Christoph Arnold, of Sommerfeld, near Leipsic, observed an occultation of the second satellite by the third at loh. 47m. apparent time. On October 30, 1822, Luthmer, of Hanover, witnessed an occultation of the fourth satellite by the third at 6h. 55m. mean time. Flaugergues, writing to Baron de Zach, from Viviers, on November 18, 1821, says : " I begin with an observa- tion, very useless, no doubt, but extremely rare, for I have not found a similar one in the collections of astronomical observations which I have' examined ; i.e., the occultation of a very small star by the third satellite of Jupiter." He proceeds to mention that on August 14, 1 821, he repaired to his observatory very early to observe an eclipse of this satellite, and having looked at Jupiter with the telescope, he remarked a very small star near the third satellite. The satelhte approached this star, and at ih. 47m. sidereal time, it appeared to touch it, and at ih. 56m. 52s. it was not possible to distinguish the star — it had dis- appeared. The satellite became fainter and disappeared in its turn at ih. 59m. los. sidereal time, on August 13, or i6h. 30m. 8"5s. mean time at Viviers. The sky was perfectly clear, and Flaugergues considered his observa- tions very exact. He adds that he continued to observe for a long time after the immersion of the satellite, hoping to see the star reappear, but he could not again distin- guish it ; the twilight had much increased, and small stars in the neighbourhood of Jupiter were soon effaced. There is a similar observation by Mr. G. W. Hough, at Cincinnati Observatory, communicated in a letter to Dr. Brunnow, when Director of the Observatory at Ann Arbor, Michigan, and published in his "Astronomical Notices" Mr. Hough states that on March 28, i860, he witnessed the end of an expected occultation of a star 9*5 mag., by Jupiter, and the occultation of the same star by the first satellite. When first seen it was distant from the limb of the planet about one diameter of the satellite, or one second of arc, so that the real separation had taken place about six minutes before (or about 8h. 9m. sidereal time), though he was not able to see it. At loh. 27m. sidereal time the star was occulted by the first satellite and re- mained invisible eight minutes. Mr. Hough further says that the star is found in the " Redhill Catalogue," an obvious oversight ; it would appear to be No. 1630 of Zone -f 22° in the DurcJwiiisterung, a. star of 9*3 m. the approximate place of which for 1855 was in R.A. 7h. 8m. 5s., N.P.D. 67°3'-3. DoNATi's Comet of 1858,— This comet which attained so great a celebrity in the autumn of 1858, makes a very close approximation to the orbit of Venus near the descending node, and it may be reasonably inferred that the actual form of its path round the sun may be due to a very near approach of the two bodies at some distant epoch. The discussion of the totality of observations was undertaken some years since by Dr. von Asten, who has published his results in a dissertation entitled " Deter- minatio orbitas grandis cometce anni 1858, e cunctis observationibus." The comet was discovered by Donati on June 2, and was observed until the beginning of March, 1859, at the Cape of Good Hope and at Santiago de Chile ; consequently the observations extended over a very wide arc of the orbit, and there have been very few cases where careful discussion could be expected to lead to more reliable results. The period of revolution deduced by Dr. von Asten is 1,880 years, and there is a high pro- bability that this does not differ materially from the true one, applying to the time of the comet's appearance. Prof. Hill, of Washington, also by a complete inves- tigation, obtained a somewhat longer period, but the general character of the orbit remains the same. Em- ploying Dr. von Asten's elements, it will be found that in heliocentric longitude 343°7, the distance of the comet from the orbit of Venus, is only 0*0047 of the mean dis- tance of the earth from the sun. In 1858 the two bodies came into pretty near proximity, their mutual distance on October 17 being o'o88. It has been mentioned above that the point of closest approach of the orbits of the planet and comet is situated near the descending node ; the opposite node falls in the region of the minor planets. The Observatory of Lyons. — The Bulletin Hebdo- viadaire of the French Scientific Association reports that M. Andre is actively employed in the establishment of this new astronomical institution and is energetically supported by the Government. M. Raphel Bischoffsheim, the munificent donor of the meridian circle, lately mounted at the Observatory of Paris, has also intimated his inten- tion to present the Lyons Observatory with its funda- mental instrument, a meridian- circle of dimensions but slightly inferior to those of the circle, for which the Observatory at Paris is indebted to him. It will also be constructed by Eichens. The Paris meridian-circle is intended to replace the instruments of Gambey, which are now placed in one of the saloons of the institution with other instruments which have seen their day. M. Wolf I50 NATURE {Dec. 20, 1877 remarks that the scientific zeal and liberality of M. Bischoffsheim "inaugurates in France a path long fol- lowed in England by wealthy amateurs of astronomy." The Meteorite of June 14, 1877.— M. Gruey has calculated the orbit of this meteorite with the assistance of the Observatory of the Puy-de-D6me, and accounts obtained through the press of Clermont, where he observed it at 8h. 55m. P.M. local time. Observations made at Bordeaux and at Angouleme were combined with those at Clermont. He obtained for the velocity of the rneteor relatively to the sun 93 kilometres in a second, in the direction - hehocentric longitude 15° 17', latitude - 17° 3', and neglecting the insignificant effect of the earth's at- traction upon a velocity so great, and the unknown effect of atmospheric resistance, he found for the heliocentric motion of the meteor the following elements of a hyper- bolic orbit. Eccentricity, 7079, semi-axis, 0-I37. As- cending node, 83° 49', inclination, 18° 14', perihelion from node, 286° 50', longitude at appearance, 263° 49' ; the meteor approaching its perihelion was thus distant 23° from it. This adds another case to several previous ones in which hyperbolic orbits have been obtained for meteorites by Petit, Galle, Tissot, &c. Prof. Newcomb. — At the meeting of the Royal Society on Thursday last, the distinguished mathematical astronomer, Prof. Simon Newcomb, of Washington, was elected one of its foreign members. There was previously on the list only a single American, viz.. Prof Asa Gray. Prof Newcomb's important contributions to astronomical science will be admitted to have richly entitled him to an acknowledgment at the hands of our leading society. CHEMICAL NOTES Mineral Oil in a Lava of Mount Etna.— In the basaltic zone which reaches from the foot of Mount Etna in a south-south-easterly direction, near the village of Paterno there is a prehistoric doleritic lava containing olivine, which surrounds the clay deposits of a mud volcano and which has been examined by Sig. Orazio Silvestri. Under the microscope the lava shows an augitic principal mass with a quantity of olivine and many white transparent crystals of labradorite. The lava contains numerous round or irregular cavities which are coated with arragonite and which are filled with mineral oil. This oil, of which there is about i per cent, by weight in the whole mass, was taken from one of the cavities at 24° C. At about 17° C. it begins to solidify and is of a yellowish green tint by transmitted light, while by reflected light it is opalescent and light green. Chemical analysis of the liquid proved it to contain : — Liquid hydrocarbons (boiling point 79°*28) ... 17 "97 per cent. Hydrocarbons solidifying under 0° (b. p. 280°- 400°) 31-95 „ „ Paraffine, melting point 52°-57 ... ... 4279 ,, ,, Asphalt (leaving 12 per cent, of ashes) ... 290 „ ,, Sulphur 4-32 „ „ 99 "93 Formation of certain Bodies at Temperatures ABOVE THAT OF THEIR DECOMPOSITION.— MM. Troost and Hautefeuille have lately demonstrated that under certain circumstances it is incorrect to suppose that bodies undergoing decomposition or rather dissociation at a low temperature may not exist as definite compounds at higher temperatures. Their arguments are founded on the decomposition of silicon sesquichloride (SijClg) at 800°, which may be represented as — 2SisCl6 = 3SiCl4 + Si, if, however, the reaction be carried on at a temperature above 1200° the following change takes place — SSiCl^ + Si 2SijCl6. If the tube in which this reaction takes place be cooled suddenly the sesquichloride is found, but if cooled slowly it undergoes gradual decomposition. They also find that although ozone is converted into oxygen at 250°, if a silver tube inclosed in a porcelain tube be kept at about 1300° a deposit of dioxide of silver is produced due to the forma- tion of ozone. They state that the ozone can be recognised by the usual tests if the gas be rapidly drawn off and quickly cooled. They have also examined certain similar phenomena in the production of oxide of silver at 1400°. lODATES OF CORALT AND NiCKEL. — Prof. F. W. Clarke describes these salts, which were prepared by dissolving the carbonates in aqueous iodic acid, and allowing the solution to evaporate spontaneously when salts of the composition Col20(5.6H20 and Nil20Q.6H20 crystallise out. If the solution of the carbonate of cobalt in iodic acid is evaporated rapidly, then the iodate of Rammelsberg, containing i^ molecules of water may be obtained, but not otherwise. The cobalt iodate loses four molecules of water at 100°, but the remaining two molecules cannot be driven off without partial decompo- sition of the salt. The specific gravities of the two salts are almost identical, the cobalt iodate at 21° being 3"6893, the nickel iodate at 22° being 3*6954. No numbers of the solubilities of the two salts are given by Prof. Clarke, but these, when obtained, will be of some interest. Origin and Formation of Boracic Acid. — M. Dieulafait {Comp. Rend, Ixxxv. 605) finds that under certain conditions by spectrum analysis TtrclfTjuTr grammes of boron, and by the colour imparted to a hydrogen flame n)-;r5Tn)(T grammes may be detected. He considers boracic acid to be a normal constituent of sea- water and salt marshes lying above beds of carnallite. M. Dieulafait finds that this acid may be recognised in a drop of sea- water weighing about 0*0378 grammes, and that the minimum quantity found in the Mediterranean is two decigrammes per cubic metre of water. He arrives by geological reasoning at conclusions differing from those of Dumas and others with regard to the origin of this body in the lagoons of Tuscany, and thinks that the source of boracic acid in this district may be found in a relatively modern formation. New Modes of forming Ethylen Oxide.— In the Comptes Rendus, Ixxxv. 624, Mr. H. Greene mentions the results of experiments on the action of certain metallic oxides on the bromide, iodide, and chlcriodide of ethy- lene. Oxide of silver has a rapid action on ethylen iodide at a temperature of 150°, forming ethylen oxide ; its action on ethylen bromide produces the same result but requires a higher temperature. Ethylen bromide and chloriodide both act upon sodium oxide at 180°, the latter of the ethylene compounds being the one found most advantageous by the author in preparing ethylen oxide. He has also studied the action of these substances on the oxides of the diatomic metals barium and lead. These oxides do not give ethylen oxide when heated with bromide or chloriodide of ethylene. These experiments show, on the one hand, the analogy between the silver and sodium oxides confirmed by the isomorphism of their anhydrous sulphates and chlorides, and on the other their difference from the group of diatomic oxides. The Action of certain Antiseptic Vapours on THE Ripening of P'ruits. — MM. Lechartier and Bel- lamy give an account in the Comptes Rendus, Ixxxiv. 1,035, of some experiments they made on the fermenta- tion of apples when inclosed in vapours such as carbolic acid, camphor, and potassium cyanide. From their results it appears that no fermenting action took place in the apples surrounded by vapour of carbolic or hydro- cyanic acids, and a slight act'on only in the one sur- rounded by camphor vapour. The camphor vapour, in fact, diminishes without entirely destroying the vitality of the cells. In this journal, also, there is an account of Dec. 20, 1877] NATURE 151 experiments performed in the same direction by M- Gayon. He mcloses the apples in vapours of chloroform, ether, and carbon disulphide, and his results agree with those of the first observers. The chloroform and ether act in the same manner as the carbolic and hydrocyanic acids ; the carbon disulphide in the same way as camphor, permitting partial fermentation only, A Problem in Chemical Affinity.— In his work on "Gasometric Methods," Prof. Bunsen details an interesting series of experiments on the phenomena accompanying the explosion of hydrogen and carbon monoxide with a volume of oxygen insufficient for its complete combustion. From the results he deduces the conclusion that the ratio between the products of combustion (HgO : CO2) can always be expressed by small whole numbers (i : 2, i : 3, I : 4, &c., and that it alters suddenly from one figure to the next by gradually increasing the amount of hydrogen. Deeming the nine experiments upon which the con- clusion was based as insufficient for the establishment of a general principle, Prof. Horstmann, of Heidelberg, describes in the Verhandlungen des heidelb. naiurf, med. Vereins, an extensive series of observations designed to test the truth of the law. Among his results the follow- ing facts are of interest. In exploding CO with gradually increasing quantities of H, + O, while the ratio between H and CO increased from o'25 : i to 2*33 : I, the ratio between HgO and COg gradually increased from 08 : i to 4"5 : I, with no evidence of a predilection for rational numbers. Experiments on a mixture of CO and H, with gradually increasing amounts of O, led to the same results, showing no such regularity in the division of O between the two combusiiWe gases as Bunsen's law would indicate. When aqueous vapour is present in the mixture less H and more CO unites with O, while the presence of COg reverses the case. By gradually increasing the amount of O in the explosive mixture, it was noticed that the ratio between the resultant HoO and CO^ in- creased until it attained a maximum, when 35 per cent. of the combustible gases were oxidised, and then sank regularly to the ratio denoting complete combustion. The oxygen appears to be divided among the two gases ^curding to the following law : — The ratio between the resultant HgO and CO2 is equal to the ratio between the residual H and CO multiplied by a co- efficient of affinity which is independent of the ratio between the combuitible gases but dependent on the relative quantity of O present. This co-efficient of affinity varied between 4 and 64, showing that always more H relatively than CO is con- sumed, and hence that the affinity of O to H is greater than that to CO, Halogen Derivatives of Amines. — An attempt has frequently been made by chemists to replace the hydrogen in the hydrocarbon group present in amines, by CI, Br, or I. These efforts have hitherto resulted simply in the substitution of the basic H atoms of the amine by halogens — as C2H5.NCI2 — or in complete decomposition. A. Michael {^Berl. Ber,, x., 1644) has devised a method for accomplishing this end, which consists in first replacing these basic H atoms by acid residues, and then exposing to the action of a halogen ethyl-phthalimide, CoH,(CO)2N.C2Hs, yields in this way with Br a tribromo-ethyl-phthallmide. Double Salts with Cyanide of Gold.— C. G. Lindbom publishes in the Univ. Arssh'ijt of Lund an exhaustive account of these compounds, which may be regarded as salts of the two acids, HCy.CyAu and HCy.CyAu.Cy2 + ^2^q-> neither of which, however, can be obtained pure for analysis on account of their tendency to decompose. Most of the auro salts unite directly with a molecule of the halogens ; for example aurocyanide of sodium, NaCysAu, forms bromo-auricyanide of sodium, NaCy2AuBr24-2aq. Aurocyanide of ammonium, AmCygAu, is decomposed at 100°. The Fourth Nitrobenzoic Acid. — Prof. F. Fittica has discovered lately a new nitro-benzoic acid, making the fourth of the isomeric acids, which has been contested, by other chemists, especially as it fails altogether to harmonise with the theories at present accepted in regard to the structure of benzene derivatives. In the October session of the Deutsche chemische Gesellschafr, he strengthens his position by announcing the discovery of a fourth nitro-benzaldehyde, obtained by the action of H2SO4 on benzaldehyde and ethylic nitrate, which on oxidation is changed into th? new nitrobenzoic acjd, C0H4NO3.COOH. Influence of Isomerism on the Formation OF Ethers between Acids and Alcohols.— In the September session of the Russian Chemical Society, Prof. H. N. Menschutkin presented an elabo- rate paper on this subject based on observations of the formation or acetic ethers. The process consisted in inclosing molecular weights of an alcohol and acetic acid in glass tubes, immersing it in a glycerine bath at 154° for a certain time, and then rapidly cooling it, and titrating the unaffected acetic acid with baryta water. The results show that in regard to the rapidity and limits of etherifi- cation, the primary alcohols are sharply divid-'d from the secondary, and the latter from the tertiary ; and the satu- rated alcohols from the non-saturated. A regular decrease in the rapidity coincides with an increase in the mole- cular weight of the ale >hol. As in many other series of experiments, methylic alcohol shows considerable devia- tions from the laws governing its higher homologues. In the case of non-saturated alcohols the rapidity is less than that of the corresponding primary alcohols, but greater than that of the corresponding secondary alcohols. Phosphides of Tin. — Since the introduction of phosphorus bronze, the compounds of phosphorus and the metals are receiving more attention. S. Natanson and G, Vortmenn describe {Berl, Ber., x. 1459), several methods of preparing phosphides of tin, viz., throwing P on molten tin, melting a mixture of vitreous phosphoric acid, charcoal, and tin, and passing phosphorus vapours over molten tin in a hydrogen stream. These processes all yield a crystalline silvt-ry white compound, containing from i^ to 3 per cent, of P, and leaving on treatment with HKO a residue of pure SnP, Chemical Action of Light. — In a late number of the Annales de Chimie et Physique, M. Chastaing ad- vances, in connection with a variety of observations on this topic, the theory that the chemical action of the various coloured rays on inorganic substances is depen- dent on refrangibility, blue and violet acting as reducing agents,' red and yellow causing oxidation. Prof, H, W, Vogel attacks this opinion vigorously in the last session of the German Chemical Society, claiming that the nature of the substance causes the action to be one of reduction or oxidation. The union of H and CI, which takes place so rapidly in violet light, is regarded as purely analogous to oxidation, and he alludes to Timiriazeff's late experi- ments, showing that the reduction of COg by plants, proceeds more rapidly in red light than in green, NOTES At the meeting of the Royal Society, oa Thursday Ia«t, the Times states, tbe following were elected foreign members: — Marcellin Berthelot, of Paris ; Joseph Decaisne, of Paris ; Emil Dubois Reymond, of Berlin ; Adolph Wilhelm Hermann Kolbe, of Leipsic ; Rudolph Leuckart, of Leipsic ; Simon Newcomb, of Washington ; and Pafnutij Tschebytschow, of St. Petersburg. By this election the foreign list of the society is made up to its full complement of fifty members. Mr. Alexander Agassiz, it is understood, proposes to spend the winter in the prosecution of scientific research in the Florida 152 NATURE [Dec. 20, 1877 seas, and will carry a line of dredgings and trawlings from Key West to Yucatan. Bearing in mind the very great success that has been experienced by the use of steel wire in taking soundings, he proposes to try the experiment of a steel rope i jV inches in diameter in the work of dredging and trawling. This, he thinks, will reduce the friction to such an extent as to greatly diminish the time and power necessary in making a cast of the dredge. The Emperor of Russia has conferred the order of St. Anne on Mr. Carl Bock, F.G.S. The Monthly Microscopical Journal expires with the number just issued far the last two months. It was edited from the com- mencement by Dr. Henry Lawson — who, after a long period of failing health, died on October 4 last — and has been in existence for nine years. Many valuable papers are contained in it, by distinguished authors, including the 'Proceedings of the Royal Microscopical Society, which will in future be published inde- pendently. With reference to' the brilliant meteor of December 6, we learn from Capt. Tupman that it will take him some time to determine the most probable path from the immense number of observations, good, bad, and indifferent, sent to him. Mean- time he thinks that Prof. Herschel's preliminary calculation, not yet published, that it began fifty-three miles over Wigan, and burst thirty-three miles over a point half way between Great Orme's Head and Douglas in Man, with radiant 78° -»■ 6° (7 Orionis), agrees better with the observations than any other path. We hope to publish Capt, Tupman's conclusions when bis calculations are completed. The subject of Prof. Tyndall's six Christmas lectures to juveniles is to be Heat, Visible and Invisible. They commence on Thursday week. MM. Feil and Fremy, at last week's meeting of the Paris Academy of Sciences, read a paper describing a new process for the manufacture of rubies and other precious stones. The sen- sation created by these wonderful experiments has been so general that the Association of Jewellers have written to some of the papers stating that it was impossible for human art to com- pete against nature, that mysterious maker having at her disposal an indefinite number of centuries, which is not the case with any human worker, M. Daubree, the Director of the School of Mines, has expressed the wish to open, in the public museum of that magnificent establishment, a gallery for the [exhibition of minerals produced artificially. M. Feil has already produced in his glass foundry, and by the same process as rubies, an im- mense number of stones which can be compared with the most admirable crystalline productions of nature. Some of them are so inexpensive that they may be used for ordinary decorative purposes. An extraordinary but happily unsuccessful attempt was recently made upon the life of Mr. Russell, the Government Astronomer at Sydney, New South Wales. On September 8 a lad of about nineteen years of age left a box at the observatory for Mr. Russell, who, under the impression that it contained instruments of some kind, proceeded to open it. He found the lid a sliding one, similar to those adapted to ordinary instrument cases, and he had not drawn it far when he discovered that the affair partook more of the character of an infernal machine than anything else. The movement of the lid became rather stiff, and upon inspecting it and the box a little more closely he discovered at one end of the latter several grains of powder. The box was then taken into the open air, where it was investigated with special care. The lid was released, and there were found in the box at least i,\ lbs. of blasting-powder. In it were no less than sixteen matches, stuck with their sulphurous points in dangerous proxi- mity to a sheet of sand.paper fastened to the under-side of the lid, the design being evidently to cause an explosion by the friction of the sand-paper against the matches ; and there can be little doubt that this would have been effected had not great care been exercised in handling the affair. Besides the matches and powder, dangerous enough in themselves, a ginger-beer bottle, filled with gunpowder, and evidently intended to act as a shell, was found in the box ; Mr. Russell has expressed his belief that altogether there was a sufficient quantity of explosive material present in the bcx not only to destroy life, but to blow the building down. One of the workmen at the observatory was arrested on suspicion. The first number is announced to appear on January 3 of a new weekly Revue Internationale des Sciences, under the editor- ship of Dr. De Lanessan, Professor of Natural History in the Medical Faculty of Paris. The publisher is Doin, of the Place de I'Odeon, Paris. Among the collaboi-ateurs are several well- known names in France and Germany, England being repre- sented by Mr. Francis Darwin. The expected change has taken place in the French Ministry, M. Faye has resumed his place as one of the Inspectors of Public Instruction, and Member of the Bureau des Longitudes. M. Bardoux, one of the most able members of the republican party, has been appointed Minister of Public Instruction. M. Bardoux is the President of the General Council of Puy de Dome, who constructed, at the expense of the department, the observatory built on the top of the mountain of the same name. M. Bardoux is preparing a bill granting to the rectors of the several French academies (there is one in each of the eighty- two departments) the right to appoint the teachers in the public schools. Up to the present time these nominations were made by the prefects and too often the choice was influenced by political considerations. The enlarged council of the Paris Observatory held last Satur- day a very interesting meeting. M. Faye has not resumed his seat as councillor. Several reclamations were read against the resolutions which had been adopted in the previous sitting. One of them was on behalf of the Bureau des Longitudes, asking to be allowed to have a voice in the presentation of the Director of the Observatory, as well as the Council and the Academy of Sciences. From the foundation of the Bureau des Longitudes up to 1854, when M. Leverrier was appointed director for life by Napoleon HI., the Bureau des Longitudes had the control of the observa- tory. Each year the Bureau appointed one of its members to superintend the observations, and the custom was to reappoint the same member up to his death. Arago thus held his office by yearly tenure for more than a quarter of a century. The discus- sion of meteorological matters was begun, and the meeting adjourned till to-day. No formal proposition will be made to sever the International Bureau from the Observatory, the aim of certain members being confined to the establishment of a Central Board for Meteorology, which will give its advice on the organisation of the .International Bureau, the Montsouris Central Observatory, the Puy de Dome, the Pic du Midi, and any other establishment which may be founded for meteorological purposes. We are happy to state that the rumour widely spread in Paiis of the death of Drouyn de Lhuys is unfounded, the learned gentleman having recovered, against almost all hopes. He will very likely resume his place in the several scientific societies which he had resigned. M. Milne Edwards has been appointed president of the French Scientific Association, which was founded by M. Leverrier thirteen years ago. Under the direction of M. Leverrier the association spent not less than 250,000 francs for scientific purposes, and has accumulated a sum of about 400,000 Dec. 20, 1877] NATURE 153 francs. The association is supported solely by voluntary contri- butions, and meets yearly at Paris. Many improvements are contemplated by the new president. A CHIMPANZEE, about 2\ years old, has been recently placed on view at the Westminster Aquarium by Mr. Farini. It is very gentle indisposition, andlis'undergoing an education in the usages of civilised life at the hands of its keeper, Mr. Zack Coup. For some time it has been in one of the private houses at the Zoological Gardens, and there it caught cold. On its removal to the room at the Aquarium, where a temperature of about 70° is maintained, it improved, but the fog of yesterday (Wednesday) seemed to oppress it very much. It is suffering both in head and lungs, though it still struggles very successfully to be cheerful and enter- taining. It is curious that Pongo's lungs were found all sound, though the few chimpanzees that have been exhibited in Europe have succumbed to lung disease. With the chimpanzee are also a very fine cynocephalus, a "sacred" monkey from India, and a number of monkeys less rare. There are close by a python, a 1 oa, and two anacondas, and in order to insure that they hall not be hidden in rugs when visitors want to see them, they are at intervals exhibited by an Abyssinian girl, who goes through the ceremony of an incantation each time. In his introductory address at the opening meeting of the Royal Society of Edinburgh Sir Alexander Grant stated that the society was an emanation from the University of Edinburgh, from which it sprang on the suggestion of Principal Robertson in the latter part of 1782. Thus, in the same year that the Uni- versity would celebrate its tercentenary the society would be able, perhaps conjointly, to celebrate its looth birthday. In one essential particular it differed from the Royal Society of London. From the first the promotion of literature as well as science was the object of the Royal Society of Edinburgh, But it had been observed that the literary element in their proceedings had been gradually dwindling away. Sir Alexander had inquired as to the number of papers not connected with philosophical science which had been contributed during the last fifteen years, and it appeared to be considerably less than forty, or little more than two per annum. In the last fifteen years, out ot about 370 ordinary Fellows of the Society, only about twenty had come forward to contribute papers other than philosophical or mathematical. The Council of the Society have awarded the Macdougall-Brisbane prize, consisting of a gold medal and 15/. 14J. 7^/., to Mr. Alex. Buchan, for his paper on "The Diurnal Oscillations of the Barometer." Prof. Balfour reported that the membership of the Society at present was 427, con- sisting of 373 ordinary and fifty-four honorary or non-resident Fellows. Adtices from the Howgate Arctic Expedition have been received up to the date of October 2, at which time the vessel had reached Niantitik Harbour, in Cumberland Gulf. The passage of forty-three days from New London had been very stormy, but, as far as reported, without any disaster. Mr. L. Kumlien, the naturalist of the party, had gathered some speci- mens, but did not find the promise of suitable collecting ground in the immediate vicinity very good. He hoped, however, to change his quarters to a better location. We learn from the Isvestia of the Russian Geographical Society, that at the beginning of September M. Prshevalsky had already started for Tibet. He is accompanied by an aid, M. Ecklop, four Cossacks, and two soldiers. Having arrived at the conclusion that it will be impossible to reach Tibet by way of Lake Lob-Nor, he will try the route through Guchen and Hami, and thence to Zaidam and the upper parts of the Blue River. He expects to be at Lassa next year, about May or June, and if he succeeds, he will remain in Tibet for a year. After having penetrated last year for 160 miles up the Amu Daria, the Russian steamer Samarkand has penetrated this year as far as the 'fortified town Chardjui. A complete survey ol the river was made, and considerable botanical and zoological collections were brought back by the officers on board. Russian newspapers announce that the Morning Dawn reached St. Petersburg on December r, having left the mouth of the Yenissei on August 21. This ship, or rather boat,' 56 feet long, 14 feet wide, and drawing only 6 feet water, was built for the transport of wares up the Yenissei from Kureika. It was never intended to go to sea, and "never," Prof. Nordenskjold says, " so wretched a boat dared to enter the waters of the Arctic Ocean." Nevertheless Capt. Swanenberg, with a crew of four men, safely crossed on board this boat the Kara Sea, and reached the Russian capital after a hundred days' cruise. With a com- pass almost useless because of the deviation occasioned by the iron on board, and struggling with ice, he reached, on August 30, the Kara strait, where he experienced a heavy gale. On September 1 1 he was at Vardo. Thence, after a fortnight's stay, the Morning Dawn went in tow of a Norwegian steamer to Christiania, and further, in the same manner, to Goteborg, which was reached on November 3, and to Helsingfors, and finally to St. Petersburg The reception the gallant crew met with in the Norwegian towns was everywhere the most enthusiastic. At the last meeting, December 7, of the Russian Geographical Society, Col. Tillo read a report on the magnetical measurements made by M. Smirnoff in Russia, These measurements, accom- plished with the utmost accuracy, embrace no less than 548 places, the declinations and inclinations having been measured at 287 places, and the former alone at 261. At the same meeting the Society resolved to enter into relations with different govern- ments in reference to the establishment of polar meteorological stations, and to submit an elaborate scheme in connection with that subject to the next International Meteorological Congress. Germany is still waging war against the illegal use of the doctor's title. A " Dr." Harmuth in Berlin who received his diploma from Philadelphia, was lately sentenced to pay 300 marks for using the prefix publicly. M. PoLYAKOFF, who was sent by the St. Petersburg Academy of Sciences for the exploration of the mammoth remains in the Government of Tomsk, has now returned to St, Petersburg after having made a journey in the Western Altai, the Kirghiz Steppe, and in the Seven Rivers' Province, where he visited the lakes Alakul and Balkash. He brings back very rich collec- tions of animals and plants, and the results of his varied obser- vations will appear in the Memoirs of the Academy. The scheme for telegraphing without wires, the New York Tribune states, by means of aerial currents of electricity, has been revived by Prof. Loomis. He has met with success in using kites for this purpose, a copper wire being substituted for the usual kite string. Signals were transmitted thus between kites ten miles apart. His new experiments are made in the mountainous regions of West Virginia, between lofty peaks. Continuous aerial currents are found at these altitudes, which will serve the purposes of the telegraph, except when rarely inter- rupted by violent disturbances of the atmosphere. A scheme is now on foot to test the merits of aerial telegraphy in the Alps. The Journal of Forestry, which started in the month of May last, in the interest of forest conservancy and management gene- rally, maintains the reputation which the early numbers indi- cated. In recent numbers. Prof. Boulger, F.L.S., has con- tributed some papers, which are being continued, on "Cul- tural First Principles," in which he considers (i) "climate," (2) the "nature of the soil," and (3)/* theoretical considerations (as to the treatment of the soil. " In this latter portion of the subject drainage forms of course no inconsiderable part. Sloping plantations, it is shown, will seldom require artificial drainage, '54 NATURE \Pec. 20, 1877 for such a situation on high soils is quite suited for conifers, and if on heavy soils sufficient for^oak and other hard-wooded trees. Mr. Boulger points'out, what ought to be apparent to all, that the growth of rushes, the wood rush {Luziila), the bog asphodel {Nartheciufti), a yellow star-like plant, the tufted hair-grass {Ai7-a c(Espitosa)y or of mosses on the surface, are sure indications of the absolute necessity of drainage. Though these are facts with which a practical forester is well acquainted, it is never- theless necessary to impress them upon the minds of all interested in forest produce. Some useful hints as to the preservation of timber for fencing, or in damp underground situations, are given in the number of the Journal for the current month. R. PiCTET describes some interesting experiments {Arch. Sc, Pkys., lix.) made for the purpose of determining the conditions under which transparent or non-transparent ice is formed. It was ascertained that water frozen in a vessel dipped in a cold glycerine solution formed perfectly transparent ice as long as the temperature ranged between 0° and — i '5°. If the solution was cooled below — 3", the ice was whitish and of a less specific gravity, these properties being intensified with the lowering of the temperature. No difference in the melting-point or amount of warmth required for melting was observable among the various varieties of ice. The opacity of ice results from an irregular arrangement of the ice-crystals, as well as from the presence of small bubbles of air — less than J mm. in diameter — which are mechanically inclosed. They can be removed by slowly conducting through freezing water large bubbles of air which carry with them the small bubbles. At a public meeting held in the Cheltenham Masonic Hall on December 15, Sir F. Abbott in the chair, it was resolved to institute a "Cheltenham Philosophic Society," which should hold its meetings during the winter months. Upwards of fifty gentlemen signified their desire to become members, and a com- mittee was formed to draw up rules to be submitted at a future date to a general meeting for their sanction. Dr. John Rae asks us to state that in his paper on Eskimo skulls read at the Anthropological Institute on May 8 last, and published in the newly-issued number of the Journal of the Institute, he by mistake called the Western Eskimo Brachy- cephalic, whereas they are Mesocephalic. In the letter on the meteor last week, p. 124, "8 (± 2) x Lyrse," should be 8 (± 2) times Lyras. The additions to the Zoological Society's Gardens during the past week include a pair of Musk Deer {Moschus moschiferus), from Central Asia, presented by Sir Richard Pollock ; a pair of Axis Deer {Cervus axis), from India, presented by Dr. Carl Siemens; a Diana Monkey {Cercopithecus diana), from West Africa, presented by Mr. P. Spink ; a Bonnet Monkey {Macacus radiatus), from India, presented by Mr. T. H. Evans ; a Patas Monkey {Cercopithecus rtibtr), from West Africa, a Red-backed Saki {Pithecia chiropotes), a Red-faced Spider Monkey {^Ateles panisais), two Kinkajous {Cercoleptes caudivolvulus), a Coati (Nasua nasica), an Azara's Fox (Canis azares), a Black Vulture (Catharies atratus), from South America, deposited two Schle- gel's Doves {Chalcopelia puella), from West Africa, two Lesser Razor-billed Curassows (Mitua tormentosa), from South America ; two Waxwings {Ampdis garrulus), four Bullfinches {Pyrrhula rubicilla), European, purchased; four Common Waxbills (Estrelda cinerea), two Cinereous Waxbills {Estrelda caru' lescens), six Orange-cheeked Waxbills {Estrelda tnelpoda), two African Silver Bills [Munia canians) seven Yellow-rumped Seed Eaters {Crithagra chrysopyga), from West Africa, received in exchange ; a Chinchilla {Chinchilla lanigera), born in the Gardens. UNIVERSITY AND EDUCATIONAL INTELLIGENCE Cambridge. — The Syndicate, appointed in May, 1875, to consider the requirements of the university in different depart- ments of study, have just issued their fourth report on'the subject. After stating that in their opinion the inter-collegiate system should be further stimulated and supplemented by the institution of university readerships, and that by a more complete organisa- tion the requisite provision for teaching and the encouragement of research might be to a considerable extent made, they never- theless are of opinion that certain subjects of great importance are not now represented in the professoriate, the absence of which from such representation constitutes a serious defect in the Cambridge system, and they recommend that professorships amongst other subjects should be created as soon as the re- sources of the university permit, in comparative philology, mental philosophy and logic, physiology, English language and literature. The Syndicate, with regard to existing professorships, suggest that the Professorship of Mineralogy should be for the future a Professorship of Mineralogy and Mineral Chemistry. There are other subjects of scarcely less importance of which there ought always to be recognised teachers in the University, although the Syndicate are not prepared to say that the teacher ought always to have the status of a professor. Such are analy- tical chemistry, morphological and physiological botany (as dis- tinguished from systematic botany), comparative anatomy (as distinguished from zoology), pathological anatomy. In other subjects, again, it is desirable that the University, without establishing permanent offices, should have the means of appointing professors or other teachers from time to time when there is the opportunity of securing the services of a specially competent person. Such are the theory and^history of education, as also some special departments of natural science. The following is the Natural Science Tripos' list for this year : — Class I. — (2) Ds. Bower, Trinity ; (4) CuUen, Christ's ; (i) Fenton, Christ's ; (l) Greaves, Christ's ; (2 and 3) Hill, Downing ; (i) Ohm, Emmanuel ; (3) Sedgwick, Trinity. Class II. — Ds. Harrison, Christ's ; Holthouse, Trinity ; Houghton, St. John's; Murton, St. John's; North, Sidney; Taylor, E. F. Vinter, Sidney. Class III. — Ds. Allen, St. John's ; Buckmaster, Downing ; Foster, Trinity ; W^allis, St. John's ; Weldon, Caius. The numbers indicate the subjects for knowledge of which the candidates are placed in the first class as follows : — i. Physics, chemistry, and mineralogy. 2 . Botany. 3. Zoology and com- parative anatomy, human anatomy, and physiology. 4. Geology. Edinburgh. — The second meeting of the session of the Edin- burgh University Chemical Society, was held on the 12th instant, John Gibson, Ph.D., F.R.S.E., vice-president, in the chair. J. S. Thomson communicated a paper on solutions of litmus, in which he explained the preservation of the colour of such solu- tions on exposure to the air by the action of the air preventing fermentation. He also read a paper on the Determination of Melting Points. Technical University. — It may be remembered that a Committee of the City Companies has been for some time at work elaborating a scheme for founding a technical university in London. The last step taken by the Committee was to procure reports and suggestions from six specially nominated referees, viz.. Prof. Huxley, Col. Donnelly (of the Science and Art De- partment), Capt. Douglas Galton, Mr. H. T. Wood (Assistant- Secretary of the Society of Arts), and Mr. Bartley (of the Science and Art Department). After having decided on these names, the Committee adjourned to allow time for the preparation of the reports. On Thursday last week they met again, and the reports were laid before them. After some discussion the further consideration of the subject was adjourned till January 17. Taunton College School. — The Science Scholarship at Keble College, Oxford, is awarded to Mr. R. G. Durrant, of the Taunton College School. This is the fourth brilliant success that the school has gained in the last five months, and it is pro- bably the last. The able science master, Mr. Shenstone, leaves at Christmas to take a Science Mastership at the revived Exeter Grammar School. He will not be replaced at Taunton, and the science teaching, which, after years of toil against obstacles, is just beginning to bear fruit, will become a thing of the past. Dec, 20, 1877] NATURE 155 Austria. — The Austrian Government has for a number of years been accustomed to bestow liberal grants to the more promising students in the universities, under the condition that the recipients shall make use of them to undertake a course of study in the German universities. The results of this plan seem to be satisfactory, for we notice that this winter an unusually large number of students in all branches have been sent to the various universities in Germany, A Berlin Polytechnic, — Berlin, with all her numerous educational establishments, has lacked hitherto a polytechnic such as is to be found in most of the German industrial centres at the present day. This want will soon be repaired, a com- mission having completed the plans for an extensive institution which will embrace nearly every branch of technical education. The plans for the necessary buildings have already been prepared, and as there is but little doubt that the Prussian Chamber of Deputies will grant the 9,300,000 marks required, the work of erection will commence next spring, l On account of the exten- sive character of the proposed edifices, five years will be required for completion. SOCIETIES AND ACADEMIES London Mathematical Society, December 13. — C. W. Merrifield, F.R.S., vice-president, in the chair.— The Rev. W. Ellis was elected a member. — Mr. S. Roberts read a paper on normals, which contained theorems depending on the invariants and co- variants of the quartic equation representing a pencil of four normals to a conic, and drew attention to the remarkable cubic locus of the points of possible concurrence of these normals at the vertices of a given inscribed triangle. — Dr. Hirst and Mr. J. J. Walker spoke on the subject. Prof. Cayley, F.R.S., read a paper on * ' the geometrical representation of imaginary quantities and the real (nt, n) correspondence of two planes." Linnean Society, November 15. — Dr. Gwynjeflreys, F.R.S., vice-president, in the chair. — Mr. J. Jenner Weir exhibited a case of Alpine butterflies, interesting for their similarity to,, though not specifically identical with, those obtained by the naturalists of the Polar Expedition. — Three papers on the Arctic fauna followed. I. Report on the Insecta including Arachnida, collected by Capt. Feilden and Mr. Hart during the recent Arctic expedition, by R. McLachlan. It seems there were obtained of Hymenop- tera 5, Coleoptera i, Lepidoptera 13, Diptera 15, Hemiptera I, Mallophaga 7, Collembola 3, Araneida 6, and of Acarida 6 species, namely, a total of 57 species. Bearing in mind these are from localities between 78° and 83° N. lat., that among them are thirty-five specimens of gaily- coloured butterflies and two species of humble-bees, and it becomes evident the insect-fauna of this so-called " land of desolation " is, after all, not so meagre as anticipated. The paucity of beetles and abundance of butter- flies are each striking features. From variations in certain well- known species obtained, Mr. McLachlan suspects they represent a local fauna, and he regards the latter as having affinity to the Lapland fauna, inclining to think both are but lingering rem- nants of a once former and extensive circumpolar fauna. — IL Preliminary notice on the surface fauna of the Arctic Seas as observed in the recent Arctic expedition, by Dr. Edw. L. Moss (late surgeon, H.M.S. Alert). The author observes that the seas north of the Greenland settlements are subject to such varying conditions at different seasons of the year that their surface-fauna cannot be supposed to be very constant. Never- theless, judging from what fell under his observation during the voyage, he divides the watery area into three zoological regions : (a) A district in the latitude of Melville Bay, temporarily mono- polised by infusoria, Peridinea : (b) a north- water region inhabited by Pteropods, Tunicates, and Hydrozoa ; and {c) a sub-glacial region comparatively lifeless, so far as sea-surface implies. — III. On the annelids of the British North Polar Expedition (1875-76), by Dr. W. C. Mcintosh. This collection, dredged between 70° and 82° N. , was not so rich in numbers or species as that pro- cured by the storeship Valorous in Davis Straits, but some eight species were got which were not among the latter's collection. None are new, but notwithstanding they help to render clear some points in the geographical distribution of the marine worms, so far as the circumpolar area is concerned, — Dr. H. Trimen exhibited specimens of the Olibanum, or Frankincense tree (Boswellia carterii, Birdw. ), gathered by Mr. J. Collins from the trees planted at Aden. Dr. Trimen, in making some remarks on the variability of the foliage of the species of Boswellia, ex- pressed the opinion that j9. Bhau-Dajiania, Birdw. , was not speci- fically separable from B. Carterii. B. Frereana, which yields the fragrant resin called " Luban Metyi," and which Hanbury con- sidered to be the African "Elemi," is much chewed by Orientals, but rarely imported into England. It is found in the Somali land, where Hildebrandt recently collected it. —The following gentlemen were elected Fellows of the Society : Mr. W. S. Lawson, Mr. W. Joshua, and the Rev. M. A. Mactherd. Geological Society, December 5. — Prof. P. Martin Duncan, F.R.S., president, in the chair, — Dr, Isaac Bayley Balfour, David Burns, Samuel Cooke, Henry Drummond, Sandford Fleming, Rev. John Hodgson, William Etheldred Jennings, Henry Merry- weather, Robert Robinson, Martin Stewart, George Eastlake Thoms, Robert F. Tomes, and Irwine J. Whitty, were elected Fel- lows of the Society. — A portrait of Mr. J. Evans, D.C.L., F,R,S., V.P.G.S., was presented by the President. — Tlie following com- munications were read : — On the building-up of the White Sinter Terraces of Roto-Mahkna, New -Zealand, by the Rev. Richard Abbay, M.A., F.G.S. — Additional notes on the Dimetian and Pebidian Rocks of Pembrokeshire, by Henry Hicks, F.G.S. The additional facts communicated by the author show that at a distance of about ten miles to the east of the Dimetian axis of St. David's there is another ridge of these rocks, which also runs nearly parallel with it. This is also flanked by Pebidian and Cambrian rocks, and made up of rocks like those in the St. David's axis. The Dimetian formation, so far as it is at present known, consists chiefly of the following rocks : — i. Quartz por- phyries, containing frequently perfect quartz crystals (double pyramids), subangular masses of quartz, and crystals of felspar in a felspathic matrix. 2. Fine-grained greyish quartz-rocks, very compact, and interstratified with the above. 3. Ashy- looking shales of a dull green colour, sometimes highly indur- ated, but usually showing lines of lamination. Microscopically these show basaltic characters, and are probably greatly altered interbedded basaltic lavas. 4. Compact granitic-looking rocks. 5. Quartziferous breccias. 6. A series of compact quartzites and crystalline schists, interstratified by green and purple altered basaltic lavas, with a slaty and schistose foliation, and by some dolomitic bands. Of the Pebidian formation new areas were added, and the portions described in the author's previous paper were further extended, and details as to the chief mineralogical characters added. At the base of the series resting unconform- ably on the Dimetian is seen an agglomerate composed of large angular masses of a spherulitic felstone, pieces of quartz and quartzites, indurated shales, crystalline schists, &c., cemented together by a sea-green matrix of felstone. These are followed by conglomerates of the same materials, which are again sue ceeded by indurated shales, often highly porcellanitic in charac- ter, with a conchoidal fracture. These are followed by a thick series of silvery white and purplish shales and green slates, alter- nating with fine and rough ashes, often conglomeritic, hornstone breccias, felstone lavas, &c. The series, as exhibited at St. David's, has a thickness of over 8,000 feet ; and as it is every- where, so far as yet seen, overlapped unconformably by the Cambrians, it may probably be of much greater thickness. It evidently consists very largely of volcanic materials, at first derived from subaerial, but afterwards from submarine, volca- noes. These materials, however, were also undoubtedly con- siderably aided by sediments of a detrital origin. The whole series shows that the sediments have undergone considerable changes, but yet not sufficient to obliterate the original charac- ters, and the lines of lamination and bedding are usually very distinct. That they were altered nearly into their present state before the Cambrian sediments were deposited upon them, is clear from the fact that the pebbles of the Cambrian conglome- rates which rest immediately on any portion of the series are almost invariably made up of masses of the rocks below, cemented by gritty materials on an unaltered matrix, and from which the pebbles may be easily removed. The great conglomerates at the base of the Cambrians, everywhere in Wales, indicate that there were beach- and shallow-water conditions over those areas at the time, and that the sea was then encroaching on an uneven land, becoming gradually depressed to receive the subsequent Cambrian sediment. — On some pre-Cambrian (Dimetian and Pebidian) rocks in Caernarvonshire, by Henry Hicks, F.G.S. In this paper the author gave an account of the special examina- tion of the great ribs of so-called intrusive felspathic and quartz porphyries which are found associated with the Cambrian rocks in Caernarvonshire, made by him in company with Prof. Hughes, 156 NATURE [Dec. 20, 1877 Mr. Hudleston, and Mr. Homfray last summer. — On the pre- Cambrian rocks of Bangor, by Prof. T. McKenny Hughes, F.G. S. The author described a series of slates, agglomerates, and porphyritic rocks which, near Bangor, are seen to pass under the Cambrian and seem to rest conformably upon the quartz felsites and granitoid rocks of Caernarvon. He considered that in the ma'n the Bangor beds were the equivalents of the Pebidian of Dr. Hicks, while the Caernarvon beds nearly represented his Dimetian. But he thought there was as yet no proof of an un- conformity between these formations. — An appendix by Prof. Bonney, on the microscopical examination of the rocks referred to, accompanied this paper. Royal Microscopical Society, December 5. — Mr. H. C, Sorby, president, in the chair. — The president announced that in consequence of the death of Dr. Lawson it had become neces- sary to reconsider the subject of publication, and the Council had, after careful attention to the matter, decided in future to publish their own proceedings. — A paper by Herr Zeiss on Abbe's apertometer was read by Mr. Ingpen, who exhibited the apparatus to the meeting and further explained its construction and method of application by means of black-board diagrams. Mr. Ingpen also described the method of measuring angular "apertures last adopted by Mr. F. H. Wenham. — A paper by Mr. F. A. Bed well on Cephalosyphon was read by Mr. Slack, who afterwards explained the structure of this rotifer, and pointed out the special features to which attention was drawn by the author of the paper. — Another paper by the same author on a new method of examining Actinia mesembryanthemum, was read by Mr. Chas. Stewart ; it was illustrated by drawings, some of which were enlarged upon the black-board. Institution of Civil Engineers, December 11. — Mr. George Robert Stephenson, president, in the chair. — A description of Cofferdams used at Dublin, Birkenhead, and Hull, by Mr. WiUiam James Doherty, Assoc. Inst C.E., was read. GOTTINGEN Royal Academy of Sciences, August 24. — The division of a language into several different languages, by M. Benfery. — On the earthquake of Iquique on May 9, 1877, and the tidal move- ments thereby produced in the ocean, by M. Geinitz. November 7. — Report on the Physical Institute (department of experimental physics), from 1871 to 1877, by M. Riecke. November 14. — D instead of N, by M. Benfery. — Contribu- tions to physiography of rock-forming minerals, by M. Lang. November 21. — Antiquities in the south-west of Switzerland, and in Turin, by M. Wieseler. — On the secondary intestine of the echinoidese, by M. Ludwig. — Obituary notices of M. Hartmann and M. Marx. Paris Academy of Sciences, December 10. — M. Peligot in the chair : — The following papers were read : — On some appli- cations of elliptical functions (continued), by M. Hermite. — On invariants, by Prof. Sylvester. — On the arrangements which, in the system of a navigation sluice with single oscillation, conduce to the maximum of production and the minimum of expense of construction, by M. De Caligny. — On the development of eggs of the phylloxera of the oak, and the phylloxera of the vine, by M. Boiteau. — M. Volpicelli sent a note tending to prove, by means of potential, that induced electricity of the first species has no ten- sion.— Application of Leyden jars of large surface for distributing, at various points, the effect of the current from a single source of electricity, with strengthening of the effect, by M, Jablochkoff. Connecting one surface of such an apparatus (called in this case an exciter) with one of the conductors of a machine which gives alternate currents, an alternating current is got by the other sur- face of the exciter and the second conductor (or the earth), more powerful than the current given directly by the machine. If a series of exciters with surfaces of nearly 500 square metres be thus connected with a machine which gives a spark equivalent to that of six or eight Bunsen elements, a voltaic arc of 15 to 20 mm. is obtained, and carbons of 5 mm. diameter are red- dened to an extent of 6 to 10 mm. from their extremity. Such effects are utilised in electric lighting. — On the law of absorption of radiations through bodies, and its employment in quantitative spectrum analysis (continued), by M. Gov). He shows how sur- faces of chromatic absorption may be obtained by means of the analysing photometer, measuring the various simple radiations which take part in a complex radiation. — On some properties of chloride of calcium, by M. Ditte. He dea's with the calorific phenomena accompanying the reaction of water with this chloride • If the latter be anhydrous, a heating is observed, and fresh addi- tions of water cause successive heatings ; but if the chloride be hydrated, its mixture with water produces at first a considerable cooling followed by heating if some more of the solvent be added. — Application of palladium wire to determination of the hydro- carbons mixed in a small proportion with air, by M. Coquillion. It is necessary to operate with a cherry-red, near white-red. The results agreed with theory. — On the development of the functions of M. Weierstrass according to the increasing powers of the variable, by M. Andre. — On the lesions of the nervous system in diphtheritic paralysis, by M. Dejerine. There is an atrophy of the anterior roots, which follows destruction of the cells of the anterior horns of the spinal cord, by a process similar to that of myelitis. — Orography, by M. Schrader. The author presented a geographical map of Mont Perdu, made with his orograph, which consists of a circular paper-covered plate with central vertical axis carrying a sleeve which can turn round freely. On the top of the sleeve is a telescope, the movements of whose frame in the vertical direction are communicated to a pencil, and transformed by gearing into to and fro movements. If the tele- scope describes a circle round the horizon, the style describes a corresponding circle on the plate ; if the telescope goes up or down, the trace produced is further from or nearer to the central axis. A spirit level being fixed to the telescope, the circle made when it is even, 'gives a means of estimating the heights and depressions. — On the folding of the lacustrian strata of Auvergne in Central Limagne, and its consequences, by M. Olivier. — Influence of soil and forests on climate ; temperatures of air layers over woods; consequences as regards vegetation j effects of currents arising from differences of temperature under wood and beyond wood, by M. Fautrat. The frigorific action of the forest is very manifest in the hot season. Under pines in September the temperature is lowered i '60°. Pure sand raises the temperature of a place. Leafy woods, during vegetation, produce a slight lowering of temperature in the atmosphere above. Above pines, in the daytime, there is always a rise of temperature, from the solar heat being retained by the vapours enveloping the tree-tops. From the differences of temperature within and without woods, a current arises in the wood from below upwards, and round the woods course lateral currents from the wood to the plain. — On the disinfecting properties of cellulosic substances carbonised by concentrated sulphuric acid, by M. Garcin. CONTENTS PAjE The "Inflexible" 137 Hydrophobia, II 139 Dikn's "Celestial Atlas" 141 Our Book Shblf : — Burbidge's " HotticuUure" , 142 Meyer's " Mittheilungen aus dem k. zoologischen Museum zu Dresden "...., 142 Letters to the Editor :— The Radiometer and its Lessons — Prof. G. Carey Foster, F.R.S. ; Dr Arthur Schuster 142 The Proposed Channel Islands' Zoological Station, Aquarium, aud Piscicultural Institute — W. A. Lloyd 143 The ■' Challenger " Estimates of the Volume of the Gulf Stream — T. Mkllaru Reade 144 The Fossil Peronospora as a Primordial^ Plant. — Worthington G. Smith 144 The "Challenger" IN the Atlantic (W/M ///Kj^r«/«(7«i) . . . 145 On the Presence of Oxygen im the Sun. By Dr. Arthur Schuster 148 Our Astronomical Column : — Jupiter's Satellites 349 Donati's Comet of 1858 149 The Observatory of Lyons 149 The Meteorite of June 14, 1877 150 Prof. Newcomb 150 Chemical Notes ; — Mineral Oil in a Lava of Mount Etna 150 Formation of Certain Bodies at Temperatures above that of their Decomposition 150 lodates of Cobalt and Nickel 150 Origin and Formition of Boracic Acid 150 New Modes of Forming Ethylen 0\ygen 150 The Action of certain Antiseptic Vapours on the Ripening of Fruits ISO A Problem in Chemical Affinity 151 Halogen Derivatives of Amines 151 Double Salts with Cyanide of Gold 151 The Fourth Nitrobenzoic Acid 151 Influence of Isomerism on the Formation of Ethers between Acids and Alcohols 151 Phosphides of Tin 151 Chemical Action of Light 151 Notes 151 University AND Educational Intblligenck 154 Societies amo Academies 155 NA TURE 157 THURSDAY, DECEMBER 27, 1877 THE METROPOLITAN SEWAGE THE question of the effect of the main outfall sewers of the metropolis on the reaches of the Thames below London has occupied the attention of engineers rot only since the completion of the works, but through- cut the long series of years when those works were under consideration. Some persons qualified to make accurate observations and draw correct deductions from them, asserted that large masses of deposit were directly due to these outfalls, and were daily increasing in magnitude, while others, demanding equal confidence in their state- ments, asserted that no such deposits existed— in fact, that the sewage outfalls tended to improve the bed of the river by increased scour ; thus the bulk of engineers for a long time held diverse views or suspended judgment on the subject, while the general public, not knowing whom to believe, trusted it would turn out all right in the end. Inasmuch as the Metropolitan Board of Works is bound, under the Thames Navigation Act of 1870, to keep the Thames free from banks and other obstructions to the navigation due to the flow of sewage from their outfalls, and to carry on all dredgin g operations required for that purpose, at their own expense, the vision of the possible cost of these works to the London ratepayer is unlikely to be pleasing ; still less could any interference with the highway to the most important port in the world be tolerated by the Board who were looked to for its preser- vation. In 1869, the metropolitan main outfalls having been opened in 1863-64, the Home Secretary appointed Mr. Rawlinson to hold an inquiry on the reported silting up of the Thames, which was then causing great alarm ; such, however, was the contradictory nature of the evi- dence, that the result was almost nugatory, and the ques- tion still remained in abeyance. In the course of the last summer the Thames Conservators requested Capt. Calver, R.N., F.R.S., to direct his attention to the subject, and report to them thereon. Before pointing out the conclu- sions arrived at by Capt. Calver,^ it will be as well to direct attention to the part of the river under considera- tion. The northern outfall is situated immediately above Barking Creek, which forms the embouchure of the river Reding, and is about two miles below Woolwich ; the southern outfall is about 2\ miles lower, or 4^ miles below Woolwich. In the face of the fact that this special inquiry was held and many competent witnesses examined with the sole object of determining whether or no the sewage outfalls have caused a silting up of the river in their neighbourhood, or i the formation of shoals and mudbanks, and that so many j observations and statements have since been made with the same view, it seems perfectly monstrous that the quesiion should still remain unsettled. In the report now before us we have the last contribution on the subject, or perhaps, with more fairness it might he said the last but one, as since its publication Sir Joseph Bazalgette has addressed to the daily press a letter containing a direct « " Report upon the Discharge of Metropolitan Sewage into the River Thames at Barking Creek and Crossncis." By Capt. E. R. Calver, R.N., F.R.S. Vol. XVII.—- No. 426 denial of many of the conclusions thete arrived at. When professional experts differ so entirely not only in their conclusions, but also in the facts upon which these con- clusions are based, we see no other course open but to appeal to the cooler and more unbiased judgments of pure science. In comparing the analyses of Thames mud from various parts of the river, given in Capt. Calver's report, em- bodying a series taken in 1867, and another in 1868, by the late Dr. Letheby, with those given by Dr. W. A. Miller, and Dr. W. Odling in 1869, so close an agreement is manifest that a safe conclusion can be drawn from them. The analyses are as follows :— Average Percentage Composition. Organic matter 1500 14-19 1867 Dr. Letheby. Mineral „ 8500 85-81 1868 „ 10000 100 'OO On these analyses Dr. Letheby remarks that the above percentage proportions did not differ materially from the quantities of organic and sewage matters which he found suspended in water at London Bridge, and in the mud at London Bridge, Chelsea, and Westminster, when the sewage was discharged at low water. The next table gives nearly identical results from the analysis of the mud at the outfalls in 1867, and those of the suspended matter in the Thames water at Greenwich, Woolwich, and London Bridge in 1862, by the same chemist. Now, Dr. W. A. Miller so far agrees with these results that in his evidence, given at the inquiry before referred to in 1869, he states the percentage of organic matter in the mud taken from Barking Creek to be i6-2, from the Thames between Chiswick and Westminster, 158, and further, that of these two quantities 3-1 and 3-05 respectively con- sists of nitrogen, and finally, in answer to the question : " But there is nothing special and differing in the mud at Barking from the ordinary mud of the River Thames ? " he says : No, the composition is as nearly the same as may be. With these observations Dr. Odling's evidence closely agrees. Here, then, we have an agreement which nobody appears to dispute, and which leads inevitably to the con- clusion that the great bulk of noxious putrescible matter left uncovered at low water throughout the whole of the tidal portion of the Thames owes its deleterious character mainly, if not entirely, to the presence of sewage matters. Having carefully pointed out and established this identity of composition, Capt. Calver proceeds : " It is, however, equally necessary to prove that there is enough of this material in the sewage discharged from the out- falls to account for the large accumulations of it which have found a resting-place in the Thames channel." Here we are met by estimites differing in the wildest manner, and varying from 35 to 100 grains per gallon, and again to neariy double that amount, but fortunately we are here even given material for a trustworthy estimate. In the table of analysis given by Prof. WiUiamson of samples taken from the northern outfall in September of this year we find io8-oi and 15 1*45 grains per gallon as the actual amount of suspended solid matter at different times, the samples being collected in fine weather. Now abundant evidence has been given at various times, show- ing that after heavy rain the sewage contains an amount 158 NATURE {Dec. 27, 1877 of solid impurity equal to, if not greater than, that in the fine-weather flow ; thus there can be no doubt that the lower of these two figures is not in excess of the average. Capt. Calver takes the amount at 100 grains per gallon, and multiplying by the daily discharge quoted as 120 million gallons, he obtains a result of 279,225 tons per annum. This probably does not exceed one-half the true amount, as the water supply of the metropolis alone reaches the amount assumed for the daily discharge, and the rainfall over the drainage area gives nearly an equal amount, which, for the reason just stated, must be taken into account. We thus appear to have at command upwards of half a million tons of suspended matter dis- charged into the Thames in each year, which is amply sufficient to account for the deposits observed. Thus we read in the report that " Mr. Leach (the engineer of the Thames Conservancy Board) reported in December (187 1) that a deposition of 7 feet 9 inches of mud had formed between the upper end of the southern embankment and the White Hart Draw Dock, Lambeth ; that another bank 100 feet wide and 6 feet thick occupied the river- frontage of St. Thomas's Hospital, &c. By July of last year a material portion of these masses had been cleared away by excessive rainfalls." Are we to be left to the mercy of such an unpleasant remedy as the floods of last autumn to abate a nuisance of such magnitude, threaten- ing, as it does, the existence of such an institution as St. Thomas's Hospital, and showing how soon we may return to the unsanitary state of affairs that existed twenty-five years ago ? We have purposely avoided dealing with an equally important part of Capt. Calver's report, in which he points out the danger of the silting up of the navigable channel of the Thames below London, as he has not shown that the sectional area, though varying from year to year, has at any point permanently diminished, still the destructive elements have been shown to exist, and the forces which now hold them in equi- librium may at any time be thrown out of balance and the evil creep on imperceptibly if once the eyes of the public are closed to its existence. Without going into the question of the value of the sewage estimated by the highest authorities at 1,000,000/. per annum, thus not only wasted but employed as a powerful obnoxious agent, enough has been shown from the report before us to, we hope, show the suicidal folly of discharging sewage whole- sale and unpurified into tidal rivers. Yet even now a scheme is under consideration for the collection of the sewage from a large area in the Thames Valley and for its discharge into the tidal waters of the Thames. We believe that a careful perusal of Capt. Calver's Report will dispel from the minds of the Thames Valley Joint Board all hopes of a satisfactory though expensive solu- tion of their difficult problem being arrived at in this manner. As a remedy for the state of things he has shown to exist Capt. Calver recommends that in pur- suance of the powers they possess the Conservancy Board call upon the Metropolitan Board to dredge away the obstructions they have caused ; this may be indis- pensable at present and may be an unavoidable and con- stantly recurring expense until some profitable scheme is devised for utilising the metropolitan sewage ; in the meanwhile the example of the inhabitants of Abingdon, as shown by the letter of their medical officer of health in the Sanitary Record of November 30, shows the inutility of other towns in the valley of the Thames striving to follow the example of London, and further increasing its difficulties. We learn from Dr. Woodforde's letter that the whole of the sewage of the town of Abingdon is purified by filtration through natural soil being frequently absorbed by one acre of land, and that the amount of organic and inorganic impurity contained in the effluent water after passing through the land is far less, in some cases less than one half that contained in the well water used for drinking purposes in the town. As this unprecedented result has been obtained on land of a character which exists in abundance throughout the Valley of the Thames we think that the towns situated therein have not far to look for the solution of their difficulties. BOTANY IN GERMANY f ahrbiicher/ur wissenschaftliche Botanik. Herausgegeben von Dr. A. Pringsheim. Elfter Band. Erstes und Zweites Heft. (Leipzig : W. Engelmann, 1877.) THE second decade of volumes of the Jahrbiicher is now begun, and up to the present shows no sign of any falling off" from the high standard of excellence attained by the former parts It is somewhat remarkable that such a work can be carried on successfully. Profusely illustrated (having about 500 plates in the ten vols.), and containing papers of great merit, it is at once evidence of the marvellous botanical activity of the Germans, and the energy of their publishers. A glance at the list of papers in the ten volumes shows that the Jahrbiicher contain papers that have become classical, and have been contributed by men who have risen to the highest eminence in botanical science. Comparatively few of the papers are contributed by Russians or Italians, hence this one work may be looked,,on as almost wholly the result of German research. The papers contributed are chiefly morphological and physiological, although occasionally one having immediate bearings on taxonomy is introduced. There can be little doubt that the German university system tends greatly to foster original research, not only in botany, but in all other departments. The botanical institutes, with laboratory, garden, and her- barium attached,? the way in which the students are induced not only to learn but to work under the superin- tendence of the professor, the whole system of private teachers and mode of promotion of the professors fosters research, and gives a thoroughness and heartiness to the work. In certain departments of botany, Britain is second to none with her Hooker, Bentham, and Darwin, but when we consider the enormous " microscope " power of Britain, we cannot help thinking that^ much of it goes to waste. There must be hundreds of microscopists residing near our coasts, yet what do we know of the reproduction of our algae ? A glance at the " Botanischer Jahresbericht " shows how few British botanists there are, and also that each contributes comparatively few papers per year. But quality is better than quantity — work slowly and well. The time is no doubt coming when we may look for increased botanical activity, perhaps the union of botanical studies to medicine has had something to do with the comparative depression, and if botany be- Dec. 27, 1877] NATURE 159 comes a preliminary instead of a purely professional study by becoming more diffused, a greater taste for the subject may arise. Prof. Pringsheim contributes th'e first paper, one part dealing with the interesting subject of the budding of the fruit of mosses, the second on the alternation of genera- tion in the Thallophytes, a subject suggested by the first part. If the seta of the ripe fruit of the moss be cut into pieces, and the pieces cultivated on wet sand, protonema threads will grow from the cut portions, and produce the usual buds, exactly Uke protonema threads developed from the spores or stem and leaves of mosses. The anatomical connection of the protonema with the tissue of the seta can be observed in good longitudinal sections. Not all the cells can give rise to protonema, but only those of the middle zone, situated between the peripheral cortical cells and the central bundle. These cells contain abundance of reserve matter, such matter being found in many parts of the moss-fruit. The product of protonema by the seta of the moss is to be compared to the budding of the prothallium of ferns described by Farlow. Prings- heim figures in the two plates illustrating the paper, the protonema developing from the seta of Hypniim serpens^ H. cupressiforme^ and Bryum caespitosiim, and he shows the stem and seta to be identical structures. The second part of the paper, on the alternation of generation in Thallophytes, is difficult to follow without illustrations, as it takes for granted that the reader is acquainted with all the recent researches on the lower plants. Pringsheim distinguishes between sexual alterna- tion of generations and vegetative alternation of genera- tions (sprosswechsel), the fructification and vegetative propagation. AH the generations of Thallophytes (as well as of the Cormophytes) begin with one free cell (the spore). The generations in the Thallophytes represent free individual plants, while in the Cormophytes the generations remain in organic connection and in their individual sequence appear only as two portions of one series of developments. From this it follows that the " fruits " of Thallophytes never have the value of a " generation," and also that where the development is due to sexual influence, they are only sexually influenced organs of the female plant. Such parts are the fruits of Floridece, also apparently the Perithecia and Apothecia of Ascomycetes, which do not behave differently from the calyptra of the moss or the thickened tissue (gewebe- polster) of the prothallum, in which the embryo of the vascular cryptogams is developed. Pringsheim believes that in the trichogyne and ascogon the influence of fertilisation is spread from cell to cell until it reaches the spores, just as in mosses and ferns the reverse process occurs, and the influence spreads from the fertilised germinal cell to the archegonium. Carpospores and asco- spores are therefore to be regarded not as sexually- produced spores of a sexually-produced generation, but as truly sexually-produced spores, developing in the sexually- influenced organ of the mother plant. The second paper, illustrated by two plates of diagrams, and occupying nearly half the part, is by F. G. Stebler, " Researches on Leaf-growth." The numerous obser- vations made on A Ilium Cepa, Secale cereale, T^'iticmn vul- var e, Cucurbita melanospertna, are detailed at full length, and the following summary of the result of the paper is given at the conclusion. The leaf begins to grow very slowly, then growth becomes more rapid until a maximum of rapidity is reached ; then growth becomes slower and slower until at last it ceases. The leaf thus behaves like other growing parts of plants. The growth of the linear monocotyledonous leaf is basipetal. The apex zone of the leaf ceases earliest to grow, then succeeding zones in basipetal order, until lastly the growth of the basal zone terminates the growth of the entire leaf. Most produc- tive of increase in length is the growth in the basal zone, but at different times the maximum activity is in different zones, the absolutely greatest zone of growth proceeding in succession from the upper part of the leaf to the lower. The maximum period of growth of the whole leaf is the sum of the maximum periods of all the zones. The linear monocotyledonous leaves examined in reference to alternations of growth by day and night showed a daily periodicity of growth, the growth dimi- nishing as the intensity of the light diminishes. The maximum of growth corresponds to the greatest intensity of light ; the minimum is observed to occur shortly before sunrise. The cause of the daily periodicity of growth is assimilation ; as assimilation increases the growth in- creases ; as it diminishes the growth diminishes. The same daily periods of growth were observed in etiolated linear monocotyledonous leaves in the dark, the external conditions being constant. The periodicity has thus been transmitted. In the dicotyledonous leaves observed the daily periods were modified, so that after the maximum of growth was reached in the forenoon a retardation took place, and a gradual diminution of the growth till the following morn- ing before sunrise. At daybreak the growth rapidly increases again to reach a maximum in the forenoon. If the intensity of the light is small the maximum is later of occurring than if the light be very intense. The maximum of the day periods of growth of the dicotyledonous leaf is due to the assimilation. The retard- ation during the day occurring after the maximum of growth (but not the maximum of light) has been reached, is due to the action of the light. The third paper occupying the remainder of the part is by Dr. Celakovsky, and is entitled, " Teratological Con- tributions to the Morphological Import of the Stamens." It is illustrated by three plates. Considerable uncertainly still exists as to the morphological value of the different parts of the stamen, but more especially of the anther. The difficulty does not exist in regard to the pollen- bearing caulomes, but there are still difficulties in those cases where the stamens are modified leaves. Whether the question can be settled by the study of the develop- ment alone is a matter of doubt, even after the valuable researches of Warming and Engler on the subject ; and it appears likely that the most important results may be expected from the careful study of the numerous abnor- malities of stamens so constantly met with. The scien - tific study of the teratological developments of stamens must therefore be looked upon as of the highest import- ance, and Celakovsky — already well known by his tera- tological researches, here describes and figures the changes (phyllody) of the stamens of Rosa chinetisis, Dictamnus albus, and in the double flower of Camellia japonica. i6o NATURE [Dec, 27, 1877 There are two important questions to be answered. I. Are the pollen-sacs mere enlargements of the leaf- substance of the staminal leaf, or are they special deve- lopments somewhat like "emergence's"? 2. Do these sacs belong to the under side, upper side, or both sides of the leaf ; or are there differences of position in different plants ? Cassini and Roeper held that the pollen-sacs were cavities in the leaf-parenchyma, two forming on each side of the leaf, so that the margin of the leaf corresponded to the suture between the sacs. Mohl considered this view only to hold for certain cases, as the Euphorbiacese, and found, what Bischoff had already pointed out, that in all examples examined, as in poppy, rose, and nigella, the four pollen sacs were placed on the ttpper side of the leaf, and that the margin of the leaf ran along the two posterior or lower loculaments. Mohl did not consider the sacs as "emergences," and differing morphologically from the true leaf, as he says that the connective represents the central portion of the modified leaf, while the loculaments are the thick swollen lateral halves, which become con- tracted in length and breadth. Mohl considered that in the plants with extrorse anthers both the loculaments of each anther lobe were developed on the under side of the leaf. Alexander Braun pointed out in 1851 that the anthers were produced by doubling of the lamina (Ueber- spreitung). This view was confirmed by Wydler in 1852, who compared the anther to the abnormal double lamina in the leaf of Bignonia. Sachs considers the anthers to be appendages of the leaf. He compares each loculament in the anther of Cycads and Cupressineas to Sporangia ; the four pollen- sacs in the Metasperms being " emergences " from the upper side of the leaf, those of the Archisperms from the lower side. Braun still further examined the subject and confirmed his original views, namely, that the pollen-sacs do not belong to a simple leaf, but to one with a double lamina, the doubling due to the formation of an *' emer- gence " (in Karl Schimper's, not in Warming and Sachs' sense). The two upper anther sacs belong to the " emergence," the two posterior to the original lamina of the leaf. Celakovsky in the paper now before us departs from the views published by him in Flora for 1874, and fully confirms the views of Braun and Wydler. The second part of vol. xi. contains five papers by Pfitzer, Koch, Reinke, and Reinsch. Dr. Pfitzer's paper is on the rapidity of the current of water in the plants. It contains an elaborate series of researches, the first on the movement of leaves due to the absorption of water by the stem and root ; the second by means of solution of lithium. Dr. McNab's experiments are extended and confirmed, but the astonishing rapidity of 22 metres per hour was observed in Helianthus annus, the greatest rapidity observed by Dr. McNab being 40 inches per hour in Primus Lauro-cerasus. Pfitzer also uses a solu- tion of soluble indigo carmine 4 parts to 1,000, and finds that it is superior to solution of lithium, as it can be detected at once instead of using the spectroscope. The second paper is by Dr. Ludwig Koch, on the development of the seeds of Orobanchaceas. The deve- lopment of the anatropal ovule, with one integument is described, and the development of the embryo. This agrees with the description given by Hanstein, of the embryo of Capsella. The endosperm is formed of divi- sions of embryo-sac, which contains antipodal vesicles before fertilisation. The third and fourth papers are by Prof. Reinke, both on the development and reproduction ofalgae, of the genera Phyllitis,Scytosiphon,Asperococcus, and Bangia, the observations having been made at the Zoological Station at Naples, during the winters of 1875 and 1876. The last paper is by Reinsch : " Observations on new Saprolegnies, on parasites in cells of Desmedics, and on the * Spinous Spheres ' in Achyla." A number of new species and genera are described and fully illustrated. W. R. M'Nab MOVING DIAGRAMS OF MACHINERY Patent Working Drawings. By H. and T. C. Batchelor (London : Macmillan and Co.) A LL who are engaged in the teaching of kinematics -^^ and of applied mechanics must ofcen have ic brought forcibly before them the difficulty that exists in making even comparatively simple mechanical motions intelli- gible to students by means of ordinary drawings and diagrams, while the more complex motions and com- binations can hardly be treated of at all profitably with- out the aid of working models, which are very expensive, and take up a great deal of space. Again, inventors and the proprietors of patented mechanical inventions, are often at a loss to explain to unscientific or uninitiated persons the advantages of their systems, and costly working models have to be resorted to in order to avoid the mystification which ordinary mechanical drawings often produce in the minds of those not accustomed to them, or who are not versed in the principles of mechanics. To supply this recognised need of teachers and others, Messrs. H. and T. C, Batchelor have designed and worked out a most ingenious system which combines the mechanical movements of a model with the flatness and clearness of a diagram. The name "Working Drawings" applied to these diagrams is somewhat misleading, especially to engineers and others accustomed to this term as having a distinct and special meaning, namely, drawings made for and used by the workmen employed upon the construction of machinery to worK from. Working drawings are essentially drawings for the workshop, and that is the universal acceptation of the word. The meaning attached to it by Messrs. Batchelor is, however, very different; it is drawings which will work moving diagrams. This sense is, perhaps, more critically correct, but as another meaning is the generally accepted one, we cannot but think that it would have been wise if a name had been given to these diagrams more descriptive of what they are. Tney are, in fact, moving diagrams or sectional working models of machines, the fixed parts being lithographed as a back- ground upon a firm cardboard mount, and the movino^ parts being also lithographed on card, but cut out and jointed together by most ingenious mechanical contri- vances ; the whole being no thicker than a sheet of stout cardboard. The perfection of the centres upon which the various parts revolve or are pivoted together must be seen to be adequately appreciated, for while these centres allow perfect ease of motion to all the parts, they are absolutely Dec, 27, 1877] NATURE 161 steady and without the slightest shake. It is this system of centrin:.^ that constitutes the patent by which Messrs. Batchelor's drawings are protected. The pivots are made entirely of card and paper cut in a most ingenious manner, by which both freedom and steadiness are insured. Nor are the centres the only parts of these drawings interesting for their ingenuity; the contrivance for holding down the sliding parts is equally good. It consists of a band of thin paper passing over the sliding part, and printed exactly like the part it covers, so that it is invisible except on close examination. The first of these drawings which is before us is a diagram in illustration of the action of the "trunk engine," the characteristic feature of which consists in making the piston-rod hollow and of sufficient internal diameter to allow the connecting-rod to be attached at one end direct to the piston, and to oscillate within the trunk, the other end embracing the crank-pin. By this means the crank shaft can be brought nearer to the cylinder, considerable space thereby being saved, and the alternative system by which direct connection between the piston and crank is effected, viz., the oscillating cylinder, is avoided, with its more complicated valve gear and expensive construction. The double trunk system represented in the drawing was the invention of the late Mr. John Matthew, who for many years was a partner in the eminent firm of Messrs. John Penn and Sons, and it is the system upon which, almost without exception, the large screw engines of Messrs. Penn are constructed, with which so many of the ships in her Majesty's navy are fitted. There is nothing to be desired in the execution of the diagram before us, of which the name of Messrs. Maclure and Macdonald is a sufficient guarantee. It is litho- graphed in white upon a blue ground, and all the parts come out with singular distinctness. We could have vsfished that, in the choice of an example for illustration, a more modern design of engine had been selected. The eccentric rod, with its lattice bracing, is that em- ployed in the old beam engines, and a trunk engine made to the drawing before us could hardly work, for the crank pin is evidently inserted into one of the spokes of the fly-wheel, and unless projecting to an impossible extent, the trunk could not clear the wheel ; this could very easily have been remedied by shovving the '' throw " of a crank behind the connecting-rod, which would have aided rather than detracted from the clearness of the diagram. While thus criticising the particular design of engine selected for representation, we can only express admira- tion of this most ingenious system of illustrating mecha- nical motions and the action of machines. For educational purposes it will be of the highest value, and there are many of the examples in Reuleaux's masterly work upon the " Kinematics of Machinery," ^ so ably translated by Prof. Kennedy, to which it might with great advantage be applied. We feel sure that Messrs. Batchelor's drawings will be a great boon to inventors for explaining their inventions to others ; and as supplementary to scientific evidence in dispu-ied patent cases and other litigation, they will be found of value. C. W. C. ' "Thoretisthe Ki emit'k." LETTERS TO THE EDITOR \The Editor does not hold himself responsible for opinions expressed by his correspottdents. Neither can he undertake to return, or to correspo7id with the writers of, rejected manuscripts. No notice is taken of anonymous communications. The Editor urgently requests correspotidents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the app arance. evf.n of com- municatiens containing interesting and novel facts.\ Oxygen in the Sun From the time of the discovery by Prof. Draper of the presence of oxygen in the sua down to the present moment I have devote 1 m;)st of iny leisure time to the consideration of the question as to why the oxygen lines should appear brii^ht while the mefallic lines should appear dark in the solar spectrum. I was led into this inquiry under the firm belief that the new fact made known by Dr. Draper might learl to a modification of existing views of the sun's atmosphere, and it was consequently with th